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From:   Linus Walleij <linus.walleij@linaro.org>
Date:   Tue, 20 Nov 2018 10:53:10 +0100
Message-ID: <CACRpkdZCFFAmArh20Sn7Z-FTYfreWw9cXfVN6iJNR1wAQD7gpg@mail.gmail.com>
Subject: Re: [RFC PATCH v2 07/14] m68k: atari: Convert to clocksource API
To:     fthain@telegraphics.com.au
Cc:     Geert Uytterhoeven <geert@linux-m68k.org>, schwab@linux-m68k.org,
        Arnd Bergmann <arnd@arndb.de>, schivers@csc.com.au,
        Thomas Gleixner <tglx@linutronix.de>,
        Daniel Lezcano <daniel.lezcano@linaro.org>,
        schmitzmic@gmail.com, John Stultz <john.stultz@linaro.org>,
        linux-m68k@lists.linux-m68k.org,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
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On Tue, Nov 20, 2018 at 10:30 AM Finn Thain <fthain@telegraphics.com.au> wrote:
> On Tue, 20 Nov 2018, Linus Walleij wrote:

> > As with the Amiga, this chip also has an RTC clock that should go to the
> > RTC subsystem, naturally.
>
> I think some Atari's have an MC146818, which is drivers/rtc/rtc-cmos.c,
> arch/alpha/kernel/rtc.c etc.

Indeed, some systems have more than one RTC, often one in their
SoC silicon and one battery backed elsewhere (like a dedicated
chip on I2C or inside a PMIC).

We usually just register more of them. The RTC subsystem can
handle any amount. It's up to userspace to figure out which RTC
to actually use, which is not so good, we should probably
have some heuristic like a quality indicator on them.

Yours,
Linus Walleij