[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <7969e8c1-8fb2-4f47-9770-c6d1be48bb69@linaro.org>
Date: Fri, 31 May 2019 16:33:29 +0200
From: Daniel Lezcano <daniel.lezcano@...aro.org>
To: Marek Szyprowski <m.szyprowski@...sung.com>,
linux-kernel@...r.kernel.org, linux-samsung-soc@...r.kernel.org,
linux-arm-kernel@...ts.infradead.org
Cc: Thomas Gleixner <tglx@...utronix.de>,
Krzysztof Kozlowski <krzk@...nel.org>,
Chanwoo Choi <cw00.choi@...sung.com>,
Bartlomiej Zolnierkiewicz <b.zolnierkie@...sung.com>
Subject: Re: [PATCH v3] clocksource: exynos_mct: Increase priority over ARM
arch timer
On 30/05/2019 12:50, Marek Szyprowski wrote:
> Exynos SoCs based on CA7/CA15 have 2 timer interfaces: custom Exynos MCT
> (Multi Core Timer) and standard ARM Architected Timers.
>
> There are use cases, where both timer interfaces are used simultanously.
> One of such examples is using Exynos MCT for the main system timer and
> ARM Architected Timers for the KVM and virtualized guests (KVM requires
> arch timers).
>
> Exynos Multi-Core Timer driver (exynos_mct) must be however started
> before ARM Architected Timers (arch_timer), because they both share some
> common hardware blocks (global system counter) and turning on MCT is
> needed to get ARM Architected Timer working properly.
>
> To ensure selecting Exynos MCT as the main system timer, increase MCT
> timer rating. To ensure proper starting order of both timers during
> suspend/resume cycle, increase MCT hotplug priority over ARM Archictected
> Timers.
>
> Signed-off-by: Marek Szyprowski <m.szyprowski@...sung.com>
> Reviewed-by: Krzysztof Kozlowski <krzk@...nel.org>
> Reviewed-by: Chanwoo Choi <cw00.choi@...sung.com>
Applied, thanks
--
<http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs
Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook |
<http://twitter.com/#!/linaroorg> Twitter |
<http://www.linaro.org/linaro-blog/> Blog
Powered by blists - more mailing lists