From:   Thomas Gleixner <tglx@linutronix.de>
To:     John Stultz <john.stultz@linaro.org>,
        Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc:     Joel Daniels <jdaniels@sent.com>, Stephen Boyd <sboyd@kernel.org>,
        linux-kernel@vger.kernel.org,
        Alessandro Zummo <a.zummo@towertech.it>,
        linux-rtc@vger.kernel.org, x86@kernel.org
Subject: Re: Time keeping while suspended in the presence of persistent
 clock drift
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Date:   Wed, 15 Dec 2021 23:33:10 +0100
Message-ID: <87pmpxlcrd.ffs@tglx>
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On Wed, Dec 15 2021 at 14:02, John Stultz wrote:
> On Wed, Dec 15, 2021 at 1:32 PM Alexandre Belloni
>> I'd rather lean towards the timekeeping code doing that. The RTC
>
> Heh, touche'!  :)
>
>> subsystem doesn't know which RTC has to be used.
>
> Though the RTC layer *is* the one that tracks which RTC is used, via
> the logic in drivers/rtc/class.c, and the timekeeping core already has
> adjtimex for timekeeping corrections, so if we're correcting
> underlying RTCs it seems such tuning would best be done in the RTC
> layer.
>
> Though how the persistent_clock interface ties into such corrections
> would be a separate thing.

Might be the final trigger to get rid of that leftover from the last
millenium?

Thanks,

        tglx