delay.h

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#ifndef _PARISC_DELAY_H
#define _PARISC_DELAY_H

#include <asm/special_insns.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) */