i965_drv_video: fix mpeg2 decoding on Sandybridge

Signed-off-by: Xiang, Haihao <haihao.xiang@intel.com>

diff --git a/i965_drv_video/gen6_mfd.c b/i965_drv_video/gen6_mfd.c
index c6fab96..71d9944 100644 (file)
--- a/i965_drv_video/gen6_mfd.c
+++ b/i965_drv_video/gen6_mfd.c
@@ -1181,12 +1181,19 @@ gen6_mfd_mpeg2_decode_init(VADriverContextP ctx, struct decode_state *decode_sta
     }
 
     /* reference picture */
-    gen6_mfd_context->reference_surface[0].surface_id = pic_param->forward_reference_picture;
+    obj_surface = SURFACE(pic_param->forward_reference_picture);
 
-    if (pic_param->backward_reference_picture == VA_INVALID_ID)
-        gen6_mfd_context->reference_surface[1].surface_id = pic_param->forward_reference_picture;
+    if (obj_surface && obj_surface->bo)
+        gen6_mfd_context->reference_surface[0].surface_id = pic_param->forward_reference_picture;
     else
+        gen6_mfd_context->reference_surface[0].surface_id = VA_INVALID_ID;
+
+    obj_surface = SURFACE(pic_param->backward_reference_picture);
+
+    if (obj_surface && obj_surface->bo)
         gen6_mfd_context->reference_surface[1].surface_id = pic_param->backward_reference_picture;
+    else
+        gen6_mfd_context->reference_surface[1].surface_id = pic_param->forward_reference_picture;
 
     /* must do so !!! */
     for (i = 2; i < ARRAY_ELEMS(gen6_mfd_context->reference_surface); i++)