Change in coreboot[master]: payloads/external/tianocore: Add build argument for 4G Decode

[Sean Rhodes (Code Review)]

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Sean Rhodes has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/56223 )

Change subject: payloads/external/tianocore: Add build argument for 4G Decode
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Patch Set 8:

(1 comment)

This change is ready for review.

File payloads/external/tianocore/Kconfig:

https://review.coreboot.org/c/coreboot/+/56223/comment/3777cbea_67a55609 
PS7, Line 99: 	  for Qubes (Xen).
> > "Above 4G Decoding" follows the term used by other firmware platforms; might make it easier for ot […]

Mapping would probably be a better way of putting it, but descriptions aren't my strong suit!

It's basically reserving memory so that EFI_RESOURCE_ATTRIBUTE_TESTED isn't set on any memory above 4GB in the resource HOB.

If it helps (still WIP as the build argument is proving as co-operative as a brick):
https://github.com/StarLabsLtd/edk2/commit/93085320b732e19a4f569235955fcc006...