blob: feec3d3628032f433dbf65e006b8a07acfbc161c [file] [log] [blame]
/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 2020-2022 Loongson Technology Corporation Limited
*/
#include <linux/export.h>
#include <asm/alternative-asm.h>
#include <asm/asm.h>
#include <asm/asmmacro.h>
#include <asm/asm-extable.h>
#include <asm/cpu.h>
#include <asm/regdef.h>
SYM_FUNC_START(__copy_user)
/*
* Some CPUs support hardware unaligned access
*/
ALTERNATIVE "b __copy_user_generic", \
"b __copy_user_fast", CPU_FEATURE_UAL
SYM_FUNC_END(__copy_user)
EXPORT_SYMBOL(__copy_user)
/*
* unsigned long __copy_user_generic(void *to, const void *from, size_t n)
*
* a0: to
* a1: from
* a2: n
*/
SYM_FUNC_START(__copy_user_generic)
beqz a2, 3f
1: ld.b t0, a1, 0
2: st.b t0, a0, 0
addi.d a0, a0, 1
addi.d a1, a1, 1
addi.d a2, a2, -1
bgtz a2, 1b
3: move a0, a2
jr ra
_asm_extable 1b, 3b
_asm_extable 2b, 3b
SYM_FUNC_END(__copy_user_generic)
/*
* unsigned long __copy_user_fast(void *to, const void *from, unsigned long n)
*
* a0: to
* a1: from
* a2: n
*/
SYM_FUNC_START(__copy_user_fast)
sltui t0, a2, 9
bnez t0, .Lsmall
0: ld.d t0, a1, 0
1: st.d t0, a0, 0
add.d a3, a1, a2
add.d a2, a0, a2
/* align up destination address */
andi t1, a0, 7
sub.d t0, zero, t1
addi.d t0, t0, 8
add.d a1, a1, t0
add.d a0, a0, t0
addi.d a4, a3, -64
bgeu a1, a4, .Llt64
/* copy 64 bytes at a time */
.Lloop64:
2: ld.d t0, a1, 0
3: ld.d t1, a1, 8
4: ld.d t2, a1, 16
5: ld.d t3, a1, 24
6: ld.d t4, a1, 32
7: ld.d t5, a1, 40
8: ld.d t6, a1, 48
9: ld.d t7, a1, 56
10: st.d t0, a0, 0
11: st.d t1, a0, 8
12: st.d t2, a0, 16
13: st.d t3, a0, 24
14: st.d t4, a0, 32
15: st.d t5, a0, 40
16: st.d t6, a0, 48
17: st.d t7, a0, 56
addi.d a1, a1, 64
addi.d a0, a0, 64
bltu a1, a4, .Lloop64
/* copy the remaining bytes */
.Llt64:
addi.d a4, a3, -32
bgeu a1, a4, .Llt32
18: ld.d t0, a1, 0
19: ld.d t1, a1, 8
20: ld.d t2, a1, 16
21: ld.d t3, a1, 24
22: st.d t0, a0, 0
23: st.d t1, a0, 8
24: st.d t2, a0, 16
25: st.d t3, a0, 24
addi.d a1, a1, 32
addi.d a0, a0, 32
.Llt32:
addi.d a4, a3, -16
bgeu a1, a4, .Llt16
26: ld.d t0, a1, 0
27: ld.d t1, a1, 8
28: st.d t0, a0, 0
29: st.d t1, a0, 8
addi.d a1, a1, 16
addi.d a0, a0, 16
.Llt16:
addi.d a4, a3, -8
bgeu a1, a4, .Llt8
30: ld.d t0, a1, 0
31: st.d t0, a0, 0
addi.d a1, a1, 8
addi.d a0, a0, 8
.Llt8:
32: ld.d t0, a3, -8
33: st.d t0, a2, -8
/* return */
move a0, zero
jr ra
.align 5
.Lsmall:
pcaddi t0, 8
slli.d a3, a2, 5
add.d t0, t0, a3
jr t0
.align 5
move a0, zero
jr ra
.align 5
34: ld.b t0, a1, 0
35: st.b t0, a0, 0
move a0, zero
jr ra
.align 5
36: ld.h t0, a1, 0
37: st.h t0, a0, 0
move a0, zero
jr ra
.align 5
38: ld.h t0, a1, 0
39: ld.b t1, a1, 2
40: st.h t0, a0, 0
41: st.b t1, a0, 2
move a0, zero
jr ra
.align 5
42: ld.w t0, a1, 0
43: st.w t0, a0, 0
move a0, zero
jr ra
.align 5
44: ld.w t0, a1, 0
45: ld.b t1, a1, 4
46: st.w t0, a0, 0
47: st.b t1, a0, 4
move a0, zero
jr ra
.align 5
48: ld.w t0, a1, 0
49: ld.h t1, a1, 4
50: st.w t0, a0, 0
51: st.h t1, a0, 4
move a0, zero
jr ra
.align 5
52: ld.w t0, a1, 0
53: ld.w t1, a1, 3
54: st.w t0, a0, 0
55: st.w t1, a0, 3
move a0, zero
jr ra
.align 5
56: ld.d t0, a1, 0
57: st.d t0, a0, 0
move a0, zero
jr ra
/* fixup and ex_table */
.Llarge_fixup:
sub.d a2, a2, a0
.Lsmall_fixup:
58: ld.b t0, a1, 0
59: st.b t0, a0, 0
addi.d a0, a0, 1
addi.d a1, a1, 1
addi.d a2, a2, -1
bgt a2, zero, 58b
.Lexit:
move a0, a2
jr ra
_asm_extable 0b, .Lsmall_fixup
_asm_extable 1b, .Lsmall_fixup
_asm_extable 2b, .Llarge_fixup
_asm_extable 3b, .Llarge_fixup
_asm_extable 4b, .Llarge_fixup
_asm_extable 5b, .Llarge_fixup
_asm_extable 6b, .Llarge_fixup
_asm_extable 7b, .Llarge_fixup
_asm_extable 8b, .Llarge_fixup
_asm_extable 9b, .Llarge_fixup
_asm_extable 10b, .Llarge_fixup
_asm_extable 11b, .Llarge_fixup
_asm_extable 12b, .Llarge_fixup
_asm_extable 13b, .Llarge_fixup
_asm_extable 14b, .Llarge_fixup
_asm_extable 15b, .Llarge_fixup
_asm_extable 16b, .Llarge_fixup
_asm_extable 17b, .Llarge_fixup
_asm_extable 18b, .Llarge_fixup
_asm_extable 19b, .Llarge_fixup
_asm_extable 20b, .Llarge_fixup
_asm_extable 21b, .Llarge_fixup
_asm_extable 22b, .Llarge_fixup
_asm_extable 23b, .Llarge_fixup
_asm_extable 24b, .Llarge_fixup
_asm_extable 25b, .Llarge_fixup
_asm_extable 26b, .Llarge_fixup
_asm_extable 27b, .Llarge_fixup
_asm_extable 28b, .Llarge_fixup
_asm_extable 29b, .Llarge_fixup
_asm_extable 30b, .Llarge_fixup
_asm_extable 31b, .Llarge_fixup
_asm_extable 32b, .Llarge_fixup
_asm_extable 33b, .Llarge_fixup
_asm_extable 34b, .Lexit
_asm_extable 35b, .Lexit
_asm_extable 36b, .Lsmall_fixup
_asm_extable 37b, .Lsmall_fixup
_asm_extable 38b, .Lsmall_fixup
_asm_extable 39b, .Lsmall_fixup
_asm_extable 40b, .Lsmall_fixup
_asm_extable 41b, .Lsmall_fixup
_asm_extable 42b, .Lsmall_fixup
_asm_extable 43b, .Lsmall_fixup
_asm_extable 44b, .Lsmall_fixup
_asm_extable 45b, .Lsmall_fixup
_asm_extable 46b, .Lsmall_fixup
_asm_extable 47b, .Lsmall_fixup
_asm_extable 48b, .Lsmall_fixup
_asm_extable 49b, .Lsmall_fixup
_asm_extable 50b, .Lsmall_fixup
_asm_extable 51b, .Lsmall_fixup
_asm_extable 52b, .Lsmall_fixup
_asm_extable 53b, .Lsmall_fixup
_asm_extable 54b, .Lsmall_fixup
_asm_extable 55b, .Lsmall_fixup
_asm_extable 56b, .Lsmall_fixup
_asm_extable 57b, .Lsmall_fixup
_asm_extable 58b, .Lexit
_asm_extable 59b, .Lexit
SYM_FUNC_END(__copy_user_fast)