Proposal to remove ARCNET support

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

Hey folks --

I am proposing that we remove support for ARCNET.  For those not familiar, ARCNET (Attached Resource Computer Network) is/was a 2.5Mb/s token passing network that had some popularity in the late-80s due to its lower cost and relative simplicity compared to the Ethernet of the same era, which still used a linear cabling scheme.  It was common with some Tandy and Commodore systems, and NetBSD supports the Standard Microsystems ARCNET chip that was widely used.

Ignatios Souvatzis wrote our ARCNET code, including the driver for the SMC90c26 / SMC90c56 ARCNET controller chip.

These days, ARCNET is largely obsolete.  It still has a niche use in industrial control, but it's long-gone from general purpose computing.  This code is not MP-safe, and while hardware is available (ARCNET hubs and some VME, ISA, and other controller board form-factors) from the Internet's auction house, it's relatively expensive for the performance you can get out of it and I see it as unlikely that any updates to this code would ever be tested.

I believe it's time to let it go.

Code in question:

net/if_arc.h
net/if_arcsubr.c

dev/ic/smc90cx6.c
dev/ic/smc90cx6reg.h
dev/ic/smc90cx6var.h

arch/amiga/dev/if_bah_zbus.c

Are there any objections?

-- thorpej