> P.S. I wonder who cargo-culted BUS_DMA_STREAMING into these drivers.
>      Only the sparc64 does anything with that flag.  And to be honest
>     even I don't really know what that is about.

I think in the original architectures this requested a slightly different
style of bus transaction (which was typically longer, not just descriptors
being updated).  I think it was nothing more than a hint.

I wonder if it even mattered, back in those days, for the way OpenBSD actually
used the hardware.  It's probably a option in all the hardware, which only
matters in the really big iron case, which we never ran on..