xref: /openbmc/linux/arch/x86/lib/msr-reg.S (revision b96fc2f3)
1#include <linux/linkage.h>
2#include <linux/errno.h>
3#include <asm/asm.h>
4#include <asm/msr.h>
5
6#ifdef CONFIG_X86_64
7/*
8 * int {rdmsr,wrmsr}_safe_regs(u32 gprs[8]);
9 *
10 * reg layout: u32 gprs[eax, ecx, edx, ebx, esp, ebp, esi, edi]
11 *
12 */
13.macro op_safe_regs op
14ENTRY(\op\()_safe_regs)
15	pushq %rbx
16	pushq %rbp
17	movq	%rdi, %r10	/* Save pointer */
18	xorl	%r11d, %r11d	/* Return value */
19	movl    (%rdi), %eax
20	movl    4(%rdi), %ecx
21	movl    8(%rdi), %edx
22	movl    12(%rdi), %ebx
23	movl    20(%rdi), %ebp
24	movl    24(%rdi), %esi
25	movl    28(%rdi), %edi
261:	\op
272:	movl    %eax, (%r10)
28	movl	%r11d, %eax	/* Return value */
29	movl    %ecx, 4(%r10)
30	movl    %edx, 8(%r10)
31	movl    %ebx, 12(%r10)
32	movl    %ebp, 20(%r10)
33	movl    %esi, 24(%r10)
34	movl    %edi, 28(%r10)
35	popq %rbp
36	popq %rbx
37	ret
383:
39	movl    $-EIO, %r11d
40	jmp     2b
41
42	_ASM_EXTABLE(1b, 3b)
43ENDPROC(\op\()_safe_regs)
44.endm
45
46#else /* X86_32 */
47
48.macro op_safe_regs op
49ENTRY(\op\()_safe_regs)
50	pushl %ebx
51	pushl %ebp
52	pushl %esi
53	pushl %edi
54	pushl $0              /* Return value */
55	pushl %eax
56	movl    4(%eax), %ecx
57	movl    8(%eax), %edx
58	movl    12(%eax), %ebx
59	movl    20(%eax), %ebp
60	movl    24(%eax), %esi
61	movl    28(%eax), %edi
62	movl    (%eax), %eax
631:	\op
642:	pushl %eax
65	movl    4(%esp), %eax
66	popl (%eax)
67	addl    $4, %esp
68	movl    %ecx, 4(%eax)
69	movl    %edx, 8(%eax)
70	movl    %ebx, 12(%eax)
71	movl    %ebp, 20(%eax)
72	movl    %esi, 24(%eax)
73	movl    %edi, 28(%eax)
74	popl %eax
75	popl %edi
76	popl %esi
77	popl %ebp
78	popl %ebx
79	ret
803:
81	movl    $-EIO, 4(%esp)
82	jmp     2b
83
84	_ASM_EXTABLE(1b, 3b)
85ENDPROC(\op\()_safe_regs)
86.endm
87
88#endif
89
90op_safe_regs rdmsr
91op_safe_regs wrmsr
92
93