[coreboot-gerrit] Change in coreboot[master]: src/cpu: Add EXPERIMENTAL_X86_64 option

[Felix Held (Code Review)]

Attention is currently required from: Jason Glenesk, Raul Rangel, Marshall Dawson, Mariusz Szafrański, Suresh Bellampalli, Vanessa Eusebio, Michal Motyl, Andrey Petrov, Patrick Rudolph, HAOUAS Elyes.
Felix Held has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/49506 )

Change subject: src/cpu: Add EXPERIMENTAL_X86_64 option
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Patch Set 17:

(3 comments)

Patchset:

PS17: 
hm, this is useful to see what breaks in a 64 bit build (quite a bit and often in unexpected places), but it addds quite a bit of clutter, so i'm not really sure if i'd like this approach to be merged

File src/soc/amd/cezanne/Kconfig:

https://review.coreboot.org/c/coreboot/+/49506/comment/75b663c4_ff8e8c11 
PS14, Line 13: 	select ARCH_ALL_STAGES_X86_32 if !ARCH_EXP_X86_64
like in picasso verstage can either be arm or x86, all stages is wrong here

File src/soc/amd/stoneyridge/Kconfig:

https://review.coreboot.org/c/coreboot/+/49506/comment/96c76a56_5c0ae080 
PS14, Line 16: 	select ARCH_ALL_STAGES_X86_64 if ARCH_EXP_X86_64
haven't looked into the details, but x86_64 will probably break the binaryPI integration without switching back to 32 bit mode before calling into the binary like the fsp 2 driver does