From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Tue, 27 Mar 2007 18:05:11 -0700
From: Geoff Levand <geoffrey.levand@am.sony.com>
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To: "Mark A. Greer" <mgreer@mvista.com>
Subject: Re: [PATCH] powerpc: Disable external interrupts in bootwrapper
References: <20070327222840.GA1266@mag.az.mvista.com>
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Cc: linuxppc-dev <Linuxppc-dev@ozlabs.org>, Paul Mackerras <paulus@samba.org>
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Mark A. Greer wrote:
> Disable external interrupts very early in the bootwrapper in case
> the firmware left a device generating interrupts.

This is just a guess at what is happening, but I think the OF on my
G5 uses the timer interrupt as a kind of watchdog timer, so that if
the loaded code hangs, OF will regain control.  If you disable
interrupts, you may loose this functionality.

-Geoff