git.oblomov.eu Git - linux-2.6/blob - 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         struct pt_regs *old_regs = set_irq_regs(regs);
 191         unsigned int irq;
 192 #ifdef CONFIG_IRQSTACKS
 193         struct thread_info *curtp, *irqtp;
 194 #endif
 195
 196         irq_enter();
 197
 198 #ifdef CONFIG_DEBUG_STACKOVERFLOW
 199         /* Debugging check for stack overflow: is there less than 2KB free? */
 200         {
 201                 long sp;
 202
 203                 sp = __get_SP() & (THREAD_SIZE-1);
 204
 205                 if (unlikely(sp < (sizeof(struct thread_info) + 2048))) {
 206                         printk("do_IRQ: stack overflow: %ld\n",
 207                                 sp - sizeof(struct thread_info));
 208                         dump_stack();
 209                 }
 210         }
 211 #endif
 212
 213         /*
 214          * Every platform is required to implement ppc_md.get_irq.
 215          * This function will either return an irq number or -1 to
 216          * indicate there are no more pending.
 217          * The value -2 is for buggy hardware and means that this IRQ
 218          * has already been handled. -- Tom
 219          */
 220         irq = ppc_md.get_irq(regs);
 221
 222         if (irq != NO_IRQ && irq != NO_IRQ_IGNORE) {
 223 #ifdef CONFIG_IRQSTACKS
 224                 /* Switch to the irq stack to handle this */
 225                 curtp = current_thread_info();
 226                 irqtp = hardirq_ctx[smp_processor_id()];
 227                 if (curtp != irqtp) {
 228                         struct irq_desc *desc = irq_desc + irq;
 229                         void *handler = desc->handle_irq;
 230                         if (handler == NULL)
 231                                 handler = &__do_IRQ;
 232                         irqtp->task = curtp->task;
 233                         irqtp->flags = 0;
 234                         call_handle_irq(irq, desc, irqtp, handler);
 235                         irqtp->task = NULL;
 236                         if (irqtp->flags)
 237                                 set_bits(irqtp->flags, &curtp->flags);
 238                 } else
 239 #endif
 240                         generic_handle_irq(irq);
 241         } else if (irq != NO_IRQ_IGNORE)
 242                 /* That's not SMP safe ... but who cares ? */
 243                 ppc_spurious_interrupts++;
 244
 245         irq_exit();
 246         set_irq_regs(old_regs);
 247
 248 #ifdef CONFIG_PPC_ISERIES
 249         if (get_lppaca()->int_dword.fields.decr_int) {
 250                 get_lppaca()->int_dword.fields.decr_int = 0;
 251                 /* Signal a fake decrementer interrupt */
 252                 timer_interrupt(regs);
 253         }
 254 #endif
 255 }
 256
 257 void __init init_IRQ(void)
 258 {
 259         ppc_md.init_IRQ();
 260 #ifdef CONFIG_PPC64
 261         irq_ctx_init();
 262 #endif
 263 }
 264
 265
 266 #ifdef CONFIG_IRQSTACKS
 267 struct thread_info *softirq_ctx[NR_CPUS] __read_mostly;
 268 struct thread_info *hardirq_ctx[NR_CPUS] __read_mostly;
 269
 270 void irq_ctx_init(void)
 271 {
 272         struct thread_info *tp;
 273         int i;
 274
 275         for_each_possible_cpu(i) {
 276                 memset((void *)softirq_ctx[i], 0, THREAD_SIZE);
 277                 tp = softirq_ctx[i];
 278                 tp->cpu = i;
 279                 tp->preempt_count = SOFTIRQ_OFFSET;
 280
 281                 memset((void *)hardirq_ctx[i], 0, THREAD_SIZE);
 282                 tp = hardirq_ctx[i];
 283                 tp->cpu = i;
 284                 tp->preempt_count = HARDIRQ_OFFSET;
 285         }
 286 }
 287
 288 static inline void do_softirq_onstack(void)
 289 {
 290         struct thread_info *curtp, *irqtp;
 291
 292         curtp = current_thread_info();
 293         irqtp = softirq_ctx[smp_processor_id()];
 294         irqtp->task = curtp->task;
 295         call_do_softirq(irqtp);
 296         irqtp->task = NULL;
 297 }
 298
 299 #else
 300 #define do_softirq_onstack()    __do_softirq()
 301 #endif /* CONFIG_IRQSTACKS */
 302
 303 void do_softirq(void)
 304 {
 305         unsigned long flags;
 306
 307         if (in_interrupt())
 308                 return;
 309
 310         local_irq_save(flags);
 311
 312         if (local_softirq_pending())
 313                 do_softirq_onstack();
 314
 315         local_irq_restore(flags);
 316 }
 317 EXPORT_SYMBOL(do_softirq);
 318
 319
 320 /*
 321  * IRQ controller and virtual interrupts
 322  */
 323
 324 #ifdef CONFIG_PPC_MERGE
 325
 326 static LIST_HEAD(irq_hosts);
 327 static spinlock_t irq_big_lock = SPIN_LOCK_UNLOCKED;
 328 static DEFINE_PER_CPU(unsigned int, irq_radix_reader);
 329 static unsigned int irq_radix_writer;
 330 struct irq_map_entry irq_map[NR_IRQS];
 331 static unsigned int irq_virq_count = NR_IRQS;
 332 static struct irq_host *irq_default_host;
 333
 334 struct irq_host *irq_alloc_host(unsigned int revmap_type,
 335                                 unsigned int revmap_arg,
 336                                 struct irq_host_ops *ops,
 337                                 irq_hw_number_t inval_irq)
 338 {
 339         struct irq_host *host;
 340         unsigned int size = sizeof(struct irq_host);
 341         unsigned int i;
 342         unsigned int *rmap;
 343         unsigned long flags;
 344
 345         /* Allocate structure and revmap table if using linear mapping */
 346         if (revmap_type == IRQ_HOST_MAP_LINEAR)
 347                 size += revmap_arg * sizeof(unsigned int);
 348         if (mem_init_done)
 349                 host = kzalloc(size, GFP_KERNEL);
 350         else {
 351                 host = alloc_bootmem(size);
 352                 if (host)
 353                         memset(host, 0, size);
 354         }
 355         if (host == NULL)
 356                 return NULL;
 357
 358         /* Fill structure */
 359         host->revmap_type = revmap_type;
 360         host->inval_irq = inval_irq;
 361         host->ops = ops;
 362
 363         spin_lock_irqsave(&irq_big_lock, flags);
 364
 365         /* If it's a legacy controller, check for duplicates and
 366          * mark it as allocated (we use irq 0 host pointer for that
 367          */
 368         if (revmap_type == IRQ_HOST_MAP_LEGACY) {
 369                 if (irq_map[0].host != NULL) {
 370                         spin_unlock_irqrestore(&irq_big_lock, flags);
 371                         /* If we are early boot, we can't free the structure,
 372                          * too bad...
 373                          * this will be fixed once slab is made available early
 374                          * instead of the current cruft
 375                          */
 376                         if (mem_init_done)
 377                                 kfree(host);
 378                         return NULL;
 379                 }
 380                 irq_map[0].host = host;
 381         }
 382
 383         list_add(&host->link, &irq_hosts);
 384         spin_unlock_irqrestore(&irq_big_lock, flags);
 385
 386         /* Additional setups per revmap type */
 387         switch(revmap_type) {
 388         case IRQ_HOST_MAP_LEGACY:
 389                 /* 0 is always the invalid number for legacy */
 390                 host->inval_irq = 0;
 391                 /* setup us as the host for all legacy interrupts */
 392                 for (i = 1; i < NUM_ISA_INTERRUPTS; i++) {
 393                         irq_map[i].hwirq = 0;
 394                         smp_wmb();
 395                         irq_map[i].host = host;
 396                         smp_wmb();
 397
 398                         /* Clear norequest flags */
 399                         get_irq_desc(i)->status &= ~IRQ_NOREQUEST;
 400
 401                         /* Legacy flags are left to default at this point,
 402                          * one can then use irq_create_mapping() to
 403                          * explicitely change them
 404                          */
 405                         ops->map(host, i, i);
 406                 }
 407                 break;
 408         case IRQ_HOST_MAP_LINEAR:
 409                 rmap = (unsigned int *)(host + 1);
 410                 for (i = 0; i < revmap_arg; i++)
 411                         rmap[i] = IRQ_NONE;
 412                 host->revmap_data.linear.size = revmap_arg;
 413                 smp_wmb();
 414                 host->revmap_data.linear.revmap = rmap;
 415                 break;
 416         default:
 417                 break;
 418         }
 419
 420         pr_debug("irq: Allocated host of type %d @0x%p\n", revmap_type, host);
 421
 422         return host;
 423 }
 424
 425 struct irq_host *irq_find_host(struct device_node *node)
 426 {
 427         struct irq_host *h, *found = NULL;
 428         unsigned long flags;
 429
 430         /* We might want to match the legacy controller last since
 431          * it might potentially be set to match all interrupts in
 432          * the absence of a device node. This isn't a problem so far
 433          * yet though...
 434          */
 435         spin_lock_irqsave(&irq_big_lock, flags);
 436         list_for_each_entry(h, &irq_hosts, link)
 437                 if (h->ops->match == NULL || h->ops->match(h, node)) {
 438                         found = h;
 439                         break;
 440                 }
 441         spin_unlock_irqrestore(&irq_big_lock, flags);
 442         return found;
 443 }
 444 EXPORT_SYMBOL_GPL(irq_find_host);
 445
 446 void irq_set_default_host(struct irq_host *host)
 447 {
 448         pr_debug("irq: Default host set to @0x%p\n", host);
 449
 450         irq_default_host = host;
 451 }
 452
 453 void irq_set_virq_count(unsigned int count)
 454 {
 455         pr_debug("irq: Trying to set virq count to %d\n", count);
 456
 457         BUG_ON(count < NUM_ISA_INTERRUPTS);
 458         if (count < NR_IRQS)
 459                 irq_virq_count = count;
 460 }
 461
 462 /* radix tree not lockless safe ! we use a brlock-type mecanism
 463  * for now, until we can use a lockless radix tree
 464  */
 465 static void irq_radix_wrlock(unsigned long *flags)
 466 {
 467         unsigned int cpu, ok;
 468
 469         spin_lock_irqsave(&irq_big_lock, *flags);
 470         irq_radix_writer = 1;
 471         smp_mb();
 472         do {
 473                 barrier();
 474                 ok = 1;
 475                 for_each_possible_cpu(cpu) {
 476                         if (per_cpu(irq_radix_reader, cpu)) {
 477                                 ok = 0;
 478                                 break;
 479                         }
 480                 }
 481                 if (!ok)
 482                         cpu_relax();
 483         } while(!ok);
 484 }
 485
 486 static void irq_radix_wrunlock(unsigned long flags)
 487 {
 488         smp_wmb();
 489         irq_radix_writer = 0;
 490         spin_unlock_irqrestore(&irq_big_lock, flags);
 491 }
 492
 493 static void irq_radix_rdlock(unsigned long *flags)
 494 {
 495         local_irq_save(*flags);
 496         __get_cpu_var(irq_radix_reader) = 1;
 497         smp_mb();
 498         if (likely(irq_radix_writer == 0))
 499                 return;
 500         __get_cpu_var(irq_radix_reader) = 0;
 501         smp_wmb();
 502         spin_lock(&irq_big_lock);
 503         __get_cpu_var(irq_radix_reader) = 1;
 504         spin_unlock(&irq_big_lock);
 505 }
 506
 507 static void irq_radix_rdunlock(unsigned long flags)
 508 {
 509         __get_cpu_var(irq_radix_reader) = 0;
 510         local_irq_restore(flags);
 511 }
 512
 513
 514 unsigned int irq_create_mapping(struct irq_host *host,
 515                                 irq_hw_number_t hwirq)
 516 {
 517         unsigned int virq, hint;
 518
 519         pr_debug("irq: irq_create_mapping(0x%p, 0x%lx)\n", host, hwirq);
 520
 521         /* Look for default host if nececssary */
 522         if (host == NULL)
 523                 host = irq_default_host;
 524         if (host == NULL) {
 525                 printk(KERN_WARNING "irq_create_mapping called for"
 526                        " NULL host, hwirq=%lx\n", hwirq);
 527                 WARN_ON(1);
 528                 return NO_IRQ;
 529         }
 530         pr_debug("irq: -> using host @%p\n", host);
 531
 532         /* Check if mapping already exist, if it does, call
 533          * host->ops->map() to update the flags
 534          */
 535         virq = irq_find_mapping(host, hwirq);
 536         if (virq != IRQ_NONE) {
 537                 pr_debug("irq: -> existing mapping on virq %d\n", virq);
 538                 return virq;
 539         }
 540
 541         /* Get a virtual interrupt number */
 542         if (host->revmap_type == IRQ_HOST_MAP_LEGACY) {
 543                 /* Handle legacy */
 544                 virq = (unsigned int)hwirq;
 545                 if (virq == 0 || virq >= NUM_ISA_INTERRUPTS)
 546                         return NO_IRQ;
 547                 return virq;
 548         } else {
 549                 /* Allocate a virtual interrupt number */
 550                 hint = hwirq % irq_virq_count;
 551                 virq = irq_alloc_virt(host, 1, hint);
 552                 if (virq == NO_IRQ) {
 553                         pr_debug("irq: -> virq allocation failed\n");
 554                         return NO_IRQ;
 555                 }
 556         }
 557         pr_debug("irq: -> obtained virq %d\n", virq);
 558
 559         /* Clear IRQ_NOREQUEST flag */
 560         get_irq_desc(virq)->status &= ~IRQ_NOREQUEST;
 561
 562         /* map it */
 563         smp_wmb();
 564         irq_map[virq].hwirq = hwirq;
 565         smp_mb();
 566         if (host->ops->map(host, virq, hwirq)) {
 567                 pr_debug("irq: -> mapping failed, freeing\n");
 568                 irq_free_virt(virq, 1);
 569                 return NO_IRQ;
 570         }
 571         return virq;
 572 }
 573 EXPORT_SYMBOL_GPL(irq_create_mapping);
 574
 575 extern unsigned int irq_create_of_mapping(struct device_node *controller,
 576                                           u32 *intspec, unsigned int intsize)
 577 {
 578         struct irq_host *host;
 579         irq_hw_number_t hwirq;
 580         unsigned int type = IRQ_TYPE_NONE;
 581         unsigned int virq;
 582
 583         if (controller == NULL)
 584                 host = irq_default_host;
 585         else
 586                 host = irq_find_host(controller);
 587         if (host == NULL) {
 588                 printk(KERN_WARNING "irq: no irq host found for %s !\n",
 589                        controller->full_name);
 590                 return NO_IRQ;
 591         }
 592
 593         /* If host has no translation, then we assume interrupt line */
 594         if (host->ops->xlate == NULL)
 595                 hwirq = intspec[0];
 596         else {
 597                 if (host->ops->xlate(host, controller, intspec, intsize,
 598                                      &hwirq, &type))
 599                         return NO_IRQ;
 600         }
 601
 602         /* Create mapping */
 603         virq = irq_create_mapping(host, hwirq);
 604         if (virq == NO_IRQ)
 605                 return virq;
 606
 607         /* Set type if specified and different than the current one */
 608         if (type != IRQ_TYPE_NONE &&
 609             type != (get_irq_desc(virq)->status & IRQF_TRIGGER_MASK))
 610                 set_irq_type(virq, type);
 611         return virq;
 612 }
 613 EXPORT_SYMBOL_GPL(irq_create_of_mapping);
 614
 615 unsigned int irq_of_parse_and_map(struct device_node *dev, int index)
 616 {
 617         struct of_irq oirq;
 618
 619         if (of_irq_map_one(dev, index, &oirq))
 620                 return NO_IRQ;
 621
 622         return irq_create_of_mapping(oirq.controller, oirq.specifier,
 623                                      oirq.size);
 624 }
 625 EXPORT_SYMBOL_GPL(irq_of_parse_and_map);
 626
 627 void irq_dispose_mapping(unsigned int virq)
 628 {
 629         struct irq_host *host = irq_map[virq].host;
 630         irq_hw_number_t hwirq;
 631         unsigned long flags;
 632
 633         WARN_ON (host == NULL);
 634         if (host == NULL)
 635                 return;
 636
 637         /* Never unmap legacy interrupts */
 638         if (host->revmap_type == IRQ_HOST_MAP_LEGACY)
 639                 return;
 640
 641         /* remove chip and handler */
 642         set_irq_chip_and_handler(virq, NULL, NULL);
 643
 644         /* Make sure it's completed */
 645         synchronize_irq(virq);
 646
 647         /* Tell the PIC about it */
 648         if (host->ops->unmap)
 649                 host->ops->unmap(host, virq);
 650         smp_mb();
 651
 652         /* Clear reverse map */
 653         hwirq = irq_map[virq].hwirq;
 654         switch(host->revmap_type) {
 655         case IRQ_HOST_MAP_LINEAR:
 656                 if (hwirq < host->revmap_data.linear.size)
 657                         host->revmap_data.linear.revmap[hwirq] = IRQ_NONE;
 658                 break;
 659         case IRQ_HOST_MAP_TREE:
 660                 /* Check if radix tree allocated yet */
 661                 if (host->revmap_data.tree.gfp_mask == 0)
 662                         break;
 663                 irq_radix_wrlock(&flags);
 664                 radix_tree_delete(&host->revmap_data.tree, hwirq);
 665                 irq_radix_wrunlock(flags);
 666                 break;
 667         }
 668
 669         /* Destroy map */
 670         smp_mb();
 671         irq_map[virq].hwirq = host->inval_irq;
 672
 673         /* Set some flags */
 674         get_irq_desc(virq)->status |= IRQ_NOREQUEST;
 675
 676         /* Free it */
 677         irq_free_virt(virq, 1);
 678 }
 679 EXPORT_SYMBOL_GPL(irq_dispose_mapping);
 680
 681 unsigned int irq_find_mapping(struct irq_host *host,
 682                               irq_hw_number_t hwirq)
 683 {
 684         unsigned int i;
 685         unsigned int hint = hwirq % irq_virq_count;
 686
 687         /* Look for default host if nececssary */
 688         if (host == NULL)
 689                 host = irq_default_host;
 690         if (host == NULL)
 691                 return NO_IRQ;
 692
 693         /* legacy -> bail early */
 694         if (host->revmap_type == IRQ_HOST_MAP_LEGACY)
 695                 return hwirq;
 696
 697         /* Slow path does a linear search of the map */
 698         if (hint < NUM_ISA_INTERRUPTS)
 699                 hint = NUM_ISA_INTERRUPTS;
 700         i = hint;
 701         do  {
 702                 if (irq_map[i].host == host &&
 703                     irq_map[i].hwirq == hwirq)
 704                         return i;
 705                 i++;
 706                 if (i >= irq_virq_count)
 707                         i = NUM_ISA_INTERRUPTS;
 708         } while(i != hint);
 709         return NO_IRQ;
 710 }
 711 EXPORT_SYMBOL_GPL(irq_find_mapping);
 712
 713
 714 unsigned int irq_radix_revmap(struct irq_host *host,
 715                               irq_hw_number_t hwirq)
 716 {
 717         struct radix_tree_root *tree;
 718         struct irq_map_entry *ptr;
 719         unsigned int virq;
 720         unsigned long flags;
 721
 722         WARN_ON(host->revmap_type != IRQ_HOST_MAP_TREE);
 723
 724         /* Check if the radix tree exist yet. We test the value of
 725          * the gfp_mask for that. Sneaky but saves another int in the
 726          * structure. If not, we fallback to slow mode
 727          */
 728         tree = &host->revmap_data.tree;
 729         if (tree->gfp_mask == 0)
 730                 return irq_find_mapping(host, hwirq);
 731
 732         /* Now try to resolve */
 733         irq_radix_rdlock(&flags);
 734         ptr = radix_tree_lookup(tree, hwirq);
 735         irq_radix_rdunlock(flags);
 736
 737         /* Found it, return */
 738         if (ptr) {
 739                 virq = ptr - irq_map;
 740                 return virq;
 741         }
 742
 743         /* If not there, try to insert it */
 744         virq = irq_find_mapping(host, hwirq);
 745         if (virq != NO_IRQ) {
 746                 irq_radix_wrlock(&flags);
 747                 radix_tree_insert(tree, hwirq, &irq_map[virq]);
 748                 irq_radix_wrunlock(flags);
 749         }
 750         return virq;
 751 }
 752
 753 unsigned int irq_linear_revmap(struct irq_host *host,
 754                                irq_hw_number_t hwirq)
 755 {
 756         unsigned int *revmap;
 757
 758         WARN_ON(host->revmap_type != IRQ_HOST_MAP_LINEAR);
 759
 760         /* Check revmap bounds */
 761         if (unlikely(hwirq >= host->revmap_data.linear.size))
 762                 return irq_find_mapping(host, hwirq);
 763
 764         /* Check if revmap was allocated */
 765         revmap = host->revmap_data.linear.revmap;
 766         if (unlikely(revmap == NULL))
 767                 return irq_find_mapping(host, hwirq);
 768
 769         /* Fill up revmap with slow path if no mapping found */
 770         if (unlikely(revmap[hwirq] == NO_IRQ))
 771                 revmap[hwirq] = irq_find_mapping(host, hwirq);
 772
 773         return revmap[hwirq];
 774 }
 775
 776 unsigned int irq_alloc_virt(struct irq_host *host,
 777                             unsigned int count,
 778                             unsigned int hint)
 779 {
 780         unsigned long flags;
 781         unsigned int i, j, found = NO_IRQ;
 782
 783         if (count == 0 || count > (irq_virq_count - NUM_ISA_INTERRUPTS))
 784                 return NO_IRQ;
 785
 786         spin_lock_irqsave(&irq_big_lock, flags);
 787
 788         /* Use hint for 1 interrupt if any */
 789         if (count == 1 && hint >= NUM_ISA_INTERRUPTS &&
 790             hint < irq_virq_count && irq_map[hint].host == NULL) {
 791                 found = hint;
 792                 goto hint_found;
 793         }
 794
 795         /* Look for count consecutive numbers in the allocatable
 796          * (non-legacy) space
 797          */
 798         for (i = NUM_ISA_INTERRUPTS, j = 0; i < irq_virq_count; i++) {
 799                 if (irq_map[i].host != NULL)
 800                         j = 0;
 801                 else
 802                         j++;
 803
 804                 if (j == count) {
 805                         found = i - count + 1;
 806                         break;
 807                 }
 808         }
 809         if (found == NO_IRQ) {
 810                 spin_unlock_irqrestore(&irq_big_lock, flags);
 811                 return NO_IRQ;
 812         }
 813  hint_found:
 814         for (i = found; i < (found + count); i++) {
 815                 irq_map[i].hwirq = host->inval_irq;
 816                 smp_wmb();
 817                 irq_map[i].host = host;
 818         }
 819         spin_unlock_irqrestore(&irq_big_lock, flags);
 820         return found;
 821 }
 822
 823 void irq_free_virt(unsigned int virq, unsigned int count)
 824 {
 825         unsigned long flags;
 826         unsigned int i;
 827
 828         WARN_ON (virq < NUM_ISA_INTERRUPTS);
 829         WARN_ON (count == 0 || (virq + count) > irq_virq_count);
 830
 831         spin_lock_irqsave(&irq_big_lock, flags);
 832         for (i = virq; i < (virq + count); i++) {
 833                 struct irq_host *host;
 834
 835                 if (i < NUM_ISA_INTERRUPTS ||
 836                     (virq + count) > irq_virq_count)
 837                         continue;
 838
 839                 host = irq_map[i].host;
 840                 irq_map[i].hwirq = host->inval_irq;
 841                 smp_wmb();
 842                 irq_map[i].host = NULL;
 843         }
 844         spin_unlock_irqrestore(&irq_big_lock, flags);
 845 }
 846
 847 void irq_early_init(void)
 848 {
 849         unsigned int i;
 850
 851         for (i = 0; i < NR_IRQS; i++)
 852                 get_irq_desc(i)->status |= IRQ_NOREQUEST;
 853 }
 854
 855 /* We need to create the radix trees late */
 856 static int irq_late_init(void)
 857 {
 858         struct irq_host *h;
 859         unsigned long flags;
 860
 861         irq_radix_wrlock(&flags);
 862         list_for_each_entry(h, &irq_hosts, link) {
 863                 if (h->revmap_type == IRQ_HOST_MAP_TREE)
 864                         INIT_RADIX_TREE(&h->revmap_data.tree, GFP_ATOMIC);
 865         }
 866         irq_radix_wrunlock(flags);
 867
 868         return 0;
 869 }
 870 arch_initcall(irq_late_init);
 871
 872 #endif /* CONFIG_PPC_MERGE */
 873
 874 #ifdef CONFIG_PCI_MSI
 875 int pci_enable_msi(struct pci_dev * pdev)
 876 {
 877         if (ppc_md.enable_msi)
 878                 return ppc_md.enable_msi(pdev);
 879         else
 880                 return -1;
 881 }
 882 EXPORT_SYMBOL(pci_enable_msi);
 883
 884 void pci_disable_msi(struct pci_dev * pdev)
 885 {
 886         if (ppc_md.disable_msi)
 887                 ppc_md.disable_msi(pdev);
 888 }
 889 EXPORT_SYMBOL(pci_disable_msi);
 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 EXPORT_SYMBOL(pci_enable_msix);
 898 EXPORT_SYMBOL(pci_disable_msix);
 899
 900 #endif
 901
 902 #ifdef CONFIG_PPC64
 903 static int __init setup_noirqdistrib(char *str)
 904 {
 905         distribute_irqs = 0;
 906         return 1;
 907 }
 908
 909 __setup("noirqdistrib", setup_noirqdistrib);
 910 #endif /* CONFIG_PPC64 */