/**
* \brief A fast path for glReadPixels
*
* This fast path is taken when the source format is BGRA, RGBA,
* A or L and when the texture memory is X- or Y-tiled. It downloads
* the source data by directly mapping the memory without a GTT fence.
* This then needs to be de-tiled on the CPU before presenting the data to
* the user in the linear fasion.
*
* This is a performance win over the conventional texture download path.
* In the conventional texture download path, the texture is either mapped
* through the GTT or copied to a linear buffer with the blitter before
* handing off to a software path. This allows us to avoid round-tripping
* through the GPU (in the case where we would be blitting) and do only a
* single copy operation.
*/
static bool
intel_readpixels_tiled_memcpy(struct gl_context * ctx,
GLint xoffset, GLint yoffset,
GLsizei width, GLsizei height,
GLenum format, GLenum type,
GLvoid * pixels,
const struct gl_pixelstore_attrib *pack)
{
struct brw_context *brw = brw_context(ctx);
struct gl_renderbuffer *rb = ctx->ReadBuffer->_ColorReadBuffer;
const struct gen_device_info *devinfo = &brw->screen->devinfo;
/* This path supports reading from color buffers only */
if (rb == NULL)
return false;
struct intel_renderbuffer *irb = intel_renderbuffer(rb);
int dst_pitch;
/* The miptree's buffer. */
struct brw_bo *bo;
uint32_t cpp;
mem_copy_fn mem_copy = NULL;
/* This fastpath is restricted to specific renderbuffer types:
* a 2D BGRA, RGBA, L8 or A8 texture. It could be generalized to support
* more types.
*/
if (!devinfo->has_llc ||
!(type == GL_UNSIGNED_BYTE || type == GL_UNSIGNED_INT_8_8_8_8_REV) ||
pixels == NULL ||
_mesa_is_bufferobj(pack->BufferObj) ||
pack->Alignment > 4 ||
pack->SkipPixels > 0 ||
pack->SkipRows > 0 ||
(pack->RowLength != 0 && pack->RowLength != width) ||
pack->SwapBytes ||
pack->LsbFirst ||
pack->Invert)
return false;
/* Only a simple blit, no scale, bias or other mapping. */
if (ctx->_ImageTransferState)
return false;
/* It is possible that the renderbuffer (or underlying texture) is
* multisampled. Since ReadPixels from a multisampled buffer requires a
* multisample resolve, we can't handle this here
*/
if (rb->NumSamples > 1)
return false;
/* We can't handle copying from RGBX or BGRX because the tiled_memcpy
* function doesn't set the last channel to 1. Note this checks BaseFormat
* rather than TexFormat in case the RGBX format is being simulated with an
* RGBA format.
*/
if (rb->_BaseFormat == GL_RGB)
return false;
if (!intel_get_memcpy(rb->Format, format, type, &mem_copy, &cpp))
return false;
if (!irb->mt ||
(irb->mt->surf.tiling != ISL_TILING_X &&
irb->mt->surf.tiling != ISL_TILING_Y0)) {
/* The algorithm is written only for X- or Y-tiled memory. */
return false;
}
/* tiled_to_linear() assumes that if the object is swizzled, it is using
* I915_BIT6_SWIZZLE_9_10 for X and I915_BIT6_SWIZZLE_9 for Y. This is only
* true on gen5 and above.
*
* The killer on top is that some gen4 have an L-shaped swizzle mode, where
* parts of the memory aren't swizzled at all. Userspace just can't handle
* that.
*/
if (devinfo->gen < 5 && brw->has_swizzling)
return false;
/* Since we are going to read raw data to the miptree, we need to resolve
* any pending fast color clears before we start.
*/
intel_miptree_access_raw(brw, irb->mt, irb->mt_level, irb->mt_layer, false);
bo = irb->mt->bo;
if (brw_batch_references(&brw->batch, bo)) {
perf_debug("Flushing before mapping a referenced bo.\n");
intel_batchbuffer_flush(brw);
}
void *map = brw_bo_map(brw, bo, MAP_READ | MAP_RAW);
if (map == NULL) {
DBG("%s: failed to map bo\n", __func__);
return false;
}
unsigned slice_offset_x, slice_offset_y;
intel_miptree_get_image_offset(irb->mt, irb->mt_level, irb->mt_layer,
&slice_offset_x, &slice_offset_y);
xoffset += slice_offset_x;
yoffset += slice_offset_y;
dst_pitch = _mesa_image_row_stride(pack, width, format, type);
/* For a window-system renderbuffer, the buffer is actually flipped
* vertically, so we need to handle that. Since the detiling function
* can only really work in the forwards direction, we have to be a
* little creative. First, we compute the Y-offset of the first row of
* the renderbuffer (in renderbuffer coordinates). We then match that
* with the last row of the client's data. Finally, we give
* tiled_to_linear a negative pitch so that it walks through the
* client's data backwards as it walks through the renderbufer forwards.
*/
if (rb->Name == 0) {
yoffset = rb->Height - yoffset - height;
pixels += (ptrdiff_t) (height - 1) * dst_pitch;
dst_pitch = -dst_pitch;
}
/* We postponed printing this message until having committed to executing
* the function.
*/
DBG("%s: x,y=(%d,%d) (w,h)=(%d,%d) format=0x%x type=0x%x "
"mesa_format=0x%x tiling=%d "
"pack=(alignment=%d row_length=%d skip_pixels=%d skip_rows=%d)\n",
__func__, xoffset, yoffset, width, height,
format, type, rb->Format, irb->mt->surf.tiling,
pack->Alignment, pack->RowLength, pack->SkipPixels,
pack->SkipRows);
tiled_to_linear(
xoffset * cpp, (xoffset + width) * cpp,
yoffset, yoffset + height,
pixels - (ptrdiff_t) yoffset * dst_pitch - (ptrdiff_t) xoffset * cpp,
map + irb->mt->offset,
dst_pitch, irb->mt->surf.row_pitch,
brw->has_swizzling,
irb->mt->surf.tiling,
mem_copy
);
brw_bo_unmap(bo);
return true;
}
/**
* \brief A fast path for glGetTexImage.
*
* \see intel_readpixels_tiled_memcpy()
*/
bool
intel_gettexsubimage_tiled_memcpy(struct gl_context *ctx,
struct gl_texture_image *texImage,
GLint xoffset, GLint yoffset,
GLsizei width, GLsizei height,
GLenum format, GLenum type,
GLvoid *pixels,
const struct gl_pixelstore_attrib *packing)
{
struct brw_context *brw = brw_context(ctx);
struct intel_texture_image *image = intel_texture_image(texImage);
int dst_pitch;
/* The miptree's buffer. */
drm_intel_bo *bo;
int error = 0;
uint32_t cpp;
mem_copy_fn mem_copy = NULL;
/* This fastpath is restricted to specific texture types:
* a 2D BGRA, RGBA, L8 or A8 texture. It could be generalized to support
* more types.
*
* FINISHME: The restrictions below on packing alignment and packing row
* length are likely unneeded now because we calculate the destination stride
* with _mesa_image_row_stride. However, before removing the restrictions
* we need tests.
*/
if (!brw->has_llc ||
!(type == GL_UNSIGNED_BYTE || type == GL_UNSIGNED_INT_8_8_8_8_REV) ||
!(texImage->TexObject->Target == GL_TEXTURE_2D ||
texImage->TexObject->Target == GL_TEXTURE_RECTANGLE) ||
pixels == NULL ||
_mesa_is_bufferobj(packing->BufferObj) ||
packing->Alignment > 4 ||
packing->SkipPixels > 0 ||
packing->SkipRows > 0 ||
(packing->RowLength != 0 && packing->RowLength != width) ||
packing->SwapBytes ||
packing->LsbFirst ||
packing->Invert)
return false;
/* We can't handle copying from RGBX or BGRX because the tiled_memcpy
* function doesn't set the last channel to 1.
*/
if (texImage->TexFormat == MESA_FORMAT_B8G8R8X8_UNORM ||
texImage->TexFormat == MESA_FORMAT_R8G8B8X8_UNORM)
return false;
if (!intel_get_memcpy(texImage->TexFormat, format, type, &mem_copy, &cpp,
INTEL_DOWNLOAD))
return false;
/* If this is a nontrivial texture view, let another path handle it instead. */
if (texImage->TexObject->MinLayer)
return false;
if (!image->mt ||
(image->mt->tiling != I915_TILING_X &&
image->mt->tiling != I915_TILING_Y)) {
/* The algorithm is written only for X- or Y-tiled memory. */
return false;
}
/* Since we are going to write raw data to the miptree, we need to resolve
* any pending fast color clears before we start.
*/
intel_miptree_resolve_color(brw, image->mt);
bo = image->mt->bo;
if (drm_intel_bo_references(brw->batch.bo, bo)) {
perf_debug("Flushing before mapping a referenced bo.\n");
intel_batchbuffer_flush(brw);
}
error = brw_bo_map(brw, bo, false /* write enable */, "miptree");
if (error) {
DBG("%s: failed to map bo\n", __func__);
return false;
}
dst_pitch = _mesa_image_row_stride(packing, width, format, type);
DBG("%s: level=%d x,y=(%d,%d) (w,h)=(%d,%d) format=0x%x type=0x%x "
"mesa_format=0x%x tiling=%d "
"packing=(alignment=%d row_length=%d skip_pixels=%d skip_rows=%d)\n",
__func__, texImage->Level, xoffset, yoffset, width, height,
format, type, texImage->TexFormat, image->mt->tiling,
packing->Alignment, packing->RowLength, packing->SkipPixels,
packing->SkipRows);
int level = texImage->Level + texImage->TexObject->MinLevel;
/* Adjust x and y offset based on miplevel */
xoffset += image->mt->level[level].level_x;
yoffset += image->mt->level[level].level_y;
tiled_to_linear(
xoffset * cpp, (xoffset + width) * cpp,
yoffset, yoffset + height,
pixels - (ptrdiff_t) yoffset * dst_pitch - (ptrdiff_t) xoffset * cpp,
bo->virtual,
dst_pitch, image->mt->pitch,
brw->has_swizzling,
image->mt->tiling,
mem_copy
);
drm_intel_bo_unmap(bo);
return true;
}
/**
* \brief A fast path for glReadPixels
*
* This fast path is taken when the source format is BGRA, RGBA,
* A or L and when the texture memory is X- or Y-tiled. It downloads
* the source data by directly mapping the memory without a GTT fence.
* This then needs to be de-tiled on the CPU before presenting the data to
* the user in the linear fasion.
*
* This is a performance win over the conventional texture download path.
* In the conventional texture download path, the texture is either mapped
* through the GTT or copied to a linear buffer with the blitter before
* handing off to a software path. This allows us to avoid round-tripping
* through the GPU (in the case where we would be blitting) and do only a
* single copy operation.
*/
static bool
intel_readpixels_tiled_memcpy(struct gl_context * ctx,
GLint xoffset, GLint yoffset,
GLsizei width, GLsizei height,
GLenum format, GLenum type,
GLvoid * pixels,
const struct gl_pixelstore_attrib *pack)
{
struct brw_context *brw = brw_context(ctx);
struct gl_renderbuffer *rb = ctx->ReadBuffer->_ColorReadBuffer;
/* This path supports reading from color buffers only */
if (rb == NULL)
return false;
struct intel_renderbuffer *irb = intel_renderbuffer(rb);
int dst_pitch;
/* The miptree's buffer. */
drm_intel_bo *bo;
int error = 0;
uint32_t cpp;
mem_copy_fn mem_copy = NULL;
/* This fastpath is restricted to specific renderbuffer types:
* a 2D BGRA, RGBA, L8 or A8 texture. It could be generalized to support
* more types.
*/
if (!brw->has_llc ||
!(type == GL_UNSIGNED_BYTE || type == GL_UNSIGNED_INT_8_8_8_8_REV) ||
pixels == NULL ||
_mesa_is_bufferobj(pack->BufferObj) ||
pack->Alignment > 4 ||
pack->SkipPixels > 0 ||
pack->SkipRows > 0 ||
(pack->RowLength != 0 && pack->RowLength != width) ||
pack->SwapBytes ||
pack->LsbFirst ||
pack->Invert)
return false;
/* Only a simple blit, no scale, bias or other mapping. */
if (ctx->_ImageTransferState)
return false;
/* This renderbuffer can come from a texture. In this case, we impose
* some of the same restrictions we have for textures and adjust for
* miplevels.
*/
if (rb->TexImage) {
if (rb->TexImage->TexObject->Target != GL_TEXTURE_2D &&
rb->TexImage->TexObject->Target != GL_TEXTURE_RECTANGLE)
return false;
int level = rb->TexImage->Level + rb->TexImage->TexObject->MinLevel;
/* Adjust x and y offset based on miplevel */
xoffset += irb->mt->level[level].level_x;
yoffset += irb->mt->level[level].level_y;
}
/* It is possible that the renderbuffer (or underlying texture) is
* multisampled. Since ReadPixels from a multisampled buffer requires a
* multisample resolve, we can't handle this here
*/
if (rb->NumSamples > 1)
return false;
/* We can't handle copying from RGBX or BGRX because the tiled_memcpy
* function doesn't set the last channel to 1. Note this checks BaseFormat
* rather than TexFormat in case the RGBX format is being simulated with an
* RGBA format.
*/
if (rb->_BaseFormat == GL_RGB)
return false;
if (!intel_get_memcpy(rb->Format, format, type, &mem_copy, &cpp,
INTEL_DOWNLOAD))
return false;
if (!irb->mt ||
(irb->mt->tiling != I915_TILING_X &&
irb->mt->tiling != I915_TILING_Y)) {
/* The algorithm is written only for X- or Y-tiled memory. */
return false;
}
/* Since we are going to read raw data to the miptree, we need to resolve
* any pending fast color clears before we start.
*/
intel_miptree_resolve_color(brw, irb->mt);
bo = irb->mt->bo;
if (drm_intel_bo_references(brw->batch.bo, bo)) {
perf_debug("Flushing before mapping a referenced bo.\n");
intel_batchbuffer_flush(brw);
}
error = brw_bo_map(brw, bo, false /* write enable */, "miptree");
if (error) {
DBG("%s: failed to map bo\n", __func__);
return false;
}
dst_pitch = _mesa_image_row_stride(pack, width, format, type);
/* For a window-system renderbuffer, the buffer is actually flipped
* vertically, so we need to handle that. Since the detiling function
* can only really work in the forwards direction, we have to be a
* little creative. First, we compute the Y-offset of the first row of
* the renderbuffer (in renderbuffer coordinates). We then match that
* with the last row of the client's data. Finally, we give
* tiled_to_linear a negative pitch so that it walks through the
* client's data backwards as it walks through the renderbufer forwards.
*/
if (rb->Name == 0) {
yoffset = rb->Height - yoffset - height;
pixels += (ptrdiff_t) (height - 1) * dst_pitch;
dst_pitch = -dst_pitch;
}
/* We postponed printing this message until having committed to executing
* the function.
*/
DBG("%s: x,y=(%d,%d) (w,h)=(%d,%d) format=0x%x type=0x%x "
"mesa_format=0x%x tiling=%d "
"pack=(alignment=%d row_length=%d skip_pixels=%d skip_rows=%d)\n",
__func__, xoffset, yoffset, width, height,
format, type, rb->Format, irb->mt->tiling,
pack->Alignment, pack->RowLength, pack->SkipPixels,
pack->SkipRows);
tiled_to_linear(
xoffset * cpp, (xoffset + width) * cpp,
yoffset, yoffset + height,
pixels - (ptrdiff_t) yoffset * dst_pitch - (ptrdiff_t) xoffset * cpp,
bo->virtual,
dst_pitch, irb->mt->pitch,
brw->has_swizzling,
irb->mt->tiling,
mem_copy
);
drm_intel_bo_unmap(bo);
return true;
}
