arch/x86: update assembly to ensure 16-byte alignment into C

When the C compiler expects 16-byte alignment of the stack it is
at the call instruction.  Correct existing call points from assembly
to ensure the stacks are aligned to 16 bytes at the call instruction.

Change-Id: Icadd7a1f9284e92aecd99c30cb2acb307823682c
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: https://review.coreboot.org/20314
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>
This commit is contained in:
Aaron Durbin 2017-06-23 11:14:58 -05:00 committed by Martin Roth
parent d28bd0c79e
commit 028e18ff3c
2 changed files with 20 additions and 1 deletions

View File

@ -27,6 +27,9 @@ post_car_stack_top:
.text
.global _start
_start:
/* Assume stack alignment doesn't matter here as chipset_teardown_car
is expected to be implemented in assembly. */
/* chipset_teardown_car() is expected to disable cache-as-ram. */
call chipset_teardown_car
@ -56,11 +59,20 @@ _start:
*/
#if IS_ENABLED(CONFIG_SOC_SETS_MSRS)
push %esp
mov %esp, %ebp
/* Need to align stack to 16 bytes at the call instruction. Therefore
account for the 1 push. */
andl $0xfffffff0, %esp
sub $12, %esp
push %ebp
call soc_set_mtrrs
/* Ignore fixing up %esp since we're setting it a new value. */
/* eax: new top_of_stack with setup_stack_and_mtrrs data removed */
movl %eax, %esp
/* Align stack to 16 bytes at call instruction. */
andl $0xfffffff0, %esp
call soc_enable_mtrrs
#else /* CONFIG_SOC_SETS_MSRS */
/* Clear variable MTRRs. */
@ -109,6 +121,8 @@ _start:
wrmsr
#endif /* CONFIG_SOC_SETS_MSRS */
/* Align stack to 16 bytes at call instruction. */
andl $0xfffffff0, %esp
/* Call into main for postcar. */
call main
/* Should never return. */

View File

@ -184,6 +184,11 @@ car_init_done:
/* Setup bootblock stack */
mov $_car_stack_end, %esp
/* Need to align stack to 16 bytes at call instruction. Account for
the two pushes below. */
andl $0xfffffff0, %esp
sub $8, %esp
/*push TSC value to stack*/
movd %mm2, %eax
pushl %eax /* tsc[63:32] */