1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * HiSilicon SoC Hardware event counters support
4  *
5  * Copyright (C) 2017 HiSilicon Limited
6  * Author: Anurup M <anurup.m@huawei.com>
7  *         Shaokun Zhang <zhangshaokun@hisilicon.com>
8  *
9  * This code is based on the uncore PMUs like arm-cci and arm-ccn.
10  */
11 #include <linux/bitmap.h>
12 #include <linux/bitops.h>
13 #include <linux/bug.h>
14 #include <linux/err.h>
15 #include <linux/errno.h>
16 #include <linux/interrupt.h>
17 
18 #include <asm/cputype.h>
19 #include <asm/local64.h>
20 
21 #include "hisi_uncore_pmu.h"
22 
23 #define HISI_GET_EVENTID(ev) (ev->hw.config_base & 0xff)
24 #define HISI_MAX_PERIOD(nr) (GENMASK_ULL((nr) - 1, 0))
25 
26 /*
27  * PMU format attributes
28  */
29 ssize_t hisi_format_sysfs_show(struct device *dev,
30 			       struct device_attribute *attr, char *buf)
31 {
32 	struct dev_ext_attribute *eattr;
33 
34 	eattr = container_of(attr, struct dev_ext_attribute, attr);
35 
36 	return sysfs_emit(buf, "%s\n", (char *)eattr->var);
37 }
38 EXPORT_SYMBOL_GPL(hisi_format_sysfs_show);
39 
40 /*
41  * PMU event attributes
42  */
43 ssize_t hisi_event_sysfs_show(struct device *dev,
44 			      struct device_attribute *attr, char *page)
45 {
46 	struct dev_ext_attribute *eattr;
47 
48 	eattr = container_of(attr, struct dev_ext_attribute, attr);
49 
50 	return sysfs_emit(page, "config=0x%lx\n", (unsigned long)eattr->var);
51 }
52 EXPORT_SYMBOL_GPL(hisi_event_sysfs_show);
53 
54 /*
55  * sysfs cpumask attributes. For uncore PMU, we only have a single CPU to show
56  */
57 ssize_t hisi_cpumask_sysfs_show(struct device *dev,
58 				struct device_attribute *attr, char *buf)
59 {
60 	struct hisi_pmu *hisi_pmu = to_hisi_pmu(dev_get_drvdata(dev));
61 
62 	return sysfs_emit(buf, "%d\n", hisi_pmu->on_cpu);
63 }
64 EXPORT_SYMBOL_GPL(hisi_cpumask_sysfs_show);
65 
66 static bool hisi_validate_event_group(struct perf_event *event)
67 {
68 	struct perf_event *sibling, *leader = event->group_leader;
69 	struct hisi_pmu *hisi_pmu = to_hisi_pmu(event->pmu);
70 	/* Include count for the event */
71 	int counters = 1;
72 
73 	if (!is_software_event(leader)) {
74 		/*
75 		 * We must NOT create groups containing mixed PMUs, although
76 		 * software events are acceptable
77 		 */
78 		if (leader->pmu != event->pmu)
79 			return false;
80 
81 		/* Increment counter for the leader */
82 		if (leader != event)
83 			counters++;
84 	}
85 
86 	for_each_sibling_event(sibling, event->group_leader) {
87 		if (is_software_event(sibling))
88 			continue;
89 		if (sibling->pmu != event->pmu)
90 			return false;
91 		/* Increment counter for each sibling */
92 		counters++;
93 	}
94 
95 	/* The group can not count events more than the counters in the HW */
96 	return counters <= hisi_pmu->num_counters;
97 }
98 
99 int hisi_uncore_pmu_get_event_idx(struct perf_event *event)
100 {
101 	struct hisi_pmu *hisi_pmu = to_hisi_pmu(event->pmu);
102 	unsigned long *used_mask = hisi_pmu->pmu_events.used_mask;
103 	u32 num_counters = hisi_pmu->num_counters;
104 	int idx;
105 
106 	idx = find_first_zero_bit(used_mask, num_counters);
107 	if (idx == num_counters)
108 		return -EAGAIN;
109 
110 	set_bit(idx, used_mask);
111 
112 	return idx;
113 }
114 EXPORT_SYMBOL_GPL(hisi_uncore_pmu_get_event_idx);
115 
116 ssize_t hisi_uncore_pmu_identifier_attr_show(struct device *dev,
117 					     struct device_attribute *attr,
118 					     char *page)
119 {
120 	struct hisi_pmu *hisi_pmu = to_hisi_pmu(dev_get_drvdata(dev));
121 
122 	return sysfs_emit(page, "0x%08x\n", hisi_pmu->identifier);
123 }
124 EXPORT_SYMBOL_GPL(hisi_uncore_pmu_identifier_attr_show);
125 
126 static void hisi_uncore_pmu_clear_event_idx(struct hisi_pmu *hisi_pmu, int idx)
127 {
128 	clear_bit(idx, hisi_pmu->pmu_events.used_mask);
129 }
130 
131 static irqreturn_t hisi_uncore_pmu_isr(int irq, void *data)
132 {
133 	struct hisi_pmu *hisi_pmu = data;
134 	struct perf_event *event;
135 	unsigned long overflown;
136 	int idx;
137 
138 	overflown = hisi_pmu->ops->get_int_status(hisi_pmu);
139 	if (!overflown)
140 		return IRQ_NONE;
141 
142 	/*
143 	 * Find the counter index which overflowed if the bit was set
144 	 * and handle it.
145 	 */
146 	for_each_set_bit(idx, &overflown, hisi_pmu->num_counters) {
147 		/* Write 1 to clear the IRQ status flag */
148 		hisi_pmu->ops->clear_int_status(hisi_pmu, idx);
149 		/* Get the corresponding event struct */
150 		event = hisi_pmu->pmu_events.hw_events[idx];
151 		if (!event)
152 			continue;
153 
154 		hisi_uncore_pmu_event_update(event);
155 		hisi_uncore_pmu_set_event_period(event);
156 	}
157 
158 	return IRQ_HANDLED;
159 }
160 
161 int hisi_uncore_pmu_init_irq(struct hisi_pmu *hisi_pmu,
162 			     struct platform_device *pdev)
163 {
164 	int irq, ret;
165 
166 	irq = platform_get_irq(pdev, 0);
167 	if (irq < 0)
168 		return irq;
169 
170 	ret = devm_request_irq(&pdev->dev, irq, hisi_uncore_pmu_isr,
171 			       IRQF_NOBALANCING | IRQF_NO_THREAD,
172 			       dev_name(&pdev->dev), hisi_pmu);
173 	if (ret < 0) {
174 		dev_err(&pdev->dev,
175 			"Fail to request IRQ: %d ret: %d.\n", irq, ret);
176 		return ret;
177 	}
178 
179 	hisi_pmu->irq = irq;
180 
181 	return 0;
182 }
183 EXPORT_SYMBOL_GPL(hisi_uncore_pmu_init_irq);
184 
185 int hisi_uncore_pmu_event_init(struct perf_event *event)
186 {
187 	struct hw_perf_event *hwc = &event->hw;
188 	struct hisi_pmu *hisi_pmu;
189 
190 	if (event->attr.type != event->pmu->type)
191 		return -ENOENT;
192 
193 	/*
194 	 * We do not support sampling as the counters are all
195 	 * shared by all CPU cores in a CPU die(SCCL). Also we
196 	 * do not support attach to a task(per-process mode)
197 	 */
198 	if (is_sampling_event(event) || event->attach_state & PERF_ATTACH_TASK)
199 		return -EOPNOTSUPP;
200 
201 	/*
202 	 *  The uncore counters not specific to any CPU, so cannot
203 	 *  support per-task
204 	 */
205 	if (event->cpu < 0)
206 		return -EINVAL;
207 
208 	/*
209 	 * Validate if the events in group does not exceed the
210 	 * available counters in hardware.
211 	 */
212 	if (!hisi_validate_event_group(event))
213 		return -EINVAL;
214 
215 	hisi_pmu = to_hisi_pmu(event->pmu);
216 	if (event->attr.config > hisi_pmu->check_event)
217 		return -EINVAL;
218 
219 	if (hisi_pmu->on_cpu == -1)
220 		return -EINVAL;
221 	/*
222 	 * We don't assign an index until we actually place the event onto
223 	 * hardware. Use -1 to signify that we haven't decided where to put it
224 	 * yet.
225 	 */
226 	hwc->idx		= -1;
227 	hwc->config_base	= event->attr.config;
228 
229 	/* Enforce to use the same CPU for all events in this PMU */
230 	event->cpu = hisi_pmu->on_cpu;
231 
232 	return 0;
233 }
234 EXPORT_SYMBOL_GPL(hisi_uncore_pmu_event_init);
235 
236 /*
237  * Set the counter to count the event that we're interested in,
238  * and enable interrupt and counter.
239  */
240 static void hisi_uncore_pmu_enable_event(struct perf_event *event)
241 {
242 	struct hisi_pmu *hisi_pmu = to_hisi_pmu(event->pmu);
243 	struct hw_perf_event *hwc = &event->hw;
244 
245 	hisi_pmu->ops->write_evtype(hisi_pmu, hwc->idx,
246 				    HISI_GET_EVENTID(event));
247 
248 	if (hisi_pmu->ops->enable_filter)
249 		hisi_pmu->ops->enable_filter(event);
250 
251 	hisi_pmu->ops->enable_counter_int(hisi_pmu, hwc);
252 	hisi_pmu->ops->enable_counter(hisi_pmu, hwc);
253 }
254 
255 /*
256  * Disable counter and interrupt.
257  */
258 static void hisi_uncore_pmu_disable_event(struct perf_event *event)
259 {
260 	struct hisi_pmu *hisi_pmu = to_hisi_pmu(event->pmu);
261 	struct hw_perf_event *hwc = &event->hw;
262 
263 	hisi_pmu->ops->disable_counter(hisi_pmu, hwc);
264 	hisi_pmu->ops->disable_counter_int(hisi_pmu, hwc);
265 
266 	if (hisi_pmu->ops->disable_filter)
267 		hisi_pmu->ops->disable_filter(event);
268 }
269 
270 void hisi_uncore_pmu_set_event_period(struct perf_event *event)
271 {
272 	struct hisi_pmu *hisi_pmu = to_hisi_pmu(event->pmu);
273 	struct hw_perf_event *hwc = &event->hw;
274 
275 	/*
276 	 * The HiSilicon PMU counters support 32 bits or 48 bits, depending on
277 	 * the PMU. We reduce it to 2^(counter_bits - 1) to account for the
278 	 * extreme interrupt latency. So we could hopefully handle the overflow
279 	 * interrupt before another 2^(counter_bits - 1) events occur and the
280 	 * counter overtakes its previous value.
281 	 */
282 	u64 val = BIT_ULL(hisi_pmu->counter_bits - 1);
283 
284 	local64_set(&hwc->prev_count, val);
285 	/* Write start value to the hardware event counter */
286 	hisi_pmu->ops->write_counter(hisi_pmu, hwc, val);
287 }
288 EXPORT_SYMBOL_GPL(hisi_uncore_pmu_set_event_period);
289 
290 void hisi_uncore_pmu_event_update(struct perf_event *event)
291 {
292 	struct hisi_pmu *hisi_pmu = to_hisi_pmu(event->pmu);
293 	struct hw_perf_event *hwc = &event->hw;
294 	u64 delta, prev_raw_count, new_raw_count;
295 
296 	do {
297 		/* Read the count from the counter register */
298 		new_raw_count = hisi_pmu->ops->read_counter(hisi_pmu, hwc);
299 		prev_raw_count = local64_read(&hwc->prev_count);
300 	} while (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
301 				 new_raw_count) != prev_raw_count);
302 	/*
303 	 * compute the delta
304 	 */
305 	delta = (new_raw_count - prev_raw_count) &
306 		HISI_MAX_PERIOD(hisi_pmu->counter_bits);
307 	local64_add(delta, &event->count);
308 }
309 EXPORT_SYMBOL_GPL(hisi_uncore_pmu_event_update);
310 
311 void hisi_uncore_pmu_start(struct perf_event *event, int flags)
312 {
313 	struct hisi_pmu *hisi_pmu = to_hisi_pmu(event->pmu);
314 	struct hw_perf_event *hwc = &event->hw;
315 
316 	if (WARN_ON_ONCE(!(hwc->state & PERF_HES_STOPPED)))
317 		return;
318 
319 	WARN_ON_ONCE(!(hwc->state & PERF_HES_UPTODATE));
320 	hwc->state = 0;
321 	hisi_uncore_pmu_set_event_period(event);
322 
323 	if (flags & PERF_EF_RELOAD) {
324 		u64 prev_raw_count =  local64_read(&hwc->prev_count);
325 
326 		hisi_pmu->ops->write_counter(hisi_pmu, hwc, prev_raw_count);
327 	}
328 
329 	hisi_uncore_pmu_enable_event(event);
330 	perf_event_update_userpage(event);
331 }
332 EXPORT_SYMBOL_GPL(hisi_uncore_pmu_start);
333 
334 void hisi_uncore_pmu_stop(struct perf_event *event, int flags)
335 {
336 	struct hw_perf_event *hwc = &event->hw;
337 
338 	hisi_uncore_pmu_disable_event(event);
339 	WARN_ON_ONCE(hwc->state & PERF_HES_STOPPED);
340 	hwc->state |= PERF_HES_STOPPED;
341 
342 	if (hwc->state & PERF_HES_UPTODATE)
343 		return;
344 
345 	/* Read hardware counter and update the perf counter statistics */
346 	hisi_uncore_pmu_event_update(event);
347 	hwc->state |= PERF_HES_UPTODATE;
348 }
349 EXPORT_SYMBOL_GPL(hisi_uncore_pmu_stop);
350 
351 int hisi_uncore_pmu_add(struct perf_event *event, int flags)
352 {
353 	struct hisi_pmu *hisi_pmu = to_hisi_pmu(event->pmu);
354 	struct hw_perf_event *hwc = &event->hw;
355 	int idx;
356 
357 	hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
358 
359 	/* Get an available counter index for counting */
360 	idx = hisi_pmu->ops->get_event_idx(event);
361 	if (idx < 0)
362 		return idx;
363 
364 	event->hw.idx = idx;
365 	hisi_pmu->pmu_events.hw_events[idx] = event;
366 
367 	if (flags & PERF_EF_START)
368 		hisi_uncore_pmu_start(event, PERF_EF_RELOAD);
369 
370 	return 0;
371 }
372 EXPORT_SYMBOL_GPL(hisi_uncore_pmu_add);
373 
374 void hisi_uncore_pmu_del(struct perf_event *event, int flags)
375 {
376 	struct hisi_pmu *hisi_pmu = to_hisi_pmu(event->pmu);
377 	struct hw_perf_event *hwc = &event->hw;
378 
379 	hisi_uncore_pmu_stop(event, PERF_EF_UPDATE);
380 	hisi_uncore_pmu_clear_event_idx(hisi_pmu, hwc->idx);
381 	perf_event_update_userpage(event);
382 	hisi_pmu->pmu_events.hw_events[hwc->idx] = NULL;
383 }
384 EXPORT_SYMBOL_GPL(hisi_uncore_pmu_del);
385 
386 void hisi_uncore_pmu_read(struct perf_event *event)
387 {
388 	/* Read hardware counter and update the perf counter statistics */
389 	hisi_uncore_pmu_event_update(event);
390 }
391 EXPORT_SYMBOL_GPL(hisi_uncore_pmu_read);
392 
393 void hisi_uncore_pmu_enable(struct pmu *pmu)
394 {
395 	struct hisi_pmu *hisi_pmu = to_hisi_pmu(pmu);
396 	bool enabled = !bitmap_empty(hisi_pmu->pmu_events.used_mask,
397 				    hisi_pmu->num_counters);
398 
399 	if (!enabled)
400 		return;
401 
402 	hisi_pmu->ops->start_counters(hisi_pmu);
403 }
404 EXPORT_SYMBOL_GPL(hisi_uncore_pmu_enable);
405 
406 void hisi_uncore_pmu_disable(struct pmu *pmu)
407 {
408 	struct hisi_pmu *hisi_pmu = to_hisi_pmu(pmu);
409 
410 	hisi_pmu->ops->stop_counters(hisi_pmu);
411 }
412 EXPORT_SYMBOL_GPL(hisi_uncore_pmu_disable);
413 
414 
415 /*
416  * The Super CPU Cluster (SCCL) and CPU Cluster (CCL) IDs can be
417  * determined from the MPIDR_EL1, but the encoding varies by CPU:
418  *
419  * - For MT variants of TSV110:
420  *   SCCL is Aff2[7:3], CCL is Aff2[2:0]
421  *
422  * - For other MT parts:
423  *   SCCL is Aff3[7:0], CCL is Aff2[7:0]
424  *
425  * - For non-MT parts:
426  *   SCCL is Aff2[7:0], CCL is Aff1[7:0]
427  */
428 static void hisi_read_sccl_and_ccl_id(int *scclp, int *cclp)
429 {
430 	u64 mpidr = read_cpuid_mpidr();
431 	int aff3 = MPIDR_AFFINITY_LEVEL(mpidr, 3);
432 	int aff2 = MPIDR_AFFINITY_LEVEL(mpidr, 2);
433 	int aff1 = MPIDR_AFFINITY_LEVEL(mpidr, 1);
434 	bool mt = mpidr & MPIDR_MT_BITMASK;
435 	int sccl, ccl;
436 
437 	if (mt && read_cpuid_part_number() == HISI_CPU_PART_TSV110) {
438 		sccl = aff2 >> 3;
439 		ccl = aff2 & 0x7;
440 	} else if (mt) {
441 		sccl = aff3;
442 		ccl = aff2;
443 	} else {
444 		sccl = aff2;
445 		ccl = aff1;
446 	}
447 
448 	if (scclp)
449 		*scclp = sccl;
450 	if (cclp)
451 		*cclp = ccl;
452 }
453 
454 /*
455  * Check whether the CPU is associated with this uncore PMU
456  */
457 static bool hisi_pmu_cpu_is_associated_pmu(struct hisi_pmu *hisi_pmu)
458 {
459 	int sccl_id, ccl_id;
460 
461 	if (hisi_pmu->ccl_id == -1) {
462 		/* If CCL_ID is -1, the PMU only shares the same SCCL */
463 		hisi_read_sccl_and_ccl_id(&sccl_id, NULL);
464 
465 		return sccl_id == hisi_pmu->sccl_id;
466 	}
467 
468 	hisi_read_sccl_and_ccl_id(&sccl_id, &ccl_id);
469 
470 	return sccl_id == hisi_pmu->sccl_id && ccl_id == hisi_pmu->ccl_id;
471 }
472 
473 int hisi_uncore_pmu_online_cpu(unsigned int cpu, struct hlist_node *node)
474 {
475 	struct hisi_pmu *hisi_pmu = hlist_entry_safe(node, struct hisi_pmu,
476 						     node);
477 
478 	if (!hisi_pmu_cpu_is_associated_pmu(hisi_pmu))
479 		return 0;
480 
481 	cpumask_set_cpu(cpu, &hisi_pmu->associated_cpus);
482 
483 	/* If another CPU is already managing this PMU, simply return. */
484 	if (hisi_pmu->on_cpu != -1)
485 		return 0;
486 
487 	/* Use this CPU in cpumask for event counting */
488 	hisi_pmu->on_cpu = cpu;
489 
490 	/* Overflow interrupt also should use the same CPU */
491 	WARN_ON(irq_set_affinity(hisi_pmu->irq, cpumask_of(cpu)));
492 
493 	return 0;
494 }
495 EXPORT_SYMBOL_GPL(hisi_uncore_pmu_online_cpu);
496 
497 int hisi_uncore_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
498 {
499 	struct hisi_pmu *hisi_pmu = hlist_entry_safe(node, struct hisi_pmu,
500 						     node);
501 	cpumask_t pmu_online_cpus;
502 	unsigned int target;
503 
504 	if (!cpumask_test_and_clear_cpu(cpu, &hisi_pmu->associated_cpus))
505 		return 0;
506 
507 	/* Nothing to do if this CPU doesn't own the PMU */
508 	if (hisi_pmu->on_cpu != cpu)
509 		return 0;
510 
511 	/* Give up ownership of the PMU */
512 	hisi_pmu->on_cpu = -1;
513 
514 	/* Choose a new CPU to migrate ownership of the PMU to */
515 	cpumask_and(&pmu_online_cpus, &hisi_pmu->associated_cpus,
516 		    cpu_online_mask);
517 	target = cpumask_any_but(&pmu_online_cpus, cpu);
518 	if (target >= nr_cpu_ids)
519 		return 0;
520 
521 	perf_pmu_migrate_context(&hisi_pmu->pmu, cpu, target);
522 	/* Use this CPU for event counting */
523 	hisi_pmu->on_cpu = target;
524 	WARN_ON(irq_set_affinity(hisi_pmu->irq, cpumask_of(target)));
525 
526 	return 0;
527 }
528 EXPORT_SYMBOL_GPL(hisi_uncore_pmu_offline_cpu);
529 
530 MODULE_LICENSE("GPL v2");
531