Dual-rate transceivers with ixgbe?

[Juli Mallett]

Hey all,

Has anyone out there been able to get link using a dual-rate
transceiver at 1gig with the ixgbe driver in FreeBSD?  I have an SFP+
NIC and an Intel-branded dual-rate transceiver but it will only get
link at 10gig.

I used the latest driver from FreeBSD trunk backported (which IIRC
didn't take any significant changes; jfv@ does a good job of keeping
the drivers working across branches) to 7.x for my testing.  A
similarly-versioned Linux driver (with only trivial and mostly
cosmetic differences in the hardware code outside of the main driver)
worked at 1gig just fine.  All testing was done with switches rather
than host-to-host connections.

It seems like someone else must have tried this and it seems like
there must just be some trivial difference in card initialization
between FreeBSD and Linux, so I thought I'd ask publicly to see if
anyone had patches.  I instrumented the code extensively but so far
have come up empty-handed.

Thanks,
Juli.