I finally go video display to work on RiscServer 2200...
I had to add a patch to arc/machdep.c to reset
the vga registors, load a default font,etc. in
order for 'vga raster display' driver from
Bang Jun-Young to work.

Prebuilt bootable kernels can be download
from http://204.57.142.148/NEC/RISCServer.html .
Video,scsi,cdrom and ethernet now work!
Next project ... attempt to get 'cirrus'
xserver to work.