Screen tearing seen on Lenovo platforms with ADL-P
When testing with Fedora we're seeing screen-tearing on our Alderlake-P based systems (X1 Carbon G10 and X1 Yoga G7) The issue goes away when PSR2 selective fetch is disabled I confirmed we're using the C0 step silicon which I believe should support this. I've tested with the 5.17.0 drm-tip kernel
One note as it's particularly strange - we don't see the problem on Ubuntu, but do on Fedora (I've not tested with other distro's). I've confirmed this with exactly the same kernel, configuration and Intel firmware and can't make sense of it (the kernel was built on the same machine - once with make bindeb-pkg, once with make binrpm-pkg)
[root@x1carbon10 banther]# cat /sys/kernel/debug/dri/0/i915_edp_psr_status Sink support: yes [0x03] PSR mode: PSR2 enabled Source PSR ctl: enabled [0x80000299] Source PSR status: SLEEP [0x30000112] Busy frontbuffer bits: 0x00000000 Frame: PSR2 SU blocks: 0 0 1 0 2 0 3 0 4 0 5 0 6 0 7 0 PSR2 selective fetch: enabled
As a note, ubuntu has the same except Source PSR ctl: enabled [0x80000236] Source PSR status: SLEEP [0x30000100]
dmesg.log from the system - not seeing any errors reported (note - no idea why all the evbug reports - that's unique to running drm-tip and shouldn't have anything to do with the display issue....)
Happy to collect any information or try any debug if that would help
Mark