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From: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
To: Geert Uytterhoeven <geert@linux-m68k.org>
Subject: Re: MMIO and gcc re-ordering issue
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Cc: linux-arch@vger.kernel.org, Matthew Wilcox <matthew@wil.cx>,
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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