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  *
  11  * This program is free software; you can redistribute it and/or
  12  * modify it under the terms of the GNU General Public License
  13  * as published by the Free Software Foundation; either version
  14  * 2 of the License, or (at your option) any later version.
  15  *
  16  * This file contains the code used by various IRQ handling routines:
  17  * asking for different IRQ's should be done through these routines
  18  * instead of just grabbing them. Thus setups with different IRQ numbers
  19  * shouldn't result in any weird surprises, and installing new handlers
  20  * should be easier.
  21  *
  22  * The MPC8xx has an interrupt mask in the SIU.  If a bit is set, the
  23  * interrupt is _enabled_.  As expected, IRQ0 is bit 0 in the 32-bit
  24  * mask register (of which only 16 are defined), hence the weird shifting
  25  * and complement of the cached_irq_mask.  I want to be able to stuff
  26  * this right into the SIU SMASK register.
  27  * Many of the prep/chrp functions are conditional compiled on CONFIG_8xx
  28  * to reduce code space and undefined function references.
  29  */
  30
  31 #undef DEBUG
  32
  33 #include <linux/module.h>
  34 #include <linux/threads.h>
  35 #include <linux/kernel_stat.h>
  36 #include <linux/signal.h>
  37 #include <linux/sched.h>
  38 #include <linux/ptrace.h>
  39 #include <linux/ioport.h>
  40 #include <linux/interrupt.h>
  41 #include <linux/timex.h>
  42 #include <linux/init.h>
  43 #include <linux/slab.h>
  44 #include <linux/delay.h>
  45 #include <linux/irq.h>
  46 #include <linux/seq_file.h>
  47 #include <linux/cpumask.h>
  48 #include <linux/profile.h>
  49 #include <linux/bitops.h>
  50 #include <linux/list.h>
  51 #include <linux/radix-tree.h>
  52 #include <linux/mutex.h>
  53 #include <linux/bootmem.h>
  54 #include <linux/pci.h>
  55
  56 #include <asm/uaccess.h>
  57 #include <asm/system.h>
  58 #include <asm/io.h>
  59 #include <asm/pgtable.h>
  60 #include <asm/irq.h>
  61 #include <asm/cache.h>
  62 #include <asm/prom.h>
  63 #include <asm/ptrace.h>
  64 #include <asm/machdep.h>
  65 #include <asm/udbg.h>
  66 #ifdef CONFIG_PPC64
  67 #include <asm/paca.h>
  68 #include <asm/firmware.h>
  69 #include <asm/lv1call.h>
  70 #endif
  71
  72 int __irq_offset_value;
  73 static int ppc_spurious_interrupts;
  74
  75 #ifdef CONFIG_PPC32
  76 EXPORT_SYMBOL(__irq_offset_value);
  77 atomic_t ppc_n_lost_interrupts;
  78
  79 #ifndef CONFIG_PPC_MERGE
  80 #define NR_MASK_WORDS   ((NR_IRQS + 31) / 32)
  81 unsigned long ppc_cached_irq_mask[NR_MASK_WORDS];
  82 #endif
  83
  84 #ifdef CONFIG_TAU_INT
  85 extern int tau_initialized;
  86 extern int tau_interrupts(int);
  87 #endif
  88 #endif /* CONFIG_PPC32 */
  89
  90 #if defined(CONFIG_SMP) && !defined(CONFIG_PPC_MERGE)
  91 extern atomic_t ipi_recv;
  92 extern atomic_t ipi_sent;
  93 #endif
  94
  95 #ifdef CONFIG_PPC64
  96 EXPORT_SYMBOL(irq_desc);
  97
  98 int distribute_irqs = 1;
  99
 100 static inline unsigned long get_hard_enabled(void)
 101 {
 102         unsigned long enabled;
 103
 104         __asm__ __volatile__("lbz %0,%1(13)"
 105         : "=r" (enabled) : "i" (offsetof(struct paca_struct, hard_enabled)));
 106
 107         return enabled;
 108 }
 109
 110 static inline void set_soft_enabled(unsigned long enable)
 111 {
 112         __asm__ __volatile__("stb %0,%1(13)"
 113         : : "r" (enable), "i" (offsetof(struct paca_struct, soft_enabled)));
 114 }
 115
 116 void local_irq_restore(unsigned long en)
 117 {
 118         /*
 119          * get_paca()->soft_enabled = en;
 120          * Is it ever valid to use local_irq_restore(0) when soft_enabled is 1?
 121          * That was allowed before, and in such a case we do need to take care
 122          * that gcc will set soft_enabled directly via r13, not choose to use
 123          * an intermediate register, lest we're preempted to a different cpu.
 124          */
 125         set_soft_enabled(en);
 126         if (!en)
 127                 return;
 128
 129         if (firmware_has_feature(FW_FEATURE_ISERIES)) {
 130                 /*
 131                  * Do we need to disable preemption here?  Not really: in the
 132                  * unlikely event that we're preempted to a different cpu in
 133                  * between getting r13, loading its lppaca_ptr, and loading
 134                  * its any_int, we might call iseries_handle_interrupts without
 135                  * an interrupt pending on the new cpu, but that's no disaster,
 136                  * is it?  And the business of preempting us off the old cpu
 137                  * would itself involve a local_irq_restore which handles the
 138                  * interrupt to that cpu.
 139                  *
 140                  * But use "local_paca->lppaca_ptr" instead of "get_lppaca()"
 141                  * to avoid any preemption checking added into get_paca().
 142                  */
 143                 if (local_paca->lppaca_ptr->int_dword.any_int)
 144                         iseries_handle_interrupts();
 145                 return;
 146         }
 147
 148         /*
 149          * if (get_paca()->hard_enabled) return;
 150          * But again we need to take care that gcc gets hard_enabled directly
 151          * via r13, not choose to use an intermediate register, lest we're
 152          * preempted to a different cpu in between the two instructions.
 153          */
 154         if (get_hard_enabled())
 155                 return;
 156
 157         /*
 158          * Need to hard-enable interrupts here.  Since currently disabled,
 159          * no need to take further asm precautions against preemption; but
 160          * use local_paca instead of get_paca() to avoid preemption checking.
 161          */
 162         local_paca->hard_enabled = en;
 163         if ((int)mfspr(SPRN_DEC) < 0)
 164                 mtspr(SPRN_DEC, 1);
 165
 166         /*
 167          * Force the delivery of pending soft-disabled interrupts on PS3.
 168          * Any HV call will have this side effect.
 169          */
 170         if (firmware_has_feature(FW_FEATURE_PS3_LV1)) {
 171                 u64 tmp;
 172                 lv1_get_version_info(&tmp);
 173         }
 174
 175         __hard_irq_enable();
 176 }
 177 #endif /* CONFIG_PPC64 */
 178
 179 int show_interrupts(struct seq_file *p, void *v)
 180 {
 181         int i = *(loff_t *)v, j;
 182         struct irqaction *action;
 183         irq_desc_t *desc;
 184         unsigned long flags;
 185
 186         if (i == 0) {
 187                 seq_puts(p, "           ");
 188                 for_each_online_cpu(j)
 189                         seq_printf(p, "CPU%d       ", j);
 190                 seq_putc(p, '\n');
 191         }
 192
 193         if (i < NR_IRQS) {
 194                 desc = get_irq_desc(i);
 195                 spin_lock_irqsave(&desc->lock, flags);
 196                 action = desc->action;
 197                 if (!action || !action->handler)
 198                         goto skip;
 199                 seq_printf(p, "%3d: ", i);
 200 #ifdef CONFIG_SMP
 201                 for_each_online_cpu(j)
 202                         seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
 203 #else
 204                 seq_printf(p, "%10u ", kstat_irqs(i));
 205 #endif /* CONFIG_SMP */
 206                 if (desc->chip)
 207                         seq_printf(p, " %s ", desc->chip->typename);
 208                 else
 209                         seq_puts(p, "  None      ");
 210                 seq_printf(p, "%s", (desc->status & IRQ_LEVEL) ? "Level " : "Edge  ");
 211                 seq_printf(p, "    %s", action->name);
 212                 for (action = action->next; action; action = action->next)
 213                         seq_printf(p, ", %s", action->name);
 214                 seq_putc(p, '\n');
 215 skip:
 216                 spin_unlock_irqrestore(&desc->lock, flags);
 217         } else if (i == NR_IRQS) {
 218 #ifdef CONFIG_PPC32
 219 #ifdef CONFIG_TAU_INT
 220                 if (tau_initialized){
 221                         seq_puts(p, "TAU: ");
 222                         for_each_online_cpu(j)
 223                                 seq_printf(p, "%10u ", tau_interrupts(j));
 224                         seq_puts(p, "  PowerPC             Thermal Assist (cpu temp)\n");
 225                 }
 226 #endif
 227 #if defined(CONFIG_SMP) && !defined(CONFIG_PPC_MERGE)
 228                 /* should this be per processor send/receive? */
 229                 seq_printf(p, "IPI (recv/sent): %10u/%u\n",
 230                                 atomic_read(&ipi_recv), atomic_read(&ipi_sent));
 231 #endif
 232 #endif /* CONFIG_PPC32 */
 233                 seq_printf(p, "BAD: %10u\n", ppc_spurious_interrupts);
 234         }
 235         return 0;
 236 }
 237
 238 #ifdef CONFIG_HOTPLUG_CPU
 239 void fixup_irqs(cpumask_t map)
 240 {
 241         unsigned int irq;
 242         static int warned;
 243
 244         for_each_irq(irq) {
 245                 cpumask_t mask;
 246
 247                 if (irq_desc[irq].status & IRQ_PER_CPU)
 248                         continue;
 249
 250                 cpus_and(mask, irq_desc[irq].affinity, map);
 251                 if (any_online_cpu(mask) == NR_CPUS) {
 252                         printk("Breaking affinity for irq %i\n", irq);
 253                         mask = map;
 254                 }
 255                 if (irq_desc[irq].chip->set_affinity)
 256                         irq_desc[irq].chip->set_affinity(irq, mask);
 257                 else if (irq_desc[irq].action && !(warned++))
 258                         printk("Cannot set affinity for irq %i\n", irq);
 259         }
 260
 261         local_irq_enable();
 262         mdelay(1);
 263         local_irq_disable();
 264 }
 265 #endif
 266
 267 void do_IRQ(struct pt_regs *regs)
 268 {
 269         struct pt_regs *old_regs = set_irq_regs(regs);
 270         unsigned int irq;
 271 #ifdef CONFIG_IRQSTACKS
 272         struct thread_info *curtp, *irqtp;
 273 #endif
 274
 275         irq_enter();
 276
 277 #ifdef CONFIG_DEBUG_STACKOVERFLOW
 278         /* Debugging check for stack overflow: is there less than 2KB free? */
 279         {
 280                 long sp;
 281
 282                 sp = __get_SP() & (THREAD_SIZE-1);
 283
 284                 if (unlikely(sp < (sizeof(struct thread_info) + 2048))) {
 285                         printk("do_IRQ: stack overflow: %ld\n",
 286                                 sp - sizeof(struct thread_info));
 287                         dump_stack();
 288                 }
 289         }
 290 #endif
 291
 292         /*
 293          * Every platform is required to implement ppc_md.get_irq.
 294          * This function will either return an irq number or NO_IRQ to
 295          * indicate there are no more pending.
 296          * The value NO_IRQ_IGNORE is for buggy hardware and means that this
 297          * IRQ has already been handled. -- Tom
 298          */
 299         irq = ppc_md.get_irq();
 300
 301         if (irq != NO_IRQ && irq != NO_IRQ_IGNORE) {
 302 #ifdef CONFIG_IRQSTACKS
 303                 /* Switch to the irq stack to handle this */
 304                 curtp = current_thread_info();
 305                 irqtp = hardirq_ctx[smp_processor_id()];
 306                 if (curtp != irqtp) {
 307                         struct irq_desc *desc = irq_desc + irq;
 308                         void *handler = desc->handle_irq;
 309                         if (handler == NULL)
 310                                 handler = &__do_IRQ;
 311                         irqtp->task = curtp->task;
 312                         irqtp->flags = 0;
 313                         call_handle_irq(irq, desc, irqtp, handler);
 314                         irqtp->task = NULL;
 315                         if (irqtp->flags)
 316                                 set_bits(irqtp->flags, &curtp->flags);
 317                 } else
 318 #endif
 319                         generic_handle_irq(irq);
 320         } else if (irq != NO_IRQ_IGNORE)
 321                 /* That's not SMP safe ... but who cares ? */
 322                 ppc_spurious_interrupts++;
 323
 324         irq_exit();
 325         set_irq_regs(old_regs);
 326
 327 #ifdef CONFIG_PPC_ISERIES
 328         if (firmware_has_feature(FW_FEATURE_ISERIES) &&
 329                         get_lppaca()->int_dword.fields.decr_int) {
 330                 get_lppaca()->int_dword.fields.decr_int = 0;
 331                 /* Signal a fake decrementer interrupt */
 332                 timer_interrupt(regs);
 333         }
 334 #endif
 335 }
 336
 337 void __init init_IRQ(void)
 338 {
 339         ppc_md.init_IRQ();
 340 #ifdef CONFIG_PPC64
 341         irq_ctx_init();
 342 #endif
 343 }
 344
 345
 346 #ifdef CONFIG_IRQSTACKS
 347 struct thread_info *softirq_ctx[NR_CPUS] __read_mostly;
 348 struct thread_info *hardirq_ctx[NR_CPUS] __read_mostly;
 349
 350 void irq_ctx_init(void)
 351 {
 352         struct thread_info *tp;
 353         int i;
 354
 355         for_each_possible_cpu(i) {
 356                 memset((void *)softirq_ctx[i], 0, THREAD_SIZE);
 357                 tp = softirq_ctx[i];
 358                 tp->cpu = i;
 359                 tp->preempt_count = SOFTIRQ_OFFSET;
 360
 361                 memset((void *)hardirq_ctx[i], 0, THREAD_SIZE);
 362                 tp = hardirq_ctx[i];
 363                 tp->cpu = i;
 364                 tp->preempt_count = HARDIRQ_OFFSET;
 365         }
 366 }
 367
 368 static inline void do_softirq_onstack(void)
 369 {
 370         struct thread_info *curtp, *irqtp;
 371
 372         curtp = current_thread_info();
 373         irqtp = softirq_ctx[smp_processor_id()];
 374         irqtp->task = curtp->task;
 375         call_do_softirq(irqtp);
 376         irqtp->task = NULL;
 377 }
 378
 379 #else
 380 #define do_softirq_onstack()    __do_softirq()
 381 #endif /* CONFIG_IRQSTACKS */
 382
 383 void do_softirq(void)
 384 {
 385         unsigned long flags;
 386
 387         if (in_interrupt())
 388                 return;
 389
 390         local_irq_save(flags);
 391
 392         if (local_softirq_pending())
 393                 do_softirq_onstack();
 394
 395         local_irq_restore(flags);
 396 }
 397 EXPORT_SYMBOL(do_softirq);
 398
 399
 400 /*
 401  * IRQ controller and virtual interrupts
 402  */
 403
 404 #ifdef CONFIG_PPC_MERGE
 405
 406 static LIST_HEAD(irq_hosts);
 407 static DEFINE_SPINLOCK(irq_big_lock);
 408 static DEFINE_PER_CPU(unsigned int, irq_radix_reader);
 409 static unsigned int irq_radix_writer;
 410 struct irq_map_entry irq_map[NR_IRQS];
 411 static unsigned int irq_virq_count = NR_IRQS;
 412 static struct irq_host *irq_default_host;
 413
 414 struct irq_host *irq_alloc_host(unsigned int revmap_type,
 415                                 unsigned int revmap_arg,
 416                                 struct irq_host_ops *ops,
 417                                 irq_hw_number_t inval_irq)
 418 {
 419         struct irq_host *host;
 420         unsigned int size = sizeof(struct irq_host);
 421         unsigned int i;
 422         unsigned int *rmap;
 423         unsigned long flags;
 424
 425         /* Allocate structure and revmap table if using linear mapping */
 426         if (revmap_type == IRQ_HOST_MAP_LINEAR)
 427                 size += revmap_arg * sizeof(unsigned int);
 428         if (mem_init_done)
 429                 host = kzalloc(size, GFP_KERNEL);
 430         else {
 431                 host = alloc_bootmem(size);
 432                 if (host)
 433                         memset(host, 0, size);
 434         }
 435         if (host == NULL)
 436                 return NULL;
 437
 438         /* Fill structure */
 439         host->revmap_type = revmap_type;
 440         host->inval_irq = inval_irq;
 441         host->ops = ops;
 442
 443         spin_lock_irqsave(&irq_big_lock, flags);
 444
 445         /* If it's a legacy controller, check for duplicates and
 446          * mark it as allocated (we use irq 0 host pointer for that
 447          */
 448         if (revmap_type == IRQ_HOST_MAP_LEGACY) {
 449                 if (irq_map[0].host != NULL) {
 450                         spin_unlock_irqrestore(&irq_big_lock, flags);
 451                         /* If we are early boot, we can't free the structure,
 452                          * too bad...
 453                          * this will be fixed once slab is made available early
 454                          * instead of the current cruft
 455                          */
 456                         if (mem_init_done)
 457                                 kfree(host);
 458                         return NULL;
 459                 }
 460                 irq_map[0].host = host;
 461         }
 462
 463         list_add(&host->link, &irq_hosts);
 464         spin_unlock_irqrestore(&irq_big_lock, flags);
 465
 466         /* Additional setups per revmap type */
 467         switch(revmap_type) {
 468         case IRQ_HOST_MAP_LEGACY:
 469                 /* 0 is always the invalid number for legacy */
 470                 host->inval_irq = 0;
 471                 /* setup us as the host for all legacy interrupts */
 472                 for (i = 1; i < NUM_ISA_INTERRUPTS; i++) {
 473                         irq_map[i].hwirq = 0;
 474                         smp_wmb();
 475                         irq_map[i].host = host;
 476                         smp_wmb();
 477
 478                         /* Clear norequest flags */
 479                         get_irq_desc(i)->status &= ~IRQ_NOREQUEST;
 480
 481                         /* Legacy flags are left to default at this point,
 482                          * one can then use irq_create_mapping() to
 483                          * explicitely change them
 484                          */
 485                         ops->map(host, i, i);
 486                 }
 487                 break;
 488         case IRQ_HOST_MAP_LINEAR:
 489                 rmap = (unsigned int *)(host + 1);
 490                 for (i = 0; i < revmap_arg; i++)
 491                         rmap[i] = NO_IRQ;
 492                 host->revmap_data.linear.size = revmap_arg;
 493                 smp_wmb();
 494                 host->revmap_data.linear.revmap = rmap;
 495                 break;
 496         default:
 497                 break;
 498         }
 499
 500         pr_debug("irq: Allocated host of type %d @0x%p\n", revmap_type, host);
 501
 502         return host;
 503 }
 504
 505 struct irq_host *irq_find_host(struct device_node *node)
 506 {
 507         struct irq_host *h, *found = NULL;
 508         unsigned long flags;
 509
 510         /* We might want to match the legacy controller last since
 511          * it might potentially be set to match all interrupts in
 512          * the absence of a device node. This isn't a problem so far
 513          * yet though...
 514          */
 515         spin_lock_irqsave(&irq_big_lock, flags);
 516         list_for_each_entry(h, &irq_hosts, link)
 517                 if (h->ops->match == NULL || h->ops->match(h, node)) {
 518                         found = h;
 519                         break;
 520                 }
 521         spin_unlock_irqrestore(&irq_big_lock, flags);
 522         return found;
 523 }
 524 EXPORT_SYMBOL_GPL(irq_find_host);
 525
 526 void irq_set_default_host(struct irq_host *host)
 527 {
 528         pr_debug("irq: Default host set to @0x%p\n", host);
 529
 530         irq_default_host = host;
 531 }
 532
 533 void irq_set_virq_count(unsigned int count)
 534 {
 535         pr_debug("irq: Trying to set virq count to %d\n", count);
 536
 537         BUG_ON(count < NUM_ISA_INTERRUPTS);
 538         if (count < NR_IRQS)
 539                 irq_virq_count = count;
 540 }
 541
 542 /* radix tree not lockless safe ! we use a brlock-type mecanism
 543  * for now, until we can use a lockless radix tree
 544  */
 545 static void irq_radix_wrlock(unsigned long *flags)
 546 {
 547         unsigned int cpu, ok;
 548
 549         spin_lock_irqsave(&irq_big_lock, *flags);
 550         irq_radix_writer = 1;
 551         smp_mb();
 552         do {
 553                 barrier();
 554                 ok = 1;
 555                 for_each_possible_cpu(cpu) {
 556                         if (per_cpu(irq_radix_reader, cpu)) {
 557                                 ok = 0;
 558                                 break;
 559                         }
 560                 }
 561                 if (!ok)
 562                         cpu_relax();
 563         } while(!ok);
 564 }
 565
 566 static void irq_radix_wrunlock(unsigned long flags)
 567 {
 568         smp_wmb();
 569         irq_radix_writer = 0;
 570         spin_unlock_irqrestore(&irq_big_lock, flags);
 571 }
 572
 573 static void irq_radix_rdlock(unsigned long *flags)
 574 {
 575         local_irq_save(*flags);
 576         __get_cpu_var(irq_radix_reader) = 1;
 577         smp_mb();
 578         if (likely(irq_radix_writer == 0))
 579                 return;
 580         __get_cpu_var(irq_radix_reader) = 0;
 581         smp_wmb();
 582         spin_lock(&irq_big_lock);
 583         __get_cpu_var(irq_radix_reader) = 1;
 584         spin_unlock(&irq_big_lock);
 585 }
 586
 587 static void irq_radix_rdunlock(unsigned long flags)
 588 {
 589         __get_cpu_var(irq_radix_reader) = 0;
 590         local_irq_restore(flags);
 591 }
 592
 593
 594 unsigned int irq_create_mapping(struct irq_host *host,
 595                                 irq_hw_number_t hwirq)
 596 {
 597         unsigned int virq, hint;
 598
 599         pr_debug("irq: irq_create_mapping(0x%p, 0x%lx)\n", host, hwirq);
 600
 601         /* Look for default host if nececssary */
 602         if (host == NULL)
 603                 host = irq_default_host;
 604         if (host == NULL) {
 605                 printk(KERN_WARNING "irq_create_mapping called for"
 606                        " NULL host, hwirq=%lx\n", hwirq);
 607                 WARN_ON(1);
 608                 return NO_IRQ;
 609         }
 610         pr_debug("irq: -> using host @%p\n", host);
 611
 612         /* Check if mapping already exist, if it does, call
 613          * host->ops->map() to update the flags
 614          */
 615         virq = irq_find_mapping(host, hwirq);
 616         if (virq != NO_IRQ) {
 617                 if (host->ops->remap)
 618                         host->ops->remap(host, virq, hwirq);
 619                 pr_debug("irq: -> existing mapping on virq %d\n", virq);
 620                 return virq;
 621         }
 622
 623         /* Get a virtual interrupt number */
 624         if (host->revmap_type == IRQ_HOST_MAP_LEGACY) {
 625                 /* Handle legacy */
 626                 virq = (unsigned int)hwirq;
 627                 if (virq == 0 || virq >= NUM_ISA_INTERRUPTS)
 628                         return NO_IRQ;
 629                 return virq;
 630         } else {
 631                 /* Allocate a virtual interrupt number */
 632                 hint = hwirq % irq_virq_count;
 633                 virq = irq_alloc_virt(host, 1, hint);
 634                 if (virq == NO_IRQ) {
 635                         pr_debug("irq: -> virq allocation failed\n");
 636                         return NO_IRQ;
 637                 }
 638         }
 639         pr_debug("irq: -> obtained virq %d\n", virq);
 640
 641         /* Clear IRQ_NOREQUEST flag */
 642         get_irq_desc(virq)->status &= ~IRQ_NOREQUEST;
 643
 644         /* map it */
 645         smp_wmb();
 646         irq_map[virq].hwirq = hwirq;
 647         smp_mb();
 648         if (host->ops->map(host, virq, hwirq)) {
 649                 pr_debug("irq: -> mapping failed, freeing\n");
 650                 irq_free_virt(virq, 1);
 651                 return NO_IRQ;
 652         }
 653         return virq;
 654 }
 655 EXPORT_SYMBOL_GPL(irq_create_mapping);
 656
 657 unsigned int irq_create_of_mapping(struct device_node *controller,
 658                                    u32 *intspec, unsigned int intsize)
 659 {
 660         struct irq_host *host;
 661         irq_hw_number_t hwirq;
 662         unsigned int type = IRQ_TYPE_NONE;
 663         unsigned int virq;
 664
 665         if (controller == NULL)
 666                 host = irq_default_host;
 667         else
 668                 host = irq_find_host(controller);
 669         if (host == NULL) {
 670                 printk(KERN_WARNING "irq: no irq host found for %s !\n",
 671                        controller->full_name);
 672                 return NO_IRQ;
 673         }
 674
 675         /* If host has no translation, then we assume interrupt line */
 676         if (host->ops->xlate == NULL)
 677                 hwirq = intspec[0];
 678         else {
 679                 if (host->ops->xlate(host, controller, intspec, intsize,
 680                                      &hwirq, &type))
 681                         return NO_IRQ;
 682         }
 683
 684         /* Create mapping */
 685         virq = irq_create_mapping(host, hwirq);
 686         if (virq == NO_IRQ)
 687                 return virq;
 688
 689         /* Set type if specified and different than the current one */
 690         if (type != IRQ_TYPE_NONE &&
 691             type != (get_irq_desc(virq)->status & IRQF_TRIGGER_MASK))
 692                 set_irq_type(virq, type);
 693         return virq;
 694 }
 695 EXPORT_SYMBOL_GPL(irq_create_of_mapping);
 696
 697 unsigned int irq_of_parse_and_map(struct device_node *dev, int index)
 698 {
 699         struct of_irq oirq;
 700
 701         if (of_irq_map_one(dev, index, &oirq))
 702                 return NO_IRQ;
 703
 704         return irq_create_of_mapping(oirq.controller, oirq.specifier,
 705                                      oirq.size);
 706 }
 707 EXPORT_SYMBOL_GPL(irq_of_parse_and_map);
 708
 709 void irq_dispose_mapping(unsigned int virq)
 710 {
 711         struct irq_host *host;
 712         irq_hw_number_t hwirq;
 713         unsigned long flags;
 714
 715         if (virq == NO_IRQ)
 716                 return;
 717
 718         host = irq_map[virq].host;
 719         WARN_ON (host == NULL);
 720         if (host == NULL)
 721                 return;
 722
 723         /* Never unmap legacy interrupts */
 724         if (host->revmap_type == IRQ_HOST_MAP_LEGACY)
 725                 return;
 726
 727         /* remove chip and handler */
 728         set_irq_chip_and_handler(virq, NULL, NULL);
 729
 730         /* Make sure it's completed */
 731         synchronize_irq(virq);
 732
 733         /* Tell the PIC about it */
 734         if (host->ops->unmap)
 735                 host->ops->unmap(host, virq);
 736         smp_mb();
 737
 738         /* Clear reverse map */
 739         hwirq = irq_map[virq].hwirq;
 740         switch(host->revmap_type) {
 741         case IRQ_HOST_MAP_LINEAR:
 742                 if (hwirq < host->revmap_data.linear.size)
 743                         host->revmap_data.linear.revmap[hwirq] = NO_IRQ;
 744                 break;
 745         case IRQ_HOST_MAP_TREE:
 746                 /* Check if radix tree allocated yet */
 747                 if (host->revmap_data.tree.gfp_mask == 0)
 748                         break;
 749                 irq_radix_wrlock(&flags);
 750                 radix_tree_delete(&host->revmap_data.tree, hwirq);
 751                 irq_radix_wrunlock(flags);
 752                 break;
 753         }
 754
 755         /* Destroy map */
 756         smp_mb();
 757         irq_map[virq].hwirq = host->inval_irq;
 758
 759         /* Set some flags */
 760         get_irq_desc(virq)->status |= IRQ_NOREQUEST;
 761
 762         /* Free it */
 763         irq_free_virt(virq, 1);
 764 }
 765 EXPORT_SYMBOL_GPL(irq_dispose_mapping);
 766
 767 unsigned int irq_find_mapping(struct irq_host *host,
 768                               irq_hw_number_t hwirq)
 769 {
 770         unsigned int i;
 771         unsigned int hint = hwirq % irq_virq_count;
 772
 773         /* Look for default host if nececssary */
 774         if (host == NULL)
 775                 host = irq_default_host;
 776         if (host == NULL)
 777                 return NO_IRQ;
 778
 779         /* legacy -> bail early */
 780         if (host->revmap_type == IRQ_HOST_MAP_LEGACY)
 781                 return hwirq;
 782
 783         /* Slow path does a linear search of the map */
 784         if (hint < NUM_ISA_INTERRUPTS)
 785                 hint = NUM_ISA_INTERRUPTS;
 786         i = hint;
 787         do  {
 788                 if (irq_map[i].host == host &&
 789                     irq_map[i].hwirq == hwirq)
 790                         return i;
 791                 i++;
 792                 if (i >= irq_virq_count)
 793                         i = NUM_ISA_INTERRUPTS;
 794         } while(i != hint);
 795         return NO_IRQ;
 796 }
 797 EXPORT_SYMBOL_GPL(irq_find_mapping);
 798
 799
 800 unsigned int irq_radix_revmap(struct irq_host *host,
 801                               irq_hw_number_t hwirq)
 802 {
 803         struct radix_tree_root *tree;
 804         struct irq_map_entry *ptr;
 805         unsigned int virq;
 806         unsigned long flags;
 807
 808         WARN_ON(host->revmap_type != IRQ_HOST_MAP_TREE);
 809
 810         /* Check if the radix tree exist yet. We test the value of
 811          * the gfp_mask for that. Sneaky but saves another int in the
 812          * structure. If not, we fallback to slow mode
 813          */
 814         tree = &host->revmap_data.tree;
 815         if (tree->gfp_mask == 0)
 816                 return irq_find_mapping(host, hwirq);
 817
 818         /* Now try to resolve */
 819         irq_radix_rdlock(&flags);
 820         ptr = radix_tree_lookup(tree, hwirq);
 821         irq_radix_rdunlock(flags);
 822
 823         /* Found it, return */
 824         if (ptr) {
 825                 virq = ptr - irq_map;
 826                 return virq;
 827         }
 828
 829         /* If not there, try to insert it */
 830         virq = irq_find_mapping(host, hwirq);
 831         if (virq != NO_IRQ) {
 832                 irq_radix_wrlock(&flags);
 833                 radix_tree_insert(tree, hwirq, &irq_map[virq]);
 834                 irq_radix_wrunlock(flags);
 835         }
 836         return virq;
 837 }
 838
 839 unsigned int irq_linear_revmap(struct irq_host *host,
 840                                irq_hw_number_t hwirq)
 841 {
 842         unsigned int *revmap;
 843
 844         WARN_ON(host->revmap_type != IRQ_HOST_MAP_LINEAR);
 845
 846         /* Check revmap bounds */
 847         if (unlikely(hwirq >= host->revmap_data.linear.size))
 848                 return irq_find_mapping(host, hwirq);
 849
 850         /* Check if revmap was allocated */
 851         revmap = host->revmap_data.linear.revmap;
 852         if (unlikely(revmap == NULL))
 853                 return irq_find_mapping(host, hwirq);
 854
 855         /* Fill up revmap with slow path if no mapping found */
 856         if (unlikely(revmap[hwirq] == NO_IRQ))
 857                 revmap[hwirq] = irq_find_mapping(host, hwirq);
 858
 859         return revmap[hwirq];
 860 }
 861
 862 unsigned int irq_alloc_virt(struct irq_host *host,
 863                             unsigned int count,
 864                             unsigned int hint)
 865 {
 866         unsigned long flags;
 867         unsigned int i, j, found = NO_IRQ;
 868
 869         if (count == 0 || count > (irq_virq_count - NUM_ISA_INTERRUPTS))
 870                 return NO_IRQ;
 871
 872         spin_lock_irqsave(&irq_big_lock, flags);
 873
 874         /* Use hint for 1 interrupt if any */
 875         if (count == 1 && hint >= NUM_ISA_INTERRUPTS &&
 876             hint < irq_virq_count && irq_map[hint].host == NULL) {
 877                 found = hint;
 878                 goto hint_found;
 879         }
 880
 881         /* Look for count consecutive numbers in the allocatable
 882          * (non-legacy) space
 883          */
 884         for (i = NUM_ISA_INTERRUPTS, j = 0; i < irq_virq_count; i++) {
 885                 if (irq_map[i].host != NULL)
 886                         j = 0;
 887                 else
 888                         j++;
 889
 890                 if (j == count) {
 891                         found = i - count + 1;
 892                         break;
 893                 }
 894         }
 895         if (found == NO_IRQ) {
 896                 spin_unlock_irqrestore(&irq_big_lock, flags);
 897                 return NO_IRQ;
 898         }
 899  hint_found:
 900         for (i = found; i < (found + count); i++) {
 901                 irq_map[i].hwirq = host->inval_irq;
 902                 smp_wmb();
 903                 irq_map[i].host = host;
 904         }
 905         spin_unlock_irqrestore(&irq_big_lock, flags);
 906         return found;
 907 }
 908
 909 void irq_free_virt(unsigned int virq, unsigned int count)
 910 {
 911         unsigned long flags;
 912         unsigned int i;
 913
 914         WARN_ON (virq < NUM_ISA_INTERRUPTS);
 915         WARN_ON (count == 0 || (virq + count) > irq_virq_count);
 916
 917         spin_lock_irqsave(&irq_big_lock, flags);
 918         for (i = virq; i < (virq + count); i++) {
 919                 struct irq_host *host;
 920
 921                 if (i < NUM_ISA_INTERRUPTS ||
 922                     (virq + count) > irq_virq_count)
 923                         continue;
 924
 925                 host = irq_map[i].host;
 926                 irq_map[i].hwirq = host->inval_irq;
 927                 smp_wmb();
 928                 irq_map[i].host = NULL;
 929         }
 930         spin_unlock_irqrestore(&irq_big_lock, flags);
 931 }
 932
 933 void irq_early_init(void)
 934 {
 935         unsigned int i;
 936
 937         for (i = 0; i < NR_IRQS; i++)
 938                 get_irq_desc(i)->status |= IRQ_NOREQUEST;
 939 }
 940
 941 /* We need to create the radix trees late */
 942 static int irq_late_init(void)
 943 {
 944         struct irq_host *h;
 945         unsigned long flags;
 946
 947         irq_radix_wrlock(&flags);
 948         list_for_each_entry(h, &irq_hosts, link) {
 949                 if (h->revmap_type == IRQ_HOST_MAP_TREE)
 950                         INIT_RADIX_TREE(&h->revmap_data.tree, GFP_ATOMIC);
 951         }
 952         irq_radix_wrunlock(flags);
 953
 954         return 0;
 955 }
 956 arch_initcall(irq_late_init);
 957
 958 #endif /* CONFIG_PPC_MERGE */
 959
 960 #ifdef CONFIG_PPC64
 961 static int __init setup_noirqdistrib(char *str)
 962 {
 963         distribute_irqs = 0;
 964         return 1;
 965 }
 966
 967 __setup("noirqdistrib", setup_noirqdistrib);
 968 #endif /* CONFIG_PPC64 */