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Diff: targets/hal/TARGET_Silicon_Labs/TARGET_EFM32/rtc_api.c
- Revision:
- 0:9b334a45a8ff
- Child:
- 50:a417edff4437
diff -r 000000000000 -r 9b334a45a8ff targets/hal/TARGET_Silicon_Labs/TARGET_EFM32/rtc_api.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/targets/hal/TARGET_Silicon_Labs/TARGET_EFM32/rtc_api.c Thu Oct 01 15:25:22 2015 +0300 @@ -0,0 +1,172 @@ +/***************************************************************************//** + * @file rtc_api.c + ******************************************************************************* + * @section License + * <b>(C) Copyright 2015 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 "device.h" +#if DEVICE_RTC + +#include "rtc_api.h" +#include "rtc_api_HAL.h" +#include "em_cmu.h" +#include "em_rtc.h" +#include "sleep_api.h" +#include "sleepmodes.h" + +static bool rtc_inited = false; +static time_t time_base = 0; +static uint32_t useflags = 0; +static uint32_t time_extend = 0; + +static void (*comp0_handler)(void) = NULL; + +#define RTC_LEAST_ACTIVE_SLEEPMODE EM2 +#define RTC_NUM_BITS (24) + +void RTC_IRQHandler(void) +{ + uint32_t flags; + flags = RTC_IntGet(); + if (flags & RTC_IF_OF) { + RTC_IntClear(RTC_IF_OF); + /* RTC has overflowed (24 bits). Use time_extend as software counter for 32 more bits. */ + time_extend += 1; + } + if (flags & RTC_IF_COMP0) { + RTC_IntClear(RTC_IF_COMP0); + if (comp0_handler != NULL) { + comp0_handler(); + } + } +} + +uint32_t rtc_get_32bit(void) +{ + return (RTC_CounterGet() + (time_extend << RTC_NUM_BITS)); +} + +uint64_t rtc_get_full(void) +{ + uint64_t ticks = 0; + ticks += time_extend; + ticks = ticks << RTC_NUM_BITS; + ticks += RTC_CounterGet(); + return ticks; +} + +void rtc_set_comp0_handler(uint32_t handler) +{ + comp0_handler = (void (*)(void)) handler; +} + +void rtc_init(void) +{ + /* Register that the RTC is used for timekeeping. */ + rtc_init_real(RTC_INIT_RTC); +} + + +void rtc_init_real(uint32_t flags) +{ + useflags |= flags; + + if (!rtc_inited) { + CMU_ClockEnable(cmuClock_RTC, true); + + /* Enable clock to the interface of the low energy modules */ + CMU_ClockEnable(cmuClock_CORELE, true); + + /* Scale clock to save power */ + CMU_ClockDivSet(cmuClock_RTC, RTC_CLOCKDIV); + + /* Initialize RTC */ + RTC_Init_TypeDef init = RTC_INIT_DEFAULT; + init.enable = 1; + /* Don't use compare register 0 as top value */ + init.comp0Top = 0; + + /* Enable Interrupt from RTC */ + RTC_IntEnable(RTC_IEN_OF); + NVIC_EnableIRQ(RTC_IRQn); + NVIC_SetVector(RTC_IRQn, (uint32_t)RTC_IRQHandler); + + /* Initialize */ + RTC_Init(&init); + + blockSleepMode(RTC_LEAST_ACTIVE_SLEEPMODE); + rtc_inited = true; + } +} + +void rtc_free(void) +{ + rtc_free_real(RTC_INIT_RTC); +} + +void rtc_free_real(uint32_t flags) +{ + /* Clear use flag */ + useflags &= ~flags; + + /* Disable the RTC if it was inited and is no longer in use by anyone. */ + if (rtc_inited && (useflags == 0)) { + NVIC_DisableIRQ(RTC_IRQn); + RTC_Reset(); + CMU_ClockEnable(cmuClock_RTC, false); + unblockSleepMode(RTC_LEAST_ACTIVE_SLEEPMODE); + rtc_inited = false; + } +} + +int rtc_isenabled(void) +{ + return rtc_inited; +} + +time_t rtc_read(void) +{ + return (time_t) (rtc_get_full() >> RTC_FREQ_SHIFT) + time_base; +} + +time_t rtc_read_uncompensated(void) +{ + return (time_t) (rtc_get_full() >> RTC_FREQ_SHIFT); +} + +void rtc_write(time_t t) +{ + /* We have to check that the RTC did not tick while doing this. */ + /* If the RTC ticks we just redo this. */ + uint32_t time; + do { + time = rtc_read_uncompensated(); + time_base = t - time; + } while (time != rtc_read_uncompensated()); +} + +#endif