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#ifndef __ALPHA_DELAY_H
#define __ALPHA_DELAY_H
extern unsigned long loops_per_sec;
/*
* Copyright (C) 1993 Linus Torvalds
*
* Delay routines, using a pre-computed "loops_per_second" value.
*/
extern __inline__ void __delay(unsigned long loops)
{
__asm__ __volatile__(".align 3\n"
"1:\tsubq %0,1,%0\n\t"
"bge %0,1b": "=r" (loops) : "0" (loops));
}
/*
* 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)
{
usecs *= 0x000010c6f7a0b5edUL; /* 2**64 / 1000000 */
__asm__("umulh %1,%2,%0"
:"=r" (usecs)
:"r" (usecs),"r" (loops_per_sec));
__delay(usecs);
}
#endif /* defined(__ALPHA_DELAY_H) */
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