siacs.c
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/*====================================================================
* siacs.c
*
* Copyright 1995, Silicon Graphics, Inc.
* All Rights Reserved.
*
* This is UNPUBLISHED PROPRIETARY SOURCE CODE of Silicon Graphics,
* Inc.; the contents of this file may not be disclosed to third
* parties, copied or duplicated in any form, in whole or in part,
* without the prior written permission of Silicon Graphics, Inc.
*
* RESTRICTED RIGHTS LEGEND:
* Use, duplication or disclosure by the Government is subject to
* restrictions as set forth in subdivision (c)(1)(ii) of the Rights
* in Technical Data and Computer Software clause at DFARS
* 252.227-7013, and/or in similar or successor clauses in the FAR,
* DOD or NASA FAR Supplement. Unpublished - rights reserved under the
* Copyright Laws of the United States.
*====================================================================*/
/**************************************************************************
*
* $Revision: 1.1.1.2 $
* $Date: 2002/10/29 08:06:43 $
* $Source: /root/leakn64/depot/rf/sw/n64os20l/libultra/monegi/si/siacs.c,v $
*
* Description:
* This file contains routines to get access to the SI device.
*
**************************************************************************/
#include "osint.h"
#include "siint.h"
#define NUM_ACCESS_MESG 1
/* Access queue used for mutual exclusion on SI */
static OSMesg siAccessBuf[NUM_ACCESS_MESG];
OSMesgQueue __osSiAccessQueue;
int __osSiAccessQueueEnabled = 0;
/*
* Name: __osSiCreateAccessQueue
*
* Description:
*
*
* Globals Referenced:
* None
*/
void
__osSiCreateAccessQueue(void)
{
__osSiAccessQueueEnabled = 1;
osCreateMesgQueue(&__osSiAccessQueue, siAccessBuf, NUM_ACCESS_MESG);
/* Initialize the access queue with a resource token */
(void)osSendMesg(&__osSiAccessQueue, (OSMesg)0, OS_MESG_NOBLOCK);
}
/*
* Name: __osSiGetAccess
*
* Description:
* Get the access right to SI by blocking on the access queue.
*
* Globals Referenced:
* __osSiAccessQueue
*/
void
__osSiGetAccess(void)
{
OSMesg dummyMesg;
/* Create access message queue if haven't done so */
if (!__osSiAccessQueueEnabled) {
__osSiCreateAccessQueue();
}
(void)osRecvMesg(&__osSiAccessQueue, &dummyMesg, OS_MESG_BLOCK);
}
/*
* Name: __osSiRelAccess
*
* Description:
* Release the access right to SI by sending a mesg to the access queue.
*
* Globals Referenced:
* __osSiAccessQueue
*/
void
__osSiRelAccess(void)
{
(void)osSendMesg(&__osSiAccessQueue, (OSMesg)0, OS_MESG_NOBLOCK);
}