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/*
* linux/arch/arm/lib/delay.S
*
* Copyright (C) 1995-2003 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>
#include <asm/delay.h>
.text
/*
* See linux/include/asm-arm/delay.h for a description of the maths.
*/
#if NDELAY_FACTOR > 255
#error NDELAY_FACTOR out of range
#endif
#if UDELAY_FACTOR > 65535
#error UDELAY_FACTOR out of range
#endif
LC0: .word SYMBOL_NAME(loops_per_jiffy)
ENTRY(__const_delay)
ldr r3, LC0
mov r1, r0, lsr #11
ldr r2, [r3, #0]
b 2f
ENTRY(__ndelay)
mov r2, #NDELAY_FACTOR
b 1f
ENTRY(__udelay)
mov r2, #UDELAY_FACTOR & 0xff00
orr r2, r2, #UDELAY_FACTOR & 0x00ff
1: ldr r3, LC0
mul r1, r0, r2
ldr r2, [r3, #0]
mov r1, r1, lsr #11
2: mov r2, r2, lsr #12
mul r0, r1, r2
movs r0, r0, lsr #5
RETINSTR(moveq,pc,lr)
/*
* loops = (r0 * 0x10c6 * HZ * loops_per_jiffy) / 2^32
*
* Oh, if only we had a cycle counter...
*/
ENTRY(__delay)
subs r0, r0, #1
bcs SYMBOL_NAME(__delay)
RETINSTR(mov,pc,lr)
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