1/*
2 * Copyright (c) 2000-2008 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 * @APPLE_FREE_COPYRIGHT@
33 */
34/*
35 *	File:		etimer.c
36 *	Purpose:	Routines for handling the machine independent
37 *				event timer.
38 */
39
40#include <mach/mach_types.h>
41
42#include <kern/clock.h>
43#include <kern/thread.h>
44#include <kern/timer_queue.h>
45#include <kern/processor.h>
46#include <kern/macro_help.h>
47#include <kern/spl.h>
48#include <kern/etimer.h>
49#include <kern/pms.h>
50
51#include <machine/commpage.h>
52#include <machine/machine_routines.h>
53
54#include <sys/kdebug.h>
55#include <ppc/exception.h>
56
57/*
58 * 	Event timer interrupt.
59 *
60 * XXX a drawback of this implementation is that events serviced earlier must not set deadlines
61 *     that occur before the entire chain completes.
62 *
63 * XXX a better implementation would use a set of generic callouts and iterate over them
64 */
65void
66etimer_intr(
67__unused int inuser,
68__unused uint64_t iaddr)
69{
70	uint64_t		abstime;
71	rtclock_timer_t		*mytimer;
72	struct per_proc_info	*pp;
73
74	pp = getPerProc();
75
76	mytimer = &pp->rtclock_timer;				/* Point to the event timer */
77
78	abstime = mach_absolute_time();				/* Get the time now */
79
80	/* is it time for power management state change? */
81	if (pp->pms.pmsPop <= abstime) {
82	        KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_EXCP_DECI, 3) | DBG_FUNC_START, 0, 0, 0, 0, 0);
83		pmsStep(1);					/* Yes, advance step */
84	        KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_EXCP_DECI, 3) | DBG_FUNC_END, 0, 0, 0, 0, 0);
85
86		abstime = mach_absolute_time();			/* Get the time again since we ran a bit */
87	}
88
89	/* has a pending clock timer expired? */
90	if (mytimer->deadline <= abstime) {			/* Have we expired the deadline? */
91		mytimer->has_expired = TRUE;			/* Remember that we popped */
92		mytimer->deadline = timer_queue_expire(&mytimer->queue, abstime);
93		mytimer->has_expired = FALSE;
94	}
95
96	/* schedule our next deadline */
97	pp->rtcPop = EndOfAllTime;				/* any real deadline will be earlier */
98	etimer_resync_deadlines();
99}
100
101/*
102 * Set the clock deadline.
103 */
104void etimer_set_deadline(uint64_t deadline)
105{
106	rtclock_timer_t		*mytimer;
107	spl_t			s;
108	struct per_proc_info	*pp;
109
110	s = splclock();					/* no interruptions */
111	pp = getPerProc();
112
113	mytimer = &pp->rtclock_timer;			/* Point to the timer itself */
114	mytimer->deadline = deadline;			/* Set the new expiration time */
115
116	etimer_resync_deadlines();
117
118	splx(s);
119}
120
121
122/*
123 * Re-evaluate the outstanding deadlines and select the most proximate.
124 *
125 * Should be called at splclock.
126 */
127void
128etimer_resync_deadlines(void)
129{
130	uint64_t		deadline;
131	rtclock_timer_t		*mytimer;
132	spl_t			s = splclock();		/* No interruptions please */
133	struct per_proc_info	*pp;
134
135	pp = getPerProc();
136
137	deadline = ~0ULL;
138
139	/* if we have a clock timer set sooner, pop on that */
140	mytimer = &pp->rtclock_timer;			/* Point to the timer itself */
141	if (!mytimer->has_expired && mytimer->deadline > 0)
142		deadline = mytimer->deadline;
143
144	/* if we have a power management event coming up, how about that? */
145	if (pp->pms.pmsPop > 0 && pp->pms.pmsPop < deadline)
146		deadline = pp->pms.pmsPop;
147
148
149	if (deadline > 0 && deadline <= pp->rtcPop) {
150		int     decr;
151		uint64_t now;
152
153		now = mach_absolute_time();
154		decr = setPop(deadline);
155
156		if (deadline < now)
157		        pp->rtcPop = now + decr;
158		else
159		        pp->rtcPop = deadline;
160
161		KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_EXCP_DECI, 1) | DBG_FUNC_NONE, decr, 2, 0, 0, 0);
162	}
163	splx(s);
164}
165
166queue_t
167timer_queue_assign(
168	uint64_t		deadline)
169{
170	struct per_proc_info	*pp = getPerProc();
171	rtclock_timer_t			*timer;
172
173	if (pp->running) {
174		timer = &pp->rtclock_timer;
175
176		if (deadline < timer->deadline)
177			etimer_set_deadline(deadline);
178	}
179	else
180		timer = &PerProcTable[master_cpu].ppe_vaddr->rtclock_timer;
181
182	return (&timer->queue);
183}
184
185void
186timer_queue_cancel(
187	queue_t			queue,
188	uint64_t		deadline,
189	uint64_t		new_deadline)
190{
191	if (queue == &getPerProc()->rtclock_timer.queue) {
192		if (deadline < new_deadline)
193			etimer_set_deadline(new_deadline);
194	}
195}
196