1 /*
2  * Copyright (c) 2006 The DragonFly Project.  All rights reserved.
3  *
4  * This code is derived from software contributed to The DragonFly Project
5  * by Matthew Dillon <dillon@backplane.com>
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in
15  *    the documentation and/or other materials provided with the
16  *    distribution.
17  * 3. Neither the name of The DragonFly Project nor the names of its
18  *    contributors may be used to endorse or promote products derived
19  *    from this software without specific, prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  * $DragonFly: src/sys/platform/vkernel/platform/systimer.c,v 1.17 2008/06/06 13:19:25 swildner Exp $
35  */
36 
37 #include <sys/types.h>
38 #include <sys/systm.h>
39 #include <sys/kernel.h>
40 #include <sys/systimer.h>
41 #include <sys/sysctl.h>
42 #include <sys/signal.h>
43 #include <sys/interrupt.h>
44 #include <sys/bus.h>
45 #include <sys/time.h>
46 #include <machine/cpu.h>
47 #include <machine/clock.h>
48 #include <machine/globaldata.h>
49 #include <machine/md_var.h>
50 
51 #include <sys/thread2.h>
52 
53 #include <unistd.h>
54 #include <signal.h>
55 
56 #define VKTIMER_FREQ	1000000	/* 1us granularity */
57 
58 static void vktimer_intr(void *dummy, struct intrframe *frame);
59 
60 int disable_rtc_set;
61 SYSCTL_INT(_machdep, CPU_DISRTCSET, disable_rtc_set,
62 	   CTLFLAG_RW, &disable_rtc_set, 0, "");
63 SYSCTL_INT(_hw, OID_AUTO, tsc_present, CTLFLAG_RD,
64             &tsc_present, 0, "TSC Available");
65 SYSCTL_QUAD(_hw, OID_AUTO, tsc_frequency, CTLFLAG_RD,
66 	    &tsc_frequency, 0, "TSC Frequency");
67 
68 int adjkerntz;
69 int wall_cmos_clock = 0;
70 static struct kqueue_info *kqueue_timer_info;
71 
72 static int cputimer_mib[16];
73 static int cputimer_miblen;
74 
75 /*
76  * SYSTIMER IMPLEMENTATION
77  */
78 static sysclock_t vkernel_timer_get_timecount(void);
79 static void vkernel_timer_construct(struct cputimer *timer, sysclock_t oclock);
80 
81 static struct cputimer vkernel_cputimer = {
82         SLIST_ENTRY_INITIALIZER,
83         "VKERNEL",
84         CPUTIMER_PRI_VKERNEL,
85         CPUTIMER_VKERNEL,
86         vkernel_timer_get_timecount,
87         cputimer_default_fromhz,
88         cputimer_default_fromus,
89         vkernel_timer_construct,
90         cputimer_default_destruct,
91 	VKTIMER_FREQ,
92         0, 0, 0
93 };
94 
95 static void	vktimer_intr_reload(struct cputimer_intr *, sysclock_t);
96 static void	vktimer_intr_initclock(struct cputimer_intr *, boolean_t);
97 
98 static struct cputimer_intr vkernel_cputimer_intr = {
99 	.freq = VKTIMER_FREQ,
100 	.reload = vktimer_intr_reload,
101 	.enable = cputimer_intr_default_enable,
102 	.config = cputimer_intr_default_config,
103 	.restart = cputimer_intr_default_restart,
104 	.pmfixup = cputimer_intr_default_pmfixup,
105 	.initclock = vktimer_intr_initclock,
106 	.next = SLIST_ENTRY_INITIALIZER,
107 	.name = "vkernel",
108 	.type = CPUTIMER_INTR_VKERNEL,
109 	.prio = CPUTIMER_INTR_PRIO_VKERNEL,
110 	.caps = CPUTIMER_INTR_CAP_NONE
111 };
112 
113 /*
114  * Initialize the systimer subsystem, called from MI code in early boot.
115  */
116 static void
117 cpu_initclocks(void *arg __unused)
118 {
119 	size_t len;
120 
121 	kprintf("initclocks\n");
122 	len = sizeof(vkernel_cputimer.freq);
123 	if (sysctlbyname("kern.cputimer.freq", &vkernel_cputimer.freq, &len,
124 		         NULL, 0) < 0) {
125 		panic("cpu_initclocks: can't get kern.cputimer.freq!");
126 	}
127 	len = sizeof(cputimer_mib)/sizeof(cputimer_mib[0]);
128 	if (sysctlnametomib("kern.cputimer.clock", cputimer_mib, &len) < 0)
129 		panic("cpu_initclocks: can't get kern.cputimer.clock!");
130 	cputimer_miblen = len;
131 
132 	cputimer_intr_register(&vkernel_cputimer_intr);
133 	cputimer_intr_select(&vkernel_cputimer_intr, 0);
134 
135 	cputimer_register(&vkernel_cputimer);
136 	cputimer_select(&vkernel_cputimer, 0);
137 }
138 SYSINIT(clocksvk, SI_BOOT2_CLOCKREG, SI_ORDER_FIRST, cpu_initclocks, NULL)
139 
140 /*
141  * Constructor to initialize timer->base and get an initial count.
142  */
143 static void
144 vkernel_timer_construct(struct cputimer *timer, sysclock_t oclock)
145 {
146 	timer->base = 0;
147 	timer->base = oclock - vkernel_timer_get_timecount();
148 }
149 
150 /*
151  * Get the current counter, with 2's complement rollover.
152  *
153  * NOTE! MPSAFE, possibly no critical section
154  */
155 static sysclock_t
156 vkernel_timer_get_timecount(void)
157 {
158 	sysclock_t counter;
159 	size_t len;
160 
161 	len = sizeof(counter);
162 	if (sysctl(cputimer_mib, cputimer_miblen, &counter, &len,
163 		   NULL, 0) < 0) {
164 		panic("vkernel_timer_get_timecount: sysctl failed!");
165 	}
166 	return(counter);
167 }
168 
169 /*
170  * Initialize the interrupt for our core systimer.  Use the kqueue timer
171  * support functions.
172  */
173 static void
174 vktimer_intr_initclock(struct cputimer_intr *cti __unused,
175 		       boolean_t selected __unused)
176 {
177 	KKASSERT(kqueue_timer_info == NULL);
178 	kqueue_timer_info = kqueue_add_timer(vktimer_intr, NULL);
179 }
180 
181 /*
182  * Reload the interrupt for our core systimer.  Because the caller's
183  * reload calculation can be negatively indexed, we need a minimal
184  * check to ensure that a reasonable reload value is selected.
185  */
186 static void
187 vktimer_intr_reload(struct cputimer_intr *cti __unused, sysclock_t reload)
188 {
189 	if (kqueue_timer_info) {
190 		if ((int)reload < 1)
191 			reload = 1;
192 		kqueue_reload_timer(kqueue_timer_info, (reload + 999) / 1000);
193 	}
194 }
195 
196 /*
197  * clock interrupt.
198  *
199  * NOTE: frame is a struct intrframe pointer.
200  */
201 static void
202 vktimer_intr(void *dummy, struct intrframe *frame)
203 {
204 	static sysclock_t sysclock_count;
205 	struct globaldata *gd = mycpu;
206 #ifdef SMP
207         struct globaldata *gscan;
208 	int n;
209 #endif
210 
211 	sysclock_count = sys_cputimer->count();
212 #ifdef SMP
213 	for (n = 0; n < ncpus; ++n) {
214 		gscan = globaldata_find(n);
215 		if (TAILQ_FIRST(&gscan->gd_systimerq) == NULL)
216 			continue;
217 		if (gscan != gd) {
218 			lwkt_send_ipiq3(gscan, (ipifunc3_t)systimer_intr,
219 					&sysclock_count, 0);
220 		} else {
221 			systimer_intr(&sysclock_count, 0, frame);
222 		}
223 	}
224 #else
225 	if (TAILQ_FIRST(&gd->gd_systimerq) != NULL)
226 		systimer_intr(&sysclock_count, 0, frame);
227 #endif
228 }
229 
230 /*
231  * Initialize the time of day register, based on the time base which is, e.g.
232  * from a filesystem.
233  */
234 void
235 inittodr(time_t base)
236 {
237 	struct timespec ts;
238 	struct timeval tv;
239 
240 	gettimeofday(&tv, NULL);
241 	ts.tv_sec = tv.tv_sec;
242 	ts.tv_nsec = tv.tv_usec * 1000;
243 	set_timeofday(&ts);
244 }
245 
246 /*
247  * Write system time back to the RTC
248  */
249 void
250 resettodr(void)
251 {
252 }
253 
254 /*
255  * We need to enter a critical section to prevent signals from recursing
256  * into pthreads.
257  */
258 void
259 DELAY(int usec)
260 {
261 	crit_enter();
262 	usleep(usec);
263 	crit_exit();
264 }
265 
266 void
267 DRIVERSLEEP(int usec)
268 {
269         if (mycpu->gd_intr_nesting_level)
270 		DELAY(usec);
271 	else if (1000000 / usec >= hz)
272 		tsleep(DRIVERSLEEP, 0, "DELAY", 1000000 / usec / hz + 1);
273 	else
274 		DELAY(usec);
275 }
276