kernel/irq/chip.c

   1 /*
   2  * linux/kernel/irq/chip.c
   3  *
   4  * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar
   5  * Copyright (C) 2005-2006, Thomas Gleixner, Russell King
   6  *
   7  * This file contains the core interrupt handling code, for irq-chip
   8  * based architectures.
   9  *
  10  * Detailed information is available in Documentation/DocBook/genericirq
  11  */
  12
  13 #include <linux/irq.h>
  14 #include <linux/msi.h>
  15 #include <linux/module.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/kernel_stat.h>
  18
  19 #include <trace/events/irq.h>
  20
  21 #include "internals.h"
  22
  23 /**
  24  *      irq_set_chip - set the irq chip for an irq
  25  *      @irq:   irq number
  26  *      @chip:  pointer to irq chip description structure
  27  */
  28 int irq_set_chip(unsigned int irq, struct irq_chip *chip)
  29 {
  30         unsigned long flags;
  31         struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
  32
  33         if (!desc)
  34                 return -EINVAL;
  35
  36         if (!chip)
  37                 chip = &no_irq_chip;
  38
  39         desc->irq_data.chip = chip;
  40         irq_put_desc_unlock(desc, flags);
  41         /*
  42          * For !CONFIG_SPARSE_IRQ make the irq show up in
  43          * allocated_irqs.
  44          */
  45         irq_mark_irq(irq);
  46         return 0;
  47 }
  48 EXPORT_SYMBOL(irq_set_chip);
  49
  50 /**
  51  *      irq_set_type - set the irq trigger type for an irq
  52  *      @irq:   irq number
  53  *      @type:  IRQ_TYPE_{LEVEL,EDGE}_* value - see include/linux/irq.h
  54  */
  55 int irq_set_irq_type(unsigned int irq, unsigned int type)
  56 {
  57         unsigned long flags;
  58         struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
  59         int ret = 0;
  60
  61         if (!desc)
  62                 return -EINVAL;
  63
  64         type &= IRQ_TYPE_SENSE_MASK;
  65         ret = __irq_set_trigger(desc, irq, type);
  66         irq_put_desc_busunlock(desc, flags);
  67         return ret;
  68 }
  69 EXPORT_SYMBOL(irq_set_irq_type);
  70
  71 /**
  72  *      irq_set_handler_data - set irq handler data for an irq
  73  *      @irq:   Interrupt number
  74  *      @data:  Pointer to interrupt specific data
  75  *
  76  *      Set the hardware irq controller data for an irq
  77  */
  78 int irq_set_handler_data(unsigned int irq, void *data)
  79 {
  80         unsigned long flags;
  81         struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
  82
  83         if (!desc)
  84                 return -EINVAL;
  85         desc->irq_data.handler_data = data;
  86         irq_put_desc_unlock(desc, flags);
  87         return 0;
  88 }
  89 EXPORT_SYMBOL(irq_set_handler_data);
  90
  91 /**
  92  *      irq_set_msi_desc_off - set MSI descriptor data for an irq at offset
  93  *      @irq_base:      Interrupt number base
  94  *      @irq_offset:    Interrupt number offset
  95  *      @entry:         Pointer to MSI descriptor data
  96  *
  97  *      Set the MSI descriptor entry for an irq at offset
  98  */
  99 int irq_set_msi_desc_off(unsigned int irq_base, unsigned int irq_offset,
 100                          struct msi_desc *entry)
 101 {
 102         unsigned long flags;
 103         struct irq_desc *desc = irq_get_desc_lock(irq_base + irq_offset, &flags, IRQ_GET_DESC_CHECK_GLOBAL);
 104
 105         if (!desc)
 106                 return -EINVAL;
 107         desc->irq_data.msi_desc = entry;
 108         if (entry && !irq_offset)
 109                 entry->irq = irq_base;
 110         irq_put_desc_unlock(desc, flags);
 111         return 0;
 112 }
 113
 114 /**
 115  *      irq_set_msi_desc - set MSI descriptor data for an irq
 116  *      @irq:   Interrupt number
 117  *      @entry: Pointer to MSI descriptor data
 118  *
 119  *      Set the MSI descriptor entry for an irq
 120  */
 121 int irq_set_msi_desc(unsigned int irq, struct msi_desc *entry)
 122 {
 123         return irq_set_msi_desc_off(irq, 0, entry);
 124 }
 125
 126 /**
 127  *      irq_set_chip_data - set irq chip data for an irq
 128  *      @irq:   Interrupt number
 129  *      @data:  Pointer to chip specific data
 130  *
 131  *      Set the hardware irq chip data for an irq
 132  */
 133 int irq_set_chip_data(unsigned int irq, void *data)
 134 {
 135         unsigned long flags;
 136         struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
 137
 138         if (!desc)
 139                 return -EINVAL;
 140         desc->irq_data.chip_data = data;
 141         irq_put_desc_unlock(desc, flags);
 142         return 0;
 143 }
 144 EXPORT_SYMBOL(irq_set_chip_data);
 145
 146 struct irq_data *irq_get_irq_data(unsigned int irq)
 147 {
 148         struct irq_desc *desc = irq_to_desc(irq);
 149
 150         return desc ? &desc->irq_data : NULL;
 151 }
 152 EXPORT_SYMBOL_GPL(irq_get_irq_data);
 153
 154 static void irq_state_clr_disabled(struct irq_desc *desc)
 155 {
 156         irqd_clear(&desc->irq_data, IRQD_IRQ_DISABLED);
 157 }
 158
 159 static void irq_state_set_disabled(struct irq_desc *desc)
 160 {
 161         irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
 162 }
 163
 164 static void irq_state_clr_masked(struct irq_desc *desc)
 165 {
 166         irqd_clear(&desc->irq_data, IRQD_IRQ_MASKED);
 167 }
 168
 169 static void irq_state_set_masked(struct irq_desc *desc)
 170 {
 171         irqd_set(&desc->irq_data, IRQD_IRQ_MASKED);
 172 }
 173
 174 int irq_startup(struct irq_desc *desc, bool resend)
 175 {
 176         int ret = 0;
 177
 178         irq_state_clr_disabled(desc);
 179         desc->depth = 0;
 180
 181         if (desc->irq_data.chip->irq_startup) {
 182                 ret = desc->irq_data.chip->irq_startup(&desc->irq_data);
 183                 irq_state_clr_masked(desc);
 184         } else {
 185                 irq_enable(desc);
 186         }
 187         if (resend)
 188                 check_irq_resend(desc, desc->irq_data.irq);
 189         return ret;
 190 }
 191
 192 void irq_shutdown(struct irq_desc *desc)
 193 {
 194         irq_state_set_disabled(desc);
 195         desc->depth = 1;
 196         if (desc->irq_data.chip->irq_shutdown)
 197                 desc->irq_data.chip->irq_shutdown(&desc->irq_data);
 198         else if (desc->irq_data.chip->irq_disable)
 199                 desc->irq_data.chip->irq_disable(&desc->irq_data);
 200         else
 201                 desc->irq_data.chip->irq_mask(&desc->irq_data);
 202         irq_state_set_masked(desc);
 203 }
 204
 205 void irq_enable(struct irq_desc *desc)
 206 {
 207         irq_state_clr_disabled(desc);
 208         if (desc->irq_data.chip->irq_enable)
 209                 desc->irq_data.chip->irq_enable(&desc->irq_data);
 210         else
 211                 desc->irq_data.chip->irq_unmask(&desc->irq_data);
 212         irq_state_clr_masked(desc);
 213 }
 214
 215 /**
 216  * irq_disable - Mark interrupt disabled
 217  * @desc:       irq descriptor which should be disabled
 218  *
 219  * If the chip does not implement the irq_disable callback, we
 220  * use a lazy disable approach. That means we mark the interrupt
 221  * disabled, but leave the hardware unmasked. That's an
 222  * optimization because we avoid the hardware access for the
 223  * common case where no interrupt happens after we marked it
 224  * disabled. If an interrupt happens, then the interrupt flow
 225  * handler masks the line at the hardware level and marks it
 226  * pending.
 227  */
 228 void irq_disable(struct irq_desc *desc)
 229 {
 230         irq_state_set_disabled(desc);
 231         if (desc->irq_data.chip->irq_disable) {
 232                 desc->irq_data.chip->irq_disable(&desc->irq_data);
 233                 irq_state_set_masked(desc);
 234         }
 235 }
 236
 237 void irq_percpu_enable(struct irq_desc *desc, unsigned int cpu)
 238 {
 239         if (desc->irq_data.chip->irq_enable)
 240                 desc->irq_data.chip->irq_enable(&desc->irq_data);
 241         else
 242                 desc->irq_data.chip->irq_unmask(&desc->irq_data);
 243         cpumask_set_cpu(cpu, desc->percpu_enabled);
 244 }
 245
 246 void irq_percpu_disable(struct irq_desc *desc, unsigned int cpu)
 247 {
 248         if (desc->irq_data.chip->irq_disable)
 249                 desc->irq_data.chip->irq_disable(&desc->irq_data);
 250         else
 251                 desc->irq_data.chip->irq_mask(&desc->irq_data);
 252         cpumask_clear_cpu(cpu, desc->percpu_enabled);
 253 }
 254
 255 static inline void mask_ack_irq(struct irq_desc *desc)
 256 {
 257         if (desc->irq_data.chip->irq_mask_ack)
 258                 desc->irq_data.chip->irq_mask_ack(&desc->irq_data);
 259         else {
 260                 desc->irq_data.chip->irq_mask(&desc->irq_data);
 261                 if (desc->irq_data.chip->irq_ack)
 262                         desc->irq_data.chip->irq_ack(&desc->irq_data);
 263         }
 264         irq_state_set_masked(desc);
 265 }
 266
 267 void mask_irq(struct irq_desc *desc)
 268 {
 269         if (desc->irq_data.chip->irq_mask) {
 270                 desc->irq_data.chip->irq_mask(&desc->irq_data);
 271                 irq_state_set_masked(desc);
 272         }
 273 }
 274
 275 void unmask_irq(struct irq_desc *desc)
 276 {
 277         if (desc->irq_data.chip->irq_unmask) {
 278                 desc->irq_data.chip->irq_unmask(&desc->irq_data);
 279                 irq_state_clr_masked(desc);
 280         }
 281 }
 282
 283 void unmask_threaded_irq(struct irq_desc *desc)
 284 {
 285         struct irq_chip *chip = desc->irq_data.chip;
 286
 287         if (chip->flags & IRQCHIP_EOI_THREADED)
 288                 chip->irq_eoi(&desc->irq_data);
 289
 290         if (chip->irq_unmask) {
 291                 chip->irq_unmask(&desc->irq_data);
 292                 irq_state_clr_masked(desc);
 293         }
 294 }
 295
 296 /*
 297  *      handle_nested_irq - Handle a nested irq from a irq thread
 298  *      @irq:   the interrupt number
 299  *
 300  *      Handle interrupts which are nested into a threaded interrupt
 301  *      handler. The handler function is called inside the calling
 302  *      threads context.
 303  */
 304 void handle_nested_irq(unsigned int irq)
 305 {
 306         struct irq_desc *desc = irq_to_desc(irq);
 307         struct irqaction *action;
 308         irqreturn_t action_ret;
 309
 310         might_sleep();
 311
 312         raw_spin_lock_irq(&desc->lock);
 313
 314         desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
 315         kstat_incr_irqs_this_cpu(irq, desc);
 316
 317         action = desc->action;
 318         if (unlikely(!action || irqd_irq_disabled(&desc->irq_data))) {
 319                 desc->istate |= IRQS_PENDING;
 320                 goto out_unlock;
 321         }
 322
 323         irqd_set(&desc->irq_data, IRQD_IRQ_INPROGRESS);
 324         raw_spin_unlock_irq(&desc->lock);
 325
 326         action_ret = action->thread_fn(action->irq, action->dev_id);
 327         if (!noirqdebug)
 328                 note_interrupt(irq, desc, action_ret);
 329
 330         raw_spin_lock_irq(&desc->lock);
 331         irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS);
 332
 333 out_unlock:
 334         raw_spin_unlock_irq(&desc->lock);
 335 }
 336 EXPORT_SYMBOL_GPL(handle_nested_irq);
 337
 338 static bool irq_check_poll(struct irq_desc *desc)
 339 {
 340         if (!(desc->istate & IRQS_POLL_INPROGRESS))
 341                 return false;
 342         return irq_wait_for_poll(desc);
 343 }
 344
 345 static bool irq_may_run(struct irq_desc *desc)
 346 {
 347         if (!irqd_irq_inprogress(&desc->irq_data))
 348                 return true;
 349         return irq_check_poll(desc);
 350 }
 351
 352 /**
 353  *      handle_simple_irq - Simple and software-decoded IRQs.
 354  *      @irq:   the interrupt number
 355  *      @desc:  the interrupt description structure for this irq
 356  *
 357  *      Simple interrupts are either sent from a demultiplexing interrupt
 358  *      handler or come from hardware, where no interrupt hardware control
 359  *      is necessary.
 360  *
 361  *      Note: The caller is expected to handle the ack, clear, mask and
 362  *      unmask issues if necessary.
 363  */
 364 void
 365 handle_simple_irq(unsigned int irq, struct irq_desc *desc)
 366 {
 367         raw_spin_lock(&desc->lock);
 368
 369         if (!irq_may_run(desc))
 370                 goto out_unlock;
 371
 372         desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
 373         kstat_incr_irqs_this_cpu(irq, desc);
 374
 375         if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
 376                 desc->istate |= IRQS_PENDING;
 377                 goto out_unlock;
 378         }
 379
 380         handle_irq_event(desc);
 381
 382 out_unlock:
 383         raw_spin_unlock(&desc->lock);
 384 }
 385 EXPORT_SYMBOL_GPL(handle_simple_irq);
 386
 387 /*
 388  * Called unconditionally from handle_level_irq() and only for oneshot
 389  * interrupts from handle_fasteoi_irq()
 390  */
 391 static void cond_unmask_irq(struct irq_desc *desc)
 392 {
 393         /*
 394          * We need to unmask in the following cases:
 395          * - Standard level irq (IRQF_ONESHOT is not set)
 396          * - Oneshot irq which did not wake the thread (caused by a
 397          *   spurious interrupt or a primary handler handling it
 398          *   completely).
 399          */
 400         if (!irqd_irq_disabled(&desc->irq_data) &&
 401             irqd_irq_masked(&desc->irq_data) && !desc->threads_oneshot)
 402                 unmask_irq(desc);
 403 }
 404
 405 /**
 406  *      handle_level_irq - Level type irq handler
 407  *      @irq:   the interrupt number
 408  *      @desc:  the interrupt description structure for this irq
 409  *
 410  *      Level type interrupts are active as long as the hardware line has
 411  *      the active level. This may require to mask the interrupt and unmask
 412  *      it after the associated handler has acknowledged the device, so the
 413  *      interrupt line is back to inactive.
 414  */
 415 void
 416 handle_level_irq(unsigned int irq, struct irq_desc *desc)
 417 {
 418         raw_spin_lock(&desc->lock);
 419         mask_ack_irq(desc);
 420
 421         if (!irq_may_run(desc))
 422                 goto out_unlock;
 423
 424         desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
 425         kstat_incr_irqs_this_cpu(irq, desc);
 426
 427         /*
 428          * If its disabled or no action available
 429          * keep it masked and get out of here
 430          */
 431         if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
 432                 desc->istate |= IRQS_PENDING;
 433                 goto out_unlock;
 434         }
 435
 436         handle_irq_event(desc);
 437
 438         cond_unmask_irq(desc);
 439
 440 out_unlock:
 441         raw_spin_unlock(&desc->lock);
 442 }
 443 EXPORT_SYMBOL_GPL(handle_level_irq);
 444
 445 #ifdef CONFIG_IRQ_PREFLOW_FASTEOI
 446 static inline void preflow_handler(struct irq_desc *desc)
 447 {
 448         if (desc->preflow_handler)
 449                 desc->preflow_handler(&desc->irq_data);
 450 }
 451 #else
 452 static inline void preflow_handler(struct irq_desc *desc) { }
 453 #endif
 454
 455 static void cond_unmask_eoi_irq(struct irq_desc *desc, struct irq_chip *chip)
 456 {
 457         if (!(desc->istate & IRQS_ONESHOT)) {
 458                 chip->irq_eoi(&desc->irq_data);
 459                 return;
 460         }
 461         /*
 462          * We need to unmask in the following cases:
 463          * - Oneshot irq which did not wake the thread (caused by a
 464          *   spurious interrupt or a primary handler handling it
 465          *   completely).
 466          */
 467         if (!irqd_irq_disabled(&desc->irq_data) &&
 468             irqd_irq_masked(&desc->irq_data) && !desc->threads_oneshot) {
 469                 chip->irq_eoi(&desc->irq_data);
 470                 unmask_irq(desc);
 471         } else if (!(chip->flags & IRQCHIP_EOI_THREADED)) {
 472                 chip->irq_eoi(&desc->irq_data);
 473         }
 474 }
 475
 476 /**
 477  *      handle_fasteoi_irq - irq handler for transparent controllers
 478  *      @irq:   the interrupt number
 479  *      @desc:  the interrupt description structure for this irq
 480  *
 481  *      Only a single callback will be issued to the chip: an ->eoi()
 482  *      call when the interrupt has been serviced. This enables support
 483  *      for modern forms of interrupt handlers, which handle the flow
 484  *      details in hardware, transparently.
 485  */
 486 void
 487 handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc)
 488 {
 489         struct irq_chip *chip = desc->irq_data.chip;
 490
 491         raw_spin_lock(&desc->lock);
 492
 493         if (!irq_may_run(desc))
 494                 goto out;
 495
 496         desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
 497         kstat_incr_irqs_this_cpu(irq, desc);
 498
 499         /*
 500          * If its disabled or no action available
 501          * then mask it and get out of here:
 502          */
 503         if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
 504                 desc->istate |= IRQS_PENDING;
 505                 mask_irq(desc);
 506                 goto out;
 507         }
 508
 509         if (desc->istate & IRQS_ONESHOT)
 510                 mask_irq(desc);
 511
 512         preflow_handler(desc);
 513         handle_irq_event(desc);
 514
 515         cond_unmask_eoi_irq(desc, chip);
 516
 517         raw_spin_unlock(&desc->lock);
 518         return;
 519 out:
 520         if (!(chip->flags & IRQCHIP_EOI_IF_HANDLED))
 521                 chip->irq_eoi(&desc->irq_data);
 522         raw_spin_unlock(&desc->lock);
 523 }
 524
 525 /**
 526  *      handle_edge_irq - edge type IRQ handler
 527  *      @irq:   the interrupt number
 528  *      @desc:  the interrupt description structure for this irq
 529  *
 530  *      Interrupt occures on the falling and/or rising edge of a hardware
 531  *      signal. The occurrence is latched into the irq controller hardware
 532  *      and must be acked in order to be reenabled. After the ack another
 533  *      interrupt can happen on the same source even before the first one
 534  *      is handled by the associated event handler. If this happens it
 535  *      might be necessary to disable (mask) the interrupt depending on the
 536  *      controller hardware. This requires to reenable the interrupt inside
 537  *      of the loop which handles the interrupts which have arrived while
 538  *      the handler was running. If all pending interrupts are handled, the
 539  *      loop is left.
 540  */
 541 void
 542 handle_edge_irq(unsigned int irq, struct irq_desc *desc)
 543 {
 544         raw_spin_lock(&desc->lock);
 545
 546         desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
 547
 548         if (!irq_may_run(desc)) {
 549                 desc->istate |= IRQS_PENDING;
 550                 mask_ack_irq(desc);
 551                 goto out_unlock;
 552         }
 553
 554         /*
 555          * If its disabled or no action available then mask it and get
 556          * out of here.
 557          */
 558         if (irqd_irq_disabled(&desc->irq_data) || !desc->action) {
 559                 desc->istate |= IRQS_PENDING;
 560                 mask_ack_irq(desc);
 561                 goto out_unlock;
 562         }
 563
 564         kstat_incr_irqs_this_cpu(irq, desc);
 565
 566         /* Start handling the irq */
 567         desc->irq_data.chip->irq_ack(&desc->irq_data);
 568
 569         do {
 570                 if (unlikely(!desc->action)) {
 571                         mask_irq(desc);
 572                         goto out_unlock;
 573                 }
 574
 575                 /*
 576                  * When another irq arrived while we were handling
 577                  * one, we could have masked the irq.
 578                  * Renable it, if it was not disabled in meantime.
 579                  */
 580                 if (unlikely(desc->istate & IRQS_PENDING)) {
 581                         if (!irqd_irq_disabled(&desc->irq_data) &&
 582                             irqd_irq_masked(&desc->irq_data))
 583                                 unmask_irq(desc);
 584                 }
 585
 586                 handle_irq_event(desc);
 587
 588         } while ((desc->istate & IRQS_PENDING) &&
 589                  !irqd_irq_disabled(&desc->irq_data));
 590
 591 out_unlock:
 592         raw_spin_unlock(&desc->lock);
 593 }
 594 EXPORT_SYMBOL(handle_edge_irq);
 595
 596 #ifdef CONFIG_IRQ_EDGE_EOI_HANDLER
 597 /**
 598  *      handle_edge_eoi_irq - edge eoi type IRQ handler
 599  *      @irq:   the interrupt number
 600  *      @desc:  the interrupt description structure for this irq
 601  *
 602  * Similar as the above handle_edge_irq, but using eoi and w/o the
 603  * mask/unmask logic.
 604  */
 605 void handle_edge_eoi_irq(unsigned int irq, struct irq_desc *desc)
 606 {
 607         struct irq_chip *chip = irq_desc_get_chip(desc);
 608
 609         raw_spin_lock(&desc->lock);
 610
 611         desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
 612
 613         if (!irq_may_run(desc)) {
 614                 desc->istate |= IRQS_PENDING;
 615                 goto out_eoi;
 616         }
 617
 618         /*
 619          * If its disabled or no action available then mask it and get
 620          * out of here.
 621          */
 622         if (irqd_irq_disabled(&desc->irq_data) || !desc->action) {
 623                 desc->istate |= IRQS_PENDING;
 624                 goto out_eoi;
 625         }
 626
 627         kstat_incr_irqs_this_cpu(irq, desc);
 628
 629         do {
 630                 if (unlikely(!desc->action))
 631                         goto out_eoi;
 632
 633                 handle_irq_event(desc);
 634
 635         } while ((desc->istate & IRQS_PENDING) &&
 636                  !irqd_irq_disabled(&desc->irq_data));
 637
 638 out_eoi:
 639         chip->irq_eoi(&desc->irq_data);
 640         raw_spin_unlock(&desc->lock);
 641 }
 642 #endif
 643
 644 /**
 645  *      handle_percpu_irq - Per CPU local irq handler
 646  *      @irq:   the interrupt number
 647  *      @desc:  the interrupt description structure for this irq
 648  *
 649  *      Per CPU interrupts on SMP machines without locking requirements
 650  */
 651 void
 652 handle_percpu_irq(unsigned int irq, struct irq_desc *desc)
 653 {
 654         struct irq_chip *chip = irq_desc_get_chip(desc);
 655
 656         kstat_incr_irqs_this_cpu(irq, desc);
 657
 658         if (chip->irq_ack)
 659                 chip->irq_ack(&desc->irq_data);
 660
 661         handle_irq_event_percpu(desc, desc->action);
 662
 663         if (chip->irq_eoi)
 664                 chip->irq_eoi(&desc->irq_data);
 665 }
 666
 667 /**
 668  * handle_percpu_devid_irq - Per CPU local irq handler with per cpu dev ids
 669  * @irq:        the interrupt number
 670  * @desc:       the interrupt description structure for this irq
 671  *
 672  * Per CPU interrupts on SMP machines without locking requirements. Same as
 673  * handle_percpu_irq() above but with the following extras:
 674  *
 675  * action->percpu_dev_id is a pointer to percpu variables which
 676  * contain the real device id for the cpu on which this handler is
 677  * called
 678  */
 679 void handle_percpu_devid_irq(unsigned int irq, struct irq_desc *desc)
 680 {
 681         struct irq_chip *chip = irq_desc_get_chip(desc);
 682         struct irqaction *action = desc->action;
 683         void *dev_id = __this_cpu_ptr(action->percpu_dev_id);
 684         irqreturn_t res;
 685
 686         kstat_incr_irqs_this_cpu(irq, desc);
 687
 688         if (chip->irq_ack)
 689                 chip->irq_ack(&desc->irq_data);
 690
 691         trace_irq_handler_entry(irq, action);
 692         res = action->handler(irq, dev_id);
 693         trace_irq_handler_exit(irq, action, res);
 694
 695         if (chip->irq_eoi)
 696                 chip->irq_eoi(&desc->irq_data);
 697 }
 698
 699 void
 700 __irq_set_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
 701                   const char *name)
 702 {
 703         unsigned long flags;
 704         struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, 0);
 705
 706         if (!desc)
 707                 return;
 708
 709         if (!handle) {
 710                 handle = handle_bad_irq;
 711         } else {
 712                 if (WARN_ON(desc->irq_data.chip == &no_irq_chip))
 713                         goto out;
 714         }
 715
 716         /* Uninstall? */
 717         if (handle == handle_bad_irq) {
 718                 if (desc->irq_data.chip != &no_irq_chip)
 719                         mask_ack_irq(desc);
 720                 irq_state_set_disabled(desc);
 721                 desc->depth = 1;
 722         }
 723         desc->handle_irq = handle;
 724         desc->name = name;
 725
 726         if (handle != handle_bad_irq && is_chained) {
 727                 irq_settings_set_noprobe(desc);
 728                 irq_settings_set_norequest(desc);
 729                 irq_settings_set_nothread(desc);
 730                 irq_startup(desc, true);
 731         }
 732 out:
 733         irq_put_desc_busunlock(desc, flags);
 734 }
 735 EXPORT_SYMBOL_GPL(__irq_set_handler);
 736
 737 void
 738 irq_set_chip_and_handler_name(unsigned int irq, struct irq_chip *chip,
 739                               irq_flow_handler_t handle, const char *name)
 740 {
 741         irq_set_chip(irq, chip);
 742         __irq_set_handler(irq, handle, 0, name);
 743 }
 744 EXPORT_SYMBOL_GPL(irq_set_chip_and_handler_name);
 745
 746 void irq_modify_status(unsigned int irq, unsigned long clr, unsigned long set)
 747 {
 748         unsigned long flags;
 749         struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
 750
 751         if (!desc)
 752                 return;
 753         irq_settings_clr_and_set(desc, clr, set);
 754
 755         irqd_clear(&desc->irq_data, IRQD_NO_BALANCING | IRQD_PER_CPU |
 756                    IRQD_TRIGGER_MASK | IRQD_LEVEL | IRQD_MOVE_PCNTXT);
 757         if (irq_settings_has_no_balance_set(desc))
 758                 irqd_set(&desc->irq_data, IRQD_NO_BALANCING);
 759         if (irq_settings_is_per_cpu(desc))
 760                 irqd_set(&desc->irq_data, IRQD_PER_CPU);
 761         if (irq_settings_can_move_pcntxt(desc))
 762                 irqd_set(&desc->irq_data, IRQD_MOVE_PCNTXT);
 763         if (irq_settings_is_level(desc))
 764                 irqd_set(&desc->irq_data, IRQD_LEVEL);
 765
 766         irqd_set(&desc->irq_data, irq_settings_get_trigger_mask(desc));
 767
 768         irq_put_desc_unlock(desc, flags);
 769 }
 770 EXPORT_SYMBOL_GPL(irq_modify_status);
 771
 772 /**
 773  *      irq_cpu_online - Invoke all irq_cpu_online functions.
 774  *
 775  *      Iterate through all irqs and invoke the chip.irq_cpu_online()
 776  *      for each.
 777  */
 778 void irq_cpu_online(void)
 779 {
 780         struct irq_desc *desc;
 781         struct irq_chip *chip;
 782         unsigned long flags;
 783         unsigned int irq;
 784
 785         for_each_active_irq(irq) {
 786                 desc = irq_to_desc(irq);
 787                 if (!desc)
 788                         continue;
 789
 790                 raw_spin_lock_irqsave(&desc->lock, flags);
 791
 792                 chip = irq_data_get_irq_chip(&desc->irq_data);
 793                 if (chip && chip->irq_cpu_online &&
 794                     (!(chip->flags & IRQCHIP_ONOFFLINE_ENABLED) ||
 795                      !irqd_irq_disabled(&desc->irq_data)))
 796                         chip->irq_cpu_online(&desc->irq_data);
 797
 798                 raw_spin_unlock_irqrestore(&desc->lock, flags);
 799         }
 800 }
 801
 802 /**
 803  *      irq_cpu_offline - Invoke all irq_cpu_offline functions.
 804  *
 805  *      Iterate through all irqs and invoke the chip.irq_cpu_offline()
 806  *      for each.
 807  */
 808 void irq_cpu_offline(void)
 809 {
 810         struct irq_desc *desc;
 811         struct irq_chip *chip;
 812         unsigned long flags;
 813         unsigned int irq;
 814
 815         for_each_active_irq(irq) {
 816                 desc = irq_to_desc(irq);
 817                 if (!desc)
 818                         continue;
 819
 820                 raw_spin_lock_irqsave(&desc->lock, flags);
 821
 822                 chip = irq_data_get_irq_chip(&desc->irq_data);
 823                 if (chip && chip->irq_cpu_offline &&
 824                     (!(chip->flags & IRQCHIP_ONOFFLINE_ENABLED) ||
 825                      !irqd_irq_disabled(&desc->irq_data)))
 826                         chip->irq_cpu_offline(&desc->irq_data);
 827
 828                 raw_spin_unlock_irqrestore(&desc->lock, flags);
 829         }
 830 }