Re: [PATCH] [POWERPC] Improve (in|out)_beXX() asm code

[Scott Wood]

Alan Cox wrote:
> > It looks like we rely on -fno-strict-aliasing to prevent reordering 
> > ordinary memory accesses (such as to DMA descriptors) past the I/O 
>
> DMA descriptors in main memory are dependant on cache behaviour anyway
> and the dma_* operators should be the ones enforcing the needed behaviour.

What about memory obtained from dma_alloc_coherent()?  We still need a 
sync and a compiler barrier.  The current I/O accessors have the former, 
but not the latter.

-Scott
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