Tim Wawrzynczak has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/41884 )
Change subject: drivers/intel/dptf: Add current participant Devices to DSDT ......................................................................
Patch Set 10:
(1 comment)
https://review.coreboot.org/c/coreboot/+/41884/10/src/drivers/intel/dptf/dpt... File src/drivers/intel/dptf/dptf.c:
https://review.coreboot.org/c/coreboot/+/41884/10/src/drivers/intel/dptf/dpt... PS10, Line 125: acpigen_write_device("TFN1");
It is required only if active cooling is desired. […]
So the way this implementation works is during DSDT injection, it writes out a minimal device definition (including a _STA that will indicate it's unavailable if it's not used in any policy). This makes things easier in later patches when we're writing helper methods, we can just assume that those devices exist and we won't have any unhandled references. It does add a small amount of bloat to DSDT if devices are unused. All of the configurable stuff (i.e, policies) are written into SSDT.