STM32CubeF7/Projects/STM32746G-Discovery/Examples/RCC/RCC_ClockConfig/Src/system_stm32f7xx.c

421 lines
13 KiB
C

/**
******************************************************************************
* @file system_stm32f7xx.c
* @author MCD Application Team
* @brief CMSIS Cortex-M7 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_stm32f7xx.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
*
* Copyright (c) 2016 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.
*
******************************************************************************
*/
/** @addtogroup CMSIS
* @{
*/
/** @addtogroup stm32f7xx_system
* @{
*/
/** @addtogroup STM32F7xx_System_Private_Includes
* @{
*/
#include "stm32f7xx.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 STM32F7xx_System_Private_TypesDefinitions
* @{
*/
/**
* @}
*/
/** @addtogroup STM32F7xx_System_Private_Defines
* @{
*/
/************************* Miscellaneous Configuration ************************/
/*!< Uncomment the following line if you need to use external SDRAM mounted
on DK as data memory */
/* #define DATA_IN_ExtSDRAM */
/*!< 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 STM32F7xx_System_Private_Macros
* @{
*/
/**
* @}
*/
/** @addtogroup STM32F7xx_System_Private_Variables
* @{
*/
/* This variable is 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 STM32F7xx_System_Private_FunctionPrototypes
* @{
*/
#if defined (DATA_IN_ExtSDRAM)
static void SystemInit_ExtMemCtl(void);
#endif /* DATA_IN_ExtSDRAM */
/**
* @}
*/
/** @addtogroup STM32F7xx_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)
{
/* FPU settings ------------------------------------------------------------*/
#if (__FPU_PRESENT == 1) && (__FPU_USED == 1)
SCB->CPACR |= ((3UL << 10*2)|(3UL << 11*2)); /* set CP10 and CP11 Full Access */
#endif
/* 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;
#if defined (DATA_IN_ExtSDRAM)
SystemInit_ExtMemCtl();
#endif /* DATA_IN_ExtSDRAM */
/* Configure the Vector Table location add offset address ------------------*/
#ifdef VECT_TAB_SRAM
SCB->VTOR = SRAM1_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 stm32f7xx.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 stm32f7xx.h file (default value
* 25 MHz), 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;
}
#if defined (DATA_IN_ExtSDRAM)
/**
* @brief Setup the external memory controller.
* Called in startup_stm32f7xx.s before jump to main.
* This function configures the external memories (SDRAM)
* This SDRAM will be used as program data memory (including heap and stack).
* @param None
* @retval None
*/
void SystemInit_ExtMemCtl(void)
{
register uint32_t tmpreg = 0, timeout = 0xFFFF;
register __IO uint32_t index;
/* Enable GPIOC, GPIOD, GPIOE, GPIOF, GPIOG and GPIOH interface
clock */
RCC->AHB1ENR |= 0x000000FC;
/* Connect PCx pins to FMC Alternate function */
GPIOC->AFR[0] = 0x0000C000;
GPIOC->AFR[1] = 0x00000000;
/* Configure PCx pins in Alternate function mode */
GPIOC->MODER = 0x00000080;
/* Configure PCx pins speed to 50 MHz */
GPIOC->OSPEEDR = 0x00000080;
/* Configure PCx pins Output type to push-pull */
GPIOC->OTYPER = 0x00000000;
/* No pull-up, pull-down for PCx pins */
GPIOC->PUPDR = 0x00000040;
/* Connect PDx pins to FMC Alternate function */
GPIOD->AFR[0] = 0x000000CC;
GPIOD->AFR[1] = 0xCC000CCC;
/* Configure PDx pins in Alternate function mode */
GPIOD->MODER = 0xA02A000A;
/* Configure PDx pins speed to 50 MHz */
GPIOD->OSPEEDR = 0xA02A000A;
/* Configure PDx pins Output type to push-pull */
GPIOD->OTYPER = 0x00000000;
/* No pull-up, pull-down for PDx pins */
GPIOD->PUPDR = 0x50150005;
/* Connect PEx pins to FMC Alternate function */
GPIOE->AFR[0] = 0xC00000CC;
GPIOE->AFR[1] = 0xCCCCCCCC;
/* Configure PEx pins in Alternate function mode */
GPIOE->MODER = 0xAAAA800A;
/* Configure PEx pins speed to 50 MHz */
GPIOE->OSPEEDR = 0xAAAA800A;
/* Configure PEx pins Output type to push-pull */
GPIOE->OTYPER = 0x00000000;
/* No pull-up, pull-down for PEx pins */
GPIOE->PUPDR = 0x55554005;
/* Connect PFx pins to FMC Alternate function */
GPIOF->AFR[0] = 0x00CCCCCC;
GPIOF->AFR[1] = 0xCCCCC000;
/* Configure PFx pins in Alternate function mode */
GPIOF->MODER = 0xAA800AAA;
/* Configure PFx pins speed to 50 MHz */
GPIOF->OSPEEDR = 0xAA800AAA;
/* Configure PFx pins Output type to push-pull */
GPIOF->OTYPER = 0x00000000;
/* No pull-up, pull-down for PFx pins */
GPIOF->PUPDR = 0x55400555;
/* Connect PGx pins to FMC Alternate function */
GPIOG->AFR[0] = 0x00CC00CC;
GPIOG->AFR[1] = 0xC000000C;
/* Configure PGx pins in Alternate function mode */
GPIOG->MODER = 0x80020A0A;
/* Configure PGx pins speed to 50 MHz */
GPIOG->OSPEEDR = 0x80020A0A;
/* Configure PGx pins Output type to push-pull */
GPIOG->OTYPER = 0x00000000;
/* No pull-up, pull-down for PGx pins */
GPIOG->PUPDR = 0x40010505;
/* Connect PHx pins to FMC Alternate function */
GPIOH->AFR[0] = 0x00C0C000;
GPIOH->AFR[1] = 0x00000000;
/* Configure PHx pins in Alternate function mode */
GPIOH->MODER = 0x00000880;
/* Configure PHx pins speed to 50 MHz */
GPIOH->OSPEEDR = 0x00000880;
/* Configure PHx pins Output type to push-pull */
GPIOH->OTYPER = 0x00000000;
/* No pull-up, pull-down for PHx pins */
GPIOH->PUPDR = 0x00000440;
/* Enable the FMC interface clock */
RCC->AHB3ENR |= 0x00000001;
/* Configure and enable SDRAM bank1 */
FMC_Bank5_6->SDCR[0] = 0x00001954;
FMC_Bank5_6->SDTR[0] = 0x01115351;
/* SDRAM initialization sequence */
/* Clock enable command */
FMC_Bank5_6->SDCMR = 0x00000011;
tmpreg = FMC_Bank5_6->SDSR & 0x00000020;
while((tmpreg != 0) && (timeout-- > 0))
{
tmpreg = FMC_Bank5_6->SDSR & 0x00000020;
}
/* Delay */
for (index = 0; index<1000; index++);
/* PALL command */
FMC_Bank5_6->SDCMR = 0x00000012;
timeout = 0xFFFF;
while((tmpreg != 0) && (timeout-- > 0))
{
tmpreg = FMC_Bank5_6->SDSR & 0x00000020;
}
/* Auto refresh command */
FMC_Bank5_6->SDCMR = 0x000000F3;
timeout = 0xFFFF;
while((tmpreg != 0) && (timeout-- > 0))
{
tmpreg = FMC_Bank5_6->SDSR & 0x00000020;
}
/* MRD register program */
FMC_Bank5_6->SDCMR = 0x00044014;
timeout = 0xFFFF;
while((tmpreg != 0) && (timeout-- > 0))
{
tmpreg = FMC_Bank5_6->SDSR & 0x00000020;
}
/* Set refresh count */
tmpreg = FMC_Bank5_6->SDRTR;
FMC_Bank5_6->SDRTR = (tmpreg | (0x0000050C<<1));
/* Disable write protection */
tmpreg = FMC_Bank5_6->SDCR[0];
FMC_Bank5_6->SDCR[0] = (tmpreg & 0xFFFFFDFF);
/*
* Disable the FMC bank1 (enabled after reset).
* This, prevents CPU speculation access on this bank which blocks the use of FMC during
* 24us. During this time the others FMC master (such as LTDC) cannot use it!
*/
FMC_Bank1->BTCR[0] = 0x000030d2;
}
#endif /* DATA_IN_ExtSDRAM */
/**
* @}
*/
/**
* @}
*/
/**
* @}
*/