Subject: Re: Fixes for TGA driver in XFree86
To: Michael Kukat <michael@unixiron.org>
From: Roland C. Dowdeswell <elric@imrryr.org>
List: port-alpha
Date: 11/29/2004 20:11:09
On 1101455319 seconds since the Beginning of the UNIX epoch
"Michael Kukat" wrote:
>

>If this really works, and if i find the time, i even would try to add working
>support for the PowerStorm 4D20, which is 24bit, and currently "just" has
>palette problems, but i didn't check further. Besides those evil color
>problems, the card seems to work okay. And as all those TGAs are based on the
>same chipset, i assume that fixing those DAC problems should enable using all
>TGA models. I can just test with old TGA, 8bit TGA2 (PBXGB-AA) and 24bit TGA2
>(PBXGB-CA?).

The 4D20 should work, I added support for it years ago.  I do not
recall any pallette issues that I didn't address, and I used the
card for about a year on my primary workstation (a PWS433au.)  I
don't think that I got around to accelerating it, though.  If you
are looking at XF86, you might consider taking a peek at the code
in the kernel which supports these cards:

	sys/dev/pci/tga.c
	sys/dev/pci/tga_conf.c
	sys/dev/ic/bt485.c
	sys/dev/ic/bt463.c
	sys/dev/ic/ibm561.c

The three RAMDACs are relatively different (last three files.)

I generally prefer the kernel approach since I don't like having
to let XF86 grovel my hardware---it's bad for security, and you
have to have kernel level support for the TGA (not TGA2) cards
since they have no text modes and the kernel needs to provide a
console...  So, whatever happens it is important that XF86 does
not mung up the cards in a way that confuses the kernel and not
just when it exits cleanly since it often doesn't.

--
    Roland Dowdeswell                      http://www.Imrryr.ORG/~elric/