r600g: don't enable ReZ mode on evergreen

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
and lockups on Civ4 with wine.

This is a candidate for the 9.1 branch.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Marek Olšák <maraeo@gmail.com>

diff --git a/src/gallium/drivers/r600/evergreen_state.c b/src/gallium/drivers/r600/evergreen_state.c
index fd73613871002df788ad184f3d3258292d931c44..4a9194253822196947122a454276daac0a2eee8e 100644 (file)
--- 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);
        }