drm/xe/pf: Skip VRAM auto-provisioning if already provisioned

In case VF's VRAM provisioning using sysfs is done by the admin
prior to VFs enabling, this provisioning will be lost as PF will
run VRAM auto-provisioning anyway. To avoid that skip this auto-
provisioning if any VF has been already provisioned with VRAM.

To help admin find any mistakes, add diagnostics messages about
which VFs were provisioned with VRAM and which were missed.

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Piotr Piórkowski <piotr.piorkowski@intel.com>
Link: https://patch.msgid.link/20260218205553.3561-10-michal.wajdeczko@intel.com

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 d2a2201440b806be7264b80f63effe4e219bdc27..cba20eb6b36b2cf8c1b0b1c6e831be2551a99cfd 100644 (file)
--- a/drivers/gpu/drm/xe/xe_gt_sriov_pf_config.c
+++ b/drivers/gpu/drm/xe/xe_gt_sriov_pf_config.c
@@ -1922,6 +1922,59 @@ static u64 pf_profile_fair_lmem(struct xe_gt *gt, unsigned int num_vfs)
        return ALIGN_DOWN(fair, alignment);
 }
 
+static void __pf_show_provisioning_lmem(struct xe_gt *gt, unsigned int first_vf,
+                                       unsigned int num_vfs, bool provisioned)
+{
+       unsigned int allvfs = 1 + xe_gt_sriov_pf_get_totalvfs(gt); /* PF plus VFs */
+       unsigned long *bitmap __free(bitmap) = bitmap_zalloc(allvfs, GFP_KERNEL);
+       unsigned int weight;
+       unsigned int n;
+
+       if (!bitmap)
+               return;
+
+       for (n = first_vf; n < first_vf + num_vfs; n++) {
+               if (!!pf_get_vf_config_lmem(gt, VFID(n)) == provisioned)
+                       bitmap_set(bitmap, n, 1);
+       }
+
+       weight = bitmap_weight(bitmap, allvfs);
+       if (!weight)
+               return;
+
+       xe_gt_sriov_info(gt, "VF%s%*pbl %s provisioned with VRAM\n",
+                        weight > 1 ? "s " : "", allvfs, bitmap,
+                        provisioned ? "already" : "not");
+}
+
+static void pf_show_all_provisioned_lmem(struct xe_gt *gt)
+{
+       __pf_show_provisioning_lmem(gt, VFID(1), xe_gt_sriov_pf_get_totalvfs(gt), true);
+}
+
+static void pf_show_unprovisioned_lmem(struct xe_gt *gt, unsigned int first_vf,
+                                      unsigned int num_vfs)
+{
+       __pf_show_provisioning_lmem(gt, first_vf, num_vfs, false);
+}
+
+static bool pf_needs_provision_lmem(struct xe_gt *gt, unsigned int first_vf,
+                                   unsigned int num_vfs)
+{
+       unsigned int vfid;
+
+       for (vfid = first_vf; vfid < first_vf + num_vfs; vfid++) {
+               if (pf_get_vf_config_lmem(gt, vfid)) {
+                       pf_show_all_provisioned_lmem(gt);
+                       pf_show_unprovisioned_lmem(gt, first_vf, num_vfs);
+                       return false;
+               }
+       }
+
+       pf_show_all_provisioned_lmem(gt);
+       return true;
+}
+
 /**
  * xe_gt_sriov_pf_config_set_fair_lmem - Provision many VFs with fair LMEM.
  * @gt: the &xe_gt (can't be media)
@@ -1947,6 +2000,9 @@ int xe_gt_sriov_pf_config_set_fair_lmem(struct xe_gt *gt, unsigned int vfid,
 
        guard(mutex)(xe_gt_sriov_pf_master_mutex(gt));
 
+       if (!pf_needs_provision_lmem(gt, vfid, num_vfs))
+               return 0;
+
        fair = pf_estimate_fair_lmem(gt, num_vfs);
        if (!fair)
                return -ENOSPC;