Proposal to remove FDDI support

[Jason Thorpe <thorpej%me.com@localhost>]

Hey folks --

I am proposing that we remove support for FDDI.  For those not familiar, FDDI (Fiber Distributed Data Interface) is/was a 100Mb/s (or 200Mb/s, in some dual-attached-station configurations) token passing network that was able to run fairly long distances. Back in its heyday (mid-90s), it was a popular for use as a campus backbone.  As its name implies, it was originally a fiber interconnect, but was available over twisted-pair copper, as well (CDDI).

Matt Thomas wrote our FDDI code, along with a driver for the DEC "PDQ" FDDI controllers, which were found on PCI (DEFPA), EISA (DEFEA), and TURBOchannel (DEFTA) boards.

Alas, FDDI's time has passed.  It is no longer particularly useful (Ethernet being superior in speed these days), and the interfaces not particularly common.  As far as I know, we never supported any FDDI interfaces other than the DEC "PDQ" types (e.g. no Sun SBus FDDI interfaces).  This code is not MP-safe, and the lack of commonly-available hardware will make it practically impossible to test updates to the code.

I believe it's time to let it go.

Code in question:

net/if_fddi.h
net/if_fddisubr.c

dev/ic/pdq.c
dev/ic/pdqreg.h
dev/ic/pdqvar.h
dev/ic/pdq_ifsubr.c

dev/eisa/if_fea.c

dev/pci/if_fpa.c

dev/tc/if_fta.c

Are there any objections?

-- thorpej