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-rw-r--r--include/linux/timex.h73
1 files changed, 37 insertions, 36 deletions
diff --git a/include/linux/timex.h b/include/linux/timex.h
index 9007313b5b71..998a55d80acf 100644
--- a/include/linux/timex.h
+++ b/include/linux/timex.h
@@ -53,47 +53,11 @@
53#ifndef _LINUX_TIMEX_H 53#ifndef _LINUX_TIMEX_H
54#define _LINUX_TIMEX_H 54#define _LINUX_TIMEX_H
55 55
56#include <linux/compiler.h>
57#include <linux/time.h> 56#include <linux/time.h>
58 57
59#include <asm/param.h>
60
61#define NTP_API 4 /* NTP API version */ 58#define NTP_API 4 /* NTP API version */
62 59
63/* 60/*
64 * SHIFT_KG and SHIFT_KF establish the damping of the PLL and are chosen
65 * for a slightly underdamped convergence characteristic. SHIFT_KH
66 * establishes the damping of the FLL and is chosen by wisdom and black
67 * art.
68 *
69 * MAXTC establishes the maximum time constant of the PLL. With the
70 * SHIFT_KG and SHIFT_KF values given and a time constant range from
71 * zero to MAXTC, the PLL will converge in 15 minutes to 16 hours,
72 * respectively.
73 */
74#define SHIFT_PLL 4 /* PLL frequency factor (shift) */
75#define SHIFT_FLL 2 /* FLL frequency factor (shift) */
76#define MAXTC 10 /* maximum time constant (shift) */
77
78/*
79 * SHIFT_USEC defines the scaling (shift) of the time_freq and
80 * time_tolerance variables, which represent the current frequency
81 * offset and maximum frequency tolerance.
82 */
83#define SHIFT_USEC 16 /* frequency offset scale (shift) */
84#define PPM_SCALE (NSEC_PER_USEC << (NTP_SCALE_SHIFT - SHIFT_USEC))
85#define PPM_SCALE_INV_SHIFT 19
86#define PPM_SCALE_INV ((1ll << (PPM_SCALE_INV_SHIFT + NTP_SCALE_SHIFT)) / \
87 PPM_SCALE + 1)
88
89#define MAXPHASE 500000000l /* max phase error (ns) */
90#define MAXFREQ 500000 /* max frequency error (ns/s) */
91#define MAXFREQ_SCALED ((s64)MAXFREQ << NTP_SCALE_SHIFT)
92#define MINSEC 256 /* min interval between updates (s) */
93#define MAXSEC 2048 /* max interval between updates (s) */
94#define NTP_PHASE_LIMIT ((MAXPHASE / NSEC_PER_USEC) << 5) /* beyond max. dispersion */
95
96/*
97 * syscall interface - used (mainly by NTP daemon) 61 * syscall interface - used (mainly by NTP daemon)
98 * to discipline kernel clock oscillator 62 * to discipline kernel clock oscillator
99 */ 63 */
@@ -199,9 +163,46 @@ struct timex {
199#define TIME_BAD TIME_ERROR /* bw compat */ 163#define TIME_BAD TIME_ERROR /* bw compat */
200 164
201#ifdef __KERNEL__ 165#ifdef __KERNEL__
166#include <linux/compiler.h>
167#include <linux/types.h>
168#include <linux/param.h>
169
202#include <asm/timex.h> 170#include <asm/timex.h>
203 171
204/* 172/*
173 * SHIFT_KG and SHIFT_KF establish the damping of the PLL and are chosen
174 * for a slightly underdamped convergence characteristic. SHIFT_KH
175 * establishes the damping of the FLL and is chosen by wisdom and black
176 * art.
177 *
178 * MAXTC establishes the maximum time constant of the PLL. With the
179 * SHIFT_KG and SHIFT_KF values given and a time constant range from
180 * zero to MAXTC, the PLL will converge in 15 minutes to 16 hours,
181 * respectively.
182 */
183#define SHIFT_PLL 4 /* PLL frequency factor (shift) */
184#define SHIFT_FLL 2 /* FLL frequency factor (shift) */
185#define MAXTC 10 /* maximum time constant (shift) */
186
187/*
188 * SHIFT_USEC defines the scaling (shift) of the time_freq and
189 * time_tolerance variables, which represent the current frequency
190 * offset and maximum frequency tolerance.
191 */
192#define SHIFT_USEC 16 /* frequency offset scale (shift) */
193#define PPM_SCALE (NSEC_PER_USEC << (NTP_SCALE_SHIFT - SHIFT_USEC))
194#define PPM_SCALE_INV_SHIFT 19
195#define PPM_SCALE_INV ((1ll << (PPM_SCALE_INV_SHIFT + NTP_SCALE_SHIFT)) / \
196 PPM_SCALE + 1)
197
198#define MAXPHASE 500000000l /* max phase error (ns) */
199#define MAXFREQ 500000 /* max frequency error (ns/s) */
200#define MAXFREQ_SCALED ((s64)MAXFREQ << NTP_SCALE_SHIFT)
201#define MINSEC 256 /* min interval between updates (s) */
202#define MAXSEC 2048 /* max interval between updates (s) */
203#define NTP_PHASE_LIMIT ((MAXPHASE / NSEC_PER_USEC) << 5) /* beyond max. dispersion */
204
205/*
205 * kernel variables 206 * kernel variables
206 * Note: maximum error = NTP synch distance = dispersion + delay / 2; 207 * Note: maximum error = NTP synch distance = dispersion + delay / 2;
207 * estimated error = NTP dispersion. 208 * estimated error = NTP dispersion.