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

[Wonkyu Kim (Code Review)]

Attention is currently required from: Furquan Shaikh, Jamie Ryu, Wonkyu Kim, Paul Menzel, Angel Pons, Subrata Banik, Kyösti Mälkki, Raj Astekar, Aaron Durbin, Patrick Rudolph.
Hello build bot (Jenkins), Furquan Shaikh, Patrick Georgi, Ravishankar Sarawadi, Paul Menzel, Subrata Banik, Kyösti Mälkki, Aaron Durbin, Patrick Rudolph, Lance Zhao, Nico Huber, Jamie Ryu, Srinidhi N Kaushik, Raj Astekar,

I'd like you to reexamine a change. Please visit

https://review.coreboot.org/c/coreboot/+/51723

to look at the new patch set (#7).

Change subject: *x86: Support x2apic mode
......................................................................

*x86: Support x2apic mode

Implement x2apic mode as existing code only supports apic mode.
Use info from LAPIC_BASE_MSR (LAPIC_BASE_MSR_X2APIC_MODE) to check
if apic mode or x2apic mode and implement x2apic mode according to
x2apic specfication.

Reference:
https://software.intel.com/content/www/us/en/develop/download/
intel-64-architecture-x2apic-specification.html

BUG=None
BRANCH=None
TEST=boot to OS and check apic mode
cat /proc/cpuinfo | grep "apicid"
ex) can see apicid bigger than 255
apicid          : 256
apicid          : 260

Signed-off-by: Wonkyu Kim 
Change-Id: I0bb729b0521fb9dc38b7981014755daeaf9ca817
---
M src/arch/x86/cpu.c
M src/cpu/x86/lapic/lapic.c
M src/cpu/x86/lapic/lapic_cpu_init.c
M src/cpu/x86/mp_init.c
M src/cpu/x86/smm/smm_stub.S
M src/include/cpu/x86/lapic.h
M src/include/cpu/x86/lapic_def.h
M src/include/cpu/x86/smm.h
8 files changed, 227 insertions(+), 116 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/23/51723/7