Sungem with iMac Rev-B

David A. Gatwood dgatwood at
Mon Apr 29 14:59:49 EST 2002

On Sun, 28 Apr 2002, Aurel Wisse wrote:

> I am trying to modify the bmac to force the PHY to
> abandon autonegotiation and to use 10Mb/s and half
> duplex. "Reverse engineering" the bmac code leads
> nowhere. The bmac_init_phy doesn't give a lot of info,
> except a couple of undocumented constants written via
> bmac_mif_write, and the mif_write writes to the MIFCSR
> register which is undocumented in the bmac.h file.
> This is terribly frustrating as Apple is obviously
> able to do it with their Duplex tool hack. Hence, it
> *can* be done. Why can't they just send us their
> sourcecode for the Duplex tool? Does anybody have a
> direct line to Apple?

Looked at the Darwin sources lately?  BMacEnet::miiInitializePHY appears
to describe the "normal" setup in a way that should make it pretty obvious
how to set it up in non-normal ways -- or perhaps not -- I've never dealt
with the chip, personally -- but it's a good starting point, anyway.


David A. Gatwood                                dgatwood at
Developer Docs Writer                             dgatwood at
Apple Computer                                  dgatwood at

                    Check out my weekly web comic:

** Sent via the linuxppc-dev mail list. See

More information about the Linuxppc-dev mailing list