I'm running an AMD Radeon R9 380 (Tonga, GCN 1.2) on Ubuntu 24.04-based
system with kernel 6.17.0-14-generic.
I’m experiencing HDMI resume instability when DC is enabled. After
suspend-to-RAM (deep), the system wakes but the screen returns either
blank or with corrupted output. Input devices respond (cursor moves),
but the session is unusable and requires forced reboot.
The issue is completely resolved by adding:
amdgpu.dc=0
to the kernel parameters.
This reminds me of historical Tonga/DC regressions such as bug #1784156,
where disabling DC restored proper output detection and signal behavior.
Given that Tonga (GCN 1.2) is a legacy architecture, it may not be
receiving the same level of DC resume-path validation as newer RDNA
GPUs. This might indicate a DC-specific regression affecting older GCN
display pipelines during resume.
I can provide additional logs (dmesg before/after suspend, drm debug
logs, etc.) if needed.
--
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.
https://bugs.launchpad.net/bugs/1784156
Title:
[regression][amdgpu] analog output stops working on R9 380/Tonga Pro
after upgrading to Ubuntu 18.04
To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1784156/+subscriptions
--
ubuntu-bugs mailing list
[email protected]
https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
