qemu-devel
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [RFC 1/1] Implement AVR watchdog timer


From: Pavel Dovgalyuk
Subject: Re: [RFC 1/1] Implement AVR watchdog timer
Date: Thu, 13 May 2021 15:27:53 +0300
User-agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.7.1

On 06.05.2021 00:18, Michael Rolnik wrote:
Signed-off-by: Michael Rolnik <mrolnik@gmail.com>
---
  MAINTAINERS                   |   2 +
  hw/avr/Kconfig                |   1 +
  hw/avr/atmega.c               |  15 +-
  hw/avr/atmega.h               |   2 +
  hw/watchdog/Kconfig           |   3 +
  hw/watchdog/avr_wdt.c         | 274 ++++++++++++++++++++++++++++++++++
  hw/watchdog/meson.build       |   2 +
  hw/watchdog/trace-events      |   5 +
  include/hw/watchdog/avr_wdt.h |  47 ++++++
  target/avr/cpu.c              |   3 +
  target/avr/cpu.h              |   1 +
  target/avr/helper.c           |   7 +-
  target/avr/translate.c        |  38 ++++-
  13 files changed, 391 insertions(+), 9 deletions(-)
  create mode 100644 hw/watchdog/avr_wdt.c
  create mode 100644 include/hw/watchdog/avr_wdt.h

diff --git a/MAINTAINERS b/MAINTAINERS
index 4c05ff8bba..e1fce736d2 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1052,6 +1052,8 @@ 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
+F: include/hw/watchdog/avr_wdt.h
+F: hw/watchdog/avr_wdt.c
Arduino
  M: Philippe Mathieu-Daudé <f4bug@amsat.org>
diff --git a/hw/avr/Kconfig b/hw/avr/Kconfig
index d31298c3cc..9939e4902f 100644
--- a/hw/avr/Kconfig
+++ b/hw/avr/Kconfig
@@ -3,6 +3,7 @@ config AVR_ATMEGA_MCU
      select AVR_TIMER16
      select AVR_USART
      select AVR_POWER
+    select AVR_WDT
config ARDUINO
      select AVR_ATMEGA_MCU
diff --git a/hw/avr/atmega.c b/hw/avr/atmega.c
index 44c6afebbb..31ceb1c21c 100644
--- a/hw/avr/atmega.c
+++ b/hw/avr/atmega.c
@@ -28,6 +28,7 @@ enum AtmegaPeripheral {
      GPIOG, GPIOH, GPIOI, GPIOJ, GPIOK, GPIOL,
      USART0, USART1, USART2, USART3,
      TIMER0, TIMER1, TIMER2, TIMER3, TIMER4, TIMER5,
+    WDT,
      PERIFMAX
  };
@@ -75,6 +76,7 @@ static const peripheral_cfg dev168_328[PERIFMAX] = {
      [GPIOD]         = {  0x29 },
      [GPIOC]         = {  0x26 },
      [GPIOB]         = {  0x23 },
+    [WDT]           = {  0x60 },
  }, dev1280_2560[PERIFMAX] = {
      [USART3]        = { 0x130, POWER1, 2 },
      [TIMER5]        = { 0x120, POWER1, 5, 0x73, 0x3a, true },
@@ -99,6 +101,7 @@ static const peripheral_cfg dev168_328[PERIFMAX] = {
      [GPIOC]         = {  0x26 },
      [GPIOB]         = {  0x23 },
      [GPIOA]         = {  0x20 },
+    [WDT]           = {  0x60 },
  };
enum AtmegaIrq {
@@ -118,6 +121,7 @@ enum AtmegaIrq {
          TIMER4_COMPC_IRQ, TIMER4_OVF_IRQ,
      TIMER5_CAPT_IRQ, TIMER5_COMPA_IRQ, TIMER5_COMPB_IRQ,
          TIMER5_COMPC_IRQ, TIMER5_OVF_IRQ,
+    WATCHDOG_TIMER_IRQ,
      IRQ_COUNT
  };
@@ -133,6 +137,7 @@ enum AtmegaIrq {
  #define TIMER_OVF_IRQ(n)    (n * TIMER_IRQ_COUNT + TIMER0_OVF_IRQ)
static const uint8_t irq168_328[IRQ_COUNT] = {
+    [WATCHDOG_TIMER_IRQ]    = 7,
      [TIMER2_COMPA_IRQ]      = 8,
      [TIMER2_COMPB_IRQ]      = 9,
      [TIMER2_OVF_IRQ]        = 10,
@@ -147,6 +152,7 @@ static const uint8_t irq168_328[IRQ_COUNT] = {
      [USART0_DRE_IRQ]        = 20,
      [USART0_TXC_IRQ]        = 21,
  }, irq1280_2560[IRQ_COUNT] = {
+    [WATCHDOG_TIMER_IRQ]    = 13,
      [TIMER2_COMPA_IRQ]      = 14,
      [TIMER2_COMPB_IRQ]      = 15,
      [TIMER2_OVF_IRQ]        = 16,
@@ -344,10 +350,17 @@ static void atmega_realize(DeviceState *dev, Error **errp)
          g_free(devname);
      }
+ /* Watchdog Timer */
+    object_initialize_child(OBJECT(dev), "wdt", &s->wdt, TYPE_AVR_WDT);
+    sysbus_realize(SYS_BUS_DEVICE(&s->wdt), &error_abort);
+    sysbus_mmio_map(SYS_BUS_DEVICE(&s->wdt), 0,
+                    OFFSET_DATA + mc->dev[WDT].addr);
+    qdev_connect_gpio_out_named(cpudev, "wdr", 0,
+                    qdev_get_gpio_in_named(DEVICE(&s->wdt), "wdr", 0));
+
      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);
  }
diff --git a/hw/avr/atmega.h b/hw/avr/atmega.h
index a99ee15c7e..60bbd44bdd 100644
--- a/hw/avr/atmega.h
+++ b/hw/avr/atmega.h
@@ -13,6 +13,7 @@
#include "hw/char/avr_usart.h"
  #include "hw/timer/avr_timer16.h"
+#include "hw/watchdog/avr_wdt.h"
  #include "hw/misc/avr_power.h"
  #include "target/avr/cpu.h"
  #include "qom/object.h"
@@ -45,6 +46,7 @@ struct AtmegaMcuState {
      AVRMaskState pwr[POWER_MAX];
      AVRUsartState usart[USART_MAX];
      AVRTimer16State timer[TIMER_MAX];
+    AVRWatchdogState wdt;
      uint64_t xtal_freq_hz;
  };
diff --git a/hw/watchdog/Kconfig b/hw/watchdog/Kconfig
index 66e1d029e3..e0f89d2fe0 100644
--- a/hw/watchdog/Kconfig
+++ b/hw/watchdog/Kconfig
@@ -20,3 +20,6 @@ config WDT_IMX2
config WDT_SBSA
      bool
+
+config AVR_WDT
+    bool
diff --git a/hw/watchdog/avr_wdt.c b/hw/watchdog/avr_wdt.c
new file mode 100644
index 0000000000..cbd6457c8b
--- /dev/null
+++ b/hw/watchdog/avr_wdt.c
@@ -0,0 +1,274 @@
+/*
+ * AVR watchdog
+ *
+ * Copyright (c) 2021 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/log.h"
+#include "hw/irq.h"
+#include "hw/watchdog/avr_wdt.h"
+#include "trace.h"
+#include "target/avr/cpu.h"
+#include "sysemu/runstate.h"
+
+/* Field masks */
+#define WDTCSR_MASK_WDP0    0x01
+#define WDTCSR_MASK_WDP1    0x02
+#define WDTCSR_MASK_WDP2    0x04
+#define WDTCSR_MASK_WDE     0x08
+#define WDTCSR_MASK_WDCE    0x10
+#define WDTCSR_MASK_WDP3    0x20
+#define WDTCSR_MASK_WDIE    0x40
+#define WDTCSR_MASK_WDIF    0x80
+
+#define WDTCSR_SHFT_WDP0    0x00
+#define WDTCSR_SHFT_WDP1    0x01
+#define WDTCSR_SHFT_WDP2    0x02
+#define WDTCSR_SHFT_WDE     0x03
+#define WDTCSR_SHFT_WDCE    0x04
+#define WDTCSR_SHFT_WDP3    0x05
+#define WDTCSR_SHFT_WDIE    0x06
+#define WDTCSR_SHFT_WDIF    0x07
+
+#define MCUSR_MASK_WDRF     0x04
+#define MCUSR_ADDR      (OFFSET_DATA + 0x55)
+
+/* Helper macros */
+#define WDP0(csr)       ((csr & WDTCSR_MASK_WDP0) >> WDTCSR_SHFT_WDP0)
+#define WDP1(csr)       ((csr & WDTCSR_MASK_WDP1) >> WDTCSR_SHFT_WDP1)
+#define WDP2(csr)       ((csr & WDTCSR_MASK_WDP2) >> WDTCSR_SHFT_WDP2)
+#define WDP3(csr)       ((csr & WDTCSR_MASK_WDP3) >> WDTCSR_SHFT_WDP3)
+#define WDP(csr)        ((WDP3(csr) << 3) | (WDP2(csr) << 2) | \
+                         (WDP1(csr) << 1) | (WDP0(csr) << 0))
+#define WDIE(csr)       ((csr & WDTCSR_MASK_WDIE) >> WDTCSR_SHFT_WDIE)
+#define WDE(csr)        ((csr & WDTCSR_MASK_WDE) >> WDTCSR_SHFT_WDE)
+#define WCE(csr)        ((csr & WDTCSR_MASK_WCE) >> WDTCSR_SHFT_WCE)
+
+#define DB_PRINT(fmt, args...) /* Nothing */
+
+#define MS2NS(n)        ((n) * 1000000ull)

I think there is SCALE_MS define for that.

+
+static void set_bits(uint8_t *addr, uint8_t bits)
+{
+    *addr |= bits;
+}
+
+static void rst_bits(uint8_t *addr, uint8_t bits)
+{
+    *addr &= ~bits;
+}
+
+static void avr_wdt_reset_alarm(AVRWatchdogState *wdt)
+{
+    uint32_t csr = wdt->csr;
+    int wdp = WDP(csr);
+
+    if (WDIE(csr) == 0 && WDE(csr) == 0) {
+        /* watchdog is stopped */
+        return;
+    }
+
+    timer_mod_ns(wdt->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
+            (MS2NS(15) << wdp));
+}
+
+static void avr_wdt_interrupt(void *opaque)
+{
+    AVRWatchdogState *wdt = opaque;
+    int8_t csr = wdt->csr;
+
+    if (WDIE(csr) == 1) {
+        /* Interrupt Mode */
+        set_bits(&wdt->csr, WDTCSR_MASK_WDIF);
+        qemu_set_irq(wdt->irq, 1);
+        trace_avr_wdt_interrupt();
+        rst_bits(&wdt->csr, WDTCSR_MASK_WDIF | WDTCSR_MASK_WDIE);
+    }
+
+    if (WDE(csr) == 1) {
+        /* System Reset Mode */
+        qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
+    }
+
+    avr_wdt_reset_alarm(wdt);
+}
+
+static void avr_wdt_reset(DeviceState *dev)
+{
+    AVRWatchdogState *wdt = AVR_WDT(dev);
+
+    wdt->csr = 0;
+    qemu_set_irq(wdt->irq, 0);
+    avr_wdt_reset_alarm(wdt);
+}
+
+static uint64_t avr_wdt_read(void *opaque, hwaddr offset, unsigned size)
+{
+    assert(size == 1);
+    AVRWatchdogState *wdt = opaque;
+    uint8_t retval = wdt->csr;
+
+    trace_avr_wdt_read(offset, retval);
+
+    return (uint64_t)retval;
+}
+
+static void avr_wdt_write(void *opaque, hwaddr offset,
+                              uint64_t val64, unsigned size)
+{
+    assert(size == 1);
+    AVRWatchdogState *wdt = opaque;
+    uint8_t val = (uint8_t)val64;
+    uint8_t set1 = val; /* bits that should be set to 1 */
+    uint8_t set0 = ~val;/* bits that should be set to 0 */
+    uint8_t mcusr = 0;
+
+    /*
+     *  Bit 7 - WDIF: Watchdog Interrupt Flag
+     *  This bit is set when a time-out occurs in the Watchdog Timer and the
+     *  Watchdog Timer is configured for interrupt. WDIF is cleared by hardware
+     *  when executing the corresponding interrupt handling vector.
+     *  Alternatively, WDIF is cleared by writing a logic one to the flag.
+     *  When the I-bit in SREG and WDIE are set, the Watchdog Time-out 
Interrupt
+     *  is executed.
+     */
+    if (val & WDTCSR_MASK_WDIF) {
+        rst_bits(&set1, WDTCSR_MASK_WDIF);  /* don't set 1 */
+        set_bits(&set0, WDTCSR_MASK_WDIF);  /* set 0 */
+    } else {
+        rst_bits(&set1, WDTCSR_MASK_WDIF);  /* don't set 1 */
+        rst_bits(&set0, WDTCSR_MASK_WDIF);  /* don't set 0 */
+    }
+
+    /*
+     *  Bit 4 - WDCE: Watchdog Change Enable
+     *  This bit is used in timed sequences for changing WDE and prescaler
+     *  bits. To clear the WDE bit, and/or change the prescaler bits,
+     *  WDCE must be set.
+     *  Once written to one, hardware will clear WDCE after four clock cycles.
+     */
+    if (!(val & WDTCSR_MASK_WDCE)) {
+        uint8_t bits = WDTCSR_MASK_WDE | WDTCSR_MASK_WDP0 | WDTCSR_MASK_WDP1 |
+                       WDTCSR_MASK_WDP2 | WDTCSR_MASK_WDP3;
+        rst_bits(&set1, bits);
+        rst_bits(&set0, bits);
+    }
+
+    /*
+     *  Bit 3 - WDE: Watchdog System Reset Enable
+     *  WDE is overridden by WDRF in MCUSR. This means that WDE is always set
+     *  when WDRF is set. To clear WDE, WDRF must be cleared first. This
+     *  feature ensures multiple resets during conditions causing failure, and
+     *  a safe start-up after the failure.
+     */
+    cpu_physical_memory_read(MCUSR_ADDR, &mcusr, sizeof(mcusr));
+    if (mcusr & MCUSR_MASK_WDRF) {
+        set_bits(&set1, WDTCSR_MASK_WDE);
+        rst_bits(&set0, WDTCSR_MASK_WDE);
+    }
+
+    /*  update CSR value */
+    assert((set0 & set1) == 0);
+
+    val = wdt->csr;
+    set_bits(&val, set1);
+    rst_bits(&val, set0);
+    wdt->csr = val;
+    trace_avr_wdt_write(offset, val);
+    avr_wdt_reset_alarm(wdt);
+
+    /*
+     *  Bit 6 - WDIE: Watchdog Interrupt Enable
+     *  When this bit is written to one and the I-bit in the Status Register is
+     *  set, the Watchdog Interrupt is enabled. If WDE is cleared in
+     *  combination with this setting, the Watchdog Timer is in Interrupt Mode,
+     *  and the corresponding interrupt is executed if time-out in the Watchdog
+     *  Timer occurs.
+     *  If WDE is set, the Watchdog Timer is in Interrupt and System Reset 
Mode.
+     *  The first time-out in the Watchdog Timer will set WDIF. Executing the
+     *  corresponding interrupt vector will clear WDIE and WDIF automatically 
by
+     *  hardware (the Watchdog goes to System Reset Mode). This is useful for
+     *  keeping the Watchdog Timer security while using the interrupt. To stay
+     *  in Interrupt and System Reset Mode, WDIE must be set after each
+     *  interrupt. This should however not be done within the interrupt service
+     *  routine itself, as this might compromise the safety-function of the
+     *  Watchdog System Reset mode. If the interrupt is not executed before the
+     *  next time-out, a System Reset will be applied.
+     */
+    if ((val & WDTCSR_MASK_WDIE) && (wdt->csr & WDTCSR_MASK_WDIF)) {
+        avr_wdt_interrupt(opaque);
+    }
+}
+
+static const MemoryRegionOps avr_wdt_ops = {
+    .read = avr_wdt_read,
+    .write = avr_wdt_write,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+    .impl = {.max_access_size = 1}
+};
+
+static void avr_wdt_wdr(void *opaque, int irq, int level)
+{
+    AVRWatchdogState *wdt = AVR_WDT(opaque);
+
+    avr_wdt_reset_alarm(wdt);
+}
+
+static void avr_wdt_init(Object *obj)
+{
+    AVRWatchdogState *s = AVR_WDT(obj);
+
+    sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->irq);
+
+    memory_region_init_io(&s->iomem, obj, &avr_wdt_ops,
+                          s, "avr-wdt", 0xa);
+
+    sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->iomem);
+    qdev_init_gpio_in_named(DEVICE(s), avr_wdt_wdr, "wdr", 1);
+}
+
+static void avr_wdt_realize(DeviceState *dev, Error **errp)
+{
+    AVRWatchdogState *s = AVR_WDT(dev);
+
+    s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, avr_wdt_interrupt, s);
+}
+
+static void avr_wdt_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->reset = avr_wdt_reset;
+    dc->realize = avr_wdt_realize;
+}
+
+static const TypeInfo avr_wdt_info = {
+    .name          = TYPE_AVR_WDT,
+    .parent        = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(AVRWatchdogState),
+    .instance_init = avr_wdt_init,
+    .class_init    = avr_wdt_class_init,
+};
+
+static void avr_wdt_register_types(void)
+{
+    type_register_static(&avr_wdt_info);
+}
+
+type_init(avr_wdt_register_types)
diff --git a/hw/watchdog/meson.build b/hw/watchdog/meson.build
index 054c403dea..8db2be8317 100644
--- a/hw/watchdog/meson.build
+++ b/hw/watchdog/meson.build
@@ -6,3 +6,5 @@ softmmu_ss.add(when: 'CONFIG_WDT_DIAG288', if_true: 
files('wdt_diag288.c'))
  softmmu_ss.add(when: 'CONFIG_ASPEED_SOC', if_true: files('wdt_aspeed.c'))
  softmmu_ss.add(when: 'CONFIG_WDT_IMX2', if_true: files('wdt_imx2.c'))
  softmmu_ss.add(when: 'CONFIG_WDT_SBSA', if_true: files('sbsa_gwdt.c'))
+
+specific_ss.add(when: 'CONFIG_AVR_WDT', if_true: files('avr_wdt.c'))
diff --git a/hw/watchdog/trace-events b/hw/watchdog/trace-events
index 3124ca1f1b..ac14773179 100644
--- a/hw/watchdog/trace-events
+++ b/hw/watchdog/trace-events
@@ -5,3 +5,8 @@ cmsdk_apb_watchdog_read(uint64_t offset, uint64_t data, unsigned 
size) "CMSDK AP
  cmsdk_apb_watchdog_write(uint64_t offset, uint64_t data, unsigned size) "CMSDK APB watchdog write: 
offset 0x%" PRIx64 " data 0x%" PRIx64 " size %u"
  cmsdk_apb_watchdog_reset(void) "CMSDK APB watchdog: reset"
  cmsdk_apb_watchdog_lock(uint32_t lock) "CMSDK APB watchdog: lock %" PRIu32
+
+# avr_wdt.c
+avr_wdt_read(uint8_t addr, uint8_t value) "wdt read addr:%u value:%u"
+avr_wdt_write(uint8_t addr, uint8_t value) "wdt write addr:%u value:%u"
+avr_wdt_interrupt(void) ""
diff --git a/include/hw/watchdog/avr_wdt.h b/include/hw/watchdog/avr_wdt.h
new file mode 100644
index 0000000000..8433663013
--- /dev/null
+++ b/include/hw/watchdog/avr_wdt.h
@@ -0,0 +1,47 @@
+/*
+ * AVR watchdog
+ *
+ * Copyright (c) 2021 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 HW_WATCHDOG_AVR_WDT_H
+#define HW_WATCHDOG_AVR_WDT_H
+
+#include "hw/sysbus.h"
+#include "qemu/timer.h"
+#include "hw/hw.h"
+#include "qom/object.h"
+
+#define TYPE_AVR_WDT "avr-wdt"
+OBJECT_DECLARE_SIMPLE_TYPE(AVRWatchdogState, AVR_WDT)
+
+struct AVRWatchdogState {
+    /* <private> */
+    SysBusDevice parent_obj;
+
+    /* <public> */
+    MemoryRegion iomem;
+    MemoryRegion imsk_iomem;
+    MemoryRegion ifr_iomem;
+    QEMUTimer *timer;
+    qemu_irq irq;
+
+    /* registers */
+    uint8_t csr;
+};
+

You should add vmstate which includes timer and csr. It will allow reverse debugging available with icount enabled.

+#endif /* HW_WATCHDOG_AVR_WDT_H */
diff --git a/target/avr/cpu.c b/target/avr/cpu.c
index 0f4596932b..d5eb785833 100644
--- a/target/avr/cpu.c
+++ b/target/avr/cpu.c
@@ -131,6 +131,9 @@ static void avr_cpu_initfn(Object *obj)
      /* Set the number of interrupts supported by the CPU. */
      qdev_init_gpio_in(DEVICE(cpu), avr_cpu_set_int,
                        sizeof(cpu->env.intsrc) * 8);
+
+    /* register watchdog timer reset interrupt */
+    qdev_init_gpio_out_named(DEVICE(cpu), &cpu->wdr, "wdr", 1);
  }
static ObjectClass *avr_cpu_class_by_name(const char *cpu_model)
diff --git a/target/avr/cpu.h b/target/avr/cpu.h
index d148e8c75a..f8f5641c8b 100644
--- a/target/avr/cpu.h
+++ b/target/avr/cpu.h
@@ -152,6 +152,7 @@ typedef struct AVRCPU {
CPUNegativeOffsetState neg;
      CPUAVRState env;
+    qemu_irq wdr; /* reset WDT */
  } AVRCPU;
extern const struct VMStateDescription vms_avr_cpu;
diff --git a/target/avr/helper.c b/target/avr/helper.c
index 35e1019594..dd88057e5f 100644
--- a/target/avr/helper.c
+++ b/target/avr/helper.c
@@ -24,6 +24,7 @@
  #include "exec/exec-all.h"
  #include "exec/address-spaces.h"
  #include "exec/helper-proto.h"
+#include "hw/irq.h"
bool avr_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
  {
@@ -188,11 +189,9 @@ void helper_break(CPUAVRState *env)
void helper_wdr(CPUAVRState *env)
  {
-    CPUState *cs = env_cpu(env);
+    AVRCPU *cpu = env_archcpu(env);
- /* WD is not implemented yet, placeholder */
-    cs->exception_index = EXCP_DEBUG;
-    cpu_loop_exit(cs);
+    qemu_set_irq(cpu->wdr, 1);
  }
/*
diff --git a/target/avr/translate.c b/target/avr/translate.c
index 850c5941d9..b7b716f4a0 100644
--- a/target/avr/translate.c
+++ b/target/avr/translate.c
@@ -1411,6 +1411,9 @@ static bool trans_SBIC(DisasContext *ctx, arg_SBIC *a)
  {
      TCGv temp = tcg_const_i32(a->reg);
+ if (tb_cflags(ctx->tb) & CF_USE_ICOUNT) {
+        gen_io_start();
+    }
      gen_helper_inb(temp, cpu_env, temp);
      tcg_gen_andi_tl(temp, temp, 1 << a->bit);
      ctx->skip_cond = TCG_COND_EQ;

Translation should stop at inb-related instructions in icount mode, because icount is valid only at the end of the block. Reading it in the middle makes execution non-deterministic.

@@ -1429,6 +1432,9 @@ static bool trans_SBIS(DisasContext *ctx, arg_SBIS *a)
  {
      TCGv temp = tcg_const_i32(a->reg);
+ if (tb_cflags(ctx->tb) & CF_USE_ICOUNT) {
+        gen_io_start();
+    }
      gen_helper_inb(temp, cpu_env, temp);
      tcg_gen_andi_tl(temp, temp, 1 << a->bit);
      ctx->skip_cond = TCG_COND_NE;
@@ -1611,6 +1617,9 @@ static TCGv gen_get_zaddr(void)
  static void gen_data_store(DisasContext *ctx, TCGv data, TCGv addr)
  {
      if (ctx->tb->flags & TB_FLAGS_FULL_ACCESS) {
+        if (tb_cflags(ctx->tb) & CF_USE_ICOUNT) {
+            gen_io_start();
+        }
          gen_helper_fullwr(cpu_env, data, addr);
      } else {
          tcg_gen_qemu_st8(data, addr, MMU_DATA_IDX); /* mem[addr] = data */
@@ -1620,6 +1629,9 @@ static void gen_data_store(DisasContext *ctx, TCGv data, 
TCGv addr)
  static void gen_data_load(DisasContext *ctx, TCGv data, TCGv addr)
  {
      if (ctx->tb->flags & TB_FLAGS_FULL_ACCESS) {
+        if (tb_cflags(ctx->tb) & CF_USE_ICOUNT) {
+            gen_io_start();
+        }
          gen_helper_fullrd(data, cpu_env, addr);
      } else {
          tcg_gen_qemu_ld8u(data, addr, MMU_DATA_IDX); /* data = mem[addr] */
@@ -2325,6 +2337,9 @@ static bool trans_IN(DisasContext *ctx, arg_IN *a)
      TCGv Rd = cpu_r[a->rd];
      TCGv port = tcg_const_i32(a->imm);
+ if (tb_cflags(ctx->tb) & CF_USE_ICOUNT) {
+        gen_io_start();
+    }
      gen_helper_inb(Rd, cpu_env, port);
tcg_temp_free_i32(port);
@@ -2341,6 +2356,9 @@ static bool trans_OUT(DisasContext *ctx, arg_OUT *a)
      TCGv Rd = cpu_r[a->rd];
      TCGv port = tcg_const_i32(a->imm);
+ if (tb_cflags(ctx->tb) & CF_USE_ICOUNT) {
+        gen_io_start();
+    }
      gen_helper_outb(cpu_env, port, Rd);
tcg_temp_free_i32(port);
@@ -2641,6 +2659,9 @@ static bool trans_SBI(DisasContext *ctx, arg_SBI *a)
      TCGv data = tcg_temp_new_i32();
      TCGv port = tcg_const_i32(a->reg);
+ if (tb_cflags(ctx->tb) & CF_USE_ICOUNT) {
+        gen_io_start();
+    }
      gen_helper_inb(data, cpu_env, port);
      tcg_gen_ori_tl(data, data, 1 << a->bit);
      gen_helper_outb(cpu_env, port, data);
@@ -2660,6 +2681,9 @@ static bool trans_CBI(DisasContext *ctx, arg_CBI *a)
      TCGv data = tcg_temp_new_i32();
      TCGv port = tcg_const_i32(a->reg);
+ if (tb_cflags(ctx->tb) & CF_USE_ICOUNT) {
+        gen_io_start();
+    }
      gen_helper_inb(data, cpu_env, port);
      tcg_gen_andi_tl(data, data, ~(1 << a->bit));
      gen_helper_outb(cpu_env, port, data);
@@ -2830,6 +2854,9 @@ static bool trans_SLEEP(DisasContext *ctx, arg_SLEEP *a)
   */
  static bool trans_WDR(DisasContext *ctx, arg_WDR *a)
  {
+    if (tb_cflags(ctx->tb) & CF_USE_ICOUNT) {
+        gen_io_start();
+    }
      gen_helper_wdr(cpu_env);
return true;
@@ -2919,6 +2946,9 @@ void gen_intermediate_code(CPUState *cs, TranslationBlock 
*tb, int max_insns)
           * This flag is set by ST/LD instruction we will regenerate it ONLY
           * with mem/cpu memory access instead of mem access
           */
+        if (tb_cflags(tb) & CF_USE_ICOUNT) {
+            gen_io_start();
+        }
          max_insns = 1;
      }
      if (ctx.singlestep) {
@@ -2955,6 +2985,10 @@ void gen_intermediate_code(CPUState *cs, 
TranslationBlock *tb, int max_insns)
              goto done_generating;
          }
+ if (num_insns == max_insns && (tb_cflags(tb) & CF_LAST_IO)) {
+            gen_io_start();
+        }
+
          /* Conditionally skip the next instruction, if indicated.  */
          if (ctx.skip_cond != TCG_COND_NEVER) {
              skip_label = gen_new_label();
@@ -2998,10 +3032,6 @@ void gen_intermediate_code(CPUState *cs, 
TranslationBlock *tb, int 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) {





reply via email to

[Prev in Thread] Current Thread [Next in Thread]