Ok, so a DHV-11 can be treated as a DHU-11, but it still has problems.

I've filed a bug on it (#8991) to remind me to get back to it (or to nudge
Ragge :-)

For what its worth slot ordering doesn't change the behavior, nor does the
presence or absense of the W1,W2 jumpers (I'm in a Q/CD back plane). If the
kernel attaches the DHV-11 at 160500, and there is an MSCP controller at
160340, then you get sporadic segvs. [The CSR selection BTW came from the
configure option on the boot prom and is necessary in order for VMS to see
everything correctly]

So I've lost 8 serial ports, but I've also got an M3119 aka CXY08 which
looks a bit like a DHV-11 except that it has different chips :-). It is an
8 port Async mux with S-box handles. Does anyone know what driver might
talk to it?

--Chuck