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/*
* linux/arch/arm/lib/delay.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
LC0: .word SYMBOL_NAME(loops_per_jiffy)
/*
* 0 <= r0 <= 2000
*/
ENTRY(udelay)
mov r2, #0x6800
orr r2, r2, #0x00db
mul r1, r0, r2
ldr r2, LC0
ldr r2, [r2]
mov r1, r1, lsr #11
mov r2, r2, lsr #11
mul r0, r1, r2
movs r0, r0, lsr #6
RETINSTR(moveq,pc,lr)
/*
* loops = (r0 * 0x10c6 * 100 * loops_per_jiffie) / 2^32
*/
@ Delay routine
ENTRY(__delay)
subs r0, r0, #1
RETINSTR(movcc,pc,lr)
subs r0, r0, #1
RETINSTR(movcc,pc,lr)
subs r0, r0, #1
RETINSTR(movcc,pc,lr)
subs r0, r0, #1
RETINSTR(movcc,pc,lr)
subs r0, r0, #1
RETINSTR(movcc,pc,lr)
subs r0, r0, #1
RETINSTR(movcc,pc,lr)
subs r0, r0, #1
RETINSTR(movcc,pc,lr)
subs r0, r0, #1
bcs SYMBOL_NAME(__delay)
RETINSTR(mov,pc,lr)
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