diff --git a/drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c b/drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c
index 03c695fc4310..256dfcbe83e0 100644
--- a/drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c
+++ b/drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c
@@ -2450,7 +2450,7 @@ dw_hdmi_rockchip_select_output(struct drm_connector_state *conn_state,
 		DRM_MODE_FLAG_3D_FRAME_PACKING)
 		pixclock *= 2;
 
-	if (hdmi->is_hdmi_qp && mode.clock > 1188000)
+	if ((hdmi->is_hdmi_qp && mode.clock > 1188000) || drm_mode_is_420_only(info, &mode))
 		*color_format = RK_IF_FORMAT_YCBCR420;
 
 	if (!sink_is_hdmi) {