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Date:   Tue, 29 Jan 2019 10:41:55 +0200
From:   Peter De Schrijver <pdeschrijver@nvidia.com>
To:     Thierry Reding <thierry.reding@gmail.com>
CC:     Joseph Lo <josephl@nvidia.com>,
        Daniel Lezcano <daniel.lezcano@linaro.org>,
        <linux-kernel@vger.kernel.org>,
        Jonathan Hunter <jonathanh@nvidia.com>,
        <linux-tegra@vger.kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        <linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH V2 2/6] clocksource: tegra: add Tegra210 timer driver
Message-ID: <20190129084155.GX7714@pdeschrijver-desktop.Nvidia.com>
References: <20190128091815.7040-1-josephl@nvidia.com>
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 <20190128150908.GB31317@ulmo>
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On Mon, Jan 28, 2019 at 04:09:08PM +0100, Thierry Reding wrote:

...

> 
> Up to here this is a duplicate of timer-tegra20.c. And a lot of
> tegra210_timer_init() is the same as tegra20_timer_init() as well. Can't
> we unify the two drivers instead?
> 
> The power cycle restrictions of the architected timer, do they not apply
> to chips earlier than Tegra210 either? So don't we need all of these
> additional features on the timer-tegra20.c driver as well? If so that

No. Chips prior to Tegra114 do not have an arch timer and the arch timer
does work correctly on Cortex-A15 so Tegra114 and Tegra124 can use it.
It's broken on Cortex-A57 though, so we can't use it as a wakeup source
on Tegra210.

Peter.