[Mesa-dev] [PATCH] r600g: workaround hyperz lockup on evergreen

[j.glisse at gmail.com]

From: Jerome Glisse <jglisse at redhat.com>

This work around disable hyperz if write to zbuffer is disabled. Somehow
using hyperz when not writting to the zbuffer trigger GPU lockup. See :

https://bugs.freedesktop.org/show_bug.cgi?id=60848

Candidate for 9.1

Signed-off-by: Jerome Glisse <jglisse at redhat.com>
---
 src/gallium/drivers/r600/evergreen_state.c   | 10 +++++++++-
 src/gallium/drivers/r600/r600_pipe.h         |  4 +++-
 src/gallium/drivers/r600/r600_state.c        |  1 +
 src/gallium/drivers/r600/r600_state_common.c | 10 ++++++++++
 4 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/src/gallium/drivers/r600/evergreen_state.c b/src/gallium/drivers/r600/evergreen_state.c
index 4a91942..2e301bc 100644
--- a/src/gallium/drivers/r600/evergreen_state.c
+++ b/src/gallium/drivers/r600/evergreen_state.c
@@ -858,6 +858,7 @@ static void *evergreen_create_dsa_state(struct pipe_context *ctx,
 	dsa->valuemask[1] = state->stencil[1].valuemask;
 	dsa->writemask[0] = state->stencil[0].writemask;
 	dsa->writemask[1] = state->stencil[1].writemask;
+	dsa->zwritemask = state->depth.writemask;
 
 	db_depth_control = S_028800_Z_ENABLE(state->depth.enabled) |
 		S_028800_Z_WRITE_ENABLE(state->depth.writemask) |
@@ -2286,7 +2287,14 @@ static void evergreen_emit_db_misc_state(struct r600_context *rctx, struct r600_
 		}
 		db_render_override |= S_02800C_NOOP_CULL_DISABLE(1);
 	}
-	if (rctx->db_state.rsurf && rctx->db_state.rsurf->htile_enabled) {
+	/* FIXME we should be able to use hyperz even if we are not writing to
+	 * zbuffer but somehow this trigger GPU lockup. See :
+	 *
+	 * https://bugs.freedesktop.org/show_bug.cgi?id=60848
+	 *
+	 * Disable hyperz for now if not writing to zbuffer.
+	 */
+	if (rctx->db_state.rsurf && rctx->db_state.rsurf->htile_enabled && rctx->zwritemask) {
 		/* FORCE_OFF means HiZ/HiS are determined by DB_SHADER_CONTROL */
 		db_render_override |= S_02800C_FORCE_HIZ_ENABLE(V_02800C_FORCE_OFF);
 		/* This is to fix a lockup when hyperz and alpha test are enabled at
diff --git a/src/gallium/drivers/r600/r600_pipe.h b/src/gallium/drivers/r600/r600_pipe.h
index de9c205..5ebf98a 100644
--- a/src/gallium/drivers/r600/r600_pipe.h
+++ b/src/gallium/drivers/r600/r600_pipe.h
@@ -298,7 +298,8 @@ struct r600_dsa_state {
 	unsigned			alpha_ref;
 	ubyte				valuemask[2];
 	ubyte				writemask[2];
-	unsigned                        sx_alpha_test_control;
+	unsigned			zwritemask;
+	unsigned			sx_alpha_test_control;
 };
 
 struct r600_pipe_shader;
@@ -513,6 +514,7 @@ struct r600_context {
 	bool				alpha_to_one;
 	bool				force_blend_disable;
 	boolean				dual_src_blend;
+	unsigned			zwritemask;
 
 	/* Index buffer. */
 	struct pipe_index_buffer	index_buffer;
diff --git a/src/gallium/drivers/r600/r600_state.c b/src/gallium/drivers/r600/r600_state.c
index c6559bb..2d3ec93 100644
--- a/src/gallium/drivers/r600/r600_state.c
+++ b/src/gallium/drivers/r600/r600_state.c
@@ -842,6 +842,7 @@ static void *r600_create_dsa_state(struct pipe_context *ctx,
 	dsa->valuemask[1] = state->stencil[1].valuemask;
 	dsa->writemask[0] = state->stencil[0].writemask;
 	dsa->writemask[1] = state->stencil[1].writemask;
+	dsa->zwritemask = state->depth.writemask;
 
 	db_depth_control = S_028800_Z_ENABLE(state->depth.enabled) |
 		S_028800_Z_WRITE_ENABLE(state->depth.writemask) |
diff --git a/src/gallium/drivers/r600/r600_state_common.c b/src/gallium/drivers/r600/r600_state_common.c
index c4bd758..52b7d55 100644
--- a/src/gallium/drivers/r600/r600_state_common.c
+++ b/src/gallium/drivers/r600/r600_state_common.c
@@ -284,6 +284,16 @@ static void r600_bind_dsa_state(struct pipe_context *ctx, void *state)
 	ref.valuemask[1] = dsa->valuemask[1];
 	ref.writemask[0] = dsa->writemask[0];
 	ref.writemask[1] = dsa->writemask[1];
+	if (rctx->zwritemask != dsa->zwritemask) {
+		rctx->zwritemask = dsa->zwritemask;
+		if (rctx->chip_class >= EVERGREEN) {
+			/* work around some issue when not writting to zbuffer
+			 * we are having lockup on evergreen so do not enable
+			 * hyperz when not writting zbuffer
+			 */
+			rctx->db_misc_state.atom.dirty = true;
+		}
+	}
 
 	r600_set_stencil_ref(ctx, &ref);
 
-- 
1.7.11.7