drm/amdgpu: implement TLB flush fence

The problem is that when (for example) 4k pages are replaced
with a single 2M page we need to wait for change to be flushed
out by invalidating the TLB before the PT can be freed.

Solve this by moving the TLB flush into a DMA-fence object which
can be used to delay the freeing of the PT BOs until it is signaled.

V2: (Shashank)
    - rebase
    - set dma_fence_error only in case of error
    - add tlb_flush fence only when PT/PD BO is locked (Felix)
    - use vm->pasid when f is NULL (Mukul)

V4: - add a wait for (f->dependency) in tlb_fence_work (Christian)
    - move the misplaced fence_create call to the end (Philip)

V5: - free the f->dependency properly

V6: (Shashank)
    - light code movement, moved all the clean-up in previous patch
    - introduce params.needs_flush and its usage in this patch
    - rebase without TLB HW sequence patch

V7:
   - Keep the vm->last_update_fence and tlb_cb code until
     we can fix the HW sequencing (Christian)
   - Move all the tlb_fence related code in a separate function so that
     its easier to read and review

V9: Addressed review comments from Christian
    - start PT update only when we have callback memory allocated

V10:
    - handle device unlock in OOM case (Christian, Mukul)
    - added Christian's R-B

Cc: Christian Koenig <[email protected]>
Cc: Felix Kuehling <[email protected]>
Cc: Rajneesh Bhardwaj <[email protected]>
Cc: Alex Deucher <[email protected]>
Acked-by: Felix Kuehling <[email protected]>
Acked-by: Rajneesh Bhardwaj <[email protected]>
Tested-by: Rajneesh Bhardwaj <[email protected]>
Reviewed-by: Shashank Sharma <[email protected]>
Reviewed-by: Christian Koenig <[email protected]>
Signed-off-by: Christian Koenig <[email protected]>
Signed-off-by: Shashank Sharma <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>

1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c
index 124389a6bf48..601df0ce8290 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c
@@ -972,7 +972,7 @@ int amdgpu_vm_ptes_update(struct amdgpu_vm_update_params *params,
 			while (cursor.pfn < frag_start) {
 				/* Make sure previous mapping is freed */
 				if (cursor.entry->bo) {
-					params->table_freed = true;
+					params->needs_flush = true;
 					amdgpu_vm_pt_free_dfs(adev, params->vm,
 							      &cursor,
 							      params->unlocked);