summaryrefslogtreecommitdiffstats
path: root/arch/x86/lib/msr-reg.S
blob: ed33cbab39582f0c057a301a2e63882c6cd260c1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
/* SPDX-License-Identifier: GPL-2.0 */
#include <linux/linkage.h>
#include <linux/errno.h>
#include <asm/asm.h>
#include <asm/msr.h>

#ifdef CONFIG_X86_64
/*
 * int {rdmsr,wrmsr}_safe_regs(u32 gprs[8]);
 *
 * reg layout: u32 gprs[eax, ecx, edx, ebx, esp, ebp, esi, edi]
 *
 */
.macro op_safe_regs op
ENTRY(\op\()_safe_regs)
	pushq %rbx
	pushq %r12
	movq	%rdi, %r10	/* Save pointer */
	xorl	%r11d, %r11d	/* Return value */
	movl    (%rdi), %eax
	movl    4(%rdi), %ecx
	movl    8(%rdi), %edx
	movl    12(%rdi), %ebx
	movl    20(%rdi), %r12d
	movl    24(%rdi), %esi
	movl    28(%rdi), %edi
1:	\op
2:	movl    %eax, (%r10)
	movl	%r11d, %eax	/* Return value */
	movl    %ecx, 4(%r10)
	movl    %edx, 8(%r10)
	movl    %ebx, 12(%r10)
	movl    %r12d, 20(%r10)
	movl    %esi, 24(%r10)
	movl    %edi, 28(%r10)
	popq %r12
	popq %rbx
	ret
3:
	movl    $-EIO, %r11d
	jmp     2b

	_ASM_EXTABLE(1b, 3b)
ENDPROC(\op\()_safe_regs)
.endm

#else /* X86_32 */

.macro op_safe_regs op
ENTRY(\op\()_safe_regs)
	pushl %ebx
	pushl %ebp
	pushl %esi
	pushl %edi
	pushl $0              /* Return value */
	pushl %eax
	movl    4(%eax), %ecx
	movl    8(%eax), %edx
	movl    12(%eax), %ebx
	movl    20(%eax), %ebp
	movl    24(%eax), %esi
	movl    28(%eax), %edi
	movl    (%eax), %eax
1:	\op
2:	pushl %eax
	movl    4(%esp), %eax
	popl (%eax)
	addl    $4, %esp
	movl    %ecx, 4(%eax)
	movl    %edx, 8(%eax)
	movl    %ebx, 12(%eax)
	movl    %ebp, 20(%eax)
	movl    %esi, 24(%eax)
	movl    %edi, 28(%eax)
	popl %eax
	popl %edi
	popl %esi
	popl %ebp
	popl %ebx
	ret
3:
	movl    $-EIO, 4(%esp)
	jmp     2b

	_ASM_EXTABLE(1b, 3b)
ENDPROC(\op\()_safe_regs)
.endm

#endif

op_safe_regs rdmsr
op_safe_regs wrmsr

OpenPOWER on IntegriCloud