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Date: Fri, 12 Jan 2007 14:37:23 +1100
From: Paul Mackerras <paulus@samba.org>
To: Sascha Hauer <s.hauer@pengutronix.de>
Subject: Re: [PATCH] add restart function for mpc52xx
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Sascha Hauer writes:

> > This suffers from the same bug mpc83xx_restart has.  We can NOT do an  
> > ioremap inside the restart function.  We may get called from  
> > interrupt context on a panic and will not be able to do the ioremap 
> > ().  The simplest thing is to do the mapping earlier in an init call  
> > and save the pointer, its not perfect, but better.
> > 
> 
> I'm beginning to hate this whole pseudo OF thing for embedded systems.

Not being able to ioremap at interrupt time has absolutely _nothing_
to do with the device tree.

> All we need to know is that we have a mpc52xx processor.

... until we get a system with a mpc52xx and some extra stuff.  Then
you say "OK, we just need a boardinfo_t" and then we get 57 different
variants of boardinfo_t and then we're back in the mess that arch/ppc
got into.

Paul.