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