Comment 66 for bug 1958191

I think there are potentially 4 or 5 different bugs that all result in forms of "flickering" on Intel graphics:

- One related to panel self-refresh (i915.enable_psr), this one has been around for a while, predates 22.04. I think it even predates 20.04
- "Kaleidoscope patterns" flickering, apparently memory other than the framebuffer is being displayed, or it's read from the wrong offset. This eventually leads to a crash in the iris Mesa driver. May not be kernel related. Personally I've only seen it happen in Xorg sessions, not Wayland. Freedesktop bug: #6341
- The one discussed above: in this case, flickering starts with the cursor in specific positions. Related to the I/O memory management unit (intel_iommu), new in 22.04.
- The issue solved by i915.enable_dc=0 + intel_idle.max_cstate=2, as some people reported here. However, for me (and also @kjur above) these options didn't solve the flicker, but intel_iommu=off did. So these are separate issues

For those whose issue is solved by enable_dc=0 + max_cstate=2, it would be worth trying i915.enable_psr=0 alone, without the other workarounds, to ascertain if it's the same issue or a different one

- And there's yet another one related to framebuffer compression (i915.enable_fbc)