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/*
* include/asm-arm/macro.h
*
* Copyright (C) 2009 Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#ifndef __ASM_ARM_MACRO_H__
#define __ASM_ARM_MACRO_H__
#ifdef __ASSEMBLY__
/*
* These macros provide a convenient way to write 8, 16 and 32 bit data
* to any address.
* Registers r4 and r5 are used, any data in these registers are
* overwritten by the macros.
* The macros are valid for any ARM architecture, they do not implement
* any memory barriers so caution is recommended when using these when the
* caches are enabled or on a multi-core system.
*/
.macro write32, addr, data
ldr r4, =\addr
ldr r5, =\data
str r5, [r4]
.endm
.macro write16, addr, data
ldr r4, =\addr
ldrh r5, =\data
strh r5, [r4]
.endm
.macro write8, addr, data
ldr r4, =\addr
ldrb r5, =\data
strb r5, [r4]
.endm
/*
* This macro generates a loop that can be used for delays in the code.
* Register r4 is used, any data in this register is overwritten by the
* macro.
* The macro is valid for any ARM architeture. The actual time spent in the
* loop will vary from CPU to CPU though.
*/
.macro wait_timer, time
ldr r4, =\time
1:
nop
subs r4, r4, #1
bcs 1b
.endm
#endif /* __ASSEMBLY__ */
#endif /* __ASM_ARM_MACRO_H__ */
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