[L] Change in coreboot[main]: acpi: Move acpigen_write_OSC_pci_domain to Xeon-SP

[Nico Huber (Code Review)]

Attention is currently required from: Arthur Heymans, Christian Walter, Cliff Huang, Felix Held, Johnny Lin, Jonathan Zhang, Lance Zhao, Lean Sheng Tan, Patrick Rudolph, Shuo Liu, Tim Chu, Tim Wawrzynczak.

Nico Huber has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/81652?usp=email )

Change subject: acpi: Move acpigen_write_OSC_pci_domain to Xeon-SP
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Patch Set 1: Code-Review+1

(1 comment)

Patchset:

PS1:
> since the acpi code seems to be part of the acpi spec

Which is violated by the current implementation for the PCIe bits when called
with the CXL UUID. Haven't found much about it, but Linux seems to always call
with this UUID if it's a CXL root. I couldn't figure out if it would still consider
the PCIe bits then, but they are there and this implementation seems not even
Linux compatible.

And that's on top of the odd design, unnecessary repetition in the generated
code (per root), and unnecessary repetition at runtime for this. IMO, we should
first discuss the generated code, then how it is generated (or if it should be
generated at all?). I'm rather picky about it because new code patterns seem
to have the habit to spread. Upstream, code should be discussed, reviewed and
set a good example, especially in common code areas.

I suggested to move it back because people seemed to be too much in a hurry
for a proper process atm.