drm/rockchip: vop: init mcu_frame_st as 0 in vop_mcu_mode()

If mcu_hold_mode is 1, set 1 to mcu_frame_st will
refresh one frame from ddr. So mcu_frame_st is needed
to be initialized as 0.

Signed-off-by: Damon Ding <damon.ding@rock-chips.com>
Change-Id: I75d755826dbbdd229da3c3db15d4682dc2bd13a0

drivers/gpu/drm/rockchip/rockchip_drm_vop.c

@@ -3262,6 +3262,12 @@ static void vop_mcu_mode(struct drm_crtc *crtc)
 {
 	struct vop *vop = to_vop(crtc);
 
+	/*
+	 * If mcu_hold_mode is 1, set 1 to mcu_frame_st will
+	 * refresh one frame from ddr. So mcu_frame_st is needed
+	 * to be initialized as 0.
+	 */
+	VOP_CTRL_SET(vop, mcu_frame_st, 0);
 	VOP_CTRL_SET(vop, mcu_clk_sel, 1);
 	VOP_CTRL_SET(vop, mcu_type, 1);