[PATCH v3 4/6] drm/xe: Assign GT IDs properly on multi-tile + multi-GT platforms

[Cavitt, Jonathan]

-----Original Message-----
From: Intel-xe <intel-xe-bounces at lists.freedesktop.org> On Behalf Of Matt Roper
Sent: Monday, June 30, 2025 10:35 AM
To: intel-xe at lists.freedesktop.org
Cc: Roper, Matthew D <matthew.d.roper at intel.com>
Subject: [PATCH v3 4/6] drm/xe: Assign GT IDs properly on multi-tile + multi-GT platforms
> 
> Although "multi-tile" and "multiple GTs per tile" are mutually-exclusive
> characteristics on all of our platforms today, this may not always be
> true.  Assign GT IDs according to xe->info.max_gt_per_tile in a way that
> should work even if future platforms have different configurations.
> 
> This patch should not change the behavior of current platforms; it only
> future-proofs for potential future designs.
> 
> Signed-off-by: Matt Roper <matthew.d.roper at intel.com>

LGTM.
Reviewed-by: Jonathan Cavitt <jonathan.cavitt at intel.com>
-Jonathan Cavitt

> ---
>  drivers/gpu/drm/xe/xe_mmio.c |  8 --------
>  drivers/gpu/drm/xe/xe_pci.c  | 14 ++++----------
>  2 files changed, 4 insertions(+), 18 deletions(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_mmio.c b/drivers/gpu/drm/xe/xe_mmio.c
> index 7357458bc0d2..b65d888ee8e4 100644
> --- a/drivers/gpu/drm/xe/xe_mmio.c
> +++ b/drivers/gpu/drm/xe/xe_mmio.c
> @@ -82,14 +82,6 @@ static void mmio_multi_tile_setup(struct xe_device *xe, size_t tile_mmio_size)
>  			drm_info(&xe->drm, "tile_count: %d, reduced_tile_count %d\n",
>  				 xe->info.tile_count, tile_count);
>  			xe->info.tile_count = tile_count;
> -
> -			/*
> -			 * FIXME: Needs some work for standalone media, but
> -			 * should be impossible with multi-tile for now:
> -			 * multi-tile platform with standalone media doesn't
> -			 * exist
> -			 */
> -			xe->info.gt_count = xe->info.tile_count;
>  		}
>  	}
>  
> diff --git a/drivers/gpu/drm/xe/xe_pci.c b/drivers/gpu/drm/xe/xe_pci.c
> index 658bfbddf9a8..bccd81e19bb0 100644
> --- a/drivers/gpu/drm/xe/xe_pci.c
> +++ b/drivers/gpu/drm/xe/xe_pci.c
> @@ -694,10 +694,11 @@ static int xe_info_init(struct xe_device *xe,
>  	 */
>  	for_each_tile(tile, xe, id) {
>  		gt = tile->primary_gt;
> -		gt->info.id = xe->info.gt_count++;
>  		gt->info.type = XE_GT_TYPE_MAIN;
> +		gt->info.id = tile->id * xe->info.max_gt_per_tile;
>  		gt->info.has_indirect_ring_state = graphics_desc->has_indirect_ring_state;
>  		gt->info.engine_mask = graphics_desc->hw_engine_mask;
> +		xe->info.gt_count++;
>  
>  		if (MEDIA_VER(xe) < 13 && media_desc)
>  			gt->info.engine_mask |= media_desc->hw_engine_mask;
> @@ -715,17 +716,10 @@ static int xe_info_init(struct xe_device *xe,
>  
>  		gt = tile->media_gt;
>  		gt->info.type = XE_GT_TYPE_MEDIA;
> +		gt->info.id = tile->id * xe->info.max_gt_per_tile + 1;
>  		gt->info.has_indirect_ring_state = media_desc->has_indirect_ring_state;
>  		gt->info.engine_mask = media_desc->hw_engine_mask;
> -
> -		/*
> -		 * FIXME: At the moment multi-tile and standalone media are
> -		 * mutually exclusive on current platforms.  We'll need to
> -		 * come up with a better way to number GTs if we ever wind
> -		 * up with platforms that support both together.
> -		 */
> -		drm_WARN_ON(&xe->drm, id != 0);
> -		gt->info.id = xe->info.gt_count++;
> +		xe->info.gt_count++;
>  	}
>  
>  	return 0;
> -- 
> 2.49.0
> 
>