[Nouveau] [PATCH v2] drm/nouveau/acpi: fix check for power resources support

[Peter Wu]

On Tue, Nov 01, 2016 at 09:24:23AM -0400, Alex Deucher wrote:
> On Tue, Nov 1, 2016 at 12:55 AM, Dave Airlie <airlied at gmail.com> wrote:
> > On 1 November 2016 at 08:48, Peter Wu <peter at lekensteyn.nl> wrote:
> >> Check whether the kernel really supports power resources for a device,
> >> otherwise the power might not be removed when the device is runtime
> >> suspended (DSM should still work in these cases where PR does not).
> >>
> >> This is a workaround for a problem where ACPICA and Windows 10 differ in
> >> behavior. ACPICA does not correctly enumerate power resources within a
> >> conditional block (due to delayed execution of such blocks) and as a
> >> result power_resources is set to false even if _PR3 exists.
> >>
> >> Fixes: 692a17dcc292 ("drm/nouveau/acpi: fix lockup with PCIe runtime PM")
> >> Link: https://bugs.freedesktop.org/show_bug.cgi?id=98398
> >> Reported-and-tested-by: Rick Kerkhof <rick.2889 at gmail.com>
> >> Reviewed-by: Mika Westerberg <mika.westerberg at linux.intel.com>
> >> Signed-off-by: Peter Wu <peter at lekensteyn.nl>
> >
> > I've appled it this and cc'ed stable to drm-fixes.
> >
> > Are we going to get ACPICA fixed?

The ACPI folks are aware of the problem, see this thread and its
follow-ups:
http://www.spinics.net/lists/linux-acpi/msg70050.html

> Looks like we may have hit this on radeon/amdgpu as well:
> https://bugs.freedesktop.org/show_bug.cgi?id=98505
> 
> Alex

That log seems to suggest that resume fails while this nouveau issue is
related to suspend not powering off a device. The root cause might be
different.
-- 
Kind regards,
Peter Wu
https://lekensteyn.nl