[Mesa-dev] [PATCH] radeonsi: don't flush and wait for CB after depth-only rendering

[Marek Olšák]

From: Marek Olšák <marek.olsak at amd.com>

---
 src/gallium/drivers/radeonsi/si_state.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/gallium/drivers/radeonsi/si_state.c b/src/gallium/drivers/radeonsi/si_state.c
index 0f39ede..b236bed 100644
--- a/src/gallium/drivers/radeonsi/si_state.c
+++ b/src/gallium/drivers/radeonsi/si_state.c
@@ -2528,22 +2528,25 @@ static void si_set_framebuffer_state(struct pipe_context *ctx,
 	 * Wait for compute shaders because of possible transitions:
 	 * - FB write -> shader read
 	 * - shader write -> FB read
 	 *
 	 * DB caches are flushed on demand (using si_decompress_textures).
 	 *
 	 * When MSAA is enabled, CB and TC caches are flushed on demand
 	 * (after FMASK decompression). Shader write -> FB read transitions
 	 * cannot happen for MSAA textures, because MSAA shader images are
 	 * not supported.
+	 *
+	 * Only flush and wait for CB if there is actually a bound color buffer.
 	 */
-	if (sctx->framebuffer.nr_samples <= 1) {
+	if (sctx->framebuffer.nr_samples <= 1 &&
+	    sctx->framebuffer.state.nr_cbufs) {
 		sctx->b.flags |= SI_CONTEXT_INV_VMEM_L1 |
 				 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
 	 * blits in a row, but the only case when it matters for DB is when
 	 * doing generate_mipmap. So here we flush DB manually between
 	 * individual generate_mipmap blits.
-- 
2.7.4