gallium: add a cap for max vertex streams

Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Roland Scheidegger <sroland@vmware.com>

src/gallium/docs/source/screen.rst

@@ -205,6 +205,9 @@ The integer capabilities:
 * ``PIPE_CAP_TGSI_VS_WINDOW_SPACE_POSITION``: Whether
   TGSI_PROPERTY_VS_WINDOW_SPACE_POSITION is supported, which disables clipping
   and viewport transformation.
+* ``PIPE_CAP_MAX_VERTEX_STREAMS``: The maximum number of vertex streams
+  supported by the geometry shader. If stream-out is supported, this should be
+  at least 1. If stream-out is not supported, this should be 0.
 
 
 .. _pipe_capf:

src/gallium/drivers/freedreno/freedreno_screen.c

@@ -227,6 +227,7 @@ fd_screen_get_param(struct pipe_screen *pscreen, enum pipe_cap param)
 	/* Geometry shader output, unsupported. */
 	case PIPE_CAP_MAX_GEOMETRY_OUTPUT_VERTICES:
 	case PIPE_CAP_MAX_GEOMETRY_TOTAL_OUTPUT_COMPONENTS:
+	case PIPE_CAP_MAX_VERTEX_STREAMS:
 		return 0;
 
 	/* Texturing. */

src/gallium/drivers/i915/i915_screen.c

@@ -270,6 +270,7 @@ i915_get_param(struct pipe_screen *screen, enum pipe_cap cap)
    /* Geometry shader output, unsupported. */
    case PIPE_CAP_MAX_GEOMETRY_OUTPUT_VERTICES:
    case PIPE_CAP_MAX_GEOMETRY_TOTAL_OUTPUT_COMPONENTS:
+   case PIPE_CAP_MAX_VERTEX_STREAMS:
       return 0;
 
    /* Fragment coordinate conventions. */

src/gallium/drivers/ilo/ilo_screen.c

@@ -375,6 +375,7 @@ ilo_get_param(struct pipe_screen *screen, enum pipe_cap param)
       return ILO_MAX_SO_BINDINGS;
    case PIPE_CAP_MAX_GEOMETRY_OUTPUT_VERTICES:
    case PIPE_CAP_MAX_GEOMETRY_TOTAL_OUTPUT_COMPONENTS:
+   case PIPE_CAP_MAX_VERTEX_STREAMS:
       return 0;
    case PIPE_CAP_STREAM_OUTPUT_PAUSE_RESUME:
       if (is->dev.gen >= ILO_GEN(7))

src/gallium/drivers/llvmpipe/lp_screen.c

@@ -192,6 +192,8 @@ llvmpipe_get_param(struct pipe_screen *screen, enum pipe_cap param)
    case PIPE_CAP_MAX_GEOMETRY_OUTPUT_VERTICES:
    case PIPE_CAP_MAX_GEOMETRY_TOTAL_OUTPUT_COMPONENTS:
       return 1024;
+   case PIPE_CAP_MAX_VERTEX_STREAMS:
+      return 1;
    case PIPE_CAP_STREAM_OUTPUT_PAUSE_RESUME:
       return 1;
    case PIPE_CAP_TGSI_CAN_COMPACT_CONSTANTS:

src/gallium/drivers/nouveau/nv30/nv30_screen.c

@@ -117,6 +117,7 @@ nv30_screen_get_param(struct pipe_screen *pscreen, enum pipe_cap param)
    case PIPE_CAP_MAX_STREAM_OUTPUT_INTERLEAVED_COMPONENTS:
    case PIPE_CAP_MAX_GEOMETRY_OUTPUT_VERTICES:
    case PIPE_CAP_MAX_GEOMETRY_TOTAL_OUTPUT_COMPONENTS:
+   case PIPE_CAP_MAX_VERTEX_STREAMS:
    case PIPE_CAP_TGSI_CAN_COMPACT_CONSTANTS:
    case PIPE_CAP_TEXTURE_BARRIER:
    case PIPE_CAP_SEAMLESS_CUBE_MAP:

src/gallium/drivers/nouveau/nv50/nv50_screen.c

@@ -116,6 +116,8 @@ nv50_screen_get_param(struct pipe_screen *pscreen, enum pipe_cap param)
    case PIPE_CAP_MAX_GEOMETRY_OUTPUT_VERTICES:
    case PIPE_CAP_MAX_GEOMETRY_TOTAL_OUTPUT_COMPONENTS:
       return 1024;
+   case PIPE_CAP_MAX_VERTEX_STREAMS:
+      return 1;
    case PIPE_CAP_CONSTANT_BUFFER_OFFSET_ALIGNMENT:
       return 256;
    case PIPE_CAP_TEXTURE_BUFFER_OFFSET_ALIGNMENT:

src/gallium/drivers/nouveau/nvc0/nvc0_screen.c

@@ -103,6 +103,8 @@ nvc0_screen_get_param(struct pipe_screen *pscreen, enum pipe_cap param)
    case PIPE_CAP_MAX_GEOMETRY_OUTPUT_VERTICES:
    case PIPE_CAP_MAX_GEOMETRY_TOTAL_OUTPUT_COMPONENTS:
       return 1024;
+   case PIPE_CAP_MAX_VERTEX_STREAMS:
+      return 1;
    case PIPE_CAP_CONSTANT_BUFFER_OFFSET_ALIGNMENT:
       return 256;
    case PIPE_CAP_TEXTURE_BUFFER_OFFSET_ALIGNMENT:

src/gallium/drivers/r300/r300_screen.c

@@ -156,6 +156,7 @@ static int r300_get_param(struct pipe_screen* pscreen, enum pipe_cap param)
         case PIPE_CAP_MAX_STREAM_OUTPUT_INTERLEAVED_COMPONENTS:
         case PIPE_CAP_MAX_GEOMETRY_OUTPUT_VERTICES:
         case PIPE_CAP_MAX_GEOMETRY_TOTAL_OUTPUT_COMPONENTS:
+        case PIPE_CAP_MAX_VERTEX_STREAMS:
         case PIPE_CAP_STREAM_OUTPUT_PAUSE_RESUME:
         case PIPE_CAP_FRAGMENT_COLOR_CLAMPED:
         case PIPE_CAP_QUADS_FOLLOW_PROVOKING_VERTEX_CONVENTION:

src/gallium/drivers/r600/r600_pipe.c

@@ -333,6 +333,8 @@ static int r600_get_param(struct pipe_screen* pscreen, enum pipe_cap param)
 		return 1024;
 	case PIPE_CAP_MAX_GEOMETRY_TOTAL_OUTPUT_COMPONENTS:
 		return 16384;
+	case PIPE_CAP_MAX_VERTEX_STREAMS:
+		return 1;
 
 	/* Texturing. */
 	case PIPE_CAP_MAX_TEXTURE_2D_LEVELS:

src/gallium/drivers/radeonsi/si_pipe.c

@@ -271,6 +271,8 @@ static int si_get_param(struct pipe_screen* pscreen, enum pipe_cap param)
 		return 1024;
 	case PIPE_CAP_MAX_GEOMETRY_TOTAL_OUTPUT_COMPONENTS:
 		return 4095;
+	case PIPE_CAP_MAX_VERTEX_STREAMS:
+		return 1;
 
 	/* Texturing. */
 	case PIPE_CAP_MAX_TEXTURE_2D_LEVELS:

src/gallium/drivers/softpipe/sp_screen.c

@@ -120,6 +120,8 @@ softpipe_get_param(struct pipe_screen *screen, enum pipe_cap param)
    case PIPE_CAP_MAX_GEOMETRY_OUTPUT_VERTICES:
    case PIPE_CAP_MAX_GEOMETRY_TOTAL_OUTPUT_COMPONENTS:
       return 1024;
+   case PIPE_CAP_MAX_VERTEX_STREAMS:
+      return 1;
    case PIPE_CAP_PRIMITIVE_RESTART:
       return 1;
    case PIPE_CAP_SHADER_STENCIL_EXPORT:

src/gallium/drivers/svga/svga_screen.c

@@ -255,6 +255,7 @@ svga_get_param(struct pipe_screen *screen, enum pipe_cap param)
    case PIPE_CAP_STREAM_OUTPUT_PAUSE_RESUME:
    case PIPE_CAP_MAX_GEOMETRY_OUTPUT_VERTICES:
    case PIPE_CAP_MAX_GEOMETRY_TOTAL_OUTPUT_COMPONENTS:
+   case PIPE_CAP_MAX_VERTEX_STREAMS:
    case PIPE_CAP_TGSI_CAN_COMPACT_CONSTANTS:
    case PIPE_CAP_VERTEX_BUFFER_OFFSET_4BYTE_ALIGNED_ONLY:
    case PIPE_CAP_VERTEX_BUFFER_STRIDE_4BYTE_ALIGNED_ONLY:

src/gallium/include/pipe/p_defines.h

@@ -558,7 +558,8 @@ enum pipe_cap {
    PIPE_CAP_MAX_TEXTURE_GATHER_OFFSET = 96,
    PIPE_CAP_SAMPLE_SHADING = 97,
    PIPE_CAP_TEXTURE_GATHER_OFFSETS = 98,
-   PIPE_CAP_TGSI_VS_WINDOW_SPACE_POSITION = 99
+   PIPE_CAP_TGSI_VS_WINDOW_SPACE_POSITION = 99,
+   PIPE_CAP_MAX_VERTEX_STREAMS = 100,
 };
 
 #define PIPE_QUIRK_TEXTURE_BORDER_COLOR_SWIZZLE_NV50 (1 << 0)

src/mesa/state_tracker/st_extensions.c

@@ -287,6 +287,11 @@ void st_init_limits(struct st_context *st)
       screen->get_param(screen, PIPE_CAP_MAX_STREAM_OUTPUT_SEPARATE_COMPONENTS);
    c->MaxTransformFeedbackInterleavedComponents =
       screen->get_param(screen, PIPE_CAP_MAX_STREAM_OUTPUT_INTERLEAVED_COMPONENTS);
+   c->MaxVertexStreams =
+      MAX2(1, screen->get_param(screen, PIPE_CAP_MAX_VERTEX_STREAMS));
+
+   /* The vertex stream must fit into pipe_stream_output_info::stream */
+   assert(c->MaxVertexStreams <= 4);
 
    c->StripTextureBorder = GL_TRUE;