Great news. I'm looking forward to making it work under ubuntu PPC 10.04

str8bs: could you file an official Debian bug report against xserver-xorg-video-nouveau and tell everything you did to get it to work properly. It is of course great that you got it working, but it would be even better if it would get fixed upstream, so other users would be helped automatically in the same way. I just filed a bug report myself against the same package. I had a working nouveau driver before on my iMac G5 20, but lately, I experience problems. I now use the nv driver again.

http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=668828

linuxopjemac: Will do. It will be my first attempt at a bug report.
I posted in other thread as well, but this workaround solves the "half screen corruption/refresh" issue on mine. Disable hardware rendering/acceleration (3d Support).

Can be done two ways that I know of:
1. Via boot: command option:
2. Edit (nano) /etc/modprobe.d/nouveau.conf to include:

Taken from this wiki.
EditThe above works but as linuxopjemac pointed out in other thread, it also breaks video playback. IE: Minitube, FLVR, DVD

With hardware acceleration enabled: I wonder if the corrupt screen issue has something to do with how it is allocating/handling VRAM. Using lower resolutions seems to make it go away. I notice if logged in to Gnome classic, it does not go away, but improves. Also, if I change resolutions back and forth using xrandr, the area of "corruption" moves up or down on the screen.

Also an update on the boot: options I have been playing with:
This command works around the "phantom port" issue and forces Screen 0 to be the correct one when X is started. If I uninstall nouveau, my machine will boot fine with FBDEV using this same boot command. Also works with NV and KMS as Marty mentioned (Ubuntu)
However, it appears that the options in bold get reset to defaults when X starts. I think when NVenterVT is called. I haven't found a way to force them in X yet. I have tried other variations found on the net like: with the same results. I am searching for a way to make nouveau use the same options persistently when X starts.

To set resolutions in X, you have to also use an xorg.conf file. If you need directions, you can ask me. For generic help:
http://mac.linux.be/content/xorgconf-files

I will try your suggestion about the nouveau acceleration. I will keep you updated...I found out that using lower color depth (which can also be set in xorg.conf), he problem diminished...

str8bs: you saved my day !! This hack worked like a charm. Thanks a lot for this. I will also report it in the Debian bug report. Maybe they can implement this in the driver, like when this card is seen on PPC, that acceleration is switched off in a nouveau kernel config file. Once again, thank you very much!

linuxopjemac:
Glad it was useful. RE: Bug reports. I currently have trouble differentiating "bugs" from my own ignorance. Obviously, the CPU will work harder now, but at least we can see the whole screen.

RE: xorg.conf Sorry I wasn't more clear. I have experimented with xorg.conf but was searching alternate as, in my experience, using xorg.conf changes logs and leads to confusion (for me.)

I am able to set resolution and refresh rates in X on the fly using xrandr but not color depth. I have seen multiple threads related to nouveau and color depth and was hoping to find an easier solution.

May be goose chase, but I have read for similar situation on Intel based, GRUB has options "gfxmode=XresYres.. and gfxpayload=keep."

Side note not directed at anyone in particular: Kind of mind boggling that decision was made long ago to integrate nouveau into the kernel, yet it is SO hard to find documentation for nouveau. IE: What options can be set in nouveau.conf? I haven't found a wiki yet that details it. Rant over.

Ok, you helped me so nicely, I am going to try to help you now...

Let me get that straight, you want nouveau to work at 1280x1024 resolution with color depth 24 at 75 Hz ? You also want to disable DVI-I-1 and TV-1....I would try an xorg.conf file like this:




You might need an extra modeline to force X into 75 Herz, but normally nouveau will find these frequencies itself.

linuxopjemac:
Thanks so much for that. Lack of communication on my part. (..strange urge to listen to my old Ratt albums )
I managed that, but was trying to avoid xorg.conf completely.

Regarding the corrupt lower half of screen issue: In addition to the second workaround I mentioned in your "got MintPPC running on" thread, I think I have found a third workaround. Of course, this one requires xorg.conf.
I will confirm in my Debian7 install and update here and your bug report. Key seems to be using a square virtual entry in xorg.conf under display subsection. IE: Virtual 1280 1280

Question:
Bug report for the original blank screen issue: What should I file under? Kernel? It isn't really Xorg, because it happens with FBDEV, NV, and Nouveau due to KMS.

I would file it against xserver-xorg-video-nouveau, as that is the package that should work (it's the standard driver nowadays in Debian for nvidia cards). If the X maintainers think it should be sent to someone else, for example the debian-installer team, they can do so on their own volition...

I am interested in your third hack.

Nouveau Bug 668828 Corrupt/Incomplete Display Possible workarounds.

If you experience same and have other workarounds, update http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=668828 .

I have repeated the problem in MintPPC11 LXDE and Debian7 Gnome Classic. The following three workarounds solve on my hardware (in signature) for both installations.

Workaround 1: Disable hardware rendering/acceleration (3d support) This works BUT also breaks video playback. (IE: Minitube, FlashVideoReplacer.) Can be done two ways. Second is permanent.

1. This is without xorg.conf in use.
2. append to yaboot command
   Code:
   boot: Linux nouveau.noaccel=1 ...
3. Edit /etc/modrobe.d/nouveau.conf to include:
   Code:
   options nouveau noaccel=1

Workaround 2: Use xrandr to change modes to lower resolution and then back to desired.

1. This is without xorg.conf in use.
2. Open terminal and query available supported outputs and modes.
   Code:
   xrandr -q
3. Change to lower resolution mode.
   Code:
   xrandr --output DVI-I-1 --mode 800x600 --panning 800x600
4. Change back to desired resolution.
   Code:
   xrandr --output DVI-I-1 --mode 1280x1024 --panning 1280x1024
   No idea why the --panning option applies on mine.

Workaround 3: Create xorg.conf that disables disconnected outputs AND sets Virtual Desktop area to square of your resolution H size.

1. To disable disconnected ports, follow "Option B" directions on page 1 of this thread. EDIT 07-29-2012: Step one should only be necessary if you also have phantom port issues.
2. Set "Virtual" subsection to a square desktop size using your desired resolution H size.
   Code:
   Section "Screen"
       Identifier    "Default Screen"
       Device        "FX5200"
           DefaultDepth    24
              SubSection       "Display"
                Depth            24
           Virtual 1280 1280
              EndSubSection
   EndSection
   
   If I omit the "Virtual" entry or set it my actual display size of 1280 1024, the display corruption continues. When I make it square of my H size- 1280 1280, corruption issue disappears. EDIT: "Square" is irrelevant but works. ydim only needs to be increased enough to move corruption off screen.
   *NOTE- If you are using multiple displays simultaneously and not mirrored, this will likely create problems. Try larger Virtual such as 2560 2560.