copy_page.S
2.06 KB
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
/*
* Copyright (C) 2012 ARM Ltd.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/linkage.h>
#include <linux/const.h>
#include <asm/assembler.h>
#include <asm/page.h>
#include <asm/cpufeature.h>
#include <asm/alternative.h>
/*
* Copy a page from src to dest (both are page aligned)
*
* Parameters:
* x0 - dest
* x1 - src
*/
ENTRY(copy_page)
alternative_if ARM64_HAS_NO_HW_PREFETCH
// Prefetch three cache lines ahead.
prfm pldl1strm, [x1, #128]
prfm pldl1strm, [x1, #256]
prfm pldl1strm, [x1, #384]
alternative_else_nop_endif
ldp x2, x3, [x1]
ldp x4, x5, [x1, #16]
ldp x6, x7, [x1, #32]
ldp x8, x9, [x1, #48]
ldp x10, x11, [x1, #64]
ldp x12, x13, [x1, #80]
ldp x14, x15, [x1, #96]
ldp x16, x17, [x1, #112]
mov x18, #(PAGE_SIZE - 128)
add x1, x1, #128
1:
subs x18, x18, #128
alternative_if ARM64_HAS_NO_HW_PREFETCH
prfm pldl1strm, [x1, #384]
alternative_else_nop_endif
stnp x2, x3, [x0]
ldp x2, x3, [x1]
stnp x4, x5, [x0, #16]
ldp x4, x5, [x1, #16]
stnp x6, x7, [x0, #32]
ldp x6, x7, [x1, #32]
stnp x8, x9, [x0, #48]
ldp x8, x9, [x1, #48]
stnp x10, x11, [x0, #64]
ldp x10, x11, [x1, #64]
stnp x12, x13, [x0, #80]
ldp x12, x13, [x1, #80]
stnp x14, x15, [x0, #96]
ldp x14, x15, [x1, #96]
stnp x16, x17, [x0, #112]
ldp x16, x17, [x1, #112]
add x0, x0, #128
add x1, x1, #128
b.gt 1b
stnp x2, x3, [x0]
stnp x4, x5, [x0, #16]
stnp x6, x7, [x0, #32]
stnp x8, x9, [x0, #48]
stnp x10, x11, [x0, #64]
stnp x12, x13, [x0, #80]
stnp x14, x15, [x0, #96]
stnp x16, x17, [x0, #112]
ret
ENDPROC(copy_page)