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/vs_context.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                 struct vx_info_save vxis;
 223
 224                 __enter_vx_admin(&vxis);
 225 #ifdef CONFIG_IRQSTACKS
 226                 /* Switch to the irq stack to handle this */
 227                 curtp = current_thread_info();
 228                 irqtp = hardirq_ctx[smp_processor_id()];
 229                 if (curtp != irqtp) {
 230                         struct irq_desc *desc = irq_desc + irq;
 231                         void *handler = desc->handle_irq;
 232                         if (handler == NULL)
 233                                 handler = &__do_IRQ;
 234                         irqtp->task = curtp->task;
 235                         irqtp->flags = 0;
 236                         call_handle_irq(irq, desc, regs, irqtp, handler);
 237                         irqtp->task = NULL;
 238                         if (irqtp->flags)
 239                                 set_bits(irqtp->flags, &curtp->flags);
 240                 } else
 241 #endif
 242                         generic_handle_irq(irq, regs);
 243                 __leave_vx_admin(&vxis);
 244         } else if (irq != NO_IRQ_IGNORE)
 245                 /* That's not SMP safe ... but who cares ? */
 246                 ppc_spurious_interrupts++;
 247
 248         irq_exit();
 249
 250 #ifdef CONFIG_PPC_ISERIES
 251         if (get_lppaca()->int_dword.fields.decr_int) {
 252
 253                 get_lppaca()->int_dword.fields.decr_int = 0;
 254                 /* Signal a fake decrementer interrupt */
 255                 timer_interrupt(regs);
 256         }
 257 #endif
 258 }
 259
 260 void __init init_IRQ(void)
 261 {
 262         ppc_md.init_IRQ();
 263 #ifdef CONFIG_PPC64
 264         irq_ctx_init();
 265 #endif
 266 }
 267
 268
 269 #ifdef CONFIG_IRQSTACKS
 270 struct thread_info *softirq_ctx[NR_CPUS] __read_mostly;
 271 struct thread_info *hardirq_ctx[NR_CPUS] __read_mostly;
 272
 273 void irq_ctx_init(void)
 274 {
 275         struct thread_info *tp;
 276         int i;
 277
 278         for_each_possible_cpu(i) {
 279                 memset((void *)softirq_ctx[i], 0, THREAD_SIZE);
 280                 tp = softirq_ctx[i];
 281                 tp->cpu = i;
 282                 tp->preempt_count = SOFTIRQ_OFFSET;
 283
 284                 memset((void *)hardirq_ctx[i], 0, THREAD_SIZE);
 285                 tp = hardirq_ctx[i];
 286                 tp->cpu = i;
 287                 tp->preempt_count = HARDIRQ_OFFSET;
 288         }
 289 }
 290
 291 static inline void do_softirq_onstack(void)
 292 {
 293         struct thread_info *curtp, *irqtp;
 294
 295         curtp = current_thread_info();
 296         irqtp = softirq_ctx[smp_processor_id()];
 297         irqtp->task = curtp->task;
 298         call_do_softirq(irqtp);
 299         irqtp->task = NULL;
 300 }
 301
 302 #else
 303 #define do_softirq_onstack()    __do_softirq()
 304 #endif /* CONFIG_IRQSTACKS */
 305
 306 void do_softirq(void)
 307 {
 308         unsigned long flags;
 309
 310         if (in_interrupt())
 311                 return;
 312
 313         local_irq_save(flags);
 314
 315         if (local_softirq_pending())
 316                 do_softirq_onstack();
 317
 318         local_irq_restore(flags);
 319 }
 320 EXPORT_SYMBOL(do_softirq);
 321
 322
 323 /*
 324  * IRQ controller and virtual interrupts
 325  */
 326
 327 #ifdef CONFIG_PPC_MERGE
 328
 329 static LIST_HEAD(irq_hosts);
 330 static spinlock_t irq_big_lock = SPIN_LOCK_UNLOCKED;
 331 static DEFINE_PER_CPU(unsigned int, irq_radix_reader);
 332 static unsigned int irq_radix_writer;
 333 struct irq_map_entry irq_map[NR_IRQS];
 334 static unsigned int irq_virq_count = NR_IRQS;
 335 static struct irq_host *irq_default_host;
 336
 337 struct irq_host *irq_alloc_host(unsigned int revmap_type,
 338                                 unsigned int revmap_arg,
 339                                 struct irq_host_ops *ops,
 340                                 irq_hw_number_t inval_irq)
 341 {
 342         struct irq_host *host;
 343         unsigned int size = sizeof(struct irq_host);
 344         unsigned int i;
 345         unsigned int *rmap;
 346         unsigned long flags;
 347
 348         /* Allocate structure and revmap table if using linear mapping */
 349         if (revmap_type == IRQ_HOST_MAP_LINEAR)
 350                 size += revmap_arg * sizeof(unsigned int);
 351         if (mem_init_done)
 352                 host = kzalloc(size, GFP_KERNEL);
 353         else {
 354                 host = alloc_bootmem(size);
 355                 if (host)
 356                         memset(host, 0, size);
 357         }
 358         if (host == NULL)
 359                 return NULL;
 360
 361         /* Fill structure */
 362         host->revmap_type = revmap_type;
 363         host->inval_irq = inval_irq;
 364         host->ops = ops;
 365
 366         spin_lock_irqsave(&irq_big_lock, flags);
 367
 368         /* If it's a legacy controller, check for duplicates and
 369          * mark it as allocated (we use irq 0 host pointer for that
 370          */
 371         if (revmap_type == IRQ_HOST_MAP_LEGACY) {
 372                 if (irq_map[0].host != NULL) {
 373                         spin_unlock_irqrestore(&irq_big_lock, flags);
 374                         /* If we are early boot, we can't free the structure,
 375                          * too bad...
 376                          * this will be fixed once slab is made available early
 377                          * instead of the current cruft
 378                          */
 379                         if (mem_init_done)
 380                                 kfree(host);
 381                         return NULL;
 382                 }
 383                 irq_map[0].host = host;
 384         }
 385
 386         list_add(&host->link, &irq_hosts);
 387         spin_unlock_irqrestore(&irq_big_lock, flags);
 388
 389         /* Additional setups per revmap type */
 390         switch(revmap_type) {
 391         case IRQ_HOST_MAP_LEGACY:
 392                 /* 0 is always the invalid number for legacy */
 393                 host->inval_irq = 0;
 394                 /* setup us as the host for all legacy interrupts */
 395                 for (i = 1; i < NUM_ISA_INTERRUPTS; i++) {
 396                         irq_map[i].hwirq = 0;
 397                         smp_wmb();
 398                         irq_map[i].host = host;
 399                         smp_wmb();
 400
 401                         /* Clear norequest flags */
 402                         get_irq_desc(i)->status &= ~IRQ_NOREQUEST;
 403
 404                         /* Legacy flags are left to default at this point,
 405                          * one can then use irq_create_mapping() to
 406                          * explicitely change them
 407                          */
 408                         ops->map(host, i, i);
 409                 }
 410                 break;
 411         case IRQ_HOST_MAP_LINEAR:
 412                 rmap = (unsigned int *)(host + 1);
 413                 for (i = 0; i < revmap_arg; i++)
 414                         rmap[i] = IRQ_NONE;
 415                 host->revmap_data.linear.size = revmap_arg;
 416                 smp_wmb();
 417                 host->revmap_data.linear.revmap = rmap;
 418                 break;
 419         default:
 420                 break;
 421         }
 422
 423         pr_debug("irq: Allocated host of type %d @0x%p\n", revmap_type, host);
 424
 425         return host;
 426 }
 427
 428 struct irq_host *irq_find_host(struct device_node *node)
 429 {
 430         struct irq_host *h, *found = NULL;
 431         unsigned long flags;
 432
 433         /* We might want to match the legacy controller last since
 434          * it might potentially be set to match all interrupts in
 435          * the absence of a device node. This isn't a problem so far
 436          * yet though...
 437          */
 438         spin_lock_irqsave(&irq_big_lock, flags);
 439         list_for_each_entry(h, &irq_hosts, link)
 440                 if (h->ops->match == NULL || h->ops->match(h, node)) {
 441                         found = h;
 442                         break;
 443                 }
 444         spin_unlock_irqrestore(&irq_big_lock, flags);
 445         return found;
 446 }
 447 EXPORT_SYMBOL_GPL(irq_find_host);
 448
 449 void irq_set_default_host(struct irq_host *host)
 450 {
 451         pr_debug("irq: Default host set to @0x%p\n", host);
 452
 453         irq_default_host = host;
 454 }
 455
 456 void irq_set_virq_count(unsigned int count)
 457 {
 458         pr_debug("irq: Trying to set virq count to %d\n", count);
 459
 460         BUG_ON(count < NUM_ISA_INTERRUPTS);
 461         if (count < NR_IRQS)
 462                 irq_virq_count = count;
 463 }
 464
 465 /* radix tree not lockless safe ! we use a brlock-type mecanism
 466  * for now, until we can use a lockless radix tree
 467  */
 468 static void irq_radix_wrlock(unsigned long *flags)
 469 {
 470         unsigned int cpu, ok;
 471
 472         spin_lock_irqsave(&irq_big_lock, *flags);
 473         irq_radix_writer = 1;
 474         smp_mb();
 475         do {
 476                 barrier();
 477                 ok = 1;
 478                 for_each_possible_cpu(cpu) {
 479                         if (per_cpu(irq_radix_reader, cpu)) {
 480                                 ok = 0;
 481                                 break;
 482                         }
 483                 }
 484                 if (!ok)
 485                         cpu_relax();
 486         } while(!ok);
 487 }
 488
 489 static void irq_radix_wrunlock(unsigned long flags)
 490 {
 491         smp_wmb();
 492         irq_radix_writer = 0;
 493         spin_unlock_irqrestore(&irq_big_lock, flags);
 494 }
 495
 496 static void irq_radix_rdlock(unsigned long *flags)
 497 {
 498         local_irq_save(*flags);
 499         __get_cpu_var(irq_radix_reader) = 1;
 500         smp_mb();
 501         if (likely(irq_radix_writer == 0))
 502                 return;
 503         __get_cpu_var(irq_radix_reader) = 0;
 504         smp_wmb();
 505         spin_lock(&irq_big_lock);
 506         __get_cpu_var(irq_radix_reader) = 1;
 507         spin_unlock(&irq_big_lock);
 508 }
 509
 510 static void irq_radix_rdunlock(unsigned long flags)
 511 {
 512         __get_cpu_var(irq_radix_reader) = 0;
 513         local_irq_restore(flags);
 514 }
 515
 516
 517 unsigned int irq_create_mapping(struct irq_host *host,
 518                                 irq_hw_number_t hwirq)
 519 {
 520         unsigned int virq, hint;
 521
 522         pr_debug("irq: irq_create_mapping(0x%p, 0x%lx)\n", host, hwirq);
 523
 524         /* Look for default host if nececssary */
 525         if (host == NULL)
 526                 host = irq_default_host;
 527         if (host == NULL) {
 528                 printk(KERN_WARNING "irq_create_mapping called for"
 529                        " NULL host, hwirq=%lx\n", hwirq);
 530                 WARN_ON(1);
 531                 return NO_IRQ;
 532         }
 533         pr_debug("irq: -> using host @%p\n", host);
 534
 535         /* Check if mapping already exist, if it does, call
 536          * host->ops->map() to update the flags
 537          */
 538         virq = irq_find_mapping(host, hwirq);
 539         if (virq != IRQ_NONE) {
 540                 pr_debug("irq: -> existing mapping on virq %d\n", virq);
 541                 return virq;
 542         }
 543
 544         /* Get a virtual interrupt number */
 545         if (host->revmap_type == IRQ_HOST_MAP_LEGACY) {
 546                 /* Handle legacy */
 547                 virq = (unsigned int)hwirq;
 548                 if (virq == 0 || virq >= NUM_ISA_INTERRUPTS)
 549                         return NO_IRQ;
 550                 return virq;
 551         } else {
 552                 /* Allocate a virtual interrupt number */
 553                 hint = hwirq % irq_virq_count;
 554                 virq = irq_alloc_virt(host, 1, hint);
 555                 if (virq == NO_IRQ) {
 556                         pr_debug("irq: -> virq allocation failed\n");
 557                         return NO_IRQ;
 558                 }
 559         }
 560         pr_debug("irq: -> obtained virq %d\n", virq);
 561
 562         /* Clear IRQ_NOREQUEST flag */
 563         get_irq_desc(virq)->status &= ~IRQ_NOREQUEST;
 564
 565         /* map it */
 566         smp_wmb();
 567         irq_map[virq].hwirq = hwirq;
 568         smp_mb();
 569         if (host->ops->map(host, virq, hwirq)) {
 570                 pr_debug("irq: -> mapping failed, freeing\n");
 571                 irq_free_virt(virq, 1);
 572                 return NO_IRQ;
 573         }
 574         return virq;
 575 }
 576 EXPORT_SYMBOL_GPL(irq_create_mapping);
 577
 578 extern unsigned int irq_create_of_mapping(struct device_node *controller,
 579                                           u32 *intspec, unsigned int intsize)
 580 {
 581         struct irq_host *host;
 582         irq_hw_number_t hwirq;
 583         unsigned int type = IRQ_TYPE_NONE;
 584         unsigned int virq;
 585
 586         if (controller == NULL)
 587                 host = irq_default_host;
 588         else
 589                 host = irq_find_host(controller);
 590         if (host == NULL) {
 591                 printk(KERN_WARNING "irq: no irq host found for %s !\n",
 592                        controller->full_name);
 593                 return NO_IRQ;
 594         }
 595
 596         /* If host has no translation, then we assume interrupt line */
 597         if (host->ops->xlate == NULL)
 598                 hwirq = intspec[0];
 599         else {
 600                 if (host->ops->xlate(host, controller, intspec, intsize,
 601                                      &hwirq, &type))
 602                         return NO_IRQ;
 603         }
 604
 605         /* Create mapping */
 606         virq = irq_create_mapping(host, hwirq);
 607         if (virq == NO_IRQ)
 608                 return virq;
 609
 610         /* Set type if specified and different than the current one */
 611         if (type != IRQ_TYPE_NONE &&
 612             type != (get_irq_desc(virq)->status & IRQF_TRIGGER_MASK))
 613                 set_irq_type(virq, type);
 614         return virq;
 615 }
 616 EXPORT_SYMBOL_GPL(irq_create_of_mapping);
 617
 618 unsigned int irq_of_parse_and_map(struct device_node *dev, int index)
 619 {
 620         struct of_irq oirq;
 621
 622         if (of_irq_map_one(dev, index, &oirq))
 623                 return NO_IRQ;
 624
 625         return irq_create_of_mapping(oirq.controller, oirq.specifier,
 626                                      oirq.size);
 627 }
 628 EXPORT_SYMBOL_GPL(irq_of_parse_and_map);
 629
 630 void irq_dispose_mapping(unsigned int virq)
 631 {
 632         struct irq_host *host = irq_map[virq].host;
 633         irq_hw_number_t hwirq;
 634         unsigned long flags;
 635
 636         WARN_ON (host == NULL);
 637         if (host == NULL)
 638                 return;
 639
 640         /* Never unmap legacy interrupts */
 641         if (host->revmap_type == IRQ_HOST_MAP_LEGACY)
 642                 return;
 643
 644         /* remove chip and handler */
 645         set_irq_chip_and_handler(virq, NULL, NULL);
 646
 647         /* Make sure it's completed */
 648         synchronize_irq(virq);
 649
 650         /* Tell the PIC about it */
 651         if (host->ops->unmap)
 652                 host->ops->unmap(host, virq);
 653         smp_mb();
 654
 655         /* Clear reverse map */
 656         hwirq = irq_map[virq].hwirq;
 657         switch(host->revmap_type) {
 658         case IRQ_HOST_MAP_LINEAR:
 659                 if (hwirq < host->revmap_data.linear.size)
 660                         host->revmap_data.linear.revmap[hwirq] = IRQ_NONE;
 661                 break;
 662         case IRQ_HOST_MAP_TREE:
 663                 /* Check if radix tree allocated yet */
 664                 if (host->revmap_data.tree.gfp_mask == 0)
 665                         break;
 666                 irq_radix_wrlock(&flags);
 667                 radix_tree_delete(&host->revmap_data.tree, hwirq);
 668                 irq_radix_wrunlock(flags);
 669                 break;
 670         }
 671
 672         /* Destroy map */
 673         smp_mb();
 674         irq_map[virq].hwirq = host->inval_irq;
 675
 676         /* Set some flags */
 677         get_irq_desc(virq)->status |= IRQ_NOREQUEST;
 678
 679         /* Free it */
 680         irq_free_virt(virq, 1);
 681 }
 682 EXPORT_SYMBOL_GPL(irq_dispose_mapping);
 683
 684 unsigned int irq_find_mapping(struct irq_host *host,
 685                               irq_hw_number_t hwirq)
 686 {
 687         unsigned int i;
 688         unsigned int hint = hwirq % irq_virq_count;
 689
 690         /* Look for default host if nececssary */
 691         if (host == NULL)
 692                 host = irq_default_host;
 693         if (host == NULL)
 694                 return NO_IRQ;
 695
 696         /* legacy -> bail early */
 697         if (host->revmap_type == IRQ_HOST_MAP_LEGACY)
 698                 return hwirq;
 699
 700         /* Slow path does a linear search of the map */
 701         if (hint < NUM_ISA_INTERRUPTS)
 702                 hint = NUM_ISA_INTERRUPTS;
 703         i = hint;
 704         do  {
 705                 if (irq_map[i].host == host &&
 706                     irq_map[i].hwirq == hwirq)
 707                         return i;
 708                 i++;
 709                 if (i >= irq_virq_count)
 710                         i = NUM_ISA_INTERRUPTS;
 711         } while(i != hint);
 712         return NO_IRQ;
 713 }
 714 EXPORT_SYMBOL_GPL(irq_find_mapping);
 715
 716
 717 unsigned int irq_radix_revmap(struct irq_host *host,
 718                               irq_hw_number_t hwirq)
 719 {
 720         struct radix_tree_root *tree;
 721         struct irq_map_entry *ptr;
 722         unsigned int virq;
 723         unsigned long flags;
 724
 725         WARN_ON(host->revmap_type != IRQ_HOST_MAP_TREE);
 726
 727         /* Check if the radix tree exist yet. We test the value of
 728          * the gfp_mask for that. Sneaky but saves another int in the
 729          * structure. If not, we fallback to slow mode
 730          */
 731         tree = &host->revmap_data.tree;
 732         if (tree->gfp_mask == 0)
 733                 return irq_find_mapping(host, hwirq);
 734
 735         /* Now try to resolve */
 736         irq_radix_rdlock(&flags);
 737         ptr = radix_tree_lookup(tree, hwirq);
 738         irq_radix_rdunlock(flags);
 739
 740         /* Found it, return */
 741         if (ptr) {
 742                 virq = ptr - irq_map;
 743                 return virq;
 744         }
 745
 746         /* If not there, try to insert it */
 747         virq = irq_find_mapping(host, hwirq);
 748         if (virq != NO_IRQ) {
 749                 irq_radix_wrlock(&flags);
 750                 radix_tree_insert(tree, hwirq, &irq_map[virq]);
 751                 irq_radix_wrunlock(flags);
 752         }
 753         return virq;
 754 }
 755
 756 unsigned int irq_linear_revmap(struct irq_host *host,
 757                                irq_hw_number_t hwirq)
 758 {
 759         unsigned int *revmap;
 760
 761         WARN_ON(host->revmap_type != IRQ_HOST_MAP_LINEAR);
 762
 763         /* Check revmap bounds */
 764         if (unlikely(hwirq >= host->revmap_data.linear.size))
 765                 return irq_find_mapping(host, hwirq);
 766
 767         /* Check if revmap was allocated */
 768         revmap = host->revmap_data.linear.revmap;
 769         if (unlikely(revmap == NULL))
 770                 return irq_find_mapping(host, hwirq);
 771
 772         /* Fill up revmap with slow path if no mapping found */
 773         if (unlikely(revmap[hwirq] == NO_IRQ))
 774                 revmap[hwirq] = irq_find_mapping(host, hwirq);
 775
 776         return revmap[hwirq];
 777 }
 778
 779 unsigned int irq_alloc_virt(struct irq_host *host,
 780                             unsigned int count,
 781                             unsigned int hint)
 782 {
 783         unsigned long flags;
 784         unsigned int i, j, found = NO_IRQ;
 785         unsigned int limit = irq_virq_count - count;
 786
 787         if (count == 0 || count > (irq_virq_count - NUM_ISA_INTERRUPTS))
 788                 return NO_IRQ;
 789
 790         spin_lock_irqsave(&irq_big_lock, flags);
 791
 792         /* Use hint for 1 interrupt if any */
 793         if (count == 1 && hint >= NUM_ISA_INTERRUPTS &&
 794             hint < irq_virq_count && irq_map[hint].host == NULL) {
 795                 found = hint;
 796                 goto hint_found;
 797         }
 798
 799         /* Look for count consecutive numbers in the allocatable
 800          * (non-legacy) space
 801          */
 802         for (i = NUM_ISA_INTERRUPTS; i <= limit; ) {
 803                 for (j = i; j < (i + count); j++)
 804                         if (irq_map[j].host != NULL) {
 805                                 i = j + 1;
 806                                 continue;
 807                         }
 808                 found = i;
 809                 break;
 810         }
 811         if (found == NO_IRQ) {
 812                 spin_unlock_irqrestore(&irq_big_lock, flags);
 813                 return NO_IRQ;
 814         }
 815  hint_found:
 816         for (i = found; i < (found + count); i++) {
 817                 irq_map[i].hwirq = host->inval_irq;
 818                 smp_wmb();
 819                 irq_map[i].host = host;
 820         }
 821         spin_unlock_irqrestore(&irq_big_lock, flags);
 822         return found;
 823 }
 824
 825 void irq_free_virt(unsigned int virq, unsigned int count)
 826 {
 827         unsigned long flags;
 828         unsigned int i;
 829
 830         WARN_ON (virq < NUM_ISA_INTERRUPTS);
 831         WARN_ON (count == 0 || (virq + count) > irq_virq_count);
 832
 833         spin_lock_irqsave(&irq_big_lock, flags);
 834         for (i = virq; i < (virq + count); i++) {
 835                 struct irq_host *host;
 836
 837                 if (i < NUM_ISA_INTERRUPTS ||
 838                     (virq + count) > irq_virq_count)
 839                         continue;
 840
 841                 host = irq_map[i].host;
 842                 irq_map[i].hwirq = host->inval_irq;
 843                 smp_wmb();
 844                 irq_map[i].host = NULL;
 845         }
 846         spin_unlock_irqrestore(&irq_big_lock, flags);
 847 }
 848
 849 void irq_early_init(void)
 850 {
 851         unsigned int i;
 852
 853         for (i = 0; i < NR_IRQS; i++)
 854                 get_irq_desc(i)->status |= IRQ_NOREQUEST;
 855 }
 856
 857 /* We need to create the radix trees late */
 858 static int irq_late_init(void)
 859 {
 860         struct irq_host *h;
 861         unsigned long flags;
 862
 863         irq_radix_wrlock(&flags);
 864         list_for_each_entry(h, &irq_hosts, link) {
 865                 if (h->revmap_type == IRQ_HOST_MAP_TREE)
 866                         INIT_RADIX_TREE(&h->revmap_data.tree, GFP_ATOMIC);
 867         }
 868         irq_radix_wrunlock(flags);
 869
 870         return 0;
 871 }
 872 arch_initcall(irq_late_init);
 873
 874 #endif /* CONFIG_PPC_MERGE */
 875
 876 #ifdef CONFIG_PCI_MSI
 877 int pci_enable_msi(struct pci_dev * pdev)
 878 {
 879         if (ppc_md.enable_msi)
 880                 return ppc_md.enable_msi(pdev);
 881         else
 882                 return -1;
 883 }
 884
 885 void pci_disable_msi(struct pci_dev * pdev)
 886 {
 887         if (ppc_md.disable_msi)
 888                 ppc_md.disable_msi(pdev);
 889 }
 890
 891 void pci_scan_msi_device(struct pci_dev *dev) {}
 892 int pci_enable_msix(struct pci_dev* dev, struct msix_entry *entries, int nvec) {return -1;}
 893 void pci_disable_msix(struct pci_dev *dev) {}
 894 void msi_remove_pci_irq_vectors(struct pci_dev *dev) {}
 895 void disable_msi_mode(struct pci_dev *dev, int pos, int type) {}
 896 void pci_no_msi(void) {}
 897
 898 #endif
 899
 900 #ifdef CONFIG_PPC64
 901 static int __init setup_noirqdistrib(char *str)
 902 {
 903         distribute_irqs = 0;
 904         return 1;
 905 }
 906
 907 __setup("noirqdistrib", setup_noirqdistrib);
 908 #endif /* CONFIG_PPC64 */