// Copyright (c) 2017-2022, Mudita Sp. z.o.o. All rights reserved.
// For licensing, see https://github.com/mudita/MuditaOS/LICENSE.md
/* Compiler includes. */
#if defined(__ICCARM__)
#include <intrinsics.h>
#endif
/* Scheduler includes. */
#include "FreeRTOS.h"
#include "task.h"
#include "fsl_tickless_generic.h"
#if configUSE_TICKLESS_IDLE == 2
#include "fsl_gpt.h"
#include "fsl_gpc.h"
#else
#include "fsl_common.h"
#endif
extern uint32_t SystemCoreClock; /* in Kinetis SDK, this contains the system core clock speed */
/*
* GPT timer base address and interrupt number
*/
#if configUSE_TICKLESS_IDLE == 2
static GPT_Type *vPortGetGptBase(void)
{
return GPT1;
}
/*!
* @brief Fuction of GPT timer.
*
* This function to return GPT timer interrupt number
*/
static IRQn_Type vPortGetGptIrqn(void)
{
return GPT1_IRQn;
}
#endif /* configUSE_TICKLESS_IDLE */
/*-----------------------------------------------------------*/
/*
* The number of SysTick increments that make up one tick period.
*/
#if configUSE_TICKLESS_IDLE == 2
static uint32_t ulTimerCountsForOneTick = 0;
#endif /* configUSE_TICKLESS_IDLE */
/*
* The maximum number of tick periods that can be suppressed is limited by the
* 24 bit resolution of the SysTick timer.
*/
#if configUSE_TICKLESS_IDLE == 2
static uint32_t xMaximumPossibleSuppressedTicks = 0;
#endif /* configUSE_TICKLESS_IDLE */
/*
* The number of GPT increments that make up one tick period.
*/
#if configUSE_TICKLESS_IDLE == 2
static uint32_t ulLPTimerCountsForOneTick = 0;
#endif /* configUSE_TICKLESS_IDLE */
/*
* The flag of GPT is occurs or not.
*/
#if configUSE_TICKLESS_IDLE == 2
static volatile bool ulLPTimerInterruptFired = false;
#endif /* configUSE_TICKLESS_IDLE */
#if configUSE_TICKLESS_IDLE == 2
void vPortGptIsr(void)
{
ulLPTimerInterruptFired = true;
/* Clear interrupt flag.*/
GPT_ClearStatusFlags(GPT1, kGPT_OutputCompare1Flag);
}
/*!
* @brief Interrupt service fuction of GPT timer.
*
* This function to call low power timer ISR
*/
void GPT1_IRQHandler(void)
{
vPortGptIsr();
}
void vPortSuppressTicksAndSleep(TickType_t xExpectedIdleTime)
{
uint32_t ulReloadValue, ulCompleteTickPeriods;
TickType_t xModifiableIdleTime;
GPT_Type *pxGptBase;
pxGptBase = vPortGetGptBase();
/* Make sure the SysTick reload value does not overflow the counter. */
if (xExpectedIdleTime > xMaximumPossibleSuppressedTicks) {
xExpectedIdleTime = xMaximumPossibleSuppressedTicks;
}
if (xExpectedIdleTime == 0) {
return;
}
/* Calculate the reload value required to wait xExpectedIdleTime
tick periods. -1 is used because this code will execute part way
through one of the tick periods. */
ulReloadValue = (ulLPTimerCountsForOneTick * (xExpectedIdleTime - 1UL));
/* Stop the GPT and systick momentarily. The time the GPT and systick is stopped for
is accounted for as best it can be, but using the tickless mode will
inevitably result in some tiny drift of the time maintained by the
kernel with respect to calendar time. */
GPT_StopTimer(pxGptBase);
portNVIC_SYSTICK_CTRL_REG &= ~portNVIC_SYSTICK_ENABLE_BIT;
/* Enter a critical section but don't use the taskENTER_CRITICAL()
method as that will mask interrupts that should exit sleep mode. */
__disable_irq();
__DSB();
__ISB();
/* If a context switch is pending or a task is waiting for the scheduler
to be unsuspended then abandon the low power entry. */
if (eTaskConfirmSleepModeStatus() == eAbortSleep) {
/* Restart from whatever is left in the count register to complete
this tick period. */
portNVIC_SYSTICK_LOAD_REG = portNVIC_SYSTICK_CURRENT_VALUE_REG;
/* Restart SysTick. */
portNVIC_SYSTICK_CTRL_REG |= portNVIC_SYSTICK_ENABLE_BIT;
/* Reset the reload register to the value required for normal tick
periods. */
portNVIC_SYSTICK_LOAD_REG = ulTimerCountsForOneTick - 1UL;
/* Re-enable interrupts - see comments above __disable_irq()
call above. */
__enable_irq();
}
else {
/* Set the new reload value. */
GPT_SetOutputCompareValue(pxGptBase, kGPT_OutputCompare_Channel1, ulReloadValue);
/* Enable GPT. */
GPT_StartTimer(pxGptBase);
/* Sleep until something happens. configPRE_SLEEP_PROCESSING() can
set its parameter to 0 to indicate that its implementation contains
its own wait for interrupt or wait for event instruction, and so wfi
should not be executed again. However, the original expected idle
time variable must remain unmodified, so a copy is taken. */
xModifiableIdleTime = xExpectedIdleTime;
configPRE_SLEEP_PROCESSING(xModifiableIdleTime);
if (xModifiableIdleTime > 0) {
__DSB();
__WFI();
__ISB();
}
configPOST_SLEEP_PROCESSING(xExpectedIdleTime);
ulLPTimerInterruptFired = false;
/* Re-enable interrupts - see comments above __disable_irq()
call above. */
__enable_irq();
__NOP();
if (ulLPTimerInterruptFired) {
/* The tick interrupt handler will already have pended the tick
processing in the kernel. As the pending tick will be
processed as soon as this function exits, the tick value
maintained by the tick is stepped forward by one less than the
time spent waiting. */
ulCompleteTickPeriods = xExpectedIdleTime - 1UL;
ulLPTimerInterruptFired = false;
}
else {
/* Something other than the tick interrupt ended the sleep.
Work out how long the sleep lasted rounded to complete tick
periods (not the ulReload value which accounted for part
ticks). */
ulCompleteTickPeriods = (GPT_GetCurrentTimerCount(pxGptBase)) / ulLPTimerCountsForOneTick;
}
/* Stop GPT when CPU waked up then set portNVIC_SYSTICK_LOAD_REG back to its standard
value. The critical section is used to ensure the tick interrupt
can only execute once in the case that the reload register is near
zero. */
GPT_StopTimer(pxGptBase);
portENTER_CRITICAL();
{
portNVIC_SYSTICK_CTRL_REG |= portNVIC_SYSTICK_ENABLE_BIT;
vTaskStepTick(ulCompleteTickPeriods);
portNVIC_SYSTICK_LOAD_REG = ulTimerCountsForOneTick - 1UL;
}
portEXIT_CRITICAL();
}
}
#endif /* #if configUSE_TICKLESS_IDLE */
/*
* Setup the systick timer to generate the tick interrupts at the required
* frequency.
*/
void vPortSetupTimerInterrupt(void)
{
/* Calculate the constants required to configure the tick interrupt. */
#if configUSE_TICKLESS_IDLE == 2
gpt_config_t gptConfig;
GPT_GetDefaultConfig(&gptConfig);
gptConfig.clockSource = kGPT_ClockSource_LowFreq; /* 32K RTC OSC */
// gptConfig.enableMode = false; /* Don't keep counter when stop */
gptConfig.enableMode = true; /* Keep counter when stop */
gptConfig.enableRunInDoze = true;
/* Initialize GPT module */
GPT_Init(vPortGetGptBase(), &gptConfig);
/* Divide GPT clock source frequency by 1 inside GPT module */
GPT_SetClockDivider(vPortGetGptBase(), 1);
/* Enable GPT Output Compare1 interrupt */
GPT_EnableInterrupts(vPortGetGptBase(), kGPT_OutputCompare1InterruptEnable);
NVIC_SetPriority(vPortGetGptIrqn(), configMAX_SYSCALL_INTERRUPT_PRIORITY + 2);
ulTimerCountsForOneTick = (configSYSTICK_CLOCK_HZ / configTICK_RATE_HZ);
ulLPTimerCountsForOneTick = configGPT_CLOCK_HZ / configTICK_RATE_HZ;
xMaximumPossibleSuppressedTicks = portMAX_32_BIT_NUMBER / ulLPTimerCountsForOneTick;
NVIC_EnableIRQ(vPortGetGptIrqn());
GPC_EnableIRQ(GPC, vPortGetGptIrqn());
#endif /* configUSE_TICKLESS_IDLE */
/* Configure SysTick to interrupt at the requested rate. */
portNVIC_SYSTICK_LOAD_REG = (configSYSTICK_CLOCK_HZ / configTICK_RATE_HZ) - 1UL;
portNVIC_SYSTICK_CURRENT_VALUE_REG = 0UL;
portNVIC_SYSTICK_CTRL_REG = (portNVIC_SYSTICK_CLK_BIT | portNVIC_SYSTICK_INT_BIT | portNVIC_SYSTICK_ENABLE_BIT);
}
void vPortStopTimerInterrupt(void)
{
#if configUSE_TICKLESS_IDLE == 2
NVIC_DisableIRQ(vPortGetGptIrqn());
NVIC_ClearPendingIRQ(vPortGetGptIrqn());
GPC_DisableIRQ(GPC, vPortGetGptIrqn());
GPT_Deinit(vPortGetGptBase());
#endif
portNVIC_SYSTICK_CTRL_REG = 0;
NVIC_DisableIRQ(SysTick_IRQn);
NVIC_ClearPendingIRQ(SysTick_IRQn);
}