drm/xe/display: Make display suspend/resume work on discrete

We should unpin before evicting all memory, and repin after GT resume.
This way, we preserve the contents of the framebuffers, and won't hang
on resume due to migration engine not being restored yet.

Signed-off-by: Maarten Lankhorst <[e-mail]>
Fixes: dd08ebf6c352 ("drm/xe: Introduce a new DRM driver for Intel GPUs")
Cc: [e-mail] # v6.8+
Reviewed-by: Uma Shankar <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]
Signed-off-by: Maarten Lankhorst,,, <[e-mail]>
(cherry picked from commit cb8f81c1753187995b7a43e79c12959f14eb32d3)
Signed-off-by: Rodrigo Vivi <[e-mail]>

drivers/gpu/drm/xe/display/xe_display.c

···
 	return false;
 }
 
+static void xe_display_flush_cleanup_work(struct xe_device *xe)
+{
+	struct intel_crtc *crtc;
+
+	for_each_intel_crtc(&xe->drm, crtc) {
+		struct drm_crtc_commit *commit;
+
+		spin_lock(&crtc->base.commit_lock);
+		commit = list_first_entry_or_null(&crtc->base.commit_list,
+						  struct drm_crtc_commit, commit_entry);
+		if (commit)
+			drm_crtc_commit_get(commit);
+		spin_unlock(&crtc->base.commit_lock);
+
+		if (commit) {
+			wait_for_completion(&commit->cleanup_done);
+			drm_crtc_commit_put(commit);
+		}
+	}
+}
+
 void xe_display_pm_suspend(struct xe_device *xe, bool runtime)
 {
 	bool s2idle = suspend_to_idle();
···
 
 	if (!runtime)
 		intel_display_driver_suspend(xe);
+
+	xe_display_flush_cleanup_work(xe);
 
 	intel_dp_mst_suspend(xe);
 

drivers/gpu/drm/xe/xe_pm.c

···
 	for_each_gt(gt, xe, id)
 		xe_gt_suspend_prepare(gt);
 
+	xe_display_pm_suspend(xe, false);
+
 	/* FIXME: Super racey... */
 	err = xe_bo_evict_all(xe);
 	if (err)
 		goto err;
-
-	xe_display_pm_suspend(xe, false);
 
 	for_each_gt(gt, xe, id) {
 		err = xe_gt_suspend(gt);
···
 
 	xe_irq_resume(xe);
 
-	xe_display_pm_resume(xe, false);
-
 	for_each_gt(gt, xe, id)
 		xe_gt_resume(gt);
+
+	xe_display_pm_resume(xe, false);
 
 	err = xe_bo_restore_user(xe);
 	if (err)
···
 	mutex_unlock(&xe->mem_access.vram_userfault.lock);
 
 	if (xe->d3cold.allowed) {
+		xe_display_pm_suspend(xe, true);
+
 		err = xe_bo_evict_all(xe);
 		if (err)
 			goto out;
-		xe_display_pm_suspend(xe, true);
 	}
 
 	for_each_gt(gt, xe, id) {