tinySA/os/hal/ports/STM32/LLD/xWDGv1/wdg_lld.c

141 lines
4.1 KiB
C

/*
ChibiOS - Copyright (C) 2006..2015 Giovanni Di Sirio
Licensed under the 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
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
/**
* @file wdg_lld.c
* @brief WDG Driver subsystem low level driver source.
*
* @addtogroup WDG
* @{
*/
#include "hal.h"
#if HAL_USE_WDG || defined(__DOXYGEN__)
/*===========================================================================*/
/* Driver local definitions. */
/*===========================================================================*/
#define KR_KEY_RELOAD 0xAAAAU
#define KR_KEY_ENABLE 0xCCCCU
#define KR_KEY_WRITE 0x5555U
#define KR_KEY_PROTECT 0x0000U
/*===========================================================================*/
/* Driver exported variables. */
/*===========================================================================*/
#if STM32_WDG_USE_IWDG || defined(__DOXYGEN__)
WDGDriver WDGD1;
#endif
/*===========================================================================*/
/* Driver local variables. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver local functions. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver interrupt handlers. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver exported functions. */
/*===========================================================================*/
/**
* @brief Low level WDG driver initialization.
*
* @notapi
*/
void wdg_lld_init(void) {
#if STM32_WDG_USE_IWDG
WDGD1.state = WDG_STOP;
WDGD1.wdg = IWDG;
#endif
}
/**
* @brief Configures and activates the WDG peripheral.
*
* @param[in] wdgp pointer to the @p WDGDriver object
*
* @notapi
*/
void wdg_lld_start(WDGDriver *wdgp) {
#if STM32_IWDG_IS_WINDOWED
/* Enable IWDG and unlock for write.*/
wdgp->wdg->KR = KR_KEY_ENABLE;
wdgp->wdg->KR = KR_KEY_WRITE;
/* Write configuration.*/
wdgp->wdg->PR = wdgp->config->pr;
wdgp->wdg->RLR = wdgp->config->rlr;
while (wdgp->wdg->SR != 0)
;
/* This also triggers a refresh.*/
wdgp->wdg->WINR = wdgp->config->winr;
#else
/* Unlock IWDG.*/
wdgp->wdg->KR = KR_KEY_WRITE;
/* Write configuration.*/
wdgp->wdg->PR = wdgp->config->pr;
wdgp->wdg->RLR = wdgp->config->rlr;
while (wdgp->wdg->SR != 0)
;
/* Start operations.*/
wdgp->wdg->KR = KR_KEY_RELOAD;
wdgp->wdg->KR = KR_KEY_ENABLE;
#endif
}
/**
* @brief Deactivates the WDG peripheral.
*
* @param[in] wdgp pointer to the @p WDGDriver object
*
* @api
*/
void wdg_lld_stop(WDGDriver *wdgp) {
osalDbgAssert(wdgp->state == WDG_STOP,
"IWDG cannot be stopped once activated");
}
/**
* @brief Reloads WDG's counter.
*
* @param[in] idwgp pointer to the @p WDGDriver object
*
* @notapi
*/
void wdg_lld_reset(WDGDriver * wdgp) {
wdgp->wdg->KR = KR_KEY_RELOAD;
}
#endif /* HAL_USE_WDG */
/** @} */