Re: [PATCH v2] clocksource: arm_global_timer: fix suspend resume

From	John Stultz <john.stultz@linaro.org>
Newsgroups	linux.kernel
Subject	Re: [PATCH v2] clocksource: arm_global_timer: fix suspend resume
Date	2015-11-20 20:20 +0100
Message-ID	<qwZnY-2Zc-11@gated-at.bofh.it> (permalink)
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On Fri, Nov 20, 2015 at 10:46 AM, Marc Zyngier <marc.zyngier@arm.com> wrote:
>
> This patch has a very specific purpose: instructing the core code that
> this timer will never stop ticking, ever. It is really targeted at
> virtual machines, whose timer is backed by the host timer, even when the
> VM is not running.
>
> Using it on actual hardware is may not be the best idea, specially in
> the presence of PM.

And actually, the CLOCK_SOURCE_SUSPEND_NONSTOP flag was added to
support real hardware, so its not just limited to VMs. But that
hardware does have to keep the lights on for the counter backing the
clocksource, and I'm not sure how common it ever became.

thanks
-john
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Thread

[PATCH v2] clocksource: arm_global_timer: fix suspend resume Grygorii Strashko <grygorii.strashko@ti.com> - 2015-11-20 15:00 +0100
  Re: [PATCH v2] clocksource: arm_global_timer: fix suspend resume santosh shilimkar <santosh.shilimkar@oracle.com> - 2015-11-20 18:30 +0100
    Re: [PATCH v2] clocksource: arm_global_timer: fix suspend resume Grygorii Strashko <grygorii.strashko@ti.com> - 2015-11-20 19:40 +0100
      Re: [PATCH v2] clocksource: arm_global_timer: fix suspend resume Marc Zyngier <marc.zyngier@arm.com> - 2015-11-20 19:50 +0100
        Re: [PATCH v2] clocksource: arm_global_timer: fix suspend resume santosh shilimkar <santosh.shilimkar@oracle.com> - 2015-11-20 20:00 +0100
          Re: [PATCH v2] clocksource: arm_global_timer: fix suspend resume Grygorii Strashko <grygorii.strashko@ti.com> - 2015-11-20 20:20 +0100
        Re: [PATCH v2] clocksource: arm_global_timer: fix suspend resume John Stultz <john.stultz@linaro.org> - 2015-11-20 20:20 +0100
      Re: [PATCH v2] clocksource: arm_global_timer: fix suspend resume John Stultz <john.stultz@linaro.org> - 2015-11-20 20:10 +0100
        Re: [PATCH v2] clocksource: arm_global_timer: fix suspend resume Grygorii Strashko <grygorii.strashko@ti.com> - 2015-11-20 20:30 +0100
          Re: [PATCH v2] clocksource: arm_global_timer: fix suspend resume John Stultz <john.stultz@linaro.org> - 2015-11-20 20:40 +0100
            Re: [PATCH v2] clocksource: arm_global_timer: fix suspend resume Grygorii Strashko <grygorii.strashko@ti.com> - 2015-11-20 21:50 +0100
        Re: [PATCH v2] clocksource: arm_global_timer: fix suspend resume Thomas Gleixner <tglx@linutronix.de> - 2015-11-20 20:30 +0100

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