radeonsi/gfx9: don't flush TC L2 between rendering and texturing if not needed

Reviewed-by: Nicolai Hähnle <nicolai.haehnle@amd.com>

src/gallium/drivers/radeonsi/si_blit.c

@@ -391,29 +391,29 @@ si_decompress_depth(struct si_context *sctx,
 		/* Only in-place decompression needs to flush DB caches, or
 		 * when we don't decompress but TC-compatible planes are dirty.
 		 */
-		sctx->b.flags |= SI_CONTEXT_FLUSH_AND_INV_DB |
+		si_make_DB_shader_coherent(sctx, tex->resource.b.b.nr_samples,
-				 SI_CONTEXT_INV_GLOBAL_L2 |
+					   inplace_planes & PIPE_MASK_S);
-				 SI_CONTEXT_INV_VMEM_L1;
 
 		/* If we flush DB caches for TC-compatible depth, the dirty
 		 * state becomes 0 for the whole mipmap tree and all planes.
 		 * (there is nothing else to flush)
 		 */
 		if (tex->tc_compatible_htile) {
-			if (r600_can_sample_zs(tex, false))
+			/* Only clear the mask that we are flushing, because
+			 * si_make_DB_shader_coherent() can treat depth and
+			 * stencil differently.
+			 */
+			if (inplace_planes & PIPE_MASK_Z)
 				tex->dirty_level_mask = 0;
-			if (r600_can_sample_zs(tex, true))
+			if (inplace_planes & PIPE_MASK_S)
 				tex->stencil_dirty_level_mask = 0;
 		}
 	}
 	/* set_framebuffer_state takes care of coherency for single-sample.
 	 * The DB->CB copy uses CB for the final writes.
 	 */
-	if (copy_planes && tex->resource.b.b.nr_samples > 1) {
+	if (copy_planes && tex->resource.b.b.nr_samples > 1)
-		sctx->b.flags |= SI_CONTEXT_INV_VMEM_L1 |
+		si_make_CB_shader_coherent(sctx, tex->resource.b.b.nr_samples);
-				 SI_CONTEXT_INV_GLOBAL_L2 |
-				 SI_CONTEXT_FLUSH_AND_INV_CB;
-	}
 }
 
 static void
@@ -524,10 +524,7 @@ static void si_blit_decompress_color(struct pipe_context *ctx,
 	}
 
 	sctx->decompression_enabled = false;
-
+	si_make_CB_shader_coherent(sctx, rtex->resource.b.b.nr_samples);
-	sctx->b.flags |= SI_CONTEXT_FLUSH_AND_INV_CB |
-			 SI_CONTEXT_INV_GLOBAL_L2 |
-			 SI_CONTEXT_INV_VMEM_L1;
 }
 
 static void
@@ -1216,9 +1213,7 @@ static void si_do_CB_resolve(struct si_context *sctx,
 	si_blitter_end(&sctx->b.b);
 
 	/* Flush caches for possible texturing. */
-	sctx->b.flags |= SI_CONTEXT_FLUSH_AND_INV_CB |
+	si_make_CB_shader_coherent(sctx, 1);
-			 SI_CONTEXT_INV_GLOBAL_L2 |
-			 SI_CONTEXT_INV_VMEM_L1;
 }
 
 static bool do_hardware_msaa_resolve(struct pipe_context *ctx,

src/gallium/drivers/radeonsi/si_pipe.h

@@ -611,4 +611,27 @@ si_saved_cs_reference(struct si_saved_cs **dst, struct si_saved_cs *src)
 	*dst = src;
 }
 
+static inline void
+si_make_CB_shader_coherent(struct si_context *sctx, unsigned num_samples)
+{
+	sctx->b.flags |= SI_CONTEXT_FLUSH_AND_INV_CB |
+			 SI_CONTEXT_INV_VMEM_L1;
+
+	/* Single-sample color is coherent with shaders on GFX9. */
+	if (sctx->b.chip_class <= VI || num_samples >= 2)
+		sctx->b.flags |= SI_CONTEXT_INV_GLOBAL_L2;
+}
+
+static inline void
+si_make_DB_shader_coherent(struct si_context *sctx, unsigned num_samples,
+			   bool include_stencil)
+{
+	sctx->b.flags |= SI_CONTEXT_FLUSH_AND_INV_DB |
+			 SI_CONTEXT_INV_VMEM_L1;
+
+	/* Single-sample depth (not stencil) is coherent with shaders on GFX9. */
+	if (sctx->b.chip_class <= VI || num_samples >= 2 || include_stencil)
+		sctx->b.flags |= SI_CONTEXT_INV_GLOBAL_L2;
+}
+
 #endif

src/gallium/drivers/radeonsi/si_state.c

@@ -2572,11 +2572,9 @@ static void si_set_framebuffer_state(struct pipe_context *ctx,
 	 * Only flush and wait for CB if there is actually a bound color buffer.
 	 */
 	if (sctx->framebuffer.nr_samples <= 1 &&
-	    sctx->framebuffer.state.nr_cbufs) {
+	    sctx->framebuffer.state.nr_cbufs)
-		sctx->b.flags |= SI_CONTEXT_INV_VMEM_L1 |
+		si_make_CB_shader_coherent(sctx, sctx->framebuffer.nr_samples);
-				 SI_CONTEXT_INV_GLOBAL_L2 |
+
-				 SI_CONTEXT_FLUSH_AND_INV_CB;
-	}
 	sctx->b.flags |= SI_CONTEXT_CS_PARTIAL_FLUSH;
 
 	/* u_blitter doesn't invoke depth decompression when it does multiple
@@ -2585,11 +2583,8 @@ static void si_set_framebuffer_state(struct pipe_context *ctx,
 	 * individual generate_mipmap blits.
 	 * Note that lower mipmap levels aren't compressed.
 	 */
-	if (sctx->generate_mipmap_for_depth) {
+	if (sctx->generate_mipmap_for_depth)
-		sctx->b.flags |= SI_CONTEXT_INV_VMEM_L1 |
+		si_make_DB_shader_coherent(sctx, 1, false);
-				 SI_CONTEXT_INV_GLOBAL_L2 |
-				 SI_CONTEXT_FLUSH_AND_INV_DB;
-	}
 
 	/* Take the maximum of the old and new count. If the new count is lower,
 	 * dirtying is needed to disable the unbound colorbuffers.
@@ -4026,11 +4021,8 @@ static void si_texture_barrier(struct pipe_context *ctx, unsigned flags)
 
 	/* Multisample surfaces are flushed in si_decompress_textures. */
 	if (sctx->framebuffer.nr_samples <= 1 &&
-	    sctx->framebuffer.state.nr_cbufs) {
+	    sctx->framebuffer.state.nr_cbufs)
-		sctx->b.flags |= SI_CONTEXT_INV_VMEM_L1 |
+		si_make_CB_shader_coherent(sctx, sctx->framebuffer.nr_samples);
-				 SI_CONTEXT_INV_GLOBAL_L2 |
-				 SI_CONTEXT_FLUSH_AND_INV_CB;
-	}
 }
 
 /* This only ensures coherency for shader image/buffer stores. */
@@ -4073,8 +4065,11 @@ static void si_memory_barrier(struct pipe_context *ctx, unsigned flags)
 	if (flags & PIPE_BARRIER_FRAMEBUFFER &&
 	    sctx->framebuffer.nr_samples <= 1 &&
 	    sctx->framebuffer.state.nr_cbufs) {
-		sctx->b.flags |= SI_CONTEXT_FLUSH_AND_INV_CB |
+		sctx->b.flags |= SI_CONTEXT_FLUSH_AND_INV_CB;
-				 SI_CONTEXT_WRITEBACK_GLOBAL_L2;
+
+		/* Single-sample color is coherent with TC on GFX9. */
+		if (sctx->screen->b.chip_class <= VI)
+			sctx->b.flags |= SI_CONTEXT_WRITEBACK_GLOBAL_L2;
 	}
 
 	/* Indirect buffers use TC L2 on GFX9, but not older hw. */