xref: /openbmc/linux/arch/arm/lib/io-readsl.S (revision 2cf1c348)
1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 *  linux/arch/arm/lib/io-readsl.S
4 *
5 *  Copyright (C) 1995-2000 Russell King
6 */
7#include <linux/linkage.h>
8#include <asm/assembler.h>
9
10ENTRY(__raw_readsl)
11		teq	r2, #0		@ do we have to check for the zero len?
12		reteq	lr
13		ands	ip, r1, #3
14		bne	3f
15
16		subs	r2, r2, #4
17		bmi	2f
18		stmfd	sp!, {r4, lr}
191:		ldr	r3, [r0, #0]
20		ldr	r4, [r0, #0]
21		ldr	ip, [r0, #0]
22		ldr	lr, [r0, #0]
23		subs	r2, r2, #4
24		stmia	r1!, {r3, r4, ip, lr}
25		bpl	1b
26		ldmfd	sp!, {r4, lr}
272:		movs	r2, r2, lsl #31
28		ldrcs	r3, [r0, #0]
29		ldrcs	ip, [r0, #0]
30		stmiacs	r1!, {r3, ip}
31		ldrne	r3, [r0, #0]
32		strne	r3, [r1, #0]
33		ret	lr
34
353:		ldr	r3, [r0]
36		cmp	ip, #2
37		mov	ip, r3, get_byte_0
38		strb	ip, [r1], #1
39		bgt	6f
40		mov	ip, r3, get_byte_1
41		strb	ip, [r1], #1
42		beq	5f
43		mov	ip, r3, get_byte_2
44		strb	ip, [r1], #1
45
464:		subs	r2, r2, #1
47		mov	ip, r3, lspull #24
48		ldrne	r3, [r0]
49		orrne	ip, ip, r3, lspush #8
50		strne	ip, [r1], #4
51		bne	4b
52		b	8f
53
545:		subs	r2, r2, #1
55		mov	ip, r3, lspull #16
56		ldrne	r3, [r0]
57		orrne	ip, ip, r3, lspush #16
58		strne	ip, [r1], #4
59		bne	5b
60		b	7f
61
626:		subs	r2, r2, #1
63		mov	ip, r3, lspull #8
64		ldrne	r3, [r0]
65		orrne	ip, ip, r3, lspush #24
66		strne	ip, [r1], #4
67		bne	6b
68
69		mov	r3, ip, get_byte_2
70		strb	r3, [r1, #2]
717:		mov	r3, ip, get_byte_1
72		strb	r3, [r1, #1]
738:		mov	r3, ip, get_byte_0
74		strb	r3, [r1, #0]
75		ret	lr
76ENDPROC(__raw_readsl)
77