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/**
******************************************************************************
* @file Cortex/CORTEXM_ProcessStack/Src/main.c
* @author MCD Application Team
* @brief Description of the Cortex-M4 Mode Privilege example.
******************************************************************************
* @attention
*
* Copyright (c) 2017 STMicroelectronics.
* All rights reserved.
*
* This software is licensed under terms that can be found in the LICENSE file
* in the root directory of this software component.
* If no LICENSE file comes with this software, it is provided AS-IS.
*
******************************************************************************
*/
/* Includes ------------------------------------------------------------------*/
#include "main.h"
/** @addtogroup STM32F4xx_HAL_Examples
* @{
*/
/** @addtogroup CORTEXM_ProcessStack
* @{
*/
/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
#define SP_PROCESS_SIZE 0x200 /* Process stack size */
#define SP_PROCESS 0x02 /* Process stack */
#define SP_MAIN 0x00 /* Main stack */
/* Private function prototypes -----------------------------------------------*/
static __INLINE void __SVC(void);
/* Private macro -------------------------------------------------------------*/
#if defined ( __CC_ARM )
__ASM void __SVC(void)
{
SVC 0x01
BX R14
}
#elif defined ( __ICCARM__ )
static __INLINE void __SVC()
{
__ASM("svc 0x01");
}
#elif defined ( __GNUC__ )
static __INLINE void __SVC()
{
__ASM volatile("svc 0x01");
}
#elif defined ( __TASKING__ )
static __INLINE void __SVC()
{
__ASM("svc 0x01");
}
#endif
/* Private variables ---------------------------------------------------------*/
__IO uint8_t PSPMemAlloc[SP_PROCESS_SIZE];
__IO uint32_t Index = 0, PSPValue = 0, CurrentStack = 0, IsrStack = 0xFF;
/* Private function prototypes -----------------------------------------------*/
static void SystemClock_Config(void);
static void Error_Handler(void);
/* Private functions ---------------------------------------------------------*/
/**
* @brief Main program.
* @param None
* @retval None
*/
int main(void)
{
/* STM32F4xx HAL library initialization:
- Configure the Flash prefetch
- Systick timer is configured by default as source of time base, but user
can eventually implement his proper time base source (a general purpose
timer for example or other time source), keeping in mind that Time base
duration should be kept 1ms since PPP_TIMEOUT_VALUEs are defined and
handled in milliseconds basis.
- Set NVIC Group Priority to 4
- Low Level Initialization
*/
HAL_Init();
/* Configure the system clock to 100 MHz */
SystemClock_Config();
/* Configure LED1*/
BSP_LED_Init(LED1);
/* Configure LED3*/
BSP_LED_Init(LED3);
/* Switch Thread mode Stack from Main to Process -----------------------------*/
/* Initialize memory reserved for Process Stack */
for(Index = 0; Index < SP_PROCESS_SIZE; Index++)
{
PSPMemAlloc[Index] = 0x00;
}
/* Set Process stack value */
__set_PSP((uint32_t)PSPMemAlloc + SP_PROCESS_SIZE);
/* Select Process Stack as Thread mode Stack */
__set_CONTROL(SP_PROCESS);
/* Execute ISB instruction to flush pipeline as recommended by Arm */
__ISB();
/* Get the Thread mode stack used */
CurrentStack = (__get_CONTROL() & 0x02);
/* Get process stack pointer value */
PSPValue = __get_PSP();
/* Check is mode has been well applied */
if(CurrentStack != SP_PROCESS)
{
Error_Handler();
}
/* Generate a system call exception: Main Stack pointer should be automaticcaly
when entering in ISR context */
__SVC();
/* Check is Main stack was used under ISR*/
if(IsrStack != SP_MAIN)
{
Error_Handler();
}
/* Get the Thread mode stack used to verify we have switched back automatically
to Process Stack */
CurrentStack = (__get_CONTROL() & 0x02);
/* Check is mode has been well applied */
if(CurrentStack != SP_PROCESS)
{
Error_Handler();
}
else
{
/* Turn LED1 On*/
BSP_LED_On(LED1);
}
/* Infinite loop */
while (1)
{
}
}
/**
* @brief System Clock Configuration
* The system Clock is configured as follow :
* System Clock source = PLL (HSE)
* SYSCLK(Hz) = 100000000
* HCLK(Hz) = 100000000
* AHB Prescaler = 1
* APB1 Prescaler = 2
* APB2 Prescaler = 1
* HSE Frequency(Hz) = 8000000
* PLL_M = 8
* PLL_N = 200
* PLL_P = 2
* PLL_Q = 7
* PLL_R = 2
* VDD(V) = 3.3
* Main regulator output voltage = Scale1 mode
* Flash Latency(WS) = 3
* @param None
* @retval None
*/
static void SystemClock_Config(void)
{
RCC_ClkInitTypeDef RCC_ClkInitStruct;
RCC_OscInitTypeDef RCC_OscInitStruct;
HAL_StatusTypeDef ret = HAL_OK;
/* Enable Power Control clock */
__HAL_RCC_PWR_CLK_ENABLE();
/* The voltage scaling allows optimizing the power consumption when the device is
clocked below the maximum system frequency, to update the voltage scaling value
regarding system frequency refer to product datasheet. */
__HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);
/* Enable HSE Oscillator and activate PLL with HSE as source */
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
RCC_OscInitStruct.HSEState = RCC_HSE_BYPASS;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
RCC_OscInitStruct.PLL.PLLM = 8;
RCC_OscInitStruct.PLL.PLLN = 200;
RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;
RCC_OscInitStruct.PLL.PLLQ = 7;
RCC_OscInitStruct.PLL.PLLR = 2;
ret = HAL_RCC_OscConfig(&RCC_OscInitStruct);
if(ret != HAL_OK)
{
while(1) { ; }
}
/* Select PLL as system clock source and configure the HCLK, PCLK1 and PCLK2
clocks dividers */
RCC_ClkInitStruct.ClockType = (RCC_CLOCKTYPE_SYSCLK | RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2);
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2;
RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;
ret = HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_3);
if(ret != HAL_OK)
{
while(1) { ; }
}
}
/**
* @brief This function is executed in case of error occurrence.
* @param None
* @retval None
*/
static void Error_Handler(void)
{
while (1)
{
/* Wait 40 ms */
HAL_Delay(40);
/* Toggle LED3 */
BSP_LED_Toggle(LED3);
}
}
#ifdef USE_FULL_ASSERT
/**
* @brief Reports the name of the source file and the source line number
* where the assert_param error has occurred.
* @param file: pointer to the source file name
* @param line: assert_param error line source number
* @retval None
*/
void assert_failed(uint8_t *file, uint32_t line)
{
/* User can add his own implementation to report the file name and line number,
ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
/* Infinite loop */
while (1)
{
}
}
#endif
/**
* @}
*/
/**
* @}
*/