#define NSEC_PER_SEC  1000000000
//#define CLOCK_TICK_RATE /*100000000 */ 1193180
#define LATCH(CLOCK_TICK_RATE,HZ)  ((CLOCK_TICK_RATE + HZ/2) / HZ)
#define SH_DIV(NOM,DEN,LSH) (	((NOM / DEN) << LSH)			\
			     + (((NOM % DEN) << LSH) + DEN / 2) / DEN)
#define ACTHZ (SH_DIV (CLOCK_TICK_RATE, LATCH(CLOCK_TICK_RATE,HZ), 8))
#define TICK_NSEC (SH_DIV (1000000UL * 1000, ACTHZ, 8))


struct {
	int hz;
	int clocktickrate;
} vals[] = {{100, 1193180}, {200, 1193180}, {250, 1193180}, {500, 1193180}, {1000, 1193180},{0,0}};

void do_it(int hz,int tickrate)
{
	int HZ = hz;
	int CLOCK_TICK_RATE = tickrate;
	int tick_nsec = TICK_NSEC;
	int ticks_per_sec = NSEC_PER_SEC/tick_nsec;
	int sec_size = ticks_per_sec * tick_nsec;
	int one_sec_p;
	int err;

	if (sec_size < NSEC_PER_SEC)
		sec_size += tick_nsec;
	one_sec_p = sec_size;
	err = one_sec_p - NSEC_PER_SEC;
	printf( "%4d\t%8d\t%8d\t%10d\t%8d\n",hz, tickrate, tick_nsec, 
		one_sec_p, err);
}
	
void bail(void)
{
	printf("run as: as [hz [clock_tick_rate]]\n");
	exit(1);
}

main(int argc, char** argv)
{
	int i = 0;
	int phz = 0;
	int pcr = vals[0].clocktickrate;

	if (argc > 1) { 
		phz = atoi(argv[1]);
		if (!phz)
			bail();
	}
	if (argc > 2) {
		pcr = atoi(argv[2]);
		if (!pcr)
			bail();
	}

	printf("HZ  \tTICK RATE\tjiffie(ns)\tsecond(ns)\t error (ppbillion)\n");
	while(vals[i].hz) {
		do_it(vals[i].hz, vals[i].clocktickrate);
		i++;
	}
	if (phz)
		do_it(phz, pcr);
}