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gerrit.devboardsforandroid.linaro.org / platform / external / u-boot / 6173c45b21ca584fd691b21dc81a44d852d4bdce / . / arch / arm / lib / memcpy.S
blob: f655256b5d1514f949b880c322cb225a73cd538b [file] [log] [blame]
Matthias Weisserd8834a12011-03-10 21:36:32 +0000[diff] [blame]1/*
2 * linux/arch/arm/lib/memcpy.S
3 *
4 * Author: Nicolas Pitre
5 * Created: Sep 28, 2005
6 * Copyright: MontaVista Software, Inc.
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12
13#include <asm/assembler.h>
14
15#define W(instr) instr
16
17#define LDR1W_SHIFT 0
18#define STR1W_SHIFT 0
19
20 .macro ldr1w ptr reg abort
21 W(ldr) \reg, [\ptr], #4
22 .endm
23
24 .macro ldr4w ptr reg1 reg2 reg3 reg4 abort
25 ldmia \ptr!, {\reg1, \reg2, \reg3, \reg4}
26 .endm
27
28 .macro ldr8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
29 ldmia \ptr!, {\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8}
30 .endm
31
32 .macro ldr1b ptr reg cond=al abort
33 ldr\cond\()b \reg, [\ptr], #1
34 .endm
35
36 .macro str1w ptr reg abort
37 W(str) \reg, [\ptr], #4
38 .endm
39
40 .macro str8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
41 stmia \ptr!, {\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8}
42 .endm
43
44 .macro str1b ptr reg cond=al abort
45 str\cond\()b \reg, [\ptr], #1
46 .endm
47
48 .macro enter reg1 reg2
49 stmdb sp!, {r0, \reg1, \reg2}
50 .endm
51
52 .macro exit reg1 reg2
53 ldmfd sp!, {r0, \reg1, \reg2}
54 .endm
55
56 .text
57
58/* Prototype: void *memcpy(void *dest, const void *src, size_t n); */
59
60.globl memcpy
61memcpy:
62
Matthias Weisser34fe8282011-05-22 23:06:50 +0000[diff] [blame]63 cmp r0, r1
64 moveq pc, lr
65
Matthias Weisserd8834a12011-03-10 21:36:32 +0000[diff] [blame]66 enter r4, lr
67
68 subs r2, r2, #4
69 blt 8f
70 ands ip, r0, #3
71 PLD( pld [r1, #0] )
72 bne 9f
73 ands ip, r1, #3
74 bne 10f
75
761: subs r2, r2, #(28)
77 stmfd sp!, {r5 - r8}
78 blt 5f
79
80 CALGN( ands ip, r0, #31 )
81 CALGN( rsb r3, ip, #32 )
82 CALGN( sbcnes r4, r3, r2 ) @ C is always set here
83 CALGN( bcs 2f )
84 CALGN( adr r4, 6f )
85 CALGN( subs r2, r2, r3 ) @ C gets set
86 CALGN( add pc, r4, ip )
87
88 PLD( pld [r1, #0] )
892: PLD( subs r2, r2, #96 )
90 PLD( pld [r1, #28] )
91 PLD( blt 4f )
92 PLD( pld [r1, #60] )
93 PLD( pld [r1, #92] )
94
953: PLD( pld [r1, #124] )
964: ldr8w r1, r3, r4, r5, r6, r7, r8, ip, lr, abort=20f
97 subs r2, r2, #32
98 str8w r0, r3, r4, r5, r6, r7, r8, ip, lr, abort=20f
99 bge 3b
100 PLD( cmn r2, #96 )
101 PLD( bge 4b )
102
1035: ands ip, r2, #28
104 rsb ip, ip, #32
105#if LDR1W_SHIFT > 0
106 lsl ip, ip, #LDR1W_SHIFT
107#endif
108 addne pc, pc, ip @ C is always clear here
109 b 7f
1106:
111 .rept (1 << LDR1W_SHIFT)
112 W(nop)
113 .endr
114 ldr1w r1, r3, abort=20f
115 ldr1w r1, r4, abort=20f
116 ldr1w r1, r5, abort=20f
117 ldr1w r1, r6, abort=20f
118 ldr1w r1, r7, abort=20f
119 ldr1w r1, r8, abort=20f
120 ldr1w r1, lr, abort=20f
121
122#if LDR1W_SHIFT < STR1W_SHIFT
123 lsl ip, ip, #STR1W_SHIFT - LDR1W_SHIFT
124#elif LDR1W_SHIFT > STR1W_SHIFT
125 lsr ip, ip, #LDR1W_SHIFT - STR1W_SHIFT
126#endif
127 add pc, pc, ip
128 nop
129 .rept (1 << STR1W_SHIFT)
130 W(nop)
131 .endr
132 str1w r0, r3, abort=20f
133 str1w r0, r4, abort=20f
134 str1w r0, r5, abort=20f
135 str1w r0, r6, abort=20f
136 str1w r0, r7, abort=20f
137 str1w r0, r8, abort=20f
138 str1w r0, lr, abort=20f
139
140 CALGN( bcs 2b )
141
1427: ldmfd sp!, {r5 - r8}
143
1448: movs r2, r2, lsl #31
145 ldr1b r1, r3, ne, abort=21f
146 ldr1b r1, r4, cs, abort=21f
147 ldr1b r1, ip, cs, abort=21f
148 str1b r0, r3, ne, abort=21f
149 str1b r0, r4, cs, abort=21f
150 str1b r0, ip, cs, abort=21f
151
152 exit r4, pc
153
1549: rsb ip, ip, #4
155 cmp ip, #2
156 ldr1b r1, r3, gt, abort=21f
157 ldr1b r1, r4, ge, abort=21f
158 ldr1b r1, lr, abort=21f
159 str1b r0, r3, gt, abort=21f
160 str1b r0, r4, ge, abort=21f
161 subs r2, r2, ip
162 str1b r0, lr, abort=21f
163 blt 8b
164 ands ip, r1, #3
165 beq 1b
166
16710: bic r1, r1, #3
168 cmp ip, #2
169 ldr1w r1, lr, abort=21f
170 beq 17f
171 bgt 18f
172
173
174 .macro forward_copy_shift pull push
175
176 subs r2, r2, #28
177 blt 14f
178
179 CALGN( ands ip, r0, #31 )
180 CALGN( rsb ip, ip, #32 )
181 CALGN( sbcnes r4, ip, r2 ) @ C is always set here
182 CALGN( subcc r2, r2, ip )
183 CALGN( bcc 15f )
184
18511: stmfd sp!, {r5 - r9}
186
187 PLD( pld [r1, #0] )
188 PLD( subs r2, r2, #96 )
189 PLD( pld [r1, #28] )
190 PLD( blt 13f )
191 PLD( pld [r1, #60] )
192 PLD( pld [r1, #92] )
193
19412: PLD( pld [r1, #124] )
19513: ldr4w r1, r4, r5, r6, r7, abort=19f
196 mov r3, lr, pull #\pull
197 subs r2, r2, #32
198 ldr4w r1, r8, r9, ip, lr, abort=19f
199 orr r3, r3, r4, push #\push
200 mov r4, r4, pull #\pull
201 orr r4, r4, r5, push #\push
202 mov r5, r5, pull #\pull
203 orr r5, r5, r6, push #\push
204 mov r6, r6, pull #\pull
205 orr r6, r6, r7, push #\push
206 mov r7, r7, pull #\pull
207 orr r7, r7, r8, push #\push
208 mov r8, r8, pull #\pull
209 orr r8, r8, r9, push #\push
210 mov r9, r9, pull #\pull
211 orr r9, r9, ip, push #\push
212 mov ip, ip, pull #\pull
213 orr ip, ip, lr, push #\push
214 str8w r0, r3, r4, r5, r6, r7, r8, r9, ip, , abort=19f
215 bge 12b
216 PLD( cmn r2, #96 )
217 PLD( bge 13b )
218
219 ldmfd sp!, {r5 - r9}
220
22114: ands ip, r2, #28
222 beq 16f
223
22415: mov r3, lr, pull #\pull
225 ldr1w r1, lr, abort=21f
226 subs ip, ip, #4
227 orr r3, r3, lr, push #\push
228 str1w r0, r3, abort=21f
229 bgt 15b
230 CALGN( cmp r2, #0 )
231 CALGN( bge 11b )
232
23316: sub r1, r1, #(\push / 8)
234 b 8b
235
236 .endm
237
238
239 forward_copy_shift pull=8 push=24
240
24117: forward_copy_shift pull=16 push=16
242
24318: forward_copy_shift pull=24 push=8