drm/xe/pf: Add wait helper for VF FLR

VF FLR requires additional processing done by PF driver.
The processing is done after FLR is already finished from PCIe
perspective.
In order to avoid a scenario where migration state transitions while
PF processing is still in progress, additional synchronization
point is needed.
Add a helper that will be used as part of VF driver struct
pci_error_handlers .reset_done() callback.

Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Link: https://patch.msgid.link/20251112132220.516975-24-michal.winiarski@intel.com
Signed-off-by: Michał Winiarski <michal.winiarski@intel.com>

diff --git a/drivers/gpu/drm/xe/xe_sriov_pf_control.c b/drivers/gpu/drm/xe/xe_sriov_pf_control.c
index 86668bd4213e070054ce72c808b87c5ce33cd992..ed4b9820b06e418b5f1a8008eff8045150ce8083 100644 (file)
--- a/drivers/gpu/drm/xe/xe_sriov_pf_control.c
+++ b/drivers/gpu/drm/xe/xe_sriov_pf_control.c
@@ -123,6 +123,30 @@ int xe_sriov_pf_control_reset_vf(struct xe_device *xe, unsigned int vfid)
        return result;
 }
 
+/**
+ * xe_sriov_pf_control_wait_flr() - Wait for a VF reset (FLR) to complete.
+ * @xe: the &xe_device
+ * @vfid: the VF identifier
+ *
+ * This function is for PF only.
+ *
+ * Return: 0 on success or a negative error code on failure.
+ */
+int xe_sriov_pf_control_wait_flr(struct xe_device *xe, unsigned int vfid)
+{
+       struct xe_gt *gt;
+       unsigned int id;
+       int result = 0;
+       int err;
+
+       for_each_gt(gt, xe, id) {
+               err = xe_gt_sriov_pf_control_wait_flr(gt, vfid);
+               result = result ? -EUCLEAN : err;
+       }
+
+       return result;
+}
+
 /**
  * xe_sriov_pf_control_sync_flr() - Synchronize a VF FLR between all GTs.
  * @xe: the &xe_device

diff --git a/drivers/gpu/drm/xe/xe_sriov_pf_control.h b/drivers/gpu/drm/xe/xe_sriov_pf_control.h
index 30318c1fba34e48b7fd314c23baf7233534f568b..ef9f219b210966f5c41a85081b6aed74d9608152 100644 (file)
--- a/drivers/gpu/drm/xe/xe_sriov_pf_control.h
+++ b/drivers/gpu/drm/xe/xe_sriov_pf_control.h
@@ -12,6 +12,7 @@ int xe_sriov_pf_control_pause_vf(struct xe_device *xe, unsigned int vfid);
 int xe_sriov_pf_control_resume_vf(struct xe_device *xe, unsigned int vfid);
 int xe_sriov_pf_control_stop_vf(struct xe_device *xe, unsigned int vfid);
 int xe_sriov_pf_control_reset_vf(struct xe_device *xe, unsigned int vfid);
+int xe_sriov_pf_control_wait_flr(struct xe_device *xe, unsigned int vfid);
 int xe_sriov_pf_control_sync_flr(struct xe_device *xe, unsigned int vfid);
 int xe_sriov_pf_control_trigger_save_vf(struct xe_device *xe, unsigned int vfid);
 int xe_sriov_pf_control_finish_save_vf(struct xe_device *xe, unsigned int vfid);