mbed-os/targets/TARGET_Silicon_Labs/TARGET_EFM32/rtc_api.c

273 lines
6.4 KiB
C

/***************************************************************************//**
* @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