[coreboot-gerrit] Change in coreboot[master]: arch/x86: Attempt to boot without postcar stage/phase

[Arthur Heymans (Code Review)]

Arthur Heymans has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/34752 )

Change subject: arch/x86: Attempt to boot without postcar stage/phase
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Patch Set 3:

(2 comments)

https://review.coreboot.org/c/coreboot/+/34752/2/src/arch/x86/c_start.S 
File src/arch/x86/c_start.S:

https://review.coreboot.org/c/coreboot/+/34752/2/src/arch/x86/c_start.S@42 
PS2, Line 42: _start:
> incase we would like to tear down car in ranmstage then ramstage entry point will b exit_car. […]

Sorry, I meant a weak symbol that calls the code in exit_car.S where you split off the _start in exit_car.S to a different stub file.

https://review.coreboot.org/c/coreboot/+/34752/2/src/arch/x86/exit_car.S 
File src/arch/x86/exit_car.S:

https://review.coreboot.org/c/coreboot/+/34752/2/src/arch/x86/exit_car.S@48 
PS2, Line 48: post_car_stack_top
> no, it will be only once, either by postcar or by ramstage based on if postcar is present or not. […]

The stackpointer is moved here and at L76 in c_start.S "movl	$_estack, %esp". If I recall correctly sometimes C code is called to tear down car...