radeonsi: add DCC decompression (v2)

This is currently not needed but will be necessary when we have
features that do not work with DCC enabled, such as image stores
and sharing non-scanout surfaces.

v2: Marek: rebase, remove decompression from si_flush_resource (not needed)

Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Reviewed-by: Nicolai Hähnle <nicolai.haehnle@amd.com>

src/gallium/drivers/radeonsi/si_blit.c

@@ -271,18 +271,29 @@ void si_flush_depth_textures(struct si_context *sctx,
 static void si_blit_decompress_color(struct pipe_context *ctx,
 		struct r600_texture *rtex,
 		unsigned first_level, unsigned last_level,
-		unsigned first_layer, unsigned last_layer)
+		unsigned first_layer, unsigned last_layer,
+		bool need_dcc_decompress)
 {
 	struct si_context *sctx = (struct si_context *)ctx;
 	unsigned layer, level, checked_last_layer, max_layer;
 
-	if (!rtex->dirty_level_mask)
+	if (!rtex->dirty_level_mask && !need_dcc_decompress)
 		return;
 
 	for (level = first_level; level <= last_level; level++) {
-		if (!(rtex->dirty_level_mask & (1 << level)))
+		void* custom_blend;
+
+		if (!(rtex->dirty_level_mask & (1 << level)) && !need_dcc_decompress)
 			continue;
 
+		if (rtex->dcc_offset && need_dcc_decompress) {
+			custom_blend = sctx->custom_blend_dcc_decompress;
+		} else if (rtex->fmask.size) {
+			custom_blend = sctx->custom_blend_decompress;
+		} else {
+			custom_blend = sctx->custom_blend_fastclear;
+		}
+
 		/* The smaller the mipmap level, the less layers there are
 		 * as far as 3D textures are concerned. */
 		max_layer = util_max_layer(&rtex->resource.b.b, level);
@@ -298,9 +309,7 @@ static void si_blit_decompress_color(struct pipe_context *ctx,
 			cbsurf = ctx->create_surface(ctx, &rtex->resource.b.b, &surf_tmpl);
 
 			si_blitter_begin(ctx, SI_DECOMPRESS);
-			util_blitter_custom_color(sctx->blitter, cbsurf,
-				rtex->fmask.size ? sctx->custom_blend_decompress :
-						   sctx->custom_blend_fastclear);
+			util_blitter_custom_color(sctx->blitter, cbsurf, custom_blend);
 			si_blitter_end(ctx);
 
 			pipe_surface_reference(&cbsurf, NULL);
@@ -334,7 +343,8 @@ void si_decompress_color_textures(struct si_context *sctx,
 
 		si_blit_decompress_color(&sctx->b.b, tex,
 					 view->u.tex.first_level, view->u.tex.last_level,
-					 0, util_max_layer(&tex->resource.b.b, view->u.tex.first_level));
+					 0, util_max_layer(&tex->resource.b.b, view->u.tex.first_level),
+					 false);
 	}
 }
 
@@ -485,7 +495,7 @@ static void si_decompress_subresource(struct pipe_context *ctx,
 							  first_layer, last_layer);
 	} else if (rtex->fmask.size || rtex->cmask.size || rtex->dcc_offset) {
 		si_blit_decompress_color(ctx, rtex, level, level,
-					 first_layer, last_layer);
+					 first_layer, last_layer, false);
 	}
 }
 
@@ -763,7 +773,7 @@ static void si_flush_resource(struct pipe_context *ctx,
 
 	if (!rtex->is_depth && (rtex->cmask.size || rtex->dcc_offset)) {
 		si_blit_decompress_color(ctx, rtex, 0, res->last_level,
-					 0, util_max_layer(res, 0));
+					 0, util_max_layer(res, 0), false);
 	}
 }
 

src/gallium/drivers/radeonsi/si_pipe.c

@@ -68,6 +68,8 @@ static void si_destroy_context(struct pipe_context *context)
 		sctx->b.b.delete_blend_state(&sctx->b.b, sctx->custom_blend_decompress);
 	if (sctx->custom_blend_fastclear)
 		sctx->b.b.delete_blend_state(&sctx->b.b, sctx->custom_blend_fastclear);
+	if (sctx->custom_blend_dcc_decompress)
+		sctx->b.b.delete_blend_state(&sctx->b.b, sctx->custom_blend_dcc_decompress);
 	util_unreference_framebuffer_state(&sctx->framebuffer.state);
 
 	if (sctx->blitter)

src/gallium/drivers/radeonsi/si_pipe.h

@@ -196,6 +196,7 @@ struct si_context {
 	void				*custom_blend_resolve;
 	void				*custom_blend_decompress;
 	void				*custom_blend_fastclear;
+	void				*custom_blend_dcc_decompress;
 	void				*pstipple_sampler_state;
 	struct si_screen		*screen;
 	struct pipe_fence_handle	*last_gfx_fence;

src/gallium/drivers/radeonsi/si_state.c

@@ -3513,6 +3513,7 @@ void si_init_state_functions(struct si_context *sctx)
 	sctx->custom_blend_resolve = si_create_blend_custom(sctx, V_028808_CB_RESOLVE);
 	sctx->custom_blend_decompress = si_create_blend_custom(sctx, V_028808_CB_FMASK_DECOMPRESS);
 	sctx->custom_blend_fastclear = si_create_blend_custom(sctx, V_028808_CB_ELIMINATE_FAST_CLEAR);
+	sctx->custom_blend_dcc_decompress = si_create_blend_custom(sctx, V_028808_CB_DCC_DECOMPRESS);
 
 	sctx->b.b.set_clip_state = si_set_clip_state;
 	sctx->b.b.set_scissor_states = si_set_scissor_states;