RTC. Added function to ensure data synchronization.

git-svn-id: svn://svn.code.sf.net/p/chibios/svn/trunk@3795 35acf78f-673a-0410-8e92-d51de3d6d3f4

1 files changed, 18 insertions, 7 deletions

diff --git a/os/hal/platforms/STM32/RTCv1/rtc_lld.c b/os/hal/platforms/STM32/RTCv1/rtc_lld.c
index b2474c71b..478b16f39 100644
--- a/os/hal/platforms/STM32/RTCv1/rtc_lld.c
+++ b/os/hal/platforms/STM32/RTCv1/rtc_lld.c
@@ -82,7 +82,20 @@ static void rtc_lld_serve_interrupt(RTCDriver *rtcp) {
 }

 

 /**

- * @brief   Acquire atomic write access to RTC registers.

+ * @brief   Wait for synchronization of RTC registers.

+ * @details Ensure that RTC_CNT and RTC_DIV contain actual values after

+ *          enabling clocking on APB1, because these values only update

+ *          when APB1 functioning.

+ *

+ * @notapi

+ */

+static void rtc_lld_wait_sync(void) {

+  while (!(RTC->CRL & RTC_CRL_RSF))

+    ;

+}

+

+/**

+ * @brief   Acquire exclusive write access to RTC registers.

  *

  * @notapi

  */

@@ -100,7 +113,7 @@ BEGIN:
 }

 

 /**

- * @brief   Release atomic write access to RTC registers.

+ * @brief   Release exclusive write access to RTC registers.

  *

  * @notapi

  */

@@ -140,12 +153,8 @@ void rtc_lld_init(void){
 

   PWR->CR |= PWR_CR_DBP;

 

-  /* Ensure that RTC_CNT and RTC_DIV contain actual values after enabling

-     clocking on APB1, because these values only update when APB1

-     functioning.*/

   RTC->CRL &= ~(RTC_CRL_OWF | RTC_CRL_ALRF | RTC_CRL_SECF);

-  while (!(RTC->CRL & RTC_CRL_RSF))

-    ;

+  rtc_lld_wait_sync();

 

   /* Write preload register only if its value is not equal to desired value.*/

   if (STM32_RTCCLK != (((uint32_t)(RTC->PRLH)) << 16) +

@@ -213,6 +222,7 @@ void rtc_lld_get_time(RTCDriver *rtcp, RTCTime *timespec) {
 

   /* The read is repeated until we are able to do it twice and obtain the

      same result.*/

+  rtc_lld_wait_sync();

   do {

     timespec->tv_sec = ((uint32_t)(RTC->CNTH) << 16) + RTC->CNTL;

     time_frac = (((uint32_t)RTC->DIVH) << 16) + (uint32_t)RTC->DIVL;

@@ -278,6 +288,7 @@ void rtc_lld_get_alarm(RTCDriver *rtcp,
   (void)rtcp;

   (void)alarm;

 

+  rtc_lld_wait_sync();

   alarmspec->tv_sec = ((RTC->ALRH << 16) + RTC->ALRL);

 }