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From: Arnd Bergmann <arnd@arndb.de>
To: Richard Kuo <rkuo@codeaurora.org>
Cc: linux-kernel@vger.kernel.org, linux-hexagon@vger.kernel.org
Subject: Re: [patch 08/36] Hexagon: Add delay functions
Date: Wed, 17 Aug 2011 21:38:35 +0200
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On Wednesday 17 August 2011 11:35:05 Richard Kuo wrote:
> +#include <asm/param.h>
> +
> +extern void __udelay(unsigned long usecs);
> +
> +#define udelay(usecs) __udelay((usecs))
> +
> +extern void __delay(unsigned long loops);

If you have any kind of reliable timer register, it's better
to poll that than to rely on a delay loop that is especially
inaccurate when running under a hypervisor.

That also speeds up boot time because you no longer need to
calibrate the delay loop.

	Arnd