gallium: Change PIPE_CAP_TGSI_FS_FBFETCH bool to PIPE_CAP_FBFETCH count

TGSI's FBFETCH instruction currently only supports reading from a single
render target, but NIR intrinsics can support multiple render targets.

radeonsi can only support fetching from RT 0, but other drivers may be
able to support fetching from any render target.

To express this, this patch renames PIPE_CAP_TGSI_FS_FBFETCH to simply
PIPE_CAP_FBFETCH, and converts it from a boolean "is FBFETCH supported?"
to an integer number of render targets which can be fetched.

Reviewed-by: Marek Olšák <[email protected]>

20 files changed, 32 insertions, 24 deletions

diff --git a/src/gallium/auxiliary/util/u_screen.c b/src/gallium/auxiliary/util/u_screen.c
index 62a6a24ff24..05ac9be9451 100644
--- a/src/gallium/auxiliary/util/u_screen.c
+++ b/src/gallium/auxiliary/util/u_screen.c
@@ -270,7 +270,7 @@ u_pipe_screen_get_param_defaults(struct pipe_screen *pscreen,
    case PIPE_CAP_GLSL_TESS_LEVELS_AS_INPUTS:
       return 0;
 
-   case PIPE_CAP_TGSI_FS_FBFETCH:
+   case PIPE_CAP_FBFETCH:
    case PIPE_CAP_TGSI_MUL_ZERO_WINS:
    case PIPE_CAP_DOUBLES:
    case PIPE_CAP_INT64:
diff --git a/src/gallium/auxiliary/util/u_tests.c b/src/gallium/auxiliary/util/u_tests.c
index 7b87337bb98..e9cbb464229 100644
--- a/src/gallium/auxiliary/util/u_tests.c
+++ b/src/gallium/auxiliary/util/u_tests.c
@@ -631,7 +631,7 @@ test_texture_barrier(struct pipe_context *ctx, bool use_fbfetch,
       return;
    }
    if (use_fbfetch &&
-       !ctx->screen->get_param(ctx->screen, PIPE_CAP_TGSI_FS_FBFETCH)) {
+       !ctx->screen->get_param(ctx->screen, PIPE_CAP_FBFETCH)) {
       util_report_result_helper(SKIP, name);
       return;
    }
diff --git a/src/gallium/docs/source/screen.rst b/src/gallium/docs/source/screen.rst
index c678ac91527..054939f6887 100644
--- a/src/gallium/docs/source/screen.rst
+++ b/src/gallium/docs/source/screen.rst
@@ -378,8 +378,10 @@ The integer capabilities:
 * ``PIPE_CAP_GLSL_OPTIMIZE_CONSERVATIVELY``: Tell the GLSL compiler to use
   the minimum amount of optimizations just to be able to do all the linking
   and lowering.
-* ``PIPE_CAP_TGSI_FS_FBFETCH``: Whether a fragment shader can use the FBFETCH
-  opcode to retrieve the current value in the framebuffer.
+* ``PIPE_CAP_FBFETCH``: The number of render targets whose value in the
+  current framebuffer can be read in the shader.  0 means framebuffer fetch
+  is not supported.  1 means that only the first render target can be read,
+  and a larger value would mean that multiple render targets are supported.
 * ``PIPE_CAP_TGSI_MUL_ZERO_WINS``: Whether TGSI shaders support the
   ``TGSI_PROPERTY_MUL_ZERO_WINS`` shader property.
 * ``PIPE_CAP_DOUBLES``: Whether double precision floating-point operations
diff --git a/src/gallium/drivers/etnaviv/etnaviv_screen.c b/src/gallium/drivers/etnaviv/etnaviv_screen.c
index ce3147a7011..f245127d2d9 100644
--- a/src/gallium/drivers/etnaviv/etnaviv_screen.c
+++ b/src/gallium/drivers/etnaviv/etnaviv_screen.c
@@ -255,7 +255,7 @@ etna_screen_get_param(struct pipe_screen *pscreen, enum pipe_cap param)
    case PIPE_CAP_STREAM_OUTPUT_INTERLEAVE_BUFFERS:
    case PIPE_CAP_TGSI_CAN_READ_OUTPUTS:
    case PIPE_CAP_GLSL_OPTIMIZE_CONSERVATIVELY:
-   case PIPE_CAP_TGSI_FS_FBFETCH:
+   case PIPE_CAP_FBFETCH:
    case PIPE_CAP_TGSI_MUL_ZERO_WINS:
    case PIPE_CAP_DOUBLES:
    case PIPE_CAP_INT64:
diff --git a/src/gallium/drivers/freedreno/freedreno_screen.c b/src/gallium/drivers/freedreno/freedreno_screen.c
index 0ec0ad996dc..686a930f494 100644
--- a/src/gallium/drivers/freedreno/freedreno_screen.c
+++ b/src/gallium/drivers/freedreno/freedreno_screen.c
@@ -307,7 +307,7 @@ fd_screen_get_param(struct pipe_screen *pscreen, enum pipe_cap param)
 	case PIPE_CAP_FORCE_PERSAMPLE_INTERP:
 		return 0;
 
-	case PIPE_CAP_TGSI_FS_FBFETCH:
+	case PIPE_CAP_FBFETCH:
 		if (fd_device_version(screen->dev) >= FD_VERSION_GMEM_BASE &&
 				is_a6xx(screen))
 			return 1;
diff --git a/src/gallium/drivers/i915/i915_screen.c b/src/gallium/drivers/i915/i915_screen.c
index d95b0696845..5c96a3ca66f 100644
--- a/src/gallium/drivers/i915/i915_screen.c
+++ b/src/gallium/drivers/i915/i915_screen.c
@@ -312,7 +312,7 @@ i915_get_param(struct pipe_screen *screen, enum pipe_cap cap)
    case PIPE_CAP_TGSI_CAN_READ_OUTPUTS:
    case PIPE_CAP_NATIVE_FENCE_FD:
    case PIPE_CAP_GLSL_OPTIMIZE_CONSERVATIVELY:
-   case PIPE_CAP_TGSI_FS_FBFETCH:
+   case PIPE_CAP_FBFETCH:
    case PIPE_CAP_TGSI_MUL_ZERO_WINS:
    case PIPE_CAP_DOUBLES:
    case PIPE_CAP_INT64:
diff --git a/src/gallium/drivers/iris/iris_screen.c b/src/gallium/drivers/iris/iris_screen.c
index 4a62f15fa3f..0435e8826ef 100644
--- a/src/gallium/drivers/iris/iris_screen.c
+++ b/src/gallium/drivers/iris/iris_screen.c
@@ -192,8 +192,9 @@ iris_get_param(struct pipe_screen *pscreen, enum pipe_cap param)
    case PIPE_CAP_INVALIDATE_BUFFER:
    case PIPE_CAP_SURFACE_REINTERPRET_BLOCKS:
       return true;
+   case PIPE_CAP_FBFETCH:
+      return devinfo->gen >= 9 ? BRW_MAX_DRAW_BUFFERS : 0;
    case PIPE_CAP_CONSERVATIVE_RASTER_INNER_COVERAGE:
-   case PIPE_CAP_TGSI_FS_FBFETCH:
    case PIPE_CAP_POST_DEPTH_COVERAGE:
    case PIPE_CAP_SHADER_STENCIL_EXPORT:
    case PIPE_CAP_DEPTH_CLIP_DISABLE_SEPARATE:
diff --git a/src/gallium/drivers/llvmpipe/lp_screen.c b/src/gallium/drivers/llvmpipe/lp_screen.c
index 551d71e00e0..bfe7a378679 100644
--- a/src/gallium/drivers/llvmpipe/lp_screen.c
+++ b/src/gallium/drivers/llvmpipe/lp_screen.c
@@ -348,7 +348,7 @@ llvmpipe_get_param(struct pipe_screen *screen, enum pipe_cap param)
    case PIPE_CAP_TGSI_CAN_READ_OUTPUTS:
    case PIPE_CAP_NATIVE_FENCE_FD:
    case PIPE_CAP_GLSL_OPTIMIZE_CONSERVATIVELY:
-   case PIPE_CAP_TGSI_FS_FBFETCH:
+   case PIPE_CAP_FBFETCH:
    case PIPE_CAP_TGSI_MUL_ZERO_WINS:
    case PIPE_CAP_TGSI_CLOCK:
    case PIPE_CAP_POLYGON_MODE_FILL_RECTANGLE:
diff --git a/src/gallium/drivers/nouveau/nv30/nv30_screen.c b/src/gallium/drivers/nouveau/nv30/nv30_screen.c
index a65e4d57903..0f9ec6673b5 100644
--- a/src/gallium/drivers/nouveau/nv30/nv30_screen.c
+++ b/src/gallium/drivers/nouveau/nv30/nv30_screen.c
@@ -212,7 +212,7 @@ nv30_screen_get_param(struct pipe_screen *pscreen, enum pipe_cap param)
    case PIPE_CAP_TGSI_CAN_READ_OUTPUTS:
    case PIPE_CAP_NATIVE_FENCE_FD:
    case PIPE_CAP_GLSL_OPTIMIZE_CONSERVATIVELY:
-   case PIPE_CAP_TGSI_FS_FBFETCH:
+   case PIPE_CAP_FBFETCH:
    case PIPE_CAP_TGSI_MUL_ZERO_WINS:
    case PIPE_CAP_DOUBLES:
    case PIPE_CAP_INT64:
diff --git a/src/gallium/drivers/nouveau/nv50/nv50_screen.c b/src/gallium/drivers/nouveau/nv50/nv50_screen.c
index e1cf4485ff7..5e14ac2124d 100644
--- a/src/gallium/drivers/nouveau/nv50/nv50_screen.c
+++ b/src/gallium/drivers/nouveau/nv50/nv50_screen.c
@@ -278,7 +278,7 @@ nv50_screen_get_param(struct pipe_screen *pscreen, enum pipe_cap param)
    case PIPE_CAP_TGSI_CAN_READ_OUTPUTS:
    case PIPE_CAP_NATIVE_FENCE_FD:
    case PIPE_CAP_GLSL_OPTIMIZE_CONSERVATIVELY:
-   case PIPE_CAP_TGSI_FS_FBFETCH:
+   case PIPE_CAP_FBFETCH:
    case PIPE_CAP_DOUBLES:
    case PIPE_CAP_INT64:
    case PIPE_CAP_INT64_DIVMOD:
diff --git a/src/gallium/drivers/nouveau/nvc0/nvc0_screen.c b/src/gallium/drivers/nouveau/nvc0/nvc0_screen.c
index 5c2d50ef559..998116fc251 100644
--- a/src/gallium/drivers/nouveau/nvc0/nvc0_screen.c
+++ b/src/gallium/drivers/nouveau/nvc0/nvc0_screen.c
@@ -280,8 +280,8 @@ nvc0_screen_get_param(struct pipe_screen *pscreen, enum pipe_cap param)
       return 1;
    case PIPE_CAP_PREFER_BLIT_BASED_TEXTURE_TRANSFER:
       return nouveau_screen(pscreen)->vram_domain & NOUVEAU_BO_VRAM ? 1 : 0;
-   case PIPE_CAP_TGSI_FS_FBFETCH:
-      return class_3d >= NVE4_3D_CLASS; /* needs testing on fermi */
+   case PIPE_CAP_FBFETCH:
+      return class_3d >= NVE4_3D_CLASS ? 1 : 0; /* needs testing on fermi */
    case PIPE_CAP_SEAMLESS_CUBE_MAP_PER_TEXTURE:
    case PIPE_CAP_TGSI_BALLOT:
       return class_3d >= NVE4_3D_CLASS;
diff --git a/src/gallium/drivers/r300/r300_screen.c b/src/gallium/drivers/r300/r300_screen.c
index 5c1d37eef6c..d26cf901a7b 100644
--- a/src/gallium/drivers/r300/r300_screen.c
+++ b/src/gallium/drivers/r300/r300_screen.c
@@ -229,7 +229,7 @@ static int r300_get_param(struct pipe_screen* pscreen, enum pipe_cap param)
         case PIPE_CAP_TGSI_CAN_READ_OUTPUTS:
         case PIPE_CAP_NATIVE_FENCE_FD:
         case PIPE_CAP_GLSL_OPTIMIZE_CONSERVATIVELY:
-        case PIPE_CAP_TGSI_FS_FBFETCH:
+        case PIPE_CAP_FBFETCH:
         case PIPE_CAP_TGSI_MUL_ZERO_WINS:
         case PIPE_CAP_DOUBLES:
         case PIPE_CAP_INT64:
diff --git a/src/gallium/drivers/r600/r600_pipe.c b/src/gallium/drivers/r600/r600_pipe.c
index 5c915e0f91a..1aa673c0a53 100644
--- a/src/gallium/drivers/r600/r600_pipe.c
+++ b/src/gallium/drivers/r600/r600_pipe.c
@@ -423,7 +423,7 @@ static int r600_get_param(struct pipe_screen* pscreen, enum pipe_cap param)
 	case PIPE_CAP_TGSI_CAN_READ_OUTPUTS:
 	case PIPE_CAP_NATIVE_FENCE_FD:
 	case PIPE_CAP_GLSL_OPTIMIZE_CONSERVATIVELY:
-	case PIPE_CAP_TGSI_FS_FBFETCH:
+	case PIPE_CAP_FBFETCH:
 	case PIPE_CAP_INT64:
 	case PIPE_CAP_INT64_DIVMOD:
 	case PIPE_CAP_TGSI_TEX_TXF_LZ:
diff --git a/src/gallium/drivers/radeonsi/si_get.c b/src/gallium/drivers/radeonsi/si_get.c
index c2dc25b21db..8217c10d9c9 100644
--- a/src/gallium/drivers/radeonsi/si_get.c
+++ b/src/gallium/drivers/radeonsi/si_get.c
@@ -152,7 +152,7 @@ static int si_get_param(struct pipe_screen *pscreen, enum pipe_cap param)
 	case PIPE_CAP_SIGNED_VERTEX_BUFFER_OFFSET:
 	case PIPE_CAP_TGSI_BALLOT:
 	case PIPE_CAP_TGSI_VOTE:
-	case PIPE_CAP_TGSI_FS_FBFETCH:
+	case PIPE_CAP_FBFETCH:
 	case PIPE_CAP_COMPUTE_GRID_INFO_LAST_BLOCK:
 	case PIPE_CAP_IMAGE_LOAD_FORMATTED:
 	case PIPE_CAP_PREFER_COMPUTE_BLIT_FOR_MULTIMEDIA:
diff --git a/src/gallium/drivers/softpipe/sp_screen.c b/src/gallium/drivers/softpipe/sp_screen.c
index b1b777b4755..8e4074ac01a 100644
--- a/src/gallium/drivers/softpipe/sp_screen.c
+++ b/src/gallium/drivers/softpipe/sp_screen.c
@@ -305,7 +305,7 @@ softpipe_get_param(struct pipe_screen *screen, enum pipe_cap param)
    case PIPE_CAP_TGSI_CAN_READ_OUTPUTS:
    case PIPE_CAP_NATIVE_FENCE_FD:
    case PIPE_CAP_GLSL_OPTIMIZE_CONSERVATIVELY:
-   case PIPE_CAP_TGSI_FS_FBFETCH:
+   case PIPE_CAP_FBFETCH:
    case PIPE_CAP_TGSI_MUL_ZERO_WINS:
    case PIPE_CAP_TGSI_CLOCK:
    case PIPE_CAP_POLYGON_MODE_FILL_RECTANGLE:
diff --git a/src/gallium/drivers/svga/svga_screen.c b/src/gallium/drivers/svga/svga_screen.c
index 02c1a99b2db..92f51ebe919 100644
--- a/src/gallium/drivers/svga/svga_screen.c
+++ b/src/gallium/drivers/svga/svga_screen.c
@@ -448,7 +448,7 @@ svga_get_param(struct pipe_screen *screen, enum pipe_cap param)
    case PIPE_CAP_TGSI_ARRAY_COMPONENTS:
    case PIPE_CAP_TGSI_CAN_READ_OUTPUTS:
    case PIPE_CAP_GLSL_OPTIMIZE_CONSERVATIVELY:
-   case PIPE_CAP_TGSI_FS_FBFETCH:
+   case PIPE_CAP_FBFETCH:
    case PIPE_CAP_TGSI_MUL_ZERO_WINS:
    case PIPE_CAP_DOUBLES:
    case PIPE_CAP_INT64:
diff --git a/src/gallium/drivers/swr/swr_screen.cpp b/src/gallium/drivers/swr/swr_screen.cpp
index 2f4ff5cfa2d..63e235c6676 100644
--- a/src/gallium/drivers/swr/swr_screen.cpp
+++ b/src/gallium/drivers/swr/swr_screen.cpp
@@ -331,7 +331,7 @@ swr_get_param(struct pipe_screen *screen, enum pipe_cap param)
    case PIPE_CAP_STREAM_OUTPUT_PAUSE_RESUME:
    case PIPE_CAP_NATIVE_FENCE_FD:
    case PIPE_CAP_GLSL_OPTIMIZE_CONSERVATIVELY:
-   case PIPE_CAP_TGSI_FS_FBFETCH:
+   case PIPE_CAP_FBFETCH:
    case PIPE_CAP_TGSI_MUL_ZERO_WINS:
    case PIPE_CAP_INT64:
    case PIPE_CAP_INT64_DIVMOD:
diff --git a/src/gallium/drivers/virgl/virgl_screen.c b/src/gallium/drivers/virgl/virgl_screen.c
index 66cb6b7a219..2880aa3a4dc 100644
--- a/src/gallium/drivers/virgl/virgl_screen.c
+++ b/src/gallium/drivers/virgl/virgl_screen.c
@@ -246,8 +246,9 @@ virgl_get_param(struct pipe_screen *screen, enum pipe_cap param)
       return vscreen->caps.caps.v2.capability_bits & VIRGL_CAP_FB_NO_ATTACH;
    case PIPE_CAP_ROBUST_BUFFER_ACCESS_BEHAVIOR:
       return vscreen->caps.caps.v2.capability_bits & VIRGL_CAP_ROBUST_BUFFER_ACCESS;
-   case PIPE_CAP_TGSI_FS_FBFETCH:
-      return vscreen->caps.caps.v2.capability_bits & VIRGL_CAP_TGSI_FBFETCH;
+   case PIPE_CAP_FBFETCH:
+      return (vscreen->caps.caps.v2.capability_bits &
+              VIRGL_CAP_TGSI_FBFETCH) ? 1 : 0;
    case PIPE_CAP_TGSI_CLOCK:
       return vscreen->caps.caps.v2.capability_bits & VIRGL_CAP_SHADER_CLOCK;
    case PIPE_CAP_TGSI_ARRAY_COMPONENTS:
diff --git a/src/gallium/include/pipe/p_defines.h b/src/gallium/include/pipe/p_defines.h
index 6041a004fe4..6232547850f 100644
--- a/src/gallium/include/pipe/p_defines.h
+++ b/src/gallium/include/pipe/p_defines.h
@@ -825,7 +825,7 @@ enum pipe_cap
    PIPE_CAP_NATIVE_FENCE_FD,
    PIPE_CAP_GLSL_OPTIMIZE_CONSERVATIVELY,
    PIPE_CAP_GLSL_TESS_LEVELS_AS_INPUTS,
-   PIPE_CAP_TGSI_FS_FBFETCH,
+   PIPE_CAP_FBFETCH,
    PIPE_CAP_TGSI_MUL_ZERO_WINS,
    PIPE_CAP_DOUBLES,
    PIPE_CAP_INT64,
diff --git a/src/mesa/state_tracker/st_extensions.c b/src/mesa/state_tracker/st_extensions.c
index ae0edc5a4d7..98a3490d4df 100644
--- a/src/mesa/state_tracker/st_extensions.c
+++ b/src/mesa/state_tracker/st_extensions.c
@@ -747,8 +747,6 @@ void st_init_extensions(struct pipe_screen *screen,
       { o(ARB_transform_feedback_overflow_query), PIPE_CAP_QUERY_SO_OVERFLOW           },
       { o(ARB_fragment_shader_interlock),    PIPE_CAP_FRAGMENT_SHADER_INTERLOCK        },
 
-      { o(KHR_blend_equation_advanced),      PIPE_CAP_TGSI_FS_FBFETCH                  },
-
       { o(EXT_blend_equation_separate),      PIPE_CAP_BLEND_EQUATION_SEPARATE          },
       { o(EXT_depth_bounds_test),            PIPE_CAP_DEPTH_BOUNDS_TEST                },
       { o(EXT_disjoint_timer_query),         PIPE_CAP_QUERY_TIMESTAMP                  },
@@ -1396,6 +1394,12 @@ void st_init_extensions(struct pipe_screen *screen,
          consts->DisableVaryingPacking = GL_TRUE;
    }
 
+   unsigned max_fb_fetch_rts = screen->get_param(screen, PIPE_CAP_FBFETCH);
+
+   if (max_fb_fetch_rts > 0) {
+      extensions->KHR_blend_equation_advanced = true;
+   }
+
    consts->MaxViewports = screen->get_param(screen, PIPE_CAP_MAX_VIEWPORTS);
    if (consts->MaxViewports >= 16) {
       if (GLSLVersion >= 400) {