kernel-ark/arch/arm/lib/io-writesw-armv4.S
Nicolas Pitre aeabbbbe12 [PATCH] ARM: 2705/1: fix writesw for misaligned source pointer
Patch from Nicolas Pitre

Signed-off-by: Nicolas Pitre
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-06-08 19:00:16 +01:00

96 lines
1.6 KiB
ArmAsm

/*
* linux/arch/arm/lib/io-writesw-armv4.S
*
* Copyright (C) 1995-2000 Russell King
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
.macro outword, rd
#ifndef __ARMEB__
strh \rd, [r0]
mov \rd, \rd, lsr #16
strh \rd, [r0]
#else
mov lr, \rd, lsr #16
strh lr, [r0]
strh \rd, [r0]
#endif
.endm
.outsw_align: movs ip, r1, lsl #31
bne .outsw_noalign
ldrh r3, [r1], #2
sub r2, r2, #1
strh r3, [r0]
ENTRY(__raw_writesw)
teq r2, #0
moveq pc, lr
ands r3, r1, #3
bne .outsw_align
stmfd sp!, {r4, r5, lr}
subs r2, r2, #8
bmi .no_outsw_8
.outsw_8_lp: ldmia r1!, {r3, r4, r5, ip}
subs r2, r2, #8
outword r3
outword r4
outword r5
outword ip
bpl .outsw_8_lp
.no_outsw_8: tst r2, #4
beq .no_outsw_4
ldmia r1!, {r3, ip}
outword r3
outword ip
.no_outsw_4: movs r2, r2, lsl #31
bcc .no_outsw_2
ldr r3, [r1], #4
outword r3
.no_outsw_2: ldrneh r3, [r1]
strneh r3, [r0]
ldmfd sp!, {r4, r5, pc}
#ifdef __ARMEB__
#define pull_hbyte0 lsl #8
#define push_hbyte1 lsr #24
#else
#define pull_hbyte0 lsr #24
#define push_hbyte1 lsl #8
#endif
.outsw_noalign: ldr r3, [r1, -r3]!
subcs r2, r2, #1
bcs 2f
subs r2, r2, #2
bmi 3f
1: mov ip, r3, lsr #8
strh ip, [r0]
2: mov ip, r3, pull_hbyte0
ldr r3, [r1, #4]!
subs r2, r2, #2
orr ip, ip, r3, push_hbyte1
strh ip, [r0]
bpl 1b
tst r2, #1
3: movne ip, r3, lsr #8
strneh ip, [r0]
mov pc, lr