Re: [PATCHv2] drm/i915/display: BMG supports UHBR13.5

[Jani Nikula <jani.nikula@linux.intel.com>]

On Wed, 28 Aug 2024, "Govindapillai, Vinod" <vinod.govindapillai@intel.com> wrote:
> Hi,
>
> Do we need this? There is this patch already https://patchwork.freedesktop.org/patch/592161/

mtl_rates doesn't have 1350000.

BR,
Jani.

>
> Looks like we are supposed to iterate source_rates using "intel_dp->num_source_rates"
>
> If you are keeping this, then may be we need a separate max_rate call for bmg for better clarity?
> Now there is a separate source_rates for bmg but a max_rate using mtl_max_rate()!
>
> BR
> Vinod
>
>
> On Tue, 2024-08-27 at 13:42 +0530, Arun R Murthy wrote:
>> UHBR20 is not supported by battlemage and the maximum link rate
>> supported is UHBR13.5
>> 
>> v2: Replace IS_DGFX with IS_BATTLEMAGE (Jani)
>> 
>> HSD: 16023263677
>> Signed-off-by: Arun R Murthy <arun.r.murthy@intel.com>
>> ---
>>  drivers/gpu/drm/i915/display/intel_dp.c | 13 +++++++++++--
>>  1 file changed, 11 insertions(+), 2 deletions(-)
>> 
>> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
>> index 789c2f78826d..99a365a945ae 100644
>> --- a/drivers/gpu/drm/i915/display/intel_dp.c
>> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
>> @@ -528,6 +528,10 @@ static void
>>  intel_dp_set_source_rates(struct intel_dp *intel_dp)
>>  {
>>         /* The values must be in increasing order */
>> +       static const int bmg_rates[] = {
>> +               162000, 216000, 243000, 270000, 324000, 432000, 540000, 675000,
>> +               810000, 1000000, 1350000,
>> +       };
>>         static const int mtl_rates[] = {
>>                 162000, 216000, 243000, 270000, 324000, 432000, 540000, 675000,
>>                 810000, 1000000, 2000000,
>> @@ -558,8 +562,13 @@ intel_dp_set_source_rates(struct intel_dp *intel_dp)
>>                     intel_dp->source_rates || intel_dp->num_source_rates);
>>  
>>         if (DISPLAY_VER(dev_priv) >= 14) {
>> -               source_rates = mtl_rates;
>> -               size = ARRAY_SIZE(mtl_rates);
>> +               if (IS_BATTLEMAGE(dev_priv)) {
>> +                       source_rates = bmg_rates;
>> +                       size = ARRAY_SIZE(bmg_rates);
>> +               } else {
>> +                       source_rates = mtl_rates;
>> +                       size = ARRAY_SIZE(mtl_rates);
>> +               }
>>                 max_rate = mtl_max_source_rate(intel_dp);
>>         } else if (DISPLAY_VER(dev_priv) >= 11) {
>>                 source_rates = icl_rates;
>

-- 
Jani Nikula, Intel