<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - FirePro v8800 Failure to recognize DisplayPort signal" href="https://bugs.freedesktop.org/show_bug.cgi?id=106191#c11">Comment # 11</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - FirePro v8800 Failure to recognize DisplayPort signal" href="https://bugs.freedesktop.org/show_bug.cgi?id=106191">bug 106191</a> from <a class="email" href="mailto:francois.jacques@gmail.com" title="François Jacques <francois.jacques@gmail.com>"> François Jacques</a> <pre> The bug is caused by having both the audio signal and image simultaneously, it seems. After I added "radeon.audio=0" to the kernel argument list and rebooted, the video interface and the monitor concluded their signal handshake successfully (!) and I could switch the monitor to full res and, lo' behol', a 1440p image (!!). For future reference, should anyone have issues, try radeon.audio=0. If you were relying on the radeon for audio, look for an alternative, or use a DP-to-HDMI adapter and tolerate the lower resolution until the bug is fixed. ---- Googling on this specific symptom revealed multiple regressions on this matter before, it could be a new one or it's been lurking for a while. Which means either: - tons of dupes in the DRM bugs list wrt radeon and DP /w audio enabled and users don't know how to disable it. - all radeon users having switched their audio off - most radeon users gave up on their DisplayPort or their radeon-based card altogether (perhaps switching brand in the process, frustration kicking in) - it's a recent regression and I've been lucky to catch it before the kernel goes mainstream in major distros. I'll still provide a dmesg dump, this time with drm.debug=0x06 (0x06 any good? any prefered value?) by rebooting with audio back on and image gone.</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the assignee for the bug.</li> </ul> </body> </html>