Re: [PATCH v4 1/5] msm/drm/dsi: Round up DSC hdisplay calculation

From: Konrad Dybcio
Date: Mon May 22 2023 - 16:52:50 EST




On 22.05.2023 22:44, Marijn Suijten wrote:
> On 2023-05-22 13:30:20, Jessica Zhang wrote:
>> Currently, when compression is enabled, hdisplay is reduced via integer
>> division. This causes issues for modes where the original hdisplay is
>> not a multiple of 3.
>>
>> To fix this, use DIV_ROUND_UP to divide hdisplay.
>>
>> Reviewed-by: Marijn Suijten <marijn.suijten@xxxxxxxxxxxxxx>
>> Suggested-by: Marijn Suijten <marijn.suijten@xxxxxxxxxxxxxx>
>
> Nit: probably these should go in the opposite order. And if they're
> all supposed to be chronological, I think it is:
>
> Suggested-by:
> Fixes:
> Signed-off-by:
> Reviewed-by:
>
> But unsure if that's a hard requirement, or even correct at all.
>
> - Marijn
Or you can rely on b4 to pick that up if it comes from others

Konrad
>
>> Fixes: 08802f515c3cf ("drm/msm/dsi: Add support for DSC configuration")
>> Signed-off-by: Jessica Zhang <quic_jesszhan@xxxxxxxxxxx>
>> ---
>> drivers/gpu/drm/msm/dsi/dsi_host.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c
>> index 9223d7ec5a73..18d38b90eb28 100644
>> --- a/drivers/gpu/drm/msm/dsi/dsi_host.c
>> +++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
>> @@ -952,7 +952,7 @@ static void dsi_timing_setup(struct msm_dsi_host *msm_host, bool is_bonded_dsi)
>> * pulse width same
>> */
>> h_total -= hdisplay;
>> - hdisplay = msm_dsc_get_bytes_per_line(msm_host->dsc) / 3;
>> + hdisplay = DIV_ROUND_UP(msm_dsc_get_bytes_per_line(msm_host->dsc), 3);
>> h_total += hdisplay;
>> ha_end = ha_start + hdisplay;
>> }
>>
>> --
>> 2.40.1
>>