Re: [PATCH v4 1/1] drm/xe: Set GT rp min frequency as 1.2GHz default for BMG/CRI

["Belgaumkar, Vinay" <vinay.belgaumkar@intel.com>]

On 3/25/2026 11:34 PM, 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
>
> v4:(Stuart)
> - Move WA check to pc_needs_min_freq_change function
>
> Signed-off-by: Nareshkumar Gollakoti <naresh.kumar.g@intel.com>
> ---
>   drivers/gpu/drm/xe/xe_guc_pc.c | 32 ++++++++++++++++++++++++++++++--
>   1 file changed, 30 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/xe/xe_guc_pc.c b/drivers/gpu/drm/xe/xe_guc_pc.c
> index 5e5495a39a3c..f92feee3592d 100644
> --- a/drivers/gpu/drm/xe/xe_guc_pc.c
> +++ b/drivers/gpu/drm/xe/xe_guc_pc.c
> @@ -856,9 +856,26 @@ 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_DEVICE_WA(xe, 14022085890))
> +		return true;
> +
> +	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));
>   	int ret;
>   
>   	lockdep_assert_held(&pc->freq_lock);
> @@ -885,7 +902,18 @@ 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 frequency for
> +	 * 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 (pc_needs_min_freq_change(pc))
>   		ret = pc_set_min_freq(pc, max(BMG_MIN_FREQ, pc_get_min_freq(pc)));

LGTM,

Reviewed-by: Vinay Belgaumkar <vinay.belgaumkar@intel.com>

>   
>   out: