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From:   Saravana Kannan <saravanak@google.com>
Date:   Mon, 27 Apr 2020 13:12:41 -0700
Message-ID: <CAGETcx9sc6oWSPK=aWJ+39i9eHAyg6iOf+Xf2oVECO+g1pFjtQ@mail.gmail.com>
Subject: Re: [PATCH 1/2] drivers/clocksource/timer-of: Remove __init markings
To:     Daniel Lezcano <daniel.lezcano@linaro.org>
Cc:     Baolin Wang <baolin.wang7@gmail.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Orson Zhai <orsonzhai@gmail.com>,
        Chunyan Zhang <zhang.lyra@gmail.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Android Kernel Team <kernel-team@android.com>
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On Mon, Apr 27, 2020 at 1:09 PM Daniel Lezcano
<daniel.lezcano@linaro.org> wrote:
>
> On 27/04/2020 21:04, Saravana Kannan wrote:
> > On Mon, Apr 27, 2020 at 10:13 AM Daniel Lezcano
> > <daniel.lezcano@linaro.org> wrote:
> >>
> >> On 13/04/2020 04:55, Baolin Wang wrote:
> >>> Hi Daniel,
> >>>
> >>> On Tue, Mar 24, 2020 at 1:59 PM Baolin Wang <baolin.wang7@gmail.com> wrote:
> >>>>
> >>>> From: Saravana Kannan <saravanak@google.com>
> >>>>
> >>>> This allows timer drivers to be compiled as modules.
> >>>>
> >>>> Signed-off-by: Saravana Kannan <saravanak@google.com>
> >>>> Signed-off-by: Baolin Wang <baolin.wang7@gmail.com>
> >>>
> >>> Do you have any comments for this patch set? Thanks.
> >>
> >> If my understanding is correct, this patch is part of the GKI picture
> >> where hardware drivers are converted to modules.
> >>
> >> But do we really want to convert timer drivers to modules ?
> >>
> >> Is the core time framework able to support that (eg. load + unload )
> >
> > So this will mainly be used for secondary timers that the system
> > supports. Not for the main one that's set up during early boot for
> > sched timer to work. For the primary timer during boot up, we still
> > expect that to be the default ARM timer and don't want/expect that to
> > be a module (it can't be).
>
> My question is about clockevents_config_and_register() for instance, is
> there a function to unregister in the core framework ?

We can just have these modules be "permanent" modules that can't be
unloaded. They just need to not implement module_exit().

-Saravana