submitter, who *still* hasn't bothered to answer me back.
The thing which the submitter completely failed to mention is that
his 3c900B-TPO card has the transceiver selection in the EEPROM set
to "auto." You can tweak the setting using the 3C90XCFG.EXE utility
that 3Com provides with the card. I'm not sure if it's supposed to
default to auto or if the user fiddled with it. Currently, the xl
driver only does autoselection for 10/100 NICs (i.e. those with NWAY
autonegotiation capabilities). For the 10baseT, 10base5, 10base2,
10baseFL and 100baseFX cards, the driver sets the default media to
whatever the EEPROM transceiver selector says. The problem is that
the "auto" selection is mistakenly identified as "10/100 NWAY
autoselection mode" and this is not handled correctly: the default
media ends up being chosen as 100baseTX, which doesn't work because
we've only added 10baseT media types to the ifmedia word. This leads
to a panic in ifmedia_set() (something else which the submitter never
bothered to mention).
A workaround for this is to re-run the 3C90XCFG.EXE utility and change
the transceiver selection to something besides "auto." I have also
patched the driver to watch for the "auto" setting in the non-miibus
case and select a reasonable default based on the card type instead of
falling through to 100baseTX and exploding.
PR: misc/13665