--- /dev/null
+/*
+ * Copyright 2003 VMware, Inc.
+ * 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 VMWARE 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 "main/enums.h"
+#include "main/mtypes.h"
+#include "main/macros.h"
+#include "main/fbobject.h"
+#include "main/image.h"
+#include "main/bufferobj.h"
+#include "main/readpix.h"
+#include "main/state.h"
+#include "main/glformats.h"
+#include "program/prog_instruction.h"
+#include "drivers/common/meta.h"
+
+#include "brw_context.h"
+#include "brw_blorp.h"
+#include "intel_screen.h"
+#include "intel_batchbuffer.h"
+#include "intel_buffers.h"
+#include "intel_fbo.h"
+#include "intel_mipmap_tree.h"
+#include "intel_pixel.h"
+#include "intel_buffer_objects.h"
+
+#define FILE_DEBUG_FLAG DEBUG_PIXEL
+
+/**
+ * \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;
+ isl_memcpy_type copy_type;
+
+ /* 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;
+
+ copy_type = intel_miptree_get_memcpy_type(rb->Format, format, type, &cpp);
+ if (copy_type == ISL_MEMCPY_INVALID)
+ 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 (ctx->ReadBuffer->FlipY) {
+ 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);
+
+ isl_memcpy_tiled_to_linear(
+ xoffset * cpp, (xoffset + width) * cpp,
+ yoffset, yoffset + height,
+ pixels,
+ map + irb->mt->offset,
+ dst_pitch, irb->mt->surf.row_pitch_B,
+ brw->has_swizzling,
+ irb->mt->surf.tiling,
+ copy_type
+ );
+
+ brw_bo_unmap(bo);
+ return true;
+}
+
+static bool
+intel_readpixels_blorp(struct gl_context *ctx,
+ unsigned x, unsigned y,
+ unsigned w, unsigned h,
+ GLenum format, GLenum type, const void *pixels,
+ const struct gl_pixelstore_attrib *packing)
+{
+ struct brw_context *brw = brw_context(ctx);
+ struct gl_renderbuffer *rb = ctx->ReadBuffer->_ColorReadBuffer;
+ if (!rb)
+ return false;
+
+ struct intel_renderbuffer *irb = intel_renderbuffer(rb);
+
+ /* _mesa_get_readpixels_transfer_ops() includes the cases of read
+ * color clamping along with the ctx->_ImageTransferState.
+ */
+ if (_mesa_get_readpixels_transfer_ops(ctx, rb->Format, format,
+ type, GL_FALSE))
+ return false;
+
+ GLenum dst_base_format = _mesa_unpack_format_to_base_format(format);
+ if (_mesa_need_rgb_to_luminance_conversion(rb->_BaseFormat,
+ dst_base_format))
+ return false;
+
+ unsigned swizzle;
+ if (irb->Base.Base._BaseFormat == GL_RGB) {
+ swizzle = MAKE_SWIZZLE4(SWIZZLE_X, SWIZZLE_Y, SWIZZLE_Z, SWIZZLE_ONE);
+ } else {
+ swizzle = SWIZZLE_XYZW;
+ }
+
+ return brw_blorp_download_miptree(brw, irb->mt, rb->Format, swizzle,
+ irb->mt_level, x, y, irb->mt_layer,
+ w, h, 1, GL_TEXTURE_2D, format, type,
+ ctx->ReadBuffer->FlipY, pixels, packing);
+}
+
+void
+intelReadPixels(struct gl_context * ctx,
+ GLint x, GLint y, GLsizei width, GLsizei height,
+ GLenum format, GLenum type,
+ const struct gl_pixelstore_attrib *pack, GLvoid * pixels)
+{
+ bool ok;
+
+ struct brw_context *brw = brw_context(ctx);
+ bool dirty;
+
+ DBG("%s\n", __func__);
+
+ /* Reading pixels wont dirty the front buffer, so reset the dirty
+ * flag after calling intel_prepare_render().
+ */
+ dirty = brw->front_buffer_dirty;
+ intel_prepare_render(brw);
+ brw->front_buffer_dirty = dirty;
+
+ if (_mesa_is_bufferobj(pack->BufferObj)) {
+ if (intel_readpixels_blorp(ctx, x, y, width, height,
+ format, type, pixels, pack))
+ return;
+
+ perf_debug("%s: fallback to CPU mapping in PBO case\n", __func__);
+ }
+
+ ok = intel_readpixels_tiled_memcpy(ctx, x, y, width, height,
+ format, type, pixels, pack);
+ if(ok)
+ return;
+
+ /* Update Mesa state before calling _mesa_readpixels().
+ * XXX this may not be needed since ReadPixels no longer uses the
+ * span code.
+ */
+
+ if (ctx->NewState)
+ _mesa_update_state(ctx);
+
+ _mesa_readpixels(ctx, x, y, width, height, format, type, pack, pixels);
+
+ /* There's an intel_prepare_render() call in intelSpanRenderStart(). */
+ brw->front_buffer_dirty = dirty;
+}
projects / mesa.git / blobdiff