On Fri, 2021-05-07 at 08:07 -0500, Bjorn Helgaas wrote:
> [+cc Lukas]
>
> On Fri, May 07, 2021 at 12:32:20PM +0300, Konstantin Kharlamov wrote:
> > On Thu, 2021-05-06 at 16:48 -0500, Bjorn Helgaas wrote:
> > > [+cc Rafael, Andreas, linux-pm]
> > >
> > > On Thu, May 06, 2021 at 08:38:20PM +0300, Konstantin Kharlamov wrote:
> > > > On Macbook 2013 resuming from s2idle results in external monitor no
> > > > longer being detected, and dmesg having errors like:
> > > >
> > > > pcieport 0000:06:00.0: can't change power state from D3hot to D0
> > > > (config
> > > > space inaccessible)
> > > >
> > > > and a stacktrace. The reason turned out that the hw that the quirk
> > > > powers off does not get powered on back on resume.
> > >
> > > quirk_apple_poweroff_thunderbolt() was added in 2014 by 1df5172c5c25
> > > ("PCI: Suspend/resume quirks for Apple thunderbolt"). It claims
> > > "power is automatically restored before resume," so there must be
> > > something special about s2idle that prevents the power-on.
> > >
> > > IIUC this change will reduce the s2idle power savings. I would feel
> > > better about this if we understood what the difference was.
> > >
> > > > Thus, add a check for s2idle to the quirk, and do nothing if the suspend
> > > > mode is s2idle.
> > >
> > > Obviously the *hardware* hasn't changed since 1df5172c5c25. Is s2idle
> > > something that wasn't tested back then, or is this problem connected
> > > to an s2idle change since then? Can we identify a commit that
> > > introduced this problem? That would help with backporting or stable
> > > tags.
> > >
> > > > Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=212767
> > >
> > > Thanks for this! Would you mind attaching the output of
> > > "sudo lspci -vvv"? If you attach any other dmesg, could you
> > > use "dmesg --color=never" so the log doesn't include all the
> > > escape characters?
> >
> > Thank you! So, just to be clear: in lieu of Lukas Wunner's reply, do
> > you still want `lspci` and `dmesg` outputs, or are you okay with the
> > information Lukas provided?
>
> Yes, please attach at least lspci output. It helps understand the
> topology and may be useful in the future. I wish we had a similar
> bugzilla with more information about the original 1df5172c5c25.
Thanks! I attached the `sudo lspci -vvv` output to the bugreport, here's a direct link to the attachment https://bugzilla.kernel.org/attachment.cgi?id=296689
