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Re: Little-endian PCI bus master



ray@corp.cirrus.com wrote


>One of the immediate applications I have is : I want to hook this
little-endian
>only PCI master silicon to a PowerPC 603e. And as far as I understand it,
the
>PMC 603e is a bi-endian processor.  Does that means I can set the PMC603e
to
>little-endian mode and worry nothing else ?!


I would suspect the choice of endian modes would better be left to the
operating system...  I doubt the rest of the system would be real happy if
you suddenly change the global host endian state (disk drivers, graphics,
etc... ouch!).

personally, I'd look into dealing with it in the software.  Surely there is
at least one buffer copy or some such where the data gets moved and
processed by the CPU, doesn't the PPC architecture have a byteswap opcode?

Now, if this is a powermac apple system, I believe those have a swap
aperture built into their bridge, but I don't know if that works for a
busmaster

-jrp