Subject: Re: color status
To: David Huggins-Daines <bn711@freenet.carleton.ca>
From: Michael R. Zucca <mrz5149@acm.org>
List: port-mac68k
Date: 02/08/1999 23:07:37
At 11:21 PM -0500 2/7/99, David Huggins-Daines wrote:
>On Sun, Feb 07, 1999 at 08:20:12PM -0500, Michael R. Zucca wrote:

>I've got a Q630 (maclinux.plcom.on.ca) and I'm probably going to buy
>another one for development, since due to the IDE, they are quite a bit
>faster than other Macs (or even PCs) with the same CPU speed.  I've
>been meaning to work on porting valkyriefb.c to m68k for a while.

I'm surprised you guys haven't already ported valkyriefb. The only thing you
needed was the bas address of the controller and the DAC. The rest of the
chip functions just as it does on the PowerMacs.

Think about the PowerMacs it lives in. They are essentially souped up 630
motherboards with a PowerPC accelerator. :)

>I can help you with testing and debugging Valkyrie support in NetBSD
>if I get another Q630 (the current one will be running a web/FTP mirror
>for Linux/mac68k so I can't dual-boot it).

Support on NetBSD will be somewhat more limited than valkyriefb at first.
We just don't have the right API to do the stuff XF68k fb devices
are able to do...yet.

The other thing that bugs me is that we really need a way to *read* the
current timings, if possible. During the device match/attach phase I
need a way to figure out what mode we booted into. Unfortunately, the
video clock on the Valkyrie is programmed via the CUDA and I don't think
anybody has found a programmatic way to read values. I know Paul M. from
the ppc port had to hook up a scope to get the right values for the
first cut of the driver.

We could force the machine into a particular resolution but that is kind
of obnoxious since video initialization doesn't occur until match/attach.
I've had ideas of an "early" video initialization to put the controller in
a known mode before text even makes it onto the screen but I don't know
whether we want to do something like that.

>Have you found its I/O base?  (it's configured by Open
>Firmware on PPC, so there's not much if anything to go on there -
>however, in some system profilers on MacOS, it shows up as a NuBus
>device, though I haven't figured out exactly how that relates to
>physical memory space...)

I'm probably going to catalog all the info I know at some point but just so
you know:

Controller: 0x50f2a000
DAC: 0x50f24000

Once you know that, you should be able to port valkyriefb in one evening.

Enjoy!


_______________________________________________________________________
 Michael Zucca - mrz5149@acm.org - http://www.mdc.net/~mrz5149/
 "I will choose a path that's clear. I will choose Freewill. "
  --Rush, Freewill
_______________________________________________________________________