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Date:   Thu, 20 Apr 2023 13:51:05 +0300
From:   Mika Westerberg <mika.westerberg@linux.intel.com>
To:     Kai-Heng Feng <kai.heng.feng@canonical.com>
Cc:     bhelgaas@google.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
Subject: Re: [PATCH v2 4/4] PCI/DPC: Disable DPC interrupt during suspend
Message-ID: <20230420105105.GO66750@black.fi.intel.com>
References: <20230420015830.309845-1-kai.heng.feng@canonical.com>
 <20230420015830.309845-4-kai.heng.feng@canonical.com>
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On Thu, Apr 20, 2023 at 09:58:30AM +0800, Kai-Heng Feng wrote:
> PCIe service that shares IRQ with PME may cause spurious wakeup on
> system suspend.
> 
> Since AER is conditionally disabled in previous patch, also apply the
> same logic to disable DPC which depends on AER to work.
> 
> PCIe Base Spec 5.0, section 5.2 "Link State Power Management" states
> that TLP and DLLP transmission is disabled for a Link in L2/L3 Ready
> (D3hot), L2 (D3cold with aux power) and L3 (D3cold), so we don't lose
> much here to disable DPC during system suspend.
> 
> This is very similar to previous attempts to suspend AER and DPC [1],
> but with a different reason.
> 
> [1] https://lore.kernel.org/linux-pci/20220408153159.106741-1-kai.heng.feng@canonical.com/
> Link: https://bugzilla.kernel.org/show_bug.cgi?id=216295
> 
> Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>

Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>