added prescaler for 16 bit pwm in LPC1347 target
Fork of mbed-dev by
Diff: targets/hal/TARGET_Silicon_Labs/TARGET_EFM32/emlib/src/em_wdog.c
- Revision:
- 0:9b334a45a8ff
- Child:
- 50:a417edff4437
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/targets/hal/TARGET_Silicon_Labs/TARGET_EFM32/emlib/src/em_wdog.c Thu Oct 01 15:25:22 2015 +0300 @@ -0,0 +1,225 @@ +/***************************************************************************//** + * @file em_wdog.c + * @brief Watchdog (WDOG) peripheral API + * devices. + * @version 3.20.12 + ******************************************************************************* + * @section License + * <b>(C) Copyright 2014 Silicon Labs, http://www.silabs.com</b> + ******************************************************************************* + * + * Permission is granted to anyone to use this software for any purpose, + * including commercial applications, and to alter it and redistribute it + * freely, subject to the following restrictions: + * + * 1. The origin of this software must not be misrepresented; you must not + * claim that you wrote the original software. + * 2. Altered source versions must be plainly marked as such, and must not be + * misrepresented as being the original software. + * 3. This notice may not be removed or altered from any source distribution. + * + * DISCLAIMER OF WARRANTY/LIMITATION OF REMEDIES: Silicon Labs has no + * obligation to support this Software. Silicon Labs is providing the + * Software "AS IS", with no express or implied warranties of any kind, + * including, but not limited to, any implied warranties of merchantability + * or fitness for any particular purpose or warranties against infringement + * of any proprietary rights of a third party. + * + * Silicon Labs will not be liable for any consequential, incidental, or + * special damages, or any other relief, or for any claim by any third party, + * arising from your use of this Software. + * + ******************************************************************************/ + + +#include "em_wdog.h" +#if defined(WDOG_COUNT) && (WDOG_COUNT > 0) + +#include "em_bitband.h" + +/***************************************************************************//** + * @addtogroup EM_Library + * @{ + ******************************************************************************/ + +/***************************************************************************//** + * @addtogroup WDOG + * @brief Watchdog (WDOG) Peripheral API + * @{ + ******************************************************************************/ + +/******************************************************************************* + ************************** GLOBAL FUNCTIONS ******************************* + ******************************************************************************/ + +/***************************************************************************//** + * @brief + * Enable/disable the watchdog timer. + * + * @note + * This function modifies the WDOG CTRL register which requires + * synchronization into the low frequency domain. If this register is modified + * before a previous update to the same register has completed, this function + * will stall until the previous synchronization has completed. + * + * @param[in] enable + * true to enable watchdog, false to disable. Watchdog cannot be disabled if + * watchdog has been locked. + ******************************************************************************/ +void WDOG_Enable(bool enable) +{ + if (!enable) + { + /* Wait for any pending previous write operation to have been completed in */ + /* low frequency domain */ + while (WDOG->SYNCBUSY & WDOG_SYNCBUSY_CTRL) + ; + } + BITBAND_Peripheral(&(WDOG->CTRL), _WDOG_CTRL_EN_SHIFT, (unsigned int)enable); +} + + +/***************************************************************************//** + * @brief + * Feed the watchdog. + * + * @details + * When the watchdog is activated, it must be fed (ie clearing the counter) + * before it reaches the defined timeout period. Otherwise, the watchdog + * will generate a reset. + ******************************************************************************/ +void WDOG_Feed(void) +{ + /* The watchdog should not be fed while it is disabled */ + if ( !(WDOG->CTRL & WDOG_CTRL_EN) ) + { + return; + } + + /* If a previous clearing is being synchronized to LF domain, then there */ + /* is no point in waiting for it to complete before clearing over again. */ + /* This avoids stalling the core in the typical use case where some idle loop */ + /* keeps clearing the watchdog. */ + if (WDOG->SYNCBUSY & WDOG_SYNCBUSY_CMD) + { + return; + } + /* Before writing to the WDOG_CMD register we also need to make sure that + * any previous write to WDOG_CTRL is complete. */ + while ( WDOG->SYNCBUSY & WDOG_SYNCBUSY_CTRL ); + + WDOG->CMD = WDOG_CMD_CLEAR; +} + + +/***************************************************************************//** + * @brief + * Initialize watchdog (assuming the watchdog configuration has not been + * locked). + * + * @note + * This function modifies the WDOG CTRL register which requires + * synchronization into the low frequency domain. If this register is modified + * before a previous update to the same register has completed, this function + * will stall until the previous synchronization has completed. + * + * @param[in] init + * Structure holding watchdog configuration. A default setting + * #WDOG_INIT_DEFAULT is available for init. + ******************************************************************************/ +void WDOG_Init(const WDOG_Init_TypeDef *init) +{ + uint32_t setting; + + if (init->enable) + { + setting = WDOG_CTRL_EN; + } + else + { + setting = 0; + } + + if (init->debugRun) + { + setting |= WDOG_CTRL_DEBUGRUN; + } + + if (init->em2Run) + { + setting |= WDOG_CTRL_EM2RUN; + } + + if (init->em3Run) + { + setting |= WDOG_CTRL_EM3RUN; + } + + if (init->em4Block) + { + setting |= WDOG_CTRL_EM4BLOCK; + } + + if (init->swoscBlock) + { + setting |= WDOG_CTRL_SWOSCBLOCK; + } + + setting |= ((uint32_t)(init->clkSel) << _WDOG_CTRL_CLKSEL_SHIFT) | + ((uint32_t)(init->perSel) << _WDOG_CTRL_PERSEL_SHIFT); + + /* Wait for any pending previous write operation to have been completed in */ + /* low frequency domain */ + while (WDOG->SYNCBUSY & WDOG_SYNCBUSY_CTRL) + ; + + WDOG->CTRL = setting; + + /* Optional register locking */ + if (init->lock) + { + if (init->enable) + { + WDOG_Lock(); + } + else + { + BITBAND_Peripheral(&(WDOG->CTRL), _WDOG_CTRL_LOCK_SHIFT, 1); + } + } +} + + +/***************************************************************************//** + * @brief + * Lock the watchdog configuration. + * + * @details + * This prevents errors from overwriting the watchdog configuration, possibly + * disabling it. Only a reset can unlock the watchdog config, once locked. + * + * If the LFRCO or LFXO clocks are used to clock the watchdog, one should + * consider using the option of inhibiting those clocks to be disabled, + * please see the WDOG_Enable() init structure. + * + * @note + * This function modifies the WDOG CTRL register which requires + * synchronization into the low frequency domain. If this register is modified + * before a previous update to the same register has completed, this function + * will stall until the previous synchronization has completed. + ******************************************************************************/ +void WDOG_Lock(void) +{ + /* Wait for any pending previous write operation to have been completed in */ + /* low frequency domain */ + while (WDOG->SYNCBUSY & WDOG_SYNCBUSY_CTRL) + ; + + /* Disable writing to the control register */ + BITBAND_Peripheral(&(WDOG->CTRL), _WDOG_CTRL_LOCK_SHIFT, 1); +} + + +/** @} (end addtogroup WDOG) */ +/** @} (end addtogroup EM_Library) */ +#endif /* defined(WDOG_COUNT) && (WDOG_COUNT > 0) */