git.oblomov.eu Git - linux-2.6/blob - arch/ia64/kernel/smpboot.c

   1 /*
   2  * SMP boot-related support
   3  *
   4  * Copyright (C) 1998-2003, 2005 Hewlett-Packard Co
   5  *      David Mosberger-Tang <davidm@hpl.hp.com>
   6  * Copyright (C) 2001, 2004-2005 Intel Corp
   7  *      Rohit Seth <rohit.seth@intel.com>
   8  *      Suresh Siddha <suresh.b.siddha@intel.com>
   9  *      Gordon Jin <gordon.jin@intel.com>
  10  *      Ashok Raj  <ashok.raj@intel.com>
  11  *
  12  * 01/05/16 Rohit Seth <rohit.seth@intel.com>   Moved SMP booting functions from smp.c to here.
  13  * 01/04/27 David Mosberger <davidm@hpl.hp.com> Added ITC synching code.
  14  * 02/07/31 David Mosberger <davidm@hpl.hp.com> Switch over to hotplug-CPU boot-sequence.
  15  *                                              smp_boot_cpus()/smp_commence() is replaced by
  16  *                                              smp_prepare_cpus()/__cpu_up()/smp_cpus_done().
  17  * 04/06/21 Ashok Raj           <ashok.raj@intel.com> Added CPU Hotplug Support
  18  * 04/12/26 Jin Gordon <gordon.jin@intel.com>
  19  * 04/12/26 Rohit Seth <rohit.seth@intel.com>
  20  *                                              Add multi-threading and multi-core detection
  21  * 05/01/30 Suresh Siddha <suresh.b.siddha@intel.com>
  22  *                                              Setup cpu_sibling_map and cpu_core_map
  23  */
  24 #include <linux/config.h>
  25
  26 #include <linux/module.h>
  27 #include <linux/acpi.h>
  28 #include <linux/bootmem.h>
  29 #include <linux/cpu.h>
  30 #include <linux/delay.h>
  31 #include <linux/init.h>
  32 #include <linux/interrupt.h>
  33 #include <linux/irq.h>
  34 #include <linux/kernel.h>
  35 #include <linux/kernel_stat.h>
  36 #include <linux/mm.h>
  37 #include <linux/notifier.h>
  38 #include <linux/smp.h>
  39 #include <linux/smp_lock.h>
  40 #include <linux/spinlock.h>
  41 #include <linux/efi.h>
  42 #include <linux/percpu.h>
  43 #include <linux/bitops.h>
  44
  45 #include <asm/atomic.h>
  46 #include <asm/cache.h>
  47 #include <asm/current.h>
  48 #include <asm/delay.h>
  49 #include <asm/ia32.h>
  50 #include <asm/io.h>
  51 #include <asm/irq.h>
  52 #include <asm/machvec.h>
  53 #include <asm/mca.h>
  54 #include <asm/page.h>
  55 #include <asm/pgalloc.h>
  56 #include <asm/pgtable.h>
  57 #include <asm/processor.h>
  58 #include <asm/ptrace.h>
  59 #include <asm/sal.h>
  60 #include <asm/system.h>
  61 #include <asm/tlbflush.h>
  62 #include <asm/unistd.h>
  63
  64 #define SMP_DEBUG 0
  65
  66 #if SMP_DEBUG
  67 #define Dprintk(x...)  printk(x)
  68 #else
  69 #define Dprintk(x...)
  70 #endif
  71
  72 #ifdef CONFIG_HOTPLUG_CPU
  73 /*
  74  * Store all idle threads, this can be reused instead of creating
  75  * a new thread. Also avoids complicated thread destroy functionality
  76  * for idle threads.
  77  */
  78 struct task_struct *idle_thread_array[NR_CPUS];
  79
  80 /*
  81  * Global array allocated for NR_CPUS at boot time
  82  */
  83 struct sal_to_os_boot sal_boot_rendez_state[NR_CPUS];
  84
  85 /*
  86  * start_ap in head.S uses this to store current booting cpu
  87  * info.
  88  */
  89 struct sal_to_os_boot *sal_state_for_booting_cpu = &sal_boot_rendez_state[0];
  90
  91 #define set_brendez_area(x) (sal_state_for_booting_cpu = &sal_boot_rendez_state[(x)]);
  92
  93 #define get_idle_for_cpu(x)             (idle_thread_array[(x)])
  94 #define set_idle_for_cpu(x,p)   (idle_thread_array[(x)] = (p))
  95
  96 #else
  97
  98 #define get_idle_for_cpu(x)             (NULL)
  99 #define set_idle_for_cpu(x,p)
 100 #define set_brendez_area(x)
 101 #endif
 102
 103
 104 /*
 105  * ITC synchronization related stuff:
 106  */
 107 #define MASTER  0
 108 #define SLAVE   (SMP_CACHE_BYTES/8)
 109
 110 #define NUM_ROUNDS      64      /* magic value */
 111 #define NUM_ITERS       5       /* likewise */
 112
 113 static DEFINE_SPINLOCK(itc_sync_lock);
 114 static volatile unsigned long go[SLAVE + 1];
 115
 116 #define DEBUG_ITC_SYNC  0
 117
 118 extern void __devinit calibrate_delay (void);
 119 extern void start_ap (void);
 120 extern unsigned long ia64_iobase;
 121
 122 task_t *task_for_booting_cpu;
 123
 124 /*
 125  * State for each CPU
 126  */
 127 DEFINE_PER_CPU(int, cpu_state);
 128
 129 /* Bitmasks of currently online, and possible CPUs */
 130 cpumask_t cpu_online_map;
 131 EXPORT_SYMBOL(cpu_online_map);
 132 cpumask_t cpu_possible_map;
 133 EXPORT_SYMBOL(cpu_possible_map);
 134
 135 cpumask_t cpu_core_map[NR_CPUS] __cacheline_aligned;
 136 cpumask_t cpu_sibling_map[NR_CPUS] __cacheline_aligned;
 137 int smp_num_siblings = 1;
 138 int smp_num_cpucores = 1;
 139
 140 /* which logical CPU number maps to which CPU (physical APIC ID) */
 141 volatile int ia64_cpu_to_sapicid[NR_CPUS];
 142 EXPORT_SYMBOL(ia64_cpu_to_sapicid);
 143
 144 static volatile cpumask_t cpu_callin_map;
 145
 146 struct smp_boot_data smp_boot_data __initdata;
 147
 148 unsigned long ap_wakeup_vector = -1; /* External Int use to wakeup APs */
 149
 150 char __initdata no_int_routing;
 151
 152 unsigned char smp_int_redirect; /* are INT and IPI redirectable by the chipset? */
 153
 154 static int __init
 155 nointroute (char *str)
 156 {
 157         no_int_routing = 1;
 158         printk ("no_int_routing on\n");
 159         return 1;
 160 }
 161
 162 __setup("nointroute", nointroute);
 163
 164 void
 165 sync_master (void *arg)
 166 {
 167         unsigned long flags, i;
 168
 169         go[MASTER] = 0;
 170
 171         local_irq_save(flags);
 172         {
 173                 for (i = 0; i < NUM_ROUNDS*NUM_ITERS; ++i) {
 174                         while (!go[MASTER])
 175                                 cpu_relax();
 176                         go[MASTER] = 0;
 177                         go[SLAVE] = ia64_get_itc();
 178                 }
 179         }
 180         local_irq_restore(flags);
 181 }
 182
 183 /*
 184  * Return the number of cycles by which our itc differs from the itc on the master
 185  * (time-keeper) CPU.  A positive number indicates our itc is ahead of the master,
 186  * negative that it is behind.
 187  */
 188 static inline long
 189 get_delta (long *rt, long *master)
 190 {
 191         unsigned long best_t0 = 0, best_t1 = ~0UL, best_tm = 0;
 192         unsigned long tcenter, t0, t1, tm;
 193         long i;
 194
 195         for (i = 0; i < NUM_ITERS; ++i) {
 196                 t0 = ia64_get_itc();
 197                 go[MASTER] = 1;
 198                 while (!(tm = go[SLAVE]))
 199                         cpu_relax();
 200                 go[SLAVE] = 0;
 201                 t1 = ia64_get_itc();
 202
 203                 if (t1 - t0 < best_t1 - best_t0)
 204                         best_t0 = t0, best_t1 = t1, best_tm = tm;
 205         }
 206
 207         *rt = best_t1 - best_t0;
 208         *master = best_tm - best_t0;
 209
 210         /* average best_t0 and best_t1 without overflow: */
 211         tcenter = (best_t0/2 + best_t1/2);
 212         if (best_t0 % 2 + best_t1 % 2 == 2)
 213                 ++tcenter;
 214         return tcenter - best_tm;
 215 }
 216
 217 /*
 218  * Synchronize ar.itc of the current (slave) CPU with the ar.itc of the MASTER CPU
 219  * (normally the time-keeper CPU).  We use a closed loop to eliminate the possibility of
 220  * unaccounted-for errors (such as getting a machine check in the middle of a calibration
 221  * step).  The basic idea is for the slave to ask the master what itc value it has and to
 222  * read its own itc before and after the master responds.  Each iteration gives us three
 223  * timestamps:
 224  *
 225  *      slave           master
 226  *
 227  *      t0 ---\
 228  *             ---\
 229  *                 --->
 230  *                      tm
 231  *                 /---
 232  *             /---
 233  *      t1 <---
 234  *
 235  *
 236  * The goal is to adjust the slave's ar.itc such that tm falls exactly half-way between t0
 237  * and t1.  If we achieve this, the clocks are synchronized provided the interconnect
 238  * between the slave and the master is symmetric.  Even if the interconnect were
 239  * asymmetric, we would still know that the synchronization error is smaller than the
 240  * roundtrip latency (t0 - t1).
 241  *
 242  * When the interconnect is quiet and symmetric, this lets us synchronize the itc to
 243  * within one or two cycles.  However, we can only *guarantee* that the synchronization is
 244  * accurate to within a round-trip time, which is typically in the range of several
 245  * hundred cycles (e.g., ~500 cycles).  In practice, this means that the itc's are usually
 246  * almost perfectly synchronized, but we shouldn't assume that the accuracy is much better
 247  * than half a micro second or so.
 248  */
 249 void
 250 ia64_sync_itc (unsigned int master)
 251 {
 252         long i, delta, adj, adjust_latency = 0, done = 0;
 253         unsigned long flags, rt, master_time_stamp, bound;
 254 #if DEBUG_ITC_SYNC
 255         struct {
 256                 long rt;        /* roundtrip time */
 257                 long master;    /* master's timestamp */
 258                 long diff;      /* difference between midpoint and master's timestamp */
 259                 long lat;       /* estimate of itc adjustment latency */
 260         } t[NUM_ROUNDS];
 261 #endif
 262
 263         /*
 264          * Make sure local timer ticks are disabled while we sync.  If
 265          * they were enabled, we'd have to worry about nasty issues
 266          * like setting the ITC ahead of (or a long time before) the
 267          * next scheduled tick.
 268          */
 269         BUG_ON((ia64_get_itv() & (1 << 16)) == 0);
 270
 271         go[MASTER] = 1;
 272
 273         if (smp_call_function_single(master, sync_master, NULL, 1, 0) < 0) {
 274                 printk(KERN_ERR "sync_itc: failed to get attention of CPU %u!\n", master);
 275                 return;
 276         }
 277
 278         while (go[MASTER])
 279                 cpu_relax();    /* wait for master to be ready */
 280
 281         spin_lock_irqsave(&itc_sync_lock, flags);
 282         {
 283                 for (i = 0; i < NUM_ROUNDS; ++i) {
 284                         delta = get_delta(&rt, &master_time_stamp);
 285                         if (delta == 0) {
 286                                 done = 1;       /* let's lock on to this... */
 287                                 bound = rt;
 288                         }
 289
 290                         if (!done) {
 291                                 if (i > 0) {
 292                                         adjust_latency += -delta;
 293                                         adj = -delta + adjust_latency/4;
 294                                 } else
 295                                         adj = -delta;
 296
 297                                 ia64_set_itc(ia64_get_itc() + adj);
 298                         }
 299 #if DEBUG_ITC_SYNC
 300                         t[i].rt = rt;
 301                         t[i].master = master_time_stamp;
 302                         t[i].diff = delta;
 303                         t[i].lat = adjust_latency/4;
 304 #endif
 305                 }
 306         }
 307         spin_unlock_irqrestore(&itc_sync_lock, flags);
 308
 309 #if DEBUG_ITC_SYNC
 310         for (i = 0; i < NUM_ROUNDS; ++i)
 311                 printk("rt=%5ld master=%5ld diff=%5ld adjlat=%5ld\n",
 312                        t[i].rt, t[i].master, t[i].diff, t[i].lat);
 313 #endif
 314
 315         printk(KERN_INFO "CPU %d: synchronized ITC with CPU %u (last diff %ld cycles, "
 316                "maxerr %lu cycles)\n", smp_processor_id(), master, delta, rt);
 317 }
 318
 319 /*
 320  * Ideally sets up per-cpu profiling hooks.  Doesn't do much now...
 321  */
 322 static inline void __devinit
 323 smp_setup_percpu_timer (void)
 324 {
 325 }
 326
 327 static void __devinit
 328 smp_callin (void)
 329 {
 330         int cpuid, phys_id;
 331         extern void ia64_init_itm(void);
 332
 333 #ifdef CONFIG_PERFMON
 334         extern void pfm_init_percpu(void);
 335 #endif
 336
 337         cpuid = smp_processor_id();
 338         phys_id = hard_smp_processor_id();
 339
 340         if (cpu_online(cpuid)) {
 341                 printk(KERN_ERR "huh, phys CPU#0x%x, CPU#0x%x already present??\n",
 342                        phys_id, cpuid);
 343                 BUG();
 344         }
 345
 346         lock_ipi_calllock();
 347         cpu_set(cpuid, cpu_online_map);
 348         unlock_ipi_calllock();
 349         per_cpu(cpu_state, cpuid) = CPU_ONLINE;
 350
 351         smp_setup_percpu_timer();
 352
 353         ia64_mca_cmc_vector_setup();    /* Setup vector on AP */
 354
 355 #ifdef CONFIG_PERFMON
 356         pfm_init_percpu();
 357 #endif
 358
 359         local_irq_enable();
 360
 361         if (!(sal_platform_features & IA64_SAL_PLATFORM_FEATURE_ITC_DRIFT)) {
 362                 /*
 363                  * Synchronize the ITC with the BP.  Need to do this after irqs are
 364                  * enabled because ia64_sync_itc() calls smp_call_function_single(), which
 365                  * calls spin_unlock_bh(), which calls spin_unlock_bh(), which calls
 366                  * local_bh_enable(), which bugs out if irqs are not enabled...
 367                  */
 368                 Dprintk("Going to syncup ITC with BP.\n");
 369                 ia64_sync_itc(0);
 370         }
 371
 372         /*
 373          * Get our bogomips.
 374          */
 375         ia64_init_itm();
 376         calibrate_delay();
 377         local_cpu_data->loops_per_jiffy = loops_per_jiffy;
 378
 379 #ifdef CONFIG_IA32_SUPPORT
 380         ia32_gdt_init();
 381 #endif
 382
 383         /*
 384          * Allow the master to continue.
 385          */
 386         cpu_set(cpuid, cpu_callin_map);
 387         Dprintk("Stack on CPU %d at about %p\n",cpuid, &cpuid);
 388 }
 389
 390
 391 /*
 392  * Activate a secondary processor.  head.S calls this.
 393  */
 394 int __devinit
 395 start_secondary (void *unused)
 396 {
 397         /* Early console may use I/O ports */
 398         ia64_set_kr(IA64_KR_IO_BASE, __pa(ia64_iobase));
 399         Dprintk("start_secondary: starting CPU 0x%x\n", hard_smp_processor_id());
 400         efi_map_pal_code();
 401         cpu_init();
 402         preempt_disable();
 403         smp_callin();
 404
 405         cpu_idle();
 406         return 0;
 407 }
 408
 409 struct pt_regs * __devinit idle_regs(struct pt_regs *regs)
 410 {
 411         return NULL;
 412 }
 413
 414 struct create_idle {
 415         struct task_struct *idle;
 416         struct completion done;
 417         int cpu;
 418 };
 419
 420 void
 421 do_fork_idle(void *_c_idle)
 422 {
 423         struct create_idle *c_idle = _c_idle;
 424
 425         c_idle->idle = fork_idle(c_idle->cpu);
 426         complete(&c_idle->done);
 427 }
 428
 429 static int __devinit
 430 do_boot_cpu (int sapicid, int cpu)
 431 {
 432         int timeout;
 433         struct create_idle c_idle = {
 434                 .cpu    = cpu,
 435                 .done   = COMPLETION_INITIALIZER(c_idle.done),
 436         };
 437         DECLARE_WORK(work, do_fork_idle, &c_idle);
 438
 439         c_idle.idle = get_idle_for_cpu(cpu);
 440         if (c_idle.idle) {
 441                 init_idle(c_idle.idle, cpu);
 442                 goto do_rest;
 443         }
 444
 445         /*
 446          * We can't use kernel_thread since we must avoid to reschedule the child.
 447          */
 448         if (!keventd_up() || current_is_keventd())
 449                 work.func(work.data);
 450         else {
 451                 schedule_work(&work);
 452                 wait_for_completion(&c_idle.done);
 453         }
 454
 455         if (IS_ERR(c_idle.idle))
 456                 panic("failed fork for CPU %d", cpu);
 457
 458         set_idle_for_cpu(cpu, c_idle.idle);
 459
 460 do_rest:
 461         task_for_booting_cpu = c_idle.idle;
 462
 463         Dprintk("Sending wakeup vector %lu to AP 0x%x/0x%x.\n", ap_wakeup_vector, cpu, sapicid);
 464
 465         set_brendez_area(cpu);
 466         platform_send_ipi(cpu, ap_wakeup_vector, IA64_IPI_DM_INT, 0);
 467
 468         /*
 469          * Wait 10s total for the AP to start
 470          */
 471         Dprintk("Waiting on callin_map ...");
 472         for (timeout = 0; timeout < 100000; timeout++) {
 473                 if (cpu_isset(cpu, cpu_callin_map))
 474                         break;  /* It has booted */
 475                 udelay(100);
 476         }
 477         Dprintk("\n");
 478
 479         if (!cpu_isset(cpu, cpu_callin_map)) {
 480                 printk(KERN_ERR "Processor 0x%x/0x%x is stuck.\n", cpu, sapicid);
 481                 ia64_cpu_to_sapicid[cpu] = -1;
 482                 cpu_clear(cpu, cpu_online_map);  /* was set in smp_callin() */
 483                 return -EINVAL;
 484         }
 485         return 0;
 486 }
 487
 488 static int __init
 489 decay (char *str)
 490 {
 491         int ticks;
 492         get_option (&str, &ticks);
 493         return 1;
 494 }
 495
 496 __setup("decay=", decay);
 497
 498 /*
 499  * Initialize the logical CPU number to SAPICID mapping
 500  */
 501 void __init
 502 smp_build_cpu_map (void)
 503 {
 504         int sapicid, cpu, i;
 505         int boot_cpu_id = hard_smp_processor_id();
 506
 507         for (cpu = 0; cpu < NR_CPUS; cpu++) {
 508                 ia64_cpu_to_sapicid[cpu] = -1;
 509 #ifdef CONFIG_HOTPLUG_CPU
 510                 cpu_set(cpu, cpu_possible_map);
 511 #endif
 512         }
 513
 514         ia64_cpu_to_sapicid[0] = boot_cpu_id;
 515         cpus_clear(cpu_present_map);
 516         cpu_set(0, cpu_present_map);
 517         cpu_set(0, cpu_possible_map);
 518         for (cpu = 1, i = 0; i < smp_boot_data.cpu_count; i++) {
 519                 sapicid = smp_boot_data.cpu_phys_id[i];
 520                 if (sapicid == boot_cpu_id)
 521                         continue;
 522                 cpu_set(cpu, cpu_present_map);
 523                 cpu_set(cpu, cpu_possible_map);
 524                 ia64_cpu_to_sapicid[cpu] = sapicid;
 525                 cpu++;
 526         }
 527 }
 528
 529 /*
 530  * Cycle through the APs sending Wakeup IPIs to boot each.
 531  */
 532 void __init
 533 smp_prepare_cpus (unsigned int max_cpus)
 534 {
 535         int boot_cpu_id = hard_smp_processor_id();
 536
 537         /*
 538          * Initialize the per-CPU profiling counter/multiplier
 539          */
 540
 541         smp_setup_percpu_timer();
 542
 543         /*
 544          * We have the boot CPU online for sure.
 545          */
 546         cpu_set(0, cpu_online_map);
 547         cpu_set(0, cpu_callin_map);
 548
 549         local_cpu_data->loops_per_jiffy = loops_per_jiffy;
 550         ia64_cpu_to_sapicid[0] = boot_cpu_id;
 551
 552         printk(KERN_INFO "Boot processor id 0x%x/0x%x\n", 0, boot_cpu_id);
 553
 554         current_thread_info()->cpu = 0;
 555
 556         /*
 557          * If SMP should be disabled, then really disable it!
 558          */
 559         if (!max_cpus) {
 560                 printk(KERN_INFO "SMP mode deactivated.\n");
 561                 cpus_clear(cpu_online_map);
 562                 cpus_clear(cpu_present_map);
 563                 cpus_clear(cpu_possible_map);
 564                 cpu_set(0, cpu_online_map);
 565                 cpu_set(0, cpu_present_map);
 566                 cpu_set(0, cpu_possible_map);
 567                 return;
 568         }
 569 }
 570
 571 void __devinit smp_prepare_boot_cpu(void)
 572 {
 573         cpu_set(smp_processor_id(), cpu_online_map);
 574         cpu_set(smp_processor_id(), cpu_callin_map);
 575         per_cpu(cpu_state, smp_processor_id()) = CPU_ONLINE;
 576 }
 577
 578 /*
 579  * mt_info[] is a temporary store for all info returned by
 580  * PAL_LOGICAL_TO_PHYSICAL, to be copied into cpuinfo_ia64 when the
 581  * specific cpu comes.
 582  */
 583 static struct {
 584         __u32   socket_id;
 585         __u16   core_id;
 586         __u16   thread_id;
 587         __u16   proc_fixed_addr;
 588         __u8    valid;
 589 } mt_info[NR_CPUS] __devinitdata;
 590
 591 #ifdef CONFIG_HOTPLUG_CPU
 592 static inline void
 593 remove_from_mtinfo(int cpu)
 594 {
 595         int i;
 596
 597         for_each_cpu(i)
 598                 if (mt_info[i].valid &&  mt_info[i].socket_id ==
 599                                                 cpu_data(cpu)->socket_id)
 600                         mt_info[i].valid = 0;
 601 }
 602
 603 static inline void
 604 clear_cpu_sibling_map(int cpu)
 605 {
 606         int i;
 607
 608         for_each_cpu_mask(i, cpu_sibling_map[cpu])
 609                 cpu_clear(cpu, cpu_sibling_map[i]);
 610         for_each_cpu_mask(i, cpu_core_map[cpu])
 611                 cpu_clear(cpu, cpu_core_map[i]);
 612
 613         cpu_sibling_map[cpu] = cpu_core_map[cpu] = CPU_MASK_NONE;
 614 }
 615
 616 static void
 617 remove_siblinginfo(int cpu)
 618 {
 619         int last = 0;
 620
 621         if (cpu_data(cpu)->threads_per_core == 1 &&
 622             cpu_data(cpu)->cores_per_socket == 1) {
 623                 cpu_clear(cpu, cpu_core_map[cpu]);
 624                 cpu_clear(cpu, cpu_sibling_map[cpu]);
 625                 return;
 626         }
 627
 628         last = (cpus_weight(cpu_core_map[cpu]) == 1 ? 1 : 0);
 629
 630         /* remove it from all sibling map's */
 631         clear_cpu_sibling_map(cpu);
 632
 633         /* if this cpu is the last in the core group, remove all its info
 634          * from mt_info structure
 635          */
 636         if (last)
 637                 remove_from_mtinfo(cpu);
 638 }
 639
 640 extern void fixup_irqs(void);
 641 /* must be called with cpucontrol mutex held */
 642 int __cpu_disable(void)
 643 {
 644         int cpu = smp_processor_id();
 645
 646         /*
 647          * dont permit boot processor for now
 648          */
 649         if (cpu == 0)
 650                 return -EBUSY;
 651
 652         remove_siblinginfo(cpu);
 653         cpu_clear(cpu, cpu_online_map);
 654         fixup_irqs();
 655         local_flush_tlb_all();
 656         cpu_clear(cpu, cpu_callin_map);
 657         return 0;
 658 }
 659
 660 void __cpu_die(unsigned int cpu)
 661 {
 662         unsigned int i;
 663
 664         for (i = 0; i < 100; i++) {
 665                 /* They ack this in play_dead by setting CPU_DEAD */
 666                 if (per_cpu(cpu_state, cpu) == CPU_DEAD)
 667                 {
 668                         printk ("CPU %d is now offline\n", cpu);
 669                         return;
 670                 }
 671                 msleep(100);
 672         }
 673         printk(KERN_ERR "CPU %u didn't die...\n", cpu);
 674 }
 675 #else /* !CONFIG_HOTPLUG_CPU */
 676 int __cpu_disable(void)
 677 {
 678         return -ENOSYS;
 679 }
 680
 681 void __cpu_die(unsigned int cpu)
 682 {
 683         /* We said "no" in __cpu_disable */
 684         BUG();
 685 }
 686 #endif /* CONFIG_HOTPLUG_CPU */
 687
 688 void
 689 smp_cpus_done (unsigned int dummy)
 690 {
 691         int cpu;
 692         unsigned long bogosum = 0;
 693
 694         /*
 695          * Allow the user to impress friends.
 696          */
 697
 698         for_each_online_cpu(cpu) {
 699                 bogosum += cpu_data(cpu)->loops_per_jiffy;
 700         }
 701
 702         printk(KERN_INFO "Total of %d processors activated (%lu.%02lu BogoMIPS).\n",
 703                (int)num_online_cpus(), bogosum/(500000/HZ), (bogosum/(5000/HZ))%100);
 704 }
 705
 706 static inline void __devinit
 707 set_cpu_sibling_map(int cpu)
 708 {
 709         int i;
 710
 711         for_each_online_cpu(i) {
 712                 if ((cpu_data(cpu)->socket_id == cpu_data(i)->socket_id)) {
 713                         cpu_set(i, cpu_core_map[cpu]);
 714                         cpu_set(cpu, cpu_core_map[i]);
 715                         if (cpu_data(cpu)->core_id == cpu_data(i)->core_id) {
 716                                 cpu_set(i, cpu_sibling_map[cpu]);
 717                                 cpu_set(cpu, cpu_sibling_map[i]);
 718                         }
 719                 }
 720         }
 721 }
 722
 723 int __devinit
 724 __cpu_up (unsigned int cpu)
 725 {
 726         int ret;
 727         int sapicid;
 728
 729         sapicid = ia64_cpu_to_sapicid[cpu];
 730         if (sapicid == -1)
 731                 return -EINVAL;
 732
 733         /*
 734          * Already booted cpu? not valid anymore since we dont
 735          * do idle loop tightspin anymore.
 736          */
 737         if (cpu_isset(cpu, cpu_callin_map))
 738                 return -EINVAL;
 739
 740         per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
 741         /* Processor goes to start_secondary(), sets online flag */
 742         ret = do_boot_cpu(sapicid, cpu);
 743         if (ret < 0)
 744                 return ret;
 745
 746         if (cpu_data(cpu)->threads_per_core == 1 &&
 747             cpu_data(cpu)->cores_per_socket == 1) {
 748                 cpu_set(cpu, cpu_sibling_map[cpu]);
 749                 cpu_set(cpu, cpu_core_map[cpu]);
 750                 return 0;
 751         }
 752
 753         set_cpu_sibling_map(cpu);
 754
 755         return 0;
 756 }
 757
 758 /*
 759  * Assume that CPU's have been discovered by some platform-dependent interface.  For
 760  * SoftSDV/Lion, that would be ACPI.
 761  *
 762  * Setup of the IPI irq handler is done in irq.c:init_IRQ_SMP().
 763  */
 764 void __init
 765 init_smp_config(void)
 766 {
 767         struct fptr {
 768                 unsigned long fp;
 769                 unsigned long gp;
 770         } *ap_startup;
 771         long sal_ret;
 772
 773         /* Tell SAL where to drop the AP's.  */
 774         ap_startup = (struct fptr *) start_ap;
 775         sal_ret = ia64_sal_set_vectors(SAL_VECTOR_OS_BOOT_RENDEZ,
 776                                        ia64_tpa(ap_startup->fp), ia64_tpa(ap_startup->gp), 0, 0, 0, 0);
 777         if (sal_ret < 0)
 778                 printk(KERN_ERR "SMP: Can't set SAL AP Boot Rendezvous: %s\n",
 779                        ia64_sal_strerror(sal_ret));
 780 }
 781
 782 static inline int __devinit
 783 check_for_mtinfo_index(void)
 784 {
 785         int i;
 786
 787         for_each_cpu(i)
 788                 if (!mt_info[i].valid)
 789                         return i;
 790
 791         return -1;
 792 }
 793
 794 /*
 795  * Search the mt_info to find out if this socket's cid/tid information is
 796  * cached or not. If the socket exists, fill in the core_id and thread_id
 797  * in cpuinfo
 798  */
 799 static int __devinit
 800 check_for_new_socket(__u16 logical_address, struct cpuinfo_ia64 *c)
 801 {
 802         int i;
 803         __u32 sid = c->socket_id;
 804
 805         for_each_cpu(i) {
 806                 if (mt_info[i].valid && mt_info[i].proc_fixed_addr == logical_address
 807                     && mt_info[i].socket_id == sid) {
 808                         c->core_id = mt_info[i].core_id;
 809                         c->thread_id = mt_info[i].thread_id;
 810                         return 1; /* not a new socket */
 811                 }
 812         }
 813         return 0;
 814 }
 815
 816 /*
 817  * identify_siblings(cpu) gets called from identify_cpu. This populates the
 818  * information related to logical execution units in per_cpu_data structure.
 819  */
 820 void __devinit
 821 identify_siblings(struct cpuinfo_ia64 *c)
 822 {
 823         s64 status;
 824         u16 pltid;
 825         u64 proc_fixed_addr;
 826         int count, i;
 827         pal_logical_to_physical_t info;
 828
 829         if (smp_num_cpucores == 1 && smp_num_siblings == 1)
 830                 return;
 831
 832         if ((status = ia64_pal_logical_to_phys(0, &info)) != PAL_STATUS_SUCCESS) {
 833                 printk(KERN_ERR "ia64_pal_logical_to_phys failed with %ld\n",
 834                        status);
 835                 return;
 836         }
 837         if ((status = ia64_sal_physical_id_info(&pltid)) != PAL_STATUS_SUCCESS) {
 838                 printk(KERN_ERR "ia64_sal_pltid failed with %ld\n", status);
 839                 return;
 840         }
 841         if ((status = ia64_pal_fixed_addr(&proc_fixed_addr)) != PAL_STATUS_SUCCESS) {
 842                 printk(KERN_ERR "ia64_pal_fixed_addr failed with %ld\n", status);
 843                 return;
 844         }
 845
 846         c->socket_id =  (pltid << 8) | info.overview_ppid;
 847         c->cores_per_socket = info.overview_cpp;
 848         c->threads_per_core = info.overview_tpc;
 849         count = c->num_log = info.overview_num_log;
 850
 851         /* If the thread and core id information is already cached, then
 852          * we will simply update cpu_info and return. Otherwise, we will
 853          * do the PAL calls and cache core and thread id's of all the siblings.
 854          */
 855         if (check_for_new_socket(proc_fixed_addr, c))
 856                 return;
 857
 858         for (i = 0; i < count; i++) {
 859                 int index;
 860
 861                 if (i && (status = ia64_pal_logical_to_phys(i, &info))
 862                           != PAL_STATUS_SUCCESS) {
 863                         printk(KERN_ERR "ia64_pal_logical_to_phys failed"
 864                                         " with %ld\n", status);
 865                         return;
 866                 }
 867                 if (info.log2_la == proc_fixed_addr) {
 868                         c->core_id = info.log1_cid;
 869                         c->thread_id = info.log1_tid;
 870                 }
 871
 872                 index = check_for_mtinfo_index();
 873                 /* We will not do the mt_info caching optimization in this case.
 874                  */
 875                 if (index < 0)
 876                         continue;
 877
 878                 mt_info[index].valid = 1;
 879                 mt_info[index].socket_id = c->socket_id;
 880                 mt_info[index].core_id = info.log1_cid;
 881                 mt_info[index].thread_id = info.log1_tid;
 882                 mt_info[index].proc_fixed_addr = info.log2_la;
 883         }
 884 }