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   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * ARM CoreSight Architecture PMU driver.
   4 *
   5 * This driver adds support for uncore PMU based on ARM CoreSight Performance
   6 * Monitoring Unit Architecture. The PMU is accessible via MMIO registers and
   7 * like other uncore PMUs, it does not support process specific events and
   8 * cannot be used in sampling mode.
   9 *
  10 * This code is based on other uncore PMUs like ARM DSU PMU. It provides a
  11 * generic implementation to operate the PMU according to CoreSight PMU
  12 * architecture and ACPI ARM PMU table (APMT) documents below:
  13 *   - ARM CoreSight PMU architecture document number: ARM IHI 0091 A.a-00bet0.
  14 *   - APMT document number: ARM DEN0117.
  15 *
  16 * The user should refer to the vendor technical documentation to get details
  17 * about the supported events.
  18 *
  19 * Copyright (c) 2022, NVIDIA CORPORATION & AFFILIATES. All rights reserved.
  20 *
  21 */
  22
  23#include <linux/acpi.h>
  24#include <linux/cacheinfo.h>
  25#include <linux/ctype.h>
  26#include <linux/interrupt.h>
  27#include <linux/io-64-nonatomic-lo-hi.h>
  28#include <linux/module.h>
  29#include <linux/perf_event.h>
  30#include <linux/platform_device.h>
  31#include <acpi/processor.h>
  32
  33#include "arm_cspmu.h"
  34#include "nvidia_cspmu.h"
  35
  36#define PMUNAME "arm_cspmu"
  37#define DRVNAME "arm-cs-arch-pmu"
  38
  39#define ARM_CSPMU_CPUMASK_ATTR(_name, _config)			\
  40	ARM_CSPMU_EXT_ATTR(_name, arm_cspmu_cpumask_show,	\
  41				(unsigned long)_config)
  42
  43/*
  44 * CoreSight PMU Arch register offsets.
  45 */
  46#define PMEVCNTR_LO					0x0
  47#define PMEVCNTR_HI					0x4
  48#define PMEVTYPER					0x400
  49#define PMCCFILTR					0x47C
  50#define PMEVFILTR					0xA00
  51#define PMCNTENSET					0xC00
  52#define PMCNTENCLR					0xC20
  53#define PMINTENSET					0xC40
  54#define PMINTENCLR					0xC60
  55#define PMOVSCLR					0xC80
  56#define PMOVSSET					0xCC0
  57#define PMCFGR						0xE00
  58#define PMCR						0xE04
  59#define PMIIDR						0xE08
  60
  61/* PMCFGR register field */
  62#define PMCFGR_NCG					GENMASK(31, 28)
  63#define PMCFGR_HDBG					BIT(24)
  64#define PMCFGR_TRO					BIT(23)
  65#define PMCFGR_SS					BIT(22)
  66#define PMCFGR_FZO					BIT(21)
  67#define PMCFGR_MSI					BIT(20)
  68#define PMCFGR_UEN					BIT(19)
  69#define PMCFGR_NA					BIT(17)
  70#define PMCFGR_EX					BIT(16)
  71#define PMCFGR_CCD					BIT(15)
  72#define PMCFGR_CC					BIT(14)
  73#define PMCFGR_SIZE					GENMASK(13, 8)
  74#define PMCFGR_N					GENMASK(7, 0)
  75
  76/* PMCR register field */
  77#define PMCR_TRO					BIT(11)
  78#define PMCR_HDBG					BIT(10)
  79#define PMCR_FZO					BIT(9)
  80#define PMCR_NA						BIT(8)
  81#define PMCR_DP						BIT(5)
  82#define PMCR_X						BIT(4)
  83#define PMCR_D						BIT(3)
  84#define PMCR_C						BIT(2)
  85#define PMCR_P						BIT(1)
  86#define PMCR_E						BIT(0)
  87
  88/* Each SET/CLR register supports up to 32 counters. */
  89#define ARM_CSPMU_SET_CLR_COUNTER_SHIFT		5
  90#define ARM_CSPMU_SET_CLR_COUNTER_NUM		\
  91	(1 << ARM_CSPMU_SET_CLR_COUNTER_SHIFT)
  92
  93/* Convert counter idx into SET/CLR register number. */
  94#define COUNTER_TO_SET_CLR_ID(idx)			\
  95	(idx >> ARM_CSPMU_SET_CLR_COUNTER_SHIFT)
  96
  97/* Convert counter idx into SET/CLR register bit. */
  98#define COUNTER_TO_SET_CLR_BIT(idx)			\
  99	(idx & (ARM_CSPMU_SET_CLR_COUNTER_NUM - 1))
 100
 101#define ARM_CSPMU_ACTIVE_CPU_MASK		0x0
 102#define ARM_CSPMU_ASSOCIATED_CPU_MASK		0x1
 103
 104/* Check if field f in flags is set with value v */
 105#define CHECK_APMT_FLAG(flags, f, v) \
 106	((flags & (ACPI_APMT_FLAGS_ ## f)) == (ACPI_APMT_FLAGS_ ## f ## _ ## v))
 107
 108/* Check and use default if implementer doesn't provide attribute callback */
 109#define CHECK_DEFAULT_IMPL_OPS(ops, callback)			\
 110	do {							\
 111		if (!ops->callback)				\
 112			ops->callback = arm_cspmu_ ## callback;	\
 113	} while (0)
 114
 115/*
 116 * Maximum poll count for reading counter value using high-low-high sequence.
 117 */
 118#define HILOHI_MAX_POLL	1000
 119
 120/* JEDEC-assigned JEP106 identification code */
 121#define ARM_CSPMU_IMPL_ID_NVIDIA		0x36B
 122
 123static unsigned long arm_cspmu_cpuhp_state;
 124
 125/*
 126 * In CoreSight PMU architecture, all of the MMIO registers are 32-bit except
 127 * counter register. The counter register can be implemented as 32-bit or 64-bit
 128 * register depending on the value of PMCFGR.SIZE field. For 64-bit access,
 129 * single-copy 64-bit atomic support is implementation defined. APMT node flag
 130 * is used to identify if the PMU supports 64-bit single copy atomic. If 64-bit
 131 * single copy atomic is not supported, the driver treats the register as a pair
 132 * of 32-bit register.
 133 */
 134
 135/*
 136 * Read 64-bit register as a pair of 32-bit registers using hi-lo-hi sequence.
 137 */
 138static u64 read_reg64_hilohi(const void __iomem *addr, u32 max_poll_count)
 139{
 140	u32 val_lo, val_hi;
 141	u64 val;
 142
 143	/* Use high-low-high sequence to avoid tearing */
 144	do {
 145		if (max_poll_count-- == 0) {
 146			pr_err("ARM CSPMU: timeout hi-low-high sequence\n");
 147			return 0;
 148		}
 149
 150		val_hi = readl(addr + 4);
 151		val_lo = readl(addr);
 152	} while (val_hi != readl(addr + 4));
 153
 154	val = (((u64)val_hi << 32) | val_lo);
 155
 156	return val;
 157}
 158
 159/* Check if PMU supports 64-bit single copy atomic. */
 160static inline bool supports_64bit_atomics(const struct arm_cspmu *cspmu)
 161{
 162	return CHECK_APMT_FLAG(cspmu->apmt_node->flags, ATOMIC, SUPP);
 163}
 164
 165/* Check if cycle counter is supported. */
 166static inline bool supports_cycle_counter(const struct arm_cspmu *cspmu)
 167{
 168	return (cspmu->pmcfgr & PMCFGR_CC);
 169}
 170
 171/* Get counter size, which is (PMCFGR_SIZE + 1). */
 172static inline u32 counter_size(const struct arm_cspmu *cspmu)
 173{
 174	return FIELD_GET(PMCFGR_SIZE, cspmu->pmcfgr) + 1;
 175}
 176
 177/* Get counter mask. */
 178static inline u64 counter_mask(const struct arm_cspmu *cspmu)
 179{
 180	return GENMASK_ULL(counter_size(cspmu) - 1, 0);
 181}
 182
 183/* Check if counter is implemented as 64-bit register. */
 184static inline bool use_64b_counter_reg(const struct arm_cspmu *cspmu)
 185{
 186	return (counter_size(cspmu) > 32);
 187}
 188
 189ssize_t arm_cspmu_sysfs_event_show(struct device *dev,
 190				struct device_attribute *attr, char *buf)
 191{
 192	struct dev_ext_attribute *eattr =
 193		container_of(attr, struct dev_ext_attribute, attr);
 194	return sysfs_emit(buf, "event=0x%llx\n",
 195			  (unsigned long long)eattr->var);
 196}
 197EXPORT_SYMBOL_GPL(arm_cspmu_sysfs_event_show);
 198
 199/* Default event list. */
 200static struct attribute *arm_cspmu_event_attrs[] = {
 201	ARM_CSPMU_EVENT_ATTR(cycles, ARM_CSPMU_EVT_CYCLES_DEFAULT),
 202	NULL,
 203};
 204
 205static struct attribute **
 206arm_cspmu_get_event_attrs(const struct arm_cspmu *cspmu)
 207{
 208	struct attribute **attrs;
 209
 210	attrs = devm_kmemdup(cspmu->dev, arm_cspmu_event_attrs,
 211		sizeof(arm_cspmu_event_attrs), GFP_KERNEL);
 212
 213	return attrs;
 214}
 215
 216static umode_t
 217arm_cspmu_event_attr_is_visible(struct kobject *kobj,
 218				struct attribute *attr, int unused)
 219{
 220	struct device *dev = kobj_to_dev(kobj);
 221	struct arm_cspmu *cspmu = to_arm_cspmu(dev_get_drvdata(dev));
 222	struct perf_pmu_events_attr *eattr;
 223
 224	eattr = container_of(attr, typeof(*eattr), attr.attr);
 225
 226	/* Hide cycle event if not supported */
 227	if (!supports_cycle_counter(cspmu) &&
 228	    eattr->id == ARM_CSPMU_EVT_CYCLES_DEFAULT)
 229		return 0;
 230
 231	return attr->mode;
 232}
 233
 234ssize_t arm_cspmu_sysfs_format_show(struct device *dev,
 235				struct device_attribute *attr,
 236				char *buf)
 237{
 238	struct dev_ext_attribute *eattr =
 239		container_of(attr, struct dev_ext_attribute, attr);
 240	return sysfs_emit(buf, "%s\n", (char *)eattr->var);
 241}
 242EXPORT_SYMBOL_GPL(arm_cspmu_sysfs_format_show);
 243
 244static struct attribute *arm_cspmu_format_attrs[] = {
 245	ARM_CSPMU_FORMAT_EVENT_ATTR,
 246	ARM_CSPMU_FORMAT_FILTER_ATTR,
 247	NULL,
 248};
 249
 250static struct attribute **
 251arm_cspmu_get_format_attrs(const struct arm_cspmu *cspmu)
 252{
 253	struct attribute **attrs;
 254
 255	attrs = devm_kmemdup(cspmu->dev, arm_cspmu_format_attrs,
 256		sizeof(arm_cspmu_format_attrs), GFP_KERNEL);
 257
 258	return attrs;
 259}
 260
 261static u32 arm_cspmu_event_type(const struct perf_event *event)
 262{
 263	return event->attr.config & ARM_CSPMU_EVENT_MASK;
 264}
 265
 266static bool arm_cspmu_is_cycle_counter_event(const struct perf_event *event)
 267{
 268	return (event->attr.config == ARM_CSPMU_EVT_CYCLES_DEFAULT);
 269}
 270
 271static u32 arm_cspmu_event_filter(const struct perf_event *event)
 272{
 273	return event->attr.config1 & ARM_CSPMU_FILTER_MASK;
 274}
 275
 276static ssize_t arm_cspmu_identifier_show(struct device *dev,
 277					 struct device_attribute *attr,
 278					 char *page)
 279{
 280	struct arm_cspmu *cspmu = to_arm_cspmu(dev_get_drvdata(dev));
 281
 282	return sysfs_emit(page, "%s\n", cspmu->identifier);
 283}
 284
 285static struct device_attribute arm_cspmu_identifier_attr =
 286	__ATTR(identifier, 0444, arm_cspmu_identifier_show, NULL);
 287
 288static struct attribute *arm_cspmu_identifier_attrs[] = {
 289	&arm_cspmu_identifier_attr.attr,
 290	NULL,
 291};
 292
 293static struct attribute_group arm_cspmu_identifier_attr_group = {
 294	.attrs = arm_cspmu_identifier_attrs,
 295};
 296
 297static const char *arm_cspmu_get_identifier(const struct arm_cspmu *cspmu)
 298{
 299	const char *identifier =
 300		devm_kasprintf(cspmu->dev, GFP_KERNEL, "%x",
 301			       cspmu->impl.pmiidr);
 302	return identifier;
 303}
 304
 305static const char *arm_cspmu_type_str[ACPI_APMT_NODE_TYPE_COUNT] = {
 306	"mc",
 307	"smmu",
 308	"pcie",
 309	"acpi",
 310	"cache",
 311};
 312
 313static const char *arm_cspmu_get_name(const struct arm_cspmu *cspmu)
 314{
 315	struct device *dev;
 316	struct acpi_apmt_node *apmt_node;
 317	u8 pmu_type;
 318	char *name;
 319	char acpi_hid_string[ACPI_ID_LEN] = { 0 };
 320	static atomic_t pmu_idx[ACPI_APMT_NODE_TYPE_COUNT] = { 0 };
 321
 322	dev = cspmu->dev;
 323	apmt_node = cspmu->apmt_node;
 324	pmu_type = apmt_node->type;
 325
 326	if (pmu_type >= ACPI_APMT_NODE_TYPE_COUNT) {
 327		dev_err(dev, "unsupported PMU type-%u\n", pmu_type);
 328		return NULL;
 329	}
 330
 331	if (pmu_type == ACPI_APMT_NODE_TYPE_ACPI) {
 332		memcpy(acpi_hid_string,
 333			&apmt_node->inst_primary,
 334			sizeof(apmt_node->inst_primary));
 335		name = devm_kasprintf(dev, GFP_KERNEL, "%s_%s_%s_%u", PMUNAME,
 336				      arm_cspmu_type_str[pmu_type],
 337				      acpi_hid_string,
 338				      apmt_node->inst_secondary);
 339	} else {
 340		name = devm_kasprintf(dev, GFP_KERNEL, "%s_%s_%d", PMUNAME,
 341				      arm_cspmu_type_str[pmu_type],
 342				      atomic_fetch_inc(&pmu_idx[pmu_type]));
 343	}
 344
 345	return name;
 346}
 347
 348static ssize_t arm_cspmu_cpumask_show(struct device *dev,
 349				      struct device_attribute *attr,
 350				      char *buf)
 351{
 352	struct pmu *pmu = dev_get_drvdata(dev);
 353	struct arm_cspmu *cspmu = to_arm_cspmu(pmu);
 354	struct dev_ext_attribute *eattr =
 355		container_of(attr, struct dev_ext_attribute, attr);
 356	unsigned long mask_id = (unsigned long)eattr->var;
 357	const cpumask_t *cpumask;
 358
 359	switch (mask_id) {
 360	case ARM_CSPMU_ACTIVE_CPU_MASK:
 361		cpumask = &cspmu->active_cpu;
 362		break;
 363	case ARM_CSPMU_ASSOCIATED_CPU_MASK:
 364		cpumask = &cspmu->associated_cpus;
 365		break;
 366	default:
 367		return 0;
 368	}
 369	return cpumap_print_to_pagebuf(true, buf, cpumask);
 370}
 371
 372static struct attribute *arm_cspmu_cpumask_attrs[] = {
 373	ARM_CSPMU_CPUMASK_ATTR(cpumask, ARM_CSPMU_ACTIVE_CPU_MASK),
 374	ARM_CSPMU_CPUMASK_ATTR(associated_cpus, ARM_CSPMU_ASSOCIATED_CPU_MASK),
 375	NULL,
 376};
 377
 378static struct attribute_group arm_cspmu_cpumask_attr_group = {
 379	.attrs = arm_cspmu_cpumask_attrs,
 380};
 381
 382struct impl_match {
 383	u32 pmiidr;
 384	u32 mask;
 385	int (*impl_init_ops)(struct arm_cspmu *cspmu);
 386};
 387
 388static const struct impl_match impl_match[] = {
 389	{
 390	  .pmiidr = ARM_CSPMU_IMPL_ID_NVIDIA,
 391	  .mask = ARM_CSPMU_PMIIDR_IMPLEMENTER,
 392	  .impl_init_ops = nv_cspmu_init_ops
 393	},
 394	{}
 395};
 396
 397static int arm_cspmu_init_impl_ops(struct arm_cspmu *cspmu)
 398{
 399	int ret;
 400	struct acpi_apmt_node *apmt_node = cspmu->apmt_node;
 401	struct arm_cspmu_impl_ops *impl_ops = &cspmu->impl.ops;
 402	const struct impl_match *match = impl_match;
 403
 404	/*
 405	 * Get PMU implementer and product id from APMT node.
 406	 * If APMT node doesn't have implementer/product id, try get it
 407	 * from PMIIDR.
 408	 */
 409	cspmu->impl.pmiidr =
 410		(apmt_node->impl_id) ? apmt_node->impl_id :
 411				       readl(cspmu->base0 + PMIIDR);
 412
 413	/* Find implementer specific attribute ops. */
 414	for (; match->pmiidr; match++) {
 415		const u32 mask = match->mask;
 416
 417		if ((match->pmiidr & mask) == (cspmu->impl.pmiidr & mask)) {
 418			ret = match->impl_init_ops(cspmu);
 419			if (ret)
 420				return ret;
 421
 422			break;
 423		}
 424	}
 425
 426	/* Use default callbacks if implementer doesn't provide one. */
 427	CHECK_DEFAULT_IMPL_OPS(impl_ops, get_event_attrs);
 428	CHECK_DEFAULT_IMPL_OPS(impl_ops, get_format_attrs);
 429	CHECK_DEFAULT_IMPL_OPS(impl_ops, get_identifier);
 430	CHECK_DEFAULT_IMPL_OPS(impl_ops, get_name);
 431	CHECK_DEFAULT_IMPL_OPS(impl_ops, is_cycle_counter_event);
 432	CHECK_DEFAULT_IMPL_OPS(impl_ops, event_type);
 433	CHECK_DEFAULT_IMPL_OPS(impl_ops, event_filter);
 434	CHECK_DEFAULT_IMPL_OPS(impl_ops, event_attr_is_visible);
 435
 436	return 0;
 437}
 438
 439static struct attribute_group *
 440arm_cspmu_alloc_event_attr_group(struct arm_cspmu *cspmu)
 441{
 442	struct attribute_group *event_group;
 443	struct device *dev = cspmu->dev;
 444	const struct arm_cspmu_impl_ops *impl_ops = &cspmu->impl.ops;
 445
 446	event_group =
 447		devm_kzalloc(dev, sizeof(struct attribute_group), GFP_KERNEL);
 448	if (!event_group)
 449		return NULL;
 450
 451	event_group->name = "events";
 452	event_group->is_visible = impl_ops->event_attr_is_visible;
 453	event_group->attrs = impl_ops->get_event_attrs(cspmu);
 454
 455	if (!event_group->attrs)
 456		return NULL;
 457
 458	return event_group;
 459}
 460
 461static struct attribute_group *
 462arm_cspmu_alloc_format_attr_group(struct arm_cspmu *cspmu)
 463{
 464	struct attribute_group *format_group;
 465	struct device *dev = cspmu->dev;
 466
 467	format_group =
 468		devm_kzalloc(dev, sizeof(struct attribute_group), GFP_KERNEL);
 469	if (!format_group)
 470		return NULL;
 471
 472	format_group->name = "format";
 473	format_group->attrs = cspmu->impl.ops.get_format_attrs(cspmu);
 474
 475	if (!format_group->attrs)
 476		return NULL;
 477
 478	return format_group;
 479}
 480
 481static struct attribute_group **
 482arm_cspmu_alloc_attr_group(struct arm_cspmu *cspmu)
 483{
 484	struct attribute_group **attr_groups = NULL;
 485	struct device *dev = cspmu->dev;
 486	const struct arm_cspmu_impl_ops *impl_ops = &cspmu->impl.ops;
 487	int ret;
 488
 489	ret = arm_cspmu_init_impl_ops(cspmu);
 490	if (ret)
 491		return NULL;
 492
 493	cspmu->identifier = impl_ops->get_identifier(cspmu);
 494	cspmu->name = impl_ops->get_name(cspmu);
 495
 496	if (!cspmu->identifier || !cspmu->name)
 497		return NULL;
 498
 499	attr_groups = devm_kcalloc(dev, 5, sizeof(struct attribute_group *),
 500				   GFP_KERNEL);
 501	if (!attr_groups)
 502		return NULL;
 503
 504	attr_groups[0] = arm_cspmu_alloc_event_attr_group(cspmu);
 505	attr_groups[1] = arm_cspmu_alloc_format_attr_group(cspmu);
 506	attr_groups[2] = &arm_cspmu_identifier_attr_group;
 507	attr_groups[3] = &arm_cspmu_cpumask_attr_group;
 508
 509	if (!attr_groups[0] || !attr_groups[1])
 510		return NULL;
 511
 512	return attr_groups;
 513}
 514
 515static inline void arm_cspmu_reset_counters(struct arm_cspmu *cspmu)
 516{
 517	u32 pmcr = 0;
 518
 519	pmcr |= PMCR_P;
 520	pmcr |= PMCR_C;
 521	writel(pmcr, cspmu->base0 + PMCR);
 522}
 523
 524static inline void arm_cspmu_start_counters(struct arm_cspmu *cspmu)
 525{
 526	writel(PMCR_E, cspmu->base0 + PMCR);
 527}
 528
 529static inline void arm_cspmu_stop_counters(struct arm_cspmu *cspmu)
 530{
 531	writel(0, cspmu->base0 + PMCR);
 532}
 533
 534static void arm_cspmu_enable(struct pmu *pmu)
 535{
 536	bool disabled;
 537	struct arm_cspmu *cspmu = to_arm_cspmu(pmu);
 538
 539	disabled = bitmap_empty(cspmu->hw_events.used_ctrs,
 540				cspmu->num_logical_ctrs);
 541
 542	if (disabled)
 543		return;
 544
 545	arm_cspmu_start_counters(cspmu);
 546}
 547
 548static void arm_cspmu_disable(struct pmu *pmu)
 549{
 550	struct arm_cspmu *cspmu = to_arm_cspmu(pmu);
 551
 552	arm_cspmu_stop_counters(cspmu);
 553}
 554
 555static int arm_cspmu_get_event_idx(struct arm_cspmu_hw_events *hw_events,
 556				struct perf_event *event)
 557{
 558	int idx;
 559	struct arm_cspmu *cspmu = to_arm_cspmu(event->pmu);
 560
 561	if (supports_cycle_counter(cspmu)) {
 562		if (cspmu->impl.ops.is_cycle_counter_event(event)) {
 563			/* Search for available cycle counter. */
 564			if (test_and_set_bit(cspmu->cycle_counter_logical_idx,
 565					     hw_events->used_ctrs))
 566				return -EAGAIN;
 567
 568			return cspmu->cycle_counter_logical_idx;
 569		}
 570
 571		/*
 572		 * Search a regular counter from the used counter bitmap.
 573		 * The cycle counter divides the bitmap into two parts. Search
 574		 * the first then second half to exclude the cycle counter bit.
 575		 */
 576		idx = find_first_zero_bit(hw_events->used_ctrs,
 577					  cspmu->cycle_counter_logical_idx);
 578		if (idx >= cspmu->cycle_counter_logical_idx) {
 579			idx = find_next_zero_bit(
 580				hw_events->used_ctrs,
 581				cspmu->num_logical_ctrs,
 582				cspmu->cycle_counter_logical_idx + 1);
 583		}
 584	} else {
 585		idx = find_first_zero_bit(hw_events->used_ctrs,
 586					  cspmu->num_logical_ctrs);
 587	}
 588
 589	if (idx >= cspmu->num_logical_ctrs)
 590		return -EAGAIN;
 591
 592	set_bit(idx, hw_events->used_ctrs);
 593
 594	return idx;
 595}
 596
 597static bool arm_cspmu_validate_event(struct pmu *pmu,
 598				 struct arm_cspmu_hw_events *hw_events,
 599				 struct perf_event *event)
 600{
 601	if (is_software_event(event))
 602		return true;
 603
 604	/* Reject groups spanning multiple HW PMUs. */
 605	if (event->pmu != pmu)
 606		return false;
 607
 608	return (arm_cspmu_get_event_idx(hw_events, event) >= 0);
 609}
 610
 611/*
 612 * Make sure the group of events can be scheduled at once
 613 * on the PMU.
 614 */
 615static bool arm_cspmu_validate_group(struct perf_event *event)
 616{
 617	struct perf_event *sibling, *leader = event->group_leader;
 618	struct arm_cspmu_hw_events fake_hw_events;
 619
 620	if (event->group_leader == event)
 621		return true;
 622
 623	memset(&fake_hw_events, 0, sizeof(fake_hw_events));
 624
 625	if (!arm_cspmu_validate_event(event->pmu, &fake_hw_events, leader))
 626		return false;
 627
 628	for_each_sibling_event(sibling, leader) {
 629		if (!arm_cspmu_validate_event(event->pmu, &fake_hw_events,
 630						  sibling))
 631			return false;
 632	}
 633
 634	return arm_cspmu_validate_event(event->pmu, &fake_hw_events, event);
 635}
 636
 637static int arm_cspmu_event_init(struct perf_event *event)
 638{
 639	struct arm_cspmu *cspmu;
 640	struct hw_perf_event *hwc = &event->hw;
 641
 642	cspmu = to_arm_cspmu(event->pmu);
 643
 644	/*
 645	 * Following other "uncore" PMUs, we do not support sampling mode or
 646	 * attach to a task (per-process mode).
 647	 */
 648	if (is_sampling_event(event)) {
 649		dev_dbg(cspmu->pmu.dev,
 650			"Can't support sampling events\n");
 651		return -EOPNOTSUPP;
 652	}
 653
 654	if (event->cpu < 0 || event->attach_state & PERF_ATTACH_TASK) {
 655		dev_dbg(cspmu->pmu.dev,
 656			"Can't support per-task counters\n");
 657		return -EINVAL;
 658	}
 659
 660	/*
 661	 * Make sure the CPU assignment is on one of the CPUs associated with
 662	 * this PMU.
 663	 */
 664	if (!cpumask_test_cpu(event->cpu, &cspmu->associated_cpus)) {
 665		dev_dbg(cspmu->pmu.dev,
 666			"Requested cpu is not associated with the PMU\n");
 667		return -EINVAL;
 668	}
 669
 670	/* Enforce the current active CPU to handle the events in this PMU. */
 671	event->cpu = cpumask_first(&cspmu->active_cpu);
 672	if (event->cpu >= nr_cpu_ids)
 673		return -EINVAL;
 674
 675	if (!arm_cspmu_validate_group(event))
 676		return -EINVAL;
 677
 678	/*
 679	 * The logical counter id is tracked with hw_perf_event.extra_reg.idx.
 680	 * The physical counter id is tracked with hw_perf_event.idx.
 681	 * We don't assign an index until we actually place the event onto
 682	 * hardware. Use -1 to signify that we haven't decided where to put it
 683	 * yet.
 684	 */
 685	hwc->idx = -1;
 686	hwc->extra_reg.idx = -1;
 687	hwc->config = cspmu->impl.ops.event_type(event);
 688
 689	return 0;
 690}
 691
 692static inline u32 counter_offset(u32 reg_sz, u32 ctr_idx)
 693{
 694	return (PMEVCNTR_LO + (reg_sz * ctr_idx));
 695}
 696
 697static void arm_cspmu_write_counter(struct perf_event *event, u64 val)
 698{
 699	u32 offset;
 700	struct arm_cspmu *cspmu = to_arm_cspmu(event->pmu);
 701
 702	if (use_64b_counter_reg(cspmu)) {
 703		offset = counter_offset(sizeof(u64), event->hw.idx);
 704
 705		writeq(val, cspmu->base1 + offset);
 706	} else {
 707		offset = counter_offset(sizeof(u32), event->hw.idx);
 708
 709		writel(lower_32_bits(val), cspmu->base1 + offset);
 710	}
 711}
 712
 713static u64 arm_cspmu_read_counter(struct perf_event *event)
 714{
 715	u32 offset;
 716	const void __iomem *counter_addr;
 717	struct arm_cspmu *cspmu = to_arm_cspmu(event->pmu);
 718
 719	if (use_64b_counter_reg(cspmu)) {
 720		offset = counter_offset(sizeof(u64), event->hw.idx);
 721		counter_addr = cspmu->base1 + offset;
 722
 723		return supports_64bit_atomics(cspmu) ?
 724			       readq(counter_addr) :
 725			       read_reg64_hilohi(counter_addr, HILOHI_MAX_POLL);
 726	}
 727
 728	offset = counter_offset(sizeof(u32), event->hw.idx);
 729	return readl(cspmu->base1 + offset);
 730}
 731
 732/*
 733 * arm_cspmu_set_event_period: Set the period for the counter.
 734 *
 735 * To handle cases of extreme interrupt latency, we program
 736 * the counter with half of the max count for the counters.
 737 */
 738static void arm_cspmu_set_event_period(struct perf_event *event)
 739{
 740	struct arm_cspmu *cspmu = to_arm_cspmu(event->pmu);
 741	u64 val = counter_mask(cspmu) >> 1ULL;
 742
 743	local64_set(&event->hw.prev_count, val);
 744	arm_cspmu_write_counter(event, val);
 745}
 746
 747static void arm_cspmu_enable_counter(struct arm_cspmu *cspmu, int idx)
 748{
 749	u32 reg_id, reg_bit, inten_off, cnten_off;
 750
 751	reg_id = COUNTER_TO_SET_CLR_ID(idx);
 752	reg_bit = COUNTER_TO_SET_CLR_BIT(idx);
 753
 754	inten_off = PMINTENSET + (4 * reg_id);
 755	cnten_off = PMCNTENSET + (4 * reg_id);
 756
 757	writel(BIT(reg_bit), cspmu->base0 + inten_off);
 758	writel(BIT(reg_bit), cspmu->base0 + cnten_off);
 759}
 760
 761static void arm_cspmu_disable_counter(struct arm_cspmu *cspmu, int idx)
 762{
 763	u32 reg_id, reg_bit, inten_off, cnten_off;
 764
 765	reg_id = COUNTER_TO_SET_CLR_ID(idx);
 766	reg_bit = COUNTER_TO_SET_CLR_BIT(idx);
 767
 768	inten_off = PMINTENCLR + (4 * reg_id);
 769	cnten_off = PMCNTENCLR + (4 * reg_id);
 770
 771	writel(BIT(reg_bit), cspmu->base0 + cnten_off);
 772	writel(BIT(reg_bit), cspmu->base0 + inten_off);
 773}
 774
 775static void arm_cspmu_event_update(struct perf_event *event)
 776{
 777	struct arm_cspmu *cspmu = to_arm_cspmu(event->pmu);
 778	struct hw_perf_event *hwc = &event->hw;
 779	u64 delta, prev, now;
 780
 781	do {
 782		prev = local64_read(&hwc->prev_count);
 783		now = arm_cspmu_read_counter(event);
 784	} while (local64_cmpxchg(&hwc->prev_count, prev, now) != prev);
 785
 786	delta = (now - prev) & counter_mask(cspmu);
 787	local64_add(delta, &event->count);
 788}
 789
 790static inline void arm_cspmu_set_event(struct arm_cspmu *cspmu,
 791					struct hw_perf_event *hwc)
 792{
 793	u32 offset = PMEVTYPER + (4 * hwc->idx);
 794
 795	writel(hwc->config, cspmu->base0 + offset);
 796}
 797
 798static inline void arm_cspmu_set_ev_filter(struct arm_cspmu *cspmu,
 799					   struct hw_perf_event *hwc,
 800					   u32 filter)
 801{
 802	u32 offset = PMEVFILTR + (4 * hwc->idx);
 803
 804	writel(filter, cspmu->base0 + offset);
 805}
 806
 807static inline void arm_cspmu_set_cc_filter(struct arm_cspmu *cspmu, u32 filter)
 808{
 809	u32 offset = PMCCFILTR;
 810
 811	writel(filter, cspmu->base0 + offset);
 812}
 813
 814static void arm_cspmu_start(struct perf_event *event, int pmu_flags)
 815{
 816	struct arm_cspmu *cspmu = to_arm_cspmu(event->pmu);
 817	struct hw_perf_event *hwc = &event->hw;
 818	u32 filter;
 819
 820	/* We always reprogram the counter */
 821	if (pmu_flags & PERF_EF_RELOAD)
 822		WARN_ON(!(hwc->state & PERF_HES_UPTODATE));
 823
 824	arm_cspmu_set_event_period(event);
 825
 826	filter = cspmu->impl.ops.event_filter(event);
 827
 828	if (event->hw.extra_reg.idx == cspmu->cycle_counter_logical_idx) {
 829		arm_cspmu_set_cc_filter(cspmu, filter);
 830	} else {
 831		arm_cspmu_set_event(cspmu, hwc);
 832		arm_cspmu_set_ev_filter(cspmu, hwc, filter);
 833	}
 834
 835	hwc->state = 0;
 836
 837	arm_cspmu_enable_counter(cspmu, hwc->idx);
 838}
 839
 840static void arm_cspmu_stop(struct perf_event *event, int pmu_flags)
 841{
 842	struct arm_cspmu *cspmu = to_arm_cspmu(event->pmu);
 843	struct hw_perf_event *hwc = &event->hw;
 844
 845	if (hwc->state & PERF_HES_STOPPED)
 846		return;
 847
 848	arm_cspmu_disable_counter(cspmu, hwc->idx);
 849	arm_cspmu_event_update(event);
 850
 851	hwc->state |= PERF_HES_STOPPED | PERF_HES_UPTODATE;
 852}
 853
 854static inline u32 to_phys_idx(struct arm_cspmu *cspmu, u32 idx)
 855{
 856	return (idx == cspmu->cycle_counter_logical_idx) ?
 857		ARM_CSPMU_CYCLE_CNTR_IDX : idx;
 858}
 859
 860static int arm_cspmu_add(struct perf_event *event, int flags)
 861{
 862	struct arm_cspmu *cspmu = to_arm_cspmu(event->pmu);
 863	struct arm_cspmu_hw_events *hw_events = &cspmu->hw_events;
 864	struct hw_perf_event *hwc = &event->hw;
 865	int idx;
 866
 867	if (WARN_ON_ONCE(!cpumask_test_cpu(smp_processor_id(),
 868					   &cspmu->associated_cpus)))
 869		return -ENOENT;
 870
 871	idx = arm_cspmu_get_event_idx(hw_events, event);
 872	if (idx < 0)
 873		return idx;
 874
 875	hw_events->events[idx] = event;
 876	hwc->idx = to_phys_idx(cspmu, idx);
 877	hwc->extra_reg.idx = idx;
 878	hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
 879
 880	if (flags & PERF_EF_START)
 881		arm_cspmu_start(event, PERF_EF_RELOAD);
 882
 883	/* Propagate changes to the userspace mapping. */
 884	perf_event_update_userpage(event);
 885
 886	return 0;
 887}
 888
 889static void arm_cspmu_del(struct perf_event *event, int flags)
 890{
 891	struct arm_cspmu *cspmu = to_arm_cspmu(event->pmu);
 892	struct arm_cspmu_hw_events *hw_events = &cspmu->hw_events;
 893	struct hw_perf_event *hwc = &event->hw;
 894	int idx = hwc->extra_reg.idx;
 895
 896	arm_cspmu_stop(event, PERF_EF_UPDATE);
 897
 898	hw_events->events[idx] = NULL;
 899
 900	clear_bit(idx, hw_events->used_ctrs);
 901
 902	perf_event_update_userpage(event);
 903}
 904
 905static void arm_cspmu_read(struct perf_event *event)
 906{
 907	arm_cspmu_event_update(event);
 908}
 909
 910static struct arm_cspmu *arm_cspmu_alloc(struct platform_device *pdev)
 911{
 912	struct acpi_apmt_node *apmt_node;
 913	struct arm_cspmu *cspmu;
 914	struct device *dev;
 915
 916	dev = &pdev->dev;
 917	apmt_node = *(struct acpi_apmt_node **)dev_get_platdata(dev);
 918	if (!apmt_node) {
 919		dev_err(dev, "failed to get APMT node\n");
 920		return NULL;
 921	}
 922
 923	cspmu = devm_kzalloc(dev, sizeof(*cspmu), GFP_KERNEL);
 924	if (!cspmu)
 925		return NULL;
 926
 927	cspmu->dev = dev;
 928	cspmu->apmt_node = apmt_node;
 929
 930	platform_set_drvdata(pdev, cspmu);
 931
 932	return cspmu;
 933}
 934
 935static int arm_cspmu_init_mmio(struct arm_cspmu *cspmu)
 936{
 937	struct device *dev;
 938	struct platform_device *pdev;
 939	struct acpi_apmt_node *apmt_node;
 940
 941	dev = cspmu->dev;
 942	pdev = to_platform_device(dev);
 943	apmt_node = cspmu->apmt_node;
 944
 945	/* Base address for page 0. */
 946	cspmu->base0 = devm_platform_ioremap_resource(pdev, 0);
 947	if (IS_ERR(cspmu->base0)) {
 948		dev_err(dev, "ioremap failed for page-0 resource\n");
 949		return PTR_ERR(cspmu->base0);
 950	}
 951
 952	/* Base address for page 1 if supported. Otherwise point to page 0. */
 953	cspmu->base1 = cspmu->base0;
 954	if (CHECK_APMT_FLAG(apmt_node->flags, DUAL_PAGE, SUPP)) {
 955		cspmu->base1 = devm_platform_ioremap_resource(pdev, 1);
 956		if (IS_ERR(cspmu->base1)) {
 957			dev_err(dev, "ioremap failed for page-1 resource\n");
 958			return PTR_ERR(cspmu->base1);
 959		}
 960	}
 961
 962	cspmu->pmcfgr = readl(cspmu->base0 + PMCFGR);
 963
 964	cspmu->num_logical_ctrs = FIELD_GET(PMCFGR_N, cspmu->pmcfgr) + 1;
 965
 966	cspmu->cycle_counter_logical_idx = ARM_CSPMU_MAX_HW_CNTRS;
 967
 968	if (supports_cycle_counter(cspmu)) {
 969		/*
 970		 * The last logical counter is mapped to cycle counter if
 971		 * there is a gap between regular and cycle counter. Otherwise,
 972		 * logical and physical have 1-to-1 mapping.
 973		 */
 974		cspmu->cycle_counter_logical_idx =
 975			(cspmu->num_logical_ctrs <= ARM_CSPMU_CYCLE_CNTR_IDX) ?
 976				cspmu->num_logical_ctrs - 1 :
 977				ARM_CSPMU_CYCLE_CNTR_IDX;
 978	}
 979
 980	cspmu->num_set_clr_reg =
 981		DIV_ROUND_UP(cspmu->num_logical_ctrs,
 982				ARM_CSPMU_SET_CLR_COUNTER_NUM);
 983
 984	cspmu->hw_events.events =
 985		devm_kcalloc(dev, cspmu->num_logical_ctrs,
 986			     sizeof(*cspmu->hw_events.events), GFP_KERNEL);
 987
 988	if (!cspmu->hw_events.events)
 989		return -ENOMEM;
 990
 991	return 0;
 992}
 993
 994static inline int arm_cspmu_get_reset_overflow(struct arm_cspmu *cspmu,
 995					       u32 *pmovs)
 996{
 997	int i;
 998	u32 pmovclr_offset = PMOVSCLR;
 999	u32 has_overflowed = 0;
1000
1001	for (i = 0; i < cspmu->num_set_clr_reg; ++i) {
1002		pmovs[i] = readl(cspmu->base1 + pmovclr_offset);
1003		has_overflowed |= pmovs[i];
1004		writel(pmovs[i], cspmu->base1 + pmovclr_offset);
1005		pmovclr_offset += sizeof(u32);
1006	}
1007
1008	return has_overflowed != 0;
1009}
1010
1011static irqreturn_t arm_cspmu_handle_irq(int irq_num, void *dev)
1012{
1013	int idx, has_overflowed;
1014	struct perf_event *event;
1015	struct arm_cspmu *cspmu = dev;
1016	DECLARE_BITMAP(pmovs, ARM_CSPMU_MAX_HW_CNTRS);
1017	bool handled = false;
1018
1019	arm_cspmu_stop_counters(cspmu);
1020
1021	has_overflowed = arm_cspmu_get_reset_overflow(cspmu, (u32 *)pmovs);
1022	if (!has_overflowed)
1023		goto done;
1024
1025	for_each_set_bit(idx, cspmu->hw_events.used_ctrs,
1026			cspmu->num_logical_ctrs) {
1027		event = cspmu->hw_events.events[idx];
1028
1029		if (!event)
1030			continue;
1031
1032		if (!test_bit(event->hw.idx, pmovs))
1033			continue;
1034
1035		arm_cspmu_event_update(event);
1036		arm_cspmu_set_event_period(event);
1037
1038		handled = true;
1039	}
1040
1041done:
1042	arm_cspmu_start_counters(cspmu);
1043	return IRQ_RETVAL(handled);
1044}
1045
1046static int arm_cspmu_request_irq(struct arm_cspmu *cspmu)
1047{
1048	int irq, ret;
1049	struct device *dev;
1050	struct platform_device *pdev;
1051	struct acpi_apmt_node *apmt_node;
1052
1053	dev = cspmu->dev;
1054	pdev = to_platform_device(dev);
1055	apmt_node = cspmu->apmt_node;
1056
1057	/* Skip IRQ request if the PMU does not support overflow interrupt. */
1058	if (apmt_node->ovflw_irq == 0)
1059		return 0;
1060
1061	irq = platform_get_irq(pdev, 0);
1062	if (irq < 0)
1063		return irq;
1064
1065	ret = devm_request_irq(dev, irq, arm_cspmu_handle_irq,
1066			       IRQF_NOBALANCING | IRQF_NO_THREAD, dev_name(dev),
1067			       cspmu);
1068	if (ret) {
1069		dev_err(dev, "Could not request IRQ %d\n", irq);
1070		return ret;
1071	}
1072
1073	cspmu->irq = irq;
1074
1075	return 0;
1076}
1077
1078static inline int arm_cspmu_find_cpu_container(int cpu, u32 container_uid)
1079{
1080	u32 acpi_uid;
1081	struct device *cpu_dev = get_cpu_device(cpu);
1082	struct acpi_device *acpi_dev = ACPI_COMPANION(cpu_dev);
1083
1084	if (!cpu_dev)
1085		return -ENODEV;
1086
1087	while (acpi_dev) {
1088		if (!strcmp(acpi_device_hid(acpi_dev),
1089			    ACPI_PROCESSOR_CONTAINER_HID) &&
1090		    !kstrtouint(acpi_device_uid(acpi_dev), 0, &acpi_uid) &&
1091		    acpi_uid == container_uid)
1092			return 0;
1093
1094		acpi_dev = acpi_dev_parent(acpi_dev);
1095	}
1096
1097	return -ENODEV;
1098}
1099
1100static int arm_cspmu_get_cpus(struct arm_cspmu *cspmu)
1101{
1102	struct device *dev;
1103	struct acpi_apmt_node *apmt_node;
1104	int affinity_flag;
1105	int cpu;
1106
1107	dev = cspmu->pmu.dev;
1108	apmt_node = cspmu->apmt_node;
1109	affinity_flag = apmt_node->flags & ACPI_APMT_FLAGS_AFFINITY;
1110
1111	if (affinity_flag == ACPI_APMT_FLAGS_AFFINITY_PROC) {
1112		for_each_possible_cpu(cpu) {
1113			if (apmt_node->proc_affinity ==
1114			    get_acpi_id_for_cpu(cpu)) {
1115				cpumask_set_cpu(cpu, &cspmu->associated_cpus);
1116				break;
1117			}
1118		}
1119	} else {
1120		for_each_possible_cpu(cpu) {
1121			if (arm_cspmu_find_cpu_container(
1122				    cpu, apmt_node->proc_affinity))
1123				continue;
1124
1125			cpumask_set_cpu(cpu, &cspmu->associated_cpus);
1126		}
1127	}
1128
1129	if (cpumask_empty(&cspmu->associated_cpus)) {
1130		dev_dbg(dev, "No cpu associated with the PMU\n");
1131		return -ENODEV;
1132	}
1133
1134	return 0;
1135}
1136
1137static int arm_cspmu_register_pmu(struct arm_cspmu *cspmu)
1138{
1139	int ret, capabilities;
1140	struct attribute_group **attr_groups;
1141
1142	attr_groups = arm_cspmu_alloc_attr_group(cspmu);
1143	if (!attr_groups)
1144		return -ENOMEM;
1145
1146	ret = cpuhp_state_add_instance(arm_cspmu_cpuhp_state,
1147				       &cspmu->cpuhp_node);
1148	if (ret)
1149		return ret;
1150
1151	capabilities = PERF_PMU_CAP_NO_EXCLUDE;
1152	if (cspmu->irq == 0)
1153		capabilities |= PERF_PMU_CAP_NO_INTERRUPT;
1154
1155	cspmu->pmu = (struct pmu){
1156		.task_ctx_nr	= perf_invalid_context,
1157		.module		= THIS_MODULE,
1158		.pmu_enable	= arm_cspmu_enable,
1159		.pmu_disable	= arm_cspmu_disable,
1160		.event_init	= arm_cspmu_event_init,
1161		.add		= arm_cspmu_add,
1162		.del		= arm_cspmu_del,
1163		.start		= arm_cspmu_start,
1164		.stop		= arm_cspmu_stop,
1165		.read		= arm_cspmu_read,
1166		.attr_groups	= (const struct attribute_group **)attr_groups,
1167		.capabilities	= capabilities,
1168	};
1169
1170	/* Hardware counter init */
1171	arm_cspmu_stop_counters(cspmu);
1172	arm_cspmu_reset_counters(cspmu);
1173
1174	ret = perf_pmu_register(&cspmu->pmu, cspmu->name, -1);
1175	if (ret) {
1176		cpuhp_state_remove_instance(arm_cspmu_cpuhp_state,
1177					    &cspmu->cpuhp_node);
1178	}
1179
1180	return ret;
1181}
1182
1183static int arm_cspmu_device_probe(struct platform_device *pdev)
1184{
1185	int ret;
1186	struct arm_cspmu *cspmu;
1187
1188	cspmu = arm_cspmu_alloc(pdev);
1189	if (!cspmu)
1190		return -ENOMEM;
1191
1192	ret = arm_cspmu_init_mmio(cspmu);
1193	if (ret)
1194		return ret;
1195
1196	ret = arm_cspmu_request_irq(cspmu);
1197	if (ret)
1198		return ret;
1199
1200	ret = arm_cspmu_get_cpus(cspmu);
1201	if (ret)
1202		return ret;
1203
1204	ret = arm_cspmu_register_pmu(cspmu);
1205	if (ret)
1206		return ret;
1207
1208	return 0;
1209}
1210
1211static int arm_cspmu_device_remove(struct platform_device *pdev)
1212{
1213	struct arm_cspmu *cspmu = platform_get_drvdata(pdev);
1214
1215	perf_pmu_unregister(&cspmu->pmu);
1216	cpuhp_state_remove_instance(arm_cspmu_cpuhp_state, &cspmu->cpuhp_node);
1217
1218	return 0;
1219}
1220
1221static struct platform_driver arm_cspmu_driver = {
1222	.driver = {
1223			.name = DRVNAME,
1224			.suppress_bind_attrs = true,
1225		},
1226	.probe = arm_cspmu_device_probe,
1227	.remove = arm_cspmu_device_remove,
1228};
1229
1230static void arm_cspmu_set_active_cpu(int cpu, struct arm_cspmu *cspmu)
1231{
1232	cpumask_set_cpu(cpu, &cspmu->active_cpu);
1233	WARN_ON(irq_set_affinity(cspmu->irq, &cspmu->active_cpu));
1234}
1235
1236static int arm_cspmu_cpu_online(unsigned int cpu, struct hlist_node *node)
1237{
1238	struct arm_cspmu *cspmu =
1239		hlist_entry_safe(node, struct arm_cspmu, cpuhp_node);
1240
1241	if (!cpumask_test_cpu(cpu, &cspmu->associated_cpus))
1242		return 0;
1243
1244	/* If the PMU is already managed, there is nothing to do */
1245	if (!cpumask_empty(&cspmu->active_cpu))
1246		return 0;
1247
1248	/* Use this CPU for event counting */
1249	arm_cspmu_set_active_cpu(cpu, cspmu);
1250
1251	return 0;
1252}
1253
1254static int arm_cspmu_cpu_teardown(unsigned int cpu, struct hlist_node *node)
1255{
1256	int dst;
1257	struct cpumask online_supported;
1258
1259	struct arm_cspmu *cspmu =
1260		hlist_entry_safe(node, struct arm_cspmu, cpuhp_node);
1261
1262	/* Nothing to do if this CPU doesn't own the PMU */
1263	if (!cpumask_test_and_clear_cpu(cpu, &cspmu->active_cpu))
1264		return 0;
1265
1266	/* Choose a new CPU to migrate ownership of the PMU to */
1267	cpumask_and(&online_supported, &cspmu->associated_cpus,
1268		    cpu_online_mask);
1269	dst = cpumask_any_but(&online_supported, cpu);
1270	if (dst >= nr_cpu_ids)
1271		return 0;
1272
1273	/* Use this CPU for event counting */
1274	perf_pmu_migrate_context(&cspmu->pmu, cpu, dst);
1275	arm_cspmu_set_active_cpu(dst, cspmu);
1276
1277	return 0;
1278}
1279
1280static int __init arm_cspmu_init(void)
1281{
1282	int ret;
1283
1284	ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN,
1285					"perf/arm/cspmu:online",
1286					arm_cspmu_cpu_online,
1287					arm_cspmu_cpu_teardown);
1288	if (ret < 0)
1289		return ret;
1290	arm_cspmu_cpuhp_state = ret;
1291	return platform_driver_register(&arm_cspmu_driver);
1292}
1293
1294static void __exit arm_cspmu_exit(void)
1295{
1296	platform_driver_unregister(&arm_cspmu_driver);
1297	cpuhp_remove_multi_state(arm_cspmu_cpuhp_state);
1298}
1299
1300module_init(arm_cspmu_init);
1301module_exit(arm_cspmu_exit);
1302
1303MODULE_LICENSE("GPL v2");