Re: [PATCH v3] xhci-pci: Set runtime PM as default policy on all xHC 1.2 or later devices

[Mathias Nyman]

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@xxxxxxxxxxxxxxx>
> > 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@xxxxxxx>
>
> Reviewed-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>

Thanks, added to queue

-Mathias