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cpu/x86/cpu_info.S: Remove ebx save/restore

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The push/pop of %ebx was only added because smm_stub saves the canary
value in it. Now that we no longer use cpu_info in smm, we no longer
need to save the register.

BUG=b:179699789
TEST=Boot guybrush to the OS

Signed-off-by: Raul E Rangel <rrangel@chromium.org>
Change-Id: I554dbe016db8b1c61246c8ffc7fa252b2542ba92
Reviewed-on: https://review.coreboot.org/c/coreboot/+/58205
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Karthik Ramasubramanian <kramasub@google.com>
This commit is contained in:
Raul E Rangel
2021-10-08 13:10:38 -06:00
committed by Felix Held
parent db3e4b943a
commit 9ae922abf7
1 changed files with 1 additions and 3 deletions
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4
src/cpu/x86/cpu_info.S.inc
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@@ -28,12 +28,11 @@
* @desc_index: Index of the descriptor in the table. Defaults to 0. Must be a * @desc_index: Index of the descriptor in the table. Defaults to 0. Must be a
* register if specified. * register if specified.
* *
* Clobbers %eax. * Clobbers %eax, %ebx.
*/ */
.macro set_segment_descriptor_base desc_array:req, base:req, desc_index .macro set_segment_descriptor_base desc_array:req, base:req, desc_index
mov \base, %eax mov \base, %eax
push %ebx /* preserve ebx */
mov \desc_array, %ebx mov \desc_array, %ebx
.ifb \desc_index .ifb \desc_index
@@ -50,5 +49,4 @@
movb %al, 7(%ebx, \desc_index, 8) movb %al, 7(%ebx, \desc_index, 8)
.endif .endif
pop %ebx
.endm .endm