RTC. Initial commit.

git-svn-id: svn://svn.code.sf.net/p/chibios/svn/branches/rtc_dev@3269 35acf78f-673a-0410-8e92-d51de3d6d3f4

2 files changed, 336 insertions, 0 deletions

diff --git a/os/hal/platforms/STM32/rtc_lld.c b/os/hal/platforms/STM32/rtc_lld.c
new file mode 100644
index 000000000..4af863005
--- /dev/null
+++ b/os/hal/platforms/STM32/rtc_lld.c
@@ -0,0 +1,236 @@
+/**

+ * @file    STM32/rtc_lld.c

+ * @brief   STM32 RTC subsystem low level driver header.

+ *

+ * @addtogroup RTC

+ * @{

+ */

+

+#include "ch.h"

+#include "hal.h"

+

+

+

+

+

+

+// TODO: defines look in 4492 stm32f10x.h

+

+

+

+

+

+/** The RTCCLK clock source can be either the HSE/128, LSE or LSI clocks. This is selected

+by programming the RTCSEL[1:0] bits in the Backup domain control register (RCC_BDCR).

+This selection

+CANNOT

+be modified without resetting the Backup domain.

+

+The LSE clock is in the Backup domain, whereas the HSE and LSI clocks are not.

+Consequently:

+* If LSE is selected as RTC clock:

+– The RTC continues to work even if the VDD supply is switched off, provided the

+VBAT supply is maintained.

+* If LSI is selected as Auto-Wakeup unit (AWU) clock:

+– The AWU state is not guaranteed if the VDD supply is powered off. Refer to

+Section 6.2.5: LSI clock on page 87 for more details on LSI calibration.

+* If the HSE clock divided by 128 is used as the RTC clock:

+– The RTC state is not guaranteed if the VDD supply is powered off or if the internal

+voltage regulator is powered off (removing power from the 1.8 V domain).

+– The DPB bit (Disable backup domain write protection) in the Power controller

+register must be set to 1 (refer to Section 4.4.1: Power control register

+(PWR_CR)).

+*/

+

+#if HAL_USE_RTC || defined(__DOXYGEN__)

+

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

+/* Driver exported variables.                                                */

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

+

+RTCDriver RTCD;

+

+

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

+/* Driver local variables.                                                   */

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

+

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

+/* Driver local functions.                                                   */

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

+

+/**

+ * @brief   Shared IRQ handler.

+ *

+ * @param[in] rtcp    pointer to a @p RTCDriver object

+ */

+#if RTC_SUPPORTS_CALLBACKS

+

+static void rtc_lld_serve_interrupt(RTCDriver *rtcp){

+  chSysLockFromIsr();

+//TODO: do not forget to reset flags manually

+  if (RTC->CRL & RTC_CRL_SECF){

+    rtcp->config->second_cb(rtcp);

+    RTC->CRL &= ~RTC_CRL_SECF;

+  }

+  if (RTC->CRL & RTC_CRL_ALRF){

+    rtcp->config->alarm_cb(rtcp);

+    RTC->CRL &= ~RTC_CRL_ALRF;

+  }

+  if (RTC->CRL & RTC_CRL_OWF){

+    rtcp->config->overflow_cb(rtcp);

+    RTC->CRL &= ~RTC_CRL_OWF;

+  }

+  chSysUnlockFromIsr();

+}

+#endif /* RTC_SUPPORTS_CALLBACKS */

+

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

+/* Driver interrupt handlers.                                                */

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

+

+/**

+ * @brief   RTC interrupt handler.

+ * @isr

+ */

+#if RTC_SUPPORTS_CALLBACKS

+

+CH_IRQ_HANDLER(RTC_IRQHandler) {

+  CH_IRQ_PROLOGUE();

+  rtc_lld_serve_interrupt(&RTCD);

+  CH_IRQ_EPILOGUE();

+}

+

+#endif /* RTC_SUPPORTS_CALLBACKS */

+

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

+/* Driver exported functions.                                                */

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

+

+/**

+ * @brief   Enable access to registers and initialize RTC if BKP domain

+ *          was previously reseted.

+ */

+void rtc_lld_init(void){

+  RCC->APB1ENR |= (RCC_APB1ENR_PWREN | RCC_APB1ENR_BKPEN);  /* enable clocking */

+  PWR->CR |= PWR_CR_DBP;                                    /* enable access */

+

+  if (!(RCC->BDCR & (RCC_BDCR_RTCEN | RCC_BDCR_LSEON))){    /* BKP domain was reseted */

+    RCC->BDCR |= STM32_RTC_LSE;                             /* select clocking from LSE */

+    RCC->BDCR |= RCC_BDCR_LSEON;                            /* switch LSE on */

+    while(!(RCC->BDCR & RCC_BDCR_LSEON))                    /* wait for stabilization */

+      ;

+    RCC->BDCR |= RCC_BDCR_RTCEN;                            /* run clock */

+  }

+

+  /* 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_RSF);

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

+    ;

+}

+

+/**

+ * @brief     Configure and start interrupt servicing routines.

+ *

+ * @param[in] rtcp    pointer to a @p RTCDriver object

+ * @param[in] rtccfgp pointer to a @p RTCDriver config object

+ */

+#if RTC_SUPPORTS_CALLBACKS

+void rtc_lld_start(RTCDriver *rtcp, RTCConfig *rtccfgp){

+  uint16_t flags = 0;

+

+  NVICEnableVector(RTC_IRQn, CORTEX_PRIORITY_MASK(STM32_RTC_IRQ_PRIORITY));

+

+  rtcp->config = rtccfgp;

+  if (rtcp->config->overflow_cb != NULL){

+    flags |= RTC_CRH_OWIE;

+  }

+  if (rtcp->config->alarm_cb != NULL){

+    flags |= RTC_CRH_ALRIE;

+  }

+  if (rtcp->config->second_cb != NULL){

+    flags |= RTC_CRH_SECIE;

+  }

+

+  RTC->CRH |= flags;

+}

+

+/**

+ * @brief   Disable interrupt servicing routines.

+ */

+void rtc_lld_stop(void){

+  NVICDisableVector(RTC_IRQn);

+  RTC->CRH = 0;

+}

+#endif /* RTC_SUPPORTS_CALLBACKS */

+

+

+

+/**

+ * @brief     Set current time.

+ *

+ * @param[in] tv_sec     time value in UNIX notation.

+ */

+void rtc_lld_set_time(uint32_t tv_sec){

+  uint32_t preload = STM32_LSECLK - 1UL;

+

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

+    ;

+

+  RTC->CRL |= RTC_CRL_CNF;                            /* switch on configure mode */

+  RTC->PRLH = (uint16_t)((preload >> 16) & 0b1111);   /* write preloader */

+  RTC->PRLL = (uint16_t)(preload & 0xFFFF);

+  RTC->CNTH = (uint16_t)((tv_sec >> 16) & 0xFFFF);    /* write time */

+  RTC->CNTL = (uint16_t)(tv_sec & 0xFFFF);

+  RTC->CRL &= ~RTC_CRL_CNF;                           /* switch off configure mode */

+

+  while(!(RTC->CRL & RTC_CRL_RTOFF))                  /* wait for completion */

+    ;

+}

+

+/**

+ * @brief Return current time in UNIX notation.

+ */

+uint32_t rtc_lld_get_sec(void){

+  return ((RTC->CNTH << 16) + RTC->CNTL);

+}

+

+/**

+ * @brief Return fractional part of current time (milliseconds).

+ */

+uint16_t rtc_lld_get_msec(void){

+  uint32_t time_frac = 0;

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

+  return(((STM32_LSECLK - time_frac) * 1000) / STM32_LSECLK);

+}

+

+/**

+ * @brief Set alarm date in UNIX notation.

+ */

+void rtc_lld_set_alarm(uint32_t tv_alarm){

+

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

+    ;

+

+  RTC->CRL |= RTC_CRL_CNF;                            /* switch on configure mode */

+  RTC->ALRH = (uint16_t)((tv_alarm >> 16) & 0xFFFF);  /* write time */

+  RTC->ALRL = (uint16_t)(tv_alarm & 0xFFFF);

+  RTC->CRL &= ~RTC_CRL_CNF;                           /* switch off configure mode */

+

+  while(!(RTC->CRL & RTC_CRL_RTOFF))                  /* wait for completion */

+    ;

+}

+

+/**

+ * @brief Get current alarm date in UNIX notation.

+ * @note  Default value after reset is 0xFFFFFFFF

+ */

+uint32_t rtc_lld_get_alarm(void){

+  return ((RTC->ALRH << 16) + RTC->ALRL);

+}

+

+

+#endif /* HAL_USE_RTC */

+

+/** @} */

diff --git a/os/hal/platforms/STM32/rtc_lld.h b/os/hal/platforms/STM32/rtc_lld.h
new file mode 100644
index 000000000..cf18b664c
--- /dev/null
+++ b/os/hal/platforms/STM32/rtc_lld.h
@@ -0,0 +1,100 @@
+

+/**

+ * @file    STM32/rtc_lld.h

+ * @brief   STM32 RTC subsystem low level driver header.

+ *

+ * @addtogroup RTC

+ * @{

+ */

+

+#ifndef _RTC_LLD_H_

+#define _RTC_LLD_H_

+

+#if HAL_USE_RTC || defined(__DOXYGEN__)

+

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

+/* Driver constants.                                                         */

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

+

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

+/* Driver pre-compile time settings.                                         */

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

+/**

+ * @brief   Switch to TRUE if you need callbacks from RTC. Switch to FALSE

+ *          if you need only time keeping.

+ * @note    Default is true.

+ */

+#if !defined(RTC_SUPPORTS_CALLBACKS) || defined(__DOXYGEN__)

+#define RTC_SUPPORTS_CALLBACKS              TRUE

+#endif

+

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

+/* Derived constants and error checks.                                       */

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

+

+#if HAL_USE_RTC && !STM32_HAS_RTC

+#error "RTC not present in the selected device"

+#endif

+

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

+/* Driver data structures and types.                                         */

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

+/**

+ * @brief Structure representing an RTC driver config.

+ */

+typedef struct {

+  /**

+   * @brief Overflow callback. Set it to NULL if not used.

+   */

+  rtccb_t           overflow_cb;

+

+  /**

+   * @brief Every second callback. Set it to NULL if not used.

+   */

+  rtccb_t           second_cb;

+

+  /**

+   * @brief Alarm callback. Set it to NULL if not used.

+   */

+  rtccb_t           alarm_cb;

+}RTCConfig;

+

+

+/**

+ * @brief Structure representing an RTC driver.

+ */

+struct RTCDriver{

+  /**

+   * @brief Pointer to RCT config.

+   */

+  const RTCConfig       *config;

+};

+

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

+/* Driver macros.                                                            */

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

+

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

+/* External declarations.                                                    */

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

+

+#ifdef __cplusplus

+extern "C" {

+#endif

+  void rtc_lld_init(void);

+#if RTC_SUPPORTS_CALLBACKS

+  void rtc_lld_start(RTCDriver *rtcp, RTCConfig *rtccfgp);

+  void rtc_lld_stop(void);

+#endif /* RTC_SUPPORTS_CALLBACKS */

+  void rtc_lld_set_time(uint32_t tv_sec);

+  uint32_t rtc_lld_get_sec(void);

+  uint16_t rtc_lld_get_msec(void);

+#ifdef __cplusplus

+}

+#endif

+

+

+#endif /* HAL_USE_RTC */

+#endif /* _RTC_LLD_H_ */

+

+/** @} */