Izumi Tsutsui wrote;

>
>   [ ... NetBSD/arc ARCS chipset DMAing ... ]
>
> Anyway, I think it is easy to switch MI ncr53c9x driver.
> It's requires only glue functions and some DMA stuff
> like sys/dev/pci/pcscp.c.

It's rather nice to look at Digital's Scatter-Gather machinary design
found in NetBSD/alpha.  It was introduced in higher-end DEC3000 family,
and then inherited by multiple generations of Alpha system core chip
set design.  The design roots can be traced back to VAXie age and it's
worth looking at NetBSD/vax too.

Tohru Nishimura