Date: Mon, 2 Jun 2008 10:11:02 +0200
From: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
To: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: benh@kernel.crashing.org, Matthew Wilcox <matthew@wil.cx>,
       Linus Torvalds <torvalds@linux-foundation.org>,
       David Miller <davem@davemloft.net>, linux-arch@vger.kernel.org,
       scottwood@freescale.com, linuxppc-dev@ozlabs.org,
       alan@lxorguk.ukuu.org.uk, linux-kernel@vger.kernel.org,
       tpiepho@freescale.com
Subject: Re: MMIO and gcc re-ordering issue
Message-ID: <20080602101102.0d8979c5@hskinnemo-gx745.norway.atmel.com>
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Geert Uytterhoeven <geert@linux-m68k.org> wrote:
> On Fri, 30 May 2008, Haavard Skinnemoen wrote:
> > Maybe we need another interface that does not do byteswapping but
> > provides stronger ordering guarantees?
> 
> The byte swapping depends on the device/bus.

Of course. But isn't it reasonable to assume that a device integrated
on the same silicon as the CPU is connected to a somewhat sane bus
which doesn't require any byte swapping?

> So what happened to the old idea of putting the accessor function pointers
> in the device/bus structure?

Don't know. I think it sounds like overkill to replace a simple load or
store with an indirect function call.

Haavard
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