My Realport Tulip card recenly died, so I acquired a Netgear GA-511
gigabit cardbus NIC, hoping against hope that it would be a bcm5704m,
not a RealTek; assuming that in the worst case, if_re would work.

of course, Netgear used the realtek chip. But re(4) supports only PCI
attachments, not cardbus.  Any objections to splitting sys/dev/pci/if_re.c
into two (chipset, and pci-attachment), so I can try kluding up a
cardbus attachment?  (has anyone tried that already?)