drm/xe/xe_gt_debugfs: Add synchronous gt reset debugfs

We currently have debugfs support that allows the userspace to initiate
an asynchronous gt reset on command.  However, userspace may also wish
to wait for the completion of the gt reset before performing any
additional work.  To that end, add a version of the force_reset gt
debugfs function that operates synchronously.

Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/1068
Suggested-by: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: Jonathan Cavitt <jonathan.cavitt@intel.com>
CC: John Harrison <john.c.harrison@intel.com>
CC: Stuart Summers <stuart.summers@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240605150828.2736396-1-jonathan.cavitt@intel.com
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

drivers/gpu/drm/xe/xe_gt_debugfs.c

@@ -116,6 +116,17 @@ static int force_reset(struct xe_gt *gt, struct drm_printer *p)
 	return 0;
 }
 
+static int force_reset_sync(struct xe_gt *gt, struct drm_printer *p)
+{
+	xe_pm_runtime_get(gt_to_xe(gt));
+	xe_gt_reset_async(gt);
+	xe_pm_runtime_put(gt_to_xe(gt));
+
+	flush_work(&gt->reset.worker);
+
+	return 0;
+}
+
 static int sa_info(struct xe_gt *gt, struct drm_printer *p)
 {
 	struct xe_tile *tile = gt_to_tile(gt);
@@ -261,6 +272,7 @@ static int vecs_default_lrc(struct xe_gt *gt, struct drm_printer *p)
 static const struct drm_info_list debugfs_list[] = {
 	{"hw_engines", .show = xe_gt_debugfs_simple_show, .data = hw_engines},
 	{"force_reset", .show = xe_gt_debugfs_simple_show, .data = force_reset},
+	{"force_reset_sync", .show = xe_gt_debugfs_simple_show, .data = force_reset_sync},
 	{"sa_info", .show = xe_gt_debugfs_simple_show, .data = sa_info},
 	{"topology", .show = xe_gt_debugfs_simple_show, .data = topology},
 	{"steering", .show = xe_gt_debugfs_simple_show, .data = steering},