On Mon, Aug 17, 1998 at 03:11:29PM -0700, Matt Thomas wrote:
> 1) It may seem trivial but it would be nice instead of backplane0,
>    mainbus0 was used (like most other ports).  Mostly for consistency
>    but also because I don't consider the latter VAXen to have 
>    backplanes (that a big iron concept).

This is a nit. What difference does it make what name you hang on
it?...especially since the 4000/300 does indeed have a backplane...

> 2) Nuke vsbus.  On the {MV,VS}2000/3100/4000, just connect the
>    devices to mainbus0.  For example the VS4000/60 would be:
> 	mainbus0	at root
> 	le*		at mainbus?
> 	asc*		at mainbus?
> 	dz*		at mainbus?
> 	audioamd*	at mainbus?

This has rather serious implications for my work on the 4000/300. The KA670
has none of the things you mention, but it does have one SGEC (second
generation Ethernet controller) device and two SHAC (shared host access
controller) devices which live on the CPU card and require nothing in the
way of bus support, unlike the vsbus devices in the other VAXstations. At
Ragge's suggestion, I went about it by implementing a minimalist bus, the
mvbus, that does nothing except serve as a place to connect things. It would
be simple enough to do away with that and connect ze0 at backplane0, but is
that a Good Thing, and why?

> I know the above is a lot of work, but it really is required to 
> fully support the latter VAXen models.

Is it? How come? I'd really like to not have to overhaul the device driver
in the middle of writing it...