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Date: Mon, 21 Jan 2013 14:55:02 +0100
From: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
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To: Feng Tang <feng.tang@intel.com>
CC: Thomas Gleixner <tglx@linutronix.de>, John Stultz <john.stultz@linaro.org>,
        Ingo Molnar <mingo@elte.hu>, "H. Peter Anvin" <hpa@linux.intel.com>,
        x86@kernel.org, Len Brown <lenb@kernel.org>,
        linux-kernel@vger.kernel.org
Subject: Re: [RFC PATCH 0/5] Add support for S3 non-stop TSC support.
References: <1358750325-21217-1-git-send-email-feng.tang@intel.com>
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On 1/21/2013 7:38 AM, Feng Tang wrote:
> Hi All,
>
> On some new Intel Atom processors (Penwell and Cloverview), there is
> a feature that the TSC won't stop S3, say the TSC value won't be
> reset to 0 after resume. This feature makes TSC a more reliable
> clocksource and could benefit the timekeeping code during system
> suspend/resume cycles.
>
> The enabling efforts include adding new flags for this feature,
> modifying clocksource.c and timekeeping.c to support and utilizing
> it.
>
> One remaining question is inside the timekeeping_resume(), we don't
> know if it is called by resuming from suspend(s2ram) or from
> hibernate(s2disk), as there is no easy way to check it currently.
> But it doesn't hurt as these Penwell/Cloverview platforms only have
> S3 state, and no S4.
>
> Please help to review them, thanks!

The patches look reasonable to me.

Thanks,
Rafael

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