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 /* XXX Do we have to do this? */
107 case PPC_MSG_CALL_FUNC_SINGLE:
108 generic_smp_call_function_single_interrupt();
110 case PPC_MSG_DEBUGGER_BREAK:
111 if (crash_ipi_function_ptr) {
112 crash_ipi_function_ptr(get_irq_regs());
115 #ifdef CONFIG_DEBUGGER
116 debugger_ipi(get_irq_regs());
118 #endif /* CONFIG_DEBUGGER */
121 printk("SMP %d: smp_message_recv(): unknown msg %d\n",
122 smp_processor_id(), msg);
127 void smp_send_reschedule(int cpu)
130 smp_ops->message_pass(cpu, PPC_MSG_RESCHEDULE);
133 void arch_send_call_function_single_ipi(int cpu)
135 smp_ops->message_pass(cpu, PPC_MSG_CALL_FUNC_SINGLE);
138 void arch_send_call_function_ipi(cpumask_t mask)
142 for_each_cpu_mask(cpu, mask)
143 smp_ops->message_pass(cpu, PPC_MSG_CALL_FUNCTION);
146 #ifdef CONFIG_DEBUGGER
147 void smp_send_debugger_break(int cpu)
150 smp_ops->message_pass(cpu, PPC_MSG_DEBUGGER_BREAK);
155 void crash_send_ipi(void (*crash_ipi_callback)(struct pt_regs *))
157 crash_ipi_function_ptr = crash_ipi_callback;
158 if (crash_ipi_callback && smp_ops) {
160 smp_ops->message_pass(MSG_ALL_BUT_SELF, PPC_MSG_DEBUGGER_BREAK);
165 static void stop_this_cpu(void *dummy)
172 void smp_send_stop(void)
174 smp_call_function(stop_this_cpu, NULL, 0);
177 struct thread_info *current_set[NR_CPUS];
179 static void __devinit smp_store_cpu_info(int id)
181 per_cpu(pvr, id) = mfspr(SPRN_PVR);
184 static void __init smp_create_idle(unsigned int cpu)
186 struct task_struct *p;
188 /* create a process for the processor */
191 panic("failed fork for CPU %u: %li", cpu, PTR_ERR(p));
193 paca[cpu].__current = p;
194 paca[cpu].kstack = (unsigned long) task_thread_info(p)
195 + THREAD_SIZE - STACK_FRAME_OVERHEAD;
197 current_set[cpu] = task_thread_info(p);
198 task_thread_info(p)->cpu = cpu;
201 void __init smp_prepare_cpus(unsigned int max_cpus)
205 DBG("smp_prepare_cpus\n");
208 * setup_cpu may need to be called on the boot cpu. We havent
209 * spun any cpus up but lets be paranoid.
211 BUG_ON(boot_cpuid != smp_processor_id());
214 smp_store_cpu_info(boot_cpuid);
215 cpu_callin_map[boot_cpuid] = 1;
218 max_cpus = smp_ops->probe();
222 smp_space_timers(max_cpus);
224 for_each_possible_cpu(cpu)
225 if (cpu != boot_cpuid)
226 smp_create_idle(cpu);
229 void __devinit smp_prepare_boot_cpu(void)
231 BUG_ON(smp_processor_id() != boot_cpuid);
233 cpu_set(boot_cpuid, cpu_online_map);
234 cpu_set(boot_cpuid, per_cpu(cpu_sibling_map, boot_cpuid));
235 cpu_set(boot_cpuid, per_cpu(cpu_core_map, boot_cpuid));
237 paca[boot_cpuid].__current = current;
239 current_set[boot_cpuid] = task_thread_info(current);
242 #ifdef CONFIG_HOTPLUG_CPU
243 /* State of each CPU during hotplug phases */
244 DEFINE_PER_CPU(int, cpu_state) = { 0 };
246 int generic_cpu_disable(void)
248 unsigned int cpu = smp_processor_id();
250 if (cpu == boot_cpuid)
253 cpu_clear(cpu, cpu_online_map);
255 vdso_data->processorCount--;
256 fixup_irqs(cpu_online_map);
261 int generic_cpu_enable(unsigned int cpu)
263 /* Do the normal bootup if we haven't
264 * already bootstrapped. */
265 if (system_state != SYSTEM_RUNNING)
268 /* get the target out of it's holding state */
269 per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
272 while (!cpu_online(cpu))
276 fixup_irqs(cpu_online_map);
277 /* counter the irq disable in fixup_irqs */
283 void generic_cpu_die(unsigned int cpu)
287 for (i = 0; i < 100; i++) {
289 if (per_cpu(cpu_state, cpu) == CPU_DEAD)
293 printk(KERN_ERR "CPU%d didn't die...\n", cpu);
296 void generic_mach_cpu_die(void)
301 cpu = smp_processor_id();
302 printk(KERN_DEBUG "CPU%d offline\n", cpu);
303 __get_cpu_var(cpu_state) = CPU_DEAD;
305 while (__get_cpu_var(cpu_state) != CPU_UP_PREPARE)
307 cpu_set(cpu, cpu_online_map);
312 static int __devinit cpu_enable(unsigned int cpu)
314 if (smp_ops && smp_ops->cpu_enable)
315 return smp_ops->cpu_enable(cpu);
320 int __cpuinit __cpu_up(unsigned int cpu)
324 secondary_ti = current_set[cpu];
325 if (!cpu_enable(cpu))
328 if (smp_ops == NULL ||
329 (smp_ops->cpu_bootable && !smp_ops->cpu_bootable(cpu)))
332 /* Make sure callin-map entry is 0 (can be leftover a CPU
335 cpu_callin_map[cpu] = 0;
337 /* The information for processor bringup must
338 * be written out to main store before we release
344 DBG("smp: kicking cpu %d\n", cpu);
345 smp_ops->kick_cpu(cpu);
348 * wait to see if the cpu made a callin (is actually up).
349 * use this value that I found through experimentation.
352 if (system_state < SYSTEM_RUNNING)
353 for (c = 50000; c && !cpu_callin_map[cpu]; c--)
355 #ifdef CONFIG_HOTPLUG_CPU
358 * CPUs can take much longer to come up in the
359 * hotplug case. Wait five seconds.
361 for (c = 25; c && !cpu_callin_map[cpu]; c--) {
366 if (!cpu_callin_map[cpu]) {
367 printk("Processor %u is stuck.\n", cpu);
371 printk("Processor %u found.\n", cpu);
373 if (smp_ops->give_timebase)
374 smp_ops->give_timebase();
376 /* Wait until cpu puts itself in the online map */
377 while (!cpu_online(cpu))
383 /* Return the value of the reg property corresponding to the given
386 int cpu_to_core_id(int cpu)
388 struct device_node *np;
392 np = of_get_cpu_node(cpu, NULL);
396 reg = of_get_property(np, "reg", NULL);
406 /* Must be called when no change can occur to cpu_present_map,
407 * i.e. during cpu online or offline.
409 static struct device_node *cpu_to_l2cache(int cpu)
411 struct device_node *np;
415 if (!cpu_present(cpu))
418 np = of_get_cpu_node(cpu, NULL);
422 php = of_get_property(np, "l2-cache", NULL);
428 return of_find_node_by_phandle(ph);
431 /* Activate a secondary processor. */
432 int __devinit start_secondary(void *unused)
434 unsigned int cpu = smp_processor_id();
435 struct device_node *l2_cache;
438 atomic_inc(&init_mm.mm_count);
439 current->active_mm = &init_mm;
441 smp_store_cpu_info(cpu);
442 set_dec(tb_ticks_per_jiffy);
444 cpu_callin_map[cpu] = 1;
446 smp_ops->setup_cpu(cpu);
447 if (smp_ops->take_timebase)
448 smp_ops->take_timebase();
450 if (system_state > SYSTEM_BOOTING)
453 secondary_cpu_time_init();
456 notify_cpu_starting(cpu);
457 cpu_set(cpu, cpu_online_map);
458 /* Update sibling maps */
459 base = cpu_first_thread_in_core(cpu);
460 for (i = 0; i < threads_per_core; i++) {
461 if (cpu_is_offline(base + i))
463 cpu_set(cpu, per_cpu(cpu_sibling_map, base + i));
464 cpu_set(base + i, per_cpu(cpu_sibling_map, cpu));
466 /* cpu_core_map should be a superset of
467 * cpu_sibling_map even if we don't have cache
468 * information, so update the former here, too.
470 cpu_set(cpu, per_cpu(cpu_core_map, base +i));
471 cpu_set(base + i, per_cpu(cpu_core_map, cpu));
473 l2_cache = cpu_to_l2cache(cpu);
474 for_each_online_cpu(i) {
475 struct device_node *np = cpu_to_l2cache(i);
478 if (np == l2_cache) {
479 cpu_set(cpu, per_cpu(cpu_core_map, i));
480 cpu_set(i, per_cpu(cpu_core_map, cpu));
484 of_node_put(l2_cache);
493 int setup_profiling_timer(unsigned int multiplier)
498 void __init smp_cpus_done(unsigned int max_cpus)
502 /* We want the setup_cpu() here to be called from CPU 0, but our
503 * init thread may have been "borrowed" by another CPU in the meantime
504 * se we pin us down to CPU 0 for a short while
506 old_mask = current->cpus_allowed;
507 set_cpus_allowed(current, cpumask_of_cpu(boot_cpuid));
510 smp_ops->setup_cpu(boot_cpuid);
512 set_cpus_allowed(current, old_mask);
514 snapshot_timebases();
516 dump_numa_cpu_topology();
519 #ifdef CONFIG_HOTPLUG_CPU
520 int __cpu_disable(void)
522 struct device_node *l2_cache;
523 int cpu = smp_processor_id();
527 if (!smp_ops->cpu_disable)
530 err = smp_ops->cpu_disable();
534 /* Update sibling maps */
535 base = cpu_first_thread_in_core(cpu);
536 for (i = 0; i < threads_per_core; i++) {
537 cpu_clear(cpu, per_cpu(cpu_sibling_map, base + i));
538 cpu_clear(base + i, per_cpu(cpu_sibling_map, cpu));
539 cpu_clear(cpu, per_cpu(cpu_core_map, base +i));
540 cpu_clear(base + i, per_cpu(cpu_core_map, cpu));
543 l2_cache = cpu_to_l2cache(cpu);
544 for_each_present_cpu(i) {
545 struct device_node *np = cpu_to_l2cache(i);
548 if (np == l2_cache) {
549 cpu_clear(cpu, per_cpu(cpu_core_map, i));
550 cpu_clear(i, per_cpu(cpu_core_map, cpu));
554 of_node_put(l2_cache);
560 void __cpu_die(unsigned int cpu)
562 if (smp_ops->cpu_die)
563 smp_ops->cpu_die(cpu);