testchangebit.S
上传用户:lgb322
上传日期:2013-02-24
资源大小:30529k
文件大小:1k
- /*
- * linux/arch/arm/lib/testchangebit.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
- ENTRY(test_and_change_bit)
- add r1, r1, r0, lsr #3
- and r3, r0, #7
- mov r0, #1
- save_and_disable_irqs ip, r2
- ldrb r2, [r1]
- tst r2, r0, lsl r3
- eor r2, r2, r0, lsl r3
- strb r2, [r1]
- restore_irqs ip
- moveq r0, #0
- RETINSTR(mov,pc,lr)