minix/lib/libsys/arch/earm/tsc_util.c

#include <stdio.h>
#include <time.h>
#include <sys/times.h>
#include <sys/types.h>
#include <minix/u64.h>
#include <minix/config.h>
#include <minix/const.h>
#include <minix/minlib.h>
#include <machine/archtypes.h>

#include "sysutil.h"

#ifndef CONFIG_MAX_CPUS
#define CONFIG_MAX_CPUS 1
#endif

#define MICROHZ		1000000		/* number of micros per second */
#define MICROSPERTICK(h)	(MICROHZ/(h))	/* number of micros per HZ tick */

static u32_t calib_hz = 600000000;

u32_t tsc_64_to_micros(u64_t tsc)
{
	u64_t tmp;

	tmp =  tsc / calib_hz;
	return (u32_t) tmp;
}

u32_t tsc_to_micros(u32_t low, u32_t high)
{
	return tsc_64_to_micros(make64(low, high));
}