My ViewSonic G220fb is immediately switched to 1600x1200@85 with KMS enabled. As soon as this happens, the entire contents start to massively flicker. Once in Xorg, the flickering continues. It also continues if I switch to 1280x1024@85, though both 1600x1200@75 and 1280x1024@75 work just fine.
Without KMS enabled, I can use both resolutions in Xorg @85 without any flickering.
You can clearly see the flickering in this video:
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Xorg.0.log file with KMS enabled
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xrandr --verbose with KMS enabled.
This same combination of monitors works fine with an HD3450 and drm-next. No flickering at @85. Attaching Xorg.0.log file.
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Xorg.0.log file with KMS enabled on HD3450
FYI, this is still an issue as of 18.104.22.168, and also happens with an x850.
Is this still an issue with the new pll code in drm-radeon-next?
firstname.lastname@example.org, no with no flickering :-)