root/usr/src/uts/i86pc/sys/apic_timer.h
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
 */
/*
 * Copyright (c) 2010, Intel Corporation.
 * All rights reserved.
 *
 * Copyright 2020 Joyent, Inc.
 */

#ifndef _SYS_APIC_TIMER_H
#define _SYS_APIC_TIMER_H

#ifdef  __cplusplus
extern "C" {
#endif

#include <sys/time.h>

#define IA32_DEADLINE_TSC_MSR   0x6E0

/* Timer Vector Table register  */
#define APIC_LOCAL_TIMER        0xc8

/* timer vector table           */
#define AV_PERIODIC     0x20000 /* Set timer mode to periodic */
#define AV_DEADLINE     0x40000 /* Set timer mode to deadline */

#define APIC_TIMER_MODE_ONESHOT         0x0
#define APIC_TIMER_MODE_PERIODIC        0x1
#define APIC_TIMER_MODE_DEADLINE        0x2     /* TSC-Deadline timer mode */

extern int      apic_oneshot;
extern uint_t   apic_nsec_per_intr;
extern uint_t   apic_hertz_count;
extern uint64_t apic_ticks_per_SFnsecs;

/*
 * Use scaled-fixed-point arithmetic to calculate apic ticks.
 * Round when dividing (by adding half of divisor to dividend)
 * for one extra bit of precision.
 */

#define SF      (1ULL<<20)              /* Scaling Factor: scale by 2^20 */
#define APIC_TICKS_TO_NSECS(ticks)      ((((int64_t)(ticks) * SF) + \
                                        apic_ticks_per_SFnsecs / 2) / \
                                        apic_ticks_per_SFnsecs);
#define APIC_NSECS_TO_TICKS(nsecs)      (((int64_t)(nsecs) * \
                                        apic_ticks_per_SFnsecs + (SF/2)) / SF)

extern int      apic_timer_init(int);
extern void     apic_timer_reprogram(hrtime_t);
extern void     apic_timer_enable(void);
extern void     apic_timer_disable(void);

extern hrtime_t apic_timer_stop_count(void);
extern void     apic_timer_restart(hrtime_t);

#ifdef  __cplusplus
}
#endif

#endif  /* _SYS_APIC_TIMER_H */