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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Wed, 1 Nov 2017 12:09:19 -0700
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Subject: Re: [RFC] Improving udelay/ndelay on platforms where that is possible
To: Marc Gonzalez <marc_gonzalez@sigmadesigns.com>
Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk>,
        LKML <linux-kernel@vger.kernel.org>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
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On Wed, Nov 1, 2017 at 12:03 PM, Marc Gonzalez
<marc_gonzalez@sigmadesigns.com> wrote:
>
> By default, ndelay is implemented in terms of udelay.

That's very much *NOT* the case.

Yes, there is a *fallback* for when somebody doesn't do ndelay() at
all, but that doesn't make it the default.

It's just a "the architecture didn't implement ndelay at all, we'll
work around it".

So stop this idiocy already. About half of what I've seen in this
thread has been pure garbage.

                       Linus