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4cedb334
GOC
1/*
2 * x86 SMP booting functions
3 *
87c6fe26 4 * (c) 1995 Alan Cox, Building #3 <alan@lxorguk.ukuu.org.uk>
8f47e163 5 * (c) 1998, 1999, 2000, 2009 Ingo Molnar <mingo@redhat.com>
4cedb334
GOC
6 * Copyright 2001 Andi Kleen, SuSE Labs.
7 *
8 * Much of the core SMP work is based on previous work by Thomas Radke, to
9 * whom a great many thanks are extended.
10 *
11 * Thanks to Intel for making available several different Pentium,
12 * Pentium Pro and Pentium-II/Xeon MP machines.
13 * Original development of Linux SMP code supported by Caldera.
14 *
15 * This code is released under the GNU General Public License version 2 or
16 * later.
17 *
18 * Fixes
19 * Felix Koop : NR_CPUS used properly
20 * Jose Renau : Handle single CPU case.
21 * Alan Cox : By repeated request 8) - Total BogoMIPS report.
22 * Greg Wright : Fix for kernel stacks panic.
23 * Erich Boleyn : MP v1.4 and additional changes.
24 * Matthias Sattler : Changes for 2.1 kernel map.
25 * Michel Lespinasse : Changes for 2.1 kernel map.
26 * Michael Chastain : Change trampoline.S to gnu as.
27 * Alan Cox : Dumb bug: 'B' step PPro's are fine
28 * Ingo Molnar : Added APIC timers, based on code
29 * from Jose Renau
30 * Ingo Molnar : various cleanups and rewrites
31 * Tigran Aivazian : fixed "0.00 in /proc/uptime on SMP" bug.
32 * Maciej W. Rozycki : Bits for genuine 82489DX APICs
33 * Andi Kleen : Changed for SMP boot into long mode.
34 * Martin J. Bligh : Added support for multi-quad systems
35 * Dave Jones : Report invalid combinations of Athlon CPUs.
36 * Rusty Russell : Hacked into shape for new "hotplug" boot process.
37 * Andi Kleen : Converted to new state machine.
38 * Ashok Raj : CPU hotplug support
39 * Glauber Costa : i386 and x86_64 integration
40 */
41
68a1c3f8
GC
42#include <linux/init.h>
43#include <linux/smp.h>
a355352b 44#include <linux/module.h>
70708a18 45#include <linux/sched.h>
69c18c15 46#include <linux/percpu.h>
91718e8d 47#include <linux/bootmem.h>
cb3c8b90
GOC
48#include <linux/err.h>
49#include <linux/nmi.h>
69575d38 50#include <linux/tboot.h>
35f720c5 51#include <linux/stackprotector.h>
5a0e3ad6 52#include <linux/gfp.h>
69c18c15 53
8aef135c 54#include <asm/acpi.h>
cb3c8b90 55#include <asm/desc.h>
69c18c15
GC
56#include <asm/nmi.h>
57#include <asm/irq.h>
07bbc16a 58#include <asm/idle.h>
e44b7b75 59#include <asm/trampoline.h>
69c18c15
GC
60#include <asm/cpu.h>
61#include <asm/numa.h>
cb3c8b90
GOC
62#include <asm/pgtable.h>
63#include <asm/tlbflush.h>
64#include <asm/mtrr.h>
ea530692 65#include <asm/mwait.h>
7b6aa335 66#include <asm/apic.h>
7167d08e 67#include <asm/io_apic.h>
569712b2 68#include <asm/setup.h>
bdbcdd48 69#include <asm/uv/uv.h>
cb3c8b90 70#include <linux/mc146818rtc.h>
68a1c3f8 71
1164dd00 72#include <asm/smpboot_hooks.h>
b81bb373 73#include <asm/i8259.h>
cb3c8b90 74
a8db8453
GOC
75/* State of each CPU */
76DEFINE_PER_CPU(int, cpu_state) = { 0 };
77
cb3c8b90
GOC
78/* Store all idle threads, this can be reused instead of creating
79* a new thread. Also avoids complicated thread destroy functionality
80* for idle threads.
81*/
82#ifdef CONFIG_HOTPLUG_CPU
83/*
84 * Needed only for CONFIG_HOTPLUG_CPU because __cpuinitdata is
85 * removed after init for !CONFIG_HOTPLUG_CPU.
86 */
87static DEFINE_PER_CPU(struct task_struct *, idle_thread_array);
88#define get_idle_for_cpu(x) (per_cpu(idle_thread_array, x))
89#define set_idle_for_cpu(x, p) (per_cpu(idle_thread_array, x) = (p))
d7c53c9e
BP
90
91/*
92 * We need this for trampoline_base protection from concurrent accesses when
93 * off- and onlining cores wildly.
94 */
95static DEFINE_MUTEX(x86_cpu_hotplug_driver_mutex);
96
91d88ce2 97void cpu_hotplug_driver_lock(void)
d7c53c9e
BP
98{
99 mutex_lock(&x86_cpu_hotplug_driver_mutex);
100}
101
91d88ce2 102void cpu_hotplug_driver_unlock(void)
d7c53c9e
BP
103{
104 mutex_unlock(&x86_cpu_hotplug_driver_mutex);
105}
106
107ssize_t arch_cpu_probe(const char *buf, size_t count) { return -1; }
108ssize_t arch_cpu_release(const char *buf, size_t count) { return -1; }
cb3c8b90 109#else
f86c9985 110static struct task_struct *idle_thread_array[NR_CPUS] __cpuinitdata ;
cb3c8b90
GOC
111#define get_idle_for_cpu(x) (idle_thread_array[(x)])
112#define set_idle_for_cpu(x, p) (idle_thread_array[(x)] = (p))
113#endif
f6bc4029 114
a355352b
GC
115/* Number of siblings per CPU package */
116int smp_num_siblings = 1;
117EXPORT_SYMBOL(smp_num_siblings);
118
119/* Last level cache ID of each logical CPU */
120DEFINE_PER_CPU(u16, cpu_llc_id) = BAD_APICID;
121
a355352b 122/* representing HT siblings of each logical CPU */
7ad728f9 123DEFINE_PER_CPU(cpumask_var_t, cpu_sibling_map);
a355352b
GC
124EXPORT_PER_CPU_SYMBOL(cpu_sibling_map);
125
126/* representing HT and core siblings of each logical CPU */
7ad728f9 127DEFINE_PER_CPU(cpumask_var_t, cpu_core_map);
a355352b
GC
128EXPORT_PER_CPU_SYMBOL(cpu_core_map);
129
b3d7336d
YL
130DEFINE_PER_CPU(cpumask_var_t, cpu_llc_shared_map);
131
a355352b
GC
132/* Per CPU bogomips and other parameters */
133DEFINE_PER_CPU_SHARED_ALIGNED(struct cpuinfo_x86, cpu_info);
134EXPORT_PER_CPU_SYMBOL(cpu_info);
768d9505 135
2b6163bf 136atomic_t init_deasserted;
cb3c8b90 137
cb3c8b90
GOC
138/*
139 * Report back to the Boot Processor.
140 * Running on AP.
141 */
a4928cff 142static void __cpuinit smp_callin(void)
cb3c8b90
GOC
143{
144 int cpuid, phys_id;
145 unsigned long timeout;
146
147 /*
148 * If waken up by an INIT in an 82489DX configuration
149 * we may get here before an INIT-deassert IPI reaches
150 * our local APIC. We have to wait for the IPI or we'll
151 * lock up on an APIC access.
152 */
a9659366
IM
153 if (apic->wait_for_init_deassert)
154 apic->wait_for_init_deassert(&init_deasserted);
cb3c8b90
GOC
155
156 /*
157 * (This works even if the APIC is not enabled.)
158 */
4c9961d5 159 phys_id = read_apic_id();
cb3c8b90 160 cpuid = smp_processor_id();
c2d1cec1 161 if (cpumask_test_cpu(cpuid, cpu_callin_mask)) {
cb3c8b90
GOC
162 panic("%s: phys CPU#%d, CPU#%d already present??\n", __func__,
163 phys_id, cpuid);
164 }
cfc1b9a6 165 pr_debug("CPU#%d (phys ID: %d) waiting for CALLOUT\n", cpuid, phys_id);
cb3c8b90
GOC
166
167 /*
168 * STARTUP IPIs are fragile beasts as they might sometimes
169 * trigger some glue motherboard logic. Complete APIC bus
170 * silence for 1 second, this overestimates the time the
171 * boot CPU is spending to send the up to 2 STARTUP IPIs
172 * by a factor of two. This should be enough.
173 */
174
175 /*
176 * Waiting 2s total for startup (udelay is not yet working)
177 */
178 timeout = jiffies + 2*HZ;
179 while (time_before(jiffies, timeout)) {
180 /*
181 * Has the boot CPU finished it's STARTUP sequence?
182 */
c2d1cec1 183 if (cpumask_test_cpu(cpuid, cpu_callout_mask))
cb3c8b90
GOC
184 break;
185 cpu_relax();
186 }
187
188 if (!time_before(jiffies, timeout)) {
189 panic("%s: CPU%d started up but did not get a callout!\n",
190 __func__, cpuid);
191 }
192
193 /*
194 * the boot CPU has finished the init stage and is spinning
195 * on callin_map until we finish. We are free to set up this
196 * CPU, first the APIC. (this is probably redundant on most
197 * boards)
198 */
199
cfc1b9a6 200 pr_debug("CALLIN, before setup_local_APIC().\n");
333344d9
IM
201 if (apic->smp_callin_clear_local_apic)
202 apic->smp_callin_clear_local_apic();
cb3c8b90
GOC
203 setup_local_APIC();
204 end_local_APIC_setup();
cb3c8b90 205
9d133e5d
SS
206 /*
207 * Need to setup vector mappings before we enable interrupts.
208 */
36e9e1ea 209 setup_vector_irq(smp_processor_id());
b565201c
JS
210
211 /*
212 * Save our processor parameters. Note: this information
213 * is needed for clock calibration.
214 */
215 smp_store_cpu_info(cpuid);
216
cb3c8b90
GOC
217 /*
218 * Get our bogomips.
b565201c
JS
219 * Update loops_per_jiffy in cpu_data. Previous call to
220 * smp_store_cpu_info() stored a value that is close but not as
221 * accurate as the value just calculated.
cb3c8b90
GOC
222 *
223 * Need to enable IRQs because it can take longer and then
224 * the NMI watchdog might kill us.
225 */
226 local_irq_enable();
227 calibrate_delay();
b565201c 228 cpu_data(cpuid).loops_per_jiffy = loops_per_jiffy;
cb3c8b90 229 local_irq_disable();
cfc1b9a6 230 pr_debug("Stack at about %p\n", &cpuid);
cb3c8b90 231
5ef428c4
AK
232 /*
233 * This must be done before setting cpu_online_mask
234 * or calling notify_cpu_starting.
235 */
236 set_cpu_sibling_map(raw_smp_processor_id());
237 wmb();
238
85257024
PZ
239 notify_cpu_starting(cpuid);
240
cb3c8b90
GOC
241 /*
242 * Allow the master to continue.
243 */
c2d1cec1 244 cpumask_set_cpu(cpuid, cpu_callin_mask);
cb3c8b90
GOC
245}
246
bbc2ff6a
GOC
247/*
248 * Activate a secondary processor.
249 */
0ca59dd9 250notrace static void __cpuinit start_secondary(void *unused)
bbc2ff6a
GOC
251{
252 /*
253 * Don't put *anything* before cpu_init(), SMP booting is too
254 * fragile that we want to limit the things done here to the
255 * most necessary things.
256 */
b40827fa
BP
257 cpu_init();
258 preempt_disable();
259 smp_callin();
fd89a137
JR
260
261#ifdef CONFIG_X86_32
b40827fa 262 /* switch away from the initial page table */
fd89a137
JR
263 load_cr3(swapper_pg_dir);
264 __flush_tlb_all();
265#endif
266
bbc2ff6a
GOC
267 /* otherwise gcc will move up smp_processor_id before the cpu_init */
268 barrier();
269 /*
270 * Check TSC synchronization with the BP:
271 */
272 check_tsc_sync_target();
273
bbc2ff6a
GOC
274 /*
275 * We need to hold call_lock, so there is no inconsistency
276 * between the time smp_call_function() determines number of
277 * IPI recipients, and the time when the determination is made
278 * for which cpus receive the IPI. Holding this
279 * lock helps us to not include this cpu in a currently in progress
280 * smp_call_function().
d388e5fd
EB
281 *
282 * We need to hold vector_lock so there the set of online cpus
283 * does not change while we are assigning vectors to cpus. Holding
284 * this lock ensures we don't half assign or remove an irq from a cpu.
bbc2ff6a 285 */
0cefa5b9 286 ipi_call_lock();
d388e5fd 287 lock_vector_lock();
c2d1cec1 288 set_cpu_online(smp_processor_id(), true);
d388e5fd 289 unlock_vector_lock();
0cefa5b9 290 ipi_call_unlock();
bbc2ff6a 291 per_cpu(cpu_state, smp_processor_id()) = CPU_ONLINE;
78c06176 292 x86_platform.nmi_init();
bbc2ff6a 293
fd8a7de1
TG
294 /*
295 * Wait until the cpu which brought this one up marked it
296 * online before enabling interrupts. If we don't do that then
297 * we can end up waking up the softirq thread before this cpu
298 * reached the active state, which makes the scheduler unhappy
299 * and schedule the softirq thread on the wrong cpu. This is
300 * only observable with forced threaded interrupts, but in
301 * theory it could also happen w/o them. It's just way harder
302 * to achieve.
303 */
304 while (!cpumask_test_cpu(smp_processor_id(), cpu_active_mask))
305 cpu_relax();
306
0cefa5b9
MS
307 /* enable local interrupts */
308 local_irq_enable();
309
35f720c5
JP
310 /* to prevent fake stack check failure in clock setup */
311 boot_init_stack_canary();
0cefa5b9 312
736decac 313 x86_cpuinit.setup_percpu_clockev();
bbc2ff6a
GOC
314
315 wmb();
316 cpu_idle();
317}
318
1d89a7f0
GOC
319/*
320 * The bootstrap kernel entry code has set these up. Save them for
321 * a given CPU
322 */
323
324void __cpuinit smp_store_cpu_info(int id)
325{
326 struct cpuinfo_x86 *c = &cpu_data(id);
327
b3d7336d 328 *c = boot_cpu_data;
1d89a7f0
GOC
329 c->cpu_index = id;
330 if (id != 0)
331 identify_secondary_cpu(c);
1d89a7f0
GOC
332}
333
d4fbe4f0
AH
334static void __cpuinit link_thread_siblings(int cpu1, int cpu2)
335{
d4fbe4f0
AH
336 cpumask_set_cpu(cpu1, cpu_sibling_mask(cpu2));
337 cpumask_set_cpu(cpu2, cpu_sibling_mask(cpu1));
338 cpumask_set_cpu(cpu1, cpu_core_mask(cpu2));
339 cpumask_set_cpu(cpu2, cpu_core_mask(cpu1));
b3d7336d
YL
340 cpumask_set_cpu(cpu1, cpu_llc_shared_mask(cpu2));
341 cpumask_set_cpu(cpu2, cpu_llc_shared_mask(cpu1));
d4fbe4f0
AH
342}
343
1d89a7f0 344
768d9505
GC
345void __cpuinit set_cpu_sibling_map(int cpu)
346{
347 int i;
348 struct cpuinfo_x86 *c = &cpu_data(cpu);
349
c2d1cec1 350 cpumask_set_cpu(cpu, cpu_sibling_setup_mask);
768d9505
GC
351
352 if (smp_num_siblings > 1) {
c2d1cec1
MT
353 for_each_cpu(i, cpu_sibling_setup_mask) {
354 struct cpuinfo_x86 *o = &cpu_data(i);
355
d4fbe4f0
AH
356 if (cpu_has(c, X86_FEATURE_TOPOEXT)) {
357 if (c->phys_proc_id == o->phys_proc_id &&
d518573d 358 per_cpu(cpu_llc_id, cpu) == per_cpu(cpu_llc_id, i) &&
d4fbe4f0
AH
359 c->compute_unit_id == o->compute_unit_id)
360 link_thread_siblings(cpu, i);
361 } else if (c->phys_proc_id == o->phys_proc_id &&
362 c->cpu_core_id == o->cpu_core_id) {
363 link_thread_siblings(cpu, i);
768d9505
GC
364 }
365 }
366 } else {
c2d1cec1 367 cpumask_set_cpu(cpu, cpu_sibling_mask(cpu));
768d9505
GC
368 }
369
b3d7336d 370 cpumask_set_cpu(cpu, cpu_llc_shared_mask(cpu));
768d9505 371
7b543a53 372 if (__this_cpu_read(cpu_info.x86_max_cores) == 1) {
c2d1cec1 373 cpumask_copy(cpu_core_mask(cpu), cpu_sibling_mask(cpu));
768d9505
GC
374 c->booted_cores = 1;
375 return;
376 }
377
c2d1cec1 378 for_each_cpu(i, cpu_sibling_setup_mask) {
768d9505
GC
379 if (per_cpu(cpu_llc_id, cpu) != BAD_APICID &&
380 per_cpu(cpu_llc_id, cpu) == per_cpu(cpu_llc_id, i)) {
b3d7336d
YL
381 cpumask_set_cpu(i, cpu_llc_shared_mask(cpu));
382 cpumask_set_cpu(cpu, cpu_llc_shared_mask(i));
768d9505
GC
383 }
384 if (c->phys_proc_id == cpu_data(i).phys_proc_id) {
c2d1cec1
MT
385 cpumask_set_cpu(i, cpu_core_mask(cpu));
386 cpumask_set_cpu(cpu, cpu_core_mask(i));
768d9505
GC
387 /*
388 * Does this new cpu bringup a new core?
389 */
c2d1cec1 390 if (cpumask_weight(cpu_sibling_mask(cpu)) == 1) {
768d9505
GC
391 /*
392 * for each core in package, increment
393 * the booted_cores for this new cpu
394 */
c2d1cec1 395 if (cpumask_first(cpu_sibling_mask(i)) == i)
768d9505
GC
396 c->booted_cores++;
397 /*
398 * increment the core count for all
399 * the other cpus in this package
400 */
401 if (i != cpu)
402 cpu_data(i).booted_cores++;
403 } else if (i != cpu && !c->booted_cores)
404 c->booted_cores = cpu_data(i).booted_cores;
405 }
406 }
407}
408
70708a18 409/* maps the cpu to the sched domain representing multi-core */
030bb203 410const struct cpumask *cpu_coregroup_mask(int cpu)
70708a18
GC
411{
412 struct cpuinfo_x86 *c = &cpu_data(cpu);
413 /*
414 * For perf, we return last level cache shared map.
415 * And for power savings, we return cpu_core_map
416 */
5a925b42
AH
417 if ((sched_mc_power_savings || sched_smt_power_savings) &&
418 !(cpu_has(c, X86_FEATURE_AMD_DCM)))
c2d1cec1 419 return cpu_core_mask(cpu);
70708a18 420 else
b3d7336d 421 return cpu_llc_shared_mask(cpu);
030bb203
RR
422}
423
a4928cff 424static void impress_friends(void)
904541e2
GOC
425{
426 int cpu;
427 unsigned long bogosum = 0;
428 /*
429 * Allow the user to impress friends.
430 */
cfc1b9a6 431 pr_debug("Before bogomips.\n");
904541e2 432 for_each_possible_cpu(cpu)
c2d1cec1 433 if (cpumask_test_cpu(cpu, cpu_callout_mask))
904541e2
GOC
434 bogosum += cpu_data(cpu).loops_per_jiffy;
435 printk(KERN_INFO
436 "Total of %d processors activated (%lu.%02lu BogoMIPS).\n",
f68e00a3 437 num_online_cpus(),
904541e2
GOC
438 bogosum/(500000/HZ),
439 (bogosum/(5000/HZ))%100);
440
cfc1b9a6 441 pr_debug("Before bogocount - setting activated=1.\n");
904541e2
GOC
442}
443
569712b2 444void __inquire_remote_apic(int apicid)
cb3c8b90
GOC
445{
446 unsigned i, regs[] = { APIC_ID >> 4, APIC_LVR >> 4, APIC_SPIV >> 4 };
a6c23905 447 const char * const names[] = { "ID", "VERSION", "SPIV" };
cb3c8b90
GOC
448 int timeout;
449 u32 status;
450
823b259b 451 printk(KERN_INFO "Inquiring remote APIC 0x%x...\n", apicid);
cb3c8b90
GOC
452
453 for (i = 0; i < ARRAY_SIZE(regs); i++) {
823b259b 454 printk(KERN_INFO "... APIC 0x%x %s: ", apicid, names[i]);
cb3c8b90
GOC
455
456 /*
457 * Wait for idle.
458 */
459 status = safe_apic_wait_icr_idle();
460 if (status)
461 printk(KERN_CONT
462 "a previous APIC delivery may have failed\n");
463
1b374e4d 464 apic_icr_write(APIC_DM_REMRD | regs[i], apicid);
cb3c8b90
GOC
465
466 timeout = 0;
467 do {
468 udelay(100);
469 status = apic_read(APIC_ICR) & APIC_ICR_RR_MASK;
470 } while (status == APIC_ICR_RR_INPROG && timeout++ < 1000);
471
472 switch (status) {
473 case APIC_ICR_RR_VALID:
474 status = apic_read(APIC_RRR);
475 printk(KERN_CONT "%08x\n", status);
476 break;
477 default:
478 printk(KERN_CONT "failed\n");
479 }
480 }
481}
482
cb3c8b90
GOC
483/*
484 * Poke the other CPU in the eye via NMI to wake it up. Remember that the normal
485 * INIT, INIT, STARTUP sequence will reset the chip hard for us, and this
486 * won't ... remember to clear down the APIC, etc later.
487 */
cece3155 488int __cpuinit
569712b2 489wakeup_secondary_cpu_via_nmi(int logical_apicid, unsigned long start_eip)
cb3c8b90
GOC
490{
491 unsigned long send_status, accept_status = 0;
492 int maxlvt;
493
494 /* Target chip */
cb3c8b90
GOC
495 /* Boot on the stack */
496 /* Kick the second */
bdb1a9b6 497 apic_icr_write(APIC_DM_NMI | apic->dest_logical, logical_apicid);
cb3c8b90 498
cfc1b9a6 499 pr_debug("Waiting for send to finish...\n");
cb3c8b90
GOC
500 send_status = safe_apic_wait_icr_idle();
501
502 /*
503 * Give the other CPU some time to accept the IPI.
504 */
505 udelay(200);
569712b2 506 if (APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid])) {
59ef48a5
CG
507 maxlvt = lapic_get_maxlvt();
508 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
509 apic_write(APIC_ESR, 0);
510 accept_status = (apic_read(APIC_ESR) & 0xEF);
511 }
cfc1b9a6 512 pr_debug("NMI sent.\n");
cb3c8b90
GOC
513
514 if (send_status)
515 printk(KERN_ERR "APIC never delivered???\n");
516 if (accept_status)
517 printk(KERN_ERR "APIC delivery error (%lx).\n", accept_status);
518
519 return (send_status | accept_status);
520}
cb3c8b90 521
cece3155 522static int __cpuinit
569712b2 523wakeup_secondary_cpu_via_init(int phys_apicid, unsigned long start_eip)
cb3c8b90
GOC
524{
525 unsigned long send_status, accept_status = 0;
526 int maxlvt, num_starts, j;
527
593f4a78
MR
528 maxlvt = lapic_get_maxlvt();
529
cb3c8b90
GOC
530 /*
531 * Be paranoid about clearing APIC errors.
532 */
533 if (APIC_INTEGRATED(apic_version[phys_apicid])) {
593f4a78
MR
534 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
535 apic_write(APIC_ESR, 0);
cb3c8b90
GOC
536 apic_read(APIC_ESR);
537 }
538
cfc1b9a6 539 pr_debug("Asserting INIT.\n");
cb3c8b90
GOC
540
541 /*
542 * Turn INIT on target chip
543 */
cb3c8b90
GOC
544 /*
545 * Send IPI
546 */
1b374e4d
SS
547 apic_icr_write(APIC_INT_LEVELTRIG | APIC_INT_ASSERT | APIC_DM_INIT,
548 phys_apicid);
cb3c8b90 549
cfc1b9a6 550 pr_debug("Waiting for send to finish...\n");
cb3c8b90
GOC
551 send_status = safe_apic_wait_icr_idle();
552
553 mdelay(10);
554
cfc1b9a6 555 pr_debug("Deasserting INIT.\n");
cb3c8b90
GOC
556
557 /* Target chip */
cb3c8b90 558 /* Send IPI */
1b374e4d 559 apic_icr_write(APIC_INT_LEVELTRIG | APIC_DM_INIT, phys_apicid);
cb3c8b90 560
cfc1b9a6 561 pr_debug("Waiting for send to finish...\n");
cb3c8b90
GOC
562 send_status = safe_apic_wait_icr_idle();
563
564 mb();
565 atomic_set(&init_deasserted, 1);
566
567 /*
568 * Should we send STARTUP IPIs ?
569 *
570 * Determine this based on the APIC version.
571 * If we don't have an integrated APIC, don't send the STARTUP IPIs.
572 */
573 if (APIC_INTEGRATED(apic_version[phys_apicid]))
574 num_starts = 2;
575 else
576 num_starts = 0;
577
578 /*
579 * Paravirt / VMI wants a startup IPI hook here to set up the
580 * target processor state.
581 */
582 startup_ipi_hook(phys_apicid, (unsigned long) start_secondary,
11d4c3f9 583 stack_start);
cb3c8b90
GOC
584
585 /*
586 * Run STARTUP IPI loop.
587 */
cfc1b9a6 588 pr_debug("#startup loops: %d.\n", num_starts);
cb3c8b90 589
cb3c8b90 590 for (j = 1; j <= num_starts; j++) {
cfc1b9a6 591 pr_debug("Sending STARTUP #%d.\n", j);
593f4a78
MR
592 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
593 apic_write(APIC_ESR, 0);
cb3c8b90 594 apic_read(APIC_ESR);
cfc1b9a6 595 pr_debug("After apic_write.\n");
cb3c8b90
GOC
596
597 /*
598 * STARTUP IPI
599 */
600
601 /* Target chip */
cb3c8b90
GOC
602 /* Boot on the stack */
603 /* Kick the second */
1b374e4d
SS
604 apic_icr_write(APIC_DM_STARTUP | (start_eip >> 12),
605 phys_apicid);
cb3c8b90
GOC
606
607 /*
608 * Give the other CPU some time to accept the IPI.
609 */
610 udelay(300);
611
cfc1b9a6 612 pr_debug("Startup point 1.\n");
cb3c8b90 613
cfc1b9a6 614 pr_debug("Waiting for send to finish...\n");
cb3c8b90
GOC
615 send_status = safe_apic_wait_icr_idle();
616
617 /*
618 * Give the other CPU some time to accept the IPI.
619 */
620 udelay(200);
593f4a78 621 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
cb3c8b90 622 apic_write(APIC_ESR, 0);
cb3c8b90
GOC
623 accept_status = (apic_read(APIC_ESR) & 0xEF);
624 if (send_status || accept_status)
625 break;
626 }
cfc1b9a6 627 pr_debug("After Startup.\n");
cb3c8b90
GOC
628
629 if (send_status)
630 printk(KERN_ERR "APIC never delivered???\n");
631 if (accept_status)
632 printk(KERN_ERR "APIC delivery error (%lx).\n", accept_status);
633
634 return (send_status | accept_status);
635}
cb3c8b90
GOC
636
637struct create_idle {
638 struct work_struct work;
639 struct task_struct *idle;
640 struct completion done;
641 int cpu;
642};
643
644static void __cpuinit do_fork_idle(struct work_struct *work)
645{
646 struct create_idle *c_idle =
647 container_of(work, struct create_idle, work);
648
649 c_idle->idle = fork_idle(c_idle->cpu);
650 complete(&c_idle->done);
651}
652
2eaad1fd
MT
653/* reduce the number of lines printed when booting a large cpu count system */
654static void __cpuinit announce_cpu(int cpu, int apicid)
655{
656 static int current_node = -1;
4adc8b71 657 int node = early_cpu_to_node(cpu);
2eaad1fd
MT
658
659 if (system_state == SYSTEM_BOOTING) {
660 if (node != current_node) {
661 if (current_node > (-1))
662 pr_cont(" Ok.\n");
663 current_node = node;
664 pr_info("Booting Node %3d, Processors ", node);
665 }
666 pr_cont(" #%d%s", cpu, cpu == (nr_cpu_ids - 1) ? " Ok.\n" : "");
667 return;
668 } else
669 pr_info("Booting Node %d Processor %d APIC 0x%x\n",
670 node, cpu, apicid);
671}
672
cb3c8b90
GOC
673/*
674 * NOTE - on most systems this is a PHYSICAL apic ID, but on multiquad
675 * (ie clustered apic addressing mode), this is a LOGICAL apic ID.
1f5bcabf
IM
676 * Returns zero if CPU booted OK, else error code from
677 * ->wakeup_secondary_cpu.
cb3c8b90 678 */
ab6fb7c0 679static int __cpuinit do_boot_cpu(int apicid, int cpu)
cb3c8b90
GOC
680{
681 unsigned long boot_error = 0;
cb3c8b90 682 unsigned long start_ip;
ab6fb7c0 683 int timeout;
cb3c8b90 684 struct create_idle c_idle = {
ab6fb7c0
IM
685 .cpu = cpu,
686 .done = COMPLETION_INITIALIZER_ONSTACK(c_idle.done),
cb3c8b90 687 };
ab6fb7c0 688
ca1cab37 689 INIT_WORK_ONSTACK(&c_idle.work, do_fork_idle);
cb3c8b90 690
cb3c8b90
GOC
691 alternatives_smp_switch(1);
692
693 c_idle.idle = get_idle_for_cpu(cpu);
694
695 /*
696 * We can't use kernel_thread since we must avoid to
697 * reschedule the child.
698 */
699 if (c_idle.idle) {
700 c_idle.idle->thread.sp = (unsigned long) (((struct pt_regs *)
701 (THREAD_SIZE + task_stack_page(c_idle.idle))) - 1);
702 init_idle(c_idle.idle, cpu);
703 goto do_rest;
704 }
705
d7a7c573
SS
706 schedule_work(&c_idle.work);
707 wait_for_completion(&c_idle.done);
cb3c8b90
GOC
708
709 if (IS_ERR(c_idle.idle)) {
710 printk("failed fork for CPU %d\n", cpu);
dc186ad7 711 destroy_work_on_stack(&c_idle.work);
cb3c8b90
GOC
712 return PTR_ERR(c_idle.idle);
713 }
714
715 set_idle_for_cpu(cpu, c_idle.idle);
716do_rest:
cb3c8b90 717 per_cpu(current_task, cpu) = c_idle.idle;
c6f5e0ac 718#ifdef CONFIG_X86_32
cb3c8b90 719 /* Stack for startup_32 can be just as for start_secondary onwards */
cb3c8b90
GOC
720 irq_ctx_init(cpu);
721#else
cb3c8b90 722 clear_tsk_thread_flag(c_idle.idle, TIF_FORK);
004aa322 723 initial_gs = per_cpu_offset(cpu);
9af45651
BG
724 per_cpu(kernel_stack, cpu) =
725 (unsigned long)task_stack_page(c_idle.idle) -
726 KERNEL_STACK_OFFSET + THREAD_SIZE;
cb3c8b90 727#endif
a939098a 728 early_gdt_descr.address = (unsigned long)get_cpu_gdt_table(cpu);
3e970473 729 initial_code = (unsigned long)start_secondary;
11d4c3f9 730 stack_start = c_idle.idle->thread.sp;
cb3c8b90
GOC
731
732 /* start_ip had better be page-aligned! */
4822b7fc 733 start_ip = trampoline_address();
cb3c8b90 734
2eaad1fd
MT
735 /* So we see what's up */
736 announce_cpu(cpu, apicid);
cb3c8b90
GOC
737
738 /*
739 * This grunge runs the startup process for
740 * the targeted processor.
741 */
742
4822b7fc
PA
743 printk(KERN_DEBUG "smpboot cpu %d: start_ip = %lx\n", cpu, start_ip);
744
cb3c8b90
GOC
745 atomic_set(&init_deasserted, 0);
746
34d05591 747 if (get_uv_system_type() != UV_NON_UNIQUE_APIC) {
cb3c8b90 748
cfc1b9a6 749 pr_debug("Setting warm reset code and vector.\n");
cb3c8b90 750
34d05591
JS
751 smpboot_setup_warm_reset_vector(start_ip);
752 /*
753 * Be paranoid about clearing APIC errors.
db96b0a0
CG
754 */
755 if (APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid])) {
756 apic_write(APIC_ESR, 0);
757 apic_read(APIC_ESR);
758 }
34d05591 759 }
cb3c8b90 760
cb3c8b90 761 /*
1f5bcabf
IM
762 * Kick the secondary CPU. Use the method in the APIC driver
763 * if it's defined - or use an INIT boot APIC message otherwise:
cb3c8b90 764 */
1f5bcabf
IM
765 if (apic->wakeup_secondary_cpu)
766 boot_error = apic->wakeup_secondary_cpu(apicid, start_ip);
767 else
768 boot_error = wakeup_secondary_cpu_via_init(apicid, start_ip);
cb3c8b90
GOC
769
770 if (!boot_error) {
771 /*
772 * allow APs to start initializing.
773 */
cfc1b9a6 774 pr_debug("Before Callout %d.\n", cpu);
c2d1cec1 775 cpumask_set_cpu(cpu, cpu_callout_mask);
cfc1b9a6 776 pr_debug("After Callout %d.\n", cpu);
cb3c8b90
GOC
777
778 /*
779 * Wait 5s total for a response
780 */
781 for (timeout = 0; timeout < 50000; timeout++) {
c2d1cec1 782 if (cpumask_test_cpu(cpu, cpu_callin_mask))
cb3c8b90
GOC
783 break; /* It has booted */
784 udelay(100);
68f202e4
SS
785 /*
786 * Allow other tasks to run while we wait for the
787 * AP to come online. This also gives a chance
788 * for the MTRR work(triggered by the AP coming online)
789 * to be completed in the stop machine context.
790 */
791 schedule();
cb3c8b90
GOC
792 }
793
21c3fcf3
YL
794 if (cpumask_test_cpu(cpu, cpu_callin_mask)) {
795 print_cpu_msr(&cpu_data(cpu));
2eaad1fd 796 pr_debug("CPU%d: has booted.\n", cpu);
21c3fcf3 797 } else {
cb3c8b90 798 boot_error = 1;
4822b7fc
PA
799 if (*(volatile u32 *)TRAMPOLINE_SYM(trampoline_status)
800 == 0xA5A5A5A5)
cb3c8b90 801 /* trampoline started but...? */
2eaad1fd 802 pr_err("CPU%d: Stuck ??\n", cpu);
cb3c8b90
GOC
803 else
804 /* trampoline code not run */
2eaad1fd 805 pr_err("CPU%d: Not responding.\n", cpu);
25dc0049
IM
806 if (apic->inquire_remote_apic)
807 apic->inquire_remote_apic(apicid);
cb3c8b90
GOC
808 }
809 }
1a51e3a0 810
cb3c8b90
GOC
811 if (boot_error) {
812 /* Try to put things back the way they were before ... */
23ca4bba 813 numa_remove_cpu(cpu); /* was set by numa_add_cpu */
c2d1cec1
MT
814
815 /* was set by do_boot_cpu() */
816 cpumask_clear_cpu(cpu, cpu_callout_mask);
817
818 /* was set by cpu_init() */
819 cpumask_clear_cpu(cpu, cpu_initialized_mask);
820
821 set_cpu_present(cpu, false);
cb3c8b90
GOC
822 per_cpu(x86_cpu_to_apicid, cpu) = BAD_APICID;
823 }
824
825 /* mark "stuck" area as not stuck */
4822b7fc 826 *(volatile u32 *)TRAMPOLINE_SYM(trampoline_status) = 0;
cb3c8b90 827
02421f98
YL
828 if (get_uv_system_type() != UV_NON_UNIQUE_APIC) {
829 /*
830 * Cleanup possible dangling ends...
831 */
832 smpboot_restore_warm_reset_vector();
833 }
63d38198 834
dc186ad7 835 destroy_work_on_stack(&c_idle.work);
cb3c8b90
GOC
836 return boot_error;
837}
838
839int __cpuinit native_cpu_up(unsigned int cpu)
840{
a21769a4 841 int apicid = apic->cpu_present_to_apicid(cpu);
cb3c8b90
GOC
842 unsigned long flags;
843 int err;
844
845 WARN_ON(irqs_disabled());
846
cfc1b9a6 847 pr_debug("++++++++++++++++++++=_---CPU UP %u\n", cpu);
cb3c8b90
GOC
848
849 if (apicid == BAD_APICID || apicid == boot_cpu_physical_apicid ||
c284b42a
SS
850 !physid_isset(apicid, phys_cpu_present_map) ||
851 (!x2apic_mode && apicid >= 255)) {
cb3c8b90
GOC
852 printk(KERN_ERR "%s: bad cpu %d\n", __func__, cpu);
853 return -EINVAL;
854 }
855
856 /*
857 * Already booted CPU?
858 */
c2d1cec1 859 if (cpumask_test_cpu(cpu, cpu_callin_mask)) {
cfc1b9a6 860 pr_debug("do_boot_cpu %d Already started\n", cpu);
cb3c8b90
GOC
861 return -ENOSYS;
862 }
863
864 /*
865 * Save current MTRR state in case it was changed since early boot
866 * (e.g. by the ACPI SMI) to initialize new CPUs with MTRRs in sync:
867 */
868 mtrr_save_state();
869
870 per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
871
cb3c8b90 872 err = do_boot_cpu(apicid, cpu);
61165d7a 873 if (err) {
cfc1b9a6 874 pr_debug("do_boot_cpu failed %d\n", err);
61165d7a 875 return -EIO;
cb3c8b90
GOC
876 }
877
878 /*
879 * Check TSC synchronization with the AP (keep irqs disabled
880 * while doing so):
881 */
882 local_irq_save(flags);
883 check_tsc_sync_source(cpu);
884 local_irq_restore(flags);
885
7c04e64a 886 while (!cpu_online(cpu)) {
cb3c8b90
GOC
887 cpu_relax();
888 touch_nmi_watchdog();
889 }
890
891 return 0;
892}
893
7167d08e
HK
894/**
895 * arch_disable_smp_support() - disables SMP support for x86 at runtime
896 */
897void arch_disable_smp_support(void)
898{
899 disable_ioapic_support();
900}
901
8aef135c
GOC
902/*
903 * Fall back to non SMP mode after errors.
904 *
905 * RED-PEN audit/test this more. I bet there is more state messed up here.
906 */
907static __init void disable_smp(void)
908{
4f062896
RR
909 init_cpu_present(cpumask_of(0));
910 init_cpu_possible(cpumask_of(0));
8aef135c 911 smpboot_clear_io_apic_irqs();
0f385d1d 912
8aef135c 913 if (smp_found_config)
b6df1b8b 914 physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map);
8aef135c 915 else
b6df1b8b 916 physid_set_mask_of_physid(0, &phys_cpu_present_map);
c2d1cec1
MT
917 cpumask_set_cpu(0, cpu_sibling_mask(0));
918 cpumask_set_cpu(0, cpu_core_mask(0));
8aef135c
GOC
919}
920
921/*
922 * Various sanity checks.
923 */
924static int __init smp_sanity_check(unsigned max_cpus)
925{
ac23d4ee 926 preempt_disable();
a58f03b0 927
1ff2f20d 928#if !defined(CONFIG_X86_BIGSMP) && defined(CONFIG_X86_32)
a58f03b0
YL
929 if (def_to_bigsmp && nr_cpu_ids > 8) {
930 unsigned int cpu;
931 unsigned nr;
932
933 printk(KERN_WARNING
934 "More than 8 CPUs detected - skipping them.\n"
26f7ef14 935 "Use CONFIG_X86_BIGSMP.\n");
a58f03b0
YL
936
937 nr = 0;
938 for_each_present_cpu(cpu) {
939 if (nr >= 8)
c2d1cec1 940 set_cpu_present(cpu, false);
a58f03b0
YL
941 nr++;
942 }
943
944 nr = 0;
945 for_each_possible_cpu(cpu) {
946 if (nr >= 8)
c2d1cec1 947 set_cpu_possible(cpu, false);
a58f03b0
YL
948 nr++;
949 }
950
951 nr_cpu_ids = 8;
952 }
953#endif
954
8aef135c 955 if (!physid_isset(hard_smp_processor_id(), phys_cpu_present_map)) {
55c395b4
MT
956 printk(KERN_WARNING
957 "weird, boot CPU (#%d) not listed by the BIOS.\n",
958 hard_smp_processor_id());
959
8aef135c
GOC
960 physid_set(hard_smp_processor_id(), phys_cpu_present_map);
961 }
962
963 /*
964 * If we couldn't find an SMP configuration at boot time,
965 * get out of here now!
966 */
967 if (!smp_found_config && !acpi_lapic) {
ac23d4ee 968 preempt_enable();
8aef135c
GOC
969 printk(KERN_NOTICE "SMP motherboard not detected.\n");
970 disable_smp();
971 if (APIC_init_uniprocessor())
972 printk(KERN_NOTICE "Local APIC not detected."
973 " Using dummy APIC emulation.\n");
974 return -1;
975 }
976
977 /*
978 * Should not be necessary because the MP table should list the boot
979 * CPU too, but we do it for the sake of robustness anyway.
980 */
a27a6210 981 if (!apic->check_phys_apicid_present(boot_cpu_physical_apicid)) {
8aef135c
GOC
982 printk(KERN_NOTICE
983 "weird, boot CPU (#%d) not listed by the BIOS.\n",
984 boot_cpu_physical_apicid);
985 physid_set(hard_smp_processor_id(), phys_cpu_present_map);
986 }
ac23d4ee 987 preempt_enable();
8aef135c
GOC
988
989 /*
990 * If we couldn't find a local APIC, then get out of here now!
991 */
992 if (APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid]) &&
993 !cpu_has_apic) {
103428e5
CG
994 if (!disable_apic) {
995 pr_err("BIOS bug, local APIC #%d not detected!...\n",
996 boot_cpu_physical_apicid);
997 pr_err("... forcing use of dummy APIC emulation."
8aef135c 998 "(tell your hw vendor)\n");
103428e5 999 }
8aef135c 1000 smpboot_clear_io_apic();
7167d08e 1001 disable_ioapic_support();
8aef135c
GOC
1002 return -1;
1003 }
1004
1005 verify_local_APIC();
1006
1007 /*
1008 * If SMP should be disabled, then really disable it!
1009 */
1010 if (!max_cpus) {
73d08e63 1011 printk(KERN_INFO "SMP mode deactivated.\n");
8aef135c 1012 smpboot_clear_io_apic();
d54db1ac 1013
e90955c2 1014 connect_bsp_APIC();
e90955c2 1015 setup_local_APIC();
2fb270f3 1016 bsp_end_local_APIC_setup();
8aef135c
GOC
1017 return -1;
1018 }
1019
1020 return 0;
1021}
1022
1023static void __init smp_cpu_index_default(void)
1024{
1025 int i;
1026 struct cpuinfo_x86 *c;
1027
7c04e64a 1028 for_each_possible_cpu(i) {
8aef135c
GOC
1029 c = &cpu_data(i);
1030 /* mark all to hotplug */
9628937d 1031 c->cpu_index = nr_cpu_ids;
8aef135c
GOC
1032 }
1033}
1034
1035/*
1036 * Prepare for SMP bootup. The MP table or ACPI has been read
1037 * earlier. Just do some sanity checking here and enable APIC mode.
1038 */
1039void __init native_smp_prepare_cpus(unsigned int max_cpus)
1040{
7ad728f9
RR
1041 unsigned int i;
1042
deef3250 1043 preempt_disable();
8aef135c 1044 smp_cpu_index_default();
792363d2 1045
8aef135c
GOC
1046 /*
1047 * Setup boot CPU information
1048 */
1049 smp_store_cpu_info(0); /* Final full version of the data */
792363d2
YL
1050 cpumask_copy(cpu_callin_mask, cpumask_of(0));
1051 mb();
bd22a2f1 1052
8aef135c 1053 current_thread_info()->cpu = 0; /* needed? */
7ad728f9 1054 for_each_possible_cpu(i) {
79f55997
LZ
1055 zalloc_cpumask_var(&per_cpu(cpu_sibling_map, i), GFP_KERNEL);
1056 zalloc_cpumask_var(&per_cpu(cpu_core_map, i), GFP_KERNEL);
b3d7336d 1057 zalloc_cpumask_var(&per_cpu(cpu_llc_shared_map, i), GFP_KERNEL);
7ad728f9 1058 }
8aef135c
GOC
1059 set_cpu_sibling_map(0);
1060
6e1cb38a 1061
8aef135c
GOC
1062 if (smp_sanity_check(max_cpus) < 0) {
1063 printk(KERN_INFO "SMP disabled\n");
1064 disable_smp();
deef3250 1065 goto out;
8aef135c
GOC
1066 }
1067
fa47f7e5
SS
1068 default_setup_apic_routing();
1069
ac23d4ee 1070 preempt_disable();
4c9961d5 1071 if (read_apic_id() != boot_cpu_physical_apicid) {
8aef135c 1072 panic("Boot APIC ID in local APIC unexpected (%d vs %d)",
4c9961d5 1073 read_apic_id(), boot_cpu_physical_apicid);
8aef135c
GOC
1074 /* Or can we switch back to PIC here? */
1075 }
ac23d4ee 1076 preempt_enable();
8aef135c 1077
8aef135c 1078 connect_bsp_APIC();
b5841765 1079
8aef135c
GOC
1080 /*
1081 * Switch from PIC to APIC mode.
1082 */
1083 setup_local_APIC();
1084
8aef135c
GOC
1085 /*
1086 * Enable IO APIC before setting up error vector
1087 */
1088 if (!skip_ioapic_setup && nr_ioapics)
1089 enable_IO_APIC();
88d0f550 1090
2fb270f3 1091 bsp_end_local_APIC_setup();
8aef135c 1092
d83093b5
IM
1093 if (apic->setup_portio_remap)
1094 apic->setup_portio_remap();
8aef135c
GOC
1095
1096 smpboot_setup_io_apic();
1097 /*
1098 * Set up local APIC timer on boot CPU.
1099 */
1100
1101 printk(KERN_INFO "CPU%d: ", 0);
1102 print_cpu_info(&cpu_data(0));
736decac 1103 x86_init.timers.setup_percpu_clockev();
c4bd1fda
MS
1104
1105 if (is_uv_system())
1106 uv_system_init();
d0af9eed
SS
1107
1108 set_mtrr_aps_delayed_init();
deef3250
IM
1109out:
1110 preempt_enable();
8aef135c 1111}
d0af9eed 1112
3fb82d56
SS
1113void arch_disable_nonboot_cpus_begin(void)
1114{
1115 /*
1116 * Avoid the smp alternatives switch during the disable_nonboot_cpus().
1117 * In the suspend path, we will be back in the SMP mode shortly anyways.
1118 */
1119 skip_smp_alternatives = true;
1120}
1121
1122void arch_disable_nonboot_cpus_end(void)
1123{
1124 skip_smp_alternatives = false;
1125}
1126
d0af9eed
SS
1127void arch_enable_nonboot_cpus_begin(void)
1128{
1129 set_mtrr_aps_delayed_init();
1130}
1131
1132void arch_enable_nonboot_cpus_end(void)
1133{
1134 mtrr_aps_init();
1135}
1136
a8db8453
GOC
1137/*
1138 * Early setup to make printk work.
1139 */
1140void __init native_smp_prepare_boot_cpu(void)
1141{
1142 int me = smp_processor_id();
552be871 1143 switch_to_new_gdt(me);
c2d1cec1
MT
1144 /* already set me in cpu_online_mask in boot_cpu_init() */
1145 cpumask_set_cpu(me, cpu_callout_mask);
a8db8453
GOC
1146 per_cpu(cpu_state, me) = CPU_ONLINE;
1147}
1148
83f7eb9c
GOC
1149void __init native_smp_cpus_done(unsigned int max_cpus)
1150{
cfc1b9a6 1151 pr_debug("Boot done.\n");
83f7eb9c 1152
99e8b9ca 1153 nmi_selftest();
83f7eb9c 1154 impress_friends();
83f7eb9c
GOC
1155#ifdef CONFIG_X86_IO_APIC
1156 setup_ioapic_dest();
1157#endif
d0af9eed 1158 mtrr_aps_init();
83f7eb9c
GOC
1159}
1160
3b11ce7f
MT
1161static int __initdata setup_possible_cpus = -1;
1162static int __init _setup_possible_cpus(char *str)
1163{
1164 get_option(&str, &setup_possible_cpus);
1165 return 0;
1166}
1167early_param("possible_cpus", _setup_possible_cpus);
1168
1169
68a1c3f8 1170/*
4f062896 1171 * cpu_possible_mask should be static, it cannot change as cpu's
68a1c3f8
GC
1172 * are onlined, or offlined. The reason is per-cpu data-structures
1173 * are allocated by some modules at init time, and dont expect to
1174 * do this dynamically on cpu arrival/departure.
4f062896 1175 * cpu_present_mask on the other hand can change dynamically.
68a1c3f8
GC
1176 * In case when cpu_hotplug is not compiled, then we resort to current
1177 * behaviour, which is cpu_possible == cpu_present.
1178 * - Ashok Raj
1179 *
1180 * Three ways to find out the number of additional hotplug CPUs:
1181 * - If the BIOS specified disabled CPUs in ACPI/mptables use that.
3b11ce7f 1182 * - The user can overwrite it with possible_cpus=NUM
68a1c3f8
GC
1183 * - Otherwise don't reserve additional CPUs.
1184 * We do this because additional CPUs waste a lot of memory.
1185 * -AK
1186 */
1187__init void prefill_possible_map(void)
1188{
cb48bb59 1189 int i, possible;
68a1c3f8 1190
329513a3
YL
1191 /* no processor from mptable or madt */
1192 if (!num_processors)
1193 num_processors = 1;
1194
5f2eb550
JB
1195 i = setup_max_cpus ?: 1;
1196 if (setup_possible_cpus == -1) {
1197 possible = num_processors;
1198#ifdef CONFIG_HOTPLUG_CPU
1199 if (setup_max_cpus)
1200 possible += disabled_cpus;
1201#else
1202 if (possible > i)
1203 possible = i;
1204#endif
1205 } else
3b11ce7f
MT
1206 possible = setup_possible_cpus;
1207
730cf272
MT
1208 total_cpus = max_t(int, possible, num_processors + disabled_cpus);
1209
2b633e3f
YL
1210 /* nr_cpu_ids could be reduced via nr_cpus= */
1211 if (possible > nr_cpu_ids) {
3b11ce7f
MT
1212 printk(KERN_WARNING
1213 "%d Processors exceeds NR_CPUS limit of %d\n",
2b633e3f
YL
1214 possible, nr_cpu_ids);
1215 possible = nr_cpu_ids;
3b11ce7f 1216 }
68a1c3f8 1217
5f2eb550
JB
1218#ifdef CONFIG_HOTPLUG_CPU
1219 if (!setup_max_cpus)
1220#endif
1221 if (possible > i) {
1222 printk(KERN_WARNING
1223 "%d Processors exceeds max_cpus limit of %u\n",
1224 possible, setup_max_cpus);
1225 possible = i;
1226 }
1227
68a1c3f8
GC
1228 printk(KERN_INFO "SMP: Allowing %d CPUs, %d hotplug CPUs\n",
1229 possible, max_t(int, possible - num_processors, 0));
1230
1231 for (i = 0; i < possible; i++)
c2d1cec1 1232 set_cpu_possible(i, true);
5f2eb550
JB
1233 for (; i < NR_CPUS; i++)
1234 set_cpu_possible(i, false);
3461b0af
MT
1235
1236 nr_cpu_ids = possible;
68a1c3f8 1237}
69c18c15 1238
14adf855
CE
1239#ifdef CONFIG_HOTPLUG_CPU
1240
1241static void remove_siblinginfo(int cpu)
1242{
1243 int sibling;
1244 struct cpuinfo_x86 *c = &cpu_data(cpu);
1245
c2d1cec1
MT
1246 for_each_cpu(sibling, cpu_core_mask(cpu)) {
1247 cpumask_clear_cpu(cpu, cpu_core_mask(sibling));
14adf855
CE
1248 /*/
1249 * last thread sibling in this cpu core going down
1250 */
c2d1cec1 1251 if (cpumask_weight(cpu_sibling_mask(cpu)) == 1)
14adf855
CE
1252 cpu_data(sibling).booted_cores--;
1253 }
1254
c2d1cec1
MT
1255 for_each_cpu(sibling, cpu_sibling_mask(cpu))
1256 cpumask_clear_cpu(cpu, cpu_sibling_mask(sibling));
1257 cpumask_clear(cpu_sibling_mask(cpu));
1258 cpumask_clear(cpu_core_mask(cpu));
14adf855
CE
1259 c->phys_proc_id = 0;
1260 c->cpu_core_id = 0;
c2d1cec1 1261 cpumask_clear_cpu(cpu, cpu_sibling_setup_mask);
14adf855
CE
1262}
1263
69c18c15
GC
1264static void __ref remove_cpu_from_maps(int cpu)
1265{
c2d1cec1
MT
1266 set_cpu_online(cpu, false);
1267 cpumask_clear_cpu(cpu, cpu_callout_mask);
1268 cpumask_clear_cpu(cpu, cpu_callin_mask);
69c18c15 1269 /* was set by cpu_init() */
c2d1cec1 1270 cpumask_clear_cpu(cpu, cpu_initialized_mask);
23ca4bba 1271 numa_remove_cpu(cpu);
69c18c15
GC
1272}
1273
8227dce7 1274void cpu_disable_common(void)
69c18c15
GC
1275{
1276 int cpu = smp_processor_id();
69c18c15 1277
69c18c15
GC
1278 remove_siblinginfo(cpu);
1279
1280 /* It's now safe to remove this processor from the online map */
d388e5fd 1281 lock_vector_lock();
69c18c15 1282 remove_cpu_from_maps(cpu);
d388e5fd 1283 unlock_vector_lock();
d7b381bb 1284 fixup_irqs();
8227dce7
AN
1285}
1286
1287int native_cpu_disable(void)
1288{
1289 int cpu = smp_processor_id();
1290
1291 /*
1292 * Perhaps use cpufreq to drop frequency, but that could go
1293 * into generic code.
1294 *
1295 * We won't take down the boot processor on i386 due to some
1296 * interrupts only being able to be serviced by the BSP.
1297 * Especially so if we're not using an IOAPIC -zwane
1298 */
1299 if (cpu == 0)
1300 return -EBUSY;
1301
8227dce7
AN
1302 clear_local_APIC();
1303
1304 cpu_disable_common();
69c18c15
GC
1305 return 0;
1306}
1307
93be71b6 1308void native_cpu_die(unsigned int cpu)
69c18c15
GC
1309{
1310 /* We don't do anything here: idle task is faking death itself. */
1311 unsigned int i;
1312
1313 for (i = 0; i < 10; i++) {
1314 /* They ack this in play_dead by setting CPU_DEAD */
1315 if (per_cpu(cpu_state, cpu) == CPU_DEAD) {
2eaad1fd
MT
1316 if (system_state == SYSTEM_RUNNING)
1317 pr_info("CPU %u is now offline\n", cpu);
1318
69c18c15
GC
1319 if (1 == num_online_cpus())
1320 alternatives_smp_switch(0);
1321 return;
1322 }
1323 msleep(100);
1324 }
2eaad1fd 1325 pr_err("CPU %u didn't die...\n", cpu);
69c18c15 1326}
a21f5d88
AN
1327
1328void play_dead_common(void)
1329{
1330 idle_task_exit();
1331 reset_lazy_tlbstate();
02c68a02 1332 amd_e400_remove_cpu(raw_smp_processor_id());
a21f5d88
AN
1333
1334 mb();
1335 /* Ack it */
0a3aee0d 1336 __this_cpu_write(cpu_state, CPU_DEAD);
a21f5d88
AN
1337
1338 /*
1339 * With physical CPU hotplug, we should halt the cpu
1340 */
1341 local_irq_disable();
1342}
1343
ea530692
PA
1344/*
1345 * We need to flush the caches before going to sleep, lest we have
1346 * dirty data in our caches when we come back up.
1347 */
1348static inline void mwait_play_dead(void)
1349{
1350 unsigned int eax, ebx, ecx, edx;
1351 unsigned int highest_cstate = 0;
1352 unsigned int highest_subcstate = 0;
1353 int i;
ce5f6824 1354 void *mwait_ptr;
93789b32 1355 struct cpuinfo_x86 *c = __this_cpu_ptr(&cpu_info);
ea530692 1356
4f3c125c 1357 if (!(this_cpu_has(X86_FEATURE_MWAIT) && mwait_usable(c)))
ea530692 1358 return;
349c004e 1359 if (!this_cpu_has(X86_FEATURE_CLFLSH))
ce5f6824 1360 return;
7b543a53 1361 if (__this_cpu_read(cpu_info.cpuid_level) < CPUID_MWAIT_LEAF)
ea530692
PA
1362 return;
1363
1364 eax = CPUID_MWAIT_LEAF;
1365 ecx = 0;
1366 native_cpuid(&eax, &ebx, &ecx, &edx);
1367
1368 /*
1369 * eax will be 0 if EDX enumeration is not valid.
1370 * Initialized below to cstate, sub_cstate value when EDX is valid.
1371 */
1372 if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED)) {
1373 eax = 0;
1374 } else {
1375 edx >>= MWAIT_SUBSTATE_SIZE;
1376 for (i = 0; i < 7 && edx; i++, edx >>= MWAIT_SUBSTATE_SIZE) {
1377 if (edx & MWAIT_SUBSTATE_MASK) {
1378 highest_cstate = i;
1379 highest_subcstate = edx & MWAIT_SUBSTATE_MASK;
1380 }
1381 }
1382 eax = (highest_cstate << MWAIT_SUBSTATE_SIZE) |
1383 (highest_subcstate - 1);
1384 }
1385
ce5f6824
PA
1386 /*
1387 * This should be a memory location in a cache line which is
1388 * unlikely to be touched by other processors. The actual
1389 * content is immaterial as it is not actually modified in any way.
1390 */
1391 mwait_ptr = &current_thread_info()->flags;
1392
a68e5c94
PA
1393 wbinvd();
1394
ea530692 1395 while (1) {
ce5f6824
PA
1396 /*
1397 * The CLFLUSH is a workaround for erratum AAI65 for
1398 * the Xeon 7400 series. It's not clear it is actually
1399 * needed, but it should be harmless in either case.
1400 * The WBINVD is insufficient due to the spurious-wakeup
1401 * case where we return around the loop.
1402 */
1403 clflush(mwait_ptr);
1404 __monitor(mwait_ptr, 0, 0);
ea530692
PA
1405 mb();
1406 __mwait(eax, 0);
1407 }
1408}
1409
1410static inline void hlt_play_dead(void)
1411{
7b543a53 1412 if (__this_cpu_read(cpu_info.x86) >= 4)
a68e5c94
PA
1413 wbinvd();
1414
ea530692 1415 while (1) {
ea530692
PA
1416 native_halt();
1417 }
1418}
1419
a21f5d88
AN
1420void native_play_dead(void)
1421{
1422 play_dead_common();
86886e55 1423 tboot_shutdown(TB_SHUTDOWN_WFS);
ea530692
PA
1424
1425 mwait_play_dead(); /* Only returns on failure */
1426 hlt_play_dead();
a21f5d88
AN
1427}
1428
69c18c15 1429#else /* ... !CONFIG_HOTPLUG_CPU */
93be71b6 1430int native_cpu_disable(void)
69c18c15
GC
1431{
1432 return -ENOSYS;
1433}
1434
93be71b6 1435void native_cpu_die(unsigned int cpu)
69c18c15
GC
1436{
1437 /* We said "no" in __cpu_disable */
1438 BUG();
1439}
a21f5d88
AN
1440
1441void native_play_dead(void)
1442{
1443 BUG();
1444}
1445
68a1c3f8 1446#endif