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, "armpmu", NULL);
 336                 if (err) {
 337                         pr_warning("unable to request IRQ%d for ARM "
 338                                    "perf counters\n", pmu_irqs->irqs[i]);
 339                         break;
 340                 }
 341         }
 342
 343         if (err) {
 344                 for (i = i - 1; i >= 0; --i)
 345                         free_irq(pmu_irqs->irqs[i], NULL);
 346                 release_pmu(pmu_irqs);
 347                 pmu_irqs = NULL;
 348         }
 349
 350         return err;
 351 }
 352
 353 static void
 354 armpmu_release_hardware(void)
 355 {
 356         int i;
 357
 358         for (i = pmu_irqs->num_irqs - 1; i >= 0; --i)
 359                 free_irq(pmu_irqs->irqs[i], NULL);
 360         armpmu->stop();
 361
 362         release_pmu(pmu_irqs);
 363         pmu_irqs = NULL;
 364 }
 365
 366 static atomic_t active_events = ATOMIC_INIT(0);
 367 static DEFINE_MUTEX(pmu_reserve_mutex);
 368
 369 static void
 370 hw_perf_event_destroy(struct perf_event *event)
 371 {
 372         if (atomic_dec_and_mutex_lock(&active_events, &pmu_reserve_mutex)) {
 373                 armpmu_release_hardware();
 374                 mutex_unlock(&pmu_reserve_mutex);
 375         }
 376 }
 377
 378 static int
 379 __hw_perf_event_init(struct perf_event *event)
 380 {
 381         struct hw_perf_event *hwc = &event->hw;
 382         int mapping, err;
 383
 384         /* Decode the generic type into an ARM event identifier. */
 385         if (PERF_TYPE_HARDWARE == event->attr.type) {
 386                 mapping = armpmu->event_map(event->attr.config);
 387         } else if (PERF_TYPE_HW_CACHE == event->attr.type) {
 388                 mapping = armpmu_map_cache_event(event->attr.config);
 389         } else if (PERF_TYPE_RAW == event->attr.type) {
 390                 mapping = armpmu->raw_event(event->attr.config);
 391         } else {
 392                 pr_debug("event type %x not supported\n", event->attr.type);
 393                 return -EOPNOTSUPP;
 394         }
 395
 396         if (mapping < 0) {
 397                 pr_debug("event %x:%llx not supported\n", event->attr.type,
 398                          event->attr.config);
 399                 return mapping;
 400         }
 401
 402         /*
 403          * Check whether we need to exclude the counter from certain modes.
 404          * The ARM performance counters are on all of the time so if someone
 405          * has asked us for some excludes then we have to fail.
 406          */
 407         if (event->attr.exclude_kernel || event->attr.exclude_user ||
 408             event->attr.exclude_hv || event->attr.exclude_idle) {
 409                 pr_debug("ARM performance counters do not support "
 410                          "mode exclusion\n");
 411                 return -EPERM;
 412         }
 413
 414         /*
 415          * We don't assign an index until we actually place the event onto
 416          * hardware. Use -1 to signify that we haven't decided where to put it
 417          * yet. For SMP systems, each core has it's own PMU so we can't do any
 418          * clever allocation or constraints checking at this point.
 419          */
 420         hwc->idx = -1;
 421
 422         /*
 423          * Store the event encoding into the config_base field. config and
 424          * event_base are unused as the only 2 things we need to know are
 425          * the event mapping and the counter to use. The counter to use is
 426          * also the indx and the config_base is the event type.
 427          */
 428         hwc->config_base            = (unsigned long)mapping;
 429         hwc->config                 = 0;
 430         hwc->event_base             = 0;
 431
 432         if (!hwc->sample_period) {
 433                 hwc->sample_period  = armpmu->max_period;
 434                 hwc->last_period    = hwc->sample_period;
 435                 atomic64_set(&hwc->period_left, hwc->sample_period);
 436         }
 437
 438         err = 0;
 439         if (event->group_leader != event) {
 440                 err = validate_group(event);
 441                 if (err)
 442                         return -EINVAL;
 443         }
 444
 445         return err;
 446 }
 447
 448 const struct pmu *
 449 hw_perf_event_init(struct perf_event *event)
 450 {
 451         int err = 0;
 452
 453         if (!armpmu)
 454                 return ERR_PTR(-ENODEV);
 455
 456         event->destroy = hw_perf_event_destroy;
 457
 458         if (!atomic_inc_not_zero(&active_events)) {
 459                 if (atomic_read(&active_events) > perf_max_events) {
 460                         atomic_dec(&active_events);
 461                         return ERR_PTR(-ENOSPC);
 462                 }
 463
 464                 mutex_lock(&pmu_reserve_mutex);
 465                 if (atomic_read(&active_events) == 0) {
 466                         err = armpmu_reserve_hardware();
 467                 }
 468
 469                 if (!err)
 470                         atomic_inc(&active_events);
 471                 mutex_unlock(&pmu_reserve_mutex);
 472         }
 473
 474         if (err)
 475                 return ERR_PTR(err);
 476
 477         err = __hw_perf_event_init(event);
 478         if (err)
 479                 hw_perf_event_destroy(event);
 480
 481         return err ? ERR_PTR(err) : &pmu;
 482 }
 483
 484 void
 485 hw_perf_enable(void)
 486 {
 487         /* Enable all of the perf events on hardware. */
 488         int idx;
 489         struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
 490
 491         if (!armpmu)
 492                 return;
 493
 494         for (idx = 0; idx <= armpmu->num_events; ++idx) {
 495                 struct perf_event *event = cpuc->events[idx];
 496
 497                 if (!event)
 498                         continue;
 499
 500                 armpmu->enable(&event->hw, idx);
 501         }
 502
 503         armpmu->start();
 504 }
 505
 506 void
 507 hw_perf_disable(void)
 508 {
 509         if (armpmu)
 510                 armpmu->stop();
 511 }
 512
 513 /*
 514  * ARMv6 Performance counter handling code.
 515  *
 516  * ARMv6 has 2 configurable performance counters and a single cycle counter.
 517  * They all share a single reset bit but can be written to zero so we can use
 518  * that for a reset.
 519  *
 520  * The counters can't be individually enabled or disabled so when we remove
 521  * one event and replace it with another we could get spurious counts from the
 522  * wrong event. However, we can take advantage of the fact that the
 523  * performance counters can export events to the event bus, and the event bus
 524  * itself can be monitored. This requires that we *don't* export the events to
 525  * the event bus. The procedure for disabling a configurable counter is:
 526  *      - change the counter to count the ETMEXTOUT[0] signal (0x20). This
 527  *        effectively stops the counter from counting.
 528  *      - disable the counter's interrupt generation (each counter has it's
 529  *        own interrupt enable bit).
 530  * Once stopped, the counter value can be written as 0 to reset.
 531  *
 532  * To enable a counter:
 533  *      - enable the counter's interrupt generation.
 534  *      - set the new event type.
 535  *
 536  * Note: the dedicated cycle counter only counts cycles and can't be
 537  * enabled/disabled independently of the others. When we want to disable the
 538  * cycle counter, we have to just disable the interrupt reporting and start
 539  * ignoring that counter. When re-enabling, we have to reset the value and
 540  * enable the interrupt.
 541  */
 542
 543 enum armv6_perf_types {
 544         ARMV6_PERFCTR_ICACHE_MISS           = 0x0,
 545         ARMV6_PERFCTR_IBUF_STALL            = 0x1,
 546         ARMV6_PERFCTR_DDEP_STALL            = 0x2,
 547         ARMV6_PERFCTR_ITLB_MISS             = 0x3,
 548         ARMV6_PERFCTR_DTLB_MISS             = 0x4,
 549         ARMV6_PERFCTR_BR_EXEC               = 0x5,
 550         ARMV6_PERFCTR_BR_MISPREDICT         = 0x6,
 551         ARMV6_PERFCTR_INSTR_EXEC            = 0x7,
 552         ARMV6_PERFCTR_DCACHE_HIT            = 0x9,
 553         ARMV6_PERFCTR_DCACHE_ACCESS         = 0xA,
 554         ARMV6_PERFCTR_DCACHE_MISS           = 0xB,
 555         ARMV6_PERFCTR_DCACHE_WBACK          = 0xC,
 556         ARMV6_PERFCTR_SW_PC_CHANGE          = 0xD,
 557         ARMV6_PERFCTR_MAIN_TLB_MISS         = 0xF,
 558         ARMV6_PERFCTR_EXPL_D_ACCESS         = 0x10,
 559         ARMV6_PERFCTR_LSU_FULL_STALL        = 0x11,
 560         ARMV6_PERFCTR_WBUF_DRAINED          = 0x12,
 561         ARMV6_PERFCTR_CPU_CYCLES            = 0xFF,
 562         ARMV6_PERFCTR_NOP                   = 0x20,
 563 };
 564
 565 enum armv6_counters {
 566         ARMV6_CYCLE_COUNTER = 1,
 567         ARMV6_COUNTER0,
 568         ARMV6_COUNTER1,
 569 };
 570
 571 /*
 572  * The hardware events that we support. We do support cache operations but
 573  * we have harvard caches and no way to combine instruction and data
 574  * accesses/misses in hardware.
 575  */
 576 static const unsigned armv6_perf_map[PERF_COUNT_HW_MAX] = {
 577         [PERF_COUNT_HW_CPU_CYCLES]          = ARMV6_PERFCTR_CPU_CYCLES,
 578         [PERF_COUNT_HW_INSTRUCTIONS]        = ARMV6_PERFCTR_INSTR_EXEC,
 579         [PERF_COUNT_HW_CACHE_REFERENCES]    = HW_OP_UNSUPPORTED,
 580         [PERF_COUNT_HW_CACHE_MISSES]        = HW_OP_UNSUPPORTED,
 581         [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = ARMV6_PERFCTR_BR_EXEC,
 582         [PERF_COUNT_HW_BRANCH_MISSES]       = ARMV6_PERFCTR_BR_MISPREDICT,
 583         [PERF_COUNT_HW_BUS_CYCLES]          = HW_OP_UNSUPPORTED,
 584 };
 585
 586 static const unsigned armv6_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
 587                                           [PERF_COUNT_HW_CACHE_OP_MAX]
 588                                           [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
 589         [C(L1D)] = {
 590                 /*
 591                  * The performance counters don't differentiate between read
 592                  * and write accesses/misses so this isn't strictly correct,
 593                  * but it's the best we can do. Writes and reads get
 594                  * combined.
 595                  */
 596                 [C(OP_READ)] = {
 597                         [C(RESULT_ACCESS)]      = ARMV6_PERFCTR_DCACHE_ACCESS,
 598                         [C(RESULT_MISS)]        = ARMV6_PERFCTR_DCACHE_MISS,
 599                 },
 600                 [C(OP_WRITE)] = {
 601                         [C(RESULT_ACCESS)]      = ARMV6_PERFCTR_DCACHE_ACCESS,
 602                         [C(RESULT_MISS)]        = ARMV6_PERFCTR_DCACHE_MISS,
 603                 },
 604                 [C(OP_PREFETCH)] = {
 605                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 606                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
 607                 },
 608         },
 609         [C(L1I)] = {
 610                 [C(OP_READ)] = {
 611                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 612                         [C(RESULT_MISS)]        = ARMV6_PERFCTR_ICACHE_MISS,
 613                 },
 614                 [C(OP_WRITE)] = {
 615                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 616                         [C(RESULT_MISS)]        = ARMV6_PERFCTR_ICACHE_MISS,
 617                 },
 618                 [C(OP_PREFETCH)] = {
 619                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 620                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
 621                 },
 622         },
 623         [C(LL)] = {
 624                 [C(OP_READ)] = {
 625                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 626                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
 627                 },
 628                 [C(OP_WRITE)] = {
 629                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 630                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
 631                 },
 632                 [C(OP_PREFETCH)] = {
 633                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 634                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
 635                 },
 636         },
 637         [C(DTLB)] = {
 638                 /*
 639                  * The ARM performance counters can count micro DTLB misses,
 640                  * micro ITLB misses and main TLB misses. There isn't an event
 641                  * for TLB misses, so use the micro misses here and if users
 642                  * want the main TLB misses they can use a raw counter.
 643                  */
 644                 [C(OP_READ)] = {
 645                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 646                         [C(RESULT_MISS)]        = ARMV6_PERFCTR_DTLB_MISS,
 647                 },
 648                 [C(OP_WRITE)] = {
 649                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 650                         [C(RESULT_MISS)]        = ARMV6_PERFCTR_DTLB_MISS,
 651                 },
 652                 [C(OP_PREFETCH)] = {
 653                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 654                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
 655                 },
 656         },
 657         [C(ITLB)] = {
 658                 [C(OP_READ)] = {
 659                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 660                         [C(RESULT_MISS)]        = ARMV6_PERFCTR_ITLB_MISS,
 661                 },
 662                 [C(OP_WRITE)] = {
 663                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 664                         [C(RESULT_MISS)]        = ARMV6_PERFCTR_ITLB_MISS,
 665                 },
 666                 [C(OP_PREFETCH)] = {
 667                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 668                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
 669                 },
 670         },
 671         [C(BPU)] = {
 672                 [C(OP_READ)] = {
 673                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 674                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
 675                 },
 676                 [C(OP_WRITE)] = {
 677                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 678                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
 679                 },
 680                 [C(OP_PREFETCH)] = {
 681                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
 682                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
 683                 },
 684         },
 685 };
 686
 687 enum armv6mpcore_perf_types {
 688         ARMV6MPCORE_PERFCTR_ICACHE_MISS     = 0x0,
 689         ARMV6MPCORE_PERFCTR_IBUF_STALL      = 0x1,
 690         ARMV6MPCORE_PERFCTR_DDEP_STALL      = 0x2,
 691         ARMV6MPCORE_PERFCTR_ITLB_MISS       = 0x3,
 692         ARMV6MPCORE_PERFCTR_DTLB_MISS       = 0x4,
 693         ARMV6MPCORE_PERFCTR_BR_EXEC         = 0x5,
 694         ARMV6MPCORE_PERFCTR_BR_NOTPREDICT   = 0x6,
 695         ARMV6MPCORE_PERFCTR_BR_MISPREDICT   = 0x7,
 696         ARMV6MPCORE_PERFCTR_INSTR_EXEC      = 0x8,
 697         ARMV6MPCORE_PERFCTR_DCACHE_RDACCESS = 0xA,
 698         ARMV6MPCORE_PERFCTR_DCACHE_RDMISS   = 0xB,
 699         ARMV6MPCORE_PERFCTR_DCACHE_WRACCESS = 0xC,
 700         ARMV6MPCORE_PERFCTR_DCACHE_WRMISS   = 0xD,
 701         ARMV6MPCORE_PERFCTR_DCACHE_EVICTION = 0xE,
 702         ARMV6MPCORE_PERFCTR_SW_PC_CHANGE    = 0xF,
 703         ARMV6MPCORE_PERFCTR_MAIN_TLB_MISS   = 0x10,
 704         ARMV6MPCORE_PERFCTR_EXPL_MEM_ACCESS = 0x11,
 705         ARMV6MPCORE_PERFCTR_LSU_FULL_STALL  = 0x12,
 706         ARMV6MPCORE_PERFCTR_WBUF_DRAINED    = 0x13,
 707         ARMV6MPCORE_PERFCTR_CPU_CYCLES      = 0xFF,
 708 };
 709
 710 /*
 711  * The hardware events that we support. We do support cache operations but
 712  * we have harvard caches and no way to combine instruction and data
 713  * accesses/misses in hardware.
 714  */
 715 static const unsigned armv6mpcore_perf_map[PERF_COUNT_HW_MAX] = {
 716         [PERF_COUNT_HW_CPU_CYCLES]          = ARMV6MPCORE_PERFCTR_CPU_CYCLES,
 717         [PERF_COUNT_HW_INSTRUCTIONS]        = ARMV6MPCORE_PERFCTR_INSTR_EXEC,
 718         [PERF_COUNT_HW_CACHE_REFERENCES]    = HW_OP_UNSUPPORTED,
 719         [PERF_COUNT_HW_CACHE_MISSES]        = HW_OP_UNSUPPORTED,
 720         [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = ARMV6MPCORE_PERFCTR_BR_EXEC,
 721         [PERF_COUNT_HW_BRANCH_MISSES]       = ARMV6MPCORE_PERFCTR_BR_MISPREDICT,
 722         [PERF_COUNT_HW_BUS_CYCLES]          = HW_OP_UNSUPPORTED,
 723 };
 724
 725 static const unsigned armv6mpcore_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
 726                                         [PERF_COUNT_HW_CACHE_OP_MAX]
 727                                         [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
 728         [C(L1D)] = {
 729                 [C(OP_READ)] = {
 730                         [C(RESULT_ACCESS)]  =
 731                                 ARMV6MPCORE_PERFCTR_DCACHE_RDACCESS,
 732                         [C(RESULT_MISS)]    =
 733                                 ARMV6MPCORE_PERFCTR_DCACHE_RDMISS,
 734                 },
 735                 [C(OP_WRITE)] = {
 736                         [C(RESULT_ACCESS)]  =
 737                                 ARMV6MPCORE_PERFCTR_DCACHE_WRACCESS,
 738                         [C(RESULT_MISS)]    =
 739                                 ARMV6MPCORE_PERFCTR_DCACHE_WRMISS,
 740                 },
 741                 [C(OP_PREFETCH)] = {
 742                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 743                         [C(RESULT_MISS)]    = CACHE_OP_UNSUPPORTED,
 744                 },
 745         },
 746         [C(L1I)] = {
 747                 [C(OP_READ)] = {
 748                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 749                         [C(RESULT_MISS)]    = ARMV6MPCORE_PERFCTR_ICACHE_MISS,
 750                 },
 751                 [C(OP_WRITE)] = {
 752                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 753                         [C(RESULT_MISS)]    = ARMV6MPCORE_PERFCTR_ICACHE_MISS,
 754                 },
 755                 [C(OP_PREFETCH)] = {
 756                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 757                         [C(RESULT_MISS)]    = CACHE_OP_UNSUPPORTED,
 758                 },
 759         },
 760         [C(LL)] = {
 761                 [C(OP_READ)] = {
 762                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 763                         [C(RESULT_MISS)]    = CACHE_OP_UNSUPPORTED,
 764                 },
 765                 [C(OP_WRITE)] = {
 766                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 767                         [C(RESULT_MISS)]    = CACHE_OP_UNSUPPORTED,
 768                 },
 769                 [C(OP_PREFETCH)] = {
 770                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 771                         [C(RESULT_MISS)]    = CACHE_OP_UNSUPPORTED,
 772                 },
 773         },
 774         [C(DTLB)] = {
 775                 /*
 776                  * The ARM performance counters can count micro DTLB misses,
 777                  * micro ITLB misses and main TLB misses. There isn't an event
 778                  * for TLB misses, so use the micro misses here and if users
 779                  * want the main TLB misses they can use a raw counter.
 780                  */
 781                 [C(OP_READ)] = {
 782                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 783                         [C(RESULT_MISS)]    = ARMV6MPCORE_PERFCTR_DTLB_MISS,
 784                 },
 785                 [C(OP_WRITE)] = {
 786                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 787                         [C(RESULT_MISS)]    = ARMV6MPCORE_PERFCTR_DTLB_MISS,
 788                 },
 789                 [C(OP_PREFETCH)] = {
 790                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 791                         [C(RESULT_MISS)]    = CACHE_OP_UNSUPPORTED,
 792                 },
 793         },
 794         [C(ITLB)] = {
 795                 [C(OP_READ)] = {
 796                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 797                         [C(RESULT_MISS)]    = ARMV6MPCORE_PERFCTR_ITLB_MISS,
 798                 },
 799                 [C(OP_WRITE)] = {
 800                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 801                         [C(RESULT_MISS)]    = ARMV6MPCORE_PERFCTR_ITLB_MISS,
 802                 },
 803                 [C(OP_PREFETCH)] = {
 804                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 805                         [C(RESULT_MISS)]    = CACHE_OP_UNSUPPORTED,
 806                 },
 807         },
 808         [C(BPU)] = {
 809                 [C(OP_READ)] = {
 810                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 811                         [C(RESULT_MISS)]    = CACHE_OP_UNSUPPORTED,
 812                 },
 813                 [C(OP_WRITE)] = {
 814                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 815                         [C(RESULT_MISS)]    = CACHE_OP_UNSUPPORTED,
 816                 },
 817                 [C(OP_PREFETCH)] = {
 818                         [C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
 819                         [C(RESULT_MISS)]    = CACHE_OP_UNSUPPORTED,
 820                 },
 821         },
 822 };
 823
 824 static inline unsigned long
 825 armv6_pmcr_read(void)
 826 {
 827         u32 val;
 828         asm volatile("mrc   p15, 0, %0, c15, c12, 0" : "=r"(val));
 829         return val;
 830 }
 831
 832 static inline void
 833 armv6_pmcr_write(unsigned long val)
 834 {
 835         asm volatile("mcr   p15, 0, %0, c15, c12, 0" : : "r"(val));
 836 }
 837
 838 #define ARMV6_PMCR_ENABLE               (1 << 0)
 839 #define ARMV6_PMCR_CTR01_RESET          (1 << 1)
 840 #define ARMV6_PMCR_CCOUNT_RESET         (1 << 2)
 841 #define ARMV6_PMCR_CCOUNT_DIV           (1 << 3)
 842 #define ARMV6_PMCR_COUNT0_IEN           (1 << 4)
 843 #define ARMV6_PMCR_COUNT1_IEN           (1 << 5)
 844 #define ARMV6_PMCR_CCOUNT_IEN           (1 << 6)
 845 #define ARMV6_PMCR_COUNT0_OVERFLOW      (1 << 8)
 846 #define ARMV6_PMCR_COUNT1_OVERFLOW      (1 << 9)
 847 #define ARMV6_PMCR_CCOUNT_OVERFLOW      (1 << 10)
 848 #define ARMV6_PMCR_EVT_COUNT0_SHIFT     20
 849 #define ARMV6_PMCR_EVT_COUNT0_MASK      (0xFF << ARMV6_PMCR_EVT_COUNT0_SHIFT)
 850 #define ARMV6_PMCR_EVT_COUNT1_SHIFT     12
 851 #define ARMV6_PMCR_EVT_COUNT1_MASK      (0xFF << ARMV6_PMCR_EVT_COUNT1_SHIFT)
 852
 853 #define ARMV6_PMCR_OVERFLOWED_MASK \
 854         (ARMV6_PMCR_COUNT0_OVERFLOW | ARMV6_PMCR_COUNT1_OVERFLOW | \
 855          ARMV6_PMCR_CCOUNT_OVERFLOW)
 856
 857 static inline int
 858 armv6_pmcr_has_overflowed(unsigned long pmcr)
 859 {
 860         return (pmcr & ARMV6_PMCR_OVERFLOWED_MASK);
 861 }
 862
 863 static inline int
 864 armv6_pmcr_counter_has_overflowed(unsigned long pmcr,
 865                                   enum armv6_counters counter)
 866 {
 867         int ret = 0;
 868
 869         if (ARMV6_CYCLE_COUNTER == counter)
 870                 ret = pmcr & ARMV6_PMCR_CCOUNT_OVERFLOW;
 871         else if (ARMV6_COUNTER0 == counter)
 872                 ret = pmcr & ARMV6_PMCR_COUNT0_OVERFLOW;
 873         else if (ARMV6_COUNTER1 == counter)
 874                 ret = pmcr & ARMV6_PMCR_COUNT1_OVERFLOW;
 875         else
 876                 WARN_ONCE(1, "invalid counter number (%d)\n", counter);
 877
 878         return ret;
 879 }
 880
 881 static inline u32
 882 armv6pmu_read_counter(int counter)
 883 {
 884         unsigned long value = 0;
 885
 886         if (ARMV6_CYCLE_COUNTER == counter)
 887                 asm volatile("mrc   p15, 0, %0, c15, c12, 1" : "=r"(value));
 888         else if (ARMV6_COUNTER0 == counter)
 889                 asm volatile("mrc   p15, 0, %0, c15, c12, 2" : "=r"(value));
 890         else if (ARMV6_COUNTER1 == counter)
 891                 asm volatile("mrc   p15, 0, %0, c15, c12, 3" : "=r"(value));
 892         else
 893                 WARN_ONCE(1, "invalid counter number (%d)\n", counter);
 894
 895         return value;
 896 }
 897
 898 static inline void
 899 armv6pmu_write_counter(int counter,
 900                        u32 value)
 901 {
 902         if (ARMV6_CYCLE_COUNTER == counter)
 903                 asm volatile("mcr   p15, 0, %0, c15, c12, 1" : : "r"(value));
 904         else if (ARMV6_COUNTER0 == counter)
 905                 asm volatile("mcr   p15, 0, %0, c15, c12, 2" : : "r"(value));
 906         else if (ARMV6_COUNTER1 == counter)
 907                 asm volatile("mcr   p15, 0, %0, c15, c12, 3" : : "r"(value));
 908         else
 909                 WARN_ONCE(1, "invalid counter number (%d)\n", counter);
 910 }
 911
 912 void
 913 armv6pmu_enable_event(struct hw_perf_event *hwc,
 914                       int idx)
 915 {
 916         unsigned long val, mask, evt, flags;
 917
 918         if (ARMV6_CYCLE_COUNTER == idx) {
 919                 mask    = 0;
 920                 evt     = ARMV6_PMCR_CCOUNT_IEN;
 921         } else if (ARMV6_COUNTER0 == idx) {
 922                 mask    = ARMV6_PMCR_EVT_COUNT0_MASK;
 923                 evt     = (hwc->config_base << ARMV6_PMCR_EVT_COUNT0_SHIFT) |
 924                           ARMV6_PMCR_COUNT0_IEN;
 925         } else if (ARMV6_COUNTER1 == idx) {
 926                 mask    = ARMV6_PMCR_EVT_COUNT1_MASK;
 927                 evt     = (hwc->config_base << ARMV6_PMCR_EVT_COUNT1_SHIFT) |
 928                           ARMV6_PMCR_COUNT1_IEN;
 929         } else {
 930                 WARN_ONCE(1, "invalid counter number (%d)\n", idx);
 931                 return;
 932         }
 933
 934         /*
 935          * Mask out the current event and set the counter to count the event
 936          * that we're interested in.
 937          */
 938         spin_lock_irqsave(&pmu_lock, flags);
 939         val = armv6_pmcr_read();
 940         val &= ~mask;
 941         val |= evt;
 942         armv6_pmcr_write(val);
 943         spin_unlock_irqrestore(&pmu_lock, flags);
 944 }
 945
 946 static irqreturn_t
 947 armv6pmu_handle_irq(int irq_num,
 948                     void *dev)
 949 {
 950         unsigned long pmcr = armv6_pmcr_read();
 951         struct perf_sample_data data;
 952         struct cpu_hw_events *cpuc;
 953         struct pt_regs *regs;
 954         int idx;
 955
 956         if (!armv6_pmcr_has_overflowed(pmcr))
 957                 return IRQ_NONE;
 958
 959         regs = get_irq_regs();
 960
 961         /*
 962          * The interrupts are cleared by writing the overflow flags back to
 963          * the control register. All of the other bits don't have any effect
 964          * if they are rewritten, so write the whole value back.
 965          */
 966         armv6_pmcr_write(pmcr);
 967
 968         data.addr = 0;
 969
 970         cpuc = &__get_cpu_var(cpu_hw_events);
 971         for (idx = 0; idx <= armpmu->num_events; ++idx) {
 972                 struct perf_event *event = cpuc->events[idx];
 973                 struct hw_perf_event *hwc;
 974
 975                 if (!test_bit(idx, cpuc->active_mask))
 976                         continue;
 977
 978                 /*
 979                  * We have a single interrupt for all counters. Check that
 980                  * each counter has overflowed before we process it.
 981                  */
 982                 if (!armv6_pmcr_counter_has_overflowed(pmcr, idx))
 983                         continue;
 984
 985                 hwc = &event->hw;
 986                 armpmu_event_update(event, hwc, idx);
 987                 data.period = event->hw.last_period;
 988                 if (!armpmu_event_set_period(event, hwc, idx))
 989                         continue;
 990
 991                 if (perf_event_overflow(event, 0, &data, regs))
 992                         armpmu->disable(hwc, idx);
 993         }
 994
 995         /*
 996          * Handle the pending perf events.
 997          *
 998          * Note: this call *must* be run with interrupts enabled. For
 999          * platforms that can have the PMU interrupts raised as a PMI, this
1000          * will not work.
1001          */
1002         perf_event_do_pending();
1003
1004         return IRQ_HANDLED;
1005 }
1006
1007 static void
1008 armv6pmu_start(void)
1009 {
1010         unsigned long flags, val;
1011
1012         spin_lock_irqsave(&pmu_lock, flags);
1013         val = armv6_pmcr_read();
1014         val |= ARMV6_PMCR_ENABLE;
1015         armv6_pmcr_write(val);
1016         spin_unlock_irqrestore(&pmu_lock, flags);
1017 }
1018
1019 void
1020 armv6pmu_stop(void)
1021 {
1022         unsigned long flags, val;
1023
1024         spin_lock_irqsave(&pmu_lock, flags);
1025         val = armv6_pmcr_read();
1026         val &= ~ARMV6_PMCR_ENABLE;
1027         armv6_pmcr_write(val);
1028         spin_unlock_irqrestore(&pmu_lock, flags);
1029 }
1030
1031 static inline int
1032 armv6pmu_event_map(int config)
1033 {
1034         int mapping = armv6_perf_map[config];
1035         if (HW_OP_UNSUPPORTED == mapping)
1036                 mapping = -EOPNOTSUPP;
1037         return mapping;
1038 }
1039
1040 static inline int
1041 armv6mpcore_pmu_event_map(int config)
1042 {
1043         int mapping = armv6mpcore_perf_map[config];
1044         if (HW_OP_UNSUPPORTED == mapping)
1045                 mapping = -EOPNOTSUPP;
1046         return mapping;
1047 }
1048
1049 static u64
1050 armv6pmu_raw_event(u64 config)
1051 {
1052         return config & 0xff;
1053 }
1054
1055 static int
1056 armv6pmu_get_event_idx(struct cpu_hw_events *cpuc,
1057                        struct hw_perf_event *event)
1058 {
1059         /* Always place a cycle counter into the cycle counter. */
1060         if (ARMV6_PERFCTR_CPU_CYCLES == event->config_base) {
1061                 if (test_and_set_bit(ARMV6_CYCLE_COUNTER, cpuc->used_mask))
1062                         return -EAGAIN;
1063
1064                 return ARMV6_CYCLE_COUNTER;
1065         } else {
1066                 /*
1067                  * For anything other than a cycle counter, try and use
1068                  * counter0 and counter1.
1069                  */
1070                 if (!test_and_set_bit(ARMV6_COUNTER1, cpuc->used_mask)) {
1071                         return ARMV6_COUNTER1;
1072                 }
1073
1074                 if (!test_and_set_bit(ARMV6_COUNTER0, cpuc->used_mask)) {
1075                         return ARMV6_COUNTER0;
1076                 }
1077
1078                 /* The counters are all in use. */
1079                 return -EAGAIN;
1080         }
1081 }
1082
1083 static void
1084 armv6pmu_disable_event(struct hw_perf_event *hwc,
1085                        int idx)
1086 {
1087         unsigned long val, mask, evt, flags;
1088
1089         if (ARMV6_CYCLE_COUNTER == idx) {
1090                 mask    = ARMV6_PMCR_CCOUNT_IEN;
1091                 evt     = 0;
1092         } else if (ARMV6_COUNTER0 == idx) {
1093                 mask    = ARMV6_PMCR_COUNT0_IEN | ARMV6_PMCR_EVT_COUNT0_MASK;
1094                 evt     = ARMV6_PERFCTR_NOP << ARMV6_PMCR_EVT_COUNT0_SHIFT;
1095         } else if (ARMV6_COUNTER1 == idx) {
1096                 mask    = ARMV6_PMCR_COUNT1_IEN | ARMV6_PMCR_EVT_COUNT1_MASK;
1097                 evt     = ARMV6_PERFCTR_NOP << ARMV6_PMCR_EVT_COUNT1_SHIFT;
1098         } else {
1099                 WARN_ONCE(1, "invalid counter number (%d)\n", idx);
1100                 return;
1101         }
1102
1103         /*
1104          * Mask out the current event and set the counter to count the number
1105          * of ETM bus signal assertion cycles. The external reporting should
1106          * be disabled and so this should never increment.
1107          */
1108         spin_lock_irqsave(&pmu_lock, flags);
1109         val = armv6_pmcr_read();
1110         val &= ~mask;
1111         val |= evt;
1112         armv6_pmcr_write(val);
1113         spin_unlock_irqrestore(&pmu_lock, flags);
1114 }
1115
1116 static void
1117 armv6mpcore_pmu_disable_event(struct hw_perf_event *hwc,
1118                               int idx)
1119 {
1120         unsigned long val, mask, flags, evt = 0;
1121
1122         if (ARMV6_CYCLE_COUNTER == idx) {
1123                 mask    = ARMV6_PMCR_CCOUNT_IEN;
1124         } else if (ARMV6_COUNTER0 == idx) {
1125                 mask    = ARMV6_PMCR_COUNT0_IEN;
1126         } else if (ARMV6_COUNTER1 == idx) {
1127                 mask    = ARMV6_PMCR_COUNT1_IEN;
1128         } else {
1129                 WARN_ONCE(1, "invalid counter number (%d)\n", idx);
1130                 return;
1131         }
1132
1133         /*
1134          * Unlike UP ARMv6, we don't have a way of stopping the counters. We
1135          * simply disable the interrupt reporting.
1136          */
1137         spin_lock_irqsave(&pmu_lock, flags);
1138         val = armv6_pmcr_read();
1139         val &= ~mask;
1140         val |= evt;
1141         armv6_pmcr_write(val);
1142         spin_unlock_irqrestore(&pmu_lock, flags);
1143 }
1144
1145 static const struct arm_pmu armv6pmu = {
1146         .name                   = "v6",
1147         .handle_irq             = armv6pmu_handle_irq,
1148         .enable                 = armv6pmu_enable_event,
1149         .disable                = armv6pmu_disable_event,
1150         .event_map              = armv6pmu_event_map,
1151         .raw_event              = armv6pmu_raw_event,
1152         .read_counter           = armv6pmu_read_counter,
1153         .write_counter          = armv6pmu_write_counter,
1154         .get_event_idx          = armv6pmu_get_event_idx,
1155         .start                  = armv6pmu_start,
1156         .stop                   = armv6pmu_stop,
1157         .num_events             = 3,
1158         .max_period             = (1LLU << 32) - 1,
1159 };
1160
1161 /*
1162  * ARMv6mpcore is almost identical to single core ARMv6 with the exception
1163  * that some of the events have different enumerations and that there is no
1164  * *hack* to stop the programmable counters. To stop the counters we simply
1165  * disable the interrupt reporting and update the event. When unthrottling we
1166  * reset the period and enable the interrupt reporting.
1167  */
1168 static const struct arm_pmu armv6mpcore_pmu = {
1169         .name                   = "v6mpcore",
1170         .handle_irq             = armv6pmu_handle_irq,
1171         .enable                 = armv6pmu_enable_event,
1172         .disable                = armv6mpcore_pmu_disable_event,
1173         .event_map              = armv6mpcore_pmu_event_map,
1174         .raw_event              = armv6pmu_raw_event,
1175         .read_counter           = armv6pmu_read_counter,
1176         .write_counter          = armv6pmu_write_counter,
1177         .get_event_idx          = armv6pmu_get_event_idx,
1178         .start                  = armv6pmu_start,
1179         .stop                   = armv6pmu_stop,
1180         .num_events             = 3,
1181         .max_period             = (1LLU << 32) - 1,
1182 };
1183
1184 /*
1185  * ARMv7 Cortex-A8 and Cortex-A9 Performance Events handling code.
1186  *
1187  * Copied from ARMv6 code, with the low level code inspired
1188  *  by the ARMv7 Oprofile code.
1189  *
1190  * Cortex-A8 has up to 4 configurable performance counters and
1191  *  a single cycle counter.
1192  * Cortex-A9 has up to 31 configurable performance counters and
1193  *  a single cycle counter.
1194  *
1195  * All counters can be enabled/disabled and IRQ masked separately. The cycle
1196  *  counter and all 4 performance counters together can be reset separately.
1197  */
1198
1199 #define ARMV7_PMU_CORTEX_A8_NAME                "ARMv7 Cortex-A8"
1200
1201 #define ARMV7_PMU_CORTEX_A9_NAME                "ARMv7 Cortex-A9"
1202
1203 /* Common ARMv7 event types */
1204 enum armv7_perf_types {
1205         ARMV7_PERFCTR_PMNC_SW_INCR              = 0x00,
1206         ARMV7_PERFCTR_IFETCH_MISS               = 0x01,
1207         ARMV7_PERFCTR_ITLB_MISS                 = 0x02,
1208         ARMV7_PERFCTR_DCACHE_REFILL             = 0x03,
1209         ARMV7_PERFCTR_DCACHE_ACCESS             = 0x04,
1210         ARMV7_PERFCTR_DTLB_REFILL               = 0x05,
1211         ARMV7_PERFCTR_DREAD                     = 0x06,
1212         ARMV7_PERFCTR_DWRITE                    = 0x07,
1213
1214         ARMV7_PERFCTR_EXC_TAKEN                 = 0x09,
1215         ARMV7_PERFCTR_EXC_EXECUTED              = 0x0A,
1216         ARMV7_PERFCTR_CID_WRITE                 = 0x0B,
1217         /* ARMV7_PERFCTR_PC_WRITE is equivalent to HW_BRANCH_INSTRUCTIONS.
1218          * It counts:
1219          *  - all branch instructions,
1220          *  - instructions that explicitly write the PC,
1221          *  - exception generating instructions.
1222          */
1223         ARMV7_PERFCTR_PC_WRITE                  = 0x0C,
1224         ARMV7_PERFCTR_PC_IMM_BRANCH             = 0x0D,
1225         ARMV7_PERFCTR_UNALIGNED_ACCESS          = 0x0F,
1226         ARMV7_PERFCTR_PC_BRANCH_MIS_PRED        = 0x10,
1227         ARMV7_PERFCTR_CLOCK_CYCLES              = 0x11,
1228
1229         ARMV7_PERFCTR_PC_BRANCH_MIS_USED        = 0x12,
1230
1231         ARMV7_PERFCTR_CPU_CYCLES                = 0xFF
1232 };
1233
1234 /* ARMv7 Cortex-A8 specific event types */
1235 enum armv7_a8_perf_types {
1236         ARMV7_PERFCTR_INSTR_EXECUTED            = 0x08,
1237
1238         ARMV7_PERFCTR_PC_PROC_RETURN            = 0x0E,
1239
1240         ARMV7_PERFCTR_WRITE_BUFFER_FULL         = 0x40,
1241         ARMV7_PERFCTR_L2_STORE_MERGED           = 0x41,
1242         ARMV7_PERFCTR_L2_STORE_BUFF             = 0x42,
1243         ARMV7_PERFCTR_L2_ACCESS                 = 0x43,
1244         ARMV7_PERFCTR_L2_CACH_MISS              = 0x44,
1245         ARMV7_PERFCTR_AXI_READ_CYCLES           = 0x45,
1246         ARMV7_PERFCTR_AXI_WRITE_CYCLES          = 0x46,
1247         ARMV7_PERFCTR_MEMORY_REPLAY             = 0x47,
1248         ARMV7_PERFCTR_UNALIGNED_ACCESS_REPLAY   = 0x48,
1249         ARMV7_PERFCTR_L1_DATA_MISS              = 0x49,
1250         ARMV7_PERFCTR_L1_INST_MISS              = 0x4A,
1251         ARMV7_PERFCTR_L1_DATA_COLORING          = 0x4B,
1252         ARMV7_PERFCTR_L1_NEON_DATA              = 0x4C,
1253         ARMV7_PERFCTR_L1_NEON_CACH_DATA         = 0x4D,
1254         ARMV7_PERFCTR_L2_NEON                   = 0x4E,
1255         ARMV7_PERFCTR_L2_NEON_HIT               = 0x4F,
1256         ARMV7_PERFCTR_L1_INST                   = 0x50,
1257         ARMV7_PERFCTR_PC_RETURN_MIS_PRED        = 0x51,
1258         ARMV7_PERFCTR_PC_BRANCH_FAILED          = 0x52,
1259         ARMV7_PERFCTR_PC_BRANCH_TAKEN           = 0x53,
1260         ARMV7_PERFCTR_PC_BRANCH_EXECUTED        = 0x54,
1261         ARMV7_PERFCTR_OP_EXECUTED               = 0x55,
1262         ARMV7_PERFCTR_CYCLES_INST_STALL         = 0x56,
1263         ARMV7_PERFCTR_CYCLES_INST               = 0x57,
1264         ARMV7_PERFCTR_CYCLES_NEON_DATA_STALL    = 0x58,
1265         ARMV7_PERFCTR_CYCLES_NEON_INST_STALL    = 0x59,
1266         ARMV7_PERFCTR_NEON_CYCLES               = 0x5A,
1267
1268         ARMV7_PERFCTR_PMU0_EVENTS               = 0x70,
1269         ARMV7_PERFCTR_PMU1_EVENTS               = 0x71,
1270         ARMV7_PERFCTR_PMU_EVENTS                = 0x72,
1271 };
1272
1273 /* ARMv7 Cortex-A9 specific event types */
1274 enum armv7_a9_perf_types {
1275         ARMV7_PERFCTR_JAVA_HW_BYTECODE_EXEC     = 0x40,
1276         ARMV7_PERFCTR_JAVA_SW_BYTECODE_EXEC     = 0x41,
1277         ARMV7_PERFCTR_JAZELLE_BRANCH_EXEC       = 0x42,
1278
1279         ARMV7_PERFCTR_COHERENT_LINE_MISS        = 0x50,
1280         ARMV7_PERFCTR_COHERENT_LINE_HIT         = 0x51,
1281
1282         ARMV7_PERFCTR_ICACHE_DEP_STALL_CYCLES   = 0x60,
1283         ARMV7_PERFCTR_DCACHE_DEP_STALL_CYCLES   = 0x61,
1284         ARMV7_PERFCTR_TLB_MISS_DEP_STALL_CYCLES = 0x62,
1285         ARMV7_PERFCTR_STREX_EXECUTED_PASSED     = 0x63,
1286         ARMV7_PERFCTR_STREX_EXECUTED_FAILED     = 0x64,
1287         ARMV7_PERFCTR_DATA_EVICTION             = 0x65,
1288         ARMV7_PERFCTR_ISSUE_STAGE_NO_INST       = 0x66,
1289         ARMV7_PERFCTR_ISSUE_STAGE_EMPTY         = 0x67,
1290         ARMV7_PERFCTR_INST_OUT_OF_RENAME_STAGE  = 0x68,
1291
1292         ARMV7_PERFCTR_PREDICTABLE_FUNCT_RETURNS = 0x6E,
1293
1294         ARMV7_PERFCTR_MAIN_UNIT_EXECUTED_INST   = 0x70,
1295         ARMV7_PERFCTR_SECOND_UNIT_EXECUTED_INST = 0x71,
1296         ARMV7_PERFCTR_LD_ST_UNIT_EXECUTED_INST  = 0x72,
1297         ARMV7_PERFCTR_FP_EXECUTED_INST          = 0x73,
1298         ARMV7_PERFCTR_NEON_EXECUTED_INST        = 0x74,
1299
1300         ARMV7_PERFCTR_PLD_FULL_DEP_STALL_CYCLES = 0x80,
1301         ARMV7_PERFCTR_DATA_WR_DEP_STALL_CYCLES  = 0x81,
1302         ARMV7_PERFCTR_ITLB_MISS_DEP_STALL_CYCLES        = 0x82,
1303         ARMV7_PERFCTR_DTLB_MISS_DEP_STALL_CYCLES        = 0x83,
1304         ARMV7_PERFCTR_MICRO_ITLB_MISS_DEP_STALL_CYCLES  = 0x84,
1305         ARMV7_PERFCTR_MICRO_DTLB_MISS_DEP_STALL_CYCLES  = 0x85,
1306         ARMV7_PERFCTR_DMB_DEP_STALL_CYCLES      = 0x86,
1307
1308         ARMV7_PERFCTR_INTGR_CLK_ENABLED_CYCLES  = 0x8A,
1309         ARMV7_PERFCTR_DATA_ENGINE_CLK_EN_CYCLES = 0x8B,
1310
1311         ARMV7_PERFCTR_ISB_INST                  = 0x90,
1312         ARMV7_PERFCTR_DSB_INST                  = 0x91,
1313         ARMV7_PERFCTR_DMB_INST                  = 0x92,
1314         ARMV7_PERFCTR_EXT_INTERRUPTS            = 0x93,
1315
1316         ARMV7_PERFCTR_PLE_CACHE_LINE_RQST_COMPLETED     = 0xA0,
1317         ARMV7_PERFCTR_PLE_CACHE_LINE_RQST_SKIPPED       = 0xA1,
1318         ARMV7_PERFCTR_PLE_FIFO_FLUSH            = 0xA2,
1319         ARMV7_PERFCTR_PLE_RQST_COMPLETED        = 0xA3,
1320         ARMV7_PERFCTR_PLE_FIFO_OVERFLOW         = 0xA4,
1321         ARMV7_PERFCTR_PLE_RQST_PROG             = 0xA5
1322 };
1323
1324 /*
1325  * Cortex-A8 HW events mapping
1326  *
1327  * The hardware events that we support. We do support cache operations but
1328  * we have harvard caches and no way to combine instruction and data
1329  * accesses/misses in hardware.
1330  */
1331 static const unsigned armv7_a8_perf_map[PERF_COUNT_HW_MAX] = {
1332         [PERF_COUNT_HW_CPU_CYCLES]          = ARMV7_PERFCTR_CPU_CYCLES,
1333         [PERF_COUNT_HW_INSTRUCTIONS]        = ARMV7_PERFCTR_INSTR_EXECUTED,
1334         [PERF_COUNT_HW_CACHE_REFERENCES]    = HW_OP_UNSUPPORTED,
1335         [PERF_COUNT_HW_CACHE_MISSES]        = HW_OP_UNSUPPORTED,
1336         [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = ARMV7_PERFCTR_PC_WRITE,
1337         [PERF_COUNT_HW_BRANCH_MISSES]       = ARMV7_PERFCTR_PC_BRANCH_MIS_PRED,
1338         [PERF_COUNT_HW_BUS_CYCLES]          = ARMV7_PERFCTR_CLOCK_CYCLES,
1339 };
1340
1341 static const unsigned armv7_a8_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
1342                                           [PERF_COUNT_HW_CACHE_OP_MAX]
1343                                           [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
1344         [C(L1D)] = {
1345                 /*
1346                  * The performance counters don't differentiate between read
1347                  * and write accesses/misses so this isn't strictly correct,
1348                  * but it's the best we can do. Writes and reads get
1349                  * combined.
1350                  */
1351                 [C(OP_READ)] = {
1352                         [C(RESULT_ACCESS)]      = ARMV7_PERFCTR_DCACHE_ACCESS,
1353                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_DCACHE_REFILL,
1354                 },
1355                 [C(OP_WRITE)] = {
1356                         [C(RESULT_ACCESS)]      = ARMV7_PERFCTR_DCACHE_ACCESS,
1357                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_DCACHE_REFILL,
1358                 },
1359                 [C(OP_PREFETCH)] = {
1360                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1361                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
1362                 },
1363         },
1364         [C(L1I)] = {
1365                 [C(OP_READ)] = {
1366                         [C(RESULT_ACCESS)]      = ARMV7_PERFCTR_L1_INST,
1367                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_L1_INST_MISS,
1368                 },
1369                 [C(OP_WRITE)] = {
1370                         [C(RESULT_ACCESS)]      = ARMV7_PERFCTR_L1_INST,
1371                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_L1_INST_MISS,
1372                 },
1373                 [C(OP_PREFETCH)] = {
1374                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1375                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
1376                 },
1377         },
1378         [C(LL)] = {
1379                 [C(OP_READ)] = {
1380                         [C(RESULT_ACCESS)]      = ARMV7_PERFCTR_L2_ACCESS,
1381                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_L2_CACH_MISS,
1382                 },
1383                 [C(OP_WRITE)] = {
1384                         [C(RESULT_ACCESS)]      = ARMV7_PERFCTR_L2_ACCESS,
1385                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_L2_CACH_MISS,
1386                 },
1387                 [C(OP_PREFETCH)] = {
1388                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1389                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
1390                 },
1391         },
1392         [C(DTLB)] = {
1393                 /*
1394                  * Only ITLB misses and DTLB refills are supported.
1395                  * If users want the DTLB refills misses a raw counter
1396                  * must be used.
1397                  */
1398                 [C(OP_READ)] = {
1399                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1400                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_DTLB_REFILL,
1401                 },
1402                 [C(OP_WRITE)] = {
1403                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1404                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_DTLB_REFILL,
1405                 },
1406                 [C(OP_PREFETCH)] = {
1407                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1408                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
1409                 },
1410         },
1411         [C(ITLB)] = {
1412                 [C(OP_READ)] = {
1413                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1414                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_ITLB_MISS,
1415                 },
1416                 [C(OP_WRITE)] = {
1417                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1418                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_ITLB_MISS,
1419                 },
1420                 [C(OP_PREFETCH)] = {
1421                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1422                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
1423                 },
1424         },
1425         [C(BPU)] = {
1426                 [C(OP_READ)] = {
1427                         [C(RESULT_ACCESS)]      = ARMV7_PERFCTR_PC_WRITE,
1428                         [C(RESULT_MISS)]
1429                                         = ARMV7_PERFCTR_PC_BRANCH_MIS_PRED,
1430                 },
1431                 [C(OP_WRITE)] = {
1432                         [C(RESULT_ACCESS)]      = ARMV7_PERFCTR_PC_WRITE,
1433                         [C(RESULT_MISS)]
1434                                         = ARMV7_PERFCTR_PC_BRANCH_MIS_PRED,
1435                 },
1436                 [C(OP_PREFETCH)] = {
1437                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1438                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
1439                 },
1440         },
1441 };
1442
1443 /*
1444  * Cortex-A9 HW events mapping
1445  */
1446 static const unsigned armv7_a9_perf_map[PERF_COUNT_HW_MAX] = {
1447         [PERF_COUNT_HW_CPU_CYCLES]          = ARMV7_PERFCTR_CPU_CYCLES,
1448         [PERF_COUNT_HW_INSTRUCTIONS]        =
1449                                         ARMV7_PERFCTR_INST_OUT_OF_RENAME_STAGE,
1450         [PERF_COUNT_HW_CACHE_REFERENCES]    = ARMV7_PERFCTR_COHERENT_LINE_HIT,
1451         [PERF_COUNT_HW_CACHE_MISSES]        = ARMV7_PERFCTR_COHERENT_LINE_MISS,
1452         [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = ARMV7_PERFCTR_PC_WRITE,
1453         [PERF_COUNT_HW_BRANCH_MISSES]       = ARMV7_PERFCTR_PC_BRANCH_MIS_PRED,
1454         [PERF_COUNT_HW_BUS_CYCLES]          = ARMV7_PERFCTR_CLOCK_CYCLES,
1455 };
1456
1457 static const unsigned armv7_a9_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
1458                                           [PERF_COUNT_HW_CACHE_OP_MAX]
1459                                           [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
1460         [C(L1D)] = {
1461                 /*
1462                  * The performance counters don't differentiate between read
1463                  * and write accesses/misses so this isn't strictly correct,
1464                  * but it's the best we can do. Writes and reads get
1465                  * combined.
1466                  */
1467                 [C(OP_READ)] = {
1468                         [C(RESULT_ACCESS)]      = ARMV7_PERFCTR_DCACHE_ACCESS,
1469                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_DCACHE_REFILL,
1470                 },
1471                 [C(OP_WRITE)] = {
1472                         [C(RESULT_ACCESS)]      = ARMV7_PERFCTR_DCACHE_ACCESS,
1473                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_DCACHE_REFILL,
1474                 },
1475                 [C(OP_PREFETCH)] = {
1476                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1477                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
1478                 },
1479         },
1480         [C(L1I)] = {
1481                 [C(OP_READ)] = {
1482                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1483                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_IFETCH_MISS,
1484                 },
1485                 [C(OP_WRITE)] = {
1486                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1487                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_IFETCH_MISS,
1488                 },
1489                 [C(OP_PREFETCH)] = {
1490                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1491                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
1492                 },
1493         },
1494         [C(LL)] = {
1495                 [C(OP_READ)] = {
1496                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1497                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
1498                 },
1499                 [C(OP_WRITE)] = {
1500                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1501                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
1502                 },
1503                 [C(OP_PREFETCH)] = {
1504                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1505                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
1506                 },
1507         },
1508         [C(DTLB)] = {
1509                 /*
1510                  * Only ITLB misses and DTLB refills are supported.
1511                  * If users want the DTLB refills misses a raw counter
1512                  * must be used.
1513                  */
1514                 [C(OP_READ)] = {
1515                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1516                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_DTLB_REFILL,
1517                 },
1518                 [C(OP_WRITE)] = {
1519                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1520                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_DTLB_REFILL,
1521                 },
1522                 [C(OP_PREFETCH)] = {
1523                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1524                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
1525                 },
1526         },
1527         [C(ITLB)] = {
1528                 [C(OP_READ)] = {
1529                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1530                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_ITLB_MISS,
1531                 },
1532                 [C(OP_WRITE)] = {
1533                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1534                         [C(RESULT_MISS)]        = ARMV7_PERFCTR_ITLB_MISS,
1535                 },
1536                 [C(OP_PREFETCH)] = {
1537                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1538                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
1539                 },
1540         },
1541         [C(BPU)] = {
1542                 [C(OP_READ)] = {
1543                         [C(RESULT_ACCESS)]      = ARMV7_PERFCTR_PC_WRITE,
1544                         [C(RESULT_MISS)]
1545                                         = ARMV7_PERFCTR_PC_BRANCH_MIS_PRED,
1546                 },
1547                 [C(OP_WRITE)] = {
1548                         [C(RESULT_ACCESS)]      = ARMV7_PERFCTR_PC_WRITE,
1549                         [C(RESULT_MISS)]
1550                                         = ARMV7_PERFCTR_PC_BRANCH_MIS_PRED,
1551                 },
1552                 [C(OP_PREFETCH)] = {
1553                         [C(RESULT_ACCESS)]      = CACHE_OP_UNSUPPORTED,
1554                         [C(RESULT_MISS)]        = CACHE_OP_UNSUPPORTED,
1555                 },
1556         },
1557 };
1558
1559 /*
1560  * Perf Events counters
1561  */
1562 enum armv7_counters {
1563         ARMV7_CYCLE_COUNTER             = 1,    /* Cycle counter */
1564         ARMV7_COUNTER0                  = 2,    /* First event counter */
1565 };
1566
1567 /*
1568  * The cycle counter is ARMV7_CYCLE_COUNTER.
1569  * The first event counter is ARMV7_COUNTER0.
1570  * The last event counter is (ARMV7_COUNTER0 + armpmu->num_events - 1).
1571  */
1572 #define ARMV7_COUNTER_LAST      (ARMV7_COUNTER0 + armpmu->num_events - 1)
1573
1574 /*
1575  * ARMv7 low level PMNC access
1576  */
1577
1578 /*
1579  * Per-CPU PMNC: config reg
1580  */
1581 #define ARMV7_PMNC_E            (1 << 0) /* Enable all counters */
1582 #define ARMV7_PMNC_P            (1 << 1) /* Reset all counters */
1583 #define ARMV7_PMNC_C            (1 << 2) /* Cycle counter reset */
1584 #define ARMV7_PMNC_D            (1 << 3) /* CCNT counts every 64th cpu cycle */
1585 #define ARMV7_PMNC_X            (1 << 4) /* Export to ETM */
1586 #define ARMV7_PMNC_DP           (1 << 5) /* Disable CCNT if non-invasive debug*/
1587 #define ARMV7_PMNC_N_SHIFT      11       /* Number of counters supported */
1588 #define ARMV7_PMNC_N_MASK       0x1f
1589 #define ARMV7_PMNC_MASK         0x3f     /* Mask for writable bits */
1590
1591 /*
1592  * Available counters
1593  */
1594 #define ARMV7_CNT0              0       /* First event counter */
1595 #define ARMV7_CCNT              31      /* Cycle counter */
1596
1597 /* Perf Event to low level counters mapping */
1598 #define ARMV7_EVENT_CNT_TO_CNTx (ARMV7_COUNTER0 - ARMV7_CNT0)
1599
1600 /*
1601  * CNTENS: counters enable reg
1602  */
1603 #define ARMV7_CNTENS_P(idx)     (1 << (idx - ARMV7_EVENT_CNT_TO_CNTx))
1604 #define ARMV7_CNTENS_C          (1 << ARMV7_CCNT)
1605
1606 /*
1607  * CNTENC: counters disable reg
1608  */
1609 #define ARMV7_CNTENC_P(idx)     (1 << (idx - ARMV7_EVENT_CNT_TO_CNTx))
1610 #define ARMV7_CNTENC_C          (1 << ARMV7_CCNT)
1611
1612 /*
1613  * INTENS: counters overflow interrupt enable reg
1614  */
1615 #define ARMV7_INTENS_P(idx)     (1 << (idx - ARMV7_EVENT_CNT_TO_CNTx))
1616 #define ARMV7_INTENS_C          (1 << ARMV7_CCNT)
1617
1618 /*
1619  * INTENC: counters overflow interrupt disable reg
1620  */
1621 #define ARMV7_INTENC_P(idx)     (1 << (idx - ARMV7_EVENT_CNT_TO_CNTx))
1622 #define ARMV7_INTENC_C          (1 << ARMV7_CCNT)
1623
1624 /*
1625  * EVTSEL: Event selection reg
1626  */
1627 #define ARMV7_EVTSEL_MASK       0x7f            /* Mask for writable bits */
1628
1629 /*
1630  * SELECT: Counter selection reg
1631  */
1632 #define ARMV7_SELECT_MASK       0x1f            /* Mask for writable bits */
1633
1634 /*
1635  * FLAG: counters overflow flag status reg
1636  */
1637 #define ARMV7_FLAG_P(idx)       (1 << (idx - ARMV7_EVENT_CNT_TO_CNTx))
1638 #define ARMV7_FLAG_C            (1 << ARMV7_CCNT)
1639 #define ARMV7_FLAG_MASK         0xffffffff      /* Mask for writable bits */
1640 #define ARMV7_OVERFLOWED_MASK   ARMV7_FLAG_MASK
1641
1642 static inline unsigned long armv7_pmnc_read(void)
1643 {
1644         u32 val;
1645         asm volatile("mrc p15, 0, %0, c9, c12, 0" : "=r"(val));
1646         return val;
1647 }
1648
1649 static inline void armv7_pmnc_write(unsigned long val)
1650 {
1651         val &= ARMV7_PMNC_MASK;
1652         asm volatile("mcr p15, 0, %0, c9, c12, 0" : : "r"(val));
1653 }
1654
1655 static inline int armv7_pmnc_has_overflowed(unsigned long pmnc)
1656 {
1657         return pmnc & ARMV7_OVERFLOWED_MASK;
1658 }
1659
1660 static inline int armv7_pmnc_counter_has_overflowed(unsigned long pmnc,
1661                                         enum armv7_counters counter)
1662 {
1663         int ret;
1664
1665         if (counter == ARMV7_CYCLE_COUNTER)
1666                 ret = pmnc & ARMV7_FLAG_C;
1667         else if ((counter >= ARMV7_COUNTER0) && (counter <= ARMV7_COUNTER_LAST))
1668                 ret = pmnc & ARMV7_FLAG_P(counter);
1669         else
1670                 pr_err("CPU%u checking wrong counter %d overflow status\n",
1671                         smp_processor_id(), counter);
1672
1673         return ret;
1674 }
1675
1676 static inline int armv7_pmnc_select_counter(unsigned int idx)
1677 {
1678         u32 val;
1679
1680         if ((idx < ARMV7_COUNTER0) || (idx > ARMV7_COUNTER_LAST)) {
1681                 pr_err("CPU%u selecting wrong PMNC counter"
1682                         " %d\n", smp_processor_id(), idx);
1683                 return -1;
1684         }
1685
1686         val = (idx - ARMV7_EVENT_CNT_TO_CNTx) & ARMV7_SELECT_MASK;
1687         asm volatile("mcr p15, 0, %0, c9, c12, 5" : : "r" (val));
1688
1689         return idx;
1690 }
1691
1692 static inline u32 armv7pmu_read_counter(int idx)
1693 {
1694         unsigned long value = 0;
1695
1696         if (idx == ARMV7_CYCLE_COUNTER)
1697                 asm volatile("mrc p15, 0, %0, c9, c13, 0" : "=r" (value));
1698         else if ((idx >= ARMV7_COUNTER0) && (idx <= ARMV7_COUNTER_LAST)) {
1699                 if (armv7_pmnc_select_counter(idx) == idx)
1700                         asm volatile("mrc p15, 0, %0, c9, c13, 2"
1701                                      : "=r" (value));
1702         } else
1703                 pr_err("CPU%u reading wrong counter %d\n",
1704                         smp_processor_id(), idx);
1705
1706         return value;
1707 }
1708
1709 static inline void armv7pmu_write_counter(int idx, u32 value)
1710 {
1711         if (idx == ARMV7_CYCLE_COUNTER)
1712                 asm volatile("mcr p15, 0, %0, c9, c13, 0" : : "r" (value));
1713         else if ((idx >= ARMV7_COUNTER0) && (idx <= ARMV7_COUNTER_LAST)) {
1714                 if (armv7_pmnc_select_counter(idx) == idx)
1715                         asm volatile("mcr p15, 0, %0, c9, c13, 2"
1716                                      : : "r" (value));
1717         } else
1718                 pr_err("CPU%u writing wrong counter %d\n",
1719                         smp_processor_id(), idx);
1720 }
1721
1722 static inline void armv7_pmnc_write_evtsel(unsigned int idx, u32 val)
1723 {
1724         if (armv7_pmnc_select_counter(idx) == idx) {
1725                 val &= ARMV7_EVTSEL_MASK;
1726                 asm volatile("mcr p15, 0, %0, c9, c13, 1" : : "r" (val));
1727         }
1728 }
1729
1730 static inline u32 armv7_pmnc_enable_counter(unsigned int idx)
1731 {
1732         u32 val;
1733
1734         if ((idx != ARMV7_CYCLE_COUNTER) &&
1735             ((idx < ARMV7_COUNTER0) || (idx > ARMV7_COUNTER_LAST))) {
1736                 pr_err("CPU%u enabling wrong PMNC counter"
1737                         " %d\n", smp_processor_id(), idx);
1738                 return -1;
1739         }
1740
1741         if (idx == ARMV7_CYCLE_COUNTER)
1742                 val = ARMV7_CNTENS_C;
1743         else
1744                 val = ARMV7_CNTENS_P(idx);
1745
1746         asm volatile("mcr p15, 0, %0, c9, c12, 1" : : "r" (val));
1747
1748         return idx;
1749 }
1750
1751 static inline u32 armv7_pmnc_disable_counter(unsigned int idx)
1752 {
1753         u32 val;
1754
1755
1756         if ((idx != ARMV7_CYCLE_COUNTER) &&
1757             ((idx < ARMV7_COUNTER0) || (idx > ARMV7_COUNTER_LAST))) {
1758                 pr_err("CPU%u disabling wrong PMNC counter"
1759                         " %d\n", smp_processor_id(), idx);
1760                 return -1;
1761         }
1762
1763         if (idx == ARMV7_CYCLE_COUNTER)
1764                 val = ARMV7_CNTENC_C;
1765         else
1766                 val = ARMV7_CNTENC_P(idx);
1767
1768         asm volatile("mcr p15, 0, %0, c9, c12, 2" : : "r" (val));
1769
1770         return idx;
1771 }
1772
1773 static inline u32 armv7_pmnc_enable_intens(unsigned int idx)
1774 {
1775         u32 val;
1776
1777         if ((idx != ARMV7_CYCLE_COUNTER) &&
1778             ((idx < ARMV7_COUNTER0) || (idx > ARMV7_COUNTER_LAST))) {
1779                 pr_err("CPU%u enabling wrong PMNC counter"
1780                         " interrupt enable %d\n", smp_processor_id(), idx);
1781                 return -1;
1782         }
1783
1784         if (idx == ARMV7_CYCLE_COUNTER)
1785                 val = ARMV7_INTENS_C;
1786         else
1787                 val = ARMV7_INTENS_P(idx);
1788
1789         asm volatile("mcr p15, 0, %0, c9, c14, 1" : : "r" (val));
1790
1791         return idx;
1792 }
1793
1794 static inline u32 armv7_pmnc_disable_intens(unsigned int idx)
1795 {
1796         u32 val;
1797
1798         if ((idx != ARMV7_CYCLE_COUNTER) &&
1799             ((idx < ARMV7_COUNTER0) || (idx > ARMV7_COUNTER_LAST))) {
1800                 pr_err("CPU%u disabling wrong PMNC counter"
1801                         " interrupt enable %d\n", smp_processor_id(), idx);
1802                 return -1;
1803         }
1804
1805         if (idx == ARMV7_CYCLE_COUNTER)
1806                 val = ARMV7_INTENC_C;
1807         else
1808                 val = ARMV7_INTENC_P(idx);
1809
1810         asm volatile("mcr p15, 0, %0, c9, c14, 2" : : "r" (val));
1811
1812         return idx;
1813 }
1814
1815 static inline u32 armv7_pmnc_getreset_flags(void)
1816 {
1817         u32 val;
1818
1819         /* Read */
1820         asm volatile("mrc p15, 0, %0, c9, c12, 3" : "=r" (val));
1821
1822         /* Write to clear flags */
1823         val &= ARMV7_FLAG_MASK;
1824         asm volatile("mcr p15, 0, %0, c9, c12, 3" : : "r" (val));
1825
1826         return val;
1827 }
1828
1829 #ifdef DEBUG
1830 static void armv7_pmnc_dump_regs(void)
1831 {
1832         u32 val;
1833         unsigned int cnt;
1834
1835         printk(KERN_INFO "PMNC registers dump:\n");
1836
1837         asm volatile("mrc p15, 0, %0, c9, c12, 0" : "=r" (val));
1838         printk(KERN_INFO "PMNC  =0x%08x\n", val);
1839
1840         asm volatile("mrc p15, 0, %0, c9, c12, 1" : "=r" (val));
1841         printk(KERN_INFO "CNTENS=0x%08x\n", val);
1842
1843         asm volatile("mrc p15, 0, %0, c9, c14, 1" : "=r" (val));
1844         printk(KERN_INFO "INTENS=0x%08x\n", val);
1845
1846         asm volatile("mrc p15, 0, %0, c9, c12, 3" : "=r" (val));
1847         printk(KERN_INFO "FLAGS =0x%08x\n", val);
1848
1849         asm volatile("mrc p15, 0, %0, c9, c12, 5" : "=r" (val));
1850         printk(KERN_INFO "SELECT=0x%08x\n", val);
1851
1852         asm volatile("mrc p15, 0, %0, c9, c13, 0" : "=r" (val));
1853         printk(KERN_INFO "CCNT  =0x%08x\n", val);
1854
1855         for (cnt = ARMV7_COUNTER0; cnt < ARMV7_COUNTER_LAST; cnt++) {
1856                 armv7_pmnc_select_counter(cnt);
1857                 asm volatile("mrc p15, 0, %0, c9, c13, 2" : "=r" (val));
1858                 printk(KERN_INFO "CNT[%d] count =0x%08x\n",
1859                         cnt-ARMV7_EVENT_CNT_TO_CNTx, val);
1860                 asm volatile("mrc p15, 0, %0, c9, c13, 1" : "=r" (val));
1861                 printk(KERN_INFO "CNT[%d] evtsel=0x%08x\n",
1862                         cnt-ARMV7_EVENT_CNT_TO_CNTx, val);
1863         }
1864 }
1865 #endif
1866
1867 void armv7pmu_enable_event(struct hw_perf_event *hwc, int idx)
1868 {
1869         unsigned long flags;
1870
1871         /*
1872          * Enable counter and interrupt, and set the counter to count
1873          * the event that we're interested in.
1874          */
1875         spin_lock_irqsave(&pmu_lock, flags);
1876
1877         /*
1878          * Disable counter
1879          */
1880         armv7_pmnc_disable_counter(idx);
1881
1882         /*
1883          * Set event (if destined for PMNx counters)
1884          * We don't need to set the event if it's a cycle count
1885          */
1886         if (idx != ARMV7_CYCLE_COUNTER)
1887                 armv7_pmnc_write_evtsel(idx, hwc->config_base);
1888
1889         /*
1890          * Enable interrupt for this counter
1891          */
1892         armv7_pmnc_enable_intens(idx);
1893
1894         /*
1895          * Enable counter
1896          */
1897         armv7_pmnc_enable_counter(idx);
1898
1899         spin_unlock_irqrestore(&pmu_lock, flags);
1900 }
1901
1902 static void armv7pmu_disable_event(struct hw_perf_event *hwc, int idx)
1903 {
1904         unsigned long flags;
1905
1906         /*
1907          * Disable counter and interrupt
1908          */
1909         spin_lock_irqsave(&pmu_lock, flags);
1910
1911         /*
1912          * Disable counter
1913          */
1914         armv7_pmnc_disable_counter(idx);
1915
1916         /*
1917          * Disable interrupt for this counter
1918          */
1919         armv7_pmnc_disable_intens(idx);
1920
1921         spin_unlock_irqrestore(&pmu_lock, flags);
1922 }
1923
1924 static irqreturn_t armv7pmu_handle_irq(int irq_num, void *dev)
1925 {
1926         unsigned long pmnc;
1927         struct perf_sample_data data;
1928         struct cpu_hw_events *cpuc;
1929         struct pt_regs *regs;
1930         int idx;
1931
1932         /*
1933          * Get and reset the IRQ flags
1934          */
1935         pmnc = armv7_pmnc_getreset_flags();
1936
1937         /*
1938          * Did an overflow occur?
1939          */
1940         if (!armv7_pmnc_has_overflowed(pmnc))
1941                 return IRQ_NONE;
1942
1943         /*
1944          * Handle the counter(s) overflow(s)
1945          */
1946         regs = get_irq_regs();
1947
1948         data.addr = 0;
1949
1950         cpuc = &__get_cpu_var(cpu_hw_events);
1951         for (idx = 0; idx <= armpmu->num_events; ++idx) {
1952                 struct perf_event *event = cpuc->events[idx];
1953                 struct hw_perf_event *hwc;
1954
1955                 if (!test_bit(idx, cpuc->active_mask))
1956                         continue;
1957
1958                 /*
1959                  * We have a single interrupt for all counters. Check that
1960                  * each counter has overflowed before we process it.
1961                  */
1962                 if (!armv7_pmnc_counter_has_overflowed(pmnc, idx))
1963                         continue;
1964
1965                 hwc = &event->hw;
1966                 armpmu_event_update(event, hwc, idx);
1967                 data.period = event->hw.last_period;
1968                 if (!armpmu_event_set_period(event, hwc, idx))
1969                         continue;
1970
1971                 if (perf_event_overflow(event, 0, &data, regs))
1972                         armpmu->disable(hwc, idx);
1973         }
1974
1975         /*
1976          * Handle the pending perf events.
1977          *
1978          * Note: this call *must* be run with interrupts enabled. For
1979          * platforms that can have the PMU interrupts raised as a PMI, this
1980          * will not work.
1981          */
1982         perf_event_do_pending();
1983
1984         return IRQ_HANDLED;
1985 }
1986
1987 static void armv7pmu_start(void)
1988 {
1989         unsigned long flags;
1990
1991         spin_lock_irqsave(&pmu_lock, flags);
1992         /* Enable all counters */
1993         armv7_pmnc_write(armv7_pmnc_read() | ARMV7_PMNC_E);
1994         spin_unlock_irqrestore(&pmu_lock, flags);
1995 }
1996
1997 static void armv7pmu_stop(void)
1998 {
1999         unsigned long flags;
2000
2001         spin_lock_irqsave(&pmu_lock, flags);
2002         /* Disable all counters */
2003         armv7_pmnc_write(armv7_pmnc_read() & ~ARMV7_PMNC_E);
2004         spin_unlock_irqrestore(&pmu_lock, flags);
2005 }
2006
2007 static inline int armv7_a8_pmu_event_map(int config)
2008 {
2009         int mapping = armv7_a8_perf_map[config];
2010         if (HW_OP_UNSUPPORTED == mapping)
2011                 mapping = -EOPNOTSUPP;
2012         return mapping;
2013 }
2014
2015 static inline int armv7_a9_pmu_event_map(int config)
2016 {
2017         int mapping = armv7_a9_perf_map[config];
2018         if (HW_OP_UNSUPPORTED == mapping)
2019                 mapping = -EOPNOTSUPP;
2020         return mapping;
2021 }
2022
2023 static u64 armv7pmu_raw_event(u64 config)
2024 {
2025         return config & 0xff;
2026 }
2027
2028 static int armv7pmu_get_event_idx(struct cpu_hw_events *cpuc,
2029                                   struct hw_perf_event *event)
2030 {
2031         int idx;
2032
2033         /* Always place a cycle counter into the cycle counter. */
2034         if (event->config_base == ARMV7_PERFCTR_CPU_CYCLES) {
2035                 if (test_and_set_bit(ARMV7_CYCLE_COUNTER, cpuc->used_mask))
2036                         return -EAGAIN;
2037
2038                 return ARMV7_CYCLE_COUNTER;
2039         } else {
2040                 /*
2041                  * For anything other than a cycle counter, try and use
2042                  * the events counters
2043                  */
2044                 for (idx = ARMV7_COUNTER0; idx <= armpmu->num_events; ++idx) {
2045                         if (!test_and_set_bit(idx, cpuc->used_mask))
2046                                 return idx;
2047                 }
2048
2049                 /* The counters are all in use. */
2050                 return -EAGAIN;
2051         }
2052 }
2053
2054 static struct arm_pmu armv7pmu = {
2055         .handle_irq             = armv7pmu_handle_irq,
2056         .enable                 = armv7pmu_enable_event,
2057         .disable                = armv7pmu_disable_event,
2058         .raw_event              = armv7pmu_raw_event,
2059         .read_counter           = armv7pmu_read_counter,
2060         .write_counter          = armv7pmu_write_counter,
2061         .get_event_idx          = armv7pmu_get_event_idx,
2062         .start                  = armv7pmu_start,
2063         .stop                   = armv7pmu_stop,
2064         .max_period             = (1LLU << 32) - 1,
2065 };
2066
2067 static u32 __init armv7_reset_read_pmnc(void)
2068 {
2069         u32 nb_cnt;
2070
2071         /* Initialize & Reset PMNC: C and P bits */
2072         armv7_pmnc_write(ARMV7_PMNC_P | ARMV7_PMNC_C);
2073
2074         /* Read the nb of CNTx counters supported from PMNC */
2075         nb_cnt = (armv7_pmnc_read() >> ARMV7_PMNC_N_SHIFT) & ARMV7_PMNC_N_MASK;
2076
2077         /* Add the CPU cycles counter and return */
2078         return nb_cnt + 1;
2079 }
2080
2081 static int __init
2082 init_hw_perf_events(void)
2083 {
2084         unsigned long cpuid = read_cpuid_id();
2085         unsigned long implementor = (cpuid & 0xFF000000) >> 24;
2086         unsigned long part_number = (cpuid & 0xFFF0);
2087
2088         /* We only support ARM CPUs implemented by ARM at the moment. */
2089         if (0x41 == implementor) {
2090                 switch (part_number) {
2091                 case 0xB360:    /* ARM1136 */
2092                 case 0xB560:    /* ARM1156 */
2093                 case 0xB760:    /* ARM1176 */
2094                         armpmu = &armv6pmu;
2095                         memcpy(armpmu_perf_cache_map, armv6_perf_cache_map,
2096                                         sizeof(armv6_perf_cache_map));
2097                         perf_max_events = armv6pmu.num_events;
2098                         break;
2099                 case 0xB020:    /* ARM11mpcore */
2100                         armpmu = &armv6mpcore_pmu;
2101                         memcpy(armpmu_perf_cache_map,
2102                                armv6mpcore_perf_cache_map,
2103                                sizeof(armv6mpcore_perf_cache_map));
2104                         perf_max_events = armv6mpcore_pmu.num_events;
2105                         break;
2106                 case 0xC080:    /* Cortex-A8 */
2107                         armv7pmu.name = ARMV7_PMU_CORTEX_A8_NAME;
2108                         memcpy(armpmu_perf_cache_map, armv7_a8_perf_cache_map,
2109                                 sizeof(armv7_a8_perf_cache_map));
2110                         armv7pmu.event_map = armv7_a8_pmu_event_map;
2111                         armpmu = &armv7pmu;
2112
2113                         /* Reset PMNC and read the nb of CNTx counters
2114                             supported */
2115                         armv7pmu.num_events = armv7_reset_read_pmnc();
2116                         perf_max_events = armv7pmu.num_events;
2117                         break;
2118                 case 0xC090:    /* Cortex-A9 */
2119                         armv7pmu.name = ARMV7_PMU_CORTEX_A9_NAME;
2120                         memcpy(armpmu_perf_cache_map, armv7_a9_perf_cache_map,
2121                                 sizeof(armv7_a9_perf_cache_map));
2122                         armv7pmu.event_map = armv7_a9_pmu_event_map;
2123                         armpmu = &armv7pmu;
2124
2125                         /* Reset PMNC and read the nb of CNTx counters
2126                             supported */
2127                         armv7pmu.num_events = armv7_reset_read_pmnc();
2128                         perf_max_events = armv7pmu.num_events;
2129                         break;
2130                 default:
2131                         pr_info("no hardware support available\n");
2132                         perf_max_events = -1;
2133                 }
2134         }
2135
2136         if (armpmu)
2137                 pr_info("enabled with %s PMU driver, %d counters available\n",
2138                         armpmu->name, armpmu->num_events);
2139
2140         return 0;
2141 }
2142 arch_initcall(init_hw_perf_events);
2143
2144 /*
2145  * Callchain handling code.
2146  */
2147 static inline void
2148 callchain_store(struct perf_callchain_entry *entry,
2149                 u64 ip)
2150 {
2151         if (entry->nr < PERF_MAX_STACK_DEPTH)
2152                 entry->ip[entry->nr++] = ip;
2153 }
2154
2155 /*
2156  * The registers we're interested in are at the end of the variable
2157  * length saved register structure. The fp points at the end of this
2158  * structure so the address of this struct is:
2159  * (struct frame_tail *)(xxx->fp)-1
2160  *
2161  * This code has been adapted from the ARM OProfile support.
2162  */
2163 struct frame_tail {
2164         struct frame_tail   *fp;
2165         unsigned long       sp;
2166         unsigned long       lr;
2167 } __attribute__((packed));
2168
2169 /*
2170  * Get the return address for a single stackframe and return a pointer to the
2171  * next frame tail.
2172  */
2173 static struct frame_tail *
2174 user_backtrace(struct frame_tail *tail,
2175                struct perf_callchain_entry *entry)
2176 {
2177         struct frame_tail buftail;
2178
2179         /* Also check accessibility of one struct frame_tail beyond */
2180         if (!access_ok(VERIFY_READ, tail, sizeof(buftail)))
2181                 return NULL;
2182         if (__copy_from_user_inatomic(&buftail, tail, sizeof(buftail)))
2183                 return NULL;
2184
2185         callchain_store(entry, buftail.lr);
2186
2187         /*
2188          * Frame pointers should strictly progress back up the stack
2189          * (towards higher addresses).
2190          */
2191         if (tail >= buftail.fp)
2192                 return NULL;
2193
2194         return buftail.fp - 1;
2195 }
2196
2197 static void
2198 perf_callchain_user(struct pt_regs *regs,
2199                     struct perf_callchain_entry *entry)
2200 {
2201         struct frame_tail *tail;
2202
2203         callchain_store(entry, PERF_CONTEXT_USER);
2204
2205         if (!user_mode(regs))
2206                 regs = task_pt_regs(current);
2207
2208         tail = (struct frame_tail *)regs->ARM_fp - 1;
2209
2210         while (tail && !((unsigned long)tail & 0x3))
2211                 tail = user_backtrace(tail, entry);
2212 }
2213
2214 /*
2215  * Gets called by walk_stackframe() for every stackframe. This will be called
2216  * whist unwinding the stackframe and is like a subroutine return so we use
2217  * the PC.
2218  */
2219 static int
2220 callchain_trace(struct stackframe *fr,
2221                 void *data)
2222 {
2223         struct perf_callchain_entry *entry = data;
2224         callchain_store(entry, fr->pc);
2225         return 0;
2226 }
2227
2228 static void
2229 perf_callchain_kernel(struct pt_regs *regs,
2230                       struct perf_callchain_entry *entry)
2231 {
2232         struct stackframe fr;
2233
2234         callchain_store(entry, PERF_CONTEXT_KERNEL);
2235         fr.fp = regs->ARM_fp;
2236         fr.sp = regs->ARM_sp;
2237         fr.lr = regs->ARM_lr;
2238         fr.pc = regs->ARM_pc;
2239         walk_stackframe(&fr, callchain_trace, entry);
2240 }
2241
2242 static void
2243 perf_do_callchain(struct pt_regs *regs,
2244                   struct perf_callchain_entry *entry)
2245 {
2246         int is_user;
2247
2248         if (!regs)
2249                 return;
2250
2251         is_user = user_mode(regs);
2252
2253         if (!current || !current->pid)
2254                 return;
2255
2256         if (is_user && current->state != TASK_RUNNING)
2257                 return;
2258
2259         if (!is_user)
2260                 perf_callchain_kernel(regs, entry);
2261
2262         if (current->mm)
2263                 perf_callchain_user(regs, entry);
2264 }
2265
2266 static DEFINE_PER_CPU(struct perf_callchain_entry, pmc_irq_entry);
2267
2268 struct perf_callchain_entry *
2269 perf_callchain(struct pt_regs *regs)
2270 {
2271         struct perf_callchain_entry *entry = &__get_cpu_var(pmc_irq_entry);
2272
2273         entry->nr = 0;
2274         perf_do_callchain(regs, entry);
2275         return entry;
2276 }