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 #include <linux/debugfs.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_PPC64
  68 #include <asm/paca.h>
  69 #include <asm/firmware.h>
  70 #include <asm/lv1call.h>
  71 #endif
  72
  73 int __irq_offset_value;
  74 static int ppc_spurious_interrupts;
  75
  76 #ifdef CONFIG_PPC32
  77 EXPORT_SYMBOL(__irq_offset_value);
  78 atomic_t ppc_n_lost_interrupts;
  79
  80 #ifndef CONFIG_PPC_MERGE
  81 #define NR_MASK_WORDS   ((NR_IRQS + 31) / 32)
  82 unsigned long ppc_cached_irq_mask[NR_MASK_WORDS];
  83 #endif
  84
  85 #ifdef CONFIG_TAU_INT
  86 extern int tau_initialized;
  87 extern int tau_interrupts(int);
  88 #endif
  89 #endif /* CONFIG_PPC32 */
  90
  91 #if defined(CONFIG_SMP) && !defined(CONFIG_PPC_MERGE)
  92 extern atomic_t ipi_recv;
  93 extern atomic_t ipi_sent;
  94 #endif
  95
  96 #ifdef CONFIG_PPC64
  97 EXPORT_SYMBOL(irq_desc);
  98
  99 int distribute_irqs = 1;
 100
 101 static inline notrace unsigned long get_hard_enabled(void)
 102 {
 103         unsigned long enabled;
 104
 105         __asm__ __volatile__("lbz %0,%1(13)"
 106         : "=r" (enabled) : "i" (offsetof(struct paca_struct, hard_enabled)));
 107
 108         return enabled;
 109 }
 110
 111 static inline notrace void set_soft_enabled(unsigned long enable)
 112 {
 113         __asm__ __volatile__("stb %0,%1(13)"
 114         : : "r" (enable), "i" (offsetof(struct paca_struct, soft_enabled)));
 115 }
 116
 117 notrace void raw_local_irq_restore(unsigned long en)
 118 {
 119         /*
 120          * get_paca()->soft_enabled = en;
 121          * Is it ever valid to use local_irq_restore(0) when soft_enabled is 1?
 122          * That was allowed before, and in such a case we do need to take care
 123          * that gcc will set soft_enabled directly via r13, not choose to use
 124          * an intermediate register, lest we're preempted to a different cpu.
 125          */
 126         set_soft_enabled(en);
 127         if (!en)
 128                 return;
 129
 130         if (firmware_has_feature(FW_FEATURE_ISERIES)) {
 131                 /*
 132                  * Do we need to disable preemption here?  Not really: in the
 133                  * unlikely event that we're preempted to a different cpu in
 134                  * between getting r13, loading its lppaca_ptr, and loading
 135                  * its any_int, we might call iseries_handle_interrupts without
 136                  * an interrupt pending on the new cpu, but that's no disaster,
 137                  * is it?  And the business of preempting us off the old cpu
 138                  * would itself involve a local_irq_restore which handles the
 139                  * interrupt to that cpu.
 140                  *
 141                  * But use "local_paca->lppaca_ptr" instead of "get_lppaca()"
 142                  * to avoid any preemption checking added into get_paca().
 143                  */
 144                 if (local_paca->lppaca_ptr->int_dword.any_int)
 145                         iseries_handle_interrupts();
 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 EXPORT_SYMBOL(raw_local_irq_restore);
 178 #endif /* CONFIG_PPC64 */
 179
 180 int show_interrupts(struct seq_file *p, void *v)
 181 {
 182         int i = *(loff_t *)v, j;
 183         struct irqaction *action;
 184         irq_desc_t *desc;
 185         unsigned long flags;
 186
 187         if (i == 0) {
 188                 seq_puts(p, "           ");
 189                 for_each_online_cpu(j)
 190                         seq_printf(p, "CPU%d       ", j);
 191                 seq_putc(p, '\n');
 192         }
 193
 194         if (i < NR_IRQS) {
 195                 desc = get_irq_desc(i);
 196                 spin_lock_irqsave(&desc->lock, flags);
 197                 action = desc->action;
 198                 if (!action || !action->handler)
 199                         goto skip;
 200                 seq_printf(p, "%3d: ", i);
 201 #ifdef CONFIG_SMP
 202                 for_each_online_cpu(j)
 203                         seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
 204 #else
 205                 seq_printf(p, "%10u ", kstat_irqs(i));
 206 #endif /* CONFIG_SMP */
 207                 if (desc->chip)
 208                         seq_printf(p, " %s ", desc->chip->typename);
 209                 else
 210                         seq_puts(p, "  None      ");
 211                 seq_printf(p, "%s", (desc->status & IRQ_LEVEL) ? "Level " : "Edge  ");
 212                 seq_printf(p, "    %s", action->name);
 213                 for (action = action->next; action; action = action->next)
 214                         seq_printf(p, ", %s", action->name);
 215                 seq_putc(p, '\n');
 216 skip:
 217                 spin_unlock_irqrestore(&desc->lock, flags);
 218         } else if (i == NR_IRQS) {
 219 #ifdef CONFIG_PPC32
 220 #ifdef CONFIG_TAU_INT
 221                 if (tau_initialized){
 222                         seq_puts(p, "TAU: ");
 223                         for_each_online_cpu(j)
 224                                 seq_printf(p, "%10u ", tau_interrupts(j));
 225                         seq_puts(p, "  PowerPC             Thermal Assist (cpu temp)\n");
 226                 }
 227 #endif
 228 #if defined(CONFIG_SMP) && !defined(CONFIG_PPC_MERGE)
 229                 /* should this be per processor send/receive? */
 230                 seq_printf(p, "IPI (recv/sent): %10u/%u\n",
 231                                 atomic_read(&ipi_recv), atomic_read(&ipi_sent));
 232 #endif
 233 #endif /* CONFIG_PPC32 */
 234                 seq_printf(p, "BAD: %10u\n", ppc_spurious_interrupts);
 235         }
 236         return 0;
 237 }
 238
 239 #ifdef CONFIG_HOTPLUG_CPU
 240 void fixup_irqs(cpumask_t map)
 241 {
 242         unsigned int irq;
 243         static int warned;
 244
 245         for_each_irq(irq) {
 246                 cpumask_t mask;
 247
 248                 if (irq_desc[irq].status & IRQ_PER_CPU)
 249                         continue;
 250
 251                 cpus_and(mask, irq_desc[irq].affinity, map);
 252                 if (any_online_cpu(mask) == NR_CPUS) {
 253                         printk("Breaking affinity for irq %i\n", irq);
 254                         mask = map;
 255                 }
 256                 if (irq_desc[irq].chip->set_affinity)
 257                         irq_desc[irq].chip->set_affinity(irq, mask);
 258                 else if (irq_desc[irq].action && !(warned++))
 259                         printk("Cannot set affinity for irq %i\n", irq);
 260         }
 261
 262         local_irq_enable();
 263         mdelay(1);
 264         local_irq_disable();
 265 }
 266 #endif
 267
 268 void do_IRQ(struct pt_regs *regs)
 269 {
 270         struct pt_regs *old_regs = set_irq_regs(regs);
 271         unsigned int irq;
 272 #ifdef CONFIG_IRQSTACKS
 273         struct thread_info *curtp, *irqtp;
 274 #endif
 275
 276         irq_enter();
 277
 278 #ifdef CONFIG_DEBUG_STACKOVERFLOW
 279         /* Debugging check for stack overflow: is there less than 2KB free? */
 280         {
 281                 long sp;
 282
 283                 sp = __get_SP() & (THREAD_SIZE-1);
 284
 285                 if (unlikely(sp < (sizeof(struct thread_info) + 2048))) {
 286                         printk("do_IRQ: stack overflow: %ld\n",
 287                                 sp - sizeof(struct thread_info));
 288                         dump_stack();
 289                 }
 290         }
 291 #endif
 292
 293         /*
 294          * Every platform is required to implement ppc_md.get_irq.
 295          * This function will either return an irq number or NO_IRQ to
 296          * indicate there are no more pending.
 297          * The value NO_IRQ_IGNORE is for buggy hardware and means that this
 298          * IRQ has already been handled. -- Tom
 299          */
 300         irq = ppc_md.get_irq();
 301
 302         if (irq != NO_IRQ && irq != NO_IRQ_IGNORE) {
 303 #ifdef CONFIG_IRQSTACKS
 304                 /* Switch to the irq stack to handle this */
 305                 curtp = current_thread_info();
 306                 irqtp = hardirq_ctx[smp_processor_id()];
 307                 if (curtp != irqtp) {
 308                         struct irq_desc *desc = irq_desc + irq;
 309                         void *handler = desc->handle_irq;
 310                         unsigned long saved_sp_limit = current->thread.ksp_limit;
 311                         if (handler == NULL)
 312                                 handler = &__do_IRQ;
 313                         irqtp->task = curtp->task;
 314                         irqtp->flags = 0;
 315
 316                         /* Copy the softirq bits in preempt_count so that the
 317                          * softirq checks work in the hardirq context.
 318                          */
 319                         irqtp->preempt_count =
 320                                 (irqtp->preempt_count & ~SOFTIRQ_MASK) |
 321                                 (curtp->preempt_count & SOFTIRQ_MASK);
 322
 323                         current->thread.ksp_limit = (unsigned long)irqtp +
 324                                 _ALIGN_UP(sizeof(struct thread_info), 16);
 325                         call_handle_irq(irq, desc, irqtp, handler);
 326                         current->thread.ksp_limit = saved_sp_limit;
 327                         irqtp->task = NULL;
 328
 329
 330                         /* Set any flag that may have been set on the
 331                          * alternate stack
 332                          */
 333                         if (irqtp->flags)
 334                                 set_bits(irqtp->flags, &curtp->flags);
 335                 } else
 336 #endif
 337                         generic_handle_irq(irq);
 338         } else if (irq != NO_IRQ_IGNORE)
 339                 /* That's not SMP safe ... but who cares ? */
 340                 ppc_spurious_interrupts++;
 341
 342         irq_exit();
 343         set_irq_regs(old_regs);
 344
 345 #ifdef CONFIG_PPC_ISERIES
 346         if (firmware_has_feature(FW_FEATURE_ISERIES) &&
 347                         get_lppaca()->int_dword.fields.decr_int) {
 348                 get_lppaca()->int_dword.fields.decr_int = 0;
 349                 /* Signal a fake decrementer interrupt */
 350                 timer_interrupt(regs);
 351         }
 352 #endif
 353 }
 354
 355 void __init init_IRQ(void)
 356 {
 357         if (ppc_md.init_IRQ)
 358                 ppc_md.init_IRQ();
 359         irq_ctx_init();
 360 }
 361
 362
 363 #ifdef CONFIG_IRQSTACKS
 364 struct thread_info *softirq_ctx[NR_CPUS] __read_mostly;
 365 struct thread_info *hardirq_ctx[NR_CPUS] __read_mostly;
 366
 367 void irq_ctx_init(void)
 368 {
 369         struct thread_info *tp;
 370         int i;
 371
 372         for_each_possible_cpu(i) {
 373                 memset((void *)softirq_ctx[i], 0, THREAD_SIZE);
 374                 tp = softirq_ctx[i];
 375                 tp->cpu = i;
 376                 tp->preempt_count = 0;
 377
 378                 memset((void *)hardirq_ctx[i], 0, THREAD_SIZE);
 379                 tp = hardirq_ctx[i];
 380                 tp->cpu = i;
 381                 tp->preempt_count = HARDIRQ_OFFSET;
 382         }
 383 }
 384
 385 static inline void do_softirq_onstack(void)
 386 {
 387         struct thread_info *curtp, *irqtp;
 388         unsigned long saved_sp_limit = current->thread.ksp_limit;
 389
 390         curtp = current_thread_info();
 391         irqtp = softirq_ctx[smp_processor_id()];
 392         irqtp->task = curtp->task;
 393         current->thread.ksp_limit = (unsigned long)irqtp +
 394                                     _ALIGN_UP(sizeof(struct thread_info), 16);
 395         call_do_softirq(irqtp);
 396         current->thread.ksp_limit = saved_sp_limit;
 397         irqtp->task = NULL;
 398 }
 399
 400 #else
 401 #define do_softirq_onstack()    __do_softirq()
 402 #endif /* CONFIG_IRQSTACKS */
 403
 404 void do_softirq(void)
 405 {
 406         unsigned long flags;
 407
 408         if (in_interrupt())
 409                 return;
 410
 411         local_irq_save(flags);
 412
 413         if (local_softirq_pending())
 414                 do_softirq_onstack();
 415
 416         local_irq_restore(flags);
 417 }
 418
 419
 420 /*
 421  * IRQ controller and virtual interrupts
 422  */
 423
 424 #ifdef CONFIG_PPC_MERGE
 425
 426 static LIST_HEAD(irq_hosts);
 427 static DEFINE_SPINLOCK(irq_big_lock);
 428 static DEFINE_PER_CPU(unsigned int, irq_radix_reader);
 429 static unsigned int irq_radix_writer;
 430 struct irq_map_entry irq_map[NR_IRQS];
 431 static unsigned int irq_virq_count = NR_IRQS;
 432 static struct irq_host *irq_default_host;
 433
 434 irq_hw_number_t virq_to_hw(unsigned int virq)
 435 {
 436         return irq_map[virq].hwirq;
 437 }
 438 EXPORT_SYMBOL_GPL(virq_to_hw);
 439
 440 static int default_irq_host_match(struct irq_host *h, struct device_node *np)
 441 {
 442         return h->of_node != NULL && h->of_node == np;
 443 }
 444
 445 struct irq_host *irq_alloc_host(struct device_node *of_node,
 446                                 unsigned int revmap_type,
 447                                 unsigned int revmap_arg,
 448                                 struct irq_host_ops *ops,
 449                                 irq_hw_number_t inval_irq)
 450 {
 451         struct irq_host *host;
 452         unsigned int size = sizeof(struct irq_host);
 453         unsigned int i;
 454         unsigned int *rmap;
 455         unsigned long flags;
 456
 457         /* Allocate structure and revmap table if using linear mapping */
 458         if (revmap_type == IRQ_HOST_MAP_LINEAR)
 459                 size += revmap_arg * sizeof(unsigned int);
 460         host = zalloc_maybe_bootmem(size, GFP_KERNEL);
 461         if (host == NULL)
 462                 return NULL;
 463
 464         /* Fill structure */
 465         host->revmap_type = revmap_type;
 466         host->inval_irq = inval_irq;
 467         host->ops = ops;
 468         host->of_node = of_node;
 469
 470         if (host->ops->match == NULL)
 471                 host->ops->match = default_irq_host_match;
 472
 473         spin_lock_irqsave(&irq_big_lock, flags);
 474
 475         /* If it's a legacy controller, check for duplicates and
 476          * mark it as allocated (we use irq 0 host pointer for that
 477          */
 478         if (revmap_type == IRQ_HOST_MAP_LEGACY) {
 479                 if (irq_map[0].host != NULL) {
 480                         spin_unlock_irqrestore(&irq_big_lock, flags);
 481                         /* If we are early boot, we can't free the structure,
 482                          * too bad...
 483                          * this will be fixed once slab is made available early
 484                          * instead of the current cruft
 485                          */
 486                         if (mem_init_done)
 487                                 kfree(host);
 488                         return NULL;
 489                 }
 490                 irq_map[0].host = host;
 491         }
 492
 493         list_add(&host->link, &irq_hosts);
 494         spin_unlock_irqrestore(&irq_big_lock, flags);
 495
 496         /* Additional setups per revmap type */
 497         switch(revmap_type) {
 498         case IRQ_HOST_MAP_LEGACY:
 499                 /* 0 is always the invalid number for legacy */
 500                 host->inval_irq = 0;
 501                 /* setup us as the host for all legacy interrupts */
 502                 for (i = 1; i < NUM_ISA_INTERRUPTS; i++) {
 503                         irq_map[i].hwirq = i;
 504                         smp_wmb();
 505                         irq_map[i].host = host;
 506                         smp_wmb();
 507
 508                         /* Clear norequest flags */
 509                         get_irq_desc(i)->status &= ~IRQ_NOREQUEST;
 510
 511                         /* Legacy flags are left to default at this point,
 512                          * one can then use irq_create_mapping() to
 513                          * explicitly change them
 514                          */
 515                         ops->map(host, i, i);
 516                 }
 517                 break;
 518         case IRQ_HOST_MAP_LINEAR:
 519                 rmap = (unsigned int *)(host + 1);
 520                 for (i = 0; i < revmap_arg; i++)
 521                         rmap[i] = NO_IRQ;
 522                 host->revmap_data.linear.size = revmap_arg;
 523                 smp_wmb();
 524                 host->revmap_data.linear.revmap = rmap;
 525                 break;
 526         default:
 527                 break;
 528         }
 529
 530         pr_debug("irq: Allocated host of type %d @0x%p\n", revmap_type, host);
 531
 532         return host;
 533 }
 534
 535 struct irq_host *irq_find_host(struct device_node *node)
 536 {
 537         struct irq_host *h, *found = NULL;
 538         unsigned long flags;
 539
 540         /* We might want to match the legacy controller last since
 541          * it might potentially be set to match all interrupts in
 542          * the absence of a device node. This isn't a problem so far
 543          * yet though...
 544          */
 545         spin_lock_irqsave(&irq_big_lock, flags);
 546         list_for_each_entry(h, &irq_hosts, link)
 547                 if (h->ops->match(h, node)) {
 548                         found = h;
 549                         break;
 550                 }
 551         spin_unlock_irqrestore(&irq_big_lock, flags);
 552         return found;
 553 }
 554 EXPORT_SYMBOL_GPL(irq_find_host);
 555
 556 void irq_set_default_host(struct irq_host *host)
 557 {
 558         pr_debug("irq: Default host set to @0x%p\n", host);
 559
 560         irq_default_host = host;
 561 }
 562
 563 void irq_set_virq_count(unsigned int count)
 564 {
 565         pr_debug("irq: Trying to set virq count to %d\n", count);
 566
 567         BUG_ON(count < NUM_ISA_INTERRUPTS);
 568         if (count < NR_IRQS)
 569                 irq_virq_count = count;
 570 }
 571
 572 /* radix tree not lockless safe ! we use a brlock-type mecanism
 573  * for now, until we can use a lockless radix tree
 574  */
 575 static void irq_radix_wrlock(unsigned long *flags)
 576 {
 577         unsigned int cpu, ok;
 578
 579         spin_lock_irqsave(&irq_big_lock, *flags);
 580         irq_radix_writer = 1;
 581         smp_mb();
 582         do {
 583                 barrier();
 584                 ok = 1;
 585                 for_each_possible_cpu(cpu) {
 586                         if (per_cpu(irq_radix_reader, cpu)) {
 587                                 ok = 0;
 588                                 break;
 589                         }
 590                 }
 591                 if (!ok)
 592                         cpu_relax();
 593         } while(!ok);
 594 }
 595
 596 static void irq_radix_wrunlock(unsigned long flags)
 597 {
 598         smp_wmb();
 599         irq_radix_writer = 0;
 600         spin_unlock_irqrestore(&irq_big_lock, flags);
 601 }
 602
 603 static void irq_radix_rdlock(unsigned long *flags)
 604 {
 605         local_irq_save(*flags);
 606         __get_cpu_var(irq_radix_reader) = 1;
 607         smp_mb();
 608         if (likely(irq_radix_writer == 0))
 609                 return;
 610         __get_cpu_var(irq_radix_reader) = 0;
 611         smp_wmb();
 612         spin_lock(&irq_big_lock);
 613         __get_cpu_var(irq_radix_reader) = 1;
 614         spin_unlock(&irq_big_lock);
 615 }
 616
 617 static void irq_radix_rdunlock(unsigned long flags)
 618 {
 619         __get_cpu_var(irq_radix_reader) = 0;
 620         local_irq_restore(flags);
 621 }
 622
 623 static int irq_setup_virq(struct irq_host *host, unsigned int virq,
 624                             irq_hw_number_t hwirq)
 625 {
 626         /* Clear IRQ_NOREQUEST flag */
 627         get_irq_desc(virq)->status &= ~IRQ_NOREQUEST;
 628
 629         /* map it */
 630         smp_wmb();
 631         irq_map[virq].hwirq = hwirq;
 632         smp_mb();
 633
 634         if (host->ops->map(host, virq, hwirq)) {
 635                 pr_debug("irq: -> mapping failed, freeing\n");
 636                 irq_free_virt(virq, 1);
 637                 return -1;
 638         }
 639
 640         return 0;
 641 }
 642
 643 unsigned int irq_create_direct_mapping(struct irq_host *host)
 644 {
 645         unsigned int virq;
 646
 647         if (host == NULL)
 648                 host = irq_default_host;
 649
 650         BUG_ON(host == NULL);
 651         WARN_ON(host->revmap_type != IRQ_HOST_MAP_NOMAP);
 652
 653         virq = irq_alloc_virt(host, 1, 0);
 654         if (virq == NO_IRQ) {
 655                 pr_debug("irq: create_direct virq allocation failed\n");
 656                 return NO_IRQ;
 657         }
 658
 659         pr_debug("irq: create_direct obtained virq %d\n", virq);
 660
 661         if (irq_setup_virq(host, virq, virq))
 662                 return NO_IRQ;
 663
 664         return virq;
 665 }
 666
 667 unsigned int irq_create_mapping(struct irq_host *host,
 668                                 irq_hw_number_t hwirq)
 669 {
 670         unsigned int virq, hint;
 671
 672         pr_debug("irq: irq_create_mapping(0x%p, 0x%lx)\n", host, hwirq);
 673
 674         /* Look for default host if nececssary */
 675         if (host == NULL)
 676                 host = irq_default_host;
 677         if (host == NULL) {
 678                 printk(KERN_WARNING "irq_create_mapping called for"
 679                        " NULL host, hwirq=%lx\n", hwirq);
 680                 WARN_ON(1);
 681                 return NO_IRQ;
 682         }
 683         pr_debug("irq: -> using host @%p\n", host);
 684
 685         /* Check if mapping already exist, if it does, call
 686          * host->ops->map() to update the flags
 687          */
 688         virq = irq_find_mapping(host, hwirq);
 689         if (virq != NO_IRQ) {
 690                 if (host->ops->remap)
 691                         host->ops->remap(host, virq, hwirq);
 692                 pr_debug("irq: -> existing mapping on virq %d\n", virq);
 693                 return virq;
 694         }
 695
 696         /* Get a virtual interrupt number */
 697         if (host->revmap_type == IRQ_HOST_MAP_LEGACY) {
 698                 /* Handle legacy */
 699                 virq = (unsigned int)hwirq;
 700                 if (virq == 0 || virq >= NUM_ISA_INTERRUPTS)
 701                         return NO_IRQ;
 702                 return virq;
 703         } else {
 704                 /* Allocate a virtual interrupt number */
 705                 hint = hwirq % irq_virq_count;
 706                 virq = irq_alloc_virt(host, 1, hint);
 707                 if (virq == NO_IRQ) {
 708                         pr_debug("irq: -> virq allocation failed\n");
 709                         return NO_IRQ;
 710                 }
 711         }
 712         pr_debug("irq: -> obtained virq %d\n", virq);
 713
 714         if (irq_setup_virq(host, virq, hwirq))
 715                 return NO_IRQ;
 716
 717         return virq;
 718 }
 719 EXPORT_SYMBOL_GPL(irq_create_mapping);
 720
 721 unsigned int irq_create_of_mapping(struct device_node *controller,
 722                                    u32 *intspec, unsigned int intsize)
 723 {
 724         struct irq_host *host;
 725         irq_hw_number_t hwirq;
 726         unsigned int type = IRQ_TYPE_NONE;
 727         unsigned int virq;
 728
 729         if (controller == NULL)
 730                 host = irq_default_host;
 731         else
 732                 host = irq_find_host(controller);
 733         if (host == NULL) {
 734                 printk(KERN_WARNING "irq: no irq host found for %s !\n",
 735                        controller->full_name);
 736                 return NO_IRQ;
 737         }
 738
 739         /* If host has no translation, then we assume interrupt line */
 740         if (host->ops->xlate == NULL)
 741                 hwirq = intspec[0];
 742         else {
 743                 if (host->ops->xlate(host, controller, intspec, intsize,
 744                                      &hwirq, &type))
 745                         return NO_IRQ;
 746         }
 747
 748         /* Create mapping */
 749         virq = irq_create_mapping(host, hwirq);
 750         if (virq == NO_IRQ)
 751                 return virq;
 752
 753         /* Set type if specified and different than the current one */
 754         if (type != IRQ_TYPE_NONE &&
 755             type != (get_irq_desc(virq)->status & IRQF_TRIGGER_MASK))
 756                 set_irq_type(virq, type);
 757         return virq;
 758 }
 759 EXPORT_SYMBOL_GPL(irq_create_of_mapping);
 760
 761 unsigned int irq_of_parse_and_map(struct device_node *dev, int index)
 762 {
 763         struct of_irq oirq;
 764
 765         if (of_irq_map_one(dev, index, &oirq))
 766                 return NO_IRQ;
 767
 768         return irq_create_of_mapping(oirq.controller, oirq.specifier,
 769                                      oirq.size);
 770 }
 771 EXPORT_SYMBOL_GPL(irq_of_parse_and_map);
 772
 773 void irq_dispose_mapping(unsigned int virq)
 774 {
 775         struct irq_host *host;
 776         irq_hw_number_t hwirq;
 777         unsigned long flags;
 778
 779         if (virq == NO_IRQ)
 780                 return;
 781
 782         host = irq_map[virq].host;
 783         WARN_ON (host == NULL);
 784         if (host == NULL)
 785                 return;
 786
 787         /* Never unmap legacy interrupts */
 788         if (host->revmap_type == IRQ_HOST_MAP_LEGACY)
 789                 return;
 790
 791         /* remove chip and handler */
 792         set_irq_chip_and_handler(virq, NULL, NULL);
 793
 794         /* Make sure it's completed */
 795         synchronize_irq(virq);
 796
 797         /* Tell the PIC about it */
 798         if (host->ops->unmap)
 799                 host->ops->unmap(host, virq);
 800         smp_mb();
 801
 802         /* Clear reverse map */
 803         hwirq = irq_map[virq].hwirq;
 804         switch(host->revmap_type) {
 805         case IRQ_HOST_MAP_LINEAR:
 806                 if (hwirq < host->revmap_data.linear.size)
 807                         host->revmap_data.linear.revmap[hwirq] = NO_IRQ;
 808                 break;
 809         case IRQ_HOST_MAP_TREE:
 810                 /* Check if radix tree allocated yet */
 811                 if (host->revmap_data.tree.gfp_mask == 0)
 812                         break;
 813                 irq_radix_wrlock(&flags);
 814                 radix_tree_delete(&host->revmap_data.tree, hwirq);
 815                 irq_radix_wrunlock(flags);
 816                 break;
 817         }
 818
 819         /* Destroy map */
 820         smp_mb();
 821         irq_map[virq].hwirq = host->inval_irq;
 822
 823         /* Set some flags */
 824         get_irq_desc(virq)->status |= IRQ_NOREQUEST;
 825
 826         /* Free it */
 827         irq_free_virt(virq, 1);
 828 }
 829 EXPORT_SYMBOL_GPL(irq_dispose_mapping);
 830
 831 unsigned int irq_find_mapping(struct irq_host *host,
 832                               irq_hw_number_t hwirq)
 833 {
 834         unsigned int i;
 835         unsigned int hint = hwirq % irq_virq_count;
 836
 837         /* Look for default host if nececssary */
 838         if (host == NULL)
 839                 host = irq_default_host;
 840         if (host == NULL)
 841                 return NO_IRQ;
 842
 843         /* legacy -> bail early */
 844         if (host->revmap_type == IRQ_HOST_MAP_LEGACY)
 845                 return hwirq;
 846
 847         /* Slow path does a linear search of the map */
 848         if (hint < NUM_ISA_INTERRUPTS)
 849                 hint = NUM_ISA_INTERRUPTS;
 850         i = hint;
 851         do  {
 852                 if (irq_map[i].host == host &&
 853                     irq_map[i].hwirq == hwirq)
 854                         return i;
 855                 i++;
 856                 if (i >= irq_virq_count)
 857                         i = NUM_ISA_INTERRUPTS;
 858         } while(i != hint);
 859         return NO_IRQ;
 860 }
 861 EXPORT_SYMBOL_GPL(irq_find_mapping);
 862
 863
 864 unsigned int irq_radix_revmap(struct irq_host *host,
 865                               irq_hw_number_t hwirq)
 866 {
 867         struct radix_tree_root *tree;
 868         struct irq_map_entry *ptr;
 869         unsigned int virq;
 870         unsigned long flags;
 871
 872         WARN_ON(host->revmap_type != IRQ_HOST_MAP_TREE);
 873
 874         /* Check if the radix tree exist yet. We test the value of
 875          * the gfp_mask for that. Sneaky but saves another int in the
 876          * structure. If not, we fallback to slow mode
 877          */
 878         tree = &host->revmap_data.tree;
 879         if (tree->gfp_mask == 0)
 880                 return irq_find_mapping(host, hwirq);
 881
 882         /* Now try to resolve */
 883         irq_radix_rdlock(&flags);
 884         ptr = radix_tree_lookup(tree, hwirq);
 885         irq_radix_rdunlock(flags);
 886
 887         /* Found it, return */
 888         if (ptr) {
 889                 virq = ptr - irq_map;
 890                 return virq;
 891         }
 892
 893         /* If not there, try to insert it */
 894         virq = irq_find_mapping(host, hwirq);
 895         if (virq != NO_IRQ) {
 896                 irq_radix_wrlock(&flags);
 897                 radix_tree_insert(tree, hwirq, &irq_map[virq]);
 898                 irq_radix_wrunlock(flags);
 899         }
 900         return virq;
 901 }
 902
 903 unsigned int irq_linear_revmap(struct irq_host *host,
 904                                irq_hw_number_t hwirq)
 905 {
 906         unsigned int *revmap;
 907
 908         WARN_ON(host->revmap_type != IRQ_HOST_MAP_LINEAR);
 909
 910         /* Check revmap bounds */
 911         if (unlikely(hwirq >= host->revmap_data.linear.size))
 912                 return irq_find_mapping(host, hwirq);
 913
 914         /* Check if revmap was allocated */
 915         revmap = host->revmap_data.linear.revmap;
 916         if (unlikely(revmap == NULL))
 917                 return irq_find_mapping(host, hwirq);
 918
 919         /* Fill up revmap with slow path if no mapping found */
 920         if (unlikely(revmap[hwirq] == NO_IRQ))
 921                 revmap[hwirq] = irq_find_mapping(host, hwirq);
 922
 923         return revmap[hwirq];
 924 }
 925
 926 unsigned int irq_alloc_virt(struct irq_host *host,
 927                             unsigned int count,
 928                             unsigned int hint)
 929 {
 930         unsigned long flags;
 931         unsigned int i, j, found = NO_IRQ;
 932
 933         if (count == 0 || count > (irq_virq_count - NUM_ISA_INTERRUPTS))
 934                 return NO_IRQ;
 935
 936         spin_lock_irqsave(&irq_big_lock, flags);
 937
 938         /* Use hint for 1 interrupt if any */
 939         if (count == 1 && hint >= NUM_ISA_INTERRUPTS &&
 940             hint < irq_virq_count && irq_map[hint].host == NULL) {
 941                 found = hint;
 942                 goto hint_found;
 943         }
 944
 945         /* Look for count consecutive numbers in the allocatable
 946          * (non-legacy) space
 947          */
 948         for (i = NUM_ISA_INTERRUPTS, j = 0; i < irq_virq_count; i++) {
 949                 if (irq_map[i].host != NULL)
 950                         j = 0;
 951                 else
 952                         j++;
 953
 954                 if (j == count) {
 955                         found = i - count + 1;
 956                         break;
 957                 }
 958         }
 959         if (found == NO_IRQ) {
 960                 spin_unlock_irqrestore(&irq_big_lock, flags);
 961                 return NO_IRQ;
 962         }
 963  hint_found:
 964         for (i = found; i < (found + count); i++) {
 965                 irq_map[i].hwirq = host->inval_irq;
 966                 smp_wmb();
 967                 irq_map[i].host = host;
 968         }
 969         spin_unlock_irqrestore(&irq_big_lock, flags);
 970         return found;
 971 }
 972
 973 void irq_free_virt(unsigned int virq, unsigned int count)
 974 {
 975         unsigned long flags;
 976         unsigned int i;
 977
 978         WARN_ON (virq < NUM_ISA_INTERRUPTS);
 979         WARN_ON (count == 0 || (virq + count) > irq_virq_count);
 980
 981         spin_lock_irqsave(&irq_big_lock, flags);
 982         for (i = virq; i < (virq + count); i++) {
 983                 struct irq_host *host;
 984
 985                 if (i < NUM_ISA_INTERRUPTS ||
 986                     (virq + count) > irq_virq_count)
 987                         continue;
 988
 989                 host = irq_map[i].host;
 990                 irq_map[i].hwirq = host->inval_irq;
 991                 smp_wmb();
 992                 irq_map[i].host = NULL;
 993         }
 994         spin_unlock_irqrestore(&irq_big_lock, flags);
 995 }
 996
 997 void irq_early_init(void)
 998 {
 999         unsigned int i;
1000
1001         for (i = 0; i < NR_IRQS; i++)
1002                 get_irq_desc(i)->status |= IRQ_NOREQUEST;
1003 }
1004
1005 /* We need to create the radix trees late */
1006 static int irq_late_init(void)
1007 {
1008         struct irq_host *h;
1009         unsigned long flags;
1010
1011         irq_radix_wrlock(&flags);
1012         list_for_each_entry(h, &irq_hosts, link) {
1013                 if (h->revmap_type == IRQ_HOST_MAP_TREE)
1014                         INIT_RADIX_TREE(&h->revmap_data.tree, GFP_ATOMIC);
1015         }
1016         irq_radix_wrunlock(flags);
1017
1018         return 0;
1019 }
1020 arch_initcall(irq_late_init);
1021
1022 #ifdef CONFIG_VIRQ_DEBUG
1023 static int virq_debug_show(struct seq_file *m, void *private)
1024 {
1025         unsigned long flags;
1026         irq_desc_t *desc;
1027         const char *p;
1028         char none[] = "none";
1029         int i;
1030
1031         seq_printf(m, "%-5s  %-7s  %-15s  %s\n", "virq", "hwirq",
1032                       "chip name", "host name");
1033
1034         for (i = 1; i < NR_IRQS; i++) {
1035                 desc = get_irq_desc(i);
1036                 spin_lock_irqsave(&desc->lock, flags);
1037
1038                 if (desc->action && desc->action->handler) {
1039                         seq_printf(m, "%5d  ", i);
1040                         seq_printf(m, "0x%05lx  ", virq_to_hw(i));
1041
1042                         if (desc->chip && desc->chip->typename)
1043                                 p = desc->chip->typename;
1044                         else
1045                                 p = none;
1046                         seq_printf(m, "%-15s  ", p);
1047
1048                         if (irq_map[i].host && irq_map[i].host->of_node)
1049                                 p = irq_map[i].host->of_node->full_name;
1050                         else
1051                                 p = none;
1052                         seq_printf(m, "%s\n", p);
1053                 }
1054
1055                 spin_unlock_irqrestore(&desc->lock, flags);
1056         }
1057
1058         return 0;
1059 }
1060
1061 static int virq_debug_open(struct inode *inode, struct file *file)
1062 {
1063         return single_open(file, virq_debug_show, inode->i_private);
1064 }
1065
1066 static const struct file_operations virq_debug_fops = {
1067         .open = virq_debug_open,
1068         .read = seq_read,
1069         .llseek = seq_lseek,
1070         .release = single_release,
1071 };
1072
1073 static int __init irq_debugfs_init(void)
1074 {
1075         if (debugfs_create_file("virq_mapping", S_IRUGO, powerpc_debugfs_root,
1076                                  NULL, &virq_debug_fops) == NULL)
1077                 return -ENOMEM;
1078
1079         return 0;
1080 }
1081 __initcall(irq_debugfs_init);
1082 #endif /* CONFIG_VIRQ_DEBUG */
1083
1084 #endif /* CONFIG_PPC_MERGE */
1085
1086 #ifdef CONFIG_PPC64
1087 static int __init setup_noirqdistrib(char *str)
1088 {
1089         distribute_irqs = 0;
1090         return 1;
1091 }
1092
1093 __setup("noirqdistrib", setup_noirqdistrib);
1094 #endif /* CONFIG_PPC64 */