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Re: what is the purpose of the following LE->BE patch to arch/mips/inclu

To: Manuel Lauss <manuel.lauss@gmail.com>
Subject: Re: what is the purpose of the following LE->BE patch to arch/mips/include/asm/io.h?
From: "Robert P. J. Day" <rpjday@crashcourse.ca>
Date: Sat, 21 Feb 2015 03:27:15 -0500 (EST)
Cc: Matt Turner <mattst88@gmail.com>, "linux-mips@linux-mips.org" <linux-mips@linux-mips.org>
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On Sat, 21 Feb 2015, Manuel Lauss wrote:

> On Sat, Feb 21, 2015 at 9:11 AM, Robert P. J. Day <rpjday@crashcourse.ca> 
> wrote:
> >
> >   has anyone else ever needed to do this? or is this some weird,
> > one-off hack that perhaps applies *only* to some bizarre feature of
> > this board?
>
> My guess is that the peripherals attached to the internal bus
> only undestand little endian, and the bus doesn't do byte swaps when
> the core isn't configured for LE. I.e. the BE feature is only
> implemented in the mips core and the rest was designed for LE only.

  ok, that makes sense ... so it's very likely a "issue with *this*
particular board and setup" kind of thing. thanks.

rday

-- 

========================================================================
Robert P. J. Day                                 Ottawa, Ontario, CANADA
                        http://crashcourse.ca

Twitter:                                       http://twitter.com/rpjday
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