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Tip revision: 606135a3081e045b677cde164a296c51f66c4633 authored by Linus Torvalds on 28 February 2007, 04:59:12 UTC
Linux 2.6.21-rc2
Tip revision: 606135a
delay.h
#ifndef _X8664_DELAY_H
#define _X8664_DELAY_H

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

extern void __udelay(unsigned long usecs);
extern void __ndelay(unsigned long nsecs);
extern void __const_udelay(unsigned long usecs);
extern void __delay(unsigned long loops);

/* 0x10c7 is 2**32 / 1000000 (rounded up) */
#define udelay(n) (__builtin_constant_p(n) ? \
	((n) > 20000 ? __bad_udelay() : __const_udelay((n) * 0x10c7ul)) : \
	__udelay(n))

/* 0x5 is 2**32 / 1000000000 (rounded up) */
#define ndelay(n) (__builtin_constant_p(n) ? \
       ((n) > 20000 ? __bad_ndelay() : __const_udelay((n) * 5ul)) : \
       __ndelay(n))


#endif /* defined(_X8664_DELAY_H) */
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