[deliverable/linux.git] / include / linux / timekeeper_internal.h

/*
 * You SHOULD NOT be including this unless you're vsyscall
 * handling code or timekeeping internal code!
 */

#ifndef _LINUX_TIMEKEEPER_INTERNAL_H
#define _LINUX_TIMEKEEPER_INTERNAL_H

#include <linux/clocksource.h>
#include <linux/jiffies.h>
#include <linux/time.h>

/*
 * Structure holding internal timekeeping values.
 *
 * Note: wall_to_monotonic is what we need to add to xtime (or xtime
 * corrected for sub jiffie times) to get to monotonic time.
 * Monotonic is pegged at zero at system boot time, so
 * wall_to_monotonic will be negative, however, we will ALWAYS keep
 * the tv_nsec part positive so we can use the usual normalization.
 *
 * wall_to_monotonic is moved after resume from suspend for the
 * monotonic time not to jump. To calculate the real boot time offset
 * we need to do offs_real - offs_boot.
 *
 * - wall_to_monotonic is no longer the boot time, getboottime must be
 * used instead.
 */
struct timekeeper {
	/* Current clocksource used for timekeeping. */
	struct clocksource	*clock;
	/* Read function of @clock */
	cycle_t			(*read)(struct clocksource *cs);
	/* Bitmask for two's complement subtraction of non 64bit counters */
	cycle_t			mask;
	/* Last cycle value */
	cycle_t			cycle_last;
	/* NTP adjusted clock multiplier */
	u32			mult;
	/* The shift value of the current clocksource. */
	u32			shift;
	/* Clock shifted nano seconds */
	u64			xtime_nsec;

	/* Monotonic base time */
	ktime_t			base_mono;

	/* Current CLOCK_REALTIME time in seconds */
	u64			xtime_sec;
	/* CLOCK_REALTIME to CLOCK_MONOTONIC offset */
	struct timespec64	wall_to_monotonic;

	/* Offset clock monotonic -> clock realtime */
	ktime_t			offs_real;
	/* Offset clock monotonic -> clock boottime */
	ktime_t			offs_boot;
	/* Offset clock monotonic -> clock tai */
	ktime_t			offs_tai;

	/* The current UTC to TAI offset in seconds */
	s32			tai_offset;

	/* Monotonic raw base time */
	ktime_t			base_raw;

	/* The raw monotonic time for the CLOCK_MONOTONIC_RAW posix clock. */
	struct timespec64	raw_time;

	/* Number of clock cycles in one NTP interval. */
	cycle_t			cycle_interval;
	/* Number of clock shifted nano seconds in one NTP interval. */
	u64			xtime_interval;
	/* shifted nano seconds left over when rounding cycle_interval */
	s64			xtime_remainder;
	/* Raw nano seconds accumulated per NTP interval. */
	u32			raw_interval;

	/*
	 * Difference between accumulated time and NTP time in ntp
	 * shifted nano seconds.
	 */
	s64			ntp_error;
	/*
	 * Shift conversion between clock shifted nano seconds and
	 * ntp shifted nano seconds.
	 */
	u32			ntp_error_shift;
};

#ifdef CONFIG_GENERIC_TIME_VSYSCALL

extern void update_vsyscall(struct timekeeper *tk);
extern void update_vsyscall_tz(void);

#elif defined(CONFIG_GENERIC_TIME_VSYSCALL_OLD)

extern void update_vsyscall_old(struct timespec *ts, struct timespec *wtm,
				struct clocksource *c, u32 mult,
				cycles_t cycle_last);
extern void update_vsyscall_tz(void);

#else

static inline void update_vsyscall(struct timekeeper *tk)
{
}
static inline void update_vsyscall_tz(void)
{
}
#endif

#endif /* _LINUX_TIMEKEEPER_INTERNAL_H */
Commit	Line	Data
d7b4202e JS	1	/*
	2	* You SHOULD NOT be including this unless you're vsyscall
	3	* handling code or timekeeping internal code!
	4	*/
	5
	6	#ifndef _LINUX_TIMEKEEPER_INTERNAL_H
	7	#define _LINUX_TIMEKEEPER_INTERNAL_H
	8
	9	#include <linux/clocksource.h>
	10	#include <linux/jiffies.h>
	11	#include <linux/time.h>
	12
3fdb14fd TG	13	/*
	14	* Structure holding internal timekeeping values.
	15	*
	16	* Note: wall_to_monotonic is what we need to add to xtime (or xtime
	17	* corrected for sub jiffie times) to get to monotonic time.
	18	* Monotonic is pegged at zero at system boot time, so
	19	* wall_to_monotonic will be negative, however, we will ALWAYS keep
	20	* the tv_nsec part positive so we can use the usual normalization.
	21	*
	22	* wall_to_monotonic is moved after resume from suspend for the
47da70d3 TG	23	* monotonic time not to jump. To calculate the real boot time offset
47da70d3 TG	24	* we need to do offs_real - offs_boot.
3fdb14fd TG	25	*
	26	* - wall_to_monotonic is no longer the boot time, getboottime must be
	27	* used instead.
	28	*/
d7b4202e JS	29	struct timekeeper {
	30	/* Current clocksource used for timekeeping. */
	31	struct clocksource *clock;
6d3aadf3 TG	32	/* Read function of @clock */
	33	cycle_t (read)(struct clocksource cs);
	34	/* Bitmask for two's complement subtraction of non 64bit counters */
	35	cycle_t mask;
4a0e6377 TG	36	/* Last cycle value */
4a0e6377 TG	37	cycle_t cycle_last;
d7b4202e JS	38	/* NTP adjusted clock multiplier */
	39	u32 mult;
	40	/* The shift value of the current clocksource. */
	41	u32 shift;
3fdb14fd TG	42	/* Clock shifted nano seconds */
	43	u64 xtime_nsec;
	44
7c032df5 TG	45	/* Monotonic base time */
	46	ktime_t base_mono;
	47
3fdb14fd TG	48	/* Current CLOCK_REALTIME time in seconds */
	49	u64 xtime_sec;
	50	/* CLOCK_REALTIME to CLOCK_MONOTONIC offset */
	51	struct timespec64 wall_to_monotonic;
	52
	53	/* Offset clock monotonic -> clock realtime */
	54	ktime_t offs_real;
	55	/* Offset clock monotonic -> clock boottime */
	56	ktime_t offs_boot;
	57	/* Offset clock monotonic -> clock tai */
	58	ktime_t offs_tai;
	59
3fdb14fd TG	60	/* The current UTC to TAI offset in seconds */
	61	s32 tai_offset;
	62
f519b1a2 TG	63	/* Monotonic raw base time */
	64	ktime_t base_raw;
	65
3fdb14fd TG	66	/* The raw monotonic time for the CLOCK_MONOTONIC_RAW posix clock. */
	67	struct timespec64 raw_time;
	68
d7b4202e JS	69	/* Number of clock cycles in one NTP interval. */
	70	cycle_t cycle_interval;
	71	/* Number of clock shifted nano seconds in one NTP interval. */
	72	u64 xtime_interval;
	73	/* shifted nano seconds left over when rounding cycle_interval */
	74	s64 xtime_remainder;
	75	/* Raw nano seconds accumulated per NTP interval. */
	76	u32 raw_interval;
	77
3fdb14fd TG	78	/*
	79	* Difference between accumulated time and NTP time in ntp
	80	* shifted nano seconds.
	81	*/
d7b4202e	82	s64 ntp_error;
d7b4202e	83	/*
3fdb14fd TG	84	* Shift conversion between clock shifted nano seconds and
3fdb14fd TG	85	* ntp shifted nano seconds.
d7b4202e	86	*/
3fdb14fd	87	u32 ntp_error_shift;
d7b4202e	88	};
189374ae	89
576094b7 JS	90	#ifdef CONFIG_GENERIC_TIME_VSYSCALL
	91
	92	extern void update_vsyscall(struct timekeeper *tk);
	93	extern void update_vsyscall_tz(void);
189374ae	94
576094b7 JS	95	#elif defined(CONFIG_GENERIC_TIME_VSYSCALL_OLD)
	96
	97	extern void update_vsyscall_old(struct timespec ts, struct timespec wtm,
4a0e6377 TG	98	struct clocksource *c, u32 mult,
4a0e6377 TG	99	cycles_t cycle_last);
189374ae	100	extern void update_vsyscall_tz(void);
576094b7	101
189374ae	102	#else
576094b7 JS	103
576094b7 JS	104	static inline void update_vsyscall(struct timekeeper *tk)
189374ae JS	105	{
	106	}
	107	static inline void update_vsyscall_tz(void)
	108	{
	109	}
	110	#endif
	111
d7b4202e	112	#endif /* _LINUX_TIMEKEEPER_INTERNAL_H */