Subversion Repositories openrisc_2011-10-31

/*  Shared Memory Lock Routines

 *

 *  This shared memory locked queue support routine need to be

 *  able to lock the specified locked queue.  Interrupts are

 *  disabled while the queue is locked to prevent preemption

 *  and deadlock when two tasks poll for the same lock.

 *  previous level.

 *

 *  COPYRIGHT (c) 1989-1997.

 *  On-Line Applications Research Corporation (OAR).

 *  Copyright assigned to U.S. Government, 1994.

 *

 *  The license and distribution terms for this file may in

 *  the file LICENSE in this distribution or at

 *  http://www.OARcorp.com/rtems/license.html.

 *

 *  $Id: lock.c,v 1.2 2001-09-27 12:01:02 chris Exp $

 */

#include <rtems.h>

#include <bsp.h>

#include <shm_driver.h>

typedef volatile unsigned int volint;

/*

 *  Shm_Initialize_lock

 *

 *  Initialize the lock for the specified locked queue.

 */

void Shm_Initialize_lock(

  Shm_Locked_queue_Control *lq_cb

)

{

  /* nothing required -- done implicitly by device tree */

}

/*  void _Shm_Lock( &lq_cb )

 *

 *  This shared memory locked queue support routine locks the

 *  specified locked queue.  It disables interrupts to prevent

 *  a deadlock condition.

 */

void Shm_Lock(

  Shm_Locked_queue_Control *lq_cb

)

{

  volint *p = (volint *)0xc0010000;

  (void) p[1];

}

/*

 *  Shm_Unlock

 *

 *  Unlock the lock for the specified locked queue.

 */

void Shm_Unlock(

  Shm_Locked_queue_Control *lq_cb

)

{

  volint *p = (volint *)0xc0010000;

  (void) p[2];

}