Subject: PMAG-AA frame buffer woes
To: None <port-pmax@NetBSD.ORG>
From: maximum entropy <entropy@zippy.bernstein.com>
List: port-pmax
Date: 04/01/1997 20:57:57
Greetings,

I've got a DECstation 5000/120 with PMAG-AA monochrome frame buffer.
The machine runs NetBSD (1.2 and recent -current kernels) just fine
with a serial console, but the frame buffer raster console seems to
not work at all.  The first few messages from the bootstrap (kernel
sizes and start offset) print OK and then the display goes haywire.
The machine does actually boot fine, and I even managed to get X
working by booting "blind" on the console and then running startx from
another terminal (but oddly the only X server that seemed to work was
Xcfbpmax...or is that expected because the display depth is 8?)

Because X works, I'm guessing the problem is not in the mfb
framebuffer code.  Likely sources of the problem seem to be the 1-to-8
raster mapping code in
/usr/src/sys/dev/rcons/raster_op.c:raster_op_noclip(), or maybe
something in raster_text.c:raster_textn() ... but staring at this code
hasn't got me very far and this is basically just wild guessing on my
part.

I looked through the archives for this list, and although a few people
have reported the same problem, I wasn't able to find a solution.

Any advice on getting a working text console would be greatly
appreciated.  If no one currently involved with NetBSD/pmax
development has a PMAG-AA, I have a spare I could donate for testing.

cheers,
entropy

--
entropy -- it's not just a good idea, it's the second law.