ucos.c

各种硬件平台上的us OS移植实例(arm6)

		OS_EXIT_CRITICAL();
		*err = OS_NO_ERR;
		return(msg);		/* return mailbox content */
		}
	
	/* ELSE */
	
	/* message not available, task will pend (sleep on mailbox) */
	
	OSTCBCur->OSTCBStat = OS_STAT_MBOX;
	OSTCBCur->OSTCBDly = timeout;
	
	/* suspend task */
	if ((OSRdyTbl[OSTCBCur->OSTCBY] &= ~OSTCBCur->OSTCBBitX) == 0)
		{
		OSRdyGrp &= ~OSTCBCur->OSTCBBitY;
		}
	
	pevent->OSEventTbl[OSTCBCur->OSTCBY] |= OSTCBCur->OSTCBBitX;
	pevent->OSEventGrp 					 |= OSTCBCur->OSTCBBitY;

	OS_EXIT_CRITICAL();

	OSSched();			/* find next task ready to run */

	OS_ENTER_CRITICAL();
	
	if (OSTCBCur->OSTCBStat == OS_STAT_MBOX)
		{
		/* still pending on mailbox: timeout */
		if ((pevent->OSEventTbl[OSTCBCur->OSTCBY] &= ~OSTCBCur->OSTCBBitX) == 0)
			{
			pevent->OSEventGrp &= ~OSTCBCur->OSTCBBitY;
			}

		OSTCBCur->OSTCBStat = OS_STAT_RDY;		/* set status to ready */
		OSTCBCur->OSTCBEventPtr = (OS_EVENT *)0;	/* no longer waiting for event */

		msg = (void *)0;		/* set message content to null */

		OS_EXIT_CRITICAL();

		*err = OS_TIMEOUT;		/* signal time'ed out */
		}
	else
		{
		msg = pevent->OSEventPtr;		/* message received */
		pevent->OSEventPtr = (void *)0;	/* clear the mailbox */

		OS_EXIT_CRITICAL();

		*err = OS_NO_ERR;
		}

 return(msg);
}
/*
 * O S M b o x P o s t
 *
 * post mbox message
 */
uint	OSMboxPost(OS_EVENT *pevent, void *msg)
{
	OS_ENTER_CRITICAL();		/* make sure mailbox doesn't contain a message */

	if (pevent->OSEventPtr != (void *)0)
		{
		OS_EXIT_CRITICAL();
		return(OS_MBOX_FULL);
		}
		
	/* ELSE */
	
	pevent->OSEventPtr = msg;	/* place message in mailbox */
	
	if (pevent->OSEventGrp)		/* see if any task is pending on the mailbox */
		{
		OS_EXIT_CRITICAL();	/* resume highest priority task pending on mailbox */

		OSEventTaskResume(pevent);

		OSSched();			/* Find highest priority task ready to run */
		}
	else
		{
		OS_EXIT_CRITICAL();
		}

 return(OS_NO_ERR);
}
/*
 * I R Q M b o x P o s t
 *
 * post mbox message
 */
uint	IRQMboxPost(OS_EVENT *pevent, void *msg)
{
 OS_TCB	*ptcb;
 uint	 x;
 uint	 y;
 uint	 bitx;
 uint	 bity;
 uint	 p;

	if (pevent->OSEventPtr != (void *)0)
		{
		return(OS_MBOX_FULL);
		}
		
	/* ELSE */
	
	pevent->OSEventPtr = msg;	/* place message in mailbox */
	
	if (pevent->OSEventGrp)		/* see if any task is pending on the mailbox */
		{
		y	 = OSUnMapTbl[pevent->OSEventGrp];	/* find highest priority task pending on event */
		bity = OSMapTbl[y];
		x	 = OSUnMapTbl[pevent->OSEventTbl[y]];
		bitx = OSMapTbl[x];
		p	 = (y << 3) + x;
		
		if ((pevent->OSEventTbl[y] &= ~bitx) == 0)	/* remove this task from waiting list */
			{
			pevent->OSEventGrp &= ~bity;
			}
		
		ptcb				= OSTCBPrioTbl[p];	/* pointer to new task */ 
		ptcb->OSTCBDly		= 0;				/* reset timeout */
		ptcb->OSTCBStat		= OS_STAT_RDY;		/* task is ready to run */
		ptcb->OSTCBEventPtr = (OS_EVENT *)0;	/* unlink control block */
		
		OSRdyGrp		|= bity;				/* put task in ready to run list */
		OSRdyTbl[y]		|= bitx;
		}
	
 return(OS_NO_ERR);
}
/*
 * O S Q C r e a t e
 *
 * create a queue
 */
OS_EVENT	*OSQCreate(void **start, uint size)
{
 OS_EVENT	*pevent;
 OS_Q		*pq;

	OS_ENTER_CRITICAL();
	
	pevent = OSEventFreeList;	/* get next free event control block */

	if (OSEventFreeList)		/* update free list */
		{
		OSEventFreeList = (OS_EVENT *)OSEventFreeList->OSEventPtr;
		}
		
	if (pevent == (OS_EVENT *)0)
		{
		OS_EXIT_CRITICAL();		/* ran out of event CB */
		return(pevent);	
		}
		
	/* ELSE */
	
	pq = OSQFreeList;			/* get a free queue control block */
	
	if (OSQFreeList != (OS_Q *)0)
		{
		OSQFreeList = OSQFreeList->OSQPtr;
		}
	
	if (pq == (OS_Q *)0)		/* was there a free block ? */
		{
		pevent->OSEventPtr = (void *)OSEventFreeList;	/* NO */
		OSEventFreeList = pevent;	/* ran out of queue CB return event CB to free list */
		OS_EXIT_CRITICAL();
		return((OS_EVENT *)0);
		}
	
	/* ELSE */
	
	OS_EXIT_CRITICAL();

	pq->OSQStart		  = start;			/* initialize the queue */
	pq->OSQEnd			  = &start[size];
	pq->OSQIn			  = start;
	pq->OSQOut			  = start;
	pq->OSQSize			  = size;
	pq->OSQEntries		  = 0;
	pevent->OSEventPtr	  = pq;
	pevent->OSEventGrp	  = 0;
	pevent->OSEventTbl[0] = 0;
	pevent->OSEventTbl[1] = 0;
	pevent->OSEventTbl[2] = 0;
	pevent->OSEventTbl[3] = 0;
	pevent->OSEventTbl[4] = 0;
	pevent->OSEventTbl[5] = 0;
	pevent->OSEventTbl[6] = 0;
	pevent->OSEventTbl[7] = 0;

 return(pevent);
}
/*
 * O S Q P e n d
 *
 * pend for message from a queue
 */
void	*OSQPend(OS_EVENT *pevent, uint timeout, uint *err)
{
 void	*msg;
 OS_Q	*pq;

	OS_ENTER_CRITICAL();

	pq = (OS_Q *)pevent->OSEventPtr;

	if (pq->OSQEntries != 0)	/* check if the queue already has a message */
		{
		msg = *pq->OSQOut++;	/* extract the message */
		pq->OSQEntries--;		/* update message counter */

		if (pq->OSQOut == pq->OSQEnd)	/* wrap around Out pointer if reached end */
			{
			pq->OSQOut = pq->OSQStart;
			}

		OS_EXIT_CRITICAL();

		*err = OS_NO_ERR;
		return(msg);
		}
		
	/* ELSE */
	
	/* no messages available, sleep on the queue */

	OSTCBCur->OSTCBStat = OS_STAT_Q;
	OSTCBCur->OSTCBDly = timeout;

	/* suspend task */
	if ((OSRdyTbl[OSTCBCur->OSTCBY] &= ~OSTCBCur->OSTCBBitX) == 0)
		{
		OSRdyGrp &= ~OSTCBCur->OSTCBBitY;
		}
			
	pevent->OSEventTbl[OSTCBCur->OSTCBY] |= OSTCBCur->OSTCBBitX;	/* put task in waiting list */
	pevent->OSEventGrp					 |= OSTCBCur->OSTCBBitY;
	
	OS_EXIT_CRITICAL();
	

	OSSched();			/* find next highest priority task ready to run */

	OS_ENTER_CRITICAL();

	if (OSTCBCur->OSTCBStat == OS_STAT_Q)	/* still pending on queue: timeout */
		{
		if ((pevent->OSEventTbl[OSTCBCur->OSTCBY] &= ~OSTCBCur->OSTCBBitX) == 0)
			{
			pevent->OSEventGrp &= ~OSTCBCur->OSTCBBitY;
			}

		OSTCBCur->OSTCBStat		= OS_STAT_RDY;		/* set status to ready */
		OSTCBCur->OSTCBEventPtr = (OS_EVENT *)0;	/* no longer waiting for event */

		msg = (void *)0;		/* set message content to null */

		OS_EXIT_CRITICAL();

		*err = OS_TIMEOUT;		/* signal time'ed out */
		}
	else
		{

		msg = *pq->OSQOut++;			/* message received */
		pq->OSQEntries--;				/* update message counter */

		if (pq->OSQOut == pq->OSQEnd)	/* wrap around Out pointer if reached end */
			{
			pq->OSQOut = pq->OSQStart;
			}

		OS_EXIT_CRITICAL();

		*err = OS_NO_ERR;
		}
	
	return(msg);
}
/*
 * O S Q P o s t
 *
 * post a message to a queue
 */
uint	OSQPost(OS_EVENT *pevent, void *msg)
{
 OS_Q	*pq;

	OS_ENTER_CRITICAL();

	pq = (OS_Q *)pevent->OSEventPtr;	/* point to queue control block */

	if (pq->OSQEntries >= pq->OSQSize)	/* make sure the queue is not full */
		{
		OS_EXIT_CRITICAL();
		return(OS_Q_FULL);
		}
		
	/* ELSE */

	*pq->OSQIn++ = msg;				/* insert message into queue */
	pq->OSQEntries++;				/* update number of entries in queue */

	if (pq->OSQIn == pq->OSQEnd)
		{
		pq->OSQIn = pq->OSQStart;	/* wrap around In pointer if reached end */
		}

	if (pevent->OSEventGrp)		/* see if any task is pending on the mailbox */
		{
		OS_EXIT_CRITICAL();

		OSEventTaskResume(pevent);	/* resume highest priority task pending on mailbox */
		OSSched();					/* find highest priority task pending on queue */
		}
	else
		{
		OS_EXIT_CRITICAL();
		}

 return(OS_NO_ERR);
}
/*
 * O S E v e n t T a s k R e s u m e
 */
void	OSEventTaskResume(OS_EVENT *pevent)
{
 OS_TCB	*ptcb;
 uint	 x;
 uint	 y;
 uint	 bitx;
 uint	 bity;
 uint	 p;

	OS_ENTER_CRITICAL(); 

	y	 = OSUnMapTbl[pevent->OSEventGrp];	/* find highest priority task pending on event */
	bity = OSMapTbl[y];
	x	 = OSUnMapTbl[pevent->OSEventTbl[y]];
	bitx = OSMapTbl[x];
	p	 = (y << 3) + x;

	if ((pevent->OSEventTbl[y] &= ~bitx) == 0)	/* remove this task from waiting list */
		{
		pevent->OSEventGrp &= ~bity;
		}

	ptcb				= OSTCBPrioTbl[p];	/* pointer to new task */ 
	ptcb->OSTCBDly		= 0;				/* reset timeout */
	ptcb->OSTCBStat		= OS_STAT_RDY;		/* task is ready to run */
	ptcb->OSTCBEventPtr = (OS_EVENT *)0;	/* unlink control block */

	OSRdyGrp		|= bity;				/* put task in ready to run list */
	OSRdyTbl[y]		|= bitx;

	OS_EXIT_CRITICAL(); 
}
/*
 * O S T a s k C r e a t e
 *
 * create a task
 *
 *   This differs from the code in manual because the 1st four parameters are
 * passed in a1-a4 respectively. Therefore pdata is NOT passed on the stack
 * but in register a1.
 *   Also TASK's are created so that the LR contains the "return" location,
 * which allows the context switch to do the same for starting a new task as
 * well as continuing with a preempted one.
 */
int		OSTaskCreate(PTV task, void *pdata, void *ptsk, uint prio)
{
 void	*stk;
 int	 err;

	OS_ENTER_CRITICAL(); 

	if (OSTCBPrioTbl[prio] != (OS_TCB *)0)
		{
		OS_EXIT_CRITICAL(); 
		return(OS_PRIO_EXIST);	/* only one task allowed at its priority */
		}
		
	/* ELSE build a context for the new task */
	
	OS_EXIT_CRITICAL(); 
	
	stk = InitTask(ptsk, pdata, task);	/* initialise the task at pstk */

	err = OSTCBInit(prio, (void *)stk);

	if ((err == OS_NO_ERR) && OSRunning) 
		{
		OSSched();
		}

 return(err);
}

/*
 * A R M I n s t a l l I R Q H a n d l e r
 *
 * This routine allows a uC/OS IRQ source bit ISR to be installed in
 * the handler vector table. NOTE: The vector table is *TOTALLY*
 * seperate from the C-Demon IRQ vector table, and is a uC/OS
 * resource.
 */
IRQHandlerFn ARMInstallIRQHandler(int slot,IRQHandlerFn newfn)
{
 IRQHandlerFn old = NULL ;

 if ((slot >= 0) && (slot < NUMIRQS))
  {
   old = IRQvectors[slot] ;
   IRQvectors[slot] = newfn ;
  }

 return(old) ;
}

/*
 * A R M I n s t a l l F I Q H a n d l e r
 *
 * This routine allows a uC/OS FIQ source bit ISR to be installed in
 * the handler vector table. NOTE: The vector table is *TOTALLY*
 * seperate from the C-Demon FIQ vector table, and is a uC/OS
 * resource.
 */
FIQHandlerFn ARMInstallFIQHandler(int slot,FIQHandlerFn newfn)
{
 FIQHandlerFn old = NULL ;

 if ((slot >= 0) && (slot < NUMFIQS))
  {
   old = FIQvectors[slot] ;
   FIQvectors[slot] = newfn ;
  }

 return(old) ;
}

/*> EOF ucos.c <*/