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References: <20230512000014.118942-1-kai.heng.feng@canonical.com> <20230512000014.118942-2-kai.heng.feng@canonical.com>
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From:   Kai-Heng Feng <kai.heng.feng@canonical.com>
Date:   Fri, 14 Jul 2023 16:14:32 +0800
Message-ID: <CAAd53p6KEMJzraFn5GWGfEWQQ6WJmKGxtuGRuP2esAib+6s+Lw@mail.gmail.com>
Subject: Re: [PATCH v6 2/3] PCI/AER: Disable AER interrupt on suspend
To:     bhelgaas@google.com
Cc:     mika.westerberg@linux.intel.com, koba.ko@canonical.com,
        sathyanarayanan.kuppuswamy@linux.intel.com,
        Mahesh J Salgaonkar <mahesh@linux.ibm.com>,
        "Oliver O'Halloran" <oohall@gmail.com>,
        linuxppc-dev@lists.ozlabs.org, linux-pci@vger.kernel.org,
        linux-kernel@vger.kernel.org
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On Fri, May 12, 2023 at 8:01=E2=80=AFAM Kai-Heng Feng
<kai.heng.feng@canonical.com> wrote:
>
> PCIe services that share an IRQ with PME, such as AER or DPC, may cause a
> spurious wakeup on system suspend. To prevent this, disable the AER inter=
rupt
> notification during the system suspend process.
>
> As Per PCIe Base Spec 5.0, section 5.2, titled "Link State Power Manageme=
nt",
> TLP and DLLP transmission are disabled for a Link in L2/L3 Ready (D3hot),=
 L2
> (D3cold with aux power) and L3 (D3cold) states. So disabling the AER
> notification during suspend and re-enabling them during the resume proces=
s
> should not affect the basic functionality.
>
> Link: https://bugzilla.kernel.org/show_bug.cgi?id=3D216295
> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
> Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>

A gentle ping...

> ---
> v6:
> v5:
>  - Wording.
>
> v4:
> v3:
>  - No change.
>
> v2:
>  - Only disable AER IRQ.
>  - No more check on PME IRQ#.
>  - Use helper.
>
>  drivers/pci/pcie/aer.c | 22 ++++++++++++++++++++++
>  1 file changed, 22 insertions(+)
>
> diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c
> index 1420e1f27105..9c07fdbeb52d 100644
> --- a/drivers/pci/pcie/aer.c
> +++ b/drivers/pci/pcie/aer.c
> @@ -1356,6 +1356,26 @@ static int aer_probe(struct pcie_device *dev)
>         return 0;
>  }
>
> +static int aer_suspend(struct pcie_device *dev)
> +{
> +       struct aer_rpc *rpc =3D get_service_data(dev);
> +       struct pci_dev *pdev =3D rpc->rpd;
> +
> +       aer_disable_irq(pdev);
> +
> +       return 0;
> +}
> +
> +static int aer_resume(struct pcie_device *dev)
> +{
> +       struct aer_rpc *rpc =3D get_service_data(dev);
> +       struct pci_dev *pdev =3D rpc->rpd;
> +
> +       aer_enable_irq(pdev);
> +
> +       return 0;
> +}
> +
>  /**
>   * aer_root_reset - reset Root Port hierarchy, RCEC, or RCiEP
>   * @dev: pointer to Root Port, RCEC, or RCiEP
> @@ -1420,6 +1440,8 @@ static struct pcie_port_service_driver aerdriver =
=3D {
>         .service        =3D PCIE_PORT_SERVICE_AER,
>
>         .probe          =3D aer_probe,
> +       .suspend        =3D aer_suspend,
> +       .resume         =3D aer_resume,
>         .remove         =3D aer_remove,
>  };
>
> --
> 2.34.1
>