xref: /netbsd-src/sys/arch/sparc/sparc/timer_sun4m.c (revision cb40c69b164a69aec47d70a50d23979d0f1752cb)
1 /*	$NetBSD: timer_sun4m.c,v 1.33 2023/06/02 08:51:47 andvar Exp $	*/
2 
3 /*
4  * Copyright (c) 1992, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  * Copyright (c) 1994 Gordon W. Ross
7  * Copyright (c) 1993 Adam Glass
8  * Copyright (c) 1996 Paul Kranenburg
9  * Copyright (c) 1996
10  * 	The President and Fellows of Harvard College. All rights reserved.
11  *
12  * This software was developed by the Computer Systems Engineering group
13  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
14  * contributed to Berkeley.
15  *
16  * All advertising materials mentioning features or use of this software
17  * must display the following acknowledgement:
18  *	This product includes software developed by Harvard University.
19  *	This product includes software developed by the University of
20  *	California, Lawrence Berkeley Laboratory.
21  *
22  * Redistribution and use in source and binary forms, with or without
23  * modification, are permitted provided that the following conditions
24  * are met:
25  *
26  * 1. Redistributions of source code must retain the above copyright
27  *    notice, this list of conditions and the following disclaimer.
28  * 2. Redistributions in binary form must reproduce the above copyright
29  *    notice, this list of conditions and the following disclaimer in the
30  *    documentation and/or other materials provided with the distribution.
31  * 3. All advertising materials mentioning features or use of this software
32  *    must display the following acknowledgement:
33  *	This product includes software developed by the University of
34  *	California, Berkeley and its contributors.
35  *	This product includes software developed by Paul Kranenburg.
36  *	This product includes software developed by Harvard University.
37  * 4. Neither the name of the University nor the names of its contributors
38  *    may be used to endorse or promote products derived from this software
39  *    without specific prior written permission.
40  *
41  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51  * SUCH DAMAGE.
52  *
53  *	@(#)clock.c	8.1 (Berkeley) 6/11/93
54  */
55 
56 /*
57  * Sun4m timer support.
58  */
59 
60 #include <sys/cdefs.h>
61 __KERNEL_RCSID(0, "$NetBSD: timer_sun4m.c,v 1.33 2023/06/02 08:51:47 andvar Exp $");
62 
63 #include <sys/param.h>
64 #include <sys/kernel.h>
65 #include <sys/device.h>
66 #include <sys/systm.h>
67 #include <sys/cpu.h>
68 
69 #include <machine/autoconf.h>
70 #include <sys/bus.h>
71 
72 #include <sparc/sparc/vaddrs.h>
73 #include <sparc/sparc/cpuvar.h>
74 #include <sparc/sparc/timerreg.h>
75 #include <sparc/sparc/timervar.h>
76 
77 static struct timer_4m		*timerreg4m;
78 #define	counterreg4m	cpuinfo.counterreg_4m
79 
80 /*
81  * SMP hardclock handler.
82  */
83 #define IPL_HARDCLOCK	10
84 
85 /*
86  * Set up the real-time and statistics clocks.
87  * Leave stathz 0 only if no alternative timer is available.
88  *
89  * The frequencies of these clocks must be an even number of microseconds.
90  */
91 void
timer_init_4m(void)92 timer_init_4m(void)
93 {
94 	struct cpu_info *cpi;
95 	CPU_INFO_ITERATOR n;
96 
97 	timerreg4m->t_limit = tmr_ustolim4m(tick);
98 	for (CPU_INFO_FOREACH(n, cpi)) {
99 		cpi->counterreg_4m->t_limit = tmr_ustolim4m(statint);
100 	}
101 	icr_si_bic(SINTR_T);
102 }
103 
104 #ifdef MULTIPROCESSOR
105 /*
106  * Handle SMP hardclock() calling for this CPU.
107  */
108 static void
hardclock_ipi(void * cap)109 hardclock_ipi(void *cap)
110 {
111 	int s = splsched();
112 
113 	hardclock((struct clockframe *)cap);
114 	splx(s);
115 }
116 #endif
117 
118 /*
119  * Call hardclock on all CPUs.
120  */
121 static void
handle_hardclock(struct clockframe * cap)122 handle_hardclock(struct clockframe *cap)
123 {
124 	int s;
125 #ifdef MULTIPROCESSOR
126 	struct cpu_info *cpi;
127 	CPU_INFO_ITERATOR n;
128 
129 	for (CPU_INFO_FOREACH(n, cpi)) {
130 		if (cpi == cpuinfo.ci_self) {
131 			KASSERT(CPU_IS_PRIMARY(cpi));
132 			continue;
133 		}
134 
135 		raise_ipi(cpi, IPL_HARDCLOCK);
136 	}
137 #endif
138 	s = splsched();
139 	hardclock(cap);
140 	splx(s);
141 }
142 
143 /*
144  * Level 10 (clock) interrupts from system counter.
145  */
146 int
clockintr_4m(void * cap)147 clockintr_4m(void *cap)
148 {
149 
150 	/*
151 	 * XXX this needs to be fixed in a more general way
152 	 * problem is that the kernel enables interrupts and THEN
153 	 * sets up clocks. In between there's an opportunity to catch
154 	 * a timer interrupt - if we call hardclock() at that point we'll
155 	 * panic
156 	 * so for now just bail when cold
157 	 *
158 	 * For MP, we defer calling hardclock() to the schedintr so
159 	 * that we call it on all cpus.
160 	 */
161 	if (cold)
162 		return 0;
163 
164 	kpreempt_disable();
165 
166 	/* Read the limit register to clear the interrupt. */
167 	*((volatile int *)&timerreg4m->t_limit);
168 
169 	/* Update the timecounter offset. */
170 	tickle_tc();
171 
172 	/*
173 	 * We don't have a system-clock per-cpu, and we'd like to keep
174 	 * the per-cpu timer for the statclock, so, send an IPI to
175 	 * everyone to call hardclock.
176 	 */
177 	handle_hardclock(cap);
178 
179 	kpreempt_enable();
180 	return (1);
181 }
182 
183 /*
184  * Level 14 (stat clock) interrupts from processor counter.
185  */
186 int
statintr_4m(void * cap)187 statintr_4m(void *cap)
188 {
189 	struct clockframe *frame = cap;
190 	u_long newint;
191 
192 	kpreempt_disable();
193 
194 	/* read the limit register to clear the interrupt */
195 	*((volatile int *)&counterreg4m->t_limit);
196 
197 	statclock(frame);
198 
199 	/*
200 	 * Compute new randomized interval.
201 	 */
202 	newint = new_interval();
203 
204 	/*
205 	 * Use the `non-resetting' limit register, so we don't
206 	 * lose the counter ticks that happened since this
207 	 * interrupt was raised.
208 	 */
209 	counterreg4m->t_limit_nr = tmr_ustolim4m(newint);
210 
211 	/*
212 	 * The factor 8 is only valid for stathz==100.
213 	 * See also clock.c
214 	 */
215 	if ((++cpuinfo.ci_schedstate.spc_schedticks & 7) == 0 && schedhz != 0) {
216 		if (CLKF_LOPRI(frame, IPL_SCHED)) {
217 			/* No need to schedule a soft interrupt */
218 			spllowerschedclock();
219 			schedintr(cap);
220 		} else {
221 			/*
222 			 * We're interrupting a thread that may have the
223 			 * scheduler lock; run schedintr() on this CPU later.
224 			 */
225 			raise_ipi(&cpuinfo, IPL_SCHED); /* sched_cookie->pil */
226 		}
227 	}
228 	kpreempt_enable();
229 
230 	return (1);
231 }
232 
233 void
timerattach_obio_4m(device_t parent,device_t self,void * aux)234 timerattach_obio_4m(device_t parent, device_t self, void *aux)
235 {
236 	union obio_attach_args *uoba = aux;
237 	struct sbus_attach_args *sa = &uoba->uoba_sbus;
238 	struct cpu_info *cpi;
239 	bus_space_handle_t bh;
240 	int i;
241 	CPU_INFO_ITERATOR n;
242 
243 	if (sa->sa_nreg < 2) {
244 		printf(": only %d register sets\n", sa->sa_nreg);
245 		return;
246 	}
247 
248 	/* Map the system timer */
249 	i = sa->sa_nreg - 1;
250 	if (bus_space_map2(sa->sa_bustag,
251 			   BUS_ADDR(sa->sa_reg[i].oa_space,
252 				    sa->sa_reg[i].oa_base),
253 			   sizeof(struct timer_4m),
254 			   BUS_SPACE_MAP_LINEAR,
255 			   TIMERREG_VA, &bh) != 0) {
256 		printf(": can't map registers\n");
257 		return;
258 	}
259 	timerreg4m = (struct timer_4m *)TIMERREG_VA;
260 
261 	/* Map each CPU's counter */
262 	for (i = 0; i < sa->sa_nreg - 1; i++) {
263 		/*
264 		 * Check whether the CPU corresponding to this timer
265 		 * register is installed.
266 		 */
267 		for (CPU_INFO_FOREACH(n, cpi)) {
268 			if ((i == 0 && sparc_ncpus == 1) || cpi->mid == i + 8) {
269 				/* We got a corresponding MID. */
270 				break;
271 			}
272 			cpi = NULL;
273 		}
274 		if (cpi == NULL)
275 			continue;
276 
277 		if (sbus_bus_map(sa->sa_bustag,
278 				 sa->sa_reg[i].oa_space,
279 				 sa->sa_reg[i].oa_base,
280 				 sizeof(struct timer_4m),
281 				 BUS_SPACE_MAP_LINEAR,
282 				 &bh) != 0) {
283 			printf(": can't map CPU counter %d\n", i);
284 			return;
285 		}
286 		cpi->counterreg_4m = (struct counter_4m *)bh;
287 	}
288 
289 #if defined(MULTIPROCESSOR)
290 	if (sparc_ncpus > 1) {
291 		/*
292 		 * Note that we don't actually use this cookie after checking
293 		 * it was established, we call directly via raise_ipi() on
294 		 * IPL_HARDCLOCK.
295 		 */
296 		void *hardclock_cookie;
297 
298 		hardclock_cookie = sparc_softintr_establish(IPL_HARDCLOCK,
299 		    hardclock_ipi, NULL);
300 		if (hardclock_cookie == NULL)
301 			panic("timerattach: cannot establish hardclock_intr");
302 	}
303 #endif
304 
305 	/* Put processor counter in "timer" mode */
306 	timerreg4m->t_cfg = 0;
307 
308 	timerattach(&timerreg4m->t_counter, &timerreg4m->t_limit);
309 }
310