From: Matt Porter <mporter@kernel•crashing.org>
To: Kumar Gala <galak@kernel•crashing.org>
Cc: linuxppc-embedded@ozlabs•org, "Jenkins, Clive" <Clive.Jenkins@xerox•com>
Subject: Re: Yosemite/440EP why are readl()/ioread32() setup to readlittle-endian?
Date: Wed, 1 Feb 2006 20:07:21 -0700 [thread overview]
Message-ID: <20060201200721.E16064@cox.net> (raw)
In-Reply-To: <Pine.LNX.4.44.0602011851490.22854-100000@gate.crashing.org>; from galak@kernel.crashing.org on Wed, Feb 01, 2006 at 06:54:09PM -0600
On Wed, Feb 01, 2006 at 06:54:09PM -0600, Kumar Gala wrote:
> On Wed, 1 Feb 2006, Peter Korsgaard wrote:
>
> > >>>>> "Matt" == Matt Porter <mporter@kernel•crashing.org> writes:
> >
> > Matt> read*/write* and ioread*/iowrite* generate outbound little
> > Matt> endian cycles on ALL arches, period. They are intended
> > Matt> only for PCI use and have generic names only because of
> > Matt> the assumption that "all the world is a PC".
> >
> > What is the preferred way of accessing non-PCI devices then? Direct
> > pointer access?
>
> No direct pointer access is bad. On PPC You can use
> in_be{8,16,32}/out_be{8,16,32}
Ack. Also, it should be pointed out that there are countless
examples of PPC drivers where this is done properly. 4xx, 83xx,
85xx, etc. on-chip peripherals all do this since they are
naturally BE registers.
-Matt
next prev parent reply other threads:[~2006-02-02 3:07 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-02-01 11:19 Yosemite/440EP why are readl()/ioread32() setup to readlittle-endian? Jenkins, Clive
2006-02-01 17:02 ` David Hawkins
2006-02-01 17:44 ` Matt Porter
2006-02-01 17:53 ` David Hawkins
2006-02-01 18:04 ` David Hawkins
2006-02-01 18:11 ` Eugene Surovegin
2006-02-01 18:20 ` David Hawkins
2006-02-01 18:23 ` Eugene Surovegin
2006-02-01 21:14 ` Peter Korsgaard
2006-02-02 0:54 ` Kumar Gala
2006-02-02 3:07 ` Matt Porter [this message]
2006-02-02 8:09 ` Peter Korsgaard
2006-02-02 9:08 ` Eugene Surovegin
2006-02-02 17:34 ` Dale Farnsworth
2006-02-02 14:21 ` Matt Porter
-- strict thread matches above, loose matches on Subject: below --
2006-02-01 18:35 Jenkins, Clive
2006-02-01 20:35 ` David Hawkins
2006-02-02 9:35 Jenkins, Clive
2006-02-02 9:46 ` Eugene Surovegin
2006-02-02 14:37 ` Matt Porter
2006-02-02 17:45 ` Eugene Surovegin
2006-02-02 18:16 ` Matt Porter
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