src/mesa/drivers/dri/intel/intel_mipmap_tree.c - fp2-dev/platform/external/mesa3d - Gitiles

 /**************************************************************************
  *
  * Copyright 2006 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 "intel_context.h"
 #include "intel_mipmap_tree.h"
 #include "intel_regions.h"
 #include "intel_tex_layout.h"
 #include "intel_chipset.h"
 #ifndef I915
 #include "brw_state.h"
 #endif
 #include "main/enums.h"

 #define FILE_DEBUG_FLAG DEBUG_MIPTREE


 static GLenum
 target_to_target(GLenum target)
 {
    switch (target) {
    case GL_TEXTURE_CUBE_MAP_POSITIVE_X_ARB:
    case GL_TEXTURE_CUBE_MAP_NEGATIVE_X_ARB:
    case GL_TEXTURE_CUBE_MAP_POSITIVE_Y_ARB:
    case GL_TEXTURE_CUBE_MAP_NEGATIVE_Y_ARB:
    case GL_TEXTURE_CUBE_MAP_POSITIVE_Z_ARB:
    case GL_TEXTURE_CUBE_MAP_NEGATIVE_Z_ARB:
       return GL_TEXTURE_CUBE_MAP_ARB;
    default:
       return target;
    }
 }


 static struct intel_mipmap_tree *
 intel_miptree_create_internal(struct intel_context *intel,
 			      GLenum target,
 			      GLenum internal_format,
 			      GLuint first_level,
 			      GLuint last_level,
 			      GLuint width0,
 			      GLuint height0,
 			      GLuint depth0, GLuint cpp, GLuint compress_byte,
 			      uint32_t tiling)
 {
    GLboolean ok;
    struct intel_mipmap_tree *mt = calloc(sizeof(*mt), 1);

    DBG("%s target %s format %s level %d..%d <-- %p\n", __FUNCTION__,
        _mesa_lookup_enum_by_nr(target),
        _mesa_lookup_enum_by_nr(internal_format),
        first_level, last_level, mt);

    mt->target = target_to_target(target);
    mt->internal_format = internal_format;
    mt->first_level = first_level;
    mt->last_level = last_level;
    mt->width0 = width0;
    mt->height0 = height0;
    mt->depth0 = depth0;
    mt->cpp = compress_byte ? compress_byte : cpp;
    mt->compressed = compress_byte ? 1 : 0;
    mt->refcount = 1;
    mt->pitch = 0;

 #ifdef I915
    if (intel->is_945)
       ok = i945_miptree_layout(intel, mt, tiling);
    else
       ok = i915_miptree_layout(intel, mt, tiling);
 #else
    ok = brw_miptree_layout(intel, mt, tiling);
 #endif

    if (!ok) {
       free(mt);
       DBG("%s not okay - returning NULL\n", __FUNCTION__);
       return NULL;
    }

    return mt;
 }


 struct intel_mipmap_tree *
 intel_miptree_create(struct intel_context *intel,
 		     GLenum target,
 		     GLenum base_format,
 		     GLenum internal_format,
 		     GLuint first_level,
 		     GLuint last_level,
 		     GLuint width0,
 		     GLuint height0,
 		     GLuint depth0, GLuint cpp, GLuint compress_byte,
 		     GLboolean expect_accelerated_upload)
 {
    struct intel_mipmap_tree *mt;
    uint32_t tiling;

    if (intel->use_texture_tiling && compress_byte == 0 &&
        intel->intelScreen->kernel_exec_fencing) {
       if (intel->gen >= 4 &&
 	  (base_format == GL_DEPTH_COMPONENT ||
 	   base_format == GL_DEPTH_STENCIL_EXT))
 	 tiling = I915_TILING_Y;
       else
 	 tiling = I915_TILING_X;
    } else
       tiling = I915_TILING_NONE;

    mt = intel_miptree_create_internal(intel, target, internal_format,
 				      first_level, last_level, width0,
 				      height0, depth0, cpp, compress_byte,
 				      tiling);
    /*
     * pitch == 0 || height == 0  indicates the null texture
     */
    if (!mt || !mt->pitch || !mt->total_height) {
       free(mt);
       return NULL;
    }

    mt->region = intel_region_alloc(intel,
 				   tiling,
 				   mt->cpp,
 				   mt->pitch,
 				   mt->total_height,
 				   mt->pitch,
 				   expect_accelerated_upload);

    if (!mt->region) {
        free(mt);
        return NULL;
    }

    return mt;
 }


 struct intel_mipmap_tree *
 intel_miptree_create_for_region(struct intel_context *intel,
 				GLenum target,
 				GLenum internal_format,
 				GLuint first_level,
 				GLuint last_level,
 				struct intel_region *region,
 				GLuint depth0,
 				GLuint compress_byte)
 {
    struct intel_mipmap_tree *mt;

    mt = intel_miptree_create_internal(intel, target, internal_format,
 				      first_level, last_level,
 				      region->width, region->height, 1,
 				      region->cpp, compress_byte,
 				      I915_TILING_NONE);
    if (!mt)
       return mt;
 #if 0
    if (mt->pitch != region->pitch) {
       fprintf(stderr,
 	      "region pitch (%d) doesn't match mipmap tree pitch (%d)\n",
 	      region->pitch, mt->pitch);
       free(mt);
       return NULL;
    }
 #else
    /* The mipmap tree pitch is aligned to 64 bytes to make sure render
     * to texture works, but we don't need that for texturing from a
     * pixmap.  Just override it here. */
    mt->pitch = region->pitch;
 #endif

    intel_region_reference(&mt->region, region);

    return mt;
 }


 /**
  * intel_miptree_pitch_align:
  *
  * @intel: intel context pointer
  *
  * @mt: the miptree to compute pitch alignment for
  *
  * @pitch: the natural pitch value
  *
  * Given @pitch, compute a larger value which accounts for
  * any necessary alignment required by the device
  */
 int intel_miptree_pitch_align (struct intel_context *intel,
 			       struct intel_mipmap_tree *mt,
 			       uint32_t tiling,
 			       int pitch)
 {
 #ifdef I915
    GLcontext *ctx = &intel->ctx;
 #endif

    if (!mt->compressed) {
       int pitch_align;

       /* XXX: Align pitch to multiple of 64 bytes for now to allow
        * render-to-texture to work in all cases. This should probably be
        * replaced at some point by some scheme to only do this when really
        * necessary.
        */
       pitch_align = 64;

       if (tiling == I915_TILING_X)
 	 pitch_align = 512;
       else if (tiling == I915_TILING_Y)
 	 pitch_align = 128;

       pitch = ALIGN(pitch * mt->cpp, pitch_align);

 #ifdef I915
       /* XXX: At least the i915 seems very upset when the pitch is a multiple
        * of 1024 and sometimes 512 bytes - performance can drop by several
        * times. Go to the next multiple of the required alignment for now.
        */
       if (!(pitch & 511) &&
 	 (pitch + pitch_align) < (1 << ctx->Const.MaxTextureLevels))
 	 pitch += pitch_align;
 #endif

       pitch /= mt->cpp;
    }
    return pitch;
 }


 void
 intel_miptree_reference(struct intel_mipmap_tree **dst,
                         struct intel_mipmap_tree *src)
 {
    src->refcount++;
    *dst = src;
    DBG("%s %p refcount now %d\n", __FUNCTION__, src, src->refcount);
 }


 void
 intel_miptree_release(struct intel_context *intel,
                       struct intel_mipmap_tree **mt)
 {
    if (!*mt)
       return;

    DBG("%s %p refcount will be %d\n", __FUNCTION__, *mt, (*mt)->refcount - 1);
    if (--(*mt)->refcount <= 0) {
       GLuint i;

       DBG("%s deleting %p\n", __FUNCTION__, *mt);

 #ifndef I915
       /* Free up cached binding tables holding a reference on our buffer, to
        * avoid excessive memory consumption.
        *
        * This isn't as aggressive as we could be, as we'd like to do
        * it from any time we free the last ref on a region.  But intel_region.c
        * is context-agnostic.  Perhaps our constant state cache should be, as
        * well.
        */
       brw_state_cache_bo_delete(&brw_context(&intel->ctx)->surface_cache,
 				(*mt)->region->buffer);
 #endif

       intel_region_release(&((*mt)->region));

       for (i = 0; i < MAX_TEXTURE_LEVELS; i++) {
 	 free((*mt)->level[i].x_offset);
 	 free((*mt)->level[i].y_offset);
       }

       free(*mt);
    }
    *mt = NULL;
 }


 /**
  * Can the image be pulled into a unified mipmap tree?  This mirrors
  * the completeness test in a lot of ways.
  *
  * Not sure whether I want to pass gl_texture_image here.
  */
 GLboolean
 intel_miptree_match_image(struct intel_mipmap_tree *mt,
                           struct gl_texture_image *image)
 {
    GLboolean isCompressed = _mesa_is_format_compressed(image->TexFormat);
    struct intel_texture_image *intelImage = intel_texture_image(image);
    GLuint level = intelImage->level;

    /* Images with borders are never pulled into mipmap trees. */
    if (image->Border)
       return GL_FALSE;

    if (image->InternalFormat != mt->internal_format ||
        isCompressed != mt->compressed)
       return GL_FALSE;

    if (!isCompressed &&
        !mt->compressed &&
        _mesa_get_format_bytes(image->TexFormat) != mt->cpp)
       return GL_FALSE;

    /* Test image dimensions against the base level image adjusted for
     * minification.  This will also catch images not present in the
     * tree, changed targets, etc.
     */
    if (image->Width != mt->level[level].width ||
        image->Height != mt->level[level].height ||
        image->Depth != mt->level[level].depth)
       return GL_FALSE;

    return GL_TRUE;
 }


 void
 intel_miptree_set_level_info(struct intel_mipmap_tree *mt,
 			     GLuint level,
 			     GLuint nr_images,
 			     GLuint x, GLuint y,
 			     GLuint w, GLuint h, GLuint d)
 {
    mt->level[level].width = w;
    mt->level[level].height = h;
    mt->level[level].depth = d;
    mt->level[level].level_offset = (x + y * mt->pitch) * mt->cpp;
    mt->level[level].level_x = x;
    mt->level[level].level_y = y;
    mt->level[level].nr_images = nr_images;

    DBG("%s level %d size: %d,%d,%d offset %d,%d (0x%x)\n", __FUNCTION__,
        level, w, h, d, x, y, mt->level[level].level_offset);

    assert(nr_images);
    assert(!mt->level[level].x_offset);

    mt->level[level].x_offset = malloc(nr_images * sizeof(GLuint));
    mt->level[level].x_offset[0] = mt->level[level].level_x;
    mt->level[level].y_offset = malloc(nr_images * sizeof(GLuint));
    mt->level[level].y_offset[0] = mt->level[level].level_y;
 }


 void
 intel_miptree_set_image_offset(struct intel_mipmap_tree *mt,
 			       GLuint level, GLuint img,
 			       GLuint x, GLuint y)
 {
    if (img == 0 && level == 0)
       assert(x == 0 && y == 0);

    assert(img < mt->level[level].nr_images);

    mt->level[level].x_offset[img] = mt->level[level].level_x + x;
    mt->level[level].y_offset[img] = mt->level[level].level_y + y;

    DBG("%s level %d img %d pos %d,%d\n",
        __FUNCTION__, level, img,
        mt->level[level].x_offset[img], mt->level[level].y_offset[img]);
 }


 void
 intel_miptree_get_image_offset(struct intel_mipmap_tree *mt,
 			       GLuint level, GLuint face, GLuint depth,
 			       GLuint *x, GLuint *y)
 {
    if (mt->target == GL_TEXTURE_CUBE_MAP_ARB) {
       *x = mt->level[level].x_offset[face];
       *y = mt->level[level].y_offset[face];
    } else if (mt->target == GL_TEXTURE_3D) {
       *x = mt->level[level].x_offset[depth];
       *y = mt->level[level].y_offset[depth];
    } else {
       *x = mt->level[level].x_offset[0];
       *y = mt->level[level].y_offset[0];
    }
 }

 /**
  * Map a teximage in a mipmap tree.
  * \param row_stride  returns row stride in bytes
  * \param image_stride  returns image stride in bytes (for 3D textures).
  * \param image_offsets pointer to array of pixel offsets from the returned
  *	  pointer to each depth image
  * \return address of mapping
  */
 GLubyte *
 intel_miptree_image_map(struct intel_context * intel,
                         struct intel_mipmap_tree * mt,
                         GLuint face,
                         GLuint level,
                         GLuint * row_stride, GLuint * image_offsets)
 {
    GLuint x, y;
    DBG("%s \n", __FUNCTION__);

    if (row_stride)
       *row_stride = mt->pitch * mt->cpp;

    if (mt->target == GL_TEXTURE_3D) {
       int i;

       for (i = 0; i < mt->level[level].depth; i++) {

 	 intel_miptree_get_image_offset(mt, level, face, i,
 					&x, &y);
 	 image_offsets[i] = x + y * mt->pitch;
       }

       return intel_region_map(intel, mt->region);
    } else {
       assert(mt->level[level].depth == 1);
       intel_miptree_get_image_offset(mt, level, face, 0,
 				     &x, &y);
       image_offsets[0] = 0;

       return intel_region_map(intel, mt->region) +
 	 (x + y * mt->pitch) * mt->cpp;
    }
 }


 void
 intel_miptree_image_unmap(struct intel_context *intel,
                           struct intel_mipmap_tree *mt)
 {
    DBG("%s\n", __FUNCTION__);
    intel_region_unmap(intel, mt->region);
 }


 /**
  * Upload data for a particular image.
  */
 void
 intel_miptree_image_data(struct intel_context *intel,
 			 struct intel_mipmap_tree *dst,
 			 GLuint face,
 			 GLuint level,
 			 void *src,
 			 GLuint src_row_pitch,
 			 GLuint src_image_pitch)
 {
    const GLuint depth = dst->level[level].depth;
    GLuint i;

    DBG("%s: %d/%d\n", __FUNCTION__, face, level);
    for (i = 0; i < depth; i++) {
       GLuint dst_x, dst_y, height;

       intel_miptree_get_image_offset(dst, level, face, i, &dst_x, &dst_y);

       height = dst->level[level].height;
       if(dst->compressed)
 	 height = (height + 3) / 4;

       intel_region_data(intel,
 			dst->region, 0, dst_x, dst_y,
 			src,
 			src_row_pitch,
 			0, 0,                             /* source x, y */
 			dst->level[level].width, height); /* width, height */

       src = (char *)src + src_image_pitch * dst->cpp;
    }
 }


 /**
  * Copy mipmap image between trees
  */
 void
 intel_miptree_image_copy(struct intel_context *intel,
                          struct intel_mipmap_tree *dst,
                          GLuint face, GLuint level,
                          struct intel_mipmap_tree *src)
 {
    GLuint width = src->level[level].width;
    GLuint height = src->level[level].height;
    GLuint depth = src->level[level].depth;
    GLuint src_x, src_y, dst_x, dst_y;
    GLuint i;
    GLboolean success;

    if (dst->compressed) {
        GLuint align_w, align_h;

        intel_get_texture_alignment_unit(dst->internal_format,
                                         &align_w, &align_h);
        height = (height + 3) / 4;
        width = ALIGN(width, align_w);
    }

    for (i = 0; i < depth; i++) {
       intel_miptree_get_image_offset(src, level, face, i, &src_x, &src_y);
       intel_miptree_get_image_offset(dst, level, face, i, &dst_x, &dst_y);
       success = intel_region_copy(intel,
 				  dst->region, 0, dst_x, dst_y,
 				  src->region, 0, src_x, src_y, width, height,
 				  GL_COPY);
       if (!success) {
 	 GLubyte *src_ptr, *dst_ptr;

 	 src_ptr = intel_region_map(intel, src->region);
 	 dst_ptr = intel_region_map(intel, dst->region);

 	 _mesa_copy_rect(dst_ptr + dst->cpp * (dst_x + dst_y * dst->pitch),
 			 dst->cpp,
 			 dst->pitch,
 			 0, 0, width, height,
 			 src_ptr + src->cpp * (src_x + src_y * src->pitch),
 			 src->pitch,
 			 0, 0);
 	 intel_region_unmap(intel, src->region);
 	 intel_region_unmap(intel, dst->region);
       }
    }
 }
	/**************************************************************************
	*
	* Copyright 2006 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 "intel_context.h"
	#include "intel_mipmap_tree.h"
	#include "intel_regions.h"
	#include "intel_tex_layout.h"
	#include "intel_chipset.h"
	#ifndef I915
	#include "brw_state.h"
	#endif
	#include "main/enums.h"

	#define FILE_DEBUG_FLAG DEBUG_MIPTREE


	static GLenum
	target_to_target(GLenum target)
	{
	switch (target) {
	case GL_TEXTURE_CUBE_MAP_POSITIVE_X_ARB:
	case GL_TEXTURE_CUBE_MAP_NEGATIVE_X_ARB:
	case GL_TEXTURE_CUBE_MAP_POSITIVE_Y_ARB:
	case GL_TEXTURE_CUBE_MAP_NEGATIVE_Y_ARB:
	case GL_TEXTURE_CUBE_MAP_POSITIVE_Z_ARB:
	case GL_TEXTURE_CUBE_MAP_NEGATIVE_Z_ARB:
	return GL_TEXTURE_CUBE_MAP_ARB;
	default:
	return target;
	}
	}


	static struct intel_mipmap_tree *
	intel_miptree_create_internal(struct intel_context *intel,
	GLenum target,
	GLenum internal_format,
	GLuint first_level,
	GLuint last_level,
	GLuint width0,
	GLuint height0,
	GLuint depth0, GLuint cpp, GLuint compress_byte,
	uint32_t tiling)
	{
	GLboolean ok;
	struct intel_mipmap_tree mt = calloc(sizeof(mt), 1);

	DBG("%s target %s format %s level %d..%d <-- %p\n", __FUNCTION__,
	_mesa_lookup_enum_by_nr(target),
	_mesa_lookup_enum_by_nr(internal_format),
	first_level, last_level, mt);

	mt->target = target_to_target(target);
	mt->internal_format = internal_format;
	mt->first_level = first_level;
	mt->last_level = last_level;
	mt->width0 = width0;
	mt->height0 = height0;
	mt->depth0 = depth0;
	mt->cpp = compress_byte ? compress_byte : cpp;
	mt->compressed = compress_byte ? 1 : 0;
	mt->refcount = 1;
	mt->pitch = 0;

	#ifdef I915
	if (intel->is_945)
	ok = i945_miptree_layout(intel, mt, tiling);
	else
	ok = i915_miptree_layout(intel, mt, tiling);
	#else
	ok = brw_miptree_layout(intel, mt, tiling);
	#endif

	if (!ok) {
	free(mt);
	DBG("%s not okay - returning NULL\n", __FUNCTION__);
	return NULL;
	}

	return mt;
	}


	struct intel_mipmap_tree *
	intel_miptree_create(struct intel_context *intel,
	GLenum target,
	GLenum base_format,
	GLenum internal_format,
	GLuint first_level,
	GLuint last_level,
	GLuint width0,
	GLuint height0,
	GLuint depth0, GLuint cpp, GLuint compress_byte,
	GLboolean expect_accelerated_upload)
	{
	struct intel_mipmap_tree *mt;
	uint32_t tiling;

	if (intel->use_texture_tiling && compress_byte == 0 &&
	intel->intelScreen->kernel_exec_fencing) {
	if (intel->gen >= 4 &&
	(base_format == GL_DEPTH_COMPONENT \|\|
	base_format == GL_DEPTH_STENCIL_EXT))
	tiling = I915_TILING_Y;
	else
	tiling = I915_TILING_X;
	} else
	tiling = I915_TILING_NONE;

	mt = intel_miptree_create_internal(intel, target, internal_format,
	first_level, last_level, width0,
	height0, depth0, cpp, compress_byte,
	tiling);
	/*
	* pitch == 0 \|\| height == 0 indicates the null texture
	*/
	if (!mt \|\| !mt->pitch \|\| !mt->total_height) {
	free(mt);
	return NULL;
	}

	mt->region = intel_region_alloc(intel,
	tiling,
	mt->cpp,
	mt->pitch,
	mt->total_height,
	mt->pitch,
	expect_accelerated_upload);

	if (!mt->region) {
	free(mt);
	return NULL;
	}

	return mt;
	}


	struct intel_mipmap_tree *
	intel_miptree_create_for_region(struct intel_context *intel,
	GLenum target,
	GLenum internal_format,
	GLuint first_level,
	GLuint last_level,
	struct intel_region *region,
	GLuint depth0,
	GLuint compress_byte)
	{
	struct intel_mipmap_tree *mt;

	mt = intel_miptree_create_internal(intel, target, internal_format,
	first_level, last_level,
	region->width, region->height, 1,
	region->cpp, compress_byte,
	I915_TILING_NONE);
	if (!mt)
	return mt;
	#if 0
	if (mt->pitch != region->pitch) {
	fprintf(stderr,
	"region pitch (%d) doesn't match mipmap tree pitch (%d)\n",
	region->pitch, mt->pitch);
	free(mt);
	return NULL;
	}
	#else
	/* The mipmap tree pitch is aligned to 64 bytes to make sure render
	* to texture works, but we don't need that for texturing from a
	* pixmap. Just override it here. */
	mt->pitch = region->pitch;
	#endif

	intel_region_reference(&mt->region, region);

	return mt;
	}


	/**
	* intel_miptree_pitch_align:
	*
	* @intel: intel context pointer
	*
	* @mt: the miptree to compute pitch alignment for
	*
	* @pitch: the natural pitch value
	*
	* Given @pitch, compute a larger value which accounts for
	* any necessary alignment required by the device
	*/
	int intel_miptree_pitch_align (struct intel_context *intel,
	struct intel_mipmap_tree *mt,
	uint32_t tiling,
	int pitch)
	{
	#ifdef I915
	GLcontext *ctx = &intel->ctx;
	#endif

	if (!mt->compressed) {
	int pitch_align;

	/* XXX: Align pitch to multiple of 64 bytes for now to allow
	* render-to-texture to work in all cases. This should probably be
	* replaced at some point by some scheme to only do this when really
	* necessary.
	*/
	pitch_align = 64;

	if (tiling == I915_TILING_X)
	pitch_align = 512;
	else if (tiling == I915_TILING_Y)
	pitch_align = 128;

	pitch = ALIGN(pitch * mt->cpp, pitch_align);

	#ifdef I915
	/* XXX: At least the i915 seems very upset when the pitch is a multiple
	* of 1024 and sometimes 512 bytes - performance can drop by several
	* times. Go to the next multiple of the required alignment for now.
	*/
	if (!(pitch & 511) &&
	(pitch + pitch_align) < (1 << ctx->Const.MaxTextureLevels))
	pitch += pitch_align;
	#endif

	pitch /= mt->cpp;
	}
	return pitch;
	}


	void
	intel_miptree_reference(struct intel_mipmap_tree **dst,
	struct intel_mipmap_tree *src)
	{
	src->refcount++;
	*dst = src;
	DBG("%s %p refcount now %d\n", __FUNCTION__, src, src->refcount);
	}


	void
	intel_miptree_release(struct intel_context *intel,
	struct intel_mipmap_tree **mt)
	{
	if (!*mt)
	return;

	DBG("%s %p refcount will be %d\n", __FUNCTION__, mt, (mt)->refcount - 1);
	if (--(*mt)->refcount <= 0) {
	GLuint i;

	DBG("%s deleting %p\n", __FUNCTION__, *mt);

	#ifndef I915
	/* Free up cached binding tables holding a reference on our buffer, to
	* avoid excessive memory consumption.
	*
	* This isn't as aggressive as we could be, as we'd like to do
	* it from any time we free the last ref on a region. But intel_region.c
	* is context-agnostic. Perhaps our constant state cache should be, as
	* well.
	*/
	brw_state_cache_bo_delete(&brw_context(&intel->ctx)->surface_cache,
	(*mt)->region->buffer);
	#endif

	intel_region_release(&((*mt)->region));

	for (i = 0; i < MAX_TEXTURE_LEVELS; i++) {
	free((*mt)->level[i].x_offset);
	free((*mt)->level[i].y_offset);
	}

	free(*mt);
	}
	*mt = NULL;
	}


	/**
	* Can the image be pulled into a unified mipmap tree? This mirrors
	* the completeness test in a lot of ways.
	*
	* Not sure whether I want to pass gl_texture_image here.
	*/
	GLboolean
	intel_miptree_match_image(struct intel_mipmap_tree *mt,
	struct gl_texture_image *image)
	{
	GLboolean isCompressed = _mesa_is_format_compressed(image->TexFormat);
	struct intel_texture_image *intelImage = intel_texture_image(image);
	GLuint level = intelImage->level;

	/* Images with borders are never pulled into mipmap trees. */
	if (image->Border)
	return GL_FALSE;

	if (image->InternalFormat != mt->internal_format \|\|
	isCompressed != mt->compressed)
	return GL_FALSE;

	if (!isCompressed &&
	!mt->compressed &&
	_mesa_get_format_bytes(image->TexFormat) != mt->cpp)
	return GL_FALSE;

	/* Test image dimensions against the base level image adjusted for
	* minification. This will also catch images not present in the
	* tree, changed targets, etc.
	*/
	if (image->Width != mt->level[level].width \|\|
	image->Height != mt->level[level].height \|\|
	image->Depth != mt->level[level].depth)
	return GL_FALSE;

	return GL_TRUE;
	}


	void
	intel_miptree_set_level_info(struct intel_mipmap_tree *mt,
	GLuint level,
	GLuint nr_images,
	GLuint x, GLuint y,
	GLuint w, GLuint h, GLuint d)
	{
	mt->level[level].width = w;
	mt->level[level].height = h;
	mt->level[level].depth = d;
	mt->level[level].level_offset = (x + y * mt->pitch) * mt->cpp;
	mt->level[level].level_x = x;
	mt->level[level].level_y = y;
	mt->level[level].nr_images = nr_images;

	DBG("%s level %d size: %d,%d,%d offset %d,%d (0x%x)\n", __FUNCTION__,
	level, w, h, d, x, y, mt->level[level].level_offset);

	assert(nr_images);
	assert(!mt->level[level].x_offset);

	mt->level[level].x_offset = malloc(nr_images * sizeof(GLuint));
	mt->level[level].x_offset[0] = mt->level[level].level_x;
	mt->level[level].y_offset = malloc(nr_images * sizeof(GLuint));
	mt->level[level].y_offset[0] = mt->level[level].level_y;
	}


	void
	intel_miptree_set_image_offset(struct intel_mipmap_tree *mt,
	GLuint level, GLuint img,
	GLuint x, GLuint y)
	{
	if (img == 0 && level == 0)
	assert(x == 0 && y == 0);

	assert(img < mt->level[level].nr_images);

	mt->level[level].x_offset[img] = mt->level[level].level_x + x;
	mt->level[level].y_offset[img] = mt->level[level].level_y + y;

	DBG("%s level %d img %d pos %d,%d\n",
	__FUNCTION__, level, img,
	mt->level[level].x_offset[img], mt->level[level].y_offset[img]);
	}


	void
	intel_miptree_get_image_offset(struct intel_mipmap_tree *mt,
	GLuint level, GLuint face, GLuint depth,
	GLuint x, GLuint y)
	{
	if (mt->target == GL_TEXTURE_CUBE_MAP_ARB) {
	*x = mt->level[level].x_offset[face];
	*y = mt->level[level].y_offset[face];
	} else if (mt->target == GL_TEXTURE_3D) {
	*x = mt->level[level].x_offset[depth];
	*y = mt->level[level].y_offset[depth];
	} else {
	*x = mt->level[level].x_offset[0];
	*y = mt->level[level].y_offset[0];
	}
	}

	/**
	* Map a teximage in a mipmap tree.
	* \param row_stride returns row stride in bytes
	* \param image_stride returns image stride in bytes (for 3D textures).
	* \param image_offsets pointer to array of pixel offsets from the returned
	* pointer to each depth image
	* \return address of mapping
	*/
	GLubyte *
	intel_miptree_image_map(struct intel_context * intel,
	struct intel_mipmap_tree * mt,
	GLuint face,
	GLuint level,
	GLuint * row_stride, GLuint * image_offsets)
	{
	GLuint x, y;
	DBG("%s \n", __FUNCTION__);

	if (row_stride)
	row_stride = mt->pitch mt->cpp;

	if (mt->target == GL_TEXTURE_3D) {
	int i;

	for (i = 0; i < mt->level[level].depth; i++) {

	intel_miptree_get_image_offset(mt, level, face, i,
	&x, &y);
	image_offsets[i] = x + y * mt->pitch;
	}

	return intel_region_map(intel, mt->region);
	} else {
	assert(mt->level[level].depth == 1);
	intel_miptree_get_image_offset(mt, level, face, 0,
	&x, &y);
	image_offsets[0] = 0;

	return intel_region_map(intel, mt->region) +
	(x + y * mt->pitch) * mt->cpp;
	}
	}


	void
	intel_miptree_image_unmap(struct intel_context *intel,
	struct intel_mipmap_tree *mt)
	{
	DBG("%s\n", __FUNCTION__);
	intel_region_unmap(intel, mt->region);
	}


	/**
	* Upload data for a particular image.
	*/
	void
	intel_miptree_image_data(struct intel_context *intel,
	struct intel_mipmap_tree *dst,
	GLuint face,
	GLuint level,
	void *src,
	GLuint src_row_pitch,
	GLuint src_image_pitch)
	{
	const GLuint depth = dst->level[level].depth;
	GLuint i;

	DBG("%s: %d/%d\n", __FUNCTION__, face, level);
	for (i = 0; i < depth; i++) {
	GLuint dst_x, dst_y, height;

	intel_miptree_get_image_offset(dst, level, face, i, &dst_x, &dst_y);

	height = dst->level[level].height;
	if(dst->compressed)
	height = (height + 3) / 4;

	intel_region_data(intel,
	dst->region, 0, dst_x, dst_y,
	src,
	src_row_pitch,
	0, 0, /* source x, y */
	dst->level[level].width, height); /* width, height */

	src = (char )src + src_image_pitch dst->cpp;
	}
	}


	/**
	* Copy mipmap image between trees
	*/
	void
	intel_miptree_image_copy(struct intel_context *intel,
	struct intel_mipmap_tree *dst,
	GLuint face, GLuint level,
	struct intel_mipmap_tree *src)
	{
	GLuint width = src->level[level].width;
	GLuint height = src->level[level].height;
	GLuint depth = src->level[level].depth;
	GLuint src_x, src_y, dst_x, dst_y;
	GLuint i;
	GLboolean success;

	if (dst->compressed) {
	GLuint align_w, align_h;

	intel_get_texture_alignment_unit(dst->internal_format,
	&align_w, &align_h);
	height = (height + 3) / 4;
	width = ALIGN(width, align_w);
	}

	for (i = 0; i < depth; i++) {
	intel_miptree_get_image_offset(src, level, face, i, &src_x, &src_y);
	intel_miptree_get_image_offset(dst, level, face, i, &dst_x, &dst_y);
	success = intel_region_copy(intel,
	dst->region, 0, dst_x, dst_y,
	src->region, 0, src_x, src_y, width, height,
	GL_COPY);
	if (!success) {
	GLubyte src_ptr, dst_ptr;

	src_ptr = intel_region_map(intel, src->region);
	dst_ptr = intel_region_map(intel, dst->region);

	_mesa_copy_rect(dst_ptr + dst->cpp * (dst_x + dst_y * dst->pitch),
	dst->cpp,
	dst->pitch,
	0, 0, width, height,
	src_ptr + src->cpp * (src_x + src_y * src->pitch),
	src->pitch,
	0, 0);
	intel_region_unmap(intel, src->region);
	intel_region_unmap(intel, dst->region);
	}
	}
	}