panfrost: Add the MALI_WRITES_{Z,S} flags

We discovered 2 new shader flags used when a fragment shader updates
the depth/stencil value through a ZS writeout. If those flags are not
set, the depth/stencil value stored in the depth/stencil tilebuffer
remain unchanged.

While at it, rename unknown2 into flags_hi and rename flags into
flags_lo.

Signed-off-by: Boris Brezillon <[email protected]>
Reviewed-by: Alyssa Rosenzweig <[email protected]>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/merge_requests/3697>

1 files changed, 11 insertions, 3 deletions

diff --git a/src/panfrost/include/panfrost-job.h b/src/panfrost/include/panfrost-job.h
index 0861d10e509..1a59f4c77c8 100644
--- a/src/panfrost/include/panfrost-job.h
+++ b/src/panfrost/include/panfrost-job.h
@@ -384,7 +384,10 @@ enum mali_format {
 #define MALI_ALPHA_COVERAGE(clampf) ((uint16_t) (int) (clampf * 15.0f))
 #define MALI_GET_ALPHA_COVERAGE(nibble) ((float) nibble / 15.0f)
 
-/* Applies to midgard1.flags */
+/* Applies to midgard1.flags_lo */
+
+/* Should be set when the fragment shader updates the depth value. */
+#define MALI_WRITES_Z (1 << 4)
 
 /* Should the hardware perform early-Z testing? Normally should be set
  * for performance reasons. Clear if you use: discard,
@@ -406,6 +409,11 @@ enum mali_format {
 #define MALI_READS_ZS (1 << 8)
 #define MALI_READS_TILEBUFFER (1 << 12)
 
+/* Applies to midgard1.flags_hi */
+
+/* Should be set when the fragment shader updates the stencil value. */
+#define MALI_WRITES_S (1 << 2)
+
 /* The raw Midgard blend payload can either be an equation or a shader
  * address, depending on the context */
 
@@ -534,12 +542,12 @@ struct mali_shader_meta {
                 } bifrost1;
                 struct {
                         unsigned uniform_buffer_count : 4;
-                        unsigned flags : 12;
+                        unsigned flags_lo : 12;
 
                         /* vec4 units */
                         unsigned work_count : 5;
                         unsigned uniform_count : 5;
-                        unsigned unknown2 : 6;
+                        unsigned flags_hi : 6;
                 } midgard1;
         };