Re: powerpc: introduce asm/swab.h

[Benjamin Herrenschmidt <benh@kernel.crashing.org>]

> Ok, I committed it as a quick-fix. I'm not sure that is necessarily the 
> final one, but at least it is better than not compiling.
> 
> For example, it's kind of silly to use two __fswab32()'s with other 
> oddness if that one just falls back on __constant_swab32: maybe we'd want 
> to make sure that we'd use ___constant_swab64() in that case, and only do 
> the whole __SWAB_64_THRU_32__ if we really have a __arch_swab32() 
> function.
> 
> Of course, I do hope that anybody who #defines __SWAB_64_THRU_32__ already 
> has that __arch_swab32() thing, so it's likely fine.
> 
> I also wonder whether gcc generates better code with a union than with 
> that 64-bit math...

Allright, it boots here on a powerbook, though IDE seems to be
busticated (it gets lost interrupts trying to enable DMA, though it does
fallback properly to PIO), but I think that's unrelated. I'll have a
closer look tomorrow.

Cheers,
Ben.