arch/arm/kernel/perf_event.c

   1 #undef DEBUG
   2
   3 /*
   4  * ARM performance counter support.
   5  *
   6  * Copyright (C) 2009 picoChip Designs, Ltd., Jamie Iles
   7  *
   8  * ARMv7 support: Jean Pihet <jpihet@mvista.com>
   9  * 2010 (c) MontaVista Software, LLC.
  10  *
  11  * This code is based on the sparc64 perf event code, which is in turn based
  12  * on the x86 code. Callchain code is based on the ARM OProfile backtrace
  13  * code.
  14  */
  15 #define pr_fmt(fmt) "hw perfevents: " fmt
  16
  17 #include <linux/interrupt.h>
  18 #include <linux/kernel.h>
  19 #include <linux/perf_event.h>
  20 #include <linux/spinlock.h>
  21 #include <linux/uaccess.h>
  22
  23 #include <asm/cputype.h>
  24 #include <asm/irq.h>
  25 #include <asm/irq_regs.h>
  26 #include <asm/pmu.h>
  27 #include <asm/stacktrace.h>
  28
  29 static const struct pmu_irqs *pmu_irqs;
  30
  31 /*
  32  * Hardware lock to serialize accesses to PMU registers. Needed for the
  33  * read/modify/write sequences.
  34  */
  35 DEFINE_SPINLOCK(pmu_lock);
  36
  37 /*
  38  * ARMv6 supports a maximum of 3 events, starting from index 1. If we add
  39  * another platform that supports more, we need to increase this to be the
  40  * largest of all platforms.
  41  *
  42  * ARMv7 supports up to 32 events:
  43  *  cycle counter CCNT + 31 events counters CNT0..30.
  44  *  Cortex-A8 has 1+4 counters, Cortex-A9 has 1+6 counters.
  45  */
  46 #define ARMPMU_MAX_HWEVENTS             33
  47
  48 /* The events for a given CPU. */
  49 struct cpu_hw_events {
  50         /*
  51          * The events that are active on the CPU for the given index. Index 0
  52          * is reserved.
  53          */
  54         struct perf_event       *events[ARMPMU_MAX_HWEVENTS];
  55
  56         /*
  57          * A 1 bit for an index indicates that the counter is being used for
  58          * an event. A 0 means that the counter can be used.
  59          */
  60         unsigned long           used_mask[BITS_TO_LONGS(ARMPMU_MAX_HWEVENTS)];
  61
  62         /*
  63          * A 1 bit for an index indicates that the counter is actively being
  64          * used.
  65          */
  66         unsigned long           active_mask[BITS_TO_LONGS(ARMPMU_MAX_HWEVENTS)];
  67 };
  68 DEFINE_PER_CPU(struct cpu_hw_events, cpu_hw_events);
  69
  70 struct arm_pmu {
  71         char            *name;
  72         irqreturn_t     (*handle_irq)(int irq_num, void *dev);
  73         void            (*enable)(struct hw_perf_event *evt, int idx);
  74         void            (*disable)(struct hw_perf_event *evt, int idx);
  75         int             (*event_map)(int evt);
  76         u64             (*raw_event)(u64);
  77         int             (*get_event_idx)(struct cpu_hw_events *cpuc,
  78                                          struct hw_perf_event *hwc);
  79         u32             (*read_counter)(int idx);
  80         void            (*write_counter)(int idx, u32 val);
  81         void            (*start)(void);
  82         void            (*stop)(void);
  83         int             num_events;
  84         u64             max_period;
  85 };
  86
  87 /* Set at runtime when we know what CPU type we are. */
  88 static const struct arm_pmu *armpmu;
  89
  90 #define HW_OP_UNSUPPORTED               0xFFFF
  91
  92 #define C(_x) \
  93         PERF_COUNT_HW_CACHE_##_x
  94
  95 #define CACHE_OP_UNSUPPORTED            0xFFFF
  96
  97 static unsigned armpmu_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
  98                                      [PERF_COUNT_HW_CACHE_OP_MAX]
  99                                      [PERF_COUNT_HW_CACHE_RESULT_MAX];
 100
 101 static int
 102 armpmu_map_cache_event(u64 config)
 103 {
 104         unsigned int cache_type, cache_op, cache_result, ret;
 105
 106         cache_type = (config >>  0) & 0xff;
 107         if (cache_type >= PERF_COUNT_HW_CACHE_MAX)
 108                 return -EINVAL;
 109
 110         cache_op = (config >>  8) & 0xff;
 111         if (cache_op >= PERF_COUNT_HW_CACHE_OP_MAX)
 112                 return -EINVAL;
 113
 114         cache_result = (config >> 16) & 0xff;
 115         if (cache_result >= PERF_COUNT_HW_CACHE_RESULT_MAX)
 116                 return -EINVAL;
 117
 118         ret = (int)armpmu_perf_cache_map[cache_type][cache_op][cache_result];
 119
 120         if (ret == CACHE_OP_UNSUPPORTED)
 121                 return -ENOENT;
 122
 123         return ret;
 124 }
 125
 126 static int
 127 armpmu_event_set_period(struct perf_event *event,
 128                         struct hw_perf_event *hwc,
 129                         int idx)
 130 {
 131         s64 left = atomic64_read(&hwc->period_left);
 132         s64 period = hwc->sample_period;
 133         int ret = 0;
 134
 135         if (unlikely(left <= -period)) {
 136                 left = period;
 137                 atomic64_set(&hwc->period_left, left);
 138                 hwc->last_period = period;
 139                 ret = 1;
 140         }
 141
 142         if (unlikely(left <= 0)) {
 143                 left += period;
 144                 atomic64_set(&hwc->period_left, left);
 145                 hwc->last_period = period;
 146                 ret = 1;
 147         }
 148
 149         if (left > (s64)armpmu->max_period)
 150                 left = armpmu->max_period;
 151
 152         atomic64_set(&hwc->prev_count, (u64)-left);
 153
 154         armpmu->write_counter(idx, (u64)(-left) & 0xffffffff);
 155
 156         perf_event_update_userpage(event);
 157
 158         return ret;
 159 }
 160
 161 static u64
 162 armpmu_event_update(struct perf_event *event,
 163                     struct hw_perf_event *hwc,
 164                     int idx)
 165 {
 166         int shift = 64 - 32;
 167         s64 prev_raw_count, new_raw_count;
 168         s64 delta;
 169
 170 again:
 171         prev_raw_count = atomic64_read(&hwc->prev_count);
 172         new_raw_count = armpmu->read_counter(idx);
 173
 174         if (atomic64_cmpxchg(&hwc->prev_count, prev_raw_count,
 175                              new_raw_count) != prev_raw_count)
 176                 goto again;
 177
 178         delta = (new_raw_count << shift) - (prev_raw_count << shift);
 179         delta >>= shift;
 180
 181         atomic64_add(delta, &event->count);
 182         atomic64_sub(delta, &hwc->period_left);
 183
 184         return new_raw_count;
 185 }
 186
 187 static void
 188 armpmu_disable(struct perf_event *event)
 189 {
 190         struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
 191         struct hw_perf_event *hwc = &event->hw;
 192         int idx = hwc->idx;
 193
 194         WARN_ON(idx < 0);
 195
 196         clear_bit(idx, cpuc->active_mask);
 197         armpmu->disable(hwc, idx);
 198
 199         barrier();
 200
 201         armpmu_event_update(event, hwc, idx);
 202         cpuc->events[idx] = NULL;
 203         clear_bit(idx, cpuc->used_mask);
 204
 205         perf_event_update_userpage(event);
 206 }
 207
 208 static void
 209 armpmu_read(struct perf_event *event)
 210 {
 211         struct hw_perf_event *hwc = &event->hw;
 212
 213         /* Don't read disabled counters! */
 214         if (hwc->idx < 0)
 215                 return;
 216
 217         armpmu_event_update(event, hwc, hwc->idx);
 218 }
 219
 220 static void
 221 armpmu_unthrottle(struct perf_event *event)
 222 {
 223         struct hw_perf_event *hwc = &event->hw;
 224
 225         /*
 226          * Set the period again. Some counters can't be stopped, so when we
 227          * were throttled we simply disabled the IRQ source and the counter
 228          * may have been left counting. If we don't do this step then we may
 229          * get an interrupt too soon or *way* too late if the overflow has
 230          * happened since disabling.
 231          */
 232         armpmu_event_set_period(event, hwc, hwc->idx);
 233         armpmu->enable(hwc, hwc->idx);
 234 }
 235
 236 static int
 237 armpmu_enable(struct perf_event *event)
 238 {
 239         struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
 240         struct hw_perf_event *hwc = &event->hw;
 241         int idx;
 242         int err = 0;
 243
 244         /* If we don't have a space for the counter then finish early. */
 245         idx = armpmu->get_event_idx(cpuc, hwc);
 246         if (idx < 0) {
 247                 err = idx;
 248                 goto out;
 249         }
 250
 251         /*
 252          * If there is an event in the counter we are going to use then make
 253          * sure it is disabled.
 254          */
 255         event->hw.idx = idx;
 256         armpmu->disable(hwc, idx);
 257         cpuc->events[idx] = event;
 258         set_bit(idx, cpuc->active_mask);
 259
 260         /* Set the period for the event. */
 261         armpmu_event_set_period(event, hwc, idx);
 262
 263         /* Enable the event. */
 264         armpmu->enable(hwc, idx);
 265
 266         /* Propagate our changes to the userspace mapping. */
 267         perf_event_update_userpage(event);
 268
 269 out:
 270         return err;
 271 }
 272
 273 static struct pmu pmu = {
 274         .enable     = armpmu_enable,
 275         .disable    = armpmu_disable,
 276         .unthrottle = armpmu_unthrottle,
 277         .read       = armpmu_read,
 278 };
 279
 280 static int
 281 validate_event(struct cpu_hw_events *cpuc,
 282                struct perf_event *event)
 283 {
 284         struct hw_perf_event fake_event = event->hw;
 285
 286         if (event->pmu && event->pmu != &pmu)
 287                 return 0;
 288
 289         return armpmu->get_event_idx(cpuc, &fake_event) >= 0;
 290 }
 291
 292 static int
 293 validate_group(struct perf_event *event)
 294 {
 295         struct perf_event *sibling, *leader = event->group_leader;
 296         struct cpu_hw_events fake_pmu;
 297
 298         memset(&fake_pmu, 0, sizeof(fake_pmu));
 299
 300         if (!validate_event(&fake_pmu, leader))
 301                 return -ENOSPC;
 302
 303         list_for_each_entry(sibling, &leader->sibling_list, group_entry) {
 304                 if (!validate_event(&fake_pmu, sibling))
 305                         return -ENOSPC;
 306         }
 307
 308         if (!validate_event(&fake_pmu, event))
 309                 return -ENOSPC;
 310
 311         return 0;
 312 }
 313
 314 static int
 315 armpmu_reserve_hardware(void)
 316 {
 317         int i;
 318         int err;
 319
 320         pmu_irqs = reserve_pmu();
 321         if (IS_ERR(pmu_irqs)) {
 322                 pr_warning("unable to reserve pmu\n");
 323                 return PTR_ERR(pmu_irqs);
 324         }
 325
 326         init_pmu();
 327
 328         if (pmu_irqs->num_irqs < 1) {
 329                 pr_err("no irqs for PMUs defined\n");
 330                 return -ENODEV;
 331         }
 332
 333         for (i = 0; i < pmu_irqs->num_irqs; ++i) {
 334                 err = request_irq(pmu_irqs->irqs[i], armpmu->handle_irq,
 335                                   IRQF_DISABLED | IRQF_NOBALANCING,
 336                                   "armpmu", NULL);
 337                 if (err) {
 338                         pr_warning("unable to request IRQ%d for ARM "
 339                                    "perf counters\n", pmu_irqs->irqs[i]);
 340                         break;
 341                 }
 342         }
 343
 344         if (err) {
 345                 for (i = i - 1; i >= 0; --i)
 346                         free_irq(pmu_irqs->irqs[i], NULL);
 347                 release_pmu(pmu_irqs);
 348                 pmu_irqs = NULL;
 349         }
 350
 351         return err;
 352 }
 353
 354 static void
 355 armpmu_release_hardware(void)
 356 {
 357         int i;
 358
 359         for (i = pmu_irqs->num_irqs - 1; i >= 0; --i)
 360                 free_irq(pmu_irqs->irqs[i], NULL);
 361         armpmu->stop();
 362
 363         release_pmu(pmu_irqs);
 364         pmu_irqs = NULL;
 365 }
 366
 367 static atomic_t active_events = ATOMIC_INIT(0);
 368 static DEFINE_MUTEX(pmu_reserve_mutex);
 369
 370 static void
 371 hw_perf_event_destroy(struct perf_event *event)
 372 {
 373         if (atomic_dec_and_mutex_lock(&active_events, &pmu_reserve_mutex)) {
 374                 armpmu_release_hardware();
 375                 mutex_unlock(&pmu_reserve_mutex);
 376         }
 377 }
 378
 379 static int
 380 __hw_perf_event_init(struct perf_event *event)
 381 {
 382         struct hw_perf_event *hwc = &event->hw;
 383         int mapping, err;
 384
 385         /* Decode the generic type into an ARM event identifier. */
 386         if (PERF_TYPE_HARDWARE == event->attr.type) {
 387                 mapping = armpmu->event_map(event->attr.config);
 388         } else if (PERF_TYPE_HW_CACHE == event->attr.type) {
 389                 mapping = armpmu_map_cache_event(event->attr.config);
 390         } else if (PERF_TYPE_RAW == event->attr.type) {
 391                 mapping = armpmu->raw_event(event->attr.config);
 392         } else {
 393                 pr_debug("event type %x not supported\n", event->attr.type);
 394                 return -EOPNOTSUPP;
 395         }
 396
 397         if (mapping < 0) {
 398                 pr_debug("event %x:%llx not supported\n", event->attr.type,
 399                          event->attr.config);
 400                 return mapping;
 401         }
 402
 403         /*
 404          * Check whether we need to exclude the counter from certain modes.
 405          * The ARM performance counters are on all of the time so if someone
 406          * has asked us for some excludes then we have to fail.
 407          */
 408         if (event->attr.exclude_kernel || event->attr.exclude_user ||
 409             event->attr.exclude_hv || event->attr.exclude_idle) {
 410                 pr_debug("ARM performance counters do not support "
 411                          "mode exclusion\n");
 412                 return -EPERM;
 413         }
 414
 415         /*
 416          * We don't assign an index until we actually place the event onto
 417          * hardware. Use -1 to signify that we haven't decided where to put it
 418          * yet. For SMP systems, each core has it's own PMU so we can't do any
 419          * clever allocation or constraints checking at this point.
 420          */
 421         hwc->idx = -1;
 422
 423         /*
 424          * Store the event encoding into the config_base field. config and
 425          * event_base are unused as the only 2 things we need to know are
 426          * the event mapping and the counter to use. The counter to use is
 427          * also the indx and the config_base is the event type.
 428          */
 429         hwc->config_base            = (unsigned long)mapping;
 430         hwc->config                 = 0;
 431         hwc->event_base             = 0;
 432
 433         if (!hwc->sample_period) {
 434                 hwc->sample_period  = armpmu->max_period;
 435                 hwc->last_period    = hwc->sample_period;
 436                 atomic64_set(&hwc->period_left, hwc->sample_period);
 437         }
 438
 439         err = 0;
 440         if (event->group_leader != event) {
 441                 err = validate_group(event);
 442                 if (err)
 443                         return -EINVAL;
 444         }
 445
 446         return err;
 447 }
 448
 449 const struct pmu *
 450 hw_perf_event_init(struct perf_event *event)
 451 {
 452         int err = 0;
 453
 454         if (!armpmu)
 455                 return ERR_PTR(-ENODEV);
 456
 457         event->destroy = hw_perf_event_destroy;
 458
 459         if (!atomic_inc_not_zero(&active_events)) {
 460                 if (atomic_read(&active_events) > perf_max_events) {
 461                         atomic_dec(&active_events);
 462                         return ERR_PTR(-ENOSPC);
 463                 }
 464
 465                 mutex_lock(&pmu_reserve_mutex);
 466                 if (atomic_read(&active_events) == 0) {
 467                         err = armpmu_reserve_hardware();
 468                 }
 469
 470                 if (!err)
 471                         atomic_inc(&active_events);
 472                 mutex_unlock(&pmu_reserve_mutex);
 473         }
 474
 475         if (err)
 476                 return ERR_PTR(err);
 477
 478         err = __hw_perf_event_init(event);
 479         if (err)
 480                 hw_perf_event_destroy(event);
 481
 482         return err ? ERR_PTR(err) : &pmu;
 483 }
 484
 485 void
 486 hw_perf_enable(void)
 487 {
 488         /* Enable all of the perf events on hardware. */
 489         int idx;
 490         struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
 491
 492         if (!armpmu)
 493                 return;
 494
 495         for (idx = 0; idx <= armpmu->num_events; ++idx) {
 496                 struct perf_event *event = cpuc->events[idx];
 497
 498                 if (!event)
 499                         continue;
 500
 501                 armpmu->enable(&event->hw, idx);
 502         }
 503
 504         armpmu->start();
 505 }
 506
 507 void
 508 hw_perf_disable(void)
 509 {
 510         if (armpmu)
 511                 armpmu->stop();
 512 }
 513
 514 /*
 515  * ARMv6 Performance counter handling code.
 516  *
 517  * ARMv6 has 2 configurable performance counters and a single cycle counter.
 518  * They all share a single reset bit but can be written to zero so we can use
 519  * that for a reset.
 520  *
 521  * The counters can't be individually enabled or disabled so when we remove
 522  * one event and replace it with another we could get spurious counts from the
 523  * wrong event. However, we can take advantage of the fact that the
 524  * performance counters can export events to the event bus, and the event bus
 525  * itself can be monitored. This requires that we *don't* export the events to
 526  * the event bus. The procedure for disabling a configurable counter is:
 527  *      - change the counter to count the ETMEXTOUT[0] signal (0x20). This
 528  *        effectively stops the counter from counting.
 529  *      - disable the counter's interrupt generation (each counter has it's
 530  *        own interrupt enable bit).
 531  * Once stopped, the counter value can be written as 0 to reset.
 532  *
 533  * To enable a counter:
 534  *      - enable the counter's interrupt generation.
 535  *      - set the new event type.
 536  *
 537  * Note: the dedicated cycle counter only counts cycles and can't be
 538  * enabled/disabled independently of the others. When we want to disable the
 539  * cycle counter, we have to just disable the interrupt reporting and start
 540  * ignoring that counter. When re-enabling, we have to reset the value and
 541  * enable the interrupt.
 542  */
 543
 544 enum armv6_perf_types {
 545         ARMV6_PERFCTR_ICACHE_MISS           = 0x0,
 546         ARMV6_PERFCTR_IBUF_STALL            = 0x1,
 547         ARMV6_PERFCTR_DDEP_STALL            = 0x2,
 548         ARMV6_PERFCTR_ITLB_MISS             = 0x3,
 549         ARMV6_PERFCTR_DTLB_MISS             = 0x4,
 550         ARMV6_PERFCTR_BR_EXEC               = 0x5,
 551         ARMV6_PERFCTR_BR_MISPREDICT         = 0x6,
 552         ARMV6_PERFCTR_INSTR_EXEC            = 0x7,
 553         ARMV6_PERFCTR_DCACHE_HIT            = 0x9,
 554         ARMV6_PERFCTR_DCACHE_ACCESS         = 0xA,
 555         ARMV6_PERFCTR_DCACHE_MISS           = 0xB,
 556         ARMV6_PERFCTR_DCACHE_WBACK          = 0xC,
 557         ARMV6_PERFCTR_SW_PC_CHANGE          = 0xD,
 558         ARMV6_PERFCTR_MAIN_TLB_MISS         = 0xF,
 559         ARMV6_PERFCTR_EXPL_D_ACCESS         = 0x10,
 560         ARMV6_PERFCTR_LSU_FULL_STALL        = 0x11,
 561         ARMV6_PERFCTR_WBUF_DRAINED          = 0x12,
 562         ARMV6_PERFCTR_CPU_CYCLES            = 0xFF,
 563         ARMV6_PERFCTR_NOP                   = 0x20,
 564 };
 565
 566 enum armv6_counters {
 567         ARMV6_CYCLE_COUNTER = 1,
 568         ARMV6_COUNTER0,
 569         ARMV6_COUNTER1,
 570 };
 571
 572 /*
 573  * The hardware events that we support. We do support cache operations but
 574  * we have harvard caches and no way to combine instruction and data
 575  * accesses/misses in hardware.
 576  */
 577 static const unsigned armv6_perf_map[PERF_COUNT_HW_MAX] = {
 578         [PERF_COUNT_HW_CPU_CYCLES]          = ARMV6_PERFCTR_CPU_CYCLES,
 579         [PERF_COUNT_HW_INSTRUCTIONS]        = ARMV6_PERFCTR_INSTR_EXEC,
 580         [PERF_COUNT_HW_CACHE_REFERENCES]    = HW_OP_UNSUPPORTED,
 581         [PERF_COUNT_HW_CACHE_MISSES]        = HW_OP_UNSUPPORTED,
 582         [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = ARMV6_PERFCTR_BR_EXEC,
 583         [PERF_COUNT_HW_BRANCH_MISSES]       = ARMV6_PERFCTR_BR_MISPREDICT,
 584         [PERF_COUNT_HW_BUS_CYCLES]          = HW_OP_UNSUPPORTED,
 585 };
 586
 587 static const unsigned armv6_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
 588                                           [PERF_COUNT_HW_CACHE_OP_MAX]
 589                                           [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
 590         [C(L1D)] = {
 591                 /*
 592                  * The performance counters don't differentiate between read
 593                  * and write accesses/misses so this isn't strictly correct,
 594                  * but it's the best we can do. Writes and reads get
 595                  * combined.
 596                  */
 597                 [C(OP_READ)] = {
 598                         [C(RESULT_ACCESS)]      = ARMV6_PERFCTR_DCACHE_ACCESS,
 599                         [C(RESULT_MISS)]        = ARMV6_PERFCTR_DCACHE_MISS,
 600                 },
 601                 [C(OP_WRITE)] = {
 602                         [C(RESULT_ACCESS)]      = ARMV6_PERFCTR_DCACHE_ACCESS,
 603                         [C(RESULT_MISS)]        = ARMV6_PERFCTR_DCACHE_MISS,
 604                 },
 605                 [C(OP_PREFETCH)] = {
 606                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 607                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
 608                 },
 609         },
 610         [C(L1I)] = {
 611                 [C(OP_READ)] = {
 612                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 613                         [C(RESULT_MISS)]        = ARMV6_PERFCTR_ICACHE_MISS,
 614                 },
 615                 [C(OP_WRITE)] = {
 616                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 617                         [C(RESULT_MISS)]        = ARMV6_PERFCTR_ICACHE_MISS,
 618                 },
 619                 [C(OP_PREFETCH)] = {
 620                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 621                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
 622                 },
 623         },
 624         [C(LL)] = {
 625                 [C(OP_READ)] = {
 626                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 627                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
 628                 },
 629                 [C(OP_WRITE)] = {
 630                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 631                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
 632                 },
 633                 [C(OP_PREFETCH)] = {
 634                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 635                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
 636                 },
 637         },
 638         [C(DTLB)] = {
 639                 /*
 640                  * The ARM performance counters can count micro DTLB misses,
 641                  * micro ITLB misses and main TLB misses. There isn't an event
 642                  * for TLB misses, so use the micro misses here and if users
 643                  * want the main TLB misses they can use a raw counter.
 644                  */
 645                 [C(OP_READ)] = {
 646                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 647                         [C(RESULT_MISS)]        = ARMV6_PERFCTR_DTLB_MISS,
 648                 },
 649                 [C(OP_WRITE)] = {
 650                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 651                         [C(RESULT_MISS)]        = ARMV6_PERFCTR_DTLB_MISS,
 652                 },
 653                 [C(OP_PREFETCH)] = {
 654                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 655                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
 656                 },
 657         },
 658         [C(ITLB)] = {
 659                 [C(OP_READ)] = {
 660                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 661                         [C(RESULT_MISS)]        = ARMV6_PERFCTR_ITLB_MISS,
 662                 },
 663                 [C(OP_WRITE)] = {
 664                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 665                         [C(RESULT_MISS)]        = ARMV6_PERFCTR_ITLB_MISS,
 666                 },
 667                 [C(OP_PREFETCH)] = {
 668                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 669                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
 670                 },
 671         },
 672         [C(BPU)] = {
 673                 [C(OP_READ)] = {
 674                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 675                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
 676                 },
 677                 [C(OP_WRITE)] = {
 678                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 679                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
 680                 },
 681                 [C(OP_PREFETCH)] = {
 682                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 683                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
 684                 },
 685         },
 686 };
 687
 688 enum armv6mpcore_perf_types {
 689         ARMV6MPCORE_PERFCTR_ICACHE_MISS     = 0x0,
 690         ARMV6MPCORE_PERFCTR_IBUF_STALL      = 0x1,
 691         ARMV6MPCORE_PERFCTR_DDEP_STALL      = 0x2,
 692         ARMV6MPCORE_PERFCTR_ITLB_MISS       = 0x3,
 693         ARMV6MPCORE_PERFCTR_DTLB_MISS       = 0x4,
 694         ARMV6MPCORE_PERFCTR_BR_EXEC         = 0x5,
 695         ARMV6MPCORE_PERFCTR_BR_NOTPREDICT   = 0x6,
 696         ARMV6MPCORE_PERFCTR_BR_MISPREDICT   = 0x7,
 697         ARMV6MPCORE_PERFCTR_INSTR_EXEC      = 0x8,
 698         ARMV6MPCORE_PERFCTR_DCACHE_RDACCESS = 0xA,
 699         ARMV6MPCORE_PERFCTR_DCACHE_RDMISS   = 0xB,
 700         ARMV6MPCORE_PERFCTR_DCACHE_WRACCESS = 0xC,
 701         ARMV6MPCORE_PERFCTR_DCACHE_WRMISS   = 0xD,
 702         ARMV6MPCORE_PERFCTR_DCACHE_EVICTION = 0xE,
 703         ARMV6MPCORE_PERFCTR_SW_PC_CHANGE    = 0xF,
 704         ARMV6MPCORE_PERFCTR_MAIN_TLB_MISS   = 0x10,
 705         ARMV6MPCORE_PERFCTR_EXPL_MEM_ACCESS = 0x11,
 706         ARMV6MPCORE_PERFCTR_LSU_FULL_STALL  = 0x12,
 707         ARMV6MPCORE_PERFCTR_WBUF_DRAINED    = 0x13,
 708         ARMV6MPCORE_PERFCTR_CPU_CYCLES      = 0xFF,
 709 };
 710
 711 /*
 712  * The hardware events that we support. We do support cache operations but
 713  * we have harvard caches and no way to combine instruction and data
 714  * accesses/misses in hardware.
 715  */
 716 static const unsigned armv6mpcore_perf_map[PERF_COUNT_HW_MAX] = {
 717         [PERF_COUNT_HW_CPU_CYCLES]          = ARMV6MPCORE_PERFCTR_CPU_CYCLES,
 718         [PERF_COUNT_HW_INSTRUCTIONS]        = ARMV6MPCORE_PERFCTR_INSTR_EXEC,
 719         [PERF_COUNT_HW_CACHE_REFERENCES]    = HW_OP_UNSUPPORTED,
 720         [PERF_COUNT_HW_CACHE_MISSES]        = HW_OP_UNSUPPORTED,
 721         [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = ARMV6MPCORE_PERFCTR_BR_EXEC,
 722         [PERF_COUNT_HW_BRANCH_MISSES]       = ARMV6MPCORE_PERFCTR_BR_MISPREDICT,
 723         [PERF_COUNT_HW_BUS_CYCLES]          = HW_OP_UNSUPPORTED,
 724 };
 725
 726 static const unsigned armv6mpcore_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
 727                                         [PERF_COUNT_HW_CACHE_OP_MAX]
 728                                         [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
 729         [C(L1D)] = {
 730                 [C(OP_READ)] = {
 731                         [C(RESULT_ACCESS)]  =
 732                                 ARMV6MPCORE_PERFCTR_DCACHE_RDACCESS,
 733                         [C(RESULT_MISS)]    =
 734                                 ARMV6MPCORE_PERFCTR_DCACHE_RDMISS,
 735                 },
 736                 [C(OP_WRITE)] = {
 737                         [C(RESULT_ACCESS)]  =
 738                                 ARMV6MPCORE_PERFCTR_DCACHE_WRACCESS,
 739                         [C(RESULT_MISS)]    =
 740                                 ARMV6MPCORE_PERFCTR_DCACHE_WRMISS,
 741                 },
 742                 [C(OP_PREFETCH)] = {
 743                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 744                         [C(RESULT_MISS)]    = CACHE_OP_UNSUPPORTED,
 745                 },
 746         },
 747         [C(L1I)] = {
 748                 [C(OP_READ)] = {
 749                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 750                         [C(RESULT_MISS)]    = ARMV6MPCORE_PERFCTR_ICACHE_MISS,
 751                 },
 752                 [C(OP_WRITE)] = {
 753                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 754                         [C(RESULT_MISS)]    = ARMV6MPCORE_PERFCTR_ICACHE_MISS,
 755                 },
 756                 [C(OP_PREFETCH)] = {
 757                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 758                         [C(RESULT_MISS)]    = CACHE_OP_UNSUPPORTED,
 759                 },
 760         },
 761         [C(LL)] = {
 762                 [C(OP_READ)] = {
 763                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 764                         [C(RESULT_MISS)]    = CACHE_OP_UNSUPPORTED,
 765                 },
 766                 [C(OP_WRITE)] = {
 767                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 768                         [C(RESULT_MISS)]    = CACHE_OP_UNSUPPORTED,
 769                 },
 770                 [C(OP_PREFETCH)] = {
 771                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 772                         [C(RESULT_MISS)]    = CACHE_OP_UNSUPPORTED,
 773                 },
 774         },
 775         [C(DTLB)] = {
 776                 /*
 777                  * The ARM performance counters can count micro DTLB misses,
 778                  * micro ITLB misses and main TLB misses. There isn't an event
 779                  * for TLB misses, so use the micro misses here and if users
 780                  * want the main TLB misses they can use a raw counter.
 781                  */
 782                 [C(OP_READ)] = {
 783                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 784                         [C(RESULT_MISS)]    = ARMV6MPCORE_PERFCTR_DTLB_MISS,
 785                 },
 786                 [C(OP_WRITE)] = {
 787                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 788                         [C(RESULT_MISS)]    = ARMV6MPCORE_PERFCTR_DTLB_MISS,
 789                 },
 790                 [C(OP_PREFETCH)] = {
 791                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 792                         [C(RESULT_MISS)]    = CACHE_OP_UNSUPPORTED,
 793                 },
 794         },
 795         [C(ITLB)] = {
 796                 [C(OP_READ)] = {
 797                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 798                         [C(RESULT_MISS)]    = ARMV6MPCORE_PERFCTR_ITLB_MISS,
 799                 },
 800                 [C(OP_WRITE)] = {
 801                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 802                         [C(RESULT_MISS)]    = ARMV6MPCORE_PERFCTR_ITLB_MISS,
 803                 },
 804                 [C(OP_PREFETCH)] = {
 805                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 806                         [C(RESULT_MISS)]    = CACHE_OP_UNSUPPORTED,
 807                 },
 808         },
 809         [C(BPU)] = {
 810                 [C(OP_READ)] = {
 811                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 812                         [C(RESULT_MISS)]    = CACHE_OP_UNSUPPORTED,
 813                 },
 814                 [C(OP_WRITE)] = {
 815                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 816                         [C(RESULT_MISS)]    = CACHE_OP_UNSUPPORTED,
 817                 },
 818                 [C(OP_PREFETCH)] = {
 819                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 820                         [C(RESULT_MISS)]    = CACHE_OP_UNSUPPORTED,
 821                 },
 822         },
 823 };
 824
 825 static inline unsigned long
 826 armv6_pmcr_read(void)
 827 {
 828         u32 val;
 829         asm volatile("mrc   p15, 0, %0, c15, c12, 0" : "=r"(val));
 830         return val;
 831 }
 832
 833 static inline void
 834 armv6_pmcr_write(unsigned long val)
 835 {
 836         asm volatile("mcr   p15, 0, %0, c15, c12, 0" : : "r"(val));
 837 }
 838
 839 #define ARMV6_PMCR_ENABLE               (1 << 0)
 840 #define ARMV6_PMCR_CTR01_RESET          (1 << 1)
 841 #define ARMV6_PMCR_CCOUNT_RESET         (1 << 2)
 842 #define ARMV6_PMCR_CCOUNT_DIV           (1 << 3)
 843 #define ARMV6_PMCR_COUNT0_IEN           (1 << 4)
 844 #define ARMV6_PMCR_COUNT1_IEN           (1 << 5)
 845 #define ARMV6_PMCR_CCOUNT_IEN           (1 << 6)
 846 #define ARMV6_PMCR_COUNT0_OVERFLOW      (1 << 8)
 847 #define ARMV6_PMCR_COUNT1_OVERFLOW      (1 << 9)
 848 #define ARMV6_PMCR_CCOUNT_OVERFLOW      (1 << 10)
 849 #define ARMV6_PMCR_EVT_COUNT0_SHIFT     20
 850 #define ARMV6_PMCR_EVT_COUNT0_MASK      (0xFF << ARMV6_PMCR_EVT_COUNT0_SHIFT)
 851 #define ARMV6_PMCR_EVT_COUNT1_SHIFT     12
 852 #define ARMV6_PMCR_EVT_COUNT1_MASK      (0xFF << ARMV6_PMCR_EVT_COUNT1_SHIFT)
 853
 854 #define ARMV6_PMCR_OVERFLOWED_MASK \
 855         (ARMV6_PMCR_COUNT0_OVERFLOW | ARMV6_PMCR_COUNT1_OVERFLOW | \
 856          ARMV6_PMCR_CCOUNT_OVERFLOW)
 857
 858 static inline int
 859 armv6_pmcr_has_overflowed(unsigned long pmcr)
 860 {
 861         return (pmcr & ARMV6_PMCR_OVERFLOWED_MASK);
 862 }
 863
 864 static inline int
 865 armv6_pmcr_counter_has_overflowed(unsigned long pmcr,
 866                                   enum armv6_counters counter)
 867 {
 868         int ret = 0;
 869
 870         if (ARMV6_CYCLE_COUNTER == counter)
 871                 ret = pmcr & ARMV6_PMCR_CCOUNT_OVERFLOW;
 872         else if (ARMV6_COUNTER0 == counter)
 873                 ret = pmcr & ARMV6_PMCR_COUNT0_OVERFLOW;
 874         else if (ARMV6_COUNTER1 == counter)
 875                 ret = pmcr & ARMV6_PMCR_COUNT1_OVERFLOW;
 876         else
 877                 WARN_ONCE(1, "invalid counter number (%d)\n", counter);
 878
 879         return ret;
 880 }
 881
 882 static inline u32
 883 armv6pmu_read_counter(int counter)
 884 {
 885         unsigned long value = 0;
 886
 887         if (ARMV6_CYCLE_COUNTER == counter)
 888                 asm volatile("mrc   p15, 0, %0, c15, c12, 1" : "=r"(value));
 889         else if (ARMV6_COUNTER0 == counter)
 890                 asm volatile("mrc   p15, 0, %0, c15, c12, 2" : "=r"(value));
 891         else if (ARMV6_COUNTER1 == counter)
 892                 asm volatile("mrc   p15, 0, %0, c15, c12, 3" : "=r"(value));
 893         else
 894                 WARN_ONCE(1, "invalid counter number (%d)\n", counter);
 895
 896         return value;
 897 }
 898
 899 static inline void
 900 armv6pmu_write_counter(int counter,
 901                        u32 value)
 902 {
 903         if (ARMV6_CYCLE_COUNTER == counter)
 904                 asm volatile("mcr   p15, 0, %0, c15, c12, 1" : : "r"(value));
 905         else if (ARMV6_COUNTER0 == counter)
 906                 asm volatile("mcr   p15, 0, %0, c15, c12, 2" : : "r"(value));
 907         else if (ARMV6_COUNTER1 == counter)
 908                 asm volatile("mcr   p15, 0, %0, c15, c12, 3" : : "r"(value));
 909         else
 910                 WARN_ONCE(1, "invalid counter number (%d)\n", counter);
 911 }
 912
 913 void
 914 armv6pmu_enable_event(struct hw_perf_event *hwc,
 915                       int idx)
 916 {
 917         unsigned long val, mask, evt, flags;
 918
 919         if (ARMV6_CYCLE_COUNTER == idx) {
 920                 mask    = 0;
 921                 evt     = ARMV6_PMCR_CCOUNT_IEN;
 922         } else if (ARMV6_COUNTER0 == idx) {
 923                 mask    = ARMV6_PMCR_EVT_COUNT0_MASK;
 924                 evt     = (hwc->config_base << ARMV6_PMCR_EVT_COUNT0_SHIFT) |
 925                           ARMV6_PMCR_COUNT0_IEN;
 926         } else if (ARMV6_COUNTER1 == idx) {
 927                 mask    = ARMV6_PMCR_EVT_COUNT1_MASK;
 928                 evt     = (hwc->config_base << ARMV6_PMCR_EVT_COUNT1_SHIFT) |
 929                           ARMV6_PMCR_COUNT1_IEN;
 930         } else {
 931                 WARN_ONCE(1, "invalid counter number (%d)\n", idx);
 932                 return;
 933         }
 934
 935         /*
 936          * Mask out the current event and set the counter to count the event
 937          * that we're interested in.
 938          */
 939         spin_lock_irqsave(&pmu_lock, flags);
 940         val = armv6_pmcr_read();
 941         val &= ~mask;
 942         val |= evt;
 943         armv6_pmcr_write(val);
 944         spin_unlock_irqrestore(&pmu_lock, flags);
 945 }
 946
 947 static irqreturn_t
 948 armv6pmu_handle_irq(int irq_num,
 949                     void *dev)
 950 {
 951         unsigned long pmcr = armv6_pmcr_read();
 952         struct perf_sample_data data;
 953         struct cpu_hw_events *cpuc;
 954         struct pt_regs *regs;
 955         int idx;
 956
 957         if (!armv6_pmcr_has_overflowed(pmcr))
 958                 return IRQ_NONE;
 959
 960         regs = get_irq_regs();
 961
 962         /*
 963          * The interrupts are cleared by writing the overflow flags back to
 964          * the control register. All of the other bits don't have any effect
 965          * if they are rewritten, so write the whole value back.
 966          */
 967         armv6_pmcr_write(pmcr);
 968
 969         perf_sample_data_init(&data, 0);
 970
 971         cpuc = &__get_cpu_var(cpu_hw_events);
 972         for (idx = 0; idx <= armpmu->num_events; ++idx) {
 973                 struct perf_event *event = cpuc->events[idx];
 974                 struct hw_perf_event *hwc;
 975
 976                 if (!test_bit(idx, cpuc->active_mask))
 977                         continue;
 978
 979                 /*
 980                  * We have a single interrupt for all counters. Check that
 981                  * each counter has overflowed before we process it.
 982                  */
 983                 if (!armv6_pmcr_counter_has_overflowed(pmcr, idx))
 984                         continue;
 985
 986                 hwc = &event->hw;
 987                 armpmu_event_update(event, hwc, idx);
 988                 data.period = event->hw.last_period;
 989                 if (!armpmu_event_set_period(event, hwc, idx))
 990                         continue;
 991
 992                 if (perf_event_overflow(event, 0, &data, regs))
 993                         armpmu->disable(hwc, idx);
 994         }
 995
 996         /*
 997          * Handle the pending perf events.
 998          *
 999          * Note: this call *must* be run with interrupts enabled. For
1000          * platforms that can have the PMU interrupts raised as a PMI, this
1001          * will not work.
1002          */
1003         perf_event_do_pending();
1004
1005         return IRQ_HANDLED;
1006 }
1007
1008 static void
1009 armv6pmu_start(void)
1010 {
1011         unsigned long flags, val;
1012
1013         spin_lock_irqsave(&pmu_lock, flags);
1014         val = armv6_pmcr_read();
1015         val |= ARMV6_PMCR_ENABLE;
1016         armv6_pmcr_write(val);
1017         spin_unlock_irqrestore(&pmu_lock, flags);
1018 }
1019
1020 void
1021 armv6pmu_stop(void)
1022 {
1023         unsigned long flags, val;
1024
1025         spin_lock_irqsave(&pmu_lock, flags);
1026         val = armv6_pmcr_read();
1027         val &= ~ARMV6_PMCR_ENABLE;
1028         armv6_pmcr_write(val);
1029         spin_unlock_irqrestore(&pmu_lock, flags);
1030 }
1031
1032 static inline int
1033 armv6pmu_event_map(int config)
1034 {
1035         int mapping = armv6_perf_map[config];
1036         if (HW_OP_UNSUPPORTED == mapping)
1037                 mapping = -EOPNOTSUPP;
1038         return mapping;
1039 }
1040
1041 static inline int
1042 armv6mpcore_pmu_event_map(int config)
1043 {
1044         int mapping = armv6mpcore_perf_map[config];
1045         if (HW_OP_UNSUPPORTED == mapping)
1046                 mapping = -EOPNOTSUPP;
1047         return mapping;
1048 }
1049
1050 static u64
1051 armv6pmu_raw_event(u64 config)
1052 {
1053         return config & 0xff;
1054 }
1055
1056 static int
1057 armv6pmu_get_event_idx(struct cpu_hw_events *cpuc,
1058                        struct hw_perf_event *event)
1059 {
1060         /* Always place a cycle counter into the cycle counter. */
1061         if (ARMV6_PERFCTR_CPU_CYCLES == event->config_base) {
1062                 if (test_and_set_bit(ARMV6_CYCLE_COUNTER, cpuc->used_mask))
1063                         return -EAGAIN;
1064
1065                 return ARMV6_CYCLE_COUNTER;
1066         } else {
1067                 /*
1068                  * For anything other than a cycle counter, try and use
1069                  * counter0 and counter1.
1070                  */
1071                 if (!test_and_set_bit(ARMV6_COUNTER1, cpuc->used_mask)) {
1072                         return ARMV6_COUNTER1;
1073                 }
1074
1075                 if (!test_and_set_bit(ARMV6_COUNTER0, cpuc->used_mask)) {
1076                         return ARMV6_COUNTER0;
1077                 }
1078
1079                 /* The counters are all in use. */
1080                 return -EAGAIN;
1081         }
1082 }
1083
1084 static void
1085 armv6pmu_disable_event(struct hw_perf_event *hwc,
1086                        int idx)
1087 {
1088         unsigned long val, mask, evt, flags;
1089
1090         if (ARMV6_CYCLE_COUNTER == idx) {
1091                 mask    = ARMV6_PMCR_CCOUNT_IEN;
1092                 evt     = 0;
1093         } else if (ARMV6_COUNTER0 == idx) {
1094                 mask    = ARMV6_PMCR_COUNT0_IEN | ARMV6_PMCR_EVT_COUNT0_MASK;
1095                 evt     = ARMV6_PERFCTR_NOP << ARMV6_PMCR_EVT_COUNT0_SHIFT;
1096         } else if (ARMV6_COUNTER1 == idx) {
1097                 mask    = ARMV6_PMCR_COUNT1_IEN | ARMV6_PMCR_EVT_COUNT1_MASK;
1098                 evt     = ARMV6_PERFCTR_NOP << ARMV6_PMCR_EVT_COUNT1_SHIFT;
1099         } else {
1100                 WARN_ONCE(1, "invalid counter number (%d)\n", idx);
1101                 return;
1102         }
1103
1104         /*
1105          * Mask out the current event and set the counter to count the number
1106          * of ETM bus signal assertion cycles. The external reporting should
1107          * be disabled and so this should never increment.
1108          */
1109         spin_lock_irqsave(&pmu_lock, flags);
1110         val = armv6_pmcr_read();
1111         val &= ~mask;
1112         val |= evt;
1113         armv6_pmcr_write(val);
1114         spin_unlock_irqrestore(&pmu_lock, flags);
1115 }
1116
1117 static void
1118 armv6mpcore_pmu_disable_event(struct hw_perf_event *hwc,
1119                               int idx)
1120 {
1121         unsigned long val, mask, flags, evt = 0;
1122
1123         if (ARMV6_CYCLE_COUNTER == idx) {
1124                 mask    = ARMV6_PMCR_CCOUNT_IEN;
1125         } else if (ARMV6_COUNTER0 == idx) {
1126                 mask    = ARMV6_PMCR_COUNT0_IEN;
1127         } else if (ARMV6_COUNTER1 == idx) {
1128                 mask    = ARMV6_PMCR_COUNT1_IEN;
1129         } else {
1130                 WARN_ONCE(1, "invalid counter number (%d)\n", idx);
1131                 return;
1132         }
1133
1134         /*
1135          * Unlike UP ARMv6, we don't have a way of stopping the counters. We
1136          * simply disable the interrupt reporting.
1137          */
1138         spin_lock_irqsave(&pmu_lock, flags);
1139         val = armv6_pmcr_read();
1140         val &= ~mask;
1141         val |= evt;
1142         armv6_pmcr_write(val);
1143         spin_unlock_irqrestore(&pmu_lock, flags);
1144 }
1145
1146 static const struct arm_pmu armv6pmu = {
1147         .name                   = "v6",
1148         .handle_irq             = armv6pmu_handle_irq,
1149         .enable                 = armv6pmu_enable_event,
1150         .disable                = armv6pmu_disable_event,
1151         .event_map              = armv6pmu_event_map,
1152         .raw_event              = armv6pmu_raw_event,
1153         .read_counter           = armv6pmu_read_counter,
1154         .write_counter          = armv6pmu_write_counter,
1155         .get_event_idx          = armv6pmu_get_event_idx,
1156         .start                  = armv6pmu_start,
1157         .stop                   = armv6pmu_stop,
1158         .num_events             = 3,
1159         .max_period             = (1LLU << 32) - 1,
1160 };
1161
1162 /*
1163  * ARMv6mpcore is almost identical to single core ARMv6 with the exception
1164  * that some of the events have different enumerations and that there is no
1165  * *hack* to stop the programmable counters. To stop the counters we simply
1166  * disable the interrupt reporting and update the event. When unthrottling we
1167  * reset the period and enable the interrupt reporting.
1168  */
1169 static const struct arm_pmu armv6mpcore_pmu = {
1170         .name                   = "v6mpcore",
1171         .handle_irq             = armv6pmu_handle_irq,
1172         .enable                 = armv6pmu_enable_event,
1173         .disable                = armv6mpcore_pmu_disable_event,
1174         .event_map              = armv6mpcore_pmu_event_map,
1175         .raw_event              = armv6pmu_raw_event,
1176         .read_counter           = armv6pmu_read_counter,
1177         .write_counter          = armv6pmu_write_counter,
1178         .get_event_idx          = armv6pmu_get_event_idx,
1179         .start                  = armv6pmu_start,
1180         .stop                   = armv6pmu_stop,
1181         .num_events             = 3,
1182         .max_period             = (1LLU << 32) - 1,
1183 };
1184
1185 /*
1186  * ARMv7 Cortex-A8 and Cortex-A9 Performance Events handling code.
1187  *
1188  * Copied from ARMv6 code, with the low level code inspired
1189  *  by the ARMv7 Oprofile code.
1190  *
1191  * Cortex-A8 has up to 4 configurable performance counters and
1192  *  a single cycle counter.
1193  * Cortex-A9 has up to 31 configurable performance counters and
1194  *  a single cycle counter.
1195  *
1196  * All counters can be enabled/disabled and IRQ masked separately. The cycle
1197  *  counter and all 4 performance counters together can be reset separately.
1198  */
1199
1200 #define ARMV7_PMU_CORTEX_A8_NAME                "ARMv7 Cortex-A8"
1201
1202 #define ARMV7_PMU_CORTEX_A9_NAME                "ARMv7 Cortex-A9"
1203
1204 /* Common ARMv7 event types */
1205 enum armv7_perf_types {
1206         ARMV7_PERFCTR_PMNC_SW_INCR              = 0x00,
1207         ARMV7_PERFCTR_IFETCH_MISS               = 0x01,
1208         ARMV7_PERFCTR_ITLB_MISS                 = 0x02,
1209         ARMV7_PERFCTR_DCACHE_REFILL             = 0x03,
1210         ARMV7_PERFCTR_DCACHE_ACCESS             = 0x04,
1211         ARMV7_PERFCTR_DTLB_REFILL               = 0x05,
1212         ARMV7_PERFCTR_DREAD                     = 0x06,
1213         ARMV7_PERFCTR_DWRITE                    = 0x07,
1214
1215         ARMV7_PERFCTR_EXC_TAKEN                 = 0x09,
1216         ARMV7_PERFCTR_EXC_EXECUTED              = 0x0A,
1217         ARMV7_PERFCTR_CID_WRITE                 = 0x0B,
1218         /* ARMV7_PERFCTR_PC_WRITE is equivalent to HW_BRANCH_INSTRUCTIONS.
1219          * It counts:
1220          *  - all branch instructions,
1221          *  - instructions that explicitly write the PC,
1222          *  - exception generating instructions.
1223          */
1224         ARMV7_PERFCTR_PC_WRITE                  = 0x0C,
1225         ARMV7_PERFCTR_PC_IMM_BRANCH             = 0x0D,
1226         ARMV7_PERFCTR_UNALIGNED_ACCESS          = 0x0F,
1227         ARMV7_PERFCTR_PC_BRANCH_MIS_PRED        = 0x10,
1228         ARMV7_PERFCTR_CLOCK_CYCLES              = 0x11,
1229
1230         ARMV7_PERFCTR_PC_BRANCH_MIS_USED        = 0x12,
1231
1232         ARMV7_PERFCTR_CPU_CYCLES                = 0xFF
1233 };
1234
1235 /* ARMv7 Cortex-A8 specific event types */
1236 enum armv7_a8_perf_types {
1237         ARMV7_PERFCTR_INSTR_EXECUTED            = 0x08,
1238
1239         ARMV7_PERFCTR_PC_PROC_RETURN            = 0x0E,
1240
1241         ARMV7_PERFCTR_WRITE_BUFFER_FULL         = 0x40,
1242         ARMV7_PERFCTR_L2_STORE_MERGED           = 0x41,
1243         ARMV7_PERFCTR_L2_STORE_BUFF             = 0x42,
1244         ARMV7_PERFCTR_L2_ACCESS                 = 0x43,
1245         ARMV7_PERFCTR_L2_CACH_MISS              = 0x44,
1246         ARMV7_PERFCTR_AXI_READ_CYCLES           = 0x45,
1247         ARMV7_PERFCTR_AXI_WRITE_CYCLES          = 0x46,
1248         ARMV7_PERFCTR_MEMORY_REPLAY             = 0x47,
1249         ARMV7_PERFCTR_UNALIGNED_ACCESS_REPLAY   = 0x48,
1250         ARMV7_PERFCTR_L1_DATA_MISS              = 0x49,
1251         ARMV7_PERFCTR_L1_INST_MISS              = 0x4A,
1252         ARMV7_PERFCTR_L1_DATA_COLORING          = 0x4B,
1253         ARMV7_PERFCTR_L1_NEON_DATA              = 0x4C,
1254         ARMV7_PERFCTR_L1_NEON_CACH_DATA         = 0x4D,
1255         ARMV7_PERFCTR_L2_NEON                   = 0x4E,
1256         ARMV7_PERFCTR_L2_NEON_HIT               = 0x4F,
1257         ARMV7_PERFCTR_L1_INST                   = 0x50,
1258         ARMV7_PERFCTR_PC_RETURN_MIS_PRED        = 0x51,
1259         ARMV7_PERFCTR_PC_BRANCH_FAILED          = 0x52,
1260         ARMV7_PERFCTR_PC_BRANCH_TAKEN           = 0x53,
1261         ARMV7_PERFCTR_PC_BRANCH_EXECUTED        = 0x54,
1262         ARMV7_PERFCTR_OP_EXECUTED               = 0x55,
1263         ARMV7_PERFCTR_CYCLES_INST_STALL         = 0x56,
1264         ARMV7_PERFCTR_CYCLES_INST               = 0x57,
1265         ARMV7_PERFCTR_CYCLES_NEON_DATA_STALL    = 0x58,
1266         ARMV7_PERFCTR_CYCLES_NEON_INST_STALL    = 0x59,
1267         ARMV7_PERFCTR_NEON_CYCLES               = 0x5A,
1268
1269         ARMV7_PERFCTR_PMU0_EVENTS               = 0x70,
1270         ARMV7_PERFCTR_PMU1_EVENTS               = 0x71,
1271         ARMV7_PERFCTR_PMU_EVENTS                = 0x72,
1272 };
1273
1274 /* ARMv7 Cortex-A9 specific event types */
1275 enum armv7_a9_perf_types {
1276         ARMV7_PERFCTR_JAVA_HW_BYTECODE_EXEC     = 0x40,
1277         ARMV7_PERFCTR_JAVA_SW_BYTECODE_EXEC     = 0x41,
1278         ARMV7_PERFCTR_JAZELLE_BRANCH_EXEC       = 0x42,
1279
1280         ARMV7_PERFCTR_COHERENT_LINE_MISS        = 0x50,
1281         ARMV7_PERFCTR_COHERENT_LINE_HIT         = 0x51,
1282
1283         ARMV7_PERFCTR_ICACHE_DEP_STALL_CYCLES   = 0x60,
1284         ARMV7_PERFCTR_DCACHE_DEP_STALL_CYCLES   = 0x61,
1285         ARMV7_PERFCTR_TLB_MISS_DEP_STALL_CYCLES = 0x62,
1286         ARMV7_PERFCTR_STREX_EXECUTED_PASSED     = 0x63,
1287         ARMV7_PERFCTR_STREX_EXECUTED_FAILED     = 0x64,
1288         ARMV7_PERFCTR_DATA_EVICTION             = 0x65,
1289         ARMV7_PERFCTR_ISSUE_STAGE_NO_INST       = 0x66,
1290         ARMV7_PERFCTR_ISSUE_STAGE_EMPTY         = 0x67,
1291         ARMV7_PERFCTR_INST_OUT_OF_RENAME_STAGE  = 0x68,
1292
1293         ARMV7_PERFCTR_PREDICTABLE_FUNCT_RETURNS = 0x6E,
1294
1295         ARMV7_PERFCTR_MAIN_UNIT_EXECUTED_INST   = 0x70,
1296         ARMV7_PERFCTR_SECOND_UNIT_EXECUTED_INST = 0x71,
1297         ARMV7_PERFCTR_LD_ST_UNIT_EXECUTED_INST  = 0x72,
1298         ARMV7_PERFCTR_FP_EXECUTED_INST          = 0x73,
1299         ARMV7_PERFCTR_NEON_EXECUTED_INST        = 0x74,
1300
1301         ARMV7_PERFCTR_PLD_FULL_DEP_STALL_CYCLES = 0x80,
1302         ARMV7_PERFCTR_DATA_WR_DEP_STALL_CYCLES  = 0x81,
1303         ARMV7_PERFCTR_ITLB_MISS_DEP_STALL_CYCLES        = 0x82,
1304         ARMV7_PERFCTR_DTLB_MISS_DEP_STALL_CYCLES        = 0x83,
1305         ARMV7_PERFCTR_MICRO_ITLB_MISS_DEP_STALL_CYCLES  = 0x84,
1306         ARMV7_PERFCTR_MICRO_DTLB_MISS_DEP_STALL_CYCLES  = 0x85,
1307         ARMV7_PERFCTR_DMB_DEP_STALL_CYCLES      = 0x86,
1308
1309         ARMV7_PERFCTR_INTGR_CLK_ENABLED_CYCLES  = 0x8A,
1310         ARMV7_PERFCTR_DATA_ENGINE_CLK_EN_CYCLES = 0x8B,
1311
1312         ARMV7_PERFCTR_ISB_INST                  = 0x90,
1313         ARMV7_PERFCTR_DSB_INST                  = 0x91,
1314         ARMV7_PERFCTR_DMB_INST                  = 0x92,
1315         ARMV7_PERFCTR_EXT_INTERRUPTS            = 0x93,
1316
1317         ARMV7_PERFCTR_PLE_CACHE_LINE_RQST_COMPLETED     = 0xA0,
1318         ARMV7_PERFCTR_PLE_CACHE_LINE_RQST_SKIPPED       = 0xA1,
1319         ARMV7_PERFCTR_PLE_FIFO_FLUSH            = 0xA2,
1320         ARMV7_PERFCTR_PLE_RQST_COMPLETED        = 0xA3,
1321         ARMV7_PERFCTR_PLE_FIFO_OVERFLOW         = 0xA4,
1322         ARMV7_PERFCTR_PLE_RQST_PROG             = 0xA5
1323 };
1324
1325 /*
1326  * Cortex-A8 HW events mapping
1327  *
1328  * The hardware events that we support. We do support cache operations but
1329  * we have harvard caches and no way to combine instruction and data
1330  * accesses/misses in hardware.
1331  */
1332 static const unsigned armv7_a8_perf_map[PERF_COUNT_HW_MAX] = {
1333         [PERF_COUNT_HW_CPU_CYCLES]          = ARMV7_PERFCTR_CPU_CYCLES,
1334         [PERF_COUNT_HW_INSTRUCTIONS]        = ARMV7_PERFCTR_INSTR_EXECUTED,
1335         [PERF_COUNT_HW_CACHE_REFERENCES]    = HW_OP_UNSUPPORTED,
1336         [PERF_COUNT_HW_CACHE_MISSES]        = HW_OP_UNSUPPORTED,
1337         [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = ARMV7_PERFCTR_PC_WRITE,
1338         [PERF_COUNT_HW_BRANCH_MISSES]       = ARMV7_PERFCTR_PC_BRANCH_MIS_PRED,
1339         [PERF_COUNT_HW_BUS_CYCLES]          = ARMV7_PERFCTR_CLOCK_CYCLES,
1340 };
1341
1342 static const unsigned armv7_a8_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
1343                                           [PERF_COUNT_HW_CACHE_OP_MAX]
1344                                           [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
1345         [C(L1D)] = {
1346                 /*
1347                  * The performance counters don't differentiate between read
1348                  * and write accesses/misses so this isn't strictly correct,
1349                  * but it's the best we can do. Writes and reads get
1350                  * combined.
1351                  */
1352                 [C(OP_READ)] = {
1353                         [C(RESULT_ACCESS)]      = ARMV7_PERFCTR_DCACHE_ACCESS,
1354                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_DCACHE_REFILL,
1355                 },
1356                 [C(OP_WRITE)] = {
1357                         [C(RESULT_ACCESS)]      = ARMV7_PERFCTR_DCACHE_ACCESS,
1358                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_DCACHE_REFILL,
1359                 },
1360                 [C(OP_PREFETCH)] = {
1361                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1362                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
1363                 },
1364         },
1365         [C(L1I)] = {
1366                 [C(OP_READ)] = {
1367                         [C(RESULT_ACCESS)]      = ARMV7_PERFCTR_L1_INST,
1368                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_L1_INST_MISS,
1369                 },
1370                 [C(OP_WRITE)] = {
1371                         [C(RESULT_ACCESS)]      = ARMV7_PERFCTR_L1_INST,
1372                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_L1_INST_MISS,
1373                 },
1374                 [C(OP_PREFETCH)] = {
1375                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1376                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
1377                 },
1378         },
1379         [C(LL)] = {
1380                 [C(OP_READ)] = {
1381                         [C(RESULT_ACCESS)]      = ARMV7_PERFCTR_L2_ACCESS,
1382                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_L2_CACH_MISS,
1383                 },
1384                 [C(OP_WRITE)] = {
1385                         [C(RESULT_ACCESS)]      = ARMV7_PERFCTR_L2_ACCESS,
1386                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_L2_CACH_MISS,
1387                 },
1388                 [C(OP_PREFETCH)] = {
1389                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1390                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
1391                 },
1392         },
1393         [C(DTLB)] = {
1394                 /*
1395                  * Only ITLB misses and DTLB refills are supported.
1396                  * If users want the DTLB refills misses a raw counter
1397                  * must be used.
1398                  */
1399                 [C(OP_READ)] = {
1400                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1401                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_DTLB_REFILL,
1402                 },
1403                 [C(OP_WRITE)] = {
1404                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1405                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_DTLB_REFILL,
1406                 },
1407                 [C(OP_PREFETCH)] = {
1408                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1409                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
1410                 },
1411         },
1412         [C(ITLB)] = {
1413                 [C(OP_READ)] = {
1414                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1415                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_ITLB_MISS,
1416                 },
1417                 [C(OP_WRITE)] = {
1418                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1419                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_ITLB_MISS,
1420                 },
1421                 [C(OP_PREFETCH)] = {
1422                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1423                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
1424                 },
1425         },
1426         [C(BPU)] = {
1427                 [C(OP_READ)] = {
1428                         [C(RESULT_ACCESS)]      = ARMV7_PERFCTR_PC_WRITE,
1429                         [C(RESULT_MISS)]
1430                                         = ARMV7_PERFCTR_PC_BRANCH_MIS_PRED,
1431                 },
1432                 [C(OP_WRITE)] = {
1433                         [C(RESULT_ACCESS)]      = ARMV7_PERFCTR_PC_WRITE,
1434                         [C(RESULT_MISS)]
1435                                         = ARMV7_PERFCTR_PC_BRANCH_MIS_PRED,
1436                 },
1437                 [C(OP_PREFETCH)] = {
1438                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1439                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
1440                 },
1441         },
1442 };
1443
1444 /*
1445  * Cortex-A9 HW events mapping
1446  */
1447 static const unsigned armv7_a9_perf_map[PERF_COUNT_HW_MAX] = {
1448         [PERF_COUNT_HW_CPU_CYCLES]          = ARMV7_PERFCTR_CPU_CYCLES,
1449         [PERF_COUNT_HW_INSTRUCTIONS]        =
1450                                         ARMV7_PERFCTR_INST_OUT_OF_RENAME_STAGE,
1451         [PERF_COUNT_HW_CACHE_REFERENCES]    = ARMV7_PERFCTR_COHERENT_LINE_HIT,
1452         [PERF_COUNT_HW_CACHE_MISSES]        = ARMV7_PERFCTR_COHERENT_LINE_MISS,
1453         [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = ARMV7_PERFCTR_PC_WRITE,
1454         [PERF_COUNT_HW_BRANCH_MISSES]       = ARMV7_PERFCTR_PC_BRANCH_MIS_PRED,
1455         [PERF_COUNT_HW_BUS_CYCLES]          = ARMV7_PERFCTR_CLOCK_CYCLES,
1456 };
1457
1458 static const unsigned armv7_a9_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
1459                                           [PERF_COUNT_HW_CACHE_OP_MAX]
1460                                           [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
1461         [C(L1D)] = {
1462                 /*
1463                  * The performance counters don't differentiate between read
1464                  * and write accesses/misses so this isn't strictly correct,
1465                  * but it's the best we can do. Writes and reads get
1466                  * combined.
1467                  */
1468                 [C(OP_READ)] = {
1469                         [C(RESULT_ACCESS)]      = ARMV7_PERFCTR_DCACHE_ACCESS,
1470                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_DCACHE_REFILL,
1471                 },
1472                 [C(OP_WRITE)] = {
1473                         [C(RESULT_ACCESS)]      = ARMV7_PERFCTR_DCACHE_ACCESS,
1474                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_DCACHE_REFILL,
1475                 },
1476                 [C(OP_PREFETCH)] = {
1477                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1478                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
1479                 },
1480         },
1481         [C(L1I)] = {
1482                 [C(OP_READ)] = {
1483                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1484                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_IFETCH_MISS,
1485                 },
1486                 [C(OP_WRITE)] = {
1487                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1488                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_IFETCH_MISS,
1489                 },
1490                 [C(OP_PREFETCH)] = {
1491                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1492                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
1493                 },
1494         },
1495         [C(LL)] = {
1496                 [C(OP_READ)] = {
1497                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1498                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
1499                 },
1500                 [C(OP_WRITE)] = {
1501                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1502                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
1503                 },
1504                 [C(OP_PREFETCH)] = {
1505                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1506                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
1507                 },
1508         },
1509         [C(DTLB)] = {
1510                 /*
1511                  * Only ITLB misses and DTLB refills are supported.
1512                  * If users want the DTLB refills misses a raw counter
1513                  * must be used.
1514                  */
1515                 [C(OP_READ)] = {
1516                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1517                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_DTLB_REFILL,
1518                 },
1519                 [C(OP_WRITE)] = {
1520                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1521                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_DTLB_REFILL,
1522                 },
1523                 [C(OP_PREFETCH)] = {
1524                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1525                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
1526                 },
1527         },
1528         [C(ITLB)] = {
1529                 [C(OP_READ)] = {
1530                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1531                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_ITLB_MISS,
1532                 },
1533                 [C(OP_WRITE)] = {
1534                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1535                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_ITLB_MISS,
1536                 },
1537                 [C(OP_PREFETCH)] = {
1538                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1539                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
1540                 },
1541         },
1542         [C(BPU)] = {
1543                 [C(OP_READ)] = {
1544                         [C(RESULT_ACCESS)]      = ARMV7_PERFCTR_PC_WRITE,
1545                         [C(RESULT_MISS)]
1546                                         = ARMV7_PERFCTR_PC_BRANCH_MIS_PRED,
1547                 },
1548                 [C(OP_WRITE)] = {
1549                         [C(RESULT_ACCESS)]      = ARMV7_PERFCTR_PC_WRITE,
1550                         [C(RESULT_MISS)]
1551                                         = ARMV7_PERFCTR_PC_BRANCH_MIS_PRED,
1552                 },
1553                 [C(OP_PREFETCH)] = {
1554                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1555                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
1556                 },
1557         },
1558 };
1559
1560 /*
1561  * Perf Events counters
1562  */
1563 enum armv7_counters {
1564         ARMV7_CYCLE_COUNTER             = 1,    /* Cycle counter */
1565         ARMV7_COUNTER0                  = 2,    /* First event counter */
1566 };
1567
1568 /*
1569  * The cycle counter is ARMV7_CYCLE_COUNTER.
1570  * The first event counter is ARMV7_COUNTER0.
1571  * The last event counter is (ARMV7_COUNTER0 + armpmu->num_events - 1).
1572  */
1573 #define ARMV7_COUNTER_LAST      (ARMV7_COUNTER0 + armpmu->num_events - 1)
1574
1575 /*
1576  * ARMv7 low level PMNC access
1577  */
1578
1579 /*
1580  * Per-CPU PMNC: config reg
1581  */
1582 #define ARMV7_PMNC_E            (1 << 0) /* Enable all counters */
1583 #define ARMV7_PMNC_P            (1 << 1) /* Reset all counters */
1584 #define ARMV7_PMNC_C            (1 << 2) /* Cycle counter reset */
1585 #define ARMV7_PMNC_D            (1 << 3) /* CCNT counts every 64th cpu cycle */
1586 #define ARMV7_PMNC_X            (1 << 4) /* Export to ETM */
1587 #define ARMV7_PMNC_DP           (1 << 5) /* Disable CCNT if non-invasive debug*/
1588 #define ARMV7_PMNC_N_SHIFT      11       /* Number of counters supported */
1589 #define ARMV7_PMNC_N_MASK       0x1f
1590 #define ARMV7_PMNC_MASK         0x3f     /* Mask for writable bits */
1591
1592 /*
1593  * Available counters
1594  */
1595 #define ARMV7_CNT0              0       /* First event counter */
1596 #define ARMV7_CCNT              31      /* Cycle counter */
1597
1598 /* Perf Event to low level counters mapping */
1599 #define ARMV7_EVENT_CNT_TO_CNTx (ARMV7_COUNTER0 - ARMV7_CNT0)
1600
1601 /*
1602  * CNTENS: counters enable reg
1603  */
1604 #define ARMV7_CNTENS_P(idx)     (1 << (idx - ARMV7_EVENT_CNT_TO_CNTx))
1605 #define ARMV7_CNTENS_C          (1 << ARMV7_CCNT)
1606
1607 /*
1608  * CNTENC: counters disable reg
1609  */
1610 #define ARMV7_CNTENC_P(idx)     (1 << (idx - ARMV7_EVENT_CNT_TO_CNTx))
1611 #define ARMV7_CNTENC_C          (1 << ARMV7_CCNT)
1612
1613 /*
1614  * INTENS: counters overflow interrupt enable reg
1615  */
1616 #define ARMV7_INTENS_P(idx)     (1 << (idx - ARMV7_EVENT_CNT_TO_CNTx))
1617 #define ARMV7_INTENS_C          (1 << ARMV7_CCNT)
1618
1619 /*
1620  * INTENC: counters overflow interrupt disable reg
1621  */
1622 #define ARMV7_INTENC_P(idx)     (1 << (idx - ARMV7_EVENT_CNT_TO_CNTx))
1623 #define ARMV7_INTENC_C          (1 << ARMV7_CCNT)
1624
1625 /*
1626  * EVTSEL: Event selection reg
1627  */
1628 #define ARMV7_EVTSEL_MASK       0xff            /* Mask for writable bits */
1629
1630 /*
1631  * SELECT: Counter selection reg
1632  */
1633 #define ARMV7_SELECT_MASK       0x1f            /* Mask for writable bits */
1634
1635 /*
1636  * FLAG: counters overflow flag status reg
1637  */
1638 #define ARMV7_FLAG_P(idx)       (1 << (idx - ARMV7_EVENT_CNT_TO_CNTx))
1639 #define ARMV7_FLAG_C            (1 << ARMV7_CCNT)
1640 #define ARMV7_FLAG_MASK         0xffffffff      /* Mask for writable bits */
1641 #define ARMV7_OVERFLOWED_MASK   ARMV7_FLAG_MASK
1642
1643 static inline unsigned long armv7_pmnc_read(void)
1644 {
1645         u32 val;
1646         asm volatile("mrc p15, 0, %0, c9, c12, 0" : "=r"(val));
1647         return val;
1648 }
1649
1650 static inline void armv7_pmnc_write(unsigned long val)
1651 {
1652         val &= ARMV7_PMNC_MASK;
1653         asm volatile("mcr p15, 0, %0, c9, c12, 0" : : "r"(val));
1654 }
1655
1656 static inline int armv7_pmnc_has_overflowed(unsigned long pmnc)
1657 {
1658         return pmnc & ARMV7_OVERFLOWED_MASK;
1659 }
1660
1661 static inline int armv7_pmnc_counter_has_overflowed(unsigned long pmnc,
1662                                         enum armv7_counters counter)
1663 {
1664         int ret;
1665
1666         if (counter == ARMV7_CYCLE_COUNTER)
1667                 ret = pmnc & ARMV7_FLAG_C;
1668         else if ((counter >= ARMV7_COUNTER0) && (counter <= ARMV7_COUNTER_LAST))
1669                 ret = pmnc & ARMV7_FLAG_P(counter);
1670         else
1671                 pr_err("CPU%u checking wrong counter %d overflow status\n",
1672                         smp_processor_id(), counter);
1673
1674         return ret;
1675 }
1676
1677 static inline int armv7_pmnc_select_counter(unsigned int idx)
1678 {
1679         u32 val;
1680
1681         if ((idx < ARMV7_COUNTER0) || (idx > ARMV7_COUNTER_LAST)) {
1682                 pr_err("CPU%u selecting wrong PMNC counter"
1683                         " %d\n", smp_processor_id(), idx);
1684                 return -1;
1685         }
1686
1687         val = (idx - ARMV7_EVENT_CNT_TO_CNTx) & ARMV7_SELECT_MASK;
1688         asm volatile("mcr p15, 0, %0, c9, c12, 5" : : "r" (val));
1689
1690         return idx;
1691 }
1692
1693 static inline u32 armv7pmu_read_counter(int idx)
1694 {
1695         unsigned long value = 0;
1696
1697         if (idx == ARMV7_CYCLE_COUNTER)
1698                 asm volatile("mrc p15, 0, %0, c9, c13, 0" : "=r" (value));
1699         else if ((idx >= ARMV7_COUNTER0) && (idx <= ARMV7_COUNTER_LAST)) {
1700                 if (armv7_pmnc_select_counter(idx) == idx)
1701                         asm volatile("mrc p15, 0, %0, c9, c13, 2"
1702                                      : "=r" (value));
1703         } else
1704                 pr_err("CPU%u reading wrong counter %d\n",
1705                         smp_processor_id(), idx);
1706
1707         return value;
1708 }
1709
1710 static inline void armv7pmu_write_counter(int idx, u32 value)
1711 {
1712         if (idx == ARMV7_CYCLE_COUNTER)
1713                 asm volatile("mcr p15, 0, %0, c9, c13, 0" : : "r" (value));
1714         else if ((idx >= ARMV7_COUNTER0) && (idx <= ARMV7_COUNTER_LAST)) {
1715                 if (armv7_pmnc_select_counter(idx) == idx)
1716                         asm volatile("mcr p15, 0, %0, c9, c13, 2"
1717                                      : : "r" (value));
1718         } else
1719                 pr_err("CPU%u writing wrong counter %d\n",
1720                         smp_processor_id(), idx);
1721 }
1722
1723 static inline void armv7_pmnc_write_evtsel(unsigned int idx, u32 val)
1724 {
1725         if (armv7_pmnc_select_counter(idx) == idx) {
1726                 val &= ARMV7_EVTSEL_MASK;
1727                 asm volatile("mcr p15, 0, %0, c9, c13, 1" : : "r" (val));
1728         }
1729 }
1730
1731 static inline u32 armv7_pmnc_enable_counter(unsigned int idx)
1732 {
1733         u32 val;
1734
1735         if ((idx != ARMV7_CYCLE_COUNTER) &&
1736             ((idx < ARMV7_COUNTER0) || (idx > ARMV7_COUNTER_LAST))) {
1737                 pr_err("CPU%u enabling wrong PMNC counter"
1738                         " %d\n", smp_processor_id(), idx);
1739                 return -1;
1740         }
1741
1742         if (idx == ARMV7_CYCLE_COUNTER)
1743                 val = ARMV7_CNTENS_C;
1744         else
1745                 val = ARMV7_CNTENS_P(idx);
1746
1747         asm volatile("mcr p15, 0, %0, c9, c12, 1" : : "r" (val));
1748
1749         return idx;
1750 }
1751
1752 static inline u32 armv7_pmnc_disable_counter(unsigned int idx)
1753 {
1754         u32 val;
1755
1756
1757         if ((idx != ARMV7_CYCLE_COUNTER) &&
1758             ((idx < ARMV7_COUNTER0) || (idx > ARMV7_COUNTER_LAST))) {
1759                 pr_err("CPU%u disabling wrong PMNC counter"
1760                         " %d\n", smp_processor_id(), idx);
1761                 return -1;
1762         }
1763
1764         if (idx == ARMV7_CYCLE_COUNTER)
1765                 val = ARMV7_CNTENC_C;
1766         else
1767                 val = ARMV7_CNTENC_P(idx);
1768
1769         asm volatile("mcr p15, 0, %0, c9, c12, 2" : : "r" (val));
1770
1771         return idx;
1772 }
1773
1774 static inline u32 armv7_pmnc_enable_intens(unsigned int idx)
1775 {
1776         u32 val;
1777
1778         if ((idx != ARMV7_CYCLE_COUNTER) &&
1779             ((idx < ARMV7_COUNTER0) || (idx > ARMV7_COUNTER_LAST))) {
1780                 pr_err("CPU%u enabling wrong PMNC counter"
1781                         " interrupt enable %d\n", smp_processor_id(), idx);
1782                 return -1;
1783         }
1784
1785         if (idx == ARMV7_CYCLE_COUNTER)
1786                 val = ARMV7_INTENS_C;
1787         else
1788                 val = ARMV7_INTENS_P(idx);
1789
1790         asm volatile("mcr p15, 0, %0, c9, c14, 1" : : "r" (val));
1791
1792         return idx;
1793 }
1794
1795 static inline u32 armv7_pmnc_disable_intens(unsigned int idx)
1796 {
1797         u32 val;
1798
1799         if ((idx != ARMV7_CYCLE_COUNTER) &&
1800             ((idx < ARMV7_COUNTER0) || (idx > ARMV7_COUNTER_LAST))) {
1801                 pr_err("CPU%u disabling wrong PMNC counter"
1802                         " interrupt enable %d\n", smp_processor_id(), idx);
1803                 return -1;
1804         }
1805
1806         if (idx == ARMV7_CYCLE_COUNTER)
1807                 val = ARMV7_INTENC_C;
1808         else
1809                 val = ARMV7_INTENC_P(idx);
1810
1811         asm volatile("mcr p15, 0, %0, c9, c14, 2" : : "r" (val));
1812
1813         return idx;
1814 }
1815
1816 static inline u32 armv7_pmnc_getreset_flags(void)
1817 {
1818         u32 val;
1819
1820         /* Read */
1821         asm volatile("mrc p15, 0, %0, c9, c12, 3" : "=r" (val));
1822
1823         /* Write to clear flags */
1824         val &= ARMV7_FLAG_MASK;
1825         asm volatile("mcr p15, 0, %0, c9, c12, 3" : : "r" (val));
1826
1827         return val;
1828 }
1829
1830 #ifdef DEBUG
1831 static void armv7_pmnc_dump_regs(void)
1832 {
1833         u32 val;
1834         unsigned int cnt;
1835
1836         printk(KERN_INFO "PMNC registers dump:\n");
1837
1838         asm volatile("mrc p15, 0, %0, c9, c12, 0" : "=r" (val));
1839         printk(KERN_INFO "PMNC  =0x%08x\n", val);
1840
1841         asm volatile("mrc p15, 0, %0, c9, c12, 1" : "=r" (val));
1842         printk(KERN_INFO "CNTENS=0x%08x\n", val);
1843
1844         asm volatile("mrc p15, 0, %0, c9, c14, 1" : "=r" (val));
1845         printk(KERN_INFO "INTENS=0x%08x\n", val);
1846
1847         asm volatile("mrc p15, 0, %0, c9, c12, 3" : "=r" (val));
1848         printk(KERN_INFO "FLAGS =0x%08x\n", val);
1849
1850         asm volatile("mrc p15, 0, %0, c9, c12, 5" : "=r" (val));
1851         printk(KERN_INFO "SELECT=0x%08x\n", val);
1852
1853         asm volatile("mrc p15, 0, %0, c9, c13, 0" : "=r" (val));
1854         printk(KERN_INFO "CCNT  =0x%08x\n", val);
1855
1856         for (cnt = ARMV7_COUNTER0; cnt < ARMV7_COUNTER_LAST; cnt++) {
1857                 armv7_pmnc_select_counter(cnt);
1858                 asm volatile("mrc p15, 0, %0, c9, c13, 2" : "=r" (val));
1859                 printk(KERN_INFO "CNT[%d] count =0x%08x\n",
1860                         cnt-ARMV7_EVENT_CNT_TO_CNTx, val);
1861                 asm volatile("mrc p15, 0, %0, c9, c13, 1" : "=r" (val));
1862                 printk(KERN_INFO "CNT[%d] evtsel=0x%08x\n",
1863                         cnt-ARMV7_EVENT_CNT_TO_CNTx, val);
1864         }
1865 }
1866 #endif
1867
1868 void armv7pmu_enable_event(struct hw_perf_event *hwc, int idx)
1869 {
1870         unsigned long flags;
1871
1872         /*
1873          * Enable counter and interrupt, and set the counter to count
1874          * the event that we're interested in.
1875          */
1876         spin_lock_irqsave(&pmu_lock, flags);
1877
1878         /*
1879          * Disable counter
1880          */
1881         armv7_pmnc_disable_counter(idx);
1882
1883         /*
1884          * Set event (if destined for PMNx counters)
1885          * We don't need to set the event if it's a cycle count
1886          */
1887         if (idx != ARMV7_CYCLE_COUNTER)
1888                 armv7_pmnc_write_evtsel(idx, hwc->config_base);
1889
1890         /*
1891          * Enable interrupt for this counter
1892          */
1893         armv7_pmnc_enable_intens(idx);
1894
1895         /*
1896          * Enable counter
1897          */
1898         armv7_pmnc_enable_counter(idx);
1899
1900         spin_unlock_irqrestore(&pmu_lock, flags);
1901 }
1902
1903 static void armv7pmu_disable_event(struct hw_perf_event *hwc, int idx)
1904 {
1905         unsigned long flags;
1906
1907         /*
1908          * Disable counter and interrupt
1909          */
1910         spin_lock_irqsave(&pmu_lock, flags);
1911
1912         /*
1913          * Disable counter
1914          */
1915         armv7_pmnc_disable_counter(idx);
1916
1917         /*
1918          * Disable interrupt for this counter
1919          */
1920         armv7_pmnc_disable_intens(idx);
1921
1922         spin_unlock_irqrestore(&pmu_lock, flags);
1923 }
1924
1925 static irqreturn_t armv7pmu_handle_irq(int irq_num, void *dev)
1926 {
1927         unsigned long pmnc;
1928         struct perf_sample_data data;
1929         struct cpu_hw_events *cpuc;
1930         struct pt_regs *regs;
1931         int idx;
1932
1933         /*
1934          * Get and reset the IRQ flags
1935          */
1936         pmnc = armv7_pmnc_getreset_flags();
1937
1938         /*
1939          * Did an overflow occur?
1940          */
1941         if (!armv7_pmnc_has_overflowed(pmnc))
1942                 return IRQ_NONE;
1943
1944         /*
1945          * Handle the counter(s) overflow(s)
1946          */
1947         regs = get_irq_regs();
1948
1949         perf_sample_data_init(&data, 0);
1950
1951         cpuc = &__get_cpu_var(cpu_hw_events);
1952         for (idx = 0; idx <= armpmu->num_events; ++idx) {
1953                 struct perf_event *event = cpuc->events[idx];
1954                 struct hw_perf_event *hwc;
1955
1956                 if (!test_bit(idx, cpuc->active_mask))
1957                         continue;
1958
1959                 /*
1960                  * We have a single interrupt for all counters. Check that
1961                  * each counter has overflowed before we process it.
1962                  */
1963                 if (!armv7_pmnc_counter_has_overflowed(pmnc, idx))
1964                         continue;
1965
1966                 hwc = &event->hw;
1967                 armpmu_event_update(event, hwc, idx);
1968                 data.period = event->hw.last_period;
1969                 if (!armpmu_event_set_period(event, hwc, idx))
1970                         continue;
1971
1972                 if (perf_event_overflow(event, 0, &data, regs))
1973                         armpmu->disable(hwc, idx);
1974         }
1975
1976         /*
1977          * Handle the pending perf events.
1978          *
1979          * Note: this call *must* be run with interrupts enabled. For
1980          * platforms that can have the PMU interrupts raised as a PMI, this
1981          * will not work.
1982          */
1983         perf_event_do_pending();
1984
1985         return IRQ_HANDLED;
1986 }
1987
1988 static void armv7pmu_start(void)
1989 {
1990         unsigned long flags;
1991
1992         spin_lock_irqsave(&pmu_lock, flags);
1993         /* Enable all counters */
1994         armv7_pmnc_write(armv7_pmnc_read() | ARMV7_PMNC_E);
1995         spin_unlock_irqrestore(&pmu_lock, flags);
1996 }
1997
1998 static void armv7pmu_stop(void)
1999 {
2000         unsigned long flags;
2001
2002         spin_lock_irqsave(&pmu_lock, flags);
2003         /* Disable all counters */
2004         armv7_pmnc_write(armv7_pmnc_read() & ~ARMV7_PMNC_E);
2005         spin_unlock_irqrestore(&pmu_lock, flags);
2006 }
2007
2008 static inline int armv7_a8_pmu_event_map(int config)
2009 {
2010         int mapping = armv7_a8_perf_map[config];
2011         if (HW_OP_UNSUPPORTED == mapping)
2012                 mapping = -EOPNOTSUPP;
2013         return mapping;
2014 }
2015
2016 static inline int armv7_a9_pmu_event_map(int config)
2017 {
2018         int mapping = armv7_a9_perf_map[config];
2019         if (HW_OP_UNSUPPORTED == mapping)
2020                 mapping = -EOPNOTSUPP;
2021         return mapping;
2022 }
2023
2024 static u64 armv7pmu_raw_event(u64 config)
2025 {
2026         return config & 0xff;
2027 }
2028
2029 static int armv7pmu_get_event_idx(struct cpu_hw_events *cpuc,
2030                                   struct hw_perf_event *event)
2031 {
2032         int idx;
2033
2034         /* Always place a cycle counter into the cycle counter. */
2035         if (event->config_base == ARMV7_PERFCTR_CPU_CYCLES) {
2036                 if (test_and_set_bit(ARMV7_CYCLE_COUNTER, cpuc->used_mask))
2037                         return -EAGAIN;
2038
2039                 return ARMV7_CYCLE_COUNTER;
2040         } else {
2041                 /*
2042                  * For anything other than a cycle counter, try and use
2043                  * the events counters
2044                  */
2045                 for (idx = ARMV7_COUNTER0; idx <= armpmu->num_events; ++idx) {
2046                         if (!test_and_set_bit(idx, cpuc->used_mask))
2047                                 return idx;
2048                 }
2049
2050                 /* The counters are all in use. */
2051                 return -EAGAIN;
2052         }
2053 }
2054
2055 static struct arm_pmu armv7pmu = {
2056         .handle_irq             = armv7pmu_handle_irq,
2057         .enable                 = armv7pmu_enable_event,
2058         .disable                = armv7pmu_disable_event,
2059         .raw_event              = armv7pmu_raw_event,
2060         .read_counter           = armv7pmu_read_counter,
2061         .write_counter          = armv7pmu_write_counter,
2062         .get_event_idx          = armv7pmu_get_event_idx,
2063         .start                  = armv7pmu_start,
2064         .stop                   = armv7pmu_stop,
2065         .max_period             = (1LLU << 32) - 1,
2066 };
2067
2068 static u32 __init armv7_reset_read_pmnc(void)
2069 {
2070         u32 nb_cnt;
2071
2072         /* Initialize & Reset PMNC: C and P bits */
2073         armv7_pmnc_write(ARMV7_PMNC_P | ARMV7_PMNC_C);
2074
2075         /* Read the nb of CNTx counters supported from PMNC */
2076         nb_cnt = (armv7_pmnc_read() >> ARMV7_PMNC_N_SHIFT) & ARMV7_PMNC_N_MASK;
2077
2078         /* Add the CPU cycles counter and return */
2079         return nb_cnt + 1;
2080 }
2081
2082 static int __init
2083 init_hw_perf_events(void)
2084 {
2085         unsigned long cpuid = read_cpuid_id();
2086         unsigned long implementor = (cpuid & 0xFF000000) >> 24;
2087         unsigned long part_number = (cpuid & 0xFFF0);
2088
2089         /* We only support ARM CPUs implemented by ARM at the moment. */
2090         if (0x41 == implementor) {
2091                 switch (part_number) {
2092                 case 0xB360:    /* ARM1136 */
2093                 case 0xB560:    /* ARM1156 */
2094                 case 0xB760:    /* ARM1176 */
2095                         armpmu = &armv6pmu;
2096                         memcpy(armpmu_perf_cache_map, armv6_perf_cache_map,
2097                                         sizeof(armv6_perf_cache_map));
2098                         perf_max_events = armv6pmu.num_events;
2099                         break;
2100                 case 0xB020:    /* ARM11mpcore */
2101                         armpmu = &armv6mpcore_pmu;
2102                         memcpy(armpmu_perf_cache_map,
2103                                armv6mpcore_perf_cache_map,
2104                                sizeof(armv6mpcore_perf_cache_map));
2105                         perf_max_events = armv6mpcore_pmu.num_events;
2106                         break;
2107                 case 0xC080:    /* Cortex-A8 */
2108                         armv7pmu.name = ARMV7_PMU_CORTEX_A8_NAME;
2109                         memcpy(armpmu_perf_cache_map, armv7_a8_perf_cache_map,
2110                                 sizeof(armv7_a8_perf_cache_map));
2111                         armv7pmu.event_map = armv7_a8_pmu_event_map;
2112                         armpmu = &armv7pmu;
2113
2114                         /* Reset PMNC and read the nb of CNTx counters
2115                             supported */
2116                         armv7pmu.num_events = armv7_reset_read_pmnc();
2117                         perf_max_events = armv7pmu.num_events;
2118                         break;
2119                 case 0xC090:    /* Cortex-A9 */
2120                         armv7pmu.name = ARMV7_PMU_CORTEX_A9_NAME;
2121                         memcpy(armpmu_perf_cache_map, armv7_a9_perf_cache_map,
2122                                 sizeof(armv7_a9_perf_cache_map));
2123                         armv7pmu.event_map = armv7_a9_pmu_event_map;
2124                         armpmu = &armv7pmu;
2125
2126                         /* Reset PMNC and read the nb of CNTx counters
2127                             supported */
2128                         armv7pmu.num_events = armv7_reset_read_pmnc();
2129                         perf_max_events = armv7pmu.num_events;
2130                         break;
2131                 default:
2132                         pr_info("no hardware support available\n");
2133                         perf_max_events = -1;
2134                 }
2135         }
2136
2137         if (armpmu)
2138                 pr_info("enabled with %s PMU driver, %d counters available\n",
2139                         armpmu->name, armpmu->num_events);
2140
2141         return 0;
2142 }
2143 arch_initcall(init_hw_perf_events);
2144
2145 /*
2146  * Callchain handling code.
2147  */
2148 static inline void
2149 callchain_store(struct perf_callchain_entry *entry,
2150                 u64 ip)
2151 {
2152         if (entry->nr < PERF_MAX_STACK_DEPTH)
2153                 entry->ip[entry->nr++] = ip;
2154 }
2155
2156 /*
2157  * The registers we're interested in are at the end of the variable
2158  * length saved register structure. The fp points at the end of this
2159  * structure so the address of this struct is:
2160  * (struct frame_tail *)(xxx->fp)-1
2161  *
2162  * This code has been adapted from the ARM OProfile support.
2163  */
2164 struct frame_tail {
2165         struct frame_tail   *fp;
2166         unsigned long       sp;
2167         unsigned long       lr;
2168 } __attribute__((packed));
2169
2170 /*
2171  * Get the return address for a single stackframe and return a pointer to the
2172  * next frame tail.
2173  */
2174 static struct frame_tail *
2175 user_backtrace(struct frame_tail *tail,
2176                struct perf_callchain_entry *entry)
2177 {
2178         struct frame_tail buftail;
2179
2180         /* Also check accessibility of one struct frame_tail beyond */
2181         if (!access_ok(VERIFY_READ, tail, sizeof(buftail)))
2182                 return NULL;
2183         if (__copy_from_user_inatomic(&buftail, tail, sizeof(buftail)))
2184                 return NULL;
2185
2186         callchain_store(entry, buftail.lr);
2187
2188         /*
2189          * Frame pointers should strictly progress back up the stack
2190          * (towards higher addresses).
2191          */
2192         if (tail >= buftail.fp)
2193                 return NULL;
2194
2195         return buftail.fp - 1;
2196 }
2197
2198 static void
2199 perf_callchain_user(struct pt_regs *regs,
2200                     struct perf_callchain_entry *entry)
2201 {
2202         struct frame_tail *tail;
2203
2204         callchain_store(entry, PERF_CONTEXT_USER);
2205
2206         if (!user_mode(regs))
2207                 regs = task_pt_regs(current);
2208
2209         tail = (struct frame_tail *)regs->ARM_fp - 1;
2210
2211         while (tail && !((unsigned long)tail & 0x3))
2212                 tail = user_backtrace(tail, entry);
2213 }
2214
2215 /*
2216  * Gets called by walk_stackframe() for every stackframe. This will be called
2217  * whist unwinding the stackframe and is like a subroutine return so we use
2218  * the PC.
2219  */
2220 static int
2221 callchain_trace(struct stackframe *fr,
2222                 void *data)
2223 {
2224         struct perf_callchain_entry *entry = data;
2225         callchain_store(entry, fr->pc);
2226         return 0;
2227 }
2228
2229 static void
2230 perf_callchain_kernel(struct pt_regs *regs,
2231                       struct perf_callchain_entry *entry)
2232 {
2233         struct stackframe fr;
2234
2235         callchain_store(entry, PERF_CONTEXT_KERNEL);
2236         fr.fp = regs->ARM_fp;
2237         fr.sp = regs->ARM_sp;
2238         fr.lr = regs->ARM_lr;
2239         fr.pc = regs->ARM_pc;
2240         walk_stackframe(&fr, callchain_trace, entry);
2241 }
2242
2243 static void
2244 perf_do_callchain(struct pt_regs *regs,
2245                   struct perf_callchain_entry *entry)
2246 {
2247         int is_user;
2248
2249         if (!regs)
2250                 return;
2251
2252         is_user = user_mode(regs);
2253
2254         if (!current || !current->pid)
2255                 return;
2256
2257         if (is_user && current->state != TASK_RUNNING)
2258                 return;
2259
2260         if (!is_user)
2261                 perf_callchain_kernel(regs, entry);
2262
2263         if (current->mm)
2264                 perf_callchain_user(regs, entry);
2265 }
2266
2267 static DEFINE_PER_CPU(struct perf_callchain_entry, pmc_irq_entry);
2268
2269 struct perf_callchain_entry *
2270 perf_callchain(struct pt_regs *regs)
2271 {
2272         struct perf_callchain_entry *entry = &__get_cpu_var(pmc_irq_entry);
2273
2274         entry->nr = 0;
2275         perf_do_callchain(regs, entry);
2276         return entry;
2277 }