Re: [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.koe...@amd.com>

Acked-by: Harry Wentland <harry.wentl...@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,