[PATCH RFC 1/5] drm/display/dsc: Add flatness and initial scale value calculations

[Jessica Zhang]

On 3/29/2023 4:25 PM, Dmitry Baryshkov wrote:
> On 30/03/2023 02:18, Jessica Zhang wrote:
>> Add helpers to calculate det_thresh_flatness and initial_scale_value as
>> these calculations are defined within the DSC spec.
>>
>> Signed-off-by: Jessica Zhang <quic_jesszhan at quicinc.com>
>> ---
>>   include/drm/display/drm_dsc_helper.h | 10 ++++++++++
>>   1 file changed, 10 insertions(+)
>>
>> diff --git a/include/drm/display/drm_dsc_helper.h 
>> b/include/drm/display/drm_dsc_helper.h
>> index 4448c482b092..63175650a45e 100644
>> --- a/include/drm/display/drm_dsc_helper.h
>> +++ b/include/drm/display/drm_dsc_helper.h
>> @@ -17,6 +17,16 @@ enum drm_dsc_params_kind {
>>       DRM_DSC_1_2_420,
>>   };
>> +static inline int drm_dsc_calculate_initial_scale_value(struct 
>> drm_dsc_config *dsc)
>> +{
>> +    return 8 * dsc->rc_model_size / (dsc->rc_model_size - 
>> dsc->initial_offset);
> 
> Just set this in drm_dsc_config, like other functions do.

Hi Dmitry,

Thanks for the feedback. Acked for both comments here.

Thanks,

Jessica Zhang

> 
>> +}
>> +
>> +static inline int drm_dsc_calculate_det_thresh_flatness(struct 
>> drm_dsc_config *dsc)
>> +{
>> +    return 2 << (dsc->bits_per_component - 8);
>> +}
> 
> this is flatness_det_thresh, per the standard.
> 
> Otherwise LGTM
> 
>> +
>>   void drm_dsc_dp_pps_header_init(struct dp_sdp_header *pps_header);
>>   int drm_dsc_dp_rc_buffer_size(u8 rc_buffer_block_size, u8 
>> rc_buffer_size);
>>   void drm_dsc_pps_payload_pack(struct drm_dsc_picture_parameter_set 
>> *pps_sdp,
>>
> 
> -- 
> With best wishes
> Dmitry
>