/*-
 * Copyright (c) 2014, Bryan Venteicher <bryanv@FreeBSD.org>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * $FreeBSD$
 */

#ifndef X86_PVCLOCK
#define X86_PVCLOCK

#include <sys/types.h>
#include <sys/timetc.h>

struct pvclock_vcpu_time_info {
	uint32_t	version;
	uint32_t	pad0;
	uint64_t	tsc_timestamp;
	uint64_t	system_time;
	uint32_t	tsc_to_system_mul;
	int8_t		tsc_shift;
	uint8_t		flags;
	uint8_t		pad[2];
};

#define PVCLOCK_FLAG_TSC_STABLE		0x01
#define PVCLOCK_FLAG_GUEST_PASUED	0x02

typedef struct pvclock_wall_clock *pvclock_get_wallclock_t(void *arg);

struct pvclock_wall_clock {
	uint32_t	version;
	uint32_t	sec;
	uint32_t	nsec;
};

struct pvclock {
	/* Public; initialized by the caller of 'pvclock_init()': */
	pvclock_get_wallclock_t		*get_wallclock;
	void				*get_wallclock_arg;
	struct pvclock_vcpu_time_info	*timeinfos;
	bool				 stable_flag_supported;

	/* Private; initialized by the 'pvclock' API: */
	struct timecounter		 tc;
};

/*
 * NOTE: 'pvclock_get_timecount()' and 'pvclock_get_wallclock()' are purely
 * transitional; they should be removed after 'dev/xen/timer/timer.c' has been
 * migrated to the 'struct pvclock' API.
 */
void		pvclock_resume(void);
uint64_t	pvclock_tsc_freq(struct pvclock_vcpu_time_info *ti);
uint64_t	pvclock_get_timecount(struct pvclock_vcpu_time_info *ti);
void		pvclock_get_wallclock(struct pvclock_wall_clock *wc,
		    struct timespec *ts);

void		pvclock_init(struct pvclock *pvc, device_t dev,
		    const char *tc_name, int tc_quality, u_int tc_flags);
void		pvclock_gettime(struct pvclock *pvc, struct timespec *ts);
int		pvclock_destroy(struct pvclock *pvc);

#endif