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Date: Wed, 13 Mar 2013 12:17:25 -0700
From: John Stultz <john.stultz@linaro.org>
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To: Feng Tang <feng.tang@intel.com>
CC: Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@elte.hu>,
        "H. Peter Anvin" <hpa@linux.intel.com>,
        Jason Gunthorpe <jgunthorpe@obsidianresearch.com>, x86@kernel.org,
        Len Brown <lenb@kernel.org>,
        "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>,
        linux-kernel@vger.kernel.org, gong.chen@linux.intel.com
Subject: Re: [PATCH v4 0/4] Add support for S3 non-stop TSC support.
References: <1363060608-22657-1-git-send-email-feng.tang@intel.com>
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On 03/11/2013 08:56 PM, Feng Tang wrote:
> Hi All,
>
> On some new Intel Atom processors (Penwell and Cloverview), there is
> a feature that the TSC won't stop in 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.h and timekeeping.c to support and utilizing
> it.
>
> The major change to timekeeping is the way to count suspended time,
> current way is trying to use the persistent clock first, and then
> try the rtc if persistent clock can't do it. This patch will change
> the trying order to:
> 	suspend-nonstop clocksource -> persistent clock -> rtc
>
> Please help to review them, thanks a lot!
>

Thanks!

I've gone ahead and queued these, with my minor modifications, for 3.10 
(pending further testing).

thanks
-john