[PATCH 1/1] drm/amdgpu: Flush TLB after mapping for VG20+XGMI

[Tomasz Moń]

On 4/1/22 21:57, Philip Yang wrote:
> For VG20 + XGMI bridge, all mappings PTEs cache in TC, this may have
> stall invalid PTEs in TC because one cache line has 8 pages. Need always
> flush_tlb after updating mapping.
> 
> Signed-off-by: Philip Yang <Philip.Yang at amd.com>
> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 6 ++++++
>   1 file changed, 6 insertions(+)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> index f0aec04111a3..687c9a140645 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> @@ -837,6 +837,12 @@ int amdgpu_vm_update_range(struct amdgpu_device *adev, struct amdgpu_vm *vm,
>   		goto error_unlock;
>   	}
>   
> +	/* Vega20+XGMI where PTEs get inadvertently cached in L2 texture cache,
> +	 * heavy-weight flush TLB unconditionally.
> +	 */
> +	flush_tlb |= (adev->gmc.xgmi.num_physical_nodes &&
> +		      adev->ip_versions[GC_HWIP][0] == IP_VERSION(9, 4, 0));
> +
>   	memset(&params, 0, sizeof(params));
>   	params.adev = adev;
>   	params.vm = vm;

On top of what commit does this work?

It does not apply at top of v5.18-rc1.

It does apply, but fails to compile, on top of "drm/amdkfd: Create file 
descriptor after client is added to smi_clients list" that is commit:
   * cbe879c87245ce6272afe6456dbc8ce2c8f38d64 in amd-staging-drm-next
   * e45422695c196dbc665a95526c85ff4b8752aff2 in drm-next
fetched from https://gitlab.freedesktop.org/agd5f/linux.git

The compile error is due to flush_tlb being undeclared.

Best Regards,
Tomasz Mon