John Karatka
mbed
Fork of
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by 
mbed official
Diff: targets/TARGET_STM/lp_ticker.c
- Revision:
- 182:57724642e740
- Parent:
- 181:96ed750bd169
--- a/targets/TARGET_STM/lp_ticker.c Wed Jan 17 15:23:54 2018 +0000
+++ b/targets/TARGET_STM/lp_ticker.c Fri Feb 16 16:09:33 2018 +0000
@@ -27,12 +27,264 @@
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*******************************************************************************
*/
-#include "device.h"
#if DEVICE_LOWPOWERTIMER
#include "rtc_api_hal.h"
+#if MBED_CONF_TARGET_LOWPOWERTIMER_LPTIM
+
+LPTIM_HandleTypeDef LptimHandle;
+
+volatile uint32_t lp_SlaveCounter = 0;
+volatile uint32_t lp_oc_int_part = 0;
+volatile uint16_t lp_TickPeriod_us;
+volatile uint8_t lp_Fired = 0;
+
+static void LPTIM1_IRQHandler(void);
+static void (*irq_handler)(void);
+
+
+void lp_ticker_init(void)
+{
+ /* Check if LPTIM is already configured */
+#if (TARGET_STM32L0)
+ if (READ_BIT(RCC->APB1ENR, RCC_APB1ENR_LPTIM1EN) != RESET) {
+ return;
+ }
+#else
+ if (__HAL_RCC_LPTIM1_IS_CLK_ENABLED()) {
+ return;
+ }
+#endif
+
+ RCC_PeriphCLKInitTypeDef RCC_PeriphCLKInitStruct = {0};
+ RCC_OscInitTypeDef RCC_OscInitStruct = {0};
+
+#if MBED_CONF_TARGET_LSE_AVAILABLE
+
+ /* Enable LSE clock */
+ RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_LSE;
+ RCC_OscInitStruct.LSEState = RCC_LSE_ON;
+ RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
+
+ /* Select the LSE clock as LPTIM peripheral clock */
+ RCC_PeriphCLKInitStruct.PeriphClockSelection = RCC_PERIPHCLK_LPTIM1;
+#if (TARGET_STM32L0)
+ RCC_PeriphCLKInitStruct.LptimClockSelection = RCC_LPTIM1CLKSOURCE_LSE;
+#else
+ RCC_PeriphCLKInitStruct.Lptim1ClockSelection = RCC_LPTIM1CLKSOURCE_LSE;
+#endif
+
+#else /* MBED_CONF_TARGET_LSE_AVAILABLE */
+
+ /* Enable LSI clock */
+ RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_LSI;
+ RCC_OscInitStruct.LSIState = RCC_LSI_ON;
+ RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
+
+ /* Select the LSI clock as LPTIM peripheral clock */
+ RCC_PeriphCLKInitStruct.PeriphClockSelection = RCC_PERIPHCLK_LPTIM1;
+#if (TARGET_STM32L0)
+ RCC_PeriphCLKInitStruct.LptimClockSelection = RCC_LPTIM1CLKSOURCE_LSI;
+#else
+ RCC_PeriphCLKInitStruct.Lptim1ClockSelection = RCC_LPTIM1CLKSOURCE_LSI;
+#endif
+
+#endif /* MBED_CONF_TARGET_LSE_AVAILABLE */
+
+ if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK) {
+ error("HAL_RCC_OscConfig ERROR\n");
+ return;
+ }
+
+ if (HAL_RCCEx_PeriphCLKConfig(&RCC_PeriphCLKInitStruct) != HAL_OK) {
+ error("HAL_RCCEx_PeriphCLKConfig ERROR\n");
+ return;
+ }
+
+ __HAL_RCC_LPTIM1_CLK_ENABLE();
+ __HAL_RCC_LPTIM1_FORCE_RESET();
+ __HAL_RCC_LPTIM1_RELEASE_RESET();
+
+ /* Initialize the LPTIM peripheral */
+ LptimHandle.Instance = LPTIM1;
+ LptimHandle.State = HAL_LPTIM_STATE_RESET;
+ LptimHandle.Init.Clock.Source = LPTIM_CLOCKSOURCE_APBCLOCK_LPOSC;
+
+ /* Prescaler impact:
+ tick period = Prescaler division factor / LPTIM clock
+ Example with LPTIM clock = 32768 Hz LSE
+ Prescaler = LPTIM_PRESCALER_DIV1 => lp_TickPeriod_us = 31us => 2s with 16b timer
+ Prescaler = LPTIM_PRESCALER_DIV2 => lp_TickPeriod_us = 61us => 4s with 16b timer
+ Prescaler = LPTIM_PRESCALER_DIV4 => lp_TickPeriod_us = 122us => 8s with 16b timer
+ Prescaler = LPTIM_PRESCALER_DIV8 => lp_TickPeriod_us = 244us => 16s with 16b timer
+ Prescaler = LPTIM_PRESCALER_DIV16 => lp_TickPeriod_us = 488us => 32s with 16b timer
+ Prescaler = LPTIM_PRESCALER_DIV32 => lp_TickPeriod_us = 976us => 64s with 16b timer
+ Prescaler = LPTIM_PRESCALER_DIV64 => lp_TickPeriod_us = 1.9ms => 128s with 16b timer
+ Prescaler = LPTIM_PRESCALER_DIV128 => lp_TickPeriod_us = 3.9ms => 256s with 16b timer
+ */
+ LptimHandle.Init.Clock.Prescaler = LPTIM_PRESCALER_DIV2;
+ lp_TickPeriod_us = 2 * 1000000 / RTC_CLOCK;
+
+ LptimHandle.Init.Trigger.Source = LPTIM_TRIGSOURCE_SOFTWARE;
+ LptimHandle.Init.OutputPolarity = LPTIM_OUTPUTPOLARITY_HIGH;
+ LptimHandle.Init.UpdateMode = LPTIM_UPDATE_IMMEDIATE;
+ LptimHandle.Init.CounterSource = LPTIM_COUNTERSOURCE_INTERNAL;
+#if (TARGET_STM32L4)
+ LptimHandle.Init.Input1Source = LPTIM_INPUT1SOURCE_GPIO;
+ LptimHandle.Init.Input2Source = LPTIM_INPUT2SOURCE_GPIO;
+#endif /* TARGET_STM32L4 */
+
+ if (HAL_LPTIM_Init(&LptimHandle) != HAL_OK) {
+ error("HAL_LPTIM_Init ERROR\n");
+ return;
+ }
+
+ NVIC_SetVector(LPTIM1_IRQn, (uint32_t)LPTIM1_IRQHandler);
+ NVIC_EnableIRQ(LPTIM1_IRQn);
+
+#if !(TARGET_STM32L4)
+ /* EXTI lines are not configured by default */
+ __HAL_LPTIM_WAKEUPTIMER_EXTI_ENABLE_IT();
+ __HAL_LPTIM_WAKEUPTIMER_EXTI_ENABLE_RISING_EDGE();
+#endif
+
+ __HAL_LPTIM_ENABLE_IT(&LptimHandle, LPTIM_IT_ARRM);
+ __HAL_LPTIM_ENABLE_IT(&LptimHandle, LPTIM_IT_CMPM);
+ __HAL_LPTIM_ENABLE_IT(&LptimHandle, LPTIM_IT_CMPOK);
+ HAL_LPTIM_Counter_Start(&LptimHandle, 0xFFFF);
+}
+
+static void LPTIM1_IRQHandler(void)
+{
+ LptimHandle.Instance = LPTIM1;
+
+ if (lp_Fired) {
+ lp_Fired = 0;
+ if (irq_handler) {
+ irq_handler();
+ }
+ }
+
+ /* Compare match interrupt */
+ if (__HAL_LPTIM_GET_FLAG(&LptimHandle, LPTIM_FLAG_CMPM) != RESET) {
+ if (__HAL_LPTIM_GET_IT_SOURCE(&LptimHandle, LPTIM_IT_CMPM) != RESET) {
+ /* Clear Compare match flag */
+ __HAL_LPTIM_CLEAR_FLAG(&LptimHandle, LPTIM_FLAG_CMPM);
+
+ if (lp_oc_int_part > 0) {
+ lp_oc_int_part--;
+ } else {
+ if (irq_handler) {
+ irq_handler();
+ }
+ }
+ }
+ }
+
+ /* Compare write interrupt */
+ if (__HAL_LPTIM_GET_FLAG(&LptimHandle, LPTIM_FLAG_CMPOK) != RESET) {
+ if (__HAL_LPTIM_GET_IT_SOURCE(&LptimHandle, LPTIM_IT_CMPOK) != RESET) {
+ /* Clear Compare write flag */
+ __HAL_LPTIM_CLEAR_FLAG(&LptimHandle, LPTIM_FLAG_CMPOK);
+ }
+ }
+
+ /* Autoreload match interrupt */
+ if (__HAL_LPTIM_GET_FLAG(&LptimHandle, LPTIM_FLAG_ARRM) != RESET) {
+ if (__HAL_LPTIM_GET_IT_SOURCE(&LptimHandle, LPTIM_IT_ARRM) != RESET) {
+ /* Clear Autoreload match flag */
+ __HAL_LPTIM_CLEAR_FLAG(&LptimHandle, LPTIM_FLAG_ARRM);
+ lp_SlaveCounter++;
+ }
+ }
+
+#if !(TARGET_STM32L4)
+ __HAL_LPTIM_WAKEUPTIMER_EXTI_CLEAR_FLAG();
+#endif
+}
+
+
+uint32_t lp_ticker_read_TickCounter(void)
+{
+ uint16_t cntH_old, cntH, cntL;
+
+ LptimHandle.Instance = LPTIM1;
+
+ /* same algo as us_ticker_read in us_ticker_16b.c */
+ do {
+ cntH_old = lp_SlaveCounter;
+ if (__HAL_LPTIM_GET_FLAG(&LptimHandle, LPTIM_FLAG_ARRM) == SET) {
+ cntH_old += 1;
+ }
+ cntL = LPTIM1->CNT;
+ cntH = lp_SlaveCounter;
+ if (__HAL_LPTIM_GET_FLAG(&LptimHandle, LPTIM_FLAG_ARRM) == SET) {
+ cntH += 1;
+ }
+ } while (cntH_old != cntH);
+ uint32_t lp_time = (uint32_t)(cntH << 16 | cntL);
+ return lp_time;
+}
+
+uint32_t lp_ticker_read(void)
+{
+ lp_ticker_init();
+ return lp_ticker_read_TickCounter() * (uint32_t)lp_TickPeriod_us;
+}
+
+void lp_ticker_set_interrupt(timestamp_t timestamp)
+{
+ // Disable IRQs
+ core_util_critical_section_enter();
+
+ uint32_t timestamp_TickCounter = timestamp / (uint32_t)lp_TickPeriod_us;
+
+ LptimHandle.Instance = LPTIM1;
+ irq_handler = (void (*)(void))lp_ticker_irq_handler;
+
+ __HAL_LPTIM_CLEAR_FLAG(&LptimHandle, LPTIM_FLAG_CMPOK);
+ __HAL_LPTIM_CLEAR_FLAG(&LptimHandle, LPTIM_FLAG_CMPM);
+ __HAL_LPTIM_COMPARE_SET(&LptimHandle, timestamp_TickCounter & 0xFFFF);
+
+ /* CMPOK is set by hardware to inform application that the APB bus write operation to the LPTIM_CMP register has been successfully completed */
+ while (__HAL_LPTIM_GET_FLAG(&LptimHandle, LPTIM_FLAG_CMPOK) == RESET) {
+ }
+
+ /* same algo as us_ticker_set_interrupt in us_ticker_16b.c */
+ uint32_t current_time_TickCounter = lp_ticker_read_TickCounter();
+ uint32_t delta = timestamp_TickCounter - current_time_TickCounter;
+ lp_oc_int_part = (delta - 1) >> 16;
+ if ( ((delta - 1) & 0xFFFF) >= 0x8000 &&
+ __HAL_LPTIM_GET_FLAG(&LptimHandle, LPTIM_FLAG_CMPM) == SET ) {
+ ++lp_oc_int_part;
+ }
+
+ // Enable IRQs
+ core_util_critical_section_exit();
+}
+
+void lp_ticker_fire_interrupt(void)
+{
+ lp_Fired = 1;
+ NVIC_SetPendingIRQ(LPTIM1_IRQn);
+}
+
+void lp_ticker_disable_interrupt(void)
+{
+ LptimHandle.Instance = LPTIM1;
+ __HAL_LPTIM_DISABLE_IT(&LptimHandle, LPTIM_IT_CMPM);
+}
+
+void lp_ticker_clear_interrupt(void)
+{
+ LptimHandle.Instance = LPTIM1;
+ __HAL_LPTIM_CLEAR_FLAG(&LptimHandle, LPTIM_FLAG_CMPM);
+}
+
+#else /* MBED_CONF_TARGET_LOWPOWERTIMER_LPTIM */
+
void lp_ticker_init(void)
{
rtc_init();
@@ -40,15 +292,8 @@
uint32_t lp_ticker_read(void)
{
- uint32_t usecs = 0;
- time_t time = 0;
-
- do {
- time = rtc_read();
- usecs = rtc_read_subseconds();
- } while (time != rtc_read());
-
- return (time * 1000000) + usecs;
+ uint32_t usecs = rtc_read_us();
+ return usecs;
}
void lp_ticker_set_interrupt(timestamp_t timestamp)
@@ -74,4 +319,6 @@
NVIC_ClearPendingIRQ(RTC_WKUP_IRQn);
}
+#endif /* MBED_CONF_TARGET_LOWPOWERTIMER_LPTIM */
+
#endif /* DEVICE_LOWPOWERTIMER */