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SubjectRE: [PATCH] fsldma: use PCI Read Multiple command
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> > You are assuming the PCI memory space is prefetchable( no 
> > side effect) for DMA.
> > Is it possible that DMA is from non-prefetchable memory space?
>
> This should be a safe assumption for this driver. Remember, this
> driver just does offload memcpy, from one region to another. So the
> PCI memory that you are reading from should be just a buffer of data,
> and there should be side-effect of reading it.
>
> However, I would like to see a comment at the top of the file warning
> people that copying from PCI memory will result in prefetched reads.

How about FIFO RAM case?


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