Subject: Re: IMPORTANT: MACHINE_ARCH WRONG ON MIPS PLATFORMS
To: Warner Losh <imp@village.org>
From: Jason Thorpe <thorpej@nas.nasa.gov>
List: port-mips
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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