drivers/perf/fsl_imx8_ddr_perf.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright 2017 NXP
   4  * Copyright 2016 Freescale Semiconductor, Inc.
   5  */
   6
   7 #include <linux/bitfield.h>
   8 #include <linux/init.h>
   9 #include <linux/interrupt.h>
  10 #include <linux/io.h>
  11 #include <linux/module.h>
  12 #include <linux/of.h>
  13 #include <linux/of_address.h>
  14 #include <linux/of_device.h>
  15 #include <linux/of_irq.h>
  16 #include <linux/perf_event.h>
  17 #include <linux/slab.h>
  18
  19 #define COUNTER_CNTL            0x0
  20 #define COUNTER_READ            0x20
  21
  22 #define COUNTER_DPCR1           0x30
  23
  24 #define CNTL_OVER               0x1
  25 #define CNTL_CLEAR              0x2
  26 #define CNTL_EN                 0x4
  27 #define CNTL_EN_MASK            0xFFFFFFFB
  28 #define CNTL_CLEAR_MASK         0xFFFFFFFD
  29 #define CNTL_OVER_MASK          0xFFFFFFFE
  30
  31 #define CNTL_CSV_SHIFT          24
  32 #define CNTL_CSV_MASK           (0xFFU << CNTL_CSV_SHIFT)
  33
  34 #define EVENT_CYCLES_ID         0
  35 #define EVENT_CYCLES_COUNTER    0
  36 #define NUM_COUNTERS            4
  37
  38 #define AXI_MASKING_REVERT      0xffff0000      /* AXI_MASKING(MSB 16bits) + AXI_ID(LSB 16bits) */
  39
  40 #define to_ddr_pmu(p)           container_of(p, struct ddr_pmu, pmu)
  41
  42 #define DDR_PERF_DEV_NAME       "imx8_ddr"
  43 #define DDR_CPUHP_CB_NAME       DDR_PERF_DEV_NAME "_perf_pmu"
  44
  45 static DEFINE_IDA(ddr_ida);
  46
  47 /* DDR Perf hardware feature */
  48 #define DDR_CAP_AXI_ID_FILTER                   0x1     /* support AXI ID filter */
  49 #define DDR_CAP_AXI_ID_FILTER_ENHANCED          0x3     /* support enhanced AXI ID filter */
  50
  51 struct fsl_ddr_devtype_data {
  52         unsigned int quirks;    /* quirks needed for different DDR Perf core */
  53         const char *identifier; /* system PMU identifier for userspace */
  54 };
  55
  56 static const struct fsl_ddr_devtype_data imx8_devtype_data;
  57
  58 static const struct fsl_ddr_devtype_data imx8m_devtype_data = {
  59         .quirks = DDR_CAP_AXI_ID_FILTER,
  60 };
  61
  62 static const struct fsl_ddr_devtype_data imx8mq_devtype_data = {
  63         .quirks = DDR_CAP_AXI_ID_FILTER,
  64         .identifier = "i.MX8MQ",
  65 };
  66
  67 static const struct fsl_ddr_devtype_data imx8mm_devtype_data = {
  68         .quirks = DDR_CAP_AXI_ID_FILTER,
  69         .identifier = "i.MX8MM",
  70 };
  71
  72 static const struct fsl_ddr_devtype_data imx8mn_devtype_data = {
  73         .quirks = DDR_CAP_AXI_ID_FILTER,
  74         .identifier = "i.MX8MN",
  75 };
  76
  77 static const struct fsl_ddr_devtype_data imx8mp_devtype_data = {
  78         .quirks = DDR_CAP_AXI_ID_FILTER_ENHANCED,
  79         .identifier = "i.MX8MP",
  80 };
  81
  82 static const struct of_device_id imx_ddr_pmu_dt_ids[] = {
  83         { .compatible = "fsl,imx8-ddr-pmu", .data = &imx8_devtype_data},
  84         { .compatible = "fsl,imx8m-ddr-pmu", .data = &imx8m_devtype_data},
  85         { .compatible = "fsl,imx8mq-ddr-pmu", .data = &imx8mq_devtype_data},
  86         { .compatible = "fsl,imx8mm-ddr-pmu", .data = &imx8mm_devtype_data},
  87         { .compatible = "fsl,imx8mn-ddr-pmu", .data = &imx8mn_devtype_data},
  88         { .compatible = "fsl,imx8mp-ddr-pmu", .data = &imx8mp_devtype_data},
  89         { /* sentinel */ }
  90 };
  91 MODULE_DEVICE_TABLE(of, imx_ddr_pmu_dt_ids);
  92
  93 struct ddr_pmu {
  94         struct pmu pmu;
  95         void __iomem *base;
  96         unsigned int cpu;
  97         struct  hlist_node node;
  98         struct  device *dev;
  99         struct perf_event *events[NUM_COUNTERS];
 100         int active_events;
 101         enum cpuhp_state cpuhp_state;
 102         const struct fsl_ddr_devtype_data *devtype_data;
 103         int irq;
 104         int id;
 105 };
 106
 107 static ssize_t ddr_perf_identifier_show(struct device *dev,
 108                                         struct device_attribute *attr,
 109                                         char *page)
 110 {
 111         struct ddr_pmu *pmu = dev_get_drvdata(dev);
 112
 113         return sysfs_emit(page, "%s\n", pmu->devtype_data->identifier);
 114 }
 115
 116 static umode_t ddr_perf_identifier_attr_visible(struct kobject *kobj,
 117                                                 struct attribute *attr,
 118                                                 int n)
 119 {
 120         struct device *dev = kobj_to_dev(kobj);
 121         struct ddr_pmu *pmu = dev_get_drvdata(dev);
 122
 123         if (!pmu->devtype_data->identifier)
 124                 return 0;
 125         return attr->mode;
 126 };
 127
 128 static struct device_attribute ddr_perf_identifier_attr =
 129         __ATTR(identifier, 0444, ddr_perf_identifier_show, NULL);
 130
 131 static struct attribute *ddr_perf_identifier_attrs[] = {
 132         &ddr_perf_identifier_attr.attr,
 133         NULL,
 134 };
 135
 136 static const struct attribute_group ddr_perf_identifier_attr_group = {
 137         .attrs = ddr_perf_identifier_attrs,
 138         .is_visible = ddr_perf_identifier_attr_visible,
 139 };
 140
 141 enum ddr_perf_filter_capabilities {
 142         PERF_CAP_AXI_ID_FILTER = 0,
 143         PERF_CAP_AXI_ID_FILTER_ENHANCED,
 144         PERF_CAP_AXI_ID_FEAT_MAX,
 145 };
 146
 147 static u32 ddr_perf_filter_cap_get(struct ddr_pmu *pmu, int cap)
 148 {
 149         u32 quirks = pmu->devtype_data->quirks;
 150
 151         switch (cap) {
 152         case PERF_CAP_AXI_ID_FILTER:
 153                 return !!(quirks & DDR_CAP_AXI_ID_FILTER);
 154         case PERF_CAP_AXI_ID_FILTER_ENHANCED:
 155                 quirks &= DDR_CAP_AXI_ID_FILTER_ENHANCED;
 156                 return quirks == DDR_CAP_AXI_ID_FILTER_ENHANCED;
 157         default:
 158                 WARN(1, "unknown filter cap %d\n", cap);
 159         }
 160
 161         return 0;
 162 }
 163
 164 static ssize_t ddr_perf_filter_cap_show(struct device *dev,
 165                                         struct device_attribute *attr,
 166                                         char *buf)
 167 {
 168         struct ddr_pmu *pmu = dev_get_drvdata(dev);
 169         struct dev_ext_attribute *ea =
 170                 container_of(attr, struct dev_ext_attribute, attr);
 171         int cap = (long)ea->var;
 172
 173         return sysfs_emit(buf, "%u\n", ddr_perf_filter_cap_get(pmu, cap));
 174 }
 175
 176 #define PERF_EXT_ATTR_ENTRY(_name, _func, _var)                         \
 177         (&((struct dev_ext_attribute) {                                 \
 178                 __ATTR(_name, 0444, _func, NULL), (void *)_var          \
 179         }).attr.attr)
 180
 181 #define PERF_FILTER_EXT_ATTR_ENTRY(_name, _var)                         \
 182         PERF_EXT_ATTR_ENTRY(_name, ddr_perf_filter_cap_show, _var)
 183
 184 static struct attribute *ddr_perf_filter_cap_attr[] = {
 185         PERF_FILTER_EXT_ATTR_ENTRY(filter, PERF_CAP_AXI_ID_FILTER),
 186         PERF_FILTER_EXT_ATTR_ENTRY(enhanced_filter, PERF_CAP_AXI_ID_FILTER_ENHANCED),
 187         NULL,
 188 };
 189
 190 static const struct attribute_group ddr_perf_filter_cap_attr_group = {
 191         .name = "caps",
 192         .attrs = ddr_perf_filter_cap_attr,
 193 };
 194
 195 static ssize_t ddr_perf_cpumask_show(struct device *dev,
 196                                 struct device_attribute *attr, char *buf)
 197 {
 198         struct ddr_pmu *pmu = dev_get_drvdata(dev);
 199
 200         return cpumap_print_to_pagebuf(true, buf, cpumask_of(pmu->cpu));
 201 }
 202
 203 static struct device_attribute ddr_perf_cpumask_attr =
 204         __ATTR(cpumask, 0444, ddr_perf_cpumask_show, NULL);
 205
 206 static struct attribute *ddr_perf_cpumask_attrs[] = {
 207         &ddr_perf_cpumask_attr.attr,
 208         NULL,
 209 };
 210
 211 static const struct attribute_group ddr_perf_cpumask_attr_group = {
 212         .attrs = ddr_perf_cpumask_attrs,
 213 };
 214
 215 static ssize_t
 216 ddr_pmu_event_show(struct device *dev, struct device_attribute *attr,
 217                    char *page)
 218 {
 219         struct perf_pmu_events_attr *pmu_attr;
 220
 221         pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr);
 222         return sysfs_emit(page, "event=0x%02llx\n", pmu_attr->id);
 223 }
 224
 225 #define IMX8_DDR_PMU_EVENT_ATTR(_name, _id)             \
 226         PMU_EVENT_ATTR_ID(_name, ddr_pmu_event_show, _id)
 227
 228 static struct attribute *ddr_perf_events_attrs[] = {
 229         IMX8_DDR_PMU_EVENT_ATTR(cycles, EVENT_CYCLES_ID),
 230         IMX8_DDR_PMU_EVENT_ATTR(selfresh, 0x01),
 231         IMX8_DDR_PMU_EVENT_ATTR(read-accesses, 0x04),
 232         IMX8_DDR_PMU_EVENT_ATTR(write-accesses, 0x05),
 233         IMX8_DDR_PMU_EVENT_ATTR(read-queue-depth, 0x08),
 234         IMX8_DDR_PMU_EVENT_ATTR(write-queue-depth, 0x09),
 235         IMX8_DDR_PMU_EVENT_ATTR(lp-read-credit-cnt, 0x10),
 236         IMX8_DDR_PMU_EVENT_ATTR(hp-read-credit-cnt, 0x11),
 237         IMX8_DDR_PMU_EVENT_ATTR(write-credit-cnt, 0x12),
 238         IMX8_DDR_PMU_EVENT_ATTR(read-command, 0x20),
 239         IMX8_DDR_PMU_EVENT_ATTR(write-command, 0x21),
 240         IMX8_DDR_PMU_EVENT_ATTR(read-modify-write-command, 0x22),
 241         IMX8_DDR_PMU_EVENT_ATTR(hp-read, 0x23),
 242         IMX8_DDR_PMU_EVENT_ATTR(hp-req-nocredit, 0x24),
 243         IMX8_DDR_PMU_EVENT_ATTR(hp-xact-credit, 0x25),
 244         IMX8_DDR_PMU_EVENT_ATTR(lp-req-nocredit, 0x26),
 245         IMX8_DDR_PMU_EVENT_ATTR(lp-xact-credit, 0x27),
 246         IMX8_DDR_PMU_EVENT_ATTR(wr-xact-credit, 0x29),
 247         IMX8_DDR_PMU_EVENT_ATTR(read-cycles, 0x2a),
 248         IMX8_DDR_PMU_EVENT_ATTR(write-cycles, 0x2b),
 249         IMX8_DDR_PMU_EVENT_ATTR(read-write-transition, 0x30),
 250         IMX8_DDR_PMU_EVENT_ATTR(precharge, 0x31),
 251         IMX8_DDR_PMU_EVENT_ATTR(activate, 0x32),
 252         IMX8_DDR_PMU_EVENT_ATTR(load-mode, 0x33),
 253         IMX8_DDR_PMU_EVENT_ATTR(perf-mwr, 0x34),
 254         IMX8_DDR_PMU_EVENT_ATTR(read, 0x35),
 255         IMX8_DDR_PMU_EVENT_ATTR(read-activate, 0x36),
 256         IMX8_DDR_PMU_EVENT_ATTR(refresh, 0x37),
 257         IMX8_DDR_PMU_EVENT_ATTR(write, 0x38),
 258         IMX8_DDR_PMU_EVENT_ATTR(raw-hazard, 0x39),
 259         IMX8_DDR_PMU_EVENT_ATTR(axid-read, 0x41),
 260         IMX8_DDR_PMU_EVENT_ATTR(axid-write, 0x42),
 261         NULL,
 262 };
 263
 264 static const struct attribute_group ddr_perf_events_attr_group = {
 265         .name = "events",
 266         .attrs = ddr_perf_events_attrs,
 267 };
 268
 269 PMU_FORMAT_ATTR(event, "config:0-7");
 270 PMU_FORMAT_ATTR(axi_id, "config1:0-15");
 271 PMU_FORMAT_ATTR(axi_mask, "config1:16-31");
 272
 273 static struct attribute *ddr_perf_format_attrs[] = {
 274         &format_attr_event.attr,
 275         &format_attr_axi_id.attr,
 276         &format_attr_axi_mask.attr,
 277         NULL,
 278 };
 279
 280 static const struct attribute_group ddr_perf_format_attr_group = {
 281         .name = "format",
 282         .attrs = ddr_perf_format_attrs,
 283 };
 284
 285 static const struct attribute_group *attr_groups[] = {
 286         &ddr_perf_events_attr_group,
 287         &ddr_perf_format_attr_group,
 288         &ddr_perf_cpumask_attr_group,
 289         &ddr_perf_filter_cap_attr_group,
 290         &ddr_perf_identifier_attr_group,
 291         NULL,
 292 };
 293
 294 static bool ddr_perf_is_filtered(struct perf_event *event)
 295 {
 296         return event->attr.config == 0x41 || event->attr.config == 0x42;
 297 }
 298
 299 static u32 ddr_perf_filter_val(struct perf_event *event)
 300 {
 301         return event->attr.config1;
 302 }
 303
 304 static bool ddr_perf_filters_compatible(struct perf_event *a,
 305                                         struct perf_event *b)
 306 {
 307         if (!ddr_perf_is_filtered(a))
 308                 return true;
 309         if (!ddr_perf_is_filtered(b))
 310                 return true;
 311         return ddr_perf_filter_val(a) == ddr_perf_filter_val(b);
 312 }
 313
 314 static bool ddr_perf_is_enhanced_filtered(struct perf_event *event)
 315 {
 316         unsigned int filt;
 317         struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
 318
 319         filt = pmu->devtype_data->quirks & DDR_CAP_AXI_ID_FILTER_ENHANCED;
 320         return (filt == DDR_CAP_AXI_ID_FILTER_ENHANCED) &&
 321                 ddr_perf_is_filtered(event);
 322 }
 323
 324 static u32 ddr_perf_alloc_counter(struct ddr_pmu *pmu, int event)
 325 {
 326         int i;
 327
 328         /*
 329          * Always map cycle event to counter 0
 330          * Cycles counter is dedicated for cycle event
 331          * can't used for the other events
 332          */
 333         if (event == EVENT_CYCLES_ID) {
 334                 if (pmu->events[EVENT_CYCLES_COUNTER] == NULL)
 335                         return EVENT_CYCLES_COUNTER;
 336                 else
 337                         return -ENOENT;
 338         }
 339
 340         for (i = 1; i < NUM_COUNTERS; i++) {
 341                 if (pmu->events[i] == NULL)
 342                         return i;
 343         }
 344
 345         return -ENOENT;
 346 }
 347
 348 static void ddr_perf_free_counter(struct ddr_pmu *pmu, int counter)
 349 {
 350         pmu->events[counter] = NULL;
 351 }
 352
 353 static u32 ddr_perf_read_counter(struct ddr_pmu *pmu, int counter)
 354 {
 355         struct perf_event *event = pmu->events[counter];
 356         void __iomem *base = pmu->base;
 357
 358         /*
 359          * return bytes instead of bursts from ddr transaction for
 360          * axid-read and axid-write event if PMU core supports enhanced
 361          * filter.
 362          */
 363         base += ddr_perf_is_enhanced_filtered(event) ? COUNTER_DPCR1 :
 364                                                        COUNTER_READ;
 365         return readl_relaxed(base + counter * 4);
 366 }
 367
 368 static int ddr_perf_event_init(struct perf_event *event)
 369 {
 370         struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
 371         struct hw_perf_event *hwc = &event->hw;
 372         struct perf_event *sibling;
 373
 374         if (event->attr.type != event->pmu->type)
 375                 return -ENOENT;
 376
 377         if (is_sampling_event(event) || event->attach_state & PERF_ATTACH_TASK)
 378                 return -EOPNOTSUPP;
 379
 380         if (event->cpu < 0) {
 381                 dev_warn(pmu->dev, "Can't provide per-task data!\n");
 382                 return -EOPNOTSUPP;
 383         }
 384
 385         /*
 386          * We must NOT create groups containing mixed PMUs, although software
 387          * events are acceptable (for example to create a CCN group
 388          * periodically read when a hrtimer aka cpu-clock leader triggers).
 389          */
 390         if (event->group_leader->pmu != event->pmu &&
 391                         !is_software_event(event->group_leader))
 392                 return -EINVAL;
 393
 394         if (pmu->devtype_data->quirks & DDR_CAP_AXI_ID_FILTER) {
 395                 if (!ddr_perf_filters_compatible(event, event->group_leader))
 396                         return -EINVAL;
 397                 for_each_sibling_event(sibling, event->group_leader) {
 398                         if (!ddr_perf_filters_compatible(event, sibling))
 399                                 return -EINVAL;
 400                 }
 401         }
 402
 403         for_each_sibling_event(sibling, event->group_leader) {
 404                 if (sibling->pmu != event->pmu &&
 405                                 !is_software_event(sibling))
 406                         return -EINVAL;
 407         }
 408
 409         event->cpu = pmu->cpu;
 410         hwc->idx = -1;
 411
 412         return 0;
 413 }
 414
 415 static void ddr_perf_counter_enable(struct ddr_pmu *pmu, int config,
 416                                   int counter, bool enable)
 417 {
 418         u8 reg = counter * 4 + COUNTER_CNTL;
 419         int val;
 420
 421         if (enable) {
 422                 /*
 423                  * cycle counter is special which should firstly write 0 then
 424                  * write 1 into CLEAR bit to clear it. Other counters only
 425                  * need write 0 into CLEAR bit and it turns out to be 1 by
 426                  * hardware. Below enable flow is harmless for all counters.
 427                  */
 428                 writel(0, pmu->base + reg);
 429                 val = CNTL_EN | CNTL_CLEAR;
 430                 val |= FIELD_PREP(CNTL_CSV_MASK, config);
 431                 writel(val, pmu->base + reg);
 432         } else {
 433                 /* Disable counter */
 434                 val = readl_relaxed(pmu->base + reg) & CNTL_EN_MASK;
 435                 writel(val, pmu->base + reg);
 436         }
 437 }
 438
 439 static bool ddr_perf_counter_overflow(struct ddr_pmu *pmu, int counter)
 440 {
 441         int val;
 442
 443         val = readl_relaxed(pmu->base + counter * 4 + COUNTER_CNTL);
 444
 445         return val & CNTL_OVER;
 446 }
 447
 448 static void ddr_perf_counter_clear(struct ddr_pmu *pmu, int counter)
 449 {
 450         u8 reg = counter * 4 + COUNTER_CNTL;
 451         int val;
 452
 453         val = readl_relaxed(pmu->base + reg);
 454         val &= ~CNTL_CLEAR;
 455         writel(val, pmu->base + reg);
 456
 457         val |= CNTL_CLEAR;
 458         writel(val, pmu->base + reg);
 459 }
 460
 461 static void ddr_perf_event_update(struct perf_event *event)
 462 {
 463         struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
 464         struct hw_perf_event *hwc = &event->hw;
 465         u64 new_raw_count;
 466         int counter = hwc->idx;
 467         int ret;
 468
 469         new_raw_count = ddr_perf_read_counter(pmu, counter);
 470         local64_add(new_raw_count, &event->count);
 471
 472         /*
 473          * For legacy SoCs: event counter continue counting when overflow,
 474          *                  no need to clear the counter.
 475          * For new SoCs: event counter stop counting when overflow, need
 476          *               clear counter to let it count again.
 477          */
 478         if (counter != EVENT_CYCLES_COUNTER) {
 479                 ret = ddr_perf_counter_overflow(pmu, counter);
 480                 if (ret)
 481                         dev_warn_ratelimited(pmu->dev,  "events lost due to counter overflow (config 0x%llx)\n",
 482                                              event->attr.config);
 483         }
 484
 485         /* clear counter every time for both cycle counter and event counter */
 486         ddr_perf_counter_clear(pmu, counter);
 487 }
 488
 489 static void ddr_perf_event_start(struct perf_event *event, int flags)
 490 {
 491         struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
 492         struct hw_perf_event *hwc = &event->hw;
 493         int counter = hwc->idx;
 494
 495         local64_set(&hwc->prev_count, 0);
 496
 497         ddr_perf_counter_enable(pmu, event->attr.config, counter, true);
 498
 499         hwc->state = 0;
 500 }
 501
 502 static int ddr_perf_event_add(struct perf_event *event, int flags)
 503 {
 504         struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
 505         struct hw_perf_event *hwc = &event->hw;
 506         int counter;
 507         int cfg = event->attr.config;
 508         int cfg1 = event->attr.config1;
 509
 510         if (pmu->devtype_data->quirks & DDR_CAP_AXI_ID_FILTER) {
 511                 int i;
 512
 513                 for (i = 1; i < NUM_COUNTERS; i++) {
 514                         if (pmu->events[i] &&
 515                             !ddr_perf_filters_compatible(event, pmu->events[i]))
 516                                 return -EINVAL;
 517                 }
 518
 519                 if (ddr_perf_is_filtered(event)) {
 520                         /* revert axi id masking(axi_mask) value */
 521                         cfg1 ^= AXI_MASKING_REVERT;
 522                         writel(cfg1, pmu->base + COUNTER_DPCR1);
 523                 }
 524         }
 525
 526         counter = ddr_perf_alloc_counter(pmu, cfg);
 527         if (counter < 0) {
 528                 dev_dbg(pmu->dev, "There are not enough counters\n");
 529                 return -EOPNOTSUPP;
 530         }
 531
 532         pmu->events[counter] = event;
 533         pmu->active_events++;
 534         hwc->idx = counter;
 535
 536         hwc->state |= PERF_HES_STOPPED;
 537
 538         if (flags & PERF_EF_START)
 539                 ddr_perf_event_start(event, flags);
 540
 541         return 0;
 542 }
 543
 544 static void ddr_perf_event_stop(struct perf_event *event, int flags)
 545 {
 546         struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
 547         struct hw_perf_event *hwc = &event->hw;
 548         int counter = hwc->idx;
 549
 550         ddr_perf_counter_enable(pmu, event->attr.config, counter, false);
 551         ddr_perf_event_update(event);
 552
 553         hwc->state |= PERF_HES_STOPPED;
 554 }
 555
 556 static void ddr_perf_event_del(struct perf_event *event, int flags)
 557 {
 558         struct ddr_pmu *pmu = to_ddr_pmu(event->pmu);
 559         struct hw_perf_event *hwc = &event->hw;
 560         int counter = hwc->idx;
 561
 562         ddr_perf_event_stop(event, PERF_EF_UPDATE);
 563
 564         ddr_perf_free_counter(pmu, counter);
 565         pmu->active_events--;
 566         hwc->idx = -1;
 567 }
 568
 569 static void ddr_perf_pmu_enable(struct pmu *pmu)
 570 {
 571         struct ddr_pmu *ddr_pmu = to_ddr_pmu(pmu);
 572
 573         /* enable cycle counter if cycle is not active event list */
 574         if (ddr_pmu->events[EVENT_CYCLES_COUNTER] == NULL)
 575                 ddr_perf_counter_enable(ddr_pmu,
 576                                       EVENT_CYCLES_ID,
 577                                       EVENT_CYCLES_COUNTER,
 578                                       true);
 579 }
 580
 581 static void ddr_perf_pmu_disable(struct pmu *pmu)
 582 {
 583         struct ddr_pmu *ddr_pmu = to_ddr_pmu(pmu);
 584
 585         if (ddr_pmu->events[EVENT_CYCLES_COUNTER] == NULL)
 586                 ddr_perf_counter_enable(ddr_pmu,
 587                                       EVENT_CYCLES_ID,
 588                                       EVENT_CYCLES_COUNTER,
 589                                       false);
 590 }
 591
 592 static int ddr_perf_init(struct ddr_pmu *pmu, void __iomem *base,
 593                          struct device *dev)
 594 {
 595         *pmu = (struct ddr_pmu) {
 596                 .pmu = (struct pmu) {
 597                         .module       = THIS_MODULE,
 598                         .capabilities = PERF_PMU_CAP_NO_EXCLUDE,
 599                         .task_ctx_nr = perf_invalid_context,
 600                         .attr_groups = attr_groups,
 601                         .event_init  = ddr_perf_event_init,
 602                         .add         = ddr_perf_event_add,
 603                         .del         = ddr_perf_event_del,
 604                         .start       = ddr_perf_event_start,
 605                         .stop        = ddr_perf_event_stop,
 606                         .read        = ddr_perf_event_update,
 607                         .pmu_enable  = ddr_perf_pmu_enable,
 608                         .pmu_disable = ddr_perf_pmu_disable,
 609                 },
 610                 .base = base,
 611                 .dev = dev,
 612         };
 613
 614         pmu->id = ida_simple_get(&ddr_ida, 0, 0, GFP_KERNEL);
 615         return pmu->id;
 616 }
 617
 618 static irqreturn_t ddr_perf_irq_handler(int irq, void *p)
 619 {
 620         int i;
 621         struct ddr_pmu *pmu = (struct ddr_pmu *) p;
 622         struct perf_event *event;
 623
 624         /* all counter will stop if cycle counter disabled */
 625         ddr_perf_counter_enable(pmu,
 626                               EVENT_CYCLES_ID,
 627                               EVENT_CYCLES_COUNTER,
 628                               false);
 629         /*
 630          * When the cycle counter overflows, all counters are stopped,
 631          * and an IRQ is raised. If any other counter overflows, it
 632          * continues counting, and no IRQ is raised. But for new SoCs,
 633          * such as i.MX8MP, event counter would stop when overflow, so
 634          * we need use cycle counter to stop overflow of event counter.
 635          *
 636          * Cycles occur at least 4 times as often as other events, so we
 637          * can update all events on a cycle counter overflow and not
 638          * lose events.
 639          *
 640          */
 641         for (i = 0; i < NUM_COUNTERS; i++) {
 642
 643                 if (!pmu->events[i])
 644                         continue;
 645
 646                 event = pmu->events[i];
 647
 648                 ddr_perf_event_update(event);
 649         }
 650
 651         ddr_perf_counter_enable(pmu,
 652                               EVENT_CYCLES_ID,
 653                               EVENT_CYCLES_COUNTER,
 654                               true);
 655
 656         return IRQ_HANDLED;
 657 }
 658
 659 static int ddr_perf_offline_cpu(unsigned int cpu, struct hlist_node *node)
 660 {
 661         struct ddr_pmu *pmu = hlist_entry_safe(node, struct ddr_pmu, node);
 662         int target;
 663
 664         if (cpu != pmu->cpu)
 665                 return 0;
 666
 667         target = cpumask_any_but(cpu_online_mask, cpu);
 668         if (target >= nr_cpu_ids)
 669                 return 0;
 670
 671         perf_pmu_migrate_context(&pmu->pmu, cpu, target);
 672         pmu->cpu = target;
 673
 674         WARN_ON(irq_set_affinity(pmu->irq, cpumask_of(pmu->cpu)));
 675
 676         return 0;
 677 }
 678
 679 static int ddr_perf_probe(struct platform_device *pdev)
 680 {
 681         struct ddr_pmu *pmu;
 682         struct device_node *np;
 683         void __iomem *base;
 684         char *name;
 685         int num;
 686         int ret;
 687         int irq;
 688
 689         base = devm_platform_ioremap_resource(pdev, 0);
 690         if (IS_ERR(base))
 691                 return PTR_ERR(base);
 692
 693         np = pdev->dev.of_node;
 694
 695         pmu = devm_kzalloc(&pdev->dev, sizeof(*pmu), GFP_KERNEL);
 696         if (!pmu)
 697                 return -ENOMEM;
 698
 699         num = ddr_perf_init(pmu, base, &pdev->dev);
 700
 701         platform_set_drvdata(pdev, pmu);
 702
 703         name = devm_kasprintf(&pdev->dev, GFP_KERNEL, DDR_PERF_DEV_NAME "%d",
 704                               num);
 705         if (!name) {
 706                 ret = -ENOMEM;
 707                 goto cpuhp_state_err;
 708         }
 709
 710         pmu->devtype_data = of_device_get_match_data(&pdev->dev);
 711
 712         pmu->cpu = raw_smp_processor_id();
 713         ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN,
 714                                       DDR_CPUHP_CB_NAME,
 715                                       NULL,
 716                                       ddr_perf_offline_cpu);
 717
 718         if (ret < 0) {
 719                 dev_err(&pdev->dev, "cpuhp_setup_state_multi failed\n");
 720                 goto cpuhp_state_err;
 721         }
 722
 723         pmu->cpuhp_state = ret;
 724
 725         /* Register the pmu instance for cpu hotplug */
 726         ret = cpuhp_state_add_instance_nocalls(pmu->cpuhp_state, &pmu->node);
 727         if (ret) {
 728                 dev_err(&pdev->dev, "Error %d registering hotplug\n", ret);
 729                 goto cpuhp_instance_err;
 730         }
 731
 732         /* Request irq */
 733         irq = of_irq_get(np, 0);
 734         if (irq < 0) {
 735                 dev_err(&pdev->dev, "Failed to get irq: %d", irq);
 736                 ret = irq;
 737                 goto ddr_perf_err;
 738         }
 739
 740         ret = devm_request_irq(&pdev->dev, irq,
 741                                         ddr_perf_irq_handler,
 742                                         IRQF_NOBALANCING | IRQF_NO_THREAD,
 743                                         DDR_CPUHP_CB_NAME,
 744                                         pmu);
 745         if (ret < 0) {
 746                 dev_err(&pdev->dev, "Request irq failed: %d", ret);
 747                 goto ddr_perf_err;
 748         }
 749
 750         pmu->irq = irq;
 751         ret = irq_set_affinity(pmu->irq, cpumask_of(pmu->cpu));
 752         if (ret) {
 753                 dev_err(pmu->dev, "Failed to set interrupt affinity!\n");
 754                 goto ddr_perf_err;
 755         }
 756
 757         ret = perf_pmu_register(&pmu->pmu, name, -1);
 758         if (ret)
 759                 goto ddr_perf_err;
 760
 761         return 0;
 762
 763 ddr_perf_err:
 764         cpuhp_state_remove_instance_nocalls(pmu->cpuhp_state, &pmu->node);
 765 cpuhp_instance_err:
 766         cpuhp_remove_multi_state(pmu->cpuhp_state);
 767 cpuhp_state_err:
 768         ida_simple_remove(&ddr_ida, pmu->id);
 769         dev_warn(&pdev->dev, "i.MX8 DDR Perf PMU failed (%d), disabled\n", ret);
 770         return ret;
 771 }
 772
 773 static int ddr_perf_remove(struct platform_device *pdev)
 774 {
 775         struct ddr_pmu *pmu = platform_get_drvdata(pdev);
 776
 777         cpuhp_state_remove_instance_nocalls(pmu->cpuhp_state, &pmu->node);
 778         cpuhp_remove_multi_state(pmu->cpuhp_state);
 779
 780         perf_pmu_unregister(&pmu->pmu);
 781
 782         ida_simple_remove(&ddr_ida, pmu->id);
 783         return 0;
 784 }
 785
 786 static struct platform_driver imx_ddr_pmu_driver = {
 787         .driver         = {
 788                 .name   = "imx-ddr-pmu",
 789                 .of_match_table = imx_ddr_pmu_dt_ids,
 790                 .suppress_bind_attrs = true,
 791         },
 792         .probe          = ddr_perf_probe,
 793         .remove         = ddr_perf_remove,
 794 };
 795
 796 module_platform_driver(imx_ddr_pmu_driver);
 797 MODULE_LICENSE("GPL v2");