diff --git a/drivers/gpu/drm/nouveau/nv50_sor.c b/drivers/gpu/drm/nouveau/nv50_sor.c
index e31ba312c2ff5414894ff8f4f61954485bd7164c..0c68698f23df7d94b86e0a0a6ceb1a45c7b9bdae 100644
--- a/drivers/gpu/drm/nouveau/nv50_sor.c
+++ b/drivers/gpu/drm/nouveau/nv50_sor.c
@@ -337,6 +337,9 @@ nv50_sor_create(struct drm_device *dev, struct dcb_entry *entry)
 		default:
 			break;
 		}
+
+		if (!nv_encoder->dp.mc_unknown)
+			nv_encoder->dp.mc_unknown = 5;
 	}
 
 	return 0;