xref: /openbmc/linux/arch/arm/lib/changebit.S (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
1/*
2 *  linux/arch/arm/lib/changebit.S
3 *
4 *  Copyright (C) 1995-1996 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                .text
13
14/* Purpose  : Function to change a bit
15 * Prototype: int change_bit(int bit, void *addr)
16 */
17ENTRY(_change_bit_be)
18		eor	r0, r0, #0x18		@ big endian byte ordering
19ENTRY(_change_bit_le)
20		and	r2, r0, #7
21		mov	r3, #1
22		mov	r3, r3, lsl r2
23		save_and_disable_irqs ip, r2
24		ldrb	r2, [r1, r0, lsr #3]
25		eor	r2, r2, r3
26		strb	r2, [r1, r0, lsr #3]
27		restore_irqs ip
28		RETINSTR(mov,pc,lr)
29