[coreboot-gerrit] Change in coreboot[master]: *x86: Support x2apic mode

[Wonkyu Kim (Code Review)]

Attention is currently required from: Furquan Shaikh, Jamie Ryu, Paul Menzel, Subrata Banik, Raj Astekar, Patrick Rudolph.
Wonkyu Kim has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/51723 )

Change subject: *x86: Support x2apic mode
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Patch Set 6:

(4 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/51723/comment/3a0b4766_fdc9916d 
PS5, Line 7: src/*/x86 :
> Please remove the space before the colon. […]

Done

https://review.coreboot.org/c/coreboot/+/51723/comment/ca7efc1d_3bdbc003 
PS5, Line 9: Implement x2apic mode as existing code only supports apic mode
> Please add dot/period to the end of sentences. […]

Done

https://review.coreboot.org/c/coreboot/+/51723/comment/205d6d67_c3d3e562 
PS5, Line 14: cat /proc/cpuinfo | grep "apicid"
> On what board? […]

example log is attached.  Board is new platform which is not upstreammed yet.  Will be upstreammed once we get legal approval.

File src/cpu/x86/lapic/lapic.c:

https://review.coreboot.org/c/coreboot/+/51723/comment/cbe7e526_4de3b3cc 
PS5, Line 50: 	printk(BIOS_DEBUG, " apic_id: 0x%x ", lapicid());
> Why does this need to be changed?

x2apic is 16bit while apic is 8bit