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 DEFINE_PER_CPU(cpumask_t, cpu_sibling_map) = CPU_MASK_NONE;
64 DEFINE_PER_CPU(cpumask_t, cpu_core_map) = CPU_MASK_NONE;
66 EXPORT_PER_CPU_SYMBOL(cpu_sibling_map);
67 EXPORT_PER_CPU_SYMBOL(cpu_core_map);
69 /* SMP operations for this machine */
70 struct smp_ops_t *smp_ops;
72 static volatile unsigned int cpu_callin_map[NR_CPUS];
74 int smt_enabled_at_boot = 1;
76 static void (*crash_ipi_function_ptr)(struct pt_regs *) = NULL;
79 void __devinit smp_generic_kick_cpu(int nr)
81 BUG_ON(nr < 0 || nr >= NR_CPUS);
84 * The processor is currently spinning, waiting for the
85 * cpu_start field to become non-zero After we set cpu_start,
86 * the processor will continue on to secondary_start
88 paca[nr].cpu_start = 1;
93 void smp_message_recv(int msg)
96 case PPC_MSG_CALL_FUNCTION:
97 generic_smp_call_function_interrupt();
99 case PPC_MSG_RESCHEDULE:
100 /* we notice need_resched on exit */
102 case PPC_MSG_CALL_FUNC_SINGLE:
103 generic_smp_call_function_single_interrupt();
105 case PPC_MSG_DEBUGGER_BREAK:
106 if (crash_ipi_function_ptr) {
107 crash_ipi_function_ptr(get_irq_regs());
110 #ifdef CONFIG_DEBUGGER
111 debugger_ipi(get_irq_regs());
113 #endif /* CONFIG_DEBUGGER */
116 printk("SMP %d: smp_message_recv(): unknown msg %d\n",
117 smp_processor_id(), msg);
122 void smp_send_reschedule(int cpu)
125 smp_ops->message_pass(cpu, PPC_MSG_RESCHEDULE);
128 void arch_send_call_function_single_ipi(int cpu)
130 smp_ops->message_pass(cpu, PPC_MSG_CALL_FUNC_SINGLE);
133 void arch_send_call_function_ipi(cpumask_t mask)
137 for_each_cpu_mask(cpu, mask)
138 smp_ops->message_pass(cpu, PPC_MSG_CALL_FUNCTION);
141 #ifdef CONFIG_DEBUGGER
142 void smp_send_debugger_break(int cpu)
145 smp_ops->message_pass(cpu, PPC_MSG_DEBUGGER_BREAK);
150 void crash_send_ipi(void (*crash_ipi_callback)(struct pt_regs *))
152 crash_ipi_function_ptr = crash_ipi_callback;
153 if (crash_ipi_callback && smp_ops) {
155 smp_ops->message_pass(MSG_ALL_BUT_SELF, PPC_MSG_DEBUGGER_BREAK);
160 static void stop_this_cpu(void *dummy)
167 void smp_send_stop(void)
169 smp_call_function(stop_this_cpu, NULL, 0);
172 struct thread_info *current_set[NR_CPUS];
174 static void __devinit smp_store_cpu_info(int id)
176 per_cpu(pvr, id) = mfspr(SPRN_PVR);
179 static void __init smp_create_idle(unsigned int cpu)
181 struct task_struct *p;
183 /* create a process for the processor */
186 panic("failed fork for CPU %u: %li", cpu, PTR_ERR(p));
188 paca[cpu].__current = p;
189 paca[cpu].kstack = (unsigned long) task_thread_info(p)
190 + THREAD_SIZE - STACK_FRAME_OVERHEAD;
192 current_set[cpu] = task_thread_info(p);
193 task_thread_info(p)->cpu = cpu;
196 void __init smp_prepare_cpus(unsigned int max_cpus)
200 DBG("smp_prepare_cpus\n");
203 * setup_cpu may need to be called on the boot cpu. We havent
204 * spun any cpus up but lets be paranoid.
206 BUG_ON(boot_cpuid != smp_processor_id());
209 smp_store_cpu_info(boot_cpuid);
210 cpu_callin_map[boot_cpuid] = 1;
213 max_cpus = smp_ops->probe();
217 smp_space_timers(max_cpus);
219 for_each_possible_cpu(cpu)
220 if (cpu != boot_cpuid)
221 smp_create_idle(cpu);
224 void __devinit smp_prepare_boot_cpu(void)
226 BUG_ON(smp_processor_id() != boot_cpuid);
228 cpu_set(boot_cpuid, cpu_online_map);
229 cpu_set(boot_cpuid, per_cpu(cpu_sibling_map, boot_cpuid));
230 cpu_set(boot_cpuid, per_cpu(cpu_core_map, boot_cpuid));
232 paca[boot_cpuid].__current = current;
234 current_set[boot_cpuid] = task_thread_info(current);
237 #ifdef CONFIG_HOTPLUG_CPU
238 /* State of each CPU during hotplug phases */
239 DEFINE_PER_CPU(int, cpu_state) = { 0 };
241 int generic_cpu_disable(void)
243 unsigned int cpu = smp_processor_id();
245 if (cpu == boot_cpuid)
248 cpu_clear(cpu, cpu_online_map);
250 vdso_data->processorCount--;
251 fixup_irqs(cpu_online_map);
256 int generic_cpu_enable(unsigned int cpu)
258 /* Do the normal bootup if we haven't
259 * already bootstrapped. */
260 if (system_state != SYSTEM_RUNNING)
263 /* get the target out of it's holding state */
264 per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
267 while (!cpu_online(cpu))
271 fixup_irqs(cpu_online_map);
272 /* counter the irq disable in fixup_irqs */
278 void generic_cpu_die(unsigned int cpu)
282 for (i = 0; i < 100; i++) {
284 if (per_cpu(cpu_state, cpu) == CPU_DEAD)
288 printk(KERN_ERR "CPU%d didn't die...\n", cpu);
291 void generic_mach_cpu_die(void)
296 cpu = smp_processor_id();
297 printk(KERN_DEBUG "CPU%d offline\n", cpu);
298 __get_cpu_var(cpu_state) = CPU_DEAD;
300 while (__get_cpu_var(cpu_state) != CPU_UP_PREPARE)
302 cpu_set(cpu, cpu_online_map);
307 static int __devinit cpu_enable(unsigned int cpu)
309 if (smp_ops && smp_ops->cpu_enable)
310 return smp_ops->cpu_enable(cpu);
315 int __cpuinit __cpu_up(unsigned int cpu)
319 secondary_ti = current_set[cpu];
320 if (!cpu_enable(cpu))
323 if (smp_ops == NULL ||
324 (smp_ops->cpu_bootable && !smp_ops->cpu_bootable(cpu)))
327 /* Make sure callin-map entry is 0 (can be leftover a CPU
330 cpu_callin_map[cpu] = 0;
332 /* The information for processor bringup must
333 * be written out to main store before we release
339 DBG("smp: kicking cpu %d\n", cpu);
340 smp_ops->kick_cpu(cpu);
343 * wait to see if the cpu made a callin (is actually up).
344 * use this value that I found through experimentation.
347 if (system_state < SYSTEM_RUNNING)
348 for (c = 50000; c && !cpu_callin_map[cpu]; c--)
350 #ifdef CONFIG_HOTPLUG_CPU
353 * CPUs can take much longer to come up in the
354 * hotplug case. Wait five seconds.
356 for (c = 25; c && !cpu_callin_map[cpu]; c--) {
361 if (!cpu_callin_map[cpu]) {
362 printk("Processor %u is stuck.\n", cpu);
366 printk("Processor %u found.\n", cpu);
368 if (smp_ops->give_timebase)
369 smp_ops->give_timebase();
371 /* Wait until cpu puts itself in the online map */
372 while (!cpu_online(cpu))
378 /* Return the value of the reg property corresponding to the given
381 int cpu_to_core_id(int cpu)
383 struct device_node *np;
387 np = of_get_cpu_node(cpu, NULL);
391 reg = of_get_property(np, "reg", NULL);
401 /* Must be called when no change can occur to cpu_present_map,
402 * i.e. during cpu online or offline.
404 static struct device_node *cpu_to_l2cache(int cpu)
406 struct device_node *np;
410 if (!cpu_present(cpu))
413 np = of_get_cpu_node(cpu, NULL);
417 php = of_get_property(np, "l2-cache", NULL);
423 return of_find_node_by_phandle(ph);
426 /* Activate a secondary processor. */
427 int __devinit start_secondary(void *unused)
429 unsigned int cpu = smp_processor_id();
430 struct device_node *l2_cache;
433 atomic_inc(&init_mm.mm_count);
434 current->active_mm = &init_mm;
436 smp_store_cpu_info(cpu);
437 set_dec(tb_ticks_per_jiffy);
439 cpu_callin_map[cpu] = 1;
441 smp_ops->setup_cpu(cpu);
442 if (smp_ops->take_timebase)
443 smp_ops->take_timebase();
445 if (system_state > SYSTEM_BOOTING)
448 secondary_cpu_time_init();
451 notify_cpu_starting(cpu);
452 cpu_set(cpu, cpu_online_map);
453 /* Update sibling maps */
454 base = cpu_first_thread_in_core(cpu);
455 for (i = 0; i < threads_per_core; i++) {
456 if (cpu_is_offline(base + i))
458 cpu_set(cpu, per_cpu(cpu_sibling_map, base + i));
459 cpu_set(base + i, per_cpu(cpu_sibling_map, cpu));
461 /* cpu_core_map should be a superset of
462 * cpu_sibling_map even if we don't have cache
463 * information, so update the former here, too.
465 cpu_set(cpu, per_cpu(cpu_core_map, base +i));
466 cpu_set(base + i, per_cpu(cpu_core_map, cpu));
468 l2_cache = cpu_to_l2cache(cpu);
469 for_each_online_cpu(i) {
470 struct device_node *np = cpu_to_l2cache(i);
473 if (np == l2_cache) {
474 cpu_set(cpu, per_cpu(cpu_core_map, i));
475 cpu_set(i, per_cpu(cpu_core_map, cpu));
479 of_node_put(l2_cache);
488 int setup_profiling_timer(unsigned int multiplier)
493 void __init smp_cpus_done(unsigned int max_cpus)
497 /* We want the setup_cpu() here to be called from CPU 0, but our
498 * init thread may have been "borrowed" by another CPU in the meantime
499 * se we pin us down to CPU 0 for a short while
501 old_mask = current->cpus_allowed;
502 set_cpus_allowed(current, cpumask_of_cpu(boot_cpuid));
505 smp_ops->setup_cpu(boot_cpuid);
507 set_cpus_allowed(current, old_mask);
509 snapshot_timebases();
511 dump_numa_cpu_topology();
514 #ifdef CONFIG_HOTPLUG_CPU
515 int __cpu_disable(void)
517 struct device_node *l2_cache;
518 int cpu = smp_processor_id();
522 if (!smp_ops->cpu_disable)
525 err = smp_ops->cpu_disable();
529 /* Update sibling maps */
530 base = cpu_first_thread_in_core(cpu);
531 for (i = 0; i < threads_per_core; i++) {
532 cpu_clear(cpu, per_cpu(cpu_sibling_map, base + i));
533 cpu_clear(base + i, per_cpu(cpu_sibling_map, cpu));
534 cpu_clear(cpu, per_cpu(cpu_core_map, base +i));
535 cpu_clear(base + i, per_cpu(cpu_core_map, cpu));
538 l2_cache = cpu_to_l2cache(cpu);
539 for_each_present_cpu(i) {
540 struct device_node *np = cpu_to_l2cache(i);
543 if (np == l2_cache) {
544 cpu_clear(cpu, per_cpu(cpu_core_map, i));
545 cpu_clear(i, per_cpu(cpu_core_map, cpu));
549 of_node_put(l2_cache);
555 void __cpu_die(unsigned int cpu)
557 if (smp_ops->cpu_die)
558 smp_ops->cpu_die(cpu);