Just as the function ipu_dmfc_config_wait4eot() tells, the DMFC wait4eot bit
depends on the number of DMFC slots to be used, so it should be called after
the slots are determined in the function ipu_dmfc_alloc_bandwidth().
Based on tests, this patch may eliminate display distortion issue on overlay
plane with small resolutions.  To reproduce the issue, we may run this drm
modetest case - 'modetest -P 19:64x64'.

Signed-off-by: Liu Ying <gnuiyl at gmail.com>
---
 drivers/gpu/drm/imx/ipuv3-plane.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/imx/ipuv3-plane.c 
b/drivers/gpu/drm/imx/ipuv3-plane.c
index cab8a45..afec9f6 100644
--- a/drivers/gpu/drm/imx/ipuv3-plane.c
+++ b/drivers/gpu/drm/imx/ipuv3-plane.c
@@ -200,8 +200,6 @@ int ipu_plane_mode_set(struct ipu_plane *ipu_plane, struct 
drm_crtc *crtc,
                }
        }

-       ipu_dmfc_config_wait4eot(ipu_plane->dmfc, crtc_w);
-
        ret = ipu_dmfc_alloc_bandwidth(ipu_plane->dmfc,
                        calc_bandwidth(crtc_w, crtc_h,
                                       calc_vref(mode)), 64);
@@ -210,6 +208,8 @@ int ipu_plane_mode_set(struct ipu_plane *ipu_plane, struct 
drm_crtc *crtc,
                return ret;
        }

+       ipu_dmfc_config_wait4eot(ipu_plane->dmfc, crtc_w);
+
        ipu_cpmem_zero(ipu_plane->ipu_ch);
        ipu_cpmem_set_resolution(ipu_plane->ipu_ch, src_w, src_h);
        ret = ipu_cpmem_set_fmt(ipu_plane->ipu_ch, fb->pixel_format);
-- 
2.5.0

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