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    SubjectRe: [PATCH] fsldma: use PCI Read Multiple command

    On Apr 27, 2009, at 3:00 PM, David Hawkins wrote:

    >>> Can you give me an example of non-PCI memory that would be
    >>> non-prefetchable that you'd like us to try? We can see if our
    >>> host CPUs have an area like that ... we just need to know
    >>> what device to look for first :)
    >> You can mark the pci inbound window on the 83xx as non-prefetchable
    >> (assuming 83xx is host). On a x86 host I doubt there is any easy
    >> way to get non-prefetchable memory.
    > Yep, we were going to do that, but chose to use the
    > 1MB region already setup for the IMMRs since its already
    > marked as non-prefetchable. We were only doing reads, so
    > it wasn't going to hurt anything.
    > I doubt that marking one of the other BAR regions
    > as non-prefetchable will give a different result.
    > However, we're more than happy to double-check if
    > you'd like.

    Its possible you'll get a different result since IMMR is a register
    space internal and thats normally a completely different bus than
    memory would be (internal to the 83xx). I'd suggest double-checking w/
    a BAR marked non-prefetch pointing to real memory.

    - k

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      Last update: 2009-04-27 22:07    [W:0.021 / U:242.144 seconds]
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