iwlwifi: Packing all 4965 parameters
[linux/fpc-iii.git] / arch / ia64 / kernel / smpboot.c
blob32ee5979a042c35e120ea1bc9fa0acd49bb411c8
1 /*
2 * SMP boot-related support
4 * Copyright (C) 1998-2003, 2005 Hewlett-Packard Co
5 * David Mosberger-Tang <davidm@hpl.hp.com>
6 * Copyright (C) 2001, 2004-2005 Intel Corp
7 * Rohit Seth <rohit.seth@intel.com>
8 * Suresh Siddha <suresh.b.siddha@intel.com>
9 * Gordon Jin <gordon.jin@intel.com>
10 * Ashok Raj <ashok.raj@intel.com>
12 * 01/05/16 Rohit Seth <rohit.seth@intel.com> Moved SMP booting functions from smp.c to here.
13 * 01/04/27 David Mosberger <davidm@hpl.hp.com> Added ITC synching code.
14 * 02/07/31 David Mosberger <davidm@hpl.hp.com> Switch over to hotplug-CPU boot-sequence.
15 * smp_boot_cpus()/smp_commence() is replaced by
16 * smp_prepare_cpus()/__cpu_up()/smp_cpus_done().
17 * 04/06/21 Ashok Raj <ashok.raj@intel.com> Added CPU Hotplug Support
18 * 04/12/26 Jin Gordon <gordon.jin@intel.com>
19 * 04/12/26 Rohit Seth <rohit.seth@intel.com>
20 * Add multi-threading and multi-core detection
21 * 05/01/30 Suresh Siddha <suresh.b.siddha@intel.com>
22 * Setup cpu_sibling_map and cpu_core_map
25 #include <linux/module.h>
26 #include <linux/acpi.h>
27 #include <linux/bootmem.h>
28 #include <linux/cpu.h>
29 #include <linux/delay.h>
30 #include <linux/init.h>
31 #include <linux/interrupt.h>
32 #include <linux/irq.h>
33 #include <linux/kernel.h>
34 #include <linux/kernel_stat.h>
35 #include <linux/mm.h>
36 #include <linux/notifier.h>
37 #include <linux/smp.h>
38 #include <linux/spinlock.h>
39 #include <linux/efi.h>
40 #include <linux/percpu.h>
41 #include <linux/bitops.h>
43 #include <asm/atomic.h>
44 #include <asm/cache.h>
45 #include <asm/current.h>
46 #include <asm/delay.h>
47 #include <asm/ia32.h>
48 #include <asm/io.h>
49 #include <asm/irq.h>
50 #include <asm/machvec.h>
51 #include <asm/mca.h>
52 #include <asm/page.h>
53 #include <asm/pgalloc.h>
54 #include <asm/pgtable.h>
55 #include <asm/processor.h>
56 #include <asm/ptrace.h>
57 #include <asm/sal.h>
58 #include <asm/system.h>
59 #include <asm/tlbflush.h>
60 #include <asm/unistd.h>
61 #include <asm/sn/arch.h>
63 #define SMP_DEBUG 0
65 #if SMP_DEBUG
66 #define Dprintk(x...) printk(x)
67 #else
68 #define Dprintk(x...)
69 #endif
71 #ifdef CONFIG_HOTPLUG_CPU
72 #ifdef CONFIG_PERMIT_BSP_REMOVE
73 #define bsp_remove_ok 1
74 #else
75 #define bsp_remove_ok 0
76 #endif
79 * Store all idle threads, this can be reused instead of creating
80 * a new thread. Also avoids complicated thread destroy functionality
81 * for idle threads.
83 struct task_struct *idle_thread_array[NR_CPUS];
86 * Global array allocated for NR_CPUS at boot time
88 struct sal_to_os_boot sal_boot_rendez_state[NR_CPUS];
91 * start_ap in head.S uses this to store current booting cpu
92 * info.
94 struct sal_to_os_boot *sal_state_for_booting_cpu = &sal_boot_rendez_state[0];
96 #define set_brendez_area(x) (sal_state_for_booting_cpu = &sal_boot_rendez_state[(x)]);
98 #define get_idle_for_cpu(x) (idle_thread_array[(x)])
99 #define set_idle_for_cpu(x,p) (idle_thread_array[(x)] = (p))
101 #else
103 #define get_idle_for_cpu(x) (NULL)
104 #define set_idle_for_cpu(x,p)
105 #define set_brendez_area(x)
106 #endif
110 * ITC synchronization related stuff:
112 #define MASTER (0)
113 #define SLAVE (SMP_CACHE_BYTES/8)
115 #define NUM_ROUNDS 64 /* magic value */
116 #define NUM_ITERS 5 /* likewise */
118 static DEFINE_SPINLOCK(itc_sync_lock);
119 static volatile unsigned long go[SLAVE + 1];
121 #define DEBUG_ITC_SYNC 0
123 extern void start_ap (void);
124 extern unsigned long ia64_iobase;
126 struct task_struct *task_for_booting_cpu;
129 * State for each CPU
131 DEFINE_PER_CPU(int, cpu_state);
133 /* Bitmasks of currently online, and possible CPUs */
134 cpumask_t cpu_online_map;
135 EXPORT_SYMBOL(cpu_online_map);
136 cpumask_t cpu_possible_map = CPU_MASK_NONE;
137 EXPORT_SYMBOL(cpu_possible_map);
139 cpumask_t cpu_core_map[NR_CPUS] __cacheline_aligned;
140 DEFINE_PER_CPU_SHARED_ALIGNED(cpumask_t, cpu_sibling_map);
141 EXPORT_PER_CPU_SYMBOL(cpu_sibling_map);
143 int smp_num_siblings = 1;
145 /* which logical CPU number maps to which CPU (physical APIC ID) */
146 volatile int ia64_cpu_to_sapicid[NR_CPUS];
147 EXPORT_SYMBOL(ia64_cpu_to_sapicid);
149 static volatile cpumask_t cpu_callin_map;
151 struct smp_boot_data smp_boot_data __initdata;
153 unsigned long ap_wakeup_vector = -1; /* External Int use to wakeup APs */
155 char __initdata no_int_routing;
157 unsigned char smp_int_redirect; /* are INT and IPI redirectable by the chipset? */
159 #ifdef CONFIG_FORCE_CPEI_RETARGET
160 #define CPEI_OVERRIDE_DEFAULT (1)
161 #else
162 #define CPEI_OVERRIDE_DEFAULT (0)
163 #endif
165 unsigned int force_cpei_retarget = CPEI_OVERRIDE_DEFAULT;
167 static int __init
168 cmdl_force_cpei(char *str)
170 int value=0;
172 get_option (&str, &value);
173 force_cpei_retarget = value;
175 return 1;
178 __setup("force_cpei=", cmdl_force_cpei);
180 static int __init
181 nointroute (char *str)
183 no_int_routing = 1;
184 printk ("no_int_routing on\n");
185 return 1;
188 __setup("nointroute", nointroute);
190 static void fix_b0_for_bsp(void)
192 #ifdef CONFIG_HOTPLUG_CPU
193 int cpuid;
194 static int fix_bsp_b0 = 1;
196 cpuid = smp_processor_id();
199 * Cache the b0 value on the first AP that comes up
201 if (!(fix_bsp_b0 && cpuid))
202 return;
204 sal_boot_rendez_state[0].br[0] = sal_boot_rendez_state[cpuid].br[0];
205 printk ("Fixed BSP b0 value from CPU %d\n", cpuid);
207 fix_bsp_b0 = 0;
208 #endif
211 void
212 sync_master (void *arg)
214 unsigned long flags, i;
216 go[MASTER] = 0;
218 local_irq_save(flags);
220 for (i = 0; i < NUM_ROUNDS*NUM_ITERS; ++i) {
221 while (!go[MASTER])
222 cpu_relax();
223 go[MASTER] = 0;
224 go[SLAVE] = ia64_get_itc();
227 local_irq_restore(flags);
231 * Return the number of cycles by which our itc differs from the itc on the master
232 * (time-keeper) CPU. A positive number indicates our itc is ahead of the master,
233 * negative that it is behind.
235 static inline long
236 get_delta (long *rt, long *master)
238 unsigned long best_t0 = 0, best_t1 = ~0UL, best_tm = 0;
239 unsigned long tcenter, t0, t1, tm;
240 long i;
242 for (i = 0; i < NUM_ITERS; ++i) {
243 t0 = ia64_get_itc();
244 go[MASTER] = 1;
245 while (!(tm = go[SLAVE]))
246 cpu_relax();
247 go[SLAVE] = 0;
248 t1 = ia64_get_itc();
250 if (t1 - t0 < best_t1 - best_t0)
251 best_t0 = t0, best_t1 = t1, best_tm = tm;
254 *rt = best_t1 - best_t0;
255 *master = best_tm - best_t0;
257 /* average best_t0 and best_t1 without overflow: */
258 tcenter = (best_t0/2 + best_t1/2);
259 if (best_t0 % 2 + best_t1 % 2 == 2)
260 ++tcenter;
261 return tcenter - best_tm;
265 * Synchronize ar.itc of the current (slave) CPU with the ar.itc of the MASTER CPU
266 * (normally the time-keeper CPU). We use a closed loop to eliminate the possibility of
267 * unaccounted-for errors (such as getting a machine check in the middle of a calibration
268 * step). The basic idea is for the slave to ask the master what itc value it has and to
269 * read its own itc before and after the master responds. Each iteration gives us three
270 * timestamps:
272 * slave master
274 * t0 ---\
275 * ---\
276 * --->
277 * tm
278 * /---
279 * /---
280 * t1 <---
283 * The goal is to adjust the slave's ar.itc such that tm falls exactly half-way between t0
284 * and t1. If we achieve this, the clocks are synchronized provided the interconnect
285 * between the slave and the master is symmetric. Even if the interconnect were
286 * asymmetric, we would still know that the synchronization error is smaller than the
287 * roundtrip latency (t0 - t1).
289 * When the interconnect is quiet and symmetric, this lets us synchronize the itc to
290 * within one or two cycles. However, we can only *guarantee* that the synchronization is
291 * accurate to within a round-trip time, which is typically in the range of several
292 * hundred cycles (e.g., ~500 cycles). In practice, this means that the itc's are usually
293 * almost perfectly synchronized, but we shouldn't assume that the accuracy is much better
294 * than half a micro second or so.
296 void
297 ia64_sync_itc (unsigned int master)
299 long i, delta, adj, adjust_latency = 0, done = 0;
300 unsigned long flags, rt, master_time_stamp, bound;
301 #if DEBUG_ITC_SYNC
302 struct {
303 long rt; /* roundtrip time */
304 long master; /* master's timestamp */
305 long diff; /* difference between midpoint and master's timestamp */
306 long lat; /* estimate of itc adjustment latency */
307 } t[NUM_ROUNDS];
308 #endif
311 * Make sure local timer ticks are disabled while we sync. If
312 * they were enabled, we'd have to worry about nasty issues
313 * like setting the ITC ahead of (or a long time before) the
314 * next scheduled tick.
316 BUG_ON((ia64_get_itv() & (1 << 16)) == 0);
318 go[MASTER] = 1;
320 if (smp_call_function_single(master, sync_master, NULL, 1, 0) < 0) {
321 printk(KERN_ERR "sync_itc: failed to get attention of CPU %u!\n", master);
322 return;
325 while (go[MASTER])
326 cpu_relax(); /* wait for master to be ready */
328 spin_lock_irqsave(&itc_sync_lock, flags);
330 for (i = 0; i < NUM_ROUNDS; ++i) {
331 delta = get_delta(&rt, &master_time_stamp);
332 if (delta == 0) {
333 done = 1; /* let's lock on to this... */
334 bound = rt;
337 if (!done) {
338 if (i > 0) {
339 adjust_latency += -delta;
340 adj = -delta + adjust_latency/4;
341 } else
342 adj = -delta;
344 ia64_set_itc(ia64_get_itc() + adj);
346 #if DEBUG_ITC_SYNC
347 t[i].rt = rt;
348 t[i].master = master_time_stamp;
349 t[i].diff = delta;
350 t[i].lat = adjust_latency/4;
351 #endif
354 spin_unlock_irqrestore(&itc_sync_lock, flags);
356 #if DEBUG_ITC_SYNC
357 for (i = 0; i < NUM_ROUNDS; ++i)
358 printk("rt=%5ld master=%5ld diff=%5ld adjlat=%5ld\n",
359 t[i].rt, t[i].master, t[i].diff, t[i].lat);
360 #endif
362 printk(KERN_INFO "CPU %d: synchronized ITC with CPU %u (last diff %ld cycles, "
363 "maxerr %lu cycles)\n", smp_processor_id(), master, delta, rt);
367 * Ideally sets up per-cpu profiling hooks. Doesn't do much now...
369 static inline void __devinit
370 smp_setup_percpu_timer (void)
374 static void __cpuinit
375 smp_callin (void)
377 int cpuid, phys_id, itc_master;
378 struct cpuinfo_ia64 *last_cpuinfo, *this_cpuinfo;
379 extern void ia64_init_itm(void);
380 extern volatile int time_keeper_id;
382 #ifdef CONFIG_PERFMON
383 extern void pfm_init_percpu(void);
384 #endif
386 cpuid = smp_processor_id();
387 phys_id = hard_smp_processor_id();
388 itc_master = time_keeper_id;
390 if (cpu_online(cpuid)) {
391 printk(KERN_ERR "huh, phys CPU#0x%x, CPU#0x%x already present??\n",
392 phys_id, cpuid);
393 BUG();
396 fix_b0_for_bsp();
398 lock_ipi_calllock();
399 spin_lock(&vector_lock);
400 /* Setup the per cpu irq handling data structures */
401 __setup_vector_irq(cpuid);
402 cpu_set(cpuid, cpu_online_map);
403 unlock_ipi_calllock();
404 per_cpu(cpu_state, cpuid) = CPU_ONLINE;
405 spin_unlock(&vector_lock);
407 smp_setup_percpu_timer();
409 ia64_mca_cmc_vector_setup(); /* Setup vector on AP */
411 #ifdef CONFIG_PERFMON
412 pfm_init_percpu();
413 #endif
415 local_irq_enable();
417 if (!(sal_platform_features & IA64_SAL_PLATFORM_FEATURE_ITC_DRIFT)) {
419 * Synchronize the ITC with the BP. Need to do this after irqs are
420 * enabled because ia64_sync_itc() calls smp_call_function_single(), which
421 * calls spin_unlock_bh(), which calls spin_unlock_bh(), which calls
422 * local_bh_enable(), which bugs out if irqs are not enabled...
424 Dprintk("Going to syncup ITC with ITC Master.\n");
425 ia64_sync_itc(itc_master);
429 * Get our bogomips.
431 ia64_init_itm();
434 * Delay calibration can be skipped if new processor is identical to the
435 * previous processor.
437 last_cpuinfo = cpu_data(cpuid - 1);
438 this_cpuinfo = local_cpu_data;
439 if (last_cpuinfo->itc_freq != this_cpuinfo->itc_freq ||
440 last_cpuinfo->proc_freq != this_cpuinfo->proc_freq ||
441 last_cpuinfo->features != this_cpuinfo->features ||
442 last_cpuinfo->revision != this_cpuinfo->revision ||
443 last_cpuinfo->family != this_cpuinfo->family ||
444 last_cpuinfo->archrev != this_cpuinfo->archrev ||
445 last_cpuinfo->model != this_cpuinfo->model)
446 calibrate_delay();
447 local_cpu_data->loops_per_jiffy = loops_per_jiffy;
449 #ifdef CONFIG_IA32_SUPPORT
450 ia32_gdt_init();
451 #endif
454 * Allow the master to continue.
456 cpu_set(cpuid, cpu_callin_map);
457 Dprintk("Stack on CPU %d at about %p\n",cpuid, &cpuid);
462 * Activate a secondary processor. head.S calls this.
464 int __cpuinit
465 start_secondary (void *unused)
467 /* Early console may use I/O ports */
468 ia64_set_kr(IA64_KR_IO_BASE, __pa(ia64_iobase));
469 Dprintk("start_secondary: starting CPU 0x%x\n", hard_smp_processor_id());
470 efi_map_pal_code();
471 cpu_init();
472 preempt_disable();
473 smp_callin();
475 cpu_idle();
476 return 0;
479 struct pt_regs * __cpuinit idle_regs(struct pt_regs *regs)
481 return NULL;
484 struct create_idle {
485 struct work_struct work;
486 struct task_struct *idle;
487 struct completion done;
488 int cpu;
491 void __cpuinit
492 do_fork_idle(struct work_struct *work)
494 struct create_idle *c_idle =
495 container_of(work, struct create_idle, work);
497 c_idle->idle = fork_idle(c_idle->cpu);
498 complete(&c_idle->done);
501 static int __cpuinit
502 do_boot_cpu (int sapicid, int cpu)
504 int timeout;
505 struct create_idle c_idle = {
506 .work = __WORK_INITIALIZER(c_idle.work, do_fork_idle),
507 .cpu = cpu,
508 .done = COMPLETION_INITIALIZER(c_idle.done),
511 c_idle.idle = get_idle_for_cpu(cpu);
512 if (c_idle.idle) {
513 init_idle(c_idle.idle, cpu);
514 goto do_rest;
518 * We can't use kernel_thread since we must avoid to reschedule the child.
520 if (!keventd_up() || current_is_keventd())
521 c_idle.work.func(&c_idle.work);
522 else {
523 schedule_work(&c_idle.work);
524 wait_for_completion(&c_idle.done);
527 if (IS_ERR(c_idle.idle))
528 panic("failed fork for CPU %d", cpu);
530 set_idle_for_cpu(cpu, c_idle.idle);
532 do_rest:
533 task_for_booting_cpu = c_idle.idle;
535 Dprintk("Sending wakeup vector %lu to AP 0x%x/0x%x.\n", ap_wakeup_vector, cpu, sapicid);
537 set_brendez_area(cpu);
538 platform_send_ipi(cpu, ap_wakeup_vector, IA64_IPI_DM_INT, 0);
541 * Wait 10s total for the AP to start
543 Dprintk("Waiting on callin_map ...");
544 for (timeout = 0; timeout < 100000; timeout++) {
545 if (cpu_isset(cpu, cpu_callin_map))
546 break; /* It has booted */
547 udelay(100);
549 Dprintk("\n");
551 if (!cpu_isset(cpu, cpu_callin_map)) {
552 printk(KERN_ERR "Processor 0x%x/0x%x is stuck.\n", cpu, sapicid);
553 ia64_cpu_to_sapicid[cpu] = -1;
554 cpu_clear(cpu, cpu_online_map); /* was set in smp_callin() */
555 return -EINVAL;
557 return 0;
560 static int __init
561 decay (char *str)
563 int ticks;
564 get_option (&str, &ticks);
565 return 1;
568 __setup("decay=", decay);
571 * Initialize the logical CPU number to SAPICID mapping
573 void __init
574 smp_build_cpu_map (void)
576 int sapicid, cpu, i;
577 int boot_cpu_id = hard_smp_processor_id();
579 for (cpu = 0; cpu < NR_CPUS; cpu++) {
580 ia64_cpu_to_sapicid[cpu] = -1;
583 ia64_cpu_to_sapicid[0] = boot_cpu_id;
584 cpus_clear(cpu_present_map);
585 cpu_set(0, cpu_present_map);
586 cpu_set(0, cpu_possible_map);
587 for (cpu = 1, i = 0; i < smp_boot_data.cpu_count; i++) {
588 sapicid = smp_boot_data.cpu_phys_id[i];
589 if (sapicid == boot_cpu_id)
590 continue;
591 cpu_set(cpu, cpu_present_map);
592 cpu_set(cpu, cpu_possible_map);
593 ia64_cpu_to_sapicid[cpu] = sapicid;
594 cpu++;
599 * Cycle through the APs sending Wakeup IPIs to boot each.
601 void __init
602 smp_prepare_cpus (unsigned int max_cpus)
604 int boot_cpu_id = hard_smp_processor_id();
607 * Initialize the per-CPU profiling counter/multiplier
610 smp_setup_percpu_timer();
613 * We have the boot CPU online for sure.
615 cpu_set(0, cpu_online_map);
616 cpu_set(0, cpu_callin_map);
618 local_cpu_data->loops_per_jiffy = loops_per_jiffy;
619 ia64_cpu_to_sapicid[0] = boot_cpu_id;
621 printk(KERN_INFO "Boot processor id 0x%x/0x%x\n", 0, boot_cpu_id);
623 current_thread_info()->cpu = 0;
626 * If SMP should be disabled, then really disable it!
628 if (!max_cpus) {
629 printk(KERN_INFO "SMP mode deactivated.\n");
630 cpus_clear(cpu_online_map);
631 cpus_clear(cpu_present_map);
632 cpus_clear(cpu_possible_map);
633 cpu_set(0, cpu_online_map);
634 cpu_set(0, cpu_present_map);
635 cpu_set(0, cpu_possible_map);
636 return;
640 void __devinit smp_prepare_boot_cpu(void)
642 cpu_set(smp_processor_id(), cpu_online_map);
643 cpu_set(smp_processor_id(), cpu_callin_map);
644 per_cpu(cpu_state, smp_processor_id()) = CPU_ONLINE;
647 #ifdef CONFIG_HOTPLUG_CPU
648 static inline void
649 clear_cpu_sibling_map(int cpu)
651 int i;
653 for_each_cpu_mask(i, per_cpu(cpu_sibling_map, cpu))
654 cpu_clear(cpu, per_cpu(cpu_sibling_map, i));
655 for_each_cpu_mask(i, cpu_core_map[cpu])
656 cpu_clear(cpu, cpu_core_map[i]);
658 per_cpu(cpu_sibling_map, cpu) = cpu_core_map[cpu] = CPU_MASK_NONE;
661 static void
662 remove_siblinginfo(int cpu)
664 int last = 0;
666 if (cpu_data(cpu)->threads_per_core == 1 &&
667 cpu_data(cpu)->cores_per_socket == 1) {
668 cpu_clear(cpu, cpu_core_map[cpu]);
669 cpu_clear(cpu, per_cpu(cpu_sibling_map, cpu));
670 return;
673 last = (cpus_weight(cpu_core_map[cpu]) == 1 ? 1 : 0);
675 /* remove it from all sibling map's */
676 clear_cpu_sibling_map(cpu);
679 extern void fixup_irqs(void);
681 int migrate_platform_irqs(unsigned int cpu)
683 int new_cpei_cpu;
684 irq_desc_t *desc = NULL;
685 cpumask_t mask;
686 int retval = 0;
689 * dont permit CPEI target to removed.
691 if (cpe_vector > 0 && is_cpu_cpei_target(cpu)) {
692 printk ("CPU (%d) is CPEI Target\n", cpu);
693 if (can_cpei_retarget()) {
695 * Now re-target the CPEI to a different processor
697 new_cpei_cpu = any_online_cpu(cpu_online_map);
698 mask = cpumask_of_cpu(new_cpei_cpu);
699 set_cpei_target_cpu(new_cpei_cpu);
700 desc = irq_desc + ia64_cpe_irq;
702 * Switch for now, immediately, we need to do fake intr
703 * as other interrupts, but need to study CPEI behaviour with
704 * polling before making changes.
706 if (desc) {
707 desc->chip->disable(ia64_cpe_irq);
708 desc->chip->set_affinity(ia64_cpe_irq, mask);
709 desc->chip->enable(ia64_cpe_irq);
710 printk ("Re-targetting CPEI to cpu %d\n", new_cpei_cpu);
713 if (!desc) {
714 printk ("Unable to retarget CPEI, offline cpu [%d] failed\n", cpu);
715 retval = -EBUSY;
718 return retval;
721 /* must be called with cpucontrol mutex held */
722 int __cpu_disable(void)
724 int cpu = smp_processor_id();
727 * dont permit boot processor for now
729 if (cpu == 0 && !bsp_remove_ok) {
730 printk ("Your platform does not support removal of BSP\n");
731 return (-EBUSY);
734 if (ia64_platform_is("sn2")) {
735 if (!sn_cpu_disable_allowed(cpu))
736 return -EBUSY;
739 cpu_clear(cpu, cpu_online_map);
741 if (migrate_platform_irqs(cpu)) {
742 cpu_set(cpu, cpu_online_map);
743 return (-EBUSY);
746 remove_siblinginfo(cpu);
747 cpu_clear(cpu, cpu_online_map);
748 fixup_irqs();
749 local_flush_tlb_all();
750 cpu_clear(cpu, cpu_callin_map);
751 return 0;
754 void __cpu_die(unsigned int cpu)
756 unsigned int i;
758 for (i = 0; i < 100; i++) {
759 /* They ack this in play_dead by setting CPU_DEAD */
760 if (per_cpu(cpu_state, cpu) == CPU_DEAD)
762 printk ("CPU %d is now offline\n", cpu);
763 return;
765 msleep(100);
767 printk(KERN_ERR "CPU %u didn't die...\n", cpu);
769 #endif /* CONFIG_HOTPLUG_CPU */
771 void
772 smp_cpus_done (unsigned int dummy)
774 int cpu;
775 unsigned long bogosum = 0;
778 * Allow the user to impress friends.
781 for_each_online_cpu(cpu) {
782 bogosum += cpu_data(cpu)->loops_per_jiffy;
785 printk(KERN_INFO "Total of %d processors activated (%lu.%02lu BogoMIPS).\n",
786 (int)num_online_cpus(), bogosum/(500000/HZ), (bogosum/(5000/HZ))%100);
789 static inline void __devinit
790 set_cpu_sibling_map(int cpu)
792 int i;
794 for_each_online_cpu(i) {
795 if ((cpu_data(cpu)->socket_id == cpu_data(i)->socket_id)) {
796 cpu_set(i, cpu_core_map[cpu]);
797 cpu_set(cpu, cpu_core_map[i]);
798 if (cpu_data(cpu)->core_id == cpu_data(i)->core_id) {
799 cpu_set(i, per_cpu(cpu_sibling_map, cpu));
800 cpu_set(cpu, per_cpu(cpu_sibling_map, i));
806 int __cpuinit
807 __cpu_up (unsigned int cpu)
809 int ret;
810 int sapicid;
812 sapicid = ia64_cpu_to_sapicid[cpu];
813 if (sapicid == -1)
814 return -EINVAL;
817 * Already booted cpu? not valid anymore since we dont
818 * do idle loop tightspin anymore.
820 if (cpu_isset(cpu, cpu_callin_map))
821 return -EINVAL;
823 per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
824 /* Processor goes to start_secondary(), sets online flag */
825 ret = do_boot_cpu(sapicid, cpu);
826 if (ret < 0)
827 return ret;
829 if (cpu_data(cpu)->threads_per_core == 1 &&
830 cpu_data(cpu)->cores_per_socket == 1) {
831 cpu_set(cpu, per_cpu(cpu_sibling_map, cpu));
832 cpu_set(cpu, cpu_core_map[cpu]);
833 return 0;
836 set_cpu_sibling_map(cpu);
838 return 0;
842 * Assume that CPUs have been discovered by some platform-dependent interface. For
843 * SoftSDV/Lion, that would be ACPI.
845 * Setup of the IPI irq handler is done in irq.c:init_IRQ_SMP().
847 void __init
848 init_smp_config(void)
850 struct fptr {
851 unsigned long fp;
852 unsigned long gp;
853 } *ap_startup;
854 long sal_ret;
856 /* Tell SAL where to drop the APs. */
857 ap_startup = (struct fptr *) start_ap;
858 sal_ret = ia64_sal_set_vectors(SAL_VECTOR_OS_BOOT_RENDEZ,
859 ia64_tpa(ap_startup->fp), ia64_tpa(ap_startup->gp), 0, 0, 0, 0);
860 if (sal_ret < 0)
861 printk(KERN_ERR "SMP: Can't set SAL AP Boot Rendezvous: %s\n",
862 ia64_sal_strerror(sal_ret));
866 * identify_siblings(cpu) gets called from identify_cpu. This populates the
867 * information related to logical execution units in per_cpu_data structure.
869 void __devinit
870 identify_siblings(struct cpuinfo_ia64 *c)
872 s64 status;
873 u16 pltid;
874 pal_logical_to_physical_t info;
876 if ((status = ia64_pal_logical_to_phys(-1, &info)) != PAL_STATUS_SUCCESS) {
877 if (status != PAL_STATUS_UNIMPLEMENTED) {
878 printk(KERN_ERR
879 "ia64_pal_logical_to_phys failed with %ld\n",
880 status);
881 return;
884 info.overview_ppid = 0;
885 info.overview_cpp = 1;
886 info.overview_tpc = 1;
888 if ((status = ia64_sal_physical_id_info(&pltid)) != PAL_STATUS_SUCCESS) {
889 printk(KERN_ERR "ia64_sal_pltid failed with %ld\n", status);
890 return;
893 c->socket_id = (pltid << 8) | info.overview_ppid;
895 if (info.overview_cpp == 1 && info.overview_tpc == 1)
896 return;
898 c->cores_per_socket = info.overview_cpp;
899 c->threads_per_core = info.overview_tpc;
900 c->num_log = info.overview_num_log;
902 c->core_id = info.log1_cid;
903 c->thread_id = info.log1_tid;
907 * returns non zero, if multi-threading is enabled
908 * on at least one physical package. Due to hotplug cpu
909 * and (maxcpus=), all threads may not necessarily be enabled
910 * even though the processor supports multi-threading.
912 int is_multithreading_enabled(void)
914 int i, j;
916 for_each_present_cpu(i) {
917 for_each_present_cpu(j) {
918 if (j == i)
919 continue;
920 if ((cpu_data(j)->socket_id == cpu_data(i)->socket_id)) {
921 if (cpu_data(j)->core_id == cpu_data(i)->core_id)
922 return 1;
926 return 0;
928 EXPORT_SYMBOL_GPL(is_multithreading_enabled);