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1/*
2 * linux/arch/arm/lib/memset.S
3 *
4 * Copyright (C) 1995-2000 Russell King
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 * ASM optimised string functions
11 */
12#include <linux/linkage.h>
13#include <asm/assembler.h>
14#include <asm/unwind.h>
15
16 .text
17 .align 5
18
19ENTRY(mmioset)
20ENTRY(memset)
21UNWIND( .fnstart )
22 ands r3, r0, #3 @ 1 unaligned?
23 mov ip, r0 @ preserve r0 as return value
24 bne 6f @ 1
25/*
26 * we know that the pointer in ip is aligned to a word boundary.
27 */
281: orr r1, r1, r1, lsl #8
29 orr r1, r1, r1, lsl #16
30 mov r3, r1
31 cmp r2, #16
32 blt 4f
33
34#if ! CALGN(1)+0
35
36/*
37 * We need 2 extra registers for this loop - use r8 and the LR
38 */
39 stmfd sp!, {r8, lr}
40UNWIND( .fnend )
41UNWIND( .fnstart )
42UNWIND( .save {r8, lr} )
43 mov r8, r1
44 mov lr, r1
45
462: subs r2, r2, #64
47 stmgeia ip!, {r1, r3, r8, lr} @ 64 bytes at a time.
48 stmgeia ip!, {r1, r3, r8, lr}
49 stmgeia ip!, {r1, r3, r8, lr}
50 stmgeia ip!, {r1, r3, r8, lr}
51 bgt 2b
52 ldmeqfd sp!, {r8, pc} @ Now <64 bytes to go.
53/*
54 * No need to correct the count; we're only testing bits from now on
55 */
56 tst r2, #32
57 stmneia ip!, {r1, r3, r8, lr}
58 stmneia ip!, {r1, r3, r8, lr}
59 tst r2, #16
60 stmneia ip!, {r1, r3, r8, lr}
61 ldmfd sp!, {r8, lr}
62UNWIND( .fnend )
63
64#else
65
66/*
67 * This version aligns the destination pointer in order to write
68 * whole cache lines at once.
69 */
70
71 stmfd sp!, {r4-r8, lr}
72UNWIND( .fnend )
73UNWIND( .fnstart )
74UNWIND( .save {r4-r8, lr} )
75 mov r4, r1
76 mov r5, r1
77 mov r6, r1
78 mov r7, r1
79 mov r8, r1
80 mov lr, r1
81
82 cmp r2, #96
83 tstgt ip, #31
84 ble 3f
85
86 and r8, ip, #31
87 rsb r8, r8, #32
88 sub r2, r2, r8
89 movs r8, r8, lsl #(32 - 4)
90 stmcsia ip!, {r4, r5, r6, r7}
91 stmmiia ip!, {r4, r5}
92 tst r8, #(1 << 30)
93 mov r8, r1
94 strne r1, [ip], #4
95
963: subs r2, r2, #64
97 stmgeia ip!, {r1, r3-r8, lr}
98 stmgeia ip!, {r1, r3-r8, lr}
99 bgt 3b
100 ldmeqfd sp!, {r4-r8, pc}
101
102 tst r2, #32
103 stmneia ip!, {r1, r3-r8, lr}
104 tst r2, #16
105 stmneia ip!, {r4-r7}
106 ldmfd sp!, {r4-r8, lr}
107UNWIND( .fnend )
108
109#endif
110
111UNWIND( .fnstart )
1124: tst r2, #8
113 stmneia ip!, {r1, r3}
114 tst r2, #4
115 strne r1, [ip], #4
116/*
117 * When we get here, we've got less than 4 bytes to zero. We
118 * may have an unaligned pointer as well.
119 */
1205: tst r2, #2
121 strneb r1, [ip], #1
122 strneb r1, [ip], #1
123 tst r2, #1
124 strneb r1, [ip], #1
125 ret lr
126
1276: subs r2, r2, #4 @ 1 do we have enough
128 blt 5b @ 1 bytes to align with?
129 cmp r3, #2 @ 1
130 strltb r1, [ip], #1 @ 1
131 strleb r1, [ip], #1 @ 1
132 strb r1, [ip], #1 @ 1
133 add r2, r2, r3 @ 1 (r2 = r2 - (4 - r3))
134 b 1b
135UNWIND( .fnend )
136ENDPROC(memset)
137ENDPROC(mmioset)
1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * linux/arch/arm/lib/memset.S
4 *
5 * Copyright (C) 1995-2000 Russell King
6 *
7 * ASM optimised string functions
8 */
9#include <linux/linkage.h>
10#include <asm/assembler.h>
11#include <asm/unwind.h>
12
13 .text
14 .align 5
15
16ENTRY(__memset)
17ENTRY(mmioset)
18WEAK(memset)
19UNWIND( .fnstart )
20 and r1, r1, #255 @ cast to unsigned char
21 ands r3, r0, #3 @ 1 unaligned?
22 mov ip, r0 @ preserve r0 as return value
23 bne 6f @ 1
24/*
25 * we know that the pointer in ip is aligned to a word boundary.
26 */
271: orr r1, r1, r1, lsl #8
28 orr r1, r1, r1, lsl #16
29 mov r3, r1
307: cmp r2, #16
31 blt 4f
32UNWIND( .fnend )
33
34#if ! CALGN(1)+0
35
36/*
37 * We need 2 extra registers for this loop - use r8 and the LR
38 */
39UNWIND( .fnstart )
40UNWIND( .save {r8, lr} )
41 stmfd sp!, {r8, lr}
42 mov r8, r1
43 mov lr, r3
44
452: subs r2, r2, #64
46 stmiage ip!, {r1, r3, r8, lr} @ 64 bytes at a time.
47 stmiage ip!, {r1, r3, r8, lr}
48 stmiage ip!, {r1, r3, r8, lr}
49 stmiage ip!, {r1, r3, r8, lr}
50 bgt 2b
51 ldmfdeq sp!, {r8, pc} @ Now <64 bytes to go.
52/*
53 * No need to correct the count; we're only testing bits from now on
54 */
55 tst r2, #32
56 stmiane ip!, {r1, r3, r8, lr}
57 stmiane ip!, {r1, r3, r8, lr}
58 tst r2, #16
59 stmiane ip!, {r1, r3, r8, lr}
60 ldmfd sp!, {r8, lr}
61UNWIND( .fnend )
62
63#else
64
65/*
66 * This version aligns the destination pointer in order to write
67 * whole cache lines at once.
68 */
69
70UNWIND( .fnstart )
71UNWIND( .save {r4-r8, lr} )
72 stmfd sp!, {r4-r8, lr}
73 mov r4, r1
74 mov r5, r3
75 mov r6, r1
76 mov r7, r3
77 mov r8, r1
78 mov lr, r3
79
80 cmp r2, #96
81 tstgt ip, #31
82 ble 3f
83
84 and r8, ip, #31
85 rsb r8, r8, #32
86 sub r2, r2, r8
87 movs r8, r8, lsl #(32 - 4)
88 stmiacs ip!, {r4, r5, r6, r7}
89 stmiami ip!, {r4, r5}
90 tst r8, #(1 << 30)
91 mov r8, r1
92 strne r1, [ip], #4
93
943: subs r2, r2, #64
95 stmiage ip!, {r1, r3-r8, lr}
96 stmiage ip!, {r1, r3-r8, lr}
97 bgt 3b
98 ldmfdeq sp!, {r4-r8, pc}
99
100 tst r2, #32
101 stmiane ip!, {r1, r3-r8, lr}
102 tst r2, #16
103 stmiane ip!, {r4-r7}
104 ldmfd sp!, {r4-r8, lr}
105UNWIND( .fnend )
106
107#endif
108
109UNWIND( .fnstart )
1104: tst r2, #8
111 stmiane ip!, {r1, r3}
112 tst r2, #4
113 strne r1, [ip], #4
114/*
115 * When we get here, we've got less than 4 bytes to set. We
116 * may have an unaligned pointer as well.
117 */
1185: tst r2, #2
119 strbne r1, [ip], #1
120 strbne r1, [ip], #1
121 tst r2, #1
122 strbne r1, [ip], #1
123 ret lr
124
1256: subs r2, r2, #4 @ 1 do we have enough
126 blt 5b @ 1 bytes to align with?
127 cmp r3, #2 @ 1
128 strblt r1, [ip], #1 @ 1
129 strble r1, [ip], #1 @ 1
130 strb r1, [ip], #1 @ 1
131 add r2, r2, r3 @ 1 (r2 = r2 - (4 - r3))
132 b 1b
133UNWIND( .fnend )
134ENDPROC(memset)
135ENDPROC(mmioset)
136ENDPROC(__memset)
137
138ENTRY(__memset32)
139UNWIND( .fnstart )
140 mov r3, r1 @ copy r1 to r3 and fall into memset64
141UNWIND( .fnend )
142ENDPROC(__memset32)
143ENTRY(__memset64)
144UNWIND( .fnstart )
145 mov ip, r0 @ preserve r0 as return value
146 b 7b @ jump into the middle of memset
147UNWIND( .fnend )
148ENDPROC(__memset64)