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, 26 insertions, 2 deletions

diff --git a/src/gallium/drivers/r600/r600_state_common.c b/src/gallium/drivers/r600/r600_state_common.c
index a2b2c17e2e..bcaf2b9e45 100644
--- a/src/gallium/drivers/r600/r600_state_common.c
+++ b/src/gallium/drivers/r600/r600_state_common.c
@@ -317,6 +317,7 @@ void r600_set_constant_buffer(struct pipe_context *ctx, uint shader, uint index,
 {
 	struct r600_pipe_context *rctx = (struct r600_pipe_context *)ctx;
 	struct r600_resource_buffer *rbuffer = r600_buffer(buffer);
+	struct r600_pipe_state *rstate;
 	uint32_t offset;
 
 	/* Note that the state tracker can unbind constant buffers by
@@ -327,6 +328,7 @@ void r600_set_constant_buffer(struct pipe_context *ctx, uint shader, uint index,
 	}
 
 	r600_upload_const_buffer(rctx, &rbuffer, &offset);
+	offset += r600_bo_offset(rbuffer->r.bo);
 
 	switch (shader) {
 	case PIPE_SHADER_VERTEX:
@@ -337,8 +339,19 @@ void r600_set_constant_buffer(struct pipe_context *ctx, uint shader, uint index,
 					0xFFFFFFFF, NULL);
 		r600_pipe_state_add_reg(&rctx->vs_const_buffer,
 					R_028980_ALU_CONST_CACHE_VS_0,
-					(r600_bo_offset(rbuffer->r.bo) + offset) >> 8, 0xFFFFFFFF, rbuffer->r.bo);
+					offset >> 8, 0xFFFFFFFF, rbuffer->r.bo);
 		r600_context_pipe_state_set(&rctx->ctx, &rctx->vs_const_buffer);
+
+		rstate = &rctx->vs_const_buffer_resource[index];
+		rstate->id = R600_PIPE_STATE_RESOURCE;
+		rstate->nregs = 0;
+		if (rctx->family >= CHIP_CEDAR) {
+			evergreen_pipe_set_buffer_resource(rctx, rstate, &rbuffer->r, offset, 16);
+			evergreen_context_pipe_state_set_vs_resource(&rctx->ctx, rstate, index);
+		} else {
+			r600_pipe_set_buffer_resource(rctx, rstate, &rbuffer->r, offset, 16);
+			r600_context_pipe_state_set_vs_resource(&rctx->ctx, rstate, index);
+		}
 		break;
 	case PIPE_SHADER_FRAGMENT:
 		rctx->ps_const_buffer.nregs = 0;
@@ -348,8 +361,19 @@ void r600_set_constant_buffer(struct pipe_context *ctx, uint shader, uint index,
 					0xFFFFFFFF, NULL);
 		r600_pipe_state_add_reg(&rctx->ps_const_buffer,
 					R_028940_ALU_CONST_CACHE_PS_0,
-					(r600_bo_offset(rbuffer->r.bo) + offset) >> 8, 0xFFFFFFFF, rbuffer->r.bo);
+					offset >> 8, 0xFFFFFFFF, rbuffer->r.bo);
 		r600_context_pipe_state_set(&rctx->ctx, &rctx->ps_const_buffer);
+
+		rstate = &rctx->ps_const_buffer_resource[index];
+		rstate->id = R600_PIPE_STATE_RESOURCE;
+		rstate->nregs = 0;
+		if (rctx->family >= CHIP_CEDAR) {
+			evergreen_pipe_set_buffer_resource(rctx, rstate, &rbuffer->r, offset, 16);
+			evergreen_context_pipe_state_set_ps_resource(&rctx->ctx, rstate, index);
+		} else {
+			r600_pipe_set_buffer_resource(rctx, rstate, &rbuffer->r, offset, 16);
+			r600_context_pipe_state_set_ps_resource(&rctx->ctx, rstate, index);
+		}
 		break;
 	default:
 		R600_ERR("unsupported %d\n", shader);