Re: [PATCH v5 1/3] drm/xe/vf: Enable VF migration only on supported GuC versions

[Michal Wajdeczko <michal.wajdeczko@intel.com>]

On 11/20/2025 3:51 PM, Satyanarayana K V P wrote:
> Enable VF migration starting with GuC 70.54.0 (compatibility version
> 1.27.0).

this is only says "what", for the "why" part we likely want to add:

" ... which supports additional VF2GUC_RESFIX_START message required
to handle migration recovery in a more robust way."

> 
> Signed-off-by: Satyanarayana K V P <satyanarayana.k.v.p@intel.com>
> Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
> Cc: Matthew Brost <matthew.brost@intel.com>
> Cc: Tomasz Lis <tomasz.lis@intel.com>
> 
> ---
> V4 -> V5:
> - Created new function vf_migration_init_late() (Michal W).
> 
> V3 -> V4:
> - New commit
> 
> V2 -> V3:
> - None.
> 
> V1 -> V2:
> - None.
> ---
>  drivers/gpu/drm/xe/xe_sriov_vf.c | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
> 
> diff --git a/drivers/gpu/drm/xe/xe_sriov_vf.c b/drivers/gpu/drm/xe/xe_sriov_vf.c
> index 284ce37ca92d..13cacdbbf2d2 100644
> --- a/drivers/gpu/drm/xe/xe_sriov_vf.c
> +++ b/drivers/gpu/drm/xe/xe_sriov_vf.c
> @@ -170,6 +170,20 @@ void xe_sriov_vf_init_early(struct xe_device *xe)
>  	vf_migration_init_early(xe);
>  }
>  
> +static void vf_migration_init_late(struct xe_device *xe)
> +{
> +	struct xe_gt *gt = xe_root_mmio_gt(xe);
> +	struct xe_uc_fw_version guc_version;

maybe we should call xe_sriov_vf_migration_supported() too?

> +
> +	xe_gt_sriov_vf_guc_versions(gt, NULL, &guc_version);
> +	if (MAKE_GUC_VER_STRUCT(guc_version) < MAKE_GUC_VER(1, 27, 0)) {
> +		xe_sriov_vf_migration_disable(xe,
> +					      "requires GUC ABI >= 1.27.0, but only %u.%u.%u found",

s/GUC/GuC

> +					      guc_version.major, guc_version.minor,
> +					      guc_version.patch);
> +	}

and return bool/true only if we still claim support for migration?

> +}
> +
>  /**
>   * xe_sriov_vf_init_late() - SR-IOV VF late initialization functions.
>   * @xe: the &xe_device to initialize
> @@ -180,6 +194,7 @@ void xe_sriov_vf_init_early(struct xe_device *xe)
>   */
>  int xe_sriov_vf_init_late(struct xe_device *xe)
>  {
> +	vf_migration_init_late(xe);

then here we can have:

	if (!vf_migration_init_late(xe))
		return 0;

>  	return xe_sriov_vf_ccs_init(xe);
>  }
>