RTC. Setting and getting time works on STM32F4x

git-svn-id: svn://svn.code.sf.net/p/chibios/svn/branches/rtc_dev@3596 35acf78f-673a-0410-8e92-d51de3d6d3f4

3 files changed, 57 insertions, 28 deletions

diff --git a/os/hal/platforms/STM32F4xx/hal_lld.h b/os/hal/platforms/STM32F4xx/hal_lld.h
index 40064787c..496c4304f 100644
--- a/os/hal/platforms/STM32F4xx/hal_lld.h
+++ b/os/hal/platforms/STM32F4xx/hal_lld.h
@@ -320,6 +320,7 @@
 

 /* RTC attributes.*/

 #define STM32_HAS_RTC           TRUE

+#define RTC_HAS_SUBSECONDS      TRUE

 

 /* SDIO attributes.*/

 #define STM32_HAS_SDIO          TRUE

diff --git a/os/hal/platforms/STM32F4xx/rtc_lld.c b/os/hal/platforms/STM32F4xx/rtc_lld.c
index da7f73890..cdf3aff81 100644
--- a/os/hal/platforms/STM32F4xx/rtc_lld.c
+++ b/os/hal/platforms/STM32F4xx/rtc_lld.c
@@ -32,6 +32,24 @@
 #if HAL_USE_RTC || defined(__DOXYGEN__)

 

 /*===========================================================================*/

+/* Notes.                                                                    */

+/*===========================================================================*/

+/*

+This structure is used to hold the values representing a calendar time.

+It contains the following members, with the meanings as shown.

+

+int tm_sec      // seconds after minute [0-61] (61 allows for 2 leap-seconds)

+int tm_min      // minutes after hour [0-59] 

+int tm_hour     // hours after midnight [0-23] 

+int tm_mday     // day of the month [1-31] 

+int tm_mon      // month of year [0-11] 

+int tm_year     // current year-1900 

+int tm_wday     // days since Sunday [0-6] 

+int tm_yday     // days since January 1st [0-365] 

+int tm_isdst    // daylight savings indicator (1 = yes, 0 = no, -1 = unknown)

+*/

+

+/*===========================================================================*/

 /* Driver exported variables.                                                */

 /*===========================================================================*/

 

@@ -65,7 +83,11 @@ RTCDriver RTCD1;
  * @notapi

  */

 void rtc_lld_init(void){

-  uint32_t preload;

+  /* Asynchronous part of preloader. Set it to maximum value. */

+  #define PREDIV_A ((uint32_t)0x7F)

+

+  /* Add async part to preload value. */

+  uint32_t preload = PREDIV_A << 16;

 

   /* Enables access to BKP registers.*/

   PWR->CR |= PWR_CR_DBP;

@@ -77,35 +99,35 @@ void rtc_lld_init(void){
   }

 

 #if STM32_RTC == STM32_RTC_LSE

+  #define RTC_CLK   STM32_LSECLK

   if (!(RCC->BDCR & RCC_BDCR_LSEON)) {

     RCC->BDCR |= RCC_BDCR_LSEON;

     while (!(RCC->BDCR & RCC_BDCR_LSERDY))

       ;

   }

-  preload = STM32_LSECLK - 1;

+

 #elif STM32_RTC == STM32_RTC_LSI

+  #define RTC_CLK   STM32_LSICLK

   /* TODO: Move the LSI clock initialization in the HAL low level driver.*/

   RCC->CSR |= RCC_CSR_LSION;

   while (!(RCC->CSR & RCC_CSR_LSIRDY))

     ;

-  /* According to errata sheet we must wait additional 100 uS for

-     stabilization.

-     TODO: Change this code, software loops are not reliable.*/

-  uint32_t tmo = (STM32_SYSCLK / 1000000) * 100;

-  while (tmo--)

-    ;

-  preload = STM32_LSICLK - 1;

+

 #elif STM32_RTC == STM32_RTC_HSE

-  preload = (STM32_HSICLK / 128) - 1;

+  #define RTC_CLK   (STM32_HSICLK / 31)

 #endif

 

+  /* Add sync part to preload value. */

+  preload |= ((RTC_CLK / (PREDIV_A + 1)) - 1) & 0x7FFF;

+

   /* Selects clock source (previously enabled and stabilized).*/

   RCC->BDCR = (RCC->BDCR & ~RCC_BDCR_RTCSEL) | STM32_RTC;

 

   /* RTC enabled regardless its previous status.*/

   RCC->BDCR |= RCC_BDCR_RTCEN;

 

-  if (!(RTC->ISR & RTC_ISR_INITS)){/* Calendar not init yet. */

+  /* If calendar not init yet. */

+  if (!(RTC->ISR & RTC_ISR_INITS)){

     /* Disable write protection on RTC registers. */

     RTC->WPR = 0xCA;

     RTC->WPR = 0x53;

@@ -115,13 +137,9 @@ void rtc_lld_init(void){
     while(!(RTC->ISR & RTC_ISR_INITF))

       ;

     /* Prescaler registers must be written in by two separate writes. */

-    RTC->PRER = 0x007F00FF;

-    RTC->PRER = 0x007F00FF;

+    RTC->PRER = preload;

+    RTC->PRER = preload;

     RTC->ISR &= ~RTC_ISR_INIT;

-

-    /* Wait until calendar data will updated. */

-    while(!(RTC->ISR & RTC_ISR_RSF))

-      ;

   }

 

   /* Callback initially disabled.*/

@@ -147,10 +165,6 @@ void rtc_lld_set_time(RTCDriver *rtcp, const RTCTime *timespec) {
   RTC->TR = timespec->tv_time;

   RTC->DR = timespec->tv_date;

   RTC->ISR &= ~RTC_ISR_INIT;

-

-  /* Wait until calendar data will updated. */

-  while(!(RTC->ISR & RTC_ISR_RSF))

-    ;

 }

 

 /**

@@ -168,13 +182,19 @@ void rtc_lld_get_time(RTCDriver *rtcp, RTCTime *timespec) {
    * the frequency of RTCCLK, BYPSHAD must be set to ‘1’ .*/

 

   /* Wait until calendar data will updated. */

-    while(!(RTC->ISR & RTC_ISR_RSF))

-      ;

+  while(!(RTC->ISR & RTC_ISR_RSF))

+    ;

 

   timespec->tv_time = RTC->TR;

   timespec->tv_date = RTC->DR;

+#if RTC_HAS_SUBSECONDS

+  timespec->tv_msec = ((RTC->PRER & 0x7FFF) - RTC->SSR) / ((RTC->PRER & 0x7FFF) + 1);

+#else

+  timespec->tv_msec = 0;

+#endif /* STM32_RTC_HAS_SUBSECONDS */

 }

 

+

 /**

  * @brief   Set alarm time.

  *

@@ -189,7 +209,6 @@ void rtc_lld_get_time(RTCDriver *rtcp, RTCTime *timespec) {
 void rtc_lld_set_alarm(RTCDriver *rtcp,

                        rtcalarm_t alarm,

                        const RTCAlarm *alarmspec) {

-

   (void)rtcp;

   (void)alarm;

   (void)alarmspec;

diff --git a/os/hal/platforms/STM32F4xx/rtc_lld.h b/os/hal/platforms/STM32F4xx/rtc_lld.h
index 529215483..dd5a4160e 100644
--- a/os/hal/platforms/STM32F4xx/rtc_lld.h
+++ b/os/hal/platforms/STM32F4xx/rtc_lld.h
@@ -41,7 +41,7 @@
 #define RTC_SUPPORTS_CALLBACKS      TRUE

 

 /**

- * @brief   One alarm comparator available.

+ * @brief   Two alarm comparators available on STM32F4x.

  */

 #define RTC_ALARMS                  2

 

@@ -62,6 +62,10 @@
 #error "invalid source selected for RTC clock"

 #endif

 

+#if RTC_SUPPORTS_CALLBACKS && !(HAL_USE_EXT)

+#error "interrupts from STM32 RTC works only through EXTI"

+#endif

+

 /*===========================================================================*/

 /* Driver data structures and types.                                         */

 /*===========================================================================*/

@@ -97,13 +101,18 @@ typedef void (*rtccb_t)(RTCDriver *rtcp, rtcevent_t event);
  */

 struct RTCTime {

   /**

-   * @brief RTC date register in BCD format.

+   * @brief RTC date register in STM32 BCD format.

    */

   uint32_t tv_date;

   /**

-   * @brief RTC time register in BCD format.

+   * @brief RTC time register in STM32 BCD format.

    */

   uint32_t tv_time;

+  /**

+   * @brief Fractional part of time.

+   * @note  If platform does not support subseconds than always zero.

+   */

+  uint16_t tv_msec;

 };

 

 

@@ -112,7 +121,7 @@ struct RTCTime {
  */

 struct RTCAlarm {

   /**

-   * @brief Date and time of alarm in BCD.

+   * @brief Date and time of alarm in STM32 BCD.

    */

   uint32_t tv_datetime;

 };