On Wed, 29 Jul 1998, Gregory McGarry wrote:

> I don't really like the sprinkling of defines throughout the i386
> tree to specify level triggered interrupts (eg npx on isa).  Is this
> the best approach, or should these drivers be reproduced in
> /sys/arch/i386/mca/?  Same can be said for dev/isa/com.c, dev/isa/lpt.c
> etc)?
> 
> This is why I ask.  Updating it to bus_space isn't a problem, doing
> it the Right Way could be.

Things should be going in dev/mca for the most part, and arch/i386/mca for
the rest. RS/6000 workstations used MCA also, and MCA support is the one
thing really holding them back from NetBSD. 

Basically, all the calls to isa_intr_establish should be calls to
mca_intr_establish instead.

Are ALL interrupts level triggered on mca systems? Did any mca systems
ever also have an isa bus? If not, then just copy most of the files over
to i386/mca, make them level triggered, and then just don't have the isa
bus attach if the mca bus is found.

Most of the drivers, like lpt, com, wdc, aic, bha, ... now are bus indep.,
and have _isa specific attachments. So 1.3 (or certainly -current) should
need fewer patches (just populate the .../mca/ directories).

Take care,

Bill