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			There are zero users of tickadj. So remove it. Signed-off-by: John Stultz <johnstul@us.ibm.com> LKML-Reference: <1268968769-19209-2-git-send-email-johnstul@us.ibm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
		
			
				
	
	
		
			280 lines
		
	
	
		
			10 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			280 lines
		
	
	
		
			10 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*****************************************************************************
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|  *                                                                           *
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|  * Copyright (c) David L. Mills 1993                                         *
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|  *                                                                           *
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|  * Permission to use, copy, modify, and distribute this software and its     *
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|  * documentation for any purpose and without fee is hereby granted, provided *
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|  * that the above copyright notice appears in all copies and that both the   *
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|  * copyright notice and this permission notice appear in supporting          *
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|  * documentation, and that the name University of Delaware not be used in    *
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|  * advertising or publicity pertaining to distribution of the software       *
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|  * without specific, written prior permission.  The University of Delaware   *
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|  * makes no representations about the suitability this software for any      *
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|  * purpose.  It is provided "as is" without express or implied warranty.     *
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|  *                                                                           *
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|  *****************************************************************************/
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| 
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| /*
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|  * Modification history timex.h
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|  *
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|  * 29 Dec 97	Russell King
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|  *	Moved CLOCK_TICK_RATE, CLOCK_TICK_FACTOR and FINETUNE to asm/timex.h
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|  *	for ARM machines
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|  *
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|  *  9 Jan 97    Adrian Sun
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|  *      Shifted LATCH define to allow access to alpha machines.
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|  *
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|  * 26 Sep 94	David L. Mills
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|  *	Added defines for hybrid phase/frequency-lock loop.
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|  *
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|  * 19 Mar 94	David L. Mills
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|  *	Moved defines from kernel routines to header file and added new
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|  *	defines for PPS phase-lock loop.
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|  *
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|  * 20 Feb 94	David L. Mills
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|  *	Revised status codes and structures for external clock and PPS
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|  *	signal discipline.
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|  *
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|  * 28 Nov 93	David L. Mills
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|  *	Adjusted parameters to improve stability and increase poll
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|  *	interval.
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|  *
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|  * 17 Sep 93    David L. Mills
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|  *      Created file $NTP/include/sys/timex.h
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|  * 07 Oct 93    Torsten Duwe
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|  *      Derived linux/timex.h
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|  * 1995-08-13    Torsten Duwe
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|  *      kernel PLL updated to 1994-12-13 specs (rfc-1589)
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|  * 1997-08-30    Ulrich Windl
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|  *      Added new constant NTP_PHASE_LIMIT
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|  * 2004-08-12    Christoph Lameter
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|  *      Reworked time interpolation logic
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|  */
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| #ifndef _LINUX_TIMEX_H
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| #define _LINUX_TIMEX_H
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| 
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| #include <linux/time.h>
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| 
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| #define NTP_API		4	/* NTP API version */
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| 
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| /*
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|  * syscall interface - used (mainly by NTP daemon)
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|  * to discipline kernel clock oscillator
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|  */
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| struct timex {
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| 	unsigned int modes;	/* mode selector */
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| 	long offset;		/* time offset (usec) */
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| 	long freq;		/* frequency offset (scaled ppm) */
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| 	long maxerror;		/* maximum error (usec) */
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| 	long esterror;		/* estimated error (usec) */
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| 	int status;		/* clock command/status */
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| 	long constant;		/* pll time constant */
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| 	long precision;		/* clock precision (usec) (read only) */
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| 	long tolerance;		/* clock frequency tolerance (ppm)
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| 				 * (read only)
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| 				 */
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| 	struct timeval time;	/* (read only) */
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| 	long tick;		/* (modified) usecs between clock ticks */
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| 
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| 	long ppsfreq;           /* pps frequency (scaled ppm) (ro) */
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| 	long jitter;            /* pps jitter (us) (ro) */
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| 	int shift;              /* interval duration (s) (shift) (ro) */
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| 	long stabil;            /* pps stability (scaled ppm) (ro) */
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| 	long jitcnt;            /* jitter limit exceeded (ro) */
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| 	long calcnt;            /* calibration intervals (ro) */
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| 	long errcnt;            /* calibration errors (ro) */
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| 	long stbcnt;            /* stability limit exceeded (ro) */
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| 
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| 	int tai;		/* TAI offset (ro) */
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| 
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| 	int  :32; int  :32; int  :32; int  :32;
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| 	int  :32; int  :32; int  :32; int  :32;
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| 	int  :32; int  :32; int  :32;
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| };
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| 
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| /*
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|  * Mode codes (timex.mode)
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|  */
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| #define ADJ_OFFSET		0x0001	/* time offset */
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| #define ADJ_FREQUENCY		0x0002	/* frequency offset */
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| #define ADJ_MAXERROR		0x0004	/* maximum time error */
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| #define ADJ_ESTERROR		0x0008	/* estimated time error */
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| #define ADJ_STATUS		0x0010	/* clock status */
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| #define ADJ_TIMECONST		0x0020	/* pll time constant */
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| #define ADJ_TAI			0x0080	/* set TAI offset */
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| #define ADJ_MICRO		0x1000	/* select microsecond resolution */
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| #define ADJ_NANO		0x2000	/* select nanosecond resolution */
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| #define ADJ_TICK		0x4000	/* tick value */
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| 
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| #ifdef __KERNEL__
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| #define ADJ_ADJTIME		0x8000	/* switch between adjtime/adjtimex modes */
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| #define ADJ_OFFSET_SINGLESHOT	0x0001	/* old-fashioned adjtime */
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| #define ADJ_OFFSET_READONLY	0x2000	/* read-only adjtime */
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| #else
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| #define ADJ_OFFSET_SINGLESHOT	0x8001	/* old-fashioned adjtime */
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| #define ADJ_OFFSET_SS_READ	0xa001	/* read-only adjtime */
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| #endif
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| 
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| /* NTP userland likes the MOD_ prefix better */
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| #define MOD_OFFSET	ADJ_OFFSET
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| #define MOD_FREQUENCY	ADJ_FREQUENCY
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| #define MOD_MAXERROR	ADJ_MAXERROR
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| #define MOD_ESTERROR	ADJ_ESTERROR
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| #define MOD_STATUS	ADJ_STATUS
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| #define MOD_TIMECONST	ADJ_TIMECONST
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| #define MOD_TAI	ADJ_TAI
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| #define MOD_MICRO	ADJ_MICRO
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| #define MOD_NANO	ADJ_NANO
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| 
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| 
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| /*
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|  * Status codes (timex.status)
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|  */
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| #define STA_PLL		0x0001	/* enable PLL updates (rw) */
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| #define STA_PPSFREQ	0x0002	/* enable PPS freq discipline (rw) */
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| #define STA_PPSTIME	0x0004	/* enable PPS time discipline (rw) */
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| #define STA_FLL		0x0008	/* select frequency-lock mode (rw) */
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| 
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| #define STA_INS		0x0010	/* insert leap (rw) */
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| #define STA_DEL		0x0020	/* delete leap (rw) */
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| #define STA_UNSYNC	0x0040	/* clock unsynchronized (rw) */
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| #define STA_FREQHOLD	0x0080	/* hold frequency (rw) */
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| 
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| #define STA_PPSSIGNAL	0x0100	/* PPS signal present (ro) */
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| #define STA_PPSJITTER	0x0200	/* PPS signal jitter exceeded (ro) */
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| #define STA_PPSWANDER	0x0400	/* PPS signal wander exceeded (ro) */
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| #define STA_PPSERROR	0x0800	/* PPS signal calibration error (ro) */
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| 
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| #define STA_CLOCKERR	0x1000	/* clock hardware fault (ro) */
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| #define STA_NANO	0x2000	/* resolution (0 = us, 1 = ns) (ro) */
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| #define STA_MODE	0x4000	/* mode (0 = PLL, 1 = FLL) (ro) */
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| #define STA_CLK		0x8000	/* clock source (0 = A, 1 = B) (ro) */
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| 
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| /* read-only bits */
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| #define STA_RONLY (STA_PPSSIGNAL | STA_PPSJITTER | STA_PPSWANDER | \
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| 	STA_PPSERROR | STA_CLOCKERR | STA_NANO | STA_MODE | STA_CLK)
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| 
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| /*
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|  * Clock states (time_state)
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|  */
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| #define TIME_OK		0	/* clock synchronized, no leap second */
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| #define TIME_INS	1	/* insert leap second */
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| #define TIME_DEL	2	/* delete leap second */
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| #define TIME_OOP	3	/* leap second in progress */
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| #define TIME_WAIT	4	/* leap second has occurred */
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| #define TIME_ERROR	5	/* clock not synchronized */
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| #define TIME_BAD	TIME_ERROR /* bw compat */
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| 
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| #ifdef __KERNEL__
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| #include <linux/compiler.h>
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| #include <linux/types.h>
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| #include <linux/param.h>
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| 
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| #include <asm/timex.h>
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| 
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| /*
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|  * SHIFT_PLL is used as a dampening factor to define how much we
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|  * adjust the frequency correction for a given offset in PLL mode.
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|  * It also used in dampening the offset correction, to define how
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|  * much of the current value in time_offset we correct for each
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|  * second. Changing this value changes the stiffness of the ntp
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|  * adjustment code. A lower value makes it more flexible, reducing
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|  * NTP convergence time. A higher value makes it stiffer, increasing
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|  * convergence time, but making the clock more stable.
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|  *
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|  * In David Mills' nanokernel reference implementation SHIFT_PLL is 4.
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|  * However this seems to increase convergence time much too long.
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|  *
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|  * https://lists.ntp.org/pipermail/hackers/2008-January/003487.html
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|  *
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|  * In the above mailing list discussion, it seems the value of 4
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|  * was appropriate for other Unix systems with HZ=100, and that
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|  * SHIFT_PLL should be decreased as HZ increases. However, Linux's
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|  * clock steering implementation is HZ independent.
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|  *
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|  * Through experimentation, a SHIFT_PLL value of 2 was found to allow
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|  * for fast convergence (very similar to the NTPv3 code used prior to
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|  * v2.6.19), with good clock stability.
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|  *
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|  *
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|  * SHIFT_FLL is used as a dampening factor to define how much we
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|  * adjust the frequency correction for a given offset in FLL mode.
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|  * In David Mills' nanokernel reference implementation SHIFT_FLL is 2.
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|  *
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|  * MAXTC establishes the maximum time constant of the PLL.
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|  */
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| #define SHIFT_PLL	2	/* PLL frequency factor (shift) */
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| #define SHIFT_FLL	2	/* FLL frequency factor (shift) */
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| #define MAXTC		10	/* maximum time constant (shift) */
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| 
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| /*
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|  * SHIFT_USEC defines the scaling (shift) of the time_freq and
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|  * time_tolerance variables, which represent the current frequency
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|  * offset and maximum frequency tolerance.
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|  */
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| #define SHIFT_USEC 16		/* frequency offset scale (shift) */
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| #define PPM_SCALE ((s64)NSEC_PER_USEC << (NTP_SCALE_SHIFT - SHIFT_USEC))
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| #define PPM_SCALE_INV_SHIFT 19
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| #define PPM_SCALE_INV ((1LL << (PPM_SCALE_INV_SHIFT + NTP_SCALE_SHIFT)) / \
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| 		       PPM_SCALE + 1)
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| 
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| #define MAXPHASE 500000000L	/* max phase error (ns) */
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| #define MAXFREQ 500000		/* max frequency error (ns/s) */
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| #define MAXFREQ_SCALED ((s64)MAXFREQ << NTP_SCALE_SHIFT)
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| #define MINSEC 256		/* min interval between updates (s) */
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| #define MAXSEC 2048		/* max interval between updates (s) */
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| #define NTP_PHASE_LIMIT ((MAXPHASE / NSEC_PER_USEC) << 5) /* beyond max. dispersion */
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| 
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| /*
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|  * kernel variables
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|  * Note: maximum error = NTP synch distance = dispersion + delay / 2;
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|  * estimated error = NTP dispersion.
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|  */
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| extern unsigned long tick_usec;		/* USER_HZ period (usec) */
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| extern unsigned long tick_nsec;		/* ACTHZ          period (nsec) */
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| 
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| /*
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|  * phase-lock loop variables
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|  */
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| extern int time_status;		/* clock synchronization status bits */
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| 
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| extern void ntp_init(void);
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| extern void ntp_clear(void);
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| 
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| /**
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|  * ntp_synced - Returns 1 if the NTP status is not UNSYNC
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|  *
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|  */
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| static inline int ntp_synced(void)
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| {
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| 	return !(time_status & STA_UNSYNC);
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| }
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| 
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| /* Required to safely shift negative values */
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| #define shift_right(x, s) ({	\
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| 	__typeof__(x) __x = (x);	\
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| 	__typeof__(s) __s = (s);	\
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| 	__x < 0 ? -(-__x >> __s) : __x >> __s;	\
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| })
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| 
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| #define NTP_SCALE_SHIFT		32
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| 
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| #define NTP_INTERVAL_FREQ  (HZ)
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| #define NTP_INTERVAL_LENGTH (NSEC_PER_SEC/NTP_INTERVAL_FREQ)
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| 
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| /* Returns how long ticks are at present, in ns / 2^NTP_SCALE_SHIFT. */
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| extern u64 tick_length;
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| 
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| extern void second_overflow(void);
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| extern void update_ntp_one_tick(void);
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| extern int do_adjtimex(struct timex *);
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| 
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| int read_current_timer(unsigned long *timer_val);
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| 
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| /* The clock frequency of the i8253/i8254 PIT */
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| #define PIT_TICK_RATE 1193182ul
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| 
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| #endif /* KERNEL */
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| 
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| #endif /* LINUX_TIMEX_H */
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