Qemu-STM32(五)：STM32F407加入USART控制器

概述

本文主要描述了在Qemu平台中，如何添加STM32F407的USART控制器模拟代码。

板子截图:

参考资料

STM32F4XX TRM手册，手册编号：RM0090

添加步骤

1、在hw/arm/Kconfig文件中添加STM32F4XX_USART，如下所示:

--- a/hw/arm/Kconfig
+++ b/hw/arm/Kconfig
@@ -338,6 +338,7 @@ config STM32F407_SOC
     select OR_IRQ
     select STM32F4XX_SYSCFG
     select STM32F4XX_EXTI
+    select STM32F4XX_USART

2、在include/hw/arm/stm32f407_soc.h文件中添加

--- a/include/hw/arm/stm32f407_soc.h
+++ b/include/hw/arm/stm32f407_soc.h
@@ -25,6 +25,7 @@
 #include "hw/arm/armv7m.h"
 #include "hw/misc/stm32f4xx_syscfg.h"
 #include "hw/misc/stm32f4xx_exti.h"
+#include "hw/char/stm32f4xx_usart.h"
 
 #define TYPE_STM32F407_SOC "stm32f407-soc"
 #define STM32F407_SOC(obj) \
@@ -35,6 +36,12 @@
 
 #define EXIT_BASE_ADDRESS 0x40013C00
 
+#define STM_NUM_USARTS      4
+#define STM32F407_USART1    0x40011000
+#define STM32F407_USART2    0x40004400
+#define STM32F407_USART3    0x40004800
+#define STM32F407_USART6    0x40011400
+
 #define FLASH_BASE_ADDRESS  0x8000000
 #define FLASH_SIZE          0x100000
 #define SRAM_BASE_ADDRESS   0x20000000
@@ -53,6 +60,7 @@ typedef struct STM32F407State {
 
     STM32F4xxSyscfgState syscfg;
     STM32F4xxExtiState exti;
+    STM32F4XXUsartState usart[STM_NUM_USARTS];
 } STM32F407State;

3、在hw/arm/stm32f407_soc.c文件中添加如下代码片段4.在hw/char/Kconfig中添加

--- a/hw/arm/stm32f407_soc.c
+++ b/hw/arm/stm32f407_soc.c
@@ -32,6 +32,15 @@
 #include "hw/arm/stm32f407_soc.h"
 #include "sysemu/sysemu.h"
 
+static const uint32_t usart_addr[STM_NUM_USARTS] = {
+    STM32F407_USART1, STM32F407_USART2, STM32F407_USART3,
+    STM32F407_USART6
+};
+
+static const int usart_irq[STM_NUM_USARTS] = {
+    37, 38, 39, 71
+};
+
 static const int exti_irq[] =
 {
     6, 7, 8, 9, 10, 23, 23, 23, 23, 23, 40,
@@ -42,6 +51,7 @@ static void stm32f407_soc_initfn(Object *obj)
 {
 
     STM32F407State *s = STM32F407_SOC(obj);
+    int i;
 
     sysbus_init_child_obj(obj, "armv7m", &s->armv7m, sizeof(s->armv7m),
                           TYPE_ARMV7M);
@@ -49,6 +59,11 @@ static void stm32f407_soc_initfn(Object *obj)
                           TYPE_STM32F4XX_SYSCFG);
     sysbus_init_child_obj(obj, "exti", &s->exti, sizeof(s->exti),
                           TYPE_STM32F4XX_EXTI);
+
+    for (i = 0; i < STM_NUM_USARTS; i++) {
+        object_initialize(&s->usart[i], sizeof(s->usart[i]), TYPE_STM32F4XX_USART);
+        qdev_set_parent_bus(DEVICE(&s->usart[i]), sysbus_get_default());
+    }
 }
 
 static void stm32f407_soc_realize(DeviceState *dev_soc, Error **errp)
@@ -95,6 +110,19 @@ static void stm32f407_soc_realize(DeviceState *dev_soc, Error **errp)
     for (i = 0; i < 16; i++) {
         qdev_connect_gpio_out(DEVICE(&s->syscfg), i, qdev_get_gpio_in(dev, i));
     }
+    /* USART controllers */
+    for (i = 0; i < STM_NUM_USARTS;