1 /*
2 * This program is free software; you can redistribute it and/or
3 * modify it under the terms of the GNU General Public License
4 * as published by the Free Software Foundation; either version 2
5 * of the License, or (at your option) any later version.
6 *
7 * This program is distributed in the hope that it will be useful,
8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10 * GNU General Public License for more details.
11 *
12 * You should have received a copy of the GNU General Public License
13 * along with this program; if not, write to the Free Software
14 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
15 *
16 * Copyright (C) 2000, 2001 Kanoj Sarcar
17 * Copyright (C) 2000, 2001 Ralf Baechle
18 * Copyright (C) 2000, 2001 Silicon Graphics, Inc.
19 * Copyright (C) 2000, 2001, 2003 Broadcom Corporation
20 */
21 #include <linux/cache.h>
22 #include <linux/delay.h>
23 #include <linux/init.h>
24 #include <linux/interrupt.h>
25 #include <linux/smp.h>
26 #include <linux/spinlock.h>
27 #include <linux/threads.h>
28 #include <linux/export.h>
29 #include <linux/time.h>
30 #include <linux/timex.h>
31 #include <linux/sched.h>
32 #include <linux/cpumask.h>
33 #include <linux/cpu.h>
34 #include <linux/err.h>
35 #include <linux/ftrace.h>
36 #include <linux/irqdomain.h>
37 #include <linux/of.h>
38 #include <linux/of_irq.h>
39
40 #include <linux/atomic.h>
41 #include <asm/cpu.h>
42 #include <asm/processor.h>
43 #include <asm/idle.h>
44 #include <asm/r4k-timer.h>
45 #include <asm/mips-cpc.h>
46 #include <asm/mmu_context.h>
47 #include <asm/time.h>
48 #include <asm/setup.h>
49 #include <asm/maar.h>
50
51 cpumask_t cpu_callin_map; /* Bitmask of started secondaries */
52
53 int __cpu_number_map[NR_CPUS]; /* Map physical to logical */
54 EXPORT_SYMBOL(__cpu_number_map);
55
56 int __cpu_logical_map[NR_CPUS]; /* Map logical to physical */
57 EXPORT_SYMBOL(__cpu_logical_map);
58
59 /* Number of TCs (or siblings in Intel speak) per CPU core */
60 int smp_num_siblings = 1;
61 EXPORT_SYMBOL(smp_num_siblings);
62
63 /* representing the TCs (or siblings in Intel speak) of each logical CPU */
64 cpumask_t cpu_sibling_map[NR_CPUS] __read_mostly;
65 EXPORT_SYMBOL(cpu_sibling_map);
66
67 /* representing the core map of multi-core chips of each logical CPU */
68 cpumask_t cpu_core_map[NR_CPUS] __read_mostly;
69 EXPORT_SYMBOL(cpu_core_map);
70
71 static DECLARE_COMPLETION(cpu_starting);
72 static DECLARE_COMPLETION(cpu_running);
73
74 /*
75 * A logcal cpu mask containing only one VPE per core to
76 * reduce the number of IPIs on large MT systems.
77 */
78 cpumask_t cpu_foreign_map[NR_CPUS] __read_mostly;
79 EXPORT_SYMBOL(cpu_foreign_map);
80
81 /* representing cpus for which sibling maps can be computed */
82 static cpumask_t cpu_sibling_setup_map;
83
84 /* representing cpus for which core maps can be computed */
85 static cpumask_t cpu_core_setup_map;
86
87 cpumask_t cpu_coherent_mask;
88
89 #ifdef CONFIG_GENERIC_IRQ_IPI
90 static struct irq_desc *call_desc;
91 static struct irq_desc *sched_desc;
92 #endif
93
set_cpu_sibling_map(int cpu)94 static inline void set_cpu_sibling_map(int cpu)
95 {
96 int i;
97
98 cpumask_set_cpu(cpu, &cpu_sibling_setup_map);
99
100 if (smp_num_siblings > 1) {
101 for_each_cpu(i, &cpu_sibling_setup_map) {
102 if (cpu_data[cpu].package == cpu_data[i].package &&
103 cpu_data[cpu].core == cpu_data[i].core) {
104 cpumask_set_cpu(i, &cpu_sibling_map[cpu]);
105 cpumask_set_cpu(cpu, &cpu_sibling_map[i]);
106 }
107 }
108 } else
109 cpumask_set_cpu(cpu, &cpu_sibling_map[cpu]);
110 }
111
set_cpu_core_map(int cpu)112 static inline void set_cpu_core_map(int cpu)
113 {
114 int i;
115
116 cpumask_set_cpu(cpu, &cpu_core_setup_map);
117
118 for_each_cpu(i, &cpu_core_setup_map) {
119 if (cpu_data[cpu].package == cpu_data[i].package) {
120 cpumask_set_cpu(i, &cpu_core_map[cpu]);
121 cpumask_set_cpu(cpu, &cpu_core_map[i]);
122 }
123 }
124 }
125
126 /*
127 * Calculate a new cpu_foreign_map mask whenever a
128 * new cpu appears or disappears.
129 */
calculate_cpu_foreign_map(void)130 void calculate_cpu_foreign_map(void)
131 {
132 int i, k, core_present;
133 cpumask_t temp_foreign_map;
134
135 /* Re-calculate the mask */
136 cpumask_clear(&temp_foreign_map);
137 for_each_online_cpu(i) {
138 core_present = 0;
139 for_each_cpu(k, &temp_foreign_map)
140 if (cpu_data[i].package == cpu_data[k].package &&
141 cpu_data[i].core == cpu_data[k].core)
142 core_present = 1;
143 if (!core_present)
144 cpumask_set_cpu(i, &temp_foreign_map);
145 }
146
147 for_each_online_cpu(i)
148 cpumask_andnot(&cpu_foreign_map[i],
149 &temp_foreign_map, &cpu_sibling_map[i]);
150 }
151
152 struct plat_smp_ops *mp_ops;
153 EXPORT_SYMBOL(mp_ops);
154
register_smp_ops(struct plat_smp_ops * ops)155 void register_smp_ops(struct plat_smp_ops *ops)
156 {
157 if (mp_ops)
158 printk(KERN_WARNING "Overriding previously set SMP ops\n");
159
160 mp_ops = ops;
161 }
162
163 #ifdef CONFIG_GENERIC_IRQ_IPI
mips_smp_send_ipi_single(int cpu,unsigned int action)164 void mips_smp_send_ipi_single(int cpu, unsigned int action)
165 {
166 mips_smp_send_ipi_mask(cpumask_of(cpu), action);
167 }
168
mips_smp_send_ipi_mask(const struct cpumask * mask,unsigned int action)169 void mips_smp_send_ipi_mask(const struct cpumask *mask, unsigned int action)
170 {
171 unsigned long flags;
172 unsigned int core;
173 int cpu;
174
175 local_irq_save(flags);
176
177 switch (action) {
178 case SMP_CALL_FUNCTION:
179 __ipi_send_mask(call_desc, mask);
180 break;
181
182 case SMP_RESCHEDULE_YOURSELF:
183 __ipi_send_mask(sched_desc, mask);
184 break;
185
186 default:
187 BUG();
188 }
189
190 if (mips_cpc_present()) {
191 for_each_cpu(cpu, mask) {
192 core = cpu_data[cpu].core;
193
194 if (core == current_cpu_data.core)
195 continue;
196
197 while (!cpumask_test_cpu(cpu, &cpu_coherent_mask)) {
198 mips_cm_lock_other(core, 0);
199 mips_cpc_lock_other(core);
200 write_cpc_co_cmd(CPC_Cx_CMD_PWRUP);
201 mips_cpc_unlock_other();
202 mips_cm_unlock_other();
203 }
204 }
205 }
206
207 local_irq_restore(flags);
208 }
209
210
ipi_resched_interrupt(int irq,void * dev_id)211 static irqreturn_t ipi_resched_interrupt(int irq, void *dev_id)
212 {
213 scheduler_ipi();
214
215 return IRQ_HANDLED;
216 }
217
ipi_call_interrupt(int irq,void * dev_id)218 static irqreturn_t ipi_call_interrupt(int irq, void *dev_id)
219 {
220 generic_smp_call_function_interrupt();
221
222 return IRQ_HANDLED;
223 }
224
225 static struct irqaction irq_resched = {
226 .handler = ipi_resched_interrupt,
227 .flags = IRQF_PERCPU,
228 .name = "IPI resched"
229 };
230
231 static struct irqaction irq_call = {
232 .handler = ipi_call_interrupt,
233 .flags = IRQF_PERCPU,
234 .name = "IPI call"
235 };
236
smp_ipi_init_one(unsigned int virq,struct irqaction * action)237 static void smp_ipi_init_one(unsigned int virq,
238 struct irqaction *action)
239 {
240 int ret;
241
242 irq_set_handler(virq, handle_percpu_irq);
243 ret = setup_irq(virq, action);
244 BUG_ON(ret);
245 }
246
247 static unsigned int call_virq, sched_virq;
248
mips_smp_ipi_allocate(const struct cpumask * mask)249 int mips_smp_ipi_allocate(const struct cpumask *mask)
250 {
251 int virq;
252 struct irq_domain *ipidomain;
253 struct device_node *node;
254
255 node = of_irq_find_parent(of_root);
256 ipidomain = irq_find_matching_host(node, DOMAIN_BUS_IPI);
257
258 /*
259 * Some platforms have half DT setup. So if we found irq node but
260 * didn't find an ipidomain, try to search for one that is not in the
261 * DT.
262 */
263 if (node && !ipidomain)
264 ipidomain = irq_find_matching_host(NULL, DOMAIN_BUS_IPI);
265
266 /*
267 * There are systems which only use IPI domains some of the time,
268 * depending upon configuration we don't know until runtime. An
269 * example is Malta where we may compile in support for GIC & the
270 * MT ASE, but run on a system which has multiple VPEs in a single
271 * core and doesn't include a GIC. Until all IPI implementations
272 * have been converted to use IPI domains the best we can do here
273 * is to return & hope some other code sets up the IPIs.
274 */
275 if (!ipidomain)
276 return 0;
277
278 virq = irq_reserve_ipi(ipidomain, mask);
279 BUG_ON(!virq);
280 if (!call_virq)
281 call_virq = virq;
282
283 virq = irq_reserve_ipi(ipidomain, mask);
284 BUG_ON(!virq);
285 if (!sched_virq)
286 sched_virq = virq;
287
288 if (irq_domain_is_ipi_per_cpu(ipidomain)) {
289 int cpu;
290
291 for_each_cpu(cpu, mask) {
292 smp_ipi_init_one(call_virq + cpu, &irq_call);
293 smp_ipi_init_one(sched_virq + cpu, &irq_resched);
294 }
295 } else {
296 smp_ipi_init_one(call_virq, &irq_call);
297 smp_ipi_init_one(sched_virq, &irq_resched);
298 }
299
300 return 0;
301 }
302
mips_smp_ipi_free(const struct cpumask * mask)303 int mips_smp_ipi_free(const struct cpumask *mask)
304 {
305 struct irq_domain *ipidomain;
306 struct device_node *node;
307
308 node = of_irq_find_parent(of_root);
309 ipidomain = irq_find_matching_host(node, DOMAIN_BUS_IPI);
310
311 /*
312 * Some platforms have half DT setup. So if we found irq node but
313 * didn't find an ipidomain, try to search for one that is not in the
314 * DT.
315 */
316 if (node && !ipidomain)
317 ipidomain = irq_find_matching_host(NULL, DOMAIN_BUS_IPI);
318
319 BUG_ON(!ipidomain);
320
321 if (irq_domain_is_ipi_per_cpu(ipidomain)) {
322 int cpu;
323
324 for_each_cpu(cpu, mask) {
325 remove_irq(call_virq + cpu, &irq_call);
326 remove_irq(sched_virq + cpu, &irq_resched);
327 }
328 }
329 irq_destroy_ipi(call_virq, mask);
330 irq_destroy_ipi(sched_virq, mask);
331 return 0;
332 }
333
334
mips_smp_ipi_init(void)335 static int __init mips_smp_ipi_init(void)
336 {
337 mips_smp_ipi_allocate(cpu_possible_mask);
338
339 call_desc = irq_to_desc(call_virq);
340 sched_desc = irq_to_desc(sched_virq);
341
342 return 0;
343 }
344 early_initcall(mips_smp_ipi_init);
345 #endif
346
347 /*
348 * First C code run on the secondary CPUs after being started up by
349 * the master.
350 */
start_secondary(void)351 asmlinkage void start_secondary(void)
352 {
353 unsigned int cpu;
354
355 cpu_probe();
356 per_cpu_trap_init(false);
357 mips_clockevent_init();
358 mp_ops->init_secondary();
359 cpu_report();
360 maar_init();
361
362 /*
363 * XXX parity protection should be folded in here when it's converted
364 * to an option instead of something based on .cputype
365 */
366
367 calibrate_delay();
368 preempt_disable();
369 cpu = smp_processor_id();
370 cpu_data[cpu].udelay_val = loops_per_jiffy;
371
372 cpumask_set_cpu(cpu, &cpu_coherent_mask);
373 notify_cpu_starting(cpu);
374
375 /* Notify boot CPU that we're starting & ready to sync counters */
376 complete(&cpu_starting);
377
378 synchronise_count_slave(cpu);
379
380 /* The CPU is running and counters synchronised, now mark it online */
381 set_cpu_online(cpu, true);
382
383 set_cpu_sibling_map(cpu);
384 set_cpu_core_map(cpu);
385
386 calculate_cpu_foreign_map();
387
388 /*
389 * Notify boot CPU that we're up & online and it can safely return
390 * from __cpu_up
391 */
392 complete(&cpu_running);
393
394 /*
395 * irq will be enabled in ->smp_finish(), enabling it too early
396 * is dangerous.
397 */
398 WARN_ON_ONCE(!irqs_disabled());
399 mp_ops->smp_finish();
400
401 cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
402 }
403
stop_this_cpu(void * dummy)404 static void stop_this_cpu(void *dummy)
405 {
406 /*
407 * Remove this CPU:
408 */
409
410 set_cpu_online(smp_processor_id(), false);
411 calculate_cpu_foreign_map();
412 local_irq_disable();
413 while (1);
414 }
415
smp_send_stop(void)416 void smp_send_stop(void)
417 {
418 smp_call_function(stop_this_cpu, NULL, 0);
419 }
420
smp_cpus_done(unsigned int max_cpus)421 void __init smp_cpus_done(unsigned int max_cpus)
422 {
423 }
424
425 /* called from main before smp_init() */
smp_prepare_cpus(unsigned int max_cpus)426 void __init smp_prepare_cpus(unsigned int max_cpus)
427 {
428 init_new_context(current, &init_mm);
429 current_thread_info()->cpu = 0;
430 mp_ops->prepare_cpus(max_cpus);
431 set_cpu_sibling_map(0);
432 set_cpu_core_map(0);
433 calculate_cpu_foreign_map();
434 #ifndef CONFIG_HOTPLUG_CPU
435 init_cpu_present(cpu_possible_mask);
436 #endif
437 cpumask_copy(&cpu_coherent_mask, cpu_possible_mask);
438 }
439
440 /* preload SMP state for boot cpu */
smp_prepare_boot_cpu(void)441 void smp_prepare_boot_cpu(void)
442 {
443 set_cpu_possible(0, true);
444 set_cpu_online(0, true);
445 }
446
__cpu_up(unsigned int cpu,struct task_struct * tidle)447 int __cpu_up(unsigned int cpu, struct task_struct *tidle)
448 {
449 mp_ops->boot_secondary(cpu, tidle);
450
451 /* Wait for CPU to start and be ready to sync counters */
452 if (!wait_for_completion_timeout(&cpu_starting,
453 msecs_to_jiffies(1000))) {
454 pr_crit("CPU%u: failed to start\n", cpu);
455 return -EIO;
456 }
457
458 synchronise_count_master(cpu);
459
460 /* Wait for CPU to finish startup & mark itself online before return */
461 wait_for_completion(&cpu_running);
462 return 0;
463 }
464
465 /* Not really SMP stuff ... */
setup_profiling_timer(unsigned int multiplier)466 int setup_profiling_timer(unsigned int multiplier)
467 {
468 return 0;
469 }
470
flush_tlb_all_ipi(void * info)471 static void flush_tlb_all_ipi(void *info)
472 {
473 local_flush_tlb_all();
474 }
475
flush_tlb_all(void)476 void flush_tlb_all(void)
477 {
478 on_each_cpu(flush_tlb_all_ipi, NULL, 1);
479 }
480
flush_tlb_mm_ipi(void * mm)481 static void flush_tlb_mm_ipi(void *mm)
482 {
483 local_flush_tlb_mm((struct mm_struct *)mm);
484 }
485
486 /*
487 * Special Variant of smp_call_function for use by TLB functions:
488 *
489 * o No return value
490 * o collapses to normal function call on UP kernels
491 * o collapses to normal function call on systems with a single shared
492 * primary cache.
493 */
smp_on_other_tlbs(void (* func)(void * info),void * info)494 static inline void smp_on_other_tlbs(void (*func) (void *info), void *info)
495 {
496 smp_call_function(func, info, 1);
497 }
498
smp_on_each_tlb(void (* func)(void * info),void * info)499 static inline void smp_on_each_tlb(void (*func) (void *info), void *info)
500 {
501 preempt_disable();
502
503 smp_on_other_tlbs(func, info);
504 func(info);
505
506 preempt_enable();
507 }
508
509 /*
510 * The following tlb flush calls are invoked when old translations are
511 * being torn down, or pte attributes are changing. For single threaded
512 * address spaces, a new context is obtained on the current cpu, and tlb
513 * context on other cpus are invalidated to force a new context allocation
514 * at switch_mm time, should the mm ever be used on other cpus. For
515 * multithreaded address spaces, intercpu interrupts have to be sent.
516 * Another case where intercpu interrupts are required is when the target
517 * mm might be active on another cpu (eg debuggers doing the flushes on
518 * behalf of debugees, kswapd stealing pages from another process etc).
519 * Kanoj 07/00.
520 */
521
flush_tlb_mm(struct mm_struct * mm)522 void flush_tlb_mm(struct mm_struct *mm)
523 {
524 preempt_disable();
525
526 if ((atomic_read(&mm->mm_users) != 1) || (current->mm != mm)) {
527 smp_on_other_tlbs(flush_tlb_mm_ipi, mm);
528 } else {
529 unsigned int cpu;
530
531 for_each_online_cpu(cpu) {
532 if (cpu != smp_processor_id() && cpu_context(cpu, mm))
533 cpu_context(cpu, mm) = 0;
534 }
535 }
536 local_flush_tlb_mm(mm);
537
538 preempt_enable();
539 }
540
541 struct flush_tlb_data {
542 struct vm_area_struct *vma;
543 unsigned long addr1;
544 unsigned long addr2;
545 };
546
flush_tlb_range_ipi(void * info)547 static void flush_tlb_range_ipi(void *info)
548 {
549 struct flush_tlb_data *fd = info;
550
551 local_flush_tlb_range(fd->vma, fd->addr1, fd->addr2);
552 }
553
flush_tlb_range(struct vm_area_struct * vma,unsigned long start,unsigned long end)554 void flush_tlb_range(struct vm_area_struct *vma, unsigned long start, unsigned long end)
555 {
556 struct mm_struct *mm = vma->vm_mm;
557
558 preempt_disable();
559 if ((atomic_read(&mm->mm_users) != 1) || (current->mm != mm)) {
560 struct flush_tlb_data fd = {
561 .vma = vma,
562 .addr1 = start,
563 .addr2 = end,
564 };
565
566 smp_on_other_tlbs(flush_tlb_range_ipi, &fd);
567 } else {
568 unsigned int cpu;
569 int exec = vma->vm_flags & VM_EXEC;
570
571 for_each_online_cpu(cpu) {
572 /*
573 * flush_cache_range() will only fully flush icache if
574 * the VMA is executable, otherwise we must invalidate
575 * ASID without it appearing to has_valid_asid() as if
576 * mm has been completely unused by that CPU.
577 */
578 if (cpu != smp_processor_id() && cpu_context(cpu, mm))
579 cpu_context(cpu, mm) = !exec;
580 }
581 }
582 local_flush_tlb_range(vma, start, end);
583 preempt_enable();
584 }
585
flush_tlb_kernel_range_ipi(void * info)586 static void flush_tlb_kernel_range_ipi(void *info)
587 {
588 struct flush_tlb_data *fd = info;
589
590 local_flush_tlb_kernel_range(fd->addr1, fd->addr2);
591 }
592
flush_tlb_kernel_range(unsigned long start,unsigned long end)593 void flush_tlb_kernel_range(unsigned long start, unsigned long end)
594 {
595 struct flush_tlb_data fd = {
596 .addr1 = start,
597 .addr2 = end,
598 };
599
600 on_each_cpu(flush_tlb_kernel_range_ipi, &fd, 1);
601 }
602
flush_tlb_page_ipi(void * info)603 static void flush_tlb_page_ipi(void *info)
604 {
605 struct flush_tlb_data *fd = info;
606
607 local_flush_tlb_page(fd->vma, fd->addr1);
608 }
609
flush_tlb_page(struct vm_area_struct * vma,unsigned long page)610 void flush_tlb_page(struct vm_area_struct *vma, unsigned long page)
611 {
612 preempt_disable();
613 if ((atomic_read(&vma->vm_mm->mm_users) != 1) || (current->mm != vma->vm_mm)) {
614 struct flush_tlb_data fd = {
615 .vma = vma,
616 .addr1 = page,
617 };
618
619 smp_on_other_tlbs(flush_tlb_page_ipi, &fd);
620 } else {
621 unsigned int cpu;
622
623 for_each_online_cpu(cpu) {
624 /*
625 * flush_cache_page() only does partial flushes, so
626 * invalidate ASID without it appearing to
627 * has_valid_asid() as if mm has been completely unused
628 * by that CPU.
629 */
630 if (cpu != smp_processor_id() && cpu_context(cpu, vma->vm_mm))
631 cpu_context(cpu, vma->vm_mm) = 1;
632 }
633 }
634 local_flush_tlb_page(vma, page);
635 preempt_enable();
636 }
637
flush_tlb_one_ipi(void * info)638 static void flush_tlb_one_ipi(void *info)
639 {
640 unsigned long vaddr = (unsigned long) info;
641
642 local_flush_tlb_one(vaddr);
643 }
644
flush_tlb_one(unsigned long vaddr)645 void flush_tlb_one(unsigned long vaddr)
646 {
647 smp_on_each_tlb(flush_tlb_one_ipi, (void *) vaddr);
648 }
649
650 EXPORT_SYMBOL(flush_tlb_page);
651 EXPORT_SYMBOL(flush_tlb_one);
652
653 #if defined(CONFIG_KEXEC)
654 void (*dump_ipi_function_ptr)(void *) = NULL;
dump_send_ipi(void (* dump_ipi_callback)(void *))655 void dump_send_ipi(void (*dump_ipi_callback)(void *))
656 {
657 int i;
658 int cpu = smp_processor_id();
659
660 dump_ipi_function_ptr = dump_ipi_callback;
661 smp_mb();
662 for_each_online_cpu(i)
663 if (i != cpu)
664 mp_ops->send_ipi_single(i, SMP_DUMP);
665
666 }
667 EXPORT_SYMBOL(dump_send_ipi);
668 #endif
669
670 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
671
672 static DEFINE_PER_CPU(atomic_t, tick_broadcast_count);
673 static DEFINE_PER_CPU(struct call_single_data, tick_broadcast_csd);
674
tick_broadcast(const struct cpumask * mask)675 void tick_broadcast(const struct cpumask *mask)
676 {
677 atomic_t *count;
678 struct call_single_data *csd;
679 int cpu;
680
681 for_each_cpu(cpu, mask) {
682 count = &per_cpu(tick_broadcast_count, cpu);
683 csd = &per_cpu(tick_broadcast_csd, cpu);
684
685 if (atomic_inc_return(count) == 1)
686 smp_call_function_single_async(cpu, csd);
687 }
688 }
689
tick_broadcast_callee(void * info)690 static void tick_broadcast_callee(void *info)
691 {
692 int cpu = smp_processor_id();
693 tick_receive_broadcast();
694 atomic_set(&per_cpu(tick_broadcast_count, cpu), 0);
695 }
696
tick_broadcast_init(void)697 static int __init tick_broadcast_init(void)
698 {
699 struct call_single_data *csd;
700 int cpu;
701
702 for (cpu = 0; cpu < NR_CPUS; cpu++) {
703 csd = &per_cpu(tick_broadcast_csd, cpu);
704 csd->func = tick_broadcast_callee;
705 }
706
707 return 0;
708 }
709 early_initcall(tick_broadcast_init);
710
711 #endif /* CONFIG_GENERIC_CLOCKEVENTS_BROADCAST */
712