gallium/radeon: discard CMASK or DCC if overwriting a whole texture by DMA

v2: simplify the conditionals

Reviewed-by: Alex Deucher <alexander.deucher@amd.com> (v1)
Reviewed-by: Nicolai Hähnle <nicolai.haehnle@amd.com>

diff --git a/src/gallium/drivers/radeon/r600_texture.c b/src/gallium/drivers/radeon/r600_texture.c
index 103b7b70053b0cc6c778d9f49681327dd401c05f..773d67a2f04f4ab65cb21e64ca7e670af74860f9 100644 (file)
--- a/src/gallium/drivers/radeon/r600_texture.c
+++ b/src/gallium/drivers/radeon/r600_texture.c
@@ -32,6 +32,23 @@
 #include <errno.h>
 #include <inttypes.h>
 
+static void r600_texture_discard_dcc(struct r600_common_screen *rscreen,
+                                    struct r600_texture *rtex);
+static void r600_texture_discard_cmask(struct r600_common_screen *rscreen,
+                                      struct r600_texture *rtex);
+
+
+static bool range_covers_whole_texture(struct pipe_resource *tex,
+                                      unsigned level, unsigned x, unsigned y,
+                                      unsigned z, unsigned width,
+                                      unsigned height, unsigned depth)
+{
+       return x == 0 && y == 0 && z == 0 &&
+              width == u_minify(tex->width0, level) &&
+              height == u_minify(tex->height0, level) &&
+              depth == util_max_layer(tex, level) + 1;
+}
+
 bool r600_prepare_for_dma_blit(struct r600_common_context *rctx,
                               struct r600_texture *rdst,
                               unsigned dst_level, unsigned dstx,
@@ -61,21 +78,36 @@ bool r600_prepare_for_dma_blit(struct r600_common_context *rctx,
 
        /* DCC as:
         *   src: Use the 3D path. DCC decompression is expensive.
-        *   dst: If overwriting the whole texture, disable DCC and use SDMA.
+        *   dst: If overwriting the whole texture, discard DCC and use SDMA.
         *        Otherwise, use the 3D path.
-        * TODO: handle the case when the dst box covers the whole texture
         */
-       if (rsrc->dcc_offset || rdst->dcc_offset)
+       if (rsrc->dcc_offset)
                return false;
 
+       if (rdst->dcc_offset) {
+               /* We can't discard DCC if the texture has been exported. */
+               if (rdst->resource.is_shared ||
+                   !range_covers_whole_texture(&rdst->resource.b.b, dst_level,
+                                               dstx, dsty, dstz, src_box->width,
+                                               src_box->height, src_box->depth))
+                       return false;
+
+               r600_texture_discard_dcc(rctx->screen, rdst);
+       }
+
        /* CMASK as:
         *   src: Both texture and SDMA paths need decompression. Use SDMA.
-        *   dst: If overwriting the whole texture, deallocate CMASK and use
+        *   dst: If overwriting the whole texture, discard CMASK and use
         *        SDMA. Otherwise, use the 3D path.
-        * TODO: handle the case when the dst box covers the whole texture
         */
-       if (rdst->cmask.size && rdst->dirty_level_mask & (1 << dst_level))
-               return false;
+       if (rdst->cmask.size && rdst->dirty_level_mask & (1 << dst_level)) {
+               if (!range_covers_whole_texture(&rdst->resource.b.b, dst_level,
+                                               dstx, dsty, dstz, src_box->width,
+                                               src_box->height, src_box->depth))
+                       return false;
+
+               r600_texture_discard_cmask(rctx->screen, rdst);
+       }
 
        /* All requirements are met. Prepare textures for SDMA. */
        if (rsrc->cmask.size && rsrc->dirty_level_mask & (1 << src_level))