/***************************************************************************** *                                                                           * * Copyright (c) David L. Mills 1993                                         * *                                                                           * * Permission to use, copy, modify, and distribute this software and its     * * documentation for any purpose and without fee is hereby granted, provided * * that the above copyright notice appears in all copies and that both the   * * copyright notice and this permission notice appear in supporting          * * documentation, and that the name University of Delaware not be used in    * * advertising or publicity pertaining to distribution of the software       * * without specific, written prior permission.  The University of Delaware   * * makes no representations about the suitability this software for any      * * purpose.  It is provided "as is" without express or implied warranty.     * *                                                                           * *****************************************************************************//* * Modification history timex.h *  * 17 Sep 93    David L. Mills *      Created file $NTP/include/sys/timex.h * 07 Oct 93    Torsten Duwe *      Derived linux/timex.h */#ifndef _LINUX_TIMEX_H#define _LINUX_TIMEX_H/* * The following defines establish the engineering parameters of the PLL * model. The HZ variable establishes the timer interrupt frequency, 100 Hz  * for the SunOS kernel, 256 Hz for the Ultrix kernel and 1024 Hz for the * OSF/1 kernel. The SHIFT_HZ define expresses the same value as the * nearest power of two in order to avoid hardware multiply operations. */#define SHIFT_HZ 7		/* log2(HZ) *//* * The SHIFT_KG and SHIFT_KF defines establish the damping of the PLL * and are chosen by analysis for a slightly underdamped convergence * characteristic. The MAXTC define establishes the maximum time constant * of the PLL. With the parameters given and the default time constant of * zero, the PLL will converge in about 15 minutes. */#define SHIFT_KG 8		/* shift for phase increment */#define SHIFT_KF 20		/* shift for frequency increment */#define MAXTC 6			/* maximum time constant (shift) *//* * The SHIFT_SCALE define establishes the decimal point of the time_phase * variable which serves as a an extension to the low-order bits of the * system clock variable. The SHIFT_UPDATE define establishes the decimal * point of the time_offset variable which represents the current offset * with respect to standard time. The FINEUSEC define represents 1 usec in * scaled units. */#define SHIFT_SCALE 24		/* shift for phase scale factor */#define SHIFT_UPDATE (SHIFT_KG + MAXTC) /* shift for offset scale factor */#define FINEUSEC (1 << SHIFT_SCALE) /* 1 us in scaled units */#define MAXPHASE 128000         /* max phase error (us) */#define MAXFREQ 100             /* max frequency error (ppm) */#define MINSEC 16               /* min interval between updates (s) */#define MAXSEC 1200             /* max interval between updates (s) */#define CLOCK_TICK_RATE	1193180 /* Underlying HZ */#define CLOCK_TICK_FACTOR	20	/* Factor of both 1000000 and CLOCK_TICK_RATE */#define LATCH  ((CLOCK_TICK_RATE + HZ/2) / HZ)	/* For divider */#define FINETUNE (((((LATCH * HZ - CLOCK_TICK_RATE) << SHIFT_HZ) * \	(1000000/CLOCK_TICK_FACTOR) / (CLOCK_TICK_RATE/CLOCK_TICK_FACTOR)) \		<< (SHIFT_SCALE-SHIFT_HZ)) / HZ)/* * syscall interface - used (mainly by NTP daemon) * to discipline kernel clock oscillator */struct timex {	int mode;		/* mode selector */	long offset;		/* time offset (usec) */	long frequency;		/* frequency offset (scaled ppm) */	long maxerror;		/* maximum error (usec) */	long esterror;		/* estimated error (usec) */	int status;		/* clock command/status */	long time_constant;	/* pll time constant */	long precision;		/* clock precision (usec) (read only) */	long tolerance;		/* clock frequency tolerance (ppm)				 * (read only)				 */	struct timeval time;	/* (read only) */	long tick;		/* (modified) usecs between clock ticks */};/* * Mode codes (timex.mode)  */#define ADJ_OFFSET		0x0001	/* time offset */#define ADJ_FREQUENCY		0x0002	/* frequency offset */#define ADJ_MAXERROR		0x0004	/* maximum time error */#define ADJ_ESTERROR		0x0008	/* estimated time error */#define ADJ_STATUS		0x0010	/* clock status */#define ADJ_TIMECONST		0x0020	/* pll time constant */#define ADJ_TICK		0x4000	/* tick value */#define ADJ_OFFSET_SINGLESHOT	0x8001	/* old-fashioned adjtime *//* * Clock command/status codes (timex.status) */#define TIME_OK		0	/* clock synchronized */#define TIME_INS	1	/* insert leap second */#define TIME_DEL	2	/* delete leap second */#define TIME_OOP	3	/* leap second in progress */#define TIME_BAD	4	/* clock not synchronized */#ifdef __KERNEL__/* * kernel variables */extern long tick;                      /* timer interrupt period */extern int tickadj;			/* amount of adjustment per tick */extern volatile struct timeval xtime;		/* The current time *//* * phase-lock loop variables */extern int time_status;		/* clock synchronization status */extern long time_offset;	/* time adjustment (us) */extern long time_constant;	/* pll time constant */extern long time_tolerance;	/* frequency tolerance (ppm) */extern long time_precision;	/* clock precision (us) */extern long time_maxerror;	/* maximum error */extern long time_esterror;	/* estimated error */extern long time_phase;		/* phase offset (scaled us) */extern long time_freq;		/* frequency offset (scaled ppm) */extern long time_adj;		/* tick adjust (scaled 1 / HZ) */extern long time_reftime;	/* time at last adjustment (s) */extern long time_adjust;	/* The amount of adjtime left */#endif /* KERNEL */#endif /* LINUX_TIMEX_H */