Change in coreboot[master]: [WIP] cpu/x86/lapic: Fix choice X2APIC_ONLY

[Tim Wawrzynczak (Code Review)]

Attention is currently required from: Nico Huber, Wonkyu Kim, Kyösti Mälkki.
Tim Wawrzynczak has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/60213 )

Change subject: [WIP] cpu/x86/lapic: Fix choice X2APIC_ONLY
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Patch Set 2:

(1 comment)

File src/cpu/x86/mp_init.c:

https://review.coreboot.org/c/coreboot/+/60213/comment/588e32a6_7b2456bd 
PS2, Line 652: lapic_send_ipi(LAPIC_INT_ASSERT | LAPIC_DM_SMI, lapicid());
> We can do that. There is also stop_this_cpu(), like mentioned before. […]

Sorry let me be more clear. I mean, if a delay or fence, etc. is required so that no further "real" instructions are executed, maybe we should wrap that whole sequence up into its own function, so we don't need the delay loop/fence/whatever sprinkled around.