>Well, my first goal (once I start spending time on this again), is to get
>the n32 ABI working.  To  do this we'll need a reference implementation,
>i.e. the SGI.  For porting NetBSD itself, a serial console is necessary,

Ah, okay. I would have simply tried to get NetBSD (at least the
kernel) to compile with the SGI IRIX toolchain as a first step.