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Haavard Skinnemoen5f97f7f2006-09-25 23:32:13 -07001/*
2 * Precise Delay Loops for avr32
3 *
4 * Copyright (C) 1993 Linus Torvalds
5 * Copyright (C) 1997 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
6 * Copyright (C) 2005-2006 Atmel Corporation
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12
13#include <linux/delay.h>
14#include <linux/module.h>
Haavard Skinnemoen3fc0eb42006-12-08 12:55:03 +010015#include <linux/param.h>
Haavard Skinnemoen5f97f7f2006-09-25 23:32:13 -070016#include <linux/types.h>
17
Haavard Skinnemoen5f97f7f2006-09-25 23:32:13 -070018#include <asm/processor.h>
19#include <asm/sysreg.h>
20
21int read_current_timer(unsigned long *timer_value)
22{
23 *timer_value = sysreg_read(COUNT);
24 return 0;
25}
26
27void __delay(unsigned long loops)
28{
29 unsigned bclock, now;
30
31 bclock = sysreg_read(COUNT);
32 do {
33 now = sysreg_read(COUNT);
34 } while ((now - bclock) < loops);
35}
36
37inline void __const_udelay(unsigned long xloops)
38{
39 unsigned long long loops;
40
41 asm("mulu.d %0, %1, %2"
42 : "=r"(loops)
43 : "r"(current_cpu_data.loops_per_jiffy * HZ), "r"(xloops));
44 __delay(loops >> 32);
45}
46
47void __udelay(unsigned long usecs)
48{
49 __const_udelay(usecs * 0x000010c7); /* 2**32 / 1000000 (rounded up) */
50}
51
52void __ndelay(unsigned long nsecs)
53{
54 __const_udelay(nsecs * 0x00005); /* 2**32 / 1000000000 (rounded up) */
55}