Linux-2.6.12-rc2
[linux-2.6.git] / arch / arm / lib / io-writesb.S
1 /*
2  *  linux/arch/arm/lib/io-writesb.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
13                 .macro  outword, rd
14 #ifndef __ARMEB__
15                 strb    \rd, [r0]
16                 mov     \rd, \rd, lsr #8
17                 strb    \rd, [r0]
18                 mov     \rd, \rd, lsr #8
19                 strb    \rd, [r0]
20                 mov     \rd, \rd, lsr #8
21                 strb    \rd, [r0]
22 #else
23                 mov     lr, \rd, lsr #24
24                 strb    lr, [r0]
25                 mov     lr, \rd, lsr #16
26                 strb    lr, [r0]
27                 mov     lr, \rd, lsr #8
28                 strb    lr, [r0]
29                 strb    \rd, [r0]
30 #endif
31                 .endm
32
33 .outsb_align:   rsb     ip, ip, #4
34                 cmp     ip, r2
35                 movgt   ip, r2
36                 cmp     ip, #2
37                 ldrb    r3, [r1], #1
38                 strb    r3, [r0]
39                 ldrgeb  r3, [r1], #1
40                 strgeb  r3, [r0]
41                 ldrgtb  r3, [r1], #1
42                 strgtb  r3, [r0]
43                 subs    r2, r2, ip
44                 bne     .outsb_aligned
45
46 ENTRY(__raw_writesb)
47                 teq     r2, #0          @ do we have to check for the zero len?
48                 moveq   pc, lr
49                 ands    ip, r1, #3
50                 bne     .outsb_align
51
52 .outsb_aligned: stmfd   sp!, {r4, r5, lr}
53
54                 subs    r2, r2, #16
55                 bmi     .outsb_no_16
56
57 .outsb_16_lp:   ldmia   r1!, {r3, r4, r5, ip}
58                 outword r3
59                 outword r4
60                 outword r5
61                 outword ip
62                 subs    r2, r2, #16
63                 bpl     .outsb_16_lp
64
65                 tst     r2, #15
66                 LOADREGS(eqfd, sp!, {r4, r5, pc})
67
68 .outsb_no_16:   tst     r2, #8
69                 beq     .outsb_no_8
70
71                 ldmia   r1!, {r3, r4}
72                 outword r3
73                 outword r4
74
75 .outsb_no_8:    tst     r2, #4
76                 beq     .outsb_no_4
77
78                 ldr     r3, [r1], #4
79                 outword r3
80
81 .outsb_no_4:    ands    r2, r2, #3
82                 LOADREGS(eqfd, sp!, {r4, r5, pc})
83
84                 cmp     r2, #2
85                 ldrb    r3, [r1], #1
86                 strb    r3, [r0]
87                 ldrgeb  r3, [r1], #1
88                 strgeb  r3, [r0]
89                 ldrgtb  r3, [r1]
90                 strgtb  r3, [r0]
91
92                 LOADREGS(fd, sp!, {r4, r5, pc})