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/*
* Copyright (c) 2013 - 2014, Freescale Semiconductor, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* o Redistributions of source code must retain the above copyright notice, this list
* of conditions and the following disclaimer.
*
* o 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.
*
* o Neither the name of Freescale Semiconductor, Inc. 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 "fsl_pit_common.h"
#include "fsl_pit_driver.h"
#include "fsl_clock_manager.h"
#include "fsl_interrupt_manager.h"
/*******************************************************************************
* Variables
******************************************************************************/
/* pit source clock variable which will be updated in PIT_DRV_Init. */
uint64_t pitSourceClock;
/*******************************************************************************
* Code
******************************************************************************/
/*FUNCTION**********************************************************************
*
* Function Name : PIT_DRV_Init
* Description : Initialize PIT module.
* This function must be called before calling all the other PIT driver functions.
* This function un-gates the PIT clock and enables the PIT module. The isRunInDebug
* passed into function will affect all timer channels.
*
*END**************************************************************************/
void PIT_DRV_Init(uint32_t instance, bool isRunInDebug)
{
assert(instance < HW_PIT_INSTANCE_COUNT);
uint32_t baseAddr = g_pitBaseAddr[instance];
/* Un-gate pit clock*/
CLOCK_SYS_EnablePitClock( 0U);
/* Enable PIT module clock*/
PIT_HAL_Enable(baseAddr);
/* Set timer run or stop in debug mode*/
PIT_HAL_SetTimerRunInDebugCmd(baseAddr, isRunInDebug);
/* Finally, update pit source clock frequency.*/
pitSourceClock = CLOCK_SYS_GetPitFreq(0);
}
/*FUNCTION**********************************************************************
*
* Function Name : PIT_DRV_InitChannel
* Description : Initialize PIT channel.
* This function initialize PIT timers by channel. Pass in timer number and its
* config structure. Timers do not start counting by default after calling this
* function. Function PIT_DRV_StartTimer must be called to start timer counting.
* Call PIT_DRV_SetTimerPeriodByUs to re-set the period.
*
*END**************************************************************************/
void PIT_DRV_InitChannel(uint32_t instance, uint32_t channel, const pit_user_config_t * config)
{
assert(instance < HW_PIT_INSTANCE_COUNT);
uint32_t baseAddr = g_pitBaseAddr[instance];
/* Set timer period.*/
PIT_DRV_SetTimerPeriodByUs(instance, channel, config->periodUs);
#if FSL_FEATURE_PIT_HAS_CHAIN_MODE
/* Configure timer chained or not.*/
PIT_HAL_SetTimerChainCmd(baseAddr, channel, config->isTimerChained);
#endif
/* Enable or disable interrupt.*/
PIT_HAL_SetIntCmd(baseAddr, channel, config->isInterruptEnabled);
/* Configure NVIC*/
if (config->isInterruptEnabled)
{
/* Enable PIT interrupt.*/
INT_SYS_EnableIRQ(g_pitIrqId[channel]);
}
}
/*FUNCTION**********************************************************************
*
* Function Name : PIT_DRV_Deinit
* Description : Disable PIT module and gate control
* This function will disable all PIT interrupts and PIT clock. Then gate the
* PIT clock control. pit_init must be called in order to use PIT again.
*
*END**************************************************************************/
void PIT_DRV_Deinit(uint32_t instance)
{
assert(instance < HW_PIT_INSTANCE_COUNT);
uint32_t baseAddr = g_pitBaseAddr[instance];
uint32_t i;
/* Disable all PIT interrupts. */
for (i=0; i < FSL_FEATURE_PIT_TIMER_COUNT; i++)
{
PIT_HAL_SetIntCmd(baseAddr, i, false);
INT_SYS_DisableIRQ(g_pitIrqId[i]);
}
/* Disable PIT module clock*/
PIT_HAL_Disable(baseAddr);
/* Gate PIT clock control*/
CLOCK_SYS_DisablePitClock( 0U);
}
/*FUNCTION**********************************************************************
*
* Function Name : PIT_DRV_StartTimer
* Description : Start timer counting.
* After calling this function, timers load period value, count down to 0 and
* then load the respective start value again. Each time a timer reaches 0,
* it will generate a trigger pulse and set the timeout interrupt flag.
*
*END**************************************************************************/
void PIT_DRV_StartTimer(uint32_t instance, uint32_t channel)
{
assert(instance < HW_PIT_INSTANCE_COUNT);
uint32_t baseAddr = g_pitBaseAddr[instance];
PIT_HAL_StartTimer(baseAddr, channel);
}
/*FUNCTION**********************************************************************
*
* Function Name : PIT_DRV_StopTimer
* Description : Stop timer counting.
* This function will stop every timer counting. Timers will reload their periods
* respectively after calling PIT_DRV_StartTimer next time.
*
*END**************************************************************************/
void PIT_DRV_StopTimer(uint32_t instance, uint32_t channel)
{
assert(instance < HW_PIT_INSTANCE_COUNT);
uint32_t baseAddr = g_pitBaseAddr[instance];
PIT_HAL_StopTimer(baseAddr, channel);
}
/*FUNCTION**********************************************************************
*
* Function Name : PIT_DRV_SetTimerPeriodByUs
* Description : Set timer period in microseconds unit.
* The period range depends on the frequency of PIT source clock. If required
* period is out the range, try to use lifetime timer if applicable.
*
*END**************************************************************************/
void PIT_DRV_SetTimerPeriodByUs(uint32_t instance, uint32_t channel, uint32_t us)
{
assert(instance < HW_PIT_INSTANCE_COUNT);
uint32_t baseAddr = g_pitBaseAddr[instance];
/* Calculate the count value, assign it to timer counter register.*/
uint32_t count = (uint32_t)(us * pitSourceClock / 1000000U - 1U);
PIT_HAL_SetTimerPeriodByCount(baseAddr, channel, count);
}
/*FUNCTION**********************************************************************
*
* Function Name : PIT_DRV_ReadTimerUs
* Description : Read current timer value in microseconds unit.
* This function will return an absolute time stamp in the unit of microseconds.
* One common use of this function is to measure the running time of part of
* code. Just call this function at both the beginning and end of code, the time
* difference between these two time stamp will be the running time (Need to
* make sure the running time will not exceed the timer period). Also, the time
* stamp returned is up-counting.
*
*END**************************************************************************/
uint32_t PIT_DRV_ReadTimerUs(uint32_t instance, uint32_t channel)
{
assert(instance < HW_PIT_INSTANCE_COUNT);
uint32_t baseAddr = g_pitBaseAddr[instance];
/* Get current timer count, and reverse it to up-counting.*/
uint64_t currentTime = (~PIT_HAL_ReadTimerCount(baseAddr, channel));
/* Convert count numbers to microseconds unit.*/
currentTime = (currentTime * 1000000U) / pitSourceClock;
return (uint32_t)currentTime;
}
#if FSL_FEATURE_PIT_HAS_LIFETIME_TIMER
/*FUNCTION**********************************************************************
*
* Function Name : PIT_DRV_SetLifetimeTimerPeriodByUs
* Description : Set lifetime timer period (Timers must be chained).
* Timer 1 must be chained with timer 0 before using lifetime timer. The period
* range is restricted by "period * pitSourceClock < max of an uint64_t integer",
* or it may cause a overflow and is not able to set correct period.
*
*END**************************************************************************/
void PIT_DRV_SetLifetimeTimerPeriodByUs(uint32_t instance, uint64_t us)
{
assert(instance < HW_PIT_INSTANCE_COUNT);
uint32_t baseAddr = g_pitBaseAddr[instance];
uint64_t lifeTimeCount;
/* Calculate the counter value.*/
lifeTimeCount = us * pitSourceClock / 1000000U - 1U;
/* Assign to timers.*/
PIT_HAL_SetTimerPeriodByCount(baseAddr, 0U, (uint32_t)lifeTimeCount);
PIT_HAL_SetTimerPeriodByCount(baseAddr, 1U, (uint32_t)(lifeTimeCount >> 32U));
}
/*FUNCTION**********************************************************************
*
* Function Name : PIT_DRV_ReadLifetimeTimerUs
* Description : Read current lifetime value in microseconds unit.
* Return an absolute time stamp in the unit of microseconds. The time stamp
* value will not exceed the timer period. Also, the timer is up-counting.
*
*END**************************************************************************/
uint64_t PIT_DRV_ReadLifetimeTimerUs(uint32_t instance)
{
assert(instance < HW_PIT_INSTANCE_COUNT);
uint32_t baseAddr = g_pitBaseAddr[instance];
/* Get current lifetime timer count, and reverse it to up-counting.*/
uint64_t currentTime = (~PIT_HAL_ReadLifetimeTimerCount(baseAddr));
/* Convert count numbers to microseconds unit.*/
/* Note: using currentTime * 1000 rather than 1000000 to avoid short time overflow. */
return currentTime = (currentTime * 1000U) / (pitSourceClock / 1000U);
}
#endif /* FSL_FEATURE_PIT_HAS_LIFETIME_TIMER*/
/*******************************************************************************
* EOF
******************************************************************************/
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