On Wed, Sep 16, 2020 at 11:04 AM Alyssa Rosenzweig
<alyssa.rosenzw...@collabora.com> wrote:
> > So I get a performance regression with the dma-coherent approach, even if 
> > it's
> > clearly the cleaner.
> That's bizarre -- this should really be the faster of the two.

Coherency may not be free. CortexA9 had something like 4x slower
memcpy if SMP was enabled as an example. I don't know if there's
anything going on like that specifically here. If there's never any
CPU accesses mixed in with kmscube, then there would be no benefit to

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