Re: Panic at boot on 4/330 with cgfour and cgsix

[Brad Spencer <brad%anduin.eldar.org@localhost>]

Mouse <mouse%Rodents-Montreal.ORG@localhost> writes:

>>> I was using X on a cg4 back in the '80s.  Match SunOS's mmap offsets
>>> and I see no reason it wouldn't Just Work now.
>> Indeed, and the Xsun driver would handle this correctly ...
>
>>>> [...enable plane...]
>>> Maybe for text console.  But for X, I'd prefer to use the enable
>>> plane to support both 8bpp and 1bpp at the same time.
>> ... and probably did this as well - I didn't check the code when I
>> had a working cg4.
>
> The server I remember just presented two screens, an 8bpp screen and a
> 1bpp screen.  I don't think I ever used one that did the dual-depth
> thing.  When I was hacking on the cg14 ddx layer, I considered just
> doing an 8bpp screen and a 24bpp screen, but handling both visuals on
> the same screen, (a) I (correctly) expected would teach me more and (b)
> seemed likely to be more useful.
>
>> However, looking at the current source tree, we don't have either
>> Xsun or xf86-video-suncg4 (hmm, did the latter exist?) so we'll have
>> to put this together ourselves to work with modern X.
>
> I wouldn't even consider using "modern" X on hardware where it's not
> necessary.  I use it on i386 and amd64 because of the disaster video
> hardware is on the ports - but I run MIT X on my SS20s, because
> "modern" X, even if it were to run, wouldn't bring me much, if
> anything, over MIT X.
>

[snip]

Injecting some memories...

The zaphod mode, named for Zaphod Beeblebrox I think, of the "old" X
servers.  I ran it on a 4/110 with SunOS 4.x and with NetBSD a long time
ago on the same hardware.  That beast has a cgfour.  I also remember
beating on NetBSD a bit to get the bwtwo and cgfour talking at the same
time so zaphod mode would work.  That effort may be in a PR somewhere,
or in a email to port-sparc from 1996[1].  Something broke between
releases, as I think it just worked in NetBSD 1.x or 0.9 (or
something... it has been a long time ago).  I think I remember two
screens on one physical display and I think I remember being able to
move between them by programming a key in twm/tvtwm.






[1] - A quick look around some old archives I have suggests that I might
have a version of my patches that could be provided to someone.

-- 
Brad Spencer - brad%anduin.eldar.org@localhost