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#ifndef _PPC_DELAY_H
#define _PPC_DELAY_H
/*
* Copyright 1996, Paul Mackerras.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
extern unsigned long loops_per_sec;
extern __inline__ void __delay(unsigned int loops)
{
if (loops != 0)
__asm__ __volatile__("mtctr %0; 1: bdnz 1b" : :
"r" (loops) : "ctr");
}
extern __inline__ void udelay(unsigned long usecs)
{
unsigned long loops;
/* compute (usecs * 2^32 / 10^6) * loops_per_sec / 2^32 */
usecs *= 0x10c6; /* 2^32 / 10^6 */
__asm__("mulhwu %0,%1,%2" : "=r" (loops) :
"r" (usecs), "r" (loops_per_sec));
__delay(loops);
}
#endif /* defined(_PPC_DELAY_H) */
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