[vortex] 3C905TX doesn't see 10Mbps hub till unplugged/replugged

[Donald Becker]

On Mon, 26 Jun 2000, Bogdan Costescu wrote:

> > We can't make generalized statements about 3Com.
> > You must understand how 3Com does their chips.  They design the core, with
> > MII-like connections and send it out to a fab house.  The fab house
> > adds a MII transceiver that they have a license for, and creates a mask that
> > is licensed for specific fab lines.  3Com tries to keep at least three fab
> > houses ready to produce chips, and orders from whichever is least expensive
> > at the time.  That means that the "same" chip might have several different
> > transceivers.
> 
> Very entertaining!!! But coming back to our problem, 3Com should have  a
> method of accesing the right registers. Is it something like:
> 
> 	if (ASIC_ver == 1234)
> 	else if (ASIC_ver == 5678)... ?

This might break the very next chip revision.  If we keep to standard MII
behavior, rather than rely on additional features, we have a better chance
of continuing to work.


Donald Becker				becker@scyld.com
Scyld Computing Corporation		http://www.scyld.com
410 Severn Ave. Suite 210		Annapolis MD 21403