/**************************************************************************** * arch/arm/src/stm32/stm32_rcc.c * * Copyright (C) 2009, 2011-2012 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * 3. Neither the name NuttX nor the names of its contributors may be * used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include #include #include "up_internal.h" #include "up_arch.h" #include "chip.h" #include "stm32_rcc.h" #include "stm32_rtc.h" #include "stm32_flash.h" #include "stm32.h" #include "stm32_waste.h" /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ /* Allow up to 100 milliseconds for the high speed clock to become ready. * that is a very long delay, but if the clock does not become ready we are * hosed anyway. */ #define HSERDY_TIMEOUT (100 * CONFIG_BOARD_LOOPSPERMSEC) /**************************************************************************** * Private Functions ****************************************************************************/ /* Include chip-specific clocking initialization logic */ #if defined(CONFIG_STM32_STM32L15XX) # include "stm32l15xxx_rcc.c" #elif defined(CONFIG_STM32_STM32F10XX) # include "stm32f10xxx_rcc.c" #elif defined(CONFIG_STM32_STM32F20XX) # include "stm32f20xxx_rcc.c" #elif defined(CONFIG_STM32_STM32F30XX) # include "stm32f30xxx_rcc.c" #elif defined(CONFIG_STM32_STM32F37XX) # include "stm32f37xxx_rcc.c" #elif defined(CONFIG_STM32_STM32F40XX) # include "stm32f40xxx_rcc.c" #else # error "Unsupported STM32 chip" #endif #if defined(CONFIG_STM32_STM32L15XX) # define STM32_RCC_XXX STM32_RCC_CSR # define RCC_XXX_YYYRST RCC_CSR_RTCRST #else # define STM32_RCC_XXX STM32_RCC_BDCR # define RCC_XXX_YYYRST RCC_BDCR_BDRST #endif /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: rcc_resetbkp * * Description: * The RTC needs to reset the Backup Domain to change RTCSEL and resetting * the Backup Domain renders to disabling the LSE as consequence. In order * to avoid resetting the Backup Domain when we already configured LSE we * will reset the Backup Domain early (here). * * Input Parameters: * None * * Returned Value: * None * ****************************************************************************/ #if defined(CONFIG_RTC) && defined(CONFIG_STM32_PWR) && !defined(CONFIG_STM32_STM32F10XX) static inline void rcc_resetbkp(void) { uint32_t regval; /* Check if the RTC is already configured */ regval = getreg32(RTC_MAGIC_REG); if (regval != RTC_MAGIC) { (void)stm32_pwr_enablebkp(true); /* We might be changing RTCSEL - to ensure such changes work, we must * reset the backup domain (having backed up the RTC_MAGIC token) */ modifyreg32(STM32_RCC_XXX, 0, RCC_XXX_YYYRST); modifyreg32(STM32_RCC_XXX, RCC_XXX_YYYRST, 0); (void)stm32_pwr_enablebkp(false); } } #else # define rcc_resetbkp() #endif /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: stm32_clockconfig * * Description: * Called to establish the clock settings based on the values in board.h. * This function (by default) will reset most everything, enable the PLL, * and enable peripheral clocking for all peripherals enabled in the NuttX * configuration file. * * If CONFIG_ARCH_BOARD_STM32_CUSTOM_CLOCKCONFIG is defined, then clocking * will be enabled by an externally provided, board-specific function called * stm32_board_clockconfig(). * * Input Parameters: * None * * Returned Value: * None * ****************************************************************************/ void stm32_clockconfig(void) { /* Make sure that we are starting in the reset state */ rcc_reset(); /* Reset backup domain if appropriate */ rcc_resetbkp(); #if defined(CONFIG_ARCH_BOARD_STM32_CUSTOM_CLOCKCONFIG) /* Invoke Board Custom Clock Configuration */ stm32_board_clockconfig(); #else /* Invoke standard, fixed clock configuration based on definitions in board.h */ stm32_stdclockconfig(); #endif /* Enable peripheral clocking */ rcc_enableperipherals(); } /************************************************************************************ * Name: stm32_clockenable * * Description: * Re-enable the clock and restore the clock settings based on settings in board.h. * This function is only available to support low-power modes of operation: When * re-awakening from deep-sleep modes, it is necessary to re-enable/re-start the * PLL * * This functional performs a subset of the operations performed by * stm32_clockconfig(): It does not reset any devices, and it does not reset the * currenlty enabled peripheral clocks. * * If CONFIG_ARCH_BOARD_STM32_CUSTOM_CLOCKCONFIG is defined, then clocking will * be enabled by an externally provided, board-specific function called * stm32_board_clockconfig(). * * Input Parameters: * None * * Returned Value: * None * ************************************************************************************/ #ifdef CONFIG_PM void stm32_clockenable(void) { #if defined(CONFIG_ARCH_BOARD_STM32_CUSTOM_CLOCKCONFIG) /* Invoke Board Custom Clock Configuration */ stm32_board_clockconfig(); #else /* Invoke standard, fixed clock configuration based on definitions in board.h */ stm32_stdclockconfig(); #endif } #endif