29 lines
733 B
ArmAsm
29 lines
733 B
ArmAsm
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/*
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* linux/arch/arm/lib/changebit.S
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*
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* Copyright (C) 1995-1996 Russell King
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/linkage.h>
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#include <asm/assembler.h>
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.text
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/* Purpose : Function to change a bit
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* Prototype: int change_bit(int bit, void *addr)
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*/
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ENTRY(_change_bit_be)
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eor r0, r0, #0x18 @ big endian byte ordering
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ENTRY(_change_bit_le)
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and r2, r0, #7
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mov r3, #1
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mov r3, r3, lsl r2
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save_and_disable_irqs ip, r2
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ldrb r2, [r1, r0, lsr #3]
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eor r2, r2, r3
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strb r2, [r1, r0, lsr #3]
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restore_irqs ip
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RETINSTR(mov,pc,lr)
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