Re: [PATCH] MIPS: Define __arch_swab64 for all mips r2 cpus (v2).

[Ralf Baechle <ralf@linux-mips.org>]

On Wed, Jul 01, 2009 at 02:36:31AM +0100, Maciej W. Rozycki wrote:

> > The problem with CPU_MIPS64_R2 in the kernel is that it means two unrelated
> > things:
> > 
> > 1) The cpu can execute all mips64r2 ISA instructions.
> > 
> > 2) The cpu requires that all worse case cache and execution hazards are
> > handled.
> > 
> > In the case of the Octeon processors, #1 is true, but we can get better
> > performance by omitting many of the hazard barriers because they are 
> > unneeded.
> 
>  Which is why I think a split of the semantics would be a good idea.

That's the idea since a long time.  There are far less uses of CONFIG_CPU_*
than there used to be historically - and usually they're a bug or at least
should be considered one.

  Ralf