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    Subject[PATCH 0 of 3] 32-bit MMIO copy routine
    Following some discussion with Roland, and patterned after the style
    anointed by Linus last week, here is a new version of the 32-bit MMIO
    copy routine needed by our InfiniPath device.

    The name of the routine has changed from memcpy_toio32 to
    __raw_memcpy_toio32. This reflects the basic nature of the routine;
    it dodes not guarantee the order in which writes are performed, nor does
    it perform a memory barrier after it is done.

    The reason for this is that our chip treats the first and last writes
    to some MMIO regions specially; our driver performs those directly using
    writel, and uses __raw_memcpy_toio32 for the bits in between.

    Regarding the specialised x86_64 implementation, Andi Kleen asked me
    to perform some measurements of its performance impact. It makes a
    difference of about 5% in performance on moderately large copies over
    the HyperTransport bus, compared to the generic implementation.

     \ /
      Last update: 2006-01-06 21:31    [W:0.017 / U:1.728 seconds]
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