/** * * WARNING! This file has been highly modified by // ML during ParaTNC porting * from STM32F100 to STM32L4xx family * ****************************************************************************** * @file system_stm32l4xx.c * @author MCD Application Team * @brief CMSIS Cortex-M4 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_stm32l4xx.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. * * After each device reset the MSI (4 MHz) is used as system clock source. * Then SystemInit() function is called, in "startup_stm32l4xx.s" file, to * configure the system clock before to branch to main program. * * This file configures the system clock as follows: *============================================================================= *----------------------------------------------------------------------------- * System Clock source | MSI *----------------------------------------------------------------------------- * SYSCLK(Hz) | 4000000 *----------------------------------------------------------------------------- * HCLK(Hz) | 4000000 *----------------------------------------------------------------------------- * AHB Prescaler | 1 *----------------------------------------------------------------------------- * APB1 Prescaler | 1 *----------------------------------------------------------------------------- * APB2 Prescaler | 1 *----------------------------------------------------------------------------- * PLL_M | 1 *----------------------------------------------------------------------------- * PLL_N | 8 *----------------------------------------------------------------------------- * PLL_P | 7 *----------------------------------------------------------------------------- * PLL_Q | 2 *----------------------------------------------------------------------------- * PLL_R | 2 *----------------------------------------------------------------------------- * PLLSAI1_P | NA *----------------------------------------------------------------------------- * PLLSAI1_Q | NA *----------------------------------------------------------------------------- * PLLSAI1_R | NA *----------------------------------------------------------------------------- * PLLSAI2_P | NA *----------------------------------------------------------------------------- * PLLSAI2_Q | NA *----------------------------------------------------------------------------- * PLLSAI2_R | NA *----------------------------------------------------------------------------- * Require 48MHz for USB OTG FS, | Disabled * SDIO and RNG clock | *----------------------------------------------------------------------------- *============================================================================= ****************************************************************************** * @attention * *

© Copyright (c) 2017 STMicroelectronics. * All rights reserved.

* * This software component is licensed by ST under Apache License, Version 2.0, * 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/Apache-2.0 * ****************************************************************************** */ /** @addtogroup CMSIS * @{ */ /** @addtogroup stm32l4xx_system * @{ */ /** @addtogroup STM32L4xx_System_Private_Includes * @{ */ #include "stm32l4xx.h" #include "stm32l4xx_ll_rcc.h" #include "stm32l4xx_hal_rcc.h" #include "stm32l4xx_hal_flash.h" #include "stm32l4xx_hal_pwr_ex.h" /** * @} */ /** @addtogroup STM32L4xx_System_Private_TypesDefinitions * @{ */ /** * @} */ /** @addtogroup STM32L4xx_System_Private_Defines * @{ */ #define SYSTEM_CLOCK_RTC_CLOCK_TIMEOUT 0xFFFF #if !defined (HSE_VALUE) #define HSE_VALUE 8000000U /*!< Value of the External oscillator in Hz */ #endif /* HSE_VALUE */ #if !defined (MSI_VALUE) #define MSI_VALUE 4000000U /*!< Value of the Internal oscillator in Hz*/ #endif /* MSI_VALUE */ #if !defined (HSI_VALUE) #define HSI_VALUE 16000000U /*!< Value of the Internal oscillator in Hz*/ #endif /* HSI_VALUE */ /* Note: Following vector table addresses must be defined in line with linker configuration. */ /*!< Uncomment the following line if you need to relocate the vector table anywhere in Flash or Sram, else the vector table is kept at the automatic remap of boot address selected */ /* #define USER_VECT_TAB_ADDRESS */ #if defined(USER_VECT_TAB_ADDRESS) /*!< Uncomment the following line if you need to relocate your vector Table in Sram else user remap will be done in Flash. */ /* #define VECT_TAB_SRAM */ #if defined(VECT_TAB_SRAM) #define VECT_TAB_BASE_ADDRESS SRAM1_BASE /*!< Vector Table base address field. This value must be a multiple of 0x200. */ #define VECT_TAB_OFFSET 0x00000000U /*!< Vector Table base offset field. This value must be a multiple of 0x200. */ #else #define VECT_TAB_BASE_ADDRESS FLASH_BASE /*!< Vector Table base address field. This value must be a multiple of 0x200. */ #define VECT_TAB_OFFSET 0x00000000U /*!< Vector Table base offset field. This value must be a multiple of 0x200. */ #endif /* VECT_TAB_SRAM */ #endif /* USER_VECT_TAB_ADDRESS */ /******************************************************************************/ /** * @} */ /** @addtogroup STM32L4xx_System_Private_Macros * @{ */ /** * @} */ /** @addtogroup STM32L4xx_System_Private_Variables * @{ */ /* The SystemCoreClock 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 = 4000000U; const uint8_t AHBPrescTable[16] = {0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 1U, 2U, 3U, 4U, 6U, 7U, 8U, 9U}; const uint8_t APBPrescTable[8] = {0U, 0U, 0U, 0U, 1U, 2U, 3U, 4U}; const uint32_t MSIRangeTable[12] = {100000U, 200000U, 400000U, 800000U, 1000000U, 2000000U, \ 4000000U, 8000000U, 16000000U, 24000000U, 32000000U, 48000000U}; /** * @} */ /** @addtogroup STM32L4xx_System_Private_FunctionPrototypes * @{ */ /** * @} */ /** @addtogroup STM32L4xx_System_Private_Functions * @{ */ /** * @brief Setup the microcontroller system. * @retval None */ void SystemInit(void) { #if defined(USER_VECT_TAB_ADDRESS) /* Configure the Vector Table location -------------------------------------*/ SCB->VTOR = VECT_TAB_BASE_ADDRESS | VECT_TAB_OFFSET; #endif /* FPU settings ------------------------------------------------------------*/ #if (__FPU_PRESENT == 1) && (__FPU_USED == 1) SCB->CPACR |= ((3UL << 20U)|(3UL << 22U)); /* set CP10 and CP11 Full Access */ #endif /* Reset the RCC clock configuration to the default reset state ------------*/ /* Set MSION bit */ RCC->CR |= RCC_CR_MSION; /* Reset CFGR register */ RCC->CFGR = 0x00000000U; /* Reset HSEON, CSSON , HSION, and PLLON bits */ RCC->CR &= 0xEAF6FFFFU; /* Reset PLLCFGR register */ RCC->PLLCFGR = 0x00001000U; /* Reset HSEBYP bit */ RCC->CR &= 0xFFFBFFFFU; /* Disable all interrupts */ RCC->CIER = 0x00000000U; } /** * @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 MSI, SystemCoreClock will contain the MSI_VALUE(*) * * - 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(*) or MSI_VALUE(*) multiplied/divided by the PLL factors. * * (*) MSI_VALUE is a constant defined in stm32l4xx_hal.h file (default value * 4 MHz) but the real value may vary depending on the variations * in voltage and temperature. * * (**) HSI_VALUE is a constant defined in stm32l4xx_hal.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 stm32l4xx_hal.h file (default value * 8 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. * * @retval None */ void system_clock_update_l4(void) { uint32_t tmp, msirange, pllvco, pllsource, pllm, pllr; /* Get MSI Range frequency--------------------------------------------------*/ if ((RCC->CR & RCC_CR_MSIRGSEL) == 0U) { /* MSISRANGE from RCC_CSR applies */ msirange = (RCC->CSR & RCC_CSR_MSISRANGE) >> 8U; } else { /* MSIRANGE from RCC_CR applies */ msirange = (RCC->CR & RCC_CR_MSIRANGE) >> 4U; } /*MSI frequency range in HZ*/ msirange = MSIRangeTable[msirange]; /* Get SYSCLK source -------------------------------------------------------*/ switch (RCC->CFGR & RCC_CFGR_SWS) { case 0x00: /* MSI used as system clock source */ SystemCoreClock = msirange; break; case 0x04: /* HSI used as system clock source */ SystemCoreClock = HSI_VALUE; break; case 0x08: /* HSE used as system clock source */ SystemCoreClock = HSE_VALUE; break; case 0x0C: /* PLL used as system clock source */ /* PLL_VCO = (HSE_VALUE or HSI_VALUE or MSI_VALUE/ PLLM) * PLLN SYSCLK = PLL_VCO / PLLR */ pllsource = (RCC->PLLCFGR & RCC_PLLCFGR_PLLSRC); pllm = ((RCC->PLLCFGR & RCC_PLLCFGR_PLLM) >> 4U) + 1U ; switch (pllsource) { case 0x02: /* HSI used as PLL clock source */ pllvco = (HSI_VALUE / pllm); break; case 0x03: /* HSE used as PLL clock source */ pllvco = (HSE_VALUE / pllm); break; default: /* MSI used as PLL clock source */ pllvco = (msirange / pllm); break; } pllvco = pllvco * ((RCC->PLLCFGR & RCC_PLLCFGR_PLLN) >> 8U); pllr = (((RCC->PLLCFGR & RCC_PLLCFGR_PLLR) >> 25U) + 1U) * 2U; SystemCoreClock = pllvco/pllr; break; default: SystemCoreClock = msirange; break; } /* Compute HCLK clock frequency --------------------------------------------*/ /* Get HCLK prescaler */ tmp = AHBPrescTable[((RCC->CFGR & RCC_CFGR_HPRE) >> 4U)]; /* HCLK clock frequency */ SystemCoreClock >>= tmp; } /** * @brief System Clock Configuration * @retval None */ int system_clock_configure_l4(void) { /** Configure LSE Drive Capability */ //HAL_PWR_EnableBkUpAccess(); //__HAL_RCC_LSEDRIVE_CONFIG(RCC_LSEDRIVE_LOW); // set the flash latency FLASH->ACR |= FLASH_ACR_LATENCY_2WS; /** Initializes the RCC Oscillators according to the specified parameters * in the RCC_OscInitTypeDef structure. */ // select MSI as system clock cource // RCC_CFGR_SW_MSI RCC->CFGR &= (0xFFFFFFFF ^ RCC_CFGR_SW_Msk); // turn on high speed external quartz oscilator RCC->CR |= RCC_CR_HSEON; // turn of the PLL1 before any configuration change RCC->CR &= (0xFFFFFFFF ^ RCC_CR_PLLON); // be sure that PLL is not running while ((RCC->CR & RCC_CR_PLLRDY) != 0); // reset PLLCFGR register RCC->PLLCFGR = 0; // set the clock source for PLL RCC->PLLCFGR |= RCC_PLLCFGR_PLLSRC_HSE; // R division factor for PLL to /4 (DIV4) RCC->PLLCFGR |= RCC_PLLCFGR_PLLR_0; // Q divistion factor for PLL to /2 (DIV2) RCC->PLLCFGR &= (0xFFFFFFFF ^ (RCC_PLLCFGR_PLLQ_Msk)); // P division factor for PLL to /7 (DIV7) RCC->PLLCFGR &= (0xFFFFFFFF ^ (RCC_PLLCFGR_PLLP_Msk)); // M multiplication factor to 1 RCC->PLLCFGR &= (0xFFFFFFFF ^ (RCC_PLLCFGR_PLLM_Msk)); // N multiplication factor to 12 RCC->PLLCFGR |= (12 << RCC_PLLCFGR_PLLN_Pos); // turn on the PLL RCC->CR |= RCC_CR_PLLON; // wait for PLL to startup and lock while ((RCC->CR & RCC_CR_PLLRDY) == 0); // turn on all PLL outputs RCC->PLLCFGR |= RCC_PLLCFGR_PLLREN; RCC->PLLCFGR |= RCC_PLLCFGR_PLLPEN; RCC->PLLCFGR |= RCC_PLLCFGR_PLLQEN; // turn on LSI (required by IWDG) RCC->CSR |= RCC_CSR_LSION; // select PLL as a system clock RCC->CFGR |= RCC_CFGR_SW_PLL; // wait for the clock to switch while ((RCC->CFGR & RCC_CFGR_SWS_PLL) != RCC_CFGR_SWS_PLL); // configure clock sources for some peripherals RCC->CCIPR |= (RCC_CCIPR_ADCSEL | RCC_CCIPR_CLK48SEL_1); // system clock selected for ADC return 0; } int system_clock_configure_rtc_l4(void) { int retval = 0; volatile uint32_t timeout_counter = 0; // check if LSE is working now uint8_t lse_is_working = ((RCC->BDCR & RCC_BDCR_LSERDY) > 0) ? 1 : 0; // if LSE is not working reinitialize everything if (lse_is_working == 0) { // reset backup domain RCC->BDCR |= RCC_BDCR_BDRST; // wait for the reset while (timeout_counter < SYSTEM_CLOCK_RTC_CLOCK_TIMEOUT) { // wait a little bit for a reset to be done timeout_counter++; } // but clear reset flag before RCC->BDCR &= (0xFFFFFFFF ^ RCC_BDCR_BDRST); // enable access to backup domain PWR->CR1 |= PWR_CR1_DBP; // set the clock source for RTC clock to LSE RCC->BDCR |= RCC_BDCR_RTCSEL_0; // set LSE quartz driving to medium-high RCC->BDCR |= RCC_BDCR_LSEDRV_1; // turn on LSE RCC->BDCR |= RCC_BDCR_LSEON; // wait for LSE to start while((RCC->BDCR & RCC_BDCR_LSERDY) == 0); // starting RTC RCC->BDCR |= RCC_BDCR_RTCEN; // enable write access to RTC registers by writing two magic words RTC->WPR = 0xCA; RTC->WPR = 0x53; // enter the clock set mode RTC->ISR |= RTC_ISR_INIT; // wait for going into clock set mode while((RTC->ISR & RTC_ISR_INITF) == 0); // set date RTC->DR = 0x0021A820; // set time RTC->TR = 0x00232711; // exit RTC set mode RTC->ISR &= (0xFFFFFFFF ^ RTC_ISR_INIT); // set the source clock for RTC wakeup as CK_SPRE RTC->CR |= RTC_CR_WUCKSEL_2; } return retval; } void system_clock_configure_auto_wakeup_l4(uint16_t seconds) { // enable access to backup domain PWR->CR1 |= PWR_CR1_DBP; // enable write access to RTC registers by writing two magic words RTC->WPR = 0xCA; RTC->WPR = 0x53; // disable wakeup timer RTC->CR &= (0xFFFFFFFF ^ RTC_CR_WUTE); // wait for wakeup timer to disable while((RTC->ISR & RTC_ISR_WUTWF) == 0); // clear wakeup flag RTC->ISR &= (0xFFFFFFFF ^ RTC_ISR_WUTF_Msk); // set auto wakeup timer RTC->WUTR = seconds; // start wakeup timer once again RTC->CR |= RTC_CR_WUTE; // enabling wakeup interrupt RTC->CR |= RTC_CR_WUTIE; // enable 20th EXTI Line (RTC wakeup timer) EXTI->IMR1 |= EXTI_IMR1_IM20; // set 20th EXTI line to rising trigger EXTI->RTSR1 |= EXTI_RTSR1_RT20; // by enabling this all pending interrupt will wake up cpu from low-power mode, even from those disabled in NVIC SCB->SCR |= SCB_SCR_SEVONPEND_Msk; // enable wakeup interrupt NVIC_EnableIRQ(RTC_WKUP_IRQn); } /** * @} */ /** * @} */ /** * @} */ /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/