r600g: Add support for relative addressing on constant buffers.

Relative addressing of constant buffers can't work properly through the
kcache, since you can only address within the currently locked kcache window.
Instead, this patch binds the constant buffer as a shader resource, and then
explicitly fetches the constant using a vertex fetch with fetch type
VTX_FETCH_NO_INDEX_OFFSET from the shader. There's probably still some room
for improvement, doing the fetch right before the instruction that needs the
value may not be quite optimal for example.

1 files changed, 4 insertions, 0 deletions

diff --git a/src/gallium/drivers/r600/r600_pipe.h b/src/gallium/drivers/r600/r600_pipe.h
index 5f04fbf0992..b7ea6de3c7c 100644
--- a/src/gallium/drivers/r600/r600_pipe.h
+++ b/src/gallium/drivers/r600/r600_pipe.h
@@ -36,6 +36,8 @@
 #include "r600_shader.h"
 #include "r600_resource.h"
 
+#define R600_MAX_CONST_BUFFERS 1
+
 enum r600_pipe_state_id {
 	R600_PIPE_STATE_BLEND = 0,
 	R600_PIPE_STATE_BLEND_COLOR,
@@ -140,7 +142,9 @@ struct r600_pipe_context {
 	struct r600_pipe_shader 	*ps_shader;
 	struct r600_pipe_shader 	*vs_shader;
 	struct r600_pipe_state		vs_const_buffer;
+	struct r600_pipe_state		vs_const_buffer_resource[R600_MAX_CONST_BUFFERS];
 	struct r600_pipe_state		ps_const_buffer;
+	struct r600_pipe_state		ps_const_buffer_resource[R600_MAX_CONST_BUFFERS];
 	struct r600_pipe_rasterizer	*rasterizer;
 	/* shader information */
 	unsigned			sprite_coord_enable;