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Subject: Re: [PATCH 1/2] clocksource/drivers/exynos_mct: Prioritise Arm arch
 timer on arm64
To:     Will Deacon <will@kernel.org>
Cc:     Chanwoo Choi <cw00.choi@samsung.com>, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org,
        Marek Szyprowski <m.szyprowski@samsung.com>,
        Krzysztof Kozlowski <krzk@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>,
        Thomas Gleixner <tglx@linutronix.de>
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From:   Daniel Lezcano <daniel.lezcano@linaro.org>
Message-ID: <3ba202d9-a679-834a-685f-12c6f9eb9c38@linaro.org>
Date:   Mon, 21 Jun 2021 12:18:38 +0200
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On 21/06/2021 12:10, Will Deacon wrote:

[ ... ]

>>> exynos4_mct_frc_start() is called unconditionally from probe via
>>> exynos4_clocksource_init() so as long as the mct probes first, then the
>>> arch timer should work, no? The rating shouldn't affect that.
>>
>> How do you ensure the exynos mct is probed before the arch timer ?
>>
>> The Makefile provides the right order, but the dependency is implicit.
> 
> Currently, I think it's done by the order of the CPU hotplug notifiers (
> see the hunk of 6282edb72bed which touches cpuhotplug.h).

Ah, right. Indeed whatever the DT order, the cpuhotplug order solves the
dependency.

Chanwoo, are fine with this change ?


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