FreeRTOS/Demo/CORTEX_M7_SAMV71_Xplained_AtmelStudio/libchip_samv7/source/timetick.c

/* ----------------------------------------------------------------------------
 *         SAM Software Package License 
 * ----------------------------------------------------------------------------
 * Copyright (c) 2014, Atmel Corporation
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * - Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the disclaimer below.
 *
 * Atmel's name may not be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * DISCLAIMER: THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
 * DISCLAIMED. IN NO EVENT SHALL ATMEL 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.
 * ----------------------------------------------------------------------------
 */

/**
 *  \file
 *  Implement the System Timer.
 */

/*----------------------------------------------------------------------------
 *         Headers
 *----------------------------------------------------------------------------*/

#include "board.h"
#include <assert.h>
/*----------------------------------------------------------------------------
 *         Local variables
 *----------------------------------------------------------------------------*/
#define MAX_TIMER   4
/** Tick Counter united by ms */
static volatile uint32_t _dwTickCount = 0 ;
static uint8_t SysTickConfigured = 0 ;

static volatile uint32_t _dwTickTimer = 0 ;
static TimeEvent *pTimeEventList = 0;

SyTickDelayCounter_t DelayTimer;

/*----------------------------------------------------------------------------
 *         Exported Functions
 *----------------------------------------------------------------------------*/


/**
 *  \brief Handler for System Tick interrupt.
 *
 *  Process System Tick Event
 *  Increments the time-stamp counter.
 */
void SysTick_Handler( void )
{
	 TimeEvent *pEvent;
	pEvent = pTimeEventList;
	_dwTickCount ++;
	if(_dwTickTimer)
	  _dwTickTimer --;
	while(pEvent) {
		if(pEvent->time_start && pEvent->occur == 0) {
			pEvent->time_tick--;
			if(pEvent->time_tick == 0) {
			   pEvent->time_start = 0;
			   pEvent->occur = 1;
			}
		}
		pEvent = pEvent->pNextEvent;
	}
}

void SetTimeEvent(TimeEvent* pEvent)
{
    pTimeEventList = pEvent;
}

/**
 *  \brief Configures the System Timer.
 *  Systick interrupt handler will generates 1ms interrupt and increase a
 *  tickCount.
 *  \note IRQ handler must be configured before invoking this function.
 */
uint32_t TimeTick_Configure( void )
{
	uint8_t Mdiv_Val;
	uint32_t Pck;
	_dwTickCount = 0 ;

	TRACE_INFO( "Configure system tick to get 1ms tick period.\n\r" ) ;
	/* check if there is MDIV value */
	Mdiv_Val = ( (PMC->PMC_MCKR & PMC_MCKR_MDIV_Msk) >> PMC_MCKR_MDIV_Pos);

	if(Mdiv_Val == 0) {
	  Pck = BOARD_MCK;
	} else if(Mdiv_Val == 3 ) {
	  Pck = BOARD_MCK * Mdiv_Val;
	} else {
	  Pck = BOARD_MCK * (Mdiv_Val*2);
	}

	 DelayTimer.pTimer1 = NULL; DelayTimer.pTimer1=NULL;
	/* Configure SysTick for 1 ms. */
	if ( SysTick_Config( Pck/1000 ) ) {
		TRACE_ERROR("SysTick configuration error\n\r" ) ;
		SysTickConfigured = 0;
		return 1;
	}
	SysTickConfigured = 1;
	return 0;
}

/**
 * \brief Get Delayed number of tick
 * \param startTick Start tick point.
 * \param endTick   End tick point.
 */
uint32_t GetDelayInTicks(uint32_t startTick, uint32_t endTick)
{
	assert(SysTickConfigured);
	
	if (endTick >= startTick) return (endTick - startTick);
	return (endTick + (0xFFFFFFFF - startTick) + 1);
	
}

/**
 * \brief Get Delayed number of tick
 * \param startTick Start tick point.
 * \param endTick   End tick point.
 */
uint32_t GetTicks(void)
{
	assert(SysTickConfigured);
	
	return _dwTickCount;
}

/**
 *  \brief Sync Wait for several ms
 *  \param dwMs    Waiting time in ms.
 */
void Wait( volatile uint32_t dwMs )
{
	uint32_t dwStart , dwEnd;
	
	assert(SysTickConfigured);
	
	dwStart = _dwTickCount ;
	dwEnd = _dwTickCount;
	while(GetDelayInTicks(dwStart, dwEnd) < dwMs ){
		dwEnd = _dwTickCount;
	}
}

/**
 *  \brief Sync Sleep for several ms
 *  \param dwMs    Sleeping time in ms.
 */
void Sleep( volatile uint32_t dwMs )
{
	uint32_t dwStart , dwEnd;
	 
	assert(SysTickConfigured);
   
	__ASM("CPSIE   I");
	dwStart = _dwTickCount ;
	dwEnd = _dwTickCount;
	do {
		if (GetDelayInTicks(dwStart, dwEnd) < dwMs ) {
			break ;
		}
		dwEnd = _dwTickCount;
		__ASM("WFI");
	} while( 1 ) ;
}