OpenCloudOS-Kernel/arch/arm26/lib/clearbit.S

32 lines
735 B
ArmAsm

/*
* linux/arch/arm26/lib/clearbit.S
*
* Copyright (C) 1995-1996 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>
.text
/*
* Purpose : Function to clear a bit
* Prototype: int clear_bit(int bit, void *addr)
*/
ENTRY(_clear_bit_be)
eor r0, r0, #0x18 @ big endian byte ordering
ENTRY(_clear_bit_le)
and r2, r0, #7
mov r3, #1
mov r3, r3, lsl r2
save_and_disable_irqs ip, r2
ldrb r2, [r1, r0, lsr #3]
bic r2, r2, r3
strb r2, [r1, r0, lsr #3]
restore_irqs ip
RETINSTR(mov,pc,lr)