105  *              ns = cycles / (freq / ns_per_sec)
106  *              ns = cycles * (ns_per_sec / freq)
107  *              ns = cycles * (10^9 / (cpu_khz * 10^3))
108  *              ns = cycles * (10^6 / cpu_khz)
111  *              ns = cycles * (10^6 * SC / cpu_khz) / SC
112  *              ns = cycles * cyc2ns_scale / SC
128 	unsigned long long ns;  in __cycles_2_ns()  local
132 	ns = data.cyc2ns_offset;  in __cycles_2_ns()
133 	ns += mul_u64_u32_shr(cyc, data.cyc2ns_mul, data.cyc2ns_shift);  in __cycles_2_ns()
135 	return ns;  in __cycles_2_ns()
140 	unsigned long long ns;  in cycles_2_ns()  local
142 	ns = __cycles_2_ns(cyc);  in cycles_2_ns()
144 	return ns;  in cycles_2_ns()
240 		/* return the value in ns */  in native_sched_clock()
560  * a maximum error rate of 500ppm (in practice the
611 			 * never be below 500 ppm.  in quick_pit_calibrate()
618 			 * Iterate until the error is less than 500 ppm  in quick_pit_calibrate()
642 	 * error has shrunk to less than 500 ppm.  in quick_pit_calibrate()
1364 		/* Warn if the deviation exceeds 500 ppm */  in tsc_refine_calibration_work()