Introduce the prvTaskExitError() function for all ARM_CMn ports.

Introduce the configTASK_RETURN_ADDRESS macro for the GCC ARM_CMn ports.
Improve time slippage penalty when entering tickless mode is abandoned.
This commit is contained in:
Richard Barry 2013-10-08 11:30:40 +00:00
parent 81e141ad86
commit aedf7824cb
7 changed files with 217 additions and 29 deletions

View file

@ -118,6 +118,15 @@ occurred while the SysTick counter is stopped during tickless idle
calculations. */
#define portMISSED_COUNTS_FACTOR ( 45UL )
/* Let the user override the pre-loading of the initial LR with the address of
prvTaskExitError() in case is messes up unwinding of the stack in the
debugger. */
#ifdef configTASK_RETURN_ADDRESS
#define portTASK_RETURN_ADDRESS configTASK_RETURN_ADDRESS
#else
#define portTASK_RETURN_ADDRESS prvTaskExitError
#endif
/* Each task maintains its own interrupt status in the critical nesting
variable. */
static unsigned portBASE_TYPE uxCriticalNesting = 0xaaaaaaaa;
@ -141,6 +150,11 @@ void vPortSVCHandler( void ) __attribute__ (( naked ));
*/
static void prvPortStartFirstTask( void ) __attribute__ (( naked ));
/*
* Used to catch tasks that attempt to return from their implementing function.
*/
static void prvTaskExitError( void );
/*-----------------------------------------------------------*/
/*
@ -191,7 +205,7 @@ portSTACK_TYPE *pxPortInitialiseStack( portSTACK_TYPE *pxTopOfStack, pdTASK_CODE
pxTopOfStack--;
*pxTopOfStack = ( portSTACK_TYPE ) pxCode; /* PC */
pxTopOfStack--;
*pxTopOfStack = 0; /* LR */
*pxTopOfStack = ( portSTACK_TYPE ) portTASK_RETURN_ADDRESS; /* LR */
pxTopOfStack -= 5; /* R12, R3, R2 and R1. */
*pxTopOfStack = ( portSTACK_TYPE ) pvParameters; /* R0 */
pxTopOfStack -= 8; /* R11, R10, R9, R8, R7, R6, R5 and R4. */
@ -200,6 +214,20 @@ portSTACK_TYPE *pxPortInitialiseStack( portSTACK_TYPE *pxTopOfStack, pdTASK_CODE
}
/*-----------------------------------------------------------*/
static void prvTaskExitError( void )
{
/* A function that implements a task must not exit or attempt to return to
its caller as there is nothing to return to. If a task wants to exit it
should instead call vTaskDelete( NULL ).
Artificially force an assert() to be triggered if configASSERT() is
defined, then stop here so application writers can catch the error. */
configASSERT( uxCriticalNesting == ~0UL );
portDISABLE_INTERRUPTS();
for( ;; );
}
/*-----------------------------------------------------------*/
void vPortSVCHandler( void )
{
__asm volatile (
@ -465,8 +493,16 @@ void xPortSysTickHandler( void )
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_CLK_BIT | portNVIC_SYSTICK_INT_BIT | 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 the cpsid instruction()
above. */