i965/gen6/gs: implement GS_OPCODE_SVB_WRITE opcode

This opcode will be used when sending SVB WRITE messages to save
transform feedback outputs into Streamed Vertex Buffers.

Signed-off-by: Samuel Iglesias Gonsalvez <siglesias@igalia.com>
Acked-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/src/mesa/drivers/dri/i965/brw_defines.h b/src/mesa/drivers/dri/i965/brw_defines.h
index e359c4509b7..1fe4bb57c5a 100644
--- a/src/mesa/drivers/dri/i965/brw_defines.h
+++ b/src/mesa/drivers/dri/i965/brw_defines.h
@@ -1043,6 +1043,18 @@ enum opcode {
     * - dst is the GRF where PrimitiveID information will be moved.
     */
    GS_OPCODE_SET_PRIMITIVE_ID,
+
+   /**
+    * Write transform feedback data to the SVB by sending a SVB WRITE message.
+    * Used in gen6.
+    *
+    * - dst is the MRF register containing the message header.
+    *
+    * - src0 is the register where the vertex data is going to be copied from.
+    *
+    * - src1 is the destination register when write commit occurs.
+    */
+   GS_OPCODE_SVB_WRITE,
 };
 
 enum brw_derivative_quality {