/**
  ******************************************************************************
  * @file    hal_tick.c
  * @author  MCD Application Team
  * @brief   Initialization of HAL tick
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; COPYRIGHT 2016 STMicroelectronics</center></h2>
  *
  * Redistribution and use in source and binary forms, with or without modification,
  * are permitted provided that the following conditions are met:
  *   1. Redistributions of source code must retain the above copyright notice,
  *      this list of conditions and the following disclaimer.
  *   2. Redistributions in binary form must reproduce the above copyright notice,
  *      this list of conditions and the following disclaimer in the documentation
  *      and/or other materials provided with the distribution.
  *   3. Neither the name of STMicroelectronics nor the names of its contributors
  *      may be used to endorse or promote products derived from this software
  *      without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
  ******************************************************************************
  */
#include "hal_tick.h"

// 0=NO, 1=PG6 toggles at each tick
#define DEBUG_TICK 0

TIM_HandleTypeDef TimMasterHandle;
uint32_t PreviousVal = 0;

void HAL_IncTick(void);
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();
        }
    }

    // Channel 2 for HAL tick
    if (__HAL_TIM_GET_FLAG(&TimMasterHandle, TIM_FLAG_CC2) == SET) {
        if (__HAL_TIM_GET_IT_SOURCE(&TimMasterHandle, TIM_IT_CC2) == SET) {
            __HAL_TIM_CLEAR_IT(&TimMasterHandle, TIM_IT_CC2);
            uint32_t val = __HAL_TIM_GetCounter(&TimMasterHandle);
            if ((val - PreviousVal) >= HAL_TICK_DELAY) {
                // Increment HAL variable
                HAL_IncTick();
                // Prepare next interrupt
                __HAL_TIM_SetCompare(&TimMasterHandle, TIM_CHANNEL_2, val + HAL_TICK_DELAY);
                PreviousVal = val;
#if DEBUG_TICK > 0
                HAL_GPIO_TogglePin(GPIOG, GPIO_PIN_6);
#endif
            }
        }
    }
}

// Reconfigure the HAL tick using a standard timer instead of systick.
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 TIM5 clock value
    PclkFreq = HAL_RCC_GetPCLK1Freq();

    // 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 (RCC_ClkInitStruct.APB1CLKDivider == RCC_HCLK_DIV1)
      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;
    TimMasterHandle.Init.RepetitionCounter = 0;
    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);

    // Channel 2 for HAL tick
    HAL_TIM_OC_Start(&TimMasterHandle, TIM_CHANNEL_2);
    PreviousVal = __HAL_TIM_GetCounter(&TimMasterHandle);
    __HAL_TIM_SetCompare(&TimMasterHandle, TIM_CHANNEL_2, PreviousVal + HAL_TICK_DELAY);
    __HAL_TIM_ENABLE_IT(&TimMasterHandle, TIM_IT_CC2);

#if DEBUG_TICK > 0
    __GPIOG_CLK_ENABLE();
    GPIO_InitTypeDef GPIO_InitStruct;
    GPIO_InitStruct.Pin = GPIO_PIN_6;
    GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
    GPIO_InitStruct.Pull = GPIO_PULLUP;
    GPIO_InitStruct.Speed = GPIO_SPEED_FAST;
    HAL_GPIO_Init(GPIOG, &GPIO_InitStruct);
#endif

    return HAL_OK;
}

/**
  * @}
  */

/**
  * @}
  */
  
/**
  * @}
  */    
/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/