blob: 344e52b16c8cd4234b523547d07a8b6ff9106bd6 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/arch/arm/kernel/smp.c
3 *
4 * Copyright (C) 2002 ARM Limited, All Rights Reserved.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
Russell Kingc97d4862006-10-25 13:59:16 +010010#include <linux/module.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070011#include <linux/delay.h>
12#include <linux/init.h>
13#include <linux/spinlock.h>
14#include <linux/sched.h>
15#include <linux/interrupt.h>
16#include <linux/cache.h>
17#include <linux/profile.h>
18#include <linux/errno.h>
Rabin Vincent61b5cb12010-10-07 20:51:58 +053019#include <linux/ftrace.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070020#include <linux/mm.h>
Alexey Dobriyan4e950f62007-07-30 02:36:13 +040021#include <linux/err.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070022#include <linux/cpu.h>
23#include <linux/smp.h>
24#include <linux/seq_file.h>
Russell Kingc97d4862006-10-25 13:59:16 +010025#include <linux/irq.h>
Russell Kingbc282482009-05-17 18:58:34 +010026#include <linux/percpu.h>
27#include <linux/clockchips.h>
Russell King3c030be2010-11-30 11:07:35 +000028#include <linux/completion.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070029
30#include <asm/atomic.h>
31#include <asm/cacheflush.h>
32#include <asm/cpu.h>
Russell King42578c82009-06-11 15:35:00 +010033#include <asm/cputype.h>
Russell Kinge65f38e2005-06-18 09:33:31 +010034#include <asm/mmu_context.h>
35#include <asm/pgtable.h>
36#include <asm/pgalloc.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070037#include <asm/processor.h>
Russell King37b05b62010-10-01 15:38:24 +010038#include <asm/sections.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070039#include <asm/tlbflush.h>
40#include <asm/ptrace.h>
Russell Kingbc282482009-05-17 18:58:34 +010041#include <asm/localtimer.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070042
43/*
Russell Kinge65f38e2005-06-18 09:33:31 +010044 * as from 2.5, kernels no longer have an init_tasks structure
45 * so we need some other way of telling a new secondary core
46 * where to place its SVC stack
47 */
48struct secondary_data secondary_data;
49
Linus Torvalds1da177e2005-04-16 15:20:36 -070050enum ipi_msg_type {
Russell King24480d92010-11-15 09:54:18 +000051 IPI_TIMER = 2,
Linus Torvalds1da177e2005-04-16 15:20:36 -070052 IPI_RESCHEDULE,
53 IPI_CALL_FUNC,
Jens Axboef6dd9fa2008-06-10 20:48:30 +020054 IPI_CALL_FUNC_SINGLE,
Linus Torvalds1da177e2005-04-16 15:20:36 -070055 IPI_CPU_STOP,
56};
57
Russell Kingbd6f68a2005-07-17 21:35:41 +010058int __cpuinit __cpu_up(unsigned int cpu)
Linus Torvalds1da177e2005-04-16 15:20:36 -070059{
Russell King71f512e82005-11-02 21:51:40 +000060 struct cpuinfo_arm *ci = &per_cpu(cpu_data, cpu);
61 struct task_struct *idle = ci->idle;
Russell Kinge65f38e2005-06-18 09:33:31 +010062 pgd_t *pgd;
Linus Torvalds1da177e2005-04-16 15:20:36 -070063 int ret;
64
65 /*
Russell King71f512e82005-11-02 21:51:40 +000066 * Spawn a new process manually, if not already done.
67 * Grab a pointer to its task struct so we can mess with it
Linus Torvalds1da177e2005-04-16 15:20:36 -070068 */
Russell King71f512e82005-11-02 21:51:40 +000069 if (!idle) {
70 idle = fork_idle(cpu);
71 if (IS_ERR(idle)) {
72 printk(KERN_ERR "CPU%u: fork() failed\n", cpu);
73 return PTR_ERR(idle);
74 }
75 ci->idle = idle;
Santosh Shilimkar13ea9cc2010-04-30 06:51:20 +010076 } else {
77 /*
78 * Since this idle thread is being re-used, call
79 * init_idle() to reinitialize the thread structure.
80 */
81 init_idle(idle, cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -070082 }
83
84 /*
Russell Kinge65f38e2005-06-18 09:33:31 +010085 * Allocate initial page tables to allow the new CPU to
86 * enable the MMU safely. This essentially means a set
87 * of our "standard" page tables, with the addition of
88 * a 1:1 mapping for the physical address of the kernel.
89 */
90 pgd = pgd_alloc(&init_mm);
Russell King37b05b62010-10-01 15:38:24 +010091 if (!pgd)
92 return -ENOMEM;
93
94 if (PHYS_OFFSET != PAGE_OFFSET) {
95#ifndef CONFIG_HOTPLUG_CPU
96 identity_mapping_add(pgd, __pa(__init_begin), __pa(__init_end));
97#endif
98 identity_mapping_add(pgd, __pa(_stext), __pa(_etext));
99 identity_mapping_add(pgd, __pa(_sdata), __pa(_edata));
100 }
Russell Kinge65f38e2005-06-18 09:33:31 +0100101
102 /*
103 * We need to tell the secondary core where to find
104 * its stack and the page tables.
105 */
Al Viro32d39a92006-01-12 01:05:58 -0800106 secondary_data.stack = task_stack_page(idle) + THREAD_START_SP;
Russell Kinge65f38e2005-06-18 09:33:31 +0100107 secondary_data.pgdir = virt_to_phys(pgd);
Catalin Marinasd4279582011-05-26 11:22:44 +0100108 secondary_data.swapper_pg_dir = virt_to_phys(swapper_pg_dir);
Russell King10272472010-02-12 14:36:24 +0000109 __cpuc_flush_dcache_area(&secondary_data, sizeof(secondary_data));
110 outer_clean_range(__pa(&secondary_data), __pa(&secondary_data + 1));
Russell Kinge65f38e2005-06-18 09:33:31 +0100111
112 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700113 * Now bring the CPU into our world.
114 */
115 ret = boot_secondary(cpu, idle);
Russell Kinge65f38e2005-06-18 09:33:31 +0100116 if (ret == 0) {
117 unsigned long timeout;
118
119 /*
120 * CPU was successfully started, wait for it
121 * to come online or time out.
122 */
123 timeout = jiffies + HZ;
124 while (time_before(jiffies, timeout)) {
125 if (cpu_online(cpu))
126 break;
127
128 udelay(10);
129 barrier();
130 }
131
Russell King58613cd2010-12-18 12:34:39 +0000132 if (!cpu_online(cpu)) {
133 pr_crit("CPU%u: failed to come online\n", cpu);
Russell Kinge65f38e2005-06-18 09:33:31 +0100134 ret = -EIO;
Russell King58613cd2010-12-18 12:34:39 +0000135 }
136 } else {
137 pr_err("CPU%u: failed to boot: %d\n", cpu, ret);
Russell Kinge65f38e2005-06-18 09:33:31 +0100138 }
139
Russell King5d430452005-11-08 10:44:46 +0000140 secondary_data.stack = NULL;
Russell Kinge65f38e2005-06-18 09:33:31 +0100141 secondary_data.pgdir = 0;
142
Russell King37b05b62010-10-01 15:38:24 +0100143 if (PHYS_OFFSET != PAGE_OFFSET) {
144#ifndef CONFIG_HOTPLUG_CPU
145 identity_mapping_del(pgd, __pa(__init_begin), __pa(__init_end));
146#endif
147 identity_mapping_del(pgd, __pa(_stext), __pa(_etext));
148 identity_mapping_del(pgd, __pa(_sdata), __pa(_edata));
149 }
150
Benjamin Herrenschmidt5e541972008-02-04 22:29:14 -0800151 pgd_free(&init_mm, pgd);
Russell Kinge65f38e2005-06-18 09:33:31 +0100152
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153 return ret;
154}
155
Russell Kinga054a812005-11-02 22:24:33 +0000156#ifdef CONFIG_HOTPLUG_CPU
Russell King10034aa2010-12-20 14:28:02 +0000157static void percpu_timer_stop(void);
158
Russell Kinga054a812005-11-02 22:24:33 +0000159/*
160 * __cpu_disable runs on the processor to be shutdown.
161 */
Russell King90140c32009-09-27 21:04:48 +0100162int __cpu_disable(void)
Russell Kinga054a812005-11-02 22:24:33 +0000163{
164 unsigned int cpu = smp_processor_id();
165 struct task_struct *p;
166 int ret;
167
Russell King8e2a43f2010-05-15 10:18:05 +0100168 ret = platform_cpu_disable(cpu);
Russell Kinga054a812005-11-02 22:24:33 +0000169 if (ret)
170 return ret;
171
172 /*
173 * Take this CPU offline. Once we clear this, we can't return,
174 * and we must not schedule until we're ready to give up the cpu.
175 */
Russell Kinge03cdad2009-05-28 14:16:52 +0100176 set_cpu_online(cpu, false);
Russell Kinga054a812005-11-02 22:24:33 +0000177
178 /*
179 * OK - migrate IRQs away from this CPU
180 */
181 migrate_irqs();
182
183 /*
Russell King37ee16a2005-11-08 19:08:05 +0000184 * Stop the local timer for this CPU.
185 */
Russell King10034aa2010-12-20 14:28:02 +0000186 percpu_timer_stop();
Russell King37ee16a2005-11-08 19:08:05 +0000187
188 /*
Russell Kinga054a812005-11-02 22:24:33 +0000189 * Flush user cache and TLB mappings, and then remove this CPU
190 * from the vm mask set of all processes.
191 */
192 flush_cache_all();
193 local_flush_tlb_all();
194
195 read_lock(&tasklist_lock);
196 for_each_process(p) {
197 if (p->mm)
Rusty Russell56f8ba82009-09-24 09:34:49 -0600198 cpumask_clear_cpu(cpu, mm_cpumask(p->mm));
Russell Kinga054a812005-11-02 22:24:33 +0000199 }
200 read_unlock(&tasklist_lock);
201
202 return 0;
203}
204
Russell King3c030be2010-11-30 11:07:35 +0000205static DECLARE_COMPLETION(cpu_died);
206
Russell Kinga054a812005-11-02 22:24:33 +0000207/*
208 * called on the thread which is asking for a CPU to be shutdown -
209 * waits until shutdown has completed, or it is timed out.
210 */
Russell King90140c32009-09-27 21:04:48 +0100211void __cpu_die(unsigned int cpu)
Russell Kinga054a812005-11-02 22:24:33 +0000212{
Russell King3c030be2010-11-30 11:07:35 +0000213 if (!wait_for_completion_timeout(&cpu_died, msecs_to_jiffies(5000))) {
214 pr_err("CPU%u: cpu didn't die\n", cpu);
215 return;
216 }
217 printk(KERN_NOTICE "CPU%u: shutdown\n", cpu);
218
Russell Kinga054a812005-11-02 22:24:33 +0000219 if (!platform_cpu_kill(cpu))
220 printk("CPU%u: unable to kill\n", cpu);
221}
222
223/*
224 * Called from the idle thread for the CPU which has been shutdown.
225 *
226 * Note that we disable IRQs here, but do not re-enable them
227 * before returning to the caller. This is also the behaviour
228 * of the other hotplug-cpu capable cores, so presumably coming
229 * out of idle fixes this.
230 */
Russell King90140c32009-09-27 21:04:48 +0100231void __ref cpu_die(void)
Russell Kinga054a812005-11-02 22:24:33 +0000232{
233 unsigned int cpu = smp_processor_id();
234
Russell Kinga054a812005-11-02 22:24:33 +0000235 idle_task_exit();
236
Russell Kingf36d3402010-11-30 12:21:30 +0000237 local_irq_disable();
238 mb();
239
Russell King3c030be2010-11-30 11:07:35 +0000240 /* Tell __cpu_die() that this CPU is now safe to dispose of */
241 complete(&cpu_died);
242
Russell Kinga054a812005-11-02 22:24:33 +0000243 /*
244 * actual CPU shutdown procedure is at least platform (if not
Russell King3c030be2010-11-30 11:07:35 +0000245 * CPU) specific.
Russell Kinga054a812005-11-02 22:24:33 +0000246 */
247 platform_cpu_die(cpu);
248
249 /*
250 * Do not return to the idle loop - jump back to the secondary
251 * cpu initialisation. There's some initialisation which needs
252 * to be repeated to undo the effects of taking the CPU offline.
253 */
254 __asm__("mov sp, %0\n"
Russell Kingfaabfa02010-12-20 16:58:19 +0000255 " mov fp, #0\n"
Russell Kinga054a812005-11-02 22:24:33 +0000256 " b secondary_start_kernel"
257 :
Al Viro32d39a92006-01-12 01:05:58 -0800258 : "r" (task_stack_page(current) + THREAD_SIZE - 8));
Russell Kinga054a812005-11-02 22:24:33 +0000259}
260#endif /* CONFIG_HOTPLUG_CPU */
261
Linus Torvalds1da177e2005-04-16 15:20:36 -0700262/*
Russell King05c74a62010-12-03 11:09:48 +0000263 * Called by both boot and secondaries to move global data into
264 * per-processor storage.
265 */
266static void __cpuinit smp_store_cpu_info(unsigned int cpuid)
267{
268 struct cpuinfo_arm *cpu_info = &per_cpu(cpu_data, cpuid);
269
270 cpu_info->loops_per_jiffy = loops_per_jiffy;
271}
272
273/*
Russell Kinge65f38e2005-06-18 09:33:31 +0100274 * This is the secondary CPU boot entry. We're using this CPUs
275 * idle thread stack, but a set of temporary page tables.
276 */
Russell Kingbd6f68a2005-07-17 21:35:41 +0100277asmlinkage void __cpuinit secondary_start_kernel(void)
Russell Kinge65f38e2005-06-18 09:33:31 +0100278{
279 struct mm_struct *mm = &init_mm;
Russell Kingda2660d2005-11-12 17:21:47 +0000280 unsigned int cpu = smp_processor_id();
Russell Kinge65f38e2005-06-18 09:33:31 +0100281
282 printk("CPU%u: Booted secondary processor\n", cpu);
283
284 /*
285 * All kernel threads share the same mm context; grab a
286 * reference and switch to it.
287 */
Russell Kinge65f38e2005-06-18 09:33:31 +0100288 atomic_inc(&mm->mm_count);
289 current->active_mm = mm;
Rusty Russell56f8ba82009-09-24 09:34:49 -0600290 cpumask_set_cpu(cpu, mm_cpumask(mm));
Russell Kinge65f38e2005-06-18 09:33:31 +0100291 cpu_switch_mm(mm->pgd, mm);
292 enter_lazy_tlb(mm, current);
Russell King505d7b12005-07-28 20:32:47 +0100293 local_flush_tlb_all();
Russell Kinge65f38e2005-06-18 09:33:31 +0100294
295 cpu_init();
Nick Piggin5bfb5d62005-11-08 21:39:01 -0800296 preempt_disable();
Russell King2c0136d2010-12-03 15:00:49 +0000297 trace_hardirqs_off();
Russell Kinge65f38e2005-06-18 09:33:31 +0100298
299 /*
300 * Give the platform a chance to do its own initialisation.
301 */
302 platform_secondary_init(cpu);
303
304 /*
305 * Enable local interrupts.
306 */
Manfred Spraule545a612008-09-07 16:57:22 +0200307 notify_cpu_starting(cpu);
Russell Kinge65f38e2005-06-18 09:33:31 +0100308 local_irq_enable();
309 local_fiq_enable();
310
Catalin Marinasa8655e82008-02-04 17:30:57 +0100311 /*
Russell Kingbc282482009-05-17 18:58:34 +0100312 * Setup the percpu timer for this CPU.
Catalin Marinasa8655e82008-02-04 17:30:57 +0100313 */
Russell Kingbc282482009-05-17 18:58:34 +0100314 percpu_timer_setup();
Catalin Marinasa8655e82008-02-04 17:30:57 +0100315
Russell Kinge65f38e2005-06-18 09:33:31 +0100316 calibrate_delay();
317
318 smp_store_cpu_info(cpu);
319
320 /*
321 * OK, now it's safe to let the boot CPU continue
322 */
Russell Kinge03cdad2009-05-28 14:16:52 +0100323 set_cpu_online(cpu, true);
Russell Kinge65f38e2005-06-18 09:33:31 +0100324
325 /*
326 * OK, it's off to the idle thread for us
327 */
328 cpu_idle();
329}
330
Linus Torvalds1da177e2005-04-16 15:20:36 -0700331void __init smp_cpus_done(unsigned int max_cpus)
332{
333 int cpu;
334 unsigned long bogosum = 0;
335
336 for_each_online_cpu(cpu)
337 bogosum += per_cpu(cpu_data, cpu).loops_per_jiffy;
338
339 printk(KERN_INFO "SMP: Total of %d processors activated "
340 "(%lu.%02lu BogoMIPS).\n",
341 num_online_cpus(),
342 bogosum / (500000/HZ),
343 (bogosum / (5000/HZ)) % 100);
344}
345
346void __init smp_prepare_boot_cpu(void)
347{
348 unsigned int cpu = smp_processor_id();
349
Russell King71f512e82005-11-02 21:51:40 +0000350 per_cpu(cpu_data, cpu).idle = current;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700351}
352
Russell King05c74a62010-12-03 11:09:48 +0000353void __init smp_prepare_cpus(unsigned int max_cpus)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354{
Russell King05c74a62010-12-03 11:09:48 +0000355 unsigned int ncores = num_possible_cpus();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700356
Russell King05c74a62010-12-03 11:09:48 +0000357 smp_store_cpu_info(smp_processor_id());
Linus Torvalds1da177e2005-04-16 15:20:36 -0700358
359 /*
Russell King05c74a62010-12-03 11:09:48 +0000360 * are we trying to boot more cores than exist?
Linus Torvalds1da177e2005-04-16 15:20:36 -0700361 */
Russell King05c74a62010-12-03 11:09:48 +0000362 if (max_cpus > ncores)
363 max_cpus = ncores;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700364
Russell King05c74a62010-12-03 11:09:48 +0000365 if (max_cpus > 1) {
366 /*
367 * Enable the local timer or broadcast device for the
368 * boot CPU, but only if we have more than one CPU.
369 */
370 percpu_timer_setup();
371
372 /*
373 * Initialise the SCU if there are more than one CPU
374 * and let them know where to start.
375 */
376 platform_smp_prepare_cpus(max_cpus);
377 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700378}
379
Russell King0f7b3322011-04-03 13:01:30 +0100380static void (*smp_cross_call)(const struct cpumask *, unsigned int);
381
382void __init set_smp_cross_call(void (*fn)(const struct cpumask *, unsigned int))
383{
384 smp_cross_call = fn;
385}
386
Russell King82668102009-05-17 16:20:18 +0100387void arch_send_call_function_ipi_mask(const struct cpumask *mask)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388{
Russell Kinge3fbb082010-12-20 14:47:19 +0000389 smp_cross_call(mask, IPI_CALL_FUNC);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700390}
391
Jens Axboef6dd9fa2008-06-10 20:48:30 +0200392void arch_send_call_function_single_ipi(int cpu)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700393{
Russell Kinge3fbb082010-12-20 14:47:19 +0000394 smp_cross_call(cpumask_of(cpu), IPI_CALL_FUNC_SINGLE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700395}
Catalin Marinas3e459992008-02-04 17:28:56 +0100396
Russell King4a88abd2010-11-15 14:40:29 +0000397static const char *ipi_types[NR_IPI] = {
398#define S(x,s) [x - IPI_TIMER] = s
399 S(IPI_TIMER, "Timer broadcast interrupts"),
400 S(IPI_RESCHEDULE, "Rescheduling interrupts"),
401 S(IPI_CALL_FUNC, "Function call interrupts"),
402 S(IPI_CALL_FUNC_SINGLE, "Single function call interrupts"),
403 S(IPI_CPU_STOP, "CPU stop interrupts"),
404};
405
Russell Kingf13cd412010-11-15 14:33:51 +0000406void show_ipi_list(struct seq_file *p, int prec)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407{
Russell King4a88abd2010-11-15 14:40:29 +0000408 unsigned int cpu, i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409
Russell King4a88abd2010-11-15 14:40:29 +0000410 for (i = 0; i < NR_IPI; i++) {
411 seq_printf(p, "%*s%u: ", prec - 1, "IPI", i);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700412
Russell King4a88abd2010-11-15 14:40:29 +0000413 for_each_present_cpu(cpu)
414 seq_printf(p, "%10u ",
415 __get_irq_stat(cpu, ipi_irqs[i]));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700416
Russell King4a88abd2010-11-15 14:40:29 +0000417 seq_printf(p, " %s\n", ipi_types[i]);
418 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700419}
420
Russell Kingb54992f2010-11-15 14:46:46 +0000421u64 smp_irq_stat_cpu(unsigned int cpu)
Russell King37ee16a2005-11-08 19:08:05 +0000422{
Russell Kingb54992f2010-11-15 14:46:46 +0000423 u64 sum = 0;
424 int i;
Russell King37ee16a2005-11-08 19:08:05 +0000425
Russell Kingb54992f2010-11-15 14:46:46 +0000426 for (i = 0; i < NR_IPI; i++)
427 sum += __get_irq_stat(cpu, ipi_irqs[i]);
Russell King37ee16a2005-11-08 19:08:05 +0000428
Russell Kingb54992f2010-11-15 14:46:46 +0000429#ifdef CONFIG_LOCAL_TIMERS
430 sum += __get_irq_stat(cpu, local_timer_irqs);
431#endif
Russell King37ee16a2005-11-08 19:08:05 +0000432
Russell Kingb54992f2010-11-15 14:46:46 +0000433 return sum;
Russell King37ee16a2005-11-08 19:08:05 +0000434}
435
Russell Kingbc282482009-05-17 18:58:34 +0100436/*
437 * Timer (local or broadcast) support
438 */
439static DEFINE_PER_CPU(struct clock_event_device, percpu_clockevent);
440
Russell Kingc97d4862006-10-25 13:59:16 +0100441static void ipi_timer(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700442{
Russell Kingbc282482009-05-17 18:58:34 +0100443 struct clock_event_device *evt = &__get_cpu_var(percpu_clockevent);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700444 irq_enter();
Russell Kingbc282482009-05-17 18:58:34 +0100445 evt->event_handler(evt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700446 irq_exit();
447}
448
Russell King37ee16a2005-11-08 19:08:05 +0000449#ifdef CONFIG_LOCAL_TIMERS
Rabin Vincent61b5cb12010-10-07 20:51:58 +0530450asmlinkage void __exception_irq_entry do_local_timer(struct pt_regs *regs)
Russell King37ee16a2005-11-08 19:08:05 +0000451{
Russell Kingc97d4862006-10-25 13:59:16 +0100452 struct pt_regs *old_regs = set_irq_regs(regs);
Russell King37ee16a2005-11-08 19:08:05 +0000453 int cpu = smp_processor_id();
454
455 if (local_timer_ack()) {
Russell King46c48f22010-11-15 14:15:03 +0000456 __inc_irq_stat(cpu, local_timer_irqs);
Russell Kingc97d4862006-10-25 13:59:16 +0100457 ipi_timer();
Russell King37ee16a2005-11-08 19:08:05 +0000458 }
Russell Kingc97d4862006-10-25 13:59:16 +0100459
460 set_irq_regs(old_regs);
Russell King37ee16a2005-11-08 19:08:05 +0000461}
Russell Kingec405ea2010-11-15 13:38:06 +0000462
Russell Kingf13cd412010-11-15 14:33:51 +0000463void show_local_irqs(struct seq_file *p, int prec)
Russell Kingec405ea2010-11-15 13:38:06 +0000464{
465 unsigned int cpu;
466
Russell Kingf13cd412010-11-15 14:33:51 +0000467 seq_printf(p, "%*s: ", prec, "LOC");
Russell Kingec405ea2010-11-15 13:38:06 +0000468
469 for_each_present_cpu(cpu)
Russell King46c48f22010-11-15 14:15:03 +0000470 seq_printf(p, "%10u ", __get_irq_stat(cpu, local_timer_irqs));
Russell Kingec405ea2010-11-15 13:38:06 +0000471
Russell Kingf13cd412010-11-15 14:33:51 +0000472 seq_printf(p, " Local timer interrupts\n");
Russell Kingec405ea2010-11-15 13:38:06 +0000473}
Russell King37ee16a2005-11-08 19:08:05 +0000474#endif
475
Russell Kingbc282482009-05-17 18:58:34 +0100476#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
477static void smp_timer_broadcast(const struct cpumask *mask)
478{
Russell Kinge3fbb082010-12-20 14:47:19 +0000479 smp_cross_call(mask, IPI_TIMER);
Russell Kingbc282482009-05-17 18:58:34 +0100480}
Russell King5388a6b2010-07-26 13:19:43 +0100481#else
482#define smp_timer_broadcast NULL
483#endif
Russell Kingbc282482009-05-17 18:58:34 +0100484
485static void broadcast_timer_set_mode(enum clock_event_mode mode,
486 struct clock_event_device *evt)
487{
488}
489
Stephen Boyda8d25182011-04-27 01:34:27 +0100490static void __cpuinit broadcast_timer_setup(struct clock_event_device *evt)
Russell Kingbc282482009-05-17 18:58:34 +0100491{
492 evt->name = "dummy_timer";
493 evt->features = CLOCK_EVT_FEAT_ONESHOT |
494 CLOCK_EVT_FEAT_PERIODIC |
495 CLOCK_EVT_FEAT_DUMMY;
496 evt->rating = 400;
497 evt->mult = 1;
498 evt->set_mode = broadcast_timer_set_mode;
Russell Kingbc282482009-05-17 18:58:34 +0100499
500 clockevents_register_device(evt);
501}
Russell Kingbc282482009-05-17 18:58:34 +0100502
503void __cpuinit percpu_timer_setup(void)
504{
505 unsigned int cpu = smp_processor_id();
506 struct clock_event_device *evt = &per_cpu(percpu_clockevent, cpu);
507
508 evt->cpumask = cpumask_of(cpu);
Russell King5388a6b2010-07-26 13:19:43 +0100509 evt->broadcast = smp_timer_broadcast;
Russell Kingbc282482009-05-17 18:58:34 +0100510
Santosh Shilimkaraf90f102011-02-23 18:53:15 +0100511 if (local_timer_setup(evt))
512 broadcast_timer_setup(evt);
Russell Kingbc282482009-05-17 18:58:34 +0100513}
514
Russell King10034aa2010-12-20 14:28:02 +0000515#ifdef CONFIG_HOTPLUG_CPU
516/*
517 * The generic clock events code purposely does not stop the local timer
518 * on CPU_DEAD/CPU_DEAD_FROZEN hotplug events, so we have to do it
519 * manually here.
520 */
521static void percpu_timer_stop(void)
522{
523 unsigned int cpu = smp_processor_id();
524 struct clock_event_device *evt = &per_cpu(percpu_clockevent, cpu);
525
526 evt->set_mode(CLOCK_EVT_MODE_UNUSED, evt);
527}
528#endif
529
Linus Torvalds1da177e2005-04-16 15:20:36 -0700530static DEFINE_SPINLOCK(stop_lock);
531
532/*
533 * ipi_cpu_stop - handle IPI from smp_send_stop()
534 */
535static void ipi_cpu_stop(unsigned int cpu)
536{
Russell King3d3f78d2010-07-26 13:31:27 +0100537 if (system_state == SYSTEM_BOOTING ||
538 system_state == SYSTEM_RUNNING) {
539 spin_lock(&stop_lock);
540 printk(KERN_CRIT "CPU%u: stopping\n", cpu);
541 dump_stack();
542 spin_unlock(&stop_lock);
543 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700544
Russell Kinge03cdad2009-05-28 14:16:52 +0100545 set_cpu_online(cpu, false);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700546
547 local_fiq_disable();
548 local_irq_disable();
549
550 while (1)
551 cpu_relax();
552}
553
554/*
555 * Main handler for inter-processor interrupts
Linus Torvalds1da177e2005-04-16 15:20:36 -0700556 */
Russell King40737232011-01-06 22:32:52 +0000557asmlinkage void __exception_irq_entry do_IPI(int ipinr, struct pt_regs *regs)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700558{
559 unsigned int cpu = smp_processor_id();
Russell Kingc97d4862006-10-25 13:59:16 +0100560 struct pt_regs *old_regs = set_irq_regs(regs);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700561
Russell King4a88abd2010-11-15 14:40:29 +0000562 if (ipinr >= IPI_TIMER && ipinr < IPI_TIMER + NR_IPI)
563 __inc_irq_stat(cpu, ipi_irqs[ipinr - IPI_TIMER]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700564
Russell King24480d92010-11-15 09:54:18 +0000565 switch (ipinr) {
566 case IPI_TIMER:
567 ipi_timer();
568 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700569
Russell King24480d92010-11-15 09:54:18 +0000570 case IPI_RESCHEDULE:
Peter Zijlstra184748c2011-04-05 17:23:39 +0200571 scheduler_ipi();
Russell King24480d92010-11-15 09:54:18 +0000572 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700573
Russell King24480d92010-11-15 09:54:18 +0000574 case IPI_CALL_FUNC:
575 generic_smp_call_function_interrupt();
576 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700577
Russell King24480d92010-11-15 09:54:18 +0000578 case IPI_CALL_FUNC_SINGLE:
579 generic_smp_call_function_single_interrupt();
580 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700581
Russell King24480d92010-11-15 09:54:18 +0000582 case IPI_CPU_STOP:
583 ipi_cpu_stop(cpu);
584 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700585
Russell King24480d92010-11-15 09:54:18 +0000586 default:
587 printk(KERN_CRIT "CPU%u: Unknown IPI message 0x%x\n",
588 cpu, ipinr);
589 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700590 }
Russell Kingc97d4862006-10-25 13:59:16 +0100591 set_irq_regs(old_regs);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700592}
593
594void smp_send_reschedule(int cpu)
595{
Russell Kinge3fbb082010-12-20 14:47:19 +0000596 smp_cross_call(cpumask_of(cpu), IPI_RESCHEDULE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700597}
598
Linus Torvalds1da177e2005-04-16 15:20:36 -0700599void smp_send_stop(void)
600{
Russell King28e18292010-12-02 09:53:54 +0000601 unsigned long timeout;
602
603 if (num_online_cpus() > 1) {
604 cpumask_t mask = cpu_online_map;
605 cpu_clear(smp_processor_id(), mask);
606
Russell Kinge3fbb082010-12-20 14:47:19 +0000607 smp_cross_call(&mask, IPI_CPU_STOP);
Russell King28e18292010-12-02 09:53:54 +0000608 }
609
610 /* Wait up to one second for other CPUs to stop */
611 timeout = USEC_PER_SEC;
612 while (num_online_cpus() > 1 && timeout--)
613 udelay(1);
614
615 if (num_online_cpus() > 1)
616 pr_warning("SMP: failed to stop secondary CPUs\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700617}
618
619/*
620 * not supported here
621 */
Russell King5048bcb2007-07-23 12:59:46 +0100622int setup_profiling_timer(unsigned int multiplier)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700623{
624 return -EINVAL;
625}