xref: /titanic_41/usr/src/uts/sun4/os/mp_states.c (revision fd9cb95cbb2f626355a60efb9d02c5f0a33c10e6)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <sys/systm.h>
30 #include <sys/membar.h>
31 #include <sys/machsystm.h>
32 #include <sys/x_call.h>
33 #include <sys/platform_module.h>
34 #include <sys/cpuvar.h>
35 #include <sys/cpu_module.h>
36 #include <sys/cmp.h>
37 
38 #include <sys/cpu_sgnblk_defs.h>
39 
40 static cpuset_t cpu_idle_set;
41 static kmutex_t cpu_idle_lock;
42 typedef const char *fn_t;
43 
44 /*
45  * flags to determine if the PROM routines
46  * should be used to idle/resume/stop cpus
47  */
48 static int kern_idle[NCPU];		/* kernel's idle loop */
49 static int cpu_are_paused;
50 extern void debug_flush_windows();
51 
52 /*
53  * Initialize the idlestop mutex
54  */
55 void
56 idlestop_init(void)
57 {
58 	mutex_init(&cpu_idle_lock, NULL, MUTEX_SPIN, (void *)ipltospl(PIL_15));
59 }
60 
61 static void
62 cpu_idle_self(void)
63 {
64 	uint_t s;
65 	label_t save;
66 
67 	s = spl8();
68 	debug_flush_windows();
69 
70 	CPU->cpu_m.in_prom = 1;
71 	membar_stld();
72 
73 	save = curthread->t_pcb;
74 	(void) setjmp(&curthread->t_pcb);
75 
76 	kern_idle[CPU->cpu_id] = 1;
77 	while (kern_idle[CPU->cpu_id])
78 		/* SPIN */;
79 
80 	CPU->cpu_m.in_prom = 0;
81 	membar_stld();
82 
83 	curthread->t_pcb = save;
84 	splx(s);
85 }
86 
87 void
88 idle_other_cpus(void)
89 {
90 	int i, cpuid, ntries;
91 	int failed = 0;
92 
93 	if (ncpus == 1)
94 		return;
95 
96 	mutex_enter(&cpu_idle_lock);
97 
98 	cpuid = CPU->cpu_id;
99 	ASSERT(cpuid < NCPU);
100 
101 	cpu_idle_set = cpu_ready_set;
102 	CPUSET_DEL(cpu_idle_set, cpuid);
103 
104 	if (CPUSET_ISNULL(cpu_idle_set))
105 		return;
106 
107 	xt_some(cpu_idle_set, (xcfunc_t *)idle_stop_xcall,
108 	    (uint64_t)cpu_idle_self, NULL);
109 
110 	for (i = 0; i < NCPU; i++) {
111 		if (!CPU_IN_SET(cpu_idle_set, i))
112 			continue;
113 
114 		ntries = 0x10000;
115 		while (!cpu[i]->cpu_m.in_prom && ntries) {
116 			DELAY(50);
117 			ntries--;
118 		}
119 
120 		/*
121 		 * A cpu failing to idle is an error condition, since
122 		 * we can't be sure anymore of its state.
123 		 */
124 		if (!cpu[i]->cpu_m.in_prom) {
125 			cmn_err(CE_WARN, "cpuid 0x%x failed to idle", i);
126 			failed++;
127 		}
128 	}
129 
130 	if (failed) {
131 		mutex_exit(&cpu_idle_lock);
132 		cmn_err(CE_PANIC, "idle_other_cpus: not all cpus idled");
133 	}
134 }
135 
136 void
137 resume_other_cpus(void)
138 {
139 	int i, ntries;
140 	int cpuid = CPU->cpu_id;
141 	boolean_t failed = B_FALSE;
142 
143 	if (ncpus == 1)
144 		return;
145 
146 	ASSERT(cpuid < NCPU);
147 	ASSERT(MUTEX_HELD(&cpu_idle_lock));
148 
149 	for (i = 0; i < NCPU; i++) {
150 		if (!CPU_IN_SET(cpu_idle_set, i))
151 			continue;
152 
153 		kern_idle[i] = 0;
154 		membar_stld();
155 	}
156 
157 	for (i = 0; i < NCPU; i++) {
158 		if (!CPU_IN_SET(cpu_idle_set, i))
159 			continue;
160 
161 		ntries = 0x10000;
162 		while (cpu[i]->cpu_m.in_prom && ntries) {
163 			DELAY(50);
164 			ntries--;
165 		}
166 
167 		/*
168 		 * A cpu failing to resume is an error condition, since
169 		 * intrs may have been directed there.
170 		 */
171 		if (cpu[i]->cpu_m.in_prom) {
172 			cmn_err(CE_WARN, "cpuid 0x%x failed to resume", i);
173 			continue;
174 		}
175 		CPUSET_DEL(cpu_idle_set, i);
176 	}
177 
178 	failed = !CPUSET_ISNULL(cpu_idle_set);
179 
180 	mutex_exit(&cpu_idle_lock);
181 
182 	/*
183 	 * Non-zero if a cpu failed to resume
184 	 */
185 	if (failed)
186 		cmn_err(CE_PANIC, "resume_other_cpus: not all cpus resumed");
187 
188 }
189 
190 /*
191  * Stop all other cpu's before halting or rebooting. We pause the cpu's
192  * instead of sending a cross call.
193  */
194 void
195 stop_other_cpus(void)
196 {
197 	mutex_enter(&cpu_lock);
198 	if (cpu_are_paused) {
199 		mutex_exit(&cpu_lock);
200 		return;
201 	}
202 
203 	if (ncpus > 1)
204 		intr_redist_all_cpus_shutdown();
205 
206 	pause_cpus(NULL);
207 	cpu_are_paused = 1;
208 
209 	mutex_exit(&cpu_lock);
210 }
211 
212 int cpu_quiesce_microsecond_sanity_limit = 60 * 1000000;
213 
214 void
215 mp_cpu_quiesce(cpu_t *cp0)
216 {
217 
218 	volatile cpu_t  *cp = (volatile cpu_t *) cp0;
219 	int i, sanity_limit = cpu_quiesce_microsecond_sanity_limit;
220 	int		cpuid = cp->cpu_id;
221 	int 		found_intr = 1;
222 	static fn_t	f = "mp_cpu_quiesce";
223 
224 	ASSERT(CPU->cpu_id != cpuid);
225 	ASSERT(MUTEX_HELD(&cpu_lock));
226 	ASSERT(cp->cpu_flags & CPU_QUIESCED);
227 
228 
229 	/*
230 	 * Declare CPU as no longer being READY to process interrupts and
231 	 * wait for them to stop. A CPU that is not READY can no longer
232 	 * participate in x-calls or x-traps.
233 	 */
234 	cp->cpu_flags &= ~CPU_READY;
235 	CPUSET_DEL(cpu_ready_set, cpuid);
236 	membar_sync();
237 
238 	for (i = 0; i < sanity_limit; i++) {
239 		if (cp->cpu_intr_actv == 0 &&
240 		    cp->cpu_thread == cp->cpu_idle_thread) {
241 			found_intr = 0;
242 			break;
243 		}
244 		DELAY(1);
245 	}
246 
247 	if (found_intr) {
248 
249 		if (cp->cpu_intr_actv) {
250 			cmn_err(CE_PANIC, "%s: cpu_intr_actv != 0", f);
251 		} else if (cp->cpu_thread != cp->cpu_idle_thread) {
252 			cmn_err(CE_PANIC, "%s: cpu_thread != cpu_idle_thread",
253 				f);
254 		}
255 
256 	}
257 }
258 
259 /*
260  * Start CPU on user request.
261  */
262 /* ARGSUSED */
263 int
264 mp_cpu_start(struct cpu *cp)
265 {
266 	ASSERT(MUTEX_HELD(&cpu_lock));
267 	/*
268 	 * Platforms that use CPU signatures require the signature
269 	 * block update to indicate that this CPU is in the OS now.
270 	 */
271 	CPU_SIGNATURE(OS_SIG, SIGST_RUN, SIGSUBST_NULL, cp->cpu_id);
272 
273 	cmp_error_resteer(cp->cpu_id);
274 
275 	return (0);			/* nothing special to do on this arch */
276 }
277 
278 /*
279  * Stop CPU on user request.
280  */
281 /* ARGSUSED */
282 int
283 mp_cpu_stop(struct cpu *cp)
284 {
285 	ASSERT(MUTEX_HELD(&cpu_lock));
286 
287 	cmp_error_resteer(cp->cpu_id);
288 
289 	/*
290 	 * Platforms that use CPU signatures require the signature
291 	 * block update to indicate that this CPU is offlined now.
292 	 */
293 	CPU_SIGNATURE(OS_SIG, SIGST_OFFLINE, SIGSUBST_NULL, cp->cpu_id);
294 	return (0);			/* nothing special to do on this arch */
295 }
296 
297 /*
298  * Power on CPU.
299  */
300 int
301 mp_cpu_poweron(struct cpu *cp)
302 {
303 	ASSERT(MUTEX_HELD(&cpu_lock));
304 	if (&plat_cpu_poweron)
305 		return (plat_cpu_poweron(cp));	/* platform-dependent hook */
306 
307 	return (ENOTSUP);
308 }
309 
310 /*
311  * Power off CPU.
312  */
313 int
314 mp_cpu_poweroff(struct cpu *cp)
315 {
316 	ASSERT(MUTEX_HELD(&cpu_lock));
317 	if (&plat_cpu_poweroff)
318 		return (plat_cpu_poweroff(cp));	/* platform-dependent hook */
319 
320 	return (ENOTSUP);
321 }
322 
323 void
324 mp_cpu_faulted_enter(struct cpu *cp)
325 {
326 	cpu_faulted_enter(cp);
327 }
328 
329 void
330 mp_cpu_faulted_exit(struct cpu *cp)
331 {
332 	cpu_faulted_exit(cp);
333 }
334