Re: [PATCH] PCI/P2PDMA: Add AMD Zen 2 root complex to the list of allowed bridges

[Alex Deucher]

On Thu, Jul 23, 2020 at 1:43 PM Logan Gunthorpe <logang@xxxxxxxxxxxx> wrote:
>
> The AMD Zen 2 root complex (Starship/Matisse) was tested for P2PDMA
> transactions between root ports and found to work. Therefore add it
> to the list.
>
> Signed-off-by: Logan Gunthorpe <logang@xxxxxxxxxxxx>
> Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> Cc: Christian KÃnig <christian.koenig@xxxxxxx>
> Cc: Huang Rui <ray.huang@xxxxxxx>
> Cc: Alex Deucher <alexdeucher@xxxxxxxxx>

Starting with Zen, all AMD platforms support P2P for reads and writes.

Reviewed-by: Alex Deucher <alexander.deucher@xxxxxxx>

> ---
>  drivers/pci/p2pdma.c | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c
> index e8e444eeb1cd..3d67a1ee083e 100644
> --- a/drivers/pci/p2pdma.c
> +++ b/drivers/pci/p2pdma.c
> @@ -284,6 +284,8 @@ static const struct pci_p2pdma_whitelist_entry {
>         {PCI_VENDOR_ID_AMD,     0x1450, 0},
>         {PCI_VENDOR_ID_AMD,     0x15d0, 0},
>         {PCI_VENDOR_ID_AMD,     0x1630, 0},
> +       /* AMD ZEN 2 */
> +       {PCI_VENDOR_ID_AMD,     0x1480, 0},
>
>         /* Intel Xeon E5/Core i7 */
>         {PCI_VENDOR_ID_INTEL,   0x3c00, REQ_SAME_HOST_BRIDGE},
>
> base-commit: ba47d845d715a010f7b51f6f89bae32845e6acb7
> --
> 2.20.1
>