xref: /freebsd/sys/arm/arm/mp_machdep.c (revision 069ac184)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2011 Semihalf.
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  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 #include "opt_ddb.h"
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/bus.h>
33 #include <sys/kernel.h>
34 #include <sys/lock.h>
35 #include <sys/mutex.h>
36 #include <sys/proc.h>
37 #include <sys/pcpu.h>
38 #include <sys/sched.h>
39 #include <sys/smp.h>
40 #include <sys/ktr.h>
41 #include <sys/malloc.h>
42 
43 #include <vm/vm.h>
44 #include <vm/vm_extern.h>
45 #include <vm/vm_kern.h>
46 #include <vm/pmap.h>
47 
48 #include <machine/armreg.h>
49 #include <machine/cpu.h>
50 #include <machine/cpufunc.h>
51 #include <machine/debug_monitor.h>
52 #include <machine/smp.h>
53 #include <machine/pcb.h>
54 #include <machine/intr.h>
55 #include <machine/vmparam.h>
56 #ifdef VFP
57 #include <machine/vfp.h>
58 #endif
59 #ifdef CPU_MV_PJ4B
60 #include <arm/mv/mvwin.h>
61 #endif
62 
63 /* used to hold the AP's until we are ready to release them */
64 struct mtx ap_boot_mtx;
65 
66 /* # of Applications processors */
67 volatile int mp_naps;
68 
69 /* Set to 1 once we're ready to let the APs out of the pen. */
70 volatile int aps_ready = 0;
71 
72 void set_stackptrs(int cpu);
73 
74 /* Temporary variables for init_secondary()  */
75 void *dpcpu[MAXCPU - 1];
76 
77 /* Determine if we running MP machine */
78 int
79 cpu_mp_probe(void)
80 {
81 
82 	KASSERT(mp_ncpus != 0, ("cpu_mp_probe: mp_ncpus is unset"));
83 
84 	CPU_SETOF(0, &all_cpus);
85 
86 	return (mp_ncpus > 1);
87 }
88 
89 /* Start Application Processor via platform specific function */
90 static int
91 check_ap(void)
92 {
93 	uint32_t ms;
94 
95 	for (ms = 0; ms < 2000; ++ms) {
96 		if ((mp_naps + 1) == mp_ncpus)
97 			return (0);		/* success */
98 		else
99 			DELAY(1000);
100 	}
101 
102 	return (-2);
103 }
104 
105 /* Initialize and fire up non-boot processors */
106 void
107 cpu_mp_start(void)
108 {
109 	int error, i;
110 
111 	mtx_init(&ap_boot_mtx, "ap boot", NULL, MTX_SPIN);
112 
113 	/* Reserve memory for application processors */
114 	for(i = 0; i < (mp_ncpus - 1); i++)
115 		dpcpu[i] = kmem_malloc(DPCPU_SIZE, M_WAITOK | M_ZERO);
116 
117 	dcache_wbinv_poc_all();
118 
119 	/* Initialize boot code and start up processors */
120 	platform_mp_start_ap();
121 
122 	/*  Check if ap's started properly */
123 	error = check_ap();
124 	if (error)
125 		printf("WARNING: Some AP's failed to start\n");
126 	else
127 		for (i = 1; i < mp_ncpus; i++)
128 			CPU_SET(i, &all_cpus);
129 }
130 
131 /* Introduce rest of cores to the world */
132 void
133 cpu_mp_announce(void)
134 {
135 
136 }
137 
138 void
139 init_secondary(int cpu)
140 {
141 	struct pcpu *pc;
142 	uint32_t loop_counter;
143 
144 	pmap_set_tex();
145 	cpuinfo_reinit_mmu(pmap_kern_ttb);
146 	cpu_setup();
147 
148 	/* Provide stack pointers for other processor modes. */
149 	set_stackptrs(cpu);
150 
151 	enable_interrupts(PSR_A);
152 	pc = &__pcpu[cpu];
153 
154 	/*
155 	 * pcpu_init() updates queue, so it should not be executed in parallel
156 	 * on several cores
157 	 */
158 	while(mp_naps < (cpu - 1))
159 		;
160 
161 	pcpu_init(pc, cpu, sizeof(struct pcpu));
162 	pc->pc_mpidr = cp15_mpidr_get() & 0xFFFFFF;
163 	dpcpu_init(dpcpu[cpu - 1], cpu);
164 #if defined(DDB)
165 	dbg_monitor_init_secondary();
166 #endif
167 	/* Signal our startup to BSP */
168 	atomic_add_rel_32(&mp_naps, 1);
169 
170 	/* Spin until the BSP releases the APs */
171 	while (!atomic_load_acq_int(&aps_ready)) {
172 #if __ARM_ARCH >= 7
173 		__asm __volatile("wfe");
174 #endif
175 	}
176 
177 	/* Initialize curthread */
178 	KASSERT(PCPU_GET(idlethread) != NULL, ("no idle thread"));
179 	pc->pc_curthread = pc->pc_idlethread;
180 	pc->pc_curpcb = pc->pc_idlethread->td_pcb;
181 	set_curthread(pc->pc_idlethread);
182 	schedinit_ap();
183 #ifdef VFP
184 	vfp_init();
185 #endif
186 
187 	/* Configure the interrupt controller */
188 	intr_pic_init_secondary();
189 
190 	/* Apply possible BP hardening */
191 	cpuinfo_init_bp_hardening();
192 
193 	mtx_lock_spin(&ap_boot_mtx);
194 
195 	atomic_add_rel_32(&smp_cpus, 1);
196 
197 	if (smp_cpus == mp_ncpus) {
198 		/* enable IPI's, tlb shootdown, freezes etc */
199 		atomic_store_rel_int(&smp_started, 1);
200 	}
201 
202 	mtx_unlock_spin(&ap_boot_mtx);
203 
204 	loop_counter = 0;
205 	while (smp_started == 0) {
206 		DELAY(100);
207 		loop_counter++;
208 		if (loop_counter == 1000)
209 			CTR0(KTR_SMP, "AP still wait for smp_started");
210 	}
211 	/* Start per-CPU event timers. */
212 	cpu_initclocks_ap();
213 
214 	CTR0(KTR_SMP, "go into scheduler");
215 
216 	/* Enter the scheduler */
217 	sched_ap_entry();
218 
219 	panic("scheduler returned us to %s", __func__);
220 	/* NOTREACHED */
221 }
222 
223 static void
224 ipi_rendezvous(void *dummy __unused)
225 {
226 
227 	CTR0(KTR_SMP, "IPI_RENDEZVOUS");
228 	smp_rendezvous_action();
229 }
230 
231 static void
232 ipi_ast(void *dummy __unused)
233 {
234 
235 	CTR0(KTR_SMP, "IPI_AST");
236 }
237 
238 static void
239 ipi_stop(void *dummy __unused)
240 {
241 	u_int cpu;
242 
243 	/*
244 	 * IPI_STOP_HARD is mapped to IPI_STOP.
245 	 */
246 	CTR0(KTR_SMP, "IPI_STOP or IPI_STOP_HARD");
247 
248 	cpu = PCPU_GET(cpuid);
249 	savectx(&stoppcbs[cpu]);
250 
251 	/*
252 	 * CPUs are stopped when entering the debugger and at
253 	 * system shutdown, both events which can precede a
254 	 * panic dump.  For the dump to be correct, all caches
255 	 * must be flushed and invalidated, but on ARM there's
256 	 * no way to broadcast a wbinv_all to other cores.
257 	 * Instead, we have each core do the local wbinv_all as
258 	 * part of stopping the core.  The core requesting the
259 	 * stop will do the l2 cache flush after all other cores
260 	 * have done their l1 flushes and stopped.
261 	 */
262 	dcache_wbinv_poc_all();
263 
264 	/* Indicate we are stopped */
265 	CPU_SET_ATOMIC(cpu, &stopped_cpus);
266 
267 	/* Wait for restart */
268 	while (!CPU_ISSET(cpu, &started_cpus))
269 		cpu_spinwait();
270 
271 	CPU_CLR_ATOMIC(cpu, &started_cpus);
272 	CPU_CLR_ATOMIC(cpu, &stopped_cpus);
273 #ifdef DDB
274 	dbg_resume_dbreg();
275 #endif
276 	CTR0(KTR_SMP, "IPI_STOP (restart)");
277 }
278 
279 static void
280 ipi_preempt(void *arg)
281 {
282 
283 	CTR1(KTR_SMP, "%s: IPI_PREEMPT", __func__);
284 	sched_preempt(curthread);
285 }
286 
287 static void
288 ipi_hardclock(void *arg)
289 {
290 
291 	CTR1(KTR_SMP, "%s: IPI_HARDCLOCK", __func__);
292 	hardclockintr();
293 }
294 
295 static void
296 release_aps(void *dummy __unused)
297 {
298 	uint32_t loop_counter;
299 
300 	if (mp_ncpus == 1)
301 		return;
302 
303 	intr_pic_ipi_setup(IPI_RENDEZVOUS, "rendezvous", ipi_rendezvous, NULL);
304 	intr_pic_ipi_setup(IPI_AST, "ast", ipi_ast, NULL);
305 	intr_pic_ipi_setup(IPI_STOP, "stop", ipi_stop, NULL);
306 	intr_pic_ipi_setup(IPI_PREEMPT, "preempt", ipi_preempt, NULL);
307 	intr_pic_ipi_setup(IPI_HARDCLOCK, "hardclock", ipi_hardclock, NULL);
308 
309 	atomic_store_rel_int(&aps_ready, 1);
310 	/* Wake the other threads up */
311 	dsb();
312 	sev();
313 
314 	printf("Release APs\n");
315 
316 	for (loop_counter = 0; loop_counter < 2000; loop_counter++) {
317 		if (smp_started)
318 			return;
319 		DELAY(1000);
320 	}
321 	printf("AP's not started\n");
322 }
323 
324 SYSINIT(start_aps, SI_SUB_SMP, SI_ORDER_FIRST, release_aps, NULL);
325 
326 struct cpu_group *
327 cpu_topo(void)
328 {
329 
330 	return (smp_topo_1level(CG_SHARE_L2, mp_ncpus, 0));
331 }
332 
333 void
334 cpu_mp_setmaxid(void)
335 {
336 
337 	platform_mp_setmaxid();
338 }
339 
340 /* Sending IPI */
341 void
342 ipi_all_but_self(u_int ipi)
343 {
344 	cpuset_t other_cpus;
345 
346 	other_cpus = all_cpus;
347 	CPU_CLR(PCPU_GET(cpuid), &other_cpus);
348 	CTR2(KTR_SMP, "%s: ipi: %x", __func__, ipi);
349 	intr_ipi_send(other_cpus, ipi);
350 }
351 
352 void
353 ipi_cpu(int cpu, u_int ipi)
354 {
355 	cpuset_t cpus;
356 
357 	CPU_ZERO(&cpus);
358 	CPU_SET(cpu, &cpus);
359 
360 	CTR3(KTR_SMP, "%s: cpu: %d, ipi: %x", __func__, cpu, ipi);
361 	intr_ipi_send(cpus, ipi);
362 }
363 
364 void
365 ipi_selected(cpuset_t cpus, u_int ipi)
366 {
367 
368 	CTR2(KTR_SMP, "%s: ipi: %x", __func__, ipi);
369 	intr_ipi_send(cpus, ipi);
370 }
371