Date: Fri, 19 Nov 2004 16:24:59 +0900
From: Yasushi SHOJI <yashi@atmark-techno.com>
To: Jeff Garzik <jgarzik@pobox.com>
Cc: Linux Kernel list <linux-kernel@vger.kernel.org>
Subject: Re: readl/writel: swap or not to swap
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Hi Jeff,

At Thu, 18 Nov 2004 23:09:19 -0500,
Jeff Garzik wrote:
> 
> > is there any rule we should follow?  Is the ppc way the right
> > direction to follow? I can ifdef anytime for my own use but I just
> > want to know what _should_ be done.
> 
> 
> readl()/writel() are defined as being for the PCI bus (little endian). 
> As such, they should swap on big endian platforms.

thanks for your input.  so read*() and write*() family should _only_
be used for pci bus?

the "Understanding the linux kernel" state that those macro should be
used for i/o shared memory.  and it has three bus listed: isa, vlb,
pci.

I'm a bit confused... i know some arch have bus-dedicated read and
write macro, ie isa_readl().  is this the way to go?

sorry for dumb questions.  if this is RTFM thing, just tell me.

thanks,
--
            yashi

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