xref: /OK3568_Linux_fs/kernel/arch/h8300/lib/delay.c (revision 4882a59341e53eb6f0b4789bf948001014eff981) 
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * delay loops
4*4882a593Smuzhiyun  *
5*4882a593Smuzhiyun  * Copyright (C) 2015 Yoshinori Sato
6*4882a593Smuzhiyun  */
7*4882a593Smuzhiyun 
8*4882a593Smuzhiyun #include <linux/module.h>
9*4882a593Smuzhiyun #include <linux/delay.h>
10*4882a593Smuzhiyun #include <asm/param.h>
11*4882a593Smuzhiyun #include <asm/processor.h>
12*4882a593Smuzhiyun #include <asm/timex.h>
13*4882a593Smuzhiyun 
__delay(unsigned long cycles)14*4882a593Smuzhiyun void __delay(unsigned long cycles)
15*4882a593Smuzhiyun {
16*4882a593Smuzhiyun 	__asm__ volatile ("1: dec.l #1,%0\n\t"
17*4882a593Smuzhiyun 			  "bne 1b":"=r"(cycles):"0"(cycles));
18*4882a593Smuzhiyun }
19*4882a593Smuzhiyun EXPORT_SYMBOL(__delay);
20*4882a593Smuzhiyun 
__const_udelay(unsigned long xloops)21*4882a593Smuzhiyun void __const_udelay(unsigned long xloops)
22*4882a593Smuzhiyun {
23*4882a593Smuzhiyun 	u64 loops;
24*4882a593Smuzhiyun 
25*4882a593Smuzhiyun 	loops = (u64)xloops * loops_per_jiffy * HZ;
26*4882a593Smuzhiyun 
27*4882a593Smuzhiyun 	__delay(loops >> 32);
28*4882a593Smuzhiyun }
29*4882a593Smuzhiyun EXPORT_SYMBOL(__const_udelay);
30*4882a593Smuzhiyun 
__udelay(unsigned long usecs)31*4882a593Smuzhiyun void __udelay(unsigned long usecs)
32*4882a593Smuzhiyun {
33*4882a593Smuzhiyun 	__const_udelay(usecs * 0x10C7UL); /* 2**32 / 1000000 (rounded up) */
34*4882a593Smuzhiyun }
35*4882a593Smuzhiyun EXPORT_SYMBOL(__udelay);
36*4882a593Smuzhiyun 
__ndelay(unsigned long nsecs)37*4882a593Smuzhiyun void __ndelay(unsigned long nsecs)
38*4882a593Smuzhiyun {
39*4882a593Smuzhiyun 	__const_udelay(nsecs * 0x5UL); /* 2**32 / 1000000000 (rounded up) */
40*4882a593Smuzhiyun }
41*4882a593Smuzhiyun EXPORT_SYMBOL(__ndelay);
42