File: [Development] / linux-2.6-xfs / arch / arm / lib / delay.S (download)
Revision 1.3, Mon Dec 5 21:19:08 2005 UTC (11 years, 10 months ago) by nathans.longdrop.melbourne.sgi.com
Branch: MAIN
Changes since 1.2: +2 -2
lines
Merge up to 2.6.15-rc5.
Merge of 2.6.x-xfs-melb:linux:24672a by kenmcd.
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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)