[Mesa-dev] [PATCH] r600g: don't enable ReZ mode on evergreen

[alexdeucher at gmail.com]

From: Alex Deucher <alexander.deucher at amd.com>

Can cause lockups in certain cases when
zfunc/zenable/zwrite change without a flush
in between.

Fixes:
https://bugs.freedesktop.org/show_bug.cgi?id=60969

This is a candidate for the 9.1 branch.

Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
---
 src/gallium/drivers/r600/evergreen_state.c |    5 ++++-
 1 files changed, 4 insertions(+), 1 deletions(-)

diff --git a/src/gallium/drivers/r600/evergreen_state.c b/src/gallium/drivers/r600/evergreen_state.c
index fd73613..4a91942 100644
--- a/src/gallium/drivers/r600/evergreen_state.c
+++ b/src/gallium/drivers/r600/evergreen_state.c
@@ -3536,9 +3536,12 @@ void evergreen_update_db_shader_control(struct r600_context * rctx)
 	 * write to the zbuffer. Write to zbuffer is delayed after fragment shader
 	 * execution and thus after alpha test so if discarded by the alpha test
 	 * the z value is not written.
+	 * If ReZ is enabled, and the zfunc/zenable/zwrite values change you can
+	 * get a hang unless you flush the DB in between.  For now just use
+	 * LATE_Z.
 	 */
 	if (rctx->alphatest_state.sx_alpha_test_control) {
-		db_shader_control |= S_02880C_Z_ORDER(V_02880C_RE_Z);
+		db_shader_control |= S_02880C_Z_ORDER(V_02880C_LATE_Z);
 	} else {
 		db_shader_control |= S_02880C_Z_ORDER(V_02880C_EARLY_Z_THEN_LATE_Z);
 	}
-- 
1.7.7.5