[PATCH] UBUNTU: SAUCE: PCI/ASPM: Add AlderLake ASPM support for links under VMD domain

[Kai-Heng Feng]

On Thu, Jul 29, 2021 at 7:11 AM Bao, Ping A <ping.a.bao at intel.com> wrote:
>
> Hi Kai-Heng,
>
> > -----Original Message-----
> > From: Kai-Heng Feng <kai.heng.feng at canonical.com>
> > Sent: Tuesday, July 27, 2021 7:44 PM
> > To: pingbao at gmail.com
> > Cc: Kernel team list <kernel-team at lists.ubuntu.com>; Bao, Ping A
> > <ping.a.bao at intel.com>; Wong, Anthony <anthony.wong at canonical.com>;
> > David E. Box <david.e.box at linux.intel.com>
> > Subject: Re: [PATCH] UBUNTU: SAUCE: PCI/ASPM: Add AlderLake ASPM support
> > for links under VMD domain
> >
> > [+Cc Anthony, David]
> >
> > Hi Ping,
> >
> > On Fri, Jul 23, 2021 at 1:41 PM Ping Bao <pingbao at gmail.com> wrote:
> > >
> > > BugLink: https://bugs.launchpad.net/bugs/1889384
> > >
> > > Add AlderLake ASPM support for links under VMD to reach deeper power
> > > saving state.
> >
> > I was told by David that ADL VMD ASPM should be enabled by BIOS. So wonder
> > why the patch is necessary?
>
> Just talked with David. This feature has not been implemented yet.

Okay, please follow [1] to do the SRU, thanks!

[1] https://wiki.ubuntu.com/Kernel/Dev/StablePatchFormat

Kai-Heng

>
> Ping
>
> >
> > Kai-Heng
> >
> > >
> > > Signed-off-by: Ping Bao <ping.a.bao at intel.com>
> > > ---
> > >  drivers/pci/quirks.c | 3 ++-
> > >  1 file changed, 2 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index
> > > fb13b3109a43..baa727330cdc 100644
> > > --- a/drivers/pci/quirks.c
> > > +++ b/drivers/pci/quirks.c
> > > @@ -5650,7 +5650,7 @@ DECLARE_PCI_FIXUP_CLASS_HEADER(0x1ac1,
> > 0x089a,
> > >                                PCI_CLASS_NOT_DEFINED, 8,
> > > apex_pci_fixup_class);
> > >
> > >  /*
> > > - * Device [8086:9a09], [8086:a0b0] and [8086:a0bc]
> > > + * Device [8086:9a09], [8086:a0b0], [8086:a0bc] and [8086:464d]
> > >   * BIOS may not be able to access config space of devices under VMD domain,
> > so
> > >   * it relies on software to enable ASPM for links under VMD.
> > >   */
> > > @@ -5658,6 +5658,7 @@ static const struct pci_device_id vmd_bridge_tbl[] =
> > {
> > >         { PCI_VDEVICE(INTEL, 0x9a09) },
> > >         { PCI_VDEVICE(INTEL, 0xa0b0) },
> > >         { PCI_VDEVICE(INTEL, 0xa0bc) },
> > > +       { PCI_VDEVICE(INTEL, 0x464d) },
> > >         { }
> > >  };
> > >
> > > --
> > > 2.25.1
> > >
> > >
> > > --
> > > kernel-team mailing list
> > > kernel-team at lists.ubuntu.com
> > > https://lists.ubuntu.com/mailman/listinfo/kernel-team