xref: /openbmc/linux/arch/sh/lib/delay.c (revision baa7eb025ab14f3cba2e35c0a8648f9c9f01d24f)
1 /*
2  *	Precise Delay Loops for SuperH
3  *
4  *	Copyright (C) 1999 Niibe Yutaka & Kaz Kojima
5  */
6 
7 #include <linux/sched.h>
8 #include <linux/delay.h>
9 
10 void __delay(unsigned long loops)
11 {
12 	__asm__ __volatile__(
13 		"tst	%0, %0\n\t"
14 		"1:\t"
15 		"bf/s	1b\n\t"
16 		" dt	%0"
17 		: "=r" (loops)
18 		: "0" (loops)
19 		: "t");
20 }
21 
22 inline void __const_udelay(unsigned long xloops)
23 {
24 	xloops *= 4;
25 	__asm__("dmulu.l	%0, %2\n\t"
26 		"sts	mach, %0"
27 		: "=r" (xloops)
28 		: "0" (xloops),
29 		  "r" (cpu_data[raw_smp_processor_id()].loops_per_jiffy * (HZ/4))
30 		: "macl", "mach");
31 	__delay(++xloops);
32 }
33 
34 void __udelay(unsigned long usecs)
35 {
36 	__const_udelay(usecs * 0x000010c6);  /* 2**32 / 1000000 */
37 }
38 
39 void __ndelay(unsigned long nsecs)
40 {
41 	__const_udelay(nsecs * 0x00000005);
42 }
43 
44