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From:   Alex Deucher <alexdeucher@gmail.com>
Date:   Thu, 23 Jul 2020 14:01:17 -0400
Message-ID: <CADnq5_Nqziz6TKfk7U6QvBjZtV7ibBfwwym1kTb1Q4t-cz04JQ@mail.gmail.com>
Subject: Re: [PATCH] PCI/P2PDMA: Add AMD Zen 2 root complex to the list of
 allowed bridges
To:     Logan Gunthorpe <logang@deltatee.com>
Cc:     LKML <linux-kernel@vger.kernel.org>,
        Linux PCI <linux-pci@vger.kernel.org>,
        Bjorn Helgaas <bhelgaas@google.com>,
        =?UTF-8?Q?Christian_K=C3=B6nig?= <christian.koenig@amd.com>,
        Huang Rui <ray.huang@amd.com>
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On Thu, Jul 23, 2020 at 1:43 PM Logan Gunthorpe <logang@deltatee.com> 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@deltatee.com>
> Cc: Bjorn Helgaas <bhelgaas@google.com>
> Cc: Christian K=C3=B6nig <christian.koenig@amd.com>
> Cc: Huang Rui <ray.huang@amd.com>
> Cc: Alex Deucher <alexdeucher@gmail.com>

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

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

> ---
>  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
>