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

[Bao, Ping A]

Hi Stefan,

I added this device ID for Alder Lake (SoC) to the previous patch for Ubuntu-kernel hirsute 5.11.22. Without adding this device ID, the system cannot enter PC10 state once VMD is enabled in BIOS .

After applying this patch (new device ID), this system can enter PC10 state (low power) successfully.

Thanks,
Ping

> -----Original Message-----
> From: Stefan Bader <stefan.bader at canonical.com>
> Sent: Friday, July 23, 2021 12:35 AM
> To: Ping Bao <pingbao at gmail.com>; kernel-team at lists.ubuntu.com
> Cc: Bao, Ping A <ping.a.bao at intel.com>; You-Sheng Yang
> <vicamo.yang at canonical.com>
> Subject: NACK/Cmnt: [PATCH] UBUNTU: SAUCE: PCI/ASPM: Add AlderLake
> ASPM support for links under VMD domain
> 
> On 22.07.21 20:10, Ping Bao wrote:
> > BugLink: https://bugs.launchpad.net/bugs/1889384
> >
> > Add AlderLake ASPM support for links under VMD to reach deeper power
> > saving state.
> >
> > Signed-off-by: Ping Bao <ping.a.bao at intel.com>
> > ---
> 
> The bug report which is referred to suggest that this is already fixed. Also the
> submission gives not indication to which kernel this should be applied if it were
> still required.
> 
> -Stefan
> 
> >   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) },
> >   	{ }
> >   };
> >
> >
>