1#ifndef _M68K_DELAY_H
2#define _M68K_DELAY_H
3
4#include <asm/param.h>
5
6/*
7 * Copyright (C) 1994 Hamish Macdonald
8 *
9 * Delay routines, using a pre-computed "loops_per_jiffy" value.
10 */
11
12extern __inline__ void __delay(unsigned long loops)
13{
14	__asm__ __volatile__ ("1: subql #1,%0; jcc 1b"
15		: "=d" (loops) : "0" (loops));
16}
17
18extern void __bad_udelay(void);
19
20/*
21 * Use only for very small delays ( < 1 msec).  Should probably use a
22 * lookup table, really, as the multiplications take much too long with
23 * short delays.  This is a "reasonable" implementation, though (and the
24 * first constant multiplications gets optimized away if the delay is
25 * a constant)
26 */
27static inline void __const_udelay(unsigned long xloops)
28{
29	unsigned long tmp;
30
31	__asm__ ("mulul %2,%0:%1"
32		: "=d" (xloops), "=d" (tmp)
33		: "d" (xloops), "1" (loops_per_jiffy));
34	__delay(xloops * HZ);
35}
36
37static inline void __udelay(unsigned long usecs)
38{
39	__const_udelay(usecs * 4295);	/* 2**32 / 1000000 */
40}
41
42#define udelay(n) (__builtin_constant_p(n) ? \
43	((n) > 20000 ? __bad_udelay() : __const_udelay((n) * 4295)) : \
44	__udelay(n))
45
46extern __inline__ unsigned long muldiv(unsigned long a, unsigned long b, unsigned long c)
47{
48	unsigned long tmp;
49
50	__asm__ ("mulul %2,%0:%1; divul %3,%0:%1"
51		: "=d" (tmp), "=d" (a)
52		: "d" (b), "d" (c), "1" (a));
53	return a;
54}
55
56#endif /* defined(_M68K_DELAY_H) */
57