gallium: Create a new PIPE_CAP_TILE_RASTER_ORDER for vc4.

Because vc4 can control the order that tiles are rasterized in, we can use
it to implement overlapping blits using normal drawing and
GL_ARB_texture_barrier, as long as we can tell the kernel what order to
render the tiles in.

This commit introduces the core gallium support, vc4 changes will follow.

v2: Fix on the simulator.
v3: Add the cap (disabled) to other drivers, add rst docs for the cap.
v4: Rebase on PIPE_CAP_TGSI_ANY_REG_AS_ADDRESS
v5: Drop vc4 changes from this commit, for clarity.

Reviewed-by: Nicolai Hähnle <[email protected]> (v3)

2 files changed, 11 insertions, 0 deletions

diff --git a/src/gallium/include/pipe/p_defines.h b/src/gallium/include/pipe/p_defines.h
index 212c4af8f70..11af6c8d0d8 100644
--- a/src/gallium/include/pipe/p_defines.h
+++ b/src/gallium/include/pipe/p_defines.h
@@ -778,6 +778,7 @@ enum pipe_cap
    PIPE_CAP_MEMOBJ,
    PIPE_CAP_LOAD_CONSTBUF,
    PIPE_CAP_TGSI_ANY_REG_AS_ADDRESS,
+   PIPE_CAP_TILE_RASTER_ORDER,
 };
 
 #define PIPE_QUIRK_TEXTURE_BORDER_COLOR_SWIZZLE_NV50 (1 << 0)
diff --git a/src/gallium/include/pipe/p_state.h b/src/gallium/include/pipe/p_state.h
index 86c7751eb18..10bf678652d 100644
--- a/src/gallium/include/pipe/p_state.h
+++ b/src/gallium/include/pipe/p_state.h
@@ -125,6 +125,16 @@ struct pipe_rasterizer_state
    unsigned rasterizer_discard:1;
 
    /**
+    * Exposed by PIPE_CAP_TILE_RASTER_ORDER.  When true,
+    * tile_raster_order_increasing_* indicate the order that the rasterizer
+    * should render tiles, to meet the requirements of
+    * GL_MESA_tile_raster_order.
+    */
+   unsigned tile_raster_order_fixed:1;
+   unsigned tile_raster_order_increasing_x:1;
+   unsigned tile_raster_order_increasing_y:1;
+
+   /**
     * When false, depth clipping is disabled and the depth value will be
     * clamped later at the per-pixel level before depth testing.
     * This depends on PIPE_CAP_DEPTH_CLIP_DISABLE.