[PATCH v6 6/7] drm/msm/dsi: update hdisplay calculation for dsi_timing_setup

Jessica Zhang quic_jesszhan at quicinc.com
Tue May 9 00:39:16 UTC 2023



On 5/8/2023 2:46 PM, Marijn Suijten wrote:
> On 2023-04-12 16:25:20, Jessica Zhang wrote:
>> hdisplay for compressed images should be calculated as bytes_per_slice *
>> slice_count. Thus, use MSM DSC helper to calculate hdisplay for
>> dsi_timing_setup instead of directly using mode->hdisplay.
> 
> This doesn't really matter in the common case of of bpp=8, as the number
> of horizontal pixels is equal to the number of horizontal slices times
> the width of one horizontal slice.
> 
>> Changes in v3:
>> - Split from previous patch
>> - Initialized hdisplay as uncompressed pclk per line at the beginning of
>>    dsi_timing_setup as to not break dual DSI calculations
>>
>> Changes in v4:
>> - Moved pclk_per_intf calculations to DSC hdisplay adjustments
>>
>> Signed-off-by: Jessica Zhang <quic_jesszhan at quicinc.com>
>> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov at linaro.org>
>> ---
>>   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 508577c596ff..ae966d4e349d 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 /= 3;
>> +		hdisplay = msm_dsc_get_pclk_per_intf(msm_host->dsc) / 3;
> 
> This function sounds like it returns bytes_per_line instead, not the
> number of pixels in case bpp!=8.  Should we rename it?

Hi Marijn,

Sounds good.

Thanks,

Jessica Zhang

> 
> - Marijn
> 
>>   		h_total += hdisplay;
>>   		ha_end = ha_start + hdisplay;
>>   	}
>>
>> -- 
>> 2.40.0
>>


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