utilizing David Jones' new MI NCR 5380 code. Ported from the sun3 ncr_si.c
and "sw" DMA code written by me.
This driver contains user-configurable "options", which can be set via the
"flags" directive in the kernel configuration file. By default, only
DMA is enabled. DMA completion interrupts and reselection may be enabled
by setting the appropriate bits with "flags". See si.c for details.
Note that DMA completion interrupts and reselection don't yet work on the
4/100 controller. I don't know why, and it's unlikely that I'll have
the opportunity to find out any time soon. DMA does work, and results
in a considerable performance increase.
DMA, DMA completion interrupts, and reslection all work on my 4/260 (VME)
system with modern SCSI-II disks.