Subject: Re: PMAG-F console driver woes
To: None <port-pmax@netbsd.org>
From: Henry R. Bent <henry.bent@oberlin.edu>
List: port-pmax
Date: 03/29/2002 11:27:20
Toru Nishimura wrote:
>
> Although I can not provide any solution for you...
>
> Henry R. Bent <henry.bent@oberlin.edu>asked;
>
> > px0 at tc0 slot 1 offset 0x0: 3D, 5x2 stamp, 24 plane, 128KB SRAM
> >
> > Is the SRAM statement really correct?
>
> I guess so. The SRAM is used for i960 local memory as well as
> command storage which holds request/reply between CPU and i960.
Okay, that makes sense. Still seems a tad on the small side, but I suppose
it's fine for what it has to do.
>
> > I have 4 memory modules on the board,
> > so does that really mean they're only 32K each?
>
> It sounds like PX video memory, which is independent from and inaccessible
> from CPU.
That's what I was talking about: the memory modules on the PMAG-F itself.
Sorry for the confusion.
>
> > But on to the bigger problem. The console driver gets somehow out of sync
> > with scrolling lines. For instance,
>
> PX 2D/3D video card was sorta enginneered monster of that time. It was a
> pretty complex device built with a lot of hardwares even though it was
> a product of "(then-) maturing RISC age." Andy might have solutions for > you.
Yeah, it does seem to be a little bit of overkill for standard graphics in X,
and I don't even use anything but the console most of the time :-) Although
I'm being very tempted to put it in a machine with either Ultrix or OSF/1 and
see how the accelerated X server is. I'm curious to see the speed of the 3D
acceleration provided by the i860 and how it (in my /260) stacks up to my SGI
Iris Indigo w/an XS24-Z board.
>
> > Another quick ignorant question: how easy/hard would it be to have this driver
> > recognize that the card takes up three slots? Isn't it using all 3 for I/O?
> > I mean so that it would say something like "px0 at tc0 slot 1 2 3" at bootup.
>
> PX consumes a single TC option card _address range_ although it might
> consume 3 or 2 option card _physical space_.
Oh, okay. I went over this again in my mind and it made a little more sense:
it's not like having the card in two slots is suddenly going to make the TC
bus operate at 50MHz :-P
--
Henry Bent henry.bent@oberlin.edu
Want the Stars Productions http://www.wtsp.org