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 int smp_hw_index[NR_CPUS];
61 struct thread_info *secondary_ti;
63 cpumask_t cpu_possible_map = CPU_MASK_NONE;
64 cpumask_t cpu_online_map = CPU_MASK_NONE;
65 DEFINE_PER_CPU(cpumask_t, cpu_sibling_map) = CPU_MASK_NONE;
66 DEFINE_PER_CPU(cpumask_t, cpu_core_map) = CPU_MASK_NONE;
68 EXPORT_SYMBOL(cpu_online_map);
69 EXPORT_SYMBOL(cpu_possible_map);
70 EXPORT_PER_CPU_SYMBOL(cpu_sibling_map);
71 EXPORT_PER_CPU_SYMBOL(cpu_core_map);
73 /* SMP operations for this machine */
74 struct smp_ops_t *smp_ops;
76 static volatile unsigned int cpu_callin_map[NR_CPUS];
78 int smt_enabled_at_boot = 1;
80 static void (*crash_ipi_function_ptr)(struct pt_regs *) = NULL;
83 void __devinit smp_generic_kick_cpu(int nr)
85 BUG_ON(nr < 0 || nr >= NR_CPUS);
88 * The processor is currently spinning, waiting for the
89 * cpu_start field to become non-zero After we set cpu_start,
90 * the processor will continue on to secondary_start
92 paca[nr].cpu_start = 1;
97 void smp_message_recv(int msg)
100 case PPC_MSG_CALL_FUNCTION:
101 generic_smp_call_function_interrupt();
103 case PPC_MSG_RESCHEDULE:
104 /* we notice need_resched on exit */
106 case PPC_MSG_CALL_FUNC_SINGLE:
107 generic_smp_call_function_single_interrupt();
109 case PPC_MSG_DEBUGGER_BREAK:
110 if (crash_ipi_function_ptr) {
111 crash_ipi_function_ptr(get_irq_regs());
114 #ifdef CONFIG_DEBUGGER
115 debugger_ipi(get_irq_regs());
117 #endif /* CONFIG_DEBUGGER */
120 printk("SMP %d: smp_message_recv(): unknown msg %d\n",
121 smp_processor_id(), msg);
126 static irqreturn_t call_function_action(int irq, void *data)
128 generic_smp_call_function_interrupt();
132 static irqreturn_t reschedule_action(int irq, void *data)
134 /* we just need the return path side effect of checking need_resched */
138 static irqreturn_t call_function_single_action(int irq, void *data)
140 generic_smp_call_function_single_interrupt();
144 static irqreturn_t debug_ipi_action(int irq, void *data)
146 smp_message_recv(PPC_MSG_DEBUGGER_BREAK);
150 static irq_handler_t smp_ipi_action[] = {
151 [PPC_MSG_CALL_FUNCTION] = call_function_action,
152 [PPC_MSG_RESCHEDULE] = reschedule_action,
153 [PPC_MSG_CALL_FUNC_SINGLE] = call_function_single_action,
154 [PPC_MSG_DEBUGGER_BREAK] = debug_ipi_action,
157 const char *smp_ipi_name[] = {
158 [PPC_MSG_CALL_FUNCTION] = "ipi call function",
159 [PPC_MSG_RESCHEDULE] = "ipi reschedule",
160 [PPC_MSG_CALL_FUNC_SINGLE] = "ipi call function single",
161 [PPC_MSG_DEBUGGER_BREAK] = "ipi debugger",
164 /* optional function to request ipi, for controllers with >= 4 ipis */
165 int smp_request_message_ipi(int virq, int msg)
169 if (msg < 0 || msg > PPC_MSG_DEBUGGER_BREAK) {
172 #if !defined(CONFIG_DEBUGGER) && !defined(CONFIG_KEXEC)
173 if (msg == PPC_MSG_DEBUGGER_BREAK) {
177 err = request_irq(virq, smp_ipi_action[msg], IRQF_DISABLED|IRQF_PERCPU,
178 smp_ipi_name[msg], 0);
179 WARN(err < 0, "unable to request_irq %d for %s (rc %d)\n",
180 virq, smp_ipi_name[msg], err);
185 void smp_send_reschedule(int cpu)
188 smp_ops->message_pass(cpu, PPC_MSG_RESCHEDULE);
191 void arch_send_call_function_single_ipi(int cpu)
193 smp_ops->message_pass(cpu, PPC_MSG_CALL_FUNC_SINGLE);
196 void arch_send_call_function_ipi(cpumask_t mask)
200 for_each_cpu_mask(cpu, mask)
201 smp_ops->message_pass(cpu, PPC_MSG_CALL_FUNCTION);
204 #ifdef CONFIG_DEBUGGER
205 void smp_send_debugger_break(int cpu)
208 smp_ops->message_pass(cpu, PPC_MSG_DEBUGGER_BREAK);
213 void crash_send_ipi(void (*crash_ipi_callback)(struct pt_regs *))
215 crash_ipi_function_ptr = crash_ipi_callback;
216 if (crash_ipi_callback && smp_ops) {
218 smp_ops->message_pass(MSG_ALL_BUT_SELF, PPC_MSG_DEBUGGER_BREAK);
223 static void stop_this_cpu(void *dummy)
230 void smp_send_stop(void)
232 smp_call_function(stop_this_cpu, NULL, 0);
235 struct thread_info *current_set[NR_CPUS];
237 static void __devinit smp_store_cpu_info(int id)
239 per_cpu(pvr, id) = mfspr(SPRN_PVR);
242 static void __init smp_create_idle(unsigned int cpu)
244 struct task_struct *p;
246 /* create a process for the processor */
249 panic("failed fork for CPU %u: %li", cpu, PTR_ERR(p));
251 paca[cpu].__current = p;
252 paca[cpu].kstack = (unsigned long) task_thread_info(p)
253 + THREAD_SIZE - STACK_FRAME_OVERHEAD;
255 current_set[cpu] = task_thread_info(p);
256 task_thread_info(p)->cpu = cpu;
259 void __init smp_prepare_cpus(unsigned int max_cpus)
263 DBG("smp_prepare_cpus\n");
266 * setup_cpu may need to be called on the boot cpu. We havent
267 * spun any cpus up but lets be paranoid.
269 BUG_ON(boot_cpuid != smp_processor_id());
272 smp_store_cpu_info(boot_cpuid);
273 cpu_callin_map[boot_cpuid] = 1;
276 max_cpus = smp_ops->probe();
280 smp_space_timers(max_cpus);
282 for_each_possible_cpu(cpu)
283 if (cpu != boot_cpuid)
284 smp_create_idle(cpu);
287 void __devinit smp_prepare_boot_cpu(void)
289 BUG_ON(smp_processor_id() != boot_cpuid);
291 cpu_set(boot_cpuid, cpu_online_map);
292 cpu_set(boot_cpuid, per_cpu(cpu_sibling_map, boot_cpuid));
293 cpu_set(boot_cpuid, per_cpu(cpu_core_map, boot_cpuid));
295 paca[boot_cpuid].__current = current;
297 current_set[boot_cpuid] = task_thread_info(current);
300 #ifdef CONFIG_HOTPLUG_CPU
301 /* State of each CPU during hotplug phases */
302 DEFINE_PER_CPU(int, cpu_state) = { 0 };
304 int generic_cpu_disable(void)
306 unsigned int cpu = smp_processor_id();
308 if (cpu == boot_cpuid)
311 cpu_clear(cpu, cpu_online_map);
313 vdso_data->processorCount--;
314 fixup_irqs(cpu_online_map);
319 int generic_cpu_enable(unsigned int cpu)
321 /* Do the normal bootup if we haven't
322 * already bootstrapped. */
323 if (system_state != SYSTEM_RUNNING)
326 /* get the target out of it's holding state */
327 per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
330 while (!cpu_online(cpu))
334 fixup_irqs(cpu_online_map);
335 /* counter the irq disable in fixup_irqs */
341 void generic_cpu_die(unsigned int cpu)
345 for (i = 0; i < 100; i++) {
347 if (per_cpu(cpu_state, cpu) == CPU_DEAD)
351 printk(KERN_ERR "CPU%d didn't die...\n", cpu);
354 void generic_mach_cpu_die(void)
359 cpu = smp_processor_id();
360 printk(KERN_DEBUG "CPU%d offline\n", cpu);
361 __get_cpu_var(cpu_state) = CPU_DEAD;
363 while (__get_cpu_var(cpu_state) != CPU_UP_PREPARE)
365 cpu_set(cpu, cpu_online_map);
370 static int __devinit cpu_enable(unsigned int cpu)
372 if (smp_ops && smp_ops->cpu_enable)
373 return smp_ops->cpu_enable(cpu);
378 int __cpuinit __cpu_up(unsigned int cpu)
382 secondary_ti = current_set[cpu];
383 if (!cpu_enable(cpu))
386 if (smp_ops == NULL ||
387 (smp_ops->cpu_bootable && !smp_ops->cpu_bootable(cpu)))
390 /* Make sure callin-map entry is 0 (can be leftover a CPU
393 cpu_callin_map[cpu] = 0;
395 /* The information for processor bringup must
396 * be written out to main store before we release
402 DBG("smp: kicking cpu %d\n", cpu);
403 smp_ops->kick_cpu(cpu);
406 * wait to see if the cpu made a callin (is actually up).
407 * use this value that I found through experimentation.
410 if (system_state < SYSTEM_RUNNING)
411 for (c = 50000; c && !cpu_callin_map[cpu]; c--)
413 #ifdef CONFIG_HOTPLUG_CPU
416 * CPUs can take much longer to come up in the
417 * hotplug case. Wait five seconds.
419 for (c = 25; c && !cpu_callin_map[cpu]; c--) {
424 if (!cpu_callin_map[cpu]) {
425 printk("Processor %u is stuck.\n", cpu);
429 printk("Processor %u found.\n", cpu);
431 if (smp_ops->give_timebase)
432 smp_ops->give_timebase();
434 /* Wait until cpu puts itself in the online map */
435 while (!cpu_online(cpu))
441 /* Return the value of the reg property corresponding to the given
444 int cpu_to_core_id(int cpu)
446 struct device_node *np;
450 np = of_get_cpu_node(cpu, NULL);
454 reg = of_get_property(np, "reg", NULL);
464 /* Must be called when no change can occur to cpu_present_map,
465 * i.e. during cpu online or offline.
467 static struct device_node *cpu_to_l2cache(int cpu)
469 struct device_node *np;
473 if (!cpu_present(cpu))
476 np = of_get_cpu_node(cpu, NULL);
480 php = of_get_property(np, "l2-cache", NULL);
486 return of_find_node_by_phandle(ph);
489 /* Activate a secondary processor. */
490 int __devinit start_secondary(void *unused)
492 unsigned int cpu = smp_processor_id();
493 struct device_node *l2_cache;
496 atomic_inc(&init_mm.mm_count);
497 current->active_mm = &init_mm;
499 smp_store_cpu_info(cpu);
500 set_dec(tb_ticks_per_jiffy);
502 cpu_callin_map[cpu] = 1;
504 smp_ops->setup_cpu(cpu);
505 if (smp_ops->take_timebase)
506 smp_ops->take_timebase();
508 if (system_state > SYSTEM_BOOTING)
511 secondary_cpu_time_init();
514 notify_cpu_starting(cpu);
515 cpu_set(cpu, cpu_online_map);
516 /* Update sibling maps */
517 base = cpu_first_thread_in_core(cpu);
518 for (i = 0; i < threads_per_core; i++) {
519 if (cpu_is_offline(base + i))
521 cpu_set(cpu, per_cpu(cpu_sibling_map, base + i));
522 cpu_set(base + i, per_cpu(cpu_sibling_map, cpu));
524 /* cpu_core_map should be a superset of
525 * cpu_sibling_map even if we don't have cache
526 * information, so update the former here, too.
528 cpu_set(cpu, per_cpu(cpu_core_map, base +i));
529 cpu_set(base + i, per_cpu(cpu_core_map, cpu));
531 l2_cache = cpu_to_l2cache(cpu);
532 for_each_online_cpu(i) {
533 struct device_node *np = cpu_to_l2cache(i);
536 if (np == l2_cache) {
537 cpu_set(cpu, per_cpu(cpu_core_map, i));
538 cpu_set(i, per_cpu(cpu_core_map, cpu));
542 of_node_put(l2_cache);
551 int setup_profiling_timer(unsigned int multiplier)
556 void __init smp_cpus_done(unsigned int max_cpus)
560 /* We want the setup_cpu() here to be called from CPU 0, but our
561 * init thread may have been "borrowed" by another CPU in the meantime
562 * se we pin us down to CPU 0 for a short while
564 old_mask = current->cpus_allowed;
565 set_cpus_allowed(current, cpumask_of_cpu(boot_cpuid));
568 smp_ops->setup_cpu(boot_cpuid);
570 set_cpus_allowed(current, old_mask);
572 snapshot_timebases();
574 dump_numa_cpu_topology();
577 #ifdef CONFIG_HOTPLUG_CPU
578 int __cpu_disable(void)
580 struct device_node *l2_cache;
581 int cpu = smp_processor_id();
585 if (!smp_ops->cpu_disable)
588 err = smp_ops->cpu_disable();
592 /* Update sibling maps */
593 base = cpu_first_thread_in_core(cpu);
594 for (i = 0; i < threads_per_core; i++) {
595 cpu_clear(cpu, per_cpu(cpu_sibling_map, base + i));
596 cpu_clear(base + i, per_cpu(cpu_sibling_map, cpu));
597 cpu_clear(cpu, per_cpu(cpu_core_map, base +i));
598 cpu_clear(base + i, per_cpu(cpu_core_map, cpu));
601 l2_cache = cpu_to_l2cache(cpu);
602 for_each_present_cpu(i) {
603 struct device_node *np = cpu_to_l2cache(i);
606 if (np == l2_cache) {
607 cpu_clear(cpu, per_cpu(cpu_core_map, i));
608 cpu_clear(i, per_cpu(cpu_core_map, cpu));
612 of_node_put(l2_cache);
618 void __cpu_die(unsigned int cpu)
620 if (smp_ops->cpu_die)
621 smp_ops->cpu_die(cpu);