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Diffstat (limited to 'lib/stm32f2/system_stm32f2xx.c')
| -rw-r--r-- | lib/stm32f2/system_stm32f2xx.c | 346 |
1 files changed, 346 insertions, 0 deletions
diff --git a/lib/stm32f2/system_stm32f2xx.c b/lib/stm32f2/system_stm32f2xx.c new file mode 100644 index 00000000..3c2a20b0 --- /dev/null +++ b/lib/stm32f2/system_stm32f2xx.c @@ -0,0 +1,346 @@ +/** + ****************************************************************************** + * @file system_stm32f2xx.c + * @author MCD Application Team + * @brief CMSIS Cortex-M3 Device Peripheral Access Layer System Source File. + * + * This file provides two functions and one global variable to be called from + * user application: + * - SystemInit(): This function is called at startup just after reset and + * before branch to main program. This call is made inside + * the "startup_stm32f2xx.s" file. + * + * - SystemCoreClock variable: Contains the core clock (HCLK), it can be used + * by the user application to setup the SysTick + * timer or configure other parameters. + * + * - SystemCoreClockUpdate(): Updates the variable SystemCoreClock and must + * be called whenever the core clock is changed + * during program execution. + * + ****************************************************************************** + * @attention + * + * <h2><center>© Copyright (c) 2016 STMicroelectronics. + * All rights reserved.</center></h2> + * + * This software component is licensed by ST under BSD 3-Clause license, + * the "License"; You may not use this file except in compliance with the + * License. You may obtain a copy of the License at: + * opensource.org/licenses/BSD-3-Clause + * + ****************************************************************************** + */ + +/** @addtogroup CMSIS + * @{ + */ + +/** @addtogroup stm32f2xx_system + * @{ + */ + +/** @addtogroup STM32F2xx_System_Private_Includes + * @{ + */ + +#include "stm32f2xx.h" + +#if !defined (HSE_VALUE) + #define HSE_VALUE ((uint32_t)25000000) /*!< Default value of the External oscillator in Hz */ +#endif /* HSE_VALUE */ + +#if !defined (HSI_VALUE) + #define HSI_VALUE ((uint32_t)16000000) /*!< Value of the Internal oscillator in Hz*/ +#endif /* HSI_VALUE */ + +/** + * @} + */ + +/** @addtogroup STM32F2xx_System_Private_TypesDefinitions + * @{ + */ + +/** + * @} + */ + +/** @addtogroup STM32F2xx_System_Private_Defines + * @{ + */ +/************************* Miscellaneous Configuration ************************/ +/*!< Uncomment the following line if you need to use external SRAM mounted + on STM322xG_EVAL board as data memory */ +/* #define DATA_IN_ExtSRAM */ + +/*!< Uncomment the following line if you need to relocate your vector Table in + Internal SRAM. */ +/* #define VECT_TAB_SRAM */ +#define VECT_TAB_OFFSET 0x00 /*!< Vector Table base offset field. + This value must be a multiple of 0x200. */ +/******************************************************************************/ + +/** + * @} + */ + +/** @addtogroup STM32F2xx_System_Private_Macros + * @{ + */ + +/** + * @} + */ + +/** @addtogroup STM32F2xx_System_Private_Variables + * @{ + */ + + /* This variable can be updated in Three ways : + 1) by calling CMSIS function SystemCoreClockUpdate() + 2) by calling HAL API function HAL_RCC_GetHCLKFreq() + 3) each time HAL_RCC_ClockConfig() is called to configure the system clock frequency + Note: If you use this function to configure the system clock; then there + is no need to call the 2 first functions listed above, since SystemCoreClock + variable is updated automatically. + */ + uint32_t SystemCoreClock = 16000000; + const uint8_t AHBPrescTable[16] = {0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 6, 7, 8, 9}; + const uint8_t APBPrescTable[8] = {0, 0, 0, 0, 1, 2, 3, 4}; +/** + * @} + */ + +/** @addtogroup STM32F2xx_System_Private_FunctionPrototypes + * @{ + */ + +#ifdef DATA_IN_ExtSRAM + static void SystemInit_ExtMemCtl(void); +#endif /* DATA_IN_ExtSRAM */ + +/** + * @} + */ + +/** @addtogroup STM32F2xx_System_Private_Functions + * @{ + */ + +/** + * @brief Setup the microcontroller system + * Initialize the Embedded Flash Interface, the PLL and update the + * SystemFrequency variable. + * @param None + * @retval None + */ +void SystemInit(void) +{ + /* Reset the RCC clock configuration to the default reset state ------------*/ + /* Set HSION bit */ + RCC->CR |= (uint32_t)0x00000001; + + /* Reset CFGR register */ + RCC->CFGR = 0x00000000; + + /* Reset HSEON, CSSON and PLLON bits */ + RCC->CR &= (uint32_t)0xFEF6FFFF; + + /* Reset PLLCFGR register */ + RCC->PLLCFGR = 0x24003010; + + /* Reset HSEBYP bit */ + RCC->CR &= (uint32_t)0xFFFBFFFF; + + /* Disable all interrupts */ + RCC->CIR = 0x00000000; + +#ifdef DATA_IN_ExtSRAM + SystemInit_ExtMemCtl(); +#endif /* DATA_IN_ExtSRAM */ + + /* Configure the Vector Table location add offset address ------------------*/ +#ifdef VECT_TAB_SRAM + SCB->VTOR = SRAM_BASE | VECT_TAB_OFFSET; /* Vector Table Relocation in Internal SRAM */ +#else + SCB->VTOR = FLASH_BASE | VECT_TAB_OFFSET; /* Vector Table Relocation in Internal FLASH */ +#endif +} + +/** + * @brief Update SystemCoreClock variable according to Clock Register Values. + * The SystemCoreClock variable contains the core clock (HCLK), it can + * be used by the user application to setup the SysTick timer or configure + * other parameters. + * + * @note Each time the core clock (HCLK) changes, this function must be called + * to update SystemCoreClock variable value. Otherwise, any configuration + * based on this variable will be incorrect. + * + * @note - The system frequency computed by this function is not the real + * frequency in the chip. It is calculated based on the predefined + * constant and the selected clock source: + * + * - If SYSCLK source is HSI, SystemCoreClock will contain the HSI_VALUE(*) + * + * - If SYSCLK source is HSE, SystemCoreClock will contain the HSE_VALUE(**) + * + * - If SYSCLK source is PLL, SystemCoreClock will contain the HSE_VALUE(**) + * or HSI_VALUE(*) multiplied/divided by the PLL factors. + * + * (*) HSI_VALUE is a constant defined in stm32f2xx_hal_conf.h file (default value + * 16 MHz) but the real value may vary depending on the variations + * in voltage and temperature. + * + * (**) HSE_VALUE is a constant defined in stm32f2xx_hal_conf.h file (its value + * depends on the application requirements), user has to ensure that HSE_VALUE + * is same as the real frequency of the crystal used. Otherwise, this function + * may have wrong result. + * + * - The result of this function could be not correct when using fractional + * value for HSE crystal. + * + * @param None + * @retval None + */ +void SystemCoreClockUpdate(void) +{ + uint32_t tmp = 0, pllvco = 0, pllp = 2, pllsource = 0, pllm = 2; + + /* Get SYSCLK source -------------------------------------------------------*/ + tmp = RCC->CFGR & RCC_CFGR_SWS; + + switch (tmp) + { + case 0x00: /* HSI used as system clock source */ + SystemCoreClock = HSI_VALUE; + break; + case 0x04: /* HSE used as system clock source */ + SystemCoreClock = HSE_VALUE; + break; + case 0x08: /* PLL used as system clock source */ + + /* PLL_VCO = (HSE_VALUE or HSI_VALUE / PLL_M) * PLL_N + SYSCLK = PLL_VCO / PLL_P + */ + pllsource = (RCC->PLLCFGR & RCC_PLLCFGR_PLLSRC) >> 22; + pllm = RCC->PLLCFGR & RCC_PLLCFGR_PLLM; + + if (pllsource != 0) + { + /* HSE used as PLL clock source */ + pllvco = (HSE_VALUE / pllm) * ((RCC->PLLCFGR & RCC_PLLCFGR_PLLN) >> 6); + } + else + { + /* HSI used as PLL clock source */ + pllvco = (HSI_VALUE / pllm) * ((RCC->PLLCFGR & RCC_PLLCFGR_PLLN) >> 6); + } + + pllp = (((RCC->PLLCFGR & RCC_PLLCFGR_PLLP) >>16) + 1 ) *2; + SystemCoreClock = pllvco/pllp; + break; + default: + SystemCoreClock = HSI_VALUE; + break; + } + /* Compute HCLK frequency --------------------------------------------------*/ + /* Get HCLK prescaler */ + tmp = AHBPrescTable[((RCC->CFGR & RCC_CFGR_HPRE) >> 4)]; + /* HCLK frequency */ + SystemCoreClock >>= tmp; +} + +#ifdef DATA_IN_ExtSRAM +/** + * @brief Setup the external memory controller. + * Called in startup_stm32f2xx.s before jump to main. + * This function configures the external SRAM mounted on STM322xG_EVAL board + * This SRAM will be used as program data memory (including heap and stack). + * @param None + * @retval None + */ +void SystemInit_ExtMemCtl(void) +{ + __IO uint32_t tmp = 0x00; + +/*-- GPIOs Configuration -----------------------------------------------------*/ + /* Enable GPIOD, GPIOE, GPIOF and GPIOG interface clock */ + RCC->AHB1ENR |= 0x00000078; + /* Delay after an RCC peripheral clock enabling */ + tmp = READ_BIT(RCC->AHB1ENR, RCC_AHB1ENR_GPIODEN); + (void)(tmp); + + /* Connect PDx pins to FSMC Alternate function */ + GPIOD->AFR[0] = 0x00CCC0CC; + GPIOD->AFR[1] = 0xCCCCCCCC; + /* Configure PDx pins in Alternate function mode */ + GPIOD->MODER = 0xAAAA0A8A; + /* Configure PDx pins speed to 100 MHz */ + GPIOD->OSPEEDR = 0xFFFF0FCF; + /* Configure PDx pins Output type to push-pull */ + GPIOD->OTYPER = 0x00000000; + /* No pull-up, pull-down for PDx pins */ + GPIOD->PUPDR = 0x00000000; + + /* Connect PEx pins to FSMC Alternate function */ + GPIOE->AFR[0] = 0xC00CC0CC; + GPIOE->AFR[1] = 0xCCCCCCCC; + /* Configure PEx pins in Alternate function mode */ + GPIOE->MODER = 0xAAAA828A; + /* Configure PEx pins speed to 100 MHz */ + GPIOE->OSPEEDR = 0xFFFFC3CF; + /* Configure PEx pins Output type to push-pull */ + GPIOE->OTYPER = 0x00000000; + /* No pull-up, pull-down for PEx pins */ + GPIOE->PUPDR = 0x00000000; + + /* Connect PFx pins to FSMC Alternate function */ + GPIOF->AFR[0] = 0x00CCCCCC; + GPIOF->AFR[1] = 0xCCCC0000; + /* Configure PFx pins in Alternate function mode */ + GPIOF->MODER = 0xAA000AAA; + /* Configure PFx pins speed to 100 MHz */ + GPIOF->OSPEEDR = 0xFF000FFF; + /* Configure PFx pins Output type to push-pull */ + GPIOF->OTYPER = 0x00000000; + /* No pull-up, pull-down for PFx pins */ + GPIOF->PUPDR = 0x00000000; + + /* Connect PGx pins to FSMC Alternate function */ + GPIOG->AFR[0] = 0x00CCCCCC; + GPIOG->AFR[1] = 0x000000C0; + /* Configure PGx pins in Alternate function mode */ + GPIOG->MODER = 0x00085AAA; + /* Configure PGx pins speed to 100 MHz */ + GPIOG->OSPEEDR = 0x000CAFFF; + /* Configure PGx pins Output type to push-pull */ + GPIOG->OTYPER = 0x00000000; + /* No pull-up, pull-down for PGx pins */ + GPIOG->PUPDR = 0x00000000; + +/*--FSMC Configuration -------------------------------------------------------*/ + /* Enable the FSMC interface clock */ + RCC->AHB3ENR |= 0x00000001; + + /* Configure and enable Bank1_SRAM2 */ + FSMC_Bank1->BTCR[2] = 0x00001011; + FSMC_Bank1->BTCR[3] = 0x00000201; + FSMC_Bank1E->BWTR[2] = 0x0FFFFFFF; +} +#endif /* DATA_IN_ExtSRAM */ + + +/** + * @} + */ + +/** + * @} + */ + +/** + * @} + */ +/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/ |