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cpu/x86/reset16.S: Remove handcoded reset vector

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Only 3 bytes should be used for the reset vector and it looks like
modern tooling has no problem with using a regular relative jump
instruction.

TESTED: Qemu Q35 still boots fine.

Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Change-Id: Ie371000c60d66c032a8dcccb98e7627df09d3aa4
Reviewed-on: https://review.coreboot.org/c/coreboot/+/74797
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Elyes Haouas <ehaouas@noos.fr>
Reviewed-by: Matt DeVillier <matt.devillier@gmail.com>
This commit is contained in:
Arthur Heymans 2023-04-26 23:41:11 +02:00 • committed by Matt DeVillier
commit 53810448fc
1 changed files with 1 additions and 8 deletions
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9
src/cpu/x86/reset16.S
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@ -4,11 +4,4 @@
.code16
.globl _start
_start:
.byte 0xe9
.int _start16bit - ( . + 2 )
/* Note: The above jump is hand coded to work around bugs in binutils.
* 5 byte are used for a 3 byte instruction. This works because x86
* is little endian and allows us to use supported 32bit relocations
* instead of the weird 16 bit relocations that binutils does not
* handle consistently between versions because they are used so rarely.
*/
jmp _start16bit