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1 #ifndef _H8300_DELAY_H
2 #define _H8300_DELAY_H
3 
4 #include <asm/param.h>
5 
6 /*
7  * Copyright (C) 2002 Yoshinori Sato <ysato@sourceforge.jp>
8  *
9  * Delay routines, using a pre-computed "loops_per_second" value.
10  */
11 
__delay(unsigned long loops)12 static inline void __delay(unsigned long loops)
13 {
14 	__asm__ __volatile__ ("1:\n\t"
15 			      "dec.l #1,%0\n\t"
16 			      "bne 1b"
17 			      :"=r" (loops):"0"(loops));
18 }
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  */
27 
28 extern unsigned long loops_per_jiffy;
29 
udelay(unsigned long usecs)30 static inline void udelay(unsigned long usecs)
31 {
32 	usecs *= 4295;		/* 2**32 / 1000000 */
33 	usecs /= (loops_per_jiffy*HZ);
34 	if (usecs)
35 		__delay(usecs);
36 }
37 
38 #endif /* _H8300_DELAY_H */
39