Re: [PATCH v2 15/26] drm/xe/pf: Handle GuC migration data as part of PF control

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

On 10/22/2025 12:41 AM, 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   | 26 +++++++++++++++++--
>  .../gpu/drm/xe/xe_gt_sriov_pf_control_types.h |  2 ++
>  drivers/gpu/drm/xe/xe_gt_sriov_pf_migration.c |  9 ++++++-
>  3 files changed, 34 insertions(+), 3 deletions(-)
> 
> 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 c159f35adcbe7..18f6e3028d4f0 100644
> --- a/drivers/gpu/drm/xe/xe_gt_sriov_pf_control.c
> +++ b/drivers/gpu/drm/xe/xe_gt_sriov_pf_control.c
> @@ -188,6 +188,7 @@ static const char *control_bit_to_string(enum xe_gt_sriov_control_bits bit)
>  	CASE2STR(SAVE_WIP);
>  	CASE2STR(SAVE_PROCESS_DATA);
>  	CASE2STR(SAVE_WAIT_DATA);
> +	CASE2STR(SAVE_DATA_GUC);
>  	CASE2STR(SAVE_DATA_DONE);
>  	CASE2STR(SAVE_FAILED);
>  	CASE2STR(SAVED);
> @@ -343,6 +344,7 @@ 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);

this should be in one of the previous patch

>  	pf_exit_vf_state(gt, vfid, XE_GT_SRIOV_STATE_FLR_FAILED);
>  	pf_exit_vf_state(gt, vfid, XE_GT_SRIOV_STATE_SAVE_FAILED);
>  	pf_exit_vf_state(gt, vfid, XE_GT_SRIOV_STATE_RESTORE_FAILED);
> @@ -824,6 +826,7 @@ 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_PROCESS_DATA);
>  		pf_escape_vf_state(gt, vfid, XE_GT_SRIOV_STATE_SAVE_WAIT_DATA);
> +		pf_escape_vf_state(gt, vfid, XE_GT_SRIOV_STATE_SAVE_DATA_GUC);
>  		pf_escape_vf_state(gt, vfid, XE_GT_SRIOV_STATE_SAVE_DATA_DONE);
>  	}
>  }
> @@ -848,6 +851,16 @@ static void pf_enter_vf_save_failed(struct xe_gt *gt, unsigned int vfid)
>  
>  static int pf_handle_vf_save_data(struct xe_gt *gt, unsigned int vfid)
>  {
> +	int ret;
> +
> +	if (pf_exit_vf_state(gt, vfid, XE_GT_SRIOV_STATE_SAVE_DATA_GUC)) {
> +		xe_gt_assert(gt, xe_gt_sriov_pf_migration_guc_size(gt, vfid) > 0);
> +
> +		ret = xe_gt_sriov_pf_migration_guc_save(gt, vfid);
> +		if (ret)
> +			return ret;
> +	}
> +
>  	return 0;
>  }
>  
> @@ -881,6 +894,7 @@ static bool pf_enter_vf_save_wip(struct xe_gt *gt, unsigned int vfid)
>  {
>  	if (pf_enter_vf_state(gt, vfid, XE_GT_SRIOV_STATE_SAVE_WIP)) {
>  		pf_enter_vf_state(gt, vfid, XE_GT_SRIOV_STATE_SAVE_PROCESS_DATA);
> +		pf_enter_vf_state(gt, vfid, XE_GT_SRIOV_STATE_SAVE_DATA_GUC);
>  		pf_enter_vf_wip(gt, vfid);
>  		pf_queue_vf(gt, vfid);
>  		return true;
> @@ -1046,14 +1060,22 @@ static int
>  pf_handle_vf_restore_data(struct xe_gt *gt, unsigned int vfid)
>  {
>  	struct xe_sriov_migration_data *data = xe_gt_sriov_pf_migration_restore_consume(gt, vfid);
> +	int ret = 0;
>  
>  	xe_gt_assert(gt, data);
>  
> -	xe_gt_sriov_notice(gt, "Skipping VF%u unknown data type: %d\n", vfid, data->type);
> +	switch (data->type) {
> +	case XE_SRIOV_MIGRATION_DATA_TYPE_GUC:
> +		ret = xe_gt_sriov_pf_migration_guc_restore(gt, vfid, data);
> +		break;
> +	default:
> +		xe_gt_sriov_notice(gt, "Skipping VF%u unknown data type: %d\n", vfid, data->type);
> +		break;
> +	}
>  
>  	xe_sriov_migration_data_free(data);
>  
> -	return 0;
> +	return ret;
>  }
>  
>  static bool pf_handle_vf_restore(struct xe_gt *gt, unsigned int vfid)
> 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 35ceb2ff62110..8b951ee8a24fe 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
> @@ -33,6 +33,7 @@
>   * @XE_GT_SRIOV_STATE_SAVE_WIP: indicates that VF save operation is in progress.
>   * @XE_GT_SRIOV_STATE_SAVE_PROCESS_DATA: indicates that VF migration data is being produced.
>   * @XE_GT_SRIOV_STATE_SAVE_WAIT_DATA: indicates that PF awaits for space in migration data ring.
> + * @XE_GT_SRIOV_STATE_SAVE_DATA_GUC: indicates PF needs to save VF GuC migration data.
>   * @XE_GT_SRIOV_STATE_SAVE_DATA_DONE: indicates that all migration data was produced by Xe.
>   * @XE_GT_SRIOV_STATE_SAVE_FAILED: indicates that VF save operation has failed.
>   * @XE_GT_SRIOV_STATE_SAVED: indicates that VF data is saved.
> @@ -76,6 +77,7 @@ enum xe_gt_sriov_control_bits {
>  	XE_GT_SRIOV_STATE_SAVE_WIP,
>  	XE_GT_SRIOV_STATE_SAVE_PROCESS_DATA,
>  	XE_GT_SRIOV_STATE_SAVE_WAIT_DATA,
> +	XE_GT_SRIOV_STATE_SAVE_DATA_GUC,

as DATA_GUC and introduced later DATA_GGTT/MMIO/VRAM are kind of sub-states of PROCESS_DATA,
better to keep them together

	XE_GT_SRIOV_STATE_SAVE_PROCESS_DATA,
	XE_GT_SRIOV_STATE_SAVE_DATA_GUC,
	XE_GT_SRIOV_STATE_SAVE_DATA_GGTT,
	XE_GT_SRIOV_STATE_SAVE_DATA_MMIO,
	XE_GT_SRIOV_STATE_SAVE_DATA_VRAM,
	XE_GT_SRIOV_STATE_SAVE_DATA_DONE,
	XE_GT_SRIOV_STATE_SAVE_WAIT_CONSUME,

and at some point you need to update state diagram to include those DATA states

>  	XE_GT_SRIOV_STATE_SAVE_DATA_DONE,
>  	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 127162e8c66e8..594178fbe36d0 100644
> --- a/drivers/gpu/drm/xe/xe_gt_sriov_pf_migration.c
> +++ b/drivers/gpu/drm/xe/xe_gt_sriov_pf_migration.c
> @@ -279,10 +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)));
>  
> -	/* Nothing to query yet - will be updated once per-GT migration data types are added */
> +	size = xe_gt_sriov_pf_migration_guc_size(gt, vfid);
> +	if (size < 0)
> +		return size;
> +	else if (size > 0)

"else" not needed
> +		size += sizeof(struct xe_sriov_pf_migration_hdr);
> +	total += size;
> +
>  	return total;
>  }
>