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#ifndef _M68K_DELAY_H
#define _M68K_DELAY_H
/*
* Copyright (C) 1994 Hamish Macdonald
*
* Delay routines, using a pre-computed "loops_per_second" value.
*/
extern __inline__ void __delay(unsigned long loops)
{
__asm__ __volatile__ ("1: subql #1,%0; jcc 1b"
: "=d" (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 __inline__ void udelay(unsigned long usecs)
{
unsigned long tmp;
usecs *= 4295; /* 2**32 / 1000000 */
__asm__ ("mulul %2,%0:%1"
: "=d" (usecs), "=d" (tmp)
: "d" (usecs), "1" (loops_per_sec));
__delay(usecs);
}
extern __inline__ unsigned long muldiv(unsigned long a, unsigned long b, unsigned long c)
{
unsigned long tmp;
__asm__ ("mulul %2,%0:%1; divul %3,%0:%1"
: "=d" (tmp), "=d" (a)
: "d" (b), "d" (c), "1" (a));
return a;
}
#endif /* defined(_M68K_DELAY_H) */
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