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