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  */
35 
36 #include <sys/types.h>
37 #include <sys/systm.h>
38 #include <sys/kernel.h>
39 #include <sys/systimer.h>
40 #include <sys/sysctl.h>
41 #include <sys/signal.h>
42 #include <sys/interrupt.h>
43 #include <sys/bus.h>
44 #include <sys/time.h>
45 #include <machine/cpu.h>
46 #include <machine/clock.h>
47 #include <machine/globaldata.h>
48 #include <machine/md_var.h>
49 
50 #include <sys/thread2.h>
51 
52 #include <unistd.h>
53 #include <signal.h>
54 
55 #define VKTIMER_FREQ	1000000	/* 1us granularity */
56 
57 static void vktimer_intr(void *dummy, struct intrframe *frame);
58 
59 int disable_rtc_set;
60 SYSCTL_INT(_machdep, CPU_DISRTCSET, disable_rtc_set,
61 	   CTLFLAG_RW, &disable_rtc_set, 0, "");
62 SYSCTL_INT(_hw, OID_AUTO, tsc_present, CTLFLAG_RD,
63             &tsc_present, 0, "TSC Available");
64 SYSCTL_INT(_hw, OID_AUTO, tsc_invariant, CTLFLAG_RD,
65             &tsc_invariant, 0, "Invariant TSC");
66 SYSCTL_INT(_hw, OID_AUTO, tsc_mpsync, CTLFLAG_RD,
67             &tsc_mpsync, 0, "TSC is synchronized across CPUs");
68 SYSCTL_QUAD(_hw, OID_AUTO, tsc_frequency, CTLFLAG_RD,
69 	    &tsc_frequency, 0, "TSC Frequency");
70 
71 int adjkerntz;
72 int wall_cmos_clock = 0;
73 SYSCTL_INT(_machdep, CPU_WALLCLOCK, wall_cmos_clock,
74     CTLFLAG_RD, &wall_cmos_clock, 0, "");
75 
76 static struct kqueue_info *kqueue_timer_info;
77 
78 static int cputimer_mib[16];
79 static int cputimer_miblen;
80 
81 /*
82  * SYSTIMER IMPLEMENTATION
83  */
84 static sysclock_t vkernel_timer_get_timecount(void);
85 static void vkernel_timer_construct(struct cputimer *timer, sysclock_t oclock);
86 
87 static struct cputimer vkernel_cputimer = {
88         SLIST_ENTRY_INITIALIZER,
89         "VKERNEL",
90         CPUTIMER_PRI_VKERNEL,
91         CPUTIMER_VKERNEL,
92         vkernel_timer_get_timecount,
93         cputimer_default_fromhz,
94         cputimer_default_fromus,
95         vkernel_timer_construct,
96         cputimer_default_destruct,
97 	VKTIMER_FREQ,
98         0, 0, 0
99 };
100 
101 static void	vktimer_intr_reload(struct cputimer_intr *, sysclock_t);
102 static void	vktimer_intr_initclock(struct cputimer_intr *, boolean_t);
103 
104 static struct cputimer_intr vkernel_cputimer_intr = {
105 	.freq = VKTIMER_FREQ,
106 	.reload = vktimer_intr_reload,
107 	.enable = cputimer_intr_default_enable,
108 	.config = cputimer_intr_default_config,
109 	.restart = cputimer_intr_default_restart,
110 	.pmfixup = cputimer_intr_default_pmfixup,
111 	.initclock = vktimer_intr_initclock,
112 	.next = SLIST_ENTRY_INITIALIZER,
113 	.name = "vkernel",
114 	.type = CPUTIMER_INTR_VKERNEL,
115 	.prio = CPUTIMER_INTR_PRIO_VKERNEL,
116 	.caps = CPUTIMER_INTR_CAP_NONE
117 };
118 
119 /*
120  * Initialize the systimer subsystem, called from MI code in early boot.
121  */
122 static void
123 cpu_initclocks(void *arg __unused)
124 {
125 	size_t len;
126 
127 	kprintf("initclocks\n");
128 	len = sizeof(vkernel_cputimer.freq);
129 	if (sysctlbyname("kern.cputimer.freq", &vkernel_cputimer.freq, &len,
130 		         NULL, 0) < 0) {
131 		panic("cpu_initclocks: can't get kern.cputimer.freq!");
132 	}
133 	len = NELEM(cputimer_mib);
134 	if (sysctlnametomib("kern.cputimer.clock", cputimer_mib, &len) < 0)
135 		panic("cpu_initclocks: can't get kern.cputimer.clock!");
136 	cputimer_miblen = len;
137 
138 	cputimer_intr_register(&vkernel_cputimer_intr);
139 	cputimer_intr_select(&vkernel_cputimer_intr, 0);
140 
141 	cputimer_register(&vkernel_cputimer);
142 	cputimer_select(&vkernel_cputimer, 0);
143 }
144 SYSINIT(clocksvk, SI_BOOT2_CLOCKREG, SI_ORDER_FIRST, cpu_initclocks, NULL);
145 
146 /*
147  * Constructor to initialize timer->base and get an initial count.
148  */
149 static void
150 vkernel_timer_construct(struct cputimer *timer, sysclock_t oclock)
151 {
152 	timer->base = 0;
153 	timer->base = oclock - vkernel_timer_get_timecount();
154 }
155 
156 /*
157  * Get the current counter, with 2's complement rollover.
158  *
159  * NOTE! MPSAFE, possibly no critical section
160  */
161 static sysclock_t
162 vkernel_timer_get_timecount(void)
163 {
164 	sysclock_t counter;
165 	size_t len;
166 
167 	len = sizeof(counter);
168 	if (sysctl(cputimer_mib, cputimer_miblen, &counter, &len,
169 		   NULL, 0) < 0) {
170 		panic("vkernel_timer_get_timecount: sysctl failed!");
171 	}
172 	return(counter);
173 }
174 
175 /*
176  * Initialize the interrupt for our core systimer.  Use the kqueue timer
177  * support functions.
178  */
179 static void
180 vktimer_intr_initclock(struct cputimer_intr *cti __unused,
181 		       boolean_t selected __unused)
182 {
183 	KKASSERT(kqueue_timer_info == NULL);
184 	kqueue_timer_info = kqueue_add_timer(vktimer_intr, NULL);
185 }
186 
187 /*
188  * Reload the interrupt for our core systimer.  Because the caller's
189  * reload calculation can be negatively indexed, we need a minimal
190  * check to ensure that a reasonable reload value is selected.
191  */
192 static void
193 vktimer_intr_reload(struct cputimer_intr *cti __unused, sysclock_t reload)
194 {
195 	if (kqueue_timer_info) {
196 		if ((int)reload < 1)
197 			reload = 1;
198 		kqueue_reload_timer(kqueue_timer_info, (reload + 999) / 1000);
199 	}
200 }
201 
202 /*
203  * clock interrupt.
204  *
205  * NOTE: frame is a struct intrframe pointer.
206  */
207 static void
208 vktimer_intr(void *dummy, struct intrframe *frame)
209 {
210 	static sysclock_t sysclock_count;
211 	struct globaldata *gd = mycpu;
212         struct globaldata *gscan;
213 	int n;
214 
215 	sysclock_count = sys_cputimer->count();
216 	for (n = 0; n < ncpus; ++n) {
217 		gscan = globaldata_find(n);
218 		if (TAILQ_FIRST(&gscan->gd_systimerq) == NULL)
219 			continue;
220 		if (gscan != gd) {
221 			lwkt_send_ipiq3(gscan, (ipifunc3_t)systimer_intr,
222 					&sysclock_count, 0);
223 		} else {
224 			systimer_intr(&sysclock_count, 0, frame);
225 		}
226 	}
227 }
228 
229 /*
230  * Initialize the time of day register, based on the time base which is, e.g.
231  * from a filesystem.
232  */
233 void
234 inittodr(time_t base)
235 {
236 	struct timespec ts;
237 	struct timeval tv;
238 
239 	gettimeofday(&tv, NULL);
240 	ts.tv_sec = tv.tv_sec;
241 	ts.tv_nsec = tv.tv_usec * 1000;
242 	set_timeofday(&ts);
243 }
244 
245 /*
246  * Write system time back to the RTC
247  */
248 void
249 resettodr(void)
250 {
251 }
252 
253 /*
254  * We need to enter a critical section to prevent signals from recursing
255  * into pthreads.
256  */
257 void
258 DELAY(int usec)
259 {
260 	crit_enter();
261 	usleep(usec);
262 	crit_exit();
263 }
264 
265 void
266 DRIVERSLEEP(int usec)
267 {
268         if (mycpu->gd_intr_nesting_level)
269 		DELAY(usec);
270 	else if (1000000 / usec >= hz)
271 		tsleep(DRIVERSLEEP, 0, "DELAY", 1000000 / usec / hz + 1);
272 	else
273 		DELAY(usec);
274 }
275