pvr, pco: fragment shader metadata boilerplate code

Signed-off-by: Simon Perretta <simon.perretta@imgtec.com>
Acked-by: Erik Faye-Lund <erik.faye-lund@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/36412>

src/compiler/nir/nir_intrinsics.py

@@ -2738,3 +2738,5 @@ intrinsic("wop_pco")
 
 system_value("face_ccw_pco", 1, bit_sizes=[32])
 system_value("front_face_op_pco", 1, bit_sizes=[32])
+
+system_value("fs_meta_pco", 1, bit_sizes=[32])

src/imagination/pco/pco_data.h

@@ -83,6 +83,8 @@ typedef struct _pco_fs_data {
    /** On-chip input attachment formats. */
    enum pipe_format ia_formats[4];
 
+   pco_range meta;
+
    gl_frag_result z_replicate;
 
    /* Blend options. */
@@ -101,6 +103,9 @@ typedef struct _pco_fs_data {
       bool early_frag;
       bool sample_shading;
    } uses;
+
+   struct {
+   } meta_present;
 } pco_fs_data;
 
 /** PCO compute shader-specific data. */

src/imagination/pco/pco_trans_nir.c

@@ -1381,6 +1381,13 @@ static pco_instr *trans_intr(trans_ctx *tctx, nir_intrinsic_instr *intr)
       instr = trans_load_sysval(tctx, intr, dest);
       break;
 
+   case nir_intrinsic_load_fs_meta_pco:
+      return pco_mov(&tctx->b,
+                     dest,
+                     pco_ref_hwreg(tctx->shader->data.fs.meta.start,
+                                   PCO_REG_CLASS_SHARED));
+      break;
+
    case nir_intrinsic_ddx:
    case nir_intrinsic_ddx_fine:
    case nir_intrinsic_ddx_coarse:

src/imagination/vulkan/pds/pvr_pds.h

@@ -899,6 +899,7 @@ struct pvr_pds_descriptor_set {
 #define PVR_BUFFER_TYPE_POINT_SAMPLER (7)
 #define PVR_BUFFER_TYPE_IA_SAMPLER (8)
 #define PVR_BUFFER_TYPE_FRONT_FACE_OP (9)
+#define PVR_BUFFER_TYPE_FS_META (10)
 #define PVR_BUFFER_TYPE_INVALID (~0)
 
 struct pvr_pds_buffer {

src/imagination/vulkan/pds/pvr_pipeline_pds.c

@@ -1579,7 +1579,8 @@ void pvr_pds_generate_descriptor_upload_program(
       case PVR_BUFFER_TYPE_BLEND_CONSTS:
       case PVR_BUFFER_TYPE_POINT_SAMPLER:
       case PVR_BUFFER_TYPE_IA_SAMPLER:
-      case PVR_BUFFER_TYPE_FRONT_FACE_OP: {
+      case PVR_BUFFER_TYPE_FRONT_FACE_OP:
+      case PVR_BUFFER_TYPE_FS_META: {
          struct pvr_const_map_entry_special_buffer *special_buffer_entry;
 
          special_buffer_entry =

src/imagination/vulkan/pvr_cmd_buffer.c

@@ -3848,6 +3848,25 @@ static VkResult pvr_setup_descriptor_mappings(
             break;
          }
 
+         case PVR_BUFFER_TYPE_FS_META: {
+            uint32_t fs_meta = 0;
+
+            struct pvr_suballoc_bo *fs_meta_bo;
+            result = pvr_cmd_buffer_upload_general(cmd_buffer,
+                                                   &fs_meta,
+                                                   sizeof(fs_meta),
+                                                   &fs_meta_bo);
+
+            if (result != VK_SUCCESS)
+               return result;
+
+            PVR_WRITE(qword_buffer,
+                      fs_meta_bo->dev_addr.addr,
+                      special_buff_entry->const_offset,
+                      pds_info->data_size_in_dwords);
+            break;
+         }
+
          default:
             UNREACHABLE("Unsupported special buffer type.");
          }

src/imagination/vulkan/pvr_pipeline.c

@@ -613,6 +613,14 @@ static VkResult pvr_pds_descriptor_program_create_and_upload(
       };
    }
 
+   if (stage == MESA_SHADER_FRAGMENT && data->fs.meta.count > 0) {
+      program.buffers[program.buffer_count++] = (struct pvr_pds_buffer){
+         .type = PVR_BUFFER_TYPE_FS_META,
+         .size_in_dwords = data->fs.meta.count,
+         .destination = data->fs.meta.start,
+      };
+   }
+
    pds_info->entries_size_in_bytes = const_entries_size_in_bytes;
 
    pvr_pds_generate_descriptor_upload_program(&program, NULL, pds_info);
@@ -1738,6 +1746,8 @@ static void pvr_alloc_vs_varyings(pco_data *data, nir_shader *nir)
 static void pvr_alloc_fs_sysvals(pco_data *data, nir_shader *nir)
 {
    BITSET_DECLARE(system_values_read, SYSTEM_VALUE_MAX);
+   bool has_meta = false;
+
    BITSET_COPY(system_values_read, nir->info.system_values_read);
 
    gl_system_value sys_vals[] = {
@@ -1769,6 +1779,16 @@ static void pvr_alloc_fs_sysvals(pco_data *data, nir_shader *nir)
       BITSET_CLEAR(system_values_read, builtin_sys_vals[u]);
 
    assert(BITSET_IS_EMPTY(system_values_read));
+
+   if (!has_meta)
+      return;
+
+   data->fs.meta = (pco_range){
+      .start = data->common.shareds,
+      .count = 1,
+   };
+
+   ++data->common.shareds;
 }
 
 static void pvr_alloc_fs_varyings(pco_data *data, nir_shader *nir)