https://bugzilla.kernel.org/show_bug.cgi?id=39672

Summary: [r280] Black screen on PPC with digital monitor on radeon / Cannot find any crtc or sizes Product: Drivers Version: 2.5 Kernel Version: 3.0.0-rc6 Platform: All OS/Version: Linux Tree: Mainline Status: NEW Severity: high Priority: P1 Component: Video(DRI - non Intel) AssignedTo: drivers_video-dri@kernel-bugs.osdl.org ReportedBy: rechner@vlado-do.de Regression: No

Created an attachment (id=66132) --> (https://bugzilla.kernel.org/attachment.cgi?id=66132) syslog from system without video output

Testing Kernel 3.0.0 (rc6 from Debian experimental) I encountered a problem with (DVI) display detection - the screen goes blank when trying to activate KMS. From syslog:

[drm:radeon_add_legacy_connector] *ERROR* DVI: Failed to assign ddc bus! Check dmesg for i2c errors.

[drm] DDC: no ddc bus - possible BIOS bug - please report to xorg-driver-ati@lists.x.org

No connectors reported connected with modes [drm] Cannot find any crtc or sizes - going 1024x768

To me this looks quite similar to #23222.

With a VGA monitor the screen does not go blank, but I still don't get the login window in KDM (?).

I'm using Ubuntu 11.04 and with a self-compiled 2.6.39-rc7 kernel I have working KMS (even though direct rendering does not work, as reported on https://bugs.freedesktop.org/show_bug.cgi?id=37169 ).