1 /* 2 * Driver for the L3 cache PMUs in Qualcomm Technologies chips. 3 * 4 * The driver supports a distributed cache architecture where the overall 5 * cache for a socket is comprised of multiple slices each with its own PMU. 6 * Access to each individual PMU is provided even though all CPUs share all 7 * the slices. User space needs to aggregate to individual counts to provide 8 * a global picture. 9 * 10 * See Documentation/perf/qcom_l3_pmu.txt for more details. 11 * 12 * Copyright (c) 2015-2017, The Linux Foundation. All rights reserved. 13 * 14 * This program is free software; you can redistribute it and/or modify 15 * it under the terms of the GNU General Public License version 2 and 16 * only version 2 as published by the Free Software Foundation. 17 * 18 * This program is distributed in the hope that it will be useful, 19 * but WITHOUT ANY WARRANTY; without even the implied warranty of 20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 21 * GNU General Public License for more details. 22 */ 23 24 #include <linux/acpi.h> 25 #include <linux/bitops.h> 26 #include <linux/interrupt.h> 27 #include <linux/io.h> 28 #include <linux/list.h> 29 #include <linux/module.h> 30 #include <linux/perf_event.h> 31 #include <linux/platform_device.h> 32 33 /* 34 * General constants 35 */ 36 37 /* Number of counters on each PMU */ 38 #define L3_NUM_COUNTERS 8 39 /* Mask for the event type field within perf_event_attr.config and EVTYPE reg */ 40 #define L3_EVTYPE_MASK 0xFF 41 /* 42 * Bit position of the 'long counter' flag within perf_event_attr.config. 43 * Reserve some space between the event type and this flag to allow expansion 44 * in the event type field. 45 */ 46 #define L3_EVENT_LC_BIT 32 47 48 /* 49 * Register offsets 50 */ 51 52 /* Perfmon registers */ 53 #define L3_HML3_PM_CR 0x000 54 #define L3_HML3_PM_EVCNTR(__cntr) (0x420 + ((__cntr) & 0x7) * 8) 55 #define L3_HML3_PM_CNTCTL(__cntr) (0x120 + ((__cntr) & 0x7) * 8) 56 #define L3_HML3_PM_EVTYPE(__cntr) (0x220 + ((__cntr) & 0x7) * 8) 57 #define L3_HML3_PM_FILTRA 0x300 58 #define L3_HML3_PM_FILTRB 0x308 59 #define L3_HML3_PM_FILTRC 0x310 60 #define L3_HML3_PM_FILTRAM 0x304 61 #define L3_HML3_PM_FILTRBM 0x30C 62 #define L3_HML3_PM_FILTRCM 0x314 63 64 /* Basic counter registers */ 65 #define L3_M_BC_CR 0x500 66 #define L3_M_BC_SATROLL_CR 0x504 67 #define L3_M_BC_CNTENSET 0x508 68 #define L3_M_BC_CNTENCLR 0x50C 69 #define L3_M_BC_INTENSET 0x510 70 #define L3_M_BC_INTENCLR 0x514 71 #define L3_M_BC_GANG 0x718 72 #define L3_M_BC_OVSR 0x740 73 #define L3_M_BC_IRQCTL 0x96C 74 75 /* 76 * Bit field definitions 77 */ 78 79 /* L3_HML3_PM_CR */ 80 #define PM_CR_RESET (0) 81 82 /* L3_HML3_PM_XCNTCTL/L3_HML3_PM_CNTCTLx */ 83 #define PMCNT_RESET (0) 84 85 /* L3_HML3_PM_EVTYPEx */ 86 #define EVSEL(__val) ((__val) & L3_EVTYPE_MASK) 87 88 /* Reset value for all the filter registers */ 89 #define PM_FLTR_RESET (0) 90 91 /* L3_M_BC_CR */ 92 #define BC_RESET (1UL << 1) 93 #define BC_ENABLE (1UL << 0) 94 95 /* L3_M_BC_SATROLL_CR */ 96 #define BC_SATROLL_CR_RESET (0) 97 98 /* L3_M_BC_CNTENSET */ 99 #define PMCNTENSET(__cntr) (1UL << ((__cntr) & 0x7)) 100 101 /* L3_M_BC_CNTENCLR */ 102 #define PMCNTENCLR(__cntr) (1UL << ((__cntr) & 0x7)) 103 #define BC_CNTENCLR_RESET (0xFF) 104 105 /* L3_M_BC_INTENSET */ 106 #define PMINTENSET(__cntr) (1UL << ((__cntr) & 0x7)) 107 108 /* L3_M_BC_INTENCLR */ 109 #define PMINTENCLR(__cntr) (1UL << ((__cntr) & 0x7)) 110 #define BC_INTENCLR_RESET (0xFF) 111 112 /* L3_M_BC_GANG */ 113 #define GANG_EN(__cntr) (1UL << ((__cntr) & 0x7)) 114 #define BC_GANG_RESET (0) 115 116 /* L3_M_BC_OVSR */ 117 #define PMOVSRCLR(__cntr) (1UL << ((__cntr) & 0x7)) 118 #define PMOVSRCLR_RESET (0xFF) 119 120 /* L3_M_BC_IRQCTL */ 121 #define PMIRQONMSBEN(__cntr) (1UL << ((__cntr) & 0x7)) 122 #define BC_IRQCTL_RESET (0x0) 123 124 /* 125 * Events 126 */ 127 128 #define L3_EVENT_CYCLES 0x01 129 #define L3_EVENT_READ_HIT 0x20 130 #define L3_EVENT_READ_MISS 0x21 131 #define L3_EVENT_READ_HIT_D 0x22 132 #define L3_EVENT_READ_MISS_D 0x23 133 #define L3_EVENT_WRITE_HIT 0x24 134 #define L3_EVENT_WRITE_MISS 0x25 135 136 /* 137 * Decoding of settings from perf_event_attr 138 * 139 * The config format for perf events is: 140 * - config: bits 0-7: event type 141 * bit 32: HW counter size requested, 0: 32 bits, 1: 64 bits 142 */ 143 144 static inline u32 get_event_type(struct perf_event *event) 145 { 146 return (event->attr.config) & L3_EVTYPE_MASK; 147 } 148 149 static inline bool event_uses_long_counter(struct perf_event *event) 150 { 151 return !!(event->attr.config & BIT_ULL(L3_EVENT_LC_BIT)); 152 } 153 154 static inline int event_num_counters(struct perf_event *event) 155 { 156 return event_uses_long_counter(event) ? 2 : 1; 157 } 158 159 /* 160 * Main PMU, inherits from the core perf PMU type 161 */ 162 struct l3cache_pmu { 163 struct pmu pmu; 164 struct hlist_node node; 165 void __iomem *regs; 166 struct perf_event *events[L3_NUM_COUNTERS]; 167 unsigned long used_mask[BITS_TO_LONGS(L3_NUM_COUNTERS)]; 168 cpumask_t cpumask; 169 }; 170 171 #define to_l3cache_pmu(p) (container_of(p, struct l3cache_pmu, pmu)) 172 173 /* 174 * Type used to group hardware counter operations 175 * 176 * Used to implement two types of hardware counters, standard (32bits) and 177 * long (64bits). The hardware supports counter chaining which we use to 178 * implement long counters. This support is exposed via the 'lc' flag field 179 * in perf_event_attr.config. 180 */ 181 struct l3cache_event_ops { 182 /* Called to start event monitoring */ 183 void (*start)(struct perf_event *event); 184 /* Called to stop event monitoring */ 185 void (*stop)(struct perf_event *event, int flags); 186 /* Called to update the perf_event */ 187 void (*update)(struct perf_event *event); 188 }; 189 190 /* 191 * Implementation of long counter operations 192 * 193 * 64bit counters are implemented by chaining two of the 32bit physical 194 * counters. The PMU only supports chaining of adjacent even/odd pairs 195 * and for simplicity the driver always configures the odd counter to 196 * count the overflows of the lower-numbered even counter. Note that since 197 * the resulting hardware counter is 64bits no IRQs are required to maintain 198 * the software counter which is also 64bits. 199 */ 200 201 static void qcom_l3_cache__64bit_counter_start(struct perf_event *event) 202 { 203 struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu); 204 int idx = event->hw.idx; 205 u32 evsel = get_event_type(event); 206 u32 gang; 207 208 /* Set the odd counter to count the overflows of the even counter */ 209 gang = readl_relaxed(l3pmu->regs + L3_M_BC_GANG); 210 gang |= GANG_EN(idx + 1); 211 writel_relaxed(gang, l3pmu->regs + L3_M_BC_GANG); 212 213 /* Initialize the hardware counters and reset prev_count*/ 214 local64_set(&event->hw.prev_count, 0); 215 writel_relaxed(0, l3pmu->regs + L3_HML3_PM_EVCNTR(idx + 1)); 216 writel_relaxed(0, l3pmu->regs + L3_HML3_PM_EVCNTR(idx)); 217 218 /* 219 * Set the event types, the upper half must use zero and the lower 220 * half the actual event type 221 */ 222 writel_relaxed(EVSEL(0), l3pmu->regs + L3_HML3_PM_EVTYPE(idx + 1)); 223 writel_relaxed(EVSEL(evsel), l3pmu->regs + L3_HML3_PM_EVTYPE(idx)); 224 225 /* Finally, enable the counters */ 226 writel_relaxed(PMCNT_RESET, l3pmu->regs + L3_HML3_PM_CNTCTL(idx + 1)); 227 writel_relaxed(PMCNTENSET(idx + 1), l3pmu->regs + L3_M_BC_CNTENSET); 228 writel_relaxed(PMCNT_RESET, l3pmu->regs + L3_HML3_PM_CNTCTL(idx)); 229 writel_relaxed(PMCNTENSET(idx), l3pmu->regs + L3_M_BC_CNTENSET); 230 } 231 232 static void qcom_l3_cache__64bit_counter_stop(struct perf_event *event, 233 int flags) 234 { 235 struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu); 236 int idx = event->hw.idx; 237 u32 gang = readl_relaxed(l3pmu->regs + L3_M_BC_GANG); 238 239 /* Disable the counters */ 240 writel_relaxed(PMCNTENCLR(idx), l3pmu->regs + L3_M_BC_CNTENCLR); 241 writel_relaxed(PMCNTENCLR(idx + 1), l3pmu->regs + L3_M_BC_CNTENCLR); 242 243 /* Disable chaining */ 244 writel_relaxed(gang & ~GANG_EN(idx + 1), l3pmu->regs + L3_M_BC_GANG); 245 } 246 247 static void qcom_l3_cache__64bit_counter_update(struct perf_event *event) 248 { 249 struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu); 250 int idx = event->hw.idx; 251 u32 hi, lo; 252 u64 prev, new; 253 254 do { 255 prev = local64_read(&event->hw.prev_count); 256 do { 257 hi = readl_relaxed(l3pmu->regs + L3_HML3_PM_EVCNTR(idx + 1)); 258 lo = readl_relaxed(l3pmu->regs + L3_HML3_PM_EVCNTR(idx)); 259 } while (hi != readl_relaxed(l3pmu->regs + L3_HML3_PM_EVCNTR(idx + 1))); 260 new = ((u64)hi << 32) | lo; 261 } while (local64_cmpxchg(&event->hw.prev_count, prev, new) != prev); 262 263 local64_add(new - prev, &event->count); 264 } 265 266 static const struct l3cache_event_ops event_ops_long = { 267 .start = qcom_l3_cache__64bit_counter_start, 268 .stop = qcom_l3_cache__64bit_counter_stop, 269 .update = qcom_l3_cache__64bit_counter_update, 270 }; 271 272 /* 273 * Implementation of standard counter operations 274 * 275 * 32bit counters use a single physical counter and a hardware feature that 276 * asserts the overflow IRQ on the toggling of the most significant bit in 277 * the counter. This feature allows the counters to be left free-running 278 * without needing the usual reprogramming required to properly handle races 279 * during concurrent calls to update. 280 */ 281 282 static void qcom_l3_cache__32bit_counter_start(struct perf_event *event) 283 { 284 struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu); 285 int idx = event->hw.idx; 286 u32 evsel = get_event_type(event); 287 u32 irqctl = readl_relaxed(l3pmu->regs + L3_M_BC_IRQCTL); 288 289 /* Set the counter to assert the overflow IRQ on MSB toggling */ 290 writel_relaxed(irqctl | PMIRQONMSBEN(idx), l3pmu->regs + L3_M_BC_IRQCTL); 291 292 /* Initialize the hardware counter and reset prev_count*/ 293 local64_set(&event->hw.prev_count, 0); 294 writel_relaxed(0, l3pmu->regs + L3_HML3_PM_EVCNTR(idx)); 295 296 /* Set the event type */ 297 writel_relaxed(EVSEL(evsel), l3pmu->regs + L3_HML3_PM_EVTYPE(idx)); 298 299 /* Enable interrupt generation by this counter */ 300 writel_relaxed(PMINTENSET(idx), l3pmu->regs + L3_M_BC_INTENSET); 301 302 /* Finally, enable the counter */ 303 writel_relaxed(PMCNT_RESET, l3pmu->regs + L3_HML3_PM_CNTCTL(idx)); 304 writel_relaxed(PMCNTENSET(idx), l3pmu->regs + L3_M_BC_CNTENSET); 305 } 306 307 static void qcom_l3_cache__32bit_counter_stop(struct perf_event *event, 308 int flags) 309 { 310 struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu); 311 int idx = event->hw.idx; 312 u32 irqctl = readl_relaxed(l3pmu->regs + L3_M_BC_IRQCTL); 313 314 /* Disable the counter */ 315 writel_relaxed(PMCNTENCLR(idx), l3pmu->regs + L3_M_BC_CNTENCLR); 316 317 /* Disable interrupt generation by this counter */ 318 writel_relaxed(PMINTENCLR(idx), l3pmu->regs + L3_M_BC_INTENCLR); 319 320 /* Set the counter to not assert the overflow IRQ on MSB toggling */ 321 writel_relaxed(irqctl & ~PMIRQONMSBEN(idx), l3pmu->regs + L3_M_BC_IRQCTL); 322 } 323 324 static void qcom_l3_cache__32bit_counter_update(struct perf_event *event) 325 { 326 struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu); 327 int idx = event->hw.idx; 328 u32 prev, new; 329 330 do { 331 prev = local64_read(&event->hw.prev_count); 332 new = readl_relaxed(l3pmu->regs + L3_HML3_PM_EVCNTR(idx)); 333 } while (local64_cmpxchg(&event->hw.prev_count, prev, new) != prev); 334 335 local64_add(new - prev, &event->count); 336 } 337 338 static const struct l3cache_event_ops event_ops_std = { 339 .start = qcom_l3_cache__32bit_counter_start, 340 .stop = qcom_l3_cache__32bit_counter_stop, 341 .update = qcom_l3_cache__32bit_counter_update, 342 }; 343 344 /* Retrieve the appropriate operations for the given event */ 345 static 346 const struct l3cache_event_ops *l3cache_event_get_ops(struct perf_event *event) 347 { 348 if (event_uses_long_counter(event)) 349 return &event_ops_long; 350 else 351 return &event_ops_std; 352 } 353 354 /* 355 * Top level PMU functions. 356 */ 357 358 static inline void qcom_l3_cache__init(struct l3cache_pmu *l3pmu) 359 { 360 int i; 361 362 writel_relaxed(BC_RESET, l3pmu->regs + L3_M_BC_CR); 363 364 /* 365 * Use writel for the first programming command to ensure the basic 366 * counter unit is stopped before proceeding 367 */ 368 writel(BC_SATROLL_CR_RESET, l3pmu->regs + L3_M_BC_SATROLL_CR); 369 370 writel_relaxed(BC_CNTENCLR_RESET, l3pmu->regs + L3_M_BC_CNTENCLR); 371 writel_relaxed(BC_INTENCLR_RESET, l3pmu->regs + L3_M_BC_INTENCLR); 372 writel_relaxed(PMOVSRCLR_RESET, l3pmu->regs + L3_M_BC_OVSR); 373 writel_relaxed(BC_GANG_RESET, l3pmu->regs + L3_M_BC_GANG); 374 writel_relaxed(BC_IRQCTL_RESET, l3pmu->regs + L3_M_BC_IRQCTL); 375 writel_relaxed(PM_CR_RESET, l3pmu->regs + L3_HML3_PM_CR); 376 377 for (i = 0; i < L3_NUM_COUNTERS; ++i) { 378 writel_relaxed(PMCNT_RESET, l3pmu->regs + L3_HML3_PM_CNTCTL(i)); 379 writel_relaxed(EVSEL(0), l3pmu->regs + L3_HML3_PM_EVTYPE(i)); 380 } 381 382 writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRA); 383 writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRAM); 384 writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRB); 385 writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRBM); 386 writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRC); 387 writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRCM); 388 389 /* 390 * Use writel here to ensure all programming commands are done 391 * before proceeding 392 */ 393 writel(BC_ENABLE, l3pmu->regs + L3_M_BC_CR); 394 } 395 396 static irqreturn_t qcom_l3_cache__handle_irq(int irq_num, void *data) 397 { 398 struct l3cache_pmu *l3pmu = data; 399 /* Read the overflow status register */ 400 long status = readl_relaxed(l3pmu->regs + L3_M_BC_OVSR); 401 int idx; 402 403 if (status == 0) 404 return IRQ_NONE; 405 406 /* Clear the bits we read on the overflow status register */ 407 writel_relaxed(status, l3pmu->regs + L3_M_BC_OVSR); 408 409 for_each_set_bit(idx, &status, L3_NUM_COUNTERS) { 410 struct perf_event *event; 411 const struct l3cache_event_ops *ops; 412 413 event = l3pmu->events[idx]; 414 if (!event) 415 continue; 416 417 /* 418 * Since the IRQ is not enabled for events using long counters 419 * we should never see one of those here, however, be consistent 420 * and use the ops indirections like in the other operations. 421 */ 422 423 ops = l3cache_event_get_ops(event); 424 ops->update(event); 425 } 426 427 return IRQ_HANDLED; 428 } 429 430 /* 431 * Implementation of abstract pmu functionality required by 432 * the core perf events code. 433 */ 434 435 static void qcom_l3_cache__pmu_enable(struct pmu *pmu) 436 { 437 struct l3cache_pmu *l3pmu = to_l3cache_pmu(pmu); 438 439 /* Ensure the other programming commands are observed before enabling */ 440 wmb(); 441 442 writel_relaxed(BC_ENABLE, l3pmu->regs + L3_M_BC_CR); 443 } 444 445 static void qcom_l3_cache__pmu_disable(struct pmu *pmu) 446 { 447 struct l3cache_pmu *l3pmu = to_l3cache_pmu(pmu); 448 449 writel_relaxed(0, l3pmu->regs + L3_M_BC_CR); 450 451 /* Ensure the basic counter unit is stopped before proceeding */ 452 wmb(); 453 } 454 455 /* 456 * We must NOT create groups containing events from multiple hardware PMUs, 457 * although mixing different software and hardware PMUs is allowed. 458 */ 459 static bool qcom_l3_cache__validate_event_group(struct perf_event *event) 460 { 461 struct perf_event *leader = event->group_leader; 462 struct perf_event *sibling; 463 int counters = 0; 464 465 if (leader->pmu != event->pmu && !is_software_event(leader)) 466 return false; 467 468 counters = event_num_counters(event); 469 counters += event_num_counters(leader); 470 471 for_each_sibling_event(sibling, leader) { 472 if (is_software_event(sibling)) 473 continue; 474 if (sibling->pmu != event->pmu) 475 return false; 476 counters += event_num_counters(sibling); 477 } 478 479 /* 480 * If the group requires more counters than the HW has, it 481 * cannot ever be scheduled. 482 */ 483 return counters <= L3_NUM_COUNTERS; 484 } 485 486 static int qcom_l3_cache__event_init(struct perf_event *event) 487 { 488 struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu); 489 struct hw_perf_event *hwc = &event->hw; 490 491 /* 492 * Is the event for this PMU? 493 */ 494 if (event->attr.type != event->pmu->type) 495 return -ENOENT; 496 497 /* 498 * There are no per-counter mode filters in the PMU. 499 */ 500 if (event->attr.exclude_user || event->attr.exclude_kernel || 501 event->attr.exclude_hv || event->attr.exclude_idle) 502 return -EINVAL; 503 504 /* 505 * Sampling not supported since these events are not core-attributable. 506 */ 507 if (hwc->sample_period) 508 return -EINVAL; 509 510 /* 511 * Task mode not available, we run the counters as socket counters, 512 * not attributable to any CPU and therefore cannot attribute per-task. 513 */ 514 if (event->cpu < 0) 515 return -EINVAL; 516 517 /* Validate the group */ 518 if (!qcom_l3_cache__validate_event_group(event)) 519 return -EINVAL; 520 521 hwc->idx = -1; 522 523 /* 524 * Many perf core operations (eg. events rotation) operate on a 525 * single CPU context. This is obvious for CPU PMUs, where one 526 * expects the same sets of events being observed on all CPUs, 527 * but can lead to issues for off-core PMUs, like this one, where 528 * each event could be theoretically assigned to a different CPU. 529 * To mitigate this, we enforce CPU assignment to one designated 530 * processor (the one described in the "cpumask" attribute exported 531 * by the PMU device). perf user space tools honor this and avoid 532 * opening more than one copy of the events. 533 */ 534 event->cpu = cpumask_first(&l3pmu->cpumask); 535 536 return 0; 537 } 538 539 static void qcom_l3_cache__event_start(struct perf_event *event, int flags) 540 { 541 struct hw_perf_event *hwc = &event->hw; 542 const struct l3cache_event_ops *ops = l3cache_event_get_ops(event); 543 544 hwc->state = 0; 545 ops->start(event); 546 } 547 548 static void qcom_l3_cache__event_stop(struct perf_event *event, int flags) 549 { 550 struct hw_perf_event *hwc = &event->hw; 551 const struct l3cache_event_ops *ops = l3cache_event_get_ops(event); 552 553 if (hwc->state & PERF_HES_STOPPED) 554 return; 555 556 ops->stop(event, flags); 557 if (flags & PERF_EF_UPDATE) 558 ops->update(event); 559 hwc->state |= PERF_HES_STOPPED | PERF_HES_UPTODATE; 560 } 561 562 static int qcom_l3_cache__event_add(struct perf_event *event, int flags) 563 { 564 struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu); 565 struct hw_perf_event *hwc = &event->hw; 566 int order = event_uses_long_counter(event) ? 1 : 0; 567 int idx; 568 569 /* 570 * Try to allocate a counter. 571 */ 572 idx = bitmap_find_free_region(l3pmu->used_mask, L3_NUM_COUNTERS, order); 573 if (idx < 0) 574 /* The counters are all in use. */ 575 return -EAGAIN; 576 577 hwc->idx = idx; 578 hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE; 579 l3pmu->events[idx] = event; 580 581 if (flags & PERF_EF_START) 582 qcom_l3_cache__event_start(event, 0); 583 584 /* Propagate changes to the userspace mapping. */ 585 perf_event_update_userpage(event); 586 587 return 0; 588 } 589 590 static void qcom_l3_cache__event_del(struct perf_event *event, int flags) 591 { 592 struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu); 593 struct hw_perf_event *hwc = &event->hw; 594 int order = event_uses_long_counter(event) ? 1 : 0; 595 596 /* Stop and clean up */ 597 qcom_l3_cache__event_stop(event, flags | PERF_EF_UPDATE); 598 l3pmu->events[hwc->idx] = NULL; 599 bitmap_release_region(l3pmu->used_mask, hwc->idx, order); 600 601 /* Propagate changes to the userspace mapping. */ 602 perf_event_update_userpage(event); 603 } 604 605 static void qcom_l3_cache__event_read(struct perf_event *event) 606 { 607 const struct l3cache_event_ops *ops = l3cache_event_get_ops(event); 608 609 ops->update(event); 610 } 611 612 /* 613 * Add sysfs attributes 614 * 615 * We export: 616 * - formats, used by perf user space and other tools to configure events 617 * - events, used by perf user space and other tools to create events 618 * symbolically, e.g.: 619 * perf stat -a -e l3cache_0_0/event=read-miss/ ls 620 * perf stat -a -e l3cache_0_0/event=0x21/ ls 621 * - cpumask, used by perf user space and other tools to know on which CPUs 622 * to open the events 623 */ 624 625 /* formats */ 626 627 static ssize_t l3cache_pmu_format_show(struct device *dev, 628 struct device_attribute *attr, char *buf) 629 { 630 struct dev_ext_attribute *eattr; 631 632 eattr = container_of(attr, struct dev_ext_attribute, attr); 633 return sprintf(buf, "%s\n", (char *) eattr->var); 634 } 635 636 #define L3CACHE_PMU_FORMAT_ATTR(_name, _config) \ 637 (&((struct dev_ext_attribute[]) { \ 638 { .attr = __ATTR(_name, 0444, l3cache_pmu_format_show, NULL), \ 639 .var = (void *) _config, } \ 640 })[0].attr.attr) 641 642 static struct attribute *qcom_l3_cache_pmu_formats[] = { 643 L3CACHE_PMU_FORMAT_ATTR(event, "config:0-7"), 644 L3CACHE_PMU_FORMAT_ATTR(lc, "config:" __stringify(L3_EVENT_LC_BIT)), 645 NULL, 646 }; 647 648 static struct attribute_group qcom_l3_cache_pmu_format_group = { 649 .name = "format", 650 .attrs = qcom_l3_cache_pmu_formats, 651 }; 652 653 /* events */ 654 655 static ssize_t l3cache_pmu_event_show(struct device *dev, 656 struct device_attribute *attr, char *page) 657 { 658 struct perf_pmu_events_attr *pmu_attr; 659 660 pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr); 661 return sprintf(page, "event=0x%02llx\n", pmu_attr->id); 662 } 663 664 #define L3CACHE_EVENT_ATTR(_name, _id) \ 665 (&((struct perf_pmu_events_attr[]) { \ 666 { .attr = __ATTR(_name, 0444, l3cache_pmu_event_show, NULL), \ 667 .id = _id, } \ 668 })[0].attr.attr) 669 670 static struct attribute *qcom_l3_cache_pmu_events[] = { 671 L3CACHE_EVENT_ATTR(cycles, L3_EVENT_CYCLES), 672 L3CACHE_EVENT_ATTR(read-hit, L3_EVENT_READ_HIT), 673 L3CACHE_EVENT_ATTR(read-miss, L3_EVENT_READ_MISS), 674 L3CACHE_EVENT_ATTR(read-hit-d-side, L3_EVENT_READ_HIT_D), 675 L3CACHE_EVENT_ATTR(read-miss-d-side, L3_EVENT_READ_MISS_D), 676 L3CACHE_EVENT_ATTR(write-hit, L3_EVENT_WRITE_HIT), 677 L3CACHE_EVENT_ATTR(write-miss, L3_EVENT_WRITE_MISS), 678 NULL 679 }; 680 681 static struct attribute_group qcom_l3_cache_pmu_events_group = { 682 .name = "events", 683 .attrs = qcom_l3_cache_pmu_events, 684 }; 685 686 /* cpumask */ 687 688 static ssize_t qcom_l3_cache_pmu_cpumask_show(struct device *dev, 689 struct device_attribute *attr, char *buf) 690 { 691 struct l3cache_pmu *l3pmu = to_l3cache_pmu(dev_get_drvdata(dev)); 692 693 return cpumap_print_to_pagebuf(true, buf, &l3pmu->cpumask); 694 } 695 696 static DEVICE_ATTR(cpumask, 0444, qcom_l3_cache_pmu_cpumask_show, NULL); 697 698 static struct attribute *qcom_l3_cache_pmu_cpumask_attrs[] = { 699 &dev_attr_cpumask.attr, 700 NULL, 701 }; 702 703 static struct attribute_group qcom_l3_cache_pmu_cpumask_attr_group = { 704 .attrs = qcom_l3_cache_pmu_cpumask_attrs, 705 }; 706 707 /* 708 * Per PMU device attribute groups 709 */ 710 static const struct attribute_group *qcom_l3_cache_pmu_attr_grps[] = { 711 &qcom_l3_cache_pmu_format_group, 712 &qcom_l3_cache_pmu_events_group, 713 &qcom_l3_cache_pmu_cpumask_attr_group, 714 NULL, 715 }; 716 717 /* 718 * Probing functions and data. 719 */ 720 721 static int qcom_l3_cache_pmu_online_cpu(unsigned int cpu, struct hlist_node *node) 722 { 723 struct l3cache_pmu *l3pmu = hlist_entry_safe(node, struct l3cache_pmu, node); 724 725 /* If there is not a CPU/PMU association pick this CPU */ 726 if (cpumask_empty(&l3pmu->cpumask)) 727 cpumask_set_cpu(cpu, &l3pmu->cpumask); 728 729 return 0; 730 } 731 732 static int qcom_l3_cache_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node) 733 { 734 struct l3cache_pmu *l3pmu = hlist_entry_safe(node, struct l3cache_pmu, node); 735 unsigned int target; 736 737 if (!cpumask_test_and_clear_cpu(cpu, &l3pmu->cpumask)) 738 return 0; 739 target = cpumask_any_but(cpu_online_mask, cpu); 740 if (target >= nr_cpu_ids) 741 return 0; 742 perf_pmu_migrate_context(&l3pmu->pmu, cpu, target); 743 cpumask_set_cpu(target, &l3pmu->cpumask); 744 return 0; 745 } 746 747 static int qcom_l3_cache_pmu_probe(struct platform_device *pdev) 748 { 749 struct l3cache_pmu *l3pmu; 750 struct acpi_device *acpi_dev; 751 struct resource *memrc; 752 int ret; 753 char *name; 754 755 /* Initialize the PMU data structures */ 756 757 acpi_dev = ACPI_COMPANION(&pdev->dev); 758 if (!acpi_dev) 759 return -ENODEV; 760 761 l3pmu = devm_kzalloc(&pdev->dev, sizeof(*l3pmu), GFP_KERNEL); 762 name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "l3cache_%s_%s", 763 acpi_dev->parent->pnp.unique_id, acpi_dev->pnp.unique_id); 764 if (!l3pmu || !name) 765 return -ENOMEM; 766 767 l3pmu->pmu = (struct pmu) { 768 .task_ctx_nr = perf_invalid_context, 769 770 .pmu_enable = qcom_l3_cache__pmu_enable, 771 .pmu_disable = qcom_l3_cache__pmu_disable, 772 .event_init = qcom_l3_cache__event_init, 773 .add = qcom_l3_cache__event_add, 774 .del = qcom_l3_cache__event_del, 775 .start = qcom_l3_cache__event_start, 776 .stop = qcom_l3_cache__event_stop, 777 .read = qcom_l3_cache__event_read, 778 779 .attr_groups = qcom_l3_cache_pmu_attr_grps, 780 }; 781 782 memrc = platform_get_resource(pdev, IORESOURCE_MEM, 0); 783 l3pmu->regs = devm_ioremap_resource(&pdev->dev, memrc); 784 if (IS_ERR(l3pmu->regs)) { 785 dev_err(&pdev->dev, "Can't map PMU @%pa\n", &memrc->start); 786 return PTR_ERR(l3pmu->regs); 787 } 788 789 qcom_l3_cache__init(l3pmu); 790 791 ret = platform_get_irq(pdev, 0); 792 if (ret <= 0) 793 return ret; 794 795 ret = devm_request_irq(&pdev->dev, ret, qcom_l3_cache__handle_irq, 0, 796 name, l3pmu); 797 if (ret) { 798 dev_err(&pdev->dev, "Request for IRQ failed for slice @%pa\n", 799 &memrc->start); 800 return ret; 801 } 802 803 /* Add this instance to the list used by the offline callback */ 804 ret = cpuhp_state_add_instance(CPUHP_AP_PERF_ARM_QCOM_L3_ONLINE, &l3pmu->node); 805 if (ret) { 806 dev_err(&pdev->dev, "Error %d registering hotplug", ret); 807 return ret; 808 } 809 810 ret = perf_pmu_register(&l3pmu->pmu, name, -1); 811 if (ret < 0) { 812 dev_err(&pdev->dev, "Failed to register L3 cache PMU (%d)\n", ret); 813 return ret; 814 } 815 816 dev_info(&pdev->dev, "Registered %s, type: %d\n", name, l3pmu->pmu.type); 817 818 return 0; 819 } 820 821 static const struct acpi_device_id qcom_l3_cache_pmu_acpi_match[] = { 822 { "QCOM8081", }, 823 { } 824 }; 825 MODULE_DEVICE_TABLE(acpi, qcom_l3_cache_pmu_acpi_match); 826 827 static struct platform_driver qcom_l3_cache_pmu_driver = { 828 .driver = { 829 .name = "qcom-l3cache-pmu", 830 .acpi_match_table = ACPI_PTR(qcom_l3_cache_pmu_acpi_match), 831 }, 832 .probe = qcom_l3_cache_pmu_probe, 833 }; 834 835 static int __init register_qcom_l3_cache_pmu_driver(void) 836 { 837 int ret; 838 839 /* Install a hook to update the reader CPU in case it goes offline */ 840 ret = cpuhp_setup_state_multi(CPUHP_AP_PERF_ARM_QCOM_L3_ONLINE, 841 "perf/qcom/l3cache:online", 842 qcom_l3_cache_pmu_online_cpu, 843 qcom_l3_cache_pmu_offline_cpu); 844 if (ret) 845 return ret; 846 847 return platform_driver_register(&qcom_l3_cache_pmu_driver); 848 } 849 device_initcall(register_qcom_l3_cache_pmu_driver); 850