[coreboot-gerrit] Change in coreboot[master]: cpu/x86: Define INSTALL_SMM option

[Kyösti Mälkki (Code Review)]

Kyösti Mälkki has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/34257 )

Change subject: cpu/x86: Define INSTALL_SMM option
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Patch Set 1:

Three scenarios to consider:

a) INSTALL_SMM=y, HAVE_SMI_HANDLER=y

Current (unfortunate) situation. Build and install smm -class. Let MP init raise SMIs and do its job.

b) INSTALL_SMM=n, HAVE_SMI_HANDLER=y

Don't build smm -class.
Absolute minimal resident SMM may be installed, like asm inline "rsm"?
Let MP init raise SMIs to relocate SMM stacks?
On entry to payload, SMRAM can be locked or left unlocked.

c) INSTALL_SMM=n, HAVE_SMI_HANDLER=n

Not possible for MP init to raise SMIs.
See CB:34152 and CB:34158 what is required on source level.
Little benefits in comparison to b) above?