/* | |
* linux/arch/arm26/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 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_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) |