Plug & Play Support for RadeonHD



Introduction:

The Freedesktop group is currently implementing Plug and Play support for the radeonhd driver, the open source driver for ATI graphics cards. Unlike the proprietary fglrx driver it offers good xinerama support and is available for multiple operating systems like Linux and FreeBSD.

Plug and Play support will be especially useful for notebooks. You will simply be able to plug in an external monitor on the fly and use it, f.i. to show your photos on a slide projector or on TV. No more preconfiguration with xorg-configure, xorgconf or SaX2(OpenSuse) will be necssary. Up to now you had to create and then often manually edit an xorg.conf in order to restart your X-server. With plug and play detection X should even start without an xorg.conf. Your screen configuration can then be customized by tools like krandrtray, or the console tool xrandr.



current problems with plug & play support - the radeonhd rescue packages for OpenSuSE 11.2.

To test the plug and play capability of your driver you may want to use a minimal or no xorg.conf. However on some machines the current level of plug and play support may trigger undesirable errors; f.i. my integrated screen stayed black, my external screen was out of sync after updating to xorg-x11-driver-video-radeonhd-1.2.5_20090901_f7ad938-1.1. This is the version shipped by default with OpenSuSE 11.2, Milestone 7. If you are using OpenSuSE 11.1 or 11.0 and feel adventurous then you may install the newest Xorg and radeonhd by the following commmands:


  zypper ar http://download.opensuse.org/repositories/X11:/XOrg/openSUSE_11.1/ Xorg-newest
  zypper dup -r Xorg-newest
  

If you experience problems you should report an error at freedesktop.org. You may test without an /etc/X11/xorg.conf or even better with this minimal xorg.conf. Attach your /var/log/Xorg.0.log to the bug report. Basically preconfiguring an xorg.conf by tools like SaX or simply re-using your old xorg.conf should resolve the issue. However this is not the case for the driver version stated above.

The basic rescue action for this driver build or when having OpenSuSE 11.2, Milestone 7 installed is to use framebuffer mode instead of radeonhd by simply copying /etc/X11/xorg.conf.install to /etc/X11/xorg.conf.

However the usage of framebuffer mode will pose a regression since it offers no hardware acceleration and in the current state no xinerama support. That is why you may want to downgrade your radeonhd from Milestone 7 to Milestone 6 so that it becomes usable again. I have created an own x86_64 - xorg-ancient repo for this purpose:


  zypper ar http://repos.elstel.com/xorg-anc Xorg-anc
  zypper mr -p 20 Xorg-anc
  zypper dup -r Xorg-anc
  

Unfortunately the repo currently only provides packages for the x86_64 architecture. If you still have an i586-image of Milestone 6 residing on your computer please write me a mail to estellnb@elstel.org so that we can add i586 support

If you should need the downgrade and want to test whether current versions of radeonhd have improved there is a simple way to keep the old working driver in a directory of your choice so that you can update xorg & radeonhd without any hazard: Copy the content of the /usr/lib64/xorg/modules or /usr/lib/xorg/modules to a directory of your choice say /var/tmp/xorg_modules and add the following line to the files-section of your old xorg.conf:


  ModulePath "/var/tmp/xorg_modules"
  ModulePath "/usr/lib64/xorg/modules/updates,/usr/lib64/xorg/modules"
Then your old xorg.conf will always use the old driver and hence work after any kind of update. At me the content of this directory is made up by the following packages: x11-input-wacom-0.8.3-5.4, xorg-x11-driver-input-7.4-37.1, xorg-x11-driver-video-7.4-81.1, xorg-x11-driver-video-radeonhd-1.2.5_20090901_f7ad938-1.1, xorg-x11-driver-virtualbox-ose-3.0.4-5.1, xorg-x11-server-7.4-51.4


use your notebook with a docking station: preconfiguring xinerama mode with your xorg.conf

Using notebooks with a docking station is becoming more and more popular: get the mobility of a notebook and the comfort of a standalone PC. With Linux you can dispense buying an own docking station and simply plug USB-mouse, USB-keyboard and external monitor into your notebook to get the usage comfort of a standalone PC. Now Xinerama mode allows you to use both screens in parallel to get one big display.

For the usage of your notebook with a docking station you want to preconfigure xinerama mode; i.e. configure which screen is at the left, which one at the right; which monitor is to become the primary screen offering your task bar and what the respective screen sizes (font size!) are. That is why you will desire an appropriately set xorg.conf. Nonetheless the settings should also be applied if you first boot your notebook and then, afterwards dock it at your dockingsatation. Post a comment at the respective feature request to show your support for this!

Novell is currently planning to fully crop the support of SaX2 and xorg.confs. Vote against it at bugzilla.novell.com!

Here are example xorg.confs configuring xinerama mode for radeonhd-1.2.5_20090506_4be5f71-7.46 and radeonhd-1.2.5_20090901_f7ad938-1.1




*** OpenSuSE 11.2: beta testing ***

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