/* * 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 "drivers/common/meta.h" #include "brw_context.h" #include "intel_screen.h" #include "intel_batchbuffer.h" #include "intel_blit.h" #include "intel_buffers.h" #include "intel_fbo.h" #include "intel_mipmap_tree.h" #include "intel_pixel.h" #include "intel_buffer_objects.h" #include "intel_tiled_memcpy.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; /* 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; /* 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->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_all_slices_resolve_color(brw, irb->mt, 0); 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; } xoffset += irb->mt->level[irb->mt_level].slice[irb->mt_layer].x_offset; yoffset += irb->mt->level[irb->mt_level].slice[irb->mt_layer].y_offset; 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 + irb->mt->offset, dst_pitch, irb->mt->pitch, brw->has_swizzling, irb->mt->tiling, mem_copy ); drm_intel_bo_unmap(bo); return true; } 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__); if (_mesa_is_bufferobj(pack->BufferObj)) { if (_mesa_meta_pbo_GetTexSubImage(ctx, 2, NULL, x, y, 0, width, height, 1, format, type, pixels, pack)) { /* _mesa_meta_pbo_GetTexSubImage() implements PBO transfers by * binding the user-provided BO as a fake framebuffer and rendering * to it. This breaks the invariant of the GL that nothing is able * to render to a BO, causing nondeterministic corruption issues * because the render cache is not coherent with a number of other * caches that the BO could potentially be bound to afterwards. * * This could be solved in the same way that we guarantee texture * coherency after a texture is attached to a framebuffer and * rendered to, but that would involve checking *all* BOs bound to * the pipeline for the case we need to emit a cache flush due to * previous rendering to any of them -- Including vertex, index, * uniform, atomic counter, shader image, transform feedback, * indirect draw buffers, etc. * * That would increase the per-draw call overhead even though it's * very unlikely that any of the BOs bound to the pipeline has been * rendered to via a PBO at any point, so it seems better to just * flush here unconditionally. */ brw_emit_mi_flush(brw); 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; /* glReadPixels() 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; /* 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; }