mbed-os/targets/TARGET_STM/hal_tick_32b.c

108 lines
3.4 KiB
C

/* mbed Microcontroller Library
* Copyright (c) 2006-2016 ARM Limited
*
* 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 "hal_tick.h"
// A 32-bit timer is used
#if !TIM_MST_16BIT
extern TIM_HandleTypeDef TimMasterHandle;
volatile uint32_t PreviousVal = 0;
void us_ticker_irq_handler(void);
void timer_irq_handler(void)
{
// Channel 1 for mbed timeout
if (__HAL_TIM_GET_FLAG(&TimMasterHandle, TIM_FLAG_CC1) == SET) {
if (__HAL_TIM_GET_IT_SOURCE(&TimMasterHandle, TIM_IT_CC1) == SET) {
__HAL_TIM_CLEAR_IT(&TimMasterHandle, TIM_IT_CC1);
us_ticker_irq_handler();
}
}
}
// Overwrite the default ST HAL function (defined as "weak") in order to configure an HW timer
// used for mbed timeouts only (not used for the Systick configuration).
// Additional notes:
// - The default ST HAL_InitTick function initializes the Systick to 1 ms and this is not correct for mbed
// as the mbed Systick as to be configured to 1 us instead.
// - Furthermore the Systick is configured by mbed RTOS directly.
HAL_StatusTypeDef HAL_InitTick(uint32_t TickPriority)
{
RCC_ClkInitTypeDef RCC_ClkInitStruct;
uint32_t PclkFreq;
// Get clock configuration
// Note: PclkFreq contains here the Latency (not used after)
HAL_RCC_GetClockConfig(&RCC_ClkInitStruct, &PclkFreq);
// Get timer clock value
#if TIM_MST_PCLK == 1
PclkFreq = HAL_RCC_GetPCLK1Freq();
#else
PclkFreq = HAL_RCC_GetPCLK2Freq();
#endif
// Enable timer clock
TIM_MST_RCC;
// Reset timer
TIM_MST_RESET_ON;
TIM_MST_RESET_OFF;
// Configure time base
TimMasterHandle.Instance = TIM_MST;
TimMasterHandle.Init.Period = 0xFFFFFFFF;
// TIMxCLK = PCLKx when the APB prescaler = 1 else TIMxCLK = 2 * PCLKx
#if TIM_MST_PCLK == 1
if (RCC_ClkInitStruct.APB1CLKDivider == RCC_HCLK_DIV1) {
#else
if (RCC_ClkInitStruct.APB2CLKDivider == RCC_HCLK_DIV1) {
#endif
TimMasterHandle.Init.Prescaler = (uint16_t)((PclkFreq) / 1000000) - 1; // 1 us tick
} else {
TimMasterHandle.Init.Prescaler = (uint16_t)((PclkFreq * 2) / 1000000) - 1; // 1 us tick
}
TimMasterHandle.Init.ClockDivision = 0;
TimMasterHandle.Init.CounterMode = TIM_COUNTERMODE_UP;
#if !TARGET_STM32L1
TimMasterHandle.Init.RepetitionCounter = 0;
#endif
#ifdef TIM_AUTORELOAD_PRELOAD_DISABLE
TimMasterHandle.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;
#endif
HAL_TIM_OC_Init(&TimMasterHandle);
NVIC_SetVector(TIM_MST_IRQ, (uint32_t)timer_irq_handler);
NVIC_EnableIRQ(TIM_MST_IRQ);
// Channel 1 for mbed timeout
HAL_TIM_OC_Start(&TimMasterHandle, TIM_CHANNEL_1);
// Freeze timer on stop/breakpoint
// Define the FREEZE_TIMER_ON_DEBUG macro in mbed_app.json for example
#if !defined(NDEBUG) && defined(FREEZE_TIMER_ON_DEBUG) && defined(TIM_MST_DBGMCU_FREEZE)
TIM_MST_DBGMCU_FREEZE;
#endif
return HAL_OK;
}
#endif // !TIM_MST_16BIT