Re: [PATCH v3 1/1] drm/xe: Set GT rp min frequency as 1.2GHz default for BMG/CRI

["Kumar G, Naresh" <naresh.kumar.g@intel.com>]

On 25-03-2026 02:45, Summers, Stuart wrote:
> On Tue, 2026-03-24 at 23:51 +0530, Nareshkumar Gollakoti wrote:
>>   While previously applied only to both tiles GT0(Graphics) and
>> Media(GT1)
>>   the BMG G21(Battle image) platform via workaround Wa_14022085890,
>>   this 1.2 GHz minimum is now the default for GT0(Graphics) tile
>>   of BMG and CRI platforms.
>>
>>   Setting this frequency floor(1.2GHz) default is critical in multi
>> GPU
>>   environment for supporting effective Peer-to-Peer(P2P) transactions.
>>
>> v2:
>> - Fix Indentation(Thomas)
>> - Add comment about power impact(Stuart)
>>
>> v3:(Thomas/Ankur/Matt Roper)
>> - Add setting frequency to only GT0(Graphics) Tile of BMG/CRI
>>
>> Signed-off-by: Nareshkumar Gollakoti <naresh.kumar.g@intel.com>
>> ---
>>   drivers/gpu/drm/xe/xe_guc_pc.c | 29 ++++++++++++++++++++++++++++-
>>   1 file changed, 28 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/xe/xe_guc_pc.c
>> b/drivers/gpu/drm/xe/xe_guc_pc.c
>> index 5e5495a39a3c..2abfc2fff083 100644
>> --- a/drivers/gpu/drm/xe/xe_guc_pc.c
>> +++ b/drivers/gpu/drm/xe/xe_guc_pc.c
>> @@ -856,6 +856,21 @@ void xe_guc_pc_init_early(struct xe_guc_pc *pc)
>>          pc_init_fused_rp_values(pc);
>>   }
>>   
>> +static bool pc_needs_min_freq_change(struct xe_guc_pc *pc)
>> +{
>> +       struct xe_device *xe = pc_to_xe(pc);
>> +       struct xe_gt *gt = pc_to_gt(pc);
>> +
>> +       if (xe_gt_is_media_type(gt))
>> +               return false;
>> +
>> +       if (xe->info.platform == XE_BATTLEMAGE ||
>> +           xe->info.platform == XE_CRESCENTISLAND)
>> +               return true;
>> +
>> +       return false;
>> +}
>> +
>>   static int pc_adjust_freq_bounds(struct xe_guc_pc *pc)
>>   {
>>          struct xe_tile *tile = gt_to_tile(pc_to_gt(pc));
>> @@ -885,7 +900,19 @@ static int pc_adjust_freq_bounds(struct
>> xe_guc_pc *pc)
>>          if (pc_get_min_freq(pc) > pc->rp0_freq)
>>                  ret = pc_set_min_freq(pc, pc->rp0_freq);
>>   
>> -       if (XE_DEVICE_WA(tile_to_xe(tile), 14022085890))
>> +       /*
>> +        * Setting GT RP min frequency to 1.2GHz by default for
>> +        * GT0(Graphics) Tile of BMG and CRI.
>> +        *
>> +        * While BMG G21 WA will apply min freqeuncy for
> 
> /s/freqeuncy/frequency/

Noted

> 
>> +        * both GT0(Graphics) and GT1(Media) Tile.
>> +        *
>> +        * This is an active frequency, so if the device is idle
>> +        * we aren't expecting high power output across board
> 
> If you post another series, you might add this last sentance also to
> the cover letter. I think it's important for customers to know that it
> only applies while they are running workloads.

Noted

> 
>> +        *
>> +        */
>> +       if (XE_DEVICE_WA(tile_to_xe(tile), 14022085890) ||
> 
> Is there a reason not to move this bug ID check up to
> pc_needs_min_freq_change() also so we just check everything in one
> place?
> 

There wont be any problem, can be moved inside the function and
just return true at first if WA is applicable otherwise only go further.

Thanks,
Naresh

> Thanks,
> Stuart
> 
>> +           pc_needs_min_freq_change(pc))
>>                  ret = pc_set_min_freq(pc, max(BMG_MIN_FREQ,
>> pc_get_min_freq(pc)));
>>   
>>   out:
>