Ok, so I've adjusted bus_dmamap_sync() to be R4000-friendly.  It _should_
DTRT (and R3000 people should see no functional difference).  If anyone
with an R4000 DECstation has a DEFTA, I'd like to know if it works!

Jason R. Thorpe                                       thorpej@nas.nasa.gov
NASA Ames Research Center                            Home: +1 408 866 1912
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