1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
|
// SPDX-License-Identifier: GPL-2.0-only
/*
* OpenRISC Linux
*
* Linux architectural port borrowing liberally from similar works of
* others. All original copyrights apply as per the original source
* declaration.
*
* Modifications for the OpenRISC architecture:
* Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
*
* Precise Delay Loops
*/
#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/init.h>
#include <linux/timex.h>
#include <asm/param.h>
#include <asm/delay.h>
#include <asm/timex.h>
#include <asm/processor.h>
int read_current_timer(unsigned long *timer_value)
{
*timer_value = get_cycles();
return 0;
}
void __delay(unsigned long cycles)
{
cycles_t start = get_cycles();
while ((get_cycles() - start) < cycles)
cpu_relax();
}
EXPORT_SYMBOL(__delay);
inline void __const_udelay(unsigned long xloops)
{
unsigned long long loops;
loops = (unsigned long long)xloops * loops_per_jiffy * HZ;
__delay(loops >> 32);
}
EXPORT_SYMBOL(__const_udelay);
void __udelay(unsigned long usecs)
{
__const_udelay(usecs * 0x10C7UL); /* 2**32 / 1000000 (rounded up) */
}
EXPORT_SYMBOL(__udelay);
void __ndelay(unsigned long nsecs)
{
__const_udelay(nsecs * 0x5UL); /* 2**32 / 1000000000 (rounded up) */
}
EXPORT_SYMBOL(__ndelay);
|
