mesa/st: support lowering multi-planar YUV

Support multi-planar YUV for external EGLImage's (currently just in the
dma-buf import path) by lowering to multiple texture fetch's for each
plane and CSC in shader.

There was some discussion of alternative approaches for tracking the
additional UV or U/V planes:

  https://lists.freedesktop.org/archives/mesa-dev/2016-September/127832.html

They all seemed worse than pipe_resource::next

Signed-off-by: Rob Clark <[email protected]>

1 files changed, 21 insertions, 0 deletions

diff --git a/src/mesa/state_tracker/st_texture.h b/src/mesa/state_tracker/st_texture.h
index b2ddc14ddfc..d2c4f3f880c 100644
--- a/src/mesa/state_tracker/st_texture.h
+++ b/src/mesa/state_tracker/st_texture.h
@@ -170,6 +170,27 @@ st_create_texture_sampler_view(struct pipe_context *pipe,
                                                 texture->format);
 }
 
+static inline struct st_texture_object *
+st_get_texture_object(struct gl_context *ctx,
+                      const struct gl_program *prog,
+                      unsigned unit)
+{
+   const GLuint texUnit = prog->SamplerUnits[unit];
+   struct gl_texture_object *texObj = ctx->Texture.Unit[texUnit]._Current;
+
+   if (!texObj)
+      return NULL;
+
+   return st_texture_object(texObj);
+}
+
+static inline enum pipe_format
+st_get_view_format(struct st_texture_object *stObj)
+{
+   if (!stObj)
+      return PIPE_FORMAT_NONE;
+   return stObj->surface_based ? stObj->surface_format : stObj->pt->format;
+}
 
 
 extern struct pipe_resource *