1/*
2 * Copyright (C) 2011 Richard Weinberger <richrd@nod.at>
3 * Mostly copied from arch/x86/lib/delay.c
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
8 */
9
10#include <linux/module.h>
11#include <linux/kernel.h>
12#include <linux/delay.h>
13#include <asm/param.h>
14
15void __delay(unsigned long loops)
16{
17	asm volatile(
18		"test %0,%0\n"
19		"jz 3f\n"
20		"jmp 1f\n"
21
22		".align 16\n"
23		"1: jmp 2f\n"
24
25		".align 16\n"
26		"2: dec %0\n"
27		" jnz 2b\n"
28		"3: dec %0\n"
29
30		: /* we don't need output */
31		: "a" (loops)
32	);
33}
34EXPORT_SYMBOL(__delay);
35
36inline void __const_udelay(unsigned long xloops)
37{
38	int d0;
39
40	xloops *= 4;
41	asm("mull %%edx"
42		: "=d" (xloops), "=&a" (d0)
43		: "1" (xloops), "0"
44		(loops_per_jiffy * (HZ/4)));
45
46	__delay(++xloops);
47}
48EXPORT_SYMBOL(__const_udelay);
49
50void __udelay(unsigned long usecs)
51{
52	__const_udelay(usecs * 0x000010c7); /* 2**32 / 1000000 (rounded up) */
53}
54EXPORT_SYMBOL(__udelay);
55
56void __ndelay(unsigned long nsecs)
57{
58	__const_udelay(nsecs * 0x00005); /* 2**32 / 1000000000 (rounded up) */
59}
60EXPORT_SYMBOL(__ndelay);
61