commit 8cf798d253c518de3f4158ee7204136316cfdbb1
author Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com> Thu Oct 08 19:30:44 2020 -0400
committer Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com> Sat Oct 10 17:15:03 2020 -0400
tree c558ddd4fee0fc2fc32f6f2a1de00c45459d9286
parent 7f5428410f231e99ce3e328bdaaa637a93908ac2

pan/bi: Implement FETCH

For texelFetch. A few earlier header fields were wrong.

Fixes dEQP-GLES2.functional.texture.mipmap.2d.generate.rgba8888_fastest

Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7081>

src/panfrost/bifrost/bifrost.h

diff --git a/src/panfrost/bifrost/bifrost.h b/src/panfrost/bifrost/bifrost.h
index 3376022..0592cc0 100644
--- a/src/panfrost/bifrost/bifrost.h
+++ b/src/panfrost/bifrost/bifrost.h
@@ -526,15 +526,15 @@
         /* Texture dimension, or 0 for a cubemap */
         unsigned dimension : 2;
 
-        /* Method to compute LOD value */
-        enum bifrost_lod_mode lod_mode : 3;
+        /* Method to compute LOD value or for a FETCH, the
+         * bifrost_texture_fetch component specification */
+        enum bifrost_lod_mode lod_or_fetch : 3;
 
         /* Reserved */
         unsigned zero : 1;
 
-        /* Register format for the result or for a FETCH, the
-         * bifrost_texture_fetch component specification */
-        enum bifrost_texture_format_full format_or_fetch : 4;
+        /* Register format for the result */
+        enum bifrost_texture_format_full format : 4;
 
         /* Write mask for the result */
         unsigned mask : 4;

src/panfrost/bifrost/bifrost_compile.c

diff --git a/src/panfrost/bifrost/bifrost_compile.c b/src/panfrost/bifrost/bifrost_compile.c
index 79ff7e7..ab12880 100644
--- a/src/panfrost/bifrost/bifrost_compile.c
+++ b/src/panfrost/bifrost/bifrost_compile.c
@@ -1184,6 +1184,7 @@
         case nir_texop_tex:
         case nir_texop_txl:
         case nir_texop_txb:
+        case nir_texop_txf:
                 break;
         default:
                 unreachable("Unsupported texture op");
@@ -1211,11 +1212,22 @@
                 .shadow_or_clamp_disable = instr->is_shadow,
                 .array = false, /* TODO */
                 .dimension = bifrost_tex_format(instr->sampler_dim),
-                .lod_mode = BIFROST_LOD_MODE_COMPUTE,
-                .format_or_fetch = bi_texture_format(instr->dest_type, BIFROST_NONE), /* TODO */
+                .format = bi_texture_format(instr->dest_type, BIFROST_NONE), /* TODO */
                 .mask = (1 << tex.vector_channels) - 1
         };
 
+        switch (desc.op) {
+        case BIFROST_TEX_OP_TEX:
+                desc.lod_or_fetch = BIFROST_LOD_MODE_COMPUTE;
+                break;
+        case BIFROST_TEX_OP_FETCH:
+                /* TODO: gathers */
+                desc.lod_or_fetch = BIFROST_TEXTURE_FETCH_TEXEL;
+                break;
+        default:
+                unreachable("texture op unsupported");
+        }
+
         /* 32-bit indices to be allocated as consecutive data registers. */
         unsigned dregs[BIFROST_TEX_DREG_COUNT] = { 0 };
 
@@ -1235,25 +1247,33 @@
 
                 case nir_tex_src_lod:
                         if (nir_src_is_const(instr->src[i].src) && nir_src_as_uint(instr->src[i].src) == 0) {
-                                desc.lod_mode = BIFROST_LOD_MODE_ZERO;
-                        } else {
+                                desc.lod_or_fetch = BIFROST_LOD_MODE_ZERO;
+                        } else if (desc.op == BIFROST_TEX_OP_TEX) {
                                 assert(base == nir_type_float);
 
                                 assert(sz == 16 || sz == 32);
                                 dregs[BIFROST_TEX_DREG_LOD] =
                                         bi_emit_lod_88(ctx, index, sz == 16);
-                                desc.lod_mode = BIFROST_LOD_MODE_EXPLICIT;
+                                desc.lod_or_fetch = BIFROST_LOD_MODE_EXPLICIT;
+                        } else {
+                                assert(desc.op == BIFROST_TEX_OP_FETCH);
+                                assert(base == nir_type_uint || base == nir_type_int);
+                                assert(sz == 16 || sz == 32);
+
+                                dregs[BIFROST_TEX_DREG_LOD] =
+                                        bi_emit_lod_cube(ctx, index);
                         }
 
                         break;
 
                 case nir_tex_src_bias:
                         /* Upper 16-bits interpreted as a clamp, leave zero */
+                        assert(desc.op == BIFROST_TEX_OP_TEX);
                         assert(base == nir_type_float);
                         assert(sz == 16 || sz == 32);
                         dregs[BIFROST_TEX_DREG_LOD] =
                                 bi_emit_lod_88(ctx, index, sz == 16);
-                        desc.lod_mode = BIFROST_LOD_MODE_BIAS;
+                        desc.lod_or_fetch = BIFROST_LOD_MODE_BIAS;
                         break;
 
                 default: