On Jul 14,  1:11pm, Mark Brinicombe wrote:
> On Tue, 14 Jul 1998, Markus Baeurle wrote:
> 
...
> > -If no DMA is done (which is the only working mode for now), this is done in
> > cscattach() (with csc and sc being pointers to a ncr53c9x_softc):
> >  if(csc->sc_dc == NULL)
> >    sc->sc_flags |= NCR_NODMA;
> > Now there is no such define any more in 1.26. What's the equivalent?
> > Is it ncr53c9x_dmaselect?
> 
> You may like to have a look at some of the Amiga drivers e.g.
> amiga/dev/flsc.c
> A quick glance at the code indicates that it has support for PIO mode as
> well as DMA. From memory the NODMA stuff was an extra flag Scott Stevens
> added to support non-dma modes but this can be implemented within the DMA
> frame work of the driver.
> 
> The immediate thought is would be to perhaps base a new csc driver on
> something like the flsc driver with the DMA code removed and just always
> force the PIO support to be active.

  I have a non-DMA version of an Amiga driver that was a test for a
"generic" PIO driver for all the supported Phase 5 SCSI interfaces.  I
think it was a bit unstable though - I seem to recall it getting into some
kind of trouble when I tried to exercise the disk(s).  I didn't pursue the
reason for that since the DMA versions were more important.

Michael