/*\r
- FreeRTOS V7.5.1 - Copyright (C) 2013 Real Time Engineers Ltd.\r
+ FreeRTOS V7.6.0 - Copyright (C) 2013 Real Time Engineers Ltd.\r
+ All rights reserved\r
\r
VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.\r
\r
calculations. */\r
#define portMISSED_COUNTS_FACTOR ( 45UL )\r
\r
+/* Let the user override the pre-loading of the initial LR with the address of\r
+prvTaskExitError() in case is messes up unwinding of the stack in the\r
+debugger. */\r
+#ifdef configTASK_RETURN_ADDRESS\r
+ #define portTASK_RETURN_ADDRESS configTASK_RETURN_ADDRESS\r
+#else\r
+ #define portTASK_RETURN_ADDRESS prvTaskExitError\r
+#endif\r
+\r
/* Each task maintains its own interrupt status in the critical nesting\r
variable. */\r
static unsigned portBASE_TYPE uxCriticalNesting = 0xaaaaaaaa;\r
*/\r
static void vPortEnableVFP( void ) __attribute__ (( naked ));\r
\r
+/*\r
+ * Used to catch tasks that attempt to return from their implementing function.\r
+ */\r
+static void prvTaskExitError( void );\r
+\r
/*-----------------------------------------------------------*/\r
\r
/*\r
#endif /* configUSE_TICKLESS_IDLE */\r
\r
/*\r
- * Used by the portASSERT_IF_INTERRUPT_PRIORITY_INVALID() macro to ensure \r
+ * Used by the portASSERT_IF_INTERRUPT_PRIORITY_INVALID() macro to ensure\r
* FreeRTOS API functions are not called from interrupts that have been assigned\r
* a priority above configMAX_SYSCALL_INTERRUPT_PRIORITY.\r
*/\r
pxTopOfStack--;\r
*pxTopOfStack = ( portSTACK_TYPE ) pxCode; /* PC */\r
pxTopOfStack--;\r
- *pxTopOfStack = 0; /* LR */\r
+ *pxTopOfStack = ( portSTACK_TYPE ) portTASK_RETURN_ADDRESS; /* LR */\r
\r
/* Save code space by skipping register initialisation. */\r
pxTopOfStack -= 5; /* R12, R3, R2 and R1. */\r
}\r
/*-----------------------------------------------------------*/\r
\r
+static void prvTaskExitError( void )\r
+{\r
+ /* A function that implements a task must not exit or attempt to return to\r
+ its caller as there is nothing to return to. If a task wants to exit it\r
+ should instead call vTaskDelete( NULL ).\r
+\r
+ Artificially force an assert() to be triggered if configASSERT() is\r
+ defined, then stop here so application writers can catch the error. */\r
+ configASSERT( uxCriticalNesting == ~0UL );\r
+ portDISABLE_INTERRUPTS();\r
+ for( ;; );\r
+}\r
+/*-----------------------------------------------------------*/\r
+\r
void vPortSVCHandler( void )\r
{\r
__asm volatile (\r
/* Start the first task. */\r
prvPortStartFirstTask();\r
\r
+ /* Should never get here as the tasks will now be executing! Call the task\r
+ exit error function to prevent compiler warnings about a static function\r
+ not being called in the case that the application writer overrides this\r
+ functionality by defining configTASK_RETURN_ADDRESS. */\r
+ prvTaskExitError();\r
+\r
/* Should not get here! */\r
return 0;\r
}\r
(\r
" mrs r0, psp \n"\r
" \n"\r
- " ldr r3, pxCurrentTCBConst \n" /* Get the location of the current TCB. */\r
+ " ldr r3, pxCurrentTCBConst \n" /* Get the location of the current TCB. */\r
" ldr r2, [r3] \n"\r
" \n"\r
" tst r14, #0x10 \n" /* Is the task using the FPU context? If so, push high vfp registers. */\r
" \n"\r
" str r0, [r2] \n" /* Save the new top of stack into the first member of the TCB. */\r
" \n"\r
- " stmdb sp!, {r3, r14} \n"\r
+ " stmdb sp!, {r3} \n"\r
" mov r0, %0 \n"\r
" msr basepri, r0 \n"\r
" bl vTaskSwitchContext \n"\r
" mov r0, #0 \n"\r
" msr basepri, r0 \n"\r
- " ldmia sp!, {r3, r14} \n"\r
+ " ldmia sp!, {r3} \n"\r
" \n"\r
" ldr r1, [r3] \n" /* The first item in pxCurrentTCB is the task top of stack. */\r
" ldr r0, [r1] \n"\r
" vldmiaeq r0!, {s16-s31} \n"\r
" \n"\r
" msr psp, r0 \n"\r
+ " \n"\r
+ #ifdef WORKAROUND_PMU_CM001 /* XMC4000 specific errata workaround. */\r
+ #if WORKAROUND_PMU_CM001 == 1\r
+ " push { r14 } \n"\r
+ " pop { pc } \n"\r
+ #endif\r
+ #endif\r
+ " \n"\r
" bx r14 \n"\r
" \n"\r
" .align 2 \n"\r
to be unsuspended then abandon the low power entry. */\r
if( eTaskConfirmSleepModeStatus() == eAbortSleep )\r
{\r
+ /* Restart from whatever is left in the count register to complete\r
+ this tick period. */\r
+ portNVIC_SYSTICK_LOAD_REG = portNVIC_SYSTICK_CURRENT_VALUE_REG;\r
+\r
/* Restart SysTick. */\r
portNVIC_SYSTICK_CTRL_REG = portNVIC_SYSTICK_CLK_BIT | portNVIC_SYSTICK_INT_BIT | portNVIC_SYSTICK_ENABLE_BIT;\r
\r
+ /* Reset the reload register to the value required for normal tick\r
+ periods. */\r
+ portNVIC_SYSTICK_LOAD_REG = ulTimerCountsForOneTick - 1UL;\r
+\r
/* Re-enable interrupts - see comments above the cpsid instruction()\r
above. */\r
__asm volatile( "cpsie i" );\r
\r
if( ( portNVIC_SYSTICK_CTRL_REG & portNVIC_SYSTICK_COUNT_FLAG_BIT ) != 0 )\r
{\r
+ unsigned long ulCalculatedLoadValue;\r
+\r
/* The tick interrupt has already executed, and the SysTick\r
count reloaded with ulReloadValue. Reset the\r
portNVIC_SYSTICK_LOAD_REG with whatever remains of this tick\r
period. */\r
- portNVIC_SYSTICK_LOAD_REG = ( ulTimerCountsForOneTick - 1UL ) - ( ulReloadValue - portNVIC_SYSTICK_CURRENT_VALUE_REG );\r
+ ulCalculatedLoadValue = ( ulTimerCountsForOneTick - 1UL ) - ( ulReloadValue - portNVIC_SYSTICK_CURRENT_VALUE_REG );\r
+\r
+ /* Don't allow a tiny value, or values that have somehow\r
+ underflowed because the post sleep hook did something\r
+ that took too long. */\r
+ if( ( ulCalculatedLoadValue < ulStoppedTimerCompensation ) || ( ulCalculatedLoadValue > ulTimerCountsForOneTick ) )\r
+ {\r
+ ulCalculatedLoadValue = ( ulTimerCountsForOneTick - 1UL );\r
+ }\r
+\r
+ portNVIC_SYSTICK_LOAD_REG = ulCalculatedLoadValue;\r
\r
/* The tick interrupt handler will already have pended the tick\r
processing in the kernel. As the pending tick will be\r
\r
/* Restart SysTick so it runs from portNVIC_SYSTICK_LOAD_REG\r
again, then set portNVIC_SYSTICK_LOAD_REG back to its standard\r
- value. */\r
+ value. The critical section is used to ensure the tick interrupt\r
+ can only execute once in the case that the reload register is near\r
+ zero. */\r
portNVIC_SYSTICK_CURRENT_VALUE_REG = 0UL;\r
- portNVIC_SYSTICK_CTRL_REG = portNVIC_SYSTICK_CLK_BIT | portNVIC_SYSTICK_INT_BIT | portNVIC_SYSTICK_ENABLE_BIT;\r
-\r
- vTaskStepTick( ulCompleteTickPeriods );\r
-\r
- /* The counter must start by the time the reload value is reset. */\r
- configASSERT( portNVIC_SYSTICK_CURRENT_VALUE_REG );\r
- portNVIC_SYSTICK_LOAD_REG = ulTimerCountsForOneTick - 1UL;\r
+ portENTER_CRITICAL();\r
+ {\r
+ portNVIC_SYSTICK_CTRL_REG = portNVIC_SYSTICK_CLK_BIT | portNVIC_SYSTICK_INT_BIT | portNVIC_SYSTICK_ENABLE_BIT;\r
+ vTaskStepTick( ulCompleteTickPeriods );\r
+ portNVIC_SYSTICK_LOAD_REG = ulTimerCountsForOneTick - 1UL;\r
+ }\r
+ portEXIT_CRITICAL();\r
}\r
}\r
\r
projects / freertos / blobdiff