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Subject: Re: [PATCH 1/2] powerpc: Add a proper syscall for switching endianness
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Tony Breeds <tony@bakeyournoodle.com>
Date: Mon, 16 Mar 2015 11:07:53 +1100
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Cc: Scott Wood <scottwood@freescale.com>, Jeremy Kerr <jk@ozlabs.org>,
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On Mon, 2015-03-16 at 09:59 +1100, Tony Breeds wrote:
> On Fri, Mar 13, 2015 at 05:38:46PM +1100, Michael Ellerman wrote:
> 
> > According to Paul there are no working implementations of LE on 32-bit cpus, so
> > the syscall doesn't really make sense there.
> 
> Ummm that doesn't sound right.  I don't think there is an LE linux userspace
> but I'm pretty sure we had 32-bit working on 44x.  Check where Ian did the
> initial LE patchset.

Yes but that's done by using a per-page endian flag, not a global MSR
bit, so we never supported a syscall to switch there and never will.

Cheers,
Ben.