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Date:   Wed, 21 Jan 2015 14:49:27 +0100
From:   Ralf Baechle <ralf@linux-mips.org>
To:     Markos Chandras <Markos.Chandras@imgtec.com>
Cc:     Joshua Kinard <kumba@gentoo.org>,
        David Daney <ddaney.cavm@gmail.com>,
        Linux MIPS List <linux-mips@linux-mips.org>
Subject: Re: [PATCH] MIPS: Display CPU byteorder in /proc/cpuinfo
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On Wed, Jan 21, 2015 at 10:22:30AM +0000, Markos Chandras wrote:

> >>> What would use this?  Or in other words, why is this needed?
> >>
> >> It was a patch I started including years ago in Gentoo's mips-sources, and just
> >> never thought much about.  I know it was submitted several times in the past,
> >> but I can't recall what, if any objection was ever made.  No harm in sending it
> >> in again...
> > 
> > Clarification, submitted several times in the past by others.  I think I sent
> > it in once prior, but never got review or feedback.
> > 
> I believe this patch is mostly useful for cores that can boot in both LE
> and BE so being able to tell the byteorder from cpuinfo can be helpful
> at times. Having readelf and other tools in your userland may not always
> be the case, but you surely have "cat" :)
> 
> So that patch looks good to me but i think the #ifdefs can be avoided.
> Can we use
> 
> if (config_enabled(CONFIG_CPU_BIG_ENDIAN) {
> } else {
> }
> 
> stuff instead?

Exactly the code Joshua is submitting is what has been there until commit
874124ebb630 (Merge with Linux 2.4.15.) in 2001.  One reason to remove it
was that I had a prototype of a kernel supporting the execution of
application of native and the other byte order working and the field in
/proc/cpuinfo was plain lying in that case.  Not a terribly relevant
reason in retrospective but I'm wondering if just in case we should
rename the field to kernel_byteorder?

  Ralf