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Message-ID: <7c08c4c8-562d-553f-e513-c925080300a7@linux.intel.com>
Date:   Tue, 11 Oct 2022 16:16:25 +0300
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Subject: Re: [PATCH v3] xhci-pci: Set runtime PM as default policy on all xHC
 1.2 or later devices
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To:     Mika Westerberg <mika.westerberg@linux.intel.com>,
        Mario Limonciello <mario.limonciello@amd.com>
Cc:     Mathias Nyman <mathias.nyman@intel.com>,
        Mehta Sanju <Sanju.Mehta@amd.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20221010160022.647-1-mario.limonciello@amd.com>
 <Y0T68lC6bUY7dg7D@black.fi.intel.com>
From:   Mathias Nyman <mathias.nyman@linux.intel.com>
In-Reply-To: <Y0T68lC6bUY7dg7D@black.fi.intel.com>
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On 11.10.2022 8.11, Mika Westerberg wrote:
> On Mon, Oct 10, 2022 at 11:00:21AM -0500, Mario Limonciello wrote:
>> For optimal power consumption of USB4 routers the XHCI PCIe endpoint
>> used for tunneling must be in D3.  Historically this is accomplished
>> by a long list of PCIe IDs that correspond to these endpoints because
>> the xhci_hcd driver will not default to allowing runtime PM for all
>> devices.
>>
>> As both AMD and Intel have released new products with new XHCI controllers
>> this list continues to grow. In reviewing the XHCI specification v1.2 on
>> page 607 there is already a requirement that the PCI power management
>> states D3hot and D3cold must be supported.
>>
>> In the quirk list, use this to indicate that runtime PM should be allowed
>> on XHCI controllers. The following controllers are known to be xHC 1.2 and
>> dropped explicitly:
>> * AMD Yellow Carp
>> * Intel Alder Lake
>> * Intel Meteor Lake
>> * Intel Raptor Lake
>>
>> Suggested-by: Mathias Nyman <mathias.nyman@linux.intel.com>
>> Link: https://www.intel.com/content/dam/www/public/us/en/documents/technical-specifications/extensible-host-controler-interface-usb-xhci.pdf
>> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
> 
> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

Thanks, added to queue

-Mathias