Diff: Source/portable/RVDS/ARM_CM3/port.c

Revision:

1:fc62ab66aa39

Parent:

0:8e57f3e9cc89

--- a/Source/portable/RVDS/ARM_CM3/port.c	Fri Jan 24 14:56:04 2014 +0000
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,696 +0,0 @@
-/*
-    FreeRTOS V7.6.0 - Copyright (C) 2013 Real Time Engineers Ltd. 
-    All rights reserved
-
-    VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.
-
-    ***************************************************************************
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-     *    manual, or both from: http://www.FreeRTOS.org/Documentation        *
-     *                                                                       *
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-     *                                                                       *
-    ***************************************************************************
-
-    This file is part of the FreeRTOS distribution.
-
-    FreeRTOS is free software; you can redistribute it and/or modify it under
-    the terms of the GNU General Public License (version 2) as published by the
-    Free Software Foundation >>!AND MODIFIED BY!<< the FreeRTOS exception.
-
-    >>! NOTE: The modification to the GPL is included to allow you to distribute
-    >>! a combined work that includes FreeRTOS without being obliged to provide
-    >>! the source code for proprietary components outside of the FreeRTOS
-    >>! kernel.
-
-    FreeRTOS is distributed in the hope that it will be useful, but WITHOUT ANY
-    WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
-    FOR A PARTICULAR PURPOSE.  Full license text is available from the following
-    link: http://www.freertos.org/a00114.html
-
-    1 tab == 4 spaces!
-
-    ***************************************************************************
-     *                                                                       *
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-     *    not run, what could be wrong?"                                     *
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-
-    http://www.FreeRTOS.org - Documentation, books, training, latest versions,
-    license and Real Time Engineers Ltd. contact details.
-
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-    compatible FAT file system, and our tiny thread aware UDP/IP stack.
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-    engineered and independently SIL3 certified version for use in safety and
-    mission critical applications that require provable dependability.
-
-    1 tab == 4 spaces!
-*/
-
-/*-----------------------------------------------------------
- * Implementation of functions defined in portable.h for the ARM CM3 port.
- *----------------------------------------------------------*/
-
-/* Scheduler includes. */
-#include "FreeRTOS.h"
-#include "task.h"
-
-#ifndef configKERNEL_INTERRUPT_PRIORITY
-	#define configKERNEL_INTERRUPT_PRIORITY 255
-#endif
-
-#if configMAX_SYSCALL_INTERRUPT_PRIORITY == 0
-	#error configMAX_SYSCALL_INTERRUPT_PRIORITY must not be set to 0.  See http://www.FreeRTOS.org/RTOS-Cortex-M3-M4.html
-#endif
-
-#ifndef configSYSTICK_CLOCK_HZ
-	#define configSYSTICK_CLOCK_HZ configCPU_CLOCK_HZ
-#endif
-
-/* The __weak attribute does not work as you might expect with the Keil tools
-so the configOVERRIDE_DEFAULT_TICK_CONFIGURATION constant must be set to 1 if
-the application writer wants to provide their own implementation of
-vPortSetupTimerInterrupt().  Ensure configOVERRIDE_DEFAULT_TICK_CONFIGURATION
-is defined. */
-#ifndef configOVERRIDE_DEFAULT_TICK_CONFIGURATION
-	#define configOVERRIDE_DEFAULT_TICK_CONFIGURATION 0
-#endif
-
-/* Constants required to manipulate the core.  Registers first... */
-#define portNVIC_SYSTICK_CTRL_REG			( * ( ( volatile unsigned long * ) 0xe000e010 ) )
-#define portNVIC_SYSTICK_LOAD_REG			( * ( ( volatile unsigned long * ) 0xe000e014 ) )
-#define portNVIC_SYSTICK_CURRENT_VALUE_REG	( * ( ( volatile unsigned long * ) 0xe000e018 ) )
-#define portNVIC_SYSPRI2_REG				( * ( ( volatile unsigned long * ) 0xe000ed20 ) )
-/* ...then bits in the registers. */
-#define portNVIC_SYSTICK_CLK_BIT			( 1UL << 2UL )
-#define portNVIC_SYSTICK_INT_BIT			( 1UL << 1UL )
-#define portNVIC_SYSTICK_ENABLE_BIT			( 1UL << 0UL )
-#define portNVIC_SYSTICK_COUNT_FLAG_BIT		( 1UL << 16UL )
-#define portNVIC_PENDSVCLEAR_BIT 			( 1UL << 27UL )
-#define portNVIC_PEND_SYSTICK_CLEAR_BIT		( 1UL << 25UL )
-
-#define portNVIC_PENDSV_PRI					( ( ( unsigned long ) configKERNEL_INTERRUPT_PRIORITY ) << 16UL )
-#define portNVIC_SYSTICK_PRI				( ( ( unsigned long ) configKERNEL_INTERRUPT_PRIORITY ) << 24UL )
-
-/* Constants required to check the validity of an interrupt priority. */
-#define portFIRST_USER_INTERRUPT_NUMBER		( 16 )
-#define portNVIC_IP_REGISTERS_OFFSET_16 	( 0xE000E3F0 )
-#define portAIRCR_REG						( * ( ( volatile unsigned long * ) 0xE000ED0C ) )
-#define portMAX_8_BIT_VALUE					( ( unsigned char ) 0xff )
-#define portTOP_BIT_OF_BYTE					( ( unsigned char ) 0x80 )
-#define portMAX_PRIGROUP_BITS				( ( unsigned char ) 7 )
-#define portPRIORITY_GROUP_MASK				( 0x07UL << 8UL )
-#define portPRIGROUP_SHIFT					( 8UL )
-
-/* Constants required to set up the initial stack. */
-#define portINITIAL_XPSR			( 0x01000000 )
-
-/* Constants used with memory barrier intrinsics. */
-#define portSY_FULL_READ_WRITE		( 15 )
-
-/* The systick is a 24-bit counter. */
-#define portMAX_24_BIT_NUMBER				( 0xffffffUL )
-
-/* A fiddle factor to estimate the number of SysTick counts that would have
-occurred while the SysTick counter is stopped during tickless idle
-calculations. */
-#define portMISSED_COUNTS_FACTOR			( 45UL )
-
-/* Each task maintains its own interrupt status in the critical nesting
-variable. */
-static unsigned portBASE_TYPE uxCriticalNesting = 0xaaaaaaaa;
-
-/*
- * 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.
- */
-void vPortSetupTimerInterrupt( void );
-
-/*
- * Exception handlers.
- */
-void xPortPendSVHandler( void );
-void xPortSysTickHandler( void );
-void vPortSVCHandler( void );
-
-/*
- * Start first task is a separate function so it can be tested in isolation.
- */
-static void prvStartFirstTask( void );
-
-/*
- * Used to catch tasks that attempt to return from their implementing function.
- */
-static void prvTaskExitError( void );
-
-/*-----------------------------------------------------------*/
-
-/*
- * The number of SysTick increments that make up one tick period.
- */
-#if configUSE_TICKLESS_IDLE == 1
-	static unsigned long 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 == 1
-	static unsigned long xMaximumPossibleSuppressedTicks = 0;
-#endif /* configUSE_TICKLESS_IDLE */
-
-/*
- * Compensate for the CPU cycles that pass while the SysTick is stopped (low
- * power functionality only.
- */
-#if configUSE_TICKLESS_IDLE == 1
-	static unsigned long ulStoppedTimerCompensation = 0;
-#endif /* configUSE_TICKLESS_IDLE */
-
-/*
- * Used by the portASSERT_IF_INTERRUPT_PRIORITY_INVALID() macro to ensure 
- * FreeRTOS API functions are not called from interrupts that have been assigned
- * a priority above configMAX_SYSCALL_INTERRUPT_PRIORITY.
- */
-#if ( configASSERT_DEFINED == 1 )
-	 static unsigned char ucMaxSysCallPriority = 0;
-	 static unsigned long ulMaxPRIGROUPValue = 0;
-	 static const volatile unsigned char * const pcInterruptPriorityRegisters = ( unsigned char * ) portNVIC_IP_REGISTERS_OFFSET_16;
-#endif /* configASSERT_DEFINED */
-
-/*-----------------------------------------------------------*/
-
-/*
- * See header file for description.
- */
-portSTACK_TYPE *pxPortInitialiseStack( portSTACK_TYPE *pxTopOfStack, pdTASK_CODE pxCode, void *pvParameters )
-{
-	/* Simulate the stack frame as it would be created by a context switch
-	interrupt. */
-	pxTopOfStack--; /* Offset added to account for the way the MCU uses the stack on entry/exit of interrupts. */
-	*pxTopOfStack = portINITIAL_XPSR;	/* xPSR */
-	pxTopOfStack--;
-	*pxTopOfStack = ( portSTACK_TYPE ) pxCode;	/* PC */
-	pxTopOfStack--;
-	*pxTopOfStack = ( portSTACK_TYPE ) prvTaskExitError;	/* LR */
-
-	pxTopOfStack -= 5;	/* R12, R3, R2 and R1. */
-	*pxTopOfStack = ( portSTACK_TYPE ) pvParameters;	/* R0 */
-	pxTopOfStack -= 8;	/* R11, R10, R9, R8, R7, R6, R5 and R4. */
-
-	return pxTopOfStack;
-}
-/*-----------------------------------------------------------*/
-
-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( ;; );
-}
-/*-----------------------------------------------------------*/
-
-__asm void vPortSVCHandler( void )
-{
-	PRESERVE8
-
-	ldr	r3, =pxCurrentTCB	/* Restore the context. */
-	ldr r1, [r3]			/* Use pxCurrentTCBConst to get the pxCurrentTCB address. */
-	ldr r0, [r1]			/* The first item in pxCurrentTCB is the task top of stack. */
-	ldmia r0!, {r4-r11}		/* Pop the registers that are not automatically saved on exception entry and the critical nesting count. */
-	msr psp, r0				/* Restore the task stack pointer. */
-	mov r0, #0
-	msr	basepri, r0
-	orr r14, #0xd
-	bx r14
-}
-/*-----------------------------------------------------------*/
-
-__asm void prvStartFirstTask( void )
-{
-	PRESERVE8
-
-	/* Use the NVIC offset register to locate the stack. */
-	ldr r0, =0xE000ED08
-	ldr r0, [r0]
-	ldr r0, [r0]
-	/* Set the msp back to the start of the stack. */
-	msr msp, r0
-	/* Globally enable interrupts. */
-	cpsie i
-	/* Call SVC to start the first task. */
-	svc 0
-	nop
-}
-/*-----------------------------------------------------------*/
-
-/*
- * See header file for description.
- */
-portBASE_TYPE xPortStartScheduler( void )
-{
-	#if( configASSERT_DEFINED == 1 )
-	{
-		volatile unsigned long ulOriginalPriority;
-		volatile char * const pcFirstUserPriorityRegister = ( char * ) ( portNVIC_IP_REGISTERS_OFFSET_16 + portFIRST_USER_INTERRUPT_NUMBER );
-		volatile unsigned char ucMaxPriorityValue;
-
-		/* Determine the maximum priority from which ISR safe FreeRTOS API
-		functions can be called.  ISR safe functions are those that end in
-		"FromISR".  FreeRTOS maintains separate thread and ISR API functions to
-		ensure interrupt entry is as fast and simple as possible.
-
-		Save the interrupt priority value that is about to be clobbered. */
-		ulOriginalPriority = *pcFirstUserPriorityRegister;
-
-		/* Determine the number of priority bits available.  First write to all
-		possible bits. */
-		*pcFirstUserPriorityRegister = portMAX_8_BIT_VALUE;
-
-		/* Read the value back to see how many bits stuck. */
-		ucMaxPriorityValue = *pcFirstUserPriorityRegister;
-
-		/* Use the same mask on the maximum system call priority. */
-		ucMaxSysCallPriority = configMAX_SYSCALL_INTERRUPT_PRIORITY & ucMaxPriorityValue;
-
-		/* Calculate the maximum acceptable priority group value for the number
-		of bits read back. */
-		ulMaxPRIGROUPValue = portMAX_PRIGROUP_BITS;
-		while( ( ucMaxPriorityValue & portTOP_BIT_OF_BYTE ) == portTOP_BIT_OF_BYTE )
-		{
-			ulMaxPRIGROUPValue--;
-			ucMaxPriorityValue <<= ( unsigned char ) 0x01;
-		}
-
-		/* Shift the priority group value back to its position within the AIRCR
-		register. */
-		ulMaxPRIGROUPValue <<= portPRIGROUP_SHIFT;
-		ulMaxPRIGROUPValue &= portPRIORITY_GROUP_MASK;
-
-		/* Restore the clobbered interrupt priority register to its original
-		value. */
-		*pcFirstUserPriorityRegister = ulOriginalPriority;
-	}
-	#endif /* conifgASSERT_DEFINED */
-
-	/* Make PendSV and SysTick the lowest priority interrupts. */
-	portNVIC_SYSPRI2_REG |= portNVIC_PENDSV_PRI;
-	portNVIC_SYSPRI2_REG |= portNVIC_SYSTICK_PRI;
-
-	/* Start the timer that generates the tick ISR.  Interrupts are disabled
-	here already. */
-	vPortSetupTimerInterrupt();
-
-	/* Initialise the critical nesting count ready for the first task. */
-	uxCriticalNesting = 0;
-
-	/* Start the first task. */
-	prvStartFirstTask();
-
-	/* Should not get here! */
-	return 0;
-}
-/*-----------------------------------------------------------*/
-
-void vPortEndScheduler( void )
-{
-	/* It is unlikely that the CM3 port will require this function as there
-	is nothing to return to.  */
-}
-/*-----------------------------------------------------------*/
-
-void vPortYield( void )
-{
-	/* Set a PendSV to request a context switch. */
-	portNVIC_INT_CTRL_REG = portNVIC_PENDSVSET_BIT;
-
-	/* Barriers are normally not required but do ensure the code is completely
-	within the specified behaviour for the architecture. */
-	__dsb( portSY_FULL_READ_WRITE );
-	__isb( portSY_FULL_READ_WRITE );
-}
-/*-----------------------------------------------------------*/
-
-void vPortEnterCritical( void )
-{
-	portDISABLE_INTERRUPTS();
-	uxCriticalNesting++;
-	__dsb( portSY_FULL_READ_WRITE );
-	__isb( portSY_FULL_READ_WRITE );
-}
-/*-----------------------------------------------------------*/
-
-void vPortExitCritical( void )
-{
-	uxCriticalNesting--;
-	if( uxCriticalNesting == 0 )
-	{
-		portENABLE_INTERRUPTS();
-	}
-}
-/*-----------------------------------------------------------*/
-
-__asm void xPortPendSVHandler( void )
-{
-	extern uxCriticalNesting;
-	extern pxCurrentTCB;
-	extern vTaskSwitchContext;
-
-	PRESERVE8
-
-	mrs r0, psp
-
-	ldr	r3, =pxCurrentTCB		/* Get the location of the current TCB. */
-	ldr	r2, [r3]
-
-	stmdb r0!, {r4-r11}			/* Save the remaining registers. */
-	str r0, [r2]				/* Save the new top of stack into the first member of the TCB. */
-
-	stmdb sp!, {r3, r14}
-	mov r0, #configMAX_SYSCALL_INTERRUPT_PRIORITY
-	msr basepri, r0
-	bl vTaskSwitchContext
-	mov r0, #0
-	msr basepri, r0
-	ldmia sp!, {r3, r14}
-
-	ldr r1, [r3]
-	ldr r0, [r1]				/* The first item in pxCurrentTCB is the task top of stack. */
-	ldmia r0!, {r4-r11}			/* Pop the registers and the critical nesting count. */
-	msr psp, r0
-	bx r14
-	nop
-}
-/*-----------------------------------------------------------*/
-
-void xPortSysTickHandler( void )
-{
-	/* The SysTick runs at the lowest interrupt priority, so when this interrupt
-	executes all interrupts must be unmasked.  There is therefore no need to
-	save and then restore the interrupt mask value as its value is already
-	known. */
-	( void ) portSET_INTERRUPT_MASK_FROM_ISR();
-	{
-		/* Increment the RTOS tick. */
-		if( xTaskIncrementTick() != pdFALSE )
-		{
-			/* A context switch is required.  Context switching is performed in
-			the PendSV interrupt.  Pend the PendSV interrupt. */
-			portNVIC_INT_CTRL_REG = portNVIC_PENDSVSET_BIT;
-		}
-	}
-	portCLEAR_INTERRUPT_MASK_FROM_ISR( 0 );
-}
-/*-----------------------------------------------------------*/
-
-#if configUSE_TICKLESS_IDLE == 1
-
-	__weak void vPortSuppressTicksAndSleep( portTickType xExpectedIdleTime )
-	{
-	unsigned long ulReloadValue, ulCompleteTickPeriods, ulCompletedSysTickDecrements;
-	portTickType xModifiableIdleTime;
-
-		/* Make sure the SysTick reload value does not overflow the counter. */
-		if( xExpectedIdleTime > xMaximumPossibleSuppressedTicks )
-		{
-			xExpectedIdleTime = xMaximumPossibleSuppressedTicks;
-		}
-
-		/* Stop the SysTick momentarily.  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;
-
-		/* 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 = portNVIC_SYSTICK_CURRENT_VALUE_REG + ( ulTimerCountsForOneTick * ( xExpectedIdleTime - 1UL ) );
-		if( ulReloadValue > ulStoppedTimerCompensation )
-		{
-			ulReloadValue -= ulStoppedTimerCompensation;
-		}
-
-		/* Enter a critical section but don't use the taskENTER_CRITICAL()
-		method as that will mask interrupts that should exit sleep mode. */
-		__disable_irq();
-
-		/* 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_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 __disable_irq() call
-			above. */
-			__enable_irq();
-		}
-		else
-		{
-			/* Set the new reload value. */
-			portNVIC_SYSTICK_LOAD_REG = ulReloadValue;
-
-			/* Clear the SysTick count flag and set the count value back to
-			zero. */
-			portNVIC_SYSTICK_CURRENT_VALUE_REG = 0UL;
-
-			/* Restart SysTick. */
-			portNVIC_SYSTICK_CTRL_REG = portNVIC_SYSTICK_CLK_BIT | portNVIC_SYSTICK_INT_BIT | portNVIC_SYSTICK_ENABLE_BIT;
-
-			/* 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( portSY_FULL_READ_WRITE );
-				__wfi();
-				__isb( portSY_FULL_READ_WRITE );
-			}
-			configPOST_SLEEP_PROCESSING( xExpectedIdleTime );
-
-			/* Stop SysTick.  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;
-
-			/* Re-enable interrupts - see comments above __disable_irq() call
-			above. */
-			__enable_irq();
-
-			if( ( portNVIC_SYSTICK_CTRL_REG & portNVIC_SYSTICK_COUNT_FLAG_BIT ) != 0 )
-			{
-				unsigned long ulCalculatedLoadValue;
-				
-				/* The tick interrupt has already executed, and the SysTick
-				count reloaded with ulReloadValue.  Reset the
-				portNVIC_SYSTICK_LOAD_REG with whatever remains of this tick
-				period. */
-				ulCalculatedLoadValue = ( ulTimerCountsForOneTick - 1UL ) - ( ulReloadValue - portNVIC_SYSTICK_CURRENT_VALUE_REG );
-
-				/* Don't allow a tiny value, or values that have somehow 
-				underflowed because the post sleep hook did something 
-				that took too long. */
-				if( ( ulCalculatedLoadValue < ulStoppedTimerCompensation ) || ( ulCalculatedLoadValue > ulTimerCountsForOneTick ) )
-				{
-					ulCalculatedLoadValue = ( ulTimerCountsForOneTick - 1UL );
-				}
-				
-				portNVIC_SYSTICK_LOAD_REG = ulCalculatedLoadValue;
-				
-				/* 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;
-			}
-			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). */
-				ulCompletedSysTickDecrements = ( xExpectedIdleTime * ulTimerCountsForOneTick ) - portNVIC_SYSTICK_CURRENT_VALUE_REG;
-
-				/* How many complete tick periods passed while the processor
-				was waiting? */
-				ulCompleteTickPeriods = ulCompletedSysTickDecrements / ulTimerCountsForOneTick;
-
-				/* The reload value is set to whatever fraction of a single tick
-				period remains. */
-				portNVIC_SYSTICK_LOAD_REG = ( ( ulCompleteTickPeriods + 1 ) * ulTimerCountsForOneTick ) - ulCompletedSysTickDecrements;
-			}
-
-			/* Restart SysTick so it runs from portNVIC_SYSTICK_LOAD_REG
-			again, 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. */
-			portNVIC_SYSTICK_CURRENT_VALUE_REG = 0UL;
-			portENTER_CRITICAL();
-			{
-				portNVIC_SYSTICK_CTRL_REG = portNVIC_SYSTICK_CLK_BIT | portNVIC_SYSTICK_INT_BIT | 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.
- */
-#if configOVERRIDE_DEFAULT_TICK_CONFIGURATION == 0
-
-	void vPortSetupTimerInterrupt( void )
-	{
-		/* Calculate the constants required to configure the tick interrupt. */
-		#if configUSE_TICKLESS_IDLE == 1
-		{
-			ulTimerCountsForOneTick = ( configSYSTICK_CLOCK_HZ / configTICK_RATE_HZ );
-			xMaximumPossibleSuppressedTicks = portMAX_24_BIT_NUMBER / ulTimerCountsForOneTick;
-			ulStoppedTimerCompensation = portMISSED_COUNTS_FACTOR / ( configCPU_CLOCK_HZ / configSYSTICK_CLOCK_HZ );
-		}
-		#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_CTRL_REG = portNVIC_SYSTICK_CLK_BIT | portNVIC_SYSTICK_INT_BIT | portNVIC_SYSTICK_ENABLE_BIT;
-	}
-
-#endif /* configOVERRIDE_DEFAULT_TICK_CONFIGURATION */
-/*-----------------------------------------------------------*/
-
-__asm unsigned long ulPortSetInterruptMask( void )
-{
-	PRESERVE8
-
-	mrs r0, basepri
-	mov r1, #configMAX_SYSCALL_INTERRUPT_PRIORITY
-	msr basepri, r1
-	bx r14
-}
-/*-----------------------------------------------------------*/
-
-__asm void vPortClearInterruptMask( unsigned long ulNewMask )
-{
-	PRESERVE8
-
-	msr basepri, r0
-	bx r14
-}
-/*-----------------------------------------------------------*/
-
-__asm unsigned long vPortGetIPSR( void )
-{
-	PRESERVE8
-	
-	mrs r0, ipsr
-	bx r14
-}
-/*-----------------------------------------------------------*/
-
-#if( configASSERT_DEFINED == 1 )
-
-	void vPortValidateInterruptPriority( void )
-	{
-	unsigned long ulCurrentInterrupt;
-	unsigned char ucCurrentPriority;
-
-		/* Obtain the number of the currently executing interrupt. */
-		ulCurrentInterrupt = vPortGetIPSR();
-
-		/* Is the interrupt number a user defined interrupt? */
-		if( ulCurrentInterrupt >= portFIRST_USER_INTERRUPT_NUMBER )
-		{
-			/* Look up the interrupt's priority. */
-			ucCurrentPriority = pcInterruptPriorityRegisters[ ulCurrentInterrupt ];
-
-			/* The following assertion will fail if a service routine (ISR) for
-			an interrupt that has been assigned a priority above
-			configMAX_SYSCALL_INTERRUPT_PRIORITY calls an ISR safe FreeRTOS API
-			function.  ISR safe FreeRTOS API functions must *only* be called
-			from interrupts that have been assigned a priority at or below
-			configMAX_SYSCALL_INTERRUPT_PRIORITY.
-
-			Numerically low interrupt priority numbers represent logically high
-			interrupt priorities, therefore the priority of the interrupt must
-			be set to a value equal to or numerically *higher* than
-			configMAX_SYSCALL_INTERRUPT_PRIORITY.
-
-			Interrupts that	use the FreeRTOS API must not be left at their
-			default priority of	zero as that is the highest possible priority,
-			which is guaranteed to be above configMAX_SYSCALL_INTERRUPT_PRIORITY,
-			and	therefore also guaranteed to be invalid.
-
-			FreeRTOS maintains separate thread and ISR API functions to ensure
-			interrupt entry is as fast and simple as possible.
-
-			The following links provide detailed information:
-			http://www.freertos.org/RTOS-Cortex-M3-M4.html
-			http://www.freertos.org/FAQHelp.html */
-			configASSERT( ucCurrentPriority >= ucMaxSysCallPriority );
-		}
-
-		/* Priority grouping:  The interrupt controller (NVIC) allows the bits
-		that define each interrupt's priority to be split between bits that
-		define the interrupt's pre-emption priority bits and bits that define
-		the interrupt's sub-priority.  For simplicity all bits must be defined
-		to be pre-emption priority bits.  The following assertion will fail if
-		this is not the case (if some bits represent a sub-priority).
-
-		If the application only uses CMSIS libraries for interrupt
-		configuration then the correct setting can be achieved on all Cortex-M
-		devices by calling NVIC_SetPriorityGrouping( 0 ); before starting the
-		scheduler.  Note however that some vendor specific peripheral libraries
-		assume a non-zero priority group setting, in which cases using a value
-		of zero will result in unpredicable behaviour. */
-		configASSERT( ( portAIRCR_REG & portPRIORITY_GROUP_MASK ) <= ulMaxPRIGROUPValue );
-	}
-
-#endif /* configASSERT_DEFINED */
-
-