> Full-duplex requires some support in the MAC, as well.  Many MACs determine
> it automatically based on electrical signals from the PHY... but some require
> frobbing of a control register directly, even when you put the PHY into
> full-duplex mode.
> 
The 'hme' and 'qec' fall into the category of needing to manually frob a
control register based on the status of duplex in the PHY.

The onboard phy on the 'qec+be' does not appear to support full duplex
operation.  I fiddled with it for awhile until I just gave up and decided
that it just wasn't going to happen.

But, 'qec+be's have a connector for hooking up external PHYs.  I think
that if an external phy were hooked up to the card, and the right bits
were twiddled on the MAC, then it would be possible to do full duplex
using this board.  (ie. BE_BR_TXCFG_FULLDPLX from bereg.h).  (I have no
proof one way or the other, though).

--Jason Wright
  jason@thought.net
  jason@openbsd.org