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    SubjectRE: [PATCH] fsldma: use PCI Read Multiple command
    > > 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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      Last update: 2009-04-28 03:35    [W:0.019 / U:125.280 seconds]
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