root/include/asm-parisc/delay.h

INCLUDED FROM

DEFINITIONS

1. __delay
2. __cr16_delay
3. __udelay

#ifndef _PARISC_DELAY_H
#define _PARISC_DELAY_H

#include <asm/system.h>    /* for mfctl() */
#include <asm/processor.h> /* for boot_cpu_data */


/*
 * Copyright (C) 1993 Linus Torvalds
 *
 * Delay routines
 */

static __inline__ void __delay(unsigned long loops) {
        asm volatile(
        "       .balignl        64,0x34000034\n"
        "       addib,UV -1,%0,.\n"
        "       nop\n"
                : "=r" (loops) : "0" (loops));
}

static __inline__ void __cr16_delay(unsigned long clocks) {
        unsigned long start;

        /*
         * Note: Due to unsigned math, cr16 rollovers shouldn't be
         * a problem here. However, on 32 bit, we need to make sure
         * we don't pass in too big a value. The current default
         * value of MAX_UDELAY_MS should help prevent this.
         */

        start = mfctl(16);
        while ((mfctl(16) - start) < clocks)
            ;
}

static __inline__ void __udelay(unsigned long usecs) {
        __cr16_delay(usecs * ((unsigned long)boot_cpu_data.cpu_hz / 1000000UL));
}

#define udelay(n) __udelay(n)

#endif /* defined(_PARISC_DELAY_H) */