I have a very basic system with only the following packages installed
- xorg (xorg-server, xorg-server-utils, xorg-xinit, xorg-twm, xorg-xclock, xterm)
Before installing the nouveau or nvidia-340xx driver (for my GeForce 8500 GT card) I would like to try running the system using only the fallback video driver, just to see what it feels like.
What is the official/preferred fallback driver for xorg v1.18? According to Xorg wiki it is xf86-video-vesa but this information seems to be outdated ("Driver installation" section):
The vesa driver apparently doesn't work with xorg after v1.15:
The fallback drivers suggested on the thread quoted above are:
The modesetting driver apparently conflicts with xorg-server 1.18.0-4:
So the right fallback driver seems to be xf86-video-fbdev. Is this conclusion correct or have I missed somthing?
Assuming that xf86-video-fbdev is indeed the best fallback driver, how can you confirm that it is properly loaded on startup?
lspci command incorrectly identifies the driver as nouveau although noveau is not even installed on the system:
lspci -k | grep VGA -A 2 01:00.0 VGA compatible controller: NVIDIA Corporation G86 [GeForce 8500 GT] (rev a1) Subsystem: eVga.com. Corp. Device c793 Kernel driver in use: nouveau
pacman -Qi nouveau error: package 'nouveau' was not found
This probably happens because mesa and mesa-libgl were pulled as dependencies during xorg installation and they are usually used together with nouveau:
pacman -Qs nouveau local/mesa 11.1.1-1 an open-source implementaion of the OpenGL specification
The command below confirms that xf86-video-fbdev is really installed:
pacman -Qs xf86-video-fbdev local/xf86-video-fbdev 0.4.4-5 (xorg-drivers xorg) X.Org framebuffer video driver
Last edited by Kirkx (2016-01-22 13:56:32)
xf86-video-nouveau is a proper video driver, just like nvidia-340xx. I'm talking about a fallback driver, which is a generic driver that works with all GPUs but doesn't offer any advanced features (2D or 3D acceleration, etc) and normally would only be used when the proper driver fails to load for some reason.
I just want to use this basic generic driver for a while as part of Arch learning process.
https://www.archlinux.org/news/xorg-ser … available/ covers why the xf86-video-modesetting package is no longer needed.
Thanks. This answers Question #1 from my original post:
xorg-server 1.17.1 is now available
following upstream, xf86-video-modesetting is now provided with xorg-server package.
The answer to Question #2 still remains unclear (how can you confirm that the fallback driver was properly loaded at startup?). I have tried lsmod command. It is supposed to show which kernel modules are currently loaded, and it shows nouveau instead of xf86-video-modesetting, just like lspci command mentioned in the first post:
# empty line returned after this command lsmod | grep xf86 .....
lsmod | grep nouveau nouveau 1343488 1 mxm_wmi 16384 1 nouveau wmi 20480 2 mxm_wmi, nouveau video 24576 1 nouveau ttm 81920 1 nouveau drm_kms_helper 106496 1 nouveau drm 282624 4 ttm, drm_kms_helper, nouveau i2c_algo_bit 16384 1 nouveau button 6384 1 nouveau
As mentioned before xf86-video-nouveau is not even installed on the system (although packages mesa and mesa-libgl are installed and they might be considered related to nouveau).
nouveau.ko.gz is the kernel driver and is provided by the linux package and is what is being listed in lsmod.
nouveau_drv.so is the xf86 display driver provided by the xf86-video-nouveau package.
You can check Xorg.0.log which xorg driver was loaded.
Xorg.0.log is located somewhere in the dotfiles, unless you run X as root.
as loqs said, the xorg driver is not a kernel module, and the nouveau module that you see is necessary for 3D acceleration (which xf86-video-modesetting utilizes through GLAMOR)
how can you confirm that the fallback driver was properly loaded at startup?
It's not loaded at startup, it's use by Xorg, and will be in the Xorg logs.