[PATCH 2/2] drm/amdgpu: remove pointless ttm_eu usage from DM

[Harry Wentland]

On 2022-04-19 10:19, Christian König wrote:
> We just need to reserve the BO here, no need for using ttm_eu.
> 
> Signed-off-by: Christian König <christian.koenig at amd.com>

Acked-by: Harry Wentland <harry.wentland at amd.com>

Harry

> ---
>   .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 32 ++++++++++---------
>   1 file changed, 17 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> index 73423b805b54..91e9922b95b3 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/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,