Document the ACPI thermal zone pattern used across multiple mainboards
that implement five-level fan control via power resource state machines.
This pattern is used by 9 mainboards including Google Chromebooks
(beltino, jecht variants), Samsung stumpy, and Intel reference boards
(wtm2, baskingridge, emeraldlake2).
The documentation covers:
- Power resource state machine implementation
- Temperature management via PECI/SuperIO
- Active and passive cooling policies
- Critical FNP4._OFF no-op requirement for Windows compatibility
- Implementation variations and checklist for new boards
Initial framework generated by Cursor AI, heavily edited thereafter.
Change-Id: I4174a4552c97fb85a894f5362948d57057cacb81
Signed-off-by: Matt DeVillier <matt.devillier@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/89843
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Sean Rhodes <sean@starlabs.systems>
8cc8f219bf
