/* i915_dma.c -- DMA support for the I915 -*- linux-c -*-
*/
/*
* Copyright 2003 Tungsten Graphics, Inc., Cedar Park, Texas.
* 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, sub license, 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 NON-INFRINGEMENT.
* IN NO EVENT SHALL TUNGSTEN GRAPHICS 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.
*
*/
#include "drmP.h"
#include "drm.h"
#include "drm_crtc_helper.h"
#include "intel_drv.h"
#include "i915_drm.h"
#include "i915_drv.h"
/* Really want an OS-independent resettable timer. Would like to have
* this loop run for (eg) 3 sec, but have the timer reset every time
* the head pointer changes, so that EBUSY only happens if the ring
* actually stalls for (eg) 3 seconds.
*/
int i915_wait_ring(struct drm_device * dev, int n, const char *caller)
{
drm_i915_private_t *dev_priv = dev->dev_private;
struct drm_i915_master_private *master_priv = dev->primary->master->driver_priv;
drm_i915_ring_buffer_t *ring = &(dev_priv->ring);
u32 acthd_reg = IS_I965G(dev) ? ACTHD_I965 : ACTHD;
u32 last_acthd = I915_READ(acthd_reg);
u32 acthd;
u32 last_head = I915_READ(PRB0_HEAD) & HEAD_ADDR;
int i;
for (i = 0; i < 100000; i++) {
ring->head = I915_READ(PRB0_HEAD) & HEAD_ADDR;
acthd = I915_READ(acthd_reg);
ring->space = ring->head - (ring->tail + 8);
if (ring->space < 0)
ring->space += ring->Size;
if (ring->space >= n)
return 0;
if (master_priv->sarea_priv)
master_priv->sarea_priv->perf_boxes |= I915_BOX_WAIT;
if (ring->head != last_head)
i = 0;
if (acthd != last_acthd)
i =