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/cputable.h>
45 #include <asm/system.h>
47 #include <asm/vdso_datapage.h>
54 #define DBG(fmt...) udbg_printf(fmt)
59 int smp_hw_index[NR_CPUS];
60 struct thread_info *secondary_ti;
62 cpumask_t cpu_possible_map = CPU_MASK_NONE;
63 cpumask_t cpu_online_map = CPU_MASK_NONE;
64 DEFINE_PER_CPU(cpumask_t, cpu_sibling_map) = CPU_MASK_NONE;
66 EXPORT_SYMBOL(cpu_online_map);
67 EXPORT_SYMBOL(cpu_possible_map);
68 EXPORT_PER_CPU_SYMBOL(cpu_sibling_map);
70 /* SMP operations for this machine */
71 struct smp_ops_t *smp_ops;
73 static volatile unsigned int cpu_callin_map[NR_CPUS];
75 int smt_enabled_at_boot = 1;
77 static void (*crash_ipi_function_ptr)(struct pt_regs *) = NULL;
80 void __devinit smp_generic_kick_cpu(int nr)
82 BUG_ON(nr < 0 || nr >= NR_CPUS);
85 * The processor is currently spinning, waiting for the
86 * cpu_start field to become non-zero After we set cpu_start,
87 * the processor will continue on to secondary_start
89 paca[nr].cpu_start = 1;
94 void smp_message_recv(int msg)
97 case PPC_MSG_CALL_FUNCTION:
98 generic_smp_call_function_interrupt();
100 case PPC_MSG_RESCHEDULE:
101 /* XXX Do we have to do this? */
104 case PPC_MSG_CALL_FUNC_SINGLE:
105 generic_smp_call_function_single_interrupt();
107 case PPC_MSG_DEBUGGER_BREAK:
108 if (crash_ipi_function_ptr) {
109 crash_ipi_function_ptr(get_irq_regs());
112 #ifdef CONFIG_DEBUGGER
113 debugger_ipi(get_irq_regs());
115 #endif /* CONFIG_DEBUGGER */
118 printk("SMP %d: smp_message_recv(): unknown msg %d\n",
119 smp_processor_id(), msg);
124 void smp_send_reschedule(int cpu)
127 smp_ops->message_pass(cpu, PPC_MSG_RESCHEDULE);
130 void arch_send_call_function_single_ipi(int cpu)
132 smp_ops->message_pass(cpu, PPC_MSG_CALL_FUNC_SINGLE);
135 void arch_send_call_function_ipi(cpumask_t mask)
139 for_each_cpu_mask(cpu, mask)
140 smp_ops->message_pass(cpu, PPC_MSG_CALL_FUNCTION);
143 #ifdef CONFIG_DEBUGGER
144 void smp_send_debugger_break(int cpu)
147 smp_ops->message_pass(cpu, PPC_MSG_DEBUGGER_BREAK);
152 void crash_send_ipi(void (*crash_ipi_callback)(struct pt_regs *))
154 crash_ipi_function_ptr = crash_ipi_callback;
155 if (crash_ipi_callback && smp_ops) {
157 smp_ops->message_pass(MSG_ALL_BUT_SELF, PPC_MSG_DEBUGGER_BREAK);
162 static void stop_this_cpu(void *dummy)
169 void smp_send_stop(void)
171 smp_call_function(stop_this_cpu, NULL, 0);
174 struct thread_info *current_set[NR_CPUS];
176 static void __devinit smp_store_cpu_info(int id)
178 per_cpu(pvr, id) = mfspr(SPRN_PVR);
181 static void __init smp_create_idle(unsigned int cpu)
183 struct task_struct *p;
185 /* create a process for the processor */
188 panic("failed fork for CPU %u: %li", cpu, PTR_ERR(p));
190 paca[cpu].__current = p;
191 paca[cpu].kstack = (unsigned long) task_thread_info(p)
192 + THREAD_SIZE - STACK_FRAME_OVERHEAD;
194 current_set[cpu] = task_thread_info(p);
195 task_thread_info(p)->cpu = cpu;
198 void __init smp_prepare_cpus(unsigned int max_cpus)
202 DBG("smp_prepare_cpus\n");
205 * setup_cpu may need to be called on the boot cpu. We havent
206 * spun any cpus up but lets be paranoid.
208 BUG_ON(boot_cpuid != smp_processor_id());
211 smp_store_cpu_info(boot_cpuid);
212 cpu_callin_map[boot_cpuid] = 1;
215 max_cpus = smp_ops->probe();
219 smp_space_timers(max_cpus);
221 for_each_possible_cpu(cpu)
222 if (cpu != boot_cpuid)
223 smp_create_idle(cpu);
226 void __devinit smp_prepare_boot_cpu(void)
228 BUG_ON(smp_processor_id() != boot_cpuid);
230 cpu_set(boot_cpuid, cpu_online_map);
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))
379 /* Activate a secondary processor. */
380 int __devinit start_secondary(void *unused)
382 unsigned int cpu = smp_processor_id();
384 atomic_inc(&init_mm.mm_count);
385 current->active_mm = &init_mm;
387 smp_store_cpu_info(cpu);
388 set_dec(tb_ticks_per_jiffy);
390 cpu_callin_map[cpu] = 1;
392 smp_ops->setup_cpu(cpu);
393 if (smp_ops->take_timebase)
394 smp_ops->take_timebase();
396 if (system_state > SYSTEM_BOOTING)
399 secondary_cpu_time_init();
402 cpu_set(cpu, cpu_online_map);
411 int setup_profiling_timer(unsigned int multiplier)
416 void __init smp_cpus_done(unsigned int max_cpus)
420 /* We want the setup_cpu() here to be called from CPU 0, but our
421 * init thread may have been "borrowed" by another CPU in the meantime
422 * se we pin us down to CPU 0 for a short while
424 old_mask = current->cpus_allowed;
425 set_cpus_allowed(current, cpumask_of_cpu(boot_cpuid));
428 smp_ops->setup_cpu(boot_cpuid);
430 set_cpus_allowed(current, old_mask);
432 snapshot_timebases();
434 dump_numa_cpu_topology();
437 #ifdef CONFIG_HOTPLUG_CPU
438 int __cpu_disable(void)
440 if (smp_ops->cpu_disable)
441 return smp_ops->cpu_disable();
446 void __cpu_die(unsigned int cpu)
448 if (smp_ops->cpu_die)
449 smp_ops->cpu_die(cpu);