Ralf Baechle writes:
> > Have you verified that the newest code still works on the other MIPS
> > based systems? Also, is it possible to have (linux) binary compatability
> > between a mips Magnum or Millennium and an Indy?
>
> By principle there is no problem to feed these machines even with IRIX
> binaries. Right now the port to these machines assumes that it is running
> on the machine configured to little endian mode but porting to big endian
> should be easy.
Note, however, that running big-endian on the MIPS systems is a bit
of a hack. They were originally designed to be little-endian-only (a MIPS
management aberration), so running big-endian means that, in general,
I/O DMA has to be byte-swapped by software. RISCos would preferentially
write file systems on disks in native-endian format, which, if read on
a different system, would appear to be byte-swapped within each doubleword.
That is, RISCos would skip the byte-swapping on non-removable media, unless
the magic number in the superblock indicated that the disk was initialized
in true big-endian format. For all other media, RISCos would byte-swap,
but, since those were much lower data rate, the performance impact was
small.
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