xref: /openbmc/u-boot/arch/x86/cpu/i386/setjmp.S (revision 274bced8)
1/*
2 * Written by H. Peter Anvin <hpa@zytor.com>
3 * Brought in from Linux v4.4 and modified for U-Boot
4 * From Linux arch/um/sys-i386/setjmp.S
5 *
6 * SPDX-License-Identifier:	GPL-2.0
7 */
8
9#define _REGPARM
10
11/*
12 * The jmp_buf is assumed to contain the following, in order:
13 *	%ebx
14 *	%esp
15 *	%ebp
16 *	%esi
17 *	%edi
18 *	<return address>
19 */
20
21	.text
22	.align 4
23	.globl setjmp
24	.type setjmp, @function
25setjmp:
26#ifdef _REGPARM
27	movl %eax, %edx
28#else
29	movl 4(%esp), %edx
30#endif
31	popl %ecx		/* Return address, and adjust the stack */
32	xorl %eax, %eax		/* Return value */
33	movl %ebx, (%edx)
34	movl %esp, 4(%edx)	/* Post-return %esp! */
35	pushl %ecx		/* Make the call/return stack happy */
36	movl %ebp, 8(%edx)
37	movl %esi, 12(%edx)
38	movl %edi, 16(%edx)
39	movl %ecx, 20(%edx)	/* Return address */
40	ret
41
42	/* Provide function size if needed */
43	.size setjmp, .-setjmp
44
45	.align 4
46	.globl longjmp
47	.type longjmp, @function
48longjmp:
49#ifdef _REGPARM
50	xchgl %eax, %edx
51#else
52	movl 4(%esp), %edx	/* jmp_ptr address */
53#endif
54	movl (%edx), %ebx
55	movl 4(%edx), %esp
56	movl 8(%edx), %ebp
57	movl 12(%edx), %esi
58	movl 16(%edx), %edi
59	jmp *20(%edx)
60
61	.size longjmp, .-longjmp
62