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Date: Wed, 26 Sep 2007 15:41:56 -0500
From: Scott Wood <scottwood@freescale.com>
To: Rune Torgersen <runet@innovsys.com>
Subject: Re: [PATCH4/4] [POWERPC] Fix cpm_uart driver
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On Wed, Sep 26, 2007 at 03:32:29PM -0500, Rune Torgersen wrote:
> > From: Scott Wood
> > Maybe that's how it was, but the current code initializes it (more or
> > less) directly with IMAP_ADDR, which also gets fed into ioremap.
> > 
> > One of the two has got to be wrong.
> 
> arch/ppc maps the immr area 1:1 into kernel memory, so ioremap and
> physical are the same.
> See arch/ppc/syslib/m8260_setup.c, line 208 (function m8260_map_io)

We were talking about 8xx, not 82xx -- is it always identity mapped there?

If so, then why bother with the ioremap in immr_map_size() in
arch/ppc/8xx_io/commproc.c?  And why compare the result from ioremap() with
a raw identity-mapped address?

-Scott