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Diff: targets/TARGET_Silicon_Labs/TARGET_EFM32/rtc_api.c
- Revision:
- 149:156823d33999
- Parent:
- 144:ef7eb2e8f9f7
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/targets/TARGET_Silicon_Labs/TARGET_EFM32/rtc_api.c Fri Oct 28 11:17:30 2016 +0100 @@ -0,0 +1,272 @@ +/***************************************************************************//** + * @file rtc_api.c + ******************************************************************************* + * @section License + * <b>(C) Copyright 2015 Silicon Labs, http://www.silabs.com</b> + ******************************************************************************* + * + * SPDX-License-Identifier: Apache-2.0 + * + * 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. + * + ******************************************************************************/ + +#include "device.h" +#if DEVICE_RTC + +#include "rtc_api.h" +#include "rtc_api_HAL.h" +#include "em_cmu.h" +#include "sleep_api.h" +#include "sleepmodes.h" + +#if (defined RTC_COUNT) && (RTC_COUNT > 0) +#include "em_rtc.h" +#endif + +#if (defined RTCC_COUNT) && (RTCC_COUNT > 0) +#include "em_rtcc.h" +#endif + +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; + +#ifndef RTCC_COUNT + +/* Using RTC API */ + +#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) +{ + uint32_t pending = (RTC_IntGet() & RTC_IF_OF) ? 1 : 0; + return (RTC_CounterGet() + ((time_extend + pending) << 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_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_SetVector(RTC_IRQn, (uint32_t)RTC_IRQHandler); + NVIC_EnableIRQ(RTC_IRQn); + + /* 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; + } +} + +#else + +/* Using RTCC API */ + +#define RTCC_LEAST_ACTIVE_SLEEPMODE EM2 +#define RTCC_NUM_BITS (32) + +void RTCC_IRQHandler(void) +{ + uint32_t flags; + flags = RTCC_IntGet(); + + if (flags & RTCC_IF_OF) { + RTCC_IntClear(RTCC_IF_OF); + /* RTC has overflowed (32 bits). Use time_extend as software counter for 32 more bits. */ + time_extend += 1; + } + + if (flags & RTCC_IF_CC0) { + RTCC_IntClear(RTCC_IF_CC0); + if (comp0_handler != NULL) { + comp0_handler(); + } + } +} + +uint32_t rtc_get_32bit(void) +{ + return RTCC_CounterGet(); +} + +uint64_t rtc_get_full(void) +{ + uint64_t ticks = 0; + ticks += time_extend; + ticks = ticks << RTCC_NUM_BITS; + ticks += RTCC_CounterGet(); + return ticks; +} + +void rtc_init_real(uint32_t flags) +{ + useflags |= flags; + + if (!rtc_inited) { + CMU_ClockEnable(cmuClock_RTCC, true); + + /* Enable clock to the interface of the low energy modules */ + CMU_ClockEnable(cmuClock_CORELE, true); + + /* Initialize RTC */ + RTCC_Init_TypeDef init = RTCC_INIT_DEFAULT; + init.enable = 1; + init.precntWrapOnCCV0 = false; + init.cntWrapOnCCV1 = false; +#if RTC_CLOCKDIV_INT == 8 + init.presc = rtccCntPresc_8; +#else +#error invalid prescaler value RTC_CLOCKDIV_INT +#endif + + /* Enable Interrupt from RTC */ + RTCC_IntEnable(RTCC_IEN_OF); + NVIC_SetVector(RTCC_IRQn, (uint32_t)RTCC_IRQHandler); + NVIC_EnableIRQ(RTCC_IRQn); + + /* Initialize */ + RTCC_Init(&init); + + blockSleepMode(RTCC_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(RTCC_IRQn); + RTCC_Reset(); + CMU_ClockEnable(cmuClock_RTCC, false); + unblockSleepMode(RTCC_LEAST_ACTIVE_SLEEPMODE); + rtc_inited = false; + } +} + +#endif /* RTCC_COUNT */ + +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); +} + +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 != (uint32_t)rtc_read_uncompensated()); +} + +#endif