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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(int loops)
{
__asm__("\n\tmovel %0,d0\n1:\tsubql #1,d0\n\tbpls 1b\n"
: /* no outputs */
: "g" (loops)
: "d0");
}
/*
* division by multiplication: you don't have to worry about
* loss of precision.
*
* 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)
{
asm ("mulul %1,d0,%0\n\t"
"divul %2,d0,%0"
: "=d" (usecs)
: "d" (usecs),
"i" (1000000),
"0" (loops_per_sec)
: "d0");
__delay(usecs);
}
#endif /* defined(_M68K_DELAY_H) */
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