dpsetnextbuf.c 2.39 KB

/*====================================================================
 * dpsetnextbuf.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 * This is UNPUBLISHED PROPRIETARY SOURCE CODE of Silicon Graphics,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 Unpublished - rights reserved under the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/rdp/dpsetnextbuf.c,v $
 *
 **************************************************************************/


#include "osint.h"
#include "rcp.h"
#include "assert.h"


/*
 * Name:   osDpSetNextBuffer
 *
 * Description:
 *	Set up the next DP transfer from RDRAM.  bufPtr points to the
 *	buffer in RDRAM and size specifies the number of bytes to transfer.
 *	Note that the 	buffer address must be 64-bit aligned and that size
 *	must *	be a multiple of 8 bytes.
 *
 *	If DP is busy, return a "-1" and abort the operation.
 *
 * Globals Referenced: 
 *	None
 */
s32
osDpSetNextBuffer(void *bufPtr, u64 size)
{

    register u32 stat;

#ifdef _DEBUG
    /* Check for 64-bit alignment in buffer address and size */
    if ((u32)bufPtr & 0x7) {
	__osError(ERR_OSDPSETNEXTBUFFER_ADDR, 1, bufPtr);
	return(-1);
    }
    if (size & 0x7) {
	__osError(ERR_OSDPSETNEXTBUFFER_SIZE, 1, size);
	return(-1);
    }
#endif

    if (__osDpDeviceBusy())
        return(-1);

    IO_WRITE(DPC_STATUS_REG, DPC_CLR_XBUS_DMEM_DMA);

    /* Need to wait for xbus_dmem_dma set/cleared */
    while (1) {
        stat = IO_READ(DPC_STATUS_REG);
        if (!(stat & DPC_STATUS_XBUS_DMEM_DMA)) break;
    }

    IO_WRITE(DPC_START_REG, osVirtualToPhysical(bufPtr));
    IO_WRITE(DPC_END_REG, osVirtualToPhysical(bufPtr)+size);

    return(0);

}  /* osDpSetNextBuffer */