1/*
2 * Copyright (c) 2000-2007 Apple Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28/*
29 * @OSF_COPYRIGHT@
30 */
31/*
32 * Mach Operating System
33 * Copyright (c) 1991,1990,1989,1988,1987 Carnegie Mellon University
34 * All Rights Reserved.
35 *
36 * Permission to use, copy, modify and distribute this software and its
37 * documentation is hereby granted, provided that both the copyright
38 * notice and this permission notice appear in all copies of the
39 * software, derivative works or modified versions, and any portions
40 * thereof, and that both notices appear in supporting documentation.
41 *
42 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
43 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
44 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
45 *
46 * Carnegie Mellon requests users of this software to return to
47 *
48 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
49 *  School of Computer Science
50 *  Carnegie Mellon University
51 *  Pittsburgh PA 15213-3890
52 *
53 * any improvements or extensions that they make and grant Carnegie Mellon
54 * the rights to redistribute these changes.
55 */
56/*
57 */
58
59#include <machine_timer_routines.h>
60
61#include <mach/kern_return.h>
62#include <mach/port.h>
63#include <kern/queue.h>
64#include <kern/processor.h>
65#include <kern/thread.h>
66#include <kern/sched_prim.h>
67#include <kern/timer.h>
68
69int precise_user_kernel_time = 1;
70
71/*
72 *	timer_init initializes a timer.
73 */
74void
75timer_init(
76	timer_t		timer)
77{
78	timer->tstamp = 0;
79#if	defined(__LP64__)
80	timer->all_bits = 0;
81#else
82	timer->low_bits = 0;
83	timer->high_bits = 0;
84	timer->high_bits_check = 0;
85#endif	/* defined(__LP64__) */
86}
87
88/*
89 *	Calculate the difference between a timer
90 *	and saved value, and update the saved value.
91 */
92uint64_t
93timer_delta(
94	timer_t		timer,
95	uint64_t	*save)
96{
97	uint64_t	new, old = *save;
98
99	*save = new = timer_grab(timer);
100
101	return (new - old);
102}
103
104void
105timer_advance(
106	timer_t		timer,
107	uint64_t	delta)
108{
109#if	defined(__LP64__)
110	timer->all_bits += delta;
111#else
112	uint64_t	low;
113
114	low = delta + timer->low_bits;
115	if (low >> 32)
116		timer_update(timer, (uint32_t)(timer->high_bits + (low >> 32)), (uint32_t)low);
117	else
118		timer->low_bits = (uint32_t)low;
119#endif 	/* defined(__LP64__) */
120}
121
122void
123timer_start(
124	timer_t		timer,
125	uint64_t	tstamp)
126{
127	timer->tstamp = tstamp;
128}
129
130void
131timer_stop(
132	timer_t		timer,
133	uint64_t	tstamp)
134{
135	timer_advance(timer, tstamp - timer->tstamp);
136}
137
138/*
139 *	Update the timer and start a new one.
140 */
141void
142timer_switch(
143	timer_t			timer,
144	uint64_t		tstamp,
145	timer_t			new_timer)
146{
147	timer_advance(timer, tstamp - timer->tstamp);
148	new_timer->tstamp = tstamp;
149}
150
151#if	MACHINE_TIMER_ROUTINES
152
153/*
154 *	Machine-dependent code implements the timer event routine.
155 */
156
157#else	/* MACHINE_TIMER_ROUTINES */
158
159/*
160 *	Update the current thread timer and
161 *	start the new timer.  Requires a current
162 *	and new timer.
163 *
164 *	Called with interrupts disabled.
165 */
166void
167thread_timer_event(
168	uint64_t		tstamp,
169	timer_t			new_timer)
170{
171	processor_t		processor = current_processor();
172	timer_t			timer;
173
174	/*
175	 *	Update current timer.
176	 */
177	timer = PROCESSOR_DATA(processor, thread_timer);
178	timer_advance(timer, tstamp - timer->tstamp);
179
180	/*
181	 *	Start new timer.
182	 */
183	PROCESSOR_DATA(processor, thread_timer) = new_timer;
184	new_timer->tstamp = tstamp;
185}
186
187#endif	/* MACHINE_TIMER_ROUTINES */
188