blob: 75a9121cb23f69f13d5cb1a389daa46d511c5ee3 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/arch/arm/lib/io-readsl.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#include <linux/linkage.h>
11#include <asm/assembler.h>
12
13ENTRY(__raw_readsl)
14 teq r2, #0 @ do we have to check for the zero len?
15 moveq pc, lr
16 ands ip, r1, #3
17 bne 3f
18
19 subs r2, r2, #4
20 bmi 2f
21 stmfd sp!, {r4, lr}
221: ldr r3, [r0, #0]
23 ldr r4, [r0, #0]
24 ldr ip, [r0, #0]
25 ldr lr, [r0, #0]
26 subs r2, r2, #4
27 stmia r1!, {r3, r4, ip, lr}
28 bpl 1b
29 ldmfd sp!, {r4, lr}
302: movs r2, r2, lsl #31
31 ldrcs r3, [r0, #0]
32 ldrcs ip, [r0, #0]
33 stmcsia r1!, {r3, ip}
34 ldrne r3, [r0, #0]
35 strne r3, [r1, #0]
36 mov pc, lr
37
383: ldr r3, [r0]
39 cmp ip, #2
40 mov ip, r3, get_byte_0
41 strb ip, [r1], #1
42 bgt 6f
43 mov ip, r3, get_byte_1
44 strb ip, [r1], #1
45 beq 5f
46 mov ip, r3, get_byte_2
47 strb ip, [r1], #1
48
494: subs r2, r2, #1
50 mov ip, r3, pull #24
51 ldrne r3, [r0]
52 orrne ip, ip, r3, push #8
53 strne ip, [r1], #4
54 bne 4b
55 b 8f
56
575: subs r2, r2, #1
58 mov ip, r3, pull #16
59 ldrne r3, [r0]
60 orrne ip, ip, r3, push #16
61 strne ip, [r1], #4
62 bne 5b
63 b 7f
64
656: subs r2, r2, #1
66 mov ip, r3, pull #8
67 ldrne r3, [r0]
68 orrne ip, ip, r3, push #24
69 strne ip, [r1], #4
70 bne 6b
71
72 mov r3, ip, get_byte_2
73 strb r3, [r1, #2]
747: mov r3, ip, get_byte_1
75 strb r3, [r1, #1]
768: mov r3, ip, get_byte_0
77 strb r3, [r1, #0]
78 mov pc, lr