mp_machdep.c revision 183060 
1/*-
2 * Copyright (c) 2008 Marcel Moolenaar
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: head/sys/powerpc/powerpc/mp_machdep.c 183060 2008-09-16 01:05:54Z marcel $");
29
30#include <sys/param.h>
31#include <sys/systm.h>
32#include <sys/kernel.h>
33#include <sys/bus.h>
34#include <sys/pcpu.h>
35#include <sys/proc.h>
36#include <sys/sched.h>
37#include <sys/smp.h>
38
39#include <machine/bus.h>
40#include <machine/cpu.h>
41#include <machine/intr_machdep.h>
42#include <machine/smp.h>
43
44#include "pic_if.h"
45
46extern struct pcpu __pcpu[MAXCPU];
47
48volatile static int ap_awake;
49volatile static u_int ap_state;
50volatile static uint32_t ap_decr;
51
52int mp_ipi_test = 0;
53
54void
55machdep_ap_bootstrap(void)
56{
57
58	// __asm __volatile("mtspr 1023,%0" :: "r"(PCPU_GET(cpuid)));
59	__asm __volatile("mfspr %0,1023" : "=r"(pcpup->pc_pir));
60	pcpup->pc_awake = 1;
61
62	while (ap_state == 0)
63		;
64
65	__asm __volatile("mtdec %0" :: "r"(ap_decr));
66
67	ap_awake++;
68
69	/* Initialize curthread. */
70	PCPU_SET(curthread, PCPU_GET(idlethread));
71
72	mtmsr(mfmsr() | PSL_EE);
73	sched_throw(NULL);
74}
75
76struct cpu_group *
77cpu_topo(void)
78{
79
80	return (smp_topo_none());
81}
82
83void
84cpu_mp_setmaxid(void)
85{
86	struct cpuref cpuref;
87	int error;
88
89	mp_ncpus = 0;
90	error = powerpc_smp_first_cpu(&cpuref);
91	while (!error) {
92		mp_ncpus++;
93		error = powerpc_smp_next_cpu(&cpuref);
94	}
95	/* Sanity. */
96	if (mp_ncpus == 0)
97		mp_ncpus = 1;
98
99	/*
100	 * Set the largest cpuid we're going to use. This is necessary
101	 * for VM initialization.
102	 */
103	mp_maxid = min(mp_ncpus, MAXCPU) - 1;
104}
105
106int
107cpu_mp_probe(void)
108{
109
110	/*
111	 * We're not going to enable SMP if there's only 1 processor.
112	 */
113	return (mp_ncpus > 1);
114}
115
116void
117cpu_mp_start(void)
118{
119	struct cpuref bsp, cpu;
120	struct pcpu *pc;
121	int error;
122
123	error = powerpc_smp_get_bsp(&bsp);
124	KASSERT(error == 0, ("Don't know BSP"));
125	KASSERT(bsp.cr_cpuid == 0, ("%s: cpuid != 0", __func__));
126
127	error = powerpc_smp_first_cpu(&cpu);
128	while (!error) {
129		if (cpu.cr_cpuid >= MAXCPU) {
130			printf("SMP: cpu%d: skipped -- ID out of range\n",
131			    cpu.cr_cpuid);
132			goto next;
133		}
134		if (all_cpus & (1 << cpu.cr_cpuid)) {
135			printf("SMP: cpu%d: skipped - duplicate ID\n",
136			    cpu.cr_cpuid);
137			goto next;
138		}
139		if (cpu.cr_cpuid != bsp.cr_cpuid) {
140			pc = &__pcpu[cpu.cr_cpuid];
141			pcpu_init(pc, cpu.cr_cpuid, sizeof(*pc));
142		} else {
143			pc = pcpup;
144			pc->pc_cpuid = bsp.cr_cpuid;
145			pc->pc_bsp = 1;
146		}
147		pc->pc_cpumask = 1 << pc->pc_cpuid;
148		pc->pc_hwref = cpu.cr_hwref;
149		all_cpus |= pc->pc_cpumask;
150
151 next:
152		error = powerpc_smp_next_cpu(&cpu);
153	}
154}
155
156void
157cpu_mp_announce(void)
158{
159	struct pcpu *pc;
160	int i;
161
162	for (i = 0; i <= mp_maxid; i++) {
163		pc = pcpu_find(i);
164		if (pc == NULL)
165			continue;
166		printf("cpu%d: dev=%x", i, pc->pc_hwref);
167		if (pc->pc_bsp)
168			printf(" (BSP)");
169		printf("\n");
170	}
171}
172
173static void
174cpu_mp_unleash(void *dummy)
175{
176	struct pcpu *pc;
177	int cpus;
178
179	if (mp_ncpus <= 1)
180		return;
181
182	if (mp_ipi_test != 1) {
183		printf("SMP: ERROR: sending of a test IPI failed\n");
184		return;
185	}
186
187	cpus = 0;
188	smp_cpus = 0;
189	SLIST_FOREACH(pc, &cpuhead, pc_allcpu) {
190		cpus++;
191		pc->pc_other_cpus = all_cpus & ~pc->pc_cpumask;
192		if (!pc->pc_bsp) {
193			printf("Waking up CPU %d (dev=%x)\n", pc->pc_cpuid,
194			    pc->pc_hwref);
195			powerpc_smp_start_cpu(pc);
196		} else {
197			__asm __volatile("mfspr %0,1023" : "=r"(pc->pc_pir));
198			pc->pc_awake = 1;
199		}
200		if (pc->pc_awake)
201			smp_cpus++;
202	}
203
204	ap_awake = 1;
205	__asm __volatile("mfdec %0" : "=r"(ap_decr));
206	ap_state++;
207
208	while (ap_awake < smp_cpus)
209		;
210
211	if (smp_cpus != cpus || cpus != mp_ncpus) {
212		printf("SMP: %d CPUs found; %d CPUs usable; %d CPUs woken\n",
213			mp_ncpus, cpus, smp_cpus);
214	}
215
216	smp_active = 1;
217	smp_started = 1;
218}
219
220SYSINIT(start_aps, SI_SUB_SMP, SI_ORDER_FIRST, cpu_mp_unleash, NULL);
221
222static u_int ipi_msg_cnt[32];
223
224int
225powerpc_ipi_handler(void *arg)
226{
227	cpumask_t self;
228	uint32_t ipimask;
229	int msg;
230
231	ipimask = atomic_readandclear_32(&(pcpup->pc_ipimask));
232	if (ipimask == 0)
233		return (FILTER_STRAY);
234	while ((msg = ffs(ipimask) - 1) != -1) {
235		ipimask &= ~(1u << msg);
236		ipi_msg_cnt[msg]++;
237		switch (msg) {
238		case IPI_AST:
239			break;
240		case IPI_PREEMPT:
241			sched_preempt(curthread);
242			break;
243		case IPI_RENDEZVOUS:
244			smp_rendezvous_action();
245			break;
246		case IPI_STOP:
247			self = PCPU_GET(cpumask);
248			savectx(PCPU_GET(curpcb));
249			atomic_set_int(&stopped_cpus, self);
250			while ((started_cpus & self) == 0)
251				cpu_spinwait();
252			atomic_clear_int(&started_cpus, self);
253			atomic_clear_int(&stopped_cpus, self);
254			break;
255		case IPI_PPC_TEST:
256			mp_ipi_test++;
257			break;
258		}
259	}
260
261	return (FILTER_HANDLED);
262}
263
264static void
265ipi_send(struct pcpu *pc, int ipi)
266{
267
268	atomic_set_32(&pc->pc_ipimask, (1 << ipi));
269	PIC_IPI(pic, pc->pc_cpuid);
270}
271
272/* Send an IPI to a set of cpus. */
273void
274ipi_selected(cpumask_t cpus, int ipi)
275{
276	struct pcpu *pc;
277
278	SLIST_FOREACH(pc, &cpuhead, pc_allcpu) {
279		if (cpus & pc->pc_cpumask)
280			ipi_send(pc, ipi);
281	}
282}
283
284/* Send an IPI to all CPUs, including myself. */
285void
286ipi_all(int ipi)
287{
288	struct pcpu *pc;
289
290	SLIST_FOREACH(pc, &cpuhead, pc_allcpu) {
291		ipi_send(pc, ipi);
292	}
293}
294
295/* Send an IPI to all CPUs EXCEPT myself. */
296void
297ipi_all_but_self(int ipi)
298{
299	struct pcpu *pc;
300
301	SLIST_FOREACH(pc, &cpuhead, pc_allcpu) {
302		if (pc != pcpup)
303			ipi_send(pc, ipi);
304	}
305}
306
307/* Send an IPI to myself. */
308void
309ipi_self(int ipi)
310{
311
312	ipi_send(pcpup, ipi);
313}
314