xref: /openbmc/linux/arch/nios2/lib/delay.c (revision d9fd5a71)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright Altera Corporation (C) 2014. All rights reserved.
3  */
4 
5 #include <linux/module.h>
6 #include <asm/delay.h>
7 #include <asm/param.h>
8 #include <asm/processor.h>
9 #include <asm/timex.h>
10 
11 void __delay(unsigned long cycles)
12 {
13 	cycles_t start = get_cycles();
14 
15 	while ((get_cycles() - start) < cycles)
16 		cpu_relax();
17 }
18 EXPORT_SYMBOL(__delay);
19 
20 void __const_udelay(unsigned long xloops)
21 {
22 	u64 loops;
23 
24 	loops = (u64)xloops * loops_per_jiffy * HZ;
25 
26 	__delay(loops >> 32);
27 }
28 EXPORT_SYMBOL(__const_udelay);
29 
30 void __udelay(unsigned long usecs)
31 {
32 	__const_udelay(usecs * 0x10C7UL); /* 2**32 / 1000000 (rounded up) */
33 }
34 EXPORT_SYMBOL(__udelay);
35 
36 void __ndelay(unsigned long nsecs)
37 {
38 	__const_udelay(nsecs * 0x5UL); /* 2**32 / 1000000000 (rounded up) */
39 }
40 EXPORT_SYMBOL(__ndelay);
41