xref: /freebsd/sys/powerpc/powerpc/mp_machdep.c (revision e0656a491411fe65ed8b9135add026358b24951f)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2008 Marcel Moolenaar
5  * All rights reserved.
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 the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/kernel.h>
35 #include <sys/ktr.h>
36 #include <sys/bus.h>
37 #include <sys/cpuset.h>
38 #include <sys/lock.h>
39 #include <sys/malloc.h>
40 #include <sys/mutex.h>
41 #include <sys/pcpu.h>
42 #include <sys/proc.h>
43 #include <sys/sched.h>
44 #include <sys/smp.h>
45 
46 #include <vm/vm.h>
47 #include <vm/vm_param.h>
48 #include <vm/pmap.h>
49 #include <vm/vm_map.h>
50 #include <vm/vm_extern.h>
51 #include <vm/vm_kern.h>
52 
53 #include <machine/bus.h>
54 #include <machine/cpu.h>
55 #include <machine/intr_machdep.h>
56 #include <machine/pcb.h>
57 #include <machine/platform.h>
58 #include <machine/md_var.h>
59 #include <machine/setjmp.h>
60 #include <machine/smp.h>
61 
62 #include "pic_if.h"
63 
64 extern struct pcpu __pcpu[MAXCPU];
65 
66 volatile static int ap_awake;
67 volatile static u_int ap_letgo;
68 volatile static u_quad_t ap_timebase;
69 static u_int ipi_msg_cnt[32];
70 static struct mtx ap_boot_mtx;
71 struct pcb stoppcbs[MAXCPU];
72 
73 void
74 machdep_ap_bootstrap(void)
75 {
76 
77 	PCPU_SET(awake, 1);
78 	__asm __volatile("msync; isync");
79 
80 	while (ap_letgo == 0)
81 		__asm __volatile("or 27,27,27");
82 	__asm __volatile("or 6,6,6");
83 
84 	/* Give platform code a chance to do anything necessary */
85 	platform_smp_ap_init();
86 
87 	/* Initialize DEC and TB, sync with the BSP values */
88 	platform_smp_timebase_sync(ap_timebase, 1);
89 	decr_ap_init();
90 
91 	/* Serialize console output and AP count increment */
92 	mtx_lock_spin(&ap_boot_mtx);
93 	ap_awake++;
94 	printf("SMP: AP CPU #%d launched\n", PCPU_GET(cpuid));
95 	mtx_unlock_spin(&ap_boot_mtx);
96 
97 	while(smp_started == 0)
98 		;
99 
100 	/* Start per-CPU event timers. */
101 	cpu_initclocks_ap();
102 
103 	/* Announce ourselves awake, and enter the scheduler */
104 	sched_throw(NULL);
105 }
106 
107 void
108 cpu_mp_setmaxid(void)
109 {
110 	struct cpuref cpuref;
111 	int error;
112 
113 	mp_ncpus = 0;
114 	mp_maxid = 0;
115 	error = platform_smp_first_cpu(&cpuref);
116 	while (!error) {
117 		mp_ncpus++;
118 		mp_maxid = max(cpuref.cr_cpuid, mp_maxid);
119 		error = platform_smp_next_cpu(&cpuref);
120 	}
121 	/* Sanity. */
122 	if (mp_ncpus == 0)
123 		mp_ncpus = 1;
124 }
125 
126 int
127 cpu_mp_probe(void)
128 {
129 
130 	/*
131 	 * We're not going to enable SMP if there's only 1 processor.
132 	 */
133 	return (mp_ncpus > 1);
134 }
135 
136 void
137 cpu_mp_start(void)
138 {
139 	struct cpuref bsp, cpu;
140 	struct pcpu *pc;
141 	int error;
142 
143 	error = platform_smp_get_bsp(&bsp);
144 	KASSERT(error == 0, ("Don't know BSP"));
145 
146 	error = platform_smp_first_cpu(&cpu);
147 	while (!error) {
148 		if (cpu.cr_cpuid >= MAXCPU) {
149 			printf("SMP: cpu%d: skipped -- ID out of range\n",
150 			    cpu.cr_cpuid);
151 			goto next;
152 		}
153 		if (CPU_ISSET(cpu.cr_cpuid, &all_cpus)) {
154 			printf("SMP: cpu%d: skipped - duplicate ID\n",
155 			    cpu.cr_cpuid);
156 			goto next;
157 		}
158 		if (cpu.cr_cpuid != bsp.cr_cpuid) {
159 			void *dpcpu;
160 
161 			pc = &__pcpu[cpu.cr_cpuid];
162 			dpcpu = (void *)kmem_malloc(kernel_arena, DPCPU_SIZE,
163 			    M_WAITOK | M_ZERO);
164 			pcpu_init(pc, cpu.cr_cpuid, sizeof(*pc));
165 			dpcpu_init(dpcpu, cpu.cr_cpuid);
166 		} else {
167 			pc = pcpup;
168 			pc->pc_cpuid = bsp.cr_cpuid;
169 			pc->pc_bsp = 1;
170 		}
171 		pc->pc_hwref = cpu.cr_hwref;
172 		CPU_SET(pc->pc_cpuid, &all_cpus);
173 next:
174 		error = platform_smp_next_cpu(&cpu);
175 	}
176 }
177 
178 void
179 cpu_mp_announce(void)
180 {
181 	struct pcpu *pc;
182 	int i;
183 
184 	if (!bootverbose)
185 		return;
186 
187 	CPU_FOREACH(i) {
188 		pc = pcpu_find(i);
189 		if (pc == NULL)
190 			continue;
191 		printf("cpu%d: dev=%x", i, (int)pc->pc_hwref);
192 		if (pc->pc_bsp)
193 			printf(" (BSP)");
194 		printf("\n");
195 	}
196 }
197 
198 static void
199 cpu_mp_unleash(void *dummy)
200 {
201 	struct pcpu *pc;
202 	int cpus, timeout;
203 	int ret;
204 
205 	if (mp_ncpus <= 1)
206 		return;
207 
208 	mtx_init(&ap_boot_mtx, "ap boot", NULL, MTX_SPIN);
209 
210 	cpus = 0;
211 	smp_cpus = 0;
212 #ifdef BOOKE
213 	tlb1_ap_prep();
214 #endif
215 	STAILQ_FOREACH(pc, &cpuhead, pc_allcpu) {
216 		cpus++;
217 		if (!pc->pc_bsp) {
218 			if (bootverbose)
219 				printf("Waking up CPU %d (dev=%x)\n",
220 				    pc->pc_cpuid, (int)pc->pc_hwref);
221 
222 			ret = platform_smp_start_cpu(pc);
223 			if (ret == 0) {
224 				timeout = 2000;	/* wait 2sec for the AP */
225 				while (!pc->pc_awake && --timeout > 0)
226 					DELAY(1000);
227 			}
228 		} else {
229 			pc->pc_awake = 1;
230 		}
231 		if (pc->pc_awake) {
232 			if (bootverbose)
233 				printf("Adding CPU %d, hwref=%jx, awake=%x\n",
234 				    pc->pc_cpuid, (uintmax_t)pc->pc_hwref,
235 				    pc->pc_awake);
236 			smp_cpus++;
237 		} else
238 			CPU_SET(pc->pc_cpuid, &stopped_cpus);
239 	}
240 
241 	ap_awake = 1;
242 
243 	/* Provide our current DEC and TB values for APs */
244 	ap_timebase = mftb() + 10;
245 	__asm __volatile("msync; isync");
246 
247 	/* Let APs continue */
248 	atomic_store_rel_int(&ap_letgo, 1);
249 
250 	platform_smp_timebase_sync(ap_timebase, 0);
251 
252 	while (ap_awake < smp_cpus)
253 		;
254 
255 	if (smp_cpus != cpus || cpus != mp_ncpus) {
256 		printf("SMP: %d CPUs found; %d CPUs usable; %d CPUs woken\n",
257 		    mp_ncpus, cpus, smp_cpus);
258 	}
259 
260 	if (smp_cpus > 1)
261 		atomic_store_rel_int(&smp_started, 1);
262 
263 	/* Let the APs get into the scheduler */
264 	DELAY(10000);
265 
266 }
267 
268 SYSINIT(start_aps, SI_SUB_SMP, SI_ORDER_FIRST, cpu_mp_unleash, NULL);
269 
270 int
271 powerpc_ipi_handler(void *arg)
272 {
273 	u_int cpuid;
274 	uint32_t ipimask;
275 	int msg;
276 
277 	CTR2(KTR_SMP, "%s: MSR 0x%08x", __func__, mfmsr());
278 
279 	ipimask = atomic_readandclear_32(&(pcpup->pc_ipimask));
280 	if (ipimask == 0)
281 		return (FILTER_STRAY);
282 	while ((msg = ffs(ipimask) - 1) != -1) {
283 		ipimask &= ~(1u << msg);
284 		ipi_msg_cnt[msg]++;
285 		switch (msg) {
286 		case IPI_AST:
287 			CTR1(KTR_SMP, "%s: IPI_AST", __func__);
288 			break;
289 		case IPI_PREEMPT:
290 			CTR1(KTR_SMP, "%s: IPI_PREEMPT", __func__);
291 			sched_preempt(curthread);
292 			break;
293 		case IPI_RENDEZVOUS:
294 			CTR1(KTR_SMP, "%s: IPI_RENDEZVOUS", __func__);
295 			smp_rendezvous_action();
296 			break;
297 		case IPI_STOP:
298 
299 			/*
300 			 * IPI_STOP_HARD is mapped to IPI_STOP so it is not
301 			 * necessary to add such case in the switch.
302 			 */
303 			CTR1(KTR_SMP, "%s: IPI_STOP or IPI_STOP_HARD (stop)",
304 			    __func__);
305 			cpuid = PCPU_GET(cpuid);
306 			savectx(&stoppcbs[cpuid]);
307 			savectx(PCPU_GET(curpcb));
308 			CPU_SET_ATOMIC(cpuid, &stopped_cpus);
309 			while (!CPU_ISSET(cpuid, &started_cpus))
310 				cpu_spinwait();
311 			CPU_CLR_ATOMIC(cpuid, &stopped_cpus);
312 			CPU_CLR_ATOMIC(cpuid, &started_cpus);
313 			CTR1(KTR_SMP, "%s: IPI_STOP (restart)", __func__);
314 			break;
315 		case IPI_HARDCLOCK:
316 			CTR1(KTR_SMP, "%s: IPI_HARDCLOCK", __func__);
317 			hardclockintr();
318 			break;
319 		}
320 	}
321 
322 	return (FILTER_HANDLED);
323 }
324 
325 static void
326 ipi_send(struct pcpu *pc, int ipi)
327 {
328 
329 	CTR4(KTR_SMP, "%s: pc=%p, targetcpu=%d, IPI=%d", __func__,
330 	    pc, pc->pc_cpuid, ipi);
331 
332 	atomic_set_32(&pc->pc_ipimask, (1 << ipi));
333 	powerpc_sync();
334 	PIC_IPI(root_pic, pc->pc_cpuid);
335 
336 	CTR1(KTR_SMP, "%s: sent", __func__);
337 }
338 
339 /* Send an IPI to a set of cpus. */
340 void
341 ipi_selected(cpuset_t cpus, int ipi)
342 {
343 	struct pcpu *pc;
344 
345 	STAILQ_FOREACH(pc, &cpuhead, pc_allcpu) {
346 		if (CPU_ISSET(pc->pc_cpuid, &cpus))
347 			ipi_send(pc, ipi);
348 	}
349 }
350 
351 /* Send an IPI to a specific CPU. */
352 void
353 ipi_cpu(int cpu, u_int ipi)
354 {
355 
356 	ipi_send(cpuid_to_pcpu[cpu], ipi);
357 }
358 
359 /* Send an IPI to all CPUs EXCEPT myself. */
360 void
361 ipi_all_but_self(int ipi)
362 {
363 	struct pcpu *pc;
364 
365 	STAILQ_FOREACH(pc, &cpuhead, pc_allcpu) {
366 		if (pc != pcpup)
367 			ipi_send(pc, ipi);
368 	}
369 }
370