arch/powerpc/kernel/irq.c

   1 /*
   2  *  Derived from arch/i386/kernel/irq.c
   3  *    Copyright (C) 1992 Linus Torvalds
   4  *  Adapted from arch/i386 by Gary Thomas
   5  *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
   6  *  Updated and modified by Cort Dougan <cort@fsmlabs.com>
   7  *    Copyright (C) 1996-2001 Cort Dougan
   8  *  Adapted for Power Macintosh by Paul Mackerras
   9  *    Copyright (C) 1996 Paul Mackerras (paulus@cs.anu.edu.au)
  10  *  Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk).
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version
  15  * 2 of the License, or (at your option) any later version.
  16  *
  17  * This file contains the code used by various IRQ handling routines:
  18  * asking for different IRQ's should be done through these routines
  19  * instead of just grabbing them. Thus setups with different IRQ numbers
  20  * shouldn't result in any weird surprises, and installing new handlers
  21  * should be easier.
  22  *
  23  * The MPC8xx has an interrupt mask in the SIU.  If a bit is set, the
  24  * interrupt is _enabled_.  As expected, IRQ0 is bit 0 in the 32-bit
  25  * mask register (of which only 16 are defined), hence the weird shifting
  26  * and complement of the cached_irq_mask.  I want to be able to stuff
  27  * this right into the SIU SMASK register.
  28  * Many of the prep/chrp functions are conditional compiled on CONFIG_8xx
  29  * to reduce code space and undefined function references.
  30  */
  31
  32 #undef DEBUG
  33
  34 #include <linux/module.h>
  35 #include <linux/threads.h>
  36 #include <linux/kernel_stat.h>
  37 #include <linux/signal.h>
  38 #include <linux/sched.h>
  39 #include <linux/ptrace.h>
  40 #include <linux/ioport.h>
  41 #include <linux/interrupt.h>
  42 #include <linux/timex.h>
  43 #include <linux/init.h>
  44 #include <linux/slab.h>
  45 #include <linux/delay.h>
  46 #include <linux/irq.h>
  47 #include <linux/seq_file.h>
  48 #include <linux/cpumask.h>
  49 #include <linux/profile.h>
  50 #include <linux/bitops.h>
  51 #include <linux/list.h>
  52 #include <linux/radix-tree.h>
  53 #include <linux/mutex.h>
  54 #include <linux/bootmem.h>
  55 #include <linux/pci.h>
  56
  57 #include <asm/uaccess.h>
  58 #include <asm/system.h>
  59 #include <asm/io.h>
  60 #include <asm/pgtable.h>
  61 #include <asm/irq.h>
  62 #include <asm/cache.h>
  63 #include <asm/prom.h>
  64 #include <asm/ptrace.h>
  65 #include <asm/machdep.h>
  66 #include <asm/udbg.h>
  67 #ifdef CONFIG_PPC_ISERIES
  68 #include <asm/paca.h>
  69 #endif
  70
  71 int __irq_offset_value;
  72 static int ppc_spurious_interrupts;
  73
  74 #ifdef CONFIG_PPC32
  75 EXPORT_SYMBOL(__irq_offset_value);
  76 atomic_t ppc_n_lost_interrupts;
  77
  78 #ifndef CONFIG_PPC_MERGE
  79 #define NR_MASK_WORDS   ((NR_IRQS + 31) / 32)
  80 unsigned long ppc_cached_irq_mask[NR_MASK_WORDS];
  81 #endif
  82
  83 #ifdef CONFIG_TAU_INT
  84 extern int tau_initialized;
  85 extern int tau_interrupts(int);
  86 #endif
  87 #endif /* CONFIG_PPC32 */
  88
  89 #if defined(CONFIG_SMP) && !defined(CONFIG_PPC_MERGE)
  90 extern atomic_t ipi_recv;
  91 extern atomic_t ipi_sent;
  92 #endif
  93
  94 #ifdef CONFIG_PPC64
  95 EXPORT_SYMBOL(irq_desc);
  96
  97 int distribute_irqs = 1;
  98 #endif /* CONFIG_PPC64 */
  99
 100 int show_interrupts(struct seq_file *p, void *v)
 101 {
 102         int i = *(loff_t *)v, j;
 103         struct irqaction *action;
 104         irq_desc_t *desc;
 105         unsigned long flags;
 106
 107         if (i == 0) {
 108                 seq_puts(p, "           ");
 109                 for_each_online_cpu(j)
 110                         seq_printf(p, "CPU%d       ", j);
 111                 seq_putc(p, '\n');
 112         }
 113
 114         if (i < NR_IRQS) {
 115                 desc = get_irq_desc(i);
 116                 spin_lock_irqsave(&desc->lock, flags);
 117                 action = desc->action;
 118                 if (!action || !action->handler)
 119                         goto skip;
 120                 seq_printf(p, "%3d: ", i);
 121 #ifdef CONFIG_SMP
 122                 for_each_online_cpu(j)
 123                         seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
 124 #else
 125                 seq_printf(p, "%10u ", kstat_irqs(i));
 126 #endif /* CONFIG_SMP */
 127                 if (desc->chip)
 128                         seq_printf(p, " %s ", desc->chip->typename);
 129                 else
 130                         seq_puts(p, "  None      ");
 131                 seq_printf(p, "%s", (desc->status & IRQ_LEVEL) ? "Level " : "Edge  ");
 132                 seq_printf(p, "    %s", action->name);
 133                 for (action = action->next; action; action = action->next)
 134                         seq_printf(p, ", %s", action->name);
 135                 seq_putc(p, '\n');
 136 skip:
 137                 spin_unlock_irqrestore(&desc->lock, flags);
 138         } else if (i == NR_IRQS) {
 139 #ifdef CONFIG_PPC32
 140 #ifdef CONFIG_TAU_INT
 141                 if (tau_initialized){
 142                         seq_puts(p, "TAU: ");
 143                         for_each_online_cpu(j)
 144                                 seq_printf(p, "%10u ", tau_interrupts(j));
 145                         seq_puts(p, "  PowerPC             Thermal Assist (cpu temp)\n");
 146                 }
 147 #endif
 148 #if defined(CONFIG_SMP) && !defined(CONFIG_PPC_MERGE)
 149                 /* should this be per processor send/receive? */
 150                 seq_printf(p, "IPI (recv/sent): %10u/%u\n",
 151                                 atomic_read(&ipi_recv), atomic_read(&ipi_sent));
 152 #endif
 153 #endif /* CONFIG_PPC32 */
 154                 seq_printf(p, "BAD: %10u\n", ppc_spurious_interrupts);
 155         }
 156         return 0;
 157 }
 158
 159 #ifdef CONFIG_HOTPLUG_CPU
 160 void fixup_irqs(cpumask_t map)
 161 {
 162         unsigned int irq;
 163         static int warned;
 164
 165         for_each_irq(irq) {
 166                 cpumask_t mask;
 167
 168                 if (irq_desc[irq].status & IRQ_PER_CPU)
 169                         continue;
 170
 171                 cpus_and(mask, irq_desc[irq].affinity, map);
 172                 if (any_online_cpu(mask) == NR_CPUS) {
 173                         printk("Breaking affinity for irq %i\n", irq);
 174                         mask = map;
 175                 }
 176                 if (irq_desc[irq].chip->set_affinity)
 177                         irq_desc[irq].chip->set_affinity(irq, mask);
 178                 else if (irq_desc[irq].action && !(warned++))
 179                         printk("Cannot set affinity for irq %i\n", irq);
 180         }
 181
 182         local_irq_enable();
 183         mdelay(1);
 184         local_irq_disable();
 185 }
 186 #endif
 187
 188 void do_IRQ(struct pt_regs *regs)
 189 {
 190         unsigned int irq;
 191 #ifdef CONFIG_IRQSTACKS
 192         struct thread_info *curtp, *irqtp;
 193 #endif
 194
 195         irq_enter();
 196
 197 #ifdef CONFIG_DEBUG_STACKOVERFLOW
 198         /* Debugging check for stack overflow: is there less than 2KB free? */
 199         {
 200                 long sp;
 201
 202                 sp = __get_SP() & (THREAD_SIZE-1);
 203
 204                 if (unlikely(sp < (sizeof(struct thread_info) + 2048))) {
 205                         printk("do_IRQ: stack overflow: %ld\n",
 206                                 sp - sizeof(struct thread_info));
 207                         dump_stack();
 208                 }
 209         }
 210 #endif
 211
 212         /*
 213          * Every platform is required to implement ppc_md.get_irq.
 214          * This function will either return an irq number or -1 to
 215          * indicate there are no more pending.
 216          * The value -2 is for buggy hardware and means that this IRQ
 217          * has already been handled. -- Tom
 218          */
 219         irq = ppc_md.get_irq(regs);
 220
 221         if (irq != NO_IRQ && irq != NO_IRQ_IGNORE) {
 222 #ifdef CONFIG_IRQSTACKS
 223                 /* Switch to the irq stack to handle this */
 224                 curtp = current_thread_info();
 225                 irqtp = hardirq_ctx[smp_processor_id()];
 226                 if (curtp != irqtp) {
 227                         struct irq_desc *desc = irq_desc + irq;
 228                         void *handler = desc->handle_irq;
 229                         if (handler == NULL)
 230                                 handler = &__do_IRQ;
 231                         irqtp->task = curtp->task;
 232                         irqtp->flags = 0;
 233                         call_handle_irq(irq, desc, regs, irqtp, handler);
 234                         irqtp->task = NULL;
 235                         if (irqtp->flags)
 236                                 set_bits(irqtp->flags, &curtp->flags);
 237                 } else
 238 #endif
 239                         generic_handle_irq(irq, regs);
 240         } else if (irq != NO_IRQ_IGNORE)
 241                 /* That's not SMP safe ... but who cares ? */
 242                 ppc_spurious_interrupts++;
 243
 244         irq_exit();
 245
 246 #ifdef CONFIG_PPC_ISERIES
 247         if (get_lppaca()->int_dword.fields.decr_int) {
 248                 get_lppaca()->int_dword.fields.decr_int = 0;
 249                 /* Signal a fake decrementer interrupt */
 250                 timer_interrupt(regs);
 251         }
 252 #endif
 253 }
 254
 255 void __init init_IRQ(void)
 256 {
 257         ppc_md.init_IRQ();
 258 #ifdef CONFIG_PPC64
 259         irq_ctx_init();
 260 #endif
 261 }
 262
 263
 264 #ifdef CONFIG_IRQSTACKS
 265 struct thread_info *softirq_ctx[NR_CPUS] __read_mostly;
 266 struct thread_info *hardirq_ctx[NR_CPUS] __read_mostly;
 267
 268 void irq_ctx_init(void)
 269 {
 270         struct thread_info *tp;
 271         int i;
 272
 273         for_each_possible_cpu(i) {
 274                 memset((void *)softirq_ctx[i], 0, THREAD_SIZE);
 275                 tp = softirq_ctx[i];
 276                 tp->cpu = i;
 277                 tp->preempt_count = SOFTIRQ_OFFSET;
 278
 279                 memset((void *)hardirq_ctx[i], 0, THREAD_SIZE);
 280                 tp = hardirq_ctx[i];
 281                 tp->cpu = i;
 282                 tp->preempt_count = HARDIRQ_OFFSET;
 283         }
 284 }
 285
 286 static inline void do_softirq_onstack(void)
 287 {
 288         struct thread_info *curtp, *irqtp;
 289
 290         curtp = current_thread_info();
 291         irqtp = softirq_ctx[smp_processor_id()];
 292         irqtp->task = curtp->task;
 293         call_do_softirq(irqtp);
 294         irqtp->task = NULL;
 295 }
 296
 297 #else
 298 #define do_softirq_onstack()    __do_softirq()
 299 #endif /* CONFIG_IRQSTACKS */
 300
 301 void do_softirq(void)
 302 {
 303         unsigned long flags;
 304
 305         if (in_interrupt())
 306                 return;
 307
 308         local_irq_save(flags);
 309
 310         if (local_softirq_pending())
 311                 do_softirq_onstack();
 312
 313         local_irq_restore(flags);
 314 }
 315 EXPORT_SYMBOL(do_softirq);
 316
 317
 318 /*
 319  * IRQ controller and virtual interrupts
 320  */
 321
 322 #ifdef CONFIG_PPC_MERGE
 323
 324 static LIST_HEAD(irq_hosts);
 325 static spinlock_t irq_big_lock = SPIN_LOCK_UNLOCKED;
 326
 327 struct irq_map_entry irq_map[NR_IRQS];
 328 static unsigned int irq_virq_count = NR_IRQS;
 329 static struct irq_host *irq_default_host;
 330
 331 struct irq_host *irq_alloc_host(unsigned int revmap_type,
 332                                 unsigned int revmap_arg,
 333                                 struct irq_host_ops *ops,
 334                                 irq_hw_number_t inval_irq)
 335 {
 336         struct irq_host *host;
 337         unsigned int size = sizeof(struct irq_host);
 338         unsigned int i;
 339         unsigned int *rmap;
 340         unsigned long flags;
 341
 342         /* Allocate structure and revmap table if using linear mapping */
 343         if (revmap_type == IRQ_HOST_MAP_LINEAR)
 344                 size += revmap_arg * sizeof(unsigned int);
 345         if (mem_init_done)
 346                 host = kzalloc(size, GFP_KERNEL);
 347         else {
 348                 host = alloc_bootmem(size);
 349                 if (host)
 350                         memset(host, 0, size);
 351         }
 352         if (host == NULL)
 353                 return NULL;
 354
 355         /* Fill structure */
 356         host->revmap_type = revmap_type;
 357         host->inval_irq = inval_irq;
 358         host->ops = ops;
 359
 360         spin_lock_irqsave(&irq_big_lock, flags);
 361
 362         /* If it's a legacy controller, check for duplicates and
 363          * mark it as allocated (we use irq 0 host pointer for that
 364          */
 365         if (revmap_type == IRQ_HOST_MAP_LEGACY) {
 366                 if (irq_map[0].host != NULL) {
 367                         spin_unlock_irqrestore(&irq_big_lock, flags);
 368                         /* If we are early boot, we can't free the structure,
 369                          * too bad...
 370                          * this will be fixed once slab is made available early
 371                          * instead of the current cruft
 372                          */
 373                         if (mem_init_done)
 374                                 kfree(host);
 375                         return NULL;
 376                 }
 377                 irq_map[0].host = host;
 378         }
 379
 380         list_add(&host->link, &irq_hosts);
 381         spin_unlock_irqrestore(&irq_big_lock, flags);
 382
 383         /* Additional setups per revmap type */
 384         switch(revmap_type) {
 385         case IRQ_HOST_MAP_LEGACY:
 386                 /* 0 is always the invalid number for legacy */
 387                 host->inval_irq = 0;
 388                 /* setup us as the host for all legacy interrupts */
 389                 for (i = 1; i < NUM_ISA_INTERRUPTS; i++) {
 390                         irq_map[i].hwirq = 0;
 391                         smp_wmb();
 392                         irq_map[i].host = host;
 393                         smp_wmb();
 394
 395                         /* Clear norequest flags */
 396                         get_irq_desc(i)->status &= ~IRQ_NOREQUEST;
 397
 398                         /* Legacy flags are left to default at this point,
 399                          * one can then use irq_create_mapping() to
 400                          * explicitely change them
 401                          */
 402                         ops->map(host, i, i);
 403                 }
 404                 break;
 405         case IRQ_HOST_MAP_LINEAR:
 406                 rmap = (unsigned int *)(host + 1);
 407                 for (i = 0; i < revmap_arg; i++)
 408                         rmap[i] = IRQ_NONE;
 409                 host->revmap_data.linear.size = revmap_arg;
 410                 smp_wmb();
 411                 host->revmap_data.linear.revmap = rmap;
 412                 break;
 413         default:
 414                 break;
 415         }
 416
 417         pr_debug("irq: Allocated host of type %d @0x%p\n", revmap_type, host);
 418
 419         return host;
 420 }
 421
 422 struct irq_host *irq_find_host(struct device_node *node)
 423 {
 424         struct irq_host *h, *found = NULL;
 425         unsigned long flags;
 426
 427         /* We might want to match the legacy controller last since
 428          * it might potentially be set to match all interrupts in
 429          * the absence of a device node. This isn't a problem so far
 430          * yet though...
 431          */
 432         spin_lock_irqsave(&irq_big_lock, flags);
 433         list_for_each_entry(h, &irq_hosts, link)
 434                 if (h->ops->match == NULL || h->ops->match(h, node)) {
 435                         found = h;
 436                         break;
 437                 }
 438         spin_unlock_irqrestore(&irq_big_lock, flags);
 439         return found;
 440 }
 441 EXPORT_SYMBOL_GPL(irq_find_host);
 442
 443 void irq_set_default_host(struct irq_host *host)
 444 {
 445         pr_debug("irq: Default host set to @0x%p\n", host);
 446
 447         irq_default_host = host;
 448 }
 449
 450 void irq_set_virq_count(unsigned int count)
 451 {
 452         pr_debug("irq: Trying to set virq count to %d\n", count);
 453
 454         BUG_ON(count < NUM_ISA_INTERRUPTS);
 455         if (count < NR_IRQS)
 456                 irq_virq_count = count;
 457 }
 458
 459 unsigned int irq_create_mapping(struct irq_host *host,
 460                                 irq_hw_number_t hwirq)
 461 {
 462         unsigned int virq, hint;
 463
 464         pr_debug("irq: irq_create_mapping(0x%p, 0x%lx)\n", host, hwirq);
 465
 466         /* Look for default host if nececssary */
 467         if (host == NULL)
 468                 host = irq_default_host;
 469         if (host == NULL) {
 470                 printk(KERN_WARNING "irq_create_mapping called for"
 471                        " NULL host, hwirq=%lx\n", hwirq);
 472                 WARN_ON(1);
 473                 return NO_IRQ;
 474         }
 475         pr_debug("irq: -> using host @%p\n", host);
 476
 477         /* Check if mapping already exist, if it does, call
 478          * host->ops->map() to update the flags
 479          */
 480         virq = irq_find_mapping(host, hwirq);
 481         if (virq != IRQ_NONE) {
 482                 pr_debug("irq: -> existing mapping on virq %d\n", virq);
 483                 return virq;
 484         }
 485
 486         /* Get a virtual interrupt number */
 487         if (host->revmap_type == IRQ_HOST_MAP_LEGACY) {
 488                 /* Handle legacy */
 489                 virq = (unsigned int)hwirq;
 490                 if (virq == 0 || virq >= NUM_ISA_INTERRUPTS)
 491                         return NO_IRQ;
 492                 return virq;
 493         } else {
 494                 /* Allocate a virtual interrupt number */
 495                 hint = hwirq % irq_virq_count;
 496                 virq = irq_alloc_virt(host, 1, hint);
 497                 if (virq == NO_IRQ) {
 498                         pr_debug("irq: -> virq allocation failed\n");
 499                         return NO_IRQ;
 500                 }
 501         }
 502         pr_debug("irq: -> obtained virq %d\n", virq);
 503
 504         /* Clear IRQ_NOREQUEST flag */
 505         get_irq_desc(virq)->status &= ~IRQ_NOREQUEST;
 506
 507         /* map it */
 508         smp_wmb();
 509         irq_map[virq].hwirq = hwirq;
 510         smp_mb();
 511         if (host->ops->map(host, virq, hwirq)) {
 512                 pr_debug("irq: -> mapping failed, freeing\n");
 513                 irq_free_virt(virq, 1);
 514                 return NO_IRQ;
 515         }
 516         return virq;
 517 }
 518 EXPORT_SYMBOL_GPL(irq_create_mapping);
 519
 520 extern unsigned int irq_create_of_mapping(struct device_node *controller,
 521                                           u32 *intspec, unsigned int intsize)
 522 {
 523         struct irq_host *host;
 524         irq_hw_number_t hwirq;
 525         unsigned int type = IRQ_TYPE_NONE;
 526         unsigned int virq;
 527
 528         if (controller == NULL)
 529                 host = irq_default_host;
 530         else
 531                 host = irq_find_host(controller);
 532         if (host == NULL) {
 533                 printk(KERN_WARNING "irq: no irq host found for %s !\n",
 534                        controller->full_name);
 535                 return NO_IRQ;
 536         }
 537
 538         /* If host has no translation, then we assume interrupt line */
 539         if (host->ops->xlate == NULL)
 540                 hwirq = intspec[0];
 541         else {
 542                 if (host->ops->xlate(host, controller, intspec, intsize,
 543                                      &hwirq, &type))
 544                         return NO_IRQ;
 545         }
 546
 547         /* Create mapping */
 548         virq = irq_create_mapping(host, hwirq);
 549         if (virq == NO_IRQ)
 550                 return virq;
 551
 552         /* Set type if specified and different than the current one */
 553         if (type != IRQ_TYPE_NONE &&
 554             type != (get_irq_desc(virq)->status & IRQF_TRIGGER_MASK))
 555                 set_irq_type(virq, type);
 556         return virq;
 557 }
 558 EXPORT_SYMBOL_GPL(irq_create_of_mapping);
 559
 560 unsigned int irq_of_parse_and_map(struct device_node *dev, int index)
 561 {
 562         struct of_irq oirq;
 563
 564         if (of_irq_map_one(dev, index, &oirq))
 565                 return NO_IRQ;
 566
 567         return irq_create_of_mapping(oirq.controller, oirq.specifier,
 568                                      oirq.size);
 569 }
 570 EXPORT_SYMBOL_GPL(irq_of_parse_and_map);
 571
 572 void irq_dispose_mapping(unsigned int virq)
 573 {
 574         struct irq_host *host = irq_map[virq].host;
 575         irq_hw_number_t hwirq;
 576         unsigned long flags;
 577
 578         WARN_ON (host == NULL);
 579         if (host == NULL)
 580                 return;
 581
 582         /* Never unmap legacy interrupts */
 583         if (host->revmap_type == IRQ_HOST_MAP_LEGACY)
 584                 return;
 585
 586         /* remove chip and handler */
 587         set_irq_chip_and_handler(virq, NULL, NULL);
 588
 589         /* Make sure it's completed */
 590         synchronize_irq(virq);
 591
 592         /* Tell the PIC about it */
 593         if (host->ops->unmap)
 594                 host->ops->unmap(host, virq);
 595         smp_mb();
 596
 597         /* Clear reverse map */
 598         hwirq = irq_map[virq].hwirq;
 599         switch(host->revmap_type) {
 600         case IRQ_HOST_MAP_LINEAR:
 601                 if (hwirq < host->revmap_data.linear.size)
 602                         host->revmap_data.linear.revmap[hwirq] = IRQ_NONE;
 603                 break;
 604         case IRQ_HOST_MAP_TREE:
 605                 /* Check if radix tree allocated yet */
 606                 if (host->revmap_data.tree.gfp_mask == 0)
 607                         break;
 608                 /* XXX radix tree not safe ! remove lock whem it becomes safe
 609                  * and use some RCU sync to make sure everything is ok before we
 610                  * can re-use that map entry
 611                  */
 612                 spin_lock_irqsave(&irq_big_lock, flags);
 613                 radix_tree_delete(&host->revmap_data.tree, hwirq);
 614                 spin_unlock_irqrestore(&irq_big_lock, flags);
 615                 break;
 616         }
 617
 618         /* Destroy map */
 619         smp_mb();
 620         irq_map[virq].hwirq = host->inval_irq;
 621
 622         /* Set some flags */
 623         get_irq_desc(virq)->status |= IRQ_NOREQUEST;
 624
 625         /* Free it */
 626         irq_free_virt(virq, 1);
 627 }
 628 EXPORT_SYMBOL_GPL(irq_dispose_mapping);
 629
 630 unsigned int irq_find_mapping(struct irq_host *host,
 631                               irq_hw_number_t hwirq)
 632 {
 633         unsigned int i;
 634         unsigned int hint = hwirq % irq_virq_count;
 635
 636         /* Look for default host if nececssary */
 637         if (host == NULL)
 638                 host = irq_default_host;
 639         if (host == NULL)
 640                 return NO_IRQ;
 641
 642         /* legacy -> bail early */
 643         if (host->revmap_type == IRQ_HOST_MAP_LEGACY)
 644                 return hwirq;
 645
 646         /* Slow path does a linear search of the map */
 647         if (hint < NUM_ISA_INTERRUPTS)
 648                 hint = NUM_ISA_INTERRUPTS;
 649         i = hint;
 650         do  {
 651                 if (irq_map[i].host == host &&
 652                     irq_map[i].hwirq == hwirq)
 653                         return i;
 654                 i++;
 655                 if (i >= irq_virq_count)
 656                         i = NUM_ISA_INTERRUPTS;
 657         } while(i != hint);
 658         return NO_IRQ;
 659 }
 660 EXPORT_SYMBOL_GPL(irq_find_mapping);
 661
 662
 663 unsigned int irq_radix_revmap(struct irq_host *host,
 664                               irq_hw_number_t hwirq)
 665 {
 666         struct radix_tree_root *tree;
 667         struct irq_map_entry *ptr;
 668         unsigned int virq;
 669         unsigned long flags;
 670
 671         WARN_ON(host->revmap_type != IRQ_HOST_MAP_TREE);
 672
 673         /* Check if the radix tree exist yet. We test the value of
 674          * the gfp_mask for that. Sneaky but saves another int in the
 675          * structure. If not, we fallback to slow mode
 676          */
 677         tree = &host->revmap_data.tree;
 678         if (tree->gfp_mask == 0)
 679                 return irq_find_mapping(host, hwirq);
 680
 681         /* XXX Current radix trees are NOT SMP safe !!! Remove that lock
 682          * when that is fixed (when Nick's patch gets in
 683          */
 684         spin_lock_irqsave(&irq_big_lock, flags);
 685
 686         /* Now try to resolve */
 687         ptr = radix_tree_lookup(tree, hwirq);
 688         /* Found it, return */
 689         if (ptr) {
 690                 virq = ptr - irq_map;
 691                 goto bail;
 692         }
 693
 694         /* If not there, try to insert it */
 695         virq = irq_find_mapping(host, hwirq);
 696         if (virq != NO_IRQ)
 697                 radix_tree_insert(tree, virq, &irq_map[virq]);
 698  bail:
 699         spin_unlock_irqrestore(&irq_big_lock, flags);
 700         return virq;
 701 }
 702
 703 unsigned int irq_linear_revmap(struct irq_host *host,
 704                                irq_hw_number_t hwirq)
 705 {
 706         unsigned int *revmap;
 707
 708         WARN_ON(host->revmap_type != IRQ_HOST_MAP_LINEAR);
 709
 710         /* Check revmap bounds */
 711         if (unlikely(hwirq >= host->revmap_data.linear.size))
 712                 return irq_find_mapping(host, hwirq);
 713
 714         /* Check if revmap was allocated */
 715         revmap = host->revmap_data.linear.revmap;
 716         if (unlikely(revmap == NULL))
 717                 return irq_find_mapping(host, hwirq);
 718
 719         /* Fill up revmap with slow path if no mapping found */
 720         if (unlikely(revmap[hwirq] == NO_IRQ))
 721                 revmap[hwirq] = irq_find_mapping(host, hwirq);
 722
 723         return revmap[hwirq];
 724 }
 725
 726 unsigned int irq_alloc_virt(struct irq_host *host,
 727                             unsigned int count,
 728                             unsigned int hint)
 729 {
 730         unsigned long flags;
 731         unsigned int i, j, found = NO_IRQ;
 732         unsigned int limit = irq_virq_count - count;
 733
 734         if (count == 0 || count > (irq_virq_count - NUM_ISA_INTERRUPTS))
 735                 return NO_IRQ;
 736
 737         spin_lock_irqsave(&irq_big_lock, flags);
 738
 739         /* Use hint for 1 interrupt if any */
 740         if (count == 1 && hint >= NUM_ISA_INTERRUPTS &&
 741             hint < irq_virq_count && irq_map[hint].host == NULL) {
 742                 found = hint;
 743                 goto hint_found;
 744         }
 745
 746         /* Look for count consecutive numbers in the allocatable
 747          * (non-legacy) space
 748          */
 749         for (i = NUM_ISA_INTERRUPTS; i <= limit; ) {
 750                 for (j = i; j < (i + count); j++)
 751                         if (irq_map[j].host != NULL) {
 752                                 i = j + 1;
 753                                 continue;
 754                         }
 755                 found = i;
 756                 break;
 757         }
 758         if (found == NO_IRQ) {
 759                 spin_unlock_irqrestore(&irq_big_lock, flags);
 760                 return NO_IRQ;
 761         }
 762  hint_found:
 763         for (i = found; i < (found + count); i++) {
 764                 irq_map[i].hwirq = host->inval_irq;
 765                 smp_wmb();
 766                 irq_map[i].host = host;
 767         }
 768         spin_unlock_irqrestore(&irq_big_lock, flags);
 769         return found;
 770 }
 771
 772 void irq_free_virt(unsigned int virq, unsigned int count)
 773 {
 774         unsigned long flags;
 775         unsigned int i;
 776
 777         WARN_ON (virq < NUM_ISA_INTERRUPTS);
 778         WARN_ON (count == 0 || (virq + count) > irq_virq_count);
 779
 780         spin_lock_irqsave(&irq_big_lock, flags);
 781         for (i = virq; i < (virq + count); i++) {
 782                 struct irq_host *host;
 783
 784                 if (i < NUM_ISA_INTERRUPTS ||
 785                     (virq + count) > irq_virq_count)
 786                         continue;
 787
 788                 host = irq_map[i].host;
 789                 irq_map[i].hwirq = host->inval_irq;
 790                 smp_wmb();
 791                 irq_map[i].host = NULL;
 792         }
 793         spin_unlock_irqrestore(&irq_big_lock, flags);
 794 }
 795
 796 void irq_early_init(void)
 797 {
 798         unsigned int i;
 799
 800         for (i = 0; i < NR_IRQS; i++)
 801                 get_irq_desc(i)->status |= IRQ_NOREQUEST;
 802 }
 803
 804 /* We need to create the radix trees late */
 805 static int irq_late_init(void)
 806 {
 807         struct irq_host *h;
 808         unsigned long flags;
 809
 810         spin_lock_irqsave(&irq_big_lock, flags);
 811         list_for_each_entry(h, &irq_hosts, link) {
 812                 if (h->revmap_type == IRQ_HOST_MAP_TREE)
 813                         INIT_RADIX_TREE(&h->revmap_data.tree, GFP_ATOMIC);
 814         }
 815         spin_unlock_irqrestore(&irq_big_lock, flags);
 816
 817         return 0;
 818 }
 819 arch_initcall(irq_late_init);
 820
 821 #endif /* CONFIG_PPC_MERGE */
 822
 823 #ifdef CONFIG_PCI_MSI
 824 int pci_enable_msi(struct pci_dev * pdev)
 825 {
 826         if (ppc_md.enable_msi)
 827                 return ppc_md.enable_msi(pdev);
 828         else
 829                 return -1;
 830 }
 831 EXPORT_SYMBOL(pci_enable_msi);
 832
 833 void pci_disable_msi(struct pci_dev * pdev)
 834 {
 835         if (ppc_md.disable_msi)
 836                 ppc_md.disable_msi(pdev);
 837 }
 838 EXPORT_SYMBOL(pci_disable_msi);
 839
 840 void pci_scan_msi_device(struct pci_dev *dev) {}
 841 int pci_enable_msix(struct pci_dev* dev, struct msix_entry *entries, int nvec) {return -1;}
 842 void pci_disable_msix(struct pci_dev *dev) {}
 843 void msi_remove_pci_irq_vectors(struct pci_dev *dev) {}
 844 void disable_msi_mode(struct pci_dev *dev, int pos, int type) {}
 845 void pci_no_msi(void) {}
 846 EXPORT_SYMBOL(pci_enable_msix);
 847 EXPORT_SYMBOL(pci_disable_msix);
 848
 849 #endif
 850
 851 #ifdef CONFIG_PPC64
 852 static int __init setup_noirqdistrib(char *str)
 853 {
 854         distribute_irqs = 0;
 855         return 1;
 856 }
 857
 858 __setup("noirqdistrib", setup_noirqdistrib);
 859 #endif /* CONFIG_PPC64 */