From: Marek Olšák <marek.olsak@amd.com>
Date: Sat, 25 Nov 2017 19:16:02 +0000 (+0100)
Subject: radeonsi: don't use fast color clear for small surfaces
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=175ee084ff5e05398467ad66ea99ed812711f1a1;p=mesa.git

radeonsi: don't use fast color clear for small surfaces

This removes 35+ clear eliminate passes from DOTA 2.

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

diff --git a/src/gallium/drivers/radeonsi/si_clear.c b/src/gallium/drivers/radeonsi/si_clear.c
index 00589caf5be..4663fc29cc6 100644
--- a/src/gallium/drivers/radeonsi/si_clear.c
+++ b/src/gallium/drivers/radeonsi/si_clear.c
@@ -421,6 +421,17 @@ static void si_do_fast_color_clear(struct si_context *sctx,
 
 		bool need_decompress_pass = false;
 
+		/* Use a slow clear for small surfaces where the cost of
+		 * the eliminate pass can be higher than the benefit of fast
+		 * clear. The closed driver does this, but the numbers may differ.
+		 *
+		 * Always use fast clear on APUs.
+		 */
+		bool too_small = sctx->screen->b.info.has_dedicated_vram &&
+				 tex->resource.b.b.nr_samples <= 1 &&
+				 tex->resource.b.b.width0 <= 256 &&
+				 tex->resource.b.b.height0 <= 256;
+
 		/* Try to clear DCC first, otherwise try CMASK. */
 		if (vi_dcc_enabled(tex, 0)) {
 			uint32_t reset_value;
@@ -439,6 +450,9 @@ static void si_do_fast_color_clear(struct si_context *sctx,
 							  &clear_words_needed))
 				continue;
 
+			if (clear_words_needed && too_small)
+				continue;
+
 			/* DCC fast clear with MSAA should clear CMASK to 0xC. */
 			if (tex->resource.b.b.nr_samples >= 2 && tex->cmask.size) {
 				/* TODO: This doesn't work with MSAA. */
@@ -458,6 +472,9 @@ static void si_do_fast_color_clear(struct si_context *sctx,
 
 			tex->separate_dcc_dirty = true;
 		} else {
+			if (too_small)
+				continue;
+
 			/* 128-bit formats are unusupported */
 			if (tex->surface.bpe > 8) {
 				continue;