broadcom/vc5: Add support for centroid varyings.

It would be nice to share the flags packet emit logic with flat shade
flags, but I couldn't come up with a good way while still using our pack
macros.  We need to refactor this to shader record setup at compile time,
anyway.

Fixes ext_framebuffer_multisample-interpolation * centroid-*

4 files changed, 53 insertions, 4 deletions

diff --git a/src/gallium/drivers/vc5/vc5_context.h b/src/gallium/drivers/vc5/vc5_context.h
index e08a2a59909..9e55f80f947 100644
--- a/src/gallium/drivers/vc5/vc5_context.h
+++ b/src/gallium/drivers/vc5/vc5_context.h
@@ -82,6 +82,7 @@ void vc5_job_add_bo(struct vc5_job *job, struct vc5_bo *bo);
 #define VC5_DIRTY_FS_INPUTS     (1 << 26)
 #define VC5_DIRTY_STREAMOUT     (1 << 27)
 #define VC5_DIRTY_OQ            (1 << 28)
+#define VC5_DIRTY_CENTROID_FLAGS (1 << 29)
 
 #define VC5_MAX_FS_INPUTS 64
 
diff --git a/src/gallium/drivers/vc5/vc5_draw.c b/src/gallium/drivers/vc5/vc5_draw.c
index ff14d1c1358..ecb1aa37831 100644
--- a/src/gallium/drivers/vc5/vc5_draw.c
+++ b/src/gallium/drivers/vc5/vc5_draw.c
@@ -177,6 +177,9 @@ vc5_emit_gl_shader_state(struct vc5_context *vc5,
                         (vc5->prog.fs->prog_data.fs->writes_z ||
                          vc5->prog.fs->prog_data.fs->discard);
 
+                shader.fragment_shader_uses_real_pixel_centre_w_in_addition_to_centroid_w2 =
+                        vc5->prog.fs->prog_data.fs->uses_centroid_and_center_w;
+
                 shader.number_of_varyings_in_fragment_shader =
                         vc5->prog.fs->prog_data.base->num_inputs;
 
diff --git a/src/gallium/drivers/vc5/vc5_emit.c b/src/gallium/drivers/vc5/vc5_emit.c
index 0d11d7e1ad1..cb8af953300 100644
--- a/src/gallium/drivers/vc5/vc5_emit.c
+++ b/src/gallium/drivers/vc5/vc5_emit.c
@@ -589,6 +589,45 @@ v3dX(emit_state)(struct pipe_context *pctx)
                 }
         }
 
+#if V3D_VERSION >= 40
+        if (vc5->dirty & VC5_DIRTY_CENTROID_FLAGS) {
+                bool emitted_any = false;
+
+                for (int i = 0; i < ARRAY_SIZE(vc5->prog.fs->prog_data.fs->centroid_flags); i++) {
+                        if (!vc5->prog.fs->prog_data.fs->centroid_flags[i])
+                                continue;
+
+                        cl_emit(&job->bcl, CENTROID_FLAGS, flags) {
+                                flags.varying_offset_v0 = i;
+
+                                if (emitted_any) {
+                                        flags.action_for_centroid_flags_of_lower_numbered_varyings =
+                                                V3D_VARYING_FLAGS_ACTION_UNCHANGED;
+                                        flags.action_for_centroid_flags_of_higher_numbered_varyings =
+                                                V3D_VARYING_FLAGS_ACTION_UNCHANGED;
+                                } else {
+                                        flags.action_for_centroid_flags_of_lower_numbered_varyings =
+                                                ((i == 0) ?
+                                                 V3D_VARYING_FLAGS_ACTION_UNCHANGED :
+                                                 V3D_VARYING_FLAGS_ACTION_ZEROED);
+
+                                        flags.action_for_centroid_flags_of_higher_numbered_varyings =
+                                                V3D_VARYING_FLAGS_ACTION_ZEROED;
+                                }
+
+                                flags.centroid_flags_for_varyings_v024 =
+                                        vc5->prog.fs->prog_data.fs->centroid_flags[i];
+                        }
+
+                        emitted_any = true;
+                }
+
+                if (!emitted_any) {
+                        cl_emit(&job->bcl, ZERO_ALL_CENTROID_FLAGS, flags);
+                }
+        }
+#endif
+
         /* Set up the transform feedback data specs (which VPM entries to
          * output to which buffers).
          */
diff --git a/src/gallium/drivers/vc5/vc5_program.c b/src/gallium/drivers/vc5/vc5_program.c
index d885cdf2975..23d2d73a2dc 100644
--- a/src/gallium/drivers/vc5/vc5_program.c
+++ b/src/gallium/drivers/vc5/vc5_program.c
@@ -477,10 +477,16 @@ vc5_update_compiled_fs(struct vc5_context *vc5, uint8_t prim_mode)
 
         vc5->dirty |= VC5_DIRTY_COMPILED_FS;
 
-        if (old_fs &&
-            vc5->prog.fs->prog_data.fs->flat_shade_flags !=
-            old_fs->prog_data.fs->flat_shade_flags) {
-                vc5->dirty |= VC5_DIRTY_FLAT_SHADE_FLAGS;
+        if (old_fs) {
+                if (vc5->prog.fs->prog_data.fs->flat_shade_flags !=
+                    old_fs->prog_data.fs->flat_shade_flags) {
+                        vc5->dirty |= VC5_DIRTY_FLAT_SHADE_FLAGS;
+                }
+
+                if (vc5->prog.fs->prog_data.fs->centroid_flags !=
+                    old_fs->prog_data.fs->centroid_flags) {
+                        vc5->dirty |= VC5_DIRTY_CENTROID_FLAGS;
+                }
         }
 
         if (old_fs && memcmp(vc5->prog.fs->prog_data.fs->input_slots,