delay_64.h 852 字节
Newer Older
L
Linus Torvalds 已提交
1 2 3 4 5 6 7 8 9
#ifndef _X8664_DELAY_H
#define _X8664_DELAY_H

/*
 * Copyright (C) 1993 Linus Torvalds
 *
 * Delay routines calling functions in arch/x86_64/lib/delay.c
 */
 
10
/* Undefined functions to get compile-time errors */
L
Linus Torvalds 已提交
11 12 13 14
extern void __bad_udelay(void);
extern void __bad_ndelay(void);

extern void __udelay(unsigned long usecs);
15
extern void __ndelay(unsigned long nsecs);
L
Linus Torvalds 已提交
16 17 18
extern void __const_udelay(unsigned long usecs);
extern void __delay(unsigned long loops);

19
/* 0x10c7 is 2**32 / 1000000 (rounded up) */
L
Linus Torvalds 已提交
20
#define udelay(n) (__builtin_constant_p(n) ? \
21
	((n) > 20000 ? __bad_udelay() : __const_udelay((n) * 0x10c7ul)) : \
L
Linus Torvalds 已提交
22 23
	__udelay(n))

24
/* 0x5 is 2**32 / 1000000000 (rounded up) */
L
Linus Torvalds 已提交
25 26 27 28 29 30
#define ndelay(n) (__builtin_constant_p(n) ? \
       ((n) > 20000 ? __bad_ndelay() : __const_udelay((n) * 5ul)) : \
       __ndelay(n))


#endif /* defined(_X8664_DELAY_H) */