1// SPDX-License-Identifier: GPL-2.0+
2//
3// Linux performance counter support for ARC CPUs.
4// This code is inspired by the perf support of various other architectures.
5//
6// Copyright (C) 2013-2018 Synopsys, Inc. (www.synopsys.com)
7
8#include <linux/errno.h>
9#include <linux/interrupt.h>
10#include <linux/module.h>
11#include <linux/of.h>
12#include <linux/perf_event.h>
13#include <linux/platform_device.h>
14#include <asm/arcregs.h>
15#include <asm/stacktrace.h>
16
17/* HW holds 8 symbols + one for null terminator */
18#define ARCPMU_EVENT_NAME_LEN	9
19
20/*
21 * Some ARC pct quirks:
22 *
23 * PERF_COUNT_HW_STALLED_CYCLES_BACKEND
24 * PERF_COUNT_HW_STALLED_CYCLES_FRONTEND
25 *	The ARC 700 can either measure stalls per pipeline stage, or all stalls
26 *	combined; for now we assign all stalls to STALLED_CYCLES_BACKEND
27 *	and all pipeline flushes (e.g. caused by mispredicts, etc.) to
28 *	STALLED_CYCLES_FRONTEND.
29 *
30 *	We could start multiple performance counters and combine everything
31 *	afterwards, but that makes it complicated.
32 *
33 *	Note that I$ cache misses aren't counted by either of the two!
34 */
35
36/*
37 * ARC PCT has hardware conditions with fixed "names" but variable "indexes"
38 * (based on a specific RTL build)
39 * Below is the static map between perf generic/arc specific event_id and
40 * h/w condition names.
41 * At the time of probe, we loop thru each index and find its name to
42 * complete the mapping of perf event_id to h/w index as latter is needed
43 * to program the counter really
44 */
45static const char * const arc_pmu_ev_hw_map[] = {
46	/* count cycles */
47	[PERF_COUNT_HW_CPU_CYCLES] = "crun",
48	[PERF_COUNT_HW_REF_CPU_CYCLES] = "crun",
49	[PERF_COUNT_HW_BUS_CYCLES] = "crun",
50
51	[PERF_COUNT_HW_STALLED_CYCLES_FRONTEND] = "bflush",
52	[PERF_COUNT_HW_STALLED_CYCLES_BACKEND] = "bstall",
53
54	/* counts condition */
55	[PERF_COUNT_HW_INSTRUCTIONS] = "iall",
56	/* All jump instructions that are taken */
57	[PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = "ijmptak",
58#ifdef CONFIG_ISA_ARCV2
59	[PERF_COUNT_HW_BRANCH_MISSES] = "bpmp",
60#else
61	[PERF_COUNT_ARC_BPOK]         = "bpok",	  /* NP-NT, PT-T, PNT-NT */
62	[PERF_COUNT_HW_BRANCH_MISSES] = "bpfail", /* NP-T, PT-NT, PNT-T */
63#endif
64	[PERF_COUNT_ARC_LDC] = "imemrdc",	/* Instr: mem read cached */
65	[PERF_COUNT_ARC_STC] = "imemwrc",	/* Instr: mem write cached */
66
67	[PERF_COUNT_ARC_DCLM] = "dclm",		/* D-cache Load Miss */
68	[PERF_COUNT_ARC_DCSM] = "dcsm",		/* D-cache Store Miss */
69	[PERF_COUNT_ARC_ICM] = "icm",		/* I-cache Miss */
70	[PERF_COUNT_ARC_EDTLB] = "edtlb",	/* D-TLB Miss */
71	[PERF_COUNT_ARC_EITLB] = "eitlb",	/* I-TLB Miss */
72
73	[PERF_COUNT_HW_CACHE_REFERENCES] = "imemrdc",	/* Instr: mem read cached */
74	[PERF_COUNT_HW_CACHE_MISSES] = "dclm",		/* D-cache Load Miss */
75};
76
77#define C(_x)			PERF_COUNT_HW_CACHE_##_x
78#define CACHE_OP_UNSUPPORTED	0xffff
79
80static const unsigned int arc_pmu_cache_map[C(MAX)][C(OP_MAX)][C(RESULT_MAX)] = {
81	[C(L1D)] = {
82		[C(OP_READ)] = {
83			[C(RESULT_ACCESS)]	= PERF_COUNT_ARC_LDC,
84			[C(RESULT_MISS)]	= PERF_COUNT_ARC_DCLM,
85		},
86		[C(OP_WRITE)] = {
87			[C(RESULT_ACCESS)]	= PERF_COUNT_ARC_STC,
88			[C(RESULT_MISS)]	= PERF_COUNT_ARC_DCSM,
89		},
90		[C(OP_PREFETCH)] = {
91			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
92			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
93		},
94	},
95	[C(L1I)] = {
96		[C(OP_READ)] = {
97			[C(RESULT_ACCESS)]	= PERF_COUNT_HW_INSTRUCTIONS,
98			[C(RESULT_MISS)]	= PERF_COUNT_ARC_ICM,
99		},
100		[C(OP_WRITE)] = {
101			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
102			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
103		},
104		[C(OP_PREFETCH)] = {
105			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
106			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
107		},
108	},
109	[C(LL)] = {
110		[C(OP_READ)] = {
111			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
112			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
113		},
114		[C(OP_WRITE)] = {
115			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
116			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
117		},
118		[C(OP_PREFETCH)] = {
119			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
120			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
121		},
122	},
123	[C(DTLB)] = {
124		[C(OP_READ)] = {
125			[C(RESULT_ACCESS)]	= PERF_COUNT_ARC_LDC,
126			[C(RESULT_MISS)]	= PERF_COUNT_ARC_EDTLB,
127		},
128			/* DTLB LD/ST Miss not segregated by h/w*/
129		[C(OP_WRITE)] = {
130			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
131			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
132		},
133		[C(OP_PREFETCH)] = {
134			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
135			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
136		},
137	},
138	[C(ITLB)] = {
139		[C(OP_READ)] = {
140			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
141			[C(RESULT_MISS)]	= PERF_COUNT_ARC_EITLB,
142		},
143		[C(OP_WRITE)] = {
144			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
145			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
146		},
147		[C(OP_PREFETCH)] = {
148			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
149			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
150		},
151	},
152	[C(BPU)] = {
153		[C(OP_READ)] = {
154			[C(RESULT_ACCESS)] = PERF_COUNT_HW_BRANCH_INSTRUCTIONS,
155			[C(RESULT_MISS)]	= PERF_COUNT_HW_BRANCH_MISSES,
156		},
157		[C(OP_WRITE)] = {
158			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
159			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
160		},
161		[C(OP_PREFETCH)] = {
162			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
163			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
164		},
165	},
166	[C(NODE)] = {
167		[C(OP_READ)] = {
168			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
169			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
170		},
171		[C(OP_WRITE)] = {
172			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
173			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
174		},
175		[C(OP_PREFETCH)] = {
176			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
177			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
178		},
179	},
180};
181
182enum arc_pmu_attr_groups {
183	ARCPMU_ATTR_GR_EVENTS,
184	ARCPMU_ATTR_GR_FORMATS,
185	ARCPMU_NR_ATTR_GR
186};
187
188struct arc_pmu_raw_event_entry {
189	char name[ARCPMU_EVENT_NAME_LEN];
190};
191
192struct arc_pmu {
193	struct pmu	pmu;
194	unsigned int	irq;
195	int		n_counters;
196	int		n_events;
197	u64		max_period;
198	int		ev_hw_idx[PERF_COUNT_ARC_HW_MAX];
199
200	struct arc_pmu_raw_event_entry	*raw_entry;
201	struct attribute		**attrs;
202	struct perf_pmu_events_attr	*attr;
203	const struct attribute_group	*attr_groups[ARCPMU_NR_ATTR_GR + 1];
204};
205
206struct arc_pmu_cpu {
207	/*
208	 * A 1 bit for an index indicates that the counter is being used for
209	 * an event. A 0 means that the counter can be used.
210	 */
211	unsigned long	used_mask[BITS_TO_LONGS(ARC_PERF_MAX_COUNTERS)];
212
213	/*
214	 * The events that are active on the PMU for the given index.
215	 */
216	struct perf_event *act_counter[ARC_PERF_MAX_COUNTERS];
217};
218
219struct arc_callchain_trace {
220	int depth;
221	void *perf_stuff;
222};
223
224static int callchain_trace(unsigned int addr, void *data)
225{
226	struct arc_callchain_trace *ctrl = data;
227	struct perf_callchain_entry_ctx *entry = ctrl->perf_stuff;
228
229	perf_callchain_store(entry, addr);
230
231	if (ctrl->depth++ < 3)
232		return 0;
233
234	return -1;
235}
236
237void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry,
238			   struct pt_regs *regs)
239{
240	struct arc_callchain_trace ctrl = {
241		.depth = 0,
242		.perf_stuff = entry,
243	};
244
245	arc_unwind_core(NULL, regs, callchain_trace, &ctrl);
246}
247
248void perf_callchain_user(struct perf_callchain_entry_ctx *entry,
249			 struct pt_regs *regs)
250{
251	/*
252	 * User stack can't be unwound trivially with kernel dwarf unwinder
253	 * So for now just record the user PC
254	 */
255	perf_callchain_store(entry, instruction_pointer(regs));
256}
257
258static struct arc_pmu *arc_pmu;
259static DEFINE_PER_CPU(struct arc_pmu_cpu, arc_pmu_cpu);
260
261/* read counter #idx; note that counter# != event# on ARC! */
262static u64 arc_pmu_read_counter(int idx)
263{
264	u32 tmp;
265	u64 result;
266
267	/*
268	 * ARC supports making 'snapshots' of the counters, so we don't
269	 * need to care about counters wrapping to 0 underneath our feet
270	 */
271	write_aux_reg(ARC_REG_PCT_INDEX, idx);
272	tmp = read_aux_reg(ARC_REG_PCT_CONTROL);
273	write_aux_reg(ARC_REG_PCT_CONTROL, tmp | ARC_REG_PCT_CONTROL_SN);
274	result = (u64) (read_aux_reg(ARC_REG_PCT_SNAPH)) << 32;
275	result |= read_aux_reg(ARC_REG_PCT_SNAPL);
276
277	return result;
278}
279
280static void arc_perf_event_update(struct perf_event *event,
281				  struct hw_perf_event *hwc, int idx)
282{
283	u64 prev_raw_count = local64_read(&hwc->prev_count);
284	u64 new_raw_count = arc_pmu_read_counter(idx);
285	s64 delta = new_raw_count - prev_raw_count;
286
287	/*
288	 * We aren't afraid of hwc->prev_count changing beneath our feet
289	 * because there's no way for us to re-enter this function anytime.
290	 */
291	local64_set(&hwc->prev_count, new_raw_count);
292	local64_add(delta, &event->count);
293	local64_sub(delta, &hwc->period_left);
294}
295
296static void arc_pmu_read(struct perf_event *event)
297{
298	arc_perf_event_update(event, &event->hw, event->hw.idx);
299}
300
301static int arc_pmu_cache_event(u64 config)
302{
303	unsigned int cache_type, cache_op, cache_result;
304	int ret;
305
306	cache_type	= (config >>  0) & 0xff;
307	cache_op	= (config >>  8) & 0xff;
308	cache_result	= (config >> 16) & 0xff;
309	if (cache_type >= PERF_COUNT_HW_CACHE_MAX)
310		return -EINVAL;
311	if (cache_op >= PERF_COUNT_HW_CACHE_OP_MAX)
312		return -EINVAL;
313	if (cache_result >= PERF_COUNT_HW_CACHE_RESULT_MAX)
314		return -EINVAL;
315
316	ret = arc_pmu_cache_map[cache_type][cache_op][cache_result];
317
318	if (ret == CACHE_OP_UNSUPPORTED)
319		return -ENOENT;
320
321	pr_debug("init cache event: type/op/result %d/%d/%d with h/w %d \'%s\'\n",
322		 cache_type, cache_op, cache_result, ret,
323		 arc_pmu_ev_hw_map[ret]);
324
325	return ret;
326}
327
328/* initializes hw_perf_event structure if event is supported */
329static int arc_pmu_event_init(struct perf_event *event)
330{
331	struct hw_perf_event *hwc = &event->hw;
332	int ret;
333
334	if (!is_sampling_event(event)) {
335		hwc->sample_period = arc_pmu->max_period;
336		hwc->last_period = hwc->sample_period;
337		local64_set(&hwc->period_left, hwc->sample_period);
338	}
339
340	hwc->config = 0;
341
342	if (is_isa_arcv2()) {
343		/* "exclude user" means "count only kernel" */
344		if (event->attr.exclude_user)
345			hwc->config |= ARC_REG_PCT_CONFIG_KERN;
346
347		/* "exclude kernel" means "count only user" */
348		if (event->attr.exclude_kernel)
349			hwc->config |= ARC_REG_PCT_CONFIG_USER;
350	}
351
352	switch (event->attr.type) {
353	case PERF_TYPE_HARDWARE:
354		if (event->attr.config >= PERF_COUNT_HW_MAX)
355			return -ENOENT;
356		if (arc_pmu->ev_hw_idx[event->attr.config] < 0)
357			return -ENOENT;
358		hwc->config |= arc_pmu->ev_hw_idx[event->attr.config];
359		pr_debug("init event %d with h/w %08x \'%s\'\n",
360			 (int)event->attr.config, (int)hwc->config,
361			 arc_pmu_ev_hw_map[event->attr.config]);
362		return 0;
363
364	case PERF_TYPE_HW_CACHE:
365		ret = arc_pmu_cache_event(event->attr.config);
366		if (ret < 0)
367			return ret;
368		hwc->config |= arc_pmu->ev_hw_idx[ret];
369		pr_debug("init cache event with h/w %08x \'%s\'\n",
370			 (int)hwc->config, arc_pmu_ev_hw_map[ret]);
371		return 0;
372
373	case PERF_TYPE_RAW:
374		if (event->attr.config >= arc_pmu->n_events)
375			return -ENOENT;
376
377		hwc->config |= event->attr.config;
378		pr_debug("init raw event with idx %lld \'%s\'\n",
379			 event->attr.config,
380			 arc_pmu->raw_entry[event->attr.config].name);
381
382		return 0;
383
384	default:
385		return -ENOENT;
386	}
387}
388
389/* starts all counters */
390static void arc_pmu_enable(struct pmu *pmu)
391{
392	u32 tmp;
393	tmp = read_aux_reg(ARC_REG_PCT_CONTROL);
394	write_aux_reg(ARC_REG_PCT_CONTROL, (tmp & 0xffff0000) | 0x1);
395}
396
397/* stops all counters */
398static void arc_pmu_disable(struct pmu *pmu)
399{
400	u32 tmp;
401	tmp = read_aux_reg(ARC_REG_PCT_CONTROL);
402	write_aux_reg(ARC_REG_PCT_CONTROL, (tmp & 0xffff0000) | 0x0);
403}
404
405static int arc_pmu_event_set_period(struct perf_event *event)
406{
407	struct hw_perf_event *hwc = &event->hw;
408	s64 left = local64_read(&hwc->period_left);
409	s64 period = hwc->sample_period;
410	int idx = hwc->idx;
411	int overflow = 0;
412	u64 value;
413
414	if (unlikely(left <= -period)) {
415		/* left underflowed by more than period. */
416		left = period;
417		local64_set(&hwc->period_left, left);
418		hwc->last_period = period;
419		overflow = 1;
420	} else if (unlikely(left <= 0)) {
421		/* left underflowed by less than period. */
422		left += period;
423		local64_set(&hwc->period_left, left);
424		hwc->last_period = period;
425		overflow = 1;
426	}
427
428	if (left > arc_pmu->max_period)
429		left = arc_pmu->max_period;
430
431	value = arc_pmu->max_period - left;
432	local64_set(&hwc->prev_count, value);
433
434	/* Select counter */
435	write_aux_reg(ARC_REG_PCT_INDEX, idx);
436
437	/* Write value */
438	write_aux_reg(ARC_REG_PCT_COUNTL, lower_32_bits(value));
439	write_aux_reg(ARC_REG_PCT_COUNTH, upper_32_bits(value));
440
441	perf_event_update_userpage(event);
442
443	return overflow;
444}
445
446/*
447 * Assigns hardware counter to hardware condition.
448 * Note that there is no separate start/stop mechanism;
449 * stopping is achieved by assigning the 'never' condition
450 */
451static void arc_pmu_start(struct perf_event *event, int flags)
452{
453	struct hw_perf_event *hwc = &event->hw;
454	int idx = hwc->idx;
455
456	if (WARN_ON_ONCE(idx == -1))
457		return;
458
459	if (flags & PERF_EF_RELOAD)
460		WARN_ON_ONCE(!(hwc->state & PERF_HES_UPTODATE));
461
462	hwc->state = 0;
463
464	arc_pmu_event_set_period(event);
465
466	/* Enable interrupt for this counter */
467	if (is_sampling_event(event))
468		write_aux_reg(ARC_REG_PCT_INT_CTRL,
469			      read_aux_reg(ARC_REG_PCT_INT_CTRL) | BIT(idx));
470
471	/* enable ARC pmu here */
472	write_aux_reg(ARC_REG_PCT_INDEX, idx);		/* counter # */
473	write_aux_reg(ARC_REG_PCT_CONFIG, hwc->config);	/* condition */
474}
475
476static void arc_pmu_stop(struct perf_event *event, int flags)
477{
478	struct hw_perf_event *hwc = &event->hw;
479	int idx = hwc->idx;
480
481	/* Disable interrupt for this counter */
482	if (is_sampling_event(event)) {
483		/*
484		 * Reset interrupt flag by writing of 1. This is required
485		 * to make sure pending interrupt was not left.
486		 */
487		write_aux_reg(ARC_REG_PCT_INT_ACT, BIT(idx));
488		write_aux_reg(ARC_REG_PCT_INT_CTRL,
489			      read_aux_reg(ARC_REG_PCT_INT_CTRL) & ~BIT(idx));
490	}
491
492	if (!(event->hw.state & PERF_HES_STOPPED)) {
493		/* stop hw counter here */
494		write_aux_reg(ARC_REG_PCT_INDEX, idx);
495
496		/* condition code #0 is always "never" */
497		write_aux_reg(ARC_REG_PCT_CONFIG, 0);
498
499		event->hw.state |= PERF_HES_STOPPED;
500	}
501
502	if ((flags & PERF_EF_UPDATE) &&
503	    !(event->hw.state & PERF_HES_UPTODATE)) {
504		arc_perf_event_update(event, &event->hw, idx);
505		event->hw.state |= PERF_HES_UPTODATE;
506	}
507}
508
509static void arc_pmu_del(struct perf_event *event, int flags)
510{
511	struct arc_pmu_cpu *pmu_cpu = this_cpu_ptr(&arc_pmu_cpu);
512
513	arc_pmu_stop(event, PERF_EF_UPDATE);
514	__clear_bit(event->hw.idx, pmu_cpu->used_mask);
515
516	pmu_cpu->act_counter[event->hw.idx] = 0;
517
518	perf_event_update_userpage(event);
519}
520
521/* allocate hardware counter and optionally start counting */
522static int arc_pmu_add(struct perf_event *event, int flags)
523{
524	struct arc_pmu_cpu *pmu_cpu = this_cpu_ptr(&arc_pmu_cpu);
525	struct hw_perf_event *hwc = &event->hw;
526	int idx;
527
528	idx = ffz(pmu_cpu->used_mask[0]);
529	if (idx == arc_pmu->n_counters)
530		return -EAGAIN;
531
532	__set_bit(idx, pmu_cpu->used_mask);
533	hwc->idx = idx;
534
535	write_aux_reg(ARC_REG_PCT_INDEX, idx);
536
537	pmu_cpu->act_counter[idx] = event;
538
539	if (is_sampling_event(event)) {
540		/* Mimic full counter overflow as other arches do */
541		write_aux_reg(ARC_REG_PCT_INT_CNTL,
542			      lower_32_bits(arc_pmu->max_period));
543		write_aux_reg(ARC_REG_PCT_INT_CNTH,
544			      upper_32_bits(arc_pmu->max_period));
545	}
546
547	write_aux_reg(ARC_REG_PCT_CONFIG, 0);
548	write_aux_reg(ARC_REG_PCT_COUNTL, 0);
549	write_aux_reg(ARC_REG_PCT_COUNTH, 0);
550	local64_set(&hwc->prev_count, 0);
551
552	hwc->state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
553	if (flags & PERF_EF_START)
554		arc_pmu_start(event, PERF_EF_RELOAD);
555
556	perf_event_update_userpage(event);
557
558	return 0;
559}
560
561#ifdef CONFIG_ISA_ARCV2
562static irqreturn_t arc_pmu_intr(int irq, void *dev)
563{
564	struct perf_sample_data data;
565	struct arc_pmu_cpu *pmu_cpu = this_cpu_ptr(&arc_pmu_cpu);
566	struct pt_regs *regs;
567	unsigned int active_ints;
568	int idx;
569
570	arc_pmu_disable(&arc_pmu->pmu);
571
572	active_ints = read_aux_reg(ARC_REG_PCT_INT_ACT);
573	if (!active_ints)
574		goto done;
575
576	regs = get_irq_regs();
577
578	do {
579		struct perf_event *event;
580		struct hw_perf_event *hwc;
581
582		idx = __ffs(active_ints);
583
584		/* Reset interrupt flag by writing of 1 */
585		write_aux_reg(ARC_REG_PCT_INT_ACT, BIT(idx));
586
587		/*
588		 * On reset of "interrupt active" bit corresponding
589		 * "interrupt enable" bit gets automatically reset as well.
590		 * Now we need to re-enable interrupt for the counter.
591		 */
592		write_aux_reg(ARC_REG_PCT_INT_CTRL,
593			read_aux_reg(ARC_REG_PCT_INT_CTRL) | BIT(idx));
594
595		event = pmu_cpu->act_counter[idx];
596		hwc = &event->hw;
597
598		WARN_ON_ONCE(hwc->idx != idx);
599
600		arc_perf_event_update(event, &event->hw, event->hw.idx);
601		perf_sample_data_init(&data, 0, hwc->last_period);
602		if (arc_pmu_event_set_period(event)) {
603			if (perf_event_overflow(event, &data, regs))
604				arc_pmu_stop(event, 0);
605		}
606
607		active_ints &= ~BIT(idx);
608	} while (active_ints);
609
610done:
611	arc_pmu_enable(&arc_pmu->pmu);
612
613	return IRQ_HANDLED;
614}
615#else
616
617static irqreturn_t arc_pmu_intr(int irq, void *dev)
618{
619	return IRQ_NONE;
620}
621
622#endif /* CONFIG_ISA_ARCV2 */
623
624static void arc_cpu_pmu_irq_init(void *data)
625{
626	int irq = *(int *)data;
627
628	enable_percpu_irq(irq, IRQ_TYPE_NONE);
629
630	/* Clear all pending interrupt flags */
631	write_aux_reg(ARC_REG_PCT_INT_ACT, 0xffffffff);
632}
633
634/* Event field occupies the bottom 15 bits of our config field */
635PMU_FORMAT_ATTR(event, "config:0-14");
636static struct attribute *arc_pmu_format_attrs[] = {
637	&format_attr_event.attr,
638	NULL,
639};
640
641static struct attribute_group arc_pmu_format_attr_gr = {
642	.name = "format",
643	.attrs = arc_pmu_format_attrs,
644};
645
646static ssize_t arc_pmu_events_sysfs_show(struct device *dev,
647					 struct device_attribute *attr,
648					 char *page)
649{
650	struct perf_pmu_events_attr *pmu_attr;
651
652	pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr);
653	return sprintf(page, "event=0x%04llx\n", pmu_attr->id);
654}
655
656/*
657 * We don't add attrs here as we don't have pre-defined list of perf events.
658 * We will generate and add attrs dynamically in probe() after we read HW
659 * configuration.
660 */
661static struct attribute_group arc_pmu_events_attr_gr = {
662	.name = "events",
663};
664
665static void arc_pmu_add_raw_event_attr(int j, char *str)
666{
667	memmove(arc_pmu->raw_entry[j].name, str, ARCPMU_EVENT_NAME_LEN - 1);
668	arc_pmu->attr[j].attr.attr.name = arc_pmu->raw_entry[j].name;
669	arc_pmu->attr[j].attr.attr.mode = VERIFY_OCTAL_PERMISSIONS(0444);
670	arc_pmu->attr[j].attr.show = arc_pmu_events_sysfs_show;
671	arc_pmu->attr[j].id = j;
672	arc_pmu->attrs[j] = &(arc_pmu->attr[j].attr.attr);
673}
674
675static int arc_pmu_raw_alloc(struct device *dev)
676{
677	arc_pmu->attr = devm_kmalloc_array(dev, arc_pmu->n_events + 1,
678		sizeof(*arc_pmu->attr), GFP_KERNEL | __GFP_ZERO);
679	if (!arc_pmu->attr)
680		return -ENOMEM;
681
682	arc_pmu->attrs = devm_kmalloc_array(dev, arc_pmu->n_events + 1,
683		sizeof(*arc_pmu->attrs), GFP_KERNEL | __GFP_ZERO);
684	if (!arc_pmu->attrs)
685		return -ENOMEM;
686
687	arc_pmu->raw_entry = devm_kmalloc_array(dev, arc_pmu->n_events,
688		sizeof(*arc_pmu->raw_entry), GFP_KERNEL | __GFP_ZERO);
689	if (!arc_pmu->raw_entry)
690		return -ENOMEM;
691
692	return 0;
693}
694
695static inline bool event_in_hw_event_map(int i, char *name)
696{
697	if (!arc_pmu_ev_hw_map[i])
698		return false;
699
700	if (!strlen(arc_pmu_ev_hw_map[i]))
701		return false;
702
703	if (strcmp(arc_pmu_ev_hw_map[i], name))
704		return false;
705
706	return true;
707}
708
709static void arc_pmu_map_hw_event(int j, char *str)
710{
711	int i;
712
713	/* See if HW condition has been mapped to a perf event_id */
714	for (i = 0; i < ARRAY_SIZE(arc_pmu_ev_hw_map); i++) {
715		if (event_in_hw_event_map(i, str)) {
716			pr_debug("mapping perf event %2d to h/w event \'%8s\' (idx %d)\n",
717				 i, str, j);
718			arc_pmu->ev_hw_idx[i] = j;
719		}
720	}
721}
722
723static int arc_pmu_device_probe(struct platform_device *pdev)
724{
725	struct arc_reg_pct_build pct_bcr;
726	struct arc_reg_cc_build cc_bcr;
727	int i, has_interrupts, irq = -1;
728	int counter_size;	/* in bits */
729
730	union cc_name {
731		struct {
732			u32 word0, word1;
733			char sentinel;
734		} indiv;
735		char str[ARCPMU_EVENT_NAME_LEN];
736	} cc_name;
737
738
739	READ_BCR(ARC_REG_PCT_BUILD, pct_bcr);
740	if (!pct_bcr.v) {
741		pr_err("This core does not have performance counters!\n");
742		return -ENODEV;
743	}
744	BUILD_BUG_ON(ARC_PERF_MAX_COUNTERS > 32);
745	if (WARN_ON(pct_bcr.c > ARC_PERF_MAX_COUNTERS))
746		return -EINVAL;
747
748	READ_BCR(ARC_REG_CC_BUILD, cc_bcr);
749	if (WARN(!cc_bcr.v, "Counters exist but No countable conditions?"))
750		return -EINVAL;
751
752	arc_pmu = devm_kzalloc(&pdev->dev, sizeof(struct arc_pmu), GFP_KERNEL);
753	if (!arc_pmu)
754		return -ENOMEM;
755
756	arc_pmu->n_events = cc_bcr.c;
757
758	if (arc_pmu_raw_alloc(&pdev->dev))
759		return -ENOMEM;
760
761	has_interrupts = is_isa_arcv2() ? pct_bcr.i : 0;
762
763	arc_pmu->n_counters = pct_bcr.c;
764	counter_size = 32 + (pct_bcr.s << 4);
765
766	arc_pmu->max_period = (1ULL << counter_size) / 2 - 1ULL;
767
768	pr_info("ARC perf\t: %d counters (%d bits), %d conditions%s\n",
769		arc_pmu->n_counters, counter_size, cc_bcr.c,
770		has_interrupts ? ", [overflow IRQ support]" : "");
771
772	cc_name.str[ARCPMU_EVENT_NAME_LEN - 1] = 0;
773	for (i = 0; i < PERF_COUNT_ARC_HW_MAX; i++)
774		arc_pmu->ev_hw_idx[i] = -1;
775
776	/* loop thru all available h/w condition indexes */
777	for (i = 0; i < cc_bcr.c; i++) {
778		write_aux_reg(ARC_REG_CC_INDEX, i);
779		cc_name.indiv.word0 = le32_to_cpu(read_aux_reg(ARC_REG_CC_NAME0));
780		cc_name.indiv.word1 = le32_to_cpu(read_aux_reg(ARC_REG_CC_NAME1));
781
782		arc_pmu_map_hw_event(i, cc_name.str);
783		arc_pmu_add_raw_event_attr(i, cc_name.str);
784	}
785
786	arc_pmu_events_attr_gr.attrs = arc_pmu->attrs;
787	arc_pmu->attr_groups[ARCPMU_ATTR_GR_EVENTS] = &arc_pmu_events_attr_gr;
788	arc_pmu->attr_groups[ARCPMU_ATTR_GR_FORMATS] = &arc_pmu_format_attr_gr;
789
790	arc_pmu->pmu = (struct pmu) {
791		.pmu_enable	= arc_pmu_enable,
792		.pmu_disable	= arc_pmu_disable,
793		.event_init	= arc_pmu_event_init,
794		.add		= arc_pmu_add,
795		.del		= arc_pmu_del,
796		.start		= arc_pmu_start,
797		.stop		= arc_pmu_stop,
798		.read		= arc_pmu_read,
799		.attr_groups	= arc_pmu->attr_groups,
800	};
801
802	if (has_interrupts) {
803		irq = platform_get_irq(pdev, 0);
804		if (irq >= 0) {
805			int ret;
806
807			arc_pmu->irq = irq;
808
809			/* intc map function ensures irq_set_percpu_devid() called */
810			ret = request_percpu_irq(irq, arc_pmu_intr, "ARC perf counters",
811						 this_cpu_ptr(&arc_pmu_cpu));
812
813			if (!ret)
814				on_each_cpu(arc_cpu_pmu_irq_init, &irq, 1);
815			else
816				irq = -1;
817		}
818
819	}
820
821	if (irq == -1)
822		arc_pmu->pmu.capabilities |= PERF_PMU_CAP_NO_INTERRUPT;
823
824	/*
825	 * perf parser doesn't really like '-' symbol in events name, so let's
826	 * use '_' in arc pct name as it goes to kernel PMU event prefix.
827	 */
828	return perf_pmu_register(&arc_pmu->pmu, "arc_pct", PERF_TYPE_RAW);
829}
830
831static const struct of_device_id arc_pmu_match[] = {
832	{ .compatible = "snps,arc700-pct" },
833	{ .compatible = "snps,archs-pct" },
834	{},
835};
836MODULE_DEVICE_TABLE(of, arc_pmu_match);
837
838static struct platform_driver arc_pmu_driver = {
839	.driver	= {
840		.name		= "arc-pct",
841		.of_match_table = of_match_ptr(arc_pmu_match),
842	},
843	.probe		= arc_pmu_device_probe,
844};
845
846module_platform_driver(arc_pmu_driver);
847
848MODULE_LICENSE("GPL");
849MODULE_AUTHOR("Mischa Jonker <mjonker@synopsys.com>");
850MODULE_DESCRIPTION("ARC PMU driver");
851