drm/amdgpu: remove pointless ttm_eu usage from DM

We just need to reserve one BO here, no need for using ttm_eu to reserve
multiple BOs.
Signed-off-by: Christian König <christian.koenig@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220419141915.122157-2-christian.koenig@amd.com

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c

@@ -7583,9 +7583,6 @@ static int dm_plane_helper_prepare_fb(struct drm_plane *plane,
 	struct amdgpu_device *adev;
 	struct amdgpu_bo *rbo;
 	struct dm_plane_state *dm_plane_state_new, *dm_plane_state_old;
-	struct list_head list;
-	struct ttm_validate_buffer tv;
-	struct ww_acquire_ctx ticket;
 	uint32_t domain;
 	int r;
 
@@ -7598,18 +7595,19 @@ static int dm_plane_helper_prepare_fb(struct drm_plane *plane,
 	obj = new_state->fb->obj[0];
 	rbo = gem_to_amdgpu_bo(obj);
 	adev = amdgpu_ttm_adev(rbo->tbo.bdev);
-	INIT_LIST_HEAD(&list);
 
-	tv.bo = &rbo->tbo;
-	tv.num_shared = 1;
-	list_add(&tv.head, &list);
-
-	r = ttm_eu_reserve_buffers(&ticket, &list, false, NULL);
+	r = amdgpu_bo_reserve(rbo, true);
 	if (r) {
 		dev_err(adev->dev, "fail to reserve bo (%d)\n", r);
 		return r;
 	}
 
+	r = dma_resv_reserve_fences(rbo->tbo.base.resv, 1);
+	if (r) {
+		dev_err(adev->dev, "reserving fence slot failed (%d)\n", r);
+		goto error_unlock;
+	}
+
 	if (plane->type != DRM_PLANE_TYPE_CURSOR)
 		domain = amdgpu_display_supported_domains(adev, rbo->flags);
 	else
@@ -7619,19 +7617,16 @@ static int dm_plane_helper_prepare_fb(struct drm_plane *plane,
 	if (unlikely(r != 0)) {
 		if (r != -ERESTARTSYS)
 			DRM_ERROR("Failed to pin framebuffer with error %d\n", r);
-		ttm_eu_backoff_reservation(&ticket, &list);
-		return r;
+		goto error_unlock;
 	}
 
 	r = amdgpu_ttm_alloc_gart(&rbo->tbo);
 	if (unlikely(r != 0)) {
-		amdgpu_bo_unpin(rbo);
-		ttm_eu_backoff_reservation(&ticket, &list);
 		DRM_ERROR("%p bind failed\n", rbo);
-		return r;
+		goto error_unpin;
 	}
 
-	ttm_eu_backoff_reservation(&ticket, &list);
+	amdgpu_bo_unreserve(rbo);
 
 	afb->address = amdgpu_bo_gpu_offset(rbo);
 
@@ -7663,6 +7658,13 @@ static int dm_plane_helper_prepare_fb(struct drm_plane *plane,
 	}
 
 	return 0;
+
+error_unpin:
+	amdgpu_bo_unpin(rbo);
+
+error_unlock:
+	amdgpu_bo_unreserve(rbo);
+	return r;
 }
 
 static void dm_plane_helper_cleanup_fb(struct drm_plane *plane,