drm/xe: make change ccs_mode a synchronous action

If ccs_mode is being modified via
   /sys/class/drm/cardX/device/tileY/gtY/ccs_mode
the asynchronous reset is triggered and the write returns immediately.

With that some test receive false information about number of CCS engines
or even fail if they proceed without delay after changing the ccs_mode.

Changing the ccs_mode change from async to sync to prevent failures in
tests.

Signed-off-by: Maciej Patelczyk <[email protected]>
Reviewed-by: Lucas De Marchi <[email protected]>
Fixes: f3bc5bb ("drm/xe: Allow userspace to configure CCS mode")
Reviewed-by: Nirmoy Das <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]
Signed-off-by: Nirmoy Das <[email protected]>
(cherry picked from commit 480fb98)
Signed-off-by: Thomas Hellström <[email protected]>

Author: mpatelcz

drivers/gpu/drm/xe/xe_gt_ccs_mode.c

@@ -150,7 +150,7 @@ ccs_mode_store(struct device *kdev, struct device_attribute *attr,
 		xe_gt_info(gt, "Setting compute mode to %d\n", num_engines);
 		gt->ccs_mode = num_engines;
 		xe_gt_record_user_engines(gt);
-		xe_gt_reset_async(gt);
+		xe_gt_reset(gt);
 	}
 
 	mutex_unlock(&xe->drm.filelist_mutex);