[SOLVED] Use the nouveafb as framebuffer and the nv driver for Xorg

marcs · 2011-06-28 01:08:17

Hi! I'm using Arch on a JAMMA Arcade cabinet (one of those old arcade cabinet) so i need some strange video resolution to suit my needs.

The best option is a 640x240 @ 60Hz vertical and 15Khz horizontal. Arcade screens must have an horizontal frequency of 15Khz or I'll fry my screen! Luckily i use a card called J-PAC that cut off the video signal if is not 15Khz.

With Xorg there's no problem if i use the nv driver, using this Modeline do the trick:

# 640x240x60.00 @ 15.240kHz Perfect screen mode for Xorg
Modeline "640x240x60.00" 12.192000 640 656 720 800 240 244 248 254 -HSync +VSync

I've found this modeline using a little program called umc: http://aur.archlinux.org/packages.php?ID=27550

Instead Xorg crash randomly if I use the same modeline with the nouveau driver, sometimes at startup, other times during the Xorg session. I use some "no edid" options that let me use strange video resolutions but i don't know if this is bothering the nouveau driver or not, surely it isn't bothering the old dear nv driver.

BUT WAIT!!!!

The nv driver can be loaded only if the nouveau driver is not loaded!

So if I use the nv driver for Xorg i lose the nouveafb, and the nouveafb is the only one that works for me 'cause i can't force a non standard video resolution like 640x240@60hz on vesa and uvesafb! At least this is what i've learned from the docs, tell me if i'm wrong: http://git.kernel.org/?p=linux/kernel/g … vesafb.txt

For now the only thing that make the framebuffer works at 640x240 is this: video=DVI-I-1:640x240@60eMm but this kernel command works only with KMS and the nouveafb.

So my question is, can i use the nouveau driver for framebuffer only ? and the NV driver for Xorg ?

Or there is another approach ?

I remind you that i need a resolution of 640x240 both on the framebuffer and on Xorg, i'm using an old GeForce4 Ti4600 that is supported by nouveau (chip NV20).

Thank for your patience and your time.

Bye for now.

Last edited by marcs (2011-06-28 12:05:13)

Gusar · 2011-06-28 11:32:58

I think what you should be concentrating on is getting that resolution working with nouveau. Have you made a report to the nouveau guys?

marcs · 2011-06-28 12:04:29

Hi

It seems (well for now all is stable)... that now I got a more stable situation loading the nouveau module directly from initramfs.
I'm guessing that now this is the solution, is the only thing i've changed, now fbsplash works also on start. (yay!)

For solution documenting, you can do the same doing like this:

1. edit the /etc/mkinitcpio.conf file with nano, vim or whatever.
2. Add at the MODULES="" the nouveau module like this: MODULES="nouveau"
3. Add the modprobe.conf file to the FILES="" line, like this: FILES="/etc/modprode.d/modprobe.conf"

4. OPTIONAL: If you are using fbsplash like me you must add at the HOOKS also the fbsplash script like this: HOOKS="base udev fbsplash ..." : look here: https://wiki.archlinux.org/index.php/Fbsplash

5. OPTIONAL: On an arcade cabinet the best text font must be tiniest possible like an 8x8. I'm using cp865-8x8 wich is much better than Agafari-16 that is good for high resolutions. To use this console font as soon as possible you can add also consolefont to the HOOKS like, like this: HOOKS="...[stuff before] consolefont"; look here: https://wiki.archlinux.org/index.php/Fo … fault_font.

6. Then you must remake the initramfs images doing this: mkinitcpio -p kernel26 (or whatever kernel you wan't to use as a model, i'm using kernel26-fbcondecor).

To use fbcondecor, you can find the kernel26-fbcondecor package from AUR: http://aur.archlinux.org/packages.php?ID=15603 (please support this package)

Xorg seems very stable for now. I'm using the nouveafb framebuffer with fbsplash on an old arcade cabinet and that's some fine eye candy man!

PROBLEM SOLVED!

BUT WAIT!!!
I have to know now what's the difference between loading nouveau from initramfs... I don't know if the problem is related to nouveau or KMS or fbcondecor, or fbsplash, or the kernel I'm not so good to know that.

Now can any kernel guru tell me what is the basic difference by loading a module from initramfs instead making the kernel load it, a part the fact that is loaded a bit earlier from initramfs. There are also difference between memory areas ?

I'll send a bug report and how to reproduce it, but i guess that my configuration is a bit out of the mainstream...

Thank to anyone that have taken a look at this post.

daneel971 · 2011-06-28 14:46:53

marcs wrote:

Hi! I'm using Arch on a JAMMA Arcade cabinet (one of those old arcade cabinet)

Post a picture of it, please

marcs · 2011-06-28 16:28:35

daneel971 wrote:

marcs wrote:
Hi! I'm using Arch on a JAMMA Arcade cabinet (one of those old arcade cabinet)
Post a picture of it, please

Here's is a picture of the fbsplash i've made with my cabinet version of Arch, i called it ArchAde.
http://95.110.193.65/~emarcs/shutdown.jpg

And this is the frame buffer. Advmame and SDLmame work only with Xorg. Advmame doesn't support the nouveafb. But i have a minimal Xorg installation with no window manager.
http://95.110.193.65/~emarcs/fb.jpg

Follow image posting rules -- Inxsible

daneel971 · 2011-06-29 06:04:37

"Amazing" is the word... ^^

rwd · 2011-06-29 10:58:19

wow.. nice one!

daneel971 · 2011-06-29 19:57:19

Marcs, you made me really curious
Please, tell us something about that machine: how did you build it, what kind of hardware it has, what did you do to run linux on it, if you can ship one to us etc...

Inxsible · 2011-06-29 20:07:37

The thread is solved and is going off topic.

Closing....

Arch Linux

#1 2011-06-28 01:08:17

[SOLVED] Use the nouveafb as framebuffer and the nv driver for Xorg

#2 2011-06-28 11:32:58

Re: [SOLVED] Use the nouveafb as framebuffer and the nv driver for Xorg

#3 2011-06-28 12:04:29

Re: [SOLVED] Use the nouveafb as framebuffer and the nv driver for Xorg

#4 2011-06-28 14:46:53

Re: [SOLVED] Use the nouveafb as framebuffer and the nv driver for Xorg

#5 2011-06-28 16:28:35

Re: [SOLVED] Use the nouveafb as framebuffer and the nv driver for Xorg

#6 2011-06-29 06:04:37

Re: [SOLVED] Use the nouveafb as framebuffer and the nv driver for Xorg

#7 2011-06-29 10:58:19

Re: [SOLVED] Use the nouveafb as framebuffer and the nv driver for Xorg

#8 2011-06-29 19:57:19

Re: [SOLVED] Use the nouveafb as framebuffer and the nv driver for Xorg

#9 2011-06-29 20:07:37

Re: [SOLVED] Use the nouveafb as framebuffer and the nv driver for Xorg

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