In <200003170356.MAA02972@mirage.ceres.dti.ne.jp>
I wrote:

> In <Pine.NEB.4.10.10003161704460.9666-100000@pain.brini.com>
> mark@causality.com wrote:

> > > I'm trying to use NCR 53c875 PCI SCSI on my CATS,
> > > but it does not work.
> > Hi,
> >   Yep I have seen this problem. A long while back I remember some comments
> > from Jason saying that there were issues with the driver and that it
> > needed a good rewrite. Since then I have not tried it.

> I guess Jason said ncr.c did not support I/O mapped (kern/6565).
> But it seems that ncr on CATS uses memory mapped.
> 
> I also pick up NCR_IOMAPPED code from NetBSD/pc98 sources and
> try the kernel with "options NCR_IOMAPPED", it still does not work.
> 
> I will look more about this issue.

I notice that ncr.c has *no* bus_dmamap_sync(9).
There are many data accessed via DMA, but most of them do not
use bus_dma(9). It assumes that KVA is 32bit and there is
hardware support for DMA cache coherency.

ncr.c in OpenBSD has some (bogus) support for mips CPU,
but I agree current ncr.c should completely be re-written...
---
Izumi Tsutsui
tsutsui@ceres.dti.ne.jp