xref: /openbmc/u-boot/arch/x86/cpu/i386/setjmp.S (revision dd1033e4)
1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Written by H. Peter Anvin <hpa@zytor.com>
4 * Brought in from Linux v4.4 and modified for U-Boot
5 * From Linux arch/um/sys-i386/setjmp.S
6 */
7
8#define _REGPARM
9
10/*
11 * The jmp_buf is assumed to contain the following, in order:
12 *	%ebx
13 *	%esp
14 *	%ebp
15 *	%esi
16 *	%edi
17 *	<return address>
18 */
19
20	.text
21	.align 4
22	.globl setjmp
23	.type setjmp, @function
24setjmp:
25#ifdef _REGPARM
26	movl %eax, %edx
27#else
28	movl 4(%esp), %edx
29#endif
30	popl %ecx		/* Return address, and adjust the stack */
31	xorl %eax, %eax		/* Return value */
32	movl %ebx, (%edx)
33	movl %esp, 4(%edx)	/* Post-return %esp! */
34	pushl %ecx		/* Make the call/return stack happy */
35	movl %ebp, 8(%edx)
36	movl %esi, 12(%edx)
37	movl %edi, 16(%edx)
38	movl %ecx, 20(%edx)	/* Return address */
39	ret
40
41	/* Provide function size if needed */
42	.size setjmp, .-setjmp
43
44	.align 4
45	.globl longjmp
46	.type longjmp, @function
47longjmp:
48#ifdef _REGPARM
49	xchgl %eax, %edx
50#else
51	movl 4(%esp), %edx	/* jmp_ptr address */
52#endif
53	movl (%edx), %ebx
54	movl 4(%edx), %esp
55	movl 8(%edx), %ebp
56	movl 12(%edx), %esi
57	movl 16(%edx), %edi
58	jmp *20(%edx)
59
60	.size longjmp, .-longjmp
61