aboutsummaryrefslogtreecommitdiffstats
path: root/arch/x86/boot/copy.S
blob: 11f272c6f5e9e0c2fcf11b030ee6d6df3cf2dd64 (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
/* ----------------------------------------------------------------------- *
 *
 *   Copyright (C) 1991, 1992 Linus Torvalds
 *   Copyright 2007 rPath, Inc. - All Rights Reserved
 *
 *   This file is part of the Linux kernel, and is made available under
 *   the terms of the GNU General Public License version 2.
 *
 * ----------------------------------------------------------------------- */

#include <linux/linkage.h>

/*
 * Memory copy routines
 */

	.code16gcc
	.text

GLOBAL(memcpy)
	pushw	%si
	pushw	%di
	movw	%ax, %di
	movw	%dx, %si
	pushw	%cx
	shrw	$2, %cx
	rep; movsl
	popw	%cx
	andw	$3, %cx
	rep; movsb
	popw	%di
	popw	%si
	ret
ENDPROC(memcpy)

GLOBAL(memset)
	pushw	%di
	movw	%ax, %di
	movzbl	%dl, %eax
	imull	$0x01010101,%eax
	pushw	%cx
	shrw	$2, %cx
	rep; stosl
	popw	%cx
	andw	$3, %cx
	rep; stosb
	popw	%di
	ret
ENDPROC(memset)

GLOBAL(copy_from_fs)
	pushw	%ds
	pushw	%fs
	popw	%ds
	call	memcpy
	popw	%ds
	ret
ENDPROC(copy_from_fs)

GLOBAL(copy_to_fs)
	pushw	%es
	pushw	%fs
	popw	%es
	call	memcpy
	popw	%es
	ret
ENDPROC(copy_to_fs)

#if 0 /* Not currently used, but can be enabled as needed */
GLOBAL(copy_from_gs)
	pushw	%ds
	pushw	%gs
	popw	%ds
	call	memcpy
	popw	%ds
	ret
ENDPROC(copy_from_gs)

GLOBAL(copy_to_gs)
	pushw	%es
	pushw	%gs
	popw	%es
	call	memcpy
	popw	%es
	ret
ENDPROC(copy_to_gs)
#endif