len0rd/FreeRTOS-Kernel
1
0
Fork 0
mirror of https://github.com/FreeRTOS/FreeRTOS-Kernel.git synced 2025-09-01 11:53:53 -04:00
Code Issues Projects Releases Packages Wiki Activity

Replace the static prvSetupTimerInterrupt() function in the Cortex-M port layers that still used it (other than MPU ports so far) with a weakly defined function call vPortSetupTimerInterrupt() - which allows application writers to override the function with one that uses a different clock.

Browse source
This commit is contained in:
Richard Barry 2019-12-30 21:16:09 +00:00
parent e23d638afd
commit e292c67933
6 changed files with 68 additions and 49 deletions
Download patch file Download diff file Expand all files Collapse all files

22
FreeRTOS/Source/portable/IAR/ARM_CM0/port.c
View file

@ -92,9 +92,11 @@ power functionality only. */
#endif /* configUSE_TICKLESS_IDLE */
/*
* Setup the timer to generate the tick interrupts.
* Setup the timer to generate the tick interrupts. The implementation in this
* file is weak to allow application writers to change the timer used to
* generate the tick interrupt.
*/
static void prvSetupTimerInterrupt( void );
void vPortSetupTimerInterrupt( void );
/*
* Exception handlers.
@ -159,7 +161,7 @@ BaseType_t xPortStartScheduler( void )
/* Start the timer that generates the tick ISR. Interrupts are disabled
here already. */
prvSetupTimerInterrupt();
vPortSetupTimerInterrupt();
/* Initialise the critical nesting count ready for the first task. */
uxCriticalNesting = 0;
@ -233,7 +235,7 @@ uint32_t ulPreviousMask;
* Setup the systick timer to generate the tick interrupts at the required
* frequency.
*/
static void prvSetupTimerInterrupt( void )
__weak void vPortSetupTimerInterrupt( void )
{
/* Calculate the constants required to configure the tick interrupt. */
#if( configUSE_TICKLESS_IDLE == 1 )
@ -243,7 +245,7 @@ static void prvSetupTimerInterrupt( void )
ulStoppedTimerCompensation = portMISSED_COUNTS_FACTOR;
}
#endif /* configUSE_TICKLESS_IDLE */
/* Stop and reset the SysTick. */
portNVIC_SYSTICK_CTRL_REG = 0UL;
portNVIC_SYSTICK_CURRENT_VALUE_REG = 0UL;
@ -349,12 +351,12 @@ TickType_t xModifiableIdleTime;
__DSB();
__ISB();
/* Disable the SysTick clock without reading the
/* Disable the SysTick clock without reading the
portNVIC_SYSTICK_CTRL_REG register to ensure the
portNVIC_SYSTICK_COUNT_FLAG_BIT is not cleared if it is set. Again,
the time the 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
portNVIC_SYSTICK_COUNT_FLAG_BIT is not cleared if it is set. Again,
the time the 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*/
portNVIC_SYSTICK_CTRL_REG = ( portNVIC_SYSTICK_CLK_BIT | portNVIC_SYSTICK_INT_BIT );