2 * x86 SMP booting functions
4 * (c) 1995 Alan Cox, Building #3 <alan@redhat.com>
5 * (c) 1998, 1999, 2000 Ingo Molnar <mingo@redhat.com>
6 * Copyright 2001 Andi Kleen, SuSE Labs.
8 * Much of the core SMP work is based on previous work by Thomas Radke, to
9 * whom a great many thanks are extended.
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.
15 * This code is released under the GNU General Public License version 2 or
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
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
42 #include <linux/init.h>
43 #include <linux/smp.h>
44 #include <linux/module.h>
45 #include <linux/sched.h>
46 #include <linux/percpu.h>
47 #include <linux/bootmem.h>
48 #include <linux/err.h>
49 #include <linux/nmi.h>
57 #include <asm/trampoline.h>
60 #include <asm/pgtable.h>
61 #include <asm/tlbflush.h>
64 #include <asm/genapic.h>
65 #include <asm/setup.h>
66 #include <linux/mc146818rtc.h>
68 #include <mach_apic.h>
69 #include <mach_wakecpu.h>
70 #include <smpboot_hooks.h>
73 u8 apicid_2_node[MAX_APICID];
74 static int low_mappings;
77 /* State of each CPU */
78 DEFINE_PER_CPU(int, cpu_state) = { 0 };
80 /* Store all idle threads, this can be reused instead of creating
81 * a new thread. Also avoids complicated thread destroy functionality
84 #ifdef CONFIG_HOTPLUG_CPU
86 * Needed only for CONFIG_HOTPLUG_CPU because __cpuinitdata is
87 * removed after init for !CONFIG_HOTPLUG_CPU.
89 static DEFINE_PER_CPU(struct task_struct *, idle_thread_array);
90 #define get_idle_for_cpu(x) (per_cpu(idle_thread_array, x))
91 #define set_idle_for_cpu(x, p) (per_cpu(idle_thread_array, x) = (p))
93 static struct task_struct *idle_thread_array[NR_CPUS] __cpuinitdata ;
94 #define get_idle_for_cpu(x) (idle_thread_array[(x)])
95 #define set_idle_for_cpu(x, p) (idle_thread_array[(x)] = (p))
98 /* Number of siblings per CPU package */
99 int smp_num_siblings = 1;
100 EXPORT_SYMBOL(smp_num_siblings);
102 /* Last level cache ID of each logical CPU */
103 DEFINE_PER_CPU(u16, cpu_llc_id) = BAD_APICID;
105 cpumask_t cpu_callin_map;
106 cpumask_t cpu_callout_map;
108 /* representing HT siblings of each logical CPU */
109 DEFINE_PER_CPU(cpumask_t, cpu_sibling_map);
110 EXPORT_PER_CPU_SYMBOL(cpu_sibling_map);
112 /* representing HT and core siblings of each logical CPU */
113 DEFINE_PER_CPU(cpumask_t, cpu_core_map);
114 EXPORT_PER_CPU_SYMBOL(cpu_core_map);
116 /* Per CPU bogomips and other parameters */
117 DEFINE_PER_CPU_SHARED_ALIGNED(struct cpuinfo_x86, cpu_info);
118 EXPORT_PER_CPU_SYMBOL(cpu_info);
120 static atomic_t init_deasserted;
123 /* representing cpus for which sibling maps can be computed */
124 static cpumask_t cpu_sibling_setup_map;
126 /* Set if we find a B stepping CPU */
127 static int __cpuinitdata smp_b_stepping;
129 #if defined(CONFIG_NUMA) && defined(CONFIG_X86_32)
131 /* which logical CPUs are on which nodes */
132 cpumask_t node_to_cpumask_map[MAX_NUMNODES] __read_mostly =
133 { [0 ... MAX_NUMNODES-1] = CPU_MASK_NONE };
134 EXPORT_SYMBOL(node_to_cpumask_map);
135 /* which node each logical CPU is on */
136 int cpu_to_node_map[NR_CPUS] __read_mostly = { [0 ... NR_CPUS-1] = 0 };
137 EXPORT_SYMBOL(cpu_to_node_map);
139 /* set up a mapping between cpu and node. */
140 static void map_cpu_to_node(int cpu, int node)
142 printk(KERN_INFO "Mapping cpu %d to node %d\n", cpu, node);
143 cpu_set(cpu, node_to_cpumask_map[node]);
144 cpu_to_node_map[cpu] = node;
147 /* undo a mapping between cpu and node. */
148 static void unmap_cpu_to_node(int cpu)
152 printk(KERN_INFO "Unmapping cpu %d from all nodes\n", cpu);
153 for (node = 0; node < MAX_NUMNODES; node++)
154 cpu_clear(cpu, node_to_cpumask_map[node]);
155 cpu_to_node_map[cpu] = 0;
157 #else /* !(CONFIG_NUMA && CONFIG_X86_32) */
158 #define map_cpu_to_node(cpu, node) ({})
159 #define unmap_cpu_to_node(cpu) ({})
163 static int boot_cpu_logical_apicid;
165 u8 cpu_2_logical_apicid[NR_CPUS] __read_mostly =
166 { [0 ... NR_CPUS-1] = BAD_APICID };
168 static void map_cpu_to_logical_apicid(void)
170 int cpu = smp_processor_id();
171 int apicid = logical_smp_processor_id();
172 int node = apicid_to_node(apicid);
174 if (!node_online(node))
175 node = first_online_node;
177 cpu_2_logical_apicid[cpu] = apicid;
178 map_cpu_to_node(cpu, node);
181 void numa_remove_cpu(int cpu)
183 cpu_2_logical_apicid[cpu] = BAD_APICID;
184 unmap_cpu_to_node(cpu);
187 #define map_cpu_to_logical_apicid() do {} while (0)
191 * Report back to the Boot Processor.
194 static void __cpuinit smp_callin(void)
197 unsigned long timeout;
200 * If waken up by an INIT in an 82489DX configuration
201 * we may get here before an INIT-deassert IPI reaches
202 * our local APIC. We have to wait for the IPI or we'll
203 * lock up on an APIC access.
205 wait_for_init_deassert(&init_deasserted);
208 * (This works even if the APIC is not enabled.)
210 phys_id = read_apic_id();
211 cpuid = smp_processor_id();
212 if (cpu_isset(cpuid, cpu_callin_map)) {
213 panic("%s: phys CPU#%d, CPU#%d already present??\n", __func__,
216 pr_debug("CPU#%d (phys ID: %d) waiting for CALLOUT\n", cpuid, phys_id);
219 * STARTUP IPIs are fragile beasts as they might sometimes
220 * trigger some glue motherboard logic. Complete APIC bus
221 * silence for 1 second, this overestimates the time the
222 * boot CPU is spending to send the up to 2 STARTUP IPIs
223 * by a factor of two. This should be enough.
227 * Waiting 2s total for startup (udelay is not yet working)
229 timeout = jiffies + 2*HZ;
230 while (time_before(jiffies, timeout)) {
232 * Has the boot CPU finished it's STARTUP sequence?
234 if (cpu_isset(cpuid, cpu_callout_map))
239 if (!time_before(jiffies, timeout)) {
240 panic("%s: CPU%d started up but did not get a callout!\n",
245 * the boot CPU has finished the init stage and is spinning
246 * on callin_map until we finish. We are free to set up this
247 * CPU, first the APIC. (this is probably redundant on most
251 pr_debug("CALLIN, before setup_local_APIC().\n");
252 smp_callin_clear_local_apic();
254 end_local_APIC_setup();
255 map_cpu_to_logical_apicid();
257 notify_cpu_starting(cpuid);
261 * Need to enable IRQs because it can take longer and then
262 * the NMI watchdog might kill us.
267 pr_debug("Stack at about %p\n", &cpuid);
270 * Save our processor parameters
272 smp_store_cpu_info(cpuid);
275 * Allow the master to continue.
277 cpu_set(cpuid, cpu_callin_map);
280 static int __cpuinitdata unsafe_smp;
283 * Activate a secondary processor.
285 notrace static void __cpuinit start_secondary(void *unused)
288 * Don't put *anything* before cpu_init(), SMP booting is too
289 * fragile that we want to limit the things done here to the
290 * most necessary things.
297 /* otherwise gcc will move up smp_processor_id before the cpu_init */
300 * Check TSC synchronization with the BP:
302 check_tsc_sync_target();
304 if (nmi_watchdog == NMI_IO_APIC) {
305 disable_8259A_irq(0);
306 enable_NMI_through_LVT0();
316 /* This must be done before setting cpu_online_map */
317 set_cpu_sibling_map(raw_smp_processor_id());
321 * We need to hold call_lock, so there is no inconsistency
322 * between the time smp_call_function() determines number of
323 * IPI recipients, and the time when the determination is made
324 * for which cpus receive the IPI. Holding this
325 * lock helps us to not include this cpu in a currently in progress
326 * smp_call_function().
328 * We need to hold vector_lock so there the set of online cpus
329 * does not change while we are assigning vectors to cpus. Holding
330 * this lock ensures we don't half assign or remove an irq from a cpu.
334 __setup_vector_irq(smp_processor_id());
335 cpu_set(smp_processor_id(), cpu_online_map);
336 unlock_vector_lock();
338 per_cpu(cpu_state, smp_processor_id()) = CPU_ONLINE;
340 /* enable local interrupts */
343 setup_secondary_clock();
349 static void __cpuinit smp_apply_quirks(struct cpuinfo_x86 *c)
352 * Mask B, Pentium, but not Pentium MMX
354 if (c->x86_vendor == X86_VENDOR_INTEL &&
356 c->x86_mask >= 1 && c->x86_mask <= 4 &&
359 * Remember we have B step Pentia with bugs
364 * Certain Athlons might work (for various values of 'work') in SMP
365 * but they are not certified as MP capable.
367 if ((c->x86_vendor == X86_VENDOR_AMD) && (c->x86 == 6)) {
369 if (num_possible_cpus() == 1)
372 /* Athlon 660/661 is valid. */
373 if ((c->x86_model == 6) && ((c->x86_mask == 0) ||
377 /* Duron 670 is valid */
378 if ((c->x86_model == 7) && (c->x86_mask == 0))
382 * Athlon 662, Duron 671, and Athlon >model 7 have capability
383 * bit. It's worth noting that the A5 stepping (662) of some
384 * Athlon XP's have the MP bit set.
385 * See http://www.heise.de/newsticker/data/jow-18.10.01-000 for
388 if (((c->x86_model == 6) && (c->x86_mask >= 2)) ||
389 ((c->x86_model == 7) && (c->x86_mask >= 1)) ||
394 /* If we get here, not a certified SMP capable AMD system. */
402 static void __cpuinit smp_checks(void)
405 printk(KERN_WARNING "WARNING: SMP operation may be unreliable"
406 "with B stepping processors.\n");
409 * Don't taint if we are running SMP kernel on a single non-MP
412 if (unsafe_smp && num_online_cpus() > 1) {
413 printk(KERN_INFO "WARNING: This combination of AMD"
414 "processors is not suitable for SMP.\n");
415 add_taint(TAINT_UNSAFE_SMP);
420 * The bootstrap kernel entry code has set these up. Save them for
424 void __cpuinit smp_store_cpu_info(int id)
426 struct cpuinfo_x86 *c = &cpu_data(id);
431 identify_secondary_cpu(c);
436 void __cpuinit set_cpu_sibling_map(int cpu)
439 struct cpuinfo_x86 *c = &cpu_data(cpu);
441 cpu_set(cpu, cpu_sibling_setup_map);
443 if (smp_num_siblings > 1) {
444 for_each_cpu_mask_nr(i, cpu_sibling_setup_map) {
445 if (c->phys_proc_id == cpu_data(i).phys_proc_id &&
446 c->cpu_core_id == cpu_data(i).cpu_core_id) {
447 cpu_set(i, per_cpu(cpu_sibling_map, cpu));
448 cpu_set(cpu, per_cpu(cpu_sibling_map, i));
449 cpu_set(i, per_cpu(cpu_core_map, cpu));
450 cpu_set(cpu, per_cpu(cpu_core_map, i));
451 cpu_set(i, c->llc_shared_map);
452 cpu_set(cpu, cpu_data(i).llc_shared_map);
456 cpu_set(cpu, per_cpu(cpu_sibling_map, cpu));
459 cpu_set(cpu, c->llc_shared_map);
461 if (current_cpu_data.x86_max_cores == 1) {
462 per_cpu(cpu_core_map, cpu) = per_cpu(cpu_sibling_map, cpu);
467 for_each_cpu_mask_nr(i, cpu_sibling_setup_map) {
468 if (per_cpu(cpu_llc_id, cpu) != BAD_APICID &&
469 per_cpu(cpu_llc_id, cpu) == per_cpu(cpu_llc_id, i)) {
470 cpu_set(i, c->llc_shared_map);
471 cpu_set(cpu, cpu_data(i).llc_shared_map);
473 if (c->phys_proc_id == cpu_data(i).phys_proc_id) {
474 cpu_set(i, per_cpu(cpu_core_map, cpu));
475 cpu_set(cpu, per_cpu(cpu_core_map, i));
477 * Does this new cpu bringup a new core?
479 if (cpus_weight(per_cpu(cpu_sibling_map, cpu)) == 1) {
481 * for each core in package, increment
482 * the booted_cores for this new cpu
484 if (first_cpu(per_cpu(cpu_sibling_map, i)) == i)
487 * increment the core count for all
488 * the other cpus in this package
491 cpu_data(i).booted_cores++;
492 } else if (i != cpu && !c->booted_cores)
493 c->booted_cores = cpu_data(i).booted_cores;
498 /* maps the cpu to the sched domain representing multi-core */
499 const struct cpumask *cpu_coregroup_mask(int cpu)
501 struct cpuinfo_x86 *c = &cpu_data(cpu);
503 * For perf, we return last level cache shared map.
504 * And for power savings, we return cpu_core_map
506 if (sched_mc_power_savings || sched_smt_power_savings)
507 return &per_cpu(cpu_core_map, cpu);
509 return &c->llc_shared_map;
512 cpumask_t cpu_coregroup_map(int cpu)
514 return *cpu_coregroup_mask(cpu);
517 static void impress_friends(void)
520 unsigned long bogosum = 0;
522 * Allow the user to impress friends.
524 pr_debug("Before bogomips.\n");
525 for_each_possible_cpu(cpu)
526 if (cpu_isset(cpu, cpu_callout_map))
527 bogosum += cpu_data(cpu).loops_per_jiffy;
529 "Total of %d processors activated (%lu.%02lu BogoMIPS).\n",
532 (bogosum/(5000/HZ))%100);
534 pr_debug("Before bogocount - setting activated=1.\n");
537 void __inquire_remote_apic(int apicid)
539 unsigned i, regs[] = { APIC_ID >> 4, APIC_LVR >> 4, APIC_SPIV >> 4 };
540 char *names[] = { "ID", "VERSION", "SPIV" };
544 printk(KERN_INFO "Inquiring remote APIC 0x%x...\n", apicid);
546 for (i = 0; i < ARRAY_SIZE(regs); i++) {
547 printk(KERN_INFO "... APIC 0x%x %s: ", apicid, names[i]);
552 status = safe_apic_wait_icr_idle();
555 "a previous APIC delivery may have failed\n");
557 apic_icr_write(APIC_DM_REMRD | regs[i], apicid);
562 status = apic_read(APIC_ICR) & APIC_ICR_RR_MASK;
563 } while (status == APIC_ICR_RR_INPROG && timeout++ < 1000);
566 case APIC_ICR_RR_VALID:
567 status = apic_read(APIC_RRR);
568 printk(KERN_CONT "%08x\n", status);
571 printk(KERN_CONT "failed\n");
577 * Poke the other CPU in the eye via NMI to wake it up. Remember that the normal
578 * INIT, INIT, STARTUP sequence will reset the chip hard for us, and this
579 * won't ... remember to clear down the APIC, etc later.
582 wakeup_secondary_cpu_via_nmi(int logical_apicid, unsigned long start_eip)
584 unsigned long send_status, accept_status = 0;
588 /* Boot on the stack */
589 /* Kick the second */
590 apic_icr_write(APIC_DM_NMI | APIC_DEST_LOGICAL, logical_apicid);
592 pr_debug("Waiting for send to finish...\n");
593 send_status = safe_apic_wait_icr_idle();
596 * Give the other CPU some time to accept the IPI.
599 if (APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid])) {
600 maxlvt = lapic_get_maxlvt();
601 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
602 apic_write(APIC_ESR, 0);
603 accept_status = (apic_read(APIC_ESR) & 0xEF);
605 pr_debug("NMI sent.\n");
608 printk(KERN_ERR "APIC never delivered???\n");
610 printk(KERN_ERR "APIC delivery error (%lx).\n", accept_status);
612 return (send_status | accept_status);
616 wakeup_secondary_cpu_via_init(int phys_apicid, unsigned long start_eip)
618 unsigned long send_status, accept_status = 0;
619 int maxlvt, num_starts, j;
621 if (get_uv_system_type() == UV_NON_UNIQUE_APIC) {
622 send_status = uv_wakeup_secondary(phys_apicid, start_eip);
623 atomic_set(&init_deasserted, 1);
627 maxlvt = lapic_get_maxlvt();
630 * Be paranoid about clearing APIC errors.
632 if (APIC_INTEGRATED(apic_version[phys_apicid])) {
633 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
634 apic_write(APIC_ESR, 0);
638 pr_debug("Asserting INIT.\n");
641 * Turn INIT on target chip
646 apic_icr_write(APIC_INT_LEVELTRIG | APIC_INT_ASSERT | APIC_DM_INIT,
649 pr_debug("Waiting for send to finish...\n");
650 send_status = safe_apic_wait_icr_idle();
654 pr_debug("Deasserting INIT.\n");
658 apic_icr_write(APIC_INT_LEVELTRIG | APIC_DM_INIT, phys_apicid);
660 pr_debug("Waiting for send to finish...\n");
661 send_status = safe_apic_wait_icr_idle();
664 atomic_set(&init_deasserted, 1);
667 * Should we send STARTUP IPIs ?
669 * Determine this based on the APIC version.
670 * If we don't have an integrated APIC, don't send the STARTUP IPIs.
672 if (APIC_INTEGRATED(apic_version[phys_apicid]))
678 * Paravirt / VMI wants a startup IPI hook here to set up the
679 * target processor state.
681 startup_ipi_hook(phys_apicid, (unsigned long) start_secondary,
682 (unsigned long)stack_start.sp);
685 * Run STARTUP IPI loop.
687 pr_debug("#startup loops: %d.\n", num_starts);
689 for (j = 1; j <= num_starts; j++) {
690 pr_debug("Sending STARTUP #%d.\n", j);
691 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
692 apic_write(APIC_ESR, 0);
694 pr_debug("After apic_write.\n");
701 /* Boot on the stack */
702 /* Kick the second */
703 apic_icr_write(APIC_DM_STARTUP | (start_eip >> 12),
707 * Give the other CPU some time to accept the IPI.
711 pr_debug("Startup point 1.\n");
713 pr_debug("Waiting for send to finish...\n");
714 send_status = safe_apic_wait_icr_idle();
717 * Give the other CPU some time to accept the IPI.
720 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
721 apic_write(APIC_ESR, 0);
722 accept_status = (apic_read(APIC_ESR) & 0xEF);
723 if (send_status || accept_status)
726 pr_debug("After Startup.\n");
729 printk(KERN_ERR "APIC never delivered???\n");
731 printk(KERN_ERR "APIC delivery error (%lx).\n", accept_status);
733 return (send_status | accept_status);
737 struct work_struct work;
738 struct task_struct *idle;
739 struct completion done;
743 static void __cpuinit do_fork_idle(struct work_struct *work)
745 struct create_idle *c_idle =
746 container_of(work, struct create_idle, work);
748 c_idle->idle = fork_idle(c_idle->cpu);
749 complete(&c_idle->done);
754 /* __ref because it's safe to call free_bootmem when after_bootmem == 0. */
755 static void __ref free_bootmem_pda(struct x8664_pda *oldpda)
758 free_bootmem((unsigned long)oldpda, sizeof(*oldpda));
762 * Allocate node local memory for the AP pda.
764 * Must be called after the _cpu_pda pointer table is initialized.
766 int __cpuinit get_local_pda(int cpu)
768 struct x8664_pda *oldpda, *newpda;
769 unsigned long size = sizeof(struct x8664_pda);
770 int node = cpu_to_node(cpu);
772 if (cpu_pda(cpu) && !cpu_pda(cpu)->in_bootmem)
775 oldpda = cpu_pda(cpu);
776 newpda = kmalloc_node(size, GFP_ATOMIC, node);
778 printk(KERN_ERR "Could not allocate node local PDA "
779 "for CPU %d on node %d\n", cpu, node);
782 return 0; /* have a usable pda */
788 memcpy(newpda, oldpda, size);
789 free_bootmem_pda(oldpda);
792 newpda->in_bootmem = 0;
793 cpu_pda(cpu) = newpda;
796 #endif /* CONFIG_X86_64 */
798 static int __cpuinit do_boot_cpu(int apicid, int cpu)
800 * NOTE - on most systems this is a PHYSICAL apic ID, but on multiquad
801 * (ie clustered apic addressing mode), this is a LOGICAL apic ID.
802 * Returns zero if CPU booted OK, else error code from wakeup_secondary_cpu.
805 unsigned long boot_error = 0;
807 unsigned long start_ip;
808 unsigned short nmi_high = 0, nmi_low = 0;
809 struct create_idle c_idle = {
811 .done = COMPLETION_INITIALIZER_ONSTACK(c_idle.done),
813 INIT_WORK(&c_idle.work, do_fork_idle);
816 /* Allocate node local memory for AP pdas */
818 boot_error = get_local_pda(cpu);
821 /* if can't get pda memory, can't start cpu */
825 alternatives_smp_switch(1);
827 c_idle.idle = get_idle_for_cpu(cpu);
830 * We can't use kernel_thread since we must avoid to
831 * reschedule the child.
834 c_idle.idle->thread.sp = (unsigned long) (((struct pt_regs *)
835 (THREAD_SIZE + task_stack_page(c_idle.idle))) - 1);
836 init_idle(c_idle.idle, cpu);
840 if (!keventd_up() || current_is_keventd())
841 c_idle.work.func(&c_idle.work);
843 schedule_work(&c_idle.work);
844 wait_for_completion(&c_idle.done);
847 if (IS_ERR(c_idle.idle)) {
848 printk("failed fork for CPU %d\n", cpu);
849 return PTR_ERR(c_idle.idle);
852 set_idle_for_cpu(cpu, c_idle.idle);
855 per_cpu(current_task, cpu) = c_idle.idle;
857 /* Stack for startup_32 can be just as for start_secondary onwards */
860 cpu_pda(cpu)->pcurrent = c_idle.idle;
861 clear_tsk_thread_flag(c_idle.idle, TIF_FORK);
863 early_gdt_descr.address = (unsigned long)get_cpu_gdt_table(cpu);
864 initial_code = (unsigned long)start_secondary;
865 stack_start.sp = (void *) c_idle.idle->thread.sp;
867 /* start_ip had better be page-aligned! */
868 start_ip = setup_trampoline();
870 /* So we see what's up */
871 printk(KERN_INFO "Booting processor %d APIC 0x%x ip 0x%lx\n",
872 cpu, apicid, start_ip);
875 * This grunge runs the startup process for
876 * the targeted processor.
879 atomic_set(&init_deasserted, 0);
881 if (get_uv_system_type() != UV_NON_UNIQUE_APIC) {
883 pr_debug("Setting warm reset code and vector.\n");
885 store_NMI_vector(&nmi_high, &nmi_low);
887 smpboot_setup_warm_reset_vector(start_ip);
889 * Be paranoid about clearing APIC errors.
891 if (APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid])) {
892 apic_write(APIC_ESR, 0);
898 * Starting actual IPI sequence...
900 boot_error = wakeup_secondary_cpu(apicid, start_ip);
904 * allow APs to start initializing.
906 pr_debug("Before Callout %d.\n", cpu);
907 cpu_set(cpu, cpu_callout_map);
908 pr_debug("After Callout %d.\n", cpu);
911 * Wait 5s total for a response
913 for (timeout = 0; timeout < 50000; timeout++) {
914 if (cpu_isset(cpu, cpu_callin_map))
915 break; /* It has booted */
919 if (cpu_isset(cpu, cpu_callin_map)) {
920 /* number CPUs logically, starting from 1 (BSP is 0) */
922 printk(KERN_INFO "CPU%d: ", cpu);
923 print_cpu_info(&cpu_data(cpu));
924 pr_debug("CPU has booted.\n");
927 if (*((volatile unsigned char *)trampoline_base)
929 /* trampoline started but...? */
930 printk(KERN_ERR "Stuck ??\n");
932 /* trampoline code not run */
933 printk(KERN_ERR "Not responding.\n");
934 if (get_uv_system_type() != UV_NON_UNIQUE_APIC)
935 inquire_remote_apic(apicid);
942 /* Try to put things back the way they were before ... */
943 numa_remove_cpu(cpu); /* was set by numa_add_cpu */
944 cpu_clear(cpu, cpu_callout_map); /* was set by do_boot_cpu() */
945 cpu_clear(cpu, cpu_initialized); /* was set by cpu_init() */
946 cpu_clear(cpu, cpu_present_map);
947 per_cpu(x86_cpu_to_apicid, cpu) = BAD_APICID;
950 /* mark "stuck" area as not stuck */
951 *((volatile unsigned long *)trampoline_base) = 0;
954 * Cleanup possible dangling ends...
956 smpboot_restore_warm_reset_vector();
961 int __cpuinit native_cpu_up(unsigned int cpu)
963 int apicid = cpu_present_to_apicid(cpu);
967 WARN_ON(irqs_disabled());
969 pr_debug("++++++++++++++++++++=_---CPU UP %u\n", cpu);
971 if (apicid == BAD_APICID || apicid == boot_cpu_physical_apicid ||
972 !physid_isset(apicid, phys_cpu_present_map)) {
973 printk(KERN_ERR "%s: bad cpu %d\n", __func__, cpu);
978 * Already booted CPU?
980 if (cpu_isset(cpu, cpu_callin_map)) {
981 pr_debug("do_boot_cpu %d Already started\n", cpu);
986 * Save current MTRR state in case it was changed since early boot
987 * (e.g. by the ACPI SMI) to initialize new CPUs with MTRRs in sync:
991 per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
994 /* init low mem mapping */
995 clone_pgd_range(swapper_pg_dir, swapper_pg_dir + KERNEL_PGD_BOUNDARY,
996 min_t(unsigned long, KERNEL_PGD_PTRS, KERNEL_PGD_BOUNDARY));
1000 err = do_boot_cpu(apicid, cpu);
1005 err = do_boot_cpu(apicid, cpu);
1008 pr_debug("do_boot_cpu failed %d\n", err);
1013 * Check TSC synchronization with the AP (keep irqs disabled
1016 local_irq_save(flags);
1017 check_tsc_sync_source(cpu);
1018 local_irq_restore(flags);
1020 while (!cpu_online(cpu)) {
1022 touch_nmi_watchdog();
1029 * Fall back to non SMP mode after errors.
1031 * RED-PEN audit/test this more. I bet there is more state messed up here.
1033 static __init void disable_smp(void)
1035 cpu_present_map = cpumask_of_cpu(0);
1036 cpu_possible_map = cpumask_of_cpu(0);
1037 smpboot_clear_io_apic_irqs();
1039 if (smp_found_config)
1040 physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map);
1042 physid_set_mask_of_physid(0, &phys_cpu_present_map);
1043 map_cpu_to_logical_apicid();
1044 cpu_set(0, per_cpu(cpu_sibling_map, 0));
1045 cpu_set(0, per_cpu(cpu_core_map, 0));
1049 * Various sanity checks.
1051 static int __init smp_sanity_check(unsigned max_cpus)
1055 #if defined(CONFIG_X86_PC) && defined(CONFIG_X86_32)
1056 if (def_to_bigsmp && nr_cpu_ids > 8) {
1061 "More than 8 CPUs detected - skipping them.\n"
1062 "Use CONFIG_X86_GENERICARCH and CONFIG_X86_BIGSMP.\n");
1065 for_each_present_cpu(cpu) {
1067 cpu_clear(cpu, cpu_present_map);
1072 for_each_possible_cpu(cpu) {
1074 cpu_clear(cpu, cpu_possible_map);
1082 if (!physid_isset(hard_smp_processor_id(), phys_cpu_present_map)) {
1084 "weird, boot CPU (#%d) not listed by the BIOS.\n",
1085 hard_smp_processor_id());
1087 physid_set(hard_smp_processor_id(), phys_cpu_present_map);
1091 * If we couldn't find an SMP configuration at boot time,
1092 * get out of here now!
1094 if (!smp_found_config && !acpi_lapic) {
1096 printk(KERN_NOTICE "SMP motherboard not detected.\n");
1098 if (APIC_init_uniprocessor())
1099 printk(KERN_NOTICE "Local APIC not detected."
1100 " Using dummy APIC emulation.\n");
1105 * Should not be necessary because the MP table should list the boot
1106 * CPU too, but we do it for the sake of robustness anyway.
1108 if (!check_phys_apicid_present(boot_cpu_physical_apicid)) {
1110 "weird, boot CPU (#%d) not listed by the BIOS.\n",
1111 boot_cpu_physical_apicid);
1112 physid_set(hard_smp_processor_id(), phys_cpu_present_map);
1117 * If we couldn't find a local APIC, then get out of here now!
1119 if (APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid]) &&
1121 printk(KERN_ERR "BIOS bug, local APIC #%d not detected!...\n",
1122 boot_cpu_physical_apicid);
1123 printk(KERN_ERR "... forcing use of dummy APIC emulation."
1124 "(tell your hw vendor)\n");
1125 smpboot_clear_io_apic();
1129 verify_local_APIC();
1132 * If SMP should be disabled, then really disable it!
1135 printk(KERN_INFO "SMP mode deactivated.\n");
1136 smpboot_clear_io_apic();
1138 localise_nmi_watchdog();
1142 end_local_APIC_setup();
1149 static void __init smp_cpu_index_default(void)
1152 struct cpuinfo_x86 *c;
1154 for_each_possible_cpu(i) {
1156 /* mark all to hotplug */
1157 c->cpu_index = NR_CPUS;
1162 * Prepare for SMP bootup. The MP table or ACPI has been read
1163 * earlier. Just do some sanity checking here and enable APIC mode.
1165 void __init native_smp_prepare_cpus(unsigned int max_cpus)
1168 smp_cpu_index_default();
1169 current_cpu_data = boot_cpu_data;
1170 cpu_callin_map = cpumask_of_cpu(0);
1173 * Setup boot CPU information
1175 smp_store_cpu_info(0); /* Final full version of the data */
1176 #ifdef CONFIG_X86_32
1177 boot_cpu_logical_apicid = logical_smp_processor_id();
1179 current_thread_info()->cpu = 0; /* needed? */
1180 set_cpu_sibling_map(0);
1182 #ifdef CONFIG_X86_64
1184 setup_apic_routing();
1187 if (smp_sanity_check(max_cpus) < 0) {
1188 printk(KERN_INFO "SMP disabled\n");
1194 if (read_apic_id() != boot_cpu_physical_apicid) {
1195 panic("Boot APIC ID in local APIC unexpected (%d vs %d)",
1196 read_apic_id(), boot_cpu_physical_apicid);
1197 /* Or can we switch back to PIC here? */
1204 * Switch from PIC to APIC mode.
1208 #ifdef CONFIG_X86_64
1210 * Enable IO APIC before setting up error vector
1212 if (!skip_ioapic_setup && nr_ioapics)
1215 end_local_APIC_setup();
1217 map_cpu_to_logical_apicid();
1219 setup_portio_remap();
1221 smpboot_setup_io_apic();
1223 * Set up local APIC timer on boot CPU.
1226 printk(KERN_INFO "CPU%d: ", 0);
1227 print_cpu_info(&cpu_data(0));
1236 * Early setup to make printk work.
1238 void __init native_smp_prepare_boot_cpu(void)
1240 int me = smp_processor_id();
1241 #ifdef CONFIG_X86_32
1244 switch_to_new_gdt();
1245 /* already set me in cpu_online_map in boot_cpu_init() */
1246 cpu_set(me, cpu_callout_map);
1247 per_cpu(cpu_state, me) = CPU_ONLINE;
1250 void __init native_smp_cpus_done(unsigned int max_cpus)
1252 pr_debug("Boot done.\n");
1256 #ifdef CONFIG_X86_IO_APIC
1257 setup_ioapic_dest();
1259 check_nmi_watchdog();
1262 static int __initdata setup_possible_cpus = -1;
1263 static int __init _setup_possible_cpus(char *str)
1265 get_option(&str, &setup_possible_cpus);
1268 early_param("possible_cpus", _setup_possible_cpus);
1272 * cpu_possible_map should be static, it cannot change as cpu's
1273 * are onlined, or offlined. The reason is per-cpu data-structures
1274 * are allocated by some modules at init time, and dont expect to
1275 * do this dynamically on cpu arrival/departure.
1276 * cpu_present_map on the other hand can change dynamically.
1277 * In case when cpu_hotplug is not compiled, then we resort to current
1278 * behaviour, which is cpu_possible == cpu_present.
1281 * Three ways to find out the number of additional hotplug CPUs:
1282 * - If the BIOS specified disabled CPUs in ACPI/mptables use that.
1283 * - The user can overwrite it with possible_cpus=NUM
1284 * - Otherwise don't reserve additional CPUs.
1285 * We do this because additional CPUs waste a lot of memory.
1288 __init void prefill_possible_map(void)
1292 /* no processor from mptable or madt */
1293 if (!num_processors)
1296 if (setup_possible_cpus == -1)
1297 possible = num_processors + disabled_cpus;
1299 possible = setup_possible_cpus;
1301 if (possible > CONFIG_NR_CPUS) {
1303 "%d Processors exceeds NR_CPUS limit of %d\n",
1304 possible, CONFIG_NR_CPUS);
1305 possible = CONFIG_NR_CPUS;
1308 printk(KERN_INFO "SMP: Allowing %d CPUs, %d hotplug CPUs\n",
1309 possible, max_t(int, possible - num_processors, 0));
1311 for (i = 0; i < possible; i++)
1312 cpu_set(i, cpu_possible_map);
1314 nr_cpu_ids = possible;
1317 #ifdef CONFIG_HOTPLUG_CPU
1319 static void remove_siblinginfo(int cpu)
1322 struct cpuinfo_x86 *c = &cpu_data(cpu);
1324 for_each_cpu_mask_nr(sibling, per_cpu(cpu_core_map, cpu)) {
1325 cpu_clear(cpu, per_cpu(cpu_core_map, sibling));
1327 * last thread sibling in this cpu core going down
1329 if (cpus_weight(per_cpu(cpu_sibling_map, cpu)) == 1)
1330 cpu_data(sibling).booted_cores--;
1333 for_each_cpu_mask_nr(sibling, per_cpu(cpu_sibling_map, cpu))
1334 cpu_clear(cpu, per_cpu(cpu_sibling_map, sibling));
1335 cpus_clear(per_cpu(cpu_sibling_map, cpu));
1336 cpus_clear(per_cpu(cpu_core_map, cpu));
1337 c->phys_proc_id = 0;
1339 cpu_clear(cpu, cpu_sibling_setup_map);
1342 static void __ref remove_cpu_from_maps(int cpu)
1344 cpu_clear(cpu, cpu_online_map);
1345 cpu_clear(cpu, cpu_callout_map);
1346 cpu_clear(cpu, cpu_callin_map);
1347 /* was set by cpu_init() */
1348 cpu_clear(cpu, cpu_initialized);
1349 numa_remove_cpu(cpu);
1352 void cpu_disable_common(void)
1354 int cpu = smp_processor_id();
1357 * Allow any queued timer interrupts to get serviced
1358 * This is only a temporary solution until we cleanup
1359 * fixup_irqs as we do for IA64.
1364 local_irq_disable();
1365 remove_siblinginfo(cpu);
1367 /* It's now safe to remove this processor from the online map */
1369 remove_cpu_from_maps(cpu);
1370 unlock_vector_lock();
1374 int native_cpu_disable(void)
1376 int cpu = smp_processor_id();
1379 * Perhaps use cpufreq to drop frequency, but that could go
1380 * into generic code.
1382 * We won't take down the boot processor on i386 due to some
1383 * interrupts only being able to be serviced by the BSP.
1384 * Especially so if we're not using an IOAPIC -zwane
1389 if (nmi_watchdog == NMI_LOCAL_APIC)
1390 stop_apic_nmi_watchdog(NULL);
1393 cpu_disable_common();
1397 void native_cpu_die(unsigned int cpu)
1399 /* We don't do anything here: idle task is faking death itself. */
1402 for (i = 0; i < 10; i++) {
1403 /* They ack this in play_dead by setting CPU_DEAD */
1404 if (per_cpu(cpu_state, cpu) == CPU_DEAD) {
1405 printk(KERN_INFO "CPU %d is now offline\n", cpu);
1406 if (1 == num_online_cpus())
1407 alternatives_smp_switch(0);
1412 printk(KERN_ERR "CPU %u didn't die...\n", cpu);
1415 void play_dead_common(void)
1418 reset_lazy_tlbstate();
1419 irq_ctx_exit(raw_smp_processor_id());
1420 c1e_remove_cpu(raw_smp_processor_id());
1424 __get_cpu_var(cpu_state) = CPU_DEAD;
1427 * With physical CPU hotplug, we should halt the cpu
1429 local_irq_disable();
1432 void native_play_dead(void)
1438 #else /* ... !CONFIG_HOTPLUG_CPU */
1439 int native_cpu_disable(void)
1444 void native_cpu_die(unsigned int cpu)
1446 /* We said "no" in __cpu_disable */
1450 void native_play_dead(void)