delay.h
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#ifndef _H8300_DELAY_H
#define _H8300_DELAY_H
#include <asm/param.h>
/*
* Copyright (C) 2002 Yoshinori Sato <ysato@sourceforge.jp>
*
* Delay routines, using a pre-computed "loops_per_second" value.
*/
extern __inline__ void __delay(unsigned long loops)
{
__asm__ __volatile__ ("1:\n\t"
"dec.l #1,%0\n\t"
"bne 1b"
:"=r" (loops):"0"(loops));
}
/*
* Use only for very small delays ( < 1 msec). Should probably use a
* lookup table, really, as the multiplications take much too long with
* short delays. This is a "reasonable" implementation, though (and the
* first constant multiplications gets optimized away if the delay is
* a constant)
*/
extern unsigned long loops_per_jiffy;
extern __inline__ void udelay(unsigned long usecs)
{
usecs *= 4295; /* 2**32 / 1000000 */
usecs /= (loops_per_jiffy*HZ);
if (usecs)
__delay(usecs);
}
#endif /* _H8300_DELAY_H */