Re: [PATCH v1 0/2] PCI/ASPM: Fix LTR issues

From: Rafael J. Wysocki
Date: Fri Feb 22 2019 - 04:39:07 EST


On Friday, February 22, 2019 5:58:24 AM CET Bjorn Helgaas wrote:
> On Mon, Feb 11, 2019 at 04:55:33PM -0600, Bjorn Helgaas wrote:
> > These are to fix a couple LTR-related issues found while investigating
> > https://bugzilla.kernel.org/show_bug.cgi?id=201469
> >
> > I don't claim that these fix the whole problem of that bugzilla, but I
> > think it's pretty clear that these are problems we need to fix, so I want
> > to give these a little more exposure.
> >
> > Feedback welcome!
> >
> > ---
> >
> > Bjorn Helgaas (2):
> > PCI/ASPM: Use LTR if already enabled by platform
> > PCI/ASPM: Save LTR Capability for suspend/resume
> >
> >
> > drivers/pci/pci.c | 53 +++++++++++++++++++++++++++++++++++++++++++++++++--
> > drivers/pci/probe.c | 36 ++++++++++++++++++++++-------------
> > 2 files changed, 74 insertions(+), 15 deletions(-)
>
> I applied these to pci/aspm for v5.1.
>
> I think Vidya is absolutely right that we also need to save/restore
> the ASPM L1 Substates capability. But I haven't had a chance to
> write that up yet, and I think these two patches by themselves
> are an improvement even without ASPM L1 SS.

Agreed.

Cheers,
Rafael