[PATCH v3] drm/xe/pf: Don't allow LMEM provisioning if LMTT isn't available on the device

[Summers, Stuart]

On Thu, 2025-04-17 at 16:21 +0200, Piórkowski, Piotr wrote:
> From: Piotr Piórkowski <piotr.piorkowski at intel.com>
> 
> The LMEM provisioning is applicable only on platforms with LMTT.
> 
> v2:
>  - new commit description
>  - use xe_gt_assert in xe_gt_sriov_pf_config_set_lmem instead return
>    error,
>  - disable pf_lmem_info if LMTT is not available
> v3: fix condition in xe_gt_assert
> 
> Signed-off-by: Piotr Piórkowski <piotr.piorkowski at intel.com>
> Cc: Michal Wajdeczko <michal.wajdeczko at intel.com>
> ---
>  drivers/gpu/drm/xe/xe_gt_sriov_pf_config.c  | 6 ++++--
>  drivers/gpu/drm/xe/xe_gt_sriov_pf_debugfs.c | 4 ++--
>  2 files changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_gt_sriov_pf_config.c
> b/drivers/gpu/drm/xe/xe_gt_sriov_pf_config.c
> index 2420a548cacc..3556c41c041b 100644
> --- a/drivers/gpu/drm/xe/xe_gt_sriov_pf_config.c
> +++ b/drivers/gpu/drm/xe/xe_gt_sriov_pf_config.c
> @@ -1520,6 +1520,8 @@ int xe_gt_sriov_pf_config_set_lmem(struct xe_gt
> *gt, unsigned int vfid, u64 size
>  {
>         int err;
>  
> +       xe_gt_assert(gt, xe_device_has_lmtt(gt_to_xe(gt)));
> +
>         mutex_lock(xe_gt_sriov_pf_master_mutex(gt));
>         if (vfid)
>                 err = pf_provision_vf_lmem(gt, vfid, size);
> @@ -1629,7 +1631,7 @@ int xe_gt_sriov_pf_config_set_fair_lmem(struct
> xe_gt *gt, unsigned int vfid,
>         xe_gt_assert(gt, num_vfs);
>         xe_gt_assert(gt, !xe_gt_is_media_type(gt));
>  
> -       if (!IS_DGFX(gt_to_xe(gt)))
> +       if (!xe_device_has_lmtt(gt_to_xe(gt)))
>                 return 0;
>  
>         mutex_lock(xe_gt_sriov_pf_master_mutex(gt));
> @@ -2163,7 +2165,7 @@ static int pf_validate_vf_config(struct xe_gt
> *gt, unsigned int vfid)
>         valid_all = valid_all && valid_ggtt;
>         valid_any = valid_any || (valid_ggtt && is_primary);
>  
> -       if (IS_DGFX(xe)) {
> +       if (xe_device_has_lmtt(xe)) {

I see a few other calls like pf_sanitize_vf_resources() and
pf_validate_vf_config() and pf_restore_vf_config_klv() and
pf_get_ggtt_alignment() in this same file. Is there a reason not to
just change all these at once?

Also right now has_lmtt just calls IS_DGFX, and I confirmed this looks
right from the specs, so at a high level:
Reviewed-by: Stuart Summers <stuart.summers at intel.com>

Thanks,
Stuart

>                 bool valid_lmem = pf_get_vf_config_lmem(primary_gt,
> vfid);
>  
>                 valid_any = valid_any || (valid_lmem && is_primary);
> diff --git a/drivers/gpu/drm/xe/xe_gt_sriov_pf_debugfs.c
> b/drivers/gpu/drm/xe/xe_gt_sriov_pf_debugfs.c
> index 0fe47f41b63c..13970d5a2867 100644
> --- a/drivers/gpu/drm/xe/xe_gt_sriov_pf_debugfs.c
> +++ b/drivers/gpu/drm/xe/xe_gt_sriov_pf_debugfs.c
> @@ -308,7 +308,7 @@ static void pf_add_config_attrs(struct xe_gt *gt,
> struct dentry *parent, unsigne
>         if (!xe_gt_is_media_type(gt)) {
>                 debugfs_create_file_unsafe(vfid ? "ggtt_quota" :
> "ggtt_spare",
>                                            0644, parent, parent,
> &ggtt_fops);
> -               if (IS_DGFX(gt_to_xe(gt)))
> +               if (xe_device_has_lmtt(gt_to_xe(gt)))
>                         debugfs_create_file_unsafe(vfid ?
> "lmem_quota" : "lmem_spare",
>                                                    0644, parent,
> parent, &lmem_fops);
>         }
> @@ -558,7 +558,7 @@ void xe_gt_sriov_pf_debugfs_register(struct xe_gt
> *gt, struct dentry *root)
>                 drm_debugfs_create_files(pf_ggtt_info,
>                                          ARRAY_SIZE(pf_ggtt_info),
>                                          pfdentry, minor);
> -               if (IS_DGFX(gt_to_xe(gt)))
> +               if (xe_device_has_lmtt(gt_to_xe(gt)))
>                         drm_debugfs_create_files(pf_lmem_info,
>                                                 
> ARRAY_SIZE(pf_lmem_info),
>                                                  pfdentry, minor);