| Summary: | On Ubuntu Bionic with kernels 4.15 and above, RX480 Displayport outputs don't work (dmesg reports "not connected") | ||
|---|---|---|---|
| Product: | DRI | Reporter: | Pixie <icekhaos> |
| Component: | DRM/AMDgpu | Assignee: | Default DRI bug account <dri-devel> |
| Status: | RESOLVED MOVED | QA Contact: | |
| Severity: | normal | ||
| Priority: | medium | CC: | harry.wentland |
| Version: | unspecified | ||
| Hardware: | x86-64 (AMD64) | ||
| OS: | Linux (All) | ||
| Whiteboard: | |||
| i915 platform: | i915 features: | ||
| Attachments: | |||
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Description
Pixie
2018-05-30 09:12:20 UTC
Please attach the dmesg output as well as the Xorg log file. Alright. Will do in a couple hours, when booted on newer kernels. Currently booted on an old one, probably good to include it as well for comparison's sake. Google turned up nothing on this issue either, so I came here. Would a Displayport to DVI converter have anything to do with recent changes? Can you narrow down the regression or better yet bisect? If instructed how, I would definitely be willing to bisect. Power went out, fell asleep, no xorg logs during the day. Sorry for the delay, a working log/dmesg combo on 4.14.35 coming up shortly, for reference. This breaks on any kernel 4.15 and above, by the way. Decided to report it against whatever is present in 4.17, since the issue still persists there. And if I can get rc4 to install, I'll test that and provide the logs from that. Created attachment 139875 [details]
dmesg log on a working setup (kernel 4.14.35, latest stable mesa)
Created attachment 139876 [details]
Xorg log on the same functional 4.14.35 setup.
Logs from working software submitted. Booting promptly into a newer kernel and salvaging logs from there. Nope, fell flat on its face. rc1 logs coming shortly. Created attachment 139877 [details]
dmesg from a broken 4.17-rc1 setup; look here for the errors
Created attachment 139878 [details]
Xorg log on the broken 4.17-rc1 setup
The broken Xorg log doesn't even seem to acknowledge the monitor exists through a quick grep.
Seems somewhere between what looks like versions 3.19 and 3.25. Gonna guess 4.15 has an earlier version; gonna fetch logs from that shortly. Seems like I had the right idea. 4.15 runs amdgpu 3.23. May install a Mesa git version from a PPA after this to check. Really want the new kernels, so I'm probably gonna do that right away after posting the two logs. Created attachment 139879 [details]
Broken dmesg on 4.15
Created attachment 139880 [details]
Broken Xorg log on 4.15
That Git install doesn't seem to have changed anything visible. Doesn't show in logs either, which is weird. Running glxgears gives me a GL version of 3.1 Mesa 18.2.0-devel, that the one I'm looking for? Does amdgpu.dc=0 on the kernel command line work around the problem? Where would I enter that? on the kernel command line in grub. Sorry for the late reply; yes, amdgpu.dc=0 fixes it. What does that even do? -- GitLab Migration Automatic Message -- This bug has been migrated to freedesktop.org's GitLab instance and has been closed from further activity. You can subscribe and participate further through the new bug through this link to our GitLab instance: https://gitlab.freedesktop.org/drm/amd/issues/406. |
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