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