hw/misc/stm32l4x5_rcc: Implement STM32L4x5_RCC skeleton

Add the necessary files to add a simple RCC implementation with just
reads from and writes to registers. Also instantiate the RCC in the
STM32L4x5_SoC. It is needed for accurate emulation of all the SoC
clocks and timers.

Signed-off-by: Arnaud Minier <arnaud.minier@telecom-paris.fr>
Signed-off-by: Inès Varhol <ines.varhol@telecom-paris.fr>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20240303140643.81957-2-arnaud.minier@telecom-paris.fr
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

4 files changed, 454 insertions, 0 deletions

diff --git a/hw/misc/Kconfig b/hw/misc/Kconfig
index 83ad849b62..1e08785b83 100644
--- a/hw/misc/Kconfig
+++ b/hw/misc/Kconfig
@@ -97,6 +97,9 @@ config STM32L4X5_EXTI
 config STM32L4X5_SYSCFG
     bool
 
+config STM32L4X5_RCC
+    bool
+
 config MIPS_ITU
     bool
 
diff --git a/hw/misc/meson.build b/hw/misc/meson.build
index 746686835b..265b2c2627 100644
--- a/hw/misc/meson.build
+++ b/hw/misc/meson.build
@@ -113,6 +113,7 @@ system_ss.add(when: 'CONFIG_STM32F4XX_SYSCFG', if_true: files('stm32f4xx_syscfg.
 system_ss.add(when: 'CONFIG_STM32F4XX_EXTI', if_true: files('stm32f4xx_exti.c'))
 system_ss.add(when: 'CONFIG_STM32L4X5_EXTI', if_true: files('stm32l4x5_exti.c'))
 system_ss.add(when: 'CONFIG_STM32L4X5_SYSCFG', if_true: files('stm32l4x5_syscfg.c'))
+system_ss.add(when: 'CONFIG_STM32L4X5_RCC', if_true: files('stm32l4x5_rcc.c'))
 system_ss.add(when: 'CONFIG_MPS2_FPGAIO', if_true: files('mps2-fpgaio.c'))
 system_ss.add(when: 'CONFIG_MPS2_SCC', if_true: files('mps2-scc.c'))
 
diff --git a/hw/misc/stm32l4x5_rcc.c b/hw/misc/stm32l4x5_rcc.c
new file mode 100644
index 0000000000..269e50b85a
--- /dev/null
+++ b/hw/misc/stm32l4x5_rcc.c
@@ -0,0 +1,446 @@
+/*
+ * STM32L4X5 RCC (Reset and clock control)
+ *
+ * Copyright (c) 2023 Arnaud Minier <arnaud.minier@telecom-paris.fr>
+ * Copyright (c) 2023 Inès Varhol <ines.varhol@telecom-paris.fr>
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ * The reference used is the STMicroElectronics RM0351 Reference manual
+ * for STM32L4x5 and STM32L4x6 advanced Arm ® -based 32-bit MCUs.
+ *
+ * Inspired by the BCM2835 CPRMAN clock manager implementation by Luc Michel.
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/log.h"
+#include "qemu/module.h"
+#include "qemu/timer.h"
+#include "qapi/error.h"
+#include "migration/vmstate.h"
+#include "hw/misc/stm32l4x5_rcc.h"
+#include "hw/misc/stm32l4x5_rcc_internals.h"
+#include "hw/clock.h"
+#include "hw/irq.h"
+#include "hw/qdev-clock.h"
+#include "hw/qdev-properties.h"
+#include "hw/qdev-properties-system.h"
+#include "trace.h"
+
+#define HSE_DEFAULT_FRQ 48000000ULL
+#define HSI_FRQ 16000000ULL
+#define MSI_DEFAULT_FRQ 4000000ULL
+#define LSE_FRQ 32768ULL
+#define LSI_FRQ 32000ULL
+
+static void rcc_update_irq(Stm32l4x5RccState *s)
+{
+    if (s->cifr & CIFR_IRQ_MASK) {
+        qemu_irq_raise(s->irq);
+    } else {
+        qemu_irq_lower(s->irq);
+    }
+}
+
+static void stm32l4x5_rcc_reset_hold(Object *obj)
+{
+    Stm32l4x5RccState *s = STM32L4X5_RCC(obj);
+    s->cr = 0x00000063;
+    /*
+     * Factory-programmed calibration data
+     * From the reference manual: 0x10XX 00XX
+     * Value taken from a real card.
+     */
+    s->icscr = 0x106E0082;
+    s->cfgr = 0x0;
+    s->pllcfgr = 0x00001000;
+    s->pllsai1cfgr = 0x00001000;
+    s->pllsai2cfgr = 0x00001000;
+    s->cier = 0x0;
+    s->cifr = 0x0;
+    s->ahb1rstr = 0x0;
+    s->ahb2rstr = 0x0;
+    s->ahb3rstr = 0x0;
+    s->apb1rstr1 = 0x0;
+    s->apb1rstr2 = 0x0;
+    s->apb2rstr = 0x0;
+    s->ahb1enr = 0x00000100;
+    s->ahb2enr = 0x0;
+    s->ahb3enr = 0x0;
+    s->apb1enr1 = 0x0;
+    s->apb1enr2 = 0x0;
+    s->apb2enr = 0x0;
+    s->ahb1smenr = 0x00011303;
+    s->ahb2smenr = 0x000532FF;
+    s->ahb3smenr =  0x00000101;
+    s->apb1smenr1 = 0xF2FECA3F;
+    s->apb1smenr2 = 0x00000025;
+    s->apb2smenr = 0x01677C01;
+    s->ccipr = 0x0;
+    s->bdcr = 0x0;
+    s->csr = 0x0C000600;
+}
+
+static uint64_t stm32l4x5_rcc_read(void *opaque, hwaddr addr,
+                                     unsigned int size)
+{
+    Stm32l4x5RccState *s = opaque;
+    uint64_t retvalue = 0;
+
+    switch (addr) {
+    case A_CR:
+        retvalue = s->cr;
+        break;
+    case A_ICSCR:
+        retvalue = s->icscr;
+        break;
+    case A_CFGR:
+        retvalue = s->cfgr;
+        break;
+    case A_PLLCFGR:
+        retvalue = s->pllcfgr;
+        break;
+    case A_PLLSAI1CFGR:
+        retvalue = s->pllsai1cfgr;
+        break;
+    case A_PLLSAI2CFGR:
+        retvalue = s->pllsai2cfgr;
+        break;
+    case A_CIER:
+        retvalue = s->cier;
+        break;
+    case A_CIFR:
+        retvalue = s->cifr;
+        break;
+    case A_CICR:
+        /* CICR is write only, return the reset value = 0 */
+        break;
+    case A_AHB1RSTR:
+        retvalue = s->ahb1rstr;
+        break;
+    case A_AHB2RSTR:
+        retvalue = s->ahb2rstr;
+        break;
+    case A_AHB3RSTR:
+        retvalue = s->ahb3rstr;
+        break;
+    case A_APB1RSTR1:
+        retvalue = s->apb1rstr1;
+        break;
+    case A_APB1RSTR2:
+        retvalue = s->apb1rstr2;
+        break;
+    case A_APB2RSTR:
+        retvalue = s->apb2rstr;
+        break;
+    case A_AHB1ENR:
+        retvalue = s->ahb1enr;
+        break;
+    case A_AHB2ENR:
+        retvalue = s->ahb2enr;
+        break;
+    case A_AHB3ENR:
+        retvalue = s->ahb3enr;
+        break;
+    case A_APB1ENR1:
+        retvalue = s->apb1enr1;
+        break;
+    case A_APB1ENR2:
+        retvalue = s->apb1enr2;
+        break;
+    case A_APB2ENR:
+        retvalue = s->apb2enr;
+        break;
+    case A_AHB1SMENR:
+        retvalue = s->ahb1smenr;
+        break;
+    case A_AHB2SMENR:
+        retvalue = s->ahb2smenr;
+        break;
+    case A_AHB3SMENR:
+        retvalue = s->ahb3smenr;
+        break;
+    case A_APB1SMENR1:
+        retvalue = s->apb1smenr1;
+        break;
+    case A_APB1SMENR2:
+        retvalue = s->apb1smenr2;
+        break;
+    case A_APB2SMENR:
+        retvalue = s->apb2smenr;
+        break;
+    case A_CCIPR:
+        retvalue = s->ccipr;
+        break;
+    case A_BDCR:
+        retvalue = s->bdcr;
+        break;
+    case A_CSR:
+        retvalue = s->csr;
+        break;
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: Bad offset 0x%"HWADDR_PRIx"\n", __func__, addr);
+        break;
+    }
+
+    trace_stm32l4x5_rcc_read(addr, retvalue);
+
+    return retvalue;
+}
+
+static void stm32l4x5_rcc_write(void *opaque, hwaddr addr,
+                                  uint64_t val64, unsigned int size)
+{
+    Stm32l4x5RccState *s = opaque;
+    const uint32_t value = val64;
+
+    trace_stm32l4x5_rcc_write(addr, value);
+
+    switch (addr) {
+    case A_CR:
+        s->cr = (s->cr & CR_READ_SET_MASK) |
+                (value & (CR_READ_SET_MASK | ~CR_READ_ONLY_MASK));
+        break;
+    case A_ICSCR:
+        s->icscr = value & ~ICSCR_READ_ONLY_MASK;
+        break;
+    case A_CFGR:
+        s->cfgr = value & ~CFGR_READ_ONLY_MASK;
+        break;
+    case A_PLLCFGR:
+        s->pllcfgr = value;
+        break;
+    case A_PLLSAI1CFGR:
+        s->pllsai1cfgr = value;
+        break;
+    case A_PLLSAI2CFGR:
+        s->pllsai2cfgr = value;
+        break;
+    case A_CIER:
+        s->cier = value;
+        break;
+    case A_CIFR:
+        qemu_log_mask(LOG_GUEST_ERROR,
+            "%s: Write attempt into read-only register (CIFR) 0x%"PRIx32"\n",
+            __func__, value);
+        break;
+    case A_CICR:
+        /* Clear interrupt flags by writing a 1 to the CICR register */
+        s->cifr &= ~value;
+        rcc_update_irq(s);
+        break;
+    /* Reset behaviors are not implemented */
+    case A_AHB1RSTR:
+        s->ahb1rstr = value;
+        break;
+    case A_AHB2RSTR:
+        s->ahb2rstr = value;
+        break;
+    case A_AHB3RSTR:
+        s->ahb3rstr = value;
+        break;
+    case A_APB1RSTR1:
+        s->apb1rstr1 = value;
+        break;
+    case A_APB1RSTR2:
+        s->apb1rstr2 = value;
+        break;
+    case A_APB2RSTR:
+        s->apb2rstr = value;
+        break;
+    case A_AHB1ENR:
+        s->ahb1enr = value;
+        break;
+    case A_AHB2ENR:
+        s->ahb2enr = value;
+        break;
+    case A_AHB3ENR:
+        s->ahb3enr = value;
+        break;
+    case A_APB1ENR1:
+        s->apb1enr1 = value;
+        break;
+    case A_APB1ENR2:
+        s->apb1enr2 = value;
+        break;
+    case A_APB2ENR:
+        s->apb2enr = (s->apb2enr & APB2ENR_READ_SET_MASK) | value;
+        break;
+    /* Behaviors for Sleep and Stop modes are not implemented */
+    case A_AHB1SMENR:
+        s->ahb1smenr = value;
+        break;
+    case A_AHB2SMENR:
+        s->ahb2smenr = value;
+        break;
+    case A_AHB3SMENR:
+        s->ahb3smenr = value;
+        break;
+    case A_APB1SMENR1:
+        s->apb1smenr1 = value;
+        break;
+    case A_APB1SMENR2:
+        s->apb1smenr2 = value;
+        break;
+    case A_APB2SMENR:
+        s->apb2smenr = value;
+        break;
+    case A_CCIPR:
+        s->ccipr = value;
+        break;
+    case A_BDCR:
+        s->bdcr = value & ~BDCR_READ_ONLY_MASK;
+        break;
+    case A_CSR:
+        s->csr = value & ~CSR_READ_ONLY_MASK;
+        break;
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: Bad offset 0x%"HWADDR_PRIx"\n", __func__, addr);
+    }
+}
+
+static const MemoryRegionOps stm32l4x5_rcc_ops = {
+    .read = stm32l4x5_rcc_read,
+    .write = stm32l4x5_rcc_write,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+    .valid = {
+        .max_access_size = 4,
+        .min_access_size = 4,
+        .unaligned = false
+    },
+    .impl = {
+        .max_access_size = 4,
+        .min_access_size = 4,
+        .unaligned = false
+    },
+};
+
+static const ClockPortInitArray stm32l4x5_rcc_clocks = {
+    QDEV_CLOCK_IN(Stm32l4x5RccState, hsi16_rc, NULL, 0),
+    QDEV_CLOCK_IN(Stm32l4x5RccState, msi_rc, NULL, 0),
+    QDEV_CLOCK_IN(Stm32l4x5RccState, hse, NULL, 0),
+    QDEV_CLOCK_IN(Stm32l4x5RccState, lsi_rc, NULL, 0),
+    QDEV_CLOCK_IN(Stm32l4x5RccState, lse_crystal, NULL, 0),
+    QDEV_CLOCK_IN(Stm32l4x5RccState, sai1_extclk, NULL, 0),
+    QDEV_CLOCK_IN(Stm32l4x5RccState, sai2_extclk, NULL, 0),
+    QDEV_CLOCK_END
+};
+
+
+static void stm32l4x5_rcc_init(Object *obj)
+{
+    Stm32l4x5RccState *s = STM32L4X5_RCC(obj);
+
+    sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->irq);
+
+    memory_region_init_io(&s->mmio, obj, &stm32l4x5_rcc_ops, s,
+                          TYPE_STM32L4X5_RCC, 0x400);
+    sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->mmio);
+
+    qdev_init_clocks(DEVICE(s), stm32l4x5_rcc_clocks);
+
+    s->gnd = clock_new(obj, "gnd");
+}
+
+static const VMStateDescription vmstate_stm32l4x5_rcc = {
+    .name = TYPE_STM32L4X5_RCC,
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT32(cr, Stm32l4x5RccState),
+        VMSTATE_UINT32(icscr, Stm32l4x5RccState),
+        VMSTATE_UINT32(cfgr, Stm32l4x5RccState),
+        VMSTATE_UINT32(pllcfgr, Stm32l4x5RccState),
+        VMSTATE_UINT32(pllsai1cfgr, Stm32l4x5RccState),
+        VMSTATE_UINT32(pllsai2cfgr, Stm32l4x5RccState),
+        VMSTATE_UINT32(cier, Stm32l4x5RccState),
+        VMSTATE_UINT32(cifr, Stm32l4x5RccState),
+        VMSTATE_UINT32(ahb1rstr, Stm32l4x5RccState),
+        VMSTATE_UINT32(ahb2rstr, Stm32l4x5RccState),
+        VMSTATE_UINT32(ahb3rstr, Stm32l4x5RccState),
+        VMSTATE_UINT32(apb1rstr1, Stm32l4x5RccState),
+        VMSTATE_UINT32(apb1rstr2, Stm32l4x5RccState),
+        VMSTATE_UINT32(apb2rstr, Stm32l4x5RccState),
+        VMSTATE_UINT32(ahb1enr, Stm32l4x5RccState),
+        VMSTATE_UINT32(ahb2enr, Stm32l4x5RccState),
+        VMSTATE_UINT32(ahb3enr, Stm32l4x5RccState),
+        VMSTATE_UINT32(apb1enr1, Stm32l4x5RccState),
+        VMSTATE_UINT32(apb1enr2, Stm32l4x5RccState),
+        VMSTATE_UINT32(apb2enr, Stm32l4x5RccState),
+        VMSTATE_UINT32(ahb1smenr, Stm32l4x5RccState),
+        VMSTATE_UINT32(ahb2smenr, Stm32l4x5RccState),
+        VMSTATE_UINT32(ahb3smenr, Stm32l4x5RccState),
+        VMSTATE_UINT32(apb1smenr1, Stm32l4x5RccState),
+        VMSTATE_UINT32(apb1smenr2, Stm32l4x5RccState),
+        VMSTATE_UINT32(apb2smenr, Stm32l4x5RccState),
+        VMSTATE_UINT32(ccipr, Stm32l4x5RccState),
+        VMSTATE_UINT32(bdcr, Stm32l4x5RccState),
+        VMSTATE_UINT32(csr, Stm32l4x5RccState),
+        VMSTATE_CLOCK(hsi16_rc, Stm32l4x5RccState),
+        VMSTATE_CLOCK(msi_rc, Stm32l4x5RccState),
+        VMSTATE_CLOCK(hse, Stm32l4x5RccState),
+        VMSTATE_CLOCK(lsi_rc, Stm32l4x5RccState),
+        VMSTATE_CLOCK(lse_crystal, Stm32l4x5RccState),
+        VMSTATE_CLOCK(sai1_extclk, Stm32l4x5RccState),
+        VMSTATE_CLOCK(sai2_extclk, Stm32l4x5RccState),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+
+static void stm32l4x5_rcc_realize(DeviceState *dev, Error **errp)
+{
+    Stm32l4x5RccState *s = STM32L4X5_RCC(dev);
+
+    if (s->hse_frequency <  4000000ULL ||
+        s->hse_frequency > 48000000ULL) {
+            error_setg(errp,
+                "HSE frequency is outside of the allowed [4-48]Mhz range: %" PRIx64 "",
+                s->hse_frequency);
+            return;
+        }
+
+    clock_update_hz(s->msi_rc, MSI_DEFAULT_FRQ);
+    clock_update_hz(s->sai1_extclk, s->sai1_extclk_frequency);
+    clock_update_hz(s->sai2_extclk, s->sai2_extclk_frequency);
+    clock_update(s->gnd, 0);
+}
+
+static Property stm32l4x5_rcc_properties[] = {
+    DEFINE_PROP_UINT64("hse_frequency", Stm32l4x5RccState,
+        hse_frequency, HSE_DEFAULT_FRQ),
+    DEFINE_PROP_UINT64("sai1_extclk_frequency", Stm32l4x5RccState,
+        sai1_extclk_frequency, 0),
+    DEFINE_PROP_UINT64("sai2_extclk_frequency", Stm32l4x5RccState,
+        sai2_extclk_frequency, 0),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static void stm32l4x5_rcc_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+    ResettableClass *rc = RESETTABLE_CLASS(klass);
+
+
+    rc->phases.hold = stm32l4x5_rcc_reset_hold;
+    device_class_set_props(dc, stm32l4x5_rcc_properties);
+    dc->realize = stm32l4x5_rcc_realize;
+    dc->vmsd = &vmstate_stm32l4x5_rcc;
+}
+
+static const TypeInfo stm32l4x5_rcc_types[] = {
+    {
+        .name           = TYPE_STM32L4X5_RCC,
+        .parent         = TYPE_SYS_BUS_DEVICE,
+        .instance_size  = sizeof(Stm32l4x5RccState),
+        .instance_init  = stm32l4x5_rcc_init,
+        .class_init     = stm32l4x5_rcc_class_init,
+    }
+};
+
+DEFINE_TYPES(stm32l4x5_rcc_types)
diff --git a/hw/misc/trace-events b/hw/misc/trace-events
index 5f5bc92222..38169ccbc1 100644
--- a/hw/misc/trace-events
+++ b/hw/misc/trace-events
@@ -174,6 +174,10 @@ stm32l4x5_exti_set_irq(int irq, int level) "Set EXTI: %d to %d"
 stm32l4x5_exti_read(uint64_t addr, uint64_t data) "reg read: addr: 0x%" PRIx64 " val: 0x%" PRIx64 ""
 stm32l4x5_exti_write(uint64_t addr, uint64_t data) "reg write: addr: 0x%" PRIx64 " val: 0x%" PRIx64 ""
 
+# stm32l4x5_rcc.c
+stm32l4x5_rcc_read(uint64_t addr, uint32_t data) "RCC: Read <0x%" PRIx64 "> -> 0x%" PRIx32
+stm32l4x5_rcc_write(uint64_t addr, uint32_t data) "RCC: Write <0x%" PRIx64 "> <- 0x%" PRIx32
+
 # tz-mpc.c
 tz_mpc_reg_read(uint32_t offset, uint64_t data, unsigned size) "TZ MPC regs read: offset 0x%x data 0x%" PRIx64 " size %u"
 tz_mpc_reg_write(uint32_t offset, uint64_t data, unsigned size) "TZ MPC regs write: offset 0x%x data 0x%" PRIx64 " size %u"