1/*
2 * PMU support
3 *
4 * Copyright (C) 2012 ARM Limited
5 * Author: Will Deacon <will.deacon@arm.com>
6 *
7 * This code is based heavily on the ARMv7 perf event code.
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
20 */
21#define pr_fmt(fmt) "hw perfevents: " fmt
22
23#include <linux/bitmap.h>
24#include <linux/interrupt.h>
25#include <linux/irq.h>
26#include <linux/kernel.h>
27#include <linux/export.h>
28#include <linux/perf_event.h>
29#include <linux/platform_device.h>
30#include <linux/spinlock.h>
31#include <linux/uaccess.h>
32
33#include <asm/cputype.h>
34#include <asm/irq.h>
35#include <asm/irq_regs.h>
36#include <asm/pmu.h>
37#include <asm/stacktrace.h>
38
39/*
40 * ARMv8 supports a maximum of 32 events.
41 * The cycle counter is included in this total.
42 */
43#define ARMPMU_MAX_HWEVENTS		32
44
45static DEFINE_PER_CPU(struct perf_event * [ARMPMU_MAX_HWEVENTS], hw_events);
46static DEFINE_PER_CPU(unsigned long [BITS_TO_LONGS(ARMPMU_MAX_HWEVENTS)], used_mask);
47static DEFINE_PER_CPU(struct pmu_hw_events, cpu_hw_events);
48
49#define to_arm_pmu(p) (container_of(p, struct arm_pmu, pmu))
50
51/* Set at runtime when we know what CPU type we are. */
52static struct arm_pmu *cpu_pmu;
53
54int
55armpmu_get_max_events(void)
56{
57	int max_events = 0;
58
59	if (cpu_pmu != NULL)
60		max_events = cpu_pmu->num_events;
61
62	return max_events;
63}
64EXPORT_SYMBOL_GPL(armpmu_get_max_events);
65
66int perf_num_counters(void)
67{
68	return armpmu_get_max_events();
69}
70EXPORT_SYMBOL_GPL(perf_num_counters);
71
72#define HW_OP_UNSUPPORTED		0xFFFF
73
74#define C(_x) \
75	PERF_COUNT_HW_CACHE_##_x
76
77#define CACHE_OP_UNSUPPORTED		0xFFFF
78
79static int
80armpmu_map_cache_event(const unsigned (*cache_map)
81				      [PERF_COUNT_HW_CACHE_MAX]
82				      [PERF_COUNT_HW_CACHE_OP_MAX]
83				      [PERF_COUNT_HW_CACHE_RESULT_MAX],
84		       u64 config)
85{
86	unsigned int cache_type, cache_op, cache_result, ret;
87
88	cache_type = (config >>  0) & 0xff;
89	if (cache_type >= PERF_COUNT_HW_CACHE_MAX)
90		return -EINVAL;
91
92	cache_op = (config >>  8) & 0xff;
93	if (cache_op >= PERF_COUNT_HW_CACHE_OP_MAX)
94		return -EINVAL;
95
96	cache_result = (config >> 16) & 0xff;
97	if (cache_result >= PERF_COUNT_HW_CACHE_RESULT_MAX)
98		return -EINVAL;
99
100	ret = (int)(*cache_map)[cache_type][cache_op][cache_result];
101
102	if (ret == CACHE_OP_UNSUPPORTED)
103		return -ENOENT;
104
105	return ret;
106}
107
108static int
109armpmu_map_event(const unsigned (*event_map)[PERF_COUNT_HW_MAX], u64 config)
110{
111	int mapping;
112
113	if (config >= PERF_COUNT_HW_MAX)
114		return -EINVAL;
115
116	mapping = (*event_map)[config];
117	return mapping == HW_OP_UNSUPPORTED ? -ENOENT : mapping;
118}
119
120static int
121armpmu_map_raw_event(u32 raw_event_mask, u64 config)
122{
123	return (int)(config & raw_event_mask);
124}
125
126static int map_cpu_event(struct perf_event *event,
127			 const unsigned (*event_map)[PERF_COUNT_HW_MAX],
128			 const unsigned (*cache_map)
129					[PERF_COUNT_HW_CACHE_MAX]
130					[PERF_COUNT_HW_CACHE_OP_MAX]
131					[PERF_COUNT_HW_CACHE_RESULT_MAX],
132			 u32 raw_event_mask)
133{
134	u64 config = event->attr.config;
135
136	switch (event->attr.type) {
137	case PERF_TYPE_HARDWARE:
138		return armpmu_map_event(event_map, config);
139	case PERF_TYPE_HW_CACHE:
140		return armpmu_map_cache_event(cache_map, config);
141	case PERF_TYPE_RAW:
142		return armpmu_map_raw_event(raw_event_mask, config);
143	}
144
145	return -ENOENT;
146}
147
148int
149armpmu_event_set_period(struct perf_event *event,
150			struct hw_perf_event *hwc,
151			int idx)
152{
153	struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
154	s64 left = local64_read(&hwc->period_left);
155	s64 period = hwc->sample_period;
156	int ret = 0;
157
158	if (unlikely(left <= -period)) {
159		left = period;
160		local64_set(&hwc->period_left, left);
161		hwc->last_period = period;
162		ret = 1;
163	}
164
165	if (unlikely(left <= 0)) {
166		left += period;
167		local64_set(&hwc->period_left, left);
168		hwc->last_period = period;
169		ret = 1;
170	}
171
172	if (left > (s64)armpmu->max_period)
173		left = armpmu->max_period;
174
175	local64_set(&hwc->prev_count, (u64)-left);
176
177	armpmu->write_counter(idx, (u64)(-left) & 0xffffffff);
178
179	perf_event_update_userpage(event);
180
181	return ret;
182}
183
184u64
185armpmu_event_update(struct perf_event *event,
186		    struct hw_perf_event *hwc,
187		    int idx)
188{
189	struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
190	u64 delta, prev_raw_count, new_raw_count;
191
192again:
193	prev_raw_count = local64_read(&hwc->prev_count);
194	new_raw_count = armpmu->read_counter(idx);
195
196	if (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
197			     new_raw_count) != prev_raw_count)
198		goto again;
199
200	delta = (new_raw_count - prev_raw_count) & armpmu->max_period;
201
202	local64_add(delta, &event->count);
203	local64_sub(delta, &hwc->period_left);
204
205	return new_raw_count;
206}
207
208static void
209armpmu_read(struct perf_event *event)
210{
211	struct hw_perf_event *hwc = &event->hw;
212
213	/* Don't read disabled counters! */
214	if (hwc->idx < 0)
215		return;
216
217	armpmu_event_update(event, hwc, hwc->idx);
218}
219
220static void
221armpmu_stop(struct perf_event *event, int flags)
222{
223	struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
224	struct hw_perf_event *hwc = &event->hw;
225
226	/*
227	 * ARM pmu always has to update the counter, so ignore
228	 * PERF_EF_UPDATE, see comments in armpmu_start().
229	 */
230	if (!(hwc->state & PERF_HES_STOPPED)) {
231		armpmu->disable(hwc, hwc->idx);
232		barrier(); /* why? */
233		armpmu_event_update(event, hwc, hwc->idx);
234		hwc->state |= PERF_HES_STOPPED | PERF_HES_UPTODATE;
235	}
236}
237
238static void
239armpmu_start(struct perf_event *event, int flags)
240{
241	struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
242	struct hw_perf_event *hwc = &event->hw;
243
244	/*
245	 * ARM pmu always has to reprogram the period, so ignore
246	 * PERF_EF_RELOAD, see the comment below.
247	 */
248	if (flags & PERF_EF_RELOAD)
249		WARN_ON_ONCE(!(hwc->state & PERF_HES_UPTODATE));
250
251	hwc->state = 0;
252	/*
253	 * Set the period again. Some counters can't be stopped, so when we
254	 * were stopped we simply disabled the IRQ source and the counter
255	 * may have been left counting. If we don't do this step then we may
256	 * get an interrupt too soon or *way* too late if the overflow has
257	 * happened since disabling.
258	 */
259	armpmu_event_set_period(event, hwc, hwc->idx);
260	armpmu->enable(hwc, hwc->idx);
261}
262
263static void
264armpmu_del(struct perf_event *event, int flags)
265{
266	struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
267	struct pmu_hw_events *hw_events = armpmu->get_hw_events();
268	struct hw_perf_event *hwc = &event->hw;
269	int idx = hwc->idx;
270
271	WARN_ON(idx < 0);
272
273	armpmu_stop(event, PERF_EF_UPDATE);
274	hw_events->events[idx] = NULL;
275	clear_bit(idx, hw_events->used_mask);
276
277	perf_event_update_userpage(event);
278}
279
280static int
281armpmu_add(struct perf_event *event, int flags)
282{
283	struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
284	struct pmu_hw_events *hw_events = armpmu->get_hw_events();
285	struct hw_perf_event *hwc = &event->hw;
286	int idx;
287	int err = 0;
288
289	perf_pmu_disable(event->pmu);
290
291	/* If we don't have a space for the counter then finish early. */
292	idx = armpmu->get_event_idx(hw_events, hwc);
293	if (idx < 0) {
294		err = idx;
295		goto out;
296	}
297
298	/*
299	 * If there is an event in the counter we are going to use then make
300	 * sure it is disabled.
301	 */
302	event->hw.idx = idx;
303	armpmu->disable(hwc, idx);
304	hw_events->events[idx] = event;
305
306	hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
307	if (flags & PERF_EF_START)
308		armpmu_start(event, PERF_EF_RELOAD);
309
310	/* Propagate our changes to the userspace mapping. */
311	perf_event_update_userpage(event);
312
313out:
314	perf_pmu_enable(event->pmu);
315	return err;
316}
317
318static int
319validate_event(struct pmu_hw_events *hw_events,
320	       struct perf_event *event)
321{
322	struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
323	struct hw_perf_event fake_event = event->hw;
324	struct pmu *leader_pmu = event->group_leader->pmu;
325
326	if (is_software_event(event))
327		return 1;
328
329	if (event->pmu != leader_pmu || event->state < PERF_EVENT_STATE_OFF)
330		return 1;
331
332	if (event->state == PERF_EVENT_STATE_OFF && !event->attr.enable_on_exec)
333		return 1;
334
335	return armpmu->get_event_idx(hw_events, &fake_event) >= 0;
336}
337
338static int
339validate_group(struct perf_event *event)
340{
341	struct perf_event *sibling, *leader = event->group_leader;
342	struct pmu_hw_events fake_pmu;
343	DECLARE_BITMAP(fake_used_mask, ARMPMU_MAX_HWEVENTS);
344
345	/*
346	 * Initialise the fake PMU. We only need to populate the
347	 * used_mask for the purposes of validation.
348	 */
349	memset(fake_used_mask, 0, sizeof(fake_used_mask));
350	fake_pmu.used_mask = fake_used_mask;
351
352	if (!validate_event(&fake_pmu, leader))
353		return -EINVAL;
354
355	list_for_each_entry(sibling, &leader->sibling_list, group_entry) {
356		if (!validate_event(&fake_pmu, sibling))
357			return -EINVAL;
358	}
359
360	if (!validate_event(&fake_pmu, event))
361		return -EINVAL;
362
363	return 0;
364}
365
366static void
367armpmu_disable_percpu_irq(void *data)
368{
369	unsigned int irq = *(unsigned int *)data;
370	disable_percpu_irq(irq);
371}
372
373static void
374armpmu_release_hardware(struct arm_pmu *armpmu)
375{
376	int irq;
377	unsigned int i, irqs;
378	struct platform_device *pmu_device = armpmu->plat_device;
379
380	irqs = min(pmu_device->num_resources, num_possible_cpus());
381	if (!irqs)
382		return;
383
384	irq = platform_get_irq(pmu_device, 0);
385	if (irq <= 0)
386		return;
387
388	if (irq_is_percpu(irq)) {
389		on_each_cpu(armpmu_disable_percpu_irq, &irq, 1);
390		free_percpu_irq(irq, &cpu_hw_events);
391	} else {
392		for (i = 0; i < irqs; ++i) {
393			if (!cpumask_test_and_clear_cpu(i, &armpmu->active_irqs))
394				continue;
395			irq = platform_get_irq(pmu_device, i);
396			if (irq > 0)
397				free_irq(irq, armpmu);
398		}
399	}
400}
401
402static void
403armpmu_enable_percpu_irq(void *data)
404{
405	unsigned int irq = *(unsigned int *)data;
406	enable_percpu_irq(irq, IRQ_TYPE_NONE);
407}
408
409static int
410armpmu_reserve_hardware(struct arm_pmu *armpmu)
411{
412	int err, irq;
413	unsigned int i, irqs;
414	struct platform_device *pmu_device = armpmu->plat_device;
415
416	if (!pmu_device) {
417		pr_err("no PMU device registered\n");
418		return -ENODEV;
419	}
420
421	irqs = min(pmu_device->num_resources, num_possible_cpus());
422	if (!irqs) {
423		pr_err("no irqs for PMUs defined\n");
424		return -ENODEV;
425	}
426
427	irq = platform_get_irq(pmu_device, 0);
428	if (irq <= 0) {
429		pr_err("failed to get valid irq for PMU device\n");
430		return -ENODEV;
431	}
432
433	if (irq_is_percpu(irq)) {
434		err = request_percpu_irq(irq, armpmu->handle_irq,
435				"arm-pmu", &cpu_hw_events);
436
437		if (err) {
438			pr_err("unable to request percpu IRQ%d for ARM PMU counters\n",
439					irq);
440			armpmu_release_hardware(armpmu);
441			return err;
442		}
443
444		on_each_cpu(armpmu_enable_percpu_irq, &irq, 1);
445	} else {
446		for (i = 0; i < irqs; ++i) {
447			err = 0;
448			irq = platform_get_irq(pmu_device, i);
449			if (irq <= 0)
450				continue;
451
452			/*
453			 * If we have a single PMU interrupt that we can't shift,
454			 * assume that we're running on a uniprocessor machine and
455			 * continue. Otherwise, continue without this interrupt.
456			 */
457			if (irq_set_affinity(irq, cpumask_of(i)) && irqs > 1) {
458				pr_warning("unable to set irq affinity (irq=%d, cpu=%u)\n",
459						irq, i);
460				continue;
461			}
462
463			err = request_irq(irq, armpmu->handle_irq,
464					IRQF_NOBALANCING,
465					"arm-pmu", armpmu);
466			if (err) {
467				pr_err("unable to request IRQ%d for ARM PMU counters\n",
468						irq);
469				armpmu_release_hardware(armpmu);
470				return err;
471			}
472
473			cpumask_set_cpu(i, &armpmu->active_irqs);
474		}
475	}
476
477	return 0;
478}
479
480static void
481hw_perf_event_destroy(struct perf_event *event)
482{
483	struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
484	atomic_t *active_events	 = &armpmu->active_events;
485	struct mutex *pmu_reserve_mutex = &armpmu->reserve_mutex;
486
487	if (atomic_dec_and_mutex_lock(active_events, pmu_reserve_mutex)) {
488		armpmu_release_hardware(armpmu);
489		mutex_unlock(pmu_reserve_mutex);
490	}
491}
492
493static int
494event_requires_mode_exclusion(struct perf_event_attr *attr)
495{
496	return attr->exclude_idle || attr->exclude_user ||
497	       attr->exclude_kernel || attr->exclude_hv;
498}
499
500static int
501__hw_perf_event_init(struct perf_event *event)
502{
503	struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
504	struct hw_perf_event *hwc = &event->hw;
505	int mapping, err;
506
507	mapping = armpmu->map_event(event);
508
509	if (mapping < 0) {
510		pr_debug("event %x:%llx not supported\n", event->attr.type,
511			 event->attr.config);
512		return mapping;
513	}
514
515	/*
516	 * We don't assign an index until we actually place the event onto
517	 * hardware. Use -1 to signify that we haven't decided where to put it
518	 * yet. For SMP systems, each core has it's own PMU so we can't do any
519	 * clever allocation or constraints checking at this point.
520	 */
521	hwc->idx		= -1;
522	hwc->config_base	= 0;
523	hwc->config		= 0;
524	hwc->event_base		= 0;
525
526	/*
527	 * Check whether we need to exclude the counter from certain modes.
528	 */
529	if ((!armpmu->set_event_filter ||
530	     armpmu->set_event_filter(hwc, &event->attr)) &&
531	     event_requires_mode_exclusion(&event->attr)) {
532		pr_debug("ARM performance counters do not support mode exclusion\n");
533		return -EPERM;
534	}
535
536	/*
537	 * Store the event encoding into the config_base field.
538	 */
539	hwc->config_base	    |= (unsigned long)mapping;
540
541	if (!hwc->sample_period) {
542		/*
543		 * For non-sampling runs, limit the sample_period to half
544		 * of the counter width. That way, the new counter value
545		 * is far less likely to overtake the previous one unless
546		 * you have some serious IRQ latency issues.
547		 */
548		hwc->sample_period  = armpmu->max_period >> 1;
549		hwc->last_period    = hwc->sample_period;
550		local64_set(&hwc->period_left, hwc->sample_period);
551	}
552
553	err = 0;
554	if (event->group_leader != event) {
555		err = validate_group(event);
556		if (err)
557			return -EINVAL;
558	}
559
560	return err;
561}
562
563static int armpmu_event_init(struct perf_event *event)
564{
565	struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
566	int err = 0;
567	atomic_t *active_events = &armpmu->active_events;
568
569	if (armpmu->map_event(event) == -ENOENT)
570		return -ENOENT;
571
572	event->destroy = hw_perf_event_destroy;
573
574	if (!atomic_inc_not_zero(active_events)) {
575		mutex_lock(&armpmu->reserve_mutex);
576		if (atomic_read(active_events) == 0)
577			err = armpmu_reserve_hardware(armpmu);
578
579		if (!err)
580			atomic_inc(active_events);
581		mutex_unlock(&armpmu->reserve_mutex);
582	}
583
584	if (err)
585		return err;
586
587	err = __hw_perf_event_init(event);
588	if (err)
589		hw_perf_event_destroy(event);
590
591	return err;
592}
593
594static void armpmu_enable(struct pmu *pmu)
595{
596	struct arm_pmu *armpmu = to_arm_pmu(pmu);
597	struct pmu_hw_events *hw_events = armpmu->get_hw_events();
598	int enabled = bitmap_weight(hw_events->used_mask, armpmu->num_events);
599
600	if (enabled)
601		armpmu->start();
602}
603
604static void armpmu_disable(struct pmu *pmu)
605{
606	struct arm_pmu *armpmu = to_arm_pmu(pmu);
607	armpmu->stop();
608}
609
610static void __init armpmu_init(struct arm_pmu *armpmu)
611{
612	atomic_set(&armpmu->active_events, 0);
613	mutex_init(&armpmu->reserve_mutex);
614
615	armpmu->pmu = (struct pmu) {
616		.pmu_enable	= armpmu_enable,
617		.pmu_disable	= armpmu_disable,
618		.event_init	= armpmu_event_init,
619		.add		= armpmu_add,
620		.del		= armpmu_del,
621		.start		= armpmu_start,
622		.stop		= armpmu_stop,
623		.read		= armpmu_read,
624	};
625}
626
627int __init armpmu_register(struct arm_pmu *armpmu, char *name, int type)
628{
629	armpmu_init(armpmu);
630	return perf_pmu_register(&armpmu->pmu, name, type);
631}
632
633/*
634 * ARMv8 PMUv3 Performance Events handling code.
635 * Common event types.
636 */
637enum armv8_pmuv3_perf_types {
638	/* Required events. */
639	ARMV8_PMUV3_PERFCTR_PMNC_SW_INCR			= 0x00,
640	ARMV8_PMUV3_PERFCTR_L1_DCACHE_REFILL			= 0x03,
641	ARMV8_PMUV3_PERFCTR_L1_DCACHE_ACCESS			= 0x04,
642	ARMV8_PMUV3_PERFCTR_PC_BRANCH_MIS_PRED			= 0x10,
643	ARMV8_PMUV3_PERFCTR_CLOCK_CYCLES			= 0x11,
644	ARMV8_PMUV3_PERFCTR_PC_BRANCH_PRED			= 0x12,
645
646	/* At least one of the following is required. */
647	ARMV8_PMUV3_PERFCTR_INSTR_EXECUTED			= 0x08,
648	ARMV8_PMUV3_PERFCTR_OP_SPEC				= 0x1B,
649
650	/* Common architectural events. */
651	ARMV8_PMUV3_PERFCTR_MEM_READ				= 0x06,
652	ARMV8_PMUV3_PERFCTR_MEM_WRITE				= 0x07,
653	ARMV8_PMUV3_PERFCTR_EXC_TAKEN				= 0x09,
654	ARMV8_PMUV3_PERFCTR_EXC_EXECUTED			= 0x0A,
655	ARMV8_PMUV3_PERFCTR_CID_WRITE				= 0x0B,
656	ARMV8_PMUV3_PERFCTR_PC_WRITE				= 0x0C,
657	ARMV8_PMUV3_PERFCTR_PC_IMM_BRANCH			= 0x0D,
658	ARMV8_PMUV3_PERFCTR_PC_PROC_RETURN			= 0x0E,
659	ARMV8_PMUV3_PERFCTR_MEM_UNALIGNED_ACCESS		= 0x0F,
660	ARMV8_PMUV3_PERFCTR_TTBR_WRITE				= 0x1C,
661
662	/* Common microarchitectural events. */
663	ARMV8_PMUV3_PERFCTR_L1_ICACHE_REFILL			= 0x01,
664	ARMV8_PMUV3_PERFCTR_ITLB_REFILL				= 0x02,
665	ARMV8_PMUV3_PERFCTR_DTLB_REFILL				= 0x05,
666	ARMV8_PMUV3_PERFCTR_MEM_ACCESS				= 0x13,
667	ARMV8_PMUV3_PERFCTR_L1_ICACHE_ACCESS			= 0x14,
668	ARMV8_PMUV3_PERFCTR_L1_DCACHE_WB			= 0x15,
669	ARMV8_PMUV3_PERFCTR_L2_CACHE_ACCESS			= 0x16,
670	ARMV8_PMUV3_PERFCTR_L2_CACHE_REFILL			= 0x17,
671	ARMV8_PMUV3_PERFCTR_L2_CACHE_WB				= 0x18,
672	ARMV8_PMUV3_PERFCTR_BUS_ACCESS				= 0x19,
673	ARMV8_PMUV3_PERFCTR_MEM_ERROR				= 0x1A,
674	ARMV8_PMUV3_PERFCTR_BUS_CYCLES				= 0x1D,
675};
676
677/* PMUv3 HW events mapping. */
678static const unsigned armv8_pmuv3_perf_map[PERF_COUNT_HW_MAX] = {
679	[PERF_COUNT_HW_CPU_CYCLES]		= ARMV8_PMUV3_PERFCTR_CLOCK_CYCLES,
680	[PERF_COUNT_HW_INSTRUCTIONS]		= ARMV8_PMUV3_PERFCTR_INSTR_EXECUTED,
681	[PERF_COUNT_HW_CACHE_REFERENCES]	= ARMV8_PMUV3_PERFCTR_L1_DCACHE_ACCESS,
682	[PERF_COUNT_HW_CACHE_MISSES]		= ARMV8_PMUV3_PERFCTR_L1_DCACHE_REFILL,
683	[PERF_COUNT_HW_BRANCH_INSTRUCTIONS]	= HW_OP_UNSUPPORTED,
684	[PERF_COUNT_HW_BRANCH_MISSES]		= ARMV8_PMUV3_PERFCTR_PC_BRANCH_MIS_PRED,
685	[PERF_COUNT_HW_BUS_CYCLES]		= HW_OP_UNSUPPORTED,
686	[PERF_COUNT_HW_STALLED_CYCLES_FRONTEND]	= HW_OP_UNSUPPORTED,
687	[PERF_COUNT_HW_STALLED_CYCLES_BACKEND]	= HW_OP_UNSUPPORTED,
688};
689
690static const unsigned armv8_pmuv3_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
691						[PERF_COUNT_HW_CACHE_OP_MAX]
692						[PERF_COUNT_HW_CACHE_RESULT_MAX] = {
693	[C(L1D)] = {
694		[C(OP_READ)] = {
695			[C(RESULT_ACCESS)]	= ARMV8_PMUV3_PERFCTR_L1_DCACHE_ACCESS,
696			[C(RESULT_MISS)]	= ARMV8_PMUV3_PERFCTR_L1_DCACHE_REFILL,
697		},
698		[C(OP_WRITE)] = {
699			[C(RESULT_ACCESS)]	= ARMV8_PMUV3_PERFCTR_L1_DCACHE_ACCESS,
700			[C(RESULT_MISS)]	= ARMV8_PMUV3_PERFCTR_L1_DCACHE_REFILL,
701		},
702		[C(OP_PREFETCH)] = {
703			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
704			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
705		},
706	},
707	[C(L1I)] = {
708		[C(OP_READ)] = {
709			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
710			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
711		},
712		[C(OP_WRITE)] = {
713			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
714			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
715		},
716		[C(OP_PREFETCH)] = {
717			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
718			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
719		},
720	},
721	[C(LL)] = {
722		[C(OP_READ)] = {
723			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
724			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
725		},
726		[C(OP_WRITE)] = {
727			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
728			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
729		},
730		[C(OP_PREFETCH)] = {
731			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
732			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
733		},
734	},
735	[C(DTLB)] = {
736		[C(OP_READ)] = {
737			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
738			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
739		},
740		[C(OP_WRITE)] = {
741			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
742			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
743		},
744		[C(OP_PREFETCH)] = {
745			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
746			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
747		},
748	},
749	[C(ITLB)] = {
750		[C(OP_READ)] = {
751			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
752			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
753		},
754		[C(OP_WRITE)] = {
755			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
756			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
757		},
758		[C(OP_PREFETCH)] = {
759			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
760			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
761		},
762	},
763	[C(BPU)] = {
764		[C(OP_READ)] = {
765			[C(RESULT_ACCESS)]	= ARMV8_PMUV3_PERFCTR_PC_BRANCH_PRED,
766			[C(RESULT_MISS)]	= ARMV8_PMUV3_PERFCTR_PC_BRANCH_MIS_PRED,
767		},
768		[C(OP_WRITE)] = {
769			[C(RESULT_ACCESS)]	= ARMV8_PMUV3_PERFCTR_PC_BRANCH_PRED,
770			[C(RESULT_MISS)]	= ARMV8_PMUV3_PERFCTR_PC_BRANCH_MIS_PRED,
771		},
772		[C(OP_PREFETCH)] = {
773			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
774			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
775		},
776	},
777	[C(NODE)] = {
778		[C(OP_READ)] = {
779			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
780			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
781		},
782		[C(OP_WRITE)] = {
783			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
784			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
785		},
786		[C(OP_PREFETCH)] = {
787			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
788			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
789		},
790	},
791};
792
793/*
794 * Perf Events' indices
795 */
796#define	ARMV8_IDX_CYCLE_COUNTER	0
797#define	ARMV8_IDX_COUNTER0	1
798#define	ARMV8_IDX_COUNTER_LAST	(ARMV8_IDX_CYCLE_COUNTER + cpu_pmu->num_events - 1)
799
800#define	ARMV8_MAX_COUNTERS	32
801#define	ARMV8_COUNTER_MASK	(ARMV8_MAX_COUNTERS - 1)
802
803/*
804 * ARMv8 low level PMU access
805 */
806
807/*
808 * Perf Event to low level counters mapping
809 */
810#define	ARMV8_IDX_TO_COUNTER(x)	\
811	(((x) - ARMV8_IDX_COUNTER0) & ARMV8_COUNTER_MASK)
812
813/*
814 * Per-CPU PMCR: config reg
815 */
816#define ARMV8_PMCR_E		(1 << 0) /* Enable all counters */
817#define ARMV8_PMCR_P		(1 << 1) /* Reset all counters */
818#define ARMV8_PMCR_C		(1 << 2) /* Cycle counter reset */
819#define ARMV8_PMCR_D		(1 << 3) /* CCNT counts every 64th cpu cycle */
820#define ARMV8_PMCR_X		(1 << 4) /* Export to ETM */
821#define ARMV8_PMCR_DP		(1 << 5) /* Disable CCNT if non-invasive debug*/
822#define	ARMV8_PMCR_N_SHIFT	11	 /* Number of counters supported */
823#define	ARMV8_PMCR_N_MASK	0x1f
824#define	ARMV8_PMCR_MASK		0x3f	 /* Mask for writable bits */
825
826/*
827 * PMOVSR: counters overflow flag status reg
828 */
829#define	ARMV8_OVSR_MASK		0xffffffff	/* Mask for writable bits */
830#define	ARMV8_OVERFLOWED_MASK	ARMV8_OVSR_MASK
831
832/*
833 * PMXEVTYPER: Event selection reg
834 */
835#define	ARMV8_EVTYPE_MASK	0xc80003ff	/* Mask for writable bits */
836#define	ARMV8_EVTYPE_EVENT	0x3ff		/* Mask for EVENT bits */
837
838/*
839 * Event filters for PMUv3
840 */
841#define	ARMV8_EXCLUDE_EL1	(1 << 31)
842#define	ARMV8_EXCLUDE_EL0	(1 << 30)
843#define	ARMV8_INCLUDE_EL2	(1 << 27)
844
845static inline u32 armv8pmu_pmcr_read(void)
846{
847	u32 val;
848	asm volatile("mrs %0, pmcr_el0" : "=r" (val));
849	return val;
850}
851
852static inline void armv8pmu_pmcr_write(u32 val)
853{
854	val &= ARMV8_PMCR_MASK;
855	isb();
856	asm volatile("msr pmcr_el0, %0" :: "r" (val));
857}
858
859static inline int armv8pmu_has_overflowed(u32 pmovsr)
860{
861	return pmovsr & ARMV8_OVERFLOWED_MASK;
862}
863
864static inline int armv8pmu_counter_valid(int idx)
865{
866	return idx >= ARMV8_IDX_CYCLE_COUNTER && idx <= ARMV8_IDX_COUNTER_LAST;
867}
868
869static inline int armv8pmu_counter_has_overflowed(u32 pmnc, int idx)
870{
871	int ret = 0;
872	u32 counter;
873
874	if (!armv8pmu_counter_valid(idx)) {
875		pr_err("CPU%u checking wrong counter %d overflow status\n",
876			smp_processor_id(), idx);
877	} else {
878		counter = ARMV8_IDX_TO_COUNTER(idx);
879		ret = pmnc & BIT(counter);
880	}
881
882	return ret;
883}
884
885static inline int armv8pmu_select_counter(int idx)
886{
887	u32 counter;
888
889	if (!armv8pmu_counter_valid(idx)) {
890		pr_err("CPU%u selecting wrong PMNC counter %d\n",
891			smp_processor_id(), idx);
892		return -EINVAL;
893	}
894
895	counter = ARMV8_IDX_TO_COUNTER(idx);
896	asm volatile("msr pmselr_el0, %0" :: "r" (counter));
897	isb();
898
899	return idx;
900}
901
902static inline u32 armv8pmu_read_counter(int idx)
903{
904	u32 value = 0;
905
906	if (!armv8pmu_counter_valid(idx))
907		pr_err("CPU%u reading wrong counter %d\n",
908			smp_processor_id(), idx);
909	else if (idx == ARMV8_IDX_CYCLE_COUNTER)
910		asm volatile("mrs %0, pmccntr_el0" : "=r" (value));
911	else if (armv8pmu_select_counter(idx) == idx)
912		asm volatile("mrs %0, pmxevcntr_el0" : "=r" (value));
913
914	return value;
915}
916
917static inline void armv8pmu_write_counter(int idx, u32 value)
918{
919	if (!armv8pmu_counter_valid(idx))
920		pr_err("CPU%u writing wrong counter %d\n",
921			smp_processor_id(), idx);
922	else if (idx == ARMV8_IDX_CYCLE_COUNTER)
923		asm volatile("msr pmccntr_el0, %0" :: "r" (value));
924	else if (armv8pmu_select_counter(idx) == idx)
925		asm volatile("msr pmxevcntr_el0, %0" :: "r" (value));
926}
927
928static inline void armv8pmu_write_evtype(int idx, u32 val)
929{
930	if (armv8pmu_select_counter(idx) == idx) {
931		val &= ARMV8_EVTYPE_MASK;
932		asm volatile("msr pmxevtyper_el0, %0" :: "r" (val));
933	}
934}
935
936static inline int armv8pmu_enable_counter(int idx)
937{
938	u32 counter;
939
940	if (!armv8pmu_counter_valid(idx)) {
941		pr_err("CPU%u enabling wrong PMNC counter %d\n",
942			smp_processor_id(), idx);
943		return -EINVAL;
944	}
945
946	counter = ARMV8_IDX_TO_COUNTER(idx);
947	asm volatile("msr pmcntenset_el0, %0" :: "r" (BIT(counter)));
948	return idx;
949}
950
951static inline int armv8pmu_disable_counter(int idx)
952{
953	u32 counter;
954
955	if (!armv8pmu_counter_valid(idx)) {
956		pr_err("CPU%u disabling wrong PMNC counter %d\n",
957			smp_processor_id(), idx);
958		return -EINVAL;
959	}
960
961	counter = ARMV8_IDX_TO_COUNTER(idx);
962	asm volatile("msr pmcntenclr_el0, %0" :: "r" (BIT(counter)));
963	return idx;
964}
965
966static inline int armv8pmu_enable_intens(int idx)
967{
968	u32 counter;
969
970	if (!armv8pmu_counter_valid(idx)) {
971		pr_err("CPU%u enabling wrong PMNC counter IRQ enable %d\n",
972			smp_processor_id(), idx);
973		return -EINVAL;
974	}
975
976	counter = ARMV8_IDX_TO_COUNTER(idx);
977	asm volatile("msr pmintenset_el1, %0" :: "r" (BIT(counter)));
978	return idx;
979}
980
981static inline int armv8pmu_disable_intens(int idx)
982{
983	u32 counter;
984
985	if (!armv8pmu_counter_valid(idx)) {
986		pr_err("CPU%u disabling wrong PMNC counter IRQ enable %d\n",
987			smp_processor_id(), idx);
988		return -EINVAL;
989	}
990
991	counter = ARMV8_IDX_TO_COUNTER(idx);
992	asm volatile("msr pmintenclr_el1, %0" :: "r" (BIT(counter)));
993	isb();
994	/* Clear the overflow flag in case an interrupt is pending. */
995	asm volatile("msr pmovsclr_el0, %0" :: "r" (BIT(counter)));
996	isb();
997	return idx;
998}
999
1000static inline u32 armv8pmu_getreset_flags(void)
1001{
1002	u32 value;
1003
1004	/* Read */
1005	asm volatile("mrs %0, pmovsclr_el0" : "=r" (value));
1006
1007	/* Write to clear flags */
1008	value &= ARMV8_OVSR_MASK;
1009	asm volatile("msr pmovsclr_el0, %0" :: "r" (value));
1010
1011	return value;
1012}
1013
1014static void armv8pmu_enable_event(struct hw_perf_event *hwc, int idx)
1015{
1016	unsigned long flags;
1017	struct pmu_hw_events *events = cpu_pmu->get_hw_events();
1018
1019	/*
1020	 * Enable counter and interrupt, and set the counter to count
1021	 * the event that we're interested in.
1022	 */
1023	raw_spin_lock_irqsave(&events->pmu_lock, flags);
1024
1025	/*
1026	 * Disable counter
1027	 */
1028	armv8pmu_disable_counter(idx);
1029
1030	/*
1031	 * Set event (if destined for PMNx counters).
1032	 */
1033	armv8pmu_write_evtype(idx, hwc->config_base);
1034
1035	/*
1036	 * Enable interrupt for this counter
1037	 */
1038	armv8pmu_enable_intens(idx);
1039
1040	/*
1041	 * Enable counter
1042	 */
1043	armv8pmu_enable_counter(idx);
1044
1045	raw_spin_unlock_irqrestore(&events->pmu_lock, flags);
1046}
1047
1048static void armv8pmu_disable_event(struct hw_perf_event *hwc, int idx)
1049{
1050	unsigned long flags;
1051	struct pmu_hw_events *events = cpu_pmu->get_hw_events();
1052
1053	/*
1054	 * Disable counter and interrupt
1055	 */
1056	raw_spin_lock_irqsave(&events->pmu_lock, flags);
1057
1058	/*
1059	 * Disable counter
1060	 */
1061	armv8pmu_disable_counter(idx);
1062
1063	/*
1064	 * Disable interrupt for this counter
1065	 */
1066	armv8pmu_disable_intens(idx);
1067
1068	raw_spin_unlock_irqrestore(&events->pmu_lock, flags);
1069}
1070
1071static irqreturn_t armv8pmu_handle_irq(int irq_num, void *dev)
1072{
1073	u32 pmovsr;
1074	struct perf_sample_data data;
1075	struct pmu_hw_events *cpuc;
1076	struct pt_regs *regs;
1077	int idx;
1078
1079	/*
1080	 * Get and reset the IRQ flags
1081	 */
1082	pmovsr = armv8pmu_getreset_flags();
1083
1084	/*
1085	 * Did an overflow occur?
1086	 */
1087	if (!armv8pmu_has_overflowed(pmovsr))
1088		return IRQ_NONE;
1089
1090	/*
1091	 * Handle the counter(s) overflow(s)
1092	 */
1093	regs = get_irq_regs();
1094
1095	cpuc = this_cpu_ptr(&cpu_hw_events);
1096	for (idx = 0; idx < cpu_pmu->num_events; ++idx) {
1097		struct perf_event *event = cpuc->events[idx];
1098		struct hw_perf_event *hwc;
1099
1100		/* Ignore if we don't have an event. */
1101		if (!event)
1102			continue;
1103
1104		/*
1105		 * We have a single interrupt for all counters. Check that
1106		 * each counter has overflowed before we process it.
1107		 */
1108		if (!armv8pmu_counter_has_overflowed(pmovsr, idx))
1109			continue;
1110
1111		hwc = &event->hw;
1112		armpmu_event_update(event, hwc, idx);
1113		perf_sample_data_init(&data, 0, hwc->last_period);
1114		if (!armpmu_event_set_period(event, hwc, idx))
1115			continue;
1116
1117		if (perf_event_overflow(event, &data, regs))
1118			cpu_pmu->disable(hwc, idx);
1119	}
1120
1121	/*
1122	 * Handle the pending perf events.
1123	 *
1124	 * Note: this call *must* be run with interrupts disabled. For
1125	 * platforms that can have the PMU interrupts raised as an NMI, this
1126	 * will not work.
1127	 */
1128	irq_work_run();
1129
1130	return IRQ_HANDLED;
1131}
1132
1133static void armv8pmu_start(void)
1134{
1135	unsigned long flags;
1136	struct pmu_hw_events *events = cpu_pmu->get_hw_events();
1137
1138	raw_spin_lock_irqsave(&events->pmu_lock, flags);
1139	/* Enable all counters */
1140	armv8pmu_pmcr_write(armv8pmu_pmcr_read() | ARMV8_PMCR_E);
1141	raw_spin_unlock_irqrestore(&events->pmu_lock, flags);
1142}
1143
1144static void armv8pmu_stop(void)
1145{
1146	unsigned long flags;
1147	struct pmu_hw_events *events = cpu_pmu->get_hw_events();
1148
1149	raw_spin_lock_irqsave(&events->pmu_lock, flags);
1150	/* Disable all counters */
1151	armv8pmu_pmcr_write(armv8pmu_pmcr_read() & ~ARMV8_PMCR_E);
1152	raw_spin_unlock_irqrestore(&events->pmu_lock, flags);
1153}
1154
1155static int armv8pmu_get_event_idx(struct pmu_hw_events *cpuc,
1156				  struct hw_perf_event *event)
1157{
1158	int idx;
1159	unsigned long evtype = event->config_base & ARMV8_EVTYPE_EVENT;
1160
1161	/* Always place a cycle counter into the cycle counter. */
1162	if (evtype == ARMV8_PMUV3_PERFCTR_CLOCK_CYCLES) {
1163		if (test_and_set_bit(ARMV8_IDX_CYCLE_COUNTER, cpuc->used_mask))
1164			return -EAGAIN;
1165
1166		return ARMV8_IDX_CYCLE_COUNTER;
1167	}
1168
1169	/*
1170	 * For anything other than a cycle counter, try and use
1171	 * the events counters
1172	 */
1173	for (idx = ARMV8_IDX_COUNTER0; idx < cpu_pmu->num_events; ++idx) {
1174		if (!test_and_set_bit(idx, cpuc->used_mask))
1175			return idx;
1176	}
1177
1178	/* The counters are all in use. */
1179	return -EAGAIN;
1180}
1181
1182/*
1183 * Add an event filter to a given event. This will only work for PMUv2 PMUs.
1184 */
1185static int armv8pmu_set_event_filter(struct hw_perf_event *event,
1186				     struct perf_event_attr *attr)
1187{
1188	unsigned long config_base = 0;
1189
1190	if (attr->exclude_idle)
1191		return -EPERM;
1192	if (attr->exclude_user)
1193		config_base |= ARMV8_EXCLUDE_EL0;
1194	if (attr->exclude_kernel)
1195		config_base |= ARMV8_EXCLUDE_EL1;
1196	if (!attr->exclude_hv)
1197		config_base |= ARMV8_INCLUDE_EL2;
1198
1199	/*
1200	 * Install the filter into config_base as this is used to
1201	 * construct the event type.
1202	 */
1203	event->config_base = config_base;
1204
1205	return 0;
1206}
1207
1208static void armv8pmu_reset(void *info)
1209{
1210	u32 idx, nb_cnt = cpu_pmu->num_events;
1211
1212	/* The counter and interrupt enable registers are unknown at reset. */
1213	for (idx = ARMV8_IDX_CYCLE_COUNTER; idx < nb_cnt; ++idx)
1214		armv8pmu_disable_event(NULL, idx);
1215
1216	/* Initialize & Reset PMNC: C and P bits. */
1217	armv8pmu_pmcr_write(ARMV8_PMCR_P | ARMV8_PMCR_C);
1218
1219	/* Disable access from userspace. */
1220	asm volatile("msr pmuserenr_el0, %0" :: "r" (0));
1221}
1222
1223static int armv8_pmuv3_map_event(struct perf_event *event)
1224{
1225	return map_cpu_event(event, &armv8_pmuv3_perf_map,
1226				&armv8_pmuv3_perf_cache_map,
1227				ARMV8_EVTYPE_EVENT);
1228}
1229
1230static struct arm_pmu armv8pmu = {
1231	.handle_irq		= armv8pmu_handle_irq,
1232	.enable			= armv8pmu_enable_event,
1233	.disable		= armv8pmu_disable_event,
1234	.read_counter		= armv8pmu_read_counter,
1235	.write_counter		= armv8pmu_write_counter,
1236	.get_event_idx		= armv8pmu_get_event_idx,
1237	.start			= armv8pmu_start,
1238	.stop			= armv8pmu_stop,
1239	.reset			= armv8pmu_reset,
1240	.max_period		= (1LLU << 32) - 1,
1241};
1242
1243static u32 __init armv8pmu_read_num_pmnc_events(void)
1244{
1245	u32 nb_cnt;
1246
1247	/* Read the nb of CNTx counters supported from PMNC */
1248	nb_cnt = (armv8pmu_pmcr_read() >> ARMV8_PMCR_N_SHIFT) & ARMV8_PMCR_N_MASK;
1249
1250	/* Add the CPU cycles counter and return */
1251	return nb_cnt + 1;
1252}
1253
1254static struct arm_pmu *__init armv8_pmuv3_pmu_init(void)
1255{
1256	armv8pmu.name			= "arm/armv8-pmuv3";
1257	armv8pmu.map_event		= armv8_pmuv3_map_event;
1258	armv8pmu.num_events		= armv8pmu_read_num_pmnc_events();
1259	armv8pmu.set_event_filter	= armv8pmu_set_event_filter;
1260	return &armv8pmu;
1261}
1262
1263/*
1264 * Ensure the PMU has sane values out of reset.
1265 * This requires SMP to be available, so exists as a separate initcall.
1266 */
1267static int __init
1268cpu_pmu_reset(void)
1269{
1270	if (cpu_pmu && cpu_pmu->reset)
1271		return on_each_cpu(cpu_pmu->reset, NULL, 1);
1272	return 0;
1273}
1274arch_initcall(cpu_pmu_reset);
1275
1276/*
1277 * PMU platform driver and devicetree bindings.
1278 */
1279static const struct of_device_id armpmu_of_device_ids[] = {
1280	{.compatible = "arm,armv8-pmuv3"},
1281	{},
1282};
1283
1284static int armpmu_device_probe(struct platform_device *pdev)
1285{
1286	if (!cpu_pmu)
1287		return -ENODEV;
1288
1289	cpu_pmu->plat_device = pdev;
1290	return 0;
1291}
1292
1293static struct platform_driver armpmu_driver = {
1294	.driver		= {
1295		.name	= "arm-pmu",
1296		.of_match_table = armpmu_of_device_ids,
1297	},
1298	.probe		= armpmu_device_probe,
1299};
1300
1301static int __init register_pmu_driver(void)
1302{
1303	return platform_driver_register(&armpmu_driver);
1304}
1305device_initcall(register_pmu_driver);
1306
1307static struct pmu_hw_events *armpmu_get_cpu_events(void)
1308{
1309	return this_cpu_ptr(&cpu_hw_events);
1310}
1311
1312static void __init cpu_pmu_init(struct arm_pmu *armpmu)
1313{
1314	int cpu;
1315	for_each_possible_cpu(cpu) {
1316		struct pmu_hw_events *events = &per_cpu(cpu_hw_events, cpu);
1317		events->events = per_cpu(hw_events, cpu);
1318		events->used_mask = per_cpu(used_mask, cpu);
1319		raw_spin_lock_init(&events->pmu_lock);
1320	}
1321	armpmu->get_hw_events = armpmu_get_cpu_events;
1322}
1323
1324static int __init init_hw_perf_events(void)
1325{
1326	u64 dfr = read_cpuid(ID_AA64DFR0_EL1);
1327
1328	switch ((dfr >> 8) & 0xf) {
1329	case 0x1:	/* PMUv3 */
1330		cpu_pmu = armv8_pmuv3_pmu_init();
1331		break;
1332	}
1333
1334	if (cpu_pmu) {
1335		pr_info("enabled with %s PMU driver, %d counters available\n",
1336			cpu_pmu->name, cpu_pmu->num_events);
1337		cpu_pmu_init(cpu_pmu);
1338		armpmu_register(cpu_pmu, "cpu", PERF_TYPE_RAW);
1339	} else {
1340		pr_info("no hardware support available\n");
1341	}
1342
1343	return 0;
1344}
1345early_initcall(init_hw_perf_events);
1346
1347/*
1348 * Callchain handling code.
1349 */
1350struct frame_tail {
1351	struct frame_tail	__user *fp;
1352	unsigned long		lr;
1353} __attribute__((packed));
1354
1355/*
1356 * Get the return address for a single stackframe and return a pointer to the
1357 * next frame tail.
1358 */
1359static struct frame_tail __user *
1360user_backtrace(struct frame_tail __user *tail,
1361	       struct perf_callchain_entry *entry)
1362{
1363	struct frame_tail buftail;
1364	unsigned long err;
1365
1366	/* Also check accessibility of one struct frame_tail beyond */
1367	if (!access_ok(VERIFY_READ, tail, sizeof(buftail)))
1368		return NULL;
1369
1370	pagefault_disable();
1371	err = __copy_from_user_inatomic(&buftail, tail, sizeof(buftail));
1372	pagefault_enable();
1373
1374	if (err)
1375		return NULL;
1376
1377	perf_callchain_store(entry, buftail.lr);
1378
1379	/*
1380	 * Frame pointers should strictly progress back up the stack
1381	 * (towards higher addresses).
1382	 */
1383	if (tail >= buftail.fp)
1384		return NULL;
1385
1386	return buftail.fp;
1387}
1388
1389#ifdef CONFIG_COMPAT
1390/*
1391 * The registers we're interested in are at the end of the variable
1392 * length saved register structure. The fp points at the end of this
1393 * structure so the address of this struct is:
1394 * (struct compat_frame_tail *)(xxx->fp)-1
1395 *
1396 * This code has been adapted from the ARM OProfile support.
1397 */
1398struct compat_frame_tail {
1399	compat_uptr_t	fp; /* a (struct compat_frame_tail *) in compat mode */
1400	u32		sp;
1401	u32		lr;
1402} __attribute__((packed));
1403
1404static struct compat_frame_tail __user *
1405compat_user_backtrace(struct compat_frame_tail __user *tail,
1406		      struct perf_callchain_entry *entry)
1407{
1408	struct compat_frame_tail buftail;
1409	unsigned long err;
1410
1411	/* Also check accessibility of one struct frame_tail beyond */
1412	if (!access_ok(VERIFY_READ, tail, sizeof(buftail)))
1413		return NULL;
1414
1415	pagefault_disable();
1416	err = __copy_from_user_inatomic(&buftail, tail, sizeof(buftail));
1417	pagefault_enable();
1418
1419	if (err)
1420		return NULL;
1421
1422	perf_callchain_store(entry, buftail.lr);
1423
1424	/*
1425	 * Frame pointers should strictly progress back up the stack
1426	 * (towards higher addresses).
1427	 */
1428	if (tail + 1 >= (struct compat_frame_tail __user *)
1429			compat_ptr(buftail.fp))
1430		return NULL;
1431
1432	return (struct compat_frame_tail __user *)compat_ptr(buftail.fp) - 1;
1433}
1434#endif /* CONFIG_COMPAT */
1435
1436void perf_callchain_user(struct perf_callchain_entry *entry,
1437			 struct pt_regs *regs)
1438{
1439	if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) {
1440		/* We don't support guest os callchain now */
1441		return;
1442	}
1443
1444	perf_callchain_store(entry, regs->pc);
1445
1446	if (!compat_user_mode(regs)) {
1447		/* AARCH64 mode */
1448		struct frame_tail __user *tail;
1449
1450		tail = (struct frame_tail __user *)regs->regs[29];
1451
1452		while (entry->nr < PERF_MAX_STACK_DEPTH &&
1453		       tail && !((unsigned long)tail & 0xf))
1454			tail = user_backtrace(tail, entry);
1455	} else {
1456#ifdef CONFIG_COMPAT
1457		/* AARCH32 compat mode */
1458		struct compat_frame_tail __user *tail;
1459
1460		tail = (struct compat_frame_tail __user *)regs->compat_fp - 1;
1461
1462		while ((entry->nr < PERF_MAX_STACK_DEPTH) &&
1463			tail && !((unsigned long)tail & 0x3))
1464			tail = compat_user_backtrace(tail, entry);
1465#endif
1466	}
1467}
1468
1469/*
1470 * Gets called by walk_stackframe() for every stackframe. This will be called
1471 * whist unwinding the stackframe and is like a subroutine return so we use
1472 * the PC.
1473 */
1474static int callchain_trace(struct stackframe *frame, void *data)
1475{
1476	struct perf_callchain_entry *entry = data;
1477	perf_callchain_store(entry, frame->pc);
1478	return 0;
1479}
1480
1481void perf_callchain_kernel(struct perf_callchain_entry *entry,
1482			   struct pt_regs *regs)
1483{
1484	struct stackframe frame;
1485
1486	if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) {
1487		/* We don't support guest os callchain now */
1488		return;
1489	}
1490
1491	frame.fp = regs->regs[29];
1492	frame.sp = regs->sp;
1493	frame.pc = regs->pc;
1494
1495	walk_stackframe(&frame, callchain_trace, entry);
1496}
1497
1498unsigned long perf_instruction_pointer(struct pt_regs *regs)
1499{
1500	if (perf_guest_cbs && perf_guest_cbs->is_in_guest())
1501		return perf_guest_cbs->get_guest_ip();
1502
1503	return instruction_pointer(regs);
1504}
1505
1506unsigned long perf_misc_flags(struct pt_regs *regs)
1507{
1508	int misc = 0;
1509
1510	if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) {
1511		if (perf_guest_cbs->is_user_mode())
1512			misc |= PERF_RECORD_MISC_GUEST_USER;
1513		else
1514			misc |= PERF_RECORD_MISC_GUEST_KERNEL;
1515	} else {
1516		if (user_mode(regs))
1517			misc |= PERF_RECORD_MISC_USER;
1518		else
1519			misc |= PERF_RECORD_MISC_KERNEL;
1520	}
1521
1522	return misc;
1523}
1524