Macbook M2 displays stopped working correctly in 7.1.8-1

[sezaru]

I updated my system to kernel 7.1.8-1 from 7.1.5-2, right away I noticed something was wrong since the display would show up as UNKNOWN-1 instead of EDP-1. The main display couldn't get a proper refresh rate and my touchbar display also got black.

Version 7.1.5-2 works perfectly.

I asked Claude to take a look what changes were made to the drm code between 7.1.5-2 and 7.1.8-1 and he found these two commits:

• f580d09 — "drm: apple: Handle differences in surface positions between SoCs"
• 9f4a71c — "fixup! ... simplify surf/layer/plane handling" (Aug 11)

This series rewrites the DCP surface→layer→plane assignment (shared scanout
path), which would explain why both displays fail while the Touch Bar's own
driver (drivers/gpu/drm/adp) is unchanged. The refactor also changes the
default surface configuration when apple,iomfb-surfaces is absent — a plausible
mismatch for this SoC, though I haven't verified that's the actual mechanism.

So, I don't know if these are the real issue or if it is something else, but for now I pinned my kernel to ver 7.1.5-2.

[flokli]

Can you test with #532?

[sezaru]

Will do ASAP

[flokli]

Also test with asahi-7.1.10-1 please.