Aaron Durbin has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/46834 )
Change subject: x86: Put bootblock startup code into .text._start section ......................................................................
Patch Set 1: Code-Review+2
(3 comments)
I don't think anything is exceeding CONFIG_C_ENV_BOOTBLOCK_SIZE of 64KiB:
$ git grep -A 2 C_ENV_BOOTBLOCK_SIZE | grep default | sed -e 's/if .*//' | awk '{ print $NF}' | sort | uniq -c 2 0x10000 7 0x4000 7 0x8000 10 0xC000
So I think we should be good.
https://review.coreboot.org/c/coreboot/+/46834/1//COMMIT_MSG Commit Message:
https://review.coreboot.org/c/coreboot/+/46834/1//COMMIT_MSG@12 PS1, Line 12: bit but
https://review.coreboot.org/c/coreboot/+/46834/1//COMMIT_MSG@14 PS1, Line 14: _start16bit It needs to be within 64KiB of reset vector which is the end of the bootblock program for dealing with a 16-bit jump instructions.
https://review.coreboot.org/c/coreboot/+/46834/1//COMMIT_MSG@16 PS1, Line 16: lot of space if it didn't.) The 4KiB alignment requirement is only for certain platforms where the APs need to be SIPI'd towards the same flow as BSP. It doesn't need to be there all the time. You can see a symbol being made, ap_sipi_vector_in_rom, in src/cpu/x86/16bit/entry16.ld. From the looks of it, only src/cpu/intel/car/p4-netburst/cache_as_ram.S has a reference to that symbol.