Merge remote-tracking branch 'remotes/philmd-gitlab/tags/avr-port-20200711' into staging

8bit AVR port from Michael Rolnik. Michael started to work on the AVR port few years ago [*] and kept improving the code over various series. List of people who help him (in chronological order): - Richard Henderson - Sarah Harris and Edward Robbins - Philippe Mathieu-Daudé and Aleksandar Markovic - Pavel Dovgalyuk - Thomas Huth [*] The oldest contribution I could find on the list is from 2016: https://lists.nongnu.org/archive/html/qemu-devel/2016-06/msg02985.html Tests included: $ avocado --show=app run -t arch:avr tests/acceptance/ Fetching asset from tests/acceptance/machine_avr6.py:AVR6Machine.test_freertos (1/1) tests/acceptance/machine_avr6.py:AVR6Machine.test_freertos: PASS (2.13 s) RESULTS : PASS 1 | ERROR 0 | FAIL 0 | SKIP 0 | WARN 0 | INTERRUPT 0 | CANCEL 0 JOB TIME : 2.35 s $ make check-qtest-avr TEST check-qtest-avr: tests/qtest/boot-serial-test TEST check-qtest-avr: tests/qtest/cdrom-test TEST check-qtest-avr: tests/qtest/device-introspect-test TEST check-qtest-avr: tests/qtest/machine-none-test TEST check-qtest-avr: tests/qtest/qmp-test TEST check-qtest-avr: tests/qtest/qmp-cmd-test TEST check-qtest-avr: tests/qtest/qom-test TEST check-qtest-avr: tests/qtest/test-hmp TEST check-qtest-avr: tests/qtest/qos-test CI results: . https://cirrus-ci.com/build/5697049146425344 . https://gitlab.com/philmd/qemu/-/pipelines/165328058 . https://travis-ci.org/github/philmd/qemu/builds/705817933 . https://app.shippable.com/github/philmd/qemu/runs/822/summary/console # gpg: Signature made Sat 11 Jul 2020 10:03:11 BST # gpg: using RSA key FAABE75E12917221DCFD6BB2E3E32C2CDEADC0DE # gpg: Good signature from "Philippe Mathieu-Daudé (F4BUG) <f4bug@amsat.org>" [full] # Primary key fingerprint: FAAB E75E 1291 7221 DCFD 6BB2 E3E3 2C2C DEAD C0DE * remotes/philmd-gitlab/tags/avr-port-20200711: (32 commits) target/avr/disas: Fix store instructions display order target/avr/cpu: Fix $PC displayed address target/avr/cpu: Drop tlb_flush() in avr_cpu_reset() target/avr: Add section into QEMU documentation tests/acceptance: Test the Arduino MEGA2560 board tests/boot-serial: Test some Arduino boards (AVR based) hw/avr: Add limited support for some Arduino boards hw/avr: Add some ATmega microcontrollers hw/avr: Add support for loading ELF/raw binaries hw/misc: avr: Add limited support for power reduction device hw/timer: avr: Add limited support for 16-bit timer peripheral hw/char: avr: Add limited support for USART peripheral tests/machine-none: Add AVR support target/avr: Register AVR support with the rest of QEMU target/avr: Add support for disassembling via option '-d in_asm' target/avr: Initialize TCG register variables target/avr: Add instruction translation - CPU main translation function target/avr: Add instruction translation - MCU Control Instructions target/avr: Add instruction translation - Bit and Bit-test Instructions target/avr: Add instruction translation - Data Transfer Instructions ... Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
author: Peter Maydell <peter.maydell@linaro.org> 2020-07-11 19:27:59 +0100
committer: Peter Maydell <peter.maydell@linaro.org> 2020-07-11 19:27:59 +0100
commit: d34498309cff7560ac90c422c56e3137e6a64b19 (patch)
tree: 0a5207cc1a1a637b5abb3db997b503c1ce9f5375
parent: 2033cc6efa98b831d7839e367aa7d5aa74d0750f (diff)
parent: 19b293472f1514b5424ef4d9b092e02bd9b106c2 (diff)
49 files changed, 7172 insertions, 1 deletions
diff --git a/MAINTAINERS b/MAINTAINERS
index 361ae5c662..fe8139f367 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -167,6 +167,14 @@ S: Maintained
 F: hw/arm/smmu*
 F: include/hw/arm/smmu*
 
+AVR TCG CPUs
+M: Michael Rolnik <mrolnik@gmail.com>
+R: Sarah Harris <S.E.Harris@kent.ac.uk>
+S: Maintained
+F: gdb-xml/avr-cpu.xml
+F: target/avr/
+F: tests/acceptance/machine_avr6.py
+
 CRIS TCG CPUs
 M: Edgar E. Iglesias <edgar.iglesias@gmail.com>
 S: Maintained
@@ -982,6 +990,28 @@ F: include/hw/*/nrf51*.h
 F: include/hw/*/microbit*.h
 F: tests/qtest/microbit-test.c
 
+AVR Machines
+-------------
+
+AVR MCUs
+M: Michael Rolnik <mrolnik@gmail.com>
+R: Sarah Harris <S.E.Harris@kent.ac.uk>
+S: Maintained
+F: default-configs/avr-softmmu.mak
+F: hw/avr/
+F: include/hw/char/avr_usart.h
+F: hw/char/avr_usart.c
+F: include/hw/timer/avr_timer16.h
+F: hw/timer/avr_timer16.c
+F: include/hw/misc/avr_power.h
+F: hw/misc/avr_power.c
+
+Arduino
+M: Philippe Mathieu-Daudé <f4bug@amsat.org>
+R: Sarah Harris <S.E.Harris@kent.ac.uk>
+S: Maintained
+F: hw/avr/arduino.c
+
 CRIS Machines
 -------------
 Axis Dev88
diff --git a/configure b/configure
index ee6c3c6792..31e2ddbf28 100755
--- a/configure
+++ b/configure
@@ -8143,6 +8143,10 @@ case "$target_name" in
     mttcg="yes"
     gdb_xml_files="aarch64-core.xml aarch64-fpu.xml arm-core.xml arm-vfp.xml arm-vfp3.xml arm-neon.xml arm-m-profile.xml"
   ;;
+  avr)
+    gdb_xml_files="avr-cpu.xml"
+    target_compiler=$cross_cc_avr
+  ;;
   cris)
   ;;
   hppa)
@@ -8387,6 +8391,9 @@ for i in $ARCH $TARGET_BASE_ARCH ; do
       disas_config "ARM_A64"
     fi
   ;;
+  avr)
+    disas_config "AVR"
+  ;;
   cris)
     disas_config "CRIS"
   ;;
diff --git a/default-configs/avr-softmmu.mak b/default-configs/avr-softmmu.mak
new file mode 100644
index 0000000000..80218add98
--- /dev/null
+++ b/default-configs/avr-softmmu.mak
@@ -0,0 +1,5 @@
+# Default configuration for avr-softmmu
+
+# Boards:
+#
+CONFIG_ARDUINO=y
diff --git a/docs/system/target-avr.rst b/docs/system/target-avr.rst
new file mode 100644
index 0000000000..dc99afc895
--- /dev/null
+++ b/docs/system/target-avr.rst
@@ -0,0 +1,37 @@
+.. _AVR-System-emulator:
+
+AVR System emulator
+-------------------
+
+Use the executable ``qemu-system-avr`` to emulate a AVR 8 bit based machine.
+These can have one of the following cores: avr1, avr2, avr25, avr3, avr31,
+avr35, avr4, avr5, avr51, avr6, avrtiny, xmega2, xmega3, xmega4, xmega5,
+xmega6 and xmega7.
+
+As for now it supports few Arduino boards for educational and testing purposes.
+These boards use a ATmega controller, which model is limited to USART & 16-bit
+timer devices, enought to run FreeRTOS based applications (like
+https://github.com/seharris/qemu-avr-tests/blob/master/free-rtos/Demo/AVR_ATMega2560_GCC/demo.elf
+).
+
+Following are examples of possible usages, assuming demo.elf is compiled for
+AVR cpu
+
+ - Continuous non interrupted execution:
+   ``qemu-system-avr -machine mega2560 -bios demo.elf``
+
+ - Continuous non interrupted execution with serial output into telnet window:
+   ``qemu-system-avr -machine mega2560 -bios demo.elf -serial
+   tcp::5678,server,nowait -nographic``
+   and then in another shell
+   ``telnet localhost 5678``
+
+ - Debugging wit GDB debugger:
+   ``qemu-system-avr -machine mega2560 -bios demo.elf -s -S``
+   and then in another shell
+   ``avr-gdb demo.elf``
+   and then within GDB shell
+   ``target remote :1234``
+
+ - Print out executed instructions:
+   ``qemu-system-avr -machine mega2560 -bios demo.elf -d in_asm``
diff --git a/docs/system/targets.rst b/docs/system/targets.rst
index 99435a3eba..560783644d 100644
--- a/docs/system/targets.rst
+++ b/docs/system/targets.rst
@@ -19,3 +19,4 @@ Contents:
    target-xtensa
    target-s390x
    target-rx
+   target-avr
diff --git a/gdb-xml/avr-cpu.xml b/gdb-xml/avr-cpu.xml
new file mode 100644
index 0000000000..c4747f5b40
--- /dev/null
+++ b/gdb-xml/avr-cpu.xml
@@ -0,0 +1,49 @@
+<?xml version="1.0"?>
+<!-- Copyright (C) 2018-2019 Free Software Foundation, Inc.
+
+     Copying and distribution of this file, with or without modification,
+     are permitted in any medium without royalty provided the copyright
+     notice and this notice are preserved.  -->
+
+<!-- Register numbers are hard-coded in order to maintain backward
+     compatibility with older versions of tools that didn't use xml
+     register descriptions.  -->
+
+<!DOCTYPE feature SYSTEM "gdb-target.dtd">
+<feature name="org.gnu.gdb.riscv.cpu">
+  <reg name="r0" bitsize="8" type="int" regnum="0"/>
+  <reg name="r1" bitsize="8" type="int"/>
+  <reg name="r2" bitsize="8" type="int"/>
+  <reg name="r3" bitsize="8" type="int"/>
+  <reg name="r4" bitsize="8" type="int"/>
+  <reg name="r5" bitsize="8" type="int"/>
+  <reg name="r6" bitsize="8" type="int"/>
+  <reg name="r7" bitsize="8" type="int"/>
+  <reg name="r8" bitsize="8" type="int"/>
+  <reg name="r9" bitsize="8" type="int"/>
+  <reg name="r10" bitsize="8" type="int"/>
+  <reg name="r11" bitsize="8" type="int"/>
+  <reg name="r12" bitsize="8" type="int"/>
+  <reg name="r13" bitsize="8" type="int"/>
+  <reg name="r14" bitsize="8" type="int"/>
+  <reg name="r15" bitsize="8" type="int"/>
+  <reg name="r16" bitsize="8" type="int"/>
+  <reg name="r17" bitsize="8" type="int"/>
+  <reg name="r18" bitsize="8" type="int"/>
+  <reg name="r19" bitsize="8" type="int"/>
+  <reg name="r20" bitsize="8" type="int"/>
+  <reg name="r21" bitsize="8" type="int"/>
+  <reg name="r22" bitsize="8" type="int"/>
+  <reg name="r23" bitsize="8" type="int"/>
+  <reg name="r24" bitsize="8" type="int"/>
+  <reg name="r25" bitsize="8" type="int"/>
+  <reg name="r26" bitsize="8" type="int"/>
+  <reg name="r27" bitsize="8" type="int"/>
+  <reg name="r28" bitsize="8" type="int"/>
+  <reg name="r29" bitsize="8" type="int"/>
+  <reg name="r30" bitsize="8" type="int"/>
+  <reg name="r31" bitsize="8" type="int"/>
+  <reg name="sreg" bitsize="8" type="int"/>
+  <reg name="sp" bitsize="8" type="int"/>
+  <reg name="pc" bitsize="8" type="int"/>
+</feature>
diff --git a/hw/Kconfig b/hw/Kconfig
index 62f9ebdc22..4de1797ffd 100644
--- a/hw/Kconfig
+++ b/hw/Kconfig
@@ -43,6 +43,7 @@ source watchdog/Kconfig
 # arch Kconfig
 source arm/Kconfig
 source alpha/Kconfig
+source avr/Kconfig
 source cris/Kconfig
 source hppa/Kconfig
 source i386/Kconfig
diff --git a/hw/avr/Kconfig b/hw/avr/Kconfig
new file mode 100644
index 0000000000..d31298c3cc
--- /dev/null
+++ b/hw/avr/Kconfig
@@ -0,0 +1,9 @@
+config AVR_ATMEGA_MCU
+    bool
+    select AVR_TIMER16
+    select AVR_USART
+    select AVR_POWER
+
+config ARDUINO
+    select AVR_ATMEGA_MCU
+    select UNIMP
diff --git a/hw/avr/Makefile.objs b/hw/avr/Makefile.objs
new file mode 100644
index 0000000000..4dca064bfc
--- /dev/null
+++ b/hw/avr/Makefile.objs
@@ -0,0 +1,3 @@
+obj-y += boot.o
+obj-$(CONFIG_AVR_ATMEGA_MCU) += atmega.o
+obj-$(CONFIG_ARDUINO) += arduino.o
diff --git a/hw/avr/arduino.c b/hw/avr/arduino.c
new file mode 100644
index 0000000000..65093ab6fd
--- /dev/null
+++ b/hw/avr/arduino.c
@@ -0,0 +1,149 @@
+/*
+ * QEMU Arduino boards
+ *
+ * Copyright (c) 2019-2020 Philippe Mathieu-Daudé
+ *
+ * This work is licensed under the terms of the GNU GPLv2 or later.
+ * See the COPYING file in the top-level directory.
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+/* TODO: Implement the use of EXTRAM */
+
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "hw/boards.h"
+#include "atmega.h"
+#include "boot.h"
+
+typedef struct ArduinoMachineState {
+    /*< private >*/
+    MachineState parent_obj;
+    /*< public >*/
+    AtmegaMcuState mcu;
+} ArduinoMachineState;
+
+typedef struct ArduinoMachineClass {
+    /*< private >*/
+    MachineClass parent_class;
+    /*< public >*/
+    const char *mcu_type;
+    uint64_t xtal_hz;
+} ArduinoMachineClass;
+
+#define TYPE_ARDUINO_MACHINE \
+        MACHINE_TYPE_NAME("arduino")
+#define ARDUINO_MACHINE(obj) \
+        OBJECT_CHECK(ArduinoMachineState, (obj), TYPE_ARDUINO_MACHINE)
+#define ARDUINO_MACHINE_CLASS(klass) \
+        OBJECT_CLASS_CHECK(ArduinoMachineClass, (klass), TYPE_ARDUINO_MACHINE)
+#define ARDUINO_MACHINE_GET_CLASS(obj) \
+        OBJECT_GET_CLASS(ArduinoMachineClass, (obj), TYPE_ARDUINO_MACHINE)
+
+static void arduino_machine_init(MachineState *machine)
+{
+    ArduinoMachineClass *amc = ARDUINO_MACHINE_GET_CLASS(machine);
+    ArduinoMachineState *ams = ARDUINO_MACHINE(machine);
+
+    object_initialize_child(OBJECT(machine), "mcu", &ams->mcu, amc->mcu_type);
+    object_property_set_uint(OBJECT(&ams->mcu), "xtal-frequency-hz",
+                             amc->xtal_hz, &error_abort);
+    sysbus_realize(SYS_BUS_DEVICE(&ams->mcu), &error_abort);
+
+    if (machine->firmware) {
+        if (!avr_load_firmware(&ams->mcu.cpu, machine,
+                               &ams->mcu.flash, machine->firmware)) {
+            exit(1);
+        }
+    }
+}
+
+static void arduino_machine_class_init(ObjectClass *oc, void *data)
+{
+    MachineClass *mc = MACHINE_CLASS(oc);
+
+    mc->init = arduino_machine_init;
+    mc->default_cpus = 1;
+    mc->min_cpus = mc->default_cpus;
+    mc->max_cpus = mc->default_cpus;
+    mc->no_floppy = 1;
+    mc->no_cdrom = 1;
+    mc->no_parallel = 1;
+}
+
+static void arduino_duemilanove_class_init(ObjectClass *oc, void *data)
+{
+    MachineClass *mc = MACHINE_CLASS(oc);
+    ArduinoMachineClass *amc = ARDUINO_MACHINE_CLASS(oc);
+
+    /* https://www.arduino.cc/en/Main/ArduinoBoardDuemilanove */
+    mc->desc        = "Arduino Duemilanove (ATmega168)",
+    mc->alias       = "2009";
+    amc->mcu_type   = TYPE_ATMEGA168_MCU;
+    amc->xtal_hz    = 16 * 1000 * 1000;
+};
+
+static void arduino_uno_class_init(ObjectClass *oc, void *data)
+{
+    MachineClass *mc = MACHINE_CLASS(oc);
+    ArduinoMachineClass *amc = ARDUINO_MACHINE_CLASS(oc);
+
+    /* https://store.arduino.cc/arduino-uno-rev3 */
+    mc->desc        = "Arduino UNO (ATmega328P)";
+    mc->alias       = "uno";
+    amc->mcu_type   = TYPE_ATMEGA328_MCU;
+    amc->xtal_hz    = 16 * 1000 * 1000;
+};
+
+static void arduino_mega_class_init(ObjectClass *oc, void *data)
+{
+    MachineClass *mc = MACHINE_CLASS(oc);
+    ArduinoMachineClass *amc = ARDUINO_MACHINE_CLASS(oc);
+
+    /* https://www.arduino.cc/en/Main/ArduinoBoardMega */
+    mc->desc        = "Arduino Mega (ATmega1280)";
+    mc->alias       = "mega";
+    amc->mcu_type   = TYPE_ATMEGA1280_MCU;
+    amc->xtal_hz    = 16 * 1000 * 1000;
+};
+
+static void arduino_mega2560_class_init(ObjectClass *oc, void *data)
+{
+    MachineClass *mc = MACHINE_CLASS(oc);
+    ArduinoMachineClass *amc = ARDUINO_MACHINE_CLASS(oc);
+
+    /* https://store.arduino.cc/arduino-mega-2560-rev3 */
+    mc->desc        = "Arduino Mega 2560 (ATmega2560)";
+    mc->alias       = "mega2560";
+    amc->mcu_type   = TYPE_ATMEGA2560_MCU;
+    amc->xtal_hz    = 16 * 1000 * 1000; /* CSTCE16M0V53-R0 */
+};
+
+static const TypeInfo arduino_machine_types[] = {
+    {
+        .name          = MACHINE_TYPE_NAME("arduino-duemilanove"),
+        .parent        = TYPE_ARDUINO_MACHINE,
+        .class_init    = arduino_duemilanove_class_init,
+    }, {
+        .name          = MACHINE_TYPE_NAME("arduino-uno"),
+        .parent        = TYPE_ARDUINO_MACHINE,
+        .class_init    = arduino_uno_class_init,
+    }, {
+        .name          = MACHINE_TYPE_NAME("arduino-mega"),
+        .parent        = TYPE_ARDUINO_MACHINE,
+        .class_init    = arduino_mega_class_init,
+    }, {
+        .name          = MACHINE_TYPE_NAME("arduino-mega-2560-v3"),
+        .parent        = TYPE_ARDUINO_MACHINE,
+        .class_init    = arduino_mega2560_class_init,
+    }, {
+        .name           = TYPE_ARDUINO_MACHINE,
+        .parent         = TYPE_MACHINE,
+        .instance_size  = sizeof(ArduinoMachineState),
+        .class_size     = sizeof(ArduinoMachineClass),
+        .class_init     = arduino_machine_class_init,
+        .abstract       = true,
+    }
+};
+
+DEFINE_TYPES(arduino_machine_types)
diff --git a/hw/avr/atmega.c b/hw/avr/atmega.c
new file mode 100644
index 0000000000..7131224431
--- /dev/null
+++ b/hw/avr/atmega.c
@@ -0,0 +1,458 @@
+/*
+ * QEMU ATmega MCU
+ *
+ * Copyright (c) 2019-2020 Philippe Mathieu-Daudé
+ *
+ * This work is licensed under the terms of the GNU GPLv2 or later.
+ * See the COPYING file in the top-level directory.
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/module.h"
+#include "qemu/units.h"
+#include "qapi/error.h"
+#include "exec/memory.h"
+#include "exec/address-spaces.h"
+#include "sysemu/sysemu.h"
+#include "hw/qdev-properties.h"
+#include "hw/sysbus.h"
+#include "hw/boards.h" /* FIXME memory_region_allocate_system_memory for sram */
+#include "hw/misc/unimp.h"
+#include "atmega.h"
+
+enum AtmegaPeripheral {
+    POWER0, POWER1,
+    GPIOA, GPIOB, GPIOC, GPIOD, GPIOE, GPIOF,
+    GPIOG, GPIOH, GPIOI, GPIOJ, GPIOK, GPIOL,
+    USART0, USART1, USART2, USART3,
+    TIMER0, TIMER1, TIMER2, TIMER3, TIMER4, TIMER5,
+    PERIFMAX
+};
+
+#define GPIO(n)     (n + GPIOA)
+#define USART(n)    (n + USART0)
+#define TIMER(n)    (n + TIMER0)
+#define POWER(n)    (n + POWER0)
+
+typedef struct {
+    uint16_t addr;
+    enum AtmegaPeripheral power_index;
+    uint8_t power_bit;
+    /* timer specific */
+    uint16_t intmask_addr;
+    uint16_t intflag_addr;
+    bool is_timer16;
+} peripheral_cfg;
+
+typedef struct AtmegaMcuClass {
+    /*< private >*/
+    SysBusDeviceClass parent_class;
+    /*< public >*/
+    const char *uc_name;
+    const char *cpu_type;
+    size_t flash_size;
+    size_t eeprom_size;
+    size_t sram_size;
+    size_t io_size;
+    size_t gpio_count;
+    size_t adc_count;
+    const uint8_t *irq;
+    const peripheral_cfg *dev;
+} AtmegaMcuClass;
+
+#define ATMEGA_MCU_CLASS(klass) \
+    OBJECT_CLASS_CHECK(AtmegaMcuClass, (klass), TYPE_ATMEGA_MCU)
+#define ATMEGA_MCU_GET_CLASS(obj) \
+    OBJECT_GET_CLASS(AtmegaMcuClass, (obj), TYPE_ATMEGA_MCU)
+
+static const peripheral_cfg dev168_328[PERIFMAX] = {
+    [USART0]        = {  0xc0, POWER0, 1 },
+    [TIMER2]        = {  0xb0, POWER0, 6, 0x70, 0x37, false },
+    [TIMER1]        = {  0x80, POWER0, 3, 0x6f, 0x36, true },
+    [POWER0]        = {  0x64 },
+    [TIMER0]        = {  0x44, POWER0, 5, 0x6e, 0x35, false },
+    [GPIOD]         = {  0x29 },
+    [GPIOC]         = {  0x26 },
+    [GPIOB]         = {  0x23 },
+}, dev1280_2560[PERIFMAX] = {
+    [USART3]        = { 0x130, POWER1, 2 },
+    [TIMER5]        = { 0x120, POWER1, 5, 0x73, 0x3a, true },
+    [GPIOL]         = { 0x109 },
+    [GPIOK]         = { 0x106 },
+    [GPIOJ]         = { 0x103 },
+    [GPIOH]         = { 0x100 },
+    [USART2]        = {  0xd0, POWER1, 1 },
+    [USART1]        = {  0xc8, POWER1, 0 },
+    [USART0]        = {  0xc0, POWER0, 1 },
+    [TIMER2]        = {  0xb0, POWER0, 6, 0x70, 0x37, false }, /* TODO async */
+    [TIMER4]        = {  0xa0, POWER1, 4, 0x72, 0x39, true },
+    [TIMER3]        = {  0x90, POWER1, 3, 0x71, 0x38, true },
+    [TIMER1]        = {  0x80, POWER0, 3, 0x6f, 0x36, true },
+    [POWER1]        = {  0x65 },
+    [POWER0]        = {  0x64 },
+    [TIMER0]        = {  0x44, POWER0, 5, 0x6e, 0x35, false },
+    [GPIOG]         = {  0x32 },
+    [GPIOF]         = {  0x2f },
+    [GPIOE]         = {  0x2c },
+    [GPIOD]         = {  0x29 },
+    [GPIOC]         = {  0x26 },
+    [GPIOB]         = {  0x23 },
+    [GPIOA]         = {  0x20 },
+};
+
+enum AtmegaIrq {
+    USART0_RXC_IRQ, USART0_DRE_IRQ, USART0_TXC_IRQ,
+    USART1_RXC_IRQ, USART1_DRE_IRQ, USART1_TXC_IRQ,
+    USART2_RXC_IRQ, USART2_DRE_IRQ, USART2_TXC_IRQ,
+    USART3_RXC_IRQ, USART3_DRE_IRQ, USART3_TXC_IRQ,
+    TIMER0_CAPT_IRQ, TIMER0_COMPA_IRQ, TIMER0_COMPB_IRQ,
+        TIMER0_COMPC_IRQ, TIMER0_OVF_IRQ,
+    TIMER1_CAPT_IRQ, TIMER1_COMPA_IRQ, TIMER1_COMPB_IRQ,
+        TIMER1_COMPC_IRQ, TIMER1_OVF_IRQ,
+    TIMER2_CAPT_IRQ, TIMER2_COMPA_IRQ, TIMER2_COMPB_IRQ,
+        TIMER2_COMPC_IRQ, TIMER2_OVF_IRQ,
+    TIMER3_CAPT_IRQ, TIMER3_COMPA_IRQ, TIMER3_COMPB_IRQ,
+        TIMER3_COMPC_IRQ, TIMER3_OVF_IRQ,
+    TIMER4_CAPT_IRQ, TIMER4_COMPA_IRQ, TIMER4_COMPB_IRQ,
+        TIMER4_COMPC_IRQ, TIMER4_OVF_IRQ,
+    TIMER5_CAPT_IRQ, TIMER5_COMPA_IRQ, TIMER5_COMPB_IRQ,
+        TIMER5_COMPC_IRQ, TIMER5_OVF_IRQ,
+    IRQ_COUNT
+};
+
+#define USART_IRQ_COUNT     3
+#define USART_RXC_IRQ(n)    (n * USART_IRQ_COUNT + USART0_RXC_IRQ)
+#define USART_DRE_IRQ(n)    (n * USART_IRQ_COUNT + USART0_DRE_IRQ)
+#define USART_TXC_IRQ(n)    (n * USART_IRQ_COUNT + USART0_TXC_IRQ)
+#define TIMER_IRQ_COUNT     5
+#define TIMER_CAPT_IRQ(n)   (n * TIMER_IRQ_COUNT + TIMER0_CAPT_IRQ)
+#define TIMER_COMPA_IRQ(n)  (n * TIMER_IRQ_COUNT + TIMER0_COMPA_IRQ)
+#define TIMER_COMPB_IRQ(n)  (n * TIMER_IRQ_COUNT + TIMER0_COMPB_IRQ)
+#define TIMER_COMPC_IRQ(n)  (n * TIMER_IRQ_COUNT + TIMER0_COMPC_IRQ)
+#define TIMER_OVF_IRQ(n)    (n * TIMER_IRQ_COUNT + TIMER0_OVF_IRQ)
+
+static const uint8_t irq168_328[IRQ_COUNT] = {
+    [TIMER2_COMPA_IRQ]      = 8,
+    [TIMER2_COMPB_IRQ]      = 9,
+    [TIMER2_OVF_IRQ]        = 10,
+    [TIMER1_CAPT_IRQ]       = 11,
+    [TIMER1_COMPA_IRQ]      = 12,
+    [TIMER1_COMPB_IRQ]      = 13,
+    [TIMER1_OVF_IRQ]        = 14,
+    [TIMER0_COMPA_IRQ]      = 15,
+    [TIMER0_COMPB_IRQ]      = 16,
+    [TIMER0_OVF_IRQ]        = 17,
+    [USART0_RXC_IRQ]        = 19,
+    [USART0_DRE_IRQ]        = 20,
+    [USART0_TXC_IRQ]        = 21,
+}, irq1280_2560[IRQ_COUNT] = {
+    [TIMER2_COMPA_IRQ]      = 14,
+    [TIMER2_COMPB_IRQ]      = 15,
+    [TIMER2_OVF_IRQ]        = 16,
+    [TIMER1_CAPT_IRQ]       = 17,
+    [TIMER1_COMPA_IRQ]      = 18,
+    [TIMER1_COMPB_IRQ]      = 19,
+    [TIMER1_COMPC_IRQ]      = 20,
+    [TIMER1_OVF_IRQ]        = 21,
+    [TIMER0_COMPA_IRQ]      = 22,
+    [TIMER0_COMPB_IRQ]      = 23,
+    [TIMER0_OVF_IRQ]        = 24,
+    [USART0_RXC_IRQ]        = 26,
+    [USART0_DRE_IRQ]        = 27,
+    [USART0_TXC_IRQ]        = 28,
+    [TIMER3_CAPT_IRQ]       = 32,
+    [TIMER3_COMPA_IRQ]      = 33,
+    [TIMER3_COMPB_IRQ]      = 34,
+    [TIMER3_COMPC_IRQ]      = 35,
+    [TIMER3_OVF_IRQ]        = 36,
+    [USART1_RXC_IRQ]        = 37,
+    [USART1_DRE_IRQ]        = 38,
+    [USART1_TXC_IRQ]        = 39,
+    [TIMER4_CAPT_IRQ]       = 42,
+    [TIMER4_COMPA_IRQ]      = 43,
+    [TIMER4_COMPB_IRQ]      = 44,
+    [TIMER4_COMPC_IRQ]      = 45,
+    [TIMER4_OVF_IRQ]        = 46,
+    [TIMER5_CAPT_IRQ]       = 47,
+    [TIMER5_COMPA_IRQ]      = 48,
+    [TIMER5_COMPB_IRQ]      = 49,
+    [TIMER5_COMPC_IRQ]      = 50,
+    [TIMER5_OVF_IRQ]        = 51,
+    [USART2_RXC_IRQ]        = 52,
+    [USART2_DRE_IRQ]        = 53,
+    [USART2_TXC_IRQ]        = 54,
+    [USART3_RXC_IRQ]        = 55,
+    [USART3_DRE_IRQ]        = 56,
+    [USART3_TXC_IRQ]        = 57,
+};
+
+static void connect_peripheral_irq(const AtmegaMcuClass *k,
+                                   SysBusDevice *dev, int dev_irqn,
+                                   DeviceState *cpu,
+                                   unsigned peripheral_index)
+{
+    int cpu_irq = k->irq[peripheral_index];
+
+    if (!cpu_irq) {
+        return;
+    }
+    /* FIXME move that to avr_cpu_set_int() once 'sample' board is removed */
+    assert(cpu_irq >= 2);
+    cpu_irq -= 2;
+
+    sysbus_connect_irq(dev, dev_irqn, qdev_get_gpio_in(cpu, cpu_irq));
+}
+
+static void connect_power_reduction_gpio(AtmegaMcuState *s,
+                                         const AtmegaMcuClass *k,
+                                         DeviceState *cpu,
+                                         unsigned peripheral_index)
+{
+    unsigned power_index = k->dev[peripheral_index].power_index;
+    assert(k->dev[power_index].addr);
+    sysbus_connect_irq(SYS_BUS_DEVICE(&s->pwr[power_index - POWER0]),
+                       k->dev[peripheral_index].power_bit,
+                       qdev_get_gpio_in(cpu, 0));
+}
+
+static void atmega_realize(DeviceState *dev, Error **errp)
+{
+    AtmegaMcuState *s = ATMEGA_MCU(dev);
+    const AtmegaMcuClass *mc = ATMEGA_MCU_GET_CLASS(dev);
+    DeviceState *cpudev;
+    SysBusDevice *sbd;
+    char *devname;
+    size_t i;
+
+    assert(mc->io_size <= 0x200);
+
+    if (!s->xtal_freq_hz) {
+        error_setg(errp, "\"xtal-frequency-hz\" property must be provided.");
+        return;
+    }
+
+    /* CPU */
+    object_initialize_child(OBJECT(dev), "cpu", &s->cpu, mc->cpu_type);
+    object_property_set_bool(OBJECT(&s->cpu), "realized", true, &error_abort);
+    cpudev = DEVICE(&s->cpu);
+
+    /* SRAM */
+    memory_region_init_ram(&s->sram, OBJECT(dev), "sram", mc->sram_size,
+                           &error_abort);
+    memory_region_add_subregion(get_system_memory(),
+                                OFFSET_DATA + mc->io_size, &s->sram);
+
+    /* Flash */
+    memory_region_init_rom(&s->flash, OBJECT(dev),
+                           "flash", mc->flash_size, &error_fatal);
+    memory_region_add_subregion(get_system_memory(), OFFSET_CODE, &s->flash);
+
+    /*
+     * I/O
+     *
+     * 0x00 - 0x1f: Registers
+     * 0x20 - 0x5f: I/O memory
+     * 0x60 - 0xff: Extended I/O
+     */
+    s->io = qdev_new(TYPE_UNIMPLEMENTED_DEVICE);
+    qdev_prop_set_string(s->io, "name", "I/O");
+    qdev_prop_set_uint64(s->io, "size", mc->io_size);
+    sysbus_realize_and_unref(SYS_BUS_DEVICE(s->io), &error_fatal);
+    sysbus_mmio_map_overlap(SYS_BUS_DEVICE(s->io), 0, OFFSET_DATA, -1234);
+
+    /* Power Reduction */
+    for (i = 0; i < POWER_MAX; i++) {
+        int idx = POWER(i);
+        if (!mc->dev[idx].addr) {
+            continue;
+        }
+        devname = g_strdup_printf("power%zu", i);
+        object_initialize_child(OBJECT(dev), devname, &s->pwr[i],
+                                TYPE_AVR_MASK);
+        sysbus_realize(SYS_BUS_DEVICE(&s->pwr[i]), &error_abort);
+        sysbus_mmio_map(SYS_BUS_DEVICE(&s->pwr[i]), 0,
+                        OFFSET_DATA + mc->dev[idx].addr);
+        g_free(devname);
+    }
+
+    /* GPIO */
+    for (i = 0; i < GPIO_MAX; i++) {
+        int idx = GPIO(i);
+        if (!mc->dev[idx].addr) {
+            continue;
+        }
+        devname = g_strdup_printf("atmega-gpio-%c", 'a' + (char)i);
+        create_unimplemented_device(devname,
+                                    OFFSET_DATA + mc->dev[idx].addr, 3);
+        g_free(devname);
+    }
+
+    /* USART */
+    for (i = 0; i < USART_MAX; i++) {
+        int idx = USART(i);
+        if (!mc->dev[idx].addr) {
+            continue;
+        }
+        devname = g_strdup_printf("usart%zu", i);
+        object_initialize_child(OBJECT(dev), devname, &s->usart[i],
+                                TYPE_AVR_USART);
+        qdev_prop_set_chr(DEVICE(&s->usart[i]), "chardev", serial_hd(i));
+        sbd = SYS_BUS_DEVICE(&s->usart[i]);
+        sysbus_realize(sbd, &error_abort);
+        sysbus_mmio_map(sbd, 0, OFFSET_DATA + mc->dev[USART(i)].addr);
+        connect_peripheral_irq(mc, sbd, 0, cpudev, USART_RXC_IRQ(i));
+        connect_peripheral_irq(mc, sbd, 1, cpudev, USART_DRE_IRQ(i));
+        connect_peripheral_irq(mc, sbd, 2, cpudev, USART_TXC_IRQ(i));
+        connect_power_reduction_gpio(s, mc, DEVICE(&s->usart[i]), idx);
+        g_free(devname);
+    }
+
+    /* Timer */
+    for (i = 0; i < TIMER_MAX; i++) {
+        int idx = TIMER(i);
+        if (!mc->dev[idx].addr) {
+            continue;
+        }
+        if (!mc->dev[idx].is_timer16) {
+            create_unimplemented_device("avr-timer8",
+                                        OFFSET_DATA + mc->dev[idx].addr, 5);
+            create_unimplemented_device("avr-timer8-intmask",
+                                        OFFSET_DATA
+                                        + mc->dev[idx].intmask_addr, 1);
+            create_unimplemented_device("avr-timer8-intflag",
+                                        OFFSET_DATA
+                                        + mc->dev[idx].intflag_addr, 1);
+            continue;
+        }
+        devname = g_strdup_printf("timer%zu", i);
+        object_initialize_child(OBJECT(dev), devname, &s->timer[i],
+                                TYPE_AVR_TIMER16);
+        object_property_set_uint(OBJECT(&s->timer[i]), "cpu-frequency-hz",
+                                 s->xtal_freq_hz, &error_abort);
+        sbd = SYS_BUS_DEVICE(&s->timer[i]);
+        sysbus_realize(sbd, &error_abort);
+        sysbus_mmio_map(sbd, 0, OFFSET_DATA + mc->dev[idx].addr);
+        sysbus_mmio_map(sbd, 1, OFFSET_DATA + mc->dev[idx].intmask_addr);
+        sysbus_mmio_map(sbd, 2, OFFSET_DATA + mc->dev[idx].intflag_addr);
+        connect_peripheral_irq(mc, sbd, 0, cpudev, TIMER_CAPT_IRQ(i));
+        connect_peripheral_irq(mc, sbd, 1, cpudev, TIMER_COMPA_IRQ(i));
+        connect_peripheral_irq(mc, sbd, 2, cpudev, TIMER_COMPB_IRQ(i));
+        connect_peripheral_irq(mc, sbd, 3, cpudev, TIMER_COMPC_IRQ(i));
+        connect_peripheral_irq(mc, sbd, 4, cpudev, TIMER_OVF_IRQ(i));
+        connect_power_reduction_gpio(s, mc, DEVICE(&s->timer[i]), idx);
+        g_free(devname);
+    }
+
+    create_unimplemented_device("avr-twi",          OFFSET_DATA + 0x0b8, 6);
+    create_unimplemented_device("avr-adc",          OFFSET_DATA + 0x078, 8);
+    create_unimplemented_device("avr-ext-mem-ctrl", OFFSET_DATA + 0x074, 2);
+    create_unimplemented_device("avr-watchdog",     OFFSET_DATA + 0x060, 1);
+    create_unimplemented_device("avr-spi",          OFFSET_DATA + 0x04c, 3);
+    create_unimplemented_device("avr-eeprom",       OFFSET_DATA + 0x03f, 3);
+}
+
+static Property atmega_props[] = {
+    DEFINE_PROP_UINT64("xtal-frequency-hz", AtmegaMcuState,
+                       xtal_freq_hz, 0),
+    DEFINE_PROP_END_OF_LIST()
+};
+
+static void atmega_class_init(ObjectClass *oc, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(oc);
+
+    dc->realize = atmega_realize;
+    device_class_set_props(dc, atmega_props);
+    /* Reason: Mapped at fixed location on the system bus */
+    dc->user_creatable = false;
+}
+
+static void atmega168_class_init(ObjectClass *oc, void *data)
+{
+    AtmegaMcuClass *amc = ATMEGA_MCU_CLASS(oc);
+
+    amc->cpu_type = AVR_CPU_TYPE_NAME("avr5");
+    amc->flash_size = 16 * KiB;
+    amc->eeprom_size = 512;
+    amc->sram_size = 1 * KiB;
+    amc->io_size = 256;
+    amc->gpio_count = 23;
+    amc->adc_count = 6;
+    amc->irq = irq168_328;
+    amc->dev = dev168_328;
+};
+
+static void atmega328_class_init(ObjectClass *oc, void *data)
+{
+    AtmegaMcuClass *amc = ATMEGA_MCU_CLASS(oc);
+
+    amc->cpu_type = AVR_CPU_TYPE_NAME("avr5");
+    amc->flash_size = 32 * KiB;
+    amc->eeprom_size = 1 * KiB;
+    amc->sram_size = 2 * KiB;
+    amc->io_size = 256;
+    amc->gpio_count = 23;
+    amc->adc_count = 6;
+    amc->irq = irq168_328;
+    amc->dev = dev168_328;
+};
+
+static void atmega1280_class_init(ObjectClass *oc, void *data)
+{
+    AtmegaMcuClass *amc = ATMEGA_MCU_CLASS(oc);
+
+    amc->cpu_type = AVR_CPU_TYPE_NAME("avr6");
+    amc->flash_size = 128 * KiB;
+    amc->eeprom_size = 4 * KiB;
+    amc->sram_size = 8 * KiB;
+    amc->io_size = 512;
+    amc->gpio_count = 86;
+    amc->adc_count = 16;
+    amc->irq = irq1280_2560;
+    amc->dev = dev1280_2560;
+};
+
+static void atmega2560_class_init(ObjectClass *oc, void *data)
+{
+    AtmegaMcuClass *amc = ATMEGA_MCU_CLASS(oc);
+
+    amc->cpu_type = AVR_CPU_TYPE_NAME("avr6");
+    amc->flash_size = 256 * KiB;
+    amc->eeprom_size = 4 * KiB;
+    amc->sram_size = 8 * KiB;
+    amc->io_size = 512;
+    amc->gpio_count = 54;
+    amc->adc_count = 16;
+    amc->irq = irq1280_2560;
+    amc->dev = dev1280_2560;
+};
+
+static const TypeInfo atmega_mcu_types[] = {
+    {
+        .name           = TYPE_ATMEGA168_MCU,
+        .parent         = TYPE_ATMEGA_MCU,
+        .class_init     = atmega168_class_init,
+    }, {
+        .name           = TYPE_ATMEGA328_MCU,
+        .parent         = TYPE_ATMEGA_MCU,
+        .class_init     = atmega328_class_init,
+    }, {
+        .name           = TYPE_ATMEGA1280_MCU,
+        .parent         = TYPE_ATMEGA_MCU,
+        .class_init     = atmega1280_class_init,
+    }, {
+        .name           = TYPE_ATMEGA2560_MCU,
+        .parent         = TYPE_ATMEGA_MCU,
+        .class_init     = atmega2560_class_init,
+    }, {
+        .name           = TYPE_ATMEGA_MCU,
+        .parent         = TYPE_SYS_BUS_DEVICE,
+        .instance_size  = sizeof(AtmegaMcuState),
+        .class_size     = sizeof(AtmegaMcuClass),
+        .class_init     = atmega_class_init,
+        .abstract       = true,
+    }
+};
+
+DEFINE_TYPES(atmega_mcu_types)
diff --git a/hw/avr/atmega.h b/hw/avr/atmega.h
new file mode 100644
index 0000000000..0928cb0ce6
--- /dev/null
+++ b/hw/avr/atmega.h
@@ -0,0 +1,48 @@
+/*
+ * QEMU ATmega MCU
+ *
+ * Copyright (c) 2019-2020 Philippe Mathieu-Daudé
+ *
+ * This work is licensed under the terms of the GNU GPLv2 or later.
+ * See the COPYING file in the top-level directory.
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#ifndef HW_AVR_ATMEGA_H
+#define HW_AVR_ATMEGA_H
+
+#include "hw/char/avr_usart.h"
+#include "hw/timer/avr_timer16.h"
+#include "hw/misc/avr_power.h"
+#include "target/avr/cpu.h"
+
+#define TYPE_ATMEGA_MCU     "ATmega"
+#define TYPE_ATMEGA168_MCU  "ATmega168"
+#define TYPE_ATMEGA328_MCU  "ATmega328"
+#define TYPE_ATMEGA1280_MCU "ATmega1280"
+#define TYPE_ATMEGA2560_MCU "ATmega2560"
+
+#define ATMEGA_MCU(obj) OBJECT_CHECK(AtmegaMcuState, (obj), TYPE_ATMEGA_MCU)
+
+#define POWER_MAX 2
+#define USART_MAX 4
+#define TIMER_MAX 6
+#define GPIO_MAX 12
+
+typedef struct AtmegaMcuState {
+    /*< private >*/
+    SysBusDevice parent_obj;
+    /*< public >*/
+
+    AVRCPU cpu;
+    MemoryRegion flash;
+    MemoryRegion eeprom;
+    MemoryRegion sram;
+    DeviceState *io;
+    AVRMaskState pwr[POWER_MAX];
+    AVRUsartState usart[USART_MAX];
+    AVRTimer16State timer[TIMER_MAX];
+    uint64_t xtal_freq_hz;
+} AtmegaMcuState;
+
+#endif /* HW_AVR_ATMEGA_H */
diff --git a/hw/avr/boot.c b/hw/avr/boot.c
new file mode 100644
index 0000000000..6fbcde4061
--- /dev/null
+++ b/hw/avr/boot.c
@@ -0,0 +1,115 @@
+/*
+ * AVR loader helpers
+ *
+ * Copyright (c) 2019-2020 Philippe Mathieu-Daudé
+ *
+ * This work is licensed under the terms of the GNU GPLv2 or later.
+ * See the COPYING file in the top-level directory.
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "qemu/osdep.h"
+#include "qemu-common.h"
+#include "hw/loader.h"
+#include "elf.h"
+#include "boot.h"
+#include "qemu/error-report.h"
+
+static const char *avr_elf_e_flags_to_cpu_type(uint32_t flags)
+{
+    switch (flags & EF_AVR_MACH) {
+    case bfd_mach_avr1:
+        return AVR_CPU_TYPE_NAME("avr1");
+    case bfd_mach_avr2:
+        return AVR_CPU_TYPE_NAME("avr2");
+    case bfd_mach_avr25:
+        return AVR_CPU_TYPE_NAME("avr25");
+    case bfd_mach_avr3:
+        return AVR_CPU_TYPE_NAME("avr3");
+    case bfd_mach_avr31:
+        return AVR_CPU_TYPE_NAME("avr31");
+    case bfd_mach_avr35:
+        return AVR_CPU_TYPE_NAME("avr35");
+    case bfd_mach_avr4:
+        return AVR_CPU_TYPE_NAME("avr4");
+    case bfd_mach_avr5:
+        return AVR_CPU_TYPE_NAME("avr5");
+    case bfd_mach_avr51:
+        return AVR_CPU_TYPE_NAME("avr51");
+    case bfd_mach_avr6:
+        return AVR_CPU_TYPE_NAME("avr6");
+    case bfd_mach_avrtiny:
+        return AVR_CPU_TYPE_NAME("avrtiny");
+    case bfd_mach_avrxmega2:
+        return AVR_CPU_TYPE_NAME("xmega2");
+    case bfd_mach_avrxmega3:
+        return AVR_CPU_TYPE_NAME("xmega3");
+    case bfd_mach_avrxmega4:
+        return AVR_CPU_TYPE_NAME("xmega4");
+    case bfd_mach_avrxmega5:
+        return AVR_CPU_TYPE_NAME("xmega5");
+    case bfd_mach_avrxmega6:
+        return AVR_CPU_TYPE_NAME("xmega6");
+    case bfd_mach_avrxmega7:
+        return AVR_CPU_TYPE_NAME("xmega7");
+    default:
+        return NULL;
+    }
+}
+
+bool avr_load_firmware(AVRCPU *cpu, MachineState *ms,
+                       MemoryRegion *program_mr, const char *firmware)
+{
+    const char *filename;
+    int bytes_loaded;
+    uint64_t entry;
+    uint32_t e_flags;
+
+    filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, firmware);
+    if (filename == NULL) {
+        error_report("Unable to find %s", firmware);
+        return false;
+    }
+
+    bytes_loaded = load_elf_ram_sym(filename,
+                                    NULL, NULL, NULL,
+                                    &entry, NULL, NULL,
+                                    &e_flags, 0, EM_AVR, 0, 0,
+                                    NULL, true, NULL);
+    if (bytes_loaded >= 0) {
+        /* If ELF file is provided, determine CPU type reading ELF e_flags. */
+        const char *elf_cpu = avr_elf_e_flags_to_cpu_type(e_flags);
+        const char *mcu_cpu_type = object_get_typename(OBJECT(cpu));
+        int cpu_len = strlen(mcu_cpu_type) - strlen(AVR_CPU_TYPE_SUFFIX);
+
+        if (entry) {
+            error_report("BIOS entry_point must be 0x0000 "
+                         "(ELF image '%s' has entry_point 0x%04" PRIx64 ")",
+                         firmware, entry);
+            return false;
+        }
+        if (!elf_cpu) {
+            warn_report("Could not determine CPU type for ELF image '%s', "
+                        "assuming '%.*s' CPU",
+                         firmware, cpu_len, mcu_cpu_type);
+            return true;
+        }
+        if (strcmp(elf_cpu, mcu_cpu_type)) {
+            error_report("Current machine: %s with '%.*s' CPU",
+                         MACHINE_GET_CLASS(ms)->desc, cpu_len, mcu_cpu_type);
+            error_report("ELF image '%s' is for '%.*s' CPU",
+                         firmware,
+                         (int)(strlen(elf_cpu) - strlen(AVR_CPU_TYPE_SUFFIX)),
+                         elf_cpu);
+            return false;
+        }
+    } else {
+        bytes_loaded = load_image_mr(filename, program_mr);
+    }
+    if (bytes_loaded < 0) {
+        error_report("Unable to load firmware image %s as ELF or raw binary",
+                     firmware);
+        return false;
+    }
+    return true;
+}
diff --git a/hw/avr/boot.h b/hw/avr/boot.h
new file mode 100644
index 0000000000..684d553322
--- /dev/null
+++ b/hw/avr/boot.h
@@ -0,0 +1,33 @@
+/*
+ * AVR loader helpers
+ *
+ * Copyright (c) 2019-2020 Philippe Mathieu-Daudé
+ *
+ * This work is licensed under the terms of the GNU GPLv2 or later.
+ * See the COPYING file in the top-level directory.
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#ifndef HW_AVR_BOOT_H
+#define HW_AVR_BOOT_H
+
+#include "hw/boards.h"
+#include "cpu.h"
+
+/**
+ * avr_load_firmware:   load an image into a memory region
+ *
+ * @cpu:        Handle a AVR CPU object
+ * @ms:         A MachineState
+ * @mr:         Memory Region to load into
+ * @firmware:   Path to the firmware file (raw binary or ELF format)
+ *
+ * Load a firmware supplied by the machine or by the user  with the
+ * '-bios' command line option, and put it in target memory.
+ *
+ * Returns: true on success, false on error.
+ */
+bool avr_load_firmware(AVRCPU *cpu, MachineState *ms,
+                       MemoryRegion *mr, const char *firmware);
+
+#endif
diff --git a/hw/char/Kconfig b/hw/char/Kconfig
index 874627520c..b7e0e4d5fa 100644
--- a/hw/char/Kconfig
+++ b/hw/char/Kconfig
@@ -49,3 +49,6 @@ config TERMINAL3270
 
 config RENESAS_SCI
     bool
+
+config AVR_USART
+    bool
diff --git a/hw/char/Makefile.objs b/hw/char/Makefile.objs
index 8306c4a789..bf177ac41d 100644
--- a/hw/char/Makefile.objs
+++ b/hw/char/Makefile.objs
@@ -22,6 +22,7 @@ common-obj-$(CONFIG_DIGIC) += digic-uart.o
 common-obj-$(CONFIG_STM32F2XX_USART) += stm32f2xx_usart.o
 common-obj-$(CONFIG_RASPI) += bcm2835_aux.o
 common-obj-$(CONFIG_RENESAS_SCI) += renesas_sci.o
+common-obj-$(CONFIG_AVR_USART) += avr_usart.o
 
 common-obj-$(CONFIG_CMSDK_APB_UART) += cmsdk-apb-uart.o
 common-obj-$(CONFIG_ETRAXFS) += etraxfs_ser.o
diff --git a/hw/char/avr_usart.c b/hw/char/avr_usart.c
new file mode 100644
index 0000000000..fbe2a112b7
--- /dev/null
+++ b/hw/char/avr_usart.c
@@ -0,0 +1,320 @@
+/*
+ * AVR USART
+ *
+ * Copyright (c) 2018 University of Kent
+ * Author: Sarah Harris
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see
+ * <http://www.gnu.org/licenses/lgpl-2.1.html>
+ */
+
+#include "qemu/osdep.h"
+#include "hw/char/avr_usart.h"
+#include "qemu/log.h"
+#include "hw/irq.h"
+#include "hw/qdev-properties.h"
+
+static int avr_usart_can_receive(void *opaque)
+{
+    AVRUsartState *usart = opaque;
+
+    if (usart->data_valid || !(usart->csrb & USART_CSRB_RXEN)) {
+        return 0;
+    }
+    return 1;
+}
+
+static void avr_usart_receive(void *opaque, const uint8_t *buffer, int size)
+{
+    AVRUsartState *usart = opaque;
+    assert(size == 1);
+    assert(!usart->data_valid);
+    usart->data = buffer[0];
+    usart->data_valid = true;
+    usart->csra |= USART_CSRA_RXC;
+    if (usart->csrb & USART_CSRB_RXCIE) {
+        qemu_set_irq(usart->rxc_irq, 1);
+    }
+}
+
+static void update_char_mask(AVRUsartState *usart)
+{
+    uint8_t mode = ((usart->csrc & USART_CSRC_CSZ0) ? 1 : 0) |
+        ((usart->csrc & USART_CSRC_CSZ1) ? 2 : 0) |
+        ((usart->csrb & USART_CSRB_CSZ2) ? 4 : 0);
+    switch (mode) {
+    case 0:
+        usart->char_mask = 0b11111;
+        break;
+    case 1:
+        usart->char_mask = 0b111111;
+        break;
+    case 2:
+        usart->char_mask = 0b1111111;
+        break;
+    case 3:
+        usart->char_mask = 0b11111111;
+        break;
+    case 4:
+        /* Fallthrough. */
+    case 5:
+        /* Fallthrough. */
+    case 6:
+        qemu_log_mask(
+            LOG_GUEST_ERROR,
+            "%s: Reserved character size 0x%x\n",
+            __func__,
+            mode);
+        break;
+    case 7:
+        qemu_log_mask(
+            LOG_GUEST_ERROR,
+            "%s: Nine bit character size not supported (forcing eight)\n",
+            __func__);
+        usart->char_mask = 0b11111111;
+        break;
+    default:
+        assert(0);
+    }
+}
+
+static void avr_usart_reset(DeviceState *dev)
+{
+    AVRUsartState *usart = AVR_USART(dev);
+    usart->data_valid = false;
+    usart->csra = 0b00100000;
+    usart->csrb = 0b00000000;
+    usart->csrc = 0b00000110;
+    usart->brrl = 0;
+    usart->brrh = 0;
+    update_char_mask(usart);
+    qemu_set_irq(usart->rxc_irq, 0);
+    qemu_set_irq(usart->txc_irq, 0);
+    qemu_set_irq(usart->dre_irq, 0);
+}
+
+static uint64_t avr_usart_read(void *opaque, hwaddr addr, unsigned int size)
+{
+    AVRUsartState *usart = opaque;
+    uint8_t data;
+    assert(size == 1);
+
+    if (!usart->enabled) {
+        return 0;
+    }
+
+    switch (addr) {
+    case USART_DR:
+        if (!(usart->csrb & USART_CSRB_RXEN)) {
+            /* Receiver disabled, ignore. */
+            return 0;
+        }
+        if (usart->data_valid) {
+            data = usart->data & usart->char_mask;
+            usart->data_valid = false;
+        } else {
+            data = 0;
+        }
+        usart->csra &= 0xff ^ USART_CSRA_RXC;
+        qemu_set_irq(usart->rxc_irq, 0);
+        qemu_chr_fe_accept_input(&usart->chr);
+        return data;
+    case USART_CSRA:
+        return usart->csra;
+    case USART_CSRB:
+        return usart->csrb;
+    case USART_CSRC:
+        return usart->csrc;
+    case USART_BRRL:
+        return usart->brrl;
+    case USART_BRRH:
+        return usart->brrh;
+    default:
+        qemu_log_mask(
+            LOG_GUEST_ERROR,
+            "%s: Bad offset 0x%"HWADDR_PRIx"\n",
+            __func__,
+            addr);
+    }
+    return 0;
+}
+
+static void avr_usart_write(void *opaque, hwaddr addr, uint64_t value,
+                                unsigned int size)
+{
+    AVRUsartState *usart = opaque;
+    uint8_t mask;
+    uint8_t data;
+    assert((value & 0xff) == value);
+    assert(size == 1);
+
+    if (!usart->enabled) {
+        return;
+    }
+
+    switch (addr) {
+    case USART_DR:
+        if (!(usart->csrb & USART_CSRB_TXEN)) {
+            /* Transmitter disabled, ignore. */
+            return;
+        }
+        usart->csra |= USART_CSRA_TXC;
+        usart->csra |= USART_CSRA_DRE;
+        if (usart->csrb & USART_CSRB_TXCIE) {
+            qemu_set_irq(usart->txc_irq, 1);
+            usart->csra &= 0xff ^ USART_CSRA_TXC;
+        }
+        if (usart->csrb & USART_CSRB_DREIE) {
+            qemu_set_irq(usart->dre_irq, 1);
+        }
+        data = value;
+        qemu_chr_fe_write_all(&usart->chr, &data, 1);
+        break;
+    case USART_CSRA:
+        mask = 0b01000011;
+        /* Mask read-only bits. */
+        value = (value & mask) | (usart->csra & (0xff ^ mask));
+        usart->csra = value;
+        if (value & USART_CSRA_TXC) {
+            usart->csra ^= USART_CSRA_TXC;
+            qemu_set_irq(usart->txc_irq, 0);
+        }
+        if (value & USART_CSRA_MPCM) {
+            qemu_log_mask(
+                LOG_GUEST_ERROR,
+                "%s: MPCM not supported by USART\n",
+                __func__);
+        }
+        break;
+    case USART_CSRB:
+        mask = 0b11111101;
+        /* Mask read-only bits. */
+        value = (value & mask) | (usart->csrb & (0xff ^ mask));
+        usart->csrb = value;
+        if (!(value & USART_CSRB_RXEN)) {
+            /* Receiver disabled, flush input buffer. */
+            usart->data_valid = false;
+        }
+        qemu_set_irq(usart->rxc_irq,
+            ((value & USART_CSRB_RXCIE) &&
+            (usart->csra & USART_CSRA_RXC)) ? 1 : 0);
+        qemu_set_irq(usart->txc_irq,
+            ((value & USART_CSRB_TXCIE) &&
+            (usart->csra & USART_CSRA_TXC)) ? 1 : 0);
+        qemu_set_irq(usart->dre_irq,
+            ((value & USART_CSRB_DREIE) &&
+            (usart->csra & USART_CSRA_DRE)) ? 1 : 0);
+        update_char_mask(usart);
+        break;
+    case USART_CSRC:
+        usart->csrc = value;
+        if ((value & USART_CSRC_MSEL1) && (value & USART_CSRC_MSEL0)) {
+            qemu_log_mask(
+                LOG_GUEST_ERROR,
+                "%s: SPI mode not supported by USART\n",
+                __func__);
+        }
+        if ((value & USART_CSRC_MSEL1) && !(value & USART_CSRC_MSEL0)) {
+            qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad USART mode\n", __func__);
+        }
+        if (!(value & USART_CSRC_PM1) && (value & USART_CSRC_PM0)) {
+            qemu_log_mask(
+                LOG_GUEST_ERROR,
+                "%s: Bad USART parity mode\n",
+                __func__);
+        }
+        update_char_mask(usart);
+        break;
+    case USART_BRRL:
+        usart->brrl = value;
+        break;
+    case USART_BRRH:
+        usart->brrh = value & 0b00001111;
+        break;
+    default:
+        qemu_log_mask(
+            LOG_GUEST_ERROR,
+            "%s: Bad offset 0x%"HWADDR_PRIx"\n",
+            __func__,
+            addr);
+    }
+}
+
+static const MemoryRegionOps avr_usart_ops = {
+    .read = avr_usart_read,
+    .write = avr_usart_write,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+    .impl = {.min_access_size = 1, .max_access_size = 1}
+};
+
+static Property avr_usart_properties[] = {
+    DEFINE_PROP_CHR("chardev", AVRUsartState, chr),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static void avr_usart_pr(void *opaque, int irq, int level)
+{
+    AVRUsartState *s = AVR_USART(opaque);
+
+    s->enabled = !level;
+
+    if (!s->enabled) {
+        avr_usart_reset(DEVICE(s));
+    }
+}
+
+static void avr_usart_init(Object *obj)
+{
+    AVRUsartState *s = AVR_USART(obj);
+    sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->rxc_irq);
+    sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->dre_irq);
+    sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->txc_irq);
+    memory_region_init_io(&s->mmio, obj, &avr_usart_ops, s, TYPE_AVR_USART, 7);
+    sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->mmio);
+    qdev_init_gpio_in(DEVICE(s), avr_usart_pr, 1);
+    s->enabled = true;
+}
+
+static void avr_usart_realize(DeviceState *dev, Error **errp)
+{
+    AVRUsartState *s = AVR_USART(dev);
+    qemu_chr_fe_set_handlers(&s->chr, avr_usart_can_receive,
+                             avr_usart_receive, NULL, NULL,
+                             s, NULL, true);
+    avr_usart_reset(dev);
+}
+
+static void avr_usart_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->reset = avr_usart_reset;
+    device_class_set_props(dc, avr_usart_properties);
+    dc->realize = avr_usart_realize;
+}
+
+static const TypeInfo avr_usart_info = {
+    .name          = TYPE_AVR_USART,
+    .parent        = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(AVRUsartState),
+    .instance_init = avr_usart_init,
+    .class_init    = avr_usart_class_init,
+};
+
+static void avr_usart_register_types(void)
+{
+    type_register_static(&avr_usart_info);
+}
+
+type_init(avr_usart_register_types)
diff --git a/hw/misc/Kconfig b/hw/misc/Kconfig
index bdd77d8020..92c397ca07 100644
--- a/hw/misc/Kconfig
+++ b/hw/misc/Kconfig
@@ -131,4 +131,7 @@ config MAC_VIA
     select MOS6522
     select ADB
 
+config AVR_POWER
+    bool
+
 source macio/Kconfig
diff --git a/hw/misc/Makefile.objs b/hw/misc/Makefile.objs
index 5aaca8a039..6be3d255ab 100644
--- a/hw/misc/Makefile.objs
+++ b/hw/misc/Makefile.objs
@@ -91,3 +91,5 @@ common-obj-$(CONFIG_NRF51_SOC) += nrf51_rng.o
 obj-$(CONFIG_MAC_VIA) += mac_via.o
 
 common-obj-$(CONFIG_GRLIB) += grlib_ahb_apb_pnp.o
+
+obj-$(CONFIG_AVR_POWER) += avr_power.o
diff --git a/hw/misc/avr_power.c b/hw/misc/avr_power.c
new file mode 100644
index 0000000000..a5412f2cfe
--- /dev/null
+++ b/hw/misc/avr_power.c
@@ -0,0 +1,113 @@
+/*
+ * AVR Power Reduction Management
+ *
+ * Copyright (c) 2019-2020 Michael Rolnik
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "qemu/osdep.h"
+#include "hw/misc/avr_power.h"
+#include "qemu/log.h"
+#include "hw/qdev-properties.h"
+#include "hw/irq.h"
+#include "trace.h"
+
+static void avr_mask_reset(DeviceState *dev)
+{
+    AVRMaskState *s = AVR_MASK(dev);
+
+    s->val = 0x00;
+
+    for (int i = 0; i < 8; i++) {
+        qemu_set_irq(s->irq[i], 0);
+    }
+}
+
+static uint64_t avr_mask_read(void *opaque, hwaddr offset, unsigned size)
+{
+    assert(size == 1);
+    assert(offset == 0);
+    AVRMaskState *s = opaque;
+
+    trace_avr_power_read(s->val);
+
+    return (uint64_t)s->val;
+}
+
+static void avr_mask_write(void *opaque, hwaddr offset,
+                           uint64_t val64, unsigned size)
+{
+    assert(size == 1);
+    assert(offset == 0);
+    AVRMaskState *s = opaque;
+    uint8_t val8 = val64;
+
+    trace_avr_power_write(val8);
+    s->val = val8;
+    for (int i = 0; i < 8; i++) {
+        qemu_set_irq(s->irq[i], (val8 & (1 << i)) != 0);
+    }
+}
+
+static const MemoryRegionOps avr_mask_ops = {
+    .read = avr_mask_read,
+    .write = avr_mask_write,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+    .impl = {
+        .max_access_size = 1,
+    },
+};
+
+static void avr_mask_init(Object *dev)
+{
+    AVRMaskState *s = AVR_MASK(dev);
+    SysBusDevice *busdev = SYS_BUS_DEVICE(dev);
+
+    memory_region_init_io(&s->iomem, dev, &avr_mask_ops, s, TYPE_AVR_MASK,
+                          0x01);
+    sysbus_init_mmio(busdev, &s->iomem);
+
+    for (int i = 0; i < 8; i++) {
+        sysbus_init_irq(busdev, &s->irq[i]);
+    }
+    s->val = 0x00;
+}
+
+static void avr_mask_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->reset = avr_mask_reset;
+}
+
+static const TypeInfo avr_mask_info = {
+    .name          = TYPE_AVR_MASK,
+    .parent        = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(AVRMaskState),
+    .class_init    = avr_mask_class_init,
+    .instance_init = avr_mask_init,
+};
+
+static void avr_mask_register_types(void)
+{
+    type_register_static(&avr_mask_info);
+}
+
+type_init(avr_mask_register_types)
diff --git a/hw/misc/trace-events b/hw/misc/trace-events
index ebea53735c..066752aa90 100644
--- a/hw/misc/trace-events
+++ b/hw/misc/trace-events
@@ -19,6 +19,10 @@ allwinner_h3_dramphy_write(uint64_t offset, uint64_t data, unsigned size) "write
 allwinner_sid_read(uint64_t offset, uint64_t data, unsigned size) "offset 0x%" PRIx64 " data 0x%" PRIx64 " size %" PRIu32
 allwinner_sid_write(uint64_t offset, uint64_t data, unsigned size) "offset 0x%" PRIx64 " data 0x%" PRIx64 " size %" PRIu32
 
+# avr_power.c
+avr_power_read(uint8_t value) "power_reduc read value:%u"
+avr_power_write(uint8_t value) "power_reduc write value:%u"
+
 # eccmemctl.c
 ecc_mem_writel_mer(uint32_t val) "Write memory enable 0x%08x"
 ecc_mem_writel_mdr(uint32_t val) "Write memory delay 0x%08x"
diff --git a/hw/timer/Kconfig b/hw/timer/Kconfig
index 59a667c503..8749edfb6a 100644
--- a/hw/timer/Kconfig
+++ b/hw/timer/Kconfig
@@ -41,3 +41,6 @@ config RENESAS_TMR
 
 config RENESAS_CMT
     bool
+
+config AVR_TIMER16
+    bool
diff --git a/hw/timer/Makefile.objs b/hw/timer/Makefile.objs
index a39f6ec0c2..1303b13e0d 100644
--- a/hw/timer/Makefile.objs
+++ b/hw/timer/Makefile.objs
@@ -37,3 +37,5 @@ common-obj-$(CONFIG_CMSDK_APB_TIMER) += cmsdk-apb-timer.o
 common-obj-$(CONFIG_CMSDK_APB_DUALTIMER) += cmsdk-apb-dualtimer.o
 common-obj-$(CONFIG_MSF2) += mss-timer.o
 common-obj-$(CONFIG_RASPI) += bcm2835_systmr.o
+
+obj-$(CONFIG_AVR_TIMER16) += avr_timer16.o
diff --git a/hw/timer/avr_timer16.c b/hw/timer/avr_timer16.c
new file mode 100644
index 0000000000..c48555da52
--- /dev/null
+++ b/hw/timer/avr_timer16.c
@@ -0,0 +1,621 @@
+/*
+ * AVR 16-bit timer
+ *
+ * Copyright (c) 2018 University of Kent
+ * Author: Ed Robbins
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see
+ * <http://www.gnu.org/licenses/lgpl-2.1.html>
+ */
+
+/*
+ * Driver for 16 bit timers on 8 bit AVR devices.
+ * Note:
+ * ATmega640/V-1280/V-1281/V-2560/V-2561/V timers 1, 3, 4 and 5 are 16 bit
+ */
+
+/*
+ * XXX TODO: Power Reduction Register support
+ *           prescaler pause support
+ *           PWM modes, GPIO, output capture pins, input compare pin
+ */
+
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "qemu/log.h"
+#include "hw/irq.h"
+#include "hw/qdev-properties.h"
+#include "hw/timer/avr_timer16.h"
+#include "trace.h"
+
+/* Register offsets */
+#define T16_CRA     0x0
+#define T16_CRB     0x1
+#define T16_CRC     0x2
+#define T16_CNTL    0x4
+#define T16_CNTH    0x5
+#define T16_ICRL    0x6
+#define T16_ICRH    0x7
+#define T16_OCRAL   0x8
+#define T16_OCRAH   0x9
+#define T16_OCRBL   0xa
+#define T16_OCRBH   0xb
+#define T16_OCRCL   0xc
+#define T16_OCRCH   0xd
+
+/* Field masks */
+#define T16_CRA_WGM01   0x3
+#define T16_CRA_COMC    0xc
+#define T16_CRA_COMB    0x30
+#define T16_CRA_COMA    0xc0
+#define T16_CRA_OC_CONF \
+    (T16_CRA_COMA | T16_CRA_COMB | T16_CRA_COMC)
+
+#define T16_CRB_CS      0x7
+#define T16_CRB_WGM23   0x18
+#define T16_CRB_ICES    0x40
+#define T16_CRB_ICNC    0x80
+
+#define T16_CRC_FOCC    0x20
+#define T16_CRC_FOCB    0x40
+#define T16_CRC_FOCA    0x80
+
+/* Fields masks both TIMSK and TIFR (interrupt mask/flag registers) */
+#define T16_INT_TOV    0x1 /* Timer overflow */
+#define T16_INT_OCA    0x2 /* Output compare A */
+#define T16_INT_OCB    0x4 /* Output compare B */
+#define T16_INT_OCC    0x8 /* Output compare C */
+#define T16_INT_IC     0x20 /* Input capture */
+
+/* Clock source values */
+#define T16_CLKSRC_STOPPED     0
+#define T16_CLKSRC_DIV1        1
+#define T16_CLKSRC_DIV8        2
+#define T16_CLKSRC_DIV64       3
+#define T16_CLKSRC_DIV256      4
+#define T16_CLKSRC_DIV1024     5
+#define T16_CLKSRC_EXT_FALLING 6
+#define T16_CLKSRC_EXT_RISING  7
+
+/* Timer mode values (not including PWM modes) */
+#define T16_MODE_NORMAL     0
+#define T16_MODE_CTC_OCRA   4
+#define T16_MODE_CTC_ICR    12
+
+/* Accessors */
+#define CLKSRC(t16) (t16->crb & T16_CRB_CS)
+#define MODE(t16)   (((t16->crb & T16_CRB_WGM23) >> 1) | \
+                     (t16->cra & T16_CRA_WGM01))
+#define CNT(t16)    VAL16(t16->cntl, t16->cnth)
+#define OCRA(t16)   VAL16(t16->ocral, t16->ocrah)
+#define OCRB(t16)   VAL16(t16->ocrbl, t16->ocrbh)
+#define OCRC(t16)   VAL16(t16->ocrcl, t16->ocrch)
+#define ICR(t16)    VAL16(t16->icrl, t16->icrh)
+
+/* Helper macros */
+#define VAL16(l, h) ((h << 8) | l)
+#define DB_PRINT(fmt, args...) /* Nothing */
+
+static inline int64_t avr_timer16_ns_to_ticks(AVRTimer16State *t16, int64_t t)
+{
+    if (t16->period_ns == 0) {
+        return 0;
+    }
+    return t / t16->period_ns;
+}
+
+static void avr_timer16_update_cnt(AVRTimer16State *t16)
+{
+    uint16_t cnt;
+    cnt = avr_timer16_ns_to_ticks(t16, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) -
+                                       t16->reset_time_ns);
+    t16->cntl = (uint8_t)(cnt & 0xff);
+    t16->cnth = (uint8_t)((cnt & 0xff00) >> 8);
+}
+
+static inline void avr_timer16_recalc_reset_time(AVRTimer16State *t16)
+{
+    t16->reset_time_ns = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) -
+                         CNT(t16) * t16->period_ns;
+}
+
+static void avr_timer16_clock_reset(AVRTimer16State *t16)
+{
+    t16->cntl = 0;
+    t16->cnth = 0;
+    t16->reset_time_ns = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+}
+
+static void avr_timer16_clksrc_update(AVRTimer16State *t16)
+{
+    uint16_t divider = 0;
+    switch (CLKSRC(t16)) {
+    case T16_CLKSRC_EXT_FALLING:
+    case T16_CLKSRC_EXT_RISING:
+        qemu_log_mask(LOG_UNIMP, "%s: external clock source unsupported\n",
+                      __func__);
+        break;
+    case T16_CLKSRC_STOPPED:
+        break;
+    case T16_CLKSRC_DIV1:
+        divider = 1;
+        break;
+    case T16_CLKSRC_DIV8:
+        divider = 8;
+        break;
+    case T16_CLKSRC_DIV64:
+        divider = 64;
+        break;
+    case T16_CLKSRC_DIV256:
+        divider = 256;
+        break;
+    case T16_CLKSRC_DIV1024:
+        divider = 1024;
+        break;
+    default:
+        break;
+    }
+    if (divider) {
+        t16->freq_hz = t16->cpu_freq_hz / divider;
+        t16->period_ns = NANOSECONDS_PER_SECOND / t16->freq_hz;
+        trace_avr_timer16_clksrc_update(t16->freq_hz, t16->period_ns,
+                                        (uint64_t)(1e6 / t16->freq_hz));
+    }
+}
+
+static void avr_timer16_set_alarm(AVRTimer16State *t16)
+{
+    if (CLKSRC(t16) == T16_CLKSRC_EXT_FALLING ||
+        CLKSRC(t16) == T16_CLKSRC_EXT_RISING ||
+        CLKSRC(t16) == T16_CLKSRC_STOPPED) {
+        /* Timer is disabled or set to external clock source (unsupported) */
+        return;
+    }
+
+    uint64_t alarm_offset = 0xffff;
+    enum NextInterrupt next_interrupt = OVERFLOW;
+
+    switch (MODE(t16)) {
+    case T16_MODE_NORMAL:
+        /* Normal mode */
+        if (OCRA(t16) < alarm_offset && OCRA(t16) > CNT(t16) &&
+            (t16->imsk & T16_INT_OCA)) {
+            alarm_offset = OCRA(t16);
+            next_interrupt = COMPA;
+        }
+        break;
+    case T16_MODE_CTC_OCRA:
+        /* CTC mode, top = ocra */
+        if (OCRA(t16) < alarm_offset && OCRA(t16) > CNT(t16)) {
+            alarm_offset = OCRA(t16);
+            next_interrupt = COMPA;
+        }
+       break;
+    case T16_MODE_CTC_ICR:
+        /* CTC mode, top = icr */
+        if (ICR(t16) < alarm_offset && ICR(t16) > CNT(t16)) {
+            alarm_offset = ICR(t16);
+            next_interrupt = CAPT;
+        }
+        if (OCRA(t16) < alarm_offset && OCRA(t16) > CNT(t16) &&
+            (t16->imsk & T16_INT_OCA)) {
+            alarm_offset = OCRA(t16);
+            next_interrupt = COMPA;
+        }
+        break;
+    default:
+        qemu_log_mask(LOG_UNIMP, "%s: pwm modes are unsupported\n",
+                      __func__);
+        return;
+    }
+    if (OCRB(t16) < alarm_offset && OCRB(t16) > CNT(t16) &&
+        (t16->imsk & T16_INT_OCB)) {
+        alarm_offset = OCRB(t16);
+        next_interrupt = COMPB;
+    }
+    if (OCRC(t16) < alarm_offset && OCRB(t16) > CNT(t16) &&
+        (t16->imsk & T16_INT_OCC)) {
+        alarm_offset = OCRB(t16);
+        next_interrupt = COMPC;
+    }
+    alarm_offset -= CNT(t16);
+
+    t16->next_interrupt = next_interrupt;
+    uint64_t alarm_ns =
+        t16->reset_time_ns + ((CNT(t16) + alarm_offset) * t16->period_ns);
+    timer_mod(t16->timer, alarm_ns);
+
+    trace_avr_timer16_next_alarm(alarm_offset * t16->period_ns);
+}
+
+static void avr_timer16_interrupt(void *opaque)
+{
+    AVRTimer16State *t16 = opaque;
+    uint8_t mode = MODE(t16);
+
+    avr_timer16_update_cnt(t16);
+
+    if (CLKSRC(t16) == T16_CLKSRC_EXT_FALLING ||
+        CLKSRC(t16) == T16_CLKSRC_EXT_RISING ||
+        CLKSRC(t16) == T16_CLKSRC_STOPPED) {
+        /* Timer is disabled or set to external clock source (unsupported) */
+        return;
+    }
+
+    trace_avr_timer16_interrupt_count(CNT(t16));
+
+    /* Counter overflow */
+    if (t16->next_interrupt == OVERFLOW) {
+        trace_avr_timer16_interrupt_overflow("counter 0xffff");
+        avr_timer16_clock_reset(t16);
+        if (t16->imsk & T16_INT_TOV) {
+            t16->ifr |= T16_INT_TOV;
+            qemu_set_irq(t16->ovf_irq, 1);
+        }
+    }
+    /* Check for ocra overflow in CTC mode */
+    if (mode == T16_MODE_CTC_OCRA && t16->next_interrupt == COMPA) {
+        trace_avr_timer16_interrupt_overflow("CTC OCRA");
+        avr_timer16_clock_reset(t16);
+    }
+    /* Check for icr overflow in CTC mode */
+    if (mode == T16_MODE_CTC_ICR && t16->next_interrupt == CAPT) {
+        trace_avr_timer16_interrupt_overflow("CTC ICR");
+        avr_timer16_clock_reset(t16);
+        if (t16->imsk & T16_INT_IC) {
+            t16->ifr |= T16_INT_IC;
+            qemu_set_irq(t16->capt_irq, 1);
+        }
+    }
+    /* Check for output compare interrupts */
+    if (t16->imsk & T16_INT_OCA && t16->next_interrupt == COMPA) {
+        t16->ifr |= T16_INT_OCA;
+        qemu_set_irq(t16->compa_irq, 1);
+    }
+    if (t16->imsk & T16_INT_OCB && t16->next_interrupt == COMPB) {
+        t16->ifr |= T16_INT_OCB;
+        qemu_set_irq(t16->compb_irq, 1);
+    }
+    if (t16->imsk & T16_INT_OCC && t16->next_interrupt == COMPC) {
+        t16->ifr |= T16_INT_OCC;
+        qemu_set_irq(t16->compc_irq, 1);
+    }
+    avr_timer16_set_alarm(t16);
+}
+
+static void avr_timer16_reset(DeviceState *dev)
+{
+    AVRTimer16State *t16 = AVR_TIMER16(dev);
+
+    avr_timer16_clock_reset(t16);
+    avr_timer16_clksrc_update(t16);
+    avr_timer16_set_alarm(t16);
+
+    qemu_set_irq(t16->capt_irq, 0);
+    qemu_set_irq(t16->compa_irq, 0);
+    qemu_set_irq(t16->compb_irq, 0);
+    qemu_set_irq(t16->compc_irq, 0);
+    qemu_set_irq(t16->ovf_irq, 0);
+}
+
+static uint64_t avr_timer16_read(void *opaque, hwaddr offset, unsigned size)
+{
+    assert(size == 1);
+    AVRTimer16State *t16 = opaque;
+    uint8_t retval = 0;
+
+    switch (offset) {
+    case T16_CRA:
+        retval = t16->cra;
+        break;
+    case T16_CRB:
+        retval = t16->crb;
+        break;
+    case T16_CRC:
+        retval = t16->crc;
+        break;
+    case T16_CNTL:
+        avr_timer16_update_cnt(t16);
+        t16->rtmp = t16->cnth;
+        retval = t16->cntl;
+        break;
+    case T16_CNTH:
+        retval = t16->rtmp;
+        break;
+    case T16_ICRL:
+        /*
+         * The timer copies cnt to icr when the input capture pin changes
+         * state or when the analog comparator has a match. We don't
+         * emulate this behaviour. We do support it's use for defining a
+         * TOP value in T16_MODE_CTC_ICR
+         */
+        t16->rtmp = t16->icrh;
+        retval = t16->icrl;
+        break;
+    case T16_ICRH:
+        retval = t16->rtmp;
+        break;
+    case T16_OCRAL:
+        retval = t16->ocral;
+        break;
+    case T16_OCRAH:
+        retval = t16->ocrah;
+        break;
+    case T16_OCRBL:
+        retval = t16->ocrbl;
+        break;
+    case T16_OCRBH:
+        retval = t16->ocrbh;
+        break;
+    case T16_OCRCL:
+        retval = t16->ocrcl;
+        break;
+    case T16_OCRCH:
+        retval = t16->ocrch;
+        break;
+    default:
+        break;
+    }
+    trace_avr_timer16_read(offset, retval);
+
+    return (uint64_t)retval;
+}
+
+static void avr_timer16_write(void *opaque, hwaddr offset,
+                              uint64_t val64, unsigned size)
+{
+    assert(size == 1);
+    AVRTimer16State *t16 = opaque;
+    uint8_t val8 = (uint8_t)val64;
+    uint8_t prev_clk_src = CLKSRC(t16);
+
+    trace_avr_timer16_write(offset, val8);
+
+    switch (offset) {
+    case T16_CRA:
+        t16->cra = val8;
+        if (t16->cra & T16_CRA_OC_CONF) {
+            qemu_log_mask(LOG_UNIMP, "%s: output compare pins unsupported\n",
+                          __func__);
+        }
+        break;
+    case T16_CRB:
+        t16->crb = val8;
+        if (t16->crb & T16_CRB_ICNC) {
+            qemu_log_mask(LOG_UNIMP,
+                          "%s: input capture noise canceller unsupported\n",
+                          __func__);
+        }
+        if (t16->crb & T16_CRB_ICES) {
+            qemu_log_mask(LOG_UNIMP, "%s: input capture unsupported\n",
+                          __func__);
+        }
+        if (CLKSRC(t16) != prev_clk_src) {
+            avr_timer16_clksrc_update(t16);
+            if (prev_clk_src == T16_CLKSRC_STOPPED) {
+                t16->reset_time_ns = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+            }
+        }
+        break;
+    case T16_CRC:
+        t16->crc = val8;
+        qemu_log_mask(LOG_UNIMP, "%s: output compare pins unsupported\n",
+                      __func__);
+        break;
+    case T16_CNTL:
+        /*
+         * CNT is the 16-bit counter value, it must be read/written via
+         * a temporary register (rtmp) to make the read/write atomic.
+         */
+        /* ICR also has this behaviour, and shares rtmp */
+        /*
+         * Writing CNT blocks compare matches for one clock cycle.
+         * Writing CNT to TOP or to an OCR value (if in use) will
+         * skip the relevant interrupt
+         */
+        t16->cntl = val8;
+        t16->cnth = t16->rtmp;
+        avr_timer16_recalc_reset_time(t16);
+        break;
+    case T16_CNTH:
+        t16->rtmp = val8;
+        break;
+    case T16_ICRL:
+        /* ICR can only be written in mode T16_MODE_CTC_ICR */
+        if (MODE(t16) == T16_MODE_CTC_ICR) {
+            t16->icrl = val8;
+            t16->icrh = t16->rtmp;
+        }
+        break;
+    case T16_ICRH:
+        if (MODE(t16) == T16_MODE_CTC_ICR) {
+            t16->rtmp = val8;
+        }
+        break;
+    case T16_OCRAL:
+        /*
+         * OCRn cause the relevant output compare flag to be raised, and
+         * trigger an interrupt, when CNT is equal to the value here
+         */
+        t16->ocral = val8;
+        break;
+    case T16_OCRAH:
+        t16->ocrah = val8;
+        break;
+    case T16_OCRBL:
+        t16->ocrbl = val8;
+        break;
+    case T16_OCRBH:
+        t16->ocrbh = val8;
+        break;
+    case T16_OCRCL:
+        t16->ocrcl = val8;
+        break;
+    case T16_OCRCH:
+        t16->ocrch = val8;
+        break;
+    default:
+        break;
+    }
+    avr_timer16_set_alarm(t16);
+}
+
+static uint64_t avr_timer16_imsk_read(void *opaque,
+                                      hwaddr offset,
+                                      unsigned size)
+{
+    assert(size == 1);
+    AVRTimer16State *t16 = opaque;
+    trace_avr_timer16_read_imsk(offset ? 0 : t16->imsk);
+    if (offset != 0) {
+        return 0;
+    }
+    return t16->imsk;
+}
+
+static void avr_timer16_imsk_write(void *opaque, hwaddr offset,
+                                   uint64_t val64, unsigned size)
+{
+    assert(size == 1);
+    AVRTimer16State *t16 = opaque;
+    trace_avr_timer16_write_imsk(val64);
+    if (offset != 0) {
+        return;
+    }
+    t16->imsk = (uint8_t)val64;
+}
+
+static uint64_t avr_timer16_ifr_read(void *opaque,
+                                     hwaddr offset,
+                                     unsigned size)
+{
+    assert(size == 1);
+    AVRTimer16State *t16 = opaque;
+    trace_avr_timer16_read_ifr(offset ? 0 : t16->ifr);
+    if (offset != 0) {
+        return 0;
+    }
+    return t16->ifr;
+}
+
+static void avr_timer16_ifr_write(void *opaque, hwaddr offset,
+                                  uint64_t val64, unsigned size)
+{
+    assert(size == 1);
+    AVRTimer16State *t16 = opaque;
+    trace_avr_timer16_write_imsk(val64);
+    if (offset != 0) {
+        return;
+    }
+    t16->ifr = (uint8_t)val64;
+}
+
+static const MemoryRegionOps avr_timer16_ops = {
+    .read = avr_timer16_read,
+    .write = avr_timer16_write,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+    .impl = {.max_access_size = 1}
+};
+
+static const MemoryRegionOps avr_timer16_imsk_ops = {
+    .read = avr_timer16_imsk_read,
+    .write = avr_timer16_imsk_write,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+    .impl = {.max_access_size = 1}
+};
+
+static const MemoryRegionOps avr_timer16_ifr_ops = {
+    .read = avr_timer16_ifr_read,
+    .write = avr_timer16_ifr_write,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+    .impl = {.max_access_size = 1}
+};
+
+static Property avr_timer16_properties[] = {
+    DEFINE_PROP_UINT8("id", struct AVRTimer16State, id, 0),
+    DEFINE_PROP_UINT64("cpu-frequency-hz", struct AVRTimer16State,
+                       cpu_freq_hz, 0),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static void avr_timer16_pr(void *opaque, int irq, int level)
+{
+    AVRTimer16State *s = AVR_TIMER16(opaque);
+
+    s->enabled = !level;
+
+    if (!s->enabled) {
+        avr_timer16_reset(DEVICE(s));
+    }
+}
+
+static void avr_timer16_init(Object *obj)
+{
+    AVRTimer16State *s = AVR_TIMER16(obj);
+
+    sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->capt_irq);
+    sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->compa_irq);
+    sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->compb_irq);
+    sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->compc_irq);
+    sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->ovf_irq);
+
+    memory_region_init_io(&s->iomem, obj, &avr_timer16_ops,
+                          s, "avr-timer16", 0xe);
+    memory_region_init_io(&s->imsk_iomem, obj, &avr_timer16_imsk_ops,
+                          s, "avr-timer16-intmask", 0x1);
+    memory_region_init_io(&s->ifr_iomem, obj, &avr_timer16_ifr_ops,
+                          s, "avr-timer16-intflag", 0x1);
+
+    sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->iomem);
+    sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->imsk_iomem);
+    sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->ifr_iomem);
+    qdev_init_gpio_in(DEVICE(s), avr_timer16_pr, 1);
+}
+
+static void avr_timer16_realize(DeviceState *dev, Error **errp)
+{
+    AVRTimer16State *s = AVR_TIMER16(dev);
+
+    if (s->cpu_freq_hz == 0) {
+        error_setg(errp, "AVR timer16: cpu-frequency-hz property must be set");
+        return;
+    }
+
+    s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, avr_timer16_interrupt, s);
+    s->enabled = true;
+}
+
+static void avr_timer16_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->reset = avr_timer16_reset;
+    dc->realize = avr_timer16_realize;
+    device_class_set_props(dc, avr_timer16_properties);
+}
+
+static const TypeInfo avr_timer16_info = {
+    .name          = TYPE_AVR_TIMER16,
+    .parent        = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(AVRTimer16State),
+    .instance_init = avr_timer16_init,
+    .class_init    = avr_timer16_class_init,
+};
+
+static void avr_timer16_register_types(void)
+{
+    type_register_static(&avr_timer16_info);
+}
+
+type_init(avr_timer16_register_types)
diff --git a/hw/timer/trace-events b/hw/timer/trace-events
index 866c9f546a..447b7c405b 100644
--- a/hw/timer/trace-events
+++ b/hw/timer/trace-events
@@ -75,3 +75,15 @@ nrf51_timer_set_count(uint8_t timer_id, uint8_t counter_id, uint32_t value) "tim
 bcm2835_systmr_irq(bool enable) "timer irq state %u"
 bcm2835_systmr_read(uint64_t offset, uint64_t data) "timer read: offset 0x%" PRIx64 " data 0x%" PRIx64
 bcm2835_systmr_write(uint64_t offset, uint64_t data) "timer write: offset 0x%" PRIx64 " data 0x%" PRIx64
+
+# avr_timer16.c
+avr_timer16_read(uint8_t addr, uint8_t value) "timer16 read addr:%u value:%u"
+avr_timer16_read_ifr(uint8_t value) "timer16 read addr:ifr value:%u"
+avr_timer16_read_imsk(uint8_t value) "timer16 read addr:imsk value:%u"
+avr_timer16_write(uint8_t addr, uint8_t value) "timer16 write addr:%u value:%u"
+avr_timer16_write_ifr(uint8_t value) "timer16 write addr:ifr value:%u"
+avr_timer16_write_imsk(uint8_t value) "timer16 write addr:imsk value:%u"
+avr_timer16_interrupt_count(uint8_t cnt) "count: %u"
+avr_timer16_interrupt_overflow(const char *reason) "overflow: %s"
+avr_timer16_next_alarm(uint64_t delay_ns) "next alarm: %" PRIu64 " ns from now"
+avr_timer16_clksrc_update(uint64_t freq_hz, uint64_t period_ns, uint64_t delay_s) "timer frequency: %" PRIu64 " Hz, period: %" PRIu64 " ns (%" PRId64 " us)"
diff --git a/include/disas/dis-asm.h b/include/disas/dis-asm.h
index c5f9fa08ab..9856bf7921 100644
--- a/include/disas/dis-asm.h
+++ b/include/disas/dis-asm.h
@@ -211,6 +211,25 @@ enum bfd_architecture
 #define bfd_mach_m32r          0  /* backwards compatibility */
   bfd_arch_mn10200,    /* Matsushita MN10200 */
   bfd_arch_mn10300,    /* Matsushita MN10300 */
+  bfd_arch_avr,        /* AVR microcontrollers */
+#define bfd_mach_avr1       1
+#define bfd_mach_avr2       2
+#define bfd_mach_avr25      25
+#define bfd_mach_avr3       3
+#define bfd_mach_avr31      31
+#define bfd_mach_avr35      35
+#define bfd_mach_avr4       4
+#define bfd_mach_avr5       5
+#define bfd_mach_avr51      51
+#define bfd_mach_avr6       6
+#define bfd_mach_avrtiny    100
+#define bfd_mach_avrxmega1  101
+#define bfd_mach_avrxmega2  102
+#define bfd_mach_avrxmega3  103
+#define bfd_mach_avrxmega4  104
+#define bfd_mach_avrxmega5  105
+#define bfd_mach_avrxmega6  106
+#define bfd_mach_avrxmega7  107
   bfd_arch_cris,       /* Axis CRIS */
 #define bfd_mach_cris_v0_v10   255
 #define bfd_mach_cris_v32      32
diff --git a/include/elf.h b/include/elf.h
index 8fbfe60e09..5b06b55f28 100644
--- a/include/elf.h
+++ b/include/elf.h
@@ -160,6 +160,8 @@ typedef struct mips_elf_abiflags_v0 {
 
 #define EM_CRIS         76      /* Axis Communications 32-bit embedded processor */
 
+#define EM_AVR          83      /* AVR 8-bit microcontroller */
+
 #define EM_V850		87	/* NEC v850 */
 
 #define EM_H8_300H      47      /* Hitachi H8/300H */
@@ -202,6 +204,8 @@ typedef struct mips_elf_abiflags_v0 {
 #define EM_MOXIE           223     /* Moxie processor family */
 #define EM_MOXIE_OLD       0xFEED
 
+#define EF_AVR_MACH     0x7F       /* Mask for AVR e_flags to get core type */
+
 /* This is the info that is needed to parse the dynamic section of the file */
 #define DT_NULL		0
 #define DT_NEEDED	1
diff --git a/include/hw/char/avr_usart.h b/include/hw/char/avr_usart.h
new file mode 100644
index 0000000000..5739aaf26f
--- /dev/null
+++ b/include/hw/char/avr_usart.h
@@ -0,0 +1,93 @@
+/*
+ * AVR USART
+ *
+ * Copyright (c) 2018 University of Kent
+ * Author: Sarah Harris
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see
+ * <http://www.gnu.org/licenses/lgpl-2.1.html>
+ */
+
+#ifndef HW_CHAR_AVR_USART_H
+#define HW_CHAR_AVR_USART_H
+
+#include "hw/sysbus.h"
+#include "chardev/char-fe.h"
+#include "hw/hw.h"
+
+/* Offsets of registers. */
+#define USART_DR   0x06
+#define USART_CSRA  0x00
+#define USART_CSRB  0x01
+#define USART_CSRC  0x02
+#define USART_BRRH 0x05
+#define USART_BRRL 0x04
+
+/* Relevant bits in regiters. */
+#define USART_CSRA_RXC    (1 << 7)
+#define USART_CSRA_TXC    (1 << 6)
+#define USART_CSRA_DRE    (1 << 5)
+#define USART_CSRA_MPCM   (1 << 0)
+
+#define USART_CSRB_RXCIE  (1 << 7)
+#define USART_CSRB_TXCIE  (1 << 6)
+#define USART_CSRB_DREIE  (1 << 5)
+#define USART_CSRB_RXEN   (1 << 4)
+#define USART_CSRB_TXEN   (1 << 3)
+#define USART_CSRB_CSZ2   (1 << 2)
+#define USART_CSRB_RXB8   (1 << 1)
+#define USART_CSRB_TXB8   (1 << 0)
+
+#define USART_CSRC_MSEL1  (1 << 7)
+#define USART_CSRC_MSEL0  (1 << 6)
+#define USART_CSRC_PM1    (1 << 5)
+#define USART_CSRC_PM0    (1 << 4)
+#define USART_CSRC_CSZ1   (1 << 2)
+#define USART_CSRC_CSZ0   (1 << 1)
+
+#define TYPE_AVR_USART "avr-usart"
+#define AVR_USART(obj) \
+    OBJECT_CHECK(AVRUsartState, (obj), TYPE_AVR_USART)
+
+typedef struct {
+    /* <private> */
+    SysBusDevice parent_obj;
+
+    /* <public> */
+    MemoryRegion mmio;
+
+    CharBackend chr;
+
+    bool enabled;
+
+    uint8_t data;
+    bool data_valid;
+    uint8_t char_mask;
+    /* Control and Status Registers */
+    uint8_t csra;
+    uint8_t csrb;
+    uint8_t csrc;
+    /* Baud Rate Registers (low/high byte) */
+    uint8_t brrh;
+    uint8_t brrl;
+
+    /* Receive Complete */
+    qemu_irq rxc_irq;
+    /* Transmit Complete */
+    qemu_irq txc_irq;
+    /* Data Register Empty */
+    qemu_irq dre_irq;
+} AVRUsartState;
+
+#endif /* HW_CHAR_AVR_USART_H */
diff --git a/include/hw/misc/avr_power.h b/include/hw/misc/avr_power.h
new file mode 100644
index 0000000000..e08e44f629
--- /dev/null
+++ b/include/hw/misc/avr_power.h
@@ -0,0 +1,46 @@
+/*
+ * AVR Power Reduction Management
+ *
+ * Copyright (c) 2019-2020 Michael Rolnik
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef HW_MISC_AVR_POWER_H
+#define HW_MISC_AVR_POWER_H
+
+#include "hw/sysbus.h"
+#include "hw/hw.h"
+
+
+#define TYPE_AVR_MASK "avr-power"
+#define AVR_MASK(obj) OBJECT_CHECK(AVRMaskState, (obj), TYPE_AVR_MASK)
+
+typedef struct {
+    /* <private> */
+    SysBusDevice parent_obj;
+
+    /* <public> */
+    MemoryRegion iomem;
+
+    uint8_t val;
+    qemu_irq irq[8];
+} AVRMaskState;
+
+#endif /* HW_MISC_AVR_POWER_H */
diff --git a/include/hw/timer/avr_timer16.h b/include/hw/timer/avr_timer16.h
new file mode 100644
index 0000000000..982019d242
--- /dev/null
+++ b/include/hw/timer/avr_timer16.h
@@ -0,0 +1,94 @@
+/*
+ * AVR 16-bit timer
+ *
+ * Copyright (c) 2018 University of Kent
+ * Author: Ed Robbins
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see
+ * <http://www.gnu.org/licenses/lgpl-2.1.html>
+ */
+
+/*
+ * Driver for 16 bit timers on 8 bit AVR devices.
+ * Note:
+ * On ATmega640/V-1280/V-1281/V-2560/V-2561/V timers 1, 3, 4 and 5 are 16 bit
+ */
+
+#ifndef HW_TIMER_AVR_TIMER16_H
+#define HW_TIMER_AVR_TIMER16_H
+
+#include "hw/sysbus.h"
+#include "qemu/timer.h"
+#include "hw/hw.h"
+
+enum NextInterrupt {
+    OVERFLOW,
+    COMPA,
+    COMPB,
+    COMPC,
+    CAPT
+};
+
+#define TYPE_AVR_TIMER16 "avr-timer16"
+#define AVR_TIMER16(obj) \
+    OBJECT_CHECK(AVRTimer16State, (obj), TYPE_AVR_TIMER16)
+
+typedef struct AVRTimer16State {
+    /* <private> */
+    SysBusDevice parent_obj;
+
+    /* <public> */
+    MemoryRegion iomem;
+    MemoryRegion imsk_iomem;
+    MemoryRegion ifr_iomem;
+    QEMUTimer *timer;
+    qemu_irq capt_irq;
+    qemu_irq compa_irq;
+    qemu_irq compb_irq;
+    qemu_irq compc_irq;
+    qemu_irq ovf_irq;
+
+    bool enabled;
+
+    /* registers */
+    uint8_t cra;
+    uint8_t crb;
+    uint8_t crc;
+    uint8_t cntl;
+    uint8_t cnth;
+    uint8_t icrl;
+    uint8_t icrh;
+    uint8_t ocral;
+    uint8_t ocrah;
+    uint8_t ocrbl;
+    uint8_t ocrbh;
+    uint8_t ocrcl;
+    uint8_t ocrch;
+    /*
+     * Reads and writes to CNT and ICR utilise a bizarre temporary
+     * register, which we emulate
+     */
+    uint8_t rtmp;
+    uint8_t imsk;
+    uint8_t ifr;
+
+    uint8_t id;
+    uint64_t cpu_freq_hz;
+    uint64_t freq_hz;
+    uint64_t period_ns;
+    uint64_t reset_time_ns;
+    enum NextInterrupt next_interrupt;
+} AVRTimer16State;
+
+#endif /* HW_TIMER_AVR_TIMER16_H */
diff --git a/include/sysemu/arch_init.h b/include/sysemu/arch_init.h
index 71a7a285ee..54f069d491 100644
--- a/include/sysemu/arch_init.h
+++ b/include/sysemu/arch_init.h
@@ -25,6 +25,7 @@ enum {
     QEMU_ARCH_HPPA = (1 << 18),
     QEMU_ARCH_RISCV = (1 << 19),
     QEMU_ARCH_RX = (1 << 20),
+    QEMU_ARCH_AVR = (1 << 21),
 
     QEMU_ARCH_NONE = (1 << 31),
 };
diff --git a/qapi/machine.json b/qapi/machine.json
index ff7b5032e3..f59144023c 100644
--- a/qapi/machine.json
+++ b/qapi/machine.json
@@ -17,6 +17,7 @@
 # being.
 #
 # @rx: since 5.0
+# @avr: since 5.1
 #
 # Notes: The resulting QMP strings can be appended to the "qemu-system-"
 #        prefix to produce the corresponding QEMU executable name. This
@@ -25,7 +26,7 @@
 # Since: 3.0
 ##
 { 'enum' : 'SysEmuTarget',
-  'data' : [ 'aarch64', 'alpha', 'arm', 'cris', 'hppa', 'i386', 'lm32',
+  'data' : [ 'aarch64', 'alpha', 'arm', 'avr', 'cris', 'hppa', 'i386', 'lm32',
              'm68k', 'microblaze', 'microblazeel', 'mips', 'mips64',
              'mips64el', 'mipsel', 'moxie', 'nios2', 'or1k', 'ppc',
              'ppc64', 'riscv32', 'riscv64', 'rx', 's390x', 'sh4',
diff --git a/softmmu/arch_init.c b/softmmu/arch_init.c
index 8afea4748b..7fd5c09b2b 100644
--- a/softmmu/arch_init.c
+++ b/softmmu/arch_init.c
@@ -90,6 +90,8 @@ int graphic_depth = 32;
 #define QEMU_ARCH QEMU_ARCH_UNICORE32
 #elif defined(TARGET_XTENSA)
 #define QEMU_ARCH QEMU_ARCH_XTENSA
+#elif defined(TARGET_AVR)
+#define QEMU_ARCH QEMU_ARCH_AVR
 #endif
 
 const uint32_t arch_type = QEMU_ARCH;
diff --git a/target/avr/Makefile.objs b/target/avr/Makefile.objs
new file mode 100644
index 0000000000..6e35ba2c5c
--- /dev/null
+++ b/target/avr/Makefile.objs
@@ -0,0 +1,34 @@
+#
+#  QEMU AVR
+#
+#  Copyright (c) 2016-2020 Michael Rolnik
+#
+#  This library is free software; you can redistribute it and/or
+#  modify it under the terms of the GNU Lesser General Public
+#  License as published by the Free Software Foundation; either
+#  version 2.1 of the License, or (at your option) any later version.
+#
+#  This library is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+#  Lesser General Public License for more details.
+#
+#  You should have received a copy of the GNU Lesser General Public
+#  License along with this library; if not, see
+#  <http://www.gnu.org/licenses/lgpl-2.1.html>
+#
+
+DECODETREE = $(SRC_PATH)/scripts/decodetree.py
+decode-y = $(SRC_PATH)/target/avr/insn.decode
+
+target/avr/decode_insn.inc.c: $(decode-y) $(DECODETREE)
+	$(call quiet-command, \
+	  $(PYTHON) $(DECODETREE) -o $@ --decode decode_insn --insnwidth 16 $<, \
+	  "GEN", $(TARGET_DIR)$@)
+
+target/avr/translate.o: target/avr/decode_insn.inc.c
+
+obj-y += translate.o cpu.o helper.o
+obj-y += gdbstub.o
+obj-y += disas.o
+obj-$(CONFIG_SOFTMMU) += machine.o
diff --git a/target/avr/cpu-param.h b/target/avr/cpu-param.h
new file mode 100644
index 0000000000..7ef4e7c679
--- /dev/null
+++ b/target/avr/cpu-param.h
@@ -0,0 +1,36 @@
+/*
+ * QEMU AVR CPU
+ *
+ * Copyright (c) 2016-2020 Michael Rolnik
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see
+ * <http://www.gnu.org/licenses/lgpl-2.1.html>
+ */
+
+#ifndef AVR_CPU_PARAM_H
+#define AVR_CPU_PARAM_H
+
+#define TARGET_LONG_BITS 32
+/*
+ * TARGET_PAGE_BITS cannot be more than 8 bits because
+ * 1.  all IO registers occupy [0x0000 .. 0x00ff] address range, and they
+ *     should be implemented as a device and not memory
+ * 2.  SRAM starts at the address 0x0100
+ */
+#define TARGET_PAGE_BITS 8
+#define TARGET_PHYS_ADDR_SPACE_BITS 24
+#define TARGET_VIRT_ADDR_SPACE_BITS 24
+#define NB_MMU_MODES 2
+
+#endif
diff --git a/target/avr/cpu-qom.h b/target/avr/cpu-qom.h
new file mode 100644
index 0000000000..d23ad43a99
--- /dev/null
+++ b/target/avr/cpu-qom.h
@@ -0,0 +1,53 @@
+/*
+ * QEMU AVR CPU
+ *
+ * Copyright (c) 2016-2020 Michael Rolnik
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see
+ * <http://www.gnu.org/licenses/lgpl-2.1.html>
+ */
+
+#ifndef QEMU_AVR_QOM_H
+#define QEMU_AVR_QOM_H
+
+#include "hw/core/cpu.h"
+
+#define TYPE_AVR_CPU "avr-cpu"
+
+#define AVR_CPU_CLASS(klass) \
+    OBJECT_CLASS_CHECK(AVRCPUClass, (klass), TYPE_AVR_CPU)
+#define AVR_CPU(obj) \
+    OBJECT_CHECK(AVRCPU, (obj), TYPE_AVR_CPU)
+#define AVR_CPU_GET_CLASS(obj) \
+    OBJECT_GET_CLASS(AVRCPUClass, (obj), TYPE_AVR_CPU)
+
+/**
+ *  AVRCPUClass:
+ *  @parent_realize: The parent class' realize handler.
+ *  @parent_reset: The parent class' reset handler.
+ *  @vr: Version Register value.
+ *
+ *  A AVR CPU model.
+ */
+typedef struct AVRCPUClass {
+    /*< private >*/
+    CPUClass parent_class;
+    /*< public >*/
+    DeviceRealize parent_realize;
+    DeviceReset parent_reset;
+} AVRCPUClass;
+
+typedef struct AVRCPU AVRCPU;
+
+#endif /* !defined (QEMU_AVR_CPU_QOM_H) */
diff --git a/target/avr/cpu.c b/target/avr/cpu.c
new file mode 100644
index 0000000000..5d9c4ad5bf
--- /dev/null
+++ b/target/avr/cpu.c
@@ -0,0 +1,366 @@
+/*
+ * QEMU AVR CPU
+ *
+ * Copyright (c) 2019-2020 Michael Rolnik
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see
+ * <http://www.gnu.org/licenses/lgpl-2.1.html>
+ */
+
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "qemu/qemu-print.h"
+#include "exec/exec-all.h"
+#include "cpu.h"
+#include "disas/dis-asm.h"
+
+static void avr_cpu_set_pc(CPUState *cs, vaddr value)
+{
+    AVRCPU *cpu = AVR_CPU(cs);
+
+    cpu->env.pc_w = value / 2; /* internally PC points to words */
+}
+
+static bool avr_cpu_has_work(CPUState *cs)
+{
+    AVRCPU *cpu = AVR_CPU(cs);
+    CPUAVRState *env = &cpu->env;
+
+    return (cs->interrupt_request & (CPU_INTERRUPT_HARD | CPU_INTERRUPT_RESET))
+            && cpu_interrupts_enabled(env);
+}
+
+static void avr_cpu_synchronize_from_tb(CPUState *cs, TranslationBlock *tb)
+{
+    AVRCPU *cpu = AVR_CPU(cs);
+    CPUAVRState *env = &cpu->env;
+
+    env->pc_w = tb->pc / 2; /* internally PC points to words */
+}
+
+static void avr_cpu_reset(DeviceState *ds)
+{
+    CPUState *cs = CPU(ds);
+    AVRCPU *cpu = AVR_CPU(cs);
+    AVRCPUClass *mcc = AVR_CPU_GET_CLASS(cpu);
+    CPUAVRState *env = &cpu->env;
+
+    mcc->parent_reset(ds);
+
+    env->pc_w = 0;
+    env->sregI = 1;
+    env->sregC = 0;
+    env->sregZ = 0;
+    env->sregN = 0;
+    env->sregV = 0;
+    env->sregS = 0;
+    env->sregH = 0;
+    env->sregT = 0;
+
+    env->rampD = 0;
+    env->rampX = 0;
+    env->rampY = 0;
+    env->rampZ = 0;
+    env->eind = 0;
+    env->sp = 0;
+
+    env->skip = 0;
+
+    memset(env->r, 0, sizeof(env->r));
+}
+
+static void avr_cpu_disas_set_info(CPUState *cpu, disassemble_info *info)
+{
+    info->mach = bfd_arch_avr;
+    info->print_insn = avr_print_insn;
+}
+
+static void avr_cpu_realizefn(DeviceState *dev, Error **errp)
+{
+    CPUState *cs = CPU(dev);
+    AVRCPUClass *mcc = AVR_CPU_GET_CLASS(dev);
+    Error *local_err = NULL;
+
+    cpu_exec_realizefn(cs, &local_err);
+    if (local_err != NULL) {
+        error_propagate(errp, local_err);
+        return;
+    }
+    qemu_init_vcpu(cs);
+    cpu_reset(cs);
+
+    mcc->parent_realize(dev, errp);
+}
+
+static void avr_cpu_set_int(void *opaque, int irq, int level)
+{
+    AVRCPU *cpu = opaque;
+    CPUAVRState *env = &cpu->env;
+    CPUState *cs = CPU(cpu);
+    uint64_t mask = (1ull << irq);
+
+    if (level) {
+        env->intsrc |= mask;
+        cpu_interrupt(cs, CPU_INTERRUPT_HARD);
+    } else {
+        env->intsrc &= ~mask;
+        if (env->intsrc == 0) {
+            cpu_reset_interrupt(cs, CPU_INTERRUPT_HARD);
+        }
+    }
+}
+
+static void avr_cpu_initfn(Object *obj)
+{
+    AVRCPU *cpu = AVR_CPU(obj);
+
+    cpu_set_cpustate_pointers(cpu);
+
+    /* Set the number of interrupts supported by the CPU. */
+    qdev_init_gpio_in(DEVICE(cpu), avr_cpu_set_int,
+                      sizeof(cpu->env.intsrc) * 8);
+}
+
+static ObjectClass *avr_cpu_class_by_name(const char *cpu_model)
+{
+    ObjectClass *oc;
+
+    oc = object_class_by_name(cpu_model);
+    if (object_class_dynamic_cast(oc, TYPE_AVR_CPU) == NULL ||
+        object_class_is_abstract(oc)) {
+        oc = NULL;
+    }
+    return oc;
+}
+
+static void avr_cpu_dump_state(CPUState *cs, FILE *f, int flags)
+{
+    AVRCPU *cpu = AVR_CPU(cs);
+    CPUAVRState *env = &cpu->env;
+    int i;
+
+    qemu_fprintf(f, "\n");
+    qemu_fprintf(f, "PC:    %06x\n", env->pc_w * 2); /* PC points to words */
+    qemu_fprintf(f, "SP:      %04x\n", env->sp);
+    qemu_fprintf(f, "rampD:     %02x\n", env->rampD >> 16);
+    qemu_fprintf(f, "rampX:     %02x\n", env->rampX >> 16);
+    qemu_fprintf(f, "rampY:     %02x\n", env->rampY >> 16);
+    qemu_fprintf(f, "rampZ:     %02x\n", env->rampZ >> 16);
+    qemu_fprintf(f, "EIND:      %02x\n", env->eind >> 16);
+    qemu_fprintf(f, "X:       %02x%02x\n", env->r[27], env->r[26]);
+    qemu_fprintf(f, "Y:       %02x%02x\n", env->r[29], env->r[28]);
+    qemu_fprintf(f, "Z:       %02x%02x\n", env->r[31], env->r[30]);
+    qemu_fprintf(f, "SREG:    [ %c %c %c %c %c %c %c %c ]\n",
+                 env->sregI ? 'I' : '-',
+                 env->sregT ? 'T' : '-',
+                 env->sregH ? 'H' : '-',
+                 env->sregS ? 'S' : '-',
+                 env->sregV ? 'V' : '-',
+                 env->sregN ? '-' : 'N', /* Zf has negative logic */
+                 env->sregZ ? 'Z' : '-',
+                 env->sregC ? 'I' : '-');
+    qemu_fprintf(f, "SKIP:    %02x\n", env->skip);
+
+    qemu_fprintf(f, "\n");
+    for (i = 0; i < ARRAY_SIZE(env->r); i++) {
+        qemu_fprintf(f, "R[%02d]:  %02x   ", i, env->r[i]);
+
+        if ((i % 8) == 7) {
+            qemu_fprintf(f, "\n");
+        }
+    }
+    qemu_fprintf(f, "\n");
+}
+
+static void avr_cpu_class_init(ObjectClass *oc, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(oc);
+    CPUClass *cc = CPU_CLASS(oc);
+    AVRCPUClass *mcc = AVR_CPU_CLASS(oc);
+
+    mcc->parent_realize = dc->realize;
+    dc->realize = avr_cpu_realizefn;
+
+    device_class_set_parent_reset(dc, avr_cpu_reset, &mcc->parent_reset);
+
+    cc->class_by_name = avr_cpu_class_by_name;
+
+    cc->has_work = avr_cpu_has_work;
+    cc->do_interrupt = avr_cpu_do_interrupt;
+    cc->cpu_exec_interrupt = avr_cpu_exec_interrupt;
+    cc->dump_state = avr_cpu_dump_state;
+    cc->set_pc = avr_cpu_set_pc;
+    cc->memory_rw_debug = avr_cpu_memory_rw_debug;
+    cc->get_phys_page_debug = avr_cpu_get_phys_page_debug;
+    cc->tlb_fill = avr_cpu_tlb_fill;
+    cc->vmsd = &vms_avr_cpu;
+    cc->disas_set_info = avr_cpu_disas_set_info;
+    cc->tcg_initialize = avr_cpu_tcg_init;
+    cc->synchronize_from_tb = avr_cpu_synchronize_from_tb;
+    cc->gdb_read_register = avr_cpu_gdb_read_register;
+    cc->gdb_write_register = avr_cpu_gdb_write_register;
+    cc->gdb_num_core_regs = 35;
+    cc->gdb_core_xml_file = "avr-cpu.xml";
+}
+
+/*
+ * Setting features of AVR core type avr5
+ * --------------------------------------
+ *
+ * This type of AVR core is present in the following AVR MCUs:
+ *
+ * ata5702m322, ata5782, ata5790, ata5790n, ata5791, ata5795, ata5831, ata6613c,
+ * ata6614q, ata8210, ata8510, atmega16, atmega16a, atmega161, atmega162,
+ * atmega163, atmega164a, atmega164p, atmega164pa, atmega165, atmega165a,
+ * atmega165p, atmega165pa, atmega168, atmega168a, atmega168p, atmega168pa,
+ * atmega168pb, atmega169, atmega169a, atmega169p, atmega169pa, atmega16hvb,
+ * atmega16hvbrevb, atmega16m1, atmega16u4, atmega32a, atmega32, atmega323,
+ * atmega324a, atmega324p, atmega324pa, atmega325, atmega325a, atmega325p,
+ * atmega325pa, atmega3250, atmega3250a, atmega3250p, atmega3250pa, atmega328,
+ * atmega328p, atmega328pb, atmega329, atmega329a, atmega329p, atmega329pa,
+ * atmega3290, atmega3290a, atmega3290p, atmega3290pa, atmega32c1, atmega32m1,
+ * atmega32u4, atmega32u6, atmega406, atmega64, atmega64a, atmega640, atmega644,
+ * atmega644a, atmega644p, atmega644pa, atmega645, atmega645a, atmega645p,
+ * atmega6450, atmega6450a, atmega6450p, atmega649, atmega649a, atmega649p,
+ * atmega6490, atmega16hva, atmega16hva2, atmega32hvb, atmega6490a, atmega6490p,
+ * atmega64c1, atmega64m1, atmega64hve, atmega64hve2, atmega64rfr2,
+ * atmega644rfr2, atmega32hvbrevb, at90can32, at90can64, at90pwm161, at90pwm216,
+ * at90pwm316, at90scr100, at90usb646, at90usb647, at94k, m3000
+ */
+static void avr_avr5_initfn(Object *obj)
+{
+    AVRCPU *cpu = AVR_CPU(obj);
+    CPUAVRState *env = &cpu->env;
+
+    set_avr_feature(env, AVR_FEATURE_LPM);
+    set_avr_feature(env, AVR_FEATURE_IJMP_ICALL);
+    set_avr_feature(env, AVR_FEATURE_ADIW_SBIW);
+    set_avr_feature(env, AVR_FEATURE_SRAM);
+    set_avr_feature(env, AVR_FEATURE_BREAK);
+
+    set_avr_feature(env, AVR_FEATURE_2_BYTE_PC);
+    set_avr_feature(env, AVR_FEATURE_2_BYTE_SP);
+    set_avr_feature(env, AVR_FEATURE_JMP_CALL);
+    set_avr_feature(env, AVR_FEATURE_LPMX);
+    set_avr_feature(env, AVR_FEATURE_MOVW);
+    set_avr_feature(env, AVR_FEATURE_MUL);
+}
+
+/*
+ * Setting features of AVR core type avr51
+ * --------------------------------------
+ *
+ * This type of AVR core is present in the following AVR MCUs:
+ *
+ * atmega128, atmega128a, atmega1280, atmega1281, atmega1284, atmega1284p,
+ * atmega128rfa1, atmega128rfr2, atmega1284rfr2, at90can128, at90usb1286,
+ * at90usb1287
+ */
+static void avr_avr51_initfn(Object *obj)
+{
+    AVRCPU *cpu = AVR_CPU(obj);
+    CPUAVRState *env = &cpu->env;
+
+    set_avr_feature(env, AVR_FEATURE_LPM);
+    set_avr_feature(env, AVR_FEATURE_IJMP_ICALL);
+    set_avr_feature(env, AVR_FEATURE_ADIW_SBIW);
+    set_avr_feature(env, AVR_FEATURE_SRAM);
+    set_avr_feature(env, AVR_FEATURE_BREAK);
+
+    set_avr_feature(env, AVR_FEATURE_2_BYTE_PC);
+    set_avr_feature(env, AVR_FEATURE_2_BYTE_SP);
+    set_avr_feature(env, AVR_FEATURE_RAMPZ);
+    set_avr_feature(env, AVR_FEATURE_ELPMX);
+    set_avr_feature(env, AVR_FEATURE_ELPM);
+    set_avr_feature(env, AVR_FEATURE_JMP_CALL);
+    set_avr_feature(env, AVR_FEATURE_LPMX);
+    set_avr_feature(env, AVR_FEATURE_MOVW);
+    set_avr_feature(env, AVR_FEATURE_MUL);
+}
+
+/*
+ * Setting features of AVR core type avr6
+ * --------------------------------------
+ *
+ * This type of AVR core is present in the following AVR MCUs:
+ *
+ * atmega2560, atmega2561, atmega256rfr2, atmega2564rfr2
+ */
+static void avr_avr6_initfn(Object *obj)
+{
+    AVRCPU *cpu = AVR_CPU(obj);
+    CPUAVRState *env = &cpu->env;
+
+    set_avr_feature(env, AVR_FEATURE_LPM);
+    set_avr_feature(env, AVR_FEATURE_IJMP_ICALL);
+    set_avr_feature(env, AVR_FEATURE_ADIW_SBIW);
+    set_avr_feature(env, AVR_FEATURE_SRAM);
+    set_avr_feature(env, AVR_FEATURE_BREAK);
+
+    set_avr_feature(env, AVR_FEATURE_3_BYTE_PC);
+    set_avr_feature(env, AVR_FEATURE_2_BYTE_SP);
+    set_avr_feature(env, AVR_FEATURE_RAMPZ);
+    set_avr_feature(env, AVR_FEATURE_EIJMP_EICALL);
+    set_avr_feature(env, AVR_FEATURE_ELPMX);
+    set_avr_feature(env, AVR_FEATURE_ELPM);
+    set_avr_feature(env, AVR_FEATURE_JMP_CALL);
+    set_avr_feature(env, AVR_FEATURE_LPMX);
+    set_avr_feature(env, AVR_FEATURE_MOVW);
+    set_avr_feature(env, AVR_FEATURE_MUL);
+}
+
+typedef struct AVRCPUInfo {
+    const char *name;
+    void (*initfn)(Object *obj);
+} AVRCPUInfo;
+
+
+static void avr_cpu_list_entry(gpointer data, gpointer user_data)
+{
+    const char *typename = object_class_get_name(OBJECT_CLASS(data));
+
+    qemu_printf("%s\n", typename);
+}
+
+void avr_cpu_list(void)
+{
+    GSList *list;
+    list = object_class_get_list_sorted(TYPE_AVR_CPU, false);
+    g_slist_foreach(list, avr_cpu_list_entry, NULL);
+    g_slist_free(list);
+}
+
+#define DEFINE_AVR_CPU_TYPE(model, initfn) \
+    { \
+        .parent = TYPE_AVR_CPU, \
+        .instance_init = initfn, \
+        .name = AVR_CPU_TYPE_NAME(model), \
+    }
+
+static const TypeInfo avr_cpu_type_info[] = {
+    {
+        .name = TYPE_AVR_CPU,
+        .parent = TYPE_CPU,
+        .instance_size = sizeof(AVRCPU),
+        .instance_init = avr_cpu_initfn,
+        .class_size = sizeof(AVRCPUClass),
+        .class_init = avr_cpu_class_init,
+        .abstract = true,
+    },
+    DEFINE_AVR_CPU_TYPE("avr5", avr_avr5_initfn),
+    DEFINE_AVR_CPU_TYPE("avr51", avr_avr51_initfn),
+    DEFINE_AVR_CPU_TYPE("avr6", avr_avr6_initfn),
+};
+
+DEFINE_TYPES(avr_cpu_type_info)
diff --git a/target/avr/cpu.h b/target/avr/cpu.h
new file mode 100644
index 0000000000..d148e8c75a
--- /dev/null
+++ b/target/avr/cpu.h
@@ -0,0 +1,256 @@
+/*
+ * QEMU AVR CPU
+ *
+ * Copyright (c) 2016-2020 Michael Rolnik
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see
+ * <http://www.gnu.org/licenses/lgpl-2.1.html>
+ */
+
+#ifndef QEMU_AVR_CPU_H
+#define QEMU_AVR_CPU_H
+
+#include "cpu-qom.h"
+#include "exec/cpu-defs.h"
+
+#ifdef CONFIG_USER_ONLY
+#error "AVR 8-bit does not support user mode"
+#endif
+
+#define AVR_CPU_TYPE_SUFFIX "-" TYPE_AVR_CPU
+#define AVR_CPU_TYPE_NAME(name) (name AVR_CPU_TYPE_SUFFIX)
+#define CPU_RESOLVING_TYPE TYPE_AVR_CPU
+
+#define TCG_GUEST_DEFAULT_MO 0
+
+/*
+ * AVR has two memory spaces, data & code.
+ * e.g. both have 0 address
+ * ST/LD instructions access data space
+ * LPM/SPM and instruction fetching access code memory space
+ */
+#define MMU_CODE_IDX 0
+#define MMU_DATA_IDX 1
+
+#define EXCP_RESET 1
+#define EXCP_INT(n) (EXCP_RESET + (n) + 1)
+
+/* Number of CPU registers */
+#define NUMBER_OF_CPU_REGISTERS 32
+/* Number of IO registers accessible by ld/st/in/out */
+#define NUMBER_OF_IO_REGISTERS 64
+
+/*
+ * Offsets of AVR memory regions in host memory space.
+ *
+ * This is needed because the AVR has separate code and data address
+ * spaces that both have start from zero but have to go somewhere in
+ * host memory.
+ *
+ * It's also useful to know where some things are, like the IO registers.
+ */
+/* Flash program memory */
+#define OFFSET_CODE 0x00000000
+/* CPU registers, IO registers, and SRAM */
+#define OFFSET_DATA 0x00800000
+/* CPU registers specifically, these are mapped at the start of data */
+#define OFFSET_CPU_REGISTERS OFFSET_DATA
+/*
+ * IO registers, including status register, stack pointer, and memory
+ * mapped peripherals, mapped just after CPU registers
+ */
+#define OFFSET_IO_REGISTERS (OFFSET_DATA + NUMBER_OF_CPU_REGISTERS)
+
+typedef enum AVRFeature {
+    AVR_FEATURE_SRAM,
+
+    AVR_FEATURE_1_BYTE_PC,
+    AVR_FEATURE_2_BYTE_PC,
+    AVR_FEATURE_3_BYTE_PC,
+
+    AVR_FEATURE_1_BYTE_SP,
+    AVR_FEATURE_2_BYTE_SP,
+
+    AVR_FEATURE_BREAK,
+    AVR_FEATURE_DES,
+    AVR_FEATURE_RMW, /* Read Modify Write - XCH LAC LAS LAT */
+
+    AVR_FEATURE_EIJMP_EICALL,
+    AVR_FEATURE_IJMP_ICALL,
+    AVR_FEATURE_JMP_CALL,
+
+    AVR_FEATURE_ADIW_SBIW,
+
+    AVR_FEATURE_SPM,
+    AVR_FEATURE_SPMX,
+
+    AVR_FEATURE_ELPMX,
+    AVR_FEATURE_ELPM,
+    AVR_FEATURE_LPMX,
+    AVR_FEATURE_LPM,
+
+    AVR_FEATURE_MOVW,
+    AVR_FEATURE_MUL,
+    AVR_FEATURE_RAMPD,
+    AVR_FEATURE_RAMPX,
+    AVR_FEATURE_RAMPY,
+    AVR_FEATURE_RAMPZ,
+} AVRFeature;
+
+typedef struct CPUAVRState CPUAVRState;
+
+struct CPUAVRState {
+    uint32_t pc_w; /* 0x003fffff up to 22 bits */
+
+    uint32_t sregC; /* 0x00000001 1 bit */
+    uint32_t sregZ; /* 0x00000001 1 bit */
+    uint32_t sregN; /* 0x00000001 1 bit */
+    uint32_t sregV; /* 0x00000001 1 bit */
+    uint32_t sregS; /* 0x00000001 1 bit */
+    uint32_t sregH; /* 0x00000001 1 bit */
+    uint32_t sregT; /* 0x00000001 1 bit */
+    uint32_t sregI; /* 0x00000001 1 bit */
+
+    uint32_t rampD; /* 0x00ff0000 8 bits */
+    uint32_t rampX; /* 0x00ff0000 8 bits */
+    uint32_t rampY; /* 0x00ff0000 8 bits */
+    uint32_t rampZ; /* 0x00ff0000 8 bits */
+    uint32_t eind; /* 0x00ff0000 8 bits */
+
+    uint32_t r[NUMBER_OF_CPU_REGISTERS]; /* 8 bits each */
+    uint32_t sp; /* 16 bits */
+
+    uint32_t skip; /* if set skip instruction */
+
+    uint64_t intsrc; /* interrupt sources */
+    bool fullacc; /* CPU/MEM if true MEM only otherwise */
+
+    uint64_t features;
+};
+
+/**
+ *  AVRCPU:
+ *  @env: #CPUAVRState
+ *
+ *  A AVR CPU.
+ */
+typedef struct AVRCPU {
+    /*< private >*/
+    CPUState parent_obj;
+    /*< public >*/
+
+    CPUNegativeOffsetState neg;
+    CPUAVRState env;
+} AVRCPU;
+
+extern const struct VMStateDescription vms_avr_cpu;
+
+void avr_cpu_do_interrupt(CPUState *cpu);
+bool avr_cpu_exec_interrupt(CPUState *cpu, int int_req);
+hwaddr avr_cpu_get_phys_page_debug(CPUState *cpu, vaddr addr);
+int avr_cpu_gdb_read_register(CPUState *cpu, GByteArray *buf, int reg);
+int avr_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg);
+int avr_print_insn(bfd_vma addr, disassemble_info *info);
+
+static inline int avr_feature(CPUAVRState *env, AVRFeature feature)
+{
+    return (env->features & (1U << feature)) != 0;
+}
+
+static inline void set_avr_feature(CPUAVRState *env, int feature)
+{
+    env->features |= (1U << feature);
+}
+
+#define cpu_list avr_cpu_list
+#define cpu_signal_handler cpu_avr_signal_handler
+#define cpu_mmu_index avr_cpu_mmu_index
+
+static inline int avr_cpu_mmu_index(CPUAVRState *env, bool ifetch)
+{
+    return ifetch ? MMU_CODE_IDX : MMU_DATA_IDX;
+}
+
+void avr_cpu_tcg_init(void);
+
+void avr_cpu_list(void);
+int cpu_avr_exec(CPUState *cpu);
+int cpu_avr_signal_handler(int host_signum, void *pinfo, void *puc);
+int avr_cpu_memory_rw_debug(CPUState *cs, vaddr address, uint8_t *buf,
+                            int len, bool is_write);
+
+enum {
+    TB_FLAGS_FULL_ACCESS = 1,
+    TB_FLAGS_SKIP = 2,
+};
+
+static inline void cpu_get_tb_cpu_state(CPUAVRState *env, target_ulong *pc,
+                                        target_ulong *cs_base, uint32_t *pflags)
+{
+    uint32_t flags = 0;
+
+    *pc = env->pc_w * 2;
+    *cs_base = 0;
+
+    if (env->fullacc) {
+        flags |= TB_FLAGS_FULL_ACCESS;
+    }
+    if (env->skip) {
+        flags |= TB_FLAGS_SKIP;
+    }
+
+    *pflags = flags;
+}
+
+static inline int cpu_interrupts_enabled(CPUAVRState *env)
+{
+    return env->sregI != 0;
+}
+
+static inline uint8_t cpu_get_sreg(CPUAVRState *env)
+{
+    uint8_t sreg;
+    sreg = (env->sregC) << 0
+         | (env->sregZ) << 1
+         | (env->sregN) << 2
+         | (env->sregV) << 3
+         | (env->sregS) << 4
+         | (env->sregH) << 5
+         | (env->sregT) << 6
+         | (env->sregI) << 7;
+    return sreg;
+}
+
+static inline void cpu_set_sreg(CPUAVRState *env, uint8_t sreg)
+{
+    env->sregC = (sreg >> 0) & 0x01;
+    env->sregZ = (sreg >> 1) & 0x01;
+    env->sregN = (sreg >> 2) & 0x01;
+    env->sregV = (sreg >> 3) & 0x01;
+    env->sregS = (sreg >> 4) & 0x01;
+    env->sregH = (sreg >> 5) & 0x01;
+    env->sregT = (sreg >> 6) & 0x01;
+    env->sregI = (sreg >> 7) & 0x01;
+}
+
+bool avr_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
+                      MMUAccessType access_type, int mmu_idx,
+                      bool probe, uintptr_t retaddr);
+
+typedef CPUAVRState CPUArchState;
+typedef AVRCPU ArchCPU;
+
+#include "exec/cpu-all.h"
+
+#endif /* !defined (QEMU_AVR_CPU_H) */
diff --git a/target/avr/disas.c b/target/avr/disas.c
new file mode 100644
index 0000000000..8e1bac4d76
--- /dev/null
+++ b/target/avr/disas.c
@@ -0,0 +1,245 @@
+/*
+ * AVR disassembler
+ *
+ * Copyright (c) 2019-2020 Richard Henderson <rth@twiddle.net>
+ * Copyright (c) 2019-2020 Michael Rolnik <mrolnik@gmail.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "qemu/osdep.h"
+#include "cpu.h"
+
+typedef struct {
+    disassemble_info *info;
+    uint16_t next_word;
+    bool next_word_used;
+} DisasContext;
+
+static int to_regs_16_31_by_one(DisasContext *ctx, int indx)
+{
+    return 16 + (indx % 16);
+}
+
+static int to_regs_16_23_by_one(DisasContext *ctx, int indx)
+{
+    return 16 + (indx % 8);
+}
+
+static int to_regs_24_30_by_two(DisasContext *ctx, int indx)
+{
+    return 24 + (indx % 4) * 2;
+}
+
+static int to_regs_00_30_by_two(DisasContext *ctx, int indx)
+{
+    return (indx % 16) * 2;
+}
+
+static uint16_t next_word(DisasContext *ctx)
+{
+    ctx->next_word_used = true;
+    return ctx->next_word;
+}
+
+static int append_16(DisasContext *ctx, int x)
+{
+    return x << 16 | next_word(ctx);
+}
+
+/* Include the auto-generated decoder.  */
+static bool decode_insn(DisasContext *ctx, uint16_t insn);
+#include "decode_insn.inc.c"
+
+#define output(mnemonic, format, ...) \
+    (pctx->info->fprintf_func(pctx->info->stream, "%-9s " format, \
+                              mnemonic, ##__VA_ARGS__))
+
+int avr_print_insn(bfd_vma addr, disassemble_info *info)
+{
+    DisasContext ctx;
+    DisasContext *pctx = &ctx;
+    bfd_byte buffer[4];
+    uint16_t insn;
+    int status;
+
+    ctx.info = info;
+
+    status = info->read_memory_func(addr, buffer, 4, info);
+    if (status != 0) {
+        info->memory_error_func(status, addr, info);
+        return -1;
+    }
+    insn = bfd_getl16(buffer);
+    ctx.next_word = bfd_getl16(buffer + 2);
+    ctx.next_word_used = false;
+
+    if (!decode_insn(&ctx, insn)) {
+        output(".db", "0x%02x, 0x%02x", buffer[0], buffer[1]);
+    }
+
+    return ctx.next_word_used ? 4 : 2;
+}
+
+
+#define INSN(opcode, format, ...)                                       \
+static bool trans_##opcode(DisasContext *pctx, arg_##opcode * a)        \
+{                                                                       \
+    output(#opcode, format, ##__VA_ARGS__);                             \
+    return true;                                                        \
+}
+
+#define INSN_MNEMONIC(opcode, mnemonic, format, ...)                    \
+static bool trans_##opcode(DisasContext *pctx, arg_##opcode * a)        \
+{                                                                       \
+    output(mnemonic, format, ##__VA_ARGS__);                            \
+    return true;                                                        \
+}
+
+/*
+ *   C       Z       N       V       S       H       T       I
+ *   0       1       2       3       4       5       6       7
+ */
+static const char brbc[][5] = {
+    "BRCC", "BRNE", "BRPL", "BRVC", "BRGE", "BRHC", "BRTC", "BRID"
+};
+
+static const char brbs[][5] = {
+    "BRCS", "BREQ", "BRMI", "BRVS", "BRLT", "BRHS", "BRTS", "BRIE"
+};
+
+static const char bset[][4] = {
+    "SEC",  "SEZ",  "SEN",  "SEZ",  "SES",  "SEH",  "SET",  "SEI"
+};
+
+static const char bclr[][4] = {
+    "CLC",  "CLZ",  "CLN",  "CLZ",  "CLS",  "CLH",  "CLT",  "CLI"
+};
+
+/*
+ * Arithmetic Instructions
+ */
+INSN(ADD,    "r%d, r%d", a->rd, a->rr)
+INSN(ADC,    "r%d, r%d", a->rd, a->rr)
+INSN(ADIW,   "r%d:r%d, %d", a->rd + 1, a->rd, a->imm)
+INSN(SUB,    "r%d, r%d", a->rd, a->rr)
+INSN(SUBI,   "r%d, %d", a->rd, a->imm)
+INSN(SBC,    "r%d, r%d", a->rd, a->rr)
+INSN(SBCI,   "r%d, %d", a->rd, a->imm)
+INSN(SBIW,   "r%d:r%d, %d", a->rd + 1, a->rd, a->imm)
+INSN(AND,    "r%d, r%d", a->rd, a->rr)
+INSN(ANDI,   "r%d, %d", a->rd, a->imm)
+INSN(OR,     "r%d, r%d", a->rd, a->rr)
+INSN(ORI,    "r%d, %d", a->rd, a->imm)
+INSN(EOR,    "r%d, r%d", a->rd, a->rr)
+INSN(COM,    "r%d", a->rd)
+INSN(NEG,    "r%d", a->rd)
+INSN(INC,    "r%d", a->rd)
+INSN(DEC,    "r%d", a->rd)
+INSN(MUL,    "r%d, r%d", a->rd, a->rr)
+INSN(MULS,   "r%d, r%d", a->rd, a->rr)
+INSN(MULSU,  "r%d, r%d", a->rd, a->rr)
+INSN(FMUL,   "r%d, r%d", a->rd, a->rr)
+INSN(FMULS,  "r%d, r%d", a->rd, a->rr)
+INSN(FMULSU, "r%d, r%d", a->rd, a->rr)
+INSN(DES,    "%d", a->imm)
+
+/*
+ * Branch Instructions
+ */
+INSN(RJMP,   ".%+d", a->imm * 2)
+INSN(IJMP,   "")
+INSN(EIJMP,  "")
+INSN(JMP,    "0x%x", a->imm * 2)
+INSN(RCALL,  ".%+d", a->imm * 2)
+INSN(ICALL,  "")
+INSN(EICALL, "")
+INSN(CALL,   "0x%x", a->imm * 2)
+INSN(RET,    "")
+INSN(RETI,   "")
+INSN(CPSE,   "r%d, r%d", a->rd, a->rr)
+INSN(CP,     "r%d, r%d", a->rd, a->rr)
+INSN(CPC,    "r%d, r%d", a->rd, a->rr)
+INSN(CPI,    "r%d, %d", a->rd, a->imm)
+INSN(SBRC,   "r%d, %d", a->rr, a->bit)
+INSN(SBRS,   "r%d, %d", a->rr, a->bit)
+INSN(SBIC,   "$%d, %d", a->reg, a->bit)
+INSN(SBIS,   "$%d, %d", a->reg, a->bit)
+INSN_MNEMONIC(BRBS,  brbs[a->bit], ".%+d", a->imm * 2)
+INSN_MNEMONIC(BRBC,  brbc[a->bit], ".%+d", a->imm * 2)
+
+/*
+ * Data Transfer Instructions
+ */
+INSN(MOV,    "r%d, r%d", a->rd, a->rr)
+INSN(MOVW,   "r%d:r%d, r%d:r%d", a->rd + 1, a->rd, a->rr + 1, a->rr)
+INSN(LDI,    "r%d, %d", a->rd, a->imm)
+INSN(LDS,    "r%d, %d", a->rd, a->imm)
+INSN(LDX1,   "r%d, X", a->rd)
+INSN(LDX2,   "r%d, X+", a->rd)
+INSN(LDX3,   "r%d, -X", a->rd)
+INSN(LDY2,   "r%d, Y+", a->rd)
+INSN(LDY3,   "r%d, -Y", a->rd)
+INSN(LDZ2,   "r%d, Z+", a->rd)
+INSN(LDZ3,   "r%d, -Z", a->rd)
+INSN(LDDY,   "r%d, Y+%d", a->rd, a->imm)
+INSN(LDDZ,   "r%d, Z+%d", a->rd, a->imm)
+INSN(STS,    "%d, r%d", a->imm, a->rd)
+INSN(STX1,   "X, r%d", a->rr)
+INSN(STX2,   "X+, r%d", a->rr)
+INSN(STX3,   "-X, r%d", a->rr)
+INSN(STY2,   "Y+, r%d", a->rd)
+INSN(STY3,   "-Y, r%d", a->rd)
+INSN(STZ2,   "Z+, r%d", a->rd)
+INSN(STZ3,   "-Z, r%d", a->rd)
+INSN(STDY,   "Y+%d, r%d", a->imm, a->rd)
+INSN(STDZ,   "Z+%d, r%d", a->imm, a->rd)
+INSN(LPM1,   "")
+INSN(LPM2,   "r%d, Z", a->rd)
+INSN(LPMX,   "r%d, Z+", a->rd)
+INSN(ELPM1,  "")
+INSN(ELPM2,  "r%d, Z", a->rd)
+INSN(ELPMX,  "r%d, Z+", a->rd)
+INSN(SPM,    "")
+INSN(SPMX,   "Z+")
+INSN(IN,     "r%d, $%d", a->rd, a->imm)
+INSN(OUT,    "$%d, r%d", a->imm, a->rd)
+INSN(PUSH,   "r%d", a->rd)
+INSN(POP,    "r%d", a->rd)
+INSN(XCH,    "Z, r%d", a->rd)
+INSN(LAC,    "Z, r%d", a->rd)
+INSN(LAS,    "Z, r%d", a->rd)
+INSN(LAT,    "Z, r%d", a->rd)
+
+/*
+ * Bit and Bit-test Instructions
+ */
+INSN(LSR,    "r%d", a->rd)
+INSN(ROR,    "r%d", a->rd)
+INSN(ASR,    "r%d", a->rd)
+INSN(SWAP,   "r%d", a->rd)
+INSN(SBI,    "$%d, %d", a->reg, a->bit)
+INSN(CBI,    "%d, %d", a->reg, a->bit)
+INSN(BST,    "r%d, %d", a->rd, a->bit)
+INSN(BLD,    "r%d, %d", a->rd, a->bit)
+INSN_MNEMONIC(BSET,  bset[a->bit], "")
+INSN_MNEMONIC(BCLR,  bclr[a->bit], "")
+
+/*
+ * MCU Control Instructions
+ */
+INSN(BREAK,  "")
+INSN(NOP,    "")
+INSN(SLEEP,  "")
+INSN(WDR,    "")
diff --git a/target/avr/gdbstub.c b/target/avr/gdbstub.c
new file mode 100644
index 0000000000..c28ed67efe
--- /dev/null
+++ b/target/avr/gdbstub.c
@@ -0,0 +1,84 @@
+/*
+ * QEMU AVR gdbstub
+ *
+ * Copyright (c) 2016-2020 Michael Rolnik
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see
+ * <http://www.gnu.org/licenses/lgpl-2.1.html>
+ */
+
+#include "qemu/osdep.h"
+#include "exec/gdbstub.h"
+
+int avr_cpu_gdb_read_register(CPUState *cs, GByteArray *mem_buf, int n)
+{
+    AVRCPU *cpu = AVR_CPU(cs);
+    CPUAVRState *env = &cpu->env;
+
+    /*  R */
+    if (n < 32) {
+        return gdb_get_reg8(mem_buf, env->r[n]);
+    }
+
+    /*  SREG */
+    if (n == 32) {
+        uint8_t sreg = cpu_get_sreg(env);
+
+        return gdb_get_reg8(mem_buf, sreg);
+    }
+
+    /*  SP */
+    if (n == 33) {
+        return gdb_get_reg16(mem_buf, env->sp & 0x0000ffff);
+    }
+
+    /*  PC */
+    if (n == 34) {
+        return gdb_get_reg32(mem_buf, env->pc_w * 2);
+    }
+
+    return 0;
+}
+
+int avr_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n)
+{
+    AVRCPU *cpu = AVR_CPU(cs);
+    CPUAVRState *env = &cpu->env;
+
+    /*  R */
+    if (n < 32) {
+        env->r[n] = *mem_buf;
+        return 1;
+    }
+
+    /*  SREG */
+    if (n == 32) {
+        cpu_set_sreg(env, *mem_buf);
+        return 1;
+    }
+
+    /*  SP */
+    if (n == 33) {
+        env->sp = lduw_p(mem_buf);
+        return 2;
+    }
+
+    /*  PC */
+    if (n == 34) {
+        env->pc_w = ldl_p(mem_buf) / 2;
+        return 4;
+    }
+
+    return 0;
+}
diff --git a/target/avr/helper.c b/target/avr/helper.c
new file mode 100644
index 0000000000..d96d14372b
--- /dev/null
+++ b/target/avr/helper.c
@@ -0,0 +1,348 @@
+/*
+ * QEMU AVR CPU helpers
+ *
+ * Copyright (c) 2016-2020 Michael Rolnik
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see
+ * <http://www.gnu.org/licenses/lgpl-2.1.html>
+ */
+
+#include "qemu/osdep.h"
+#include "cpu.h"
+#include "exec/exec-all.h"
+#include "exec/address-spaces.h"
+#include "exec/helper-proto.h"
+
+bool avr_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
+{
+    bool ret = false;
+    CPUClass *cc = CPU_GET_CLASS(cs);
+    AVRCPU *cpu = AVR_CPU(cs);
+    CPUAVRState *env = &cpu->env;
+
+    if (interrupt_request & CPU_INTERRUPT_RESET) {
+        if (cpu_interrupts_enabled(env)) {
+            cs->exception_index = EXCP_RESET;
+            cc->do_interrupt(cs);
+
+            cs->interrupt_request &= ~CPU_INTERRUPT_RESET;
+
+            ret = true;
+        }
+    }
+    if (interrupt_request & CPU_INTERRUPT_HARD) {
+        if (cpu_interrupts_enabled(env) && env->intsrc != 0) {
+            int index = ctz32(env->intsrc);
+            cs->exception_index = EXCP_INT(index);
+            cc->do_interrupt(cs);
+
+            env->intsrc &= env->intsrc - 1; /* clear the interrupt */
+            cs->interrupt_request &= ~CPU_INTERRUPT_HARD;
+
+            ret = true;
+        }
+    }
+    return ret;
+}
+
+void avr_cpu_do_interrupt(CPUState *cs)
+{
+    AVRCPU *cpu = AVR_CPU(cs);
+    CPUAVRState *env = &cpu->env;
+
+    uint32_t ret = env->pc_w;
+    int vector = 0;
+    int size = avr_feature(env, AVR_FEATURE_JMP_CALL) ? 2 : 1;
+    int base = 0;
+
+    if (cs->exception_index == EXCP_RESET) {
+        vector = 0;
+    } else if (env->intsrc != 0) {
+        vector = ctz32(env->intsrc) + 1;
+    }
+
+    if (avr_feature(env, AVR_FEATURE_3_BYTE_PC)) {
+        cpu_stb_data(env, env->sp--, (ret & 0x0000ff));
+        cpu_stb_data(env, env->sp--, (ret & 0x00ff00) >> 8);
+        cpu_stb_data(env, env->sp--, (ret & 0xff0000) >> 16);
+    } else if (avr_feature(env, AVR_FEATURE_2_BYTE_PC)) {
+        cpu_stb_data(env, env->sp--, (ret & 0x0000ff));
+        cpu_stb_data(env, env->sp--, (ret & 0x00ff00) >> 8);
+    } else {
+        cpu_stb_data(env, env->sp--, (ret & 0x0000ff));
+    }
+
+    env->pc_w = base + vector * size;
+    env->sregI = 0; /* clear Global Interrupt Flag */
+
+    cs->exception_index = -1;
+}
+
+int avr_cpu_memory_rw_debug(CPUState *cs, vaddr addr, uint8_t *buf,
+                            int len, bool is_write)
+{
+    return cpu_memory_rw_debug(cs, addr, buf, len, is_write);
+}
+
+hwaddr avr_cpu_get_phys_page_debug(CPUState *cs, vaddr addr)
+{
+    return addr; /* I assume 1:1 address correspondance */
+}
+
+bool avr_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
+                      MMUAccessType access_type, int mmu_idx,
+                      bool probe, uintptr_t retaddr)
+{
+    int prot = 0;
+    MemTxAttrs attrs = {};
+    uint32_t paddr;
+
+    address &= TARGET_PAGE_MASK;
+
+    if (mmu_idx == MMU_CODE_IDX) {
+        /* access to code in flash */
+        paddr = OFFSET_CODE + address;
+        prot = PAGE_READ | PAGE_EXEC;
+        if (paddr + TARGET_PAGE_SIZE > OFFSET_DATA) {
+            error_report("execution left flash memory");
+            abort();
+        }
+    } else if (address < NUMBER_OF_CPU_REGISTERS + NUMBER_OF_IO_REGISTERS) {
+        /*
+         * access to CPU registers, exit and rebuilt this TB to use full access
+         * incase it touches specially handled registers like SREG or SP
+         */
+        AVRCPU *cpu = AVR_CPU(cs);
+        CPUAVRState *env = &cpu->env;
+        env->fullacc = 1;
+        cpu_loop_exit_restore(cs, retaddr);
+    } else {
+        /* access to memory. nothing special */
+        paddr = OFFSET_DATA + address;
+        prot = PAGE_READ | PAGE_WRITE;
+    }
+
+    tlb_set_page_with_attrs(cs, address, paddr, attrs, prot,
+                            mmu_idx, TARGET_PAGE_SIZE);
+
+    return true;
+}
+
+/*
+ *  helpers
+ */
+
+void helper_sleep(CPUAVRState *env)
+{
+    CPUState *cs = env_cpu(env);
+
+    cs->exception_index = EXCP_HLT;
+    cpu_loop_exit(cs);
+}
+
+void helper_unsupported(CPUAVRState *env)
+{
+    CPUState *cs = env_cpu(env);
+
+    /*
+     *  I count not find what happens on the real platform, so
+     *  it's EXCP_DEBUG for meanwhile
+     */
+    cs->exception_index = EXCP_DEBUG;
+    if (qemu_loglevel_mask(LOG_UNIMP)) {
+        qemu_log("UNSUPPORTED\n");
+        cpu_dump_state(cs, stderr, 0);
+    }
+    cpu_loop_exit(cs);
+}
+
+void helper_debug(CPUAVRState *env)
+{
+    CPUState *cs = env_cpu(env);
+
+    cs->exception_index = EXCP_DEBUG;
+    cpu_loop_exit(cs);
+}
+
+void helper_break(CPUAVRState *env)
+{
+    CPUState *cs = env_cpu(env);
+
+    cs->exception_index = EXCP_DEBUG;
+    cpu_loop_exit(cs);
+}
+
+void helper_wdr(CPUAVRState *env)
+{
+    CPUState *cs = env_cpu(env);
+
+    /* WD is not implemented yet, placeholder */
+    cs->exception_index = EXCP_DEBUG;
+    cpu_loop_exit(cs);
+}
+
+/*
+ * This function implements IN instruction
+ *
+ * It does the following
+ * a.  if an IO register belongs to CPU, its value is read and returned
+ * b.  otherwise io address is translated to mem address and physical memory
+ *     is read.
+ * c.  it caches the value for sake of SBI, SBIC, SBIS & CBI implementation
+ *
+ */
+target_ulong helper_inb(CPUAVRState *env, uint32_t port)
+{
+    target_ulong data = 0;
+
+    switch (port) {
+    case 0x38: /* RAMPD */
+        data = 0xff & (env->rampD >> 16);
+        break;
+    case 0x39: /* RAMPX */
+        data = 0xff & (env->rampX >> 16);
+        break;
+    case 0x3a: /* RAMPY */
+        data = 0xff & (env->rampY >> 16);
+        break;
+    case 0x3b: /* RAMPZ */
+        data = 0xff & (env->rampZ >> 16);
+        break;
+    case 0x3c: /* EIND */
+        data = 0xff & (env->eind >> 16);
+        break;
+    case 0x3d: /* SPL */
+        data = env->sp & 0x00ff;
+        break;
+    case 0x3e: /* SPH */
+        data = env->sp >> 8;
+        break;
+    case 0x3f: /* SREG */
+        data = cpu_get_sreg(env);
+        break;
+    default:
+        /* not a special register, pass to normal memory access */
+        data = address_space_ldub(&address_space_memory,
+                                  OFFSET_IO_REGISTERS + port,
+                                  MEMTXATTRS_UNSPECIFIED, NULL);
+    }
+
+    return data;
+}
+
+/*
+ *  This function implements OUT instruction
+ *
+ *  It does the following
+ *  a.  if an IO register belongs to CPU, its value is written into the register
+ *  b.  otherwise io address is translated to mem address and physical memory
+ *      is written.
+ *  c.  it caches the value for sake of SBI, SBIC, SBIS & CBI implementation
+ *
+ */
+void helper_outb(CPUAVRState *env, uint32_t port, uint32_t data)
+{
+    data &= 0x000000ff;
+
+    switch (port) {
+    case 0x38: /* RAMPD */
+        if (avr_feature(env, AVR_FEATURE_RAMPD)) {
+            env->rampD = (data & 0xff) << 16;
+        }
+        break;
+    case 0x39: /* RAMPX */
+        if (avr_feature(env, AVR_FEATURE_RAMPX)) {
+            env->rampX = (data & 0xff) << 16;
+        }
+        break;
+    case 0x3a: /* RAMPY */
+        if (avr_feature(env, AVR_FEATURE_RAMPY)) {
+            env->rampY = (data & 0xff) << 16;
+        }
+        break;
+    case 0x3b: /* RAMPZ */
+        if (avr_feature(env, AVR_FEATURE_RAMPZ)) {
+            env->rampZ = (data & 0xff) << 16;
+        }
+        break;
+    case 0x3c: /* EIDN */
+        env->eind = (data & 0xff) << 16;
+        break;
+    case 0x3d: /* SPL */
+        env->sp = (env->sp & 0xff00) | (data);
+        break;
+    case 0x3e: /* SPH */
+        if (avr_feature(env, AVR_FEATURE_2_BYTE_SP)) {
+            env->sp = (env->sp & 0x00ff) | (data << 8);
+        }
+        break;
+    case 0x3f: /* SREG */
+        cpu_set_sreg(env, data);
+        break;
+    default:
+        /* not a special register, pass to normal memory access */
+        address_space_stb(&address_space_memory, OFFSET_IO_REGISTERS + port,
+                          data, MEMTXATTRS_UNSPECIFIED, NULL);
+    }
+}
+
+/*
+ *  this function implements LD instruction when there is a posibility to read
+ *  from a CPU register
+ */
+target_ulong helper_fullrd(CPUAVRState *env, uint32_t addr)
+{
+    uint8_t data;
+
+    env->fullacc = false;
+
+    if (addr < NUMBER_OF_CPU_REGISTERS) {
+        /* CPU registers */
+        data = env->r[addr];
+    } else if (addr < NUMBER_OF_CPU_REGISTERS + NUMBER_OF_IO_REGISTERS) {
+        /* IO registers */
+        data = helper_inb(env, addr - NUMBER_OF_CPU_REGISTERS);
+    } else {
+        /* memory */
+        data = address_space_ldub(&address_space_memory, OFFSET_DATA + addr,
+                                  MEMTXATTRS_UNSPECIFIED, NULL);
+    }
+    return data;
+}
+
+/*
+ *  this function implements ST instruction when there is a posibility to write
+ *  into a CPU register
+ */
+void helper_fullwr(CPUAVRState *env, uint32_t data, uint32_t addr)
+{
+    env->fullacc = false;
+
+    /* Following logic assumes this: */
+    assert(OFFSET_CPU_REGISTERS == OFFSET_DATA);
+    assert(OFFSET_IO_REGISTERS == OFFSET_CPU_REGISTERS +
+                                  NUMBER_OF_CPU_REGISTERS);
+
+    if (addr < NUMBER_OF_CPU_REGISTERS) {
+        /* CPU registers */
+        env->r[addr] = data;
+    } else if (addr < NUMBER_OF_CPU_REGISTERS + NUMBER_OF_IO_REGISTERS) {
+        /* IO registers */
+        helper_outb(env, addr - NUMBER_OF_CPU_REGISTERS, data);
+    } else {
+        /* memory */
+        address_space_stb(&address_space_memory, OFFSET_DATA + addr, data,
+                          MEMTXATTRS_UNSPECIFIED, NULL);
+    }
+}
diff --git a/target/avr/helper.h b/target/avr/helper.h
new file mode 100644
index 0000000000..8e1ae7fda0
--- /dev/null
+++ b/target/avr/helper.h
@@ -0,0 +1,29 @@
+/*
+ * QEMU AVR CPU helpers
+ *
+ * Copyright (c) 2016-2020 Michael Rolnik
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see
+ * <http://www.gnu.org/licenses/lgpl-2.1.html>
+ */
+
+DEF_HELPER_1(wdr, void, env)
+DEF_HELPER_1(debug, void, env)
+DEF_HELPER_1(break, void, env)
+DEF_HELPER_1(sleep, void, env)
+DEF_HELPER_1(unsupported, void, env)
+DEF_HELPER_3(outb, void, env, i32, i32)
+DEF_HELPER_2(inb, tl, env, i32)
+DEF_HELPER_3(fullwr, void, env, i32, i32)
+DEF_HELPER_2(fullrd, tl, env, i32)
diff --git a/target/avr/insn.decode b/target/avr/insn.decode
new file mode 100644
index 0000000000..482c23ad0c
--- /dev/null
+++ b/target/avr/insn.decode
@@ -0,0 +1,187 @@
+#
+# AVR instruction decode definitions.
+#
+# Copyright (c) 2019-2020 Michael Rolnik <mrolnik@gmail.com>
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+#
+# This library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library; if not, see <http://www.gnu.org/licenses/>.
+#
+
+#
+#   regs_16_31_by_one = [16 .. 31]
+#   regs_16_23_by_one = [16 .. 23]
+#   regs_24_30_by_two = [24, 26, 28, 30]
+#   regs_00_30_by_two = [0, 2, 4, 6, 8, .. 30]
+
+%rd             4:5
+%rr             9:1 0:4
+
+%rd_a           4:4                         !function=to_regs_16_31_by_one
+%rd_b           4:3                         !function=to_regs_16_23_by_one
+%rd_c           4:2                         !function=to_regs_24_30_by_two
+%rr_a           0:4                         !function=to_regs_16_31_by_one
+%rr_b           0:3                         !function=to_regs_16_23_by_one
+
+%imm6           6:2 0:4
+%imm8           8:4 0:4
+
+%io_imm         9:2 0:4
+%ldst_d_imm     13:1 10:2 0:3
+
+
+&rd_rr          rd rr
+&rd_imm         rd imm
+
+@op_rd_rr       .... .. . ..... ....        &rd_rr      rd=%rd rr=%rr
+@op_rd_imm6     .... .... .. .. ....        &rd_imm     rd=%rd_c imm=%imm6
+@op_rd_imm8     .... .... .... ....         &rd_imm     rd=%rd_a imm=%imm8
+@fmul           .... .... . ... . ...       &rd_rr      rd=%rd_b rr=%rr_b
+
+#
+# Arithmetic Instructions
+#
+ADD             0000 11 . ..... ....        @op_rd_rr
+ADC             0001 11 . ..... ....        @op_rd_rr
+ADIW            1001 0110 .. .. ....        @op_rd_imm6
+SUB             0001 10 . ..... ....        @op_rd_rr
+SUBI            0101 .... .... ....         @op_rd_imm8
+SBC             0000 10 . ..... ....        @op_rd_rr
+SBCI            0100 .... .... ....         @op_rd_imm8
+SBIW            1001 0111 .. .. ....        @op_rd_imm6
+AND             0010 00 . ..... ....        @op_rd_rr
+ANDI            0111 .... .... ....         @op_rd_imm8
+OR              0010 10 . ..... ....        @op_rd_rr
+ORI             0110 .... .... ....         @op_rd_imm8
+EOR             0010 01 . ..... ....        @op_rd_rr
+COM             1001 010 rd:5 0000
+NEG             1001 010 rd:5 0001
+INC             1001 010 rd:5 0011
+DEC             1001 010 rd:5 1010
+MUL             1001 11 . ..... ....        @op_rd_rr
+MULS            0000 0010 .... ....         &rd_rr      rd=%rd_a rr=%rr_a
+MULSU           0000 0011 0 ... 0 ...       @fmul
+FMUL            0000 0011 0 ... 1 ...       @fmul
+FMULS           0000 0011 1 ... 0 ...       @fmul
+FMULSU          0000 0011 1 ... 1 ...       @fmul
+DES             1001 0100 imm:4 1011
+
+#
+# Branch Instructions
+#
+
+# The 22-bit immediate is partially in the opcode word,
+# and partially in the next.  Use append_16 to build the
+# complete 22-bit value.
+%imm_call       4:5 0:1                     !function=append_16
+
+@op_bit         .... .... . bit:3 ....
+@op_bit_imm     .... .. imm:s7 bit:3
+
+RJMP            1100 imm:s12
+IJMP            1001 0100 0000 1001
+EIJMP           1001 0100 0001 1001
+JMP             1001 010 ..... 110 .        imm=%imm_call
+RCALL           1101 imm:s12
+ICALL           1001 0101 0000 1001
+EICALL          1001 0101 0001 1001
+CALL            1001 010 ..... 111 .        imm=%imm_call
+RET             1001 0101 0000 1000
+RETI            1001 0101 0001 1000
+CPSE            0001 00 . ..... ....        @op_rd_rr
+CP              0001 01 . ..... ....        @op_rd_rr
+CPC             0000 01 . ..... ....        @op_rd_rr
+CPI             0011 .... .... ....         @op_rd_imm8
+SBRC            1111 110 rr:5 0 bit:3
+SBRS            1111 111 rr:5 0 bit:3
+SBIC            1001 1001 reg:5 bit:3
+SBIS            1001 1011 reg:5 bit:3
+BRBS            1111 00 ....... ...         @op_bit_imm
+BRBC            1111 01 ....... ...         @op_bit_imm
+
+#
+# Data Transfer Instructions
+#
+
+%rd_d           4:4                         !function=to_regs_00_30_by_two
+%rr_d           0:4                         !function=to_regs_00_30_by_two
+
+@io_rd_imm      .... . .. ..... ....        &rd_imm     rd=%rd imm=%io_imm
+@ldst_d         .. . . .. . rd:5  . ...     &rd_imm     imm=%ldst_d_imm
+
+# The 16-bit immediate is completely in the next word.
+# Fields cannot be defined with no bits, so we cannot play
+# the same trick and append to a zero-bit value.
+# Defer reading the immediate until trans_{LDS,STS}.
+@ldst_s         .... ... rd:5 ....          imm=0
+
+MOV             0010 11 . ..... ....        @op_rd_rr
+MOVW            0000 0001 .... ....         &rd_rr      rd=%rd_d rr=%rr_d
+LDI             1110 .... .... ....         @op_rd_imm8
+LDS             1001 000 ..... 0000         @ldst_s
+LDX1            1001 000 rd:5 1100
+LDX2            1001 000 rd:5 1101
+LDX3            1001 000 rd:5 1110
+LDY2            1001 000 rd:5 1001
+LDY3            1001 000 rd:5 1010
+LDZ2            1001 000 rd:5 0001
+LDZ3            1001 000 rd:5 0010
+LDDY            10 . 0 .. 0 ..... 1 ...     @ldst_d
+LDDZ            10 . 0 .. 0 ..... 0 ...     @ldst_d
+STS             1001 001 ..... 0000         @ldst_s
+STX1            1001 001 rr:5 1100
+STX2            1001 001 rr:5 1101
+STX3            1001 001 rr:5 1110
+STY2            1001 001 rd:5 1001
+STY3            1001 001 rd:5 1010
+STZ2            1001 001 rd:5 0001
+STZ3            1001 001 rd:5 0010
+STDY            10 . 0 .. 1 ..... 1 ...     @ldst_d
+STDZ            10 . 0 .. 1 ..... 0 ...     @ldst_d
+LPM1            1001 0101 1100 1000
+LPM2            1001 000 rd:5 0100
+LPMX            1001 000 rd:5 0101
+ELPM1           1001 0101 1101 1000
+ELPM2           1001 000 rd:5 0110
+ELPMX           1001 000 rd:5 0111
+SPM             1001 0101 1110 1000
+SPMX            1001 0101 1111 1000
+IN              1011 0 .. ..... ....        @io_rd_imm
+OUT             1011 1 .. ..... ....        @io_rd_imm
+PUSH            1001 001 rd:5 1111
+POP             1001 000 rd:5 1111
+XCH             1001 001 rd:5 0100
+LAC             1001 001 rd:5 0110
+LAS             1001 001 rd:5 0101
+LAT             1001 001 rd:5 0111
+
+#
+# Bit and Bit-test Instructions
+#
+LSR             1001 010 rd:5 0110
+ROR             1001 010 rd:5 0111
+ASR             1001 010 rd:5 0101
+SWAP            1001 010 rd:5 0010
+SBI             1001 1010 reg:5 bit:3
+CBI             1001 1000 reg:5 bit:3
+BST             1111 101 rd:5 0 bit:3
+BLD             1111 100 rd:5 0 bit:3
+BSET            1001 0100 0 bit:3 1000
+BCLR            1001 0100 1 bit:3 1000
+
+#
+# MCU Control Instructions
+#
+BREAK           1001 0101 1001 1000
+NOP             0000 0000 0000 0000
+SLEEP           1001 0101 1000 1000
+WDR             1001 0101 1010 1000
diff --git a/target/avr/machine.c b/target/avr/machine.c
new file mode 100644
index 0000000000..e315442787
--- /dev/null
+++ b/target/avr/machine.c
@@ -0,0 +1,119 @@
+/*
+ * QEMU AVR CPU
+ *
+ * Copyright (c) 2016-2020 Michael Rolnik
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see
+ * <http://www.gnu.org/licenses/lgpl-2.1.html>
+ */
+
+#include "qemu/osdep.h"
+#include "cpu.h"
+#include "migration/cpu.h"
+
+static int get_sreg(QEMUFile *f, void *opaque, size_t size,
+                    const VMStateField *field)
+{
+    CPUAVRState *env = opaque;
+    uint8_t sreg;
+
+    sreg = qemu_get_byte(f);
+    cpu_set_sreg(env, sreg);
+    return 0;
+}
+
+static int put_sreg(QEMUFile *f, void *opaque, size_t size,
+                    const VMStateField *field, QJSON *vmdesc)
+{
+    CPUAVRState *env = opaque;
+    uint8_t sreg = cpu_get_sreg(env);
+
+    qemu_put_byte(f, sreg);
+    return 0;
+}
+
+static const VMStateInfo vms_sreg = {
+    .name = "sreg",
+    .get = get_sreg,
+    .put = put_sreg,
+};
+
+static int get_segment(QEMUFile *f, void *opaque, size_t size,
+                       const VMStateField *field)
+{
+    uint32_t *ramp = opaque;
+    uint8_t temp;
+
+    temp = qemu_get_byte(f);
+    *ramp = ((uint32_t)temp) << 16;
+    return 0;
+}
+
+static int put_segment(QEMUFile *f, void *opaque, size_t size,
+                       const VMStateField *field, QJSON *vmdesc)
+{
+    uint32_t *ramp = opaque;
+    uint8_t temp = *ramp >> 16;
+
+    qemu_put_byte(f, temp);
+    return 0;
+}
+
+static const VMStateInfo vms_rampD = {
+    .name = "rampD",
+    .get = get_segment,
+    .put = put_segment,
+};
+static const VMStateInfo vms_rampX = {
+    .name = "rampX",
+    .get = get_segment,
+    .put = put_segment,
+};
+static const VMStateInfo vms_rampY = {
+    .name = "rampY",
+    .get = get_segment,
+    .put = put_segment,
+};
+static const VMStateInfo vms_rampZ = {
+    .name = "rampZ",
+    .get = get_segment,
+    .put = put_segment,
+};
+static const VMStateInfo vms_eind = {
+    .name = "eind",
+    .get = get_segment,
+    .put = put_segment,
+};
+
+const VMStateDescription vms_avr_cpu = {
+    .name = "cpu",
+    .version_id = 0,
+    .minimum_version_id = 0,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT32(env.pc_w, AVRCPU),
+        VMSTATE_UINT32(env.sp, AVRCPU),
+        VMSTATE_UINT32(env.skip, AVRCPU),
+
+        VMSTATE_UINT32_ARRAY(env.r, AVRCPU, NUMBER_OF_CPU_REGISTERS),
+
+        VMSTATE_SINGLE(env, AVRCPU, 0, vms_sreg, CPUAVRState),
+        VMSTATE_SINGLE(env.rampD, AVRCPU, 0, vms_rampD, uint32_t),
+        VMSTATE_SINGLE(env.rampX, AVRCPU, 0, vms_rampX, uint32_t),
+        VMSTATE_SINGLE(env.rampY, AVRCPU, 0, vms_rampY, uint32_t),
+        VMSTATE_SINGLE(env.rampZ, AVRCPU, 0, vms_rampZ, uint32_t),
+        VMSTATE_SINGLE(env.eind, AVRCPU, 0, vms_eind, uint32_t),
+
+        VMSTATE_END_OF_LIST()
+    }
+};
diff --git a/target/avr/translate.c b/target/avr/translate.c
new file mode 100644
index 0000000000..648dcd5c3e
--- /dev/null
+++ b/target/avr/translate.c
@@ -0,0 +1,3061 @@
+/*
+ * QEMU AVR CPU
+ *
+ * Copyright (c) 2019-2020 Michael Rolnik
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see
+ * <http://www.gnu.org/licenses/lgpl-2.1.html>
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/qemu-print.h"
+#include "tcg/tcg.h"
+#include "cpu.h"
+#include "exec/exec-all.h"
+#include "tcg/tcg-op.h"
+#include "exec/cpu_ldst.h"
+#include "exec/helper-proto.h"
+#include "exec/helper-gen.h"
+#include "exec/log.h"
+#include "exec/translator.h"
+#include "exec/gen-icount.h"
+
+/*
+ *  Define if you want a BREAK instruction translated to a breakpoint
+ *  Active debugging connection is assumed
+ *  This is for
+ *  https://github.com/seharris/qemu-avr-tests/tree/master/instruction-tests
+ *  tests
+ */
+#undef BREAKPOINT_ON_BREAK
+
+static TCGv cpu_pc;
+
+static TCGv cpu_Cf;
+static TCGv cpu_Zf;
+static TCGv cpu_Nf;
+static TCGv cpu_Vf;
+static TCGv cpu_Sf;
+static TCGv cpu_Hf;
+static TCGv cpu_Tf;
+static TCGv cpu_If;
+
+static TCGv cpu_rampD;
+static TCGv cpu_rampX;
+static TCGv cpu_rampY;
+static TCGv cpu_rampZ;
+
+static TCGv cpu_r[NUMBER_OF_CPU_REGISTERS];
+static TCGv cpu_eind;
+static TCGv cpu_sp;
+
+static TCGv cpu_skip;
+
+static const char reg_names[NUMBER_OF_CPU_REGISTERS][8] = {
+    "r0",  "r1",  "r2",  "r3",  "r4",  "r5",  "r6",  "r7",
+    "r8",  "r9",  "r10", "r11", "r12", "r13", "r14", "r15",
+    "r16", "r17", "r18", "r19", "r20", "r21", "r22", "r23",
+    "r24", "r25", "r26", "r27", "r28", "r29", "r30", "r31",
+};
+#define REG(x) (cpu_r[x])
+
+enum {
+    DISAS_EXIT   = DISAS_TARGET_0,  /* We want return to the cpu main loop.  */
+    DISAS_LOOKUP = DISAS_TARGET_1,  /* We have a variable condition exit.  */
+    DISAS_CHAIN  = DISAS_TARGET_2,  /* We have a single condition exit.  */
+};
+
+typedef struct DisasContext DisasContext;
+
+/* This is the state at translation time. */
+struct DisasContext {
+    TranslationBlock *tb;
+
+    CPUAVRState *env;
+    CPUState *cs;
+
+    target_long npc;
+    uint32_t opcode;
+
+    /* Routine used to access memory */
+    int memidx;
+    int bstate;
+    int singlestep;
+
+    /*
+     * some AVR instructions can make the following instruction to be skipped
+     * Let's name those instructions
+     *     A   - instruction that can skip the next one
+     *     B   - instruction that can be skipped. this depends on execution of A
+     * there are two scenarios
+     * 1. A and B belong to the same translation block
+     * 2. A is the last instruction in the translation block and B is the last
+     *
+     * following variables are used to simplify the skipping logic, they are
+     * used in the following manner (sketch)
+     *
+     * TCGLabel *skip_label = NULL;
+     * if (ctx.skip_cond != TCG_COND_NEVER) {
+     *     skip_label = gen_new_label();
+     *     tcg_gen_brcond_tl(skip_cond, skip_var0, skip_var1, skip_label);
+     * }
+     *
+     * if (free_skip_var0) {
+     *     tcg_temp_free(skip_var0);
+     *     free_skip_var0 = false;
+     * }
+     *
+     * translate(&ctx);
+     *
+     * if (skip_label) {
+     *     gen_set_label(skip_label);
+     * }
+     */
+    TCGv skip_var0;
+    TCGv skip_var1;
+    TCGCond skip_cond;
+    bool free_skip_var0;
+};
+
+void avr_cpu_tcg_init(void)
+{
+    int i;
+
+#define AVR_REG_OFFS(x) offsetof(CPUAVRState, x)
+    cpu_pc = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(pc_w), "pc");
+    cpu_Cf = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(sregC), "Cf");
+    cpu_Zf = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(sregZ), "Zf");
+    cpu_Nf = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(sregN), "Nf");
+    cpu_Vf = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(sregV), "Vf");
+    cpu_Sf = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(sregS), "Sf");
+    cpu_Hf = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(sregH), "Hf");
+    cpu_Tf = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(sregT), "Tf");
+    cpu_If = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(sregI), "If");
+    cpu_rampD = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(rampD), "rampD");
+    cpu_rampX = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(rampX), "rampX");
+    cpu_rampY = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(rampY), "rampY");
+    cpu_rampZ = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(rampZ), "rampZ");
+    cpu_eind = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(eind), "eind");
+    cpu_sp = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(sp), "sp");
+    cpu_skip = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(skip), "skip");
+
+    for (i = 0; i < NUMBER_OF_CPU_REGISTERS; i++) {
+        cpu_r[i] = tcg_global_mem_new_i32(cpu_env, AVR_REG_OFFS(r[i]),
+                                          reg_names[i]);
+    }
+#undef AVR_REG_OFFS
+}
+
+static int to_regs_16_31_by_one(DisasContext *ctx, int indx)
+{
+    return 16 + (indx % 16);
+}
+
+static int to_regs_16_23_by_one(DisasContext *ctx, int indx)
+{
+    return 16 + (indx % 8);
+}
+
+static int to_regs_24_30_by_two(DisasContext *ctx, int indx)
+{
+    return 24 + (indx % 4) * 2;
+}
+
+static int to_regs_00_30_by_two(DisasContext *ctx, int indx)
+{
+    return (indx % 16) * 2;
+}
+
+static uint16_t next_word(DisasContext *ctx)
+{
+    return cpu_lduw_code(ctx->env, ctx->npc++ * 2);
+}
+
+static int append_16(DisasContext *ctx, int x)
+{
+    return x << 16 | next_word(ctx);
+}
+
+static bool avr_have_feature(DisasContext *ctx, int feature)
+{
+    if (!avr_feature(ctx->env, feature)) {
+        gen_helper_unsupported(cpu_env);
+        ctx->bstate = DISAS_NORETURN;
+        return false;
+    }
+    return true;
+}
+
+static bool decode_insn(DisasContext *ctx, uint16_t insn);
+#include "decode_insn.inc.c"
+
+/*
+ * Arithmetic Instructions
+ */
+
+/*
+ * Utility functions for updating status registers:
+ *
+ *   - gen_add_CHf()
+ *   - gen_add_Vf()
+ *   - gen_sub_CHf()
+ *   - gen_sub_Vf()
+ *   - gen_NSf()
+ *   - gen_ZNSf()
+ *
+ */
+
+static void gen_add_CHf(TCGv R, TCGv Rd, TCGv Rr)
+{
+    TCGv t1 = tcg_temp_new_i32();
+    TCGv t2 = tcg_temp_new_i32();
+    TCGv t3 = tcg_temp_new_i32();
+
+    tcg_gen_and_tl(t1, Rd, Rr); /* t1 = Rd & Rr */
+    tcg_gen_andc_tl(t2, Rd, R); /* t2 = Rd & ~R */
+    tcg_gen_andc_tl(t3, Rr, R); /* t3 = Rr & ~R */
+    tcg_gen_or_tl(t1, t1, t2); /* t1 = t1 | t2 | t3 */
+    tcg_gen_or_tl(t1, t1, t3);
+
+    tcg_gen_shri_tl(cpu_Cf, t1, 7); /* Cf = t1(7) */
+    tcg_gen_shri_tl(cpu_Hf, t1, 3); /* Hf = t1(3) */
+    tcg_gen_andi_tl(cpu_Hf, cpu_Hf, 1);
+
+    tcg_temp_free_i32(t3);
+    tcg_temp_free_i32(t2);
+    tcg_temp_free_i32(t1);
+}
+
+static void gen_add_Vf(TCGv R, TCGv Rd, TCGv Rr)
+{
+    TCGv t1 = tcg_temp_new_i32();
+    TCGv t2 = tcg_temp_new_i32();
+
+    /* t1 = Rd & Rr & ~R | ~Rd & ~Rr & R */
+    /*    = (Rd ^ R) & ~(Rd ^ Rr) */
+    tcg_gen_xor_tl(t1, Rd, R);
+    tcg_gen_xor_tl(t2, Rd, Rr);
+    tcg_gen_andc_tl(t1, t1, t2);
+
+    tcg_gen_shri_tl(cpu_Vf, t1, 7); /* Vf = t1(7) */
+
+    tcg_temp_free_i32(t2);
+    tcg_temp_free_i32(t1);
+}
+
+static void gen_sub_CHf(TCGv R, TCGv Rd, TCGv Rr)
+{
+    TCGv t1 = tcg_temp_new_i32();
+    TCGv t2 = tcg_temp_new_i32();
+    TCGv t3 = tcg_temp_new_i32();
+
+    tcg_gen_not_tl(t1, Rd); /* t1 = ~Rd */
+    tcg_gen_and_tl(t2, t1, Rr); /* t2 = ~Rd & Rr */
+    tcg_gen_or_tl(t3, t1, Rr); /* t3 = (~Rd | Rr) & R */
+    tcg_gen_and_tl(t3, t3, R);
+    tcg_gen_or_tl(t2, t2, t3); /* t2 = ~Rd & Rr | ~Rd & R | R & Rr */
+
+    tcg_gen_shri_tl(cpu_Cf, t2, 7); /* Cf = t2(7) */
+    tcg_gen_shri_tl(cpu_Hf, t2, 3); /* Hf = t2(3) */
+    tcg_gen_andi_tl(cpu_Hf, cpu_Hf, 1);
+
+    tcg_temp_free_i32(t3);
+    tcg_temp_free_i32(t2);
+    tcg_temp_free_i32(t1);
+}
+
+static void gen_sub_Vf(TCGv R, TCGv Rd, TCGv Rr)
+{
+    TCGv t1 = tcg_temp_new_i32();
+    TCGv t2 = tcg_temp_new_i32();
+
+    /* t1 = Rd & ~Rr & ~R | ~Rd & Rr & R */
+    /*    = (Rd ^ R) & (Rd ^ R) */
+    tcg_gen_xor_tl(t1, Rd, R);
+    tcg_gen_xor_tl(t2, Rd, Rr);
+    tcg_gen_and_tl(t1, t1, t2);
+
+    tcg_gen_shri_tl(cpu_Vf, t1, 7); /* Vf = t1(7) */
+
+    tcg_temp_free_i32(t2);
+    tcg_temp_free_i32(t1);
+}
+
+static void gen_NSf(TCGv R)
+{
+    tcg_gen_shri_tl(cpu_Nf, R, 7); /* Nf = R(7) */
+    tcg_gen_xor_tl(cpu_Sf, cpu_Nf, cpu_Vf); /* Sf = Nf ^ Vf */
+}
+
+static void gen_ZNSf(TCGv R)
+{
+    tcg_gen_setcondi_tl(TCG_COND_EQ, cpu_Zf, R, 0); /* Zf = R == 0 */
+
+    /* update status register */
+    tcg_gen_shri_tl(cpu_Nf, R, 7); /* Nf = R(7) */
+    tcg_gen_xor_tl(cpu_Sf, cpu_Nf, cpu_Vf); /* Sf = Nf ^ Vf */
+}
+
+/*
+ *  Adds two registers without the C Flag and places the result in the
+ *  destination register Rd.
+ */
+static bool trans_ADD(DisasContext *ctx, arg_ADD *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+    TCGv R = tcg_temp_new_i32();
+
+    tcg_gen_add_tl(R, Rd, Rr); /* Rd = Rd + Rr */
+    tcg_gen_andi_tl(R, R, 0xff); /* make it 8 bits */
+
+    /* update status register */
+    gen_add_CHf(R, Rd, Rr);
+    gen_add_Vf(R, Rd, Rr);
+    gen_ZNSf(R);
+
+    /* update output registers */
+    tcg_gen_mov_tl(Rd, R);
+
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  Adds two registers and the contents of the C Flag and places the result in
+ *  the destination register Rd.
+ */
+static bool trans_ADC(DisasContext *ctx, arg_ADC *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+    TCGv R = tcg_temp_new_i32();
+
+    tcg_gen_add_tl(R, Rd, Rr); /* R = Rd + Rr + Cf */
+    tcg_gen_add_tl(R, R, cpu_Cf);
+    tcg_gen_andi_tl(R, R, 0xff); /* make it 8 bits */
+
+    /* update status register */
+    gen_add_CHf(R, Rd, Rr);
+    gen_add_Vf(R, Rd, Rr);
+    gen_ZNSf(R);
+
+    /* update output registers */
+    tcg_gen_mov_tl(Rd, R);
+
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  Adds an immediate value (0 - 63) to a register pair and places the result
+ *  in the register pair. This instruction operates on the upper four register
+ *  pairs, and is well suited for operations on the pointer registers.  This
+ *  instruction is not available in all devices. Refer to the device specific
+ *  instruction set summary.
+ */
+static bool trans_ADIW(DisasContext *ctx, arg_ADIW *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_ADIW_SBIW)) {
+        return true;
+    }
+
+    TCGv RdL = cpu_r[a->rd];
+    TCGv RdH = cpu_r[a->rd + 1];
+    int Imm = (a->imm);
+    TCGv R = tcg_temp_new_i32();
+    TCGv Rd = tcg_temp_new_i32();
+
+    tcg_gen_deposit_tl(Rd, RdL, RdH, 8, 8); /* Rd = RdH:RdL */
+    tcg_gen_addi_tl(R, Rd, Imm); /* R = Rd + Imm */
+    tcg_gen_andi_tl(R, R, 0xffff); /* make it 16 bits */
+
+    /* update status register */
+    tcg_gen_andc_tl(cpu_Cf, Rd, R); /* Cf = Rd & ~R */
+    tcg_gen_shri_tl(cpu_Cf, cpu_Cf, 15);
+    tcg_gen_andc_tl(cpu_Vf, R, Rd); /* Vf = R & ~Rd */
+    tcg_gen_shri_tl(cpu_Vf, cpu_Vf, 15);
+    tcg_gen_setcondi_tl(TCG_COND_EQ, cpu_Zf, R, 0); /* Zf = R == 0 */
+    tcg_gen_shri_tl(cpu_Nf, R, 15); /* Nf = R(15) */
+    tcg_gen_xor_tl(cpu_Sf, cpu_Nf, cpu_Vf);/* Sf = Nf ^ Vf */
+
+    /* update output registers */
+    tcg_gen_andi_tl(RdL, R, 0xff);
+    tcg_gen_shri_tl(RdH, R, 8);
+
+    tcg_temp_free_i32(Rd);
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  Subtracts two registers and places the result in the destination
+ *  register Rd.
+ */
+static bool trans_SUB(DisasContext *ctx, arg_SUB *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+    TCGv R = tcg_temp_new_i32();
+
+    tcg_gen_sub_tl(R, Rd, Rr); /* R = Rd - Rr */
+    tcg_gen_andi_tl(R, R, 0xff); /* make it 8 bits */
+
+    /* update status register */
+    tcg_gen_andc_tl(cpu_Cf, Rd, R); /* Cf = Rd & ~R */
+    gen_sub_CHf(R, Rd, Rr);
+    gen_sub_Vf(R, Rd, Rr);
+    gen_ZNSf(R);
+
+    /* update output registers */
+    tcg_gen_mov_tl(Rd, R);
+
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  Subtracts a register and a constant and places the result in the
+ *  destination register Rd. This instruction is working on Register R16 to R31
+ *  and is very well suited for operations on the X, Y, and Z-pointers.
+ */
+static bool trans_SUBI(DisasContext *ctx, arg_SUBI *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = tcg_const_i32(a->imm);
+    TCGv R = tcg_temp_new_i32();
+
+    tcg_gen_sub_tl(R, Rd, Rr); /* R = Rd - Imm */
+    tcg_gen_andi_tl(R, R, 0xff); /* make it 8 bits */
+
+    /* update status register */
+    gen_sub_CHf(R, Rd, Rr);
+    gen_sub_Vf(R, Rd, Rr);
+    gen_ZNSf(R);
+
+    /* update output registers */
+    tcg_gen_mov_tl(Rd, R);
+
+    tcg_temp_free_i32(R);
+    tcg_temp_free_i32(Rr);
+
+    return true;
+}
+
+/*
+ *  Subtracts two registers and subtracts with the C Flag and places the
+ *  result in the destination register Rd.
+ */
+static bool trans_SBC(DisasContext *ctx, arg_SBC *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+    TCGv R = tcg_temp_new_i32();
+    TCGv zero = tcg_const_i32(0);
+
+    tcg_gen_sub_tl(R, Rd, Rr); /* R = Rd - Rr - Cf */
+    tcg_gen_sub_tl(R, R, cpu_Cf);
+    tcg_gen_andi_tl(R, R, 0xff); /* make it 8 bits */
+
+    /* update status register */
+    gen_sub_CHf(R, Rd, Rr);
+    gen_sub_Vf(R, Rd, Rr);
+    gen_NSf(R);
+
+    /*
+     * Previous value remains unchanged when the result is zero;
+     * cleared otherwise.
+     */
+    tcg_gen_movcond_tl(TCG_COND_EQ, cpu_Zf, R, zero, cpu_Zf, zero);
+
+    /* update output registers */
+    tcg_gen_mov_tl(Rd, R);
+
+    tcg_temp_free_i32(zero);
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  SBCI -- Subtract Immediate with Carry
+ */
+static bool trans_SBCI(DisasContext *ctx, arg_SBCI *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = tcg_const_i32(a->imm);
+    TCGv R = tcg_temp_new_i32();
+    TCGv zero = tcg_const_i32(0);
+
+    tcg_gen_sub_tl(R, Rd, Rr); /* R = Rd - Rr - Cf */
+    tcg_gen_sub_tl(R, R, cpu_Cf);
+    tcg_gen_andi_tl(R, R, 0xff); /* make it 8 bits */
+
+    /* update status register */
+    gen_sub_CHf(R, Rd, Rr);
+    gen_sub_Vf(R, Rd, Rr);
+    gen_NSf(R);
+
+    /*
+     * Previous value remains unchanged when the result is zero;
+     * cleared otherwise.
+     */
+    tcg_gen_movcond_tl(TCG_COND_EQ, cpu_Zf, R, zero, cpu_Zf, zero);
+
+    /* update output registers */
+    tcg_gen_mov_tl(Rd, R);
+
+    tcg_temp_free_i32(zero);
+    tcg_temp_free_i32(R);
+    tcg_temp_free_i32(Rr);
+
+    return true;
+}
+
+/*
+ *  Subtracts an immediate value (0-63) from a register pair and places the
+ *  result in the register pair. This instruction operates on the upper four
+ *  register pairs, and is well suited for operations on the Pointer Registers.
+ *  This instruction is not available in all devices. Refer to the device
+ *  specific instruction set summary.
+ */
+static bool trans_SBIW(DisasContext *ctx, arg_SBIW *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_ADIW_SBIW)) {
+        return true;
+    }
+
+    TCGv RdL = cpu_r[a->rd];
+    TCGv RdH = cpu_r[a->rd + 1];
+    int Imm = (a->imm);
+    TCGv R = tcg_temp_new_i32();
+    TCGv Rd = tcg_temp_new_i32();
+
+    tcg_gen_deposit_tl(Rd, RdL, RdH, 8, 8); /* Rd = RdH:RdL */
+    tcg_gen_subi_tl(R, Rd, Imm); /* R = Rd - Imm */
+    tcg_gen_andi_tl(R, R, 0xffff); /* make it 16 bits */
+
+    /* update status register */
+    tcg_gen_andc_tl(cpu_Cf, R, Rd);
+    tcg_gen_shri_tl(cpu_Cf, cpu_Cf, 15); /* Cf = R & ~Rd */
+    tcg_gen_andc_tl(cpu_Vf, Rd, R);
+    tcg_gen_shri_tl(cpu_Vf, cpu_Vf, 15); /* Vf = Rd & ~R */
+    tcg_gen_setcondi_tl(TCG_COND_EQ, cpu_Zf, R, 0); /* Zf = R == 0 */
+    tcg_gen_shri_tl(cpu_Nf, R, 15); /* Nf = R(15) */
+    tcg_gen_xor_tl(cpu_Sf, cpu_Nf, cpu_Vf); /* Sf = Nf ^ Vf */
+
+    /* update output registers */
+    tcg_gen_andi_tl(RdL, R, 0xff);
+    tcg_gen_shri_tl(RdH, R, 8);
+
+    tcg_temp_free_i32(Rd);
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  Performs the logical AND between the contents of register Rd and register
+ *  Rr and places the result in the destination register Rd.
+ */
+static bool trans_AND(DisasContext *ctx, arg_AND *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+    TCGv R = tcg_temp_new_i32();
+
+    tcg_gen_and_tl(R, Rd, Rr); /* Rd = Rd and Rr */
+
+    /* update status register */
+    tcg_gen_movi_tl(cpu_Vf, 0); /* Vf = 0 */
+    tcg_gen_setcondi_tl(TCG_COND_EQ, cpu_Zf, R, 0); /* Zf = R == 0 */
+    gen_ZNSf(R);
+
+    /* update output registers */
+    tcg_gen_mov_tl(Rd, R);
+
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  Performs the logical AND between the contents of register Rd and a constant
+ *  and places the result in the destination register Rd.
+ */
+static bool trans_ANDI(DisasContext *ctx, arg_ANDI *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    int Imm = (a->imm);
+
+    tcg_gen_andi_tl(Rd, Rd, Imm); /* Rd = Rd & Imm */
+
+    /* update status register */
+    tcg_gen_movi_tl(cpu_Vf, 0x00); /* Vf = 0 */
+    gen_ZNSf(Rd);
+
+    return true;
+}
+
+/*
+ *  Performs the logical OR between the contents of register Rd and register
+ *  Rr and places the result in the destination register Rd.
+ */
+static bool trans_OR(DisasContext *ctx, arg_OR *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+    TCGv R = tcg_temp_new_i32();
+
+    tcg_gen_or_tl(R, Rd, Rr);
+
+    /* update status register */
+    tcg_gen_movi_tl(cpu_Vf, 0);
+    gen_ZNSf(R);
+
+    /* update output registers */
+    tcg_gen_mov_tl(Rd, R);
+
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  Performs the logical OR between the contents of register Rd and a
+ *  constant and places the result in the destination register Rd.
+ */
+static bool trans_ORI(DisasContext *ctx, arg_ORI *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    int Imm = (a->imm);
+
+    tcg_gen_ori_tl(Rd, Rd, Imm); /* Rd = Rd | Imm */
+
+    /* update status register */
+    tcg_gen_movi_tl(cpu_Vf, 0x00); /* Vf = 0 */
+    gen_ZNSf(Rd);
+
+    return true;
+}
+
+/*
+ *  Performs the logical EOR between the contents of register Rd and
+ *  register Rr and places the result in the destination register Rd.
+ */
+static bool trans_EOR(DisasContext *ctx, arg_EOR *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+
+    tcg_gen_xor_tl(Rd, Rd, Rr);
+
+    /* update status register */
+    tcg_gen_movi_tl(cpu_Vf, 0);
+    gen_ZNSf(Rd);
+
+    return true;
+}
+
+/*
+ *  Clears the specified bits in register Rd. Performs the logical AND
+ *  between the contents of register Rd and the complement of the constant mask
+ *  K. The result will be placed in register Rd.
+ */
+static bool trans_COM(DisasContext *ctx, arg_COM *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv R = tcg_temp_new_i32();
+
+    tcg_gen_xori_tl(Rd, Rd, 0xff);
+
+    /* update status register */
+    tcg_gen_movi_tl(cpu_Cf, 1); /* Cf = 1 */
+    tcg_gen_movi_tl(cpu_Vf, 0); /* Vf = 0 */
+    gen_ZNSf(Rd);
+
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  Replaces the contents of register Rd with its two's complement; the
+ *  value $80 is left unchanged.
+ */
+static bool trans_NEG(DisasContext *ctx, arg_NEG *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv t0 = tcg_const_i32(0);
+    TCGv R = tcg_temp_new_i32();
+
+    tcg_gen_sub_tl(R, t0, Rd); /* R = 0 - Rd */
+    tcg_gen_andi_tl(R, R, 0xff); /* make it 8 bits */
+
+    /* update status register */
+    gen_sub_CHf(R, t0, Rd);
+    gen_sub_Vf(R, t0, Rd);
+    gen_ZNSf(R);
+
+    /* update output registers */
+    tcg_gen_mov_tl(Rd, R);
+
+    tcg_temp_free_i32(t0);
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  Adds one -1- to the contents of register Rd and places the result in the
+ *  destination register Rd.  The C Flag in SREG is not affected by the
+ *  operation, thus allowing the INC instruction to be used on a loop counter in
+ *  multiple-precision computations.  When operating on unsigned numbers, only
+ *  BREQ and BRNE branches can be expected to perform consistently. When
+ *  operating on two's complement values, all signed branches are available.
+ */
+static bool trans_INC(DisasContext *ctx, arg_INC *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+
+    tcg_gen_addi_tl(Rd, Rd, 1);
+    tcg_gen_andi_tl(Rd, Rd, 0xff);
+
+    /* update status register */
+    tcg_gen_setcondi_tl(TCG_COND_EQ, cpu_Vf, Rd, 0x80); /* Vf = Rd == 0x80 */
+    gen_ZNSf(Rd);
+
+    return true;
+}
+
+/*
+ *  Subtracts one -1- from the contents of register Rd and places the result
+ *  in the destination register Rd.  The C Flag in SREG is not affected by the
+ *  operation, thus allowing the DEC instruction to be used on a loop counter in
+ *  multiple-precision computations.  When operating on unsigned values, only
+ *  BREQ and BRNE branches can be expected to perform consistently.  When
+ *  operating on two's complement values, all signed branches are available.
+ */
+static bool trans_DEC(DisasContext *ctx, arg_DEC *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+
+    tcg_gen_subi_tl(Rd, Rd, 1); /* Rd = Rd - 1 */
+    tcg_gen_andi_tl(Rd, Rd, 0xff); /* make it 8 bits */
+
+    /* update status register */
+    tcg_gen_setcondi_tl(TCG_COND_EQ, cpu_Vf, Rd, 0x7f); /* Vf = Rd == 0x7f */
+    gen_ZNSf(Rd);
+
+    return true;
+}
+
+/*
+ *  This instruction performs 8-bit x 8-bit -> 16-bit unsigned multiplication.
+ */
+static bool trans_MUL(DisasContext *ctx, arg_MUL *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_MUL)) {
+        return true;
+    }
+
+    TCGv R0 = cpu_r[0];
+    TCGv R1 = cpu_r[1];
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+    TCGv R = tcg_temp_new_i32();
+
+    tcg_gen_mul_tl(R, Rd, Rr); /* R = Rd * Rr */
+    tcg_gen_andi_tl(R0, R, 0xff);
+    tcg_gen_shri_tl(R1, R, 8);
+
+    /* update status register */
+    tcg_gen_shri_tl(cpu_Cf, R, 15); /* Cf = R(15) */
+    tcg_gen_setcondi_tl(TCG_COND_EQ, cpu_Zf, R, 0); /* Zf = R == 0 */
+
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  This instruction performs 8-bit x 8-bit -> 16-bit signed multiplication.
+ */
+static bool trans_MULS(DisasContext *ctx, arg_MULS *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_MUL)) {
+        return true;
+    }
+
+    TCGv R0 = cpu_r[0];
+    TCGv R1 = cpu_r[1];
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+    TCGv R = tcg_temp_new_i32();
+    TCGv t0 = tcg_temp_new_i32();
+    TCGv t1 = tcg_temp_new_i32();
+
+    tcg_gen_ext8s_tl(t0, Rd); /* make Rd full 32 bit signed */
+    tcg_gen_ext8s_tl(t1, Rr); /* make Rr full 32 bit signed */
+    tcg_gen_mul_tl(R, t0, t1); /* R = Rd * Rr */
+    tcg_gen_andi_tl(R, R, 0xffff); /* make it 16 bits */
+    tcg_gen_andi_tl(R0, R, 0xff);
+    tcg_gen_shri_tl(R1, R, 8);
+
+    /* update status register */
+    tcg_gen_shri_tl(cpu_Cf, R, 15); /* Cf = R(15) */
+    tcg_gen_setcondi_tl(TCG_COND_EQ, cpu_Zf, R, 0); /* Zf = R == 0 */
+
+    tcg_temp_free_i32(t1);
+    tcg_temp_free_i32(t0);
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  This instruction performs 8-bit x 8-bit -> 16-bit multiplication of a
+ *  signed and an unsigned number.
+ */
+static bool trans_MULSU(DisasContext *ctx, arg_MULSU *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_MUL)) {
+        return true;
+    }
+
+    TCGv R0 = cpu_r[0];
+    TCGv R1 = cpu_r[1];
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+    TCGv R = tcg_temp_new_i32();
+    TCGv t0 = tcg_temp_new_i32();
+
+    tcg_gen_ext8s_tl(t0, Rd); /* make Rd full 32 bit signed */
+    tcg_gen_mul_tl(R, t0, Rr); /* R = Rd * Rr */
+    tcg_gen_andi_tl(R, R, 0xffff); /* make R 16 bits */
+    tcg_gen_andi_tl(R0, R, 0xff);
+    tcg_gen_shri_tl(R1, R, 8);
+
+    /* update status register */
+    tcg_gen_shri_tl(cpu_Cf, R, 15); /* Cf = R(15) */
+    tcg_gen_setcondi_tl(TCG_COND_EQ, cpu_Zf, R, 0); /* Zf = R == 0 */
+
+    tcg_temp_free_i32(t0);
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  This instruction performs 8-bit x 8-bit -> 16-bit unsigned
+ *  multiplication and shifts the result one bit left.
+ */
+static bool trans_FMUL(DisasContext *ctx, arg_FMUL *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_MUL)) {
+        return true;
+    }
+
+    TCGv R0 = cpu_r[0];
+    TCGv R1 = cpu_r[1];
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+    TCGv R = tcg_temp_new_i32();
+
+    tcg_gen_mul_tl(R, Rd, Rr); /* R = Rd * Rr */
+
+    /* update status register */
+    tcg_gen_shri_tl(cpu_Cf, R, 15); /* Cf = R(15) */
+    tcg_gen_setcondi_tl(TCG_COND_EQ, cpu_Zf, R, 0); /* Zf = R == 0 */
+
+    /* update output registers */
+    tcg_gen_shli_tl(R, R, 1);
+    tcg_gen_andi_tl(R0, R, 0xff);
+    tcg_gen_shri_tl(R1, R, 8);
+    tcg_gen_andi_tl(R1, R1, 0xff);
+
+
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  This instruction performs 8-bit x 8-bit -> 16-bit signed multiplication
+ *  and shifts the result one bit left.
+ */
+static bool trans_FMULS(DisasContext *ctx, arg_FMULS *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_MUL)) {
+        return true;
+    }
+
+    TCGv R0 = cpu_r[0];
+    TCGv R1 = cpu_r[1];
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+    TCGv R = tcg_temp_new_i32();
+    TCGv t0 = tcg_temp_new_i32();
+    TCGv t1 = tcg_temp_new_i32();
+
+    tcg_gen_ext8s_tl(t0, Rd); /* make Rd full 32 bit signed */
+    tcg_gen_ext8s_tl(t1, Rr); /* make Rr full 32 bit signed */
+    tcg_gen_mul_tl(R, t0, t1); /* R = Rd * Rr */
+    tcg_gen_andi_tl(R, R, 0xffff); /* make it 16 bits */
+
+    /* update status register */
+    tcg_gen_shri_tl(cpu_Cf, R, 15); /* Cf = R(15) */
+    tcg_gen_setcondi_tl(TCG_COND_EQ, cpu_Zf, R, 0); /* Zf = R == 0 */
+
+    /* update output registers */
+    tcg_gen_shli_tl(R, R, 1);
+    tcg_gen_andi_tl(R0, R, 0xff);
+    tcg_gen_shri_tl(R1, R, 8);
+    tcg_gen_andi_tl(R1, R1, 0xff);
+
+    tcg_temp_free_i32(t1);
+    tcg_temp_free_i32(t0);
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  This instruction performs 8-bit x 8-bit -> 16-bit signed multiplication
+ *  and shifts the result one bit left.
+ */
+static bool trans_FMULSU(DisasContext *ctx, arg_FMULSU *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_MUL)) {
+        return true;
+    }
+
+    TCGv R0 = cpu_r[0];
+    TCGv R1 = cpu_r[1];
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+    TCGv R = tcg_temp_new_i32();
+    TCGv t0 = tcg_temp_new_i32();
+
+    tcg_gen_ext8s_tl(t0, Rd); /* make Rd full 32 bit signed */
+    tcg_gen_mul_tl(R, t0, Rr); /* R = Rd * Rr */
+    tcg_gen_andi_tl(R, R, 0xffff); /* make it 16 bits */
+
+    /* update status register */
+    tcg_gen_shri_tl(cpu_Cf, R, 15); /* Cf = R(15) */
+    tcg_gen_setcondi_tl(TCG_COND_EQ, cpu_Zf, R, 0); /* Zf = R == 0 */
+
+    /* update output registers */
+    tcg_gen_shli_tl(R, R, 1);
+    tcg_gen_andi_tl(R0, R, 0xff);
+    tcg_gen_shri_tl(R1, R, 8);
+    tcg_gen_andi_tl(R1, R1, 0xff);
+
+    tcg_temp_free_i32(t0);
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  The module is an instruction set extension to the AVR CPU, performing
+ *  DES iterations. The 64-bit data block (plaintext or ciphertext) is placed in
+ *  the CPU register file, registers R0-R7, where LSB of data is placed in LSB
+ *  of R0 and MSB of data is placed in MSB of R7. The full 64-bit key (including
+ *  parity bits) is placed in registers R8- R15, organized in the register file
+ *  with LSB of key in LSB of R8 and MSB of key in MSB of R15. Executing one DES
+ *  instruction performs one round in the DES algorithm. Sixteen rounds must be
+ *  executed in increasing order to form the correct DES ciphertext or
+ *  plaintext. Intermediate results are stored in the register file (R0-R15)
+ *  after each DES instruction. The instruction's operand (K) determines which
+ *  round is executed, and the half carry flag (H) determines whether encryption
+ *  or decryption is performed.  The DES algorithm is described in
+ *  "Specifications for the Data Encryption Standard" (Federal Information
+ *  Processing Standards Publication 46). Intermediate results in this
+ *  implementation differ from the standard because the initial permutation and
+ *  the inverse initial permutation are performed each iteration. This does not
+ *  affect the result in the final ciphertext or plaintext, but reduces
+ *  execution time.
+ */
+static bool trans_DES(DisasContext *ctx, arg_DES *a)
+{
+    /* TODO */
+    if (!avr_have_feature(ctx, AVR_FEATURE_DES)) {
+        return true;
+    }
+
+    qemu_log_mask(LOG_UNIMP, "%s: not implemented\n", __func__);
+
+    return true;
+}
+
+/*
+ * Branch Instructions
+ */
+static void gen_jmp_ez(DisasContext *ctx)
+{
+    tcg_gen_deposit_tl(cpu_pc, cpu_r[30], cpu_r[31], 8, 8);
+    tcg_gen_or_tl(cpu_pc, cpu_pc, cpu_eind);
+    ctx->bstate = DISAS_LOOKUP;
+}
+
+static void gen_jmp_z(DisasContext *ctx)
+{
+    tcg_gen_deposit_tl(cpu_pc, cpu_r[30], cpu_r[31], 8, 8);
+    ctx->bstate = DISAS_LOOKUP;
+}
+
+static void gen_push_ret(DisasContext *ctx, int ret)
+{
+    if (avr_feature(ctx->env, AVR_FEATURE_1_BYTE_PC)) {
+
+        TCGv t0 = tcg_const_i32((ret & 0x0000ff));
+
+        tcg_gen_qemu_st_tl(t0, cpu_sp, MMU_DATA_IDX, MO_UB);
+        tcg_gen_subi_tl(cpu_sp, cpu_sp, 1);
+
+        tcg_temp_free_i32(t0);
+    } else if (avr_feature(ctx->env, AVR_FEATURE_2_BYTE_PC)) {
+
+        TCGv t0 = tcg_const_i32((ret & 0x00ffff));
+
+        tcg_gen_subi_tl(cpu_sp, cpu_sp, 1);
+        tcg_gen_qemu_st_tl(t0, cpu_sp, MMU_DATA_IDX, MO_BEUW);
+        tcg_gen_subi_tl(cpu_sp, cpu_sp, 1);
+
+        tcg_temp_free_i32(t0);
+
+    } else if (avr_feature(ctx->env, AVR_FEATURE_3_BYTE_PC)) {
+
+        TCGv lo = tcg_const_i32((ret & 0x0000ff));
+        TCGv hi = tcg_const_i32((ret & 0xffff00) >> 8);
+
+        tcg_gen_qemu_st_tl(lo, cpu_sp, MMU_DATA_IDX, MO_UB);
+        tcg_gen_subi_tl(cpu_sp, cpu_sp, 2);
+        tcg_gen_qemu_st_tl(hi, cpu_sp, MMU_DATA_IDX, MO_BEUW);
+        tcg_gen_subi_tl(cpu_sp, cpu_sp, 1);
+
+        tcg_temp_free_i32(lo);
+        tcg_temp_free_i32(hi);
+    }
+}
+
+static void gen_pop_ret(DisasContext *ctx, TCGv ret)
+{
+    if (avr_feature(ctx->env, AVR_FEATURE_1_BYTE_PC)) {
+        tcg_gen_addi_tl(cpu_sp, cpu_sp, 1);
+        tcg_gen_qemu_ld_tl(ret, cpu_sp, MMU_DATA_IDX, MO_UB);
+    } else if (avr_feature(ctx->env, AVR_FEATURE_2_BYTE_PC)) {
+        tcg_gen_addi_tl(cpu_sp, cpu_sp, 1);
+        tcg_gen_qemu_ld_tl(ret, cpu_sp, MMU_DATA_IDX, MO_BEUW);
+        tcg_gen_addi_tl(cpu_sp, cpu_sp, 1);
+    } else if (avr_feature(ctx->env, AVR_FEATURE_3_BYTE_PC)) {
+        TCGv lo = tcg_temp_new_i32();
+        TCGv hi = tcg_temp_new_i32();
+
+        tcg_gen_addi_tl(cpu_sp, cpu_sp, 1);
+        tcg_gen_qemu_ld_tl(hi, cpu_sp, MMU_DATA_IDX, MO_BEUW);
+
+        tcg_gen_addi_tl(cpu_sp, cpu_sp, 2);
+        tcg_gen_qemu_ld_tl(lo, cpu_sp, MMU_DATA_IDX, MO_UB);
+
+        tcg_gen_deposit_tl(ret, lo, hi, 8, 16);
+
+        tcg_temp_free_i32(lo);
+        tcg_temp_free_i32(hi);
+    }
+}
+
+static void gen_goto_tb(DisasContext *ctx, int n, target_ulong dest)
+{
+    TranslationBlock *tb = ctx->tb;
+
+    if (ctx->singlestep == 0) {
+        tcg_gen_goto_tb(n);
+        tcg_gen_movi_i32(cpu_pc, dest);
+        tcg_gen_exit_tb(tb, n);
+    } else {
+        tcg_gen_movi_i32(cpu_pc, dest);
+        gen_helper_debug(cpu_env);
+        tcg_gen_exit_tb(NULL, 0);
+    }
+    ctx->bstate = DISAS_NORETURN;
+}
+
+/*
+ *  Relative jump to an address within PC - 2K +1 and PC + 2K (words). For
+ *  AVR microcontrollers with Program memory not exceeding 4K words (8KB) this
+ *  instruction can address the entire memory from every address location. See
+ *  also JMP.
+ */
+static bool trans_RJMP(DisasContext *ctx, arg_RJMP *a)
+{
+    int dst = ctx->npc + a->imm;
+
+    gen_goto_tb(ctx, 0, dst);
+
+    return true;
+}
+
+/*
+ *  Indirect jump to the address pointed to by the Z (16 bits) Pointer
+ *  Register in the Register File. The Z-pointer Register is 16 bits wide and
+ *  allows jump within the lowest 64K words (128KB) section of Program memory.
+ *  This instruction is not available in all devices. Refer to the device
+ *  specific instruction set summary.
+ */
+static bool trans_IJMP(DisasContext *ctx, arg_IJMP *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_IJMP_ICALL)) {
+        return true;
+    }
+
+    gen_jmp_z(ctx);
+
+    return true;
+}
+
+/*
+ *  Indirect jump to the address pointed to by the Z (16 bits) Pointer
+ *  Register in the Register File and the EIND Register in the I/O space. This
+ *  instruction allows for indirect jumps to the entire 4M (words) Program
+ *  memory space. See also IJMP.  This instruction is not available in all
+ *  devices. Refer to the device specific instruction set summary.
+ */
+static bool trans_EIJMP(DisasContext *ctx, arg_EIJMP *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_EIJMP_EICALL)) {
+        return true;
+    }
+
+    gen_jmp_ez(ctx);
+    return true;
+}
+
+/*
+ *  Jump to an address within the entire 4M (words) Program memory. See also
+ *  RJMP.  This instruction is not available in all devices. Refer to the device
+ *  specific instruction set summary.0
+ */
+static bool trans_JMP(DisasContext *ctx, arg_JMP *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_JMP_CALL)) {
+        return true;
+    }
+
+    gen_goto_tb(ctx, 0, a->imm);
+
+    return true;
+}
+
+/*
+ *  Relative call to an address within PC - 2K + 1 and PC + 2K (words). The
+ *  return address (the instruction after the RCALL) is stored onto the Stack.
+ *  See also CALL. For AVR microcontrollers with Program memory not exceeding 4K
+ *  words (8KB) this instruction can address the entire memory from every
+ *  address location. The Stack Pointer uses a post-decrement scheme during
+ *  RCALL.
+ */
+static bool trans_RCALL(DisasContext *ctx, arg_RCALL *a)
+{
+    int ret = ctx->npc;
+    int dst = ctx->npc + a->imm;
+
+    gen_push_ret(ctx, ret);
+    gen_goto_tb(ctx, 0, dst);
+
+    return true;
+}
+
+/*
+ *  Calls to a subroutine within the entire 4M (words) Program memory. The
+ *  return address (to the instruction after the CALL) will be stored onto the
+ *  Stack. See also RCALL. The Stack Pointer uses a post-decrement scheme during
+ *  CALL.  This instruction is not available in all devices. Refer to the device
+ *  specific instruction set summary.
+ */
+static bool trans_ICALL(DisasContext *ctx, arg_ICALL *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_IJMP_ICALL)) {
+        return true;
+    }
+
+    int ret = ctx->npc;
+
+    gen_push_ret(ctx, ret);
+    gen_jmp_z(ctx);
+
+    return true;
+}
+
+/*
+ *  Indirect call of a subroutine pointed to by the Z (16 bits) Pointer
+ *  Register in the Register File and the EIND Register in the I/O space. This
+ *  instruction allows for indirect calls to the entire 4M (words) Program
+ *  memory space. See also ICALL. The Stack Pointer uses a post-decrement scheme
+ *  during EICALL.  This instruction is not available in all devices. Refer to
+ *  the device specific instruction set summary.
+ */
+static bool trans_EICALL(DisasContext *ctx, arg_EICALL *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_EIJMP_EICALL)) {
+        return true;
+    }
+
+    int ret = ctx->npc;
+
+    gen_push_ret(ctx, ret);
+    gen_jmp_ez(ctx);
+    return true;
+}
+
+/*
+ *  Calls to a subroutine within the entire Program memory. The return
+ *  address (to the instruction after the CALL) will be stored onto the Stack.
+ *  (See also RCALL). The Stack Pointer uses a post-decrement scheme during
+ *  CALL.  This instruction is not available in all devices. Refer to the device
+ *  specific instruction set summary.
+ */
+static bool trans_CALL(DisasContext *ctx, arg_CALL *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_JMP_CALL)) {
+        return true;
+    }
+
+    int Imm = a->imm;
+    int ret = ctx->npc;
+
+    gen_push_ret(ctx, ret);
+    gen_goto_tb(ctx, 0, Imm);
+
+    return true;
+}
+
+/*
+ *  Returns from subroutine. The return address is loaded from the STACK.
+ *  The Stack Pointer uses a preincrement scheme during RET.
+ */
+static bool trans_RET(DisasContext *ctx, arg_RET *a)
+{
+    gen_pop_ret(ctx, cpu_pc);
+
+    ctx->bstate = DISAS_LOOKUP;
+    return true;
+}
+
+/*
+ *  Returns from interrupt. The return address is loaded from the STACK and
+ *  the Global Interrupt Flag is set.  Note that the Status Register is not
+ *  automatically stored when entering an interrupt routine, and it is not
+ *  restored when returning from an interrupt routine. This must be handled by
+ *  the application program. The Stack Pointer uses a pre-increment scheme
+ *  during RETI.
+ */
+static bool trans_RETI(DisasContext *ctx, arg_RETI *a)
+{
+    gen_pop_ret(ctx, cpu_pc);
+    tcg_gen_movi_tl(cpu_If, 1);
+
+    /* Need to return to main loop to re-evaluate interrupts.  */
+    ctx->bstate = DISAS_EXIT;
+    return true;
+}
+
+/*
+ *  This instruction performs a compare between two registers Rd and Rr, and
+ *  skips the next instruction if Rd = Rr.
+ */
+static bool trans_CPSE(DisasContext *ctx, arg_CPSE *a)
+{
+    ctx->skip_cond = TCG_COND_EQ;
+    ctx->skip_var0 = cpu_r[a->rd];
+    ctx->skip_var1 = cpu_r[a->rr];
+    return true;
+}
+
+/*
+ *  This instruction performs a compare between two registers Rd and Rr.
+ *  None of the registers are changed. All conditional branches can be used
+ *  after this instruction.
+ */
+static bool trans_CP(DisasContext *ctx, arg_CP *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+    TCGv R = tcg_temp_new_i32();
+
+    tcg_gen_sub_tl(R, Rd, Rr); /* R = Rd - Rr */
+    tcg_gen_andi_tl(R, R, 0xff); /* make it 8 bits */
+
+    /* update status register */
+    gen_sub_CHf(R, Rd, Rr);
+    gen_sub_Vf(R, Rd, Rr);
+    gen_ZNSf(R);
+
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  This instruction performs a compare between two registers Rd and Rr and
+ *  also takes into account the previous carry. None of the registers are
+ *  changed. All conditional branches can be used after this instruction.
+ */
+static bool trans_CPC(DisasContext *ctx, arg_CPC *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+    TCGv R = tcg_temp_new_i32();
+    TCGv zero = tcg_const_i32(0);
+
+    tcg_gen_sub_tl(R, Rd, Rr); /* R = Rd - Rr - Cf */
+    tcg_gen_sub_tl(R, R, cpu_Cf);
+    tcg_gen_andi_tl(R, R, 0xff); /* make it 8 bits */
+    /* update status register */
+    gen_sub_CHf(R, Rd, Rr);
+    gen_sub_Vf(R, Rd, Rr);
+    gen_NSf(R);
+
+    /*
+     * Previous value remains unchanged when the result is zero;
+     * cleared otherwise.
+     */
+    tcg_gen_movcond_tl(TCG_COND_EQ, cpu_Zf, R, zero, cpu_Zf, zero);
+
+    tcg_temp_free_i32(zero);
+    tcg_temp_free_i32(R);
+
+    return true;
+}
+
+/*
+ *  This instruction performs a compare between register Rd and a constant.
+ *  The register is not changed. All conditional branches can be used after this
+ *  instruction.
+ */
+static bool trans_CPI(DisasContext *ctx, arg_CPI *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    int Imm = a->imm;
+    TCGv Rr = tcg_const_i32(Imm);
+    TCGv R = tcg_temp_new_i32();
+
+    tcg_gen_sub_tl(R, Rd, Rr); /* R = Rd - Rr */
+    tcg_gen_andi_tl(R, R, 0xff); /* make it 8 bits */
+
+    /* update status register */
+    gen_sub_CHf(R, Rd, Rr);
+    gen_sub_Vf(R, Rd, Rr);
+    gen_ZNSf(R);
+
+    tcg_temp_free_i32(R);
+    tcg_temp_free_i32(Rr);
+
+    return true;
+}
+
+/*
+ *  This instruction tests a single bit in a register and skips the next
+ *  instruction if the bit is cleared.
+ */
+static bool trans_SBRC(DisasContext *ctx, arg_SBRC *a)
+{
+    TCGv Rr = cpu_r[a->rr];
+
+    ctx->skip_cond = TCG_COND_EQ;
+    ctx->skip_var0 = tcg_temp_new();
+    ctx->free_skip_var0 = true;
+
+    tcg_gen_andi_tl(ctx->skip_var0, Rr, 1 << a->bit);
+    return true;
+}
+
+/*
+ *  This instruction tests a single bit in a register and skips the next
+ *  instruction if the bit is set.
+ */
+static bool trans_SBRS(DisasContext *ctx, arg_SBRS *a)
+{
+    TCGv Rr = cpu_r[a->rr];
+
+    ctx->skip_cond = TCG_COND_NE;
+    ctx->skip_var0 = tcg_temp_new();
+    ctx->free_skip_var0 = true;
+
+    tcg_gen_andi_tl(ctx->skip_var0, Rr, 1 << a->bit);
+    return true;
+}
+
+/*
+ *  This instruction tests a single bit in an I/O Register and skips the
+ *  next instruction if the bit is cleared. This instruction operates on the
+ *  lower 32 I/O Registers -- addresses 0-31.
+ */
+static bool trans_SBIC(DisasContext *ctx, arg_SBIC *a)
+{
+    TCGv temp = tcg_const_i32(a->reg);
+
+    gen_helper_inb(temp, cpu_env, temp);
+    tcg_gen_andi_tl(temp, temp, 1 << a->bit);
+    ctx->skip_cond = TCG_COND_EQ;
+    ctx->skip_var0 = temp;
+    ctx->free_skip_var0 = true;
+
+    return true;
+}
+
+/*
+ *  This instruction tests a single bit in an I/O Register and skips the
+ *  next instruction if the bit is set. This instruction operates on the lower
+ *  32 I/O Registers -- addresses 0-31.
+ */
+static bool trans_SBIS(DisasContext *ctx, arg_SBIS *a)
+{
+    TCGv temp = tcg_const_i32(a->reg);
+
+    gen_helper_inb(temp, cpu_env, temp);
+    tcg_gen_andi_tl(temp, temp, 1 << a->bit);
+    ctx->skip_cond = TCG_COND_NE;
+    ctx->skip_var0 = temp;
+    ctx->free_skip_var0 = true;
+
+    return true;
+}
+
+/*
+ *  Conditional relative branch. Tests a single bit in SREG and branches
+ *  relatively to PC if the bit is cleared. This instruction branches relatively
+ *  to PC in either direction (PC - 63 < = destination <= PC + 64). The
+ *  parameter k is the offset from PC and is represented in two's complement
+ *  form.
+ */
+static bool trans_BRBC(DisasContext *ctx, arg_BRBC *a)
+{
+    TCGLabel *not_taken = gen_new_label();
+
+    TCGv var;
+
+    switch (a->bit) {
+    case 0x00:
+        var = cpu_Cf;
+        break;
+    case 0x01:
+        var = cpu_Zf;
+        break;
+    case 0x02:
+        var = cpu_Nf;
+        break;
+    case 0x03:
+        var = cpu_Vf;
+        break;
+    case 0x04:
+        var = cpu_Sf;
+        break;
+    case 0x05:
+        var = cpu_Hf;
+        break;
+    case 0x06:
+        var = cpu_Tf;
+        break;
+    case 0x07:
+        var = cpu_If;
+        break;
+    default:
+        g_assert_not_reached();
+    }
+
+    tcg_gen_brcondi_i32(TCG_COND_NE, var, 0, not_taken);
+    gen_goto_tb(ctx, 0, ctx->npc + a->imm);
+    gen_set_label(not_taken);
+
+    ctx->bstate = DISAS_CHAIN;
+    return true;
+}
+
+/*
+ *  Conditional relative branch. Tests a single bit in SREG and branches
+ *  relatively to PC if the bit is set. This instruction branches relatively to
+ *  PC in either direction (PC - 63 < = destination <= PC + 64). The parameter k
+ *  is the offset from PC and is represented in two's complement form.
+ */
+static bool trans_BRBS(DisasContext *ctx, arg_BRBS *a)
+{
+    TCGLabel *not_taken = gen_new_label();
+
+    TCGv var;
+
+    switch (a->bit) {
+    case 0x00:
+        var = cpu_Cf;
+        break;
+    case 0x01:
+        var = cpu_Zf;
+        break;
+    case 0x02:
+        var = cpu_Nf;
+        break;
+    case 0x03:
+        var = cpu_Vf;
+        break;
+    case 0x04:
+        var = cpu_Sf;
+        break;
+    case 0x05:
+        var = cpu_Hf;
+        break;
+    case 0x06:
+        var = cpu_Tf;
+        break;
+    case 0x07:
+        var = cpu_If;
+        break;
+    default:
+        g_assert_not_reached();
+    }
+
+    tcg_gen_brcondi_i32(TCG_COND_EQ, var, 0, not_taken);
+    gen_goto_tb(ctx, 0, ctx->npc + a->imm);
+    gen_set_label(not_taken);
+
+    ctx->bstate = DISAS_CHAIN;
+    return true;
+}
+
+/*
+ * Data Transfer Instructions
+ */
+
+/*
+ *  in the gen_set_addr & gen_get_addr functions
+ *  H assumed to be in 0x00ff0000 format
+ *  M assumed to be in 0x000000ff format
+ *  L assumed to be in 0x000000ff format
+ */
+static void gen_set_addr(TCGv addr, TCGv H, TCGv M, TCGv L)
+{
+
+    tcg_gen_andi_tl(L, addr, 0x000000ff);
+
+    tcg_gen_andi_tl(M, addr, 0x0000ff00);
+    tcg_gen_shri_tl(M, M, 8);
+
+    tcg_gen_andi_tl(H, addr, 0x00ff0000);
+}
+
+static void gen_set_xaddr(TCGv addr)
+{
+    gen_set_addr(addr, cpu_rampX, cpu_r[27], cpu_r[26]);
+}
+
+static void gen_set_yaddr(TCGv addr)
+{
+    gen_set_addr(addr, cpu_rampY, cpu_r[29], cpu_r[28]);
+}
+
+static void gen_set_zaddr(TCGv addr)
+{
+    gen_set_addr(addr, cpu_rampZ, cpu_r[31], cpu_r[30]);
+}
+
+static TCGv gen_get_addr(TCGv H, TCGv M, TCGv L)
+{
+    TCGv addr = tcg_temp_new_i32();
+
+    tcg_gen_deposit_tl(addr, M, H, 8, 8);
+    tcg_gen_deposit_tl(addr, L, addr, 8, 16);
+
+    return addr;
+}
+
+static TCGv gen_get_xaddr(void)
+{
+    return gen_get_addr(cpu_rampX, cpu_r[27], cpu_r[26]);
+}
+
+static TCGv gen_get_yaddr(void)
+{
+    return gen_get_addr(cpu_rampY, cpu_r[29], cpu_r[28]);
+}
+
+static TCGv gen_get_zaddr(void)
+{
+    return gen_get_addr(cpu_rampZ, cpu_r[31], cpu_r[30]);
+}
+
+/*
+ *  Load one byte indirect from data space to register and stores an clear
+ *  the bits in data space specified by the register. The instruction can only
+ *  be used towards internal SRAM.  The data location is pointed to by the Z (16
+ *  bits) Pointer Register in the Register File. Memory access is limited to the
+ *  current data segment of 64KB. To access another data segment in devices with
+ *  more than 64KB data space, the RAMPZ in register in the I/O area has to be
+ *  changed.  The Z-pointer Register is left unchanged by the operation. This
+ *  instruction is especially suited for clearing status bits stored in SRAM.
+ */
+static void gen_data_store(DisasContext *ctx, TCGv data, TCGv addr)
+{
+    if (ctx->tb->flags & TB_FLAGS_FULL_ACCESS) {
+        gen_helper_fullwr(cpu_env, data, addr);
+    } else {
+        tcg_gen_qemu_st8(data, addr, MMU_DATA_IDX); /* mem[addr] = data */
+    }
+}
+
+static void gen_data_load(DisasContext *ctx, TCGv data, TCGv addr)
+{
+    if (ctx->tb->flags & TB_FLAGS_FULL_ACCESS) {
+        gen_helper_fullrd(data, cpu_env, addr);
+    } else {
+        tcg_gen_qemu_ld8u(data, addr, MMU_DATA_IDX); /* data = mem[addr] */
+    }
+}
+
+/*
+ *  This instruction makes a copy of one register into another. The source
+ *  register Rr is left unchanged, while the destination register Rd is loaded
+ *  with a copy of Rr.
+ */
+static bool trans_MOV(DisasContext *ctx, arg_MOV *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv Rr = cpu_r[a->rr];
+
+    tcg_gen_mov_tl(Rd, Rr);
+
+    return true;
+}
+
+/*
+ *  This instruction makes a copy of one register pair into another register
+ *  pair. The source register pair Rr+1:Rr is left unchanged, while the
+ *  destination register pair Rd+1:Rd is loaded with a copy of Rr + 1:Rr.  This
+ *  instruction is not available in all devices. Refer to the device specific
+ *  instruction set summary.
+ */
+static bool trans_MOVW(DisasContext *ctx, arg_MOVW *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_MOVW)) {
+        return true;
+    }
+
+    TCGv RdL = cpu_r[a->rd];
+    TCGv RdH = cpu_r[a->rd + 1];
+    TCGv RrL = cpu_r[a->rr];
+    TCGv RrH = cpu_r[a->rr + 1];
+
+    tcg_gen_mov_tl(RdH, RrH);
+    tcg_gen_mov_tl(RdL, RrL);
+
+    return true;
+}
+
+/*
+ * Loads an 8 bit constant directly to register 16 to 31.
+ */
+static bool trans_LDI(DisasContext *ctx, arg_LDI *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    int imm = a->imm;
+
+    tcg_gen_movi_tl(Rd, imm);
+
+    return true;
+}
+
+/*
+ *  Loads one byte from the data space to a register. For parts with SRAM,
+ *  the data space consists of the Register File, I/O memory and internal SRAM
+ *  (and external SRAM if applicable). For parts without SRAM, the data space
+ *  consists of the register file only. The EEPROM has a separate address space.
+ *  A 16-bit address must be supplied. Memory access is limited to the current
+ *  data segment of 64KB. The LDS instruction uses the RAMPD Register to access
+ *  memory above 64KB. To access another data segment in devices with more than
+ *  64KB data space, the RAMPD in register in the I/O area has to be changed.
+ *  This instruction is not available in all devices. Refer to the device
+ *  specific instruction set summary.
+ */
+static bool trans_LDS(DisasContext *ctx, arg_LDS *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = tcg_temp_new_i32();
+    TCGv H = cpu_rampD;
+    a->imm = next_word(ctx);
+
+    tcg_gen_mov_tl(addr, H); /* addr = H:M:L */
+    tcg_gen_shli_tl(addr, addr, 16);
+    tcg_gen_ori_tl(addr, addr, a->imm);
+
+    gen_data_load(ctx, Rd, addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+/*
+ *  Loads one byte indirect from the data space to a register. For parts
+ *  with SRAM, the data space consists of the Register File, I/O memory and
+ *  internal SRAM (and external SRAM if applicable). For parts without SRAM, the
+ *  data space consists of the Register File only. In some parts the Flash
+ *  Memory has been mapped to the data space and can be read using this command.
+ *  The EEPROM has a separate address space.  The data location is pointed to by
+ *  the X (16 bits) Pointer Register in the Register File. Memory access is
+ *  limited to the current data segment of 64KB. To access another data segment
+ *  in devices with more than 64KB data space, the RAMPX in register in the I/O
+ *  area has to be changed.  The X-pointer Register can either be left unchanged
+ *  by the operation, or it can be post-incremented or predecremented.  These
+ *  features are especially suited for accessing arrays, tables, and Stack
+ *  Pointer usage of the X-pointer Register. Note that only the low byte of the
+ *  X-pointer is updated in devices with no more than 256 bytes data space. For
+ *  such devices, the high byte of the pointer is not used by this instruction
+ *  and can be used for other purposes. The RAMPX Register in the I/O area is
+ *  updated in parts with more than 64KB data space or more than 64KB Program
+ *  memory, and the increment/decrement is added to the entire 24-bit address on
+ *  such devices.  Not all variants of this instruction is available in all
+ *  devices. Refer to the device specific instruction set summary.  In the
+ *  Reduced Core tinyAVR the LD instruction can be used to achieve the same
+ *  operation as LPM since the program memory is mapped to the data memory
+ *  space.
+ */
+static bool trans_LDX1(DisasContext *ctx, arg_LDX1 *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_xaddr();
+
+    gen_data_load(ctx, Rd, addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_LDX2(DisasContext *ctx, arg_LDX2 *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_xaddr();
+
+    gen_data_load(ctx, Rd, addr);
+    tcg_gen_addi_tl(addr, addr, 1); /* addr = addr + 1 */
+
+    gen_set_xaddr(addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_LDX3(DisasContext *ctx, arg_LDX3 *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_xaddr();
+
+    tcg_gen_subi_tl(addr, addr, 1); /* addr = addr - 1 */
+    gen_data_load(ctx, Rd, addr);
+    gen_set_xaddr(addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+/*
+ *  Loads one byte indirect with or without displacement from the data space
+ *  to a register. For parts with SRAM, the data space consists of the Register
+ *  File, I/O memory and internal SRAM (and external SRAM if applicable). For
+ *  parts without SRAM, the data space consists of the Register File only. In
+ *  some parts the Flash Memory has been mapped to the data space and can be
+ *  read using this command. The EEPROM has a separate address space.  The data
+ *  location is pointed to by the Y (16 bits) Pointer Register in the Register
+ *  File. Memory access is limited to the current data segment of 64KB. To
+ *  access another data segment in devices with more than 64KB data space, the
+ *  RAMPY in register in the I/O area has to be changed.  The Y-pointer Register
+ *  can either be left unchanged by the operation, or it can be post-incremented
+ *  or predecremented.  These features are especially suited for accessing
+ *  arrays, tables, and Stack Pointer usage of the Y-pointer Register. Note that
+ *  only the low byte of the Y-pointer is updated in devices with no more than
+ *  256 bytes data space. For such devices, the high byte of the pointer is not
+ *  used by this instruction and can be used for other purposes. The RAMPY
+ *  Register in the I/O area is updated in parts with more than 64KB data space
+ *  or more than 64KB Program memory, and the increment/decrement/displacement
+ *  is added to the entire 24-bit address on such devices.  Not all variants of
+ *  this instruction is available in all devices. Refer to the device specific
+ *  instruction set summary.  In the Reduced Core tinyAVR the LD instruction can
+ *  be used to achieve the same operation as LPM since the program memory is
+ *  mapped to the data memory space.
+ */
+static bool trans_LDY2(DisasContext *ctx, arg_LDY2 *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_yaddr();
+
+    gen_data_load(ctx, Rd, addr);
+    tcg_gen_addi_tl(addr, addr, 1); /* addr = addr + 1 */
+
+    gen_set_yaddr(addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_LDY3(DisasContext *ctx, arg_LDY3 *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_yaddr();
+
+    tcg_gen_subi_tl(addr, addr, 1); /* addr = addr - 1 */
+    gen_data_load(ctx, Rd, addr);
+    gen_set_yaddr(addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_LDDY(DisasContext *ctx, arg_LDDY *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_yaddr();
+
+    tcg_gen_addi_tl(addr, addr, a->imm); /* addr = addr + q */
+    gen_data_load(ctx, Rd, addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+/*
+ *  Loads one byte indirect with or without displacement from the data space
+ *  to a register. For parts with SRAM, the data space consists of the Register
+ *  File, I/O memory and internal SRAM (and external SRAM if applicable). For
+ *  parts without SRAM, the data space consists of the Register File only. In
+ *  some parts the Flash Memory has been mapped to the data space and can be
+ *  read using this command. The EEPROM has a separate address space.  The data
+ *  location is pointed to by the Z (16 bits) Pointer Register in the Register
+ *  File. Memory access is limited to the current data segment of 64KB. To
+ *  access another data segment in devices with more than 64KB data space, the
+ *  RAMPZ in register in the I/O area has to be changed.  The Z-pointer Register
+ *  can either be left unchanged by the operation, or it can be post-incremented
+ *  or predecremented.  These features are especially suited for Stack Pointer
+ *  usage of the Z-pointer Register, however because the Z-pointer Register can
+ *  be used for indirect subroutine calls, indirect jumps and table lookup, it
+ *  is often more convenient to use the X or Y-pointer as a dedicated Stack
+ *  Pointer. Note that only the low byte of the Z-pointer is updated in devices
+ *  with no more than 256 bytes data space. For such devices, the high byte of
+ *  the pointer is not used by this instruction and can be used for other
+ *  purposes. The RAMPZ Register in the I/O area is updated in parts with more
+ *  than 64KB data space or more than 64KB Program memory, and the
+ *  increment/decrement/displacement is added to the entire 24-bit address on
+ *  such devices.  Not all variants of this instruction is available in all
+ *  devices. Refer to the device specific instruction set summary.  In the
+ *  Reduced Core tinyAVR the LD instruction can be used to achieve the same
+ *  operation as LPM since the program memory is mapped to the data memory
+ *  space.  For using the Z-pointer for table lookup in Program memory see the
+ *  LPM and ELPM instructions.
+ */
+static bool trans_LDZ2(DisasContext *ctx, arg_LDZ2 *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_zaddr();
+
+    gen_data_load(ctx, Rd, addr);
+    tcg_gen_addi_tl(addr, addr, 1); /* addr = addr + 1 */
+
+    gen_set_zaddr(addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_LDZ3(DisasContext *ctx, arg_LDZ3 *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_zaddr();
+
+    tcg_gen_subi_tl(addr, addr, 1); /* addr = addr - 1 */
+    gen_data_load(ctx, Rd, addr);
+
+    gen_set_zaddr(addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_LDDZ(DisasContext *ctx, arg_LDDZ *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_zaddr();
+
+    tcg_gen_addi_tl(addr, addr, a->imm); /* addr = addr + q */
+    gen_data_load(ctx, Rd, addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+/*
+ *  Stores one byte from a Register to the data space. For parts with SRAM,
+ *  the data space consists of the Register File, I/O memory and internal SRAM
+ *  (and external SRAM if applicable). For parts without SRAM, the data space
+ *  consists of the Register File only. The EEPROM has a separate address space.
+ *  A 16-bit address must be supplied. Memory access is limited to the current
+ *  data segment of 64KB. The STS instruction uses the RAMPD Register to access
+ *  memory above 64KB. To access another data segment in devices with more than
+ *  64KB data space, the RAMPD in register in the I/O area has to be changed.
+ *  This instruction is not available in all devices. Refer to the device
+ *  specific instruction set summary.
+ */
+static bool trans_STS(DisasContext *ctx, arg_STS *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = tcg_temp_new_i32();
+    TCGv H = cpu_rampD;
+    a->imm = next_word(ctx);
+
+    tcg_gen_mov_tl(addr, H); /* addr = H:M:L */
+    tcg_gen_shli_tl(addr, addr, 16);
+    tcg_gen_ori_tl(addr, addr, a->imm);
+    gen_data_store(ctx, Rd, addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+/*
+ * Stores one byte indirect from a register to data space. For parts with SRAM,
+ * the data space consists of the Register File, I/O memory, and internal SRAM
+ * (and external SRAM if applicable). For parts without SRAM, the data space
+ * consists of the Register File only. The EEPROM has a separate address space.
+ *
+ * The data location is pointed to by the X (16 bits) Pointer Register in the
+ * Register File. Memory access is limited to the current data segment of 64KB.
+ * To access another data segment in devices with more than 64KB data space, the
+ * RAMPX in register in the I/O area has to be changed.
+ *
+ * The X-pointer Register can either be left unchanged by the operation, or it
+ * can be post-incremented or pre-decremented. These features are especially
+ * suited for accessing arrays, tables, and Stack Pointer usage of the
+ * X-pointer Register. Note that only the low byte of the X-pointer is updated
+ * in devices with no more than 256 bytes data space. For such devices, the high
+ * byte of the pointer is not used by this instruction and can be used for other
+ * purposes. The RAMPX Register in the I/O area is updated in parts with more
+ * than 64KB data space or more than 64KB Program memory, and the increment /
+ * decrement is added to the entire 24-bit address on such devices.
+ */
+static bool trans_STX1(DisasContext *ctx, arg_STX1 *a)
+{
+    TCGv Rd = cpu_r[a->rr];
+    TCGv addr = gen_get_xaddr();
+
+    gen_data_store(ctx, Rd, addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_STX2(DisasContext *ctx, arg_STX2 *a)
+{
+    TCGv Rd = cpu_r[a->rr];
+    TCGv addr = gen_get_xaddr();
+
+    gen_data_store(ctx, Rd, addr);
+    tcg_gen_addi_tl(addr, addr, 1); /* addr = addr + 1 */
+    gen_set_xaddr(addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_STX3(DisasContext *ctx, arg_STX3 *a)
+{
+    TCGv Rd = cpu_r[a->rr];
+    TCGv addr = gen_get_xaddr();
+
+    tcg_gen_subi_tl(addr, addr, 1); /* addr = addr - 1 */
+    gen_data_store(ctx, Rd, addr);
+    gen_set_xaddr(addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+/*
+ * Stores one byte indirect with or without displacement from a register to data
+ * space. For parts with SRAM, the data space consists of the Register File, I/O
+ * memory, and internal SRAM (and external SRAM if applicable). For parts
+ * without SRAM, the data space consists of the Register File only. The EEPROM
+ * has a separate address space.
+ *
+ * The data location is pointed to by the Y (16 bits) Pointer Register in the
+ * Register File. Memory access is limited to the current data segment of 64KB.
+ * To access another data segment in devices with more than 64KB data space, the
+ * RAMPY in register in the I/O area has to be changed.
+ *
+ * The Y-pointer Register can either be left unchanged by the operation, or it
+ * can be post-incremented or pre-decremented. These features are especially
+ * suited for accessing arrays, tables, and Stack Pointer usage of the Y-pointer
+ * Register. Note that only the low byte of the Y-pointer is updated in devices
+ * with no more than 256 bytes data space. For such devices, the high byte of
+ * the pointer is not used by this instruction and can be used for other
+ * purposes. The RAMPY Register in the I/O area is updated in parts with more
+ * than 64KB data space or more than 64KB Program memory, and the increment /
+ * decrement / displacement is added to the entire 24-bit address on such
+ * devices.
+ */
+static bool trans_STY2(DisasContext *ctx, arg_STY2 *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_yaddr();
+
+    gen_data_store(ctx, Rd, addr);
+    tcg_gen_addi_tl(addr, addr, 1); /* addr = addr + 1 */
+    gen_set_yaddr(addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_STY3(DisasContext *ctx, arg_STY3 *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_yaddr();
+
+    tcg_gen_subi_tl(addr, addr, 1); /* addr = addr - 1 */
+    gen_data_store(ctx, Rd, addr);
+    gen_set_yaddr(addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_STDY(DisasContext *ctx, arg_STDY *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_yaddr();
+
+    tcg_gen_addi_tl(addr, addr, a->imm); /* addr = addr + q */
+    gen_data_store(ctx, Rd, addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+/*
+ * Stores one byte indirect with or without displacement from a register to data
+ * space. For parts with SRAM, the data space consists of the Register File, I/O
+ * memory, and internal SRAM (and external SRAM if applicable). For parts
+ * without SRAM, the data space consists of the Register File only. The EEPROM
+ * has a separate address space.
+ *
+ * The data location is pointed to by the Y (16 bits) Pointer Register in the
+ * Register File. Memory access is limited to the current data segment of 64KB.
+ * To access another data segment in devices with more than 64KB data space, the
+ * RAMPY in register in the I/O area has to be changed.
+ *
+ * The Y-pointer Register can either be left unchanged by the operation, or it
+ * can be post-incremented or pre-decremented. These features are especially
+ * suited for accessing arrays, tables, and Stack Pointer usage of the Y-pointer
+ * Register. Note that only the low byte of the Y-pointer is updated in devices
+ * with no more than 256 bytes data space. For such devices, the high byte of
+ * the pointer is not used by this instruction and can be used for other
+ * purposes. The RAMPY Register in the I/O area is updated in parts with more
+ * than 64KB data space or more than 64KB Program memory, and the increment /
+ * decrement / displacement is added to the entire 24-bit address on such
+ * devices.
+ */
+static bool trans_STZ2(DisasContext *ctx, arg_STZ2 *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_zaddr();
+
+    gen_data_store(ctx, Rd, addr);
+    tcg_gen_addi_tl(addr, addr, 1); /* addr = addr + 1 */
+
+    gen_set_zaddr(addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_STZ3(DisasContext *ctx, arg_STZ3 *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_zaddr();
+
+    tcg_gen_subi_tl(addr, addr, 1); /* addr = addr - 1 */
+    gen_data_store(ctx, Rd, addr);
+
+    gen_set_zaddr(addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_STDZ(DisasContext *ctx, arg_STDZ *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_zaddr();
+
+    tcg_gen_addi_tl(addr, addr, a->imm); /* addr = addr + q */
+    gen_data_store(ctx, Rd, addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+/*
+ *  Loads one byte pointed to by the Z-register into the destination
+ *  register Rd. This instruction features a 100% space effective constant
+ *  initialization or constant data fetch. The Program memory is organized in
+ *  16-bit words while the Z-pointer is a byte address. Thus, the least
+ *  significant bit of the Z-pointer selects either low byte (ZLSB = 0) or high
+ *  byte (ZLSB = 1). This instruction can address the first 64KB (32K words) of
+ *  Program memory. The Zpointer Register can either be left unchanged by the
+ *  operation, or it can be incremented. The incrementation does not apply to
+ *  the RAMPZ Register.
+ *
+ *  Devices with Self-Programming capability can use the LPM instruction to read
+ *  the Fuse and Lock bit values.
+ */
+static bool trans_LPM1(DisasContext *ctx, arg_LPM1 *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_LPM)) {
+        return true;
+    }
+
+    TCGv Rd = cpu_r[0];
+    TCGv addr = tcg_temp_new_i32();
+    TCGv H = cpu_r[31];
+    TCGv L = cpu_r[30];
+
+    tcg_gen_shli_tl(addr, H, 8); /* addr = H:L */
+    tcg_gen_or_tl(addr, addr, L);
+    tcg_gen_qemu_ld8u(Rd, addr, MMU_CODE_IDX); /* Rd = mem[addr] */
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_LPM2(DisasContext *ctx, arg_LPM2 *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_LPM)) {
+        return true;
+    }
+
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = tcg_temp_new_i32();
+    TCGv H = cpu_r[31];
+    TCGv L = cpu_r[30];
+
+    tcg_gen_shli_tl(addr, H, 8); /* addr = H:L */
+    tcg_gen_or_tl(addr, addr, L);
+    tcg_gen_qemu_ld8u(Rd, addr, MMU_CODE_IDX); /* Rd = mem[addr] */
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_LPMX(DisasContext *ctx, arg_LPMX *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_LPMX)) {
+        return true;
+    }
+
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = tcg_temp_new_i32();
+    TCGv H = cpu_r[31];
+    TCGv L = cpu_r[30];
+
+    tcg_gen_shli_tl(addr, H, 8); /* addr = H:L */
+    tcg_gen_or_tl(addr, addr, L);
+    tcg_gen_qemu_ld8u(Rd, addr, MMU_CODE_IDX); /* Rd = mem[addr] */
+    tcg_gen_addi_tl(addr, addr, 1); /* addr = addr + 1 */
+    tcg_gen_andi_tl(L, addr, 0xff);
+    tcg_gen_shri_tl(addr, addr, 8);
+    tcg_gen_andi_tl(H, addr, 0xff);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+/*
+ *  Loads one byte pointed to by the Z-register and the RAMPZ Register in
+ *  the I/O space, and places this byte in the destination register Rd. This
+ *  instruction features a 100% space effective constant initialization or
+ *  constant data fetch. The Program memory is organized in 16-bit words while
+ *  the Z-pointer is a byte address. Thus, the least significant bit of the
+ *  Z-pointer selects either low byte (ZLSB = 0) or high byte (ZLSB = 1). This
+ *  instruction can address the entire Program memory space. The Z-pointer
+ *  Register can either be left unchanged by the operation, or it can be
+ *  incremented. The incrementation applies to the entire 24-bit concatenation
+ *  of the RAMPZ and Z-pointer Registers.
+ *
+ *  Devices with Self-Programming capability can use the ELPM instruction to
+ *  read the Fuse and Lock bit value.
+ */
+static bool trans_ELPM1(DisasContext *ctx, arg_ELPM1 *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_ELPM)) {
+        return true;
+    }
+
+    TCGv Rd = cpu_r[0];
+    TCGv addr = gen_get_zaddr();
+
+    tcg_gen_qemu_ld8u(Rd, addr, MMU_CODE_IDX); /* Rd = mem[addr] */
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_ELPM2(DisasContext *ctx, arg_ELPM2 *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_ELPM)) {
+        return true;
+    }
+
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_zaddr();
+
+    tcg_gen_qemu_ld8u(Rd, addr, MMU_CODE_IDX); /* Rd = mem[addr] */
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+static bool trans_ELPMX(DisasContext *ctx, arg_ELPMX *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_ELPMX)) {
+        return true;
+    }
+
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_zaddr();
+
+    tcg_gen_qemu_ld8u(Rd, addr, MMU_CODE_IDX); /* Rd = mem[addr] */
+    tcg_gen_addi_tl(addr, addr, 1); /* addr = addr + 1 */
+    gen_set_zaddr(addr);
+
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+/*
+ *  SPM can be used to erase a page in the Program memory, to write a page
+ *  in the Program memory (that is already erased), and to set Boot Loader Lock
+ *  bits. In some devices, the Program memory can be written one word at a time,
+ *  in other devices an entire page can be programmed simultaneously after first
+ *  filling a temporary page buffer. In all cases, the Program memory must be
+ *  erased one page at a time. When erasing the Program memory, the RAMPZ and
+ *  Z-register are used as page address. When writing the Program memory, the
+ *  RAMPZ and Z-register are used as page or word address, and the R1:R0
+ *  register pair is used as data(1). When setting the Boot Loader Lock bits,
+ *  the R1:R0 register pair is used as data. Refer to the device documentation
+ *  for detailed description of SPM usage. This instruction can address the
+ *  entire Program memory.
+ *
+ *  The SPM instruction is not available in all devices. Refer to the device
+ *  specific instruction set summary.
+ *
+ *  Note: 1. R1 determines the instruction high byte, and R0 determines the
+ *  instruction low byte.
+ */
+static bool trans_SPM(DisasContext *ctx, arg_SPM *a)
+{
+    /* TODO */
+    if (!avr_have_feature(ctx, AVR_FEATURE_SPM)) {
+        return true;
+    }
+
+    return true;
+}
+
+static bool trans_SPMX(DisasContext *ctx, arg_SPMX *a)
+{
+    /* TODO */
+    if (!avr_have_feature(ctx, AVR_FEATURE_SPMX)) {
+        return true;
+    }
+
+    return true;
+}
+
+/*
+ *  Loads data from the I/O Space (Ports, Timers, Configuration Registers,
+ *  etc.) into register Rd in the Register File.
+ */
+static bool trans_IN(DisasContext *ctx, arg_IN *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv port = tcg_const_i32(a->imm);
+
+    gen_helper_inb(Rd, cpu_env, port);
+
+    tcg_temp_free_i32(port);
+
+    return true;
+}
+
+/*
+ *  Stores data from register Rr in the Register File to I/O Space (Ports,
+ *  Timers, Configuration Registers, etc.).
+ */
+static bool trans_OUT(DisasContext *ctx, arg_OUT *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv port = tcg_const_i32(a->imm);
+
+    gen_helper_outb(cpu_env, port, Rd);
+
+    tcg_temp_free_i32(port);
+
+    return true;
+}
+
+/*
+ *  This instruction stores the contents of register Rr on the STACK. The
+ *  Stack Pointer is post-decremented by 1 after the PUSH.  This instruction is
+ *  not available in all devices. Refer to the device specific instruction set
+ *  summary.
+ */
+static bool trans_PUSH(DisasContext *ctx, arg_PUSH *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+
+    gen_data_store(ctx, Rd, cpu_sp);
+    tcg_gen_subi_tl(cpu_sp, cpu_sp, 1);
+
+    return true;
+}
+
+/*
+ *  This instruction loads register Rd with a byte from the STACK. The Stack
+ *  Pointer is pre-incremented by 1 before the POP.  This instruction is not
+ *  available in all devices. Refer to the device specific instruction set
+ *  summary.
+ */
+static bool trans_POP(DisasContext *ctx, arg_POP *a)
+{
+    /*
+     * Using a temp to work around some strange behaviour:
+     * tcg_gen_addi_tl(cpu_sp, cpu_sp, 1);
+     * gen_data_load(ctx, Rd, cpu_sp);
+     * seems to cause the add to happen twice.
+     * This doesn't happen if either the add or the load is removed.
+     */
+    TCGv t1 = tcg_temp_new_i32();
+    TCGv Rd = cpu_r[a->rd];
+
+    tcg_gen_addi_tl(t1, cpu_sp, 1);
+    gen_data_load(ctx, Rd, t1);
+    tcg_gen_mov_tl(cpu_sp, t1);
+
+    return true;
+}
+
+/*
+ *  Exchanges one byte indirect between register and data space.  The data
+ *  location is pointed to by the Z (16 bits) Pointer Register in the Register
+ *  File. Memory access is limited to the current data segment of 64KB. To
+ *  access another data segment in devices with more than 64KB data space, the
+ *  RAMPZ in register in the I/O area has to be changed.
+ *
+ *  The Z-pointer Register is left unchanged by the operation. This instruction
+ *  is especially suited for writing/reading status bits stored in SRAM.
+ */
+static bool trans_XCH(DisasContext *ctx, arg_XCH *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_RMW)) {
+        return true;
+    }
+
+    TCGv Rd = cpu_r[a->rd];
+    TCGv t0 = tcg_temp_new_i32();
+    TCGv addr = gen_get_zaddr();
+
+    gen_data_load(ctx, t0, addr);
+    gen_data_store(ctx, Rd, addr);
+    tcg_gen_mov_tl(Rd, t0);
+
+    tcg_temp_free_i32(t0);
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+/*
+ *  Load one byte indirect from data space to register and set bits in data
+ *  space specified by the register. The instruction can only be used towards
+ *  internal SRAM.  The data location is pointed to by the Z (16 bits) Pointer
+ *  Register in the Register File. Memory access is limited to the current data
+ *  segment of 64KB. To access another data segment in devices with more than
+ *  64KB data space, the RAMPZ in register in the I/O area has to be changed.
+ *
+ *  The Z-pointer Register is left unchanged by the operation. This instruction
+ *  is especially suited for setting status bits stored in SRAM.
+ */
+static bool trans_LAS(DisasContext *ctx, arg_LAS *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_RMW)) {
+        return true;
+    }
+
+    TCGv Rr = cpu_r[a->rd];
+    TCGv addr = gen_get_zaddr();
+    TCGv t0 = tcg_temp_new_i32();
+    TCGv t1 = tcg_temp_new_i32();
+
+    gen_data_load(ctx, t0, addr); /* t0 = mem[addr] */
+    tcg_gen_or_tl(t1, t0, Rr);
+    tcg_gen_mov_tl(Rr, t0); /* Rr = t0 */
+    gen_data_store(ctx, t1, addr); /* mem[addr] = t1 */
+
+    tcg_temp_free_i32(t1);
+    tcg_temp_free_i32(t0);
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+/*
+ *  Load one byte indirect from data space to register and stores and clear
+ *  the bits in data space specified by the register. The instruction can
+ *  only be used towards internal SRAM.  The data location is pointed to by
+ *  the Z (16 bits) Pointer Register in the Register File. Memory access is
+ *  limited to the current data segment of 64KB. To access another data
+ *  segment in devices with more than 64KB data space, the RAMPZ in register
+ *  in the I/O area has to be changed.
+ *
+ *  The Z-pointer Register is left unchanged by the operation. This instruction
+ *  is especially suited for clearing status bits stored in SRAM.
+ */
+static bool trans_LAC(DisasContext *ctx, arg_LAC *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_RMW)) {
+        return true;
+    }
+
+    TCGv Rr = cpu_r[a->rd];
+    TCGv addr = gen_get_zaddr();
+    TCGv t0 = tcg_temp_new_i32();
+    TCGv t1 = tcg_temp_new_i32();
+
+    gen_data_load(ctx, t0, addr); /* t0 = mem[addr] */
+    tcg_gen_andc_tl(t1, t0, Rr); /* t1 = t0 & (0xff - Rr) = t0 & ~Rr */
+    tcg_gen_mov_tl(Rr, t0); /* Rr = t0 */
+    gen_data_store(ctx, t1, addr); /* mem[addr] = t1 */
+
+    tcg_temp_free_i32(t1);
+    tcg_temp_free_i32(t0);
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+
+/*
+ *  Load one byte indirect from data space to register and toggles bits in
+ *  the data space specified by the register.  The instruction can only be used
+ *  towards SRAM.  The data location is pointed to by the Z (16 bits) Pointer
+ *  Register in the Register File. Memory access is limited to the current data
+ *  segment of 64KB. To access another data segment in devices with more than
+ *  64KB data space, the RAMPZ in register in the I/O area has to be changed.
+ *
+ *  The Z-pointer Register is left unchanged by the operation. This instruction
+ *  is especially suited for changing status bits stored in SRAM.
+ */
+static bool trans_LAT(DisasContext *ctx, arg_LAT *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_RMW)) {
+        return true;
+    }
+
+    TCGv Rd = cpu_r[a->rd];
+    TCGv addr = gen_get_zaddr();
+    TCGv t0 = tcg_temp_new_i32();
+    TCGv t1 = tcg_temp_new_i32();
+
+    gen_data_load(ctx, t0, addr); /* t0 = mem[addr] */
+    tcg_gen_xor_tl(t1, t0, Rd);
+    tcg_gen_mov_tl(Rd, t0); /* Rd = t0 */
+    gen_data_store(ctx, t1, addr); /* mem[addr] = t1 */
+
+    tcg_temp_free_i32(t1);
+    tcg_temp_free_i32(t0);
+    tcg_temp_free_i32(addr);
+
+    return true;
+}
+
+/*
+ * Bit and Bit-test Instructions
+ */
+static void gen_rshift_ZNVSf(TCGv R)
+{
+    tcg_gen_setcondi_tl(TCG_COND_EQ, cpu_Zf, R, 0); /* Zf = R == 0 */
+    tcg_gen_shri_tl(cpu_Nf, R, 7); /* Nf = R(7) */
+    tcg_gen_xor_tl(cpu_Vf, cpu_Nf, cpu_Cf);
+    tcg_gen_xor_tl(cpu_Sf, cpu_Nf, cpu_Vf); /* Sf = Nf ^ Vf */
+}
+
+/*
+ *  Shifts all bits in Rd one place to the right. Bit 7 is cleared. Bit 0 is
+ *  loaded into the C Flag of the SREG. This operation effectively divides an
+ *  unsigned value by two. The C Flag can be used to round the result.
+ */
+static bool trans_LSR(DisasContext *ctx, arg_LSR *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+
+    tcg_gen_andi_tl(cpu_Cf, Rd, 1);
+    tcg_gen_shri_tl(Rd, Rd, 1);
+
+    /* update status register */
+    tcg_gen_setcondi_tl(TCG_COND_EQ, cpu_Zf, Rd, 0); /* Zf = Rd == 0 */
+    tcg_gen_movi_tl(cpu_Nf, 0);
+    tcg_gen_mov_tl(cpu_Vf, cpu_Cf);
+    tcg_gen_mov_tl(cpu_Sf, cpu_Vf);
+
+    return true;
+}
+
+/*
+ *  Shifts all bits in Rd one place to the right. The C Flag is shifted into
+ *  bit 7 of Rd. Bit 0 is shifted into the C Flag.  This operation, combined
+ *  with ASR, effectively divides multi-byte signed values by two. Combined with
+ *  LSR it effectively divides multi-byte unsigned values by two. The Carry Flag
+ *  can be used to round the result.
+ */
+static bool trans_ROR(DisasContext *ctx, arg_ROR *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv t0 = tcg_temp_new_i32();
+
+    tcg_gen_shli_tl(t0, cpu_Cf, 7);
+
+    /* update status register */
+    tcg_gen_andi_tl(cpu_Cf, Rd, 1);
+
+    /* update output register */
+    tcg_gen_shri_tl(Rd, Rd, 1);
+    tcg_gen_or_tl(Rd, Rd, t0);
+
+    /* update status register */
+    gen_rshift_ZNVSf(Rd);
+
+    tcg_temp_free_i32(t0);
+
+    return true;
+}
+
+/*
+ *  Shifts all bits in Rd one place to the right. Bit 7 is held constant. Bit 0
+ *  is loaded into the C Flag of the SREG. This operation effectively divides a
+ *  signed value by two without changing its sign. The Carry Flag can be used to
+ *  round the result.
+ */
+static bool trans_ASR(DisasContext *ctx, arg_ASR *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv t0 = tcg_temp_new_i32();
+
+    /* update status register */
+    tcg_gen_andi_tl(cpu_Cf, Rd, 1); /* Cf = Rd(0) */
+
+    /* update output register */
+    tcg_gen_andi_tl(t0, Rd, 0x80); /* Rd = (Rd & 0x80) | (Rd >> 1) */
+    tcg_gen_shri_tl(Rd, Rd, 1);
+    tcg_gen_or_tl(Rd, Rd, t0);
+
+    /* update status register */
+    gen_rshift_ZNVSf(Rd);
+
+    tcg_temp_free_i32(t0);
+
+    return true;
+}
+
+/*
+ *  Swaps high and low nibbles in a register.
+ */
+static bool trans_SWAP(DisasContext *ctx, arg_SWAP *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv t0 = tcg_temp_new_i32();
+    TCGv t1 = tcg_temp_new_i32();
+
+    tcg_gen_andi_tl(t0, Rd, 0x0f);
+    tcg_gen_shli_tl(t0, t0, 4);
+    tcg_gen_andi_tl(t1, Rd, 0xf0);
+    tcg_gen_shri_tl(t1, t1, 4);
+    tcg_gen_or_tl(Rd, t0, t1);
+
+    tcg_temp_free_i32(t1);
+    tcg_temp_free_i32(t0);
+
+    return true;
+}
+
+/*
+ *  Sets a specified bit in an I/O Register. This instruction operates on
+ *  the lower 32 I/O Registers -- addresses 0-31.
+ */
+static bool trans_SBI(DisasContext *ctx, arg_SBI *a)
+{
+    TCGv data = tcg_temp_new_i32();
+    TCGv port = tcg_const_i32(a->reg);
+
+    gen_helper_inb(data, cpu_env, port);
+    tcg_gen_ori_tl(data, data, 1 << a->bit);
+    gen_helper_outb(cpu_env, port, data);
+
+    tcg_temp_free_i32(port);
+    tcg_temp_free_i32(data);
+
+    return true;
+}
+
+/*
+ *  Clears a specified bit in an I/O Register. This instruction operates on
+ *  the lower 32 I/O Registers -- addresses 0-31.
+ */
+static bool trans_CBI(DisasContext *ctx, arg_CBI *a)
+{
+    TCGv data = tcg_temp_new_i32();
+    TCGv port = tcg_const_i32(a->reg);
+
+    gen_helper_inb(data, cpu_env, port);
+    tcg_gen_andi_tl(data, data, ~(1 << a->bit));
+    gen_helper_outb(cpu_env, port, data);
+
+    tcg_temp_free_i32(data);
+    tcg_temp_free_i32(port);
+
+    return true;
+}
+
+/*
+ *  Stores bit b from Rd to the T Flag in SREG (Status Register).
+ */
+static bool trans_BST(DisasContext *ctx, arg_BST *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+
+    tcg_gen_andi_tl(cpu_Tf, Rd, 1 << a->bit);
+    tcg_gen_shri_tl(cpu_Tf, cpu_Tf, a->bit);
+
+    return true;
+}
+
+/*
+ *  Copies the T Flag in the SREG (Status Register) to bit b in register Rd.
+ */
+static bool trans_BLD(DisasContext *ctx, arg_BLD *a)
+{
+    TCGv Rd = cpu_r[a->rd];
+    TCGv t1 = tcg_temp_new_i32();
+
+    tcg_gen_andi_tl(Rd, Rd, ~(1u << a->bit)); /* clear bit */
+    tcg_gen_shli_tl(t1, cpu_Tf, a->bit); /* create mask */
+    tcg_gen_or_tl(Rd, Rd, t1);
+
+    tcg_temp_free_i32(t1);
+
+    return true;
+}
+
+/*
+ *  Sets a single Flag or bit in SREG.
+ */
+static bool trans_BSET(DisasContext *ctx, arg_BSET *a)
+{
+    switch (a->bit) {
+    case 0x00:
+        tcg_gen_movi_tl(cpu_Cf, 0x01);
+        break;
+    case 0x01:
+        tcg_gen_movi_tl(cpu_Zf, 0x01);
+        break;
+    case 0x02:
+        tcg_gen_movi_tl(cpu_Nf, 0x01);
+        break;
+    case 0x03:
+        tcg_gen_movi_tl(cpu_Vf, 0x01);
+        break;
+    case 0x04:
+        tcg_gen_movi_tl(cpu_Sf, 0x01);
+        break;
+    case 0x05:
+        tcg_gen_movi_tl(cpu_Hf, 0x01);
+        break;
+    case 0x06:
+        tcg_gen_movi_tl(cpu_Tf, 0x01);
+        break;
+    case 0x07:
+        tcg_gen_movi_tl(cpu_If, 0x01);
+        break;
+    }
+
+    return true;
+}
+
+/*
+ *  Clears a single Flag in SREG.
+ */
+static bool trans_BCLR(DisasContext *ctx, arg_BCLR *a)
+{
+    switch (a->bit) {
+    case 0x00:
+        tcg_gen_movi_tl(cpu_Cf, 0x00);
+        break;
+    case 0x01:
+        tcg_gen_movi_tl(cpu_Zf, 0x00);
+        break;
+    case 0x02:
+        tcg_gen_movi_tl(cpu_Nf, 0x00);
+        break;
+    case 0x03:
+        tcg_gen_movi_tl(cpu_Vf, 0x00);
+        break;
+    case 0x04:
+        tcg_gen_movi_tl(cpu_Sf, 0x00);
+        break;
+    case 0x05:
+        tcg_gen_movi_tl(cpu_Hf, 0x00);
+        break;
+    case 0x06:
+        tcg_gen_movi_tl(cpu_Tf, 0x00);
+        break;
+    case 0x07:
+        tcg_gen_movi_tl(cpu_If, 0x00);
+        break;
+    }
+
+    return true;
+}
+
+/*
+ * MCU Control Instructions
+ */
+
+/*
+ *  The BREAK instruction is used by the On-chip Debug system, and is
+ *  normally not used in the application software. When the BREAK instruction is
+ *  executed, the AVR CPU is set in the Stopped Mode. This gives the On-chip
+ *  Debugger access to internal resources.  If any Lock bits are set, or either
+ *  the JTAGEN or OCDEN Fuses are unprogrammed, the CPU will treat the BREAK
+ *  instruction as a NOP and will not enter the Stopped mode.  This instruction
+ *  is not available in all devices. Refer to the device specific instruction
+ *  set summary.
+ */
+static bool trans_BREAK(DisasContext *ctx, arg_BREAK *a)
+{
+    if (!avr_have_feature(ctx, AVR_FEATURE_BREAK)) {
+        return true;
+    }
+
+#ifdef BREAKPOINT_ON_BREAK
+    tcg_gen_movi_tl(cpu_pc, ctx->npc - 1);
+    gen_helper_debug(cpu_env);
+    ctx->bstate = DISAS_EXIT;
+#else
+    /* NOP */
+#endif
+
+    return true;
+}
+
+/*
+ *  This instruction performs a single cycle No Operation.
+ */
+static bool trans_NOP(DisasContext *ctx, arg_NOP *a)
+{
+
+    /* NOP */
+
+    return true;
+}
+
+/*
+ *  This instruction sets the circuit in sleep mode defined by the MCU
+ *  Control Register.
+ */
+static bool trans_SLEEP(DisasContext *ctx, arg_SLEEP *a)
+{
+    gen_helper_sleep(cpu_env);
+    ctx->bstate = DISAS_NORETURN;
+    return true;
+}
+
+/*
+ *  This instruction resets the Watchdog Timer. This instruction must be
+ *  executed within a limited time given by the WD prescaler. See the Watchdog
+ *  Timer hardware specification.
+ */
+static bool trans_WDR(DisasContext *ctx, arg_WDR *a)
+{
+    gen_helper_wdr(cpu_env);
+
+    return true;
+}
+
+/*
+ *  Core translation mechanism functions:
+ *
+ *    - translate()
+ *    - canonicalize_skip()
+ *    - gen_intermediate_code()
+ *    - restore_state_to_opc()
+ *
+ */
+static void translate(DisasContext *ctx)
+{
+    uint32_t opcode = next_word(ctx);
+
+    if (!decode_insn(ctx, opcode)) {
+        gen_helper_unsupported(cpu_env);
+        ctx->bstate = DISAS_NORETURN;
+    }
+}
+
+/* Standardize the cpu_skip condition to NE.  */
+static bool canonicalize_skip(DisasContext *ctx)
+{
+    switch (ctx->skip_cond) {
+    case TCG_COND_NEVER:
+        /* Normal case: cpu_skip is known to be false.  */
+        return false;
+
+    case TCG_COND_ALWAYS:
+        /*
+         * Breakpoint case: cpu_skip is known to be true, via TB_FLAGS_SKIP.
+         * The breakpoint is on the instruction being skipped, at the start
+         * of the TranslationBlock.  No need to update.
+         */
+        return false;
+
+    case TCG_COND_NE:
+        if (ctx->skip_var1 == NULL) {
+            tcg_gen_mov_tl(cpu_skip, ctx->skip_var0);
+        } else {
+            tcg_gen_xor_tl(cpu_skip, ctx->skip_var0, ctx->skip_var1);
+            ctx->skip_var1 = NULL;
+        }
+        break;
+
+    default:
+        /* Convert to a NE condition vs 0. */
+        if (ctx->skip_var1 == NULL) {
+            tcg_gen_setcondi_tl(ctx->skip_cond, cpu_skip, ctx->skip_var0, 0);
+        } else {
+            tcg_gen_setcond_tl(ctx->skip_cond, cpu_skip,
+                               ctx->skip_var0, ctx->skip_var1);
+            ctx->skip_var1 = NULL;
+        }
+        ctx->skip_cond = TCG_COND_NE;
+        break;
+    }
+    if (ctx->free_skip_var0) {
+        tcg_temp_free(ctx->skip_var0);
+        ctx->free_skip_var0 = false;
+    }
+    ctx->skip_var0 = cpu_skip;
+    return true;
+}
+
+void gen_intermediate_code(CPUState *cs, TranslationBlock *tb, int max_insns)
+{
+    CPUAVRState *env = cs->env_ptr;
+    DisasContext ctx = {
+        .tb = tb,
+        .cs = cs,
+        .env = env,
+        .memidx = 0,
+        .bstate = DISAS_NEXT,
+        .skip_cond = TCG_COND_NEVER,
+        .singlestep = cs->singlestep_enabled,
+    };
+    target_ulong pc_start = tb->pc / 2;
+    int num_insns = 0;
+
+    if (tb->flags & TB_FLAGS_FULL_ACCESS) {
+        /*
+         * This flag is set by ST/LD instruction we will regenerate it ONLY
+         * with mem/cpu memory access instead of mem access
+         */
+        max_insns = 1;
+    }
+    if (ctx.singlestep) {
+        max_insns = 1;
+    }
+
+    gen_tb_start(tb);
+
+    ctx.npc = pc_start;
+    if (tb->flags & TB_FLAGS_SKIP) {
+        ctx.skip_cond = TCG_COND_ALWAYS;
+        ctx.skip_var0 = cpu_skip;
+    }
+
+    do {
+        TCGLabel *skip_label = NULL;
+
+        /* translate current instruction */
+        tcg_gen_insn_start(ctx.npc);
+        num_insns++;
+
+        /*
+         * this is due to some strange GDB behavior
+         * let's assume main has address 0x100
+         * b main   - sets breakpoint at address 0x00000100 (code)
+         * b *0x100 - sets breakpoint at address 0x00800100 (data)
+         */
+        if (unlikely(!ctx.singlestep &&
+                (cpu_breakpoint_test(cs, OFFSET_CODE + ctx.npc * 2, BP_ANY) ||
+                 cpu_breakpoint_test(cs, OFFSET_DATA + ctx.npc * 2, BP_ANY)))) {
+            canonicalize_skip(&ctx);
+            tcg_gen_movi_tl(cpu_pc, ctx.npc);
+            gen_helper_debug(cpu_env);
+            goto done_generating;
+        }
+
+        /* Conditionally skip the next instruction, if indicated.  */
+        if (ctx.skip_cond != TCG_COND_NEVER) {
+            skip_label = gen_new_label();
+            if (ctx.skip_var0 == cpu_skip) {
+                /*
+                 * Copy cpu_skip so that we may zero it before the branch.
+                 * This ensures that cpu_skip is non-zero after the label
+                 * if and only if the skipped insn itself sets a skip.
+                 */
+                ctx.free_skip_var0 = true;
+                ctx.skip_var0 = tcg_temp_new();
+                tcg_gen_mov_tl(ctx.skip_var0, cpu_skip);
+                tcg_gen_movi_tl(cpu_skip, 0);
+            }
+            if (ctx.skip_var1 == NULL) {
+                tcg_gen_brcondi_tl(ctx.skip_cond, ctx.skip_var0, 0, skip_label);
+            } else {
+                tcg_gen_brcond_tl(ctx.skip_cond, ctx.skip_var0,
+                                  ctx.skip_var1, skip_label);
+                ctx.skip_var1 = NULL;
+            }
+            if (ctx.free_skip_var0) {
+                tcg_temp_free(ctx.skip_var0);
+                ctx.free_skip_var0 = false;
+            }
+            ctx.skip_cond = TCG_COND_NEVER;
+            ctx.skip_var0 = NULL;
+        }
+
+        translate(&ctx);
+
+        if (skip_label) {
+            canonicalize_skip(&ctx);
+            gen_set_label(skip_label);
+            if (ctx.bstate == DISAS_NORETURN) {
+                ctx.bstate = DISAS_CHAIN;
+            }
+        }
+    } while (ctx.bstate == DISAS_NEXT
+             && num_insns < max_insns
+             && (ctx.npc - pc_start) * 2 < TARGET_PAGE_SIZE - 4
+             && !tcg_op_buf_full());
+
+    if (tb->cflags & CF_LAST_IO) {
+        gen_io_end();
+    }
+
+    bool nonconst_skip = canonicalize_skip(&ctx);
+
+    switch (ctx.bstate) {
+    case DISAS_NORETURN:
+        assert(!nonconst_skip);
+        break;
+    case DISAS_NEXT:
+    case DISAS_TOO_MANY:
+    case DISAS_CHAIN:
+        if (!nonconst_skip) {
+            /* Note gen_goto_tb checks singlestep.  */
+            gen_goto_tb(&ctx, 1, ctx.npc);
+            break;
+        }
+        tcg_gen_movi_tl(cpu_pc, ctx.npc);
+        /* fall through */
+    case DISAS_LOOKUP:
+        if (!ctx.singlestep) {
+            tcg_gen_lookup_and_goto_ptr();
+            break;
+        }
+        /* fall through */
+    case DISAS_EXIT:
+        if (ctx.singlestep) {
+            gen_helper_debug(cpu_env);
+        } else {
+            tcg_gen_exit_tb(NULL, 0);
+        }
+        break;
+    default:
+        g_assert_not_reached();
+    }
+
+done_generating:
+    gen_tb_end(tb, num_insns);
+
+    tb->size = (ctx.npc - pc_start) * 2;
+    tb->icount = num_insns;
+
+#ifdef DEBUG_DISAS
+    if (qemu_loglevel_mask(CPU_LOG_TB_IN_ASM)
+        && qemu_log_in_addr_range(tb->pc)) {
+        FILE *fd;
+        fd = qemu_log_lock();
+        qemu_log("IN: %s\n", lookup_symbol(tb->pc));
+        log_target_disas(cs, tb->pc, tb->size);
+        qemu_log("\n");
+        qemu_log_unlock(fd);
+    }
+#endif
+}
+
+void restore_state_to_opc(CPUAVRState *env, TranslationBlock *tb,
+                            target_ulong *data)
+{
+    env->pc_w = data[0];
+}
diff --git a/tests/acceptance/machine_avr6.py b/tests/acceptance/machine_avr6.py
new file mode 100644
index 0000000000..6baf4e9c7f
--- /dev/null
+++ b/tests/acceptance/machine_avr6.py
@@ -0,0 +1,50 @@
+#
+# QEMU AVR acceptance tests
+#
+# Copyright (c) 2019-2020 Michael Rolnik <mrolnik@gmail.com>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+import time
+
+from avocado_qemu import Test
+
+class AVR6Machine(Test):
+    timeout = 5
+
+    def test_freertos(self):
+        """
+        :avocado: tags=arch:avr
+        :avocado: tags=machine:arduino-mega-2560-v3
+        """
+        """
+        https://github.com/seharris/qemu-avr-tests/raw/master/free-rtos/Demo/AVR_ATMega2560_GCC/demo.elf
+        constantly prints out 'ABCDEFGHIJKLMNOPQRSTUVWXABCDEFGHIJKLMNOPQRSTUVWX'
+        """
+        rom_url = ('https://github.com/seharris/qemu-avr-tests'
+                   '/raw/36c3e67b8755dcf/free-rtos/Demo'
+                   '/AVR_ATMega2560_GCC/demo.elf')
+        rom_hash = '7eb521f511ca8f2622e0a3c5e8dd686efbb911d4'
+        rom_path = self.fetch_asset(rom_url, asset_hash=rom_hash)
+
+        self.vm.add_args('-bios', rom_path)
+        self.vm.add_args('-nographic')
+        self.vm.launch()
+
+        time.sleep(2)
+        self.vm.shutdown()
+
+        self.assertIn('ABCDEFGHIJKLMNOPQRSTUVWXABCDEFGHIJKLMNOPQRSTUVWX',
+                self.vm.get_log())
diff --git a/tests/qtest/Makefile.include b/tests/qtest/Makefile.include
index 98af2c2d93..994ac47399 100644
--- a/tests/qtest/Makefile.include
+++ b/tests/qtest/Makefile.include
@@ -66,6 +66,8 @@ check-qtest-i386-y += numa-test
 
 check-qtest-x86_64-y += $(check-qtest-i386-y)
 
+check-qtest-avr-y += boot-serial-test
+
 check-qtest-alpha-y += boot-serial-test
 check-qtest-alpha-$(CONFIG_VGA) += display-vga-test
 
diff --git a/tests/qtest/boot-serial-test.c b/tests/qtest/boot-serial-test.c
index 85a3614286..bfe7624dc6 100644
--- a/tests/qtest/boot-serial-test.c
+++ b/tests/qtest/boot-serial-test.c
@@ -17,6 +17,15 @@
 #include "libqtest.h"
 #include "libqos/libqos-spapr.h"
 
+static const uint8_t bios_avr[] = {
+    0x88, 0xe0,             /* ldi r24, 0x08   */
+    0x80, 0x93, 0xc1, 0x00, /* sts 0x00C1, r24 ; Enable tx */
+    0x86, 0xe0,             /* ldi r24, 0x06   */
+    0x80, 0x93, 0xc2, 0x00, /* sts 0x00C2, r24 ; Set the data bits to 8 */
+    0x84, 0xe5,             /* ldi r24, 0x54   */
+    0x80, 0x93, 0xc6, 0x00, /* sts 0x00C6, r24 ; Output 'T' */
+};
+
 static const uint8_t kernel_mcf5208[] = {
     0x41, 0xf9, 0xfc, 0x06, 0x00, 0x00,     /* lea 0xfc060000,%a0 */
     0x10, 0x3c, 0x00, 0x54,                 /* move.b #'T',%d0 */
@@ -104,6 +113,8 @@ typedef struct testdef {
 
 static testdef_t tests[] = {
     { "alpha", "clipper", "", "PCI:" },
+    { "avr", "arduino-duemilanove", "", "T", sizeof(bios_avr), NULL, bios_avr },
+    { "avr", "arduino-mega-2560-v3", "", "T", sizeof(bios_avr), NULL, bios_avr},
     { "ppc", "ppce500", "", "U-Boot" },
     { "ppc", "40p", "-vga none -boot d", "Trying cd:," },
     { "ppc", "g3beige", "", "PowerPC,750" },
diff --git a/tests/qtest/machine-none-test.c b/tests/qtest/machine-none-test.c
index 8b7abea8af..57107f1aec 100644
--- a/tests/qtest/machine-none-test.c
+++ b/tests/qtest/machine-none-test.c
@@ -27,6 +27,7 @@ static struct arch2cpu cpus_map[] = {
     /* tested targets list */
     { "arm", "cortex-a15" },
     { "aarch64", "cortex-a57" },
+    { "avr", "avr6-avr-cpu" },
     { "x86_64", "qemu64,apic-id=0" },
     { "i386", "qemu32,apic-id=0" },
     { "alpha", "ev67" },
author	Peter Maydell <peter.maydell@linaro.org>	2020-07-11 19:27:59 +0100
committer	Peter Maydell <peter.maydell@linaro.org>	2020-07-11 19:27:59 +0100
commit	d34498309cff7560ac90c422c56e3137e6a64b19 (patch)
tree	0a5207cc1a1a637b5abb3db997b503c1ce9f5375
parent	2033cc6efa98b831d7839e367aa7d5aa74d0750f (diff)
parent	19b293472f1514b5424ef4d9b092e02bd9b106c2 (diff)