[coreboot-gerrit] Change in coreboot[master]: cpu/x86/smm/smm_stub: Add x86_64 support

[Patrick Rudolph (Code Review)]

Hello build bot (Jenkins),

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

https://review.coreboot.org/c/coreboot/+/37392

to look at the new patch set (#3).

Change subject: cpu/x86/smm/smm_stub: Add x86_64 support
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cpu/x86/smm/smm_stub: Add x86_64 support

Enable long mode in SMM handler.
x86_32 isn't affected from this change.

* Enter long mode
* Add 64bit entry to GDT
* Use x86_64 SysV ABI calling conventions for C code entry
* Change smm_module_params' cpu to size_t as 'push' is native integer
* Drop to protected mode after c handler

Tested on Lenovo T410 with additional x86_64 patches.

Change-Id: I26300492e4be62ddd5d80525022c758a019d63a1
Signed-off-by: Patrick Rudolph 
---
M src/cpu/x86/smm/smm_stub.S
M src/include/cpu/x86/smm.h
2 files changed, 49 insertions(+), 4 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/92/37392/3