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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 loops_per_jiffy
/*
* 0 <= r0 <= 2000
*/
ENTRY(__udelay)
mov r2, #0x6800
orr r2, r2, #0x00db
mul r0, r2, r0
ENTRY(__const_udelay) @ 0 <= r0 <= 0x01ffffff
ldr r2, LC0
ldr r2, [r2] @ max = 0x0fffffff
mov r0, r0, lsr #11 @ max = 0x00003fff
mov r2, r2, lsr #11 @ max = 0x0003ffff
mul r0, r2, r0 @ max = 2^32-1
movs r0, r0, lsr #6
RETINSTR(moveq,pc,lr)
/*
* loops = (r0 * 0x10c6 * 100 * loops_per_jiffy) / 2^32
*
* Oh, if only we had a cycle counter...
*/
@ Delay routine
ENTRY(__delay)
subs r0, r0, #1
#if 0
RETINSTR(movls,pc,lr)
subs r0, r0, #1
RETINSTR(movls,pc,lr)
subs r0, r0, #1
RETINSTR(movls,pc,lr)
subs r0, r0, #1
RETINSTR(movls,pc,lr)
subs r0, r0, #1
RETINSTR(movls,pc,lr)
subs r0, r0, #1
RETINSTR(movls,pc,lr)
subs r0, r0, #1
RETINSTR(movls,pc,lr)
subs r0, r0, #1
#endif
bhi __delay
RETINSTR(mov,pc,lr)
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