https://bugzilla.kernel.org/show_bug.cgi?id=42616
Summary: Radeon Kernel Mode Setting sets wrong mode Product: Drivers Version: 2.5 Platform: All OS/Version: Linux Tree: Mainline Status: NEW Severity: normal Priority: P1 Component: Video(DRI - non Intel) AssignedTo: drivers_video-dri@kernel-bugs.osdl.org ReportedBy: thomas.jones@utoronto.ca Regression: No
I have a Radeon HD 3470, connected to a Dell P2010H monitor via Display Port.
The monitor's native resolution is 1600x900, and everything works correctly with UMS, however if I use KMS I cannot use that mode, I can use at least 1024x768, 1280x1024, and 1152x864 with KMS, but no matter how I try I cannot get it to work in 1600x900. I have tried with the CVT timings, (reduced blanking and not) and with the ones provided in the monitor's EDID.
If I attempt to set any of those modes (the 1600x900) with KMS on the monitor claims that I'm using an unsupported mode. UMS works just fine though.
I'm running Fedora, and I don't think this is a regression in the kernel since I don't think this computer has ever worked with KMS.
Right now what I've done is I have set the kernel command line to boot with 1152x864 and KMS, then I tried to use xrandr to change modes and the monitor just complained.
dmesg doesn't seem to have anything useful to say, and neither does Xorg.0.log