[Qemu-devel] [PATCH v2] armv7-m: exit on external reset request

[Michael Davidsaver]

Implement the SYSRESETREQ bit of the AIRCR register
for armv7-m (ie. cortex-m3) to trigger a GPIO out.

Change armv7m_init to return the DeviceState* for the NVIC.
This allows access to all GPIO blocks, not just the IRQ inputs.
Move qdev_get_gpio_in() calls out of armv7m_init() into
board code for stellaris and stm32f205 boards.

Add GPIO in for the stellaris board which calls
qemu_system_reset_request() on reset request.
---
 hw/arm/armv7m.c        |  9 ++-------
 hw/arm/stellaris.c     | 36 +++++++++++++++++++++++++-----------
 hw/arm/stm32f205_soc.c | 13 ++++++-------
 hw/intc/armv7m_nvic.c  |  7 ++++++-
 include/hw/arm/arm.h   |  2 +-
 5 files changed, 40 insertions(+), 27 deletions(-)

diff --git a/hw/arm/armv7m.c b/hw/arm/armv7m.c
index eb214db..a80d2ad 100644
--- a/hw/arm/armv7m.c
+++ b/hw/arm/armv7m.c
@@ -166,17 +166,15 @@ static void armv7m_reset(void *opaque)
    mem_size is in bytes.
    Returns the NVIC array.  */
 
-qemu_irq *armv7m_init(MemoryRegion *system_memory, int mem_size, int num_irq,
+DeviceState *armv7m_init(MemoryRegion *system_memory, int mem_size, int 
num_irq,
                       const char *kernel_filename, const char *cpu_model)
 {
     ARMCPU *cpu;
     CPUARMState *env;
     DeviceState *nvic;
-    qemu_irq *pic = g_new(qemu_irq, num_irq);
     int image_size;
     uint64_t entry;
     uint64_t lowaddr;
-    int i;
     int big_endian;
     MemoryRegion *hack = g_new(MemoryRegion, 1);
 
@@ -198,9 +196,6 @@ qemu_irq *armv7m_init(MemoryRegion *system_memory, int 
mem_size, int num_irq,
     qdev_init_nofail(nvic);
     sysbus_connect_irq(SYS_BUS_DEVICE(nvic), 0,
                        qdev_get_gpio_in(DEVICE(cpu), ARM_CPU_IRQ));
-    for (i = 0; i < num_irq; i++) {
-        pic[i] = qdev_get_gpio_in(nvic, i);
-    }
 
 #ifdef TARGET_WORDS_BIGENDIAN
     big_endian = 1;
@@ -234,7 +229,7 @@ qemu_irq *armv7m_init(MemoryRegion *system_memory, int 
mem_size, int num_irq,
     memory_region_add_subregion(system_memory, 0xfffff000, hack);
 
     qemu_register_reset(armv7m_reset, cpu);
-    return pic;
+    return nvic;
 }
 
 static Property bitband_properties[] = {
diff --git a/hw/arm/stellaris.c b/hw/arm/stellaris.c
index 3d6486f..e3b19f3 100644
--- a/hw/arm/stellaris.c
+++ b/hw/arm/stellaris.c
@@ -16,6 +16,7 @@
 #include "net/net.h"
 #include "hw/boards.h"
 #include "exec/address-spaces.h"
+#include "sysemu/sysemu.h"
 
 #define GPIO_A 0
 #define GPIO_B 1
@@ -1176,6 +1177,13 @@ static int stellaris_adc_init(SysBusDevice *sbd)
     return 0;
 }
 
+static
+void do_sys_reset(void *opaque, int n, int level)
+{
+    if(level)
+        qemu_system_reset_request();
+}
+
 /* Board init.  */
 static stellaris_board_info stellaris_boards[] = {
   { "LM3S811EVB",
@@ -1210,8 +1218,7 @@ static void stellaris_init(const char *kernel_filename, 
const char *cpu_model,
         0x40024000, 0x40025000, 0x40026000};
     static const int gpio_irq[7] = {0, 1, 2, 3, 4, 30, 31};
 
-    qemu_irq *pic;
-    DeviceState *gpio_dev[7];
+    DeviceState *gpio_dev[7], *nvic;
     qemu_irq gpio_in[7][8];
     qemu_irq gpio_out[7][8];
     qemu_irq adc;
@@ -1241,12 +1248,19 @@ static void stellaris_init(const char *kernel_filename, 
const char *cpu_model,
     vmstate_register_ram_global(sram);
     memory_region_add_subregion(system_memory, 0x20000000, sram);
 
-    pic = armv7m_init(system_memory, flash_size, NUM_IRQ_LINES,
+    nvic = armv7m_init(system_memory, flash_size, NUM_IRQ_LINES,
                       kernel_filename, cpu_model);
 
+    qdev_connect_gpio_out_named(nvic, "SYSRESETREQ", 0,
+                                qemu_allocate_irq(&do_sys_reset, NULL, 0));
+
     if (board->dc1 & (1 << 16)) {
         dev = sysbus_create_varargs(TYPE_STELLARIS_ADC, 0x40038000,
-                                    pic[14], pic[15], pic[16], pic[17], NULL);
+                                    qdev_get_gpio_in(nvic, 14),
+                                    qdev_get_gpio_in(nvic, 15),
+                                    qdev_get_gpio_in(nvic, 16),
+                                    qdev_get_gpio_in(nvic, 17),
+                                    NULL);
         adc = qdev_get_gpio_in(dev, 0);
     } else {
         adc = NULL;
@@ -1255,19 +1269,19 @@ static void stellaris_init(const char *kernel_filename, 
const char *cpu_model,
         if (board->dc2 & (0x10000 << i)) {
             dev = sysbus_create_simple(TYPE_STELLARIS_GPTM,
                                        0x40030000 + i * 0x1000,
-                                       pic[timer_irq[i]]);
+                                       qdev_get_gpio_in(nvic, timer_irq[i]));
             /* TODO: This is incorrect, but we get away with it because
                the ADC output is only ever pulsed.  */
             qdev_connect_gpio_out(dev, 0, adc);
         }
     }
 
-    stellaris_sys_init(0x400fe000, pic[28], board, nd_table[0].macaddr.a);
+    stellaris_sys_init(0x400fe000, qdev_get_gpio_in(nvic, 28), board, 
nd_table[0].macaddr.a);
 
     for (i = 0; i < 7; i++) {
         if (board->dc4 & (1 << i)) {
             gpio_dev[i] = sysbus_create_simple("pl061_luminary", gpio_addr[i],
-                                               pic[gpio_irq[i]]);
+                                               qdev_get_gpio_in(nvic, 
gpio_irq[i]));
             for (j = 0; j < 8; j++) {
                 gpio_in[i][j] = qdev_get_gpio_in(gpio_dev[i], j);
                 gpio_out[i][j] = NULL;
@@ -1276,7 +1290,7 @@ static void stellaris_init(const char *kernel_filename, 
const char *cpu_model,
     }
 
     if (board->dc2 & (1 << 12)) {
-        dev = sysbus_create_simple(TYPE_STELLARIS_I2C, 0x40020000, pic[8]);
+        dev = sysbus_create_simple(TYPE_STELLARIS_I2C, 0x40020000, 
qdev_get_gpio_in(nvic, 8));
         i2c = (I2CBus *)qdev_get_child_bus(dev, "i2c");
         if (board->peripherals & BP_OLED_I2C) {
             i2c_create_slave(i2c, "ssd0303", 0x3d);
@@ -1286,11 +1300,11 @@ static void stellaris_init(const char *kernel_filename, 
const char *cpu_model,
     for (i = 0; i < 4; i++) {
         if (board->dc2 & (1 << i)) {
             sysbus_create_simple("pl011_luminary", 0x4000c000 + i * 0x1000,
-                                 pic[uart_irq[i]]);
+                                 qdev_get_gpio_in(nvic, uart_irq[i]));
         }
     }
     if (board->dc2 & (1 << 4)) {
-        dev = sysbus_create_simple("pl022", 0x40008000, pic[7]);
+        dev = sysbus_create_simple("pl022", 0x40008000, qdev_get_gpio_in(nvic, 
7));
         if (board->peripherals & BP_OLED_SSI) {
             void *bus;
             DeviceState *sddev;
@@ -1326,7 +1340,7 @@ static void stellaris_init(const char *kernel_filename, 
const char *cpu_model,
         qdev_set_nic_properties(enet, &nd_table[0]);
         qdev_init_nofail(enet);
         sysbus_mmio_map(SYS_BUS_DEVICE(enet), 0, 0x40048000);
-        sysbus_connect_irq(SYS_BUS_DEVICE(enet), 0, pic[42]);
+        sysbus_connect_irq(SYS_BUS_DEVICE(enet), 0, qdev_get_gpio_in(nvic, 
42));
     }
     if (board->peripherals & BP_GAMEPAD) {
         qemu_irq gpad_irq[5];
diff --git a/hw/arm/stm32f205_soc.c b/hw/arm/stm32f205_soc.c
index 4d26a7e..b3e4c31 100644
--- a/hw/arm/stm32f205_soc.c
+++ b/hw/arm/stm32f205_soc.c
@@ -59,9 +59,8 @@ static void stm32f205_soc_initfn(Object *obj)
 static void stm32f205_soc_realize(DeviceState *dev_soc, Error **errp)
 {
     STM32F205State *s = STM32F205_SOC(dev_soc);
-    DeviceState *syscfgdev, *usartdev, *timerdev;
+    DeviceState *syscfgdev, *usartdev, *timerdev, *nvic;
     SysBusDevice *syscfgbusdev, *usartbusdev, *timerbusdev;
-    qemu_irq *pic;
     Error *err = NULL;
     int i;
 
@@ -88,8 +87,8 @@ static void stm32f205_soc_realize(DeviceState *dev_soc, Error 
**errp)
     vmstate_register_ram_global(sram);
     memory_region_add_subregion(system_memory, SRAM_BASE_ADDRESS, sram);
 
-    pic = armv7m_init(get_system_memory(), FLASH_SIZE, 96,
-                      s->kernel_filename, s->cpu_model);
+    nvic = armv7m_init(get_system_memory(), FLASH_SIZE, 96,
+                       s->kernel_filename, s->cpu_model);
 
     /* System configuration controller */
     syscfgdev = DEVICE(&s->syscfg);
@@ -100,7 +99,7 @@ static void stm32f205_soc_realize(DeviceState *dev_soc, 
Error **errp)
     }
     syscfgbusdev = SYS_BUS_DEVICE(syscfgdev);
     sysbus_mmio_map(syscfgbusdev, 0, 0x40013800);
-    sysbus_connect_irq(syscfgbusdev, 0, pic[71]);
+    sysbus_connect_irq(syscfgbusdev, 0, qdev_get_gpio_in(nvic, 71));
 
     /* Attach UART (uses USART registers) and USART controllers */
     for (i = 0; i < STM_NUM_USARTS; i++) {
@@ -112,7 +111,7 @@ static void stm32f205_soc_realize(DeviceState *dev_soc, 
Error **errp)
         }
         usartbusdev = SYS_BUS_DEVICE(usartdev);
         sysbus_mmio_map(usartbusdev, 0, usart_addr[i]);
-        sysbus_connect_irq(usartbusdev, 0, pic[usart_irq[i]]);
+        sysbus_connect_irq(usartbusdev, 0, qdev_get_gpio_in(nvic, 
usart_irq[i]));
     }
 
     /* Timer 2 to 5 */
@@ -126,7 +125,7 @@ static void stm32f205_soc_realize(DeviceState *dev_soc, 
Error **errp)
         }
         timerbusdev = SYS_BUS_DEVICE(timerdev);
         sysbus_mmio_map(timerbusdev, 0, timer_addr[i]);
-        sysbus_connect_irq(timerbusdev, 0, pic[timer_irq[i]]);
+        sysbus_connect_irq(timerbusdev, 0, qdev_get_gpio_in(nvic, 
timer_irq[i]));
     }
 }
 
diff --git a/hw/intc/armv7m_nvic.c b/hw/intc/armv7m_nvic.c
index 3ec8408..52990e9 100644
--- a/hw/intc/armv7m_nvic.c
+++ b/hw/intc/armv7m_nvic.c
@@ -28,6 +28,7 @@ typedef struct {
     MemoryRegion gic_iomem_alias;
     MemoryRegion container;
     uint32_t num_irq;
+    qemu_irq sysresetreq;
 } nvic_state;
 
 #define TYPE_NVIC "armv7m_nvic"
@@ -348,10 +349,13 @@ static void nvic_writel(nvic_state *s, uint32_t offset, 
uint32_t value)
         break;
     case 0xd0c: /* Application Interrupt/Reset Control.  */
         if ((value >> 16) == 0x05fa) {
+            if (value & 4) {
+                qemu_irq_pulse(s->sysresetreq);
+            }
             if (value & 2) {
                 qemu_log_mask(LOG_UNIMP, "VECTCLRACTIVE unimplemented\n");
             }
-            if (value & 5) {
+            if (value & 1) {
                 qemu_log_mask(LOG_UNIMP, "AIRCR system reset unimplemented\n");
             }
             if (value & 0x700) {
@@ -540,6 +544,7 @@ static void armv7m_nvic_instance_init(Object *obj)
      * set the num-irq property appropriately.
      */
     s->num_irq = 64;
+    qdev_init_gpio_out_named(DEVICE(obj), &NVIC(obj)->sysresetreq, 
"SYSRESETREQ", 1);
 }
 
 static void armv7m_nvic_class_init(ObjectClass *klass, void *data)
diff --git a/include/hw/arm/arm.h b/include/hw/arm/arm.h
index 4dcd4f9..7916b6b 100644
--- a/include/hw/arm/arm.h
+++ b/include/hw/arm/arm.h
@@ -17,7 +17,7 @@
 #include "cpu.h"
 
 /* armv7m.c */
-qemu_irq *armv7m_init(MemoryRegion *system_memory, int mem_size, int num_irq,
+DeviceState *armv7m_init(MemoryRegion *system_memory, int mem_size, int 
num_irq,
                       const char *kernel_filename, const char *cpu_model);
 
 /*
-- 
2.1.4