Re: [PATCH 18/26] drm/xe/pf: Handle GGTT migration data as part of PF control

Michał Winiarski
2025-10-21T01:16:50Z

On Mon, Oct 13, 2025 at 02:36:56PM +0200, Michal Wajdeczko wrote:
>
>
> On 10/11/2025 9:38 PM, Michał Winiarski wrote:
> > Connect the helpers to allow save and restore of GGTT 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 | 13 ++
> > .../gpu/drm/xe/xe_gt_sriov_pf_control_types.h | 1 +
> > drivers/gpu/drm/xe/xe_gt_sriov_pf_migration.c | 119 ++++++++++++++++++
> > drivers/gpu/drm/xe/xe_gt_sriov_pf_migration.h | 4 +
> > 4 files changed, 137 insertions(+)
> >
> > 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 f73a3bf40037c..a74f6feca4830 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(MIGRATION_DATA_WIP);
> > CASE2STR(SAVE_WIP);
> > CASE2STR(SAVE_DATA_GUC);
> > + CASE2STR(SAVE_DATA_GGTT);
> > CASE2STR(SAVE_FAILED);
> > CASE2STR(SAVED);
> > CASE2STR(RESTORE_WIP);
> > @@ -803,6 +804,7 @@ 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_GGTT);
> > 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);
> > }
> > @@ -843,6 +845,13 @@ static bool pf_handle_vf_save_wip(struct xe_gt *gt, unsigned int vfid)
> > return true;
> > }
> >
> > + if (pf_exit_vf_state(gt, vfid, XE_GT_SRIOV_STATE_SAVE_DATA_GGTT)) {
> > + ret = xe_gt_sriov_pf_migration_ggtt_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);
> > @@ -862,6 +871,8 @@ static bool pf_enter_vf_save_wip(struct xe_gt *gt, unsigned int 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);
> > + if (xe_gt_sriov_pf_migration_ggtt_size(gt, vfid) > 0)
> > + pf_enter_vf_state(gt, vfid, XE_GT_SRIOV_STATE_SAVE_DATA_GGTT);
> > pf_queue_vf(gt, vfid);
> > return true;
> > }
> > @@ -970,6 +981,8 @@ 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_GGTT:
> > + return xe_gt_sriov_pf_migration_ggtt_restore(gt, vfid, data);
> > case XE_SRIOV_MIG_DATA_GUC:
> > return xe_gt_sriov_pf_migration_guc_restore(gt, vfid, data);
> > default:
> > 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 b9787c425d9f6..c94ff0258306a 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
> > @@ -72,6 +72,7 @@ enum xe_gt_sriov_control_bits {
> >
> > XE_GT_SRIOV_STATE_SAVE_WIP,
> > XE_GT_SRIOV_STATE_SAVE_DATA_GUC,
> > + XE_GT_SRIOV_STATE_SAVE_DATA_GGTT,
> > 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 0c10284f0b09a..92ecf47e71bc7 100644
> > --- a/drivers/gpu/drm/xe/xe_gt_sriov_pf_migration.c
> > +++ b/drivers/gpu/drm/xe/xe_gt_sriov_pf_migration.c
> > @@ -7,6 +7,7 @@
> >
> > #include "abi/guc_actions_sriov_abi.h"
> > #include "xe_bo.h"
> > +#include "xe_gt_sriov_pf_config.h"
> > #include "xe_gt_sriov_pf_control.h"
> > #include "xe_gt_sriov_pf_helpers.h"
> > #include "xe_gt_sriov_pf_migration.h"
> > @@ -37,6 +38,117 @@ static void pf_dump_mig_data(struct xe_gt *gt, unsigned int vfid,
> > }
> > }
> >
> > +static int pf_save_vf_ggtt_mig_data(struct xe_gt *gt, unsigned int vfid)
> > +{
> > + struct xe_sriov_pf_migration_data *data;
> > + size_t size;
> > + int ret;
> > +
> > + size = xe_gt_sriov_pf_config_get_ggtt(gt, vfid);
> > + if (size == 0)
> > + return 0;
> > + size = size / XE_PAGE_SIZE * sizeof(u64);
>
> maybe it would be better to avoid reusing the var and have two:
>
> u64 alloc_size = xe_gt_sriov_pf_config_get_ggtt(...);
> u64 pte_size = xe_ggtt_pte_size(alloc_size);

We just need the pte size.

>
> > +
> > + data = xe_sriov_pf_migration_data_alloc(gt_to_xe(gt));
> > + if (!data)
> > + return -ENOMEM;
> > +
> > + ret = xe_sriov_pf_migration_data_init(data, gt->tile->id, gt->info.id,
> > + XE_SRIOV_MIG_DATA_GGTT, 0, size);
> > + if (ret)
> > + goto fail;
> > +
> > + ret = xe_gt_sriov_pf_config_ggtt_save(gt, vfid, data->vaddr, size);
> > + if (ret)
> > + goto fail;
> > +
> > + pf_dump_mig_data(gt, vfid, data);
> > +
> > + ret = xe_gt_sriov_pf_migration_ring_produce(gt, vfid, data);
> > + if (ret)
> > + goto fail;
> > +
> > + return 0;
> > +
> > +fail:
> > + xe_sriov_pf_migration_data_free(data);
> > + xe_gt_sriov_err(gt, "Unable to save VF%u GGTT data (%d)\n", vfid, ret);
>
> use %pe for errors

Ok.

>
> > + return ret;
> > +}
> > +
> > +static int pf_restore_vf_ggtt_mig_data(struct xe_gt *gt, unsigned int vfid,
> > + struct xe_sriov_pf_migration_data *data)
> > +{
> > + size_t size;
> > + int ret;
> > +
> > + size = xe_gt_sriov_pf_config_get_ggtt(gt, vfid) / XE_PAGE_SIZE * sizeof(u64);
> > + if (size != data->hdr.size)
> > + return -EINVAL;
>
> do we need this ?
>
> there seems to be similar check in xe_ggtt_node_load() called by restore() below

I'll remove it.

>
> > +
> > + pf_dump_mig_data(gt, vfid, data);
> > +
> > + ret = xe_gt_sriov_pf_config_ggtt_restore(gt, vfid, data->vaddr, size);
> > + if (ret)
> > + return ret;
> > +
> > + return 0;
> > +}
> > +
> > +/**
> > + * xe_gt_sriov_pf_migration_ggtt_size() - Get the size of VF GGTT migration data.
> > + * @gt: the &struct xe_gt
> > + * @vfid: the VF identifier
> > + *
> > + * This function is for PF only.
> > + *
> > + * Return: size in bytes or a negative error code on failure.
> > + */
> > +ssize_t xe_gt_sriov_pf_migration_ggtt_size(struct xe_gt *gt, unsigned int vfid)
> > +{
> > + if (gt != xe_root_mmio_gt(gt_to_xe(gt)))
> > + return 0;
> > +
> > + return xe_gt_sriov_pf_config_get_ggtt(gt, vfid) / XE_PAGE_SIZE * sizeof(u64);
>
> this conversion logic should be done by xe_ggtt layer helper

I'll add a helper.

> > +}
> > +
> > +/**
> > + * xe_gt_sriov_pf_migration_ggtt_save() - Save VF GGTT migration data.
> > + * @gt: the &struct xe_gt
> > + * @vfid: the VF identifier
>
> since there is assert, probably you should also say: "(can't be 0)"

Ok.

Thanks,
-Michał

>
> > + *
> > + * This function is for PF only.
> > + *
> > + * Return: 0 on success or a negative error code on failure.
> > + */
> > +int xe_gt_sriov_pf_migration_ggtt_save(struct xe_gt *gt, unsigned int vfid)
> > +{
> > + xe_gt_assert(gt, IS_SRIOV_PF(gt_to_xe(gt)));
> > + xe_gt_assert(gt, vfid != PFID);
> > + xe_gt_assert(gt, vfid <= xe_sriov_pf_get_totalvfs(gt_to_xe(gt)));
> > +
> > + return pf_save_vf_ggtt_mig_data(gt, vfid);
> > +}
> > +
> > +/**
> > + * xe_gt_sriov_pf_migration_ggtt_restore() - Restore VF GGTT migration data.
> > + * @gt: the &struct xe_gt
> > + * @vfid: the VF identifier
> > + *
> > + * This function is for PF only.
> > + *
> > + * Return: 0 on success or a negative error code on failure.
> > + */
> > +int xe_gt_sriov_pf_migration_ggtt_restore(struct xe_gt *gt, unsigned int vfid,
> > + struct xe_sriov_pf_migration_data *data)
> > +{
> > + xe_gt_assert(gt, IS_SRIOV_PF(gt_to_xe(gt)));
> > + xe_gt_assert(gt, vfid != PFID);
> > + xe_gt_assert(gt, vfid <= xe_sriov_pf_get_totalvfs(gt_to_xe(gt)));
> > +
> > + return pf_restore_vf_ggtt_mig_data(gt, vfid, data);
> > +}
> > +
> > /* Return: number of dwords saved/restored/required or a negative error code on failure */
> > static int guc_action_vf_save_restore(struct xe_guc *guc, u32 vfid, u32 opcode,
> > u64 addr, u32 ndwords)
> > @@ -290,6 +402,13 @@ ssize_t xe_gt_sriov_pf_migration_size(struct xe_gt *gt, unsigned int vfid)
> > size += sizeof(struct xe_sriov_pf_migration_hdr);
> > total += size;
> >
> > + size = xe_gt_sriov_pf_migration_ggtt_size(gt, vfid);
> > + if (size < 0)
> > + return size;
> > + else if (size > 0)
> > + size += sizeof(struct xe_sriov_pf_migration_hdr);
> > + total += size;
> > +
> > return total;
> > }
> >
> > diff --git a/drivers/gpu/drm/xe/xe_gt_sriov_pf_migration.h b/drivers/gpu/drm/xe/xe_gt_sriov_pf_migration.h
> > index 5df64449232bc..5bb8cba2ea0cb 100644
> > --- a/drivers/gpu/drm/xe/xe_gt_sriov_pf_migration.h
> > +++ b/drivers/gpu/drm/xe/xe_gt_sriov_pf_migration.h
> > @@ -16,6 +16,10 @@ ssize_t xe_gt_sriov_pf_migration_guc_size(struct xe_gt *gt, unsigned int vfid);
> > int xe_gt_sriov_pf_migration_guc_save(struct xe_gt *gt, unsigned int vfid);
> > int xe_gt_sriov_pf_migration_guc_restore(struct xe_gt *gt, unsigned int vfid,
> > struct xe_sriov_pf_migration_data *data);
> > +ssize_t xe_gt_sriov_pf_migration_ggtt_size(struct xe_gt *gt, unsigned int vfid);
> > +int xe_gt_sriov_pf_migration_ggtt_save(struct xe_gt *gt, unsigned int vfid);
> > +int xe_gt_sriov_pf_migration_ggtt_restore(struct xe_gt *gt, unsigned int vfid,
> > + struct xe_sriov_pf_migration_data *data);
> >
> > ssize_t xe_gt_sriov_pf_migration_size(struct xe_gt *gt, unsigned int vfid);
> >
>