1 files changed, 360 insertions, 0 deletions
diff --git a/include/linux/timekeeping.h b/include/linux/timekeeping.h
new file mode 100644
index 000000000000..aee2c1a46e47
--- /dev/null
+++ b/include/linux/timekeeping.h
@@ -0,0 +1,360 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_TIMEKEEPING_H
+#define _LINUX_TIMEKEEPING_H
+
+#include <linux/errno.h>
+#include <linux/clocksource_ids.h>
+#include <linux/ktime.h>
+
+/* Included from linux/ktime.h */
+
+void timekeeping_init(void);
+extern int timekeeping_suspended;
+
+/* Architecture timer tick functions: */
+extern void legacy_timer_tick(unsigned long ticks);
+
+/*
+ * Get and set timeofday
+ */
+extern int do_settimeofday64(const struct timespec64 *ts);
+extern int do_sys_settimeofday64(const struct timespec64 *tv,
+				 const struct timezone *tz);
+
+/*
+ * ktime_get() family - read the current time in a multitude of ways.
+ *
+ * The default time reference is CLOCK_MONOTONIC, starting at
+ * boot time but not counting the time spent in suspend.
+ * For other references, use the functions with "real", "clocktai",
+ * "boottime" and "raw" suffixes.
+ *
+ * To get the time in a different format, use the ones with
+ * "ns", "ts64" and "seconds" suffix.
+ *
+ * See Documentation/core-api/timekeeping.rst for more details.
+ */
+
+
+/*
+ * timespec64 based interfaces
+ */
+extern void ktime_get_raw_ts64(struct timespec64 *ts);
+extern void ktime_get_ts64(struct timespec64 *ts);
+extern void ktime_get_real_ts64(struct timespec64 *tv);
+extern void ktime_get_coarse_ts64(struct timespec64 *ts);
+extern void ktime_get_coarse_real_ts64(struct timespec64 *ts);
+extern void ktime_get_clock_ts64(clockid_t id, struct timespec64 *ts);
+
+/* Multigrain timestamp interfaces */
+extern void ktime_get_coarse_real_ts64_mg(struct timespec64 *ts);
+extern void ktime_get_real_ts64_mg(struct timespec64 *ts);
+extern unsigned long timekeeping_get_mg_floor_swaps(void);
+
+void getboottime64(struct timespec64 *ts);
+
+/*
+ * time64_t base interfaces
+ */
+extern time64_t ktime_get_seconds(void);
+extern time64_t __ktime_get_real_seconds(void);
+extern time64_t ktime_get_real_seconds(void);
+
+/*
+ * ktime_t based interfaces
+ */
+
+enum tk_offsets {
+	TK_OFFS_REAL,
+	TK_OFFS_BOOT,
+	TK_OFFS_TAI,
+	TK_OFFS_MAX,
+};
+
+extern ktime_t ktime_get(void);
+extern ktime_t ktime_get_with_offset(enum tk_offsets offs);
+extern ktime_t ktime_get_coarse_with_offset(enum tk_offsets offs);
+extern ktime_t ktime_mono_to_any(ktime_t tmono, enum tk_offsets offs);
+extern ktime_t ktime_get_raw(void);
+extern u32 ktime_get_resolution_ns(void);
+
+/**
+ * ktime_get_real - get the real (wall-) time in ktime_t format
+ *
+ * Returns: real (wall) time in ktime_t format
+ */
+static inline ktime_t ktime_get_real(void)
+{
+	return ktime_get_with_offset(TK_OFFS_REAL);
+}
+
+static inline ktime_t ktime_get_coarse_real(void)
+{
+	return ktime_get_coarse_with_offset(TK_OFFS_REAL);
+}
+
+/**
+ * ktime_get_boottime - Get monotonic time since boot in ktime_t format
+ *
+ * This is similar to CLOCK_MONTONIC/ktime_get, but also includes the
+ * time spent in suspend.
+ *
+ * Returns: monotonic time since boot in ktime_t format
+ */
+static inline ktime_t ktime_get_boottime(void)
+{
+	return ktime_get_with_offset(TK_OFFS_BOOT);
+}
+
+static inline ktime_t ktime_get_coarse_boottime(void)
+{
+	return ktime_get_coarse_with_offset(TK_OFFS_BOOT);
+}
+
+/**
+ * ktime_get_clocktai - Get the TAI time of day in ktime_t format
+ *
+ * Returns: the TAI time of day in ktime_t format
+ */
+static inline ktime_t ktime_get_clocktai(void)
+{
+	return ktime_get_with_offset(TK_OFFS_TAI);
+}
+
+static inline ktime_t ktime_get_coarse_clocktai(void)
+{
+	return ktime_get_coarse_with_offset(TK_OFFS_TAI);
+}
+
+static inline ktime_t ktime_get_coarse(void)
+{
+	struct timespec64 ts;
+
+	ktime_get_coarse_ts64(&ts);
+	return timespec64_to_ktime(ts);
+}
+
+static inline u64 ktime_get_coarse_ns(void)
+{
+	return ktime_to_ns(ktime_get_coarse());
+}
+
+static inline u64 ktime_get_coarse_real_ns(void)
+{
+	return ktime_to_ns(ktime_get_coarse_real());
+}
+
+static inline u64 ktime_get_coarse_boottime_ns(void)
+{
+	return ktime_to_ns(ktime_get_coarse_boottime());
+}
+
+static inline u64 ktime_get_coarse_clocktai_ns(void)
+{
+	return ktime_to_ns(ktime_get_coarse_clocktai());
+}
+
+/**
+ * ktime_mono_to_real - Convert monotonic time to clock realtime
+ * @mono: monotonic time to convert
+ *
+ * Returns: time converted to realtime clock
+ */
+static inline ktime_t ktime_mono_to_real(ktime_t mono)
+{
+	return ktime_mono_to_any(mono, TK_OFFS_REAL);
+}
+
+/**
+ * ktime_get_ns - Get the current time in nanoseconds
+ *
+ * Returns: current time converted to nanoseconds
+ */
+static inline u64 ktime_get_ns(void)
+{
+	return ktime_to_ns(ktime_get());
+}
+
+/**
+ * ktime_get_real_ns - Get the current real/wall time in nanoseconds
+ *
+ * Returns: current real time converted to nanoseconds
+ */
+static inline u64 ktime_get_real_ns(void)
+{
+	return ktime_to_ns(ktime_get_real());
+}
+
+/**
+ * ktime_get_boottime_ns - Get the monotonic time since boot in nanoseconds
+ *
+ * Returns: current boottime converted to nanoseconds
+ */
+static inline u64 ktime_get_boottime_ns(void)
+{
+	return ktime_to_ns(ktime_get_boottime());
+}
+
+/**
+ * ktime_get_clocktai_ns - Get the current TAI time of day in nanoseconds
+ *
+ * Returns: current TAI time converted to nanoseconds
+ */
+static inline u64 ktime_get_clocktai_ns(void)
+{
+	return ktime_to_ns(ktime_get_clocktai());
+}
+
+/**
+ * ktime_get_raw_ns - Get the raw monotonic time in nanoseconds
+ *
+ * Returns: current raw monotonic time converted to nanoseconds
+ */
+static inline u64 ktime_get_raw_ns(void)
+{
+	return ktime_to_ns(ktime_get_raw());
+}
+
+extern u64 ktime_get_mono_fast_ns(void);
+extern u64 ktime_get_raw_fast_ns(void);
+extern u64 ktime_get_boot_fast_ns(void);
+extern u64 ktime_get_tai_fast_ns(void);
+extern u64 ktime_get_real_fast_ns(void);
+
+/*
+ * timespec64/time64_t interfaces utilizing the ktime based ones
+ * for API completeness, these could be implemented more efficiently
+ * if needed.
+ */
+static inline void ktime_get_boottime_ts64(struct timespec64 *ts)
+{
+	*ts = ktime_to_timespec64(ktime_get_boottime());
+}
+
+static inline void ktime_get_coarse_boottime_ts64(struct timespec64 *ts)
+{
+	*ts = ktime_to_timespec64(ktime_get_coarse_boottime());
+}
+
+static inline time64_t ktime_get_boottime_seconds(void)
+{
+	return ktime_divns(ktime_get_coarse_boottime(), NSEC_PER_SEC);
+}
+
+static inline void ktime_get_clocktai_ts64(struct timespec64 *ts)
+{
+	*ts = ktime_to_timespec64(ktime_get_clocktai());
+}
+
+static inline void ktime_get_coarse_clocktai_ts64(struct timespec64 *ts)
+{
+	*ts = ktime_to_timespec64(ktime_get_coarse_clocktai());
+}
+
+static inline time64_t ktime_get_clocktai_seconds(void)
+{
+	return ktime_divns(ktime_get_coarse_clocktai(), NSEC_PER_SEC);
+}
+
+/*
+ * RTC specific
+ */
+extern bool timekeeping_rtc_skipsuspend(void);
+extern bool timekeeping_rtc_skipresume(void);
+
+extern void timekeeping_inject_sleeptime64(const struct timespec64 *delta);
+
+/*
+ * Auxiliary clock interfaces
+ */
+#ifdef CONFIG_POSIX_AUX_CLOCKS
+extern bool ktime_get_aux(clockid_t id, ktime_t *kt);
+extern bool ktime_get_aux_ts64(clockid_t id, struct timespec64 *kt);
+#else
+static inline bool ktime_get_aux(clockid_t id, ktime_t *kt) { return false; }
+static inline bool ktime_get_aux_ts64(clockid_t id, struct timespec64 *kt) { return false; }
+#endif
+
+/**
+ * struct system_time_snapshot - simultaneous raw/real time capture with
+ *				 counter value
+ * @cycles:	Clocksource counter value to produce the system times
+ * @real:	Realtime system time
+ * @boot:	Boot time
+ * @raw:	Monotonic raw system time
+ * @cs_id:	Clocksource ID
+ * @clock_was_set_seq:	The sequence number of clock-was-set events
+ * @cs_was_changed_seq:	The sequence number of clocksource change events
+ */
+struct system_time_snapshot {
+	u64			cycles;
+	ktime_t			real;
+	ktime_t			boot;
+	ktime_t			raw;
+	enum clocksource_ids	cs_id;
+	unsigned int		clock_was_set_seq;
+	u8			cs_was_changed_seq;
+};
+
+/**
+ * struct system_device_crosststamp - system/device cross-timestamp
+ *				      (synchronized capture)
+ * @device:		Device time
+ * @sys_realtime:	Realtime simultaneous with device time
+ * @sys_monoraw:	Monotonic raw simultaneous with device time
+ */
+struct system_device_crosststamp {
+	ktime_t device;
+	ktime_t sys_realtime;
+	ktime_t sys_monoraw;
+};
+
+/**
+ * struct system_counterval_t - system counter value with the ID of the
+ *				corresponding clocksource
+ * @cycles:	System counter value
+ * @cs_id:	Clocksource ID corresponding to system counter value. Used by
+ *		timekeeping code to verify comparability of two cycle values.
+ *		The default ID, CSID_GENERIC, does not identify a specific
+ *		clocksource.
+ * @use_nsecs:	@cycles is in nanoseconds.
+ */
+struct system_counterval_t {
+	u64			cycles;
+	enum clocksource_ids	cs_id;
+	bool			use_nsecs;
+};
+
+extern bool ktime_real_to_base_clock(ktime_t treal,
+				     enum clocksource_ids base_id, u64 *cycles);
+extern bool timekeeping_clocksource_has_base(enum clocksource_ids id);
+
+/*
+ * Get cross timestamp between system clock and device clock
+ */
+extern int get_device_system_crosststamp(
+			int (*get_time_fn)(ktime_t *device_time,
+				struct system_counterval_t *system_counterval,
+				void *ctx),
+			void *ctx,
+			struct system_time_snapshot *history,
+			struct system_device_crosststamp *xtstamp);
+
+/*
+ * Simultaneously snapshot realtime and monotonic raw clocks
+ */
+extern void ktime_get_snapshot(struct system_time_snapshot *systime_snapshot);
+
+/*
+ * Persistent clock related interfaces
+ */
+extern int persistent_clock_is_local;
+
+extern void read_persistent_clock64(struct timespec64 *ts);
+void read_persistent_wall_and_boot_offset(struct timespec64 *wall_clock,
+					  struct timespec64 *boot_offset);
+#ifdef CONFIG_GENERIC_CMOS_UPDATE
+extern int update_persistent_clock64(struct timespec64 now);
+#endif
+
+#endif