x86/efi: Enforce CONFIG_RELOCATABLE for EFI boot stub
[linux/fpc-iii.git] / arch / powerpc / kernel / smp.c
blob8e59abc237d7f17c96effa20583206e75b2e4b7a
1 /*
2 * SMP support for ppc.
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.
18 #undef DEBUG
20 #include <linux/kernel.h>
21 #include <linux/export.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/device.h>
31 #include <linux/cpu.h>
32 #include <linux/notifier.h>
33 #include <linux/topology.h>
35 #include <asm/ptrace.h>
36 #include <linux/atomic.h>
37 #include <asm/irq.h>
38 #include <asm/page.h>
39 #include <asm/pgtable.h>
40 #include <asm/prom.h>
41 #include <asm/smp.h>
42 #include <asm/time.h>
43 #include <asm/machdep.h>
44 #include <asm/cputhreads.h>
45 #include <asm/cputable.h>
46 #include <asm/mpic.h>
47 #include <asm/vdso_datapage.h>
48 #ifdef CONFIG_PPC64
49 #include <asm/paca.h>
50 #endif
51 #include <asm/vdso.h>
52 #include <asm/debug.h>
54 #ifdef DEBUG
55 #include <asm/udbg.h>
56 #define DBG(fmt...) udbg_printf(fmt)
57 #else
58 #define DBG(fmt...)
59 #endif
61 #ifdef CONFIG_HOTPLUG_CPU
62 /* State of each CPU during hotplug phases */
63 static DEFINE_PER_CPU(int, cpu_state) = { 0 };
64 #endif
66 struct thread_info *secondary_ti;
68 DEFINE_PER_CPU(cpumask_var_t, cpu_sibling_map);
69 DEFINE_PER_CPU(cpumask_var_t, cpu_core_map);
71 EXPORT_PER_CPU_SYMBOL(cpu_sibling_map);
72 EXPORT_PER_CPU_SYMBOL(cpu_core_map);
74 /* SMP operations for this machine */
75 struct smp_ops_t *smp_ops;
77 /* Can't be static due to PowerMac hackery */
78 volatile unsigned int cpu_callin_map[NR_CPUS];
80 int smt_enabled_at_boot = 1;
82 static void (*crash_ipi_function_ptr)(struct pt_regs *) = NULL;
85 * Returns 1 if the specified cpu should be brought up during boot.
86 * Used to inhibit booting threads if they've been disabled or
87 * limited on the command line
89 int smp_generic_cpu_bootable(unsigned int nr)
91 /* Special case - we inhibit secondary thread startup
92 * during boot if the user requests it.
94 if (system_state == SYSTEM_BOOTING && cpu_has_feature(CPU_FTR_SMT)) {
95 if (!smt_enabled_at_boot && cpu_thread_in_core(nr) != 0)
96 return 0;
97 if (smt_enabled_at_boot
98 && cpu_thread_in_core(nr) >= smt_enabled_at_boot)
99 return 0;
102 return 1;
106 #ifdef CONFIG_PPC64
107 int smp_generic_kick_cpu(int nr)
109 BUG_ON(nr < 0 || nr >= NR_CPUS);
112 * The processor is currently spinning, waiting for the
113 * cpu_start field to become non-zero After we set cpu_start,
114 * the processor will continue on to secondary_start
116 if (!paca[nr].cpu_start) {
117 paca[nr].cpu_start = 1;
118 smp_mb();
119 return 0;
122 #ifdef CONFIG_HOTPLUG_CPU
124 * Ok it's not there, so it might be soft-unplugged, let's
125 * try to bring it back
127 generic_set_cpu_up(nr);
128 smp_wmb();
129 smp_send_reschedule(nr);
130 #endif /* CONFIG_HOTPLUG_CPU */
132 return 0;
134 #endif /* CONFIG_PPC64 */
136 static irqreturn_t call_function_action(int irq, void *data)
138 generic_smp_call_function_interrupt();
139 return IRQ_HANDLED;
142 static irqreturn_t reschedule_action(int irq, void *data)
144 scheduler_ipi();
145 return IRQ_HANDLED;
148 static irqreturn_t call_function_single_action(int irq, void *data)
150 generic_smp_call_function_single_interrupt();
151 return IRQ_HANDLED;
154 static irqreturn_t debug_ipi_action(int irq, void *data)
156 if (crash_ipi_function_ptr) {
157 crash_ipi_function_ptr(get_irq_regs());
158 return IRQ_HANDLED;
161 #ifdef CONFIG_DEBUGGER
162 debugger_ipi(get_irq_regs());
163 #endif /* CONFIG_DEBUGGER */
165 return IRQ_HANDLED;
168 static irq_handler_t smp_ipi_action[] = {
169 [PPC_MSG_CALL_FUNCTION] = call_function_action,
170 [PPC_MSG_RESCHEDULE] = reschedule_action,
171 [PPC_MSG_CALL_FUNC_SINGLE] = call_function_single_action,
172 [PPC_MSG_DEBUGGER_BREAK] = debug_ipi_action,
175 const char *smp_ipi_name[] = {
176 [PPC_MSG_CALL_FUNCTION] = "ipi call function",
177 [PPC_MSG_RESCHEDULE] = "ipi reschedule",
178 [PPC_MSG_CALL_FUNC_SINGLE] = "ipi call function single",
179 [PPC_MSG_DEBUGGER_BREAK] = "ipi debugger",
182 /* optional function to request ipi, for controllers with >= 4 ipis */
183 int smp_request_message_ipi(int virq, int msg)
185 int err;
187 if (msg < 0 || msg > PPC_MSG_DEBUGGER_BREAK) {
188 return -EINVAL;
190 #if !defined(CONFIG_DEBUGGER) && !defined(CONFIG_KEXEC)
191 if (msg == PPC_MSG_DEBUGGER_BREAK) {
192 return 1;
194 #endif
195 err = request_irq(virq, smp_ipi_action[msg],
196 IRQF_PERCPU | IRQF_NO_THREAD | IRQF_NO_SUSPEND,
197 smp_ipi_name[msg], NULL);
198 WARN(err < 0, "unable to request_irq %d for %s (rc %d)\n",
199 virq, smp_ipi_name[msg], err);
201 return err;
204 #ifdef CONFIG_PPC_SMP_MUXED_IPI
205 struct cpu_messages {
206 int messages; /* current messages */
207 unsigned long data; /* data for cause ipi */
209 static DEFINE_PER_CPU_SHARED_ALIGNED(struct cpu_messages, ipi_message);
211 void smp_muxed_ipi_set_data(int cpu, unsigned long data)
213 struct cpu_messages *info = &per_cpu(ipi_message, cpu);
215 info->data = data;
218 void smp_muxed_ipi_message_pass(int cpu, int msg)
220 struct cpu_messages *info = &per_cpu(ipi_message, cpu);
221 char *message = (char *)&info->messages;
224 * Order previous accesses before accesses in the IPI handler.
226 smp_mb();
227 message[msg] = 1;
229 * cause_ipi functions are required to include a full barrier
230 * before doing whatever causes the IPI.
232 smp_ops->cause_ipi(cpu, info->data);
235 #ifdef __BIG_ENDIAN__
236 #define IPI_MESSAGE(A) (1 << (24 - 8 * (A)))
237 #else
238 #define IPI_MESSAGE(A) (1 << (8 * (A)))
239 #endif
241 irqreturn_t smp_ipi_demux(void)
243 struct cpu_messages *info = &__get_cpu_var(ipi_message);
244 unsigned int all;
246 mb(); /* order any irq clear */
248 do {
249 all = xchg(&info->messages, 0);
250 if (all & IPI_MESSAGE(PPC_MSG_CALL_FUNCTION))
251 generic_smp_call_function_interrupt();
252 if (all & IPI_MESSAGE(PPC_MSG_RESCHEDULE))
253 scheduler_ipi();
254 if (all & IPI_MESSAGE(PPC_MSG_CALL_FUNC_SINGLE))
255 generic_smp_call_function_single_interrupt();
256 if (all & IPI_MESSAGE(PPC_MSG_DEBUGGER_BREAK))
257 debug_ipi_action(0, NULL);
258 } while (info->messages);
260 return IRQ_HANDLED;
262 #endif /* CONFIG_PPC_SMP_MUXED_IPI */
264 static inline void do_message_pass(int cpu, int msg)
266 if (smp_ops->message_pass)
267 smp_ops->message_pass(cpu, msg);
268 #ifdef CONFIG_PPC_SMP_MUXED_IPI
269 else
270 smp_muxed_ipi_message_pass(cpu, msg);
271 #endif
274 void smp_send_reschedule(int cpu)
276 if (likely(smp_ops))
277 do_message_pass(cpu, PPC_MSG_RESCHEDULE);
279 EXPORT_SYMBOL_GPL(smp_send_reschedule);
281 void arch_send_call_function_single_ipi(int cpu)
283 do_message_pass(cpu, PPC_MSG_CALL_FUNC_SINGLE);
286 void arch_send_call_function_ipi_mask(const struct cpumask *mask)
288 unsigned int cpu;
290 for_each_cpu(cpu, mask)
291 do_message_pass(cpu, PPC_MSG_CALL_FUNCTION);
294 #if defined(CONFIG_DEBUGGER) || defined(CONFIG_KEXEC)
295 void smp_send_debugger_break(void)
297 int cpu;
298 int me = raw_smp_processor_id();
300 if (unlikely(!smp_ops))
301 return;
303 for_each_online_cpu(cpu)
304 if (cpu != me)
305 do_message_pass(cpu, PPC_MSG_DEBUGGER_BREAK);
307 #endif
309 #ifdef CONFIG_KEXEC
310 void crash_send_ipi(void (*crash_ipi_callback)(struct pt_regs *))
312 crash_ipi_function_ptr = crash_ipi_callback;
313 if (crash_ipi_callback) {
314 mb();
315 smp_send_debugger_break();
318 #endif
320 static void stop_this_cpu(void *dummy)
322 /* Remove this CPU */
323 set_cpu_online(smp_processor_id(), false);
325 local_irq_disable();
326 while (1)
330 void smp_send_stop(void)
332 smp_call_function(stop_this_cpu, NULL, 0);
335 struct thread_info *current_set[NR_CPUS];
337 static void smp_store_cpu_info(int id)
339 per_cpu(cpu_pvr, id) = mfspr(SPRN_PVR);
340 #ifdef CONFIG_PPC_FSL_BOOK3E
341 per_cpu(next_tlbcam_idx, id)
342 = (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1;
343 #endif
346 void __init smp_prepare_cpus(unsigned int max_cpus)
348 unsigned int cpu;
350 DBG("smp_prepare_cpus\n");
353 * setup_cpu may need to be called on the boot cpu. We havent
354 * spun any cpus up but lets be paranoid.
356 BUG_ON(boot_cpuid != smp_processor_id());
358 /* Fixup boot cpu */
359 smp_store_cpu_info(boot_cpuid);
360 cpu_callin_map[boot_cpuid] = 1;
362 for_each_possible_cpu(cpu) {
363 zalloc_cpumask_var_node(&per_cpu(cpu_sibling_map, cpu),
364 GFP_KERNEL, cpu_to_node(cpu));
365 zalloc_cpumask_var_node(&per_cpu(cpu_core_map, cpu),
366 GFP_KERNEL, cpu_to_node(cpu));
369 cpumask_set_cpu(boot_cpuid, cpu_sibling_mask(boot_cpuid));
370 cpumask_set_cpu(boot_cpuid, cpu_core_mask(boot_cpuid));
372 if (smp_ops)
373 if (smp_ops->probe)
374 max_cpus = smp_ops->probe();
375 else
376 max_cpus = NR_CPUS;
377 else
378 max_cpus = 1;
381 void smp_prepare_boot_cpu(void)
383 BUG_ON(smp_processor_id() != boot_cpuid);
384 #ifdef CONFIG_PPC64
385 paca[boot_cpuid].__current = current;
386 #endif
387 current_set[boot_cpuid] = task_thread_info(current);
390 #ifdef CONFIG_HOTPLUG_CPU
392 int generic_cpu_disable(void)
394 unsigned int cpu = smp_processor_id();
396 if (cpu == boot_cpuid)
397 return -EBUSY;
399 set_cpu_online(cpu, false);
400 #ifdef CONFIG_PPC64
401 vdso_data->processorCount--;
402 #endif
403 migrate_irqs();
404 return 0;
407 void generic_cpu_die(unsigned int cpu)
409 int i;
411 for (i = 0; i < 100; i++) {
412 smp_rmb();
413 if (per_cpu(cpu_state, cpu) == CPU_DEAD)
414 return;
415 msleep(100);
417 printk(KERN_ERR "CPU%d didn't die...\n", cpu);
420 void generic_mach_cpu_die(void)
422 unsigned int cpu;
424 local_irq_disable();
425 idle_task_exit();
426 cpu = smp_processor_id();
427 printk(KERN_DEBUG "CPU%d offline\n", cpu);
428 __get_cpu_var(cpu_state) = CPU_DEAD;
429 smp_wmb();
430 while (__get_cpu_var(cpu_state) != CPU_UP_PREPARE)
431 cpu_relax();
434 void generic_set_cpu_dead(unsigned int cpu)
436 per_cpu(cpu_state, cpu) = CPU_DEAD;
440 * The cpu_state should be set to CPU_UP_PREPARE in kick_cpu(), otherwise
441 * the cpu_state is always CPU_DEAD after calling generic_set_cpu_dead(),
442 * which makes the delay in generic_cpu_die() not happen.
444 void generic_set_cpu_up(unsigned int cpu)
446 per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
449 int generic_check_cpu_restart(unsigned int cpu)
451 return per_cpu(cpu_state, cpu) == CPU_UP_PREPARE;
454 static atomic_t secondary_inhibit_count;
457 * Don't allow secondary CPU threads to come online
459 void inhibit_secondary_onlining(void)
462 * This makes secondary_inhibit_count stable during cpu
463 * online/offline operations.
465 get_online_cpus();
467 atomic_inc(&secondary_inhibit_count);
468 put_online_cpus();
470 EXPORT_SYMBOL_GPL(inhibit_secondary_onlining);
473 * Allow secondary CPU threads to come online again
475 void uninhibit_secondary_onlining(void)
477 get_online_cpus();
478 atomic_dec(&secondary_inhibit_count);
479 put_online_cpus();
481 EXPORT_SYMBOL_GPL(uninhibit_secondary_onlining);
483 static int secondaries_inhibited(void)
485 return atomic_read(&secondary_inhibit_count);
488 #else /* HOTPLUG_CPU */
490 #define secondaries_inhibited() 0
492 #endif
494 static void cpu_idle_thread_init(unsigned int cpu, struct task_struct *idle)
496 struct thread_info *ti = task_thread_info(idle);
498 #ifdef CONFIG_PPC64
499 paca[cpu].__current = idle;
500 paca[cpu].kstack = (unsigned long)ti + THREAD_SIZE - STACK_FRAME_OVERHEAD;
501 #endif
502 ti->cpu = cpu;
503 secondary_ti = current_set[cpu] = ti;
506 int __cpu_up(unsigned int cpu, struct task_struct *tidle)
508 int rc, c;
511 * Don't allow secondary threads to come online if inhibited
513 if (threads_per_core > 1 && secondaries_inhibited() &&
514 cpu % threads_per_core != 0)
515 return -EBUSY;
517 if (smp_ops == NULL ||
518 (smp_ops->cpu_bootable && !smp_ops->cpu_bootable(cpu)))
519 return -EINVAL;
521 cpu_idle_thread_init(cpu, tidle);
523 /* Make sure callin-map entry is 0 (can be leftover a CPU
524 * hotplug
526 cpu_callin_map[cpu] = 0;
528 /* The information for processor bringup must
529 * be written out to main store before we release
530 * the processor.
532 smp_mb();
534 /* wake up cpus */
535 DBG("smp: kicking cpu %d\n", cpu);
536 rc = smp_ops->kick_cpu(cpu);
537 if (rc) {
538 pr_err("smp: failed starting cpu %d (rc %d)\n", cpu, rc);
539 return rc;
543 * wait to see if the cpu made a callin (is actually up).
544 * use this value that I found through experimentation.
545 * -- Cort
547 if (system_state < SYSTEM_RUNNING)
548 for (c = 50000; c && !cpu_callin_map[cpu]; c--)
549 udelay(100);
550 #ifdef CONFIG_HOTPLUG_CPU
551 else
553 * CPUs can take much longer to come up in the
554 * hotplug case. Wait five seconds.
556 for (c = 5000; c && !cpu_callin_map[cpu]; c--)
557 msleep(1);
558 #endif
560 if (!cpu_callin_map[cpu]) {
561 printk(KERN_ERR "Processor %u is stuck.\n", cpu);
562 return -ENOENT;
565 DBG("Processor %u found.\n", cpu);
567 if (smp_ops->give_timebase)
568 smp_ops->give_timebase();
570 /* Wait until cpu puts itself in the online map */
571 while (!cpu_online(cpu))
572 cpu_relax();
574 return 0;
577 /* Return the value of the reg property corresponding to the given
578 * logical cpu.
580 int cpu_to_core_id(int cpu)
582 struct device_node *np;
583 const int *reg;
584 int id = -1;
586 np = of_get_cpu_node(cpu, NULL);
587 if (!np)
588 goto out;
590 reg = of_get_property(np, "reg", NULL);
591 if (!reg)
592 goto out;
594 id = *reg;
595 out:
596 of_node_put(np);
597 return id;
600 /* Return the value of the chip-id property corresponding
601 * to the given logical cpu.
603 int cpu_to_chip_id(int cpu)
605 struct device_node *np;
607 np = of_get_cpu_node(cpu, NULL);
608 if (!np)
609 return -1;
611 of_node_put(np);
612 return of_get_ibm_chip_id(np);
614 EXPORT_SYMBOL(cpu_to_chip_id);
616 /* Helper routines for cpu to core mapping */
617 int cpu_core_index_of_thread(int cpu)
619 return cpu >> threads_shift;
621 EXPORT_SYMBOL_GPL(cpu_core_index_of_thread);
623 int cpu_first_thread_of_core(int core)
625 return core << threads_shift;
627 EXPORT_SYMBOL_GPL(cpu_first_thread_of_core);
629 static void traverse_siblings_chip_id(int cpu, bool add, int chipid)
631 const struct cpumask *mask;
632 struct device_node *np;
633 int i, plen;
634 const __be32 *prop;
636 mask = add ? cpu_online_mask : cpu_present_mask;
637 for_each_cpu(i, mask) {
638 np = of_get_cpu_node(i, NULL);
639 if (!np)
640 continue;
641 prop = of_get_property(np, "ibm,chip-id", &plen);
642 if (prop && plen == sizeof(int) &&
643 of_read_number(prop, 1) == chipid) {
644 if (add) {
645 cpumask_set_cpu(cpu, cpu_core_mask(i));
646 cpumask_set_cpu(i, cpu_core_mask(cpu));
647 } else {
648 cpumask_clear_cpu(cpu, cpu_core_mask(i));
649 cpumask_clear_cpu(i, cpu_core_mask(cpu));
652 of_node_put(np);
656 /* Must be called when no change can occur to cpu_present_mask,
657 * i.e. during cpu online or offline.
659 static struct device_node *cpu_to_l2cache(int cpu)
661 struct device_node *np;
662 struct device_node *cache;
664 if (!cpu_present(cpu))
665 return NULL;
667 np = of_get_cpu_node(cpu, NULL);
668 if (np == NULL)
669 return NULL;
671 cache = of_find_next_cache_node(np);
673 of_node_put(np);
675 return cache;
678 static void traverse_core_siblings(int cpu, bool add)
680 struct device_node *l2_cache, *np;
681 const struct cpumask *mask;
682 int i, chip, plen;
683 const __be32 *prop;
685 /* First see if we have ibm,chip-id properties in cpu nodes */
686 np = of_get_cpu_node(cpu, NULL);
687 if (np) {
688 chip = -1;
689 prop = of_get_property(np, "ibm,chip-id", &plen);
690 if (prop && plen == sizeof(int))
691 chip = of_read_number(prop, 1);
692 of_node_put(np);
693 if (chip >= 0) {
694 traverse_siblings_chip_id(cpu, add, chip);
695 return;
699 l2_cache = cpu_to_l2cache(cpu);
700 mask = add ? cpu_online_mask : cpu_present_mask;
701 for_each_cpu(i, mask) {
702 np = cpu_to_l2cache(i);
703 if (!np)
704 continue;
705 if (np == l2_cache) {
706 if (add) {
707 cpumask_set_cpu(cpu, cpu_core_mask(i));
708 cpumask_set_cpu(i, cpu_core_mask(cpu));
709 } else {
710 cpumask_clear_cpu(cpu, cpu_core_mask(i));
711 cpumask_clear_cpu(i, cpu_core_mask(cpu));
714 of_node_put(np);
716 of_node_put(l2_cache);
719 /* Activate a secondary processor. */
720 void start_secondary(void *unused)
722 unsigned int cpu = smp_processor_id();
723 int i, base;
725 atomic_inc(&init_mm.mm_count);
726 current->active_mm = &init_mm;
728 smp_store_cpu_info(cpu);
729 set_dec(tb_ticks_per_jiffy);
730 preempt_disable();
731 cpu_callin_map[cpu] = 1;
733 if (smp_ops->setup_cpu)
734 smp_ops->setup_cpu(cpu);
735 if (smp_ops->take_timebase)
736 smp_ops->take_timebase();
738 secondary_cpu_time_init();
740 #ifdef CONFIG_PPC64
741 if (system_state == SYSTEM_RUNNING)
742 vdso_data->processorCount++;
744 vdso_getcpu_init();
745 #endif
746 /* Update sibling maps */
747 base = cpu_first_thread_sibling(cpu);
748 for (i = 0; i < threads_per_core; i++) {
749 if (cpu_is_offline(base + i) && (cpu != base + i))
750 continue;
751 cpumask_set_cpu(cpu, cpu_sibling_mask(base + i));
752 cpumask_set_cpu(base + i, cpu_sibling_mask(cpu));
754 /* cpu_core_map should be a superset of
755 * cpu_sibling_map even if we don't have cache
756 * information, so update the former here, too.
758 cpumask_set_cpu(cpu, cpu_core_mask(base + i));
759 cpumask_set_cpu(base + i, cpu_core_mask(cpu));
761 traverse_core_siblings(cpu, true);
763 smp_wmb();
764 notify_cpu_starting(cpu);
765 set_cpu_online(cpu, true);
767 local_irq_enable();
769 cpu_startup_entry(CPUHP_ONLINE);
771 BUG();
774 int setup_profiling_timer(unsigned int multiplier)
776 return 0;
779 void __init smp_cpus_done(unsigned int max_cpus)
781 cpumask_var_t old_mask;
783 /* We want the setup_cpu() here to be called from CPU 0, but our
784 * init thread may have been "borrowed" by another CPU in the meantime
785 * se we pin us down to CPU 0 for a short while
787 alloc_cpumask_var(&old_mask, GFP_NOWAIT);
788 cpumask_copy(old_mask, tsk_cpus_allowed(current));
789 set_cpus_allowed_ptr(current, cpumask_of(boot_cpuid));
791 if (smp_ops && smp_ops->setup_cpu)
792 smp_ops->setup_cpu(boot_cpuid);
794 set_cpus_allowed_ptr(current, old_mask);
796 free_cpumask_var(old_mask);
798 if (smp_ops && smp_ops->bringup_done)
799 smp_ops->bringup_done();
801 dump_numa_cpu_topology();
805 int arch_sd_sibling_asym_packing(void)
807 if (cpu_has_feature(CPU_FTR_ASYM_SMT)) {
808 printk_once(KERN_INFO "Enabling Asymmetric SMT scheduling\n");
809 return SD_ASYM_PACKING;
811 return 0;
814 #ifdef CONFIG_HOTPLUG_CPU
815 int __cpu_disable(void)
817 int cpu = smp_processor_id();
818 int base, i;
819 int err;
821 if (!smp_ops->cpu_disable)
822 return -ENOSYS;
824 err = smp_ops->cpu_disable();
825 if (err)
826 return err;
828 /* Update sibling maps */
829 base = cpu_first_thread_sibling(cpu);
830 for (i = 0; i < threads_per_core; i++) {
831 cpumask_clear_cpu(cpu, cpu_sibling_mask(base + i));
832 cpumask_clear_cpu(base + i, cpu_sibling_mask(cpu));
833 cpumask_clear_cpu(cpu, cpu_core_mask(base + i));
834 cpumask_clear_cpu(base + i, cpu_core_mask(cpu));
836 traverse_core_siblings(cpu, false);
838 return 0;
841 void __cpu_die(unsigned int cpu)
843 if (smp_ops->cpu_die)
844 smp_ops->cpu_die(cpu);
847 static DEFINE_MUTEX(powerpc_cpu_hotplug_driver_mutex);
849 void cpu_hotplug_driver_lock()
851 mutex_lock(&powerpc_cpu_hotplug_driver_mutex);
854 void cpu_hotplug_driver_unlock()
856 mutex_unlock(&powerpc_cpu_hotplug_driver_mutex);
859 void cpu_die(void)
861 if (ppc_md.cpu_die)
862 ppc_md.cpu_die();
864 /* If we return, we re-enter start_secondary */
865 start_secondary_resume();
868 #endif