[XS] Change in coreboot[master]: arch/x86: Adjust stack pointer to point to dummy argument

[Sridhar Siricilla (Code Review)]

Sridhar Siricilla has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/76878?usp=email )

Change subject: arch/x86: Adjust stack pointer to point to dummy argument
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arch/x86: Adjust stack pointer to point to dummy argument

The patch pushes dummy argument so that stack pointer points to this
dummy element instead of coreboot table address as depthcharge picks the
second element from top of the stack as coreboot table address.

The change is applicable when system switches from long mode to
protected mode before passing the control to depthcharge.

TEST=Tested in simics environment.64bit coreboot could boot
to OS.

Signed-off-by: Sridhar Siricilla 
Change-Id: I6e4034f65f5db23560f774f56e0edfb08e4283ad
---
M src/arch/x86/c_exit.S
1 file changed, 1 insertion(+), 1 deletion(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/78/76878/1

diff --git a/src/arch/x86/c_exit.S b/src/arch/x86/c_exit.S
index 069a66c..869be3f 100644
--- a/src/arch/x86/c_exit.S
+++ b/src/arch/x86/c_exit.S
@@ -31,6 +31,6 @@
    andl	$0xFFFFFFF0, %esp
    subl	$12, %esp
    pushl	%ebx	/* Argument 0 */
-
+	pushl   $0	/* Dummy argument */
    jmp	*%eax
 #endif