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How can I check if KMS is enabled in my kernel? I've compiled mine with KMS radeon modeset defaulting to 1, but I still suspect that it is not enabled.


aatiis@aiur ~ $ dmesg | grep drm
[drm] Initialized drm 1.1.0 20060810
[drm] Initialized radeon 1.33.0 20080528 for 0000:01:05.0 on minor 0
[drm] Setting GART location based on new memory map
[drm] Loading RS780 CP Microcode
[drm] Resetting GPU
[drm] writeback test succeeded in 1 usecs


aatiis@aiur ~ $ glxinfo | grep render  
IRQ's not enabled, falling back to busy waits: 2 0
direct rendering: Yes
OpenGL renderer string: Mesa DRI R600 (RS780 9612) 20090101  TCL

aatiis@aiur ~ $ sudo grep -i kms /var/log/Xorg.0.log
[    57.201] (II) [KMS] drm report modesetting isn't supported.
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up vote 2 down vote accepted

An easy test is this. Start an X session, then switch to a virtual terminal. If there's a slight delay, like the screen darkening for a second or so, KMS is NOT enabled. If it's near instant, it's almost certainly working.

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is there any way to do it without X? I'm trying to install wayland – bobbaluba Oct 6 '12 at 4:24

Kernel modesetting for radeon driver is supported after kernel version 2.6.31. If you have the driver with the version of later, you will be able to see a line that says "radeon kernel modesetting enabled." in dmesg log. Please check if dmesg contains any string with "modesetting."

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