| commit | 6e4ae9b0eb23378d993b17967fadd0990a2e8b10 | [log] [tgz] |
|---|---|---|
| author | Marijn Suijten <marijn.suijten@somainline.org> | Tue Apr 06 23:47:25 2021 +0200 |
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | Tue May 11 14:47:29 2021 +0200 |
| tree | 7549e0124e8e16f642c7ebea9c22011649468aff | |
| parent | 79f701ec9efa85bb6c09800d439c9cb8e6002dcb [diff] |
drm/msm/mdp5: Do not multiply vclk line count by 100 [ Upstream commit 377569f82ea8228c421cef4da33e056a900b58ca ] Neither vtotal nor drm_mode_vrefresh contain a value that is premultiplied by 100 making the x100 variable name incorrect and resulting in vclks_line to become 100 times larger than it is supposed to be. The hardware counts 100 clockticks too many before tearcheck, leading to severe panel issues on at least the Sony Xperia lineup. This is likely an artifact from the original MDSS DSI panel driver where the calculation [1] corrected for a premultiplied reference framerate by 100 [2]. It does not appear that the above values were ever premultiplied in the history of the DRM MDP5 driver. With this change applied the value written to the SYNC_CONFIG_VSYNC register is now identical to downstream kernels. [1]: https://source.codeaurora.org/quic/la/kernel/msm-3.18/tree/drivers/video/msm/mdss/mdss_mdp_intf_cmd.c?h=LA.UM.8.6.c26-02400-89xx.0#n288 [2]: https://source.codeaurora.org/quic/la/kernel/msm-3.18/tree/drivers/video/msm/mdss/mdss_dsi_panel.c?h=LA.UM.8.6.c26-02400-89xx.0#n1648 Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org> Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org> Link: https://lore.kernel.org/r/20210406214726.131534-3-marijn.suijten@somainline.org Signed-off-by: Rob Clark <robdclark@chromium.org> Signed-off-by: Sasha Levin <sashal@kernel.org>