path: root/linux-core/i810_dma.c

/* i810_dma.c -- DMA support for the i810 -*- linux-c -*-
 * Created: Mon Dec 13 01:50:01 1999 by jhartmann@precisioninsight.com
 *
 * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
 * All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 *
 * Authors: Rickard E. (Rik) Faith <faith@valinux.com>
 *	    Jeff Hartmann <jhartmann@valinux.com>
 *          Keith Whitwell <keith@tungstengraphics.com>
 *
 */

#include "drmP.h"
#include "drm.h"
#include "i810_drm.h"
#include "i810_drv.h"
#include <linux/interrupt.h>	/* For task queue support */
#include <linux/delay.h>
#include <linux/pagemap.h>

#ifdef DO_MUNMAP_4_ARGS
#define DO_MUNMAP(m, a, l)	do_munmap(m, a, l, 1)
#else
#define DO_MUNMAP(m, a, l)	do_munmap(m, a, l)
#endif

#define I810_BUF_FREE		2
#define I810_BUF_CLIENT		1
#define I810_BUF_HARDWARE      	0

#define I810_BUF_UNMAPPED 0
#define I810_BUF_MAPPED   1

static inline void i810_print_status_page(drm_device_t *dev)
{
   	drm_device_dma_t *dma = dev->dma;
      	drm_i810_private_t *dev_priv = dev->dev_private;
	u32 *temp = dev_priv->hw_status_page;
   	int i;

   	DRM_DEBUG(  "hw_status: Interrupt Status : %x\n", temp[0]);
   	DRM_DEBUG(  "hw_status: LpRing Head ptr : %x\n", temp[1]);
   	DRM_DEBUG(  "hw_status: IRing Head ptr : %x\n", temp[2]);
      	DRM_DEBUG(  "hw_status: Reserved : %x\n", temp[3]);
	DRM_DEBUG(  "hw_status: Last Render: %x\n", temp[4]);
   	DRM_DEBUG(  "hw_status: Driver Counter : %d\n", temp[5]);
   	for(i = 6; i < dma->buf_count + 6; i++) {
	   	DRM_DEBUG( "buffer status idx : %d used: %d\n", i - 6, temp[i]);
	}
}

static drm_buf_t *i810_freelist_get(drm_device_t *dev)
{
   	drm_device_dma_t *dma = dev->dma;
	int		 i;
   	int 		 used;

	/* Linear search might not be the best solution */

   	for (i = 0; i < dma->buf_count; i++) {
	   	drm_buf_t *buf = dma->buflist[ i ];
	   	drm_i810_buf_priv_t *buf_priv = buf->dev_private;
		/* In use is already a pointer */
	   	used = cmpxchg(buf_priv->in_use, I810_BUF_FREE,
			       I810_BUF_CLIENT);
		if (used == I810_BUF_FREE) {
			return buf;
		}
	}
   	return NULL;
}

/* This should only be called if the buffer is not sent to the hardware
 * yet, the hardware updates in use for us once its on the ring buffer.
 */

static int i810_freelist_put(drm_device_t *dev, drm_buf_t *buf)
{
   	drm_i810_buf_priv_t *buf_priv = buf->dev_private;
   	int used;

   	/* In use is already a pointer */
   	used = cmpxchg(buf_priv->in_use, I810_BUF_CLIENT, I810_BUF_FREE);
	if (used != I810_BUF_CLIENT) {
	   	DRM_ERROR("Freeing buffer thats not in use : %d\n", buf->idx);
	   	return -EINVAL;
	}

   	return 0;
}

int i810_mmap_buffers(struct file *filp, struct vm_area_struct *vma)
{
	drm_file_t	    *priv	  = filp->private_data;
	drm_device_t	    *dev;
	drm_i810_private_t  *dev_priv;
	drm_buf_t           *buf;
	drm_i810_buf_priv_t *buf_priv;

	lock_kernel();
	dev	 = priv->dev;
	dev_priv = dev->dev_private;
	buf      = dev_priv->mmap_buffer;
	buf_priv = buf->dev_private;

	vma->vm_flags |= (VM_IO | VM_DONTCOPY);
	vma->vm_file = filp;

   	buf_priv->currently_mapped = I810_BUF_MAPPED;
	unlock_kernel();

	if (remap_page_range(DRM_RPR_ARG(vma) vma->vm_start,
			     VM_OFFSET(vma),
			     vma->vm_end - vma->vm_start,
			     vma->vm_page_prot)) return -EAGAIN;
	return 0;
}

static int i810_map_buffer(drm_buf_t *buf, struct file *filp)
{
	drm_file_t	  *priv	  = filp->private_data;
	drm_device_t	  *dev	  = priv->dev;
	drm_i810_buf_priv_t *buf_priv = buf->dev_private;
      	drm_i810_private_t *dev_priv = dev->dev_private;
	int retcode = 0;

	if (buf_priv->currently_mapped == I810_BUF_MAPPED) 
		return -EINVAL;

	down_write( &current->mm->mmap_sem );
	dev_priv->mmap_buffer = buf;
	buf_priv->virtual = (void *)do_mmap(filp, 0, buf->total,
					    PROT_READ|PROT_WRITE,
					    MAP_SHARED,
					    buf->bus_address);
	dev_priv->mmap_buffer = NULL;

	if ((unsigned long)buf_priv->virtual > -1024UL) {
		/* Real error */
		DRM_ERROR("mmap error\n");
		retcode = (signed int)buf_priv->virtual;
		buf_priv->virtual = NULL;
	}
	up_write( &current->mm->mmap_sem );

	return retcode;
}

static int i810_unmap_buffer(drm_buf_t *buf)
{
	drm_i810_buf_priv_t *buf_priv = buf->dev_private;
	int retcode = 0;

	if (buf_priv->currently_mapped != I810_BUF_MAPPED)
		return -EINVAL;

	down_write(&current->mm->mmap_sem);
	retcode = DO_MUNMAP(current->mm,
			    (unsigned long)buf_priv->virtual,
			    (size_t) buf->total);
	up_write(&current->mm->mmap_sem);

   	buf_priv->currently_mapped = I810_BUF_UNMAPPED;
   	buf_priv->virtual = NULL;

	return retcode;
}

static int i810_dma_get_buffer(drm_device_t *dev, drm_i810_dma_t *d,
			       struct file *filp)
{
	drm_buf_t	  *buf;
	drm_i810_buf_priv_t *buf_priv;
	int retcode = 0;

	buf = i810_freelist_get(dev);
	if (!buf) {
		retcode = -ENOMEM;
	   	DRM_DEBUG("retcode=%d\n", retcode);
		return retcode;
	}

	retcode = i810_map_buffer(buf, filp);
	if (retcode) {
		i810_freelist_put(dev, buf);
	   	DRM_ERROR("mapbuf failed, retcode %d\n", retcode);
		return retcode;
	}
	buf->filp = filp;
	buf_priv = buf->dev_private;
	d->granted = 1;
   	d->request_idx = buf->idx;
   	d->request_size = buf->total;
   	d->virtual = buf_priv->virtual;

	return retcode;
}

int i810_dma_cleanup(drm_device_t *dev)
{
	drm_device_dma_t *dma = dev->dma;

	/* Make sure interrupts are disabled here because the uninstall ioctl
	 * may not have been called from userspace and after dev_private
	 * is freed, it's too late.
	 */
	if (drm_core_check_feature(dev, DRIVER_HAVE_IRQ) && dev->irq_enabled)
		drm_irq_uninstall(dev);

	if (dev->dev_private) {
		int i;
	   	drm_i810_private_t *dev_priv =
	     		(drm_i810_private_t *) dev->dev_private;

		if (dev_priv->ring.virtual_start) {
		   	drm_ioremapfree((void *) dev_priv->ring.virtual_start,
					 dev_priv->ring.Size, dev);
		}
	   	if (dev_priv->hw_status_page) {
		   	pci_free_consistent(dev->pdev, PAGE_SIZE,
					    dev_priv->hw_status_page,
					    dev_priv->dma_status_page);
		   	/* Need to rewrite hardware status page */
		   	I810_WRITE(0x02080, 0x1ffff000);
		}
	   	drm_free(dev->dev_private, sizeof(drm_i810_private_t),
			 DRM_MEM_DRIVER);
	   	dev->dev_private = NULL;

		for (i = 0; i < dma->buf_count; i++) {
			drm_buf_t *buf = dma->buflist[ i ];
			drm_i810_buf_priv_t *buf_priv = buf->dev_private;
			if ( buf_priv->kernel_virtual && buf->total )
				drm_ioremapfree(buf_priv->kernel_virtual, buf->total, dev);
		}
	}
   	return 0;
}

static int i810_wait_ring(drm_device_t *dev, int n)
{
   	drm_i810_private_t *dev_priv = dev->dev_private;
   	drm_i810_ring_buffer_t *ring = &(dev_priv->ring);
   	int iters = 0;
   	unsigned long end;
	unsigned int last_head = I810_READ(LP_RING + RING_HEAD) & HEAD_ADDR;

	end = jiffies + (HZ*3);
   	while (ring->space < n) {
	   	ring->head = I810_READ(LP_RING + RING_HEAD) & HEAD_ADDR;
	   	ring->space = ring->head - (ring->tail+8);
		if (ring->space < 0) ring->space += ring->Size;
	   
		if (ring->head != last_head) {
			end = jiffies + (HZ*3);
			last_head = ring->head;
		}
	  
	   	iters++;
		if (time_before(end, jiffies)) {
		   	DRM_ERROR("space: %d wanted %d\n", ring->space, n);
		   	DRM_ERROR("lockup\n");
		   	goto out_wait_ring;
		}
		udelay(1);
	}

out_wait_ring:
   	return iters;
}

static void i810_kernel_lost_context(drm_device_t *dev)
{
      	drm_i810_private_t *dev_priv = dev->dev_private;
   	drm_i810_ring_buffer_t *ring = &(dev_priv->ring);

   	ring->head = I810_READ(LP_RING + RING_HEAD) & HEAD_ADDR;
     	ring->tail = I810_READ(LP_RING + RING_TAIL);
     	ring->space = ring->head - (ring->tail+8);
     	if (ring->space < 0) ring->space += ring->Size;
}

static int i810_freelist_init(drm_device_t *dev, drm_i810_private_t *dev_priv)
{
      	drm_device_dma_t *dma = dev->dma;
   	int my_idx = 24;
   	u32 *hw_status = (u32 *)(dev_priv->hw_status_page + my_idx);
   	int i;

	if (dma->buf_count > 1019) {
	   	/* Not enough space in the status page for the freelist */
	   	return -EINVAL;
	}

   	for (i = 0; i < dma->buf_count; i++) {
	   	drm_buf_t *buf = dma->buflist[ i ];
	   	drm_i810_buf_priv_t *buf_priv = buf->dev_private;

	   	buf_priv->in_use = hw_status++;
	   	buf_priv->my_use_idx = my_idx;
	   	my_idx += 4;

	   	*buf_priv->in_use = I810_BUF_FREE;

		buf_priv->kernel_virtual = drm_ioremap(buf->bus_address,
							buf->total, dev);
	}
	return 0;
}

static int i810_dma_initialize(drm_device_t *dev,
			       drm_i810_private_t *dev_priv,
			       drm_i810_init_t *init)
{
	struct list_head *list;

   	memset(dev_priv, 0, sizeof(drm_i810_private_t));

	list_for_each(list, &dev->maplist->head) {
		drm_map_list_t *r_list = list_entry(list, drm_map_list_t, head);
		if (r_list->map &&
		    r_list->map->type == _DRM_SHM &&
		    r_list->map->flags & _DRM_CONTAINS_LOCK ) {
			dev_priv->sarea_map = r_list->map;
 			break;
 		}
 	}
	if (!dev_priv->sarea_map) {
		dev->dev_private = (void *)dev_priv;
	   	i810_dma_cleanup(dev);
	   	DRM_ERROR("can not find sarea!\n");
	   	return -EINVAL;
	}
	dev_priv->mmio_map = drm_core_findmap(dev, init->mmio_offset);
	if (!dev_priv->mmio_map) {
		dev->dev_private = (void *)dev_priv;
	   	i810_dma_cleanup(dev);
	   	DRM_ERROR("can not find mmio map!\n");
	   	return -EINVAL;
	}
	dev->agp_buffer_map = drm_core_findmap(dev, init->buffers_offset);
	if (!dev->agp_buffer_map) {
		dev->dev_private = (void *)dev_priv;
	   	i810_dma_cleanup(dev);
	   	DRM_ERROR("can not find dma buffer map!\n");
	   	return -EINVAL;
	}

	dev_priv->sarea_priv = (drm_i810_sarea_t *)
		((u8 *)dev_priv->sarea_map->handle +
		 init->sarea_priv_offset);

   	dev_priv->ring.Start = init->ring_start;
   	dev_priv->ring.End = init->ring_end;
   	dev_priv->ring.Size = init->ring_size;

   	dev_priv->ring.virtual_start = drm_ioremap(dev->agp->base +
						    init->ring_start,
						    init->ring_size, dev);

   	if (dev_priv->ring.virtual_start == NULL) {
		dev->dev_private = (void *) dev_priv;
	   	i810_dma_cleanup(dev);
	   	DRM_ERROR("can not ioremap virtual address for"
			  " ring buffer\n");
	   	return -ENOMEM;
	}

   	dev_priv->ring.tail_mask = dev_priv->ring.Size - 1;

	dev_priv->w = init->w;
	dev_priv->h = init->h;
	dev_priv->pitch = init->pitch;
	dev_priv->back_offset = init->back_offset;
	dev_priv->depth_offset = init->depth_offset;
	dev_priv->front_offset = init->front_offset;

	dev_priv->overlay_offset = init->overlay_offset;
	dev_priv->overlay_physical = init->overlay_physical;

	dev_priv->front_di1 = init->front_offset | init->pitch_bits;
	dev_priv->back_di1 = init->back_offset | init->pitch_bits;
	dev_priv->zi1 = init->depth_offset | init->pitch_bits;

   	/* Program Hardware Status Page */
   	dev_priv->hw_status_page =
		pci_alloc_consistent(dev->pdev, PAGE_SIZE,
						&dev_priv->dma_status_page);
   	if (!dev_priv->hw_status_page) {
		dev->dev_private = (void *)dev_priv;
		i810_dma_cleanup(dev);
		DRM_ERROR("Can not allocate hardware status page\n");
		return -ENOMEM;
	}
   	memset(dev_priv->hw_status_page, 0, PAGE_SIZE);
   	DRM_DEBUG("hw status page @ %p\n", dev_priv->hw_status_page);

	I810_WRITE(0x02080, dev_priv->dma_status_page);
   	DRM_DEBUG("Enabled hardware status page\n");

   	/* Now we need to init our freelist */
	if (i810_freelist_init(dev, dev_priv) != 0) {
		dev->dev_private = (void *)dev_priv;
	   	i810_dma_cleanup(dev);
	   	DRM_ERROR("Not enough space in the status page for"
			  " the freelist\n");
	   	return -ENOMEM;
	}
	dev->dev_private = (void *)dev_priv;

   	return 0;
}

/* i810 DRM version 1.1 used a smaller init structure with different
 * ordering of values than is currently used (drm >= 1.2). There is
 * no defined way to detect the XFree version to correct this problem,
 * however by checking using this procedure we can detect the correct
 * thing to do.
 *
 * #1 Read the Smaller init structure from user-space
 * #2 Verify the overlay_physical is a valid physical address, or NULL
 *    If it isn't then we have a v1.1 client. Fix up params.
 *    If it is, then we have a 1.2 client... get the rest of the data.
 */
int i810_dma_init_compat(drm_i810_init_t *init, unsigned long arg)
{

	/* Get v1.1 init data */
	if (copy_from_user(init, (drm_i810_pre12_init_t __user *)arg,
			  sizeof(drm_i810_pre12_init_t))) {
		return -EFAULT;
	}

	if ((!init->overlay_physical) || (init->overlay_physical > 4096)) {

		/* This is a v1.2 client, just get the v1.2 init data */
		DRM_INFO("Using POST v1.2 init.\n");
		if (copy_from_user(init, (drm_i810_init_t __user *)arg,
				   sizeof(drm_i810_init_t))) {
			return -EFAULT;
		}
	} else {

		/* This is a v1.1 client, fix the params */
		DRM_INFO("Using PRE v1.2 init.\n");
	 	init->pitch_bits = init->h;
	 	init->pitch = init->w;
	 	init->h = init->overlay_physical;
	 	init->w = init->overlay_offset;
	 	init->overlay_physical = 0;
	 	init->overlay_offset = 0;
	}

	return 0;
}

int i810_dma_init(struct inode *inode, struct file *filp,
		  unsigned int cmd, unsigned long arg)
{
   	drm_file_t *priv = filp->private_data;
   	drm_device_t *dev = priv->dev;
   	drm_i810_private_t *dev_priv;
   	drm_i810_init_t init;
   	int retcode = 0;

	/* Get only the init func */
	if (copy_from_user(&init, (void __user *)arg, sizeof(drm_i810_init_func_t))) 
		return -EFAULT;

   	switch(init.func) {
	 	case I810_INIT_DMA:
	 	       	/* This case is for backward compatibility. It
			 * handles XFree 4.1.0 and 4.2.0, and has to
			 * do some parameter checking as described below.
			 * It will someday go away.
			 */
			retcode = i810_dma_init_compat(&init, arg);
			if (retcode)
				return retcode;

	   		dev_priv = drm_alloc(sizeof(drm_i810_private_t),
					     DRM_MEM_DRIVER);
	   		if (dev_priv == NULL)
				return -ENOMEM;
	   		retcode = i810_dma_initialize(dev, dev_priv, &init);
			break;

		default:
	 	case I810_INIT_DMA_1_4:
			DRM_INFO("Using v1.4 init.\n");
  			if (copy_from_user(&init, (drm_i810_init_t __user *)arg,
					  sizeof(drm_i810_init_t))) {
				return -EFAULT;
			}
	   		dev_priv = drm_alloc(sizeof(drm_i810_private_t),
					     DRM_MEM_DRIVER);
			if (dev_priv == NULL) 
				return -ENOMEM;
	   		retcode = i810_dma_initialize(dev, dev_priv, &init);
			break;

	 	case I810_CLEANUP_DMA:
		        DRM_INFO("DMA Cleanup\n");
	   		retcode = i810_dma_cleanup(dev);
              	   	break;
	}

   	return retcode;
}



/* Most efficient way to verify state for the i810 is as it is
 * emitted.  Non-conformant state is silently dropped.
 *
 * Use 'volatile' & local var tmp to force the emitted values to be
 * identical to the verified ones.
 */
static void i810EmitContextVerified( drm_device_t *dev,
				     volatile unsigned int *code )
{
   	drm_i810_private_t *dev_priv = dev->dev_private;
	int i, j = 0;
	unsigned int tmp;
	RING_LOCALS;

	BEGIN_LP_RING( I810_CTX_SETUP_SIZE );

	OUT_RING( GFX_OP_COLOR_FACTOR );
	OUT_RING( code[I810_CTXREG_CF1] );

	OUT_RING( GFX_OP_STIPPLE );
	OUT_RING( code[I810_CTXREG_ST1] );

	for ( i = 4 ; i < I810_CTX_SETUP_SIZE ; i++ ) {
		tmp = code[i];

		if ((tmp & (7<<29)) == (3<<29) &&
		    (tmp & (0x1f<<24)) < (0x1d<<24))
		{
			OUT_RING( tmp );
			j++;
		}
		else printk("constext state dropped!!!\n");
	}

	if (j & 1)
		OUT_RING( 0 );

	ADVANCE_LP_RING();
}

static void i810EmitTexVerified( drm_device_t *dev,
				 volatile unsigned int *code )
{
   	drm_i810_private_t *dev_priv = dev->dev_private;
	int i, j = 0;
	unsigned int tmp;
	RING_LOCALS;

	BEGIN_LP_RING( I810_TEX_SETUP_SIZE );

	OUT_RING( GFX_OP_MAP_INFO );
	OUT_RING( code[I810_TEXREG_MI1] );
	OUT_RING( code[I810_TEXREG_MI2] );
	OUT_RING( code[I810_TEXREG_MI3] );

	for ( i = 4 ; i < I810_TEX_SETUP_SIZE ; i++ ) {
		tmp = code[i];

		if ((tmp & (7<<29)) == (3<<29) &&
		    (tmp & (0x1f<<24)) < (0x1d<<24))
		{
			OUT_RING( tmp );
			j++;
		}
		else printk("texture state dropped!!!\n");
	}

	if (j & 1)
		OUT_RING( 0 );

	ADVANCE_LP_RING();
}


/* Need to do some additional checking when setting the dest buffer.
 */
static void i810EmitDestVerified( drm_device_t *dev,
				  volatile unsigned int *code )
{
   	drm_i810_private_t *dev_priv = dev->dev_private;
	unsigned int tmp;
	RING_LOCALS;

	BEGIN_LP_RING( I810_DEST_SETUP_SIZE + 2 );

	tmp = code[I810_DESTREG_DI1];
	if (tmp == dev_priv->front_di1 || tmp == dev_priv->back_di1) {
		OUT_RING( CMD_OP_DESTBUFFER_INFO );
		OUT_RING( tmp );
	} else
	   DRM_DEBUG("bad di1 %x (allow %x or %x)\n",
		     tmp, dev_priv->front_di1, dev_priv->back_di1);

	/* invarient:
	 */
	OUT_RING( CMD_OP_Z_BUFFER_INFO );
	OUT_RING( dev_priv->zi1 );

	OUT_RING( GFX_OP_DESTBUFFER_VARS );
	OUT_RING( code[I810_DESTREG_DV1] );

	OUT_RING( GFX_OP_DRAWRECT_INFO );
	OUT_RING( code[I810_DESTREG_DR1] );
	OUT_RING( code[I810_DESTREG_DR2] );
	OUT_RING( code[I810_DESTREG_DR3] );
	OUT_RING( code[I810_DESTREG_DR4] );
	OUT_RING( 0 );

	ADVANCE_LP_RING();
}



static void i810EmitState( drm_device_t *dev )
{
   	drm_i810_private_t *dev_priv = dev->dev_private;
      	drm_i810_sarea_t *sarea_priv = dev_priv->sarea_priv;
	unsigned int dirty = sarea_priv->dirty;
	
	DRM_DEBUG("%s %x\n", __FUNCTION__, dirty);

	if (dirty & I810_UPLOAD_BUFFERS) {
		i810EmitDestVerified( dev, sarea_priv->BufferState );
		sarea_priv->dirty &= ~I810_UPLOAD_BUFFERS;
	}

	if (dirty & I810_UPLOAD_CTX) {
		i810EmitContextVerified( dev, sarea_priv->ContextState );
		sarea_priv->dirty &= ~I810_UPLOAD_CTX;
	}

	if (dirty & I810_UPLOAD_TEX0) {
		i810EmitTexVerified( dev, sarea_priv->TexState[0] );
		sarea_priv->dirty &= ~I810_UPLOAD_TEX0;
	}

	if (dirty & I810_UPLOAD_TEX1) {
		i810EmitTexVerified( dev, sarea_priv->TexState[1] );
		sarea_priv->dirty &= ~I810_UPLOAD_TEX1;
	}
}



/* need to verify
 */
static void i810_dma_dispatch_clear( drm_device_t *dev, int flags,
				     unsigned int clear_color,
				     unsigned int clear_zval )
{
   	drm_i810_private_t *dev_priv = dev->dev_private;
      	drm_i810_sarea_t *sarea_priv = dev_priv->sarea_priv;
	int nbox = sarea_priv->nbox;
	drm_clip_rect_t *pbox = sarea_priv->boxes;
	int pitch = dev_priv->pitch;
	int cpp = 2;
	int i;
	RING_LOCALS;
	
	if ( dev_priv->current_page == 1 ) {
	        unsigned int tmp = flags;
	       
		flags &= ~(I810_FRONT | I810_BACK);
		if (tmp & I810_FRONT) flags |= I810_BACK;
		if (tmp & I810_BACK) flags |= I810_FRONT;
	}

  	i810_kernel_lost_context(dev);

      	if (nbox > I810_NR_SAREA_CLIPRECTS)
     		nbox = I810_NR_SAREA_CLIPRECTS;

	for (i = 0 ; i < nbox ; i++, pbox++) {
		unsigned int x = pbox->x1;
		unsigned int y = pbox->y1;
		unsigned int width = (pbox->x2 - x) * cpp;
		unsigned int height = pbox->y2 - y;
		unsigned int start = y * pitch + x * cpp;

		if (pbox->x1 > pbox->x2 ||
		    pbox->y1 > pbox->y2 ||
		    pbox->x2 > dev_priv->w ||
		    pbox->y2 > dev_priv->h)
			continue;

	   	if ( flags & I810_FRONT ) {
			BEGIN_LP_RING( 6 );
			OUT_RING( BR00_BITBLT_CLIENT |
				  BR00_OP_COLOR_BLT | 0x3 );
			OUT_RING( BR13_SOLID_PATTERN | (0xF0 << 16) | pitch );
			OUT_RING( (height << 16) | width );
			OUT_RING( start );
			OUT_RING( clear_color );
			OUT_RING( 0 );
			ADVANCE_LP_RING();
		}

		if ( flags & I810_BACK ) {
			BEGIN_LP_RING( 6 );
			OUT_RING( BR00_BITBLT_CLIENT |
				  BR00_OP_COLOR_BLT | 0x3 );
			OUT_RING( BR13_SOLID_PATTERN | (0xF0 << 16) | pitch );
			OUT_RING( (height << 16) | width );
			OUT_RING( dev_priv->back_offset + start );
			OUT_RING( clear_color );
			OUT_RING( 0 );
			ADVANCE_LP_RING();
		}

		if ( flags & I810_DEPTH ) {
			BEGIN_LP_RING( 6 );
			OUT_RING( BR00_BITBLT_CLIENT |
				  BR00_OP_COLOR_BLT | 0x3 );
			OUT_RING( BR13_SOLID_PATTERN | (0xF0 << 16) | pitch );
			OUT_RING( (height << 16) | width );
			OUT_RING( dev_priv->depth_offset + start );
			OUT_RING( clear_zval );
			OUT_RING( 0 );
			ADVANCE_LP_RING();
		}
	}
}

static void i810_dma_dispatch_swap( drm_device_t *dev )
{
   	drm_i810_private_t *dev_priv = dev->dev_private;
      	drm_i810_sarea_t *sarea_priv = dev_priv->sarea_priv;
	int nbox = sarea_priv->nbox;
	drm_clip_rect_t *pbox = sarea_priv->boxes;
	int pitch = dev_priv->pitch;
	int cpp = 2;
	int i;
	RING_LOCALS;

	DRM_DEBUG("swapbuffers\n");

  	i810_kernel_lost_context(dev);

      	if (nbox > I810_NR_SAREA_CLIPRECTS)
     		nbox = I810_NR_SAREA_CLIPRECTS;

	for (i = 0 ; i < nbox; i++, pbox++)
	{
		unsigned int w = pbox->x2 - pbox->x1;
		unsigned int h = pbox->y2 - pbox->y1;
		unsigned int dst = pbox->x1*cpp + pbox->y1*pitch;
		unsigned int start = dst;

		if (pbox->x1 > pbox->x2 ||
		    pbox->y1 > pbox->y2 ||
		    pbox->x2 > dev_priv->w ||
		    pbox->y2 > dev_priv->h)
			continue;

		BEGIN_LP_RING( 6 );
		OUT_RING( BR00_BITBLT_CLIENT | BR00_OP_SRC_COPY_BLT | 0x4 );
		OUT_RING( pitch | (0xCC << 16));
		OUT_RING( (h << 16) | (w * cpp));
		if (dev_priv->current_page == 0)
		  OUT_RING(dev_priv->front_offset + start);
		else
		  OUT_RING(dev_priv->back_offset + start);
		OUT_RING( pitch );
		if (dev_priv->current_page == 0)
		  OUT_RING(dev_priv->back_offset + start);
		else
		  OUT_RING(dev_priv->front_offset + start);
		ADVANCE_LP_RING();
	}
}


static void i810_dma_dispatch_vertex(drm_device_t *dev,
				     drm_buf_t *buf,
				     int discard,
				     int used)
{
   	drm_i810_private_t *dev_priv = dev->dev_private;
	drm_i810_buf_priv_t *buf_priv = buf->dev_private;
   	drm_i810_sarea_t *sarea_priv = dev_priv->sarea_priv;
   	drm_clip_rect_t *box = sarea_priv->boxes;
   	int nbox = sarea_priv->nbox;
	unsigned long address = (unsigned long)buf->bus_address;
	unsigned long start = address - dev->agp->base;
	int i = 0;
   	RING_LOCALS;

   	i810_kernel_lost_context(dev);

   	if (nbox > I810_NR_SAREA_CLIPRECTS)
		nbox = I810_NR_SAREA_CLIPRECTS;

	if (used > 4*1024)
		used = 0;

	if (sarea_priv->dirty)
	   i810EmitState( dev );

	if (buf_priv->currently_mapped == I810_BUF_MAPPED) {
		unsigned int prim = (sarea_priv->vertex_prim & PR_MASK);

		*(u32 *)buf_priv->kernel_virtual = ((GFX_OP_PRIMITIVE | prim | ((used/4)-2)));

		if (used & 4) {
			*(u32 *)((u32)buf_priv->kernel_virtual + used) = 0;
			used += 4;
		}

		i810_unmap_buffer(buf);
	}

	if (used) {
		do {
			if (i < nbox) {
				BEGIN_LP_RING(4);
				OUT_RING( GFX_OP_SCISSOR | SC_UPDATE_SCISSOR |
					  SC_ENABLE );
				OUT_RING( GFX_OP_SCISSOR_INFO );
				OUT_RING( box[i].x1 | (box[i].y1<<16) );
				OUT_RING( (box[i].x2-1) | ((box[i].y2-1)<<16) );
				ADVANCE_LP_RING();
			}

			BEGIN_LP_RING(4);
			OUT_RING( CMD_OP_BATCH_BUFFER );
			OUT_RING( start | BB1_PROTECTED );
			OUT_RING( start + used - 4 );
			OUT_RING( 0 );
			ADVANCE_LP_RING();

		} while (++i < nbox);
	}

	if (discard) {
		dev_priv->counter++;

		(void) cmpxchg(buf_priv->in_use, I810_BUF_CLIENT,
			       I810_BUF_HARDWARE);

		BEGIN_LP_RING(8);
		OUT_RING( CMD_STORE_DWORD_IDX );
		OUT_RING( 20 );
		OUT_RING( dev_priv->counter );
		OUT_RING( CMD_STORE_DWORD_IDX );
		OUT_RING( buf_priv->my_use_idx );
		OUT_RING( I810_BUF_FREE );
		OUT_RING( CMD_REPORT_HEAD );
		OUT_RING( 0 );
		ADVANCE_LP_RING();
	}
}

static void i810_dma_dispatch_flip( drm_device_t *dev )
{
        drm_i810_private_t *dev_priv = dev->dev_private;
	int pitch = dev_priv->pitch;
	RING_LOCALS;

	DRM_DEBUG( "%s: page=%d pfCurrentPage=%d\n", 
		__FUNCTION__, 
		dev_priv->current_page,
		dev_priv->sarea_priv->pf_current_page);
	
        i810_kernel_lost_context(dev);

	BEGIN_LP_RING( 2 );
   	OUT_RING( INST_PARSER_CLIENT | INST_OP_FLUSH | INST_FLUSH_MAP_CACHE ); 
	OUT_RING( 0 );
	ADVANCE_LP_RING();

	BEGIN_LP_RING( I810_DEST_SETUP_SIZE + 2 );
	/* On i815 at least ASYNC is buggy */
	/* pitch<<5 is from 11.2.8 p158,
	   its the pitch / 8 then left shifted 8,
	   so (pitch >> 3) << 8 */
	OUT_RING( CMD_OP_FRONTBUFFER_INFO | (pitch<<5) /*| ASYNC_FLIP */ );
	if ( dev_priv->current_page == 0 ) {
		OUT_RING( dev_priv->back_offset );
		dev_priv->current_page = 1;
	} else {
		OUT_RING( dev_priv->front_offset );
		dev_priv->current_page = 0;
	}
	OUT_RING(0);
	ADVANCE_LP_RING();

	BEGIN_LP_RING(2);
	OUT_RING( CMD_OP_WAIT_FOR_EVENT | WAIT_FOR_PLANE_A_FLIP );
	OUT_RING( 0 );
	ADVANCE_LP_RING();

	/* Increment the frame counter.  The client-side 3D driver must
	 * throttle the framerate by waiting for this value before
	 * performing the swapbuffer ioctl.
	 */
	dev_priv->sarea_priv->pf_current_page = dev_priv->current_page;

}

void i810_dma_quiescent(drm_device_t *dev)
{
      	drm_i810_private_t *dev_priv = dev->dev_private;
   	RING_LOCALS;

/*  	printk("%s\n", __FUNCTION__); */

  	i810_kernel_lost_context(dev);

   	BEGIN_LP_RING(4);
   	OUT_RING( INST_PARSER_CLIENT | INST_OP_FLUSH | INST_FLUSH_MAP_CACHE );
   	OUT_RING( CMD_REPORT_HEAD );
      	OUT_RING( 0 );
      	OUT_RING( 0 );
   	ADVANCE_LP_RING();

	i810_wait_ring( dev, dev_priv->ring.Size - 8 );
}

static int i810_flush_queue(drm_device_t *dev)
{
   	drm_i810_private_t *dev_priv = dev->dev_private;
	drm_device_dma_t *dma = dev->dma;
   	int i, ret = 0;
   	RING_LOCALS;
	
/*  	printk("%s\n", __FUNCTION__); */

   	i810_kernel_lost_context(dev);

   	BEGIN_LP_RING(2);
      	OUT_RING( CMD_REPORT_HEAD );
      	OUT_RING( 0 );
      	ADVANCE_LP_RING();

	i810_wait_ring( dev, dev_priv->ring.Size - 8 );

   	for (i = 0; i < dma->buf_count; i++) {
	   	drm_buf_t *buf = dma->buflist[ i ];
	   	drm_i810_buf_priv_t *buf_priv = buf->dev_private;

		int used = cmpxchg(buf_priv->in_use, I810_BUF_HARDWARE,
				   I810_BUF_FREE);

		if (used == I810_BUF_HARDWARE)
			DRM_DEBUG("reclaimed from HARDWARE\n");
		if (used == I810_BUF_CLIENT)
			DRM_DEBUG("still on client\n");
	}

   	return ret;
}

/* Must be called with the lock held */
void i810_reclaim_buffers(struct file *filp)
{
	drm_file_t    *priv   = filp->private_data;
	drm_device_t  *dev    = priv->dev;
	drm_device_dma_t *dma = dev->dma;
	int		 i;

	if (!dma) return;
      	if (!dev->dev_private) return;
	if (!dma->buflist) return;

        i810_flush_queue(dev);

	for (i = 0; i < dma->buf_count; i++) {
	   	drm_buf_t *buf = dma->buflist[ i ];
	   	drm_i810_buf_priv_t *buf_priv = buf->dev_private;

		if (buf->filp == filp && buf_priv) {
			int used = cmpxchg(buf_priv->in_use, I810_BUF_CLIENT,
					   I810_BUF_FREE);

			if (used == I810_BUF_CLIENT)
				DRM_DEBUG("reclaimed from client\n");
			if (buf_priv->currently_mapped == I810_BUF_MAPPED)
		     		buf_priv->currently_mapped = I810_BUF_UNMAPPED;
		}
	}
}

int i810_flush_ioctl(struct inode *inode, struct file *filp,
		     unsigned int cmd, unsigned long arg)
{
   	drm_file_t	  *priv	  = filp->private_data;
   	drm_device_t	  *dev	  = priv->dev;

	if (!_DRM_LOCK_IS_HELD(dev->lock.hw_lock->lock)) {
		DRM_ERROR("i810_flush_ioctl called without lock held\n");
		return -EINVAL;
	}

   	i810_flush_queue(dev);
   	return 0;
}


int i810_dma_vertex(struct inode *inode, struct file *filp,
	       unsigned int cmd, unsigned long arg)
{
	drm_file_t *priv = filp->private_data;
	drm_device_t *dev = priv->dev;
	drm_device_dma_t *dma = dev->dma;
   	drm_i810_private_t *dev_priv = (drm_i810_private_t *)dev->dev_private;
      	u32 *hw_status = dev_priv->hw_status_page;
   	drm_i810_sarea_t *sarea_priv = (drm_i810_sarea_t *)
     					dev_priv->sarea_priv;
	drm_i810_vertex_t vertex;

	if (copy_from_user(&vertex, (drm_i810_vertex_t __user *)arg, sizeof(vertex)))
		return -EFAULT;

	if (!_DRM_LOCK_IS_HELD(dev->lock.hw_lock->lock)) {
		DRM_ERROR("i810_dma_vertex called without lock held\n");
		return -EINVAL;
	}

	DRM_DEBUG("i810 dma vertex, idx %d used %d discard %d\n",
		  vertex.idx, vertex.used, vertex.discard);

	if (vertex.idx < 0 || vertex.idx > dma->buf_count) 
		return -EINVAL;

	i810_dma_dispatch_vertex( dev,
				  dma->buflist[ vertex.idx ],
				  vertex.discard, vertex.used );

   	atomic_add(vertex.used, &dev->counts[_DRM_STAT_SECONDARY]);
	atomic_inc(&dev->counts[_DRM_STAT_DMA]);
	sarea_priv->last_enqueue = dev_priv->counter-1;
   	sarea_priv->last_dispatch = (int) hw_status[5];

	return 0;
}



int i810_clear_bufs(struct inode *inode, struct file *filp,
		   unsigned int cmd, unsigned long arg)
{
	drm_file_t *priv = filp->private_data;
	drm_device_t *dev = priv->dev;
	drm_i810_clear_t clear;

   	if (copy_from_user(&clear, (drm_i810_clear_t __user *)arg, sizeof(clear)))
		return -EFAULT;

	if (!_DRM_LOCK_IS_HELD(dev->lock.hw_lock->lock)) {
		DRM_ERROR("i810_clear_bufs called without lock held\n");
		return -EINVAL;
	}

 	/* GH: Someone's doing nasty things... */
 	if (!dev->dev_private) {
 		return -EINVAL;
 	}

	i810_dma_dispatch_clear( dev, clear.flags,
				 clear.clear_color,
				 clear.clear_depth );
   	return 0;
}

int i810_swap_bufs(struct inode *inode, struct file *filp,
		  unsigned int cmd, unsigned long arg)
{
	drm_file_t *priv = filp->private_data;
	drm_device_t *dev = priv->dev;

	DRM_DEBUG("i810_swap_bufs\n");

	if (!_DRM_LOCK_IS_HELD(dev->lock.hw_lock->lock)) {
		DRM_ERROR("i810_swap_buf called without lock held\n");
		return -EINVAL;
	}

	i810_dma_dispatch_swap( dev );
   	return 0;
}

int i810_getage(struct inode *inode, struct file *filp, unsigned int cmd,
		unsigned long arg)
{
   	drm_file_t	  *priv	    = filp->private_data;
	drm_device_t	  *dev	    = priv->dev;
   	drm_i810_private_t *dev_priv = (drm_i810_private_t *)dev->dev_private;
      	u32 *hw_status = dev_priv->hw_status_page;
   	drm_i810_sarea_t *sarea_priv = (drm_i810_sarea_t *)
     					dev_priv->sarea_priv;

      	sarea_priv->last_dispatch = (int) hw_status[5];
	return 0;
}

int i810_getbuf(struct inode *inode, struct file *filp, unsigned int cmd,
		unsigned long arg)
{
	drm_file_t	  *priv	    = filp->private_data;
	drm_device_t	  *dev	    = priv->dev;
	int		  retcode   = 0;
	drm_i810_dma_t	  d;
   	drm_i810_private_t *dev_priv = (drm_i810_private_t *)dev->dev_private;
   	u32 *hw_status = dev_priv->hw_status_page;
   	drm_i810_sarea_t *sarea_priv = (drm_i810_sarea_t *)
     					dev_priv->sarea_priv;

   	if (copy_from_user(&d, (drm_i810_dma_t __user *)arg, sizeof(d)))
		return -EFAULT;

	if (!_DRM_LOCK_IS_HELD(dev->lock.hw_lock->lock)) {
		DRM_ERROR("i810_dma called without lock held\n");
		return -EINVAL;
	}

	d.granted = 0;

	retcode = i810_dma_get_buffer(dev, &d, filp);

	DRM_DEBUG("i810_dma: %d returning %d, granted = %d\n",
		  current->pid, retcode, d.granted);

	if (copy_to_user((drm_dma_t __user *)arg, &d, sizeof(d)))
		return -EFAULT;
   	sarea_priv->last_dispatch = (int) hw_status[5];

	return retcode;
}

int i810_copybuf(struct inode *inode,
		 struct file *filp, 
		 unsigned int cmd,
		 unsigned long arg)
{
	/* Never copy - 2.4.x doesn't need it */
	return 0;
}

int i810_docopy(struct inode *inode, struct file *filp, unsigned int cmd,
		unsigned long arg)
{
	/* Never copy - 2.4.x doesn't need it */
	return 0;
}

static void i810_dma_dispatch_mc(drm_device_t *dev, drm_buf_t *buf, int used,
		unsigned int last_render)
{
	drm_i810_private_t *dev_priv = dev->dev_private;
	drm_i810_buf_priv_t *buf_priv = buf->dev_private;
	drm_i810_sarea_t *sarea_priv = dev_priv->sarea_priv;
	unsigned long address = (unsigned long)buf->bus_address;
	unsigned long start = address - dev->agp->base;
	int u;
	RING_LOCALS;

	i810_kernel_lost_context(dev);

	u = cmpxchg(buf_priv->in_use, I810_BUF_CLIENT,
		I810_BUF_HARDWARE);
	if (u != I810_BUF_CLIENT) {
		DRM_DEBUG("MC found buffer that isn't mine!\n");
	}

	if (used > 4*1024)
		used = 0;

	sarea_priv->dirty = 0x7f;

	DRM_DEBUG("dispatch mc addr 0x%lx, used 0x%x\n",
		address, used);

	dev_priv->counter++;
	DRM_DEBUG("dispatch counter : %ld\n", dev_priv->counter);
	DRM_DEBUG("i810_dma_dispatch_mc\n");
	DRM_DEBUG("start : %lx\n", start);
	DRM_DEBUG("used : %d\n", used);
	DRM_DEBUG("start + used - 4 : %ld\n", start + used - 4);

	if (buf_priv->currently_mapped == I810_BUF_MAPPED) {
		if (used & 4) {
			*(u32 *)((u32)buf_priv->virtual + used) = 0;
			used += 4;
		}

		i810_unmap_buffer(buf);
	}
	BEGIN_LP_RING(4);
	OUT_RING( CMD_OP_BATCH_BUFFER );
	OUT_RING( start | BB1_PROTECTED );
	OUT_RING( start + used - 4 );
	OUT_RING( 0 );
	ADVANCE_LP_RING();


	BEGIN_LP_RING(8);
	OUT_RING( CMD_STORE_DWORD_IDX );
	OUT_RING( buf_priv->my_use_idx );
	OUT_RING( I810_BUF_FREE );
	OUT_RING( 0 );

	OUT_RING( CMD_STORE_DWORD_IDX );
	OUT_RING( 16 );
	OUT_RING( last_render );
	OUT_RING( 0 );
	ADVANCE_LP_RING();
}

int i810_dma_mc(struct inode *inode, struct file *filp,
	unsigned int cmd, unsigned long arg)
{
	drm_file_t *priv = filp->private_data;
	drm_device_t *dev = priv->dev;
	drm_device_dma_t *dma = dev->dma;
	drm_i810_private_t *dev_priv = (drm_i810_private_t *)dev->dev_private;
	u32 *hw_status = dev_priv->hw_status_page;
	drm_i810_sarea_t *sarea_priv = (drm_i810_sarea_t *)
		dev_priv->sarea_priv;
	drm_i810_mc_t mc;

	if (copy_from_user(&mc, (drm_i810_mc_t __user *)arg, sizeof(mc)))
		return -EFAULT;

	if (!_DRM_LOCK_IS_HELD(dev->lock.hw_lock->lock)) {
		DRM_ERROR("i810_dma_mc called without lock held\n");
		return -EINVAL;
	}

	if (mc.idx >= dma->buf_count || mc.idx < 0)
		return -EINVAL;

	i810_dma_dispatch_mc(dev, dma->buflist[mc.idx], mc.used,
		mc.last_render );

	atomic_add(mc.used, &dev->counts[_DRM_STAT_SECONDARY]);
	atomic_inc(&dev->counts[_DRM_STAT_DMA]);
	sarea_priv->last_enqueue = dev_priv->counter-1;
	sarea_priv->last_dispatch = (int) hw_status[5];

	return 0;
}

int i810_rstatus(struct inode *inode, struct file *filp,
		unsigned int cmd, unsigned long arg)
{
	drm_file_t *priv = filp->private_data;
	drm_device_t *dev = priv->dev;
	drm_i810_private_t *dev_priv = (drm_i810_private_t *)dev->dev_private;

	return (int)(((u32 *)(dev_priv->hw_status_page))[4]);
}

int i810_ov0_info(struct inode *inode, struct file *filp,
		unsigned int cmd, unsigned long arg)
{
	drm_file_t *priv = filp->private_data;
	drm_device_t *dev = priv->dev;
	drm_i810_private_t *dev_priv = (drm_i810_private_t *)dev->dev_private;
	drm_i810_overlay_t data;

	data.offset = dev_priv->overlay_offset;
	data.physical = dev_priv->overlay_physical;
	if (copy_to_user((drm_i810_overlay_t __user *)arg,&data,sizeof(data)))
		return -EFAULT;
	return 0;
}

int i810_fstatus(struct inode *inode, struct file *filp,
		unsigned int cmd, unsigned long arg)
{
	drm_file_t *priv = filp->private_data;
	drm_device_t *dev = priv->dev;
	drm_i810_private_t *dev_priv = (drm_i810_private_t *)dev->dev_private;

	if (!_DRM_LOCK_IS_HELD(dev->lock.hw_lock->lock)) {
		DRM_ERROR("i810_fstatus called without lock held\n");
		return -EINVAL;
	}
	return I810_READ(0x30008);
}

int i810_ov0_flip(struct inode *inode, struct file *filp,
		unsigned int cmd, unsigned long arg)
{
	drm_file_t *priv = filp->private_data;
	drm_device_t *dev = priv->dev;
	drm_i810_private_t *dev_priv = (drm_i810_private_t *)dev->dev_private;

	if (!_DRM_LOCK_IS_HELD(dev->lock.hw_lock->lock)) {
		DRM_ERROR("i810_ov0_flip called without lock held\n");
		return -EINVAL;
	}

	//Tell the overlay to update
	I810_WRITE(0x30000,dev_priv->overlay_physical | 0x80000000);

	return 0;
}


/* Not sure why this isn't set all the time:
 */ 
static void i810_do_init_pageflip( drm_device_t *dev )
{
	drm_i810_private_t *dev_priv = dev->dev_private;
	
	DRM_DEBUG("%s\n", __FUNCTION__);
	dev_priv->page_flipping = 1;
	dev_priv->current_page = 0;
	dev_priv->sarea_priv->pf_current_page = dev_priv->current_page;
}

int i810_do_cleanup_pageflip( drm_device_t *dev )
{
	drm_i810_private_t *dev_priv = dev->dev_private;

	DRM_DEBUG("%s\n", __FUNCTION__);
	if (dev_priv->current_page != 0)
		i810_dma_dispatch_flip( dev );

	dev_priv->page_flipping = 0;
	return 0;
}

int i810_flip_bufs(struct inode *inode, struct file *filp,
		   unsigned int cmd, unsigned long arg)
{
	drm_file_t *priv = filp->private_data;
	drm_device_t *dev = priv->dev;
	drm_i810_private_t *dev_priv = dev->dev_private;

	DRM_DEBUG("%s\n", __FUNCTION__);

	if (!_DRM_LOCK_IS_HELD(dev->lock.hw_lock->lock)) {
		DRM_ERROR("i810_flip_buf called without lock held\n");
		return -EINVAL;
	}

	if (!dev_priv->page_flipping) 
		i810_do_init_pageflip( dev );

	i810_dma_dispatch_flip( dev );
   	return 0;
}

void i810_driver_pretakedown(drm_device_t *dev)
{
	i810_dma_cleanup( dev );
}

void i810_driver_release(drm_device_t *dev, struct file *filp)
{
	i810_reclaim_buffers(filp);
}

int i810_driver_dma_quiescent(drm_device_t *dev)
{
	i810_dma_quiescent( dev );
	return 0;
}