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
10void __delay(unsigned long loops)
11{
12	__asm__ __volatile__(
13		/*
14		 * ST40-300 appears to have an issue with this code,
15		 * normally taking two cycles each loop, as with all
16		 * other SH variants. If however the branch and the
17		 * delay slot straddle an 8 byte boundary, this increases
18		 * to 3 cycles.
19		 * This align directive ensures this doesn't occur.
20		 */
21		".balign 8\n\t"
22
23		"tst	%0, %0\n\t"
24		"1:\t"
25		"bf/s	1b\n\t"
26		" dt	%0"
27		: "=r" (loops)
28		: "0" (loops)
29		: "t");
30}
31
32inline void __const_udelay(unsigned long xloops)
33{
34	xloops *= 4;
35	__asm__("dmulu.l	%0, %2\n\t"
36		"sts	mach, %0"
37		: "=r" (xloops)
38		: "0" (xloops),
39		  "r" (cpu_data[raw_smp_processor_id()].loops_per_jiffy * (HZ/4))
40		: "macl", "mach");
41	__delay(++xloops);
42}
43
44void __udelay(unsigned long usecs)
45{
46	__const_udelay(usecs * 0x000010c6);  /* 2**32 / 1000000 */
47}
48
49void __ndelay(unsigned long nsecs)
50{
51	__const_udelay(nsecs * 0x00000005);
52}
53
54