Re: [PATCH v12 1/9] drm/display/dsc: Add flatness and initial scale value calculations

[Jessica Zhang <quic_jesszhan@quicinc.com>]

On 5/22/2023 2:37 AM, Jani Nikula wrote:
> On Wed, 17 May 2023, Jessica Zhang <quic_jesszhan@quicinc.com> wrote:
>> Add helpers to calculate det_thresh_flatness and initial_scale_value as
>> these calculations are defined within the DSC spec.
>>
>> Reviewed-by: Marijn Suijten <marijn.suijten@somainline.org>
>> Signed-off-by: Jessica Zhang <quic_jesszhan@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 fc2104415dcb..753b0034eda7 100644
>> --- a/include/drm/display/drm_dsc_helper.h
>> +++ b/include/drm/display/drm_dsc_helper.h
>> @@ -25,5 +25,15 @@ void drm_dsc_set_rc_buf_thresh(struct drm_dsc_config *vdsc_cfg);
>>   int drm_dsc_setup_rc_params(struct drm_dsc_config *vdsc_cfg, enum drm_dsc_params_type type);
>>   int drm_dsc_compute_rc_parameters(struct drm_dsc_config *vdsc_cfg);
>>   
>> +static inline u8 drm_dsc_initial_scale_value(const struct drm_dsc_config *dsc)
>> +{
>> +	return 8 * dsc->rc_model_size / (dsc->rc_model_size - dsc->initial_offset);
>> +}
>> +
>> +static inline u32 drm_dsc_flatness_det_thresh(const struct drm_dsc_config *dsc)
>> +{
>> +	return 2 << (dsc->bits_per_component - 8);
>> +}
> 
> kernel-doc?

Hi Jani,

Sure, I'll add kernel docs for these.

> Maybe make them regular functions instead of static inline?

I was under the impression that smaller/single-line functions were good 
candidates for inlining. However, if you have a strong preference for 
having these as regular functions, I'm ok with that too.

Thanks,

Jessica Zhang

> 
> BR,
> Jani.
> 
>> +
>>   #endif /* _DRM_DSC_HELPER_H_ */
> 
> -- 
> Jani Nikula, Intel Open Source Graphics Center