Merge remote-tracking branch 'remotes/palmer/tags/riscv-for-master-5.0-sf2' into staging

RISC-V Patches for the 5.0 Soft Freeze, Part 2

This is a fairly light-weight pull request, but I wanted to send it out to
avoid the Goldfish stuff getting buried as the next PR should contain the H
extension implementation.

As far as this PR goes, it contains:

* The addition of syscon device tree nodes for reboot and poweroff, which
  allows Linux to control QEMU without an additional driver.  The existing
  device was already compatible with the syscon interface.
* A fix to our GDB stub to avoid confusing XLEN and FLEN, specifically useful
  for rv32id-based systems.
* A device emulation for the Goldfish RTC device, a simple memory-mapped RTC.
* The addition of the Goldfish RTC device to the RISC-V virt board.

This passes "make check" and boots buildroot for me.

# gpg: Signature made Mon 10 Feb 2020 21:28:04 GMT
# gpg:                using RSA key 2B3C3747446843B24A943A7A2E1319F35FBB1889
# gpg:                issuer "palmer@dabbelt.com"
# gpg: Good signature from "Palmer Dabbelt <palmer@dabbelt.com>" [unknown]
# gpg:                 aka "Palmer Dabbelt <palmer@sifive.com>" [unknown]
# gpg:                 aka "Palmer Dabbelt <palmerdabbelt@google.com>" [unknown]
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 00CE 76D1 8349 60DF CE88  6DF8 EF4C A150 2CCB AB41
#      Subkey fingerprint: 2B3C 3747 4468 43B2 4A94  3A7A 2E13 19F3 5FBB 1889

* remotes/palmer/tags/riscv-for-master-5.0-sf2:
  MAINTAINERS: Add maintainer entry for Goldfish RTC
  riscv: virt: Use Goldfish RTC device
  hw: rtc: Add Goldfish RTC device
  riscv: Separate FPU register size from core register size in gdbstub [v2]
  riscv/virt: Add syscon reboot and poweroff DT nodes

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

6 files changed, 332 insertions, 4 deletions

diff --git a/hw/riscv/Kconfig b/hw/riscv/Kconfig
index b12660b9f8..ff9fbe958a 100644
--- a/hw/riscv/Kconfig
+++ b/hw/riscv/Kconfig
@@ -34,6 +34,7 @@ config RISCV_VIRT
     select PCI
     select HART
     select SERIAL
+    select GOLDFISH_RTC
     select VIRTIO_MMIO
     select PCI_EXPRESS_GENERIC_BRIDGE
     select PFLASH_CFI01
diff --git a/hw/riscv/virt.c b/hw/riscv/virt.c
index c44b865959..7f9e1e5176 100644
--- a/hw/riscv/virt.c
+++ b/hw/riscv/virt.c
@@ -58,6 +58,7 @@ static const struct MemmapEntry {
     [VIRT_DEBUG] =       {        0x0,         0x100 },
     [VIRT_MROM] =        {     0x1000,       0x11000 },
     [VIRT_TEST] =        {   0x100000,        0x1000 },
+    [VIRT_RTC] =         {   0x101000,        0x1000 },
     [VIRT_CLINT] =       {  0x2000000,       0x10000 },
     [VIRT_PLIC] =        {  0xc000000,     0x4000000 },
     [VIRT_UART0] =       { 0x10000000,         0x100 },
@@ -182,11 +183,10 @@ static void create_fdt(RISCVVirtState *s, const struct MemmapEntry *memmap,
     uint64_t mem_size, const char *cmdline)
 {
     void *fdt;
-    int cpu;
+    int cpu, i;
     uint32_t *cells;
     char *nodename;
-    uint32_t plic_phandle, phandle = 1;
-    int i;
+    uint32_t plic_phandle, test_phandle, phandle = 1;
     hwaddr flashsize = virt_memmap[VIRT_FLASH].size / 2;
     hwaddr flashbase = virt_memmap[VIRT_FLASH].base;
 
@@ -356,16 +356,35 @@ static void create_fdt(RISCVVirtState *s, const struct MemmapEntry *memmap,
     create_pcie_irq_map(fdt, nodename, plic_phandle);
     g_free(nodename);
 
+    test_phandle = phandle++;
     nodename = g_strdup_printf("/test@%lx",
         (long)memmap[VIRT_TEST].base);
     qemu_fdt_add_subnode(fdt, nodename);
     {
-        const char compat[] = "sifive,test1\0sifive,test0";
+        const char compat[] = "sifive,test1\0sifive,test0\0syscon";
         qemu_fdt_setprop(fdt, nodename, "compatible", compat, sizeof(compat));
     }
     qemu_fdt_setprop_cells(fdt, nodename, "reg",
         0x0, memmap[VIRT_TEST].base,
         0x0, memmap[VIRT_TEST].size);
+    qemu_fdt_setprop_cell(fdt, nodename, "phandle", test_phandle);
+    test_phandle = qemu_fdt_get_phandle(fdt, nodename);
+    g_free(nodename);
+
+    nodename = g_strdup_printf("/reboot");
+    qemu_fdt_add_subnode(fdt, nodename);
+    qemu_fdt_setprop_string(fdt, nodename, "compatible", "syscon-reboot");
+    qemu_fdt_setprop_cell(fdt, nodename, "regmap", test_phandle);
+    qemu_fdt_setprop_cell(fdt, nodename, "offset", 0x0);
+    qemu_fdt_setprop_cell(fdt, nodename, "value", FINISHER_RESET);
+    g_free(nodename);
+
+    nodename = g_strdup_printf("/poweroff");
+    qemu_fdt_add_subnode(fdt, nodename);
+    qemu_fdt_setprop_string(fdt, nodename, "compatible", "syscon-poweroff");
+    qemu_fdt_setprop_cell(fdt, nodename, "regmap", test_phandle);
+    qemu_fdt_setprop_cell(fdt, nodename, "offset", 0x0);
+    qemu_fdt_setprop_cell(fdt, nodename, "value", FINISHER_PASS);
     g_free(nodename);
 
     nodename = g_strdup_printf("/uart@%lx",
@@ -386,6 +405,18 @@ static void create_fdt(RISCVVirtState *s, const struct MemmapEntry *memmap,
     }
     g_free(nodename);
 
+    nodename = g_strdup_printf("/rtc@%lx",
+        (long)memmap[VIRT_RTC].base);
+    qemu_fdt_add_subnode(fdt, nodename);
+    qemu_fdt_setprop_string(fdt, nodename, "compatible",
+        "google,goldfish-rtc");
+    qemu_fdt_setprop_cells(fdt, nodename, "reg",
+        0x0, memmap[VIRT_RTC].base,
+        0x0, memmap[VIRT_RTC].size);
+    qemu_fdt_setprop_cell(fdt, nodename, "interrupt-parent", plic_phandle);
+    qemu_fdt_setprop_cell(fdt, nodename, "interrupts", RTC_IRQ);
+    g_free(nodename);
+
     nodename = g_strdup_printf("/flash@%" PRIx64, flashbase);
     qemu_fdt_add_subnode(s->fdt, nodename);
     qemu_fdt_setprop_string(s->fdt, nodename, "compatible", "cfi-flash");
@@ -583,6 +614,9 @@ static void riscv_virt_board_init(MachineState *machine)
         0, qdev_get_gpio_in(DEVICE(s->plic), UART0_IRQ), 399193,
         serial_hd(0), DEVICE_LITTLE_ENDIAN);
 
+    sysbus_create_simple("goldfish_rtc", memmap[VIRT_RTC].base,
+        qdev_get_gpio_in(DEVICE(s->plic), RTC_IRQ));
+
     virt_flash_create(s);
 
     for (i = 0; i < ARRAY_SIZE(s->flash); i++) {
diff --git a/hw/rtc/Kconfig b/hw/rtc/Kconfig
index 3dc2dd6888..f06e133b8a 100644
--- a/hw/rtc/Kconfig
+++ b/hw/rtc/Kconfig
@@ -22,3 +22,6 @@ config MC146818RTC
 
 config SUN4V_RTC
     bool
+
+config GOLDFISH_RTC
+    bool
diff --git a/hw/rtc/Makefile.objs b/hw/rtc/Makefile.objs
index 8dc9fcd3a9..aa208d0d10 100644
--- a/hw/rtc/Makefile.objs
+++ b/hw/rtc/Makefile.objs
@@ -11,3 +11,4 @@ common-obj-$(CONFIG_EXYNOS4) += exynos4210_rtc.o
 obj-$(CONFIG_MC146818RTC) += mc146818rtc.o
 common-obj-$(CONFIG_SUN4V_RTC) += sun4v-rtc.o
 common-obj-$(CONFIG_ASPEED_SOC) += aspeed_rtc.o
+common-obj-$(CONFIG_GOLDFISH_RTC) += goldfish_rtc.o
diff --git a/hw/rtc/goldfish_rtc.c b/hw/rtc/goldfish_rtc.c
new file mode 100644
index 0000000000..01e9d2b083
--- /dev/null
+++ b/hw/rtc/goldfish_rtc.c
@@ -0,0 +1,285 @@
+/*
+ * Goldfish virtual platform RTC
+ *
+ * Copyright (C) 2019 Western Digital Corporation or its affiliates.
+ *
+ * For more details on Google Goldfish virtual platform refer:
+ * https://android.googlesource.com/platform/external/qemu/+/refs/heads/emu-2.0-release/docs/GOLDFISH-VIRTUAL-HARDWARE.TXT
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2 or later, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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 "qemu-common.h"
+#include "hw/rtc/goldfish_rtc.h"
+#include "migration/vmstate.h"
+#include "hw/irq.h"
+#include "hw/qdev-properties.h"
+#include "hw/sysbus.h"
+#include "qemu/bitops.h"
+#include "qemu/timer.h"
+#include "sysemu/sysemu.h"
+#include "qemu/cutils.h"
+#include "qemu/log.h"
+
+#include "trace.h"
+
+#define RTC_TIME_LOW            0x00
+#define RTC_TIME_HIGH           0x04
+#define RTC_ALARM_LOW           0x08
+#define RTC_ALARM_HIGH          0x0c
+#define RTC_IRQ_ENABLED         0x10
+#define RTC_CLEAR_ALARM         0x14
+#define RTC_ALARM_STATUS        0x18
+#define RTC_CLEAR_INTERRUPT     0x1c
+
+static void goldfish_rtc_update(GoldfishRTCState *s)
+{
+    qemu_set_irq(s->irq, (s->irq_pending & s->irq_enabled) ? 1 : 0);
+}
+
+static void goldfish_rtc_interrupt(void *opaque)
+{
+    GoldfishRTCState *s = (GoldfishRTCState *)opaque;
+
+    s->alarm_running = 0;
+    s->irq_pending = 1;
+    goldfish_rtc_update(s);
+}
+
+static uint64_t goldfish_rtc_get_count(GoldfishRTCState *s)
+{
+    return s->tick_offset + (uint64_t)qemu_clock_get_ns(rtc_clock);
+}
+
+static void goldfish_rtc_clear_alarm(GoldfishRTCState *s)
+{
+    timer_del(s->timer);
+    s->alarm_running = 0;
+}
+
+static void goldfish_rtc_set_alarm(GoldfishRTCState *s)
+{
+    uint64_t ticks = goldfish_rtc_get_count(s);
+    uint64_t event = s->alarm_next;
+
+    if (event <= ticks) {
+        goldfish_rtc_clear_alarm(s);
+        goldfish_rtc_interrupt(s);
+    } else {
+        /*
+         * We should be setting timer expiry to:
+         *     qemu_clock_get_ns(rtc_clock) + (event - ticks)
+         * but this is equivalent to:
+         *     event - s->tick_offset
+         */
+        timer_mod(s->timer, event - s->tick_offset);
+        s->alarm_running = 1;
+    }
+}
+
+static uint64_t goldfish_rtc_read(void *opaque, hwaddr offset,
+                                  unsigned size)
+{
+    GoldfishRTCState *s = opaque;
+    uint64_t r = 0;
+
+    switch (offset) {
+    case RTC_TIME_LOW:
+        r = goldfish_rtc_get_count(s) & 0xffffffff;
+        break;
+    case RTC_TIME_HIGH:
+        r = goldfish_rtc_get_count(s) >> 32;
+        break;
+    case RTC_ALARM_LOW:
+        r = s->alarm_next & 0xffffffff;
+        break;
+    case RTC_ALARM_HIGH:
+        r = s->alarm_next >> 32;
+        break;
+    case RTC_IRQ_ENABLED:
+        r = s->irq_enabled;
+        break;
+    case RTC_ALARM_STATUS:
+        r = s->alarm_running;
+        break;
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR,
+                  "%s: offset 0x%x is UNIMP.\n", __func__, (uint32_t)offset);
+        break;
+    }
+
+    trace_goldfish_rtc_read(offset, r);
+
+    return r;
+}
+
+static void goldfish_rtc_write(void *opaque, hwaddr offset,
+                               uint64_t value, unsigned size)
+{
+    GoldfishRTCState *s = opaque;
+    uint64_t current_tick, new_tick;
+
+    switch (offset) {
+    case RTC_TIME_LOW:
+        current_tick = goldfish_rtc_get_count(s);
+        new_tick = deposit64(current_tick, 0, 32, value);
+        s->tick_offset += new_tick - current_tick;
+        break;
+    case RTC_TIME_HIGH:
+        current_tick = goldfish_rtc_get_count(s);
+        new_tick = deposit64(current_tick, 32, 32, value);
+        s->tick_offset += new_tick - current_tick;
+        break;
+    case RTC_ALARM_LOW:
+        s->alarm_next = deposit64(s->alarm_next, 0, 32, value);
+        goldfish_rtc_set_alarm(s);
+        break;
+    case RTC_ALARM_HIGH:
+        s->alarm_next = deposit64(s->alarm_next, 32, 32, value);
+        break;
+    case RTC_IRQ_ENABLED:
+        s->irq_enabled = (uint32_t)(value & 0x1);
+        goldfish_rtc_update(s);
+        break;
+    case RTC_CLEAR_ALARM:
+        goldfish_rtc_clear_alarm(s);
+        break;
+    case RTC_CLEAR_INTERRUPT:
+        s->irq_pending = 0;
+        goldfish_rtc_update(s);
+        break;
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR,
+                  "%s: offset 0x%x is UNIMP.\n", __func__, (uint32_t)offset);
+        break;
+    }
+
+    trace_goldfish_rtc_write(offset, value);
+}
+
+static int goldfish_rtc_pre_save(void *opaque)
+{
+    uint64_t delta;
+    GoldfishRTCState *s = opaque;
+
+    /*
+     * We want to migrate this offset, which sounds straightforward.
+     * Unfortunately, we cannot directly pass tick_offset because
+     * rtc_clock on destination Host might not be same source Host.
+     *
+     * To tackle, this we pass tick_offset relative to vm_clock from
+     * source Host and make it relative to rtc_clock at destination Host.
+     */
+    delta = qemu_clock_get_ns(rtc_clock) -
+            qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+    s->tick_offset_vmstate = s->tick_offset + delta;
+
+    return 0;
+}
+
+static int goldfish_rtc_post_load(void *opaque, int version_id)
+{
+    uint64_t delta;
+    GoldfishRTCState *s = opaque;
+
+    /*
+     * We extract tick_offset from tick_offset_vmstate by doing
+     * reverse math compared to pre_save() function.
+     */
+    delta = qemu_clock_get_ns(rtc_clock) -
+            qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+    s->tick_offset = s->tick_offset_vmstate - delta;
+
+    return 0;
+}
+
+static const MemoryRegionOps goldfish_rtc_ops = {
+    .read = goldfish_rtc_read,
+    .write = goldfish_rtc_write,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+    .valid = {
+        .min_access_size = 4,
+        .max_access_size = 4
+    }
+};
+
+static const VMStateDescription goldfish_rtc_vmstate = {
+    .name = TYPE_GOLDFISH_RTC,
+    .version_id = 1,
+    .pre_save = goldfish_rtc_pre_save,
+    .post_load = goldfish_rtc_post_load,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT64(tick_offset_vmstate, GoldfishRTCState),
+        VMSTATE_UINT64(alarm_next, GoldfishRTCState),
+        VMSTATE_UINT32(alarm_running, GoldfishRTCState),
+        VMSTATE_UINT32(irq_pending, GoldfishRTCState),
+        VMSTATE_UINT32(irq_enabled, GoldfishRTCState),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static void goldfish_rtc_reset(DeviceState *dev)
+{
+    GoldfishRTCState *s = GOLDFISH_RTC(dev);
+    struct tm tm;
+
+    timer_del(s->timer);
+
+    qemu_get_timedate(&tm, 0);
+    s->tick_offset = mktimegm(&tm);
+    s->tick_offset *= NANOSECONDS_PER_SECOND;
+    s->tick_offset -= qemu_clock_get_ns(rtc_clock);
+    s->tick_offset_vmstate = 0;
+    s->alarm_next = 0;
+    s->alarm_running = 0;
+    s->irq_pending = 0;
+    s->irq_enabled = 0;
+}
+
+static void goldfish_rtc_realize(DeviceState *d, Error **errp)
+{
+    SysBusDevice *dev = SYS_BUS_DEVICE(d);
+    GoldfishRTCState *s = GOLDFISH_RTC(d);
+
+    memory_region_init_io(&s->iomem, OBJECT(s), &goldfish_rtc_ops, s,
+                          "goldfish_rtc", 0x24);
+    sysbus_init_mmio(dev, &s->iomem);
+
+    sysbus_init_irq(dev, &s->irq);
+
+    s->timer = timer_new_ns(rtc_clock, goldfish_rtc_interrupt, s);
+}
+
+static void goldfish_rtc_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->realize = goldfish_rtc_realize;
+    dc->reset = goldfish_rtc_reset;
+    dc->vmsd = &goldfish_rtc_vmstate;
+}
+
+static const TypeInfo goldfish_rtc_info = {
+    .name          = TYPE_GOLDFISH_RTC,
+    .parent        = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(GoldfishRTCState),
+    .class_init    = goldfish_rtc_class_init,
+};
+
+static void goldfish_rtc_register_types(void)
+{
+    type_register_static(&goldfish_rtc_info);
+}
+
+type_init(goldfish_rtc_register_types)
diff --git a/hw/rtc/trace-events b/hw/rtc/trace-events
index 52c1566198..c9894e1747 100644
--- a/hw/rtc/trace-events
+++ b/hw/rtc/trace-events
@@ -23,3 +23,7 @@ m48txx_nvram_io_read(uint64_t addr, uint64_t value) "io read addr:0x%04" PRIx64
 m48txx_nvram_io_write(uint64_t addr, uint64_t value) "io write addr:0x%04" PRIx64 " value:0x%02" PRIx64
 m48txx_nvram_mem_read(uint32_t addr, uint32_t value) "mem read addr:0x%04x value:0x%02x"
 m48txx_nvram_mem_write(uint32_t addr, uint32_t value) "mem write addr:0x%04x value:0x%02x"
+
+# goldfish_rtc.c
+goldfish_rtc_read(uint64_t addr, uint64_t value) "addr 0x%02" PRIx64 " value 0x%08" PRIx64
+goldfish_rtc_write(uint64_t addr, uint64_t value) "addr 0x%02" PRIx64 " value 0x%08" PRIx64