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From: Doug Anderson <dianders@chromium.org>
Date: Tue, 31 Oct 2017 17:23:19 -0700
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Subject: Re: [RFC] Improving udelay/ndelay on platforms where that is possible
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Russell King - ARM Linux <linux@armlinux.org.uk>,
        Marc Gonzalez <marc_gonzalez@sigmadesigns.com>,
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Hi,

On Tue, Oct 31, 2017 at 10:45 AM, Linus Torvalds
<torvalds@linux-foundation.org> wrote:
> So I'm very much open to udelay improvements, and if somebody sends
> patches for particular platforms to do particularly well on that
> platform, I think we should merge them. But ...

If I'm reading this all correctly, this sounds like you'd be willing
to merge <https://patchwork.kernel.org/patch/9429841/>.  This makes
udelay() guaranteed not to underrun on arm32 platforms.

-Doug