xref: /openbmc/linux/drivers/perf/arm_smmuv3_pmu.c (revision 84b102f5)
1 // SPDX-License-Identifier: GPL-2.0
2 
3 /*
4  * This driver adds support for perf events to use the Performance
5  * Monitor Counter Groups (PMCG) associated with an SMMUv3 node
6  * to monitor that node.
7  *
8  * SMMUv3 PMCG devices are named as smmuv3_pmcg_<phys_addr_page> where
9  * <phys_addr_page> is the physical page address of the SMMU PMCG wrapped
10  * to 4K boundary. For example, the PMCG at 0xff88840000 is named
11  * smmuv3_pmcg_ff88840
12  *
13  * Filtering by stream id is done by specifying filtering parameters
14  * with the event. options are:
15  *   filter_enable    - 0 = no filtering, 1 = filtering enabled
16  *   filter_span      - 0 = exact match, 1 = pattern match
17  *   filter_stream_id - pattern to filter against
18  *
19  * To match a partial StreamID where the X most-significant bits must match
20  * but the Y least-significant bits might differ, STREAMID is programmed
21  * with a value that contains:
22  *  STREAMID[Y - 1] == 0.
23  *  STREAMID[Y - 2:0] == 1 (where Y > 1).
24  * The remainder of implemented bits of STREAMID (X bits, from bit Y upwards)
25  * contain a value to match from the corresponding bits of event StreamID.
26  *
27  * Example: perf stat -e smmuv3_pmcg_ff88840/transaction,filter_enable=1,
28  *                    filter_span=1,filter_stream_id=0x42/ -a netperf
29  * Applies filter pattern 0x42 to transaction events, which means events
30  * matching stream ids 0x42 and 0x43 are counted. Further filtering
31  * information is available in the SMMU documentation.
32  *
33  * SMMU events are not attributable to a CPU, so task mode and sampling
34  * are not supported.
35  */
36 
37 #include <linux/acpi.h>
38 #include <linux/acpi_iort.h>
39 #include <linux/bitfield.h>
40 #include <linux/bitops.h>
41 #include <linux/cpuhotplug.h>
42 #include <linux/cpumask.h>
43 #include <linux/device.h>
44 #include <linux/errno.h>
45 #include <linux/interrupt.h>
46 #include <linux/irq.h>
47 #include <linux/kernel.h>
48 #include <linux/list.h>
49 #include <linux/msi.h>
50 #include <linux/perf_event.h>
51 #include <linux/platform_device.h>
52 #include <linux/smp.h>
53 #include <linux/sysfs.h>
54 #include <linux/types.h>
55 
56 #define SMMU_PMCG_EVCNTR0               0x0
57 #define SMMU_PMCG_EVCNTR(n, stride)     (SMMU_PMCG_EVCNTR0 + (n) * (stride))
58 #define SMMU_PMCG_EVTYPER0              0x400
59 #define SMMU_PMCG_EVTYPER(n)            (SMMU_PMCG_EVTYPER0 + (n) * 4)
60 #define SMMU_PMCG_SID_SPAN_SHIFT        29
61 #define SMMU_PMCG_SMR0                  0xA00
62 #define SMMU_PMCG_SMR(n)                (SMMU_PMCG_SMR0 + (n) * 4)
63 #define SMMU_PMCG_CNTENSET0             0xC00
64 #define SMMU_PMCG_CNTENCLR0             0xC20
65 #define SMMU_PMCG_INTENSET0             0xC40
66 #define SMMU_PMCG_INTENCLR0             0xC60
67 #define SMMU_PMCG_OVSCLR0               0xC80
68 #define SMMU_PMCG_OVSSET0               0xCC0
69 #define SMMU_PMCG_CFGR                  0xE00
70 #define SMMU_PMCG_CFGR_SID_FILTER_TYPE  BIT(23)
71 #define SMMU_PMCG_CFGR_MSI              BIT(21)
72 #define SMMU_PMCG_CFGR_RELOC_CTRS       BIT(20)
73 #define SMMU_PMCG_CFGR_SIZE             GENMASK(13, 8)
74 #define SMMU_PMCG_CFGR_NCTR             GENMASK(5, 0)
75 #define SMMU_PMCG_CR                    0xE04
76 #define SMMU_PMCG_CR_ENABLE             BIT(0)
77 #define SMMU_PMCG_IIDR                  0xE08
78 #define SMMU_PMCG_CEID0                 0xE20
79 #define SMMU_PMCG_CEID1                 0xE28
80 #define SMMU_PMCG_IRQ_CTRL              0xE50
81 #define SMMU_PMCG_IRQ_CTRL_IRQEN        BIT(0)
82 #define SMMU_PMCG_IRQ_CFG0              0xE58
83 #define SMMU_PMCG_IRQ_CFG1              0xE60
84 #define SMMU_PMCG_IRQ_CFG2              0xE64
85 
86 /* MSI config fields */
87 #define MSI_CFG0_ADDR_MASK              GENMASK_ULL(51, 2)
88 #define MSI_CFG2_MEMATTR_DEVICE_nGnRE   0x1
89 
90 #define SMMU_PMCG_DEFAULT_FILTER_SPAN   1
91 #define SMMU_PMCG_DEFAULT_FILTER_SID    GENMASK(31, 0)
92 
93 #define SMMU_PMCG_MAX_COUNTERS          64
94 #define SMMU_PMCG_ARCH_MAX_EVENTS       128
95 
96 #define SMMU_PMCG_PA_SHIFT              12
97 
98 #define SMMU_PMCG_EVCNTR_RDONLY         BIT(0)
99 
100 static int cpuhp_state_num;
101 
102 struct smmu_pmu {
103 	struct hlist_node node;
104 	struct perf_event *events[SMMU_PMCG_MAX_COUNTERS];
105 	DECLARE_BITMAP(used_counters, SMMU_PMCG_MAX_COUNTERS);
106 	DECLARE_BITMAP(supported_events, SMMU_PMCG_ARCH_MAX_EVENTS);
107 	unsigned int irq;
108 	unsigned int on_cpu;
109 	struct pmu pmu;
110 	unsigned int num_counters;
111 	struct device *dev;
112 	void __iomem *reg_base;
113 	void __iomem *reloc_base;
114 	u64 counter_mask;
115 	u32 options;
116 	u32 iidr;
117 	bool global_filter;
118 };
119 
120 #define to_smmu_pmu(p) (container_of(p, struct smmu_pmu, pmu))
121 
122 #define SMMU_PMU_EVENT_ATTR_EXTRACTOR(_name, _config, _start, _end)        \
123 	static inline u32 get_##_name(struct perf_event *event)            \
124 	{                                                                  \
125 		return FIELD_GET(GENMASK_ULL(_end, _start),                \
126 				 event->attr._config);                     \
127 	}                                                                  \
128 
129 SMMU_PMU_EVENT_ATTR_EXTRACTOR(event, config, 0, 15);
130 SMMU_PMU_EVENT_ATTR_EXTRACTOR(filter_stream_id, config1, 0, 31);
131 SMMU_PMU_EVENT_ATTR_EXTRACTOR(filter_span, config1, 32, 32);
132 SMMU_PMU_EVENT_ATTR_EXTRACTOR(filter_enable, config1, 33, 33);
133 
134 static inline void smmu_pmu_enable(struct pmu *pmu)
135 {
136 	struct smmu_pmu *smmu_pmu = to_smmu_pmu(pmu);
137 
138 	writel(SMMU_PMCG_IRQ_CTRL_IRQEN,
139 	       smmu_pmu->reg_base + SMMU_PMCG_IRQ_CTRL);
140 	writel(SMMU_PMCG_CR_ENABLE, smmu_pmu->reg_base + SMMU_PMCG_CR);
141 }
142 
143 static inline void smmu_pmu_disable(struct pmu *pmu)
144 {
145 	struct smmu_pmu *smmu_pmu = to_smmu_pmu(pmu);
146 
147 	writel(0, smmu_pmu->reg_base + SMMU_PMCG_CR);
148 	writel(0, smmu_pmu->reg_base + SMMU_PMCG_IRQ_CTRL);
149 }
150 
151 static inline void smmu_pmu_counter_set_value(struct smmu_pmu *smmu_pmu,
152 					      u32 idx, u64 value)
153 {
154 	if (smmu_pmu->counter_mask & BIT(32))
155 		writeq(value, smmu_pmu->reloc_base + SMMU_PMCG_EVCNTR(idx, 8));
156 	else
157 		writel(value, smmu_pmu->reloc_base + SMMU_PMCG_EVCNTR(idx, 4));
158 }
159 
160 static inline u64 smmu_pmu_counter_get_value(struct smmu_pmu *smmu_pmu, u32 idx)
161 {
162 	u64 value;
163 
164 	if (smmu_pmu->counter_mask & BIT(32))
165 		value = readq(smmu_pmu->reloc_base + SMMU_PMCG_EVCNTR(idx, 8));
166 	else
167 		value = readl(smmu_pmu->reloc_base + SMMU_PMCG_EVCNTR(idx, 4));
168 
169 	return value;
170 }
171 
172 static inline void smmu_pmu_counter_enable(struct smmu_pmu *smmu_pmu, u32 idx)
173 {
174 	writeq(BIT(idx), smmu_pmu->reg_base + SMMU_PMCG_CNTENSET0);
175 }
176 
177 static inline void smmu_pmu_counter_disable(struct smmu_pmu *smmu_pmu, u32 idx)
178 {
179 	writeq(BIT(idx), smmu_pmu->reg_base + SMMU_PMCG_CNTENCLR0);
180 }
181 
182 static inline void smmu_pmu_interrupt_enable(struct smmu_pmu *smmu_pmu, u32 idx)
183 {
184 	writeq(BIT(idx), smmu_pmu->reg_base + SMMU_PMCG_INTENSET0);
185 }
186 
187 static inline void smmu_pmu_interrupt_disable(struct smmu_pmu *smmu_pmu,
188 					      u32 idx)
189 {
190 	writeq(BIT(idx), smmu_pmu->reg_base + SMMU_PMCG_INTENCLR0);
191 }
192 
193 static inline void smmu_pmu_set_evtyper(struct smmu_pmu *smmu_pmu, u32 idx,
194 					u32 val)
195 {
196 	writel(val, smmu_pmu->reg_base + SMMU_PMCG_EVTYPER(idx));
197 }
198 
199 static inline void smmu_pmu_set_smr(struct smmu_pmu *smmu_pmu, u32 idx, u32 val)
200 {
201 	writel(val, smmu_pmu->reg_base + SMMU_PMCG_SMR(idx));
202 }
203 
204 static void smmu_pmu_event_update(struct perf_event *event)
205 {
206 	struct hw_perf_event *hwc = &event->hw;
207 	struct smmu_pmu *smmu_pmu = to_smmu_pmu(event->pmu);
208 	u64 delta, prev, now;
209 	u32 idx = hwc->idx;
210 
211 	do {
212 		prev = local64_read(&hwc->prev_count);
213 		now = smmu_pmu_counter_get_value(smmu_pmu, idx);
214 	} while (local64_cmpxchg(&hwc->prev_count, prev, now) != prev);
215 
216 	/* handle overflow. */
217 	delta = now - prev;
218 	delta &= smmu_pmu->counter_mask;
219 
220 	local64_add(delta, &event->count);
221 }
222 
223 static void smmu_pmu_set_period(struct smmu_pmu *smmu_pmu,
224 				struct hw_perf_event *hwc)
225 {
226 	u32 idx = hwc->idx;
227 	u64 new;
228 
229 	if (smmu_pmu->options & SMMU_PMCG_EVCNTR_RDONLY) {
230 		/*
231 		 * On platforms that require this quirk, if the counter starts
232 		 * at < half_counter value and wraps, the current logic of
233 		 * handling the overflow may not work. It is expected that,
234 		 * those platforms will have full 64 counter bits implemented
235 		 * so that such a possibility is remote(eg: HiSilicon HIP08).
236 		 */
237 		new = smmu_pmu_counter_get_value(smmu_pmu, idx);
238 	} else {
239 		/*
240 		 * We limit the max period to half the max counter value
241 		 * of the counter size, so that even in the case of extreme
242 		 * interrupt latency the counter will (hopefully) not wrap
243 		 * past its initial value.
244 		 */
245 		new = smmu_pmu->counter_mask >> 1;
246 		smmu_pmu_counter_set_value(smmu_pmu, idx, new);
247 	}
248 
249 	local64_set(&hwc->prev_count, new);
250 }
251 
252 static void smmu_pmu_set_event_filter(struct perf_event *event,
253 				      int idx, u32 span, u32 sid)
254 {
255 	struct smmu_pmu *smmu_pmu = to_smmu_pmu(event->pmu);
256 	u32 evtyper;
257 
258 	evtyper = get_event(event) | span << SMMU_PMCG_SID_SPAN_SHIFT;
259 	smmu_pmu_set_evtyper(smmu_pmu, idx, evtyper);
260 	smmu_pmu_set_smr(smmu_pmu, idx, sid);
261 }
262 
263 static bool smmu_pmu_check_global_filter(struct perf_event *curr,
264 					 struct perf_event *new)
265 {
266 	if (get_filter_enable(new) != get_filter_enable(curr))
267 		return false;
268 
269 	if (!get_filter_enable(new))
270 		return true;
271 
272 	return get_filter_span(new) == get_filter_span(curr) &&
273 	       get_filter_stream_id(new) == get_filter_stream_id(curr);
274 }
275 
276 static int smmu_pmu_apply_event_filter(struct smmu_pmu *smmu_pmu,
277 				       struct perf_event *event, int idx)
278 {
279 	u32 span, sid;
280 	unsigned int num_ctrs = smmu_pmu->num_counters;
281 	bool filter_en = !!get_filter_enable(event);
282 
283 	span = filter_en ? get_filter_span(event) :
284 			   SMMU_PMCG_DEFAULT_FILTER_SPAN;
285 	sid = filter_en ? get_filter_stream_id(event) :
286 			   SMMU_PMCG_DEFAULT_FILTER_SID;
287 
288 	/* Support individual filter settings */
289 	if (!smmu_pmu->global_filter) {
290 		smmu_pmu_set_event_filter(event, idx, span, sid);
291 		return 0;
292 	}
293 
294 	/* Requested settings same as current global settings*/
295 	idx = find_first_bit(smmu_pmu->used_counters, num_ctrs);
296 	if (idx == num_ctrs ||
297 	    smmu_pmu_check_global_filter(smmu_pmu->events[idx], event)) {
298 		smmu_pmu_set_event_filter(event, 0, span, sid);
299 		return 0;
300 	}
301 
302 	return -EAGAIN;
303 }
304 
305 static int smmu_pmu_get_event_idx(struct smmu_pmu *smmu_pmu,
306 				  struct perf_event *event)
307 {
308 	int idx, err;
309 	unsigned int num_ctrs = smmu_pmu->num_counters;
310 
311 	idx = find_first_zero_bit(smmu_pmu->used_counters, num_ctrs);
312 	if (idx == num_ctrs)
313 		/* The counters are all in use. */
314 		return -EAGAIN;
315 
316 	err = smmu_pmu_apply_event_filter(smmu_pmu, event, idx);
317 	if (err)
318 		return err;
319 
320 	set_bit(idx, smmu_pmu->used_counters);
321 
322 	return idx;
323 }
324 
325 static bool smmu_pmu_events_compatible(struct perf_event *curr,
326 				       struct perf_event *new)
327 {
328 	if (new->pmu != curr->pmu)
329 		return false;
330 
331 	if (to_smmu_pmu(new->pmu)->global_filter &&
332 	    !smmu_pmu_check_global_filter(curr, new))
333 		return false;
334 
335 	return true;
336 }
337 
338 /*
339  * Implementation of abstract pmu functionality required by
340  * the core perf events code.
341  */
342 
343 static int smmu_pmu_event_init(struct perf_event *event)
344 {
345 	struct hw_perf_event *hwc = &event->hw;
346 	struct smmu_pmu *smmu_pmu = to_smmu_pmu(event->pmu);
347 	struct device *dev = smmu_pmu->dev;
348 	struct perf_event *sibling;
349 	int group_num_events = 1;
350 	u16 event_id;
351 
352 	if (event->attr.type != event->pmu->type)
353 		return -ENOENT;
354 
355 	if (hwc->sample_period) {
356 		dev_dbg(dev, "Sampling not supported\n");
357 		return -EOPNOTSUPP;
358 	}
359 
360 	if (event->cpu < 0) {
361 		dev_dbg(dev, "Per-task mode not supported\n");
362 		return -EOPNOTSUPP;
363 	}
364 
365 	/* Verify specified event is supported on this PMU */
366 	event_id = get_event(event);
367 	if (event_id < SMMU_PMCG_ARCH_MAX_EVENTS &&
368 	    (!test_bit(event_id, smmu_pmu->supported_events))) {
369 		dev_dbg(dev, "Invalid event %d for this PMU\n", event_id);
370 		return -EINVAL;
371 	}
372 
373 	/* Don't allow groups with mixed PMUs, except for s/w events */
374 	if (!is_software_event(event->group_leader)) {
375 		if (!smmu_pmu_events_compatible(event->group_leader, event))
376 			return -EINVAL;
377 
378 		if (++group_num_events > smmu_pmu->num_counters)
379 			return -EINVAL;
380 	}
381 
382 	for_each_sibling_event(sibling, event->group_leader) {
383 		if (is_software_event(sibling))
384 			continue;
385 
386 		if (!smmu_pmu_events_compatible(sibling, event))
387 			return -EINVAL;
388 
389 		if (++group_num_events > smmu_pmu->num_counters)
390 			return -EINVAL;
391 	}
392 
393 	hwc->idx = -1;
394 
395 	/*
396 	 * Ensure all events are on the same cpu so all events are in the
397 	 * same cpu context, to avoid races on pmu_enable etc.
398 	 */
399 	event->cpu = smmu_pmu->on_cpu;
400 
401 	return 0;
402 }
403 
404 static void smmu_pmu_event_start(struct perf_event *event, int flags)
405 {
406 	struct smmu_pmu *smmu_pmu = to_smmu_pmu(event->pmu);
407 	struct hw_perf_event *hwc = &event->hw;
408 	int idx = hwc->idx;
409 
410 	hwc->state = 0;
411 
412 	smmu_pmu_set_period(smmu_pmu, hwc);
413 
414 	smmu_pmu_counter_enable(smmu_pmu, idx);
415 }
416 
417 static void smmu_pmu_event_stop(struct perf_event *event, int flags)
418 {
419 	struct smmu_pmu *smmu_pmu = to_smmu_pmu(event->pmu);
420 	struct hw_perf_event *hwc = &event->hw;
421 	int idx = hwc->idx;
422 
423 	if (hwc->state & PERF_HES_STOPPED)
424 		return;
425 
426 	smmu_pmu_counter_disable(smmu_pmu, idx);
427 	/* As the counter gets updated on _start, ignore PERF_EF_UPDATE */
428 	smmu_pmu_event_update(event);
429 	hwc->state |= PERF_HES_STOPPED | PERF_HES_UPTODATE;
430 }
431 
432 static int smmu_pmu_event_add(struct perf_event *event, int flags)
433 {
434 	struct hw_perf_event *hwc = &event->hw;
435 	int idx;
436 	struct smmu_pmu *smmu_pmu = to_smmu_pmu(event->pmu);
437 
438 	idx = smmu_pmu_get_event_idx(smmu_pmu, event);
439 	if (idx < 0)
440 		return idx;
441 
442 	hwc->idx = idx;
443 	hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
444 	smmu_pmu->events[idx] = event;
445 	local64_set(&hwc->prev_count, 0);
446 
447 	smmu_pmu_interrupt_enable(smmu_pmu, idx);
448 
449 	if (flags & PERF_EF_START)
450 		smmu_pmu_event_start(event, flags);
451 
452 	/* Propagate changes to the userspace mapping. */
453 	perf_event_update_userpage(event);
454 
455 	return 0;
456 }
457 
458 static void smmu_pmu_event_del(struct perf_event *event, int flags)
459 {
460 	struct hw_perf_event *hwc = &event->hw;
461 	struct smmu_pmu *smmu_pmu = to_smmu_pmu(event->pmu);
462 	int idx = hwc->idx;
463 
464 	smmu_pmu_event_stop(event, flags | PERF_EF_UPDATE);
465 	smmu_pmu_interrupt_disable(smmu_pmu, idx);
466 	smmu_pmu->events[idx] = NULL;
467 	clear_bit(idx, smmu_pmu->used_counters);
468 
469 	perf_event_update_userpage(event);
470 }
471 
472 static void smmu_pmu_event_read(struct perf_event *event)
473 {
474 	smmu_pmu_event_update(event);
475 }
476 
477 /* cpumask */
478 
479 static ssize_t smmu_pmu_cpumask_show(struct device *dev,
480 				     struct device_attribute *attr,
481 				     char *buf)
482 {
483 	struct smmu_pmu *smmu_pmu = to_smmu_pmu(dev_get_drvdata(dev));
484 
485 	return cpumap_print_to_pagebuf(true, buf, cpumask_of(smmu_pmu->on_cpu));
486 }
487 
488 static struct device_attribute smmu_pmu_cpumask_attr =
489 		__ATTR(cpumask, 0444, smmu_pmu_cpumask_show, NULL);
490 
491 static struct attribute *smmu_pmu_cpumask_attrs[] = {
492 	&smmu_pmu_cpumask_attr.attr,
493 	NULL
494 };
495 
496 static struct attribute_group smmu_pmu_cpumask_group = {
497 	.attrs = smmu_pmu_cpumask_attrs,
498 };
499 
500 /* Events */
501 
502 static ssize_t smmu_pmu_event_show(struct device *dev,
503 				   struct device_attribute *attr, char *page)
504 {
505 	struct perf_pmu_events_attr *pmu_attr;
506 
507 	pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr);
508 
509 	return sprintf(page, "event=0x%02llx\n", pmu_attr->id);
510 }
511 
512 #define SMMU_EVENT_ATTR(name, config) \
513 	PMU_EVENT_ATTR(name, smmu_event_attr_##name, \
514 		       config, smmu_pmu_event_show)
515 SMMU_EVENT_ATTR(cycles, 0);
516 SMMU_EVENT_ATTR(transaction, 1);
517 SMMU_EVENT_ATTR(tlb_miss, 2);
518 SMMU_EVENT_ATTR(config_cache_miss, 3);
519 SMMU_EVENT_ATTR(trans_table_walk_access, 4);
520 SMMU_EVENT_ATTR(config_struct_access, 5);
521 SMMU_EVENT_ATTR(pcie_ats_trans_rq, 6);
522 SMMU_EVENT_ATTR(pcie_ats_trans_passed, 7);
523 
524 static struct attribute *smmu_pmu_events[] = {
525 	&smmu_event_attr_cycles.attr.attr,
526 	&smmu_event_attr_transaction.attr.attr,
527 	&smmu_event_attr_tlb_miss.attr.attr,
528 	&smmu_event_attr_config_cache_miss.attr.attr,
529 	&smmu_event_attr_trans_table_walk_access.attr.attr,
530 	&smmu_event_attr_config_struct_access.attr.attr,
531 	&smmu_event_attr_pcie_ats_trans_rq.attr.attr,
532 	&smmu_event_attr_pcie_ats_trans_passed.attr.attr,
533 	NULL
534 };
535 
536 static umode_t smmu_pmu_event_is_visible(struct kobject *kobj,
537 					 struct attribute *attr, int unused)
538 {
539 	struct device *dev = kobj_to_dev(kobj);
540 	struct smmu_pmu *smmu_pmu = to_smmu_pmu(dev_get_drvdata(dev));
541 	struct perf_pmu_events_attr *pmu_attr;
542 
543 	pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr.attr);
544 
545 	if (test_bit(pmu_attr->id, smmu_pmu->supported_events))
546 		return attr->mode;
547 
548 	return 0;
549 }
550 
551 static struct attribute_group smmu_pmu_events_group = {
552 	.name = "events",
553 	.attrs = smmu_pmu_events,
554 	.is_visible = smmu_pmu_event_is_visible,
555 };
556 
557 static ssize_t smmu_pmu_identifier_attr_show(struct device *dev,
558 					struct device_attribute *attr,
559 					char *page)
560 {
561 	struct smmu_pmu *smmu_pmu = to_smmu_pmu(dev_get_drvdata(dev));
562 
563 	return snprintf(page, PAGE_SIZE, "0x%08x\n", smmu_pmu->iidr);
564 }
565 
566 static umode_t smmu_pmu_identifier_attr_visible(struct kobject *kobj,
567 						struct attribute *attr,
568 						int n)
569 {
570 	struct device *dev = kobj_to_dev(kobj);
571 	struct smmu_pmu *smmu_pmu = to_smmu_pmu(dev_get_drvdata(dev));
572 
573 	if (!smmu_pmu->iidr)
574 		return 0;
575 	return attr->mode;
576 }
577 
578 static struct device_attribute smmu_pmu_identifier_attr =
579 	__ATTR(identifier, 0444, smmu_pmu_identifier_attr_show, NULL);
580 
581 static struct attribute *smmu_pmu_identifier_attrs[] = {
582 	&smmu_pmu_identifier_attr.attr,
583 	NULL
584 };
585 
586 static struct attribute_group smmu_pmu_identifier_group = {
587 	.attrs = smmu_pmu_identifier_attrs,
588 	.is_visible = smmu_pmu_identifier_attr_visible,
589 };
590 
591 /* Formats */
592 PMU_FORMAT_ATTR(event,		   "config:0-15");
593 PMU_FORMAT_ATTR(filter_stream_id,  "config1:0-31");
594 PMU_FORMAT_ATTR(filter_span,	   "config1:32");
595 PMU_FORMAT_ATTR(filter_enable,	   "config1:33");
596 
597 static struct attribute *smmu_pmu_formats[] = {
598 	&format_attr_event.attr,
599 	&format_attr_filter_stream_id.attr,
600 	&format_attr_filter_span.attr,
601 	&format_attr_filter_enable.attr,
602 	NULL
603 };
604 
605 static struct attribute_group smmu_pmu_format_group = {
606 	.name = "format",
607 	.attrs = smmu_pmu_formats,
608 };
609 
610 static const struct attribute_group *smmu_pmu_attr_grps[] = {
611 	&smmu_pmu_cpumask_group,
612 	&smmu_pmu_events_group,
613 	&smmu_pmu_format_group,
614 	&smmu_pmu_identifier_group,
615 	NULL
616 };
617 
618 /*
619  * Generic device handlers
620  */
621 
622 static int smmu_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
623 {
624 	struct smmu_pmu *smmu_pmu;
625 	unsigned int target;
626 
627 	smmu_pmu = hlist_entry_safe(node, struct smmu_pmu, node);
628 	if (cpu != smmu_pmu->on_cpu)
629 		return 0;
630 
631 	target = cpumask_any_but(cpu_online_mask, cpu);
632 	if (target >= nr_cpu_ids)
633 		return 0;
634 
635 	perf_pmu_migrate_context(&smmu_pmu->pmu, cpu, target);
636 	smmu_pmu->on_cpu = target;
637 	WARN_ON(irq_set_affinity_hint(smmu_pmu->irq, cpumask_of(target)));
638 
639 	return 0;
640 }
641 
642 static irqreturn_t smmu_pmu_handle_irq(int irq_num, void *data)
643 {
644 	struct smmu_pmu *smmu_pmu = data;
645 	u64 ovsr;
646 	unsigned int idx;
647 
648 	ovsr = readq(smmu_pmu->reloc_base + SMMU_PMCG_OVSSET0);
649 	if (!ovsr)
650 		return IRQ_NONE;
651 
652 	writeq(ovsr, smmu_pmu->reloc_base + SMMU_PMCG_OVSCLR0);
653 
654 	for_each_set_bit(idx, (unsigned long *)&ovsr, smmu_pmu->num_counters) {
655 		struct perf_event *event = smmu_pmu->events[idx];
656 		struct hw_perf_event *hwc;
657 
658 		if (WARN_ON_ONCE(!event))
659 			continue;
660 
661 		smmu_pmu_event_update(event);
662 		hwc = &event->hw;
663 
664 		smmu_pmu_set_period(smmu_pmu, hwc);
665 	}
666 
667 	return IRQ_HANDLED;
668 }
669 
670 static void smmu_pmu_free_msis(void *data)
671 {
672 	struct device *dev = data;
673 
674 	platform_msi_domain_free_irqs(dev);
675 }
676 
677 static void smmu_pmu_write_msi_msg(struct msi_desc *desc, struct msi_msg *msg)
678 {
679 	phys_addr_t doorbell;
680 	struct device *dev = msi_desc_to_dev(desc);
681 	struct smmu_pmu *pmu = dev_get_drvdata(dev);
682 
683 	doorbell = (((u64)msg->address_hi) << 32) | msg->address_lo;
684 	doorbell &= MSI_CFG0_ADDR_MASK;
685 
686 	writeq_relaxed(doorbell, pmu->reg_base + SMMU_PMCG_IRQ_CFG0);
687 	writel_relaxed(msg->data, pmu->reg_base + SMMU_PMCG_IRQ_CFG1);
688 	writel_relaxed(MSI_CFG2_MEMATTR_DEVICE_nGnRE,
689 		       pmu->reg_base + SMMU_PMCG_IRQ_CFG2);
690 }
691 
692 static void smmu_pmu_setup_msi(struct smmu_pmu *pmu)
693 {
694 	struct msi_desc *desc;
695 	struct device *dev = pmu->dev;
696 	int ret;
697 
698 	/* Clear MSI address reg */
699 	writeq_relaxed(0, pmu->reg_base + SMMU_PMCG_IRQ_CFG0);
700 
701 	/* MSI supported or not */
702 	if (!(readl(pmu->reg_base + SMMU_PMCG_CFGR) & SMMU_PMCG_CFGR_MSI))
703 		return;
704 
705 	ret = platform_msi_domain_alloc_irqs(dev, 1, smmu_pmu_write_msi_msg);
706 	if (ret) {
707 		dev_warn(dev, "failed to allocate MSIs\n");
708 		return;
709 	}
710 
711 	desc = first_msi_entry(dev);
712 	if (desc)
713 		pmu->irq = desc->irq;
714 
715 	/* Add callback to free MSIs on teardown */
716 	devm_add_action(dev, smmu_pmu_free_msis, dev);
717 }
718 
719 static int smmu_pmu_setup_irq(struct smmu_pmu *pmu)
720 {
721 	unsigned long flags = IRQF_NOBALANCING | IRQF_SHARED | IRQF_NO_THREAD;
722 	int irq, ret = -ENXIO;
723 
724 	smmu_pmu_setup_msi(pmu);
725 
726 	irq = pmu->irq;
727 	if (irq)
728 		ret = devm_request_irq(pmu->dev, irq, smmu_pmu_handle_irq,
729 				       flags, "smmuv3-pmu", pmu);
730 	return ret;
731 }
732 
733 static void smmu_pmu_reset(struct smmu_pmu *smmu_pmu)
734 {
735 	u64 counter_present_mask = GENMASK_ULL(smmu_pmu->num_counters - 1, 0);
736 
737 	smmu_pmu_disable(&smmu_pmu->pmu);
738 
739 	/* Disable counter and interrupt */
740 	writeq_relaxed(counter_present_mask,
741 		       smmu_pmu->reg_base + SMMU_PMCG_CNTENCLR0);
742 	writeq_relaxed(counter_present_mask,
743 		       smmu_pmu->reg_base + SMMU_PMCG_INTENCLR0);
744 	writeq_relaxed(counter_present_mask,
745 		       smmu_pmu->reloc_base + SMMU_PMCG_OVSCLR0);
746 }
747 
748 static void smmu_pmu_get_acpi_options(struct smmu_pmu *smmu_pmu)
749 {
750 	u32 model;
751 
752 	model = *(u32 *)dev_get_platdata(smmu_pmu->dev);
753 
754 	switch (model) {
755 	case IORT_SMMU_V3_PMCG_HISI_HIP08:
756 		/* HiSilicon Erratum 162001800 */
757 		smmu_pmu->options |= SMMU_PMCG_EVCNTR_RDONLY;
758 		break;
759 	}
760 
761 	dev_notice(smmu_pmu->dev, "option mask 0x%x\n", smmu_pmu->options);
762 }
763 
764 static int smmu_pmu_probe(struct platform_device *pdev)
765 {
766 	struct smmu_pmu *smmu_pmu;
767 	struct resource *res_0;
768 	u32 cfgr, reg_size;
769 	u64 ceid_64[2];
770 	int irq, err;
771 	char *name;
772 	struct device *dev = &pdev->dev;
773 
774 	smmu_pmu = devm_kzalloc(dev, sizeof(*smmu_pmu), GFP_KERNEL);
775 	if (!smmu_pmu)
776 		return -ENOMEM;
777 
778 	smmu_pmu->dev = dev;
779 	platform_set_drvdata(pdev, smmu_pmu);
780 
781 	smmu_pmu->pmu = (struct pmu) {
782 		.module		= THIS_MODULE,
783 		.task_ctx_nr    = perf_invalid_context,
784 		.pmu_enable	= smmu_pmu_enable,
785 		.pmu_disable	= smmu_pmu_disable,
786 		.event_init	= smmu_pmu_event_init,
787 		.add		= smmu_pmu_event_add,
788 		.del		= smmu_pmu_event_del,
789 		.start		= smmu_pmu_event_start,
790 		.stop		= smmu_pmu_event_stop,
791 		.read		= smmu_pmu_event_read,
792 		.attr_groups	= smmu_pmu_attr_grps,
793 		.capabilities	= PERF_PMU_CAP_NO_EXCLUDE,
794 	};
795 
796 	smmu_pmu->reg_base = devm_platform_get_and_ioremap_resource(pdev, 0, &res_0);
797 	if (IS_ERR(smmu_pmu->reg_base))
798 		return PTR_ERR(smmu_pmu->reg_base);
799 
800 	cfgr = readl_relaxed(smmu_pmu->reg_base + SMMU_PMCG_CFGR);
801 
802 	/* Determine if page 1 is present */
803 	if (cfgr & SMMU_PMCG_CFGR_RELOC_CTRS) {
804 		smmu_pmu->reloc_base = devm_platform_ioremap_resource(pdev, 1);
805 		if (IS_ERR(smmu_pmu->reloc_base))
806 			return PTR_ERR(smmu_pmu->reloc_base);
807 	} else {
808 		smmu_pmu->reloc_base = smmu_pmu->reg_base;
809 	}
810 
811 	irq = platform_get_irq_optional(pdev, 0);
812 	if (irq > 0)
813 		smmu_pmu->irq = irq;
814 
815 	ceid_64[0] = readq_relaxed(smmu_pmu->reg_base + SMMU_PMCG_CEID0);
816 	ceid_64[1] = readq_relaxed(smmu_pmu->reg_base + SMMU_PMCG_CEID1);
817 	bitmap_from_arr32(smmu_pmu->supported_events, (u32 *)ceid_64,
818 			  SMMU_PMCG_ARCH_MAX_EVENTS);
819 
820 	smmu_pmu->num_counters = FIELD_GET(SMMU_PMCG_CFGR_NCTR, cfgr) + 1;
821 
822 	smmu_pmu->global_filter = !!(cfgr & SMMU_PMCG_CFGR_SID_FILTER_TYPE);
823 
824 	reg_size = FIELD_GET(SMMU_PMCG_CFGR_SIZE, cfgr);
825 	smmu_pmu->counter_mask = GENMASK_ULL(reg_size, 0);
826 
827 	smmu_pmu_reset(smmu_pmu);
828 
829 	err = smmu_pmu_setup_irq(smmu_pmu);
830 	if (err) {
831 		dev_err(dev, "Setup irq failed, PMU @%pa\n", &res_0->start);
832 		return err;
833 	}
834 
835 	smmu_pmu->iidr = readl_relaxed(smmu_pmu->reg_base + SMMU_PMCG_IIDR);
836 
837 	name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "smmuv3_pmcg_%llx",
838 			      (res_0->start) >> SMMU_PMCG_PA_SHIFT);
839 	if (!name) {
840 		dev_err(dev, "Create name failed, PMU @%pa\n", &res_0->start);
841 		return -EINVAL;
842 	}
843 
844 	smmu_pmu_get_acpi_options(smmu_pmu);
845 
846 	/* Pick one CPU to be the preferred one to use */
847 	smmu_pmu->on_cpu = raw_smp_processor_id();
848 	WARN_ON(irq_set_affinity_hint(smmu_pmu->irq,
849 				      cpumask_of(smmu_pmu->on_cpu)));
850 
851 	err = cpuhp_state_add_instance_nocalls(cpuhp_state_num,
852 					       &smmu_pmu->node);
853 	if (err) {
854 		dev_err(dev, "Error %d registering hotplug, PMU @%pa\n",
855 			err, &res_0->start);
856 		goto out_clear_affinity;
857 	}
858 
859 	err = perf_pmu_register(&smmu_pmu->pmu, name, -1);
860 	if (err) {
861 		dev_err(dev, "Error %d registering PMU @%pa\n",
862 			err, &res_0->start);
863 		goto out_unregister;
864 	}
865 
866 	dev_info(dev, "Registered PMU @ %pa using %d counters with %s filter settings\n",
867 		 &res_0->start, smmu_pmu->num_counters,
868 		 smmu_pmu->global_filter ? "Global(Counter0)" :
869 		 "Individual");
870 
871 	return 0;
872 
873 out_unregister:
874 	cpuhp_state_remove_instance_nocalls(cpuhp_state_num, &smmu_pmu->node);
875 out_clear_affinity:
876 	irq_set_affinity_hint(smmu_pmu->irq, NULL);
877 	return err;
878 }
879 
880 static int smmu_pmu_remove(struct platform_device *pdev)
881 {
882 	struct smmu_pmu *smmu_pmu = platform_get_drvdata(pdev);
883 
884 	perf_pmu_unregister(&smmu_pmu->pmu);
885 	cpuhp_state_remove_instance_nocalls(cpuhp_state_num, &smmu_pmu->node);
886 	irq_set_affinity_hint(smmu_pmu->irq, NULL);
887 
888 	return 0;
889 }
890 
891 static void smmu_pmu_shutdown(struct platform_device *pdev)
892 {
893 	struct smmu_pmu *smmu_pmu = platform_get_drvdata(pdev);
894 
895 	smmu_pmu_disable(&smmu_pmu->pmu);
896 }
897 
898 static struct platform_driver smmu_pmu_driver = {
899 	.driver = {
900 		.name = "arm-smmu-v3-pmcg",
901 		.suppress_bind_attrs = true,
902 	},
903 	.probe = smmu_pmu_probe,
904 	.remove = smmu_pmu_remove,
905 	.shutdown = smmu_pmu_shutdown,
906 };
907 
908 static int __init arm_smmu_pmu_init(void)
909 {
910 	cpuhp_state_num = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN,
911 						  "perf/arm/pmcg:online",
912 						  NULL,
913 						  smmu_pmu_offline_cpu);
914 	if (cpuhp_state_num < 0)
915 		return cpuhp_state_num;
916 
917 	return platform_driver_register(&smmu_pmu_driver);
918 }
919 module_init(arm_smmu_pmu_init);
920 
921 static void __exit arm_smmu_pmu_exit(void)
922 {
923 	platform_driver_unregister(&smmu_pmu_driver);
924 	cpuhp_remove_multi_state(cpuhp_state_num);
925 }
926 
927 module_exit(arm_smmu_pmu_exit);
928 
929 MODULE_DESCRIPTION("PMU driver for ARM SMMUv3 Performance Monitors Extension");
930 MODULE_AUTHOR("Neil Leeder <nleeder@codeaurora.org>");
931 MODULE_AUTHOR("Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>");
932 MODULE_LICENSE("GPL v2");
933