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

 
 1/*
 2 * OpenRISC Linux
 3 *
 4 * Linux architectural port borrowing liberally from similar works of
 5 * others.  All original copyrights apply as per the original source
 6 * declaration.
 7 *
 8 * Modifications for the OpenRISC architecture:
 9 * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
10 *
11 *      This program is free software; you can redistribute it and/or
12 *      modify it under the terms of the GNU General Public License
13 *      version 2 as published by the Free Software Foundation
14 *
15 * Precise Delay Loops
16 */
17
18#include <linux/kernel.h>
19#include <linux/module.h>
20#include <linux/init.h>
 
21#include <asm/delay.h>
22#include <asm/timex.h>
23#include <asm/processor.h>
24
25int read_current_timer(unsigned long *timer_value)
26{
27	*timer_value = mfspr(SPR_TTCR);
28	return 0;
29}
30
31void __delay(unsigned long cycles)
32{
33	cycles_t start = get_cycles();
34
35	while ((get_cycles() - start) < cycles)
36		cpu_relax();
37}
38EXPORT_SYMBOL(__delay);
39
40inline void __const_udelay(unsigned long xloops)
41{
42	unsigned long long loops;
43
44	loops = (unsigned long long)xloops * loops_per_jiffy * HZ;
45
46	__delay(loops >> 32);
47}
48EXPORT_SYMBOL(__const_udelay);
49
50void __udelay(unsigned long usecs)
51{
52	__const_udelay(usecs * 0x10C7UL); /* 2**32 / 1000000 (rounded up) */
53}
54EXPORT_SYMBOL(__udelay);
55
56void __ndelay(unsigned long nsecs)
57{
58	__const_udelay(nsecs * 0x5UL); /* 2**32 / 1000000000 (rounded up) */
59}
60EXPORT_SYMBOL(__ndelay);