arch/parisc/kernel/smp.c

   1 /*
   2 ** SMP Support
   3 **
   4 ** Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
   5 ** Copyright (C) 1999 David Mosberger-Tang <davidm@hpl.hp.com>
   6 ** Copyright (C) 2001 Grant Grundler <grundler@parisc-linux.org>
   7 **
   8 ** Lots of stuff stolen from arch/alpha/kernel/smp.c
   9 ** ...and then parisc stole from arch/ia64/kernel/smp.c. Thanks David! :^)
  10 **
  11 ** Thanks to John Curry and Ullas Ponnadi. I learned alot from their work.
  12 ** -grant (1/12/2001)
  13 **
  14 **      This program is free software; you can redistribute it and/or modify
  15 **      it under the terms of the GNU General Public License as published by
  16 **      the Free Software Foundation; either version 2 of the License, or
  17 **      (at your option) any later version.
  18 */
  19 #undef ENTRY_SYS_CPUS   /* syscall support for iCOD-like functionality */
  20
  21 #include <linux/autoconf.h>
  22
  23 #include <linux/types.h>
  24 #include <linux/spinlock.h>
  25 #include <linux/slab.h>
  26
  27 #include <linux/kernel.h>
  28 #include <linux/module.h>
  29 #include <linux/sched.h>
  30 #include <linux/init.h>
  31 #include <linux/interrupt.h>
  32 #include <linux/smp.h>
  33 #include <linux/kernel_stat.h>
  34 #include <linux/mm.h>
  35 #include <linux/delay.h>
  36
  37 #include <asm/system.h>
  38 #include <asm/atomic.h>
  39 #include <asm/bitops.h>
  40 #include <asm/current.h>
  41 #include <asm/delay.h>
  42 #include <asm/pgalloc.h>        /* for flush_tlb_all() proto/macro */
  43
  44 #include <asm/io.h>
  45 #include <asm/irq.h>            /* for CPU_IRQ_REGION and friends */
  46 #include <asm/mmu_context.h>
  47 #include <asm/page.h>
  48 #include <asm/pgtable.h>
  49 #include <asm/pgalloc.h>
  50 #include <asm/processor.h>
  51 #include <asm/ptrace.h>
  52 #include <asm/unistd.h>
  53 #include <asm/cacheflush.h>
  54
  55 #define kDEBUG 0
  56
  57 spinlock_t pa_dbit_lock = SPIN_LOCK_UNLOCKED;
  58
  59 spinlock_t smp_lock = SPIN_LOCK_UNLOCKED;
  60
  61 volatile struct task_struct *smp_init_current_idle_task;
  62
  63 static volatile int smp_commenced = 0;   /* Set when the idlers are all forked */
  64 static volatile int cpu_now_booting = 0;      /* track which CPU is booting */
  65 cpumask_t cpu_online_map = CPU_MASK_NONE;   /* Bitmap of online CPUs */
  66 #define IS_LOGGED_IN(cpunum) (cpu_isset(cpunum, cpu_online_map))
  67
  68 EXPORT_SYMBOL(cpu_online_map);
  69
  70 int smp_num_cpus = 1;
  71 int smp_threads_ready = 0;
  72 unsigned long cache_decay_ticks;
  73 static int max_cpus = -1;                            /* Command line */
  74 cpumask_t cpu_present_mask;
  75
  76 EXPORT_SYMBOL(cpu_present_mask);
  77
  78 struct smp_call_struct {
  79         void (*func) (void *info);
  80         void *info;
  81         long wait;
  82         atomic_t unstarted_count;
  83         atomic_t unfinished_count;
  84 };
  85 static volatile struct smp_call_struct *smp_call_function_data;
  86
  87 enum ipi_message_type {
  88         IPI_NOP=0,
  89         IPI_RESCHEDULE=1,
  90         IPI_CALL_FUNC,
  91         IPI_CPU_START,
  92         IPI_CPU_STOP,
  93         IPI_CPU_TEST
  94 };
  95
  96
  97 /********** SMP inter processor interrupt and communication routines */
  98
  99 #undef PER_CPU_IRQ_REGION
 100 #ifdef PER_CPU_IRQ_REGION
 101 /* XXX REVISIT Ignore for now.
 102 **    *May* need this "hook" to register IPI handler
 103 **    once we have perCPU ExtIntr switch tables.
 104 */
 105 static void
 106 ipi_init(int cpuid)
 107 {
 108
 109         /* If CPU is present ... */
 110 #ifdef ENTRY_SYS_CPUS
 111         /* *and* running (not stopped) ... */
 112 #error iCOD support wants state checked here.
 113 #endif
 114
 115 #error verify IRQ_OFFSET(IPI_IRQ) is ipi_interrupt() in new IRQ region
 116
 117         if(IS_LOGGED_IN(cpuid) )
 118         {
 119                 switch_to_idle_task(current);
 120         }
 121
 122         return;
 123 }
 124 #endif
 125
 126
 127 /*
 128 ** Yoink this CPU from the runnable list...
 129 **
 130 */
 131 static void
 132 halt_processor(void)
 133 {
 134 #ifdef ENTRY_SYS_CPUS
 135 #error halt_processor() needs rework
 136 /*
 137 ** o migrate I/O interrupts off this CPU.
 138 ** o leave IPI enabled - __cli() will disable IPI.
 139 ** o leave CPU in online map - just change the state
 140 */
 141         cpu_data[this_cpu].state = STATE_STOPPED;
 142         mark_bh(IPI_BH);
 143 #else
 144         /* REVISIT : redirect I/O Interrupts to another CPU? */
 145         /* REVISIT : does PM *know* this CPU isn't available? */
 146         cpu_clear(smp_processor_id(), cpu_online_map);
 147         local_irq_disable();
 148         for (;;)
 149                 ;
 150 #endif
 151 }
 152
 153
 154 irqreturn_t
 155 ipi_interrupt(int irq, void *dev_id, struct pt_regs *regs)
 156 {
 157         int this_cpu = smp_processor_id();
 158         struct cpuinfo_parisc *p = &cpu_data[this_cpu];
 159         unsigned long ops;
 160         unsigned long flags;
 161
 162         /* Count this now; we may make a call that never returns. */
 163         p->ipi_count++;
 164
 165         mb();   /* Order interrupt and bit testing. */
 166
 167         for (;;) {
 168                 spin_lock_irqsave(&(p->lock),flags);
 169                 ops = p->pending_ipi;
 170                 p->pending_ipi = 0;
 171                 spin_unlock_irqrestore(&(p->lock),flags);
 172
 173                 mb(); /* Order bit clearing and data access. */
 174
 175                 if (!ops)
 176                     break;
 177
 178                 while (ops) {
 179                         unsigned long which = ffz(~ops);
 180
 181                         switch (which) {
 182                         case IPI_RESCHEDULE:
 183 #if (kDEBUG>=100)
 184                                 printk(KERN_DEBUG "CPU%d IPI_RESCHEDULE\n",this_cpu);
 185 #endif /* kDEBUG */
 186                                 ops &= ~(1 << IPI_RESCHEDULE);
 187                                 /*
 188                                  * Reschedule callback.  Everything to be
 189                                  * done is done by the interrupt return path.
 190                                  */
 191                                 break;
 192
 193                         case IPI_CALL_FUNC:
 194 #if (kDEBUG>=100)
 195                                 printk(KERN_DEBUG "CPU%d IPI_CALL_FUNC\n",this_cpu);
 196 #endif /* kDEBUG */
 197                                 ops &= ~(1 << IPI_CALL_FUNC);
 198                                 {
 199                                         volatile struct smp_call_struct *data;
 200                                         void (*func)(void *info);
 201                                         void *info;
 202                                         int wait;
 203
 204                                         data = smp_call_function_data;
 205                                         func = data->func;
 206                                         info = data->info;
 207                                         wait = data->wait;
 208
 209                                         mb();
 210                                         atomic_dec ((atomic_t *)&data->unstarted_count);
 211
 212                                         /* At this point, *data can't
 213                                          * be relied upon.
 214                                          */
 215
 216                                         (*func)(info);
 217
 218                                         /* Notify the sending CPU that the
 219                                          * task is done.
 220                                          */
 221                                         mb();
 222                                         if (wait)
 223                                                 atomic_dec ((atomic_t *)&data->unfinished_count);
 224                                 }
 225                                 break;
 226
 227                         case IPI_CPU_START:
 228 #if (kDEBUG>=100)
 229                                 printk(KERN_DEBUG "CPU%d IPI_CPU_START\n",this_cpu);
 230 #endif /* kDEBUG */
 231                                 ops &= ~(1 << IPI_CPU_START);
 232 #ifdef ENTRY_SYS_CPUS
 233                                 p->state = STATE_RUNNING;
 234 #endif
 235                                 break;
 236
 237                         case IPI_CPU_STOP:
 238 #if (kDEBUG>=100)
 239                                 printk(KERN_DEBUG "CPU%d IPI_CPU_STOP\n",this_cpu);
 240 #endif /* kDEBUG */
 241                                 ops &= ~(1 << IPI_CPU_STOP);
 242 #ifdef ENTRY_SYS_CPUS
 243 #else
 244                                 halt_processor();
 245 #endif
 246                                 break;
 247
 248                         case IPI_CPU_TEST:
 249 #if (kDEBUG>=100)
 250                                 printk(KERN_DEBUG "CPU%d is alive!\n",this_cpu);
 251 #endif /* kDEBUG */
 252                                 ops &= ~(1 << IPI_CPU_TEST);
 253                                 break;
 254
 255                         default:
 256                                 printk(KERN_CRIT "Unknown IPI num on CPU%d: %lu\n",
 257                                         this_cpu, which);
 258                                 ops &= ~(1 << which);
 259                                 return IRQ_NONE;
 260                         } /* Switch */
 261                 } /* while (ops) */
 262         }
 263         return IRQ_HANDLED;
 264 }
 265
 266
 267 static inline void
 268 ipi_send(int cpu, enum ipi_message_type op)
 269 {
 270         struct cpuinfo_parisc *p = &cpu_data[cpu];
 271         unsigned long flags;
 272
 273         spin_lock_irqsave(&(p->lock),flags);
 274         p->pending_ipi |= 1 << op;
 275         __raw_writel(IRQ_OFFSET(IPI_IRQ), cpu_data[cpu].hpa);
 276         spin_unlock_irqrestore(&(p->lock),flags);
 277 }
 278
 279
 280 static inline void
 281 send_IPI_single(int dest_cpu, enum ipi_message_type op)
 282 {
 283         if (dest_cpu == NO_PROC_ID) {
 284                 BUG();
 285                 return;
 286         }
 287
 288         ipi_send(dest_cpu, op);
 289 }
 290
 291 static inline void
 292 send_IPI_allbutself(enum ipi_message_type op)
 293 {
 294         int i;
 295
 296         for (i = 0; i < smp_num_cpus; i++) {
 297                 if (i != smp_processor_id())
 298                         send_IPI_single(i, op);
 299         }
 300 }
 301
 302 inline void
 303 smp_send_stop(void)     { send_IPI_allbutself(IPI_CPU_STOP); }
 304
 305 static inline void
 306 smp_send_start(void)    { send_IPI_allbutself(IPI_CPU_START); }
 307
 308 void
 309 smp_send_reschedule(int cpu) { send_IPI_single(cpu, IPI_RESCHEDULE); }
 310
 311
 312 /**
 313  * Run a function on all other CPUs.
 314  *  <func>      The function to run. This must be fast and non-blocking.
 315  *  <info>      An arbitrary pointer to pass to the function.
 316  *  <retry>     If true, keep retrying until ready.
 317  *  <wait>      If true, wait until function has completed on other CPUs.
 318  *  [RETURNS]   0 on success, else a negative status code.
 319  *
 320  * Does not return until remote CPUs are nearly ready to execute <func>
 321  * or have executed.
 322  */
 323
 324 int
 325 smp_call_function (void (*func) (void *info), void *info, int retry, int wait)
 326 {
 327         struct smp_call_struct data;
 328         unsigned long timeout;
 329         static spinlock_t lock = SPIN_LOCK_UNLOCKED;
 330
 331         data.func = func;
 332         data.info = info;
 333         data.wait = wait;
 334         atomic_set(&data.unstarted_count, smp_num_cpus - 1);
 335         atomic_set(&data.unfinished_count, smp_num_cpus - 1);
 336
 337         if (retry) {
 338                 spin_lock (&lock);
 339                 while (smp_call_function_data != 0)
 340                         barrier();
 341         }
 342         else {
 343                 spin_lock (&lock);
 344                 if (smp_call_function_data) {
 345                         spin_unlock (&lock);
 346                         return -EBUSY;
 347                 }
 348         }
 349
 350         smp_call_function_data = &data;
 351         spin_unlock (&lock);
 352
 353         /*  Send a message to all other CPUs and wait for them to respond  */
 354         send_IPI_allbutself(IPI_CALL_FUNC);
 355
 356         /*  Wait for response  */
 357         timeout = jiffies + HZ;
 358         while ( (atomic_read (&data.unstarted_count) > 0) &&
 359                 time_before (jiffies, timeout) )
 360                 barrier ();
 361
 362         /* We either got one or timed out. Release the lock */
 363
 364         mb();
 365         smp_call_function_data = NULL;
 366         if (atomic_read (&data.unstarted_count) > 0) {
 367                 printk(KERN_CRIT "SMP CALL FUNCTION TIMED OUT! (cpu=%d)\n",
 368                       smp_processor_id());
 369                 return -ETIMEDOUT;
 370         }
 371
 372         while (wait && atomic_read (&data.unfinished_count) > 0)
 373                         barrier ();
 374
 375         return 0;
 376 }
 377
 378 EXPORT_SYMBOL(smp_call_function);
 379
 380
 381
 382 /*
 383  *      Setup routine for controlling SMP activation
 384  *
 385  *      Command-line option of "nosmp" or "maxcpus=0" will disable SMP
 386  *      activation entirely (the MPS table probe still happens, though).
 387  *
 388  *      Command-line option of "maxcpus=<NUM>", where <NUM> is an integer
 389  *      greater than 0, limits the maximum number of CPUs activated in
 390  *      SMP mode to <NUM>.
 391  */
 392
 393 static int __init nosmp(char *str)
 394 {
 395         max_cpus = 0;
 396         return 1;
 397 }
 398
 399 __setup("nosmp", nosmp);
 400
 401 static int __init maxcpus(char *str)
 402 {
 403         get_option(&str, &max_cpus);
 404         return 1;
 405 }
 406
 407 __setup("maxcpus=", maxcpus);
 408
 409 /*
 410  * Flush all other CPU's tlb and then mine.  Do this with on_each_cpu()
 411  * as we want to ensure all TLB's flushed before proceeding.
 412  */
 413
 414 extern void flush_tlb_all_local(void);
 415
 416 void
 417 smp_flush_tlb_all(void)
 418 {
 419         on_each_cpu((void (*)(void *))flush_tlb_all_local, NULL, 1, 1);
 420 }
 421
 422
 423 void
 424 smp_do_timer(struct pt_regs *regs)
 425 {
 426         int cpu = smp_processor_id();
 427         struct cpuinfo_parisc *data = &cpu_data[cpu];
 428
 429         if (!--data->prof_counter) {
 430                 data->prof_counter = data->prof_multiplier;
 431                 update_process_times(user_mode(regs));
 432         }
 433 }
 434
 435 /*
 436  * Called by secondaries to update state and initialize CPU registers.
 437  */
 438 static void __init
 439 smp_cpu_init(int cpunum)
 440 {
 441         extern int init_per_cpu(int);  /* arch/parisc/kernel/setup.c */
 442         extern void init_IRQ(void);    /* arch/parisc/kernel/irq.c */
 443
 444         /* Set modes and Enable floating point coprocessor */
 445         (void) init_per_cpu(cpunum);
 446
 447         disable_sr_hashing();
 448
 449         mb();
 450
 451         /* Well, support 2.4 linux scheme as well. */
 452         if (cpu_test_and_set(cpunum, cpu_online_map))
 453         {
 454                 extern void machine_halt(void); /* arch/parisc.../process.c */
 455
 456                 printk(KERN_CRIT "CPU#%d already initialized!\n", cpunum);
 457                 machine_halt();
 458         }
 459
 460         /* Initialise the idle task for this CPU */
 461         atomic_inc(&init_mm.mm_count);
 462         current->active_mm = &init_mm;
 463         if(current->mm)
 464                 BUG();
 465         enter_lazy_tlb(&init_mm, current);
 466
 467         init_IRQ();   /* make sure no IRQ's are enabled or pending */
 468 }
 469
 470
 471 /*
 472  * Slaves start using C here. Indirectly called from smp_slave_stext.
 473  * Do what start_kernel() and main() do for boot strap processor (aka monarch)
 474  */
 475 void __init smp_callin(void)
 476 {
 477         extern void cpu_idle(void);     /* arch/parisc/kernel/process.c */
 478         int slave_id = cpu_now_booting;
 479 #if 0
 480         void *istack;
 481 #endif
 482
 483         smp_cpu_init(slave_id);
 484
 485 #if 0   /* NOT WORKING YET - see entry.S */
 486         istack = (void *)__get_free_pages(GFP_KERNEL,ISTACK_ORDER);
 487         if (istack == NULL) {
 488             printk(KERN_CRIT "Failed to allocate interrupt stack for cpu %d\n",slave_id);
 489             BUG();
 490         }
 491         mtctl(istack,31);
 492 #endif
 493
 494         flush_cache_all_local(); /* start with known state */
 495         flush_tlb_all_local();
 496
 497         local_irq_enable();  /* Interrupts have been off until now */
 498
 499         /* Slaves wait here until Big Poppa daddy say "jump" */
 500         mb();   /* PARANOID */
 501         while (!smp_commenced) ;
 502         mb();   /* PARANOID */
 503
 504         cpu_idle();      /* Wait for timer to schedule some work */
 505
 506         /* NOTREACHED */
 507         panic("smp_callin() AAAAaaaaahhhh....\n");
 508 }
 509
 510 /*
 511  * Create the idle task for a new Slave CPU.  DO NOT use kernel_thread()
 512  * because that could end up calling schedule(). If it did, the new idle
 513  * task could get scheduled before we had a chance to remove it from the
 514  * run-queue...
 515  */
 516 static struct task_struct *fork_by_hand(void)
 517 {
 518         struct pt_regs regs;
 519
 520         /*
 521          * don't care about the regs settings since
 522          * we'll never reschedule the forked task.
 523          */
 524         return copy_process(CLONE_VM|CLONE_IDLETASK, 0, &regs, 0, NULL, NULL);
 525 }
 526
 527
 528 /*
 529  * Bring one cpu online.
 530  */
 531 static int __init smp_boot_one_cpu(int cpuid, int cpunum)
 532 {
 533         struct task_struct *idle;
 534         long timeout;
 535
 536         /*
 537          * Create an idle task for this CPU.  Note the address wed* give
 538          * to kernel_thread is irrelevant -- it's going to start
 539          * where OS_BOOT_RENDEVZ vector in SAL says to start.  But
 540          * this gets all the other task-y sort of data structures set
 541          * up like we wish.   We need to pull the just created idle task
 542          * off the run queue and stuff it into the init_tasks[] array.
 543          * Sheesh . . .
 544          */
 545
 546         idle = fork_by_hand();
 547         if (IS_ERR(idle))
 548                 panic("SMP: fork failed for CPU:%d", cpuid);
 549
 550         wake_up_forked_process(idle);
 551         init_idle(idle, cpunum);
 552         unhash_process(idle);
 553         idle->thread_info->cpu = cpunum;
 554
 555         /* Let _start know what logical CPU we're booting
 556         ** (offset into init_tasks[],cpu_data[])
 557         */
 558         cpu_now_booting = cpunum;
 559
 560         /*
 561         ** boot strap code needs to know the task address since
 562         ** it also contains the process stack.
 563         */
 564         smp_init_current_idle_task = idle ;
 565         mb();
 566
 567         /*
 568         ** This gets PDC to release the CPU from a very tight loop.
 569         ** See MEM_RENDEZ comments in head.S.
 570         */
 571         __raw_writel(IRQ_OFFSET(TIMER_IRQ), cpu_data[cpunum].hpa);
 572         mb();
 573
 574         /*
 575          * OK, wait a bit for that CPU to finish staggering about.
 576          * Slave will set a bit when it reaches smp_cpu_init() and then
 577          * wait for smp_commenced to be 1.
 578          * Once we see the bit change, we can move on.
 579          */
 580         for (timeout = 0; timeout < 10000; timeout++) {
 581                 if(IS_LOGGED_IN(cpunum)) {
 582                         /* Which implies Slave has started up */
 583                         cpu_now_booting = 0;
 584                         smp_init_current_idle_task = NULL;
 585                         goto alive ;
 586                 }
 587                 udelay(100);
 588                 barrier();
 589         }
 590
 591         put_task_struct(idle);
 592         idle = NULL;
 593
 594         printk(KERN_CRIT "SMP: CPU:%d is stuck.\n", cpuid);
 595         return -1;
 596
 597 alive:
 598         /* Remember the Slave data */
 599 #if (kDEBUG>=100)
 600         printk(KERN_DEBUG "SMP: CPU:%d (num %d) came alive after %ld _us\n",
 601                 cpuid,  cpunum, timeout * 100);
 602 #endif /* kDEBUG */
 603 #ifdef ENTRY_SYS_CPUS
 604         cpu_data[cpunum].state = STATE_RUNNING;
 605 #endif
 606         return 0;
 607 }
 608
 609
 610
 611
 612 /*
 613 ** inventory.c:do_inventory() has already 'discovered' the additional CPU's.
 614 ** We are ready to wrest them from PDC's control now.
 615 ** Called by smp_init bring all the secondaries online and hold them.
 616 **
 617 ** o Setup of the IPI irq handler is done in irq.c.
 618 ** o MEM_RENDEZ is initialzed in head.S:stext()
 619 **
 620 */
 621 void __init smp_boot_cpus(void)
 622 {
 623         int i, cpu_count = 1;
 624         unsigned long bogosum = cpu_data[0].loops_per_jiffy; /* Count Monarch */
 625
 626         /* REVISIT - assumes first CPU reported by PAT PDC is BSP */
 627         int bootstrap_processor=cpu_data[0].cpuid;      /* CPU ID of BSP */
 628
 629         /* Setup BSP mappings */
 630         printk(KERN_DEBUG "SMP: bootstrap CPU ID is %d\n",bootstrap_processor);
 631         init_task.thread_info->cpu = bootstrap_processor;
 632         current->thread_info->cpu = bootstrap_processor;
 633         /* Mark Boostrap processor as present */
 634         cpu_online_map = cpumask_of_cpu(bootstrap_processor);
 635         current->active_mm = &init_mm;
 636
 637 #ifdef ENTRY_SYS_CPUS
 638         cpu_data[0].state = STATE_RUNNING;
 639 #endif
 640         cpu_present_mask = cpumask_of_cpu(bootstrap_processor);
 641
 642         /* Nothing to do when told not to.  */
 643         if (max_cpus == 0) {
 644                 printk(KERN_INFO "SMP mode deactivated.\n");
 645                 return;
 646         }
 647
 648         if (max_cpus != -1)
 649                 printk(KERN_INFO "Limiting CPUs to %d\n", max_cpus);
 650
 651         /* We found more than one CPU.... */
 652         if (boot_cpu_data.cpu_count > 1) {
 653
 654                 for (i = 0; i < NR_CPUS; i++) {
 655                         if (cpu_data[i].cpuid == NO_PROC_ID ||
 656                             cpu_data[i].cpuid == bootstrap_processor)
 657                                 continue;
 658
 659                         if (smp_boot_one_cpu(cpu_data[i].cpuid, cpu_count) < 0)
 660                                 continue;
 661
 662                         bogosum += cpu_data[i].loops_per_jiffy;
 663                         cpu_count++; /* Count good CPUs only... */
 664
 665                         cpu_present_mask |= 1UL << i;
 666
 667                         /* Bail when we've started as many CPUS as told to */
 668                         if (cpu_count == max_cpus)
 669                                 break;
 670                 }
 671         }
 672         if (cpu_count == 1) {
 673                 printk(KERN_INFO "SMP: Bootstrap processor only.\n");
 674         }
 675
 676         /*
 677          * FIXME very rough.
 678          */
 679         cache_decay_ticks = HZ/100;
 680
 681         printk(KERN_INFO "SMP: Total %d of %d processors activated "
 682                "(%lu.%02lu BogoMIPS noticed) (Present Mask: %lu).\n",
 683                cpu_count, boot_cpu_data.cpu_count, (bogosum + 25) / 5000,
 684                ((bogosum + 25) / 50) % 100, cpu_present_mask);
 685
 686         smp_num_cpus = cpu_count;
 687 #ifdef PER_CPU_IRQ_REGION
 688         ipi_init();
 689 #endif
 690         return;
 691 }
 692
 693 /*
 694  * Called from main.c by Monarch Processor.
 695  * After this, any CPU can schedule any task.
 696  */
 697 void smp_commence(void)
 698 {
 699         smp_commenced = 1;
 700         mb();
 701         return;
 702 }
 703
 704 /*
 705  * XXX FIXME : do nothing
 706  */
 707 void smp_cpus_done(unsigned int cpu_max)
 708 {
 709         smp_threads_ready = 1;
 710 }
 711
 712 void __init smp_prepare_cpus(unsigned int max_cpus)
 713 {
 714         smp_boot_cpus();
 715 }
 716
 717 void __devinit smp_prepare_boot_cpu(void)
 718 {
 719         cpu_set(smp_processor_id(), cpu_online_map);
 720         cpu_set(smp_processor_id(), cpu_present_mask);
 721 }
 722
 723 int __devinit __cpu_up(unsigned int cpu)
 724 {
 725         return cpu_online(cpu) ? 0 : -ENOSYS;
 726 }
 727
 728
 729
 730 #ifdef ENTRY_SYS_CPUS
 731 /* Code goes along with:
 732 **    entry.s:        ENTRY_NAME(sys_cpus)   / * 215, for cpu stat * /
 733 */
 734 int sys_cpus(int argc, char **argv)
 735 {
 736         int i,j=0;
 737         extern int current_pid(int cpu);
 738
 739         if( argc > 2 ) {
 740                 printk("sys_cpus:Only one argument supported\n");
 741                 return (-1);
 742         }
 743         if ( argc == 1 ){
 744
 745 #ifdef DUMP_MORE_STATE
 746                 for(i=0; i<NR_CPUS; i++) {
 747                         int cpus_per_line = 4;
 748                         if(IS_LOGGED_IN(i)) {
 749                                 if (j++ % cpus_per_line)
 750                                         printk(" %3d",i);
 751                                 else
 752                                         printk("\n %3d",i);
 753                         }
 754                 }
 755                 printk("\n");
 756 #else
 757                 printk("\n 0\n");
 758 #endif
 759         } else if((argc==2) && !(strcmp(argv[1],"-l"))) {
 760                 printk("\nCPUSTATE  TASK CPUNUM CPUID HARDCPU(HPA)\n");
 761 #ifdef DUMP_MORE_STATE
 762                 for(i=0;i<NR_CPUS;i++) {
 763                         if (!IS_LOGGED_IN(i))
 764                                 continue;
 765                         if (cpu_data[i].cpuid != NO_PROC_ID) {
 766                                 switch(cpu_data[i].state) {
 767                                         case STATE_RENDEZVOUS:
 768                                                 printk("RENDEZVS ");
 769                                                 break;
 770                                         case STATE_RUNNING:
 771                                                 printk((current_pid(i)!=0) ? "RUNNING  " : "IDLING   ");
 772                                                 break;
 773                                         case STATE_STOPPED:
 774                                                 printk("STOPPED  ");
 775                                                 break;
 776                                         case STATE_HALTED:
 777                                                 printk("HALTED   ");
 778                                                 break;
 779                                         default:
 780                                                 printk("%08x?", cpu_data[i].state);
 781                                                 break;
 782                                 }
 783                                 if(IS_LOGGED_IN(i)) {
 784                                         printk(" %4d",current_pid(i));
 785                                 }
 786                                 printk(" %6d",cpu_number_map(i));
 787                                 printk(" %5d",i);
 788                                 printk(" 0x%lx\n",cpu_data[i].hpa);
 789                         }
 790                 }
 791 #else
 792                 printk("\n%s  %4d      0     0 --------",
 793                         (current->pid)?"RUNNING ": "IDLING  ",current->pid);
 794 #endif
 795         } else if ((argc==2) && !(strcmp(argv[1],"-s"))) {
 796 #ifdef DUMP_MORE_STATE
 797                 printk("\nCPUSTATE   CPUID\n");
 798                 for (i=0;i<NR_CPUS;i++) {
 799                         if (!IS_LOGGED_IN(i))
 800                                 continue;
 801                         if (cpu_data[i].cpuid != NO_PROC_ID) {
 802                                 switch(cpu_data[i].state) {
 803                                         case STATE_RENDEZVOUS:
 804                                                 printk("RENDEZVS");break;
 805                                         case STATE_RUNNING:
 806                                                 printk((current_pid(i)!=0) ? "RUNNING " : "IDLING");
 807                                                 break;
 808                                         case STATE_STOPPED:
 809                                                 printk("STOPPED ");break;
 810                                         case STATE_HALTED:
 811                                                 printk("HALTED  ");break;
 812                                         default:
 813                                 }
 814                                 printk("  %5d\n",i);
 815                         }
 816                 }
 817 #else
 818                 printk("\n%s    CPU0",(current->pid==0)?"RUNNING ":"IDLING  ");
 819 #endif
 820         } else {
 821                 printk("sys_cpus:Unknown request\n");
 822                 return (-1);
 823         }
 824         return 0;
 825 }
 826 #endif /* ENTRY_SYS_CPUS */
 827
 828 #ifdef CONFIG_PROC_FS
 829 int __init
 830 setup_profiling_timer(unsigned int multiplier)
 831 {
 832         return -EINVAL;
 833 }
 834 #endif