Re: A simple question about readw, readw and the like

From: Abramo Bagnara (abramo@alsa-project.org)
Date: Thu Jul 27 2000 - 06:47:37 EST

"David S. Miller" wrote:
>
> From: Francois Wautier <fw@fwconsult.com>
> Date: Thu, 27 Jul 2000 14:57:48 +0700
>
> So what are the advantages/problems associated with using readw,
> writel and the like? Is this a way to get compatibility across
> various platforms?
>
> Derefencing the return pointer from ioremap() and not using the readw
> etc. interfaces is almost guarenteed to not work on any platform
> other than x86. On Sparc64 for example the return from ioremap()
> happens to be a physical address and will OOPS on you on any direct
> derefence of that pointer, readw() and friends do the access in the
> correct manner.

Does this means that there is no way to mmap the PCI IO space on any
platform other than ia32? 

-- 
Abramo Bagnara                       mailto:abramo@alsa-project.org

Opera Unica
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It sounds good!

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