[Intel-gfx] [PATCH] drm/i915/display/dsc: Clamp the max DSC input BPP to connector's max bpp

[Jani Nikula]

On Thu, 18 Nov 2021, "Navare, Manasi" <manasi.d.navare at intel.com> wrote:
> @Jani , @Ville, can you take a look at this, this was how the original DSC patches
> clamped the max bpp, but with latest DSC changes looks like this is not
> obeyed anymore and needs to be fixed.

When was this changed?

Fixes: ?

>
> Manasi
>
> On Thu, Nov 11, 2021 at 03:09:49PM -0800, Manasi Navare wrote:
>> Pipe_bpp limits are decided by connectors max bpp as computed in
>> compute_sink_pipe_bpp() before computing link and DSC config.
>> Currently dsc_compute_config() sets the max input bpp only based
>> on DSC Input BPPs supported and max bpc requested for the connector
>> but does not clamp it based on connector's max bpp.
>> This patch fixes that.
>> 
>> Cc: Jani Nikula <jani.nikula at intel.com>
>> Cc: Vandita Kulkarni <vandita.kulkarni at intel.com>
>> Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
>> Signed-off-by: Manasi Navare <manasi.d.navare at intel.com>
>> ---
>>  drivers/gpu/drm/i915/display/intel_dp.c | 1 +
>>  1 file changed, 1 insertion(+)
>> 
>> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
>> index 45373c213d9e..82209d995969 100644
>> --- a/drivers/gpu/drm/i915/display/intel_dp.c
>> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
>> @@ -1400,6 +1400,7 @@ static int intel_dp_dsc_compute_config(struct intel_dp *intel_dp,
>>  		return -EINVAL;
>>  
>>  	pipe_bpp = intel_dp_dsc_compute_bpp(intel_dp, conn_state->max_requested_bpc);
>> +	pipe_bpp = min(pipe_bpp, limits->max_bpp);
>>  
>>  	/* Min Input BPC for ICL+ is 8 */
>>  	if (pipe_bpp < 8 * 3) {
>> -- 
>> 2.19.1
>> 

-- 
Jani Nikula, Intel Open Source Graphics Center