kernel/irq/generic-chip.c

   1 /*
   2  * Library implementing the most common irq chip callback functions
   3  *
   4  * Copyright (C) 2011, Thomas Gleixner
   5  */
   6 #include <linux/io.h>
   7 #include <linux/irq.h>
   8 #include <linux/slab.h>
   9 #include <linux/export.h>
  10 #include <linux/irqdomain.h>
  11 #include <linux/interrupt.h>
  12 #include <linux/kernel_stat.h>
  13 #include <linux/syscore_ops.h>
  14
  15 #include "internals.h"
  16
  17 static LIST_HEAD(gc_list);
  18 static DEFINE_RAW_SPINLOCK(gc_lock);
  19
  20 /**
  21  * irq_gc_noop - NOOP function
  22  * @d: irq_data
  23  */
  24 void irq_gc_noop(struct irq_data *d)
  25 {
  26 }
  27
  28 /**
  29  * irq_gc_mask_disable_reg - Mask chip via disable register
  30  * @d: irq_data
  31  *
  32  * Chip has separate enable/disable registers instead of a single mask
  33  * register.
  34  */
  35 void irq_gc_mask_disable_reg(struct irq_data *d)
  36 {
  37         struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
  38         struct irq_chip_type *ct = irq_data_get_chip_type(d);
  39         u32 mask = d->mask;
  40
  41         irq_gc_lock(gc);
  42         irq_reg_writel(gc, mask, ct->regs.disable);
  43         *ct->mask_cache &= ~mask;
  44         irq_gc_unlock(gc);
  45 }
  46
  47 /**
  48  * irq_gc_mask_set_bit - Mask chip via setting bit in mask register
  49  * @d: irq_data
  50  *
  51  * Chip has a single mask register. Values of this register are cached
  52  * and protected by gc->lock
  53  */
  54 void irq_gc_mask_set_bit(struct irq_data *d)
  55 {
  56         struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
  57         struct irq_chip_type *ct = irq_data_get_chip_type(d);
  58         u32 mask = d->mask;
  59
  60         irq_gc_lock(gc);
  61         *ct->mask_cache |= mask;
  62         irq_reg_writel(gc, *ct->mask_cache, ct->regs.mask);
  63         irq_gc_unlock(gc);
  64 }
  65 EXPORT_SYMBOL_GPL(irq_gc_mask_set_bit);
  66
  67 /**
  68  * irq_gc_mask_clr_bit - Mask chip via clearing bit in mask register
  69  * @d: irq_data
  70  *
  71  * Chip has a single mask register. Values of this register are cached
  72  * and protected by gc->lock
  73  */
  74 void irq_gc_mask_clr_bit(struct irq_data *d)
  75 {
  76         struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
  77         struct irq_chip_type *ct = irq_data_get_chip_type(d);
  78         u32 mask = d->mask;
  79
  80         irq_gc_lock(gc);
  81         *ct->mask_cache &= ~mask;
  82         irq_reg_writel(gc, *ct->mask_cache, ct->regs.mask);
  83         irq_gc_unlock(gc);
  84 }
  85 EXPORT_SYMBOL_GPL(irq_gc_mask_clr_bit);
  86
  87 /**
  88  * irq_gc_unmask_enable_reg - Unmask chip via enable register
  89  * @d: irq_data
  90  *
  91  * Chip has separate enable/disable registers instead of a single mask
  92  * register.
  93  */
  94 void irq_gc_unmask_enable_reg(struct irq_data *d)
  95 {
  96         struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
  97         struct irq_chip_type *ct = irq_data_get_chip_type(d);
  98         u32 mask = d->mask;
  99
 100         irq_gc_lock(gc);
 101         irq_reg_writel(gc, mask, ct->regs.enable);
 102         *ct->mask_cache |= mask;
 103         irq_gc_unlock(gc);
 104 }
 105
 106 /**
 107  * irq_gc_ack_set_bit - Ack pending interrupt via setting bit
 108  * @d: irq_data
 109  */
 110 void irq_gc_ack_set_bit(struct irq_data *d)
 111 {
 112         struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
 113         struct irq_chip_type *ct = irq_data_get_chip_type(d);
 114         u32 mask = d->mask;
 115
 116         irq_gc_lock(gc);
 117         irq_reg_writel(gc, mask, ct->regs.ack);
 118         irq_gc_unlock(gc);
 119 }
 120 EXPORT_SYMBOL_GPL(irq_gc_ack_set_bit);
 121
 122 /**
 123  * irq_gc_ack_clr_bit - Ack pending interrupt via clearing bit
 124  * @d: irq_data
 125  */
 126 void irq_gc_ack_clr_bit(struct irq_data *d)
 127 {
 128         struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
 129         struct irq_chip_type *ct = irq_data_get_chip_type(d);
 130         u32 mask = ~d->mask;
 131
 132         irq_gc_lock(gc);
 133         irq_reg_writel(gc, mask, ct->regs.ack);
 134         irq_gc_unlock(gc);
 135 }
 136
 137 /**
 138  * irq_gc_mask_disable_reg_and_ack - Mask and ack pending interrupt
 139  * @d: irq_data
 140  */
 141 void irq_gc_mask_disable_reg_and_ack(struct irq_data *d)
 142 {
 143         struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
 144         struct irq_chip_type *ct = irq_data_get_chip_type(d);
 145         u32 mask = d->mask;
 146
 147         irq_gc_lock(gc);
 148         irq_reg_writel(gc, mask, ct->regs.mask);
 149         irq_reg_writel(gc, mask, ct->regs.ack);
 150         irq_gc_unlock(gc);
 151 }
 152
 153 /**
 154  * irq_gc_eoi - EOI interrupt
 155  * @d: irq_data
 156  */
 157 void irq_gc_eoi(struct irq_data *d)
 158 {
 159         struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
 160         struct irq_chip_type *ct = irq_data_get_chip_type(d);
 161         u32 mask = d->mask;
 162
 163         irq_gc_lock(gc);
 164         irq_reg_writel(gc, mask, ct->regs.eoi);
 165         irq_gc_unlock(gc);
 166 }
 167
 168 /**
 169  * irq_gc_set_wake - Set/clr wake bit for an interrupt
 170  * @d:  irq_data
 171  * @on: Indicates whether the wake bit should be set or cleared
 172  *
 173  * For chips where the wake from suspend functionality is not
 174  * configured in a separate register and the wakeup active state is
 175  * just stored in a bitmask.
 176  */
 177 int irq_gc_set_wake(struct irq_data *d, unsigned int on)
 178 {
 179         struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
 180         u32 mask = d->mask;
 181
 182         if (!(mask & gc->wake_enabled))
 183                 return -EINVAL;
 184
 185         irq_gc_lock(gc);
 186         if (on)
 187                 gc->wake_active |= mask;
 188         else
 189                 gc->wake_active &= ~mask;
 190         irq_gc_unlock(gc);
 191         return 0;
 192 }
 193
 194 static u32 irq_readl_be(void __iomem *addr)
 195 {
 196         return ioread32be(addr);
 197 }
 198
 199 static void irq_writel_be(u32 val, void __iomem *addr)
 200 {
 201         iowrite32be(val, addr);
 202 }
 203
 204 static void
 205 irq_init_generic_chip(struct irq_chip_generic *gc, const char *name,
 206                       int num_ct, unsigned int irq_base,
 207                       void __iomem *reg_base, irq_flow_handler_t handler)
 208 {
 209         raw_spin_lock_init(&gc->lock);
 210         gc->num_ct = num_ct;
 211         gc->irq_base = irq_base;
 212         gc->reg_base = reg_base;
 213         gc->chip_types->chip.name = name;
 214         gc->chip_types->handler = handler;
 215 }
 216
 217 /**
 218  * irq_alloc_generic_chip - Allocate a generic chip and initialize it
 219  * @name:       Name of the irq chip
 220  * @num_ct:     Number of irq_chip_type instances associated with this
 221  * @irq_base:   Interrupt base nr for this chip
 222  * @reg_base:   Register base address (virtual)
 223  * @handler:    Default flow handler associated with this chip
 224  *
 225  * Returns an initialized irq_chip_generic structure. The chip defaults
 226  * to the primary (index 0) irq_chip_type and @handler
 227  */
 228 struct irq_chip_generic *
 229 irq_alloc_generic_chip(const char *name, int num_ct, unsigned int irq_base,
 230                        void __iomem *reg_base, irq_flow_handler_t handler)
 231 {
 232         struct irq_chip_generic *gc;
 233         unsigned long sz = sizeof(*gc) + num_ct * sizeof(struct irq_chip_type);
 234
 235         gc = kzalloc(sz, GFP_KERNEL);
 236         if (gc) {
 237                 irq_init_generic_chip(gc, name, num_ct, irq_base, reg_base,
 238                                       handler);
 239         }
 240         return gc;
 241 }
 242 EXPORT_SYMBOL_GPL(irq_alloc_generic_chip);
 243
 244 static void
 245 irq_gc_init_mask_cache(struct irq_chip_generic *gc, enum irq_gc_flags flags)
 246 {
 247         struct irq_chip_type *ct = gc->chip_types;
 248         u32 *mskptr = &gc->mask_cache, mskreg = ct->regs.mask;
 249         int i;
 250
 251         for (i = 0; i < gc->num_ct; i++) {
 252                 if (flags & IRQ_GC_MASK_CACHE_PER_TYPE) {
 253                         mskptr = &ct[i].mask_cache_priv;
 254                         mskreg = ct[i].regs.mask;
 255                 }
 256                 ct[i].mask_cache = mskptr;
 257                 if (flags & IRQ_GC_INIT_MASK_CACHE)
 258                         *mskptr = irq_reg_readl(gc, mskreg);
 259         }
 260 }
 261
 262 /**
 263  * irq_alloc_domain_generic_chip - Allocate generic chips for an irq domain
 264  * @d:                  irq domain for which to allocate chips
 265  * @irqs_per_chip:      Number of interrupts each chip handles
 266  * @num_ct:             Number of irq_chip_type instances associated with this
 267  * @name:               Name of the irq chip
 268  * @handler:            Default flow handler associated with these chips
 269  * @clr:                IRQ_* bits to clear in the mapping function
 270  * @set:                IRQ_* bits to set in the mapping function
 271  * @gcflags:            Generic chip specific setup flags
 272  */
 273 int irq_alloc_domain_generic_chips(struct irq_domain *d, int irqs_per_chip,
 274                                    int num_ct, const char *name,
 275                                    irq_flow_handler_t handler,
 276                                    unsigned int clr, unsigned int set,
 277                                    enum irq_gc_flags gcflags)
 278 {
 279         struct irq_domain_chip_generic *dgc;
 280         struct irq_chip_generic *gc;
 281         int numchips, sz, i;
 282         unsigned long flags;
 283         void *tmp;
 284
 285         if (d->gc)
 286                 return -EBUSY;
 287
 288         numchips = DIV_ROUND_UP(d->revmap_size, irqs_per_chip);
 289         if (!numchips)
 290                 return -EINVAL;
 291
 292         /* Allocate a pointer, generic chip and chiptypes for each chip */
 293         sz = sizeof(*dgc) + numchips * sizeof(gc);
 294         sz += numchips * (sizeof(*gc) + num_ct * sizeof(struct irq_chip_type));
 295
 296         tmp = dgc = kzalloc(sz, GFP_KERNEL);
 297         if (!dgc)
 298                 return -ENOMEM;
 299         dgc->irqs_per_chip = irqs_per_chip;
 300         dgc->num_chips = numchips;
 301         dgc->irq_flags_to_set = set;
 302         dgc->irq_flags_to_clear = clr;
 303         dgc->gc_flags = gcflags;
 304         d->gc = dgc;
 305
 306         /* Calc pointer to the first generic chip */
 307         tmp += sizeof(*dgc) + numchips * sizeof(gc);
 308         for (i = 0; i < numchips; i++) {
 309                 /* Store the pointer to the generic chip */
 310                 dgc->gc[i] = gc = tmp;
 311                 irq_init_generic_chip(gc, name, num_ct, i * irqs_per_chip,
 312                                       NULL, handler);
 313
 314                 gc->domain = d;
 315                 if (gcflags & IRQ_GC_BE_IO) {
 316                         gc->reg_readl = &irq_readl_be;
 317                         gc->reg_writel = &irq_writel_be;
 318                 }
 319
 320                 raw_spin_lock_irqsave(&gc_lock, flags);
 321                 list_add_tail(&gc->list, &gc_list);
 322                 raw_spin_unlock_irqrestore(&gc_lock, flags);
 323                 /* Calc pointer to the next generic chip */
 324                 tmp += sizeof(*gc) + num_ct * sizeof(struct irq_chip_type);
 325         }
 326         d->name = name;
 327         return 0;
 328 }
 329 EXPORT_SYMBOL_GPL(irq_alloc_domain_generic_chips);
 330
 331 /**
 332  * irq_get_domain_generic_chip - Get a pointer to the generic chip of a hw_irq
 333  * @d:                  irq domain pointer
 334  * @hw_irq:             Hardware interrupt number
 335  */
 336 struct irq_chip_generic *
 337 irq_get_domain_generic_chip(struct irq_domain *d, unsigned int hw_irq)
 338 {
 339         struct irq_domain_chip_generic *dgc = d->gc;
 340         int idx;
 341
 342         if (!dgc)
 343                 return NULL;
 344         idx = hw_irq / dgc->irqs_per_chip;
 345         if (idx >= dgc->num_chips)
 346                 return NULL;
 347         return dgc->gc[idx];
 348 }
 349 EXPORT_SYMBOL_GPL(irq_get_domain_generic_chip);
 350
 351 /*
 352  * Separate lockdep class for interrupt chip which can nest irq_desc
 353  * lock.
 354  */
 355 static struct lock_class_key irq_nested_lock_class;
 356
 357 /*
 358  * irq_map_generic_chip - Map a generic chip for an irq domain
 359  */
 360 int irq_map_generic_chip(struct irq_domain *d, unsigned int virq,
 361                          irq_hw_number_t hw_irq)
 362 {
 363         struct irq_data *data = irq_domain_get_irq_data(d, virq);
 364         struct irq_domain_chip_generic *dgc = d->gc;
 365         struct irq_chip_generic *gc;
 366         struct irq_chip_type *ct;
 367         struct irq_chip *chip;
 368         unsigned long flags;
 369         int idx;
 370
 371         if (!d->gc)
 372                 return -ENODEV;
 373
 374         idx = hw_irq / dgc->irqs_per_chip;
 375         if (idx >= dgc->num_chips)
 376                 return -EINVAL;
 377         gc = dgc->gc[idx];
 378
 379         idx = hw_irq % dgc->irqs_per_chip;
 380
 381         if (test_bit(idx, &gc->unused))
 382                 return -ENOTSUPP;
 383
 384         if (test_bit(idx, &gc->installed))
 385                 return -EBUSY;
 386
 387         ct = gc->chip_types;
 388         chip = &ct->chip;
 389
 390         /* We only init the cache for the first mapping of a generic chip */
 391         if (!gc->installed) {
 392                 raw_spin_lock_irqsave(&gc->lock, flags);
 393                 irq_gc_init_mask_cache(gc, dgc->gc_flags);
 394                 raw_spin_unlock_irqrestore(&gc->lock, flags);
 395         }
 396
 397         /* Mark the interrupt as installed */
 398         set_bit(idx, &gc->installed);
 399
 400         if (dgc->gc_flags & IRQ_GC_INIT_NESTED_LOCK)
 401                 irq_set_lockdep_class(virq, &irq_nested_lock_class);
 402
 403         if (chip->irq_calc_mask)
 404                 chip->irq_calc_mask(data);
 405         else
 406                 data->mask = 1 << idx;
 407
 408         irq_domain_set_info(d, virq, hw_irq, chip, gc, ct->handler, NULL, NULL);
 409         irq_modify_status(virq, dgc->irq_flags_to_clear, dgc->irq_flags_to_set);
 410         return 0;
 411 }
 412 EXPORT_SYMBOL_GPL(irq_map_generic_chip);
 413
 414 struct irq_domain_ops irq_generic_chip_ops = {
 415         .map    = irq_map_generic_chip,
 416         .xlate  = irq_domain_xlate_onetwocell,
 417 };
 418 EXPORT_SYMBOL_GPL(irq_generic_chip_ops);
 419
 420 /**
 421  * irq_setup_generic_chip - Setup a range of interrupts with a generic chip
 422  * @gc:         Generic irq chip holding all data
 423  * @msk:        Bitmask holding the irqs to initialize relative to gc->irq_base
 424  * @flags:      Flags for initialization
 425  * @clr:        IRQ_* bits to clear
 426  * @set:        IRQ_* bits to set
 427  *
 428  * Set up max. 32 interrupts starting from gc->irq_base. Note, this
 429  * initializes all interrupts to the primary irq_chip_type and its
 430  * associated handler.
 431  */
 432 void irq_setup_generic_chip(struct irq_chip_generic *gc, u32 msk,
 433                             enum irq_gc_flags flags, unsigned int clr,
 434                             unsigned int set)
 435 {
 436         struct irq_chip_type *ct = gc->chip_types;
 437         struct irq_chip *chip = &ct->chip;
 438         unsigned int i;
 439
 440         raw_spin_lock(&gc_lock);
 441         list_add_tail(&gc->list, &gc_list);
 442         raw_spin_unlock(&gc_lock);
 443
 444         irq_gc_init_mask_cache(gc, flags);
 445
 446         for (i = gc->irq_base; msk; msk >>= 1, i++) {
 447                 if (!(msk & 0x01))
 448                         continue;
 449
 450                 if (flags & IRQ_GC_INIT_NESTED_LOCK)
 451                         irq_set_lockdep_class(i, &irq_nested_lock_class);
 452
 453                 if (!(flags & IRQ_GC_NO_MASK)) {
 454                         struct irq_data *d = irq_get_irq_data(i);
 455
 456                         if (chip->irq_calc_mask)
 457                                 chip->irq_calc_mask(d);
 458                         else
 459                                 d->mask = 1 << (i - gc->irq_base);
 460                 }
 461                 irq_set_chip_and_handler(i, chip, ct->handler);
 462                 irq_set_chip_data(i, gc);
 463                 irq_modify_status(i, clr, set);
 464         }
 465         gc->irq_cnt = i - gc->irq_base;
 466 }
 467 EXPORT_SYMBOL_GPL(irq_setup_generic_chip);
 468
 469 /**
 470  * irq_setup_alt_chip - Switch to alternative chip
 471  * @d:          irq_data for this interrupt
 472  * @type:       Flow type to be initialized
 473  *
 474  * Only to be called from chip->irq_set_type() callbacks.
 475  */
 476 int irq_setup_alt_chip(struct irq_data *d, unsigned int type)
 477 {
 478         struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
 479         struct irq_chip_type *ct = gc->chip_types;
 480         unsigned int i;
 481
 482         for (i = 0; i < gc->num_ct; i++, ct++) {
 483                 if (ct->type & type) {
 484                         d->chip = &ct->chip;
 485                         irq_data_to_desc(d)->handle_irq = ct->handler;
 486                         return 0;
 487                 }
 488         }
 489         return -EINVAL;
 490 }
 491 EXPORT_SYMBOL_GPL(irq_setup_alt_chip);
 492
 493 /**
 494  * irq_remove_generic_chip - Remove a chip
 495  * @gc:         Generic irq chip holding all data
 496  * @msk:        Bitmask holding the irqs to initialize relative to gc->irq_base
 497  * @clr:        IRQ_* bits to clear
 498  * @set:        IRQ_* bits to set
 499  *
 500  * Remove up to 32 interrupts starting from gc->irq_base.
 501  */
 502 void irq_remove_generic_chip(struct irq_chip_generic *gc, u32 msk,
 503                              unsigned int clr, unsigned int set)
 504 {
 505         unsigned int i = gc->irq_base;
 506
 507         raw_spin_lock(&gc_lock);
 508         list_del(&gc->list);
 509         raw_spin_unlock(&gc_lock);
 510
 511         for (; msk; msk >>= 1, i++) {
 512                 if (!(msk & 0x01))
 513                         continue;
 514
 515                 /* Remove handler first. That will mask the irq line */
 516                 irq_set_handler(i, NULL);
 517                 irq_set_chip(i, &no_irq_chip);
 518                 irq_set_chip_data(i, NULL);
 519                 irq_modify_status(i, clr, set);
 520         }
 521 }
 522 EXPORT_SYMBOL_GPL(irq_remove_generic_chip);
 523
 524 static struct irq_data *irq_gc_get_irq_data(struct irq_chip_generic *gc)
 525 {
 526         unsigned int virq;
 527
 528         if (!gc->domain)
 529                 return irq_get_irq_data(gc->irq_base);
 530
 531         /*
 532          * We don't know which of the irqs has been actually
 533          * installed. Use the first one.
 534          */
 535         if (!gc->installed)
 536                 return NULL;
 537
 538         virq = irq_find_mapping(gc->domain, gc->irq_base + __ffs(gc->installed));
 539         return virq ? irq_get_irq_data(virq) : NULL;
 540 }
 541
 542 #ifdef CONFIG_PM
 543 static int irq_gc_suspend(void)
 544 {
 545         struct irq_chip_generic *gc;
 546
 547         list_for_each_entry(gc, &gc_list, list) {
 548                 struct irq_chip_type *ct = gc->chip_types;
 549
 550                 if (ct->chip.irq_suspend) {
 551                         struct irq_data *data = irq_gc_get_irq_data(gc);
 552
 553                         if (data)
 554                                 ct->chip.irq_suspend(data);
 555                 }
 556
 557                 if (gc->suspend)
 558                         gc->suspend(gc);
 559         }
 560         return 0;
 561 }
 562
 563 static void irq_gc_resume(void)
 564 {
 565         struct irq_chip_generic *gc;
 566
 567         list_for_each_entry(gc, &gc_list, list) {
 568                 struct irq_chip_type *ct = gc->chip_types;
 569
 570                 if (gc->resume)
 571                         gc->resume(gc);
 572
 573                 if (ct->chip.irq_resume) {
 574                         struct irq_data *data = irq_gc_get_irq_data(gc);
 575
 576                         if (data)
 577                                 ct->chip.irq_resume(data);
 578                 }
 579         }
 580 }
 581 #else
 582 #define irq_gc_suspend NULL
 583 #define irq_gc_resume NULL
 584 #endif
 585
 586 static void irq_gc_shutdown(void)
 587 {
 588         struct irq_chip_generic *gc;
 589
 590         list_for_each_entry(gc, &gc_list, list) {
 591                 struct irq_chip_type *ct = gc->chip_types;
 592
 593                 if (ct->chip.irq_pm_shutdown) {
 594                         struct irq_data *data = irq_gc_get_irq_data(gc);
 595
 596                         if (data)
 597                                 ct->chip.irq_pm_shutdown(data);
 598                 }
 599         }
 600 }
 601
 602 static struct syscore_ops irq_gc_syscore_ops = {
 603         .suspend = irq_gc_suspend,
 604         .resume = irq_gc_resume,
 605         .shutdown = irq_gc_shutdown,
 606 };
 607
 608 static int __init irq_gc_init_ops(void)
 609 {
 610         register_syscore_ops(&irq_gc_syscore_ops);
 611         return 0;
 612 }
 613 device_initcall(irq_gc_init_ops);