xref: /openbmc/linux/arch/powerpc/boot/string.S (revision 64c70b1c)
1/*
2 * Copyright (C) Paul Mackerras 1997.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
8 *
9 * NOTE: this code runs in 32 bit mode and is packaged as ELF32.
10 */
11
12#include "ppc_asm.h"
13
14	.text
15	.globl	strcpy
16strcpy:
17	addi	r5,r3,-1
18	addi	r4,r4,-1
191:	lbzu	r0,1(r4)
20	cmpwi	0,r0,0
21	stbu	r0,1(r5)
22	bne	1b
23	blr
24
25	.globl	strncpy
26strncpy:
27	cmpwi	0,r5,0
28	beqlr
29	mtctr	r5
30	addi	r6,r3,-1
31	addi	r4,r4,-1
321:	lbzu	r0,1(r4)
33	cmpwi	0,r0,0
34	stbu	r0,1(r6)
35	bdnzf	2,1b		/* dec ctr, branch if ctr != 0 && !cr0.eq */
36	blr
37
38	.globl	strcat
39strcat:
40	addi	r5,r3,-1
41	addi	r4,r4,-1
421:	lbzu	r0,1(r5)
43	cmpwi	0,r0,0
44	bne	1b
45	addi	r5,r5,-1
461:	lbzu	r0,1(r4)
47	cmpwi	0,r0,0
48	stbu	r0,1(r5)
49	bne	1b
50	blr
51
52	.globl	strcmp
53strcmp:
54	addi	r5,r3,-1
55	addi	r4,r4,-1
561:	lbzu	r3,1(r5)
57	cmpwi	1,r3,0
58	lbzu	r0,1(r4)
59	subf.	r3,r0,r3
60	beqlr	1
61	beq	1b
62	blr
63
64	.globl	strlen
65strlen:
66	addi	r4,r3,-1
671:	lbzu	r0,1(r4)
68	cmpwi	0,r0,0
69	bne	1b
70	subf	r3,r3,r4
71	blr
72
73	.globl	memset
74memset:
75	rlwimi	r4,r4,8,16,23
76	rlwimi	r4,r4,16,0,15
77	addi	r6,r3,-4
78	cmplwi	0,r5,4
79	blt	7f
80	stwu	r4,4(r6)
81	beqlr
82	andi.	r0,r6,3
83	add	r5,r0,r5
84	subf	r6,r0,r6
85	rlwinm	r0,r5,32-2,2,31
86	mtctr	r0
87	bdz	6f
881:	stwu	r4,4(r6)
89	bdnz	1b
906:	andi.	r5,r5,3
917:	cmpwi	0,r5,0
92	beqlr
93	mtctr	r5
94	addi	r6,r6,3
958:	stbu	r4,1(r6)
96	bdnz	8b
97	blr
98
99	.globl	memmove
100memmove:
101	cmplw	0,r3,r4
102	bgt	backwards_memcpy
103	/* fall through */
104
105	.globl	memcpy
106memcpy:
107	rlwinm.	r7,r5,32-3,3,31		/* r7 = r5 >> 3 */
108	addi	r6,r3,-4
109	addi	r4,r4,-4
110	beq	3f			/* if less than 8 bytes to do */
111	andi.	r0,r6,3			/* get dest word aligned */
112	mtctr	r7
113	bne	5f
114	andi.	r0,r4,3			/* check src word aligned too */
115	bne	3f
1161:	lwz	r7,4(r4)
117	lwzu	r8,8(r4)
118	stw	r7,4(r6)
119	stwu	r8,8(r6)
120	bdnz	1b
121	andi.	r5,r5,7
1222:	cmplwi	0,r5,4
123	blt	3f
124	lwzu	r0,4(r4)
125	addi	r5,r5,-4
126	stwu	r0,4(r6)
1273:	cmpwi	0,r5,0
128	beqlr
129	mtctr	r5
130	addi	r4,r4,3
131	addi	r6,r6,3
1324:	lbzu	r0,1(r4)
133	stbu	r0,1(r6)
134	bdnz	4b
135	blr
1365:	subfic	r0,r0,4
137	cmpw	cr1,r0,r5
138	add	r7,r0,r4
139	andi.	r7,r7,3			/* will source be word-aligned too? */
140	ble	cr1,3b
141	bne	3b			/* do byte-by-byte if not */
142	mtctr	r0
1436:	lbz	r7,4(r4)
144	addi	r4,r4,1
145	stb	r7,4(r6)
146	addi	r6,r6,1
147	bdnz	6b
148	subf	r5,r0,r5
149	rlwinm.	r7,r5,32-3,3,31
150	beq	2b
151	mtctr	r7
152	b	1b
153
154	.globl	backwards_memcpy
155backwards_memcpy:
156	rlwinm.	r7,r5,32-3,3,31		/* r7 = r5 >> 3 */
157	add	r6,r3,r5
158	add	r4,r4,r5
159	beq	3f
160	andi.	r0,r6,3
161	mtctr	r7
162	bne	5f
163	andi.	r0,r4,3
164	bne	3f
1651:	lwz	r7,-4(r4)
166	lwzu	r8,-8(r4)
167	stw	r7,-4(r6)
168	stwu	r8,-8(r6)
169	bdnz	1b
170	andi.	r5,r5,7
1712:	cmplwi	0,r5,4
172	blt	3f
173	lwzu	r0,-4(r4)
174	subi	r5,r5,4
175	stwu	r0,-4(r6)
1763:	cmpwi	0,r5,0
177	beqlr
178	mtctr	r5
1794:	lbzu	r0,-1(r4)
180	stbu	r0,-1(r6)
181	bdnz	4b
182	blr
1835:	cmpw	cr1,r0,r5
184	subf	r7,r0,r4
185	andi.	r7,r7,3
186	ble	cr1,3b
187	bne	3b
188	mtctr	r0
1896:	lbzu	r7,-1(r4)
190	stbu	r7,-1(r6)
191	bdnz	6b
192	subf	r5,r0,r5
193	rlwinm.	r7,r5,32-3,3,31
194	beq	2b
195	mtctr	r7
196	b	1b
197
198	.globl	memcmp
199memcmp:
200	cmpwi	0,r5,0
201	blelr
202	mtctr	r5
203	addi	r6,r3,-1
204	addi	r4,r4,-1
2051:	lbzu	r3,1(r6)
206	lbzu	r0,1(r4)
207	subf.	r3,r0,r3
208	bdnzt	2,1b
209	blr
210
211
212/*
213 * Flush the dcache and invalidate the icache for a range of addresses.
214 *
215 * flush_cache(addr, len)
216 */
217	.global	flush_cache
218flush_cache:
219	addi	4,4,0x1f	/* len = (len + 0x1f) / 0x20 */
220	rlwinm.	4,4,27,5,31
221	mtctr	4
222	beqlr
2231:	dcbf	0,3
224	icbi	0,3
225	addi	3,3,0x20
226	bdnz	1b
227	sync
228	isync
229	blr
230
231