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 * This is UNPUBLISHED PROPRIETARY SOURCE CODE of Silicon Graphics,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 Unpublished - rights reserved under the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

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

extern OSDevMgr		__osPiDevMgr;
extern OSMesgQueue	*osPiGetCmdQueue(void);


/*
 * Name:   osPiStartDma
 *
 * Description:
 *	Set up a DMA transfer between RDRAM and PI device address space by
 *	sending a request to PIM. If the request priority is OS_MESG_PRI_HIGH,
 *	jam the message to the front of PIM command queue; otherwise, simply
 *	send it to the queue. If PIM is not active, return a "-1"; otherwise,
 *	return the status of either osSendMesg() or osJamMesg(). 
 *
 * Globals Referenced: 
 *	__osPiDevMgr
 */
s32
osPiStartDma(OSIoMesg *mb, s32 priority, s32 direction, u32 devAddr, 
		void *dramAddr, u32 size, OSMesgQueue *mq)
{
    register s32 ret;

    /* 
     * Check for existence of PI Manager 
     */
    if (!__osPiDevMgr.active) {
#ifdef _DEBUG
	__osError(ERR_OSPISTARTDMA_PIMGR, 0);
#endif
        return(-1);
    }

#ifdef _DEBUG
    /*
     * Check for valid message priority
     */
    if ((priority != OS_MESG_PRI_NORMAL) &&
	(priority != OS_MESG_PRI_HIGH)) {
	__osError(ERR_OSPISTARTDMA_PRI, 1, priority);
	return(-1);
    }

    /*
     * Check for valid direction
     */
    if ((direction != OS_READ) && (direction != OS_WRITE)) {
	__osError(ERR_OSPISTARTDMA_DIR, 1, direction);
	return(-1);
    }

    /*
     * Need 16-bit alignment for ROM
     */
    if (devAddr & 0x1) {
	__osError(ERR_OSPISTARTDMA_DEVADDR, 1, devAddr);
	return(-1);
    }

    /*
     * Need 64-bit alignment for RDRAM
     */
    if ((u32)dramAddr & 0x7) {
	__osError(ERR_OSPISTARTDMA_ADDR, 1, dramAddr);
	return(-1);
    }

    /*
     * Size must be a multiple of 2 bytes
     */
    if (size & 0x1) {
	__osError(ERR_OSPISTARTDMA_SIZE, 1, size);
	return(-1);
    }

    /*
     * Check for valid range: 0 < size <= 16 MBytes
     */
    if ((size == 0) || (size > (16*1024*1024))) {
	__osError(ERR_OSPISTARTDMA_RANGE, 1, size);
	return(-1);
    }
#endif

    /* 
     * Fill up I/O request message 
     */
    if (direction == OS_READ)
        mb->hdr.type   = OS_MESG_TYPE_DMAREAD;
    else
        mb->hdr.type   = OS_MESG_TYPE_DMAWRITE;
    mb->hdr.pri      = (u8)priority;
    mb->hdr.retQueue = mq;
    mb->dramAddr     = dramAddr;
    mb->devAddr      = devAddr;
    mb->size         = size;
    mb->piHandle     = NULL;

    /*
     * Send it to Peripheral Interface Manager 
     */

    if (priority == OS_MESG_PRI_HIGH)
        ret = osJamMesg(osPiGetCmdQueue(), (void *)mb, OS_MESG_NOBLOCK);
    else
        ret = osSendMesg(osPiGetCmdQueue(), (void *)mb, OS_MESG_NOBLOCK);

    return(ret);

}  /* osPiStartDma */