390 lines
		
	
	
		
			15 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			390 lines
		
	
	
		
			15 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
|   | /*
 | ||
|  |     FreeRTOS V7.3.0 - Copyright (C) 2012 Real Time Engineers Ltd. | ||
|  | 
 | ||
|  |     FEATURES AND PORTS ARE ADDED TO FREERTOS ALL THE TIME.  PLEASE VISIT  | ||
|  |     http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.
 | ||
|  | 
 | ||
|  |     *************************************************************************** | ||
|  |      *                                                                       * | ||
|  |      *    FreeRTOS tutorial books are available in pdf and paperback.        * | ||
|  |      *    Complete, revised, and edited pdf reference manuals are also       * | ||
|  |      *    available.                                                         * | ||
|  |      *                                                                       * | ||
|  |      *    Purchasing FreeRTOS documentation will not only help you, by       * | ||
|  |      *    ensuring you get running as quickly as possible and with an        * | ||
|  |      *    in-depth knowledge of how to use FreeRTOS, it will also help       * | ||
|  |      *    the FreeRTOS project to continue with its mission of providing     * | ||
|  |      *    professional grade, cross platform, de facto standard solutions    * | ||
|  |      *    for microcontrollers - completely free of charge!                  * | ||
|  |      *                                                                       * | ||
|  |      *    >>> See http://www.FreeRTOS.org/Documentation for details. <<<     *
 | ||
|  |      *                                                                       * | ||
|  |      *    Thank you for using FreeRTOS, and thank you for your support!      * | ||
|  |      *                                                                       * | ||
|  |     *************************************************************************** | ||
|  | 
 | ||
|  | 
 | ||
|  |     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.  See the GNU General Public License for | ||
|  |     more details. You should have received a copy of the GNU General Public | ||
|  |     License and the FreeRTOS license exception along with FreeRTOS; if not it | ||
|  |     can be viewed here: http://www.freertos.org/a00114.html and also obtained
 | ||
|  |     by writing to Richard Barry, contact details for whom are available on the | ||
|  |     FreeRTOS WEB site. | ||
|  | 
 | ||
|  |     1 tab == 4 spaces! | ||
|  |      | ||
|  |     *************************************************************************** | ||
|  |      *                                                                       * | ||
|  |      *    Having a problem?  Start by reading the FAQ "My application does   * | ||
|  |      *    not run, what could be wrong?"                                     * | ||
|  |      *                                                                       * | ||
|  |      *    http://www.FreeRTOS.org/FAQHelp.html                               *
 | ||
|  |      *                                                                       * | ||
|  |     *************************************************************************** | ||
|  | 
 | ||
|  |      | ||
|  |     http://www.FreeRTOS.org - Documentation, training, latest versions, license 
 | ||
|  |     and contact details.   | ||
|  |      | ||
|  |     http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
 | ||
|  |     including FreeRTOS+Trace - an indispensable productivity tool. | ||
|  | 
 | ||
|  |     Real Time Engineers ltd license FreeRTOS to High Integrity Systems, who sell  | ||
|  |     the code with commercial support, indemnification, and middleware, under  | ||
|  |     the OpenRTOS brand: http://www.OpenRTOS.com.  High Integrity Systems also
 | ||
|  |     provide a safety engineered and independently SIL3 certified version under  | ||
|  |     the SafeRTOS brand: http://www.SafeRTOS.com.
 | ||
|  | */ | ||
|  | 
 | ||
|  | #include "FreeRTOS.h"
 | ||
|  | #include "task.h"
 | ||
|  | #include "croutine.h"
 | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * Some kernel aware debuggers require data to be viewed to be global, rather | ||
|  |  * than file scope. | ||
|  |  */ | ||
|  | #ifdef portREMOVE_STATIC_QUALIFIER
 | ||
|  | 	#define static
 | ||
|  | #endif
 | ||
|  | 
 | ||
|  | 
 | ||
|  | /* Lists for ready and blocked co-routines. --------------------*/ | ||
|  | static xList pxReadyCoRoutineLists[ configMAX_CO_ROUTINE_PRIORITIES ];	/*< Prioritised ready co-routines. */ | ||
|  | static xList xDelayedCoRoutineList1;									/*< Delayed co-routines. */ | ||
|  | static xList xDelayedCoRoutineList2;									/*< Delayed co-routines (two lists are used - one for delays that have overflowed the current tick count. */ | ||
|  | static xList * pxDelayedCoRoutineList;									/*< Points to the delayed co-routine list currently being used. */ | ||
|  | static xList * pxOverflowDelayedCoRoutineList;							/*< Points to the delayed co-routine list currently being used to hold co-routines that have overflowed the current tick count. */ | ||
|  | static xList xPendingReadyCoRoutineList;											/*< Holds co-routines that have been readied by an external event.  They cannot be added directly to the ready lists as the ready lists cannot be accessed by interrupts. */ | ||
|  | 
 | ||
|  | /* Other file private variables. --------------------------------*/ | ||
|  | corCRCB * pxCurrentCoRoutine = NULL; | ||
|  | static unsigned portBASE_TYPE uxTopCoRoutineReadyPriority = 0; | ||
|  | static portTickType xCoRoutineTickCount = 0, xLastTickCount = 0, xPassedTicks = 0; | ||
|  | 
 | ||
|  | /* The initial state of the co-routine when it is created. */ | ||
|  | #define corINITIAL_STATE	( 0 )
 | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * Place the co-routine represented by pxCRCB into the appropriate ready queue | ||
|  |  * for the priority.  It is inserted at the end of the list. | ||
|  |  * | ||
|  |  * This macro accesses the co-routine ready lists and therefore must not be | ||
|  |  * used from within an ISR. | ||
|  |  */ | ||
|  | #define prvAddCoRoutineToReadyQueue( pxCRCB )																		\
 | ||
|  | {																													\ | ||
|  | 	if( pxCRCB->uxPriority > uxTopCoRoutineReadyPriority )															\ | ||
|  | 	{																												\ | ||
|  | 		uxTopCoRoutineReadyPriority = pxCRCB->uxPriority;															\ | ||
|  | 	}																												\ | ||
|  | 	vListInsertEnd( ( xList * ) &( pxReadyCoRoutineLists[ pxCRCB->uxPriority ] ), &( pxCRCB->xGenericListItem ) );	\ | ||
|  | }	 | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * Utility to ready all the lists used by the scheduler.  This is called | ||
|  |  * automatically upon the creation of the first co-routine. | ||
|  |  */ | ||
|  | static void prvInitialiseCoRoutineLists( void ); | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * Co-routines that are readied by an interrupt cannot be placed directly into | ||
|  |  * the ready lists (there is no mutual exclusion).  Instead they are placed in | ||
|  |  * in the pending ready list in order that they can later be moved to the ready | ||
|  |  * list by the co-routine scheduler. | ||
|  |  */ | ||
|  | static void prvCheckPendingReadyList( void ); | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * Macro that looks at the list of co-routines that are currently delayed to | ||
|  |  * see if any require waking. | ||
|  |  * | ||
|  |  * Co-routines are stored in the queue in the order of their wake time - | ||
|  |  * meaning once one co-routine has been found whose timer has not expired | ||
|  |  * we need not look any further down the list. | ||
|  |  */ | ||
|  | static void prvCheckDelayedList( void ); | ||
|  | 
 | ||
|  | /*-----------------------------------------------------------*/ | ||
|  | 
 | ||
|  | signed portBASE_TYPE xCoRoutineCreate( crCOROUTINE_CODE pxCoRoutineCode, unsigned portBASE_TYPE uxPriority, unsigned portBASE_TYPE uxIndex ) | ||
|  | { | ||
|  | signed portBASE_TYPE xReturn; | ||
|  | corCRCB *pxCoRoutine; | ||
|  | 
 | ||
|  | 	/* Allocate the memory that will store the co-routine control block. */ | ||
|  | 	pxCoRoutine = ( corCRCB * ) pvPortMalloc( sizeof( corCRCB ) ); | ||
|  | 	if( pxCoRoutine ) | ||
|  | 	{ | ||
|  | 		/* If pxCurrentCoRoutine is NULL then this is the first co-routine to
 | ||
|  | 		be created and the co-routine data structures need initialising. */ | ||
|  | 		if( pxCurrentCoRoutine == NULL ) | ||
|  | 		{ | ||
|  | 			pxCurrentCoRoutine = pxCoRoutine; | ||
|  | 			prvInitialiseCoRoutineLists(); | ||
|  | 		} | ||
|  | 
 | ||
|  | 		/* Check the priority is within limits. */ | ||
|  | 		if( uxPriority >= configMAX_CO_ROUTINE_PRIORITIES ) | ||
|  | 		{ | ||
|  | 			uxPriority = configMAX_CO_ROUTINE_PRIORITIES - 1; | ||
|  | 		} | ||
|  | 
 | ||
|  | 		/* Fill out the co-routine control block from the function parameters. */ | ||
|  | 		pxCoRoutine->uxState = corINITIAL_STATE; | ||
|  | 		pxCoRoutine->uxPriority = uxPriority; | ||
|  | 		pxCoRoutine->uxIndex = uxIndex; | ||
|  | 		pxCoRoutine->pxCoRoutineFunction = pxCoRoutineCode; | ||
|  | 
 | ||
|  | 		/* Initialise all the other co-routine control block parameters. */ | ||
|  | 		vListInitialiseItem( &( pxCoRoutine->xGenericListItem ) ); | ||
|  | 		vListInitialiseItem( &( pxCoRoutine->xEventListItem ) ); | ||
|  | 
 | ||
|  | 		/* Set the co-routine control block as a link back from the xListItem.
 | ||
|  | 		This is so we can get back to the containing CRCB from a generic item | ||
|  | 		in a list. */ | ||
|  | 		listSET_LIST_ITEM_OWNER( &( pxCoRoutine->xGenericListItem ), pxCoRoutine ); | ||
|  | 		listSET_LIST_ITEM_OWNER( &( pxCoRoutine->xEventListItem ), pxCoRoutine ); | ||
|  | 	 | ||
|  | 		/* Event lists are always in priority order. */ | ||
|  | 		listSET_LIST_ITEM_VALUE( &( pxCoRoutine->xEventListItem ), configMAX_PRIORITIES - ( portTickType ) uxPriority ); | ||
|  | 		 | ||
|  | 		/* Now the co-routine has been initialised it can be added to the ready
 | ||
|  | 		list at the correct priority. */ | ||
|  | 		prvAddCoRoutineToReadyQueue( pxCoRoutine ); | ||
|  | 
 | ||
|  | 		xReturn = pdPASS; | ||
|  | 	} | ||
|  | 	else | ||
|  | 	{		 | ||
|  | 		xReturn = errCOULD_NOT_ALLOCATE_REQUIRED_MEMORY; | ||
|  | 	} | ||
|  | 	 | ||
|  | 	return xReturn;	 | ||
|  | } | ||
|  | /*-----------------------------------------------------------*/ | ||
|  | 
 | ||
|  | void vCoRoutineAddToDelayedList( portTickType xTicksToDelay, xList *pxEventList ) | ||
|  | { | ||
|  | portTickType xTimeToWake; | ||
|  | 
 | ||
|  | 	/* Calculate the time to wake - this may overflow but this is
 | ||
|  | 	not a problem. */ | ||
|  | 	xTimeToWake = xCoRoutineTickCount + xTicksToDelay; | ||
|  | 
 | ||
|  | 	/* We must remove ourselves from the ready list before adding
 | ||
|  | 	ourselves to the blocked list as the same list item is used for | ||
|  | 	both lists. */ | ||
|  | 	uxListRemove( ( xListItem * ) &( pxCurrentCoRoutine->xGenericListItem ) ); | ||
|  | 
 | ||
|  | 	/* The list item will be inserted in wake time order. */ | ||
|  | 	listSET_LIST_ITEM_VALUE( &( pxCurrentCoRoutine->xGenericListItem ), xTimeToWake ); | ||
|  | 
 | ||
|  | 	if( xTimeToWake < xCoRoutineTickCount ) | ||
|  | 	{ | ||
|  | 		/* Wake time has overflowed.  Place this item in the
 | ||
|  | 		overflow list. */ | ||
|  | 		vListInsert( ( xList * ) pxOverflowDelayedCoRoutineList, ( xListItem * ) &( pxCurrentCoRoutine->xGenericListItem ) ); | ||
|  | 	} | ||
|  | 	else | ||
|  | 	{ | ||
|  | 		/* The wake time has not overflowed, so we can use the
 | ||
|  | 		current block list. */ | ||
|  | 		vListInsert( ( xList * ) pxDelayedCoRoutineList, ( xListItem * ) &( pxCurrentCoRoutine->xGenericListItem ) ); | ||
|  | 	} | ||
|  | 
 | ||
|  | 	if( pxEventList ) | ||
|  | 	{ | ||
|  | 		/* Also add the co-routine to an event list.  If this is done then the
 | ||
|  | 		function must be called with interrupts disabled. */ | ||
|  | 		vListInsert( pxEventList, &( pxCurrentCoRoutine->xEventListItem ) ); | ||
|  | 	} | ||
|  | } | ||
|  | /*-----------------------------------------------------------*/ | ||
|  | 
 | ||
|  | static void prvCheckPendingReadyList( void ) | ||
|  | { | ||
|  | 	/* Are there any co-routines waiting to get moved to the ready list?  These
 | ||
|  | 	are co-routines that have been readied by an ISR.  The ISR cannot access | ||
|  | 	the	ready lists itself. */ | ||
|  | 	while( listLIST_IS_EMPTY( &xPendingReadyCoRoutineList ) == pdFALSE ) | ||
|  | 	{ | ||
|  | 		corCRCB *pxUnblockedCRCB; | ||
|  | 
 | ||
|  | 		/* The pending ready list can be accessed by an ISR. */ | ||
|  | 		portDISABLE_INTERRUPTS(); | ||
|  | 		{	 | ||
|  | 			pxUnblockedCRCB = ( corCRCB * ) listGET_OWNER_OF_HEAD_ENTRY( (&xPendingReadyCoRoutineList) );			 | ||
|  | 			uxListRemove( &( pxUnblockedCRCB->xEventListItem ) ); | ||
|  | 		} | ||
|  | 		portENABLE_INTERRUPTS(); | ||
|  | 
 | ||
|  | 		uxListRemove( &( pxUnblockedCRCB->xGenericListItem ) ); | ||
|  | 		prvAddCoRoutineToReadyQueue( pxUnblockedCRCB );	 | ||
|  | 	} | ||
|  | } | ||
|  | /*-----------------------------------------------------------*/ | ||
|  | 
 | ||
|  | static void prvCheckDelayedList( void ) | ||
|  | { | ||
|  | corCRCB *pxCRCB; | ||
|  | 
 | ||
|  | 	xPassedTicks = xTaskGetTickCount() - xLastTickCount; | ||
|  | 	while( xPassedTicks ) | ||
|  | 	{ | ||
|  | 		xCoRoutineTickCount++; | ||
|  | 		xPassedTicks--; | ||
|  | 
 | ||
|  | 		/* If the tick count has overflowed we need to swap the ready lists. */ | ||
|  | 		if( xCoRoutineTickCount == 0 ) | ||
|  | 		{ | ||
|  | 			xList * pxTemp; | ||
|  | 
 | ||
|  | 			/* Tick count has overflowed so we need to swap the delay lists.  If there are
 | ||
|  | 			any items in pxDelayedCoRoutineList here then there is an error! */ | ||
|  | 			pxTemp = pxDelayedCoRoutineList; | ||
|  | 			pxDelayedCoRoutineList = pxOverflowDelayedCoRoutineList; | ||
|  | 			pxOverflowDelayedCoRoutineList = pxTemp; | ||
|  | 		} | ||
|  | 
 | ||
|  | 		/* See if this tick has made a timeout expire. */ | ||
|  | 		while( listLIST_IS_EMPTY( pxDelayedCoRoutineList ) == pdFALSE ) | ||
|  | 		{ | ||
|  | 			pxCRCB = ( corCRCB * ) listGET_OWNER_OF_HEAD_ENTRY( pxDelayedCoRoutineList ); | ||
|  | 
 | ||
|  | 			if( xCoRoutineTickCount < listGET_LIST_ITEM_VALUE( &( pxCRCB->xGenericListItem ) ) )				 | ||
|  | 			{			 | ||
|  | 				/* Timeout not yet expired. */																			 | ||
|  | 				break;																				 | ||
|  | 			}																						 | ||
|  | 
 | ||
|  | 			portDISABLE_INTERRUPTS(); | ||
|  | 			{ | ||
|  | 				/* The event could have occurred just before this critical
 | ||
|  | 				section.  If this is the case then the generic list item will | ||
|  | 				have been moved to the pending ready list and the following | ||
|  | 				line is still valid.  Also the pvContainer parameter will have | ||
|  | 				been set to NULL so the following lines are also valid. */ | ||
|  | 				uxListRemove( &( pxCRCB->xGenericListItem ) );											 | ||
|  | 
 | ||
|  | 				/* Is the co-routine waiting on an event also? */												 | ||
|  | 				if( pxCRCB->xEventListItem.pvContainer )													 | ||
|  | 				{															 | ||
|  | 					uxListRemove( &( pxCRCB->xEventListItem ) );											 | ||
|  | 				} | ||
|  | 			} | ||
|  | 			portENABLE_INTERRUPTS(); | ||
|  | 
 | ||
|  | 			prvAddCoRoutineToReadyQueue( pxCRCB );													 | ||
|  | 		}																									 | ||
|  | 	} | ||
|  | 
 | ||
|  | 	xLastTickCount = xCoRoutineTickCount; | ||
|  | } | ||
|  | /*-----------------------------------------------------------*/ | ||
|  | 
 | ||
|  | void vCoRoutineSchedule( void ) | ||
|  | { | ||
|  | 	/* See if any co-routines readied by events need moving to the ready lists. */ | ||
|  | 	prvCheckPendingReadyList(); | ||
|  | 
 | ||
|  | 	/* See if any delayed co-routines have timed out. */ | ||
|  | 	prvCheckDelayedList(); | ||
|  | 
 | ||
|  | 	/* Find the highest priority queue that contains ready co-routines. */ | ||
|  | 	while( listLIST_IS_EMPTY( &( pxReadyCoRoutineLists[ uxTopCoRoutineReadyPriority ] ) ) ) | ||
|  | 	{ | ||
|  | 		if( uxTopCoRoutineReadyPriority == 0 ) | ||
|  | 		{ | ||
|  | 			/* No more co-routines to check. */ | ||
|  | 			return; | ||
|  | 		} | ||
|  | 		--uxTopCoRoutineReadyPriority; | ||
|  | 	} | ||
|  | 
 | ||
|  | 	/* listGET_OWNER_OF_NEXT_ENTRY walks through the list, so the co-routines
 | ||
|  | 	 of the	same priority get an equal share of the processor time. */ | ||
|  | 	listGET_OWNER_OF_NEXT_ENTRY( pxCurrentCoRoutine, &( pxReadyCoRoutineLists[ uxTopCoRoutineReadyPriority ] ) ); | ||
|  | 
 | ||
|  | 	/* Call the co-routine. */ | ||
|  | 	( pxCurrentCoRoutine->pxCoRoutineFunction )( pxCurrentCoRoutine, pxCurrentCoRoutine->uxIndex ); | ||
|  | 
 | ||
|  | 	return; | ||
|  | } | ||
|  | /*-----------------------------------------------------------*/ | ||
|  | 
 | ||
|  | static void prvInitialiseCoRoutineLists( void ) | ||
|  | { | ||
|  | unsigned portBASE_TYPE uxPriority; | ||
|  | 
 | ||
|  | 	for( uxPriority = 0; uxPriority < configMAX_CO_ROUTINE_PRIORITIES; uxPriority++ ) | ||
|  | 	{ | ||
|  | 		vListInitialise( ( xList * ) &( pxReadyCoRoutineLists[ uxPriority ] ) ); | ||
|  | 	} | ||
|  | 
 | ||
|  | 	vListInitialise( ( xList * ) &xDelayedCoRoutineList1 ); | ||
|  | 	vListInitialise( ( xList * ) &xDelayedCoRoutineList2 ); | ||
|  | 	vListInitialise( ( xList * ) &xPendingReadyCoRoutineList ); | ||
|  | 
 | ||
|  | 	/* Start with pxDelayedCoRoutineList using list1 and the
 | ||
|  | 	pxOverflowDelayedCoRoutineList using list2. */ | ||
|  | 	pxDelayedCoRoutineList = &xDelayedCoRoutineList1; | ||
|  | 	pxOverflowDelayedCoRoutineList = &xDelayedCoRoutineList2; | ||
|  | } | ||
|  | /*-----------------------------------------------------------*/ | ||
|  | 
 | ||
|  | signed portBASE_TYPE xCoRoutineRemoveFromEventList( const xList *pxEventList ) | ||
|  | { | ||
|  | corCRCB *pxUnblockedCRCB; | ||
|  | signed portBASE_TYPE xReturn; | ||
|  | 
 | ||
|  | 	/* This function is called from within an interrupt.  It can only access
 | ||
|  | 	event lists and the pending ready list.  This function assumes that a | ||
|  | 	check has already been made to ensure pxEventList is not empty. */ | ||
|  | 	pxUnblockedCRCB = ( corCRCB * ) listGET_OWNER_OF_HEAD_ENTRY( pxEventList ); | ||
|  | 	uxListRemove( &( pxUnblockedCRCB->xEventListItem ) ); | ||
|  | 	vListInsertEnd( ( xList * ) &( xPendingReadyCoRoutineList ), &( pxUnblockedCRCB->xEventListItem ) ); | ||
|  | 
 | ||
|  | 	if( pxUnblockedCRCB->uxPriority >= pxCurrentCoRoutine->uxPriority ) | ||
|  | 	{ | ||
|  | 		xReturn = pdTRUE; | ||
|  | 	} | ||
|  | 	else | ||
|  | 	{ | ||
|  | 		xReturn = pdFALSE; | ||
|  | 	} | ||
|  | 
 | ||
|  | 	return xReturn; | ||
|  | } | ||
|  | 
 |