Re: [PATCH] clocksource: arm_arch_timer: Don't assume clock runs in suspend

From: Stephen Boyd
Date: Tue Oct 18 2016 - 21:24:58 EST


On 10/04, Brian Norris wrote:
> Hi Marc,
>
> On Thu, Sep 29, 2016 at 05:08:47PM +0100, Marc Zyngier wrote:
> > On Tue, 27 Sep 2016 18:23:11 -0700
> > Brian Norris <briannorris@xxxxxxxxxxxx> wrote:
> > > On Tue, Sep 20, 2016 at 08:47:07AM +0100, Marc Zyngier wrote:
> > > <Begin side note>
> > > rk3288 (ARMv7 system widely used for our Chromebooks) has the same
> > > issue, except the kernel we're using for production (based on v3.14)
> > > doesn't have the following commit, which stopped utilizing the RTC:
> > >
> > > commit 0fa88cb4b82b5cf7429bc1cef9db006ca035754e
> > > Author: Xunlei Pang <pang.xunlei@xxxxxxxxxx>
> > > Date: Wed Apr 1 20:34:38 2015 -0700
> > >
> > > time, drivers/rtc: Don't bother with rtc_resume() for the nonstop clocksource
> > >
> > > And any mainline testing on rk3288 doesn't see the problem, because
> > > mainline doesn't support its lowest-power sleep modes well enough (see
> > > ROCKCHIP_ARM_OFF_LOGIC_DEEP in arch/arm/mach-rockchip/pm.c).
> >
> > Arghh... So even my favourite Chromebook (from which I'm typing this
> > email) is affected? Not very nice...
>
> Yep. But if you're running mainline, you just get to have high S3 power
> consumption instead!

Just curious, do we enter this state during cpuidle as well? Or
is it only across suspend that the clock stops working?

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