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1 /*
2 * x86 SMP booting functions
3 *
4 * (c) 1995 Alan Cox, Building #3 <alan@lxorguk.ukuu.org.uk>
5 * (c) 1998, 1999, 2000, 2009 Ingo Molnar <mingo@redhat.com>
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
42#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
43
44#include <linux/init.h>
45#include <linux/smp.h>
46#include <linux/export.h>
47#include <linux/sched.h>
48#include <linux/percpu.h>
49#include <linux/bootmem.h>
50#include <linux/err.h>
51#include <linux/nmi.h>
52#include <linux/tboot.h>
53#include <linux/stackprotector.h>
54#include <linux/gfp.h>
55#include <linux/cpuidle.h>
56
57#include <asm/acpi.h>
58#include <asm/desc.h>
59#include <asm/nmi.h>
60#include <asm/irq.h>
61#include <asm/realmode.h>
62#include <asm/cpu.h>
63#include <asm/numa.h>
64#include <asm/pgtable.h>
65#include <asm/tlbflush.h>
66#include <asm/mtrr.h>
67#include <asm/mwait.h>
68#include <asm/apic.h>
69#include <asm/io_apic.h>
70#include <asm/fpu/internal.h>
71#include <asm/setup.h>
72#include <asm/uv/uv.h>
73#include <linux/mc146818rtc.h>
74#include <asm/i8259.h>
75#include <asm/realmode.h>
76#include <asm/misc.h>
77
78/* Number of siblings per CPU package */
79int smp_num_siblings = 1;
80EXPORT_SYMBOL(smp_num_siblings);
81
82/* Last level cache ID of each logical CPU */
83DEFINE_PER_CPU_READ_MOSTLY(u16, cpu_llc_id) = BAD_APICID;
84
85/* representing HT siblings of each logical CPU */
86DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_sibling_map);
87EXPORT_PER_CPU_SYMBOL(cpu_sibling_map);
88
89/* representing HT and core siblings of each logical CPU */
90DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_core_map);
91EXPORT_PER_CPU_SYMBOL(cpu_core_map);
92
93DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_llc_shared_map);
94
95/* Per CPU bogomips and other parameters */
96DEFINE_PER_CPU_READ_MOSTLY(struct cpuinfo_x86, cpu_info);
97EXPORT_PER_CPU_SYMBOL(cpu_info);
98
99/* Logical package management. We might want to allocate that dynamically */
100static int *physical_to_logical_pkg __read_mostly;
101static unsigned long *physical_package_map __read_mostly;;
102static unsigned int max_physical_pkg_id __read_mostly;
103unsigned int __max_logical_packages __read_mostly;
104EXPORT_SYMBOL(__max_logical_packages);
105static unsigned int logical_packages __read_mostly;
106
107/* Maximum number of SMT threads on any online core */
108int __max_smt_threads __read_mostly;
109
110/* Flag to indicate if a complete sched domain rebuild is required */
111bool x86_topology_update;
112
113int arch_update_cpu_topology(void)
114{
115 int retval = x86_topology_update;
116
117 x86_topology_update = false;
118 return retval;
119}
120
121static inline void smpboot_setup_warm_reset_vector(unsigned long start_eip)
122{
123 unsigned long flags;
124
125 spin_lock_irqsave(&rtc_lock, flags);
126 CMOS_WRITE(0xa, 0xf);
127 spin_unlock_irqrestore(&rtc_lock, flags);
128 local_flush_tlb();
129 pr_debug("1.\n");
130 *((volatile unsigned short *)phys_to_virt(TRAMPOLINE_PHYS_HIGH)) =
131 start_eip >> 4;
132 pr_debug("2.\n");
133 *((volatile unsigned short *)phys_to_virt(TRAMPOLINE_PHYS_LOW)) =
134 start_eip & 0xf;
135 pr_debug("3.\n");
136}
137
138static inline void smpboot_restore_warm_reset_vector(void)
139{
140 unsigned long flags;
141
142 /*
143 * Install writable page 0 entry to set BIOS data area.
144 */
145 local_flush_tlb();
146
147 /*
148 * Paranoid: Set warm reset code and vector here back
149 * to default values.
150 */
151 spin_lock_irqsave(&rtc_lock, flags);
152 CMOS_WRITE(0, 0xf);
153 spin_unlock_irqrestore(&rtc_lock, flags);
154
155 *((volatile u32 *)phys_to_virt(TRAMPOLINE_PHYS_LOW)) = 0;
156}
157
158/*
159 * Report back to the Boot Processor during boot time or to the caller processor
160 * during CPU online.
161 */
162static void smp_callin(void)
163{
164 int cpuid, phys_id;
165
166 /*
167 * If waken up by an INIT in an 82489DX configuration
168 * cpu_callout_mask guarantees we don't get here before
169 * an INIT_deassert IPI reaches our local APIC, so it is
170 * now safe to touch our local APIC.
171 */
172 cpuid = smp_processor_id();
173
174 /*
175 * (This works even if the APIC is not enabled.)
176 */
177 phys_id = read_apic_id();
178
179 /*
180 * the boot CPU has finished the init stage and is spinning
181 * on callin_map until we finish. We are free to set up this
182 * CPU, first the APIC. (this is probably redundant on most
183 * boards)
184 */
185 apic_ap_setup();
186
187 /*
188 * Save our processor parameters. Note: this information
189 * is needed for clock calibration.
190 */
191 smp_store_cpu_info(cpuid);
192
193 /*
194 * Get our bogomips.
195 * Update loops_per_jiffy in cpu_data. Previous call to
196 * smp_store_cpu_info() stored a value that is close but not as
197 * accurate as the value just calculated.
198 */
199 calibrate_delay();
200 cpu_data(cpuid).loops_per_jiffy = loops_per_jiffy;
201 pr_debug("Stack at about %p\n", &cpuid);
202
203 /*
204 * This must be done before setting cpu_online_mask
205 * or calling notify_cpu_starting.
206 */
207 set_cpu_sibling_map(raw_smp_processor_id());
208 wmb();
209
210 notify_cpu_starting(cpuid);
211
212 /*
213 * Allow the master to continue.
214 */
215 cpumask_set_cpu(cpuid, cpu_callin_mask);
216}
217
218static int cpu0_logical_apicid;
219static int enable_start_cpu0;
220/*
221 * Activate a secondary processor.
222 */
223static void notrace start_secondary(void *unused)
224{
225 /*
226 * Don't put *anything* before cpu_init(), SMP booting is too
227 * fragile that we want to limit the things done here to the
228 * most necessary things.
229 */
230 cpu_init();
231 x86_cpuinit.early_percpu_clock_init();
232 preempt_disable();
233 smp_callin();
234
235 enable_start_cpu0 = 0;
236
237#ifdef CONFIG_X86_32
238 /* switch away from the initial page table */
239 load_cr3(swapper_pg_dir);
240 __flush_tlb_all();
241#endif
242
243 /* otherwise gcc will move up smp_processor_id before the cpu_init */
244 barrier();
245 /*
246 * Check TSC synchronization with the BP:
247 */
248 check_tsc_sync_target();
249
250 /*
251 * Lock vector_lock and initialize the vectors on this cpu
252 * before setting the cpu online. We must set it online with
253 * vector_lock held to prevent a concurrent setup/teardown
254 * from seeing a half valid vector space.
255 */
256 lock_vector_lock();
257 setup_vector_irq(smp_processor_id());
258 set_cpu_online(smp_processor_id(), true);
259 unlock_vector_lock();
260 cpu_set_state_online(smp_processor_id());
261 x86_platform.nmi_init();
262
263 /* enable local interrupts */
264 local_irq_enable();
265
266 /* to prevent fake stack check failure in clock setup */
267 boot_init_stack_canary();
268
269 x86_cpuinit.setup_percpu_clockev();
270
271 wmb();
272 cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
273}
274
275/**
276 * topology_update_package_map - Update the physical to logical package map
277 * @pkg: The physical package id as retrieved via CPUID
278 * @cpu: The cpu for which this is updated
279 */
280int topology_update_package_map(unsigned int pkg, unsigned int cpu)
281{
282 unsigned int new;
283
284 /* Called from early boot ? */
285 if (!physical_package_map)
286 return 0;
287
288 if (pkg >= max_physical_pkg_id)
289 return -EINVAL;
290
291 /* Set the logical package id */
292 if (test_and_set_bit(pkg, physical_package_map))
293 goto found;
294
295 if (logical_packages >= __max_logical_packages) {
296 pr_warn("Package %u of CPU %u exceeds BIOS package data %u.\n",
297 logical_packages, cpu, __max_logical_packages);
298 return -ENOSPC;
299 }
300
301 new = logical_packages++;
302 if (new != pkg) {
303 pr_info("CPU %u Converting physical %u to logical package %u\n",
304 cpu, pkg, new);
305 }
306 physical_to_logical_pkg[pkg] = new;
307
308found:
309 cpu_data(cpu).logical_proc_id = physical_to_logical_pkg[pkg];
310 return 0;
311}
312
313/**
314 * topology_phys_to_logical_pkg - Map a physical package id to a logical
315 *
316 * Returns logical package id or -1 if not found
317 */
318int topology_phys_to_logical_pkg(unsigned int phys_pkg)
319{
320 if (phys_pkg >= max_physical_pkg_id)
321 return -1;
322 return physical_to_logical_pkg[phys_pkg];
323}
324EXPORT_SYMBOL(topology_phys_to_logical_pkg);
325
326static void __init smp_init_package_map(struct cpuinfo_x86 *c, unsigned int cpu)
327{
328 unsigned int ncpus;
329 size_t size;
330
331 /*
332 * Today neither Intel nor AMD support heterogenous systems. That
333 * might change in the future....
334 *
335 * While ideally we'd want '* smp_num_siblings' in the below @ncpus
336 * computation, this won't actually work since some Intel BIOSes
337 * report inconsistent HT data when they disable HT.
338 *
339 * In particular, they reduce the APIC-IDs to only include the cores,
340 * but leave the CPUID topology to say there are (2) siblings.
341 * This means we don't know how many threads there will be until
342 * after the APIC enumeration.
343 *
344 * By not including this we'll sometimes over-estimate the number of
345 * logical packages by the amount of !present siblings, but this is
346 * still better than MAX_LOCAL_APIC.
347 *
348 * We use total_cpus not nr_cpu_ids because nr_cpu_ids can be limited
349 * on the command line leading to a similar issue as the HT disable
350 * problem because the hyperthreads are usually enumerated after the
351 * primary cores.
352 */
353 ncpus = boot_cpu_data.x86_max_cores;
354 if (!ncpus) {
355 pr_warn("x86_max_cores == zero !?!?");
356 ncpus = 1;
357 }
358
359 __max_logical_packages = DIV_ROUND_UP(total_cpus, ncpus);
360 logical_packages = 0;
361
362 /*
363 * Possibly larger than what we need as the number of apic ids per
364 * package can be smaller than the actual used apic ids.
365 */
366 max_physical_pkg_id = DIV_ROUND_UP(MAX_LOCAL_APIC, ncpus);
367 size = max_physical_pkg_id * sizeof(unsigned int);
368 physical_to_logical_pkg = kmalloc(size, GFP_KERNEL);
369 memset(physical_to_logical_pkg, 0xff, size);
370 size = BITS_TO_LONGS(max_physical_pkg_id) * sizeof(unsigned long);
371 physical_package_map = kzalloc(size, GFP_KERNEL);
372
373 pr_info("Max logical packages: %u\n", __max_logical_packages);
374
375 topology_update_package_map(c->phys_proc_id, cpu);
376}
377
378void __init smp_store_boot_cpu_info(void)
379{
380 int id = 0; /* CPU 0 */
381 struct cpuinfo_x86 *c = &cpu_data(id);
382
383 *c = boot_cpu_data;
384 c->cpu_index = id;
385 smp_init_package_map(c, id);
386}
387
388/*
389 * The bootstrap kernel entry code has set these up. Save them for
390 * a given CPU
391 */
392void smp_store_cpu_info(int id)
393{
394 struct cpuinfo_x86 *c = &cpu_data(id);
395
396 *c = boot_cpu_data;
397 c->cpu_index = id;
398 /*
399 * During boot time, CPU0 has this setup already. Save the info when
400 * bringing up AP or offlined CPU0.
401 */
402 identify_secondary_cpu(c);
403}
404
405static bool
406topology_same_node(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
407{
408 int cpu1 = c->cpu_index, cpu2 = o->cpu_index;
409
410 return (cpu_to_node(cpu1) == cpu_to_node(cpu2));
411}
412
413static bool
414topology_sane(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o, const char *name)
415{
416 int cpu1 = c->cpu_index, cpu2 = o->cpu_index;
417
418 return !WARN_ONCE(!topology_same_node(c, o),
419 "sched: CPU #%d's %s-sibling CPU #%d is not on the same node! "
420 "[node: %d != %d]. Ignoring dependency.\n",
421 cpu1, name, cpu2, cpu_to_node(cpu1), cpu_to_node(cpu2));
422}
423
424#define link_mask(mfunc, c1, c2) \
425do { \
426 cpumask_set_cpu((c1), mfunc(c2)); \
427 cpumask_set_cpu((c2), mfunc(c1)); \
428} while (0)
429
430static bool match_smt(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
431{
432 if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
433 int cpu1 = c->cpu_index, cpu2 = o->cpu_index;
434
435 if (c->phys_proc_id == o->phys_proc_id &&
436 per_cpu(cpu_llc_id, cpu1) == per_cpu(cpu_llc_id, cpu2)) {
437 if (c->cpu_core_id == o->cpu_core_id)
438 return topology_sane(c, o, "smt");
439
440 if ((c->cu_id != 0xff) &&
441 (o->cu_id != 0xff) &&
442 (c->cu_id == o->cu_id))
443 return topology_sane(c, o, "smt");
444 }
445
446 } else if (c->phys_proc_id == o->phys_proc_id &&
447 c->cpu_core_id == o->cpu_core_id) {
448 return topology_sane(c, o, "smt");
449 }
450
451 return false;
452}
453
454static bool match_llc(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
455{
456 int cpu1 = c->cpu_index, cpu2 = o->cpu_index;
457
458 if (per_cpu(cpu_llc_id, cpu1) != BAD_APICID &&
459 per_cpu(cpu_llc_id, cpu1) == per_cpu(cpu_llc_id, cpu2))
460 return topology_sane(c, o, "llc");
461
462 return false;
463}
464
465/*
466 * Unlike the other levels, we do not enforce keeping a
467 * multicore group inside a NUMA node. If this happens, we will
468 * discard the MC level of the topology later.
469 */
470static bool match_die(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
471{
472 if (c->phys_proc_id == o->phys_proc_id)
473 return true;
474 return false;
475}
476
477#if defined(CONFIG_SCHED_SMT) || defined(CONFIG_SCHED_MC)
478static inline int x86_sched_itmt_flags(void)
479{
480 return sysctl_sched_itmt_enabled ? SD_ASYM_PACKING : 0;
481}
482
483#ifdef CONFIG_SCHED_MC
484static int x86_core_flags(void)
485{
486 return cpu_core_flags() | x86_sched_itmt_flags();
487}
488#endif
489#ifdef CONFIG_SCHED_SMT
490static int x86_smt_flags(void)
491{
492 return cpu_smt_flags() | x86_sched_itmt_flags();
493}
494#endif
495#endif
496
497static struct sched_domain_topology_level x86_numa_in_package_topology[] = {
498#ifdef CONFIG_SCHED_SMT
499 { cpu_smt_mask, x86_smt_flags, SD_INIT_NAME(SMT) },
500#endif
501#ifdef CONFIG_SCHED_MC
502 { cpu_coregroup_mask, x86_core_flags, SD_INIT_NAME(MC) },
503#endif
504 { NULL, },
505};
506
507static struct sched_domain_topology_level x86_topology[] = {
508#ifdef CONFIG_SCHED_SMT
509 { cpu_smt_mask, x86_smt_flags, SD_INIT_NAME(SMT) },
510#endif
511#ifdef CONFIG_SCHED_MC
512 { cpu_coregroup_mask, x86_core_flags, SD_INIT_NAME(MC) },
513#endif
514 { cpu_cpu_mask, SD_INIT_NAME(DIE) },
515 { NULL, },
516};
517
518/*
519 * Set if a package/die has multiple NUMA nodes inside.
520 * AMD Magny-Cours and Intel Cluster-on-Die have this.
521 */
522static bool x86_has_numa_in_package;
523
524void set_cpu_sibling_map(int cpu)
525{
526 bool has_smt = smp_num_siblings > 1;
527 bool has_mp = has_smt || boot_cpu_data.x86_max_cores > 1;
528 struct cpuinfo_x86 *c = &cpu_data(cpu);
529 struct cpuinfo_x86 *o;
530 int i, threads;
531
532 cpumask_set_cpu(cpu, cpu_sibling_setup_mask);
533
534 if (!has_mp) {
535 cpumask_set_cpu(cpu, topology_sibling_cpumask(cpu));
536 cpumask_set_cpu(cpu, cpu_llc_shared_mask(cpu));
537 cpumask_set_cpu(cpu, topology_core_cpumask(cpu));
538 c->booted_cores = 1;
539 return;
540 }
541
542 for_each_cpu(i, cpu_sibling_setup_mask) {
543 o = &cpu_data(i);
544
545 if ((i == cpu) || (has_smt && match_smt(c, o)))
546 link_mask(topology_sibling_cpumask, cpu, i);
547
548 if ((i == cpu) || (has_mp && match_llc(c, o)))
549 link_mask(cpu_llc_shared_mask, cpu, i);
550
551 }
552
553 /*
554 * This needs a separate iteration over the cpus because we rely on all
555 * topology_sibling_cpumask links to be set-up.
556 */
557 for_each_cpu(i, cpu_sibling_setup_mask) {
558 o = &cpu_data(i);
559
560 if ((i == cpu) || (has_mp && match_die(c, o))) {
561 link_mask(topology_core_cpumask, cpu, i);
562
563 /*
564 * Does this new cpu bringup a new core?
565 */
566 if (cpumask_weight(
567 topology_sibling_cpumask(cpu)) == 1) {
568 /*
569 * for each core in package, increment
570 * the booted_cores for this new cpu
571 */
572 if (cpumask_first(
573 topology_sibling_cpumask(i)) == i)
574 c->booted_cores++;
575 /*
576 * increment the core count for all
577 * the other cpus in this package
578 */
579 if (i != cpu)
580 cpu_data(i).booted_cores++;
581 } else if (i != cpu && !c->booted_cores)
582 c->booted_cores = cpu_data(i).booted_cores;
583 }
584 if (match_die(c, o) && !topology_same_node(c, o))
585 x86_has_numa_in_package = true;
586 }
587
588 threads = cpumask_weight(topology_sibling_cpumask(cpu));
589 if (threads > __max_smt_threads)
590 __max_smt_threads = threads;
591}
592
593/* maps the cpu to the sched domain representing multi-core */
594const struct cpumask *cpu_coregroup_mask(int cpu)
595{
596 return cpu_llc_shared_mask(cpu);
597}
598
599static void impress_friends(void)
600{
601 int cpu;
602 unsigned long bogosum = 0;
603 /*
604 * Allow the user to impress friends.
605 */
606 pr_debug("Before bogomips\n");
607 for_each_possible_cpu(cpu)
608 if (cpumask_test_cpu(cpu, cpu_callout_mask))
609 bogosum += cpu_data(cpu).loops_per_jiffy;
610 pr_info("Total of %d processors activated (%lu.%02lu BogoMIPS)\n",
611 num_online_cpus(),
612 bogosum/(500000/HZ),
613 (bogosum/(5000/HZ))%100);
614
615 pr_debug("Before bogocount - setting activated=1\n");
616}
617
618void __inquire_remote_apic(int apicid)
619{
620 unsigned i, regs[] = { APIC_ID >> 4, APIC_LVR >> 4, APIC_SPIV >> 4 };
621 const char * const names[] = { "ID", "VERSION", "SPIV" };
622 int timeout;
623 u32 status;
624
625 pr_info("Inquiring remote APIC 0x%x...\n", apicid);
626
627 for (i = 0; i < ARRAY_SIZE(regs); i++) {
628 pr_info("... APIC 0x%x %s: ", apicid, names[i]);
629
630 /*
631 * Wait for idle.
632 */
633 status = safe_apic_wait_icr_idle();
634 if (status)
635 pr_cont("a previous APIC delivery may have failed\n");
636
637 apic_icr_write(APIC_DM_REMRD | regs[i], apicid);
638
639 timeout = 0;
640 do {
641 udelay(100);
642 status = apic_read(APIC_ICR) & APIC_ICR_RR_MASK;
643 } while (status == APIC_ICR_RR_INPROG && timeout++ < 1000);
644
645 switch (status) {
646 case APIC_ICR_RR_VALID:
647 status = apic_read(APIC_RRR);
648 pr_cont("%08x\n", status);
649 break;
650 default:
651 pr_cont("failed\n");
652 }
653 }
654}
655
656/*
657 * The Multiprocessor Specification 1.4 (1997) example code suggests
658 * that there should be a 10ms delay between the BSP asserting INIT
659 * and de-asserting INIT, when starting a remote processor.
660 * But that slows boot and resume on modern processors, which include
661 * many cores and don't require that delay.
662 *
663 * Cmdline "init_cpu_udelay=" is available to over-ride this delay.
664 * Modern processor families are quirked to remove the delay entirely.
665 */
666#define UDELAY_10MS_DEFAULT 10000
667
668static unsigned int init_udelay = UINT_MAX;
669
670static int __init cpu_init_udelay(char *str)
671{
672 get_option(&str, &init_udelay);
673
674 return 0;
675}
676early_param("cpu_init_udelay", cpu_init_udelay);
677
678static void __init smp_quirk_init_udelay(void)
679{
680 /* if cmdline changed it from default, leave it alone */
681 if (init_udelay != UINT_MAX)
682 return;
683
684 /* if modern processor, use no delay */
685 if (((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) && (boot_cpu_data.x86 == 6)) ||
686 ((boot_cpu_data.x86_vendor == X86_VENDOR_AMD) && (boot_cpu_data.x86 >= 0xF))) {
687 init_udelay = 0;
688 return;
689 }
690 /* else, use legacy delay */
691 init_udelay = UDELAY_10MS_DEFAULT;
692}
693
694/*
695 * Poke the other CPU in the eye via NMI to wake it up. Remember that the normal
696 * INIT, INIT, STARTUP sequence will reset the chip hard for us, and this
697 * won't ... remember to clear down the APIC, etc later.
698 */
699int
700wakeup_secondary_cpu_via_nmi(int apicid, unsigned long start_eip)
701{
702 unsigned long send_status, accept_status = 0;
703 int maxlvt;
704
705 /* Target chip */
706 /* Boot on the stack */
707 /* Kick the second */
708 apic_icr_write(APIC_DM_NMI | apic->dest_logical, apicid);
709
710 pr_debug("Waiting for send to finish...\n");
711 send_status = safe_apic_wait_icr_idle();
712
713 /*
714 * Give the other CPU some time to accept the IPI.
715 */
716 udelay(200);
717 if (APIC_INTEGRATED(boot_cpu_apic_version)) {
718 maxlvt = lapic_get_maxlvt();
719 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
720 apic_write(APIC_ESR, 0);
721 accept_status = (apic_read(APIC_ESR) & 0xEF);
722 }
723 pr_debug("NMI sent\n");
724
725 if (send_status)
726 pr_err("APIC never delivered???\n");
727 if (accept_status)
728 pr_err("APIC delivery error (%lx)\n", accept_status);
729
730 return (send_status | accept_status);
731}
732
733static int
734wakeup_secondary_cpu_via_init(int phys_apicid, unsigned long start_eip)
735{
736 unsigned long send_status = 0, accept_status = 0;
737 int maxlvt, num_starts, j;
738
739 maxlvt = lapic_get_maxlvt();
740
741 /*
742 * Be paranoid about clearing APIC errors.
743 */
744 if (APIC_INTEGRATED(boot_cpu_apic_version)) {
745 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
746 apic_write(APIC_ESR, 0);
747 apic_read(APIC_ESR);
748 }
749
750 pr_debug("Asserting INIT\n");
751
752 /*
753 * Turn INIT on target chip
754 */
755 /*
756 * Send IPI
757 */
758 apic_icr_write(APIC_INT_LEVELTRIG | APIC_INT_ASSERT | APIC_DM_INIT,
759 phys_apicid);
760
761 pr_debug("Waiting for send to finish...\n");
762 send_status = safe_apic_wait_icr_idle();
763
764 udelay(init_udelay);
765
766 pr_debug("Deasserting INIT\n");
767
768 /* Target chip */
769 /* Send IPI */
770 apic_icr_write(APIC_INT_LEVELTRIG | APIC_DM_INIT, phys_apicid);
771
772 pr_debug("Waiting for send to finish...\n");
773 send_status = safe_apic_wait_icr_idle();
774
775 mb();
776
777 /*
778 * Should we send STARTUP IPIs ?
779 *
780 * Determine this based on the APIC version.
781 * If we don't have an integrated APIC, don't send the STARTUP IPIs.
782 */
783 if (APIC_INTEGRATED(boot_cpu_apic_version))
784 num_starts = 2;
785 else
786 num_starts = 0;
787
788 /*
789 * Run STARTUP IPI loop.
790 */
791 pr_debug("#startup loops: %d\n", num_starts);
792
793 for (j = 1; j <= num_starts; j++) {
794 pr_debug("Sending STARTUP #%d\n", j);
795 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
796 apic_write(APIC_ESR, 0);
797 apic_read(APIC_ESR);
798 pr_debug("After apic_write\n");
799
800 /*
801 * STARTUP IPI
802 */
803
804 /* Target chip */
805 /* Boot on the stack */
806 /* Kick the second */
807 apic_icr_write(APIC_DM_STARTUP | (start_eip >> 12),
808 phys_apicid);
809
810 /*
811 * Give the other CPU some time to accept the IPI.
812 */
813 if (init_udelay == 0)
814 udelay(10);
815 else
816 udelay(300);
817
818 pr_debug("Startup point 1\n");
819
820 pr_debug("Waiting for send to finish...\n");
821 send_status = safe_apic_wait_icr_idle();
822
823 /*
824 * Give the other CPU some time to accept the IPI.
825 */
826 if (init_udelay == 0)
827 udelay(10);
828 else
829 udelay(200);
830
831 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
832 apic_write(APIC_ESR, 0);
833 accept_status = (apic_read(APIC_ESR) & 0xEF);
834 if (send_status || accept_status)
835 break;
836 }
837 pr_debug("After Startup\n");
838
839 if (send_status)
840 pr_err("APIC never delivered???\n");
841 if (accept_status)
842 pr_err("APIC delivery error (%lx)\n", accept_status);
843
844 return (send_status | accept_status);
845}
846
847/* reduce the number of lines printed when booting a large cpu count system */
848static void announce_cpu(int cpu, int apicid)
849{
850 static int current_node = -1;
851 int node = early_cpu_to_node(cpu);
852 static int width, node_width;
853
854 if (!width)
855 width = num_digits(num_possible_cpus()) + 1; /* + '#' sign */
856
857 if (!node_width)
858 node_width = num_digits(num_possible_nodes()) + 1; /* + '#' */
859
860 if (cpu == 1)
861 printk(KERN_INFO "x86: Booting SMP configuration:\n");
862
863 if (system_state == SYSTEM_BOOTING) {
864 if (node != current_node) {
865 if (current_node > (-1))
866 pr_cont("\n");
867 current_node = node;
868
869 printk(KERN_INFO ".... node %*s#%d, CPUs: ",
870 node_width - num_digits(node), " ", node);
871 }
872
873 /* Add padding for the BSP */
874 if (cpu == 1)
875 pr_cont("%*s", width + 1, " ");
876
877 pr_cont("%*s#%d", width - num_digits(cpu), " ", cpu);
878
879 } else
880 pr_info("Booting Node %d Processor %d APIC 0x%x\n",
881 node, cpu, apicid);
882}
883
884static int wakeup_cpu0_nmi(unsigned int cmd, struct pt_regs *regs)
885{
886 int cpu;
887
888 cpu = smp_processor_id();
889 if (cpu == 0 && !cpu_online(cpu) && enable_start_cpu0)
890 return NMI_HANDLED;
891
892 return NMI_DONE;
893}
894
895/*
896 * Wake up AP by INIT, INIT, STARTUP sequence.
897 *
898 * Instead of waiting for STARTUP after INITs, BSP will execute the BIOS
899 * boot-strap code which is not a desired behavior for waking up BSP. To
900 * void the boot-strap code, wake up CPU0 by NMI instead.
901 *
902 * This works to wake up soft offlined CPU0 only. If CPU0 is hard offlined
903 * (i.e. physically hot removed and then hot added), NMI won't wake it up.
904 * We'll change this code in the future to wake up hard offlined CPU0 if
905 * real platform and request are available.
906 */
907static int
908wakeup_cpu_via_init_nmi(int cpu, unsigned long start_ip, int apicid,
909 int *cpu0_nmi_registered)
910{
911 int id;
912 int boot_error;
913
914 preempt_disable();
915
916 /*
917 * Wake up AP by INIT, INIT, STARTUP sequence.
918 */
919 if (cpu) {
920 boot_error = wakeup_secondary_cpu_via_init(apicid, start_ip);
921 goto out;
922 }
923
924 /*
925 * Wake up BSP by nmi.
926 *
927 * Register a NMI handler to help wake up CPU0.
928 */
929 boot_error = register_nmi_handler(NMI_LOCAL,
930 wakeup_cpu0_nmi, 0, "wake_cpu0");
931
932 if (!boot_error) {
933 enable_start_cpu0 = 1;
934 *cpu0_nmi_registered = 1;
935 if (apic->dest_logical == APIC_DEST_LOGICAL)
936 id = cpu0_logical_apicid;
937 else
938 id = apicid;
939 boot_error = wakeup_secondary_cpu_via_nmi(id, start_ip);
940 }
941
942out:
943 preempt_enable();
944
945 return boot_error;
946}
947
948void common_cpu_up(unsigned int cpu, struct task_struct *idle)
949{
950 /* Just in case we booted with a single CPU. */
951 alternatives_enable_smp();
952
953 per_cpu(current_task, cpu) = idle;
954
955#ifdef CONFIG_X86_32
956 /* Stack for startup_32 can be just as for start_secondary onwards */
957 irq_ctx_init(cpu);
958 per_cpu(cpu_current_top_of_stack, cpu) =
959 (unsigned long)task_stack_page(idle) + THREAD_SIZE;
960#else
961 initial_gs = per_cpu_offset(cpu);
962#endif
963}
964
965/*
966 * NOTE - on most systems this is a PHYSICAL apic ID, but on multiquad
967 * (ie clustered apic addressing mode), this is a LOGICAL apic ID.
968 * Returns zero if CPU booted OK, else error code from
969 * ->wakeup_secondary_cpu.
970 */
971static int do_boot_cpu(int apicid, int cpu, struct task_struct *idle)
972{
973 volatile u32 *trampoline_status =
974 (volatile u32 *) __va(real_mode_header->trampoline_status);
975 /* start_ip had better be page-aligned! */
976 unsigned long start_ip = real_mode_header->trampoline_start;
977
978 unsigned long boot_error = 0;
979 int cpu0_nmi_registered = 0;
980 unsigned long timeout;
981
982 idle->thread.sp = (unsigned long)task_pt_regs(idle);
983 early_gdt_descr.address = (unsigned long)get_cpu_gdt_table(cpu);
984 initial_code = (unsigned long)start_secondary;
985 initial_stack = idle->thread.sp;
986
987 /*
988 * Enable the espfix hack for this CPU
989 */
990#ifdef CONFIG_X86_ESPFIX64
991 init_espfix_ap(cpu);
992#endif
993
994 /* So we see what's up */
995 announce_cpu(cpu, apicid);
996
997 /*
998 * This grunge runs the startup process for
999 * the targeted processor.
1000 */
1001
1002 if (get_uv_system_type() != UV_NON_UNIQUE_APIC) {
1003
1004 pr_debug("Setting warm reset code and vector.\n");
1005
1006 smpboot_setup_warm_reset_vector(start_ip);
1007 /*
1008 * Be paranoid about clearing APIC errors.
1009 */
1010 if (APIC_INTEGRATED(boot_cpu_apic_version)) {
1011 apic_write(APIC_ESR, 0);
1012 apic_read(APIC_ESR);
1013 }
1014 }
1015
1016 /*
1017 * AP might wait on cpu_callout_mask in cpu_init() with
1018 * cpu_initialized_mask set if previous attempt to online
1019 * it timed-out. Clear cpu_initialized_mask so that after
1020 * INIT/SIPI it could start with a clean state.
1021 */
1022 cpumask_clear_cpu(cpu, cpu_initialized_mask);
1023 smp_mb();
1024
1025 /*
1026 * Wake up a CPU in difference cases:
1027 * - Use the method in the APIC driver if it's defined
1028 * Otherwise,
1029 * - Use an INIT boot APIC message for APs or NMI for BSP.
1030 */
1031 if (apic->wakeup_secondary_cpu)
1032 boot_error = apic->wakeup_secondary_cpu(apicid, start_ip);
1033 else
1034 boot_error = wakeup_cpu_via_init_nmi(cpu, start_ip, apicid,
1035 &cpu0_nmi_registered);
1036
1037 if (!boot_error) {
1038 /*
1039 * Wait 10s total for first sign of life from AP
1040 */
1041 boot_error = -1;
1042 timeout = jiffies + 10*HZ;
1043 while (time_before(jiffies, timeout)) {
1044 if (cpumask_test_cpu(cpu, cpu_initialized_mask)) {
1045 /*
1046 * Tell AP to proceed with initialization
1047 */
1048 cpumask_set_cpu(cpu, cpu_callout_mask);
1049 boot_error = 0;
1050 break;
1051 }
1052 schedule();
1053 }
1054 }
1055
1056 if (!boot_error) {
1057 /*
1058 * Wait till AP completes initial initialization
1059 */
1060 while (!cpumask_test_cpu(cpu, cpu_callin_mask)) {
1061 /*
1062 * Allow other tasks to run while we wait for the
1063 * AP to come online. This also gives a chance
1064 * for the MTRR work(triggered by the AP coming online)
1065 * to be completed in the stop machine context.
1066 */
1067 schedule();
1068 }
1069 }
1070
1071 /* mark "stuck" area as not stuck */
1072 *trampoline_status = 0;
1073
1074 if (get_uv_system_type() != UV_NON_UNIQUE_APIC) {
1075 /*
1076 * Cleanup possible dangling ends...
1077 */
1078 smpboot_restore_warm_reset_vector();
1079 }
1080 /*
1081 * Clean up the nmi handler. Do this after the callin and callout sync
1082 * to avoid impact of possible long unregister time.
1083 */
1084 if (cpu0_nmi_registered)
1085 unregister_nmi_handler(NMI_LOCAL, "wake_cpu0");
1086
1087 return boot_error;
1088}
1089
1090int native_cpu_up(unsigned int cpu, struct task_struct *tidle)
1091{
1092 int apicid = apic->cpu_present_to_apicid(cpu);
1093 unsigned long flags;
1094 int err;
1095
1096 WARN_ON(irqs_disabled());
1097
1098 pr_debug("++++++++++++++++++++=_---CPU UP %u\n", cpu);
1099
1100 if (apicid == BAD_APICID ||
1101 !physid_isset(apicid, phys_cpu_present_map) ||
1102 !apic->apic_id_valid(apicid)) {
1103 pr_err("%s: bad cpu %d\n", __func__, cpu);
1104 return -EINVAL;
1105 }
1106
1107 /*
1108 * Already booted CPU?
1109 */
1110 if (cpumask_test_cpu(cpu, cpu_callin_mask)) {
1111 pr_debug("do_boot_cpu %d Already started\n", cpu);
1112 return -ENOSYS;
1113 }
1114
1115 /*
1116 * Save current MTRR state in case it was changed since early boot
1117 * (e.g. by the ACPI SMI) to initialize new CPUs with MTRRs in sync:
1118 */
1119 mtrr_save_state();
1120
1121 /* x86 CPUs take themselves offline, so delayed offline is OK. */
1122 err = cpu_check_up_prepare(cpu);
1123 if (err && err != -EBUSY)
1124 return err;
1125
1126 /* the FPU context is blank, nobody can own it */
1127 per_cpu(fpu_fpregs_owner_ctx, cpu) = NULL;
1128
1129 common_cpu_up(cpu, tidle);
1130
1131 err = do_boot_cpu(apicid, cpu, tidle);
1132 if (err) {
1133 pr_err("do_boot_cpu failed(%d) to wakeup CPU#%u\n", err, cpu);
1134 return -EIO;
1135 }
1136
1137 /*
1138 * Check TSC synchronization with the AP (keep irqs disabled
1139 * while doing so):
1140 */
1141 local_irq_save(flags);
1142 check_tsc_sync_source(cpu);
1143 local_irq_restore(flags);
1144
1145 while (!cpu_online(cpu)) {
1146 cpu_relax();
1147 touch_nmi_watchdog();
1148 }
1149
1150 return 0;
1151}
1152
1153/**
1154 * arch_disable_smp_support() - disables SMP support for x86 at runtime
1155 */
1156void arch_disable_smp_support(void)
1157{
1158 disable_ioapic_support();
1159}
1160
1161/*
1162 * Fall back to non SMP mode after errors.
1163 *
1164 * RED-PEN audit/test this more. I bet there is more state messed up here.
1165 */
1166static __init void disable_smp(void)
1167{
1168 pr_info("SMP disabled\n");
1169
1170 disable_ioapic_support();
1171
1172 init_cpu_present(cpumask_of(0));
1173 init_cpu_possible(cpumask_of(0));
1174
1175 if (smp_found_config)
1176 physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map);
1177 else
1178 physid_set_mask_of_physid(0, &phys_cpu_present_map);
1179 cpumask_set_cpu(0, topology_sibling_cpumask(0));
1180 cpumask_set_cpu(0, topology_core_cpumask(0));
1181}
1182
1183enum {
1184 SMP_OK,
1185 SMP_NO_CONFIG,
1186 SMP_NO_APIC,
1187 SMP_FORCE_UP,
1188};
1189
1190/*
1191 * Various sanity checks.
1192 */
1193static int __init smp_sanity_check(unsigned max_cpus)
1194{
1195 preempt_disable();
1196
1197#if !defined(CONFIG_X86_BIGSMP) && defined(CONFIG_X86_32)
1198 if (def_to_bigsmp && nr_cpu_ids > 8) {
1199 unsigned int cpu;
1200 unsigned nr;
1201
1202 pr_warn("More than 8 CPUs detected - skipping them\n"
1203 "Use CONFIG_X86_BIGSMP\n");
1204
1205 nr = 0;
1206 for_each_present_cpu(cpu) {
1207 if (nr >= 8)
1208 set_cpu_present(cpu, false);
1209 nr++;
1210 }
1211
1212 nr = 0;
1213 for_each_possible_cpu(cpu) {
1214 if (nr >= 8)
1215 set_cpu_possible(cpu, false);
1216 nr++;
1217 }
1218
1219 nr_cpu_ids = 8;
1220 }
1221#endif
1222
1223 if (!physid_isset(hard_smp_processor_id(), phys_cpu_present_map)) {
1224 pr_warn("weird, boot CPU (#%d) not listed by the BIOS\n",
1225 hard_smp_processor_id());
1226
1227 physid_set(hard_smp_processor_id(), phys_cpu_present_map);
1228 }
1229
1230 /*
1231 * If we couldn't find an SMP configuration at boot time,
1232 * get out of here now!
1233 */
1234 if (!smp_found_config && !acpi_lapic) {
1235 preempt_enable();
1236 pr_notice("SMP motherboard not detected\n");
1237 return SMP_NO_CONFIG;
1238 }
1239
1240 /*
1241 * Should not be necessary because the MP table should list the boot
1242 * CPU too, but we do it for the sake of robustness anyway.
1243 */
1244 if (!apic->check_phys_apicid_present(boot_cpu_physical_apicid)) {
1245 pr_notice("weird, boot CPU (#%d) not listed by the BIOS\n",
1246 boot_cpu_physical_apicid);
1247 physid_set(hard_smp_processor_id(), phys_cpu_present_map);
1248 }
1249 preempt_enable();
1250
1251 /*
1252 * If we couldn't find a local APIC, then get out of here now!
1253 */
1254 if (APIC_INTEGRATED(boot_cpu_apic_version) &&
1255 !boot_cpu_has(X86_FEATURE_APIC)) {
1256 if (!disable_apic) {
1257 pr_err("BIOS bug, local APIC #%d not detected!...\n",
1258 boot_cpu_physical_apicid);
1259 pr_err("... forcing use of dummy APIC emulation (tell your hw vendor)\n");
1260 }
1261 return SMP_NO_APIC;
1262 }
1263
1264 /*
1265 * If SMP should be disabled, then really disable it!
1266 */
1267 if (!max_cpus) {
1268 pr_info("SMP mode deactivated\n");
1269 return SMP_FORCE_UP;
1270 }
1271
1272 return SMP_OK;
1273}
1274
1275static void __init smp_cpu_index_default(void)
1276{
1277 int i;
1278 struct cpuinfo_x86 *c;
1279
1280 for_each_possible_cpu(i) {
1281 c = &cpu_data(i);
1282 /* mark all to hotplug */
1283 c->cpu_index = nr_cpu_ids;
1284 }
1285}
1286
1287/*
1288 * Prepare for SMP bootup. The MP table or ACPI has been read
1289 * earlier. Just do some sanity checking here and enable APIC mode.
1290 */
1291void __init native_smp_prepare_cpus(unsigned int max_cpus)
1292{
1293 unsigned int i;
1294
1295 smp_cpu_index_default();
1296
1297 /*
1298 * Setup boot CPU information
1299 */
1300 smp_store_boot_cpu_info(); /* Final full version of the data */
1301 cpumask_copy(cpu_callin_mask, cpumask_of(0));
1302 mb();
1303
1304 for_each_possible_cpu(i) {
1305 zalloc_cpumask_var(&per_cpu(cpu_sibling_map, i), GFP_KERNEL);
1306 zalloc_cpumask_var(&per_cpu(cpu_core_map, i), GFP_KERNEL);
1307 zalloc_cpumask_var(&per_cpu(cpu_llc_shared_map, i), GFP_KERNEL);
1308 }
1309
1310 /*
1311 * Set 'default' x86 topology, this matches default_topology() in that
1312 * it has NUMA nodes as a topology level. See also
1313 * native_smp_cpus_done().
1314 *
1315 * Must be done before set_cpus_sibling_map() is ran.
1316 */
1317 set_sched_topology(x86_topology);
1318
1319 set_cpu_sibling_map(0);
1320
1321 switch (smp_sanity_check(max_cpus)) {
1322 case SMP_NO_CONFIG:
1323 disable_smp();
1324 if (APIC_init_uniprocessor())
1325 pr_notice("Local APIC not detected. Using dummy APIC emulation.\n");
1326 return;
1327 case SMP_NO_APIC:
1328 disable_smp();
1329 return;
1330 case SMP_FORCE_UP:
1331 disable_smp();
1332 apic_bsp_setup(false);
1333 return;
1334 case SMP_OK:
1335 break;
1336 }
1337
1338 if (read_apic_id() != boot_cpu_physical_apicid) {
1339 panic("Boot APIC ID in local APIC unexpected (%d vs %d)",
1340 read_apic_id(), boot_cpu_physical_apicid);
1341 /* Or can we switch back to PIC here? */
1342 }
1343
1344 default_setup_apic_routing();
1345 cpu0_logical_apicid = apic_bsp_setup(false);
1346
1347 pr_info("CPU0: ");
1348 print_cpu_info(&cpu_data(0));
1349
1350 if (is_uv_system())
1351 uv_system_init();
1352
1353 set_mtrr_aps_delayed_init();
1354
1355 smp_quirk_init_udelay();
1356}
1357
1358void arch_enable_nonboot_cpus_begin(void)
1359{
1360 set_mtrr_aps_delayed_init();
1361}
1362
1363void arch_enable_nonboot_cpus_end(void)
1364{
1365 mtrr_aps_init();
1366}
1367
1368/*
1369 * Early setup to make printk work.
1370 */
1371void __init native_smp_prepare_boot_cpu(void)
1372{
1373 int me = smp_processor_id();
1374 switch_to_new_gdt(me);
1375 /* already set me in cpu_online_mask in boot_cpu_init() */
1376 cpumask_set_cpu(me, cpu_callout_mask);
1377 cpu_set_state_online(me);
1378}
1379
1380void __init native_smp_cpus_done(unsigned int max_cpus)
1381{
1382 pr_debug("Boot done\n");
1383
1384 if (x86_has_numa_in_package)
1385 set_sched_topology(x86_numa_in_package_topology);
1386
1387 nmi_selftest();
1388 impress_friends();
1389 setup_ioapic_dest();
1390 mtrr_aps_init();
1391}
1392
1393static int __initdata setup_possible_cpus = -1;
1394static int __init _setup_possible_cpus(char *str)
1395{
1396 get_option(&str, &setup_possible_cpus);
1397 return 0;
1398}
1399early_param("possible_cpus", _setup_possible_cpus);
1400
1401
1402/*
1403 * cpu_possible_mask should be static, it cannot change as cpu's
1404 * are onlined, or offlined. The reason is per-cpu data-structures
1405 * are allocated by some modules at init time, and dont expect to
1406 * do this dynamically on cpu arrival/departure.
1407 * cpu_present_mask on the other hand can change dynamically.
1408 * In case when cpu_hotplug is not compiled, then we resort to current
1409 * behaviour, which is cpu_possible == cpu_present.
1410 * - Ashok Raj
1411 *
1412 * Three ways to find out the number of additional hotplug CPUs:
1413 * - If the BIOS specified disabled CPUs in ACPI/mptables use that.
1414 * - The user can overwrite it with possible_cpus=NUM
1415 * - Otherwise don't reserve additional CPUs.
1416 * We do this because additional CPUs waste a lot of memory.
1417 * -AK
1418 */
1419__init void prefill_possible_map(void)
1420{
1421 int i, possible;
1422
1423 /* No boot processor was found in mptable or ACPI MADT */
1424 if (!num_processors) {
1425 if (boot_cpu_has(X86_FEATURE_APIC)) {
1426 int apicid = boot_cpu_physical_apicid;
1427 int cpu = hard_smp_processor_id();
1428
1429 pr_warn("Boot CPU (id %d) not listed by BIOS\n", cpu);
1430
1431 /* Make sure boot cpu is enumerated */
1432 if (apic->cpu_present_to_apicid(0) == BAD_APICID &&
1433 apic->apic_id_valid(apicid))
1434 generic_processor_info(apicid, boot_cpu_apic_version);
1435 }
1436
1437 if (!num_processors)
1438 num_processors = 1;
1439 }
1440
1441 i = setup_max_cpus ?: 1;
1442 if (setup_possible_cpus == -1) {
1443 possible = num_processors;
1444#ifdef CONFIG_HOTPLUG_CPU
1445 if (setup_max_cpus)
1446 possible += disabled_cpus;
1447#else
1448 if (possible > i)
1449 possible = i;
1450#endif
1451 } else
1452 possible = setup_possible_cpus;
1453
1454 total_cpus = max_t(int, possible, num_processors + disabled_cpus);
1455
1456 /* nr_cpu_ids could be reduced via nr_cpus= */
1457 if (possible > nr_cpu_ids) {
1458 pr_warn("%d Processors exceeds NR_CPUS limit of %d\n",
1459 possible, nr_cpu_ids);
1460 possible = nr_cpu_ids;
1461 }
1462
1463#ifdef CONFIG_HOTPLUG_CPU
1464 if (!setup_max_cpus)
1465#endif
1466 if (possible > i) {
1467 pr_warn("%d Processors exceeds max_cpus limit of %u\n",
1468 possible, setup_max_cpus);
1469 possible = i;
1470 }
1471
1472 nr_cpu_ids = possible;
1473
1474 pr_info("Allowing %d CPUs, %d hotplug CPUs\n",
1475 possible, max_t(int, possible - num_processors, 0));
1476
1477 reset_cpu_possible_mask();
1478
1479 for (i = 0; i < possible; i++)
1480 set_cpu_possible(i, true);
1481}
1482
1483#ifdef CONFIG_HOTPLUG_CPU
1484
1485/* Recompute SMT state for all CPUs on offline */
1486static void recompute_smt_state(void)
1487{
1488 int max_threads, cpu;
1489
1490 max_threads = 0;
1491 for_each_online_cpu (cpu) {
1492 int threads = cpumask_weight(topology_sibling_cpumask(cpu));
1493
1494 if (threads > max_threads)
1495 max_threads = threads;
1496 }
1497 __max_smt_threads = max_threads;
1498}
1499
1500static void remove_siblinginfo(int cpu)
1501{
1502 int sibling;
1503 struct cpuinfo_x86 *c = &cpu_data(cpu);
1504
1505 for_each_cpu(sibling, topology_core_cpumask(cpu)) {
1506 cpumask_clear_cpu(cpu, topology_core_cpumask(sibling));
1507 /*/
1508 * last thread sibling in this cpu core going down
1509 */
1510 if (cpumask_weight(topology_sibling_cpumask(cpu)) == 1)
1511 cpu_data(sibling).booted_cores--;
1512 }
1513
1514 for_each_cpu(sibling, topology_sibling_cpumask(cpu))
1515 cpumask_clear_cpu(cpu, topology_sibling_cpumask(sibling));
1516 for_each_cpu(sibling, cpu_llc_shared_mask(cpu))
1517 cpumask_clear_cpu(cpu, cpu_llc_shared_mask(sibling));
1518 cpumask_clear(cpu_llc_shared_mask(cpu));
1519 cpumask_clear(topology_sibling_cpumask(cpu));
1520 cpumask_clear(topology_core_cpumask(cpu));
1521 c->phys_proc_id = 0;
1522 c->cpu_core_id = 0;
1523 cpumask_clear_cpu(cpu, cpu_sibling_setup_mask);
1524 recompute_smt_state();
1525}
1526
1527static void remove_cpu_from_maps(int cpu)
1528{
1529 set_cpu_online(cpu, false);
1530 cpumask_clear_cpu(cpu, cpu_callout_mask);
1531 cpumask_clear_cpu(cpu, cpu_callin_mask);
1532 /* was set by cpu_init() */
1533 cpumask_clear_cpu(cpu, cpu_initialized_mask);
1534 numa_remove_cpu(cpu);
1535}
1536
1537void cpu_disable_common(void)
1538{
1539 int cpu = smp_processor_id();
1540
1541 remove_siblinginfo(cpu);
1542
1543 /* It's now safe to remove this processor from the online map */
1544 lock_vector_lock();
1545 remove_cpu_from_maps(cpu);
1546 unlock_vector_lock();
1547 fixup_irqs();
1548}
1549
1550int native_cpu_disable(void)
1551{
1552 int ret;
1553
1554 ret = check_irq_vectors_for_cpu_disable();
1555 if (ret)
1556 return ret;
1557
1558 clear_local_APIC();
1559 cpu_disable_common();
1560
1561 return 0;
1562}
1563
1564int common_cpu_die(unsigned int cpu)
1565{
1566 int ret = 0;
1567
1568 /* We don't do anything here: idle task is faking death itself. */
1569
1570 /* They ack this in play_dead() by setting CPU_DEAD */
1571 if (cpu_wait_death(cpu, 5)) {
1572 if (system_state == SYSTEM_RUNNING)
1573 pr_info("CPU %u is now offline\n", cpu);
1574 } else {
1575 pr_err("CPU %u didn't die...\n", cpu);
1576 ret = -1;
1577 }
1578
1579 return ret;
1580}
1581
1582void native_cpu_die(unsigned int cpu)
1583{
1584 common_cpu_die(cpu);
1585}
1586
1587void play_dead_common(void)
1588{
1589 idle_task_exit();
1590 reset_lazy_tlbstate();
1591
1592 /* Ack it */
1593 (void)cpu_report_death();
1594
1595 /*
1596 * With physical CPU hotplug, we should halt the cpu
1597 */
1598 local_irq_disable();
1599}
1600
1601static bool wakeup_cpu0(void)
1602{
1603 if (smp_processor_id() == 0 && enable_start_cpu0)
1604 return true;
1605
1606 return false;
1607}
1608
1609/*
1610 * We need to flush the caches before going to sleep, lest we have
1611 * dirty data in our caches when we come back up.
1612 */
1613static inline void mwait_play_dead(void)
1614{
1615 unsigned int eax, ebx, ecx, edx;
1616 unsigned int highest_cstate = 0;
1617 unsigned int highest_subcstate = 0;
1618 void *mwait_ptr;
1619 int i;
1620
1621 if (!this_cpu_has(X86_FEATURE_MWAIT))
1622 return;
1623 if (!this_cpu_has(X86_FEATURE_CLFLUSH))
1624 return;
1625 if (__this_cpu_read(cpu_info.cpuid_level) < CPUID_MWAIT_LEAF)
1626 return;
1627
1628 eax = CPUID_MWAIT_LEAF;
1629 ecx = 0;
1630 native_cpuid(&eax, &ebx, &ecx, &edx);
1631
1632 /*
1633 * eax will be 0 if EDX enumeration is not valid.
1634 * Initialized below to cstate, sub_cstate value when EDX is valid.
1635 */
1636 if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED)) {
1637 eax = 0;
1638 } else {
1639 edx >>= MWAIT_SUBSTATE_SIZE;
1640 for (i = 0; i < 7 && edx; i++, edx >>= MWAIT_SUBSTATE_SIZE) {
1641 if (edx & MWAIT_SUBSTATE_MASK) {
1642 highest_cstate = i;
1643 highest_subcstate = edx & MWAIT_SUBSTATE_MASK;
1644 }
1645 }
1646 eax = (highest_cstate << MWAIT_SUBSTATE_SIZE) |
1647 (highest_subcstate - 1);
1648 }
1649
1650 /*
1651 * This should be a memory location in a cache line which is
1652 * unlikely to be touched by other processors. The actual
1653 * content is immaterial as it is not actually modified in any way.
1654 */
1655 mwait_ptr = ¤t_thread_info()->flags;
1656
1657 wbinvd();
1658
1659 while (1) {
1660 /*
1661 * The CLFLUSH is a workaround for erratum AAI65 for
1662 * the Xeon 7400 series. It's not clear it is actually
1663 * needed, but it should be harmless in either case.
1664 * The WBINVD is insufficient due to the spurious-wakeup
1665 * case where we return around the loop.
1666 */
1667 mb();
1668 clflush(mwait_ptr);
1669 mb();
1670 __monitor(mwait_ptr, 0, 0);
1671 mb();
1672 __mwait(eax, 0);
1673 /*
1674 * If NMI wants to wake up CPU0, start CPU0.
1675 */
1676 if (wakeup_cpu0())
1677 start_cpu0();
1678 }
1679}
1680
1681void hlt_play_dead(void)
1682{
1683 if (__this_cpu_read(cpu_info.x86) >= 4)
1684 wbinvd();
1685
1686 while (1) {
1687 native_halt();
1688 /*
1689 * If NMI wants to wake up CPU0, start CPU0.
1690 */
1691 if (wakeup_cpu0())
1692 start_cpu0();
1693 }
1694}
1695
1696void native_play_dead(void)
1697{
1698 play_dead_common();
1699 tboot_shutdown(TB_SHUTDOWN_WFS);
1700
1701 mwait_play_dead(); /* Only returns on failure */
1702 if (cpuidle_play_dead())
1703 hlt_play_dead();
1704}
1705
1706#else /* ... !CONFIG_HOTPLUG_CPU */
1707int native_cpu_disable(void)
1708{
1709 return -ENOSYS;
1710}
1711
1712void native_cpu_die(unsigned int cpu)
1713{
1714 /* We said "no" in __cpu_disable */
1715 BUG();
1716}
1717
1718void native_play_dead(void)
1719{
1720 BUG();
1721}
1722
1723#endif
1// SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * x86 SMP booting functions
4 *
5 * (c) 1995 Alan Cox, Building #3 <alan@lxorguk.ukuu.org.uk>
6 * (c) 1998, 1999, 2000, 2009 Ingo Molnar <mingo@redhat.com>
7 * Copyright 2001 Andi Kleen, SuSE Labs.
8 *
9 * Much of the core SMP work is based on previous work by Thomas Radke, to
10 * whom a great many thanks are extended.
11 *
12 * Thanks to Intel for making available several different Pentium,
13 * Pentium Pro and Pentium-II/Xeon MP machines.
14 * Original development of Linux SMP code supported by Caldera.
15 *
16 * Fixes
17 * Felix Koop : NR_CPUS used properly
18 * Jose Renau : Handle single CPU case.
19 * Alan Cox : By repeated request 8) - Total BogoMIPS report.
20 * Greg Wright : Fix for kernel stacks panic.
21 * Erich Boleyn : MP v1.4 and additional changes.
22 * Matthias Sattler : Changes for 2.1 kernel map.
23 * Michel Lespinasse : Changes for 2.1 kernel map.
24 * Michael Chastain : Change trampoline.S to gnu as.
25 * Alan Cox : Dumb bug: 'B' step PPro's are fine
26 * Ingo Molnar : Added APIC timers, based on code
27 * from Jose Renau
28 * Ingo Molnar : various cleanups and rewrites
29 * Tigran Aivazian : fixed "0.00 in /proc/uptime on SMP" bug.
30 * Maciej W. Rozycki : Bits for genuine 82489DX APICs
31 * Andi Kleen : Changed for SMP boot into long mode.
32 * Martin J. Bligh : Added support for multi-quad systems
33 * Dave Jones : Report invalid combinations of Athlon CPUs.
34 * Rusty Russell : Hacked into shape for new "hotplug" boot process.
35 * Andi Kleen : Converted to new state machine.
36 * Ashok Raj : CPU hotplug support
37 * Glauber Costa : i386 and x86_64 integration
38 */
39
40#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
41
42#include <linux/init.h>
43#include <linux/smp.h>
44#include <linux/export.h>
45#include <linux/sched.h>
46#include <linux/sched/topology.h>
47#include <linux/sched/hotplug.h>
48#include <linux/sched/task_stack.h>
49#include <linux/percpu.h>
50#include <linux/memblock.h>
51#include <linux/err.h>
52#include <linux/nmi.h>
53#include <linux/tboot.h>
54#include <linux/gfp.h>
55#include <linux/cpuidle.h>
56#include <linux/numa.h>
57#include <linux/pgtable.h>
58#include <linux/overflow.h>
59#include <linux/syscore_ops.h>
60
61#include <asm/acpi.h>
62#include <asm/desc.h>
63#include <asm/nmi.h>
64#include <asm/irq.h>
65#include <asm/realmode.h>
66#include <asm/cpu.h>
67#include <asm/numa.h>
68#include <asm/tlbflush.h>
69#include <asm/mtrr.h>
70#include <asm/mwait.h>
71#include <asm/apic.h>
72#include <asm/io_apic.h>
73#include <asm/fpu/internal.h>
74#include <asm/setup.h>
75#include <asm/uv/uv.h>
76#include <linux/mc146818rtc.h>
77#include <asm/i8259.h>
78#include <asm/misc.h>
79#include <asm/qspinlock.h>
80#include <asm/intel-family.h>
81#include <asm/cpu_device_id.h>
82#include <asm/spec-ctrl.h>
83#include <asm/hw_irq.h>
84#include <asm/stackprotector.h>
85
86#ifdef CONFIG_ACPI_CPPC_LIB
87#include <acpi/cppc_acpi.h>
88#endif
89
90/* representing HT siblings of each logical CPU */
91DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_sibling_map);
92EXPORT_PER_CPU_SYMBOL(cpu_sibling_map);
93
94/* representing HT and core siblings of each logical CPU */
95DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_core_map);
96EXPORT_PER_CPU_SYMBOL(cpu_core_map);
97
98/* representing HT, core, and die siblings of each logical CPU */
99DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_die_map);
100EXPORT_PER_CPU_SYMBOL(cpu_die_map);
101
102DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_llc_shared_map);
103
104/* Per CPU bogomips and other parameters */
105DEFINE_PER_CPU_READ_MOSTLY(struct cpuinfo_x86, cpu_info);
106EXPORT_PER_CPU_SYMBOL(cpu_info);
107
108/* Logical package management. We might want to allocate that dynamically */
109unsigned int __max_logical_packages __read_mostly;
110EXPORT_SYMBOL(__max_logical_packages);
111static unsigned int logical_packages __read_mostly;
112static unsigned int logical_die __read_mostly;
113
114/* Maximum number of SMT threads on any online core */
115int __read_mostly __max_smt_threads = 1;
116
117/* Flag to indicate if a complete sched domain rebuild is required */
118bool x86_topology_update;
119
120int arch_update_cpu_topology(void)
121{
122 int retval = x86_topology_update;
123
124 x86_topology_update = false;
125 return retval;
126}
127
128static inline void smpboot_setup_warm_reset_vector(unsigned long start_eip)
129{
130 unsigned long flags;
131
132 spin_lock_irqsave(&rtc_lock, flags);
133 CMOS_WRITE(0xa, 0xf);
134 spin_unlock_irqrestore(&rtc_lock, flags);
135 *((volatile unsigned short *)phys_to_virt(TRAMPOLINE_PHYS_HIGH)) =
136 start_eip >> 4;
137 *((volatile unsigned short *)phys_to_virt(TRAMPOLINE_PHYS_LOW)) =
138 start_eip & 0xf;
139}
140
141static inline void smpboot_restore_warm_reset_vector(void)
142{
143 unsigned long flags;
144
145 /*
146 * Paranoid: Set warm reset code and vector here back
147 * to default values.
148 */
149 spin_lock_irqsave(&rtc_lock, flags);
150 CMOS_WRITE(0, 0xf);
151 spin_unlock_irqrestore(&rtc_lock, flags);
152
153 *((volatile u32 *)phys_to_virt(TRAMPOLINE_PHYS_LOW)) = 0;
154}
155
156static void init_freq_invariance(bool secondary, bool cppc_ready);
157
158/*
159 * Report back to the Boot Processor during boot time or to the caller processor
160 * during CPU online.
161 */
162static void smp_callin(void)
163{
164 int cpuid;
165
166 /*
167 * If waken up by an INIT in an 82489DX configuration
168 * cpu_callout_mask guarantees we don't get here before
169 * an INIT_deassert IPI reaches our local APIC, so it is
170 * now safe to touch our local APIC.
171 */
172 cpuid = smp_processor_id();
173
174 /*
175 * the boot CPU has finished the init stage and is spinning
176 * on callin_map until we finish. We are free to set up this
177 * CPU, first the APIC. (this is probably redundant on most
178 * boards)
179 */
180 apic_ap_setup();
181
182 /*
183 * Save our processor parameters. Note: this information
184 * is needed for clock calibration.
185 */
186 smp_store_cpu_info(cpuid);
187
188 /*
189 * The topology information must be up to date before
190 * calibrate_delay() and notify_cpu_starting().
191 */
192 set_cpu_sibling_map(raw_smp_processor_id());
193
194 init_freq_invariance(true, false);
195
196 /*
197 * Get our bogomips.
198 * Update loops_per_jiffy in cpu_data. Previous call to
199 * smp_store_cpu_info() stored a value that is close but not as
200 * accurate as the value just calculated.
201 */
202 calibrate_delay();
203 cpu_data(cpuid).loops_per_jiffy = loops_per_jiffy;
204 pr_debug("Stack at about %p\n", &cpuid);
205
206 wmb();
207
208 notify_cpu_starting(cpuid);
209
210 /*
211 * Allow the master to continue.
212 */
213 cpumask_set_cpu(cpuid, cpu_callin_mask);
214}
215
216static int cpu0_logical_apicid;
217static int enable_start_cpu0;
218/*
219 * Activate a secondary processor.
220 */
221static void notrace start_secondary(void *unused)
222{
223 /*
224 * Don't put *anything* except direct CPU state initialization
225 * before cpu_init(), SMP booting is too fragile that we want to
226 * limit the things done here to the most necessary things.
227 */
228 cr4_init();
229
230#ifdef CONFIG_X86_32
231 /* switch away from the initial page table */
232 load_cr3(swapper_pg_dir);
233 __flush_tlb_all();
234#endif
235 cpu_init_secondary();
236 rcu_cpu_starting(raw_smp_processor_id());
237 x86_cpuinit.early_percpu_clock_init();
238 smp_callin();
239
240 enable_start_cpu0 = 0;
241
242 /* otherwise gcc will move up smp_processor_id before the cpu_init */
243 barrier();
244 /*
245 * Check TSC synchronization with the boot CPU:
246 */
247 check_tsc_sync_target();
248
249 speculative_store_bypass_ht_init();
250
251 /*
252 * Lock vector_lock, set CPU online and bring the vector
253 * allocator online. Online must be set with vector_lock held
254 * to prevent a concurrent irq setup/teardown from seeing a
255 * half valid vector space.
256 */
257 lock_vector_lock();
258 set_cpu_online(smp_processor_id(), true);
259 lapic_online();
260 unlock_vector_lock();
261 cpu_set_state_online(smp_processor_id());
262 x86_platform.nmi_init();
263
264 /* enable local interrupts */
265 local_irq_enable();
266
267 x86_cpuinit.setup_percpu_clockev();
268
269 wmb();
270 cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
271}
272
273/**
274 * topology_is_primary_thread - Check whether CPU is the primary SMT thread
275 * @cpu: CPU to check
276 */
277bool topology_is_primary_thread(unsigned int cpu)
278{
279 return apic_id_is_primary_thread(per_cpu(x86_cpu_to_apicid, cpu));
280}
281
282/**
283 * topology_smt_supported - Check whether SMT is supported by the CPUs
284 */
285bool topology_smt_supported(void)
286{
287 return smp_num_siblings > 1;
288}
289
290/**
291 * topology_phys_to_logical_pkg - Map a physical package id to a logical
292 *
293 * Returns logical package id or -1 if not found
294 */
295int topology_phys_to_logical_pkg(unsigned int phys_pkg)
296{
297 int cpu;
298
299 for_each_possible_cpu(cpu) {
300 struct cpuinfo_x86 *c = &cpu_data(cpu);
301
302 if (c->initialized && c->phys_proc_id == phys_pkg)
303 return c->logical_proc_id;
304 }
305 return -1;
306}
307EXPORT_SYMBOL(topology_phys_to_logical_pkg);
308/**
309 * topology_phys_to_logical_die - Map a physical die id to logical
310 *
311 * Returns logical die id or -1 if not found
312 */
313int topology_phys_to_logical_die(unsigned int die_id, unsigned int cur_cpu)
314{
315 int cpu;
316 int proc_id = cpu_data(cur_cpu).phys_proc_id;
317
318 for_each_possible_cpu(cpu) {
319 struct cpuinfo_x86 *c = &cpu_data(cpu);
320
321 if (c->initialized && c->cpu_die_id == die_id &&
322 c->phys_proc_id == proc_id)
323 return c->logical_die_id;
324 }
325 return -1;
326}
327EXPORT_SYMBOL(topology_phys_to_logical_die);
328
329/**
330 * topology_update_package_map - Update the physical to logical package map
331 * @pkg: The physical package id as retrieved via CPUID
332 * @cpu: The cpu for which this is updated
333 */
334int topology_update_package_map(unsigned int pkg, unsigned int cpu)
335{
336 int new;
337
338 /* Already available somewhere? */
339 new = topology_phys_to_logical_pkg(pkg);
340 if (new >= 0)
341 goto found;
342
343 new = logical_packages++;
344 if (new != pkg) {
345 pr_info("CPU %u Converting physical %u to logical package %u\n",
346 cpu, pkg, new);
347 }
348found:
349 cpu_data(cpu).logical_proc_id = new;
350 return 0;
351}
352/**
353 * topology_update_die_map - Update the physical to logical die map
354 * @die: The die id as retrieved via CPUID
355 * @cpu: The cpu for which this is updated
356 */
357int topology_update_die_map(unsigned int die, unsigned int cpu)
358{
359 int new;
360
361 /* Already available somewhere? */
362 new = topology_phys_to_logical_die(die, cpu);
363 if (new >= 0)
364 goto found;
365
366 new = logical_die++;
367 if (new != die) {
368 pr_info("CPU %u Converting physical %u to logical die %u\n",
369 cpu, die, new);
370 }
371found:
372 cpu_data(cpu).logical_die_id = new;
373 return 0;
374}
375
376void __init smp_store_boot_cpu_info(void)
377{
378 int id = 0; /* CPU 0 */
379 struct cpuinfo_x86 *c = &cpu_data(id);
380
381 *c = boot_cpu_data;
382 c->cpu_index = id;
383 topology_update_package_map(c->phys_proc_id, id);
384 topology_update_die_map(c->cpu_die_id, id);
385 c->initialized = true;
386}
387
388/*
389 * The bootstrap kernel entry code has set these up. Save them for
390 * a given CPU
391 */
392void smp_store_cpu_info(int id)
393{
394 struct cpuinfo_x86 *c = &cpu_data(id);
395
396 /* Copy boot_cpu_data only on the first bringup */
397 if (!c->initialized)
398 *c = boot_cpu_data;
399 c->cpu_index = id;
400 /*
401 * During boot time, CPU0 has this setup already. Save the info when
402 * bringing up AP or offlined CPU0.
403 */
404 identify_secondary_cpu(c);
405 c->initialized = true;
406}
407
408static bool
409topology_same_node(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
410{
411 int cpu1 = c->cpu_index, cpu2 = o->cpu_index;
412
413 return (cpu_to_node(cpu1) == cpu_to_node(cpu2));
414}
415
416static bool
417topology_sane(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o, const char *name)
418{
419 int cpu1 = c->cpu_index, cpu2 = o->cpu_index;
420
421 return !WARN_ONCE(!topology_same_node(c, o),
422 "sched: CPU #%d's %s-sibling CPU #%d is not on the same node! "
423 "[node: %d != %d]. Ignoring dependency.\n",
424 cpu1, name, cpu2, cpu_to_node(cpu1), cpu_to_node(cpu2));
425}
426
427#define link_mask(mfunc, c1, c2) \
428do { \
429 cpumask_set_cpu((c1), mfunc(c2)); \
430 cpumask_set_cpu((c2), mfunc(c1)); \
431} while (0)
432
433static bool match_smt(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
434{
435 if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
436 int cpu1 = c->cpu_index, cpu2 = o->cpu_index;
437
438 if (c->phys_proc_id == o->phys_proc_id &&
439 c->cpu_die_id == o->cpu_die_id &&
440 per_cpu(cpu_llc_id, cpu1) == per_cpu(cpu_llc_id, cpu2)) {
441 if (c->cpu_core_id == o->cpu_core_id)
442 return topology_sane(c, o, "smt");
443
444 if ((c->cu_id != 0xff) &&
445 (o->cu_id != 0xff) &&
446 (c->cu_id == o->cu_id))
447 return topology_sane(c, o, "smt");
448 }
449
450 } else if (c->phys_proc_id == o->phys_proc_id &&
451 c->cpu_die_id == o->cpu_die_id &&
452 c->cpu_core_id == o->cpu_core_id) {
453 return topology_sane(c, o, "smt");
454 }
455
456 return false;
457}
458
459static bool match_die(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
460{
461 if (c->phys_proc_id == o->phys_proc_id &&
462 c->cpu_die_id == o->cpu_die_id)
463 return true;
464 return false;
465}
466
467/*
468 * Unlike the other levels, we do not enforce keeping a
469 * multicore group inside a NUMA node. If this happens, we will
470 * discard the MC level of the topology later.
471 */
472static bool match_pkg(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
473{
474 if (c->phys_proc_id == o->phys_proc_id)
475 return true;
476 return false;
477}
478
479/*
480 * Define intel_cod_cpu[] for Intel COD (Cluster-on-Die) CPUs.
481 *
482 * Any Intel CPU that has multiple nodes per package and does not
483 * match intel_cod_cpu[] has the SNC (Sub-NUMA Cluster) topology.
484 *
485 * When in SNC mode, these CPUs enumerate an LLC that is shared
486 * by multiple NUMA nodes. The LLC is shared for off-package data
487 * access but private to the NUMA node (half of the package) for
488 * on-package access. CPUID (the source of the information about
489 * the LLC) can only enumerate the cache as shared or unshared,
490 * but not this particular configuration.
491 */
492
493static const struct x86_cpu_id intel_cod_cpu[] = {
494 X86_MATCH_INTEL_FAM6_MODEL(HASWELL_X, 0), /* COD */
495 X86_MATCH_INTEL_FAM6_MODEL(BROADWELL_X, 0), /* COD */
496 X86_MATCH_INTEL_FAM6_MODEL(ANY, 1), /* SNC */
497 {}
498};
499
500static bool match_llc(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
501{
502 const struct x86_cpu_id *id = x86_match_cpu(intel_cod_cpu);
503 int cpu1 = c->cpu_index, cpu2 = o->cpu_index;
504 bool intel_snc = id && id->driver_data;
505
506 /* Do not match if we do not have a valid APICID for cpu: */
507 if (per_cpu(cpu_llc_id, cpu1) == BAD_APICID)
508 return false;
509
510 /* Do not match if LLC id does not match: */
511 if (per_cpu(cpu_llc_id, cpu1) != per_cpu(cpu_llc_id, cpu2))
512 return false;
513
514 /*
515 * Allow the SNC topology without warning. Return of false
516 * means 'c' does not share the LLC of 'o'. This will be
517 * reflected to userspace.
518 */
519 if (match_pkg(c, o) && !topology_same_node(c, o) && intel_snc)
520 return false;
521
522 return topology_sane(c, o, "llc");
523}
524
525
526#if defined(CONFIG_SCHED_SMT) || defined(CONFIG_SCHED_MC)
527static inline int x86_sched_itmt_flags(void)
528{
529 return sysctl_sched_itmt_enabled ? SD_ASYM_PACKING : 0;
530}
531
532#ifdef CONFIG_SCHED_MC
533static int x86_core_flags(void)
534{
535 return cpu_core_flags() | x86_sched_itmt_flags();
536}
537#endif
538#ifdef CONFIG_SCHED_SMT
539static int x86_smt_flags(void)
540{
541 return cpu_smt_flags() | x86_sched_itmt_flags();
542}
543#endif
544#endif
545
546static struct sched_domain_topology_level x86_numa_in_package_topology[] = {
547#ifdef CONFIG_SCHED_SMT
548 { cpu_smt_mask, x86_smt_flags, SD_INIT_NAME(SMT) },
549#endif
550#ifdef CONFIG_SCHED_MC
551 { cpu_coregroup_mask, x86_core_flags, SD_INIT_NAME(MC) },
552#endif
553 { NULL, },
554};
555
556static struct sched_domain_topology_level x86_topology[] = {
557#ifdef CONFIG_SCHED_SMT
558 { cpu_smt_mask, x86_smt_flags, SD_INIT_NAME(SMT) },
559#endif
560#ifdef CONFIG_SCHED_MC
561 { cpu_coregroup_mask, x86_core_flags, SD_INIT_NAME(MC) },
562#endif
563 { cpu_cpu_mask, SD_INIT_NAME(DIE) },
564 { NULL, },
565};
566
567/*
568 * Set if a package/die has multiple NUMA nodes inside.
569 * AMD Magny-Cours, Intel Cluster-on-Die, and Intel
570 * Sub-NUMA Clustering have this.
571 */
572static bool x86_has_numa_in_package;
573
574void set_cpu_sibling_map(int cpu)
575{
576 bool has_smt = smp_num_siblings > 1;
577 bool has_mp = has_smt || boot_cpu_data.x86_max_cores > 1;
578 struct cpuinfo_x86 *c = &cpu_data(cpu);
579 struct cpuinfo_x86 *o;
580 int i, threads;
581
582 cpumask_set_cpu(cpu, cpu_sibling_setup_mask);
583
584 if (!has_mp) {
585 cpumask_set_cpu(cpu, topology_sibling_cpumask(cpu));
586 cpumask_set_cpu(cpu, cpu_llc_shared_mask(cpu));
587 cpumask_set_cpu(cpu, topology_core_cpumask(cpu));
588 cpumask_set_cpu(cpu, topology_die_cpumask(cpu));
589 c->booted_cores = 1;
590 return;
591 }
592
593 for_each_cpu(i, cpu_sibling_setup_mask) {
594 o = &cpu_data(i);
595
596 if (match_pkg(c, o) && !topology_same_node(c, o))
597 x86_has_numa_in_package = true;
598
599 if ((i == cpu) || (has_smt && match_smt(c, o)))
600 link_mask(topology_sibling_cpumask, cpu, i);
601
602 if ((i == cpu) || (has_mp && match_llc(c, o)))
603 link_mask(cpu_llc_shared_mask, cpu, i);
604
605 if ((i == cpu) || (has_mp && match_die(c, o)))
606 link_mask(topology_die_cpumask, cpu, i);
607 }
608
609 threads = cpumask_weight(topology_sibling_cpumask(cpu));
610 if (threads > __max_smt_threads)
611 __max_smt_threads = threads;
612
613 /*
614 * This needs a separate iteration over the cpus because we rely on all
615 * topology_sibling_cpumask links to be set-up.
616 */
617 for_each_cpu(i, cpu_sibling_setup_mask) {
618 o = &cpu_data(i);
619
620 if ((i == cpu) || (has_mp && match_pkg(c, o))) {
621 link_mask(topology_core_cpumask, cpu, i);
622
623 /*
624 * Does this new cpu bringup a new core?
625 */
626 if (threads == 1) {
627 /*
628 * for each core in package, increment
629 * the booted_cores for this new cpu
630 */
631 if (cpumask_first(
632 topology_sibling_cpumask(i)) == i)
633 c->booted_cores++;
634 /*
635 * increment the core count for all
636 * the other cpus in this package
637 */
638 if (i != cpu)
639 cpu_data(i).booted_cores++;
640 } else if (i != cpu && !c->booted_cores)
641 c->booted_cores = cpu_data(i).booted_cores;
642 }
643 }
644}
645
646/* maps the cpu to the sched domain representing multi-core */
647const struct cpumask *cpu_coregroup_mask(int cpu)
648{
649 return cpu_llc_shared_mask(cpu);
650}
651
652static void impress_friends(void)
653{
654 int cpu;
655 unsigned long bogosum = 0;
656 /*
657 * Allow the user to impress friends.
658 */
659 pr_debug("Before bogomips\n");
660 for_each_possible_cpu(cpu)
661 if (cpumask_test_cpu(cpu, cpu_callout_mask))
662 bogosum += cpu_data(cpu).loops_per_jiffy;
663 pr_info("Total of %d processors activated (%lu.%02lu BogoMIPS)\n",
664 num_online_cpus(),
665 bogosum/(500000/HZ),
666 (bogosum/(5000/HZ))%100);
667
668 pr_debug("Before bogocount - setting activated=1\n");
669}
670
671void __inquire_remote_apic(int apicid)
672{
673 unsigned i, regs[] = { APIC_ID >> 4, APIC_LVR >> 4, APIC_SPIV >> 4 };
674 const char * const names[] = { "ID", "VERSION", "SPIV" };
675 int timeout;
676 u32 status;
677
678 pr_info("Inquiring remote APIC 0x%x...\n", apicid);
679
680 for (i = 0; i < ARRAY_SIZE(regs); i++) {
681 pr_info("... APIC 0x%x %s: ", apicid, names[i]);
682
683 /*
684 * Wait for idle.
685 */
686 status = safe_apic_wait_icr_idle();
687 if (status)
688 pr_cont("a previous APIC delivery may have failed\n");
689
690 apic_icr_write(APIC_DM_REMRD | regs[i], apicid);
691
692 timeout = 0;
693 do {
694 udelay(100);
695 status = apic_read(APIC_ICR) & APIC_ICR_RR_MASK;
696 } while (status == APIC_ICR_RR_INPROG && timeout++ < 1000);
697
698 switch (status) {
699 case APIC_ICR_RR_VALID:
700 status = apic_read(APIC_RRR);
701 pr_cont("%08x\n", status);
702 break;
703 default:
704 pr_cont("failed\n");
705 }
706 }
707}
708
709/*
710 * The Multiprocessor Specification 1.4 (1997) example code suggests
711 * that there should be a 10ms delay between the BSP asserting INIT
712 * and de-asserting INIT, when starting a remote processor.
713 * But that slows boot and resume on modern processors, which include
714 * many cores and don't require that delay.
715 *
716 * Cmdline "init_cpu_udelay=" is available to over-ride this delay.
717 * Modern processor families are quirked to remove the delay entirely.
718 */
719#define UDELAY_10MS_DEFAULT 10000
720
721static unsigned int init_udelay = UINT_MAX;
722
723static int __init cpu_init_udelay(char *str)
724{
725 get_option(&str, &init_udelay);
726
727 return 0;
728}
729early_param("cpu_init_udelay", cpu_init_udelay);
730
731static void __init smp_quirk_init_udelay(void)
732{
733 /* if cmdline changed it from default, leave it alone */
734 if (init_udelay != UINT_MAX)
735 return;
736
737 /* if modern processor, use no delay */
738 if (((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) && (boot_cpu_data.x86 == 6)) ||
739 ((boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) && (boot_cpu_data.x86 >= 0x18)) ||
740 ((boot_cpu_data.x86_vendor == X86_VENDOR_AMD) && (boot_cpu_data.x86 >= 0xF))) {
741 init_udelay = 0;
742 return;
743 }
744 /* else, use legacy delay */
745 init_udelay = UDELAY_10MS_DEFAULT;
746}
747
748/*
749 * Poke the other CPU in the eye via NMI to wake it up. Remember that the normal
750 * INIT, INIT, STARTUP sequence will reset the chip hard for us, and this
751 * won't ... remember to clear down the APIC, etc later.
752 */
753int
754wakeup_secondary_cpu_via_nmi(int apicid, unsigned long start_eip)
755{
756 u32 dm = apic->dest_mode_logical ? APIC_DEST_LOGICAL : APIC_DEST_PHYSICAL;
757 unsigned long send_status, accept_status = 0;
758 int maxlvt;
759
760 /* Target chip */
761 /* Boot on the stack */
762 /* Kick the second */
763 apic_icr_write(APIC_DM_NMI | dm, apicid);
764
765 pr_debug("Waiting for send to finish...\n");
766 send_status = safe_apic_wait_icr_idle();
767
768 /*
769 * Give the other CPU some time to accept the IPI.
770 */
771 udelay(200);
772 if (APIC_INTEGRATED(boot_cpu_apic_version)) {
773 maxlvt = lapic_get_maxlvt();
774 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
775 apic_write(APIC_ESR, 0);
776 accept_status = (apic_read(APIC_ESR) & 0xEF);
777 }
778 pr_debug("NMI sent\n");
779
780 if (send_status)
781 pr_err("APIC never delivered???\n");
782 if (accept_status)
783 pr_err("APIC delivery error (%lx)\n", accept_status);
784
785 return (send_status | accept_status);
786}
787
788static int
789wakeup_secondary_cpu_via_init(int phys_apicid, unsigned long start_eip)
790{
791 unsigned long send_status = 0, accept_status = 0;
792 int maxlvt, num_starts, j;
793
794 maxlvt = lapic_get_maxlvt();
795
796 /*
797 * Be paranoid about clearing APIC errors.
798 */
799 if (APIC_INTEGRATED(boot_cpu_apic_version)) {
800 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
801 apic_write(APIC_ESR, 0);
802 apic_read(APIC_ESR);
803 }
804
805 pr_debug("Asserting INIT\n");
806
807 /*
808 * Turn INIT on target chip
809 */
810 /*
811 * Send IPI
812 */
813 apic_icr_write(APIC_INT_LEVELTRIG | APIC_INT_ASSERT | APIC_DM_INIT,
814 phys_apicid);
815
816 pr_debug("Waiting for send to finish...\n");
817 send_status = safe_apic_wait_icr_idle();
818
819 udelay(init_udelay);
820
821 pr_debug("Deasserting INIT\n");
822
823 /* Target chip */
824 /* Send IPI */
825 apic_icr_write(APIC_INT_LEVELTRIG | APIC_DM_INIT, phys_apicid);
826
827 pr_debug("Waiting for send to finish...\n");
828 send_status = safe_apic_wait_icr_idle();
829
830 mb();
831
832 /*
833 * Should we send STARTUP IPIs ?
834 *
835 * Determine this based on the APIC version.
836 * If we don't have an integrated APIC, don't send the STARTUP IPIs.
837 */
838 if (APIC_INTEGRATED(boot_cpu_apic_version))
839 num_starts = 2;
840 else
841 num_starts = 0;
842
843 /*
844 * Run STARTUP IPI loop.
845 */
846 pr_debug("#startup loops: %d\n", num_starts);
847
848 for (j = 1; j <= num_starts; j++) {
849 pr_debug("Sending STARTUP #%d\n", j);
850 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
851 apic_write(APIC_ESR, 0);
852 apic_read(APIC_ESR);
853 pr_debug("After apic_write\n");
854
855 /*
856 * STARTUP IPI
857 */
858
859 /* Target chip */
860 /* Boot on the stack */
861 /* Kick the second */
862 apic_icr_write(APIC_DM_STARTUP | (start_eip >> 12),
863 phys_apicid);
864
865 /*
866 * Give the other CPU some time to accept the IPI.
867 */
868 if (init_udelay == 0)
869 udelay(10);
870 else
871 udelay(300);
872
873 pr_debug("Startup point 1\n");
874
875 pr_debug("Waiting for send to finish...\n");
876 send_status = safe_apic_wait_icr_idle();
877
878 /*
879 * Give the other CPU some time to accept the IPI.
880 */
881 if (init_udelay == 0)
882 udelay(10);
883 else
884 udelay(200);
885
886 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
887 apic_write(APIC_ESR, 0);
888 accept_status = (apic_read(APIC_ESR) & 0xEF);
889 if (send_status || accept_status)
890 break;
891 }
892 pr_debug("After Startup\n");
893
894 if (send_status)
895 pr_err("APIC never delivered???\n");
896 if (accept_status)
897 pr_err("APIC delivery error (%lx)\n", accept_status);
898
899 return (send_status | accept_status);
900}
901
902/* reduce the number of lines printed when booting a large cpu count system */
903static void announce_cpu(int cpu, int apicid)
904{
905 static int current_node = NUMA_NO_NODE;
906 int node = early_cpu_to_node(cpu);
907 static int width, node_width;
908
909 if (!width)
910 width = num_digits(num_possible_cpus()) + 1; /* + '#' sign */
911
912 if (!node_width)
913 node_width = num_digits(num_possible_nodes()) + 1; /* + '#' */
914
915 if (cpu == 1)
916 printk(KERN_INFO "x86: Booting SMP configuration:\n");
917
918 if (system_state < SYSTEM_RUNNING) {
919 if (node != current_node) {
920 if (current_node > (-1))
921 pr_cont("\n");
922 current_node = node;
923
924 printk(KERN_INFO ".... node %*s#%d, CPUs: ",
925 node_width - num_digits(node), " ", node);
926 }
927
928 /* Add padding for the BSP */
929 if (cpu == 1)
930 pr_cont("%*s", width + 1, " ");
931
932 pr_cont("%*s#%d", width - num_digits(cpu), " ", cpu);
933
934 } else
935 pr_info("Booting Node %d Processor %d APIC 0x%x\n",
936 node, cpu, apicid);
937}
938
939static int wakeup_cpu0_nmi(unsigned int cmd, struct pt_regs *regs)
940{
941 int cpu;
942
943 cpu = smp_processor_id();
944 if (cpu == 0 && !cpu_online(cpu) && enable_start_cpu0)
945 return NMI_HANDLED;
946
947 return NMI_DONE;
948}
949
950/*
951 * Wake up AP by INIT, INIT, STARTUP sequence.
952 *
953 * Instead of waiting for STARTUP after INITs, BSP will execute the BIOS
954 * boot-strap code which is not a desired behavior for waking up BSP. To
955 * void the boot-strap code, wake up CPU0 by NMI instead.
956 *
957 * This works to wake up soft offlined CPU0 only. If CPU0 is hard offlined
958 * (i.e. physically hot removed and then hot added), NMI won't wake it up.
959 * We'll change this code in the future to wake up hard offlined CPU0 if
960 * real platform and request are available.
961 */
962static int
963wakeup_cpu_via_init_nmi(int cpu, unsigned long start_ip, int apicid,
964 int *cpu0_nmi_registered)
965{
966 int id;
967 int boot_error;
968
969 preempt_disable();
970
971 /*
972 * Wake up AP by INIT, INIT, STARTUP sequence.
973 */
974 if (cpu) {
975 boot_error = wakeup_secondary_cpu_via_init(apicid, start_ip);
976 goto out;
977 }
978
979 /*
980 * Wake up BSP by nmi.
981 *
982 * Register a NMI handler to help wake up CPU0.
983 */
984 boot_error = register_nmi_handler(NMI_LOCAL,
985 wakeup_cpu0_nmi, 0, "wake_cpu0");
986
987 if (!boot_error) {
988 enable_start_cpu0 = 1;
989 *cpu0_nmi_registered = 1;
990 id = apic->dest_mode_logical ? cpu0_logical_apicid : apicid;
991 boot_error = wakeup_secondary_cpu_via_nmi(id, start_ip);
992 }
993
994out:
995 preempt_enable();
996
997 return boot_error;
998}
999
1000int common_cpu_up(unsigned int cpu, struct task_struct *idle)
1001{
1002 int ret;
1003
1004 /* Just in case we booted with a single CPU. */
1005 alternatives_enable_smp();
1006
1007 per_cpu(current_task, cpu) = idle;
1008 cpu_init_stack_canary(cpu, idle);
1009
1010 /* Initialize the interrupt stack(s) */
1011 ret = irq_init_percpu_irqstack(cpu);
1012 if (ret)
1013 return ret;
1014
1015#ifdef CONFIG_X86_32
1016 /* Stack for startup_32 can be just as for start_secondary onwards */
1017 per_cpu(cpu_current_top_of_stack, cpu) = task_top_of_stack(idle);
1018#else
1019 initial_gs = per_cpu_offset(cpu);
1020#endif
1021 return 0;
1022}
1023
1024/*
1025 * NOTE - on most systems this is a PHYSICAL apic ID, but on multiquad
1026 * (ie clustered apic addressing mode), this is a LOGICAL apic ID.
1027 * Returns zero if CPU booted OK, else error code from
1028 * ->wakeup_secondary_cpu.
1029 */
1030static int do_boot_cpu(int apicid, int cpu, struct task_struct *idle,
1031 int *cpu0_nmi_registered)
1032{
1033 /* start_ip had better be page-aligned! */
1034 unsigned long start_ip = real_mode_header->trampoline_start;
1035
1036 unsigned long boot_error = 0;
1037 unsigned long timeout;
1038
1039 idle->thread.sp = (unsigned long)task_pt_regs(idle);
1040 early_gdt_descr.address = (unsigned long)get_cpu_gdt_rw(cpu);
1041 initial_code = (unsigned long)start_secondary;
1042 initial_stack = idle->thread.sp;
1043
1044 /* Enable the espfix hack for this CPU */
1045 init_espfix_ap(cpu);
1046
1047 /* So we see what's up */
1048 announce_cpu(cpu, apicid);
1049
1050 /*
1051 * This grunge runs the startup process for
1052 * the targeted processor.
1053 */
1054
1055 if (x86_platform.legacy.warm_reset) {
1056
1057 pr_debug("Setting warm reset code and vector.\n");
1058
1059 smpboot_setup_warm_reset_vector(start_ip);
1060 /*
1061 * Be paranoid about clearing APIC errors.
1062 */
1063 if (APIC_INTEGRATED(boot_cpu_apic_version)) {
1064 apic_write(APIC_ESR, 0);
1065 apic_read(APIC_ESR);
1066 }
1067 }
1068
1069 /*
1070 * AP might wait on cpu_callout_mask in cpu_init() with
1071 * cpu_initialized_mask set if previous attempt to online
1072 * it timed-out. Clear cpu_initialized_mask so that after
1073 * INIT/SIPI it could start with a clean state.
1074 */
1075 cpumask_clear_cpu(cpu, cpu_initialized_mask);
1076 smp_mb();
1077
1078 /*
1079 * Wake up a CPU in difference cases:
1080 * - Use the method in the APIC driver if it's defined
1081 * Otherwise,
1082 * - Use an INIT boot APIC message for APs or NMI for BSP.
1083 */
1084 if (apic->wakeup_secondary_cpu)
1085 boot_error = apic->wakeup_secondary_cpu(apicid, start_ip);
1086 else
1087 boot_error = wakeup_cpu_via_init_nmi(cpu, start_ip, apicid,
1088 cpu0_nmi_registered);
1089
1090 if (!boot_error) {
1091 /*
1092 * Wait 10s total for first sign of life from AP
1093 */
1094 boot_error = -1;
1095 timeout = jiffies + 10*HZ;
1096 while (time_before(jiffies, timeout)) {
1097 if (cpumask_test_cpu(cpu, cpu_initialized_mask)) {
1098 /*
1099 * Tell AP to proceed with initialization
1100 */
1101 cpumask_set_cpu(cpu, cpu_callout_mask);
1102 boot_error = 0;
1103 break;
1104 }
1105 schedule();
1106 }
1107 }
1108
1109 if (!boot_error) {
1110 /*
1111 * Wait till AP completes initial initialization
1112 */
1113 while (!cpumask_test_cpu(cpu, cpu_callin_mask)) {
1114 /*
1115 * Allow other tasks to run while we wait for the
1116 * AP to come online. This also gives a chance
1117 * for the MTRR work(triggered by the AP coming online)
1118 * to be completed in the stop machine context.
1119 */
1120 schedule();
1121 }
1122 }
1123
1124 if (x86_platform.legacy.warm_reset) {
1125 /*
1126 * Cleanup possible dangling ends...
1127 */
1128 smpboot_restore_warm_reset_vector();
1129 }
1130
1131 return boot_error;
1132}
1133
1134int native_cpu_up(unsigned int cpu, struct task_struct *tidle)
1135{
1136 int apicid = apic->cpu_present_to_apicid(cpu);
1137 int cpu0_nmi_registered = 0;
1138 unsigned long flags;
1139 int err, ret = 0;
1140
1141 lockdep_assert_irqs_enabled();
1142
1143 pr_debug("++++++++++++++++++++=_---CPU UP %u\n", cpu);
1144
1145 if (apicid == BAD_APICID ||
1146 !physid_isset(apicid, phys_cpu_present_map) ||
1147 !apic->apic_id_valid(apicid)) {
1148 pr_err("%s: bad cpu %d\n", __func__, cpu);
1149 return -EINVAL;
1150 }
1151
1152 /*
1153 * Already booted CPU?
1154 */
1155 if (cpumask_test_cpu(cpu, cpu_callin_mask)) {
1156 pr_debug("do_boot_cpu %d Already started\n", cpu);
1157 return -ENOSYS;
1158 }
1159
1160 /*
1161 * Save current MTRR state in case it was changed since early boot
1162 * (e.g. by the ACPI SMI) to initialize new CPUs with MTRRs in sync:
1163 */
1164 mtrr_save_state();
1165
1166 /* x86 CPUs take themselves offline, so delayed offline is OK. */
1167 err = cpu_check_up_prepare(cpu);
1168 if (err && err != -EBUSY)
1169 return err;
1170
1171 /* the FPU context is blank, nobody can own it */
1172 per_cpu(fpu_fpregs_owner_ctx, cpu) = NULL;
1173
1174 err = common_cpu_up(cpu, tidle);
1175 if (err)
1176 return err;
1177
1178 err = do_boot_cpu(apicid, cpu, tidle, &cpu0_nmi_registered);
1179 if (err) {
1180 pr_err("do_boot_cpu failed(%d) to wakeup CPU#%u\n", err, cpu);
1181 ret = -EIO;
1182 goto unreg_nmi;
1183 }
1184
1185 /*
1186 * Check TSC synchronization with the AP (keep irqs disabled
1187 * while doing so):
1188 */
1189 local_irq_save(flags);
1190 check_tsc_sync_source(cpu);
1191 local_irq_restore(flags);
1192
1193 while (!cpu_online(cpu)) {
1194 cpu_relax();
1195 touch_nmi_watchdog();
1196 }
1197
1198unreg_nmi:
1199 /*
1200 * Clean up the nmi handler. Do this after the callin and callout sync
1201 * to avoid impact of possible long unregister time.
1202 */
1203 if (cpu0_nmi_registered)
1204 unregister_nmi_handler(NMI_LOCAL, "wake_cpu0");
1205
1206 return ret;
1207}
1208
1209/**
1210 * arch_disable_smp_support() - disables SMP support for x86 at runtime
1211 */
1212void arch_disable_smp_support(void)
1213{
1214 disable_ioapic_support();
1215}
1216
1217/*
1218 * Fall back to non SMP mode after errors.
1219 *
1220 * RED-PEN audit/test this more. I bet there is more state messed up here.
1221 */
1222static __init void disable_smp(void)
1223{
1224 pr_info("SMP disabled\n");
1225
1226 disable_ioapic_support();
1227
1228 init_cpu_present(cpumask_of(0));
1229 init_cpu_possible(cpumask_of(0));
1230
1231 if (smp_found_config)
1232 physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map);
1233 else
1234 physid_set_mask_of_physid(0, &phys_cpu_present_map);
1235 cpumask_set_cpu(0, topology_sibling_cpumask(0));
1236 cpumask_set_cpu(0, topology_core_cpumask(0));
1237 cpumask_set_cpu(0, topology_die_cpumask(0));
1238}
1239
1240/*
1241 * Various sanity checks.
1242 */
1243static void __init smp_sanity_check(void)
1244{
1245 preempt_disable();
1246
1247#if !defined(CONFIG_X86_BIGSMP) && defined(CONFIG_X86_32)
1248 if (def_to_bigsmp && nr_cpu_ids > 8) {
1249 unsigned int cpu;
1250 unsigned nr;
1251
1252 pr_warn("More than 8 CPUs detected - skipping them\n"
1253 "Use CONFIG_X86_BIGSMP\n");
1254
1255 nr = 0;
1256 for_each_present_cpu(cpu) {
1257 if (nr >= 8)
1258 set_cpu_present(cpu, false);
1259 nr++;
1260 }
1261
1262 nr = 0;
1263 for_each_possible_cpu(cpu) {
1264 if (nr >= 8)
1265 set_cpu_possible(cpu, false);
1266 nr++;
1267 }
1268
1269 nr_cpu_ids = 8;
1270 }
1271#endif
1272
1273 if (!physid_isset(hard_smp_processor_id(), phys_cpu_present_map)) {
1274 pr_warn("weird, boot CPU (#%d) not listed by the BIOS\n",
1275 hard_smp_processor_id());
1276
1277 physid_set(hard_smp_processor_id(), phys_cpu_present_map);
1278 }
1279
1280 /*
1281 * Should not be necessary because the MP table should list the boot
1282 * CPU too, but we do it for the sake of robustness anyway.
1283 */
1284 if (!apic->check_phys_apicid_present(boot_cpu_physical_apicid)) {
1285 pr_notice("weird, boot CPU (#%d) not listed by the BIOS\n",
1286 boot_cpu_physical_apicid);
1287 physid_set(hard_smp_processor_id(), phys_cpu_present_map);
1288 }
1289 preempt_enable();
1290}
1291
1292static void __init smp_cpu_index_default(void)
1293{
1294 int i;
1295 struct cpuinfo_x86 *c;
1296
1297 for_each_possible_cpu(i) {
1298 c = &cpu_data(i);
1299 /* mark all to hotplug */
1300 c->cpu_index = nr_cpu_ids;
1301 }
1302}
1303
1304static void __init smp_get_logical_apicid(void)
1305{
1306 if (x2apic_mode)
1307 cpu0_logical_apicid = apic_read(APIC_LDR);
1308 else
1309 cpu0_logical_apicid = GET_APIC_LOGICAL_ID(apic_read(APIC_LDR));
1310}
1311
1312/*
1313 * Prepare for SMP bootup.
1314 * @max_cpus: configured maximum number of CPUs, It is a legacy parameter
1315 * for common interface support.
1316 */
1317void __init native_smp_prepare_cpus(unsigned int max_cpus)
1318{
1319 unsigned int i;
1320
1321 smp_cpu_index_default();
1322
1323 /*
1324 * Setup boot CPU information
1325 */
1326 smp_store_boot_cpu_info(); /* Final full version of the data */
1327 cpumask_copy(cpu_callin_mask, cpumask_of(0));
1328 mb();
1329
1330 for_each_possible_cpu(i) {
1331 zalloc_cpumask_var(&per_cpu(cpu_sibling_map, i), GFP_KERNEL);
1332 zalloc_cpumask_var(&per_cpu(cpu_core_map, i), GFP_KERNEL);
1333 zalloc_cpumask_var(&per_cpu(cpu_die_map, i), GFP_KERNEL);
1334 zalloc_cpumask_var(&per_cpu(cpu_llc_shared_map, i), GFP_KERNEL);
1335 }
1336
1337 /*
1338 * Set 'default' x86 topology, this matches default_topology() in that
1339 * it has NUMA nodes as a topology level. See also
1340 * native_smp_cpus_done().
1341 *
1342 * Must be done before set_cpus_sibling_map() is ran.
1343 */
1344 set_sched_topology(x86_topology);
1345
1346 set_cpu_sibling_map(0);
1347 init_freq_invariance(false, false);
1348 smp_sanity_check();
1349
1350 switch (apic_intr_mode) {
1351 case APIC_PIC:
1352 case APIC_VIRTUAL_WIRE_NO_CONFIG:
1353 disable_smp();
1354 return;
1355 case APIC_SYMMETRIC_IO_NO_ROUTING:
1356 disable_smp();
1357 /* Setup local timer */
1358 x86_init.timers.setup_percpu_clockev();
1359 return;
1360 case APIC_VIRTUAL_WIRE:
1361 case APIC_SYMMETRIC_IO:
1362 break;
1363 }
1364
1365 /* Setup local timer */
1366 x86_init.timers.setup_percpu_clockev();
1367
1368 smp_get_logical_apicid();
1369
1370 pr_info("CPU0: ");
1371 print_cpu_info(&cpu_data(0));
1372
1373 uv_system_init();
1374
1375 set_mtrr_aps_delayed_init();
1376
1377 smp_quirk_init_udelay();
1378
1379 speculative_store_bypass_ht_init();
1380}
1381
1382void arch_thaw_secondary_cpus_begin(void)
1383{
1384 set_mtrr_aps_delayed_init();
1385}
1386
1387void arch_thaw_secondary_cpus_end(void)
1388{
1389 mtrr_aps_init();
1390}
1391
1392/*
1393 * Early setup to make printk work.
1394 */
1395void __init native_smp_prepare_boot_cpu(void)
1396{
1397 int me = smp_processor_id();
1398 switch_to_new_gdt(me);
1399 /* already set me in cpu_online_mask in boot_cpu_init() */
1400 cpumask_set_cpu(me, cpu_callout_mask);
1401 cpu_set_state_online(me);
1402 native_pv_lock_init();
1403}
1404
1405void __init calculate_max_logical_packages(void)
1406{
1407 int ncpus;
1408
1409 /*
1410 * Today neither Intel nor AMD support heterogeneous systems so
1411 * extrapolate the boot cpu's data to all packages.
1412 */
1413 ncpus = cpu_data(0).booted_cores * topology_max_smt_threads();
1414 __max_logical_packages = DIV_ROUND_UP(total_cpus, ncpus);
1415 pr_info("Max logical packages: %u\n", __max_logical_packages);
1416}
1417
1418void __init native_smp_cpus_done(unsigned int max_cpus)
1419{
1420 pr_debug("Boot done\n");
1421
1422 calculate_max_logical_packages();
1423
1424 if (x86_has_numa_in_package)
1425 set_sched_topology(x86_numa_in_package_topology);
1426
1427 nmi_selftest();
1428 impress_friends();
1429 mtrr_aps_init();
1430}
1431
1432static int __initdata setup_possible_cpus = -1;
1433static int __init _setup_possible_cpus(char *str)
1434{
1435 get_option(&str, &setup_possible_cpus);
1436 return 0;
1437}
1438early_param("possible_cpus", _setup_possible_cpus);
1439
1440
1441/*
1442 * cpu_possible_mask should be static, it cannot change as cpu's
1443 * are onlined, or offlined. The reason is per-cpu data-structures
1444 * are allocated by some modules at init time, and don't expect to
1445 * do this dynamically on cpu arrival/departure.
1446 * cpu_present_mask on the other hand can change dynamically.
1447 * In case when cpu_hotplug is not compiled, then we resort to current
1448 * behaviour, which is cpu_possible == cpu_present.
1449 * - Ashok Raj
1450 *
1451 * Three ways to find out the number of additional hotplug CPUs:
1452 * - If the BIOS specified disabled CPUs in ACPI/mptables use that.
1453 * - The user can overwrite it with possible_cpus=NUM
1454 * - Otherwise don't reserve additional CPUs.
1455 * We do this because additional CPUs waste a lot of memory.
1456 * -AK
1457 */
1458__init void prefill_possible_map(void)
1459{
1460 int i, possible;
1461
1462 /* No boot processor was found in mptable or ACPI MADT */
1463 if (!num_processors) {
1464 if (boot_cpu_has(X86_FEATURE_APIC)) {
1465 int apicid = boot_cpu_physical_apicid;
1466 int cpu = hard_smp_processor_id();
1467
1468 pr_warn("Boot CPU (id %d) not listed by BIOS\n", cpu);
1469
1470 /* Make sure boot cpu is enumerated */
1471 if (apic->cpu_present_to_apicid(0) == BAD_APICID &&
1472 apic->apic_id_valid(apicid))
1473 generic_processor_info(apicid, boot_cpu_apic_version);
1474 }
1475
1476 if (!num_processors)
1477 num_processors = 1;
1478 }
1479
1480 i = setup_max_cpus ?: 1;
1481 if (setup_possible_cpus == -1) {
1482 possible = num_processors;
1483#ifdef CONFIG_HOTPLUG_CPU
1484 if (setup_max_cpus)
1485 possible += disabled_cpus;
1486#else
1487 if (possible > i)
1488 possible = i;
1489#endif
1490 } else
1491 possible = setup_possible_cpus;
1492
1493 total_cpus = max_t(int, possible, num_processors + disabled_cpus);
1494
1495 /* nr_cpu_ids could be reduced via nr_cpus= */
1496 if (possible > nr_cpu_ids) {
1497 pr_warn("%d Processors exceeds NR_CPUS limit of %u\n",
1498 possible, nr_cpu_ids);
1499 possible = nr_cpu_ids;
1500 }
1501
1502#ifdef CONFIG_HOTPLUG_CPU
1503 if (!setup_max_cpus)
1504#endif
1505 if (possible > i) {
1506 pr_warn("%d Processors exceeds max_cpus limit of %u\n",
1507 possible, setup_max_cpus);
1508 possible = i;
1509 }
1510
1511 nr_cpu_ids = possible;
1512
1513 pr_info("Allowing %d CPUs, %d hotplug CPUs\n",
1514 possible, max_t(int, possible - num_processors, 0));
1515
1516 reset_cpu_possible_mask();
1517
1518 for (i = 0; i < possible; i++)
1519 set_cpu_possible(i, true);
1520}
1521
1522#ifdef CONFIG_HOTPLUG_CPU
1523
1524/* Recompute SMT state for all CPUs on offline */
1525static void recompute_smt_state(void)
1526{
1527 int max_threads, cpu;
1528
1529 max_threads = 0;
1530 for_each_online_cpu (cpu) {
1531 int threads = cpumask_weight(topology_sibling_cpumask(cpu));
1532
1533 if (threads > max_threads)
1534 max_threads = threads;
1535 }
1536 __max_smt_threads = max_threads;
1537}
1538
1539static void remove_siblinginfo(int cpu)
1540{
1541 int sibling;
1542 struct cpuinfo_x86 *c = &cpu_data(cpu);
1543
1544 for_each_cpu(sibling, topology_core_cpumask(cpu)) {
1545 cpumask_clear_cpu(cpu, topology_core_cpumask(sibling));
1546 /*/
1547 * last thread sibling in this cpu core going down
1548 */
1549 if (cpumask_weight(topology_sibling_cpumask(cpu)) == 1)
1550 cpu_data(sibling).booted_cores--;
1551 }
1552
1553 for_each_cpu(sibling, topology_die_cpumask(cpu))
1554 cpumask_clear_cpu(cpu, topology_die_cpumask(sibling));
1555 for_each_cpu(sibling, topology_sibling_cpumask(cpu))
1556 cpumask_clear_cpu(cpu, topology_sibling_cpumask(sibling));
1557 for_each_cpu(sibling, cpu_llc_shared_mask(cpu))
1558 cpumask_clear_cpu(cpu, cpu_llc_shared_mask(sibling));
1559 cpumask_clear(cpu_llc_shared_mask(cpu));
1560 cpumask_clear(topology_sibling_cpumask(cpu));
1561 cpumask_clear(topology_core_cpumask(cpu));
1562 cpumask_clear(topology_die_cpumask(cpu));
1563 c->cpu_core_id = 0;
1564 c->booted_cores = 0;
1565 cpumask_clear_cpu(cpu, cpu_sibling_setup_mask);
1566 recompute_smt_state();
1567}
1568
1569static void remove_cpu_from_maps(int cpu)
1570{
1571 set_cpu_online(cpu, false);
1572 cpumask_clear_cpu(cpu, cpu_callout_mask);
1573 cpumask_clear_cpu(cpu, cpu_callin_mask);
1574 /* was set by cpu_init() */
1575 cpumask_clear_cpu(cpu, cpu_initialized_mask);
1576 numa_remove_cpu(cpu);
1577}
1578
1579void cpu_disable_common(void)
1580{
1581 int cpu = smp_processor_id();
1582
1583 remove_siblinginfo(cpu);
1584
1585 /* It's now safe to remove this processor from the online map */
1586 lock_vector_lock();
1587 remove_cpu_from_maps(cpu);
1588 unlock_vector_lock();
1589 fixup_irqs();
1590 lapic_offline();
1591}
1592
1593int native_cpu_disable(void)
1594{
1595 int ret;
1596
1597 ret = lapic_can_unplug_cpu();
1598 if (ret)
1599 return ret;
1600
1601 cpu_disable_common();
1602
1603 /*
1604 * Disable the local APIC. Otherwise IPI broadcasts will reach
1605 * it. It still responds normally to INIT, NMI, SMI, and SIPI
1606 * messages.
1607 *
1608 * Disabling the APIC must happen after cpu_disable_common()
1609 * which invokes fixup_irqs().
1610 *
1611 * Disabling the APIC preserves already set bits in IRR, but
1612 * an interrupt arriving after disabling the local APIC does not
1613 * set the corresponding IRR bit.
1614 *
1615 * fixup_irqs() scans IRR for set bits so it can raise a not
1616 * yet handled interrupt on the new destination CPU via an IPI
1617 * but obviously it can't do so for IRR bits which are not set.
1618 * IOW, interrupts arriving after disabling the local APIC will
1619 * be lost.
1620 */
1621 apic_soft_disable();
1622
1623 return 0;
1624}
1625
1626int common_cpu_die(unsigned int cpu)
1627{
1628 int ret = 0;
1629
1630 /* We don't do anything here: idle task is faking death itself. */
1631
1632 /* They ack this in play_dead() by setting CPU_DEAD */
1633 if (cpu_wait_death(cpu, 5)) {
1634 if (system_state == SYSTEM_RUNNING)
1635 pr_info("CPU %u is now offline\n", cpu);
1636 } else {
1637 pr_err("CPU %u didn't die...\n", cpu);
1638 ret = -1;
1639 }
1640
1641 return ret;
1642}
1643
1644void native_cpu_die(unsigned int cpu)
1645{
1646 common_cpu_die(cpu);
1647}
1648
1649void play_dead_common(void)
1650{
1651 idle_task_exit();
1652
1653 /* Ack it */
1654 (void)cpu_report_death();
1655
1656 /*
1657 * With physical CPU hotplug, we should halt the cpu
1658 */
1659 local_irq_disable();
1660}
1661
1662/**
1663 * cond_wakeup_cpu0 - Wake up CPU0 if needed.
1664 *
1665 * If NMI wants to wake up CPU0, start CPU0.
1666 */
1667void cond_wakeup_cpu0(void)
1668{
1669 if (smp_processor_id() == 0 && enable_start_cpu0)
1670 start_cpu0();
1671}
1672EXPORT_SYMBOL_GPL(cond_wakeup_cpu0);
1673
1674/*
1675 * We need to flush the caches before going to sleep, lest we have
1676 * dirty data in our caches when we come back up.
1677 */
1678static inline void mwait_play_dead(void)
1679{
1680 unsigned int eax, ebx, ecx, edx;
1681 unsigned int highest_cstate = 0;
1682 unsigned int highest_subcstate = 0;
1683 void *mwait_ptr;
1684 int i;
1685
1686 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD ||
1687 boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
1688 return;
1689 if (!this_cpu_has(X86_FEATURE_MWAIT))
1690 return;
1691 if (!this_cpu_has(X86_FEATURE_CLFLUSH))
1692 return;
1693 if (__this_cpu_read(cpu_info.cpuid_level) < CPUID_MWAIT_LEAF)
1694 return;
1695
1696 eax = CPUID_MWAIT_LEAF;
1697 ecx = 0;
1698 native_cpuid(&eax, &ebx, &ecx, &edx);
1699
1700 /*
1701 * eax will be 0 if EDX enumeration is not valid.
1702 * Initialized below to cstate, sub_cstate value when EDX is valid.
1703 */
1704 if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED)) {
1705 eax = 0;
1706 } else {
1707 edx >>= MWAIT_SUBSTATE_SIZE;
1708 for (i = 0; i < 7 && edx; i++, edx >>= MWAIT_SUBSTATE_SIZE) {
1709 if (edx & MWAIT_SUBSTATE_MASK) {
1710 highest_cstate = i;
1711 highest_subcstate = edx & MWAIT_SUBSTATE_MASK;
1712 }
1713 }
1714 eax = (highest_cstate << MWAIT_SUBSTATE_SIZE) |
1715 (highest_subcstate - 1);
1716 }
1717
1718 /*
1719 * This should be a memory location in a cache line which is
1720 * unlikely to be touched by other processors. The actual
1721 * content is immaterial as it is not actually modified in any way.
1722 */
1723 mwait_ptr = ¤t_thread_info()->flags;
1724
1725 wbinvd();
1726
1727 while (1) {
1728 /*
1729 * The CLFLUSH is a workaround for erratum AAI65 for
1730 * the Xeon 7400 series. It's not clear it is actually
1731 * needed, but it should be harmless in either case.
1732 * The WBINVD is insufficient due to the spurious-wakeup
1733 * case where we return around the loop.
1734 */
1735 mb();
1736 clflush(mwait_ptr);
1737 mb();
1738 __monitor(mwait_ptr, 0, 0);
1739 mb();
1740 __mwait(eax, 0);
1741
1742 cond_wakeup_cpu0();
1743 }
1744}
1745
1746void hlt_play_dead(void)
1747{
1748 if (__this_cpu_read(cpu_info.x86) >= 4)
1749 wbinvd();
1750
1751 while (1) {
1752 native_halt();
1753
1754 cond_wakeup_cpu0();
1755 }
1756}
1757
1758void native_play_dead(void)
1759{
1760 play_dead_common();
1761 tboot_shutdown(TB_SHUTDOWN_WFS);
1762
1763 mwait_play_dead(); /* Only returns on failure */
1764 if (cpuidle_play_dead())
1765 hlt_play_dead();
1766}
1767
1768#else /* ... !CONFIG_HOTPLUG_CPU */
1769int native_cpu_disable(void)
1770{
1771 return -ENOSYS;
1772}
1773
1774void native_cpu_die(unsigned int cpu)
1775{
1776 /* We said "no" in __cpu_disable */
1777 BUG();
1778}
1779
1780void native_play_dead(void)
1781{
1782 BUG();
1783}
1784
1785#endif
1786
1787#ifdef CONFIG_X86_64
1788/*
1789 * APERF/MPERF frequency ratio computation.
1790 *
1791 * The scheduler wants to do frequency invariant accounting and needs a <1
1792 * ratio to account for the 'current' frequency, corresponding to
1793 * freq_curr / freq_max.
1794 *
1795 * Since the frequency freq_curr on x86 is controlled by micro-controller and
1796 * our P-state setting is little more than a request/hint, we need to observe
1797 * the effective frequency 'BusyMHz', i.e. the average frequency over a time
1798 * interval after discarding idle time. This is given by:
1799 *
1800 * BusyMHz = delta_APERF / delta_MPERF * freq_base
1801 *
1802 * where freq_base is the max non-turbo P-state.
1803 *
1804 * The freq_max term has to be set to a somewhat arbitrary value, because we
1805 * can't know which turbo states will be available at a given point in time:
1806 * it all depends on the thermal headroom of the entire package. We set it to
1807 * the turbo level with 4 cores active.
1808 *
1809 * Benchmarks show that's a good compromise between the 1C turbo ratio
1810 * (freq_curr/freq_max would rarely reach 1) and something close to freq_base,
1811 * which would ignore the entire turbo range (a conspicuous part, making
1812 * freq_curr/freq_max always maxed out).
1813 *
1814 * An exception to the heuristic above is the Atom uarch, where we choose the
1815 * highest turbo level for freq_max since Atom's are generally oriented towards
1816 * power efficiency.
1817 *
1818 * Setting freq_max to anything less than the 1C turbo ratio makes the ratio
1819 * freq_curr / freq_max to eventually grow >1, in which case we clip it to 1.
1820 */
1821
1822DEFINE_STATIC_KEY_FALSE(arch_scale_freq_key);
1823
1824static DEFINE_PER_CPU(u64, arch_prev_aperf);
1825static DEFINE_PER_CPU(u64, arch_prev_mperf);
1826static u64 arch_turbo_freq_ratio = SCHED_CAPACITY_SCALE;
1827static u64 arch_max_freq_ratio = SCHED_CAPACITY_SCALE;
1828
1829void arch_set_max_freq_ratio(bool turbo_disabled)
1830{
1831 arch_max_freq_ratio = turbo_disabled ? SCHED_CAPACITY_SCALE :
1832 arch_turbo_freq_ratio;
1833}
1834EXPORT_SYMBOL_GPL(arch_set_max_freq_ratio);
1835
1836static bool turbo_disabled(void)
1837{
1838 u64 misc_en;
1839 int err;
1840
1841 err = rdmsrl_safe(MSR_IA32_MISC_ENABLE, &misc_en);
1842 if (err)
1843 return false;
1844
1845 return (misc_en & MSR_IA32_MISC_ENABLE_TURBO_DISABLE);
1846}
1847
1848static bool slv_set_max_freq_ratio(u64 *base_freq, u64 *turbo_freq)
1849{
1850 int err;
1851
1852 err = rdmsrl_safe(MSR_ATOM_CORE_RATIOS, base_freq);
1853 if (err)
1854 return false;
1855
1856 err = rdmsrl_safe(MSR_ATOM_CORE_TURBO_RATIOS, turbo_freq);
1857 if (err)
1858 return false;
1859
1860 *base_freq = (*base_freq >> 16) & 0x3F; /* max P state */
1861 *turbo_freq = *turbo_freq & 0x3F; /* 1C turbo */
1862
1863 return true;
1864}
1865
1866#define X86_MATCH(model) \
1867 X86_MATCH_VENDOR_FAM_MODEL_FEATURE(INTEL, 6, \
1868 INTEL_FAM6_##model, X86_FEATURE_APERFMPERF, NULL)
1869
1870static const struct x86_cpu_id has_knl_turbo_ratio_limits[] = {
1871 X86_MATCH(XEON_PHI_KNL),
1872 X86_MATCH(XEON_PHI_KNM),
1873 {}
1874};
1875
1876static const struct x86_cpu_id has_skx_turbo_ratio_limits[] = {
1877 X86_MATCH(SKYLAKE_X),
1878 {}
1879};
1880
1881static const struct x86_cpu_id has_glm_turbo_ratio_limits[] = {
1882 X86_MATCH(ATOM_GOLDMONT),
1883 X86_MATCH(ATOM_GOLDMONT_D),
1884 X86_MATCH(ATOM_GOLDMONT_PLUS),
1885 {}
1886};
1887
1888static bool knl_set_max_freq_ratio(u64 *base_freq, u64 *turbo_freq,
1889 int num_delta_fratio)
1890{
1891 int fratio, delta_fratio, found;
1892 int err, i;
1893 u64 msr;
1894
1895 err = rdmsrl_safe(MSR_PLATFORM_INFO, base_freq);
1896 if (err)
1897 return false;
1898
1899 *base_freq = (*base_freq >> 8) & 0xFF; /* max P state */
1900
1901 err = rdmsrl_safe(MSR_TURBO_RATIO_LIMIT, &msr);
1902 if (err)
1903 return false;
1904
1905 fratio = (msr >> 8) & 0xFF;
1906 i = 16;
1907 found = 0;
1908 do {
1909 if (found >= num_delta_fratio) {
1910 *turbo_freq = fratio;
1911 return true;
1912 }
1913
1914 delta_fratio = (msr >> (i + 5)) & 0x7;
1915
1916 if (delta_fratio) {
1917 found += 1;
1918 fratio -= delta_fratio;
1919 }
1920
1921 i += 8;
1922 } while (i < 64);
1923
1924 return true;
1925}
1926
1927static bool skx_set_max_freq_ratio(u64 *base_freq, u64 *turbo_freq, int size)
1928{
1929 u64 ratios, counts;
1930 u32 group_size;
1931 int err, i;
1932
1933 err = rdmsrl_safe(MSR_PLATFORM_INFO, base_freq);
1934 if (err)
1935 return false;
1936
1937 *base_freq = (*base_freq >> 8) & 0xFF; /* max P state */
1938
1939 err = rdmsrl_safe(MSR_TURBO_RATIO_LIMIT, &ratios);
1940 if (err)
1941 return false;
1942
1943 err = rdmsrl_safe(MSR_TURBO_RATIO_LIMIT1, &counts);
1944 if (err)
1945 return false;
1946
1947 for (i = 0; i < 64; i += 8) {
1948 group_size = (counts >> i) & 0xFF;
1949 if (group_size >= size) {
1950 *turbo_freq = (ratios >> i) & 0xFF;
1951 return true;
1952 }
1953 }
1954
1955 return false;
1956}
1957
1958static bool core_set_max_freq_ratio(u64 *base_freq, u64 *turbo_freq)
1959{
1960 u64 msr;
1961 int err;
1962
1963 err = rdmsrl_safe(MSR_PLATFORM_INFO, base_freq);
1964 if (err)
1965 return false;
1966
1967 err = rdmsrl_safe(MSR_TURBO_RATIO_LIMIT, &msr);
1968 if (err)
1969 return false;
1970
1971 *base_freq = (*base_freq >> 8) & 0xFF; /* max P state */
1972 *turbo_freq = (msr >> 24) & 0xFF; /* 4C turbo */
1973
1974 /* The CPU may have less than 4 cores */
1975 if (!*turbo_freq)
1976 *turbo_freq = msr & 0xFF; /* 1C turbo */
1977
1978 return true;
1979}
1980
1981static bool intel_set_max_freq_ratio(void)
1982{
1983 u64 base_freq, turbo_freq;
1984 u64 turbo_ratio;
1985
1986 if (slv_set_max_freq_ratio(&base_freq, &turbo_freq))
1987 goto out;
1988
1989 if (x86_match_cpu(has_glm_turbo_ratio_limits) &&
1990 skx_set_max_freq_ratio(&base_freq, &turbo_freq, 1))
1991 goto out;
1992
1993 if (x86_match_cpu(has_knl_turbo_ratio_limits) &&
1994 knl_set_max_freq_ratio(&base_freq, &turbo_freq, 1))
1995 goto out;
1996
1997 if (x86_match_cpu(has_skx_turbo_ratio_limits) &&
1998 skx_set_max_freq_ratio(&base_freq, &turbo_freq, 4))
1999 goto out;
2000
2001 if (core_set_max_freq_ratio(&base_freq, &turbo_freq))
2002 goto out;
2003
2004 return false;
2005
2006out:
2007 /*
2008 * Some hypervisors advertise X86_FEATURE_APERFMPERF
2009 * but then fill all MSR's with zeroes.
2010 * Some CPUs have turbo boost but don't declare any turbo ratio
2011 * in MSR_TURBO_RATIO_LIMIT.
2012 */
2013 if (!base_freq || !turbo_freq) {
2014 pr_debug("Couldn't determine cpu base or turbo frequency, necessary for scale-invariant accounting.\n");
2015 return false;
2016 }
2017
2018 turbo_ratio = div_u64(turbo_freq * SCHED_CAPACITY_SCALE, base_freq);
2019 if (!turbo_ratio) {
2020 pr_debug("Non-zero turbo and base frequencies led to a 0 ratio.\n");
2021 return false;
2022 }
2023
2024 arch_turbo_freq_ratio = turbo_ratio;
2025 arch_set_max_freq_ratio(turbo_disabled());
2026
2027 return true;
2028}
2029
2030#ifdef CONFIG_ACPI_CPPC_LIB
2031static bool amd_set_max_freq_ratio(void)
2032{
2033 struct cppc_perf_caps perf_caps;
2034 u64 highest_perf, nominal_perf;
2035 u64 perf_ratio;
2036 int rc;
2037
2038 rc = cppc_get_perf_caps(0, &perf_caps);
2039 if (rc) {
2040 pr_debug("Could not retrieve perf counters (%d)\n", rc);
2041 return false;
2042 }
2043
2044 highest_perf = amd_get_highest_perf();
2045 nominal_perf = perf_caps.nominal_perf;
2046
2047 if (!highest_perf || !nominal_perf) {
2048 pr_debug("Could not retrieve highest or nominal performance\n");
2049 return false;
2050 }
2051
2052 perf_ratio = div_u64(highest_perf * SCHED_CAPACITY_SCALE, nominal_perf);
2053 /* midpoint between max_boost and max_P */
2054 perf_ratio = (perf_ratio + SCHED_CAPACITY_SCALE) >> 1;
2055 if (!perf_ratio) {
2056 pr_debug("Non-zero highest/nominal perf values led to a 0 ratio\n");
2057 return false;
2058 }
2059
2060 arch_turbo_freq_ratio = perf_ratio;
2061 arch_set_max_freq_ratio(false);
2062
2063 return true;
2064}
2065#else
2066static bool amd_set_max_freq_ratio(void)
2067{
2068 return false;
2069}
2070#endif
2071
2072static void init_counter_refs(void)
2073{
2074 u64 aperf, mperf;
2075
2076 rdmsrl(MSR_IA32_APERF, aperf);
2077 rdmsrl(MSR_IA32_MPERF, mperf);
2078
2079 this_cpu_write(arch_prev_aperf, aperf);
2080 this_cpu_write(arch_prev_mperf, mperf);
2081}
2082
2083#ifdef CONFIG_PM_SLEEP
2084static struct syscore_ops freq_invariance_syscore_ops = {
2085 .resume = init_counter_refs,
2086};
2087
2088static void register_freq_invariance_syscore_ops(void)
2089{
2090 /* Bail out if registered already. */
2091 if (freq_invariance_syscore_ops.node.prev)
2092 return;
2093
2094 register_syscore_ops(&freq_invariance_syscore_ops);
2095}
2096#else
2097static inline void register_freq_invariance_syscore_ops(void) {}
2098#endif
2099
2100static void init_freq_invariance(bool secondary, bool cppc_ready)
2101{
2102 bool ret = false;
2103
2104 if (!boot_cpu_has(X86_FEATURE_APERFMPERF))
2105 return;
2106
2107 if (secondary) {
2108 if (static_branch_likely(&arch_scale_freq_key)) {
2109 init_counter_refs();
2110 }
2111 return;
2112 }
2113
2114 if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
2115 ret = intel_set_max_freq_ratio();
2116 else if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) {
2117 if (!cppc_ready) {
2118 return;
2119 }
2120 ret = amd_set_max_freq_ratio();
2121 }
2122
2123 if (ret) {
2124 init_counter_refs();
2125 static_branch_enable(&arch_scale_freq_key);
2126 register_freq_invariance_syscore_ops();
2127 pr_info("Estimated ratio of average max frequency by base frequency (times 1024): %llu\n", arch_max_freq_ratio);
2128 } else {
2129 pr_debug("Couldn't determine max cpu frequency, necessary for scale-invariant accounting.\n");
2130 }
2131}
2132
2133#ifdef CONFIG_ACPI_CPPC_LIB
2134static DEFINE_MUTEX(freq_invariance_lock);
2135
2136void init_freq_invariance_cppc(void)
2137{
2138 static bool secondary;
2139
2140 mutex_lock(&freq_invariance_lock);
2141
2142 init_freq_invariance(secondary, true);
2143 secondary = true;
2144
2145 mutex_unlock(&freq_invariance_lock);
2146}
2147#endif
2148
2149static void disable_freq_invariance_workfn(struct work_struct *work)
2150{
2151 static_branch_disable(&arch_scale_freq_key);
2152}
2153
2154static DECLARE_WORK(disable_freq_invariance_work,
2155 disable_freq_invariance_workfn);
2156
2157DEFINE_PER_CPU(unsigned long, arch_freq_scale) = SCHED_CAPACITY_SCALE;
2158
2159void arch_scale_freq_tick(void)
2160{
2161 u64 freq_scale = SCHED_CAPACITY_SCALE;
2162 u64 aperf, mperf;
2163 u64 acnt, mcnt;
2164
2165 if (!arch_scale_freq_invariant())
2166 return;
2167
2168 rdmsrl(MSR_IA32_APERF, aperf);
2169 rdmsrl(MSR_IA32_MPERF, mperf);
2170
2171 acnt = aperf - this_cpu_read(arch_prev_aperf);
2172 mcnt = mperf - this_cpu_read(arch_prev_mperf);
2173
2174 this_cpu_write(arch_prev_aperf, aperf);
2175 this_cpu_write(arch_prev_mperf, mperf);
2176
2177 if (check_shl_overflow(acnt, 2*SCHED_CAPACITY_SHIFT, &acnt))
2178 goto error;
2179
2180 if (check_mul_overflow(mcnt, arch_max_freq_ratio, &mcnt) || !mcnt)
2181 goto error;
2182
2183 freq_scale = div64_u64(acnt, mcnt);
2184 if (!freq_scale)
2185 goto error;
2186
2187 if (freq_scale > SCHED_CAPACITY_SCALE)
2188 freq_scale = SCHED_CAPACITY_SCALE;
2189
2190 this_cpu_write(arch_freq_scale, freq_scale);
2191 return;
2192
2193error:
2194 pr_warn("Scheduler frequency invariance went wobbly, disabling!\n");
2195 schedule_work(&disable_freq_invariance_work);
2196}
2197#else
2198static inline void init_freq_invariance(bool secondary, bool cppc_ready)
2199{
2200}
2201#endif /* CONFIG_X86_64 */