mesa/st: add sampler uniforms

Add sampler uniforms for the UV plane(s), so driver can count the
uniforms and get the correct sampler count.

Fixes lowered YUV on a6xx which actually wants to know # of samplers.

Signed-off-by: Rob Clark <[email protected]>
Reviewed-by: Kristian H. Kristensen <[email protected]>
Reviewed-by: Eric Anholt <[email protected]>

1 files changed, 45 insertions, 6 deletions

diff --git a/src/mesa/state_tracker/st_nir_lower_tex_src_plane.c b/src/mesa/state_tracker/st_nir_lower_tex_src_plane.c
index 609a9aa4bc7..db838612da8 100644
--- a/src/mesa/state_tracker/st_nir_lower_tex_src_plane.c
+++ b/src/mesa/state_tracker/st_nir_lower_tex_src_plane.c
@@ -33,7 +33,7 @@
 #include "st_nir.h"
 
 typedef struct {
-   struct shader_info *info;
+   struct nir_shader *shader;
 
    unsigned lower_2plane;
    unsigned lower_3plane;
@@ -44,6 +44,34 @@ typedef struct {
    unsigned char sampler_map[PIPE_MAX_SAMPLERS][2];
 } lower_tex_src_state;
 
+static nir_variable *
+find_sampler(lower_tex_src_state *state, unsigned samp)
+{
+   /* NOTE: arrays of samplerExternalOES do not appear to be allowed: */
+   nir_foreach_variable(var, &state->shader->uniforms)
+      if (var->data.binding == samp)
+         return var;
+   return NULL;
+}
+
+static void
+add_sampler(lower_tex_src_state *state, unsigned orig_binding,
+            unsigned new_binding, const char *ext)
+{
+   const struct glsl_type *samplerExternalOES =
+      glsl_sampler_type(GLSL_SAMPLER_DIM_EXTERNAL, false, false, GLSL_TYPE_FLOAT);
+   nir_variable *new_sampler, *orig_sampler =
+         find_sampler(state, orig_binding);
+   char *name;
+
+   asprintf(&name, "%s:%s", orig_sampler->name, ext);
+   new_sampler = nir_variable_create(state->shader, nir_var_uniform,
+                             samplerExternalOES, name);
+   free(name);
+
+   new_sampler->data.binding = new_binding;
+}
+
 static void
 assign_extra_samplers(lower_tex_src_state *state, unsigned free_slots)
 {
@@ -52,12 +80,23 @@ assign_extra_samplers(lower_tex_src_state *state, unsigned free_slots)
    while (mask) {
       unsigned extra, y_samp = u_bit_scan(&mask);
 
-      extra = u_bit_scan(&free_slots);
-      state->sampler_map[y_samp][0] = extra;
-
       if (state->lower_3plane & (1 << y_samp)) {
+         /* two additional planes (U and V): */
+         extra = u_bit_scan(&free_slots);
+         state->sampler_map[y_samp][0] = extra;
+
+         add_sampler(state, y_samp, extra, "u");
+
          extra = u_bit_scan(&free_slots);
          state->sampler_map[y_samp][1] = extra;
+
+         add_sampler(state, y_samp, extra, "v");
+      } else {
+         /* single additional UV plane: */
+         extra = u_bit_scan(&free_slots);
+         state->sampler_map[y_samp][0] = extra;
+
+         add_sampler(state, y_samp, extra, "uv");
       }
    }
 }
@@ -88,7 +127,7 @@ lower_tex_src_plane_block(lower_tex_src_state *state, nir_block *block)
          tex->texture_index = tex->sampler_index =
                state->sampler_map[y_samp][plane[0].i32 - 1];
 
-         state->info->textures_used |= 1u << tex->texture_index;
+         state->shader->info.textures_used |= 1u << tex->texture_index;
       }
 
       nir_tex_instr_remove_src(tex, plane_index);
@@ -112,7 +151,7 @@ st_nir_lower_tex_src_plane(struct nir_shader *shader, unsigned free_slots,
 {
    lower_tex_src_state state = {0};
 
-   state.info = &shader->info;
+   state.shader = shader;
    state.lower_2plane = lower_2plane;
    state.lower_3plane = lower_3plane;