fixup the scale calculation formula on the case
src_height == (dst_height/2).

Signed-off-by: Mark Yao <redacted>
---
  drivers/gpu/drm/rockchip/rockchip_drm_vop.h | 3 +++
  1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop.h b/drivers/gpu/drm/rockchip/rockchip_drm_vop.h
index af1091f..56bbd2e 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.h
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.h

@@ -299,6 +299,9 @@ static inline uint16_t scl_get_bili_dn_vskip(int src_h, int dst_h,
  
  	act_height = (src_h + vskiplines - 1) / vskiplines;
  
+	if (act_height == dst_h)
+		return GET_SCL_FT_BILI_DN(src_h, dst_h) / vskiplines;
+
  	return GET_SCL_FT_BILI_DN(act_height, dst_h);
  }