4 * Written by Cort Dougan (cort@cs.nmt.edu) borrowing a great
5 * deal of code from the sparc and intel versions.
7 * Copyright (C) 1999 Cort Dougan <cort@cs.nmt.edu>
9 * PowerPC-64 Support added by Dave Engebretsen, Peter Bergner, and
10 * Mike Corrigan {engebret|bergner|mikec}@us.ibm.com
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * as published by the Free Software Foundation; either version
15 * 2 of the License, or (at your option) any later version.
20 #include <linux/kernel.h>
21 #include <linux/module.h>
22 #include <linux/sched.h>
23 #include <linux/smp.h>
24 #include <linux/interrupt.h>
25 #include <linux/delay.h>
26 #include <linux/init.h>
27 #include <linux/spinlock.h>
28 #include <linux/cache.h>
29 #include <linux/err.h>
30 #include <linux/sysdev.h>
31 #include <linux/cpu.h>
32 #include <linux/notifier.h>
33 #include <linux/topology.h>
35 #include <asm/ptrace.h>
36 #include <asm/atomic.h>
39 #include <asm/pgtable.h>
43 #include <asm/machdep.h>
44 #include <asm/cputhreads.h>
45 #include <asm/cputable.h>
46 #include <asm/system.h>
48 #include <asm/vdso_datapage.h>
55 #define DBG(fmt...) udbg_printf(fmt)
60 struct thread_info *secondary_ti;
62 cpumask_t cpu_possible_map = CPU_MASK_NONE;
63 cpumask_t cpu_online_map = CPU_MASK_NONE;
64 DEFINE_PER_CPU(cpumask_t, cpu_sibling_map) = CPU_MASK_NONE;
65 DEFINE_PER_CPU(cpumask_t, cpu_core_map) = CPU_MASK_NONE;
67 EXPORT_SYMBOL(cpu_online_map);
68 EXPORT_SYMBOL(cpu_possible_map);
69 EXPORT_PER_CPU_SYMBOL(cpu_sibling_map);
70 EXPORT_PER_CPU_SYMBOL(cpu_core_map);
72 /* SMP operations for this machine */
73 struct smp_ops_t *smp_ops;
75 static volatile unsigned int cpu_callin_map[NR_CPUS];
77 int smt_enabled_at_boot = 1;
79 static void (*crash_ipi_function_ptr)(struct pt_regs *) = NULL;
82 void __devinit smp_generic_kick_cpu(int nr)
84 BUG_ON(nr < 0 || nr >= NR_CPUS);
87 * The processor is currently spinning, waiting for the
88 * cpu_start field to become non-zero After we set cpu_start,
89 * the processor will continue on to secondary_start
91 paca[nr].cpu_start = 1;
96 void smp_message_recv(int msg)
99 case PPC_MSG_CALL_FUNCTION:
100 generic_smp_call_function_interrupt();
102 case PPC_MSG_RESCHEDULE:
103 /* we notice need_resched on exit */
105 case PPC_MSG_CALL_FUNC_SINGLE:
106 generic_smp_call_function_single_interrupt();
108 case PPC_MSG_DEBUGGER_BREAK:
109 if (crash_ipi_function_ptr) {
110 crash_ipi_function_ptr(get_irq_regs());
113 #ifdef CONFIG_DEBUGGER
114 debugger_ipi(get_irq_regs());
116 #endif /* CONFIG_DEBUGGER */
119 printk("SMP %d: smp_message_recv(): unknown msg %d\n",
120 smp_processor_id(), msg);
125 static irqreturn_t call_function_action(int irq, void *data)
127 generic_smp_call_function_interrupt();
131 static irqreturn_t reschedule_action(int irq, void *data)
133 /* we just need the return path side effect of checking need_resched */
137 static irqreturn_t call_function_single_action(int irq, void *data)
139 generic_smp_call_function_single_interrupt();
143 static irqreturn_t debug_ipi_action(int irq, void *data)
145 smp_message_recv(PPC_MSG_DEBUGGER_BREAK);
149 static irq_handler_t smp_ipi_action[] = {
150 [PPC_MSG_CALL_FUNCTION] = call_function_action,
151 [PPC_MSG_RESCHEDULE] = reschedule_action,
152 [PPC_MSG_CALL_FUNC_SINGLE] = call_function_single_action,
153 [PPC_MSG_DEBUGGER_BREAK] = debug_ipi_action,
156 const char *smp_ipi_name[] = {
157 [PPC_MSG_CALL_FUNCTION] = "ipi call function",
158 [PPC_MSG_RESCHEDULE] = "ipi reschedule",
159 [PPC_MSG_CALL_FUNC_SINGLE] = "ipi call function single",
160 [PPC_MSG_DEBUGGER_BREAK] = "ipi debugger",
163 /* optional function to request ipi, for controllers with >= 4 ipis */
164 int smp_request_message_ipi(int virq, int msg)
168 if (msg < 0 || msg > PPC_MSG_DEBUGGER_BREAK) {
171 #if !defined(CONFIG_DEBUGGER) && !defined(CONFIG_KEXEC)
172 if (msg == PPC_MSG_DEBUGGER_BREAK) {
176 err = request_irq(virq, smp_ipi_action[msg], IRQF_DISABLED|IRQF_PERCPU,
177 smp_ipi_name[msg], 0);
178 WARN(err < 0, "unable to request_irq %d for %s (rc %d)\n",
179 virq, smp_ipi_name[msg], err);
184 void smp_send_reschedule(int cpu)
187 smp_ops->message_pass(cpu, PPC_MSG_RESCHEDULE);
190 void arch_send_call_function_single_ipi(int cpu)
192 smp_ops->message_pass(cpu, PPC_MSG_CALL_FUNC_SINGLE);
195 void arch_send_call_function_ipi(cpumask_t mask)
199 for_each_cpu_mask(cpu, mask)
200 smp_ops->message_pass(cpu, PPC_MSG_CALL_FUNCTION);
203 #ifdef CONFIG_DEBUGGER
204 void smp_send_debugger_break(int cpu)
207 smp_ops->message_pass(cpu, PPC_MSG_DEBUGGER_BREAK);
212 void crash_send_ipi(void (*crash_ipi_callback)(struct pt_regs *))
214 crash_ipi_function_ptr = crash_ipi_callback;
215 if (crash_ipi_callback && smp_ops) {
217 smp_ops->message_pass(MSG_ALL_BUT_SELF, PPC_MSG_DEBUGGER_BREAK);
222 static void stop_this_cpu(void *dummy)
229 void smp_send_stop(void)
231 smp_call_function(stop_this_cpu, NULL, 0);
234 struct thread_info *current_set[NR_CPUS];
236 static void __devinit smp_store_cpu_info(int id)
238 per_cpu(pvr, id) = mfspr(SPRN_PVR);
241 static void __init smp_create_idle(unsigned int cpu)
243 struct task_struct *p;
245 /* create a process for the processor */
248 panic("failed fork for CPU %u: %li", cpu, PTR_ERR(p));
250 paca[cpu].__current = p;
251 paca[cpu].kstack = (unsigned long) task_thread_info(p)
252 + THREAD_SIZE - STACK_FRAME_OVERHEAD;
254 current_set[cpu] = task_thread_info(p);
255 task_thread_info(p)->cpu = cpu;
258 void __init smp_prepare_cpus(unsigned int max_cpus)
262 DBG("smp_prepare_cpus\n");
265 * setup_cpu may need to be called on the boot cpu. We havent
266 * spun any cpus up but lets be paranoid.
268 BUG_ON(boot_cpuid != smp_processor_id());
271 smp_store_cpu_info(boot_cpuid);
272 cpu_callin_map[boot_cpuid] = 1;
275 max_cpus = smp_ops->probe();
279 smp_space_timers(max_cpus);
281 for_each_possible_cpu(cpu)
282 if (cpu != boot_cpuid)
283 smp_create_idle(cpu);
286 void __devinit smp_prepare_boot_cpu(void)
288 BUG_ON(smp_processor_id() != boot_cpuid);
290 cpu_set(boot_cpuid, cpu_online_map);
291 cpu_set(boot_cpuid, per_cpu(cpu_sibling_map, boot_cpuid));
292 cpu_set(boot_cpuid, per_cpu(cpu_core_map, boot_cpuid));
294 paca[boot_cpuid].__current = current;
296 current_set[boot_cpuid] = task_thread_info(current);
299 #ifdef CONFIG_HOTPLUG_CPU
300 /* State of each CPU during hotplug phases */
301 DEFINE_PER_CPU(int, cpu_state) = { 0 };
303 int generic_cpu_disable(void)
305 unsigned int cpu = smp_processor_id();
307 if (cpu == boot_cpuid)
310 cpu_clear(cpu, cpu_online_map);
312 vdso_data->processorCount--;
313 fixup_irqs(cpu_online_map);
318 int generic_cpu_enable(unsigned int cpu)
320 /* Do the normal bootup if we haven't
321 * already bootstrapped. */
322 if (system_state != SYSTEM_RUNNING)
325 /* get the target out of it's holding state */
326 per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
329 while (!cpu_online(cpu))
333 fixup_irqs(cpu_online_map);
334 /* counter the irq disable in fixup_irqs */
340 void generic_cpu_die(unsigned int cpu)
344 for (i = 0; i < 100; i++) {
346 if (per_cpu(cpu_state, cpu) == CPU_DEAD)
350 printk(KERN_ERR "CPU%d didn't die...\n", cpu);
353 void generic_mach_cpu_die(void)
358 cpu = smp_processor_id();
359 printk(KERN_DEBUG "CPU%d offline\n", cpu);
360 __get_cpu_var(cpu_state) = CPU_DEAD;
362 while (__get_cpu_var(cpu_state) != CPU_UP_PREPARE)
364 cpu_set(cpu, cpu_online_map);
369 static int __devinit cpu_enable(unsigned int cpu)
371 if (smp_ops && smp_ops->cpu_enable)
372 return smp_ops->cpu_enable(cpu);
377 int __cpuinit __cpu_up(unsigned int cpu)
381 secondary_ti = current_set[cpu];
382 if (!cpu_enable(cpu))
385 if (smp_ops == NULL ||
386 (smp_ops->cpu_bootable && !smp_ops->cpu_bootable(cpu)))
389 /* Make sure callin-map entry is 0 (can be leftover a CPU
392 cpu_callin_map[cpu] = 0;
394 /* The information for processor bringup must
395 * be written out to main store before we release
401 DBG("smp: kicking cpu %d\n", cpu);
402 smp_ops->kick_cpu(cpu);
405 * wait to see if the cpu made a callin (is actually up).
406 * use this value that I found through experimentation.
409 if (system_state < SYSTEM_RUNNING)
410 for (c = 50000; c && !cpu_callin_map[cpu]; c--)
412 #ifdef CONFIG_HOTPLUG_CPU
415 * CPUs can take much longer to come up in the
416 * hotplug case. Wait five seconds.
418 for (c = 25; c && !cpu_callin_map[cpu]; c--) {
423 if (!cpu_callin_map[cpu]) {
424 printk("Processor %u is stuck.\n", cpu);
428 printk("Processor %u found.\n", cpu);
430 if (smp_ops->give_timebase)
431 smp_ops->give_timebase();
433 /* Wait until cpu puts itself in the online map */
434 while (!cpu_online(cpu))
440 /* Return the value of the reg property corresponding to the given
443 int cpu_to_core_id(int cpu)
445 struct device_node *np;
449 np = of_get_cpu_node(cpu, NULL);
453 reg = of_get_property(np, "reg", NULL);
463 /* Must be called when no change can occur to cpu_present_map,
464 * i.e. during cpu online or offline.
466 static struct device_node *cpu_to_l2cache(int cpu)
468 struct device_node *np;
469 struct device_node *cache;
471 if (!cpu_present(cpu))
474 np = of_get_cpu_node(cpu, NULL);
478 cache = of_find_next_cache_node(np);
485 /* Activate a secondary processor. */
486 int __devinit start_secondary(void *unused)
488 unsigned int cpu = smp_processor_id();
489 struct device_node *l2_cache;
492 atomic_inc(&init_mm.mm_count);
493 current->active_mm = &init_mm;
495 smp_store_cpu_info(cpu);
496 set_dec(tb_ticks_per_jiffy);
498 cpu_callin_map[cpu] = 1;
500 smp_ops->setup_cpu(cpu);
501 if (smp_ops->take_timebase)
502 smp_ops->take_timebase();
504 if (system_state > SYSTEM_BOOTING)
507 secondary_cpu_time_init();
510 notify_cpu_starting(cpu);
511 cpu_set(cpu, cpu_online_map);
512 /* Update sibling maps */
513 base = cpu_first_thread_in_core(cpu);
514 for (i = 0; i < threads_per_core; i++) {
515 if (cpu_is_offline(base + i))
517 cpu_set(cpu, per_cpu(cpu_sibling_map, base + i));
518 cpu_set(base + i, per_cpu(cpu_sibling_map, cpu));
520 /* cpu_core_map should be a superset of
521 * cpu_sibling_map even if we don't have cache
522 * information, so update the former here, too.
524 cpu_set(cpu, per_cpu(cpu_core_map, base +i));
525 cpu_set(base + i, per_cpu(cpu_core_map, cpu));
527 l2_cache = cpu_to_l2cache(cpu);
528 for_each_online_cpu(i) {
529 struct device_node *np = cpu_to_l2cache(i);
532 if (np == l2_cache) {
533 cpu_set(cpu, per_cpu(cpu_core_map, i));
534 cpu_set(i, per_cpu(cpu_core_map, cpu));
538 of_node_put(l2_cache);
547 int setup_profiling_timer(unsigned int multiplier)
552 void __init smp_cpus_done(unsigned int max_cpus)
556 /* We want the setup_cpu() here to be called from CPU 0, but our
557 * init thread may have been "borrowed" by another CPU in the meantime
558 * se we pin us down to CPU 0 for a short while
560 old_mask = current->cpus_allowed;
561 set_cpus_allowed(current, cpumask_of_cpu(boot_cpuid));
564 smp_ops->setup_cpu(boot_cpuid);
566 set_cpus_allowed(current, old_mask);
568 snapshot_timebases();
570 dump_numa_cpu_topology();
573 #ifdef CONFIG_HOTPLUG_CPU
574 int __cpu_disable(void)
576 struct device_node *l2_cache;
577 int cpu = smp_processor_id();
581 if (!smp_ops->cpu_disable)
584 err = smp_ops->cpu_disable();
588 /* Update sibling maps */
589 base = cpu_first_thread_in_core(cpu);
590 for (i = 0; i < threads_per_core; i++) {
591 cpu_clear(cpu, per_cpu(cpu_sibling_map, base + i));
592 cpu_clear(base + i, per_cpu(cpu_sibling_map, cpu));
593 cpu_clear(cpu, per_cpu(cpu_core_map, base +i));
594 cpu_clear(base + i, per_cpu(cpu_core_map, cpu));
597 l2_cache = cpu_to_l2cache(cpu);
598 for_each_present_cpu(i) {
599 struct device_node *np = cpu_to_l2cache(i);
602 if (np == l2_cache) {
603 cpu_clear(cpu, per_cpu(cpu_core_map, i));
604 cpu_clear(i, per_cpu(cpu_core_map, cpu));
608 of_node_put(l2_cache);
614 void __cpu_die(unsigned int cpu)
616 if (smp_ops->cpu_die)
617 smp_ops->cpu_die(cpu);