Re: [PATCH 16/26] drm/xe/pf: Handle GuC migration data as part of PF control

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

On 10/11/2025 9:38 PM, Michał Winiarski wrote:
> Connect the helpers to allow save and restore of GuC migration data in
> stop_copy / resume device state.
> 
> Signed-off-by: Michał Winiarski <michal.winiarski@intel.com>
> ---
>  drivers/gpu/drm/xe/xe_gt_sriov_pf_control.c   | 28 ++++++++++++++++++-
>  .../gpu/drm/xe/xe_gt_sriov_pf_control_types.h |  1 +
>  drivers/gpu/drm/xe/xe_gt_sriov_pf_migration.c |  8 ++++++
>  3 files changed, 36 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_gt_sriov_pf_control.c b/drivers/gpu/drm/xe/xe_gt_sriov_pf_control.c
> index 6ece775b2e80e..f73a3bf40037c 100644
> --- a/drivers/gpu/drm/xe/xe_gt_sriov_pf_control.c
> +++ b/drivers/gpu/drm/xe/xe_gt_sriov_pf_control.c
> @@ -187,6 +187,7 @@ static const char *control_bit_to_string(enum xe_gt_sriov_control_bits bit)
>  	CASE2STR(PAUSED);
>  	CASE2STR(MIGRATION_DATA_WIP);
>  	CASE2STR(SAVE_WIP);
> +	CASE2STR(SAVE_DATA_GUC);
>  	CASE2STR(SAVE_FAILED);
>  	CASE2STR(SAVED);
>  	CASE2STR(RESTORE_WIP);
> @@ -338,6 +339,7 @@ static void pf_exit_vf_mismatch(struct xe_gt *gt, unsigned int vfid)
>  	pf_exit_vf_state(gt, vfid, XE_GT_SRIOV_STATE_STOP_FAILED);
>  	pf_exit_vf_state(gt, vfid, XE_GT_SRIOV_STATE_PAUSE_FAILED);
>  	pf_exit_vf_state(gt, vfid, XE_GT_SRIOV_STATE_RESUME_FAILED);
> +	pf_exit_vf_state(gt, vfid, XE_GT_SRIOV_STATE_SAVE_FAILED);
>  	pf_exit_vf_state(gt, vfid, XE_GT_SRIOV_STATE_FLR_FAILED);
>  }
>  
> @@ -801,6 +803,7 @@ void xe_gt_sriov_pf_control_vf_data_eof(struct xe_gt *gt, unsigned int vfid)
>  
>  static void pf_exit_vf_save_wip(struct xe_gt *gt, unsigned int vfid)
>  {
> +	pf_escape_vf_state(gt, vfid, XE_GT_SRIOV_STATE_SAVE_DATA_GUC);
>  	pf_exit_vf_state(gt, vfid, XE_GT_SRIOV_STATE_SAVE_WIP);
>  }
>  
> @@ -820,16 +823,35 @@ static void pf_exit_vf_saved(struct xe_gt *gt, unsigned int vfid)
>  	pf_exit_vf_state(gt, vfid, XE_GT_SRIOV_STATE_SAVED);
>  }
>  
> +static void pf_enter_vf_save_failed(struct xe_gt *gt, unsigned int vfid)
> +{
> +	pf_enter_vf_state(gt, vfid, XE_GT_SRIOV_STATE_SAVE_FAILED);
> +	pf_exit_vf_wip(gt, vfid);
> +}
> +
>  static bool pf_handle_vf_save_wip(struct xe_gt *gt, unsigned int vfid)
>  {
> +	int ret;
> +
>  	if (!pf_check_vf_state(gt, vfid, XE_GT_SRIOV_STATE_SAVE_WIP))
>  		return false;
>  
> +	if (pf_exit_vf_state(gt, vfid, XE_GT_SRIOV_STATE_SAVE_DATA_GUC)) {
> +		ret = xe_gt_sriov_pf_migration_guc_save(gt, vfid);
> +		if (ret)
> +			goto err;
> +		return true;
> +	}
> +
>  	xe_gt_sriov_pf_control_vf_data_eof(gt, vfid);
>  	pf_exit_vf_save_wip(gt, vfid);
>  	pf_enter_vf_saved(gt, vfid);
>  
>  	return true;
> +
> +err:
> +	pf_enter_vf_save_failed(gt, vfid);
> +	return false;

return true - as this is an indication that state was processed (not that it was successful or not)

>  }
>  
>  static bool pf_enter_vf_save_wip(struct xe_gt *gt, unsigned int vfid)
> @@ -838,6 +860,8 @@ static bool pf_enter_vf_save_wip(struct xe_gt *gt, unsigned int vfid)
>  		pf_enter_vf_state(gt, vfid, XE_GT_SRIOV_STATE_MIGRATION_DATA_WIP);
>  		pf_exit_vf_restored(gt, vfid);
>  		pf_enter_vf_wip(gt, vfid);
> +		if (xe_gt_sriov_pf_migration_guc_size(gt, vfid) > 0)
> +			pf_enter_vf_state(gt, vfid, XE_GT_SRIOV_STATE_SAVE_DATA_GUC);
>  		pf_queue_vf(gt, vfid);
>  		return true;
>  	}
> @@ -946,6 +970,8 @@ static int pf_handle_vf_restore_data(struct xe_gt *gt, unsigned int vfid,
>  				     struct xe_sriov_pf_migration_data *data)
>  {
>  	switch (data->type) {
> +	case XE_SRIOV_MIG_DATA_GUC:
> +		return xe_gt_sriov_pf_migration_guc_restore(gt, vfid, data);
>  	default:
>  		xe_gt_sriov_notice(gt, "Skipping VF%u invalid data type: %d\n", vfid, data->type);
>  		pf_enter_vf_restore_failed(gt, vfid);
> @@ -996,7 +1022,7 @@ static bool pf_enter_vf_restore_wip(struct xe_gt *gt, unsigned int vfid)
>  		pf_enter_vf_state(gt, vfid, XE_GT_SRIOV_STATE_MIGRATION_DATA_WIP);
>  		pf_exit_vf_saved(gt, vfid);
>  		pf_enter_vf_wip(gt, vfid);
> -		pf_enter_vf_restored(gt, vfid);
> +		pf_queue_vf(gt, vfid);
>  		return true;
>  	}
>  
> diff --git a/drivers/gpu/drm/xe/xe_gt_sriov_pf_control_types.h b/drivers/gpu/drm/xe/xe_gt_sriov_pf_control_types.h
> index 68ec9d1fc3daf..b9787c425d9f6 100644
> --- a/drivers/gpu/drm/xe/xe_gt_sriov_pf_control_types.h
> +++ b/drivers/gpu/drm/xe/xe_gt_sriov_pf_control_types.h
> @@ -71,6 +71,7 @@ enum xe_gt_sriov_control_bits {
>  	XE_GT_SRIOV_STATE_MIGRATION_DATA_WIP,
>  
>  	XE_GT_SRIOV_STATE_SAVE_WIP,
> +	XE_GT_SRIOV_STATE_SAVE_DATA_GUC,
>  	XE_GT_SRIOV_STATE_SAVE_FAILED,
>  	XE_GT_SRIOV_STATE_SAVED,
>  
> diff --git a/drivers/gpu/drm/xe/xe_gt_sriov_pf_migration.c b/drivers/gpu/drm/xe/xe_gt_sriov_pf_migration.c
> index e1031465e65c4..0c10284f0b09a 100644
> --- a/drivers/gpu/drm/xe/xe_gt_sriov_pf_migration.c
> +++ b/drivers/gpu/drm/xe/xe_gt_sriov_pf_migration.c
> @@ -279,9 +279,17 @@ int xe_gt_sriov_pf_migration_guc_restore(struct xe_gt *gt, unsigned int vfid,
>  ssize_t xe_gt_sriov_pf_migration_size(struct xe_gt *gt, unsigned int vfid)
>  {
>  	ssize_t total = 0;
> +	ssize_t size;
>  
>  	xe_gt_assert(gt, IS_SRIOV_PF(gt_to_xe(gt)));
>  
> +	size = xe_gt_sriov_pf_migration_guc_size(gt, vfid);
> +	if (size < 0)
> +		return size;
> +	else if (size > 0)

no need for "else"

and isn't zero GuC state size an error anyway ?

> +		size += sizeof(struct xe_sriov_pf_migration_hdr);
> +	total += size;
> +
>  	return total;
>  }
>