Subject: Re: IMPORTANT: MACHINE_ARCH WRONG ON MIPS PLATFORMS
To: Warner Losh <imp@village.org>
From: Jason Thorpe <thorpej@nas.nasa.gov>
List: tech-toolchain
Date: 07/23/1998 11:04:38
On Thu, 23 Jul 1998 11:57:12 -0600 
 Warner Losh <imp@village.org> wrote:

 > In message <199807231750.TAA17410@kurt.tools.de> Wolfgang Solfrank writes:
 > : Correct me if I'm wrong, but isn't the endianess on mips a hardware feature,
 > : i.e. wired by motherboard logic?
 > 
 > You are wrong :-).  At least the R4000 (and I think the R3000) have a
 > bit that says "run in the opposite mode" which allows one to run
 > userland big endian binaries on a little endian machine.  This feature
 > was put in place for DEC, iirc, because they had to run some big
 > endian binaries on their ulrix boxes (little endian) for something or
 > another.

The R4000 can select this on a per-ASID basis, I believe.  On the R3000,
it's "all or nothing".

Jason R. Thorpe                                       thorpej@nas.nasa.gov
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