Messages in this thread | | | From | "Sosnowski, Maciej" <> | Date | Tue, 15 Sep 2009 17:06:52 +0100 | Subject | RE: [PATCH 05/18] ioat2+: add fence support |
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Williams, Dan J wrote: > In preparation for adding more operation types to the ioat3 path the > driver needs to honor the DMA_PREP_FENCE flag. For example the async_tx api > will hand xor->memcpy->xor chains to the driver with the 'fence' flag set on > the first xor and the memcpy operation. This flag in turn sets the 'fence' > flag in the descriptor control field telling the hardware that future > descriptors in the chain depend on the result of the current descriptor, so > wait for all writes to complete before starting the next operation. > > Note that ioat1 does not prefetch the descriptor chain, so does not > require/support fenced operations. > > Signed-off-by: Dan Williams <dan.j.williams@intel.com> > ---
Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
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