From 58361589d819c542be005744b80d24b6022b901f Mon Sep 17 00:00:00 2001
From: xiao <gaoro-xiao@foxmail.com>
Date: Wed, 29 Apr 2026 06:06:26 +0800
Subject: [PATCH] fix: defer ch390 exti until rtos is ready

---
 Core/Src/gpio.c                 | 10 ++++++++--
 Core/Src/stm32f1xx_it.c         |  8 ++++++--
 Drivers/CH390/CH390_Interface.c |  2 ++
 3 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/Core/Src/gpio.c b/Core/Src/gpio.c
index b53bd1f..c351fac 100644
--- a/Core/Src/gpio.c
+++ b/Core/Src/gpio.c
@@ -76,9 +76,15 @@ void MX_GPIO_Init(void)
   GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
   HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
 
-  /* EXTI interrupt init*/
+  /* EXTI interrupt init
+   * Keep CH390 INT masked during early boot.  PB0 may already be asserted at
+   * power-on, while the FreeRTOS semaphore is not created until
+   * MX_FREERTOS_Init().  The network driver enables EXTI0 after CH390 and the
+   * RTOS objects are ready.
+   */
+  HAL_NVIC_DisableIRQ(EXTI0_IRQn);
+  __HAL_GPIO_EXTI_CLEAR_IT(GPIO_PIN_0);
   HAL_NVIC_SetPriority(EXTI0_IRQn, 6, 0);
-  HAL_NVIC_EnableIRQ(EXTI0_IRQn);
 
 }
 
diff --git a/Core/Src/stm32f1xx_it.c b/Core/Src/stm32f1xx_it.c
index 5a83181..697aef5 100644
--- a/Core/Src/stm32f1xx_it.c
+++ b/Core/Src/stm32f1xx_it.c
@@ -2,6 +2,7 @@
 #include "stm32f1xx_it.h"
 
 #include "FreeRTOS.h"
+#include "semphr.h"
 #include "task.h"
 
 #include "app_runtime.h"
@@ -101,8 +102,11 @@ void EXTI0_IRQHandler(void)
 
     if (__HAL_GPIO_EXTI_GET_IT(GPIO_PIN_0) != RESET) {
         __HAL_GPIO_EXTI_CLEAR_IT(GPIO_PIN_0);
-        xSemaphoreGiveFromISR(xNetSemaphore, &xHigherPriorityTaskWoken);
-        portYIELD_FROM_ISR(xHigherPriorityTaskWoken);
+        if ((xNetSemaphore != NULL) &&
+            (xTaskGetSchedulerState() == taskSCHEDULER_RUNNING)) {
+            xSemaphoreGiveFromISR(xNetSemaphore, &xHigherPriorityTaskWoken);
+            portYIELD_FROM_ISR(xHigherPriorityTaskWoken);
+        }
     }
 }
 
diff --git a/Drivers/CH390/CH390_Interface.c b/Drivers/CH390/CH390_Interface.c
index 6e65e67..88ed4d5 100644
--- a/Drivers/CH390/CH390_Interface.c
+++ b/Drivers/CH390/CH390_Interface.c
@@ -188,6 +188,8 @@ void ch390_interrupt_init(void)
     /* EXTI0 is configured in CubeMX for PB0 */
     /* NVIC priority should be >= configLIBRARY_MAX_SYSCALL_INTERRUPT_PRIORITY */
     /* for FreeRTOS compatibility */
+    HAL_NVIC_DisableIRQ(EXTI0_IRQn);
+    __HAL_GPIO_EXTI_CLEAR_IT(CH390_INT_PIN);
     HAL_NVIC_SetPriority(EXTI0_IRQn, 6, 0);
     HAL_NVIC_EnableIRQ(EXTI0_IRQn);
 }