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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * SMP boot-related support
4 *
5 * Copyright (C) 1998-2003, 2005 Hewlett-Packard Co
6 * David Mosberger-Tang <davidm@hpl.hp.com>
7 * Copyright (C) 2001, 2004-2005 Intel Corp
8 * Rohit Seth <rohit.seth@intel.com>
9 * Suresh Siddha <suresh.b.siddha@intel.com>
10 * Gordon Jin <gordon.jin@intel.com>
11 * Ashok Raj <ashok.raj@intel.com>
12 *
13 * 01/05/16 Rohit Seth <rohit.seth@intel.com> Moved SMP booting functions from smp.c to here.
14 * 01/04/27 David Mosberger <davidm@hpl.hp.com> Added ITC synching code.
15 * 02/07/31 David Mosberger <davidm@hpl.hp.com> Switch over to hotplug-CPU boot-sequence.
16 * smp_boot_cpus()/smp_commence() is replaced by
17 * smp_prepare_cpus()/__cpu_up()/smp_cpus_done().
18 * 04/06/21 Ashok Raj <ashok.raj@intel.com> Added CPU Hotplug Support
19 * 04/12/26 Jin Gordon <gordon.jin@intel.com>
20 * 04/12/26 Rohit Seth <rohit.seth@intel.com>
21 * Add multi-threading and multi-core detection
22 * 05/01/30 Suresh Siddha <suresh.b.siddha@intel.com>
23 * Setup cpu_sibling_map and cpu_core_map
24 */
25
26#include <linux/module.h>
27#include <linux/acpi.h>
28#include <linux/memblock.h>
29#include <linux/cpu.h>
30#include <linux/delay.h>
31#include <linux/init.h>
32#include <linux/interrupt.h>
33#include <linux/irq.h>
34#include <linux/kernel.h>
35#include <linux/kernel_stat.h>
36#include <linux/mm.h>
37#include <linux/notifier.h>
38#include <linux/smp.h>
39#include <linux/spinlock.h>
40#include <linux/efi.h>
41#include <linux/percpu.h>
42#include <linux/bitops.h>
43
44#include <linux/atomic.h>
45#include <asm/cache.h>
46#include <asm/current.h>
47#include <asm/delay.h>
48#include <asm/io.h>
49#include <asm/irq.h>
50#include <asm/mca.h>
51#include <asm/page.h>
52#include <asm/pgalloc.h>
53#include <asm/pgtable.h>
54#include <asm/processor.h>
55#include <asm/ptrace.h>
56#include <asm/sal.h>
57#include <asm/tlbflush.h>
58#include <asm/unistd.h>
59
60#define SMP_DEBUG 0
61
62#if SMP_DEBUG
63#define Dprintk(x...) printk(x)
64#else
65#define Dprintk(x...)
66#endif
67
68#ifdef CONFIG_HOTPLUG_CPU
69#ifdef CONFIG_PERMIT_BSP_REMOVE
70#define bsp_remove_ok 1
71#else
72#define bsp_remove_ok 0
73#endif
74
75/*
76 * Global array allocated for NR_CPUS at boot time
77 */
78struct sal_to_os_boot sal_boot_rendez_state[NR_CPUS];
79
80/*
81 * start_ap in head.S uses this to store current booting cpu
82 * info.
83 */
84struct sal_to_os_boot *sal_state_for_booting_cpu = &sal_boot_rendez_state[0];
85
86#define set_brendez_area(x) (sal_state_for_booting_cpu = &sal_boot_rendez_state[(x)]);
87
88#else
89#define set_brendez_area(x)
90#endif
91
92
93/*
94 * ITC synchronization related stuff:
95 */
96#define MASTER (0)
97#define SLAVE (SMP_CACHE_BYTES/8)
98
99#define NUM_ROUNDS 64 /* magic value */
100#define NUM_ITERS 5 /* likewise */
101
102static DEFINE_SPINLOCK(itc_sync_lock);
103static volatile unsigned long go[SLAVE + 1];
104
105#define DEBUG_ITC_SYNC 0
106
107extern void start_ap (void);
108extern unsigned long ia64_iobase;
109
110struct task_struct *task_for_booting_cpu;
111
112/*
113 * State for each CPU
114 */
115DEFINE_PER_CPU(int, cpu_state);
116
117cpumask_t cpu_core_map[NR_CPUS] __cacheline_aligned;
118EXPORT_SYMBOL(cpu_core_map);
119DEFINE_PER_CPU_SHARED_ALIGNED(cpumask_t, cpu_sibling_map);
120EXPORT_PER_CPU_SYMBOL(cpu_sibling_map);
121
122int smp_num_siblings = 1;
123
124/* which logical CPU number maps to which CPU (physical APIC ID) */
125volatile int ia64_cpu_to_sapicid[NR_CPUS];
126EXPORT_SYMBOL(ia64_cpu_to_sapicid);
127
128static cpumask_t cpu_callin_map;
129
130struct smp_boot_data smp_boot_data __initdata;
131
132unsigned long ap_wakeup_vector = -1; /* External Int use to wakeup APs */
133
134char __initdata no_int_routing;
135
136unsigned char smp_int_redirect; /* are INT and IPI redirectable by the chipset? */
137
138#ifdef CONFIG_FORCE_CPEI_RETARGET
139#define CPEI_OVERRIDE_DEFAULT (1)
140#else
141#define CPEI_OVERRIDE_DEFAULT (0)
142#endif
143
144unsigned int force_cpei_retarget = CPEI_OVERRIDE_DEFAULT;
145
146static int __init
147cmdl_force_cpei(char *str)
148{
149 int value=0;
150
151 get_option (&str, &value);
152 force_cpei_retarget = value;
153
154 return 1;
155}
156
157__setup("force_cpei=", cmdl_force_cpei);
158
159static int __init
160nointroute (char *str)
161{
162 no_int_routing = 1;
163 printk ("no_int_routing on\n");
164 return 1;
165}
166
167__setup("nointroute", nointroute);
168
169static void fix_b0_for_bsp(void)
170{
171#ifdef CONFIG_HOTPLUG_CPU
172 int cpuid;
173 static int fix_bsp_b0 = 1;
174
175 cpuid = smp_processor_id();
176
177 /*
178 * Cache the b0 value on the first AP that comes up
179 */
180 if (!(fix_bsp_b0 && cpuid))
181 return;
182
183 sal_boot_rendez_state[0].br[0] = sal_boot_rendez_state[cpuid].br[0];
184 printk ("Fixed BSP b0 value from CPU %d\n", cpuid);
185
186 fix_bsp_b0 = 0;
187#endif
188}
189
190void
191sync_master (void *arg)
192{
193 unsigned long flags, i;
194
195 go[MASTER] = 0;
196
197 local_irq_save(flags);
198 {
199 for (i = 0; i < NUM_ROUNDS*NUM_ITERS; ++i) {
200 while (!go[MASTER])
201 cpu_relax();
202 go[MASTER] = 0;
203 go[SLAVE] = ia64_get_itc();
204 }
205 }
206 local_irq_restore(flags);
207}
208
209/*
210 * Return the number of cycles by which our itc differs from the itc on the master
211 * (time-keeper) CPU. A positive number indicates our itc is ahead of the master,
212 * negative that it is behind.
213 */
214static inline long
215get_delta (long *rt, long *master)
216{
217 unsigned long best_t0 = 0, best_t1 = ~0UL, best_tm = 0;
218 unsigned long tcenter, t0, t1, tm;
219 long i;
220
221 for (i = 0; i < NUM_ITERS; ++i) {
222 t0 = ia64_get_itc();
223 go[MASTER] = 1;
224 while (!(tm = go[SLAVE]))
225 cpu_relax();
226 go[SLAVE] = 0;
227 t1 = ia64_get_itc();
228
229 if (t1 - t0 < best_t1 - best_t0)
230 best_t0 = t0, best_t1 = t1, best_tm = tm;
231 }
232
233 *rt = best_t1 - best_t0;
234 *master = best_tm - best_t0;
235
236 /* average best_t0 and best_t1 without overflow: */
237 tcenter = (best_t0/2 + best_t1/2);
238 if (best_t0 % 2 + best_t1 % 2 == 2)
239 ++tcenter;
240 return tcenter - best_tm;
241}
242
243/*
244 * Synchronize ar.itc of the current (slave) CPU with the ar.itc of the MASTER CPU
245 * (normally the time-keeper CPU). We use a closed loop to eliminate the possibility of
246 * unaccounted-for errors (such as getting a machine check in the middle of a calibration
247 * step). The basic idea is for the slave to ask the master what itc value it has and to
248 * read its own itc before and after the master responds. Each iteration gives us three
249 * timestamps:
250 *
251 * slave master
252 *
253 * t0 ---\
254 * ---\
255 * --->
256 * tm
257 * /---
258 * /---
259 * t1 <---
260 *
261 *
262 * The goal is to adjust the slave's ar.itc such that tm falls exactly half-way between t0
263 * and t1. If we achieve this, the clocks are synchronized provided the interconnect
264 * between the slave and the master is symmetric. Even if the interconnect were
265 * asymmetric, we would still know that the synchronization error is smaller than the
266 * roundtrip latency (t0 - t1).
267 *
268 * When the interconnect is quiet and symmetric, this lets us synchronize the itc to
269 * within one or two cycles. However, we can only *guarantee* that the synchronization is
270 * accurate to within a round-trip time, which is typically in the range of several
271 * hundred cycles (e.g., ~500 cycles). In practice, this means that the itc's are usually
272 * almost perfectly synchronized, but we shouldn't assume that the accuracy is much better
273 * than half a micro second or so.
274 */
275void
276ia64_sync_itc (unsigned int master)
277{
278 long i, delta, adj, adjust_latency = 0, done = 0;
279 unsigned long flags, rt, master_time_stamp, bound;
280#if DEBUG_ITC_SYNC
281 struct {
282 long rt; /* roundtrip time */
283 long master; /* master's timestamp */
284 long diff; /* difference between midpoint and master's timestamp */
285 long lat; /* estimate of itc adjustment latency */
286 } t[NUM_ROUNDS];
287#endif
288
289 /*
290 * Make sure local timer ticks are disabled while we sync. If
291 * they were enabled, we'd have to worry about nasty issues
292 * like setting the ITC ahead of (or a long time before) the
293 * next scheduled tick.
294 */
295 BUG_ON((ia64_get_itv() & (1 << 16)) == 0);
296
297 go[MASTER] = 1;
298
299 if (smp_call_function_single(master, sync_master, NULL, 0) < 0) {
300 printk(KERN_ERR "sync_itc: failed to get attention of CPU %u!\n", master);
301 return;
302 }
303
304 while (go[MASTER])
305 cpu_relax(); /* wait for master to be ready */
306
307 spin_lock_irqsave(&itc_sync_lock, flags);
308 {
309 for (i = 0; i < NUM_ROUNDS; ++i) {
310 delta = get_delta(&rt, &master_time_stamp);
311 if (delta == 0) {
312 done = 1; /* let's lock on to this... */
313 bound = rt;
314 }
315
316 if (!done) {
317 if (i > 0) {
318 adjust_latency += -delta;
319 adj = -delta + adjust_latency/4;
320 } else
321 adj = -delta;
322
323 ia64_set_itc(ia64_get_itc() + adj);
324 }
325#if DEBUG_ITC_SYNC
326 t[i].rt = rt;
327 t[i].master = master_time_stamp;
328 t[i].diff = delta;
329 t[i].lat = adjust_latency/4;
330#endif
331 }
332 }
333 spin_unlock_irqrestore(&itc_sync_lock, flags);
334
335#if DEBUG_ITC_SYNC
336 for (i = 0; i < NUM_ROUNDS; ++i)
337 printk("rt=%5ld master=%5ld diff=%5ld adjlat=%5ld\n",
338 t[i].rt, t[i].master, t[i].diff, t[i].lat);
339#endif
340
341 printk(KERN_INFO "CPU %d: synchronized ITC with CPU %u (last diff %ld cycles, "
342 "maxerr %lu cycles)\n", smp_processor_id(), master, delta, rt);
343}
344
345/*
346 * Ideally sets up per-cpu profiling hooks. Doesn't do much now...
347 */
348static inline void smp_setup_percpu_timer(void)
349{
350}
351
352static void
353smp_callin (void)
354{
355 int cpuid, phys_id, itc_master;
356 struct cpuinfo_ia64 *last_cpuinfo, *this_cpuinfo;
357 extern void ia64_init_itm(void);
358 extern volatile int time_keeper_id;
359
360#ifdef CONFIG_PERFMON
361 extern void pfm_init_percpu(void);
362#endif
363
364 cpuid = smp_processor_id();
365 phys_id = hard_smp_processor_id();
366 itc_master = time_keeper_id;
367
368 if (cpu_online(cpuid)) {
369 printk(KERN_ERR "huh, phys CPU#0x%x, CPU#0x%x already present??\n",
370 phys_id, cpuid);
371 BUG();
372 }
373
374 fix_b0_for_bsp();
375
376 /*
377 * numa_node_id() works after this.
378 */
379 set_numa_node(cpu_to_node_map[cpuid]);
380 set_numa_mem(local_memory_node(cpu_to_node_map[cpuid]));
381
382 spin_lock(&vector_lock);
383 /* Setup the per cpu irq handling data structures */
384 __setup_vector_irq(cpuid);
385 notify_cpu_starting(cpuid);
386 set_cpu_online(cpuid, true);
387 per_cpu(cpu_state, cpuid) = CPU_ONLINE;
388 spin_unlock(&vector_lock);
389
390 smp_setup_percpu_timer();
391
392 ia64_mca_cmc_vector_setup(); /* Setup vector on AP */
393
394#ifdef CONFIG_PERFMON
395 pfm_init_percpu();
396#endif
397
398 local_irq_enable();
399
400 if (!(sal_platform_features & IA64_SAL_PLATFORM_FEATURE_ITC_DRIFT)) {
401 /*
402 * Synchronize the ITC with the BP. Need to do this after irqs are
403 * enabled because ia64_sync_itc() calls smp_call_function_single(), which
404 * calls spin_unlock_bh(), which calls spin_unlock_bh(), which calls
405 * local_bh_enable(), which bugs out if irqs are not enabled...
406 */
407 Dprintk("Going to syncup ITC with ITC Master.\n");
408 ia64_sync_itc(itc_master);
409 }
410
411 /*
412 * Get our bogomips.
413 */
414 ia64_init_itm();
415
416 /*
417 * Delay calibration can be skipped if new processor is identical to the
418 * previous processor.
419 */
420 last_cpuinfo = cpu_data(cpuid - 1);
421 this_cpuinfo = local_cpu_data;
422 if (last_cpuinfo->itc_freq != this_cpuinfo->itc_freq ||
423 last_cpuinfo->proc_freq != this_cpuinfo->proc_freq ||
424 last_cpuinfo->features != this_cpuinfo->features ||
425 last_cpuinfo->revision != this_cpuinfo->revision ||
426 last_cpuinfo->family != this_cpuinfo->family ||
427 last_cpuinfo->archrev != this_cpuinfo->archrev ||
428 last_cpuinfo->model != this_cpuinfo->model)
429 calibrate_delay();
430 local_cpu_data->loops_per_jiffy = loops_per_jiffy;
431
432 /*
433 * Allow the master to continue.
434 */
435 cpumask_set_cpu(cpuid, &cpu_callin_map);
436 Dprintk("Stack on CPU %d at about %p\n",cpuid, &cpuid);
437}
438
439
440/*
441 * Activate a secondary processor. head.S calls this.
442 */
443int
444start_secondary (void *unused)
445{
446 /* Early console may use I/O ports */
447 ia64_set_kr(IA64_KR_IO_BASE, __pa(ia64_iobase));
448#ifndef CONFIG_PRINTK_TIME
449 Dprintk("start_secondary: starting CPU 0x%x\n", hard_smp_processor_id());
450#endif
451 efi_map_pal_code();
452 cpu_init();
453 preempt_disable();
454 smp_callin();
455
456 cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
457 return 0;
458}
459
460static int
461do_boot_cpu (int sapicid, int cpu, struct task_struct *idle)
462{
463 int timeout;
464
465 task_for_booting_cpu = idle;
466 Dprintk("Sending wakeup vector %lu to AP 0x%x/0x%x.\n", ap_wakeup_vector, cpu, sapicid);
467
468 set_brendez_area(cpu);
469 ia64_send_ipi(cpu, ap_wakeup_vector, IA64_IPI_DM_INT, 0);
470
471 /*
472 * Wait 10s total for the AP to start
473 */
474 Dprintk("Waiting on callin_map ...");
475 for (timeout = 0; timeout < 100000; timeout++) {
476 if (cpumask_test_cpu(cpu, &cpu_callin_map))
477 break; /* It has booted */
478 barrier(); /* Make sure we re-read cpu_callin_map */
479 udelay(100);
480 }
481 Dprintk("\n");
482
483 if (!cpumask_test_cpu(cpu, &cpu_callin_map)) {
484 printk(KERN_ERR "Processor 0x%x/0x%x is stuck.\n", cpu, sapicid);
485 ia64_cpu_to_sapicid[cpu] = -1;
486 set_cpu_online(cpu, false); /* was set in smp_callin() */
487 return -EINVAL;
488 }
489 return 0;
490}
491
492static int __init
493decay (char *str)
494{
495 int ticks;
496 get_option (&str, &ticks);
497 return 1;
498}
499
500__setup("decay=", decay);
501
502/*
503 * Initialize the logical CPU number to SAPICID mapping
504 */
505void __init
506smp_build_cpu_map (void)
507{
508 int sapicid, cpu, i;
509 int boot_cpu_id = hard_smp_processor_id();
510
511 for (cpu = 0; cpu < NR_CPUS; cpu++) {
512 ia64_cpu_to_sapicid[cpu] = -1;
513 }
514
515 ia64_cpu_to_sapicid[0] = boot_cpu_id;
516 init_cpu_present(cpumask_of(0));
517 set_cpu_possible(0, true);
518 for (cpu = 1, i = 0; i < smp_boot_data.cpu_count; i++) {
519 sapicid = smp_boot_data.cpu_phys_id[i];
520 if (sapicid == boot_cpu_id)
521 continue;
522 set_cpu_present(cpu, true);
523 set_cpu_possible(cpu, true);
524 ia64_cpu_to_sapicid[cpu] = sapicid;
525 cpu++;
526 }
527}
528
529/*
530 * Cycle through the APs sending Wakeup IPIs to boot each.
531 */
532void __init
533smp_prepare_cpus (unsigned int max_cpus)
534{
535 int boot_cpu_id = hard_smp_processor_id();
536
537 /*
538 * Initialize the per-CPU profiling counter/multiplier
539 */
540
541 smp_setup_percpu_timer();
542
543 cpumask_set_cpu(0, &cpu_callin_map);
544
545 local_cpu_data->loops_per_jiffy = loops_per_jiffy;
546 ia64_cpu_to_sapicid[0] = boot_cpu_id;
547
548 printk(KERN_INFO "Boot processor id 0x%x/0x%x\n", 0, boot_cpu_id);
549
550 current_thread_info()->cpu = 0;
551
552 /*
553 * If SMP should be disabled, then really disable it!
554 */
555 if (!max_cpus) {
556 printk(KERN_INFO "SMP mode deactivated.\n");
557 init_cpu_online(cpumask_of(0));
558 init_cpu_present(cpumask_of(0));
559 init_cpu_possible(cpumask_of(0));
560 return;
561 }
562}
563
564void smp_prepare_boot_cpu(void)
565{
566 set_cpu_online(smp_processor_id(), true);
567 cpumask_set_cpu(smp_processor_id(), &cpu_callin_map);
568 set_numa_node(cpu_to_node_map[smp_processor_id()]);
569 per_cpu(cpu_state, smp_processor_id()) = CPU_ONLINE;
570}
571
572#ifdef CONFIG_HOTPLUG_CPU
573static inline void
574clear_cpu_sibling_map(int cpu)
575{
576 int i;
577
578 for_each_cpu(i, &per_cpu(cpu_sibling_map, cpu))
579 cpumask_clear_cpu(cpu, &per_cpu(cpu_sibling_map, i));
580 for_each_cpu(i, &cpu_core_map[cpu])
581 cpumask_clear_cpu(cpu, &cpu_core_map[i]);
582
583 per_cpu(cpu_sibling_map, cpu) = cpu_core_map[cpu] = CPU_MASK_NONE;
584}
585
586static void
587remove_siblinginfo(int cpu)
588{
589 int last = 0;
590
591 if (cpu_data(cpu)->threads_per_core == 1 &&
592 cpu_data(cpu)->cores_per_socket == 1) {
593 cpumask_clear_cpu(cpu, &cpu_core_map[cpu]);
594 cpumask_clear_cpu(cpu, &per_cpu(cpu_sibling_map, cpu));
595 return;
596 }
597
598 last = (cpumask_weight(&cpu_core_map[cpu]) == 1 ? 1 : 0);
599
600 /* remove it from all sibling map's */
601 clear_cpu_sibling_map(cpu);
602}
603
604extern void fixup_irqs(void);
605
606int migrate_platform_irqs(unsigned int cpu)
607{
608 int new_cpei_cpu;
609 struct irq_data *data = NULL;
610 const struct cpumask *mask;
611 int retval = 0;
612
613 /*
614 * dont permit CPEI target to removed.
615 */
616 if (cpe_vector > 0 && is_cpu_cpei_target(cpu)) {
617 printk ("CPU (%d) is CPEI Target\n", cpu);
618 if (can_cpei_retarget()) {
619 /*
620 * Now re-target the CPEI to a different processor
621 */
622 new_cpei_cpu = cpumask_any(cpu_online_mask);
623 mask = cpumask_of(new_cpei_cpu);
624 set_cpei_target_cpu(new_cpei_cpu);
625 data = irq_get_irq_data(ia64_cpe_irq);
626 /*
627 * Switch for now, immediately, we need to do fake intr
628 * as other interrupts, but need to study CPEI behaviour with
629 * polling before making changes.
630 */
631 if (data && data->chip) {
632 data->chip->irq_disable(data);
633 data->chip->irq_set_affinity(data, mask, false);
634 data->chip->irq_enable(data);
635 printk ("Re-targeting CPEI to cpu %d\n", new_cpei_cpu);
636 }
637 }
638 if (!data) {
639 printk ("Unable to retarget CPEI, offline cpu [%d] failed\n", cpu);
640 retval = -EBUSY;
641 }
642 }
643 return retval;
644}
645
646/* must be called with cpucontrol mutex held */
647int __cpu_disable(void)
648{
649 int cpu = smp_processor_id();
650
651 /*
652 * dont permit boot processor for now
653 */
654 if (cpu == 0 && !bsp_remove_ok) {
655 printk ("Your platform does not support removal of BSP\n");
656 return (-EBUSY);
657 }
658
659 set_cpu_online(cpu, false);
660
661 if (migrate_platform_irqs(cpu)) {
662 set_cpu_online(cpu, true);
663 return -EBUSY;
664 }
665
666 remove_siblinginfo(cpu);
667 fixup_irqs();
668 local_flush_tlb_all();
669 cpumask_clear_cpu(cpu, &cpu_callin_map);
670 return 0;
671}
672
673void __cpu_die(unsigned int cpu)
674{
675 unsigned int i;
676
677 for (i = 0; i < 100; i++) {
678 /* They ack this in play_dead by setting CPU_DEAD */
679 if (per_cpu(cpu_state, cpu) == CPU_DEAD)
680 {
681 printk ("CPU %d is now offline\n", cpu);
682 return;
683 }
684 msleep(100);
685 }
686 printk(KERN_ERR "CPU %u didn't die...\n", cpu);
687}
688#endif /* CONFIG_HOTPLUG_CPU */
689
690void
691smp_cpus_done (unsigned int dummy)
692{
693 int cpu;
694 unsigned long bogosum = 0;
695
696 /*
697 * Allow the user to impress friends.
698 */
699
700 for_each_online_cpu(cpu) {
701 bogosum += cpu_data(cpu)->loops_per_jiffy;
702 }
703
704 printk(KERN_INFO "Total of %d processors activated (%lu.%02lu BogoMIPS).\n",
705 (int)num_online_cpus(), bogosum/(500000/HZ), (bogosum/(5000/HZ))%100);
706}
707
708static inline void set_cpu_sibling_map(int cpu)
709{
710 int i;
711
712 for_each_online_cpu(i) {
713 if ((cpu_data(cpu)->socket_id == cpu_data(i)->socket_id)) {
714 cpumask_set_cpu(i, &cpu_core_map[cpu]);
715 cpumask_set_cpu(cpu, &cpu_core_map[i]);
716 if (cpu_data(cpu)->core_id == cpu_data(i)->core_id) {
717 cpumask_set_cpu(i,
718 &per_cpu(cpu_sibling_map, cpu));
719 cpumask_set_cpu(cpu,
720 &per_cpu(cpu_sibling_map, i));
721 }
722 }
723 }
724}
725
726int
727__cpu_up(unsigned int cpu, struct task_struct *tidle)
728{
729 int ret;
730 int sapicid;
731
732 sapicid = ia64_cpu_to_sapicid[cpu];
733 if (sapicid == -1)
734 return -EINVAL;
735
736 /*
737 * Already booted cpu? not valid anymore since we dont
738 * do idle loop tightspin anymore.
739 */
740 if (cpumask_test_cpu(cpu, &cpu_callin_map))
741 return -EINVAL;
742
743 per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
744 /* Processor goes to start_secondary(), sets online flag */
745 ret = do_boot_cpu(sapicid, cpu, tidle);
746 if (ret < 0)
747 return ret;
748
749 if (cpu_data(cpu)->threads_per_core == 1 &&
750 cpu_data(cpu)->cores_per_socket == 1) {
751 cpumask_set_cpu(cpu, &per_cpu(cpu_sibling_map, cpu));
752 cpumask_set_cpu(cpu, &cpu_core_map[cpu]);
753 return 0;
754 }
755
756 set_cpu_sibling_map(cpu);
757
758 return 0;
759}
760
761/*
762 * Assume that CPUs have been discovered by some platform-dependent interface. For
763 * SoftSDV/Lion, that would be ACPI.
764 *
765 * Setup of the IPI irq handler is done in irq.c:init_IRQ_SMP().
766 */
767void __init
768init_smp_config(void)
769{
770 struct fptr {
771 unsigned long fp;
772 unsigned long gp;
773 } *ap_startup;
774 long sal_ret;
775
776 /* Tell SAL where to drop the APs. */
777 ap_startup = (struct fptr *) start_ap;
778 sal_ret = ia64_sal_set_vectors(SAL_VECTOR_OS_BOOT_RENDEZ,
779 ia64_tpa(ap_startup->fp), ia64_tpa(ap_startup->gp), 0, 0, 0, 0);
780 if (sal_ret < 0)
781 printk(KERN_ERR "SMP: Can't set SAL AP Boot Rendezvous: %s\n",
782 ia64_sal_strerror(sal_ret));
783}
784
785/*
786 * identify_siblings(cpu) gets called from identify_cpu. This populates the
787 * information related to logical execution units in per_cpu_data structure.
788 */
789void identify_siblings(struct cpuinfo_ia64 *c)
790{
791 long status;
792 u16 pltid;
793 pal_logical_to_physical_t info;
794
795 status = ia64_pal_logical_to_phys(-1, &info);
796 if (status != PAL_STATUS_SUCCESS) {
797 if (status != PAL_STATUS_UNIMPLEMENTED) {
798 printk(KERN_ERR
799 "ia64_pal_logical_to_phys failed with %ld\n",
800 status);
801 return;
802 }
803
804 info.overview_ppid = 0;
805 info.overview_cpp = 1;
806 info.overview_tpc = 1;
807 }
808
809 status = ia64_sal_physical_id_info(&pltid);
810 if (status != PAL_STATUS_SUCCESS) {
811 if (status != PAL_STATUS_UNIMPLEMENTED)
812 printk(KERN_ERR
813 "ia64_sal_pltid failed with %ld\n",
814 status);
815 return;
816 }
817
818 c->socket_id = (pltid << 8) | info.overview_ppid;
819
820 if (info.overview_cpp == 1 && info.overview_tpc == 1)
821 return;
822
823 c->cores_per_socket = info.overview_cpp;
824 c->threads_per_core = info.overview_tpc;
825 c->num_log = info.overview_num_log;
826
827 c->core_id = info.log1_cid;
828 c->thread_id = info.log1_tid;
829}
830
831/*
832 * returns non zero, if multi-threading is enabled
833 * on at least one physical package. Due to hotplug cpu
834 * and (maxcpus=), all threads may not necessarily be enabled
835 * even though the processor supports multi-threading.
836 */
837int is_multithreading_enabled(void)
838{
839 int i, j;
840
841 for_each_present_cpu(i) {
842 for_each_present_cpu(j) {
843 if (j == i)
844 continue;
845 if ((cpu_data(j)->socket_id == cpu_data(i)->socket_id)) {
846 if (cpu_data(j)->core_id == cpu_data(i)->core_id)
847 return 1;
848 }
849 }
850 }
851 return 0;
852}
853EXPORT_SYMBOL_GPL(is_multithreading_enabled);
1/*
2 * SMP boot-related support
3 *
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>
11 *
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
23 */
24
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>
42
43#include <linux/atomic.h>
44#include <asm/cache.h>
45#include <asm/current.h>
46#include <asm/delay.h>
47#include <asm/io.h>
48#include <asm/irq.h>
49#include <asm/machvec.h>
50#include <asm/mca.h>
51#include <asm/page.h>
52#include <asm/paravirt.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>
62
63#define SMP_DEBUG 0
64
65#if SMP_DEBUG
66#define Dprintk(x...) printk(x)
67#else
68#define Dprintk(x...)
69#endif
70
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
77
78/*
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.
82 */
83struct task_struct *idle_thread_array[NR_CPUS];
84
85/*
86 * Global array allocated for NR_CPUS at boot time
87 */
88struct sal_to_os_boot sal_boot_rendez_state[NR_CPUS];
89
90/*
91 * start_ap in head.S uses this to store current booting cpu
92 * info.
93 */
94struct sal_to_os_boot *sal_state_for_booting_cpu = &sal_boot_rendez_state[0];
95
96#define set_brendez_area(x) (sal_state_for_booting_cpu = &sal_boot_rendez_state[(x)]);
97
98#define get_idle_for_cpu(x) (idle_thread_array[(x)])
99#define set_idle_for_cpu(x,p) (idle_thread_array[(x)] = (p))
100
101#else
102
103#define get_idle_for_cpu(x) (NULL)
104#define set_idle_for_cpu(x,p)
105#define set_brendez_area(x)
106#endif
107
108
109/*
110 * ITC synchronization related stuff:
111 */
112#define MASTER (0)
113#define SLAVE (SMP_CACHE_BYTES/8)
114
115#define NUM_ROUNDS 64 /* magic value */
116#define NUM_ITERS 5 /* likewise */
117
118static DEFINE_SPINLOCK(itc_sync_lock);
119static volatile unsigned long go[SLAVE + 1];
120
121#define DEBUG_ITC_SYNC 0
122
123extern void start_ap (void);
124extern unsigned long ia64_iobase;
125
126struct task_struct *task_for_booting_cpu;
127
128/*
129 * State for each CPU
130 */
131DEFINE_PER_CPU(int, cpu_state);
132
133cpumask_t cpu_core_map[NR_CPUS] __cacheline_aligned;
134EXPORT_SYMBOL(cpu_core_map);
135DEFINE_PER_CPU_SHARED_ALIGNED(cpumask_t, cpu_sibling_map);
136EXPORT_PER_CPU_SYMBOL(cpu_sibling_map);
137
138int smp_num_siblings = 1;
139
140/* which logical CPU number maps to which CPU (physical APIC ID) */
141volatile int ia64_cpu_to_sapicid[NR_CPUS];
142EXPORT_SYMBOL(ia64_cpu_to_sapicid);
143
144static volatile cpumask_t cpu_callin_map;
145
146struct smp_boot_data smp_boot_data __initdata;
147
148unsigned long ap_wakeup_vector = -1; /* External Int use to wakeup APs */
149
150char __initdata no_int_routing;
151
152unsigned char smp_int_redirect; /* are INT and IPI redirectable by the chipset? */
153
154#ifdef CONFIG_FORCE_CPEI_RETARGET
155#define CPEI_OVERRIDE_DEFAULT (1)
156#else
157#define CPEI_OVERRIDE_DEFAULT (0)
158#endif
159
160unsigned int force_cpei_retarget = CPEI_OVERRIDE_DEFAULT;
161
162static int __init
163cmdl_force_cpei(char *str)
164{
165 int value=0;
166
167 get_option (&str, &value);
168 force_cpei_retarget = value;
169
170 return 1;
171}
172
173__setup("force_cpei=", cmdl_force_cpei);
174
175static int __init
176nointroute (char *str)
177{
178 no_int_routing = 1;
179 printk ("no_int_routing on\n");
180 return 1;
181}
182
183__setup("nointroute", nointroute);
184
185static void fix_b0_for_bsp(void)
186{
187#ifdef CONFIG_HOTPLUG_CPU
188 int cpuid;
189 static int fix_bsp_b0 = 1;
190
191 cpuid = smp_processor_id();
192
193 /*
194 * Cache the b0 value on the first AP that comes up
195 */
196 if (!(fix_bsp_b0 && cpuid))
197 return;
198
199 sal_boot_rendez_state[0].br[0] = sal_boot_rendez_state[cpuid].br[0];
200 printk ("Fixed BSP b0 value from CPU %d\n", cpuid);
201
202 fix_bsp_b0 = 0;
203#endif
204}
205
206void
207sync_master (void *arg)
208{
209 unsigned long flags, i;
210
211 go[MASTER] = 0;
212
213 local_irq_save(flags);
214 {
215 for (i = 0; i < NUM_ROUNDS*NUM_ITERS; ++i) {
216 while (!go[MASTER])
217 cpu_relax();
218 go[MASTER] = 0;
219 go[SLAVE] = ia64_get_itc();
220 }
221 }
222 local_irq_restore(flags);
223}
224
225/*
226 * Return the number of cycles by which our itc differs from the itc on the master
227 * (time-keeper) CPU. A positive number indicates our itc is ahead of the master,
228 * negative that it is behind.
229 */
230static inline long
231get_delta (long *rt, long *master)
232{
233 unsigned long best_t0 = 0, best_t1 = ~0UL, best_tm = 0;
234 unsigned long tcenter, t0, t1, tm;
235 long i;
236
237 for (i = 0; i < NUM_ITERS; ++i) {
238 t0 = ia64_get_itc();
239 go[MASTER] = 1;
240 while (!(tm = go[SLAVE]))
241 cpu_relax();
242 go[SLAVE] = 0;
243 t1 = ia64_get_itc();
244
245 if (t1 - t0 < best_t1 - best_t0)
246 best_t0 = t0, best_t1 = t1, best_tm = tm;
247 }
248
249 *rt = best_t1 - best_t0;
250 *master = best_tm - best_t0;
251
252 /* average best_t0 and best_t1 without overflow: */
253 tcenter = (best_t0/2 + best_t1/2);
254 if (best_t0 % 2 + best_t1 % 2 == 2)
255 ++tcenter;
256 return tcenter - best_tm;
257}
258
259/*
260 * Synchronize ar.itc of the current (slave) CPU with the ar.itc of the MASTER CPU
261 * (normally the time-keeper CPU). We use a closed loop to eliminate the possibility of
262 * unaccounted-for errors (such as getting a machine check in the middle of a calibration
263 * step). The basic idea is for the slave to ask the master what itc value it has and to
264 * read its own itc before and after the master responds. Each iteration gives us three
265 * timestamps:
266 *
267 * slave master
268 *
269 * t0 ---\
270 * ---\
271 * --->
272 * tm
273 * /---
274 * /---
275 * t1 <---
276 *
277 *
278 * The goal is to adjust the slave's ar.itc such that tm falls exactly half-way between t0
279 * and t1. If we achieve this, the clocks are synchronized provided the interconnect
280 * between the slave and the master is symmetric. Even if the interconnect were
281 * asymmetric, we would still know that the synchronization error is smaller than the
282 * roundtrip latency (t0 - t1).
283 *
284 * When the interconnect is quiet and symmetric, this lets us synchronize the itc to
285 * within one or two cycles. However, we can only *guarantee* that the synchronization is
286 * accurate to within a round-trip time, which is typically in the range of several
287 * hundred cycles (e.g., ~500 cycles). In practice, this means that the itc's are usually
288 * almost perfectly synchronized, but we shouldn't assume that the accuracy is much better
289 * than half a micro second or so.
290 */
291void
292ia64_sync_itc (unsigned int master)
293{
294 long i, delta, adj, adjust_latency = 0, done = 0;
295 unsigned long flags, rt, master_time_stamp, bound;
296#if DEBUG_ITC_SYNC
297 struct {
298 long rt; /* roundtrip time */
299 long master; /* master's timestamp */
300 long diff; /* difference between midpoint and master's timestamp */
301 long lat; /* estimate of itc adjustment latency */
302 } t[NUM_ROUNDS];
303#endif
304
305 /*
306 * Make sure local timer ticks are disabled while we sync. If
307 * they were enabled, we'd have to worry about nasty issues
308 * like setting the ITC ahead of (or a long time before) the
309 * next scheduled tick.
310 */
311 BUG_ON((ia64_get_itv() & (1 << 16)) == 0);
312
313 go[MASTER] = 1;
314
315 if (smp_call_function_single(master, sync_master, NULL, 0) < 0) {
316 printk(KERN_ERR "sync_itc: failed to get attention of CPU %u!\n", master);
317 return;
318 }
319
320 while (go[MASTER])
321 cpu_relax(); /* wait for master to be ready */
322
323 spin_lock_irqsave(&itc_sync_lock, flags);
324 {
325 for (i = 0; i < NUM_ROUNDS; ++i) {
326 delta = get_delta(&rt, &master_time_stamp);
327 if (delta == 0) {
328 done = 1; /* let's lock on to this... */
329 bound = rt;
330 }
331
332 if (!done) {
333 if (i > 0) {
334 adjust_latency += -delta;
335 adj = -delta + adjust_latency/4;
336 } else
337 adj = -delta;
338
339 ia64_set_itc(ia64_get_itc() + adj);
340 }
341#if DEBUG_ITC_SYNC
342 t[i].rt = rt;
343 t[i].master = master_time_stamp;
344 t[i].diff = delta;
345 t[i].lat = adjust_latency/4;
346#endif
347 }
348 }
349 spin_unlock_irqrestore(&itc_sync_lock, flags);
350
351#if DEBUG_ITC_SYNC
352 for (i = 0; i < NUM_ROUNDS; ++i)
353 printk("rt=%5ld master=%5ld diff=%5ld adjlat=%5ld\n",
354 t[i].rt, t[i].master, t[i].diff, t[i].lat);
355#endif
356
357 printk(KERN_INFO "CPU %d: synchronized ITC with CPU %u (last diff %ld cycles, "
358 "maxerr %lu cycles)\n", smp_processor_id(), master, delta, rt);
359}
360
361/*
362 * Ideally sets up per-cpu profiling hooks. Doesn't do much now...
363 */
364static inline void __devinit
365smp_setup_percpu_timer (void)
366{
367}
368
369static void __cpuinit
370smp_callin (void)
371{
372 int cpuid, phys_id, itc_master;
373 struct cpuinfo_ia64 *last_cpuinfo, *this_cpuinfo;
374 extern void ia64_init_itm(void);
375 extern volatile int time_keeper_id;
376
377#ifdef CONFIG_PERFMON
378 extern void pfm_init_percpu(void);
379#endif
380
381 cpuid = smp_processor_id();
382 phys_id = hard_smp_processor_id();
383 itc_master = time_keeper_id;
384
385 if (cpu_online(cpuid)) {
386 printk(KERN_ERR "huh, phys CPU#0x%x, CPU#0x%x already present??\n",
387 phys_id, cpuid);
388 BUG();
389 }
390
391 fix_b0_for_bsp();
392
393 /*
394 * numa_node_id() works after this.
395 */
396 set_numa_node(cpu_to_node_map[cpuid]);
397 set_numa_mem(local_memory_node(cpu_to_node_map[cpuid]));
398
399 ipi_call_lock_irq();
400 spin_lock(&vector_lock);
401 /* Setup the per cpu irq handling data structures */
402 __setup_vector_irq(cpuid);
403 notify_cpu_starting(cpuid);
404 cpu_set(cpuid, cpu_online_map);
405 per_cpu(cpu_state, cpuid) = CPU_ONLINE;
406 spin_unlock(&vector_lock);
407 ipi_call_unlock_irq();
408
409 smp_setup_percpu_timer();
410
411 ia64_mca_cmc_vector_setup(); /* Setup vector on AP */
412
413#ifdef CONFIG_PERFMON
414 pfm_init_percpu();
415#endif
416
417 local_irq_enable();
418
419 if (!(sal_platform_features & IA64_SAL_PLATFORM_FEATURE_ITC_DRIFT)) {
420 /*
421 * Synchronize the ITC with the BP. Need to do this after irqs are
422 * enabled because ia64_sync_itc() calls smp_call_function_single(), which
423 * calls spin_unlock_bh(), which calls spin_unlock_bh(), which calls
424 * local_bh_enable(), which bugs out if irqs are not enabled...
425 */
426 Dprintk("Going to syncup ITC with ITC Master.\n");
427 ia64_sync_itc(itc_master);
428 }
429
430 /*
431 * Get our bogomips.
432 */
433 ia64_init_itm();
434
435 /*
436 * Delay calibration can be skipped if new processor is identical to the
437 * previous processor.
438 */
439 last_cpuinfo = cpu_data(cpuid - 1);
440 this_cpuinfo = local_cpu_data;
441 if (last_cpuinfo->itc_freq != this_cpuinfo->itc_freq ||
442 last_cpuinfo->proc_freq != this_cpuinfo->proc_freq ||
443 last_cpuinfo->features != this_cpuinfo->features ||
444 last_cpuinfo->revision != this_cpuinfo->revision ||
445 last_cpuinfo->family != this_cpuinfo->family ||
446 last_cpuinfo->archrev != this_cpuinfo->archrev ||
447 last_cpuinfo->model != this_cpuinfo->model)
448 calibrate_delay();
449 local_cpu_data->loops_per_jiffy = loops_per_jiffy;
450
451 /*
452 * Allow the master to continue.
453 */
454 cpu_set(cpuid, cpu_callin_map);
455 Dprintk("Stack on CPU %d at about %p\n",cpuid, &cpuid);
456}
457
458
459/*
460 * Activate a secondary processor. head.S calls this.
461 */
462int __cpuinit
463start_secondary (void *unused)
464{
465 /* Early console may use I/O ports */
466 ia64_set_kr(IA64_KR_IO_BASE, __pa(ia64_iobase));
467#ifndef CONFIG_PRINTK_TIME
468 Dprintk("start_secondary: starting CPU 0x%x\n", hard_smp_processor_id());
469#endif
470 efi_map_pal_code();
471 cpu_init();
472 preempt_disable();
473 smp_callin();
474
475 cpu_idle();
476 return 0;
477}
478
479struct pt_regs * __cpuinit idle_regs(struct pt_regs *regs)
480{
481 return NULL;
482}
483
484struct create_idle {
485 struct work_struct work;
486 struct task_struct *idle;
487 struct completion done;
488 int cpu;
489};
490
491void __cpuinit
492do_fork_idle(struct work_struct *work)
493{
494 struct create_idle *c_idle =
495 container_of(work, struct create_idle, work);
496
497 c_idle->idle = fork_idle(c_idle->cpu);
498 complete(&c_idle->done);
499}
500
501static int __cpuinit
502do_boot_cpu (int sapicid, int cpu)
503{
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),
509 };
510
511 /*
512 * We can't use kernel_thread since we must avoid to
513 * reschedule the child.
514 */
515 c_idle.idle = get_idle_for_cpu(cpu);
516 if (c_idle.idle) {
517 init_idle(c_idle.idle, cpu);
518 goto do_rest;
519 }
520
521 schedule_work(&c_idle.work);
522 wait_for_completion(&c_idle.done);
523
524 if (IS_ERR(c_idle.idle))
525 panic("failed fork for CPU %d", cpu);
526
527 set_idle_for_cpu(cpu, c_idle.idle);
528
529do_rest:
530 task_for_booting_cpu = c_idle.idle;
531
532 Dprintk("Sending wakeup vector %lu to AP 0x%x/0x%x.\n", ap_wakeup_vector, cpu, sapicid);
533
534 set_brendez_area(cpu);
535 platform_send_ipi(cpu, ap_wakeup_vector, IA64_IPI_DM_INT, 0);
536
537 /*
538 * Wait 10s total for the AP to start
539 */
540 Dprintk("Waiting on callin_map ...");
541 for (timeout = 0; timeout < 100000; timeout++) {
542 if (cpu_isset(cpu, cpu_callin_map))
543 break; /* It has booted */
544 udelay(100);
545 }
546 Dprintk("\n");
547
548 if (!cpu_isset(cpu, cpu_callin_map)) {
549 printk(KERN_ERR "Processor 0x%x/0x%x is stuck.\n", cpu, sapicid);
550 ia64_cpu_to_sapicid[cpu] = -1;
551 cpu_clear(cpu, cpu_online_map); /* was set in smp_callin() */
552 return -EINVAL;
553 }
554 return 0;
555}
556
557static int __init
558decay (char *str)
559{
560 int ticks;
561 get_option (&str, &ticks);
562 return 1;
563}
564
565__setup("decay=", decay);
566
567/*
568 * Initialize the logical CPU number to SAPICID mapping
569 */
570void __init
571smp_build_cpu_map (void)
572{
573 int sapicid, cpu, i;
574 int boot_cpu_id = hard_smp_processor_id();
575
576 for (cpu = 0; cpu < NR_CPUS; cpu++) {
577 ia64_cpu_to_sapicid[cpu] = -1;
578 }
579
580 ia64_cpu_to_sapicid[0] = boot_cpu_id;
581 cpus_clear(cpu_present_map);
582 set_cpu_present(0, true);
583 set_cpu_possible(0, true);
584 for (cpu = 1, i = 0; i < smp_boot_data.cpu_count; i++) {
585 sapicid = smp_boot_data.cpu_phys_id[i];
586 if (sapicid == boot_cpu_id)
587 continue;
588 set_cpu_present(cpu, true);
589 set_cpu_possible(cpu, true);
590 ia64_cpu_to_sapicid[cpu] = sapicid;
591 cpu++;
592 }
593}
594
595/*
596 * Cycle through the APs sending Wakeup IPIs to boot each.
597 */
598void __init
599smp_prepare_cpus (unsigned int max_cpus)
600{
601 int boot_cpu_id = hard_smp_processor_id();
602
603 /*
604 * Initialize the per-CPU profiling counter/multiplier
605 */
606
607 smp_setup_percpu_timer();
608
609 /*
610 * We have the boot CPU online for sure.
611 */
612 cpu_set(0, cpu_online_map);
613 cpu_set(0, cpu_callin_map);
614
615 local_cpu_data->loops_per_jiffy = loops_per_jiffy;
616 ia64_cpu_to_sapicid[0] = boot_cpu_id;
617
618 printk(KERN_INFO "Boot processor id 0x%x/0x%x\n", 0, boot_cpu_id);
619
620 current_thread_info()->cpu = 0;
621
622 /*
623 * If SMP should be disabled, then really disable it!
624 */
625 if (!max_cpus) {
626 printk(KERN_INFO "SMP mode deactivated.\n");
627 init_cpu_online(cpumask_of(0));
628 init_cpu_present(cpumask_of(0));
629 init_cpu_possible(cpumask_of(0));
630 return;
631 }
632}
633
634void __devinit smp_prepare_boot_cpu(void)
635{
636 cpu_set(smp_processor_id(), cpu_online_map);
637 cpu_set(smp_processor_id(), cpu_callin_map);
638 set_numa_node(cpu_to_node_map[smp_processor_id()]);
639 per_cpu(cpu_state, smp_processor_id()) = CPU_ONLINE;
640 paravirt_post_smp_prepare_boot_cpu();
641}
642
643#ifdef CONFIG_HOTPLUG_CPU
644static inline void
645clear_cpu_sibling_map(int cpu)
646{
647 int i;
648
649 for_each_cpu_mask(i, per_cpu(cpu_sibling_map, cpu))
650 cpu_clear(cpu, per_cpu(cpu_sibling_map, i));
651 for_each_cpu_mask(i, cpu_core_map[cpu])
652 cpu_clear(cpu, cpu_core_map[i]);
653
654 per_cpu(cpu_sibling_map, cpu) = cpu_core_map[cpu] = CPU_MASK_NONE;
655}
656
657static void
658remove_siblinginfo(int cpu)
659{
660 int last = 0;
661
662 if (cpu_data(cpu)->threads_per_core == 1 &&
663 cpu_data(cpu)->cores_per_socket == 1) {
664 cpu_clear(cpu, cpu_core_map[cpu]);
665 cpu_clear(cpu, per_cpu(cpu_sibling_map, cpu));
666 return;
667 }
668
669 last = (cpus_weight(cpu_core_map[cpu]) == 1 ? 1 : 0);
670
671 /* remove it from all sibling map's */
672 clear_cpu_sibling_map(cpu);
673}
674
675extern void fixup_irqs(void);
676
677int migrate_platform_irqs(unsigned int cpu)
678{
679 int new_cpei_cpu;
680 struct irq_data *data = NULL;
681 const struct cpumask *mask;
682 int retval = 0;
683
684 /*
685 * dont permit CPEI target to removed.
686 */
687 if (cpe_vector > 0 && is_cpu_cpei_target(cpu)) {
688 printk ("CPU (%d) is CPEI Target\n", cpu);
689 if (can_cpei_retarget()) {
690 /*
691 * Now re-target the CPEI to a different processor
692 */
693 new_cpei_cpu = any_online_cpu(cpu_online_map);
694 mask = cpumask_of(new_cpei_cpu);
695 set_cpei_target_cpu(new_cpei_cpu);
696 data = irq_get_irq_data(ia64_cpe_irq);
697 /*
698 * Switch for now, immediately, we need to do fake intr
699 * as other interrupts, but need to study CPEI behaviour with
700 * polling before making changes.
701 */
702 if (data && data->chip) {
703 data->chip->irq_disable(data);
704 data->chip->irq_set_affinity(data, mask, false);
705 data->chip->irq_enable(data);
706 printk ("Re-targeting CPEI to cpu %d\n", new_cpei_cpu);
707 }
708 }
709 if (!data) {
710 printk ("Unable to retarget CPEI, offline cpu [%d] failed\n", cpu);
711 retval = -EBUSY;
712 }
713 }
714 return retval;
715}
716
717/* must be called with cpucontrol mutex held */
718int __cpu_disable(void)
719{
720 int cpu = smp_processor_id();
721
722 /*
723 * dont permit boot processor for now
724 */
725 if (cpu == 0 && !bsp_remove_ok) {
726 printk ("Your platform does not support removal of BSP\n");
727 return (-EBUSY);
728 }
729
730 if (ia64_platform_is("sn2")) {
731 if (!sn_cpu_disable_allowed(cpu))
732 return -EBUSY;
733 }
734
735 cpu_clear(cpu, cpu_online_map);
736
737 if (migrate_platform_irqs(cpu)) {
738 cpu_set(cpu, cpu_online_map);
739 return -EBUSY;
740 }
741
742 remove_siblinginfo(cpu);
743 fixup_irqs();
744 local_flush_tlb_all();
745 cpu_clear(cpu, cpu_callin_map);
746 return 0;
747}
748
749void __cpu_die(unsigned int cpu)
750{
751 unsigned int i;
752
753 for (i = 0; i < 100; i++) {
754 /* They ack this in play_dead by setting CPU_DEAD */
755 if (per_cpu(cpu_state, cpu) == CPU_DEAD)
756 {
757 printk ("CPU %d is now offline\n", cpu);
758 return;
759 }
760 msleep(100);
761 }
762 printk(KERN_ERR "CPU %u didn't die...\n", cpu);
763}
764#endif /* CONFIG_HOTPLUG_CPU */
765
766void
767smp_cpus_done (unsigned int dummy)
768{
769 int cpu;
770 unsigned long bogosum = 0;
771
772 /*
773 * Allow the user to impress friends.
774 */
775
776 for_each_online_cpu(cpu) {
777 bogosum += cpu_data(cpu)->loops_per_jiffy;
778 }
779
780 printk(KERN_INFO "Total of %d processors activated (%lu.%02lu BogoMIPS).\n",
781 (int)num_online_cpus(), bogosum/(500000/HZ), (bogosum/(5000/HZ))%100);
782}
783
784static inline void __devinit
785set_cpu_sibling_map(int cpu)
786{
787 int i;
788
789 for_each_online_cpu(i) {
790 if ((cpu_data(cpu)->socket_id == cpu_data(i)->socket_id)) {
791 cpu_set(i, cpu_core_map[cpu]);
792 cpu_set(cpu, cpu_core_map[i]);
793 if (cpu_data(cpu)->core_id == cpu_data(i)->core_id) {
794 cpu_set(i, per_cpu(cpu_sibling_map, cpu));
795 cpu_set(cpu, per_cpu(cpu_sibling_map, i));
796 }
797 }
798 }
799}
800
801int __cpuinit
802__cpu_up (unsigned int cpu)
803{
804 int ret;
805 int sapicid;
806
807 sapicid = ia64_cpu_to_sapicid[cpu];
808 if (sapicid == -1)
809 return -EINVAL;
810
811 /*
812 * Already booted cpu? not valid anymore since we dont
813 * do idle loop tightspin anymore.
814 */
815 if (cpu_isset(cpu, cpu_callin_map))
816 return -EINVAL;
817
818 per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
819 /* Processor goes to start_secondary(), sets online flag */
820 ret = do_boot_cpu(sapicid, cpu);
821 if (ret < 0)
822 return ret;
823
824 if (cpu_data(cpu)->threads_per_core == 1 &&
825 cpu_data(cpu)->cores_per_socket == 1) {
826 cpu_set(cpu, per_cpu(cpu_sibling_map, cpu));
827 cpu_set(cpu, cpu_core_map[cpu]);
828 return 0;
829 }
830
831 set_cpu_sibling_map(cpu);
832
833 return 0;
834}
835
836/*
837 * Assume that CPUs have been discovered by some platform-dependent interface. For
838 * SoftSDV/Lion, that would be ACPI.
839 *
840 * Setup of the IPI irq handler is done in irq.c:init_IRQ_SMP().
841 */
842void __init
843init_smp_config(void)
844{
845 struct fptr {
846 unsigned long fp;
847 unsigned long gp;
848 } *ap_startup;
849 long sal_ret;
850
851 /* Tell SAL where to drop the APs. */
852 ap_startup = (struct fptr *) start_ap;
853 sal_ret = ia64_sal_set_vectors(SAL_VECTOR_OS_BOOT_RENDEZ,
854 ia64_tpa(ap_startup->fp), ia64_tpa(ap_startup->gp), 0, 0, 0, 0);
855 if (sal_ret < 0)
856 printk(KERN_ERR "SMP: Can't set SAL AP Boot Rendezvous: %s\n",
857 ia64_sal_strerror(sal_ret));
858}
859
860/*
861 * identify_siblings(cpu) gets called from identify_cpu. This populates the
862 * information related to logical execution units in per_cpu_data structure.
863 */
864void __devinit
865identify_siblings(struct cpuinfo_ia64 *c)
866{
867 long status;
868 u16 pltid;
869 pal_logical_to_physical_t info;
870
871 status = ia64_pal_logical_to_phys(-1, &info);
872 if (status != PAL_STATUS_SUCCESS) {
873 if (status != PAL_STATUS_UNIMPLEMENTED) {
874 printk(KERN_ERR
875 "ia64_pal_logical_to_phys failed with %ld\n",
876 status);
877 return;
878 }
879
880 info.overview_ppid = 0;
881 info.overview_cpp = 1;
882 info.overview_tpc = 1;
883 }
884
885 status = ia64_sal_physical_id_info(&pltid);
886 if (status != PAL_STATUS_SUCCESS) {
887 if (status != PAL_STATUS_UNIMPLEMENTED)
888 printk(KERN_ERR
889 "ia64_sal_pltid failed with %ld\n",
890 status);
891 return;
892 }
893
894 c->socket_id = (pltid << 8) | info.overview_ppid;
895
896 if (info.overview_cpp == 1 && info.overview_tpc == 1)
897 return;
898
899 c->cores_per_socket = info.overview_cpp;
900 c->threads_per_core = info.overview_tpc;
901 c->num_log = info.overview_num_log;
902
903 c->core_id = info.log1_cid;
904 c->thread_id = info.log1_tid;
905}
906
907/*
908 * returns non zero, if multi-threading is enabled
909 * on at least one physical package. Due to hotplug cpu
910 * and (maxcpus=), all threads may not necessarily be enabled
911 * even though the processor supports multi-threading.
912 */
913int is_multithreading_enabled(void)
914{
915 int i, j;
916
917 for_each_present_cpu(i) {
918 for_each_present_cpu(j) {
919 if (j == i)
920 continue;
921 if ((cpu_data(j)->socket_id == cpu_data(i)->socket_id)) {
922 if (cpu_data(j)->core_id == cpu_data(i)->core_id)
923 return 1;
924 }
925 }
926 }
927 return 0;
928}
929EXPORT_SYMBOL_GPL(is_multithreading_enabled);