xref: /openbmc/linux/arch/arm/lib/io-writesw-armv4.S (revision 82003e04)
1/*
2 *  linux/arch/arm/lib/io-writesw-armv4.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#include <asm/export.h>
13
14		.macro	outword, rd
15#ifndef __ARMEB__
16		strh	\rd, [r0]
17		mov	\rd, \rd, lsr #16
18		strh	\rd, [r0]
19#else
20		mov	lr, \rd, lsr #16
21		strh	lr, [r0]
22		strh	\rd, [r0]
23#endif
24		.endm
25
26.Loutsw_align:	movs	ip, r1, lsl #31
27		bne	.Loutsw_noalign
28
29		ldrh	r3, [r1], #2
30		sub	r2, r2, #1
31		strh	r3, [r0]
32
33ENTRY(__raw_writesw)
34		teq	r2, #0
35		reteq	lr
36		ands	r3, r1, #3
37		bne	.Loutsw_align
38
39		stmfd	sp!, {r4, r5, lr}
40
41		subs	r2, r2, #8
42		bmi	.Lno_outsw_8
43
44.Loutsw_8_lp:	ldmia	r1!, {r3, r4, r5, ip}
45		subs	r2, r2, #8
46		outword	r3
47		outword	r4
48		outword	r5
49		outword	ip
50		bpl	.Loutsw_8_lp
51
52.Lno_outsw_8:	tst	r2, #4
53		beq	.Lno_outsw_4
54
55		ldmia	r1!, {r3, ip}
56		outword	r3
57		outword	ip
58
59.Lno_outsw_4:	movs	r2, r2, lsl #31
60		bcc	.Lno_outsw_2
61
62		ldr	r3, [r1], #4
63		outword	r3
64
65.Lno_outsw_2:	ldrneh	r3, [r1]
66		strneh	r3, [r0]
67
68		ldmfd	sp!, {r4, r5, pc}
69
70#ifdef __ARMEB__
71#define pull_hbyte0	lsl #8
72#define push_hbyte1	lsr #24
73#else
74#define pull_hbyte0	lsr #24
75#define push_hbyte1	lsl #8
76#endif
77
78.Loutsw_noalign:
79 ARM(		ldr	r3, [r1, -r3]!	)
80 THUMB(		rsb	r3, r3, #0	)
81 THUMB(		ldr	r3, [r1, r3]	)
82 THUMB(		sub	r1, r3		)
83		subcs	r2, r2, #1
84		bcs	2f
85		subs	r2, r2, #2
86		bmi	3f
87
881:		mov	ip, r3, lsr #8
89		strh	ip, [r0]
902:		mov	ip, r3, pull_hbyte0
91		ldr	r3, [r1, #4]!
92		subs	r2, r2, #2
93		orr	ip, ip, r3, push_hbyte1
94		strh	ip, [r0]
95		bpl	1b
96
97		tst	r2, #1
983:		movne	ip, r3, lsr #8
99		strneh	ip, [r0]
100		ret	lr
101ENDPROC(__raw_writesw)
102EXPORT_SYMBOL(__raw_writesw)
103