1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Driver for the L3 cache PMUs in Qualcomm Technologies chips. 4 * 5 * The driver supports a distributed cache architecture where the overall 6 * cache for a socket is comprised of multiple slices each with its own PMU. 7 * Access to each individual PMU is provided even though all CPUs share all 8 * the slices. User space needs to aggregate to individual counts to provide 9 * a global picture. 10 * 11 * See Documentation/admin-guide/perf/qcom_l3_pmu.rst for more details. 12 * 13 * Copyright (c) 2015-2017, The Linux Foundation. All rights reserved. 14 */ 15 16 #include <linux/acpi.h> 17 #include <linux/bitops.h> 18 #include <linux/interrupt.h> 19 #include <linux/io.h> 20 #include <linux/list.h> 21 #include <linux/module.h> 22 #include <linux/perf_event.h> 23 #include <linux/platform_device.h> 24 25 /* 26 * General constants 27 */ 28 29 /* Number of counters on each PMU */ 30 #define L3_NUM_COUNTERS 8 31 /* Mask for the event type field within perf_event_attr.config and EVTYPE reg */ 32 #define L3_EVTYPE_MASK 0xFF 33 /* 34 * Bit position of the 'long counter' flag within perf_event_attr.config. 35 * Reserve some space between the event type and this flag to allow expansion 36 * in the event type field. 37 */ 38 #define L3_EVENT_LC_BIT 32 39 40 /* 41 * Register offsets 42 */ 43 44 /* Perfmon registers */ 45 #define L3_HML3_PM_CR 0x000 46 #define L3_HML3_PM_EVCNTR(__cntr) (0x420 + ((__cntr) & 0x7) * 8) 47 #define L3_HML3_PM_CNTCTL(__cntr) (0x120 + ((__cntr) & 0x7) * 8) 48 #define L3_HML3_PM_EVTYPE(__cntr) (0x220 + ((__cntr) & 0x7) * 8) 49 #define L3_HML3_PM_FILTRA 0x300 50 #define L3_HML3_PM_FILTRB 0x308 51 #define L3_HML3_PM_FILTRC 0x310 52 #define L3_HML3_PM_FILTRAM 0x304 53 #define L3_HML3_PM_FILTRBM 0x30C 54 #define L3_HML3_PM_FILTRCM 0x314 55 56 /* Basic counter registers */ 57 #define L3_M_BC_CR 0x500 58 #define L3_M_BC_SATROLL_CR 0x504 59 #define L3_M_BC_CNTENSET 0x508 60 #define L3_M_BC_CNTENCLR 0x50C 61 #define L3_M_BC_INTENSET 0x510 62 #define L3_M_BC_INTENCLR 0x514 63 #define L3_M_BC_GANG 0x718 64 #define L3_M_BC_OVSR 0x740 65 #define L3_M_BC_IRQCTL 0x96C 66 67 /* 68 * Bit field definitions 69 */ 70 71 /* L3_HML3_PM_CR */ 72 #define PM_CR_RESET (0) 73 74 /* L3_HML3_PM_XCNTCTL/L3_HML3_PM_CNTCTLx */ 75 #define PMCNT_RESET (0) 76 77 /* L3_HML3_PM_EVTYPEx */ 78 #define EVSEL(__val) ((__val) & L3_EVTYPE_MASK) 79 80 /* Reset value for all the filter registers */ 81 #define PM_FLTR_RESET (0) 82 83 /* L3_M_BC_CR */ 84 #define BC_RESET (1UL << 1) 85 #define BC_ENABLE (1UL << 0) 86 87 /* L3_M_BC_SATROLL_CR */ 88 #define BC_SATROLL_CR_RESET (0) 89 90 /* L3_M_BC_CNTENSET */ 91 #define PMCNTENSET(__cntr) (1UL << ((__cntr) & 0x7)) 92 93 /* L3_M_BC_CNTENCLR */ 94 #define PMCNTENCLR(__cntr) (1UL << ((__cntr) & 0x7)) 95 #define BC_CNTENCLR_RESET (0xFF) 96 97 /* L3_M_BC_INTENSET */ 98 #define PMINTENSET(__cntr) (1UL << ((__cntr) & 0x7)) 99 100 /* L3_M_BC_INTENCLR */ 101 #define PMINTENCLR(__cntr) (1UL << ((__cntr) & 0x7)) 102 #define BC_INTENCLR_RESET (0xFF) 103 104 /* L3_M_BC_GANG */ 105 #define GANG_EN(__cntr) (1UL << ((__cntr) & 0x7)) 106 #define BC_GANG_RESET (0) 107 108 /* L3_M_BC_OVSR */ 109 #define PMOVSRCLR(__cntr) (1UL << ((__cntr) & 0x7)) 110 #define PMOVSRCLR_RESET (0xFF) 111 112 /* L3_M_BC_IRQCTL */ 113 #define PMIRQONMSBEN(__cntr) (1UL << ((__cntr) & 0x7)) 114 #define BC_IRQCTL_RESET (0x0) 115 116 /* 117 * Events 118 */ 119 120 #define L3_EVENT_CYCLES 0x01 121 #define L3_EVENT_READ_HIT 0x20 122 #define L3_EVENT_READ_MISS 0x21 123 #define L3_EVENT_READ_HIT_D 0x22 124 #define L3_EVENT_READ_MISS_D 0x23 125 #define L3_EVENT_WRITE_HIT 0x24 126 #define L3_EVENT_WRITE_MISS 0x25 127 128 /* 129 * Decoding of settings from perf_event_attr 130 * 131 * The config format for perf events is: 132 * - config: bits 0-7: event type 133 * bit 32: HW counter size requested, 0: 32 bits, 1: 64 bits 134 */ 135 136 static inline u32 get_event_type(struct perf_event *event) 137 { 138 return (event->attr.config) & L3_EVTYPE_MASK; 139 } 140 141 static inline bool event_uses_long_counter(struct perf_event *event) 142 { 143 return !!(event->attr.config & BIT_ULL(L3_EVENT_LC_BIT)); 144 } 145 146 static inline int event_num_counters(struct perf_event *event) 147 { 148 return event_uses_long_counter(event) ? 2 : 1; 149 } 150 151 /* 152 * Main PMU, inherits from the core perf PMU type 153 */ 154 struct l3cache_pmu { 155 struct pmu pmu; 156 struct hlist_node node; 157 void __iomem *regs; 158 struct perf_event *events[L3_NUM_COUNTERS]; 159 unsigned long used_mask[BITS_TO_LONGS(L3_NUM_COUNTERS)]; 160 cpumask_t cpumask; 161 }; 162 163 #define to_l3cache_pmu(p) (container_of(p, struct l3cache_pmu, pmu)) 164 165 /* 166 * Type used to group hardware counter operations 167 * 168 * Used to implement two types of hardware counters, standard (32bits) and 169 * long (64bits). The hardware supports counter chaining which we use to 170 * implement long counters. This support is exposed via the 'lc' flag field 171 * in perf_event_attr.config. 172 */ 173 struct l3cache_event_ops { 174 /* Called to start event monitoring */ 175 void (*start)(struct perf_event *event); 176 /* Called to stop event monitoring */ 177 void (*stop)(struct perf_event *event, int flags); 178 /* Called to update the perf_event */ 179 void (*update)(struct perf_event *event); 180 }; 181 182 /* 183 * Implementation of long counter operations 184 * 185 * 64bit counters are implemented by chaining two of the 32bit physical 186 * counters. The PMU only supports chaining of adjacent even/odd pairs 187 * and for simplicity the driver always configures the odd counter to 188 * count the overflows of the lower-numbered even counter. Note that since 189 * the resulting hardware counter is 64bits no IRQs are required to maintain 190 * the software counter which is also 64bits. 191 */ 192 193 static void qcom_l3_cache__64bit_counter_start(struct perf_event *event) 194 { 195 struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu); 196 int idx = event->hw.idx; 197 u32 evsel = get_event_type(event); 198 u32 gang; 199 200 /* Set the odd counter to count the overflows of the even counter */ 201 gang = readl_relaxed(l3pmu->regs + L3_M_BC_GANG); 202 gang |= GANG_EN(idx + 1); 203 writel_relaxed(gang, l3pmu->regs + L3_M_BC_GANG); 204 205 /* Initialize the hardware counters and reset prev_count*/ 206 local64_set(&event->hw.prev_count, 0); 207 writel_relaxed(0, l3pmu->regs + L3_HML3_PM_EVCNTR(idx + 1)); 208 writel_relaxed(0, l3pmu->regs + L3_HML3_PM_EVCNTR(idx)); 209 210 /* 211 * Set the event types, the upper half must use zero and the lower 212 * half the actual event type 213 */ 214 writel_relaxed(EVSEL(0), l3pmu->regs + L3_HML3_PM_EVTYPE(idx + 1)); 215 writel_relaxed(EVSEL(evsel), l3pmu->regs + L3_HML3_PM_EVTYPE(idx)); 216 217 /* Finally, enable the counters */ 218 writel_relaxed(PMCNT_RESET, l3pmu->regs + L3_HML3_PM_CNTCTL(idx + 1)); 219 writel_relaxed(PMCNTENSET(idx + 1), l3pmu->regs + L3_M_BC_CNTENSET); 220 writel_relaxed(PMCNT_RESET, l3pmu->regs + L3_HML3_PM_CNTCTL(idx)); 221 writel_relaxed(PMCNTENSET(idx), l3pmu->regs + L3_M_BC_CNTENSET); 222 } 223 224 static void qcom_l3_cache__64bit_counter_stop(struct perf_event *event, 225 int flags) 226 { 227 struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu); 228 int idx = event->hw.idx; 229 u32 gang = readl_relaxed(l3pmu->regs + L3_M_BC_GANG); 230 231 /* Disable the counters */ 232 writel_relaxed(PMCNTENCLR(idx), l3pmu->regs + L3_M_BC_CNTENCLR); 233 writel_relaxed(PMCNTENCLR(idx + 1), l3pmu->regs + L3_M_BC_CNTENCLR); 234 235 /* Disable chaining */ 236 writel_relaxed(gang & ~GANG_EN(idx + 1), l3pmu->regs + L3_M_BC_GANG); 237 } 238 239 static void qcom_l3_cache__64bit_counter_update(struct perf_event *event) 240 { 241 struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu); 242 int idx = event->hw.idx; 243 u32 hi, lo; 244 u64 prev, new; 245 246 do { 247 prev = local64_read(&event->hw.prev_count); 248 do { 249 hi = readl_relaxed(l3pmu->regs + L3_HML3_PM_EVCNTR(idx + 1)); 250 lo = readl_relaxed(l3pmu->regs + L3_HML3_PM_EVCNTR(idx)); 251 } while (hi != readl_relaxed(l3pmu->regs + L3_HML3_PM_EVCNTR(idx + 1))); 252 new = ((u64)hi << 32) | lo; 253 } while (local64_cmpxchg(&event->hw.prev_count, prev, new) != prev); 254 255 local64_add(new - prev, &event->count); 256 } 257 258 static const struct l3cache_event_ops event_ops_long = { 259 .start = qcom_l3_cache__64bit_counter_start, 260 .stop = qcom_l3_cache__64bit_counter_stop, 261 .update = qcom_l3_cache__64bit_counter_update, 262 }; 263 264 /* 265 * Implementation of standard counter operations 266 * 267 * 32bit counters use a single physical counter and a hardware feature that 268 * asserts the overflow IRQ on the toggling of the most significant bit in 269 * the counter. This feature allows the counters to be left free-running 270 * without needing the usual reprogramming required to properly handle races 271 * during concurrent calls to update. 272 */ 273 274 static void qcom_l3_cache__32bit_counter_start(struct perf_event *event) 275 { 276 struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu); 277 int idx = event->hw.idx; 278 u32 evsel = get_event_type(event); 279 u32 irqctl = readl_relaxed(l3pmu->regs + L3_M_BC_IRQCTL); 280 281 /* Set the counter to assert the overflow IRQ on MSB toggling */ 282 writel_relaxed(irqctl | PMIRQONMSBEN(idx), l3pmu->regs + L3_M_BC_IRQCTL); 283 284 /* Initialize the hardware counter and reset prev_count*/ 285 local64_set(&event->hw.prev_count, 0); 286 writel_relaxed(0, l3pmu->regs + L3_HML3_PM_EVCNTR(idx)); 287 288 /* Set the event type */ 289 writel_relaxed(EVSEL(evsel), l3pmu->regs + L3_HML3_PM_EVTYPE(idx)); 290 291 /* Enable interrupt generation by this counter */ 292 writel_relaxed(PMINTENSET(idx), l3pmu->regs + L3_M_BC_INTENSET); 293 294 /* Finally, enable the counter */ 295 writel_relaxed(PMCNT_RESET, l3pmu->regs + L3_HML3_PM_CNTCTL(idx)); 296 writel_relaxed(PMCNTENSET(idx), l3pmu->regs + L3_M_BC_CNTENSET); 297 } 298 299 static void qcom_l3_cache__32bit_counter_stop(struct perf_event *event, 300 int flags) 301 { 302 struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu); 303 int idx = event->hw.idx; 304 u32 irqctl = readl_relaxed(l3pmu->regs + L3_M_BC_IRQCTL); 305 306 /* Disable the counter */ 307 writel_relaxed(PMCNTENCLR(idx), l3pmu->regs + L3_M_BC_CNTENCLR); 308 309 /* Disable interrupt generation by this counter */ 310 writel_relaxed(PMINTENCLR(idx), l3pmu->regs + L3_M_BC_INTENCLR); 311 312 /* Set the counter to not assert the overflow IRQ on MSB toggling */ 313 writel_relaxed(irqctl & ~PMIRQONMSBEN(idx), l3pmu->regs + L3_M_BC_IRQCTL); 314 } 315 316 static void qcom_l3_cache__32bit_counter_update(struct perf_event *event) 317 { 318 struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu); 319 int idx = event->hw.idx; 320 u32 prev, new; 321 322 do { 323 prev = local64_read(&event->hw.prev_count); 324 new = readl_relaxed(l3pmu->regs + L3_HML3_PM_EVCNTR(idx)); 325 } while (local64_cmpxchg(&event->hw.prev_count, prev, new) != prev); 326 327 local64_add(new - prev, &event->count); 328 } 329 330 static const struct l3cache_event_ops event_ops_std = { 331 .start = qcom_l3_cache__32bit_counter_start, 332 .stop = qcom_l3_cache__32bit_counter_stop, 333 .update = qcom_l3_cache__32bit_counter_update, 334 }; 335 336 /* Retrieve the appropriate operations for the given event */ 337 static 338 const struct l3cache_event_ops *l3cache_event_get_ops(struct perf_event *event) 339 { 340 if (event_uses_long_counter(event)) 341 return &event_ops_long; 342 else 343 return &event_ops_std; 344 } 345 346 /* 347 * Top level PMU functions. 348 */ 349 350 static inline void qcom_l3_cache__init(struct l3cache_pmu *l3pmu) 351 { 352 int i; 353 354 writel_relaxed(BC_RESET, l3pmu->regs + L3_M_BC_CR); 355 356 /* 357 * Use writel for the first programming command to ensure the basic 358 * counter unit is stopped before proceeding 359 */ 360 writel(BC_SATROLL_CR_RESET, l3pmu->regs + L3_M_BC_SATROLL_CR); 361 362 writel_relaxed(BC_CNTENCLR_RESET, l3pmu->regs + L3_M_BC_CNTENCLR); 363 writel_relaxed(BC_INTENCLR_RESET, l3pmu->regs + L3_M_BC_INTENCLR); 364 writel_relaxed(PMOVSRCLR_RESET, l3pmu->regs + L3_M_BC_OVSR); 365 writel_relaxed(BC_GANG_RESET, l3pmu->regs + L3_M_BC_GANG); 366 writel_relaxed(BC_IRQCTL_RESET, l3pmu->regs + L3_M_BC_IRQCTL); 367 writel_relaxed(PM_CR_RESET, l3pmu->regs + L3_HML3_PM_CR); 368 369 for (i = 0; i < L3_NUM_COUNTERS; ++i) { 370 writel_relaxed(PMCNT_RESET, l3pmu->regs + L3_HML3_PM_CNTCTL(i)); 371 writel_relaxed(EVSEL(0), l3pmu->regs + L3_HML3_PM_EVTYPE(i)); 372 } 373 374 writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRA); 375 writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRAM); 376 writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRB); 377 writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRBM); 378 writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRC); 379 writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRCM); 380 381 /* 382 * Use writel here to ensure all programming commands are done 383 * before proceeding 384 */ 385 writel(BC_ENABLE, l3pmu->regs + L3_M_BC_CR); 386 } 387 388 static irqreturn_t qcom_l3_cache__handle_irq(int irq_num, void *data) 389 { 390 struct l3cache_pmu *l3pmu = data; 391 /* Read the overflow status register */ 392 long status = readl_relaxed(l3pmu->regs + L3_M_BC_OVSR); 393 int idx; 394 395 if (status == 0) 396 return IRQ_NONE; 397 398 /* Clear the bits we read on the overflow status register */ 399 writel_relaxed(status, l3pmu->regs + L3_M_BC_OVSR); 400 401 for_each_set_bit(idx, &status, L3_NUM_COUNTERS) { 402 struct perf_event *event; 403 const struct l3cache_event_ops *ops; 404 405 event = l3pmu->events[idx]; 406 if (!event) 407 continue; 408 409 /* 410 * Since the IRQ is not enabled for events using long counters 411 * we should never see one of those here, however, be consistent 412 * and use the ops indirections like in the other operations. 413 */ 414 415 ops = l3cache_event_get_ops(event); 416 ops->update(event); 417 } 418 419 return IRQ_HANDLED; 420 } 421 422 /* 423 * Implementation of abstract pmu functionality required by 424 * the core perf events code. 425 */ 426 427 static void qcom_l3_cache__pmu_enable(struct pmu *pmu) 428 { 429 struct l3cache_pmu *l3pmu = to_l3cache_pmu(pmu); 430 431 /* Ensure the other programming commands are observed before enabling */ 432 wmb(); 433 434 writel_relaxed(BC_ENABLE, l3pmu->regs + L3_M_BC_CR); 435 } 436 437 static void qcom_l3_cache__pmu_disable(struct pmu *pmu) 438 { 439 struct l3cache_pmu *l3pmu = to_l3cache_pmu(pmu); 440 441 writel_relaxed(0, l3pmu->regs + L3_M_BC_CR); 442 443 /* Ensure the basic counter unit is stopped before proceeding */ 444 wmb(); 445 } 446 447 /* 448 * We must NOT create groups containing events from multiple hardware PMUs, 449 * although mixing different software and hardware PMUs is allowed. 450 */ 451 static bool qcom_l3_cache__validate_event_group(struct perf_event *event) 452 { 453 struct perf_event *leader = event->group_leader; 454 struct perf_event *sibling; 455 int counters = 0; 456 457 if (leader->pmu != event->pmu && !is_software_event(leader)) 458 return false; 459 460 counters = event_num_counters(event); 461 counters += event_num_counters(leader); 462 463 for_each_sibling_event(sibling, leader) { 464 if (is_software_event(sibling)) 465 continue; 466 if (sibling->pmu != event->pmu) 467 return false; 468 counters += event_num_counters(sibling); 469 } 470 471 /* 472 * If the group requires more counters than the HW has, it 473 * cannot ever be scheduled. 474 */ 475 return counters <= L3_NUM_COUNTERS; 476 } 477 478 static int qcom_l3_cache__event_init(struct perf_event *event) 479 { 480 struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu); 481 struct hw_perf_event *hwc = &event->hw; 482 483 /* 484 * Is the event for this PMU? 485 */ 486 if (event->attr.type != event->pmu->type) 487 return -ENOENT; 488 489 /* 490 * Sampling not supported since these events are not core-attributable. 491 */ 492 if (hwc->sample_period) 493 return -EINVAL; 494 495 /* 496 * Task mode not available, we run the counters as socket counters, 497 * not attributable to any CPU and therefore cannot attribute per-task. 498 */ 499 if (event->cpu < 0) 500 return -EINVAL; 501 502 /* Validate the group */ 503 if (!qcom_l3_cache__validate_event_group(event)) 504 return -EINVAL; 505 506 hwc->idx = -1; 507 508 /* 509 * Many perf core operations (eg. events rotation) operate on a 510 * single CPU context. This is obvious for CPU PMUs, where one 511 * expects the same sets of events being observed on all CPUs, 512 * but can lead to issues for off-core PMUs, like this one, where 513 * each event could be theoretically assigned to a different CPU. 514 * To mitigate this, we enforce CPU assignment to one designated 515 * processor (the one described in the "cpumask" attribute exported 516 * by the PMU device). perf user space tools honor this and avoid 517 * opening more than one copy of the events. 518 */ 519 event->cpu = cpumask_first(&l3pmu->cpumask); 520 521 return 0; 522 } 523 524 static void qcom_l3_cache__event_start(struct perf_event *event, int flags) 525 { 526 struct hw_perf_event *hwc = &event->hw; 527 const struct l3cache_event_ops *ops = l3cache_event_get_ops(event); 528 529 hwc->state = 0; 530 ops->start(event); 531 } 532 533 static void qcom_l3_cache__event_stop(struct perf_event *event, int flags) 534 { 535 struct hw_perf_event *hwc = &event->hw; 536 const struct l3cache_event_ops *ops = l3cache_event_get_ops(event); 537 538 if (hwc->state & PERF_HES_STOPPED) 539 return; 540 541 ops->stop(event, flags); 542 if (flags & PERF_EF_UPDATE) 543 ops->update(event); 544 hwc->state |= PERF_HES_STOPPED | PERF_HES_UPTODATE; 545 } 546 547 static int qcom_l3_cache__event_add(struct perf_event *event, int flags) 548 { 549 struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu); 550 struct hw_perf_event *hwc = &event->hw; 551 int order = event_uses_long_counter(event) ? 1 : 0; 552 int idx; 553 554 /* 555 * Try to allocate a counter. 556 */ 557 idx = bitmap_find_free_region(l3pmu->used_mask, L3_NUM_COUNTERS, order); 558 if (idx < 0) 559 /* The counters are all in use. */ 560 return -EAGAIN; 561 562 hwc->idx = idx; 563 hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE; 564 l3pmu->events[idx] = event; 565 566 if (flags & PERF_EF_START) 567 qcom_l3_cache__event_start(event, 0); 568 569 /* Propagate changes to the userspace mapping. */ 570 perf_event_update_userpage(event); 571 572 return 0; 573 } 574 575 static void qcom_l3_cache__event_del(struct perf_event *event, int flags) 576 { 577 struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu); 578 struct hw_perf_event *hwc = &event->hw; 579 int order = event_uses_long_counter(event) ? 1 : 0; 580 581 /* Stop and clean up */ 582 qcom_l3_cache__event_stop(event, flags | PERF_EF_UPDATE); 583 l3pmu->events[hwc->idx] = NULL; 584 bitmap_release_region(l3pmu->used_mask, hwc->idx, order); 585 586 /* Propagate changes to the userspace mapping. */ 587 perf_event_update_userpage(event); 588 } 589 590 static void qcom_l3_cache__event_read(struct perf_event *event) 591 { 592 const struct l3cache_event_ops *ops = l3cache_event_get_ops(event); 593 594 ops->update(event); 595 } 596 597 /* 598 * Add sysfs attributes 599 * 600 * We export: 601 * - formats, used by perf user space and other tools to configure events 602 * - events, used by perf user space and other tools to create events 603 * symbolically, e.g.: 604 * perf stat -a -e l3cache_0_0/event=read-miss/ ls 605 * perf stat -a -e l3cache_0_0/event=0x21/ ls 606 * - cpumask, used by perf user space and other tools to know on which CPUs 607 * to open the events 608 */ 609 610 /* formats */ 611 612 #define L3CACHE_PMU_FORMAT_ATTR(_name, _config) \ 613 (&((struct dev_ext_attribute[]) { \ 614 { .attr = __ATTR(_name, 0444, device_show_string, NULL), \ 615 .var = (void *) _config, } \ 616 })[0].attr.attr) 617 618 static struct attribute *qcom_l3_cache_pmu_formats[] = { 619 L3CACHE_PMU_FORMAT_ATTR(event, "config:0-7"), 620 L3CACHE_PMU_FORMAT_ATTR(lc, "config:" __stringify(L3_EVENT_LC_BIT)), 621 NULL, 622 }; 623 624 static const struct attribute_group qcom_l3_cache_pmu_format_group = { 625 .name = "format", 626 .attrs = qcom_l3_cache_pmu_formats, 627 }; 628 629 /* events */ 630 631 static ssize_t l3cache_pmu_event_show(struct device *dev, 632 struct device_attribute *attr, char *page) 633 { 634 struct perf_pmu_events_attr *pmu_attr; 635 636 pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr); 637 return sysfs_emit(page, "event=0x%02llx\n", pmu_attr->id); 638 } 639 640 #define L3CACHE_EVENT_ATTR(_name, _id) \ 641 PMU_EVENT_ATTR_ID(_name, l3cache_pmu_event_show, _id) 642 643 static struct attribute *qcom_l3_cache_pmu_events[] = { 644 L3CACHE_EVENT_ATTR(cycles, L3_EVENT_CYCLES), 645 L3CACHE_EVENT_ATTR(read-hit, L3_EVENT_READ_HIT), 646 L3CACHE_EVENT_ATTR(read-miss, L3_EVENT_READ_MISS), 647 L3CACHE_EVENT_ATTR(read-hit-d-side, L3_EVENT_READ_HIT_D), 648 L3CACHE_EVENT_ATTR(read-miss-d-side, L3_EVENT_READ_MISS_D), 649 L3CACHE_EVENT_ATTR(write-hit, L3_EVENT_WRITE_HIT), 650 L3CACHE_EVENT_ATTR(write-miss, L3_EVENT_WRITE_MISS), 651 NULL 652 }; 653 654 static const struct attribute_group qcom_l3_cache_pmu_events_group = { 655 .name = "events", 656 .attrs = qcom_l3_cache_pmu_events, 657 }; 658 659 /* cpumask */ 660 661 static ssize_t cpumask_show(struct device *dev, 662 struct device_attribute *attr, char *buf) 663 { 664 struct l3cache_pmu *l3pmu = to_l3cache_pmu(dev_get_drvdata(dev)); 665 666 return cpumap_print_to_pagebuf(true, buf, &l3pmu->cpumask); 667 } 668 669 static DEVICE_ATTR_RO(cpumask); 670 671 static struct attribute *qcom_l3_cache_pmu_cpumask_attrs[] = { 672 &dev_attr_cpumask.attr, 673 NULL, 674 }; 675 676 static const struct attribute_group qcom_l3_cache_pmu_cpumask_attr_group = { 677 .attrs = qcom_l3_cache_pmu_cpumask_attrs, 678 }; 679 680 /* 681 * Per PMU device attribute groups 682 */ 683 static const struct attribute_group *qcom_l3_cache_pmu_attr_grps[] = { 684 &qcom_l3_cache_pmu_format_group, 685 &qcom_l3_cache_pmu_events_group, 686 &qcom_l3_cache_pmu_cpumask_attr_group, 687 NULL, 688 }; 689 690 /* 691 * Probing functions and data. 692 */ 693 694 static int qcom_l3_cache_pmu_online_cpu(unsigned int cpu, struct hlist_node *node) 695 { 696 struct l3cache_pmu *l3pmu = hlist_entry_safe(node, struct l3cache_pmu, node); 697 698 /* If there is not a CPU/PMU association pick this CPU */ 699 if (cpumask_empty(&l3pmu->cpumask)) 700 cpumask_set_cpu(cpu, &l3pmu->cpumask); 701 702 return 0; 703 } 704 705 static int qcom_l3_cache_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node) 706 { 707 struct l3cache_pmu *l3pmu = hlist_entry_safe(node, struct l3cache_pmu, node); 708 unsigned int target; 709 710 if (!cpumask_test_and_clear_cpu(cpu, &l3pmu->cpumask)) 711 return 0; 712 target = cpumask_any_but(cpu_online_mask, cpu); 713 if (target >= nr_cpu_ids) 714 return 0; 715 perf_pmu_migrate_context(&l3pmu->pmu, cpu, target); 716 cpumask_set_cpu(target, &l3pmu->cpumask); 717 return 0; 718 } 719 720 static int qcom_l3_cache_pmu_probe(struct platform_device *pdev) 721 { 722 struct l3cache_pmu *l3pmu; 723 struct acpi_device *acpi_dev; 724 struct resource *memrc; 725 int ret; 726 char *name; 727 728 /* Initialize the PMU data structures */ 729 730 acpi_dev = ACPI_COMPANION(&pdev->dev); 731 if (!acpi_dev) 732 return -ENODEV; 733 734 l3pmu = devm_kzalloc(&pdev->dev, sizeof(*l3pmu), GFP_KERNEL); 735 name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "l3cache_%s_%s", 736 acpi_device_uid(acpi_dev_parent(acpi_dev)), 737 acpi_device_uid(acpi_dev)); 738 if (!l3pmu || !name) 739 return -ENOMEM; 740 741 l3pmu->pmu = (struct pmu) { 742 .parent = &pdev->dev, 743 .task_ctx_nr = perf_invalid_context, 744 745 .pmu_enable = qcom_l3_cache__pmu_enable, 746 .pmu_disable = qcom_l3_cache__pmu_disable, 747 .event_init = qcom_l3_cache__event_init, 748 .add = qcom_l3_cache__event_add, 749 .del = qcom_l3_cache__event_del, 750 .start = qcom_l3_cache__event_start, 751 .stop = qcom_l3_cache__event_stop, 752 .read = qcom_l3_cache__event_read, 753 754 .attr_groups = qcom_l3_cache_pmu_attr_grps, 755 .capabilities = PERF_PMU_CAP_NO_EXCLUDE, 756 }; 757 758 l3pmu->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &memrc); 759 if (IS_ERR(l3pmu->regs)) 760 return PTR_ERR(l3pmu->regs); 761 762 qcom_l3_cache__init(l3pmu); 763 764 ret = platform_get_irq(pdev, 0); 765 if (ret <= 0) 766 return ret; 767 768 ret = devm_request_irq(&pdev->dev, ret, qcom_l3_cache__handle_irq, 0, 769 name, l3pmu); 770 if (ret) { 771 dev_err(&pdev->dev, "Request for IRQ failed for slice @%pa\n", 772 &memrc->start); 773 return ret; 774 } 775 776 /* Add this instance to the list used by the offline callback */ 777 ret = cpuhp_state_add_instance(CPUHP_AP_PERF_ARM_QCOM_L3_ONLINE, &l3pmu->node); 778 if (ret) { 779 dev_err(&pdev->dev, "Error %d registering hotplug", ret); 780 return ret; 781 } 782 783 ret = perf_pmu_register(&l3pmu->pmu, name, -1); 784 if (ret < 0) { 785 dev_err(&pdev->dev, "Failed to register L3 cache PMU (%d)\n", ret); 786 return ret; 787 } 788 789 dev_info(&pdev->dev, "Registered %s, type: %d\n", name, l3pmu->pmu.type); 790 791 return 0; 792 } 793 794 static const struct acpi_device_id qcom_l3_cache_pmu_acpi_match[] = { 795 { "QCOM8081", }, 796 { } 797 }; 798 MODULE_DEVICE_TABLE(acpi, qcom_l3_cache_pmu_acpi_match); 799 800 static struct platform_driver qcom_l3_cache_pmu_driver = { 801 .driver = { 802 .name = "qcom-l3cache-pmu", 803 .acpi_match_table = ACPI_PTR(qcom_l3_cache_pmu_acpi_match), 804 .suppress_bind_attrs = true, 805 }, 806 .probe = qcom_l3_cache_pmu_probe, 807 }; 808 809 static int __init register_qcom_l3_cache_pmu_driver(void) 810 { 811 int ret; 812 813 /* Install a hook to update the reader CPU in case it goes offline */ 814 ret = cpuhp_setup_state_multi(CPUHP_AP_PERF_ARM_QCOM_L3_ONLINE, 815 "perf/qcom/l3cache:online", 816 qcom_l3_cache_pmu_online_cpu, 817 qcom_l3_cache_pmu_offline_cpu); 818 if (ret) 819 return ret; 820 821 return platform_driver_register(&qcom_l3_cache_pmu_driver); 822 } 823 device_initcall(register_qcom_l3_cache_pmu_driver); 824