[patch 1/2] powerpc: rmb fix

[Paul Mackerras]

Nick Piggin writes:

> More than one device driver does raw/relaxed io accessors and expects the
> *mb functions to order them.

Can you point us at an example?

I don't think the semantics of the raw accessors are particularly well
defined (it's not even defined what endianness the data comes back in)
so I'd be surprised if there was any real definition of their
behaviour w.r.t. barriers.

Paul.