[coreboot-gerrit] Change in coreboot[master]: drivers/intel/dptf: Add OEM variables support

[Tim Wawrzynczak (Code Review)]

Attention is currently required from: Furquan Shaikh, Justin TerAvest, Sumeet R Pawnikar, Todd Broch, Aaron Durbin, Patrick Rudolph, Karthik Ramasubramanian.
Tim Wawrzynczak has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/50127 )

Change subject: drivers/intel/dptf: Add OEM variables support
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Patch Set 1:

(3 comments)

File src/drivers/intel/dptf/dptf.c:

https://review.coreboot.org/c/coreboot/+/50127/comment/6b676b82_b7dfab14 
PS1, Line 129: DPTF_DEVICE_HID_EISAID
If this is the correct _HID, then I think you'll also need a `_UID` of 0 for the DPTF device itself, and a `_UID` here of 1 since they share this _HID.

https://review.coreboot.org/c/coreboot/+/50127/comment/779e3871_6fc55a3a 
PS1, Line 128: 	if (CONFIG(DPTF_USE_EISA_HID))
             : 		acpigen_emit_eisaid(DPTF_DEVICE_HID_EISAID);
If `DPTF_USE_EISA_HID` is not defined, then there will be an invalid `_HID` object here. If it's only supported by newer DPTF implementations, then it'll have to be the EISA type.

https://review.coreboot.org/c/coreboot/+/50127/comment/d8847656_ea152a7f 
PS1, Line 248: 	acpigen_write_package(6);
             : 	acpigen_pop_len(); /* Scope */
This is just an empty package