Dual-Head without GUI

yeelong · 2012-06-01 17:59:16

hi, is there a way to setup two monitors (1 DVI,1HDMI on the same ATI-radeon) before start GUI? first its annoying,but of course not that important when booting the system and the output appears on both screens and second, more important, when i'm programming (basic C++) and don't require GUI i want to use both screens.

moreover i had problems recently with KDE(fedora 17) and Cinnamon(Mint 13) to keep my screen settings. is it best to put xrandr --.... in rc.local to configure monitors?

Pres · 2012-06-01 18:26:23

A quick google search tells me this isn't possible:
http://superuser.com/questions/152492/i … e-in-linux
http://www.linuxquestions.org/questions … es-834757/

For an alternative, look into tmux. You can at least display two terminals side by side on one monitor. You could also consider configuring a lightweight tiling WM to give you a similar effect.

For xrandr, I just throw it in my .xinitrc file right above the line that starts the WM/DE.

ConnorBehan · 2012-06-01 18:52:51

You can make each monitor show a separate tty. Get /dev/fb0 and /dev/fb1 created using framebuffer drivers (e.g. the radeon DRM driver with modesetting) and then move consoles around with the con2fb program.

yeelong · 2012-06-02 15:08:17

tmux is a bless, i wish i had know it earlier! i've tought about a lightweight WM, but my hardware is pretty new and when i have to start an x-server i want at least a bit KDE-eyecandy :-)

so it is possible?! to enable KMS i've edited mkinitcpio.conf: MODULES="radeon" and added radeon to the module array in /etc/rc.conf according to the ATI-wiki page.
dmesg | grep drm:

[ 1.031994] [drm] radeon kernel modesetting enabled.
[ 1.032145] [drm] fb: conflicting fb hw usage radeondrmfb vs VESA VGA - removing generic driver

how do i get /dev/fb1 created? (/dev/fb0 is there already)

ConnorBehan · 2012-06-03 02:35:34

Oops... just realized the method I was thinking of only works with two cards. Sorry.

yeelong · 2012-06-03 11:59:09

Ok too bad.. do you think the problem itself is too hard or is it just not possible because its not interessting for most people and nobody programmed the driver to work that way? is it hard to programm something by yourself?

i have a second ATI card, pretty old but should still work... i just haven't managed it that the card is recognized by the OS! in windows 7 the card is recognized, but doesn't work either.
should i'll go on trying your method with the second card?

yeelong · 2012-06-03 13:07:06

i've inserted the second card (ATI RV516 Radeon X1300/X1550 Series) and /dev/fb0, /dev/fb1 are both created, but
dmesg | grep -i error output:
[drm:radeon_vga_detect ] *ERROR* VGA-2: probed a monitor but no|invalid EDID
[drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 128

ConnorBehan · 2012-06-03 20:20:35

I don't know the exact cause of that error, but you can try different combinations. Try a different monitor, try switching which card is primary and which is secondary, try switching between VGA and DVI, etc.

Also, if the primary card is giving you this error, you can try using a generic framebuffer driver for it. When I first did this, my r128 was primary and my radeon was secondary. I created /dev/fb0 by using the uvesafb driver on the primary and /dev/fb1 by using the radeon modesetting driver on the secondary.

Arch Linux

#1 2012-06-01 17:59:16

Dual-Head without GUI

#2 2012-06-01 18:26:23

Re: Dual-Head without GUI

#3 2012-06-01 18:52:51

Re: Dual-Head without GUI

#4 2012-06-02 15:08:17

Re: Dual-Head without GUI

#5 2012-06-03 02:35:34

Re: Dual-Head without GUI

#6 2012-06-03 11:59:09

Re: Dual-Head without GUI

#7 2012-06-03 13:07:06

Re: Dual-Head without GUI

#8 2012-06-03 20:20:35

Re: Dual-Head without GUI

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