[PATCH 4/4] drm/i915/gt: Revert ggtt_resume to previous logic

[Michael Cheng <michael.cheng@xxxxxxxxx>]

To avoid having to call wbinvd_on_all_cpus, revert i915_ggtt_resume and
i915_ggtt_resume_vm to previous logic [1].

[1]. 64b95df91f44 drm/i915: Assume exclusive access to objects inside resume

Suggested-by: Lucas De Marchi <lucas.demarchi@xxxxxxxxx>
Signed-off-by: Michael Cheng <michael.cheng@xxxxxxxxx>
---
 drivers/gpu/drm/i915/gt/intel_ggtt.c | 17 ++++++-----------
 drivers/gpu/drm/i915/gt/intel_gtt.h  |  2 +-
 2 files changed, 7 insertions(+), 12 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/intel_ggtt.c b/drivers/gpu/drm/i915/gt/intel_ggtt.c
index 04191fe2ee34..811bfd9d8d80 100644
--- a/drivers/gpu/drm/i915/gt/intel_ggtt.c
+++ b/drivers/gpu/drm/i915/gt/intel_ggtt.c
@@ -1305,10 +1305,9 @@ void i915_ggtt_disable_guc(struct i915_ggtt *ggtt)
  * Returns %true if restoring the mapping for any object that was in a write
  * domain before suspend.
  */
-bool i915_ggtt_resume_vm(struct i915_address_space *vm)
+void i915_ggtt_resume_vm(struct i915_address_space *vm)
 {
 	struct i915_vma *vma;
-	bool write_domain_objs = false;
 
 	drm_WARN_ON(&vm->i915->drm, !vm->is_ggtt && !vm->is_dpt);
 
@@ -1325,28 +1324,24 @@ bool i915_ggtt_resume_vm(struct i915_address_space *vm)
 		vma->ops->bind_vma(vm, NULL, vma->resource,
 				   obj ? obj->cache_level : 0,
 				   was_bound);
-		if (obj) { /* only used during resume => exclusive access */
-			write_domain_objs |= fetch_and_zero(&obj->write_domain);
-			obj->read_domains |= I915_GEM_DOMAIN_GTT;
+		if (obj) {
+			i915_gem_object_lock(obj, NULL);
+			WARN_ON(i915_gem_object_set_to_gtt_domain(obj, false));
+			i915_gem_object_unlock(obj);
 		}
 	}
 
-	return write_domain_objs;
 }
 
 void i915_ggtt_resume(struct i915_ggtt *ggtt)
 {
-	bool flush;
 
 	intel_gt_check_and_clear_faults(ggtt->vm.gt);
 
-	flush = i915_ggtt_resume_vm(&ggtt->vm);
+	i915_ggtt_resume_vm(&ggtt->vm);
 
 	ggtt->invalidate(ggtt);
 
-	if (flush)
-		wbinvd_on_all_cpus();
-
 	if (GRAPHICS_VER(ggtt->vm.i915) >= 8)
 		setup_private_pat(ggtt->vm.gt->uncore);
 
diff --git a/drivers/gpu/drm/i915/gt/intel_gtt.h b/drivers/gpu/drm/i915/gt/intel_gtt.h
index 4529b5e9f6e6..c86092054988 100644
--- a/drivers/gpu/drm/i915/gt/intel_gtt.h
+++ b/drivers/gpu/drm/i915/gt/intel_gtt.h
@@ -567,7 +567,7 @@ struct i915_ppgtt *i915_ppgtt_create(struct intel_gt *gt,
 				     unsigned long lmem_pt_obj_flags);
 
 void i915_ggtt_suspend_vm(struct i915_address_space *vm);
-bool i915_ggtt_resume_vm(struct i915_address_space *vm);
+void i915_ggtt_resume_vm(struct i915_address_space *vm);
 void i915_ggtt_suspend(struct i915_ggtt *gtt);
 void i915_ggtt_resume(struct i915_ggtt *ggtt);
 
-- 
2.25.1