From: Arnd Bergmann <arnd@arndb.de>
To: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Ralf Baechle <ralf@linux-mips.org>, linux-mips@linux-mips.org,
        linux-kernel@vger.kernel.org, Richard Henderson <rth@twiddle.net>,
        Geert Uytterhoeven <geert@linux-m68k.org>,
        "Rafael J. Wysocki" <rjw@rjwysocki.net>
Subject: Re: no-op delay loops
Date: Mon, 30 Nov 2015 22:44:56 +0100
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On Monday 30 November 2015 22:29:26 Rasmus Villemoes wrote:
> 
> OK, thanks. That's a very very long time ago.
> 
> FWIW, the remaining instances that my trivial coccinelle script found
> are
> 
> ./arch/alpha/boot/main.c:187:1-4: no-op delay loop
> ./arch/m68k/68000/m68VZ328.c:86:10-13: no-op delay loop
> ./arch/m68k/bvme6000/config.c:338:2-5: no-op delay loop
> ./arch/m68k/coldfire/m53xx.c:533:1-4: no-op delay loop
> ./drivers/cpufreq/cris-artpec3-cpufreq.c:85:3-6: no-op delay loop
> ./drivers/cpufreq/cris-etraxfs-cpufreq.c:85:3-6: no-op delay loop
> ./drivers/tty/hvc/hvc_opal.c:313:3-6: no-op delay loop
> ./drivers/tty/hvc/hvc_vio.c:289:3-6: no-op delay loop
> 
> (cc += a few people). The tty ones use volatile, so they probably work,
> though one might still want to use the *delay API.
> 
> 

I suspect the tty users do it like this to get console output
before calibrate_delay_loop() is called.

	Ard
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