[PATCH 3/4] drm/amdgpu: Support snooped PTE flag

[Christian König]

Am 23.08.19 um 23:33 schrieb Kuehling, Felix:
> From: Oak Zeng <Oak.Zeng at amd.com>
>
> Set snooped PTE flag according to mapping flag. Write request to a
> page with snooped bit set, will send out invalidate probe request
> to TCC of the remote GPU where the vram page resides.
>
> Change-Id: I799f68ec7a5a1abf32075f5ef31051641a0b3736
> Signed-off-by: Oak Zeng <Oak.Zeng at amd.com>
> ---
>   drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c | 3 +++
>   1 file changed, 3 insertions(+)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c b/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
> index 9aafcda6c488..8a7c4ec69ae8 100644
> --- a/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
> +++ b/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
> @@ -604,6 +604,9 @@ static uint64_t gmc_v9_0_get_vm_pte_flags(struct amdgpu_device *adev,
>   	if (flags & AMDGPU_VM_PAGE_PRT)
>   		pte_flag |= AMDGPU_PTE_PRT;
>   
> +	if (flags & AMDGPU_VM_PAGE_INVALIDATE_PROBE)
> +		pte_flag |= AMDGPU_PTE_SNOOPED;
> +

That is still a NAK without further checks. We need to make absolutely 
sure that we don't set this when PCIe routing is in use.

Christian.

>   	return pte_flag;
>   }
>