1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Driver for the L3 cache PMUs in Qualcomm Technologies chips.
4 *
5 * The driver supports a distributed cache architecture where the overall
6 * cache for a socket is comprised of multiple slices each with its own PMU.
7 * Access to each individual PMU is provided even though all CPUs share all
8 * the slices. User space needs to aggregate to individual counts to provide
9 * a global picture.
10 *
11 * See Documentation/admin-guide/perf/qcom_l3_pmu.rst for more details.
12 *
13 * Copyright (c) 2015-2017, The Linux Foundation. All rights reserved.
14 */
15
16#include <linux/acpi.h>
17#include <linux/bitops.h>
18#include <linux/interrupt.h>
19#include <linux/io.h>
20#include <linux/list.h>
21#include <linux/module.h>
22#include <linux/perf_event.h>
23#include <linux/platform_device.h>
24
25/*
26 * General constants
27 */
28
29/* Number of counters on each PMU */
30#define L3_NUM_COUNTERS  8
31/* Mask for the event type field within perf_event_attr.config and EVTYPE reg */
32#define L3_EVTYPE_MASK   0xFF
33/*
34 * Bit position of the 'long counter' flag within perf_event_attr.config.
35 * Reserve some space between the event type and this flag to allow expansion
36 * in the event type field.
37 */
38#define L3_EVENT_LC_BIT  32
39
40/*
41 * Register offsets
42 */
43
44/* Perfmon registers */
45#define L3_HML3_PM_CR       0x000
46#define L3_HML3_PM_EVCNTR(__cntr) (0x420 + ((__cntr) & 0x7) * 8)
47#define L3_HML3_PM_CNTCTL(__cntr) (0x120 + ((__cntr) & 0x7) * 8)
48#define L3_HML3_PM_EVTYPE(__cntr) (0x220 + ((__cntr) & 0x7) * 8)
49#define L3_HML3_PM_FILTRA   0x300
50#define L3_HML3_PM_FILTRB   0x308
51#define L3_HML3_PM_FILTRC   0x310
52#define L3_HML3_PM_FILTRAM  0x304
53#define L3_HML3_PM_FILTRBM  0x30C
54#define L3_HML3_PM_FILTRCM  0x314
55
56/* Basic counter registers */
57#define L3_M_BC_CR         0x500
58#define L3_M_BC_SATROLL_CR 0x504
59#define L3_M_BC_CNTENSET   0x508
60#define L3_M_BC_CNTENCLR   0x50C
61#define L3_M_BC_INTENSET   0x510
62#define L3_M_BC_INTENCLR   0x514
63#define L3_M_BC_GANG       0x718
64#define L3_M_BC_OVSR       0x740
65#define L3_M_BC_IRQCTL     0x96C
66
67/*
68 * Bit field definitions
69 */
70
71/* L3_HML3_PM_CR */
72#define PM_CR_RESET           (0)
73
74/* L3_HML3_PM_XCNTCTL/L3_HML3_PM_CNTCTLx */
75#define PMCNT_RESET           (0)
76
77/* L3_HML3_PM_EVTYPEx */
78#define EVSEL(__val)          ((__val) & L3_EVTYPE_MASK)
79
80/* Reset value for all the filter registers */
81#define PM_FLTR_RESET         (0)
82
83/* L3_M_BC_CR */
84#define BC_RESET              (1UL << 1)
85#define BC_ENABLE             (1UL << 0)
86
87/* L3_M_BC_SATROLL_CR */
88#define BC_SATROLL_CR_RESET   (0)
89
90/* L3_M_BC_CNTENSET */
91#define PMCNTENSET(__cntr)    (1UL << ((__cntr) & 0x7))
92
93/* L3_M_BC_CNTENCLR */
94#define PMCNTENCLR(__cntr)    (1UL << ((__cntr) & 0x7))
95#define BC_CNTENCLR_RESET     (0xFF)
96
97/* L3_M_BC_INTENSET */
98#define PMINTENSET(__cntr)    (1UL << ((__cntr) & 0x7))
99
100/* L3_M_BC_INTENCLR */
101#define PMINTENCLR(__cntr)    (1UL << ((__cntr) & 0x7))
102#define BC_INTENCLR_RESET     (0xFF)
103
104/* L3_M_BC_GANG */
105#define GANG_EN(__cntr)       (1UL << ((__cntr) & 0x7))
106#define BC_GANG_RESET         (0)
107
108/* L3_M_BC_OVSR */
109#define PMOVSRCLR(__cntr)     (1UL << ((__cntr) & 0x7))
110#define PMOVSRCLR_RESET       (0xFF)
111
112/* L3_M_BC_IRQCTL */
113#define PMIRQONMSBEN(__cntr)  (1UL << ((__cntr) & 0x7))
114#define BC_IRQCTL_RESET       (0x0)
115
116/*
117 * Events
118 */
119
120#define L3_EVENT_CYCLES		0x01
121#define L3_EVENT_READ_HIT		0x20
122#define L3_EVENT_READ_MISS		0x21
123#define L3_EVENT_READ_HIT_D		0x22
124#define L3_EVENT_READ_MISS_D		0x23
125#define L3_EVENT_WRITE_HIT		0x24
126#define L3_EVENT_WRITE_MISS		0x25
127
128/*
129 * Decoding of settings from perf_event_attr
130 *
131 * The config format for perf events is:
132 * - config: bits 0-7: event type
133 *           bit  32:  HW counter size requested, 0: 32 bits, 1: 64 bits
134 */
135
136static inline u32 get_event_type(struct perf_event *event)
137{
138	return (event->attr.config) & L3_EVTYPE_MASK;
139}
140
141static inline bool event_uses_long_counter(struct perf_event *event)
142{
143	return !!(event->attr.config & BIT_ULL(L3_EVENT_LC_BIT));
144}
145
146static inline int event_num_counters(struct perf_event *event)
147{
148	return event_uses_long_counter(event) ? 2 : 1;
149}
150
151/*
152 * Main PMU, inherits from the core perf PMU type
153 */
154struct l3cache_pmu {
155	struct pmu		pmu;
156	struct hlist_node	node;
157	void __iomem		*regs;
158	struct perf_event	*events[L3_NUM_COUNTERS];
159	unsigned long		used_mask[BITS_TO_LONGS(L3_NUM_COUNTERS)];
160	cpumask_t		cpumask;
161};
162
163#define to_l3cache_pmu(p) (container_of(p, struct l3cache_pmu, pmu))
164
165/*
166 * Type used to group hardware counter operations
167 *
168 * Used to implement two types of hardware counters, standard (32bits) and
169 * long (64bits). The hardware supports counter chaining which we use to
170 * implement long counters. This support is exposed via the 'lc' flag field
171 * in perf_event_attr.config.
172 */
173struct l3cache_event_ops {
174	/* Called to start event monitoring */
175	void (*start)(struct perf_event *event);
176	/* Called to stop event monitoring */
177	void (*stop)(struct perf_event *event, int flags);
178	/* Called to update the perf_event */
179	void (*update)(struct perf_event *event);
180};
181
182/*
183 * Implementation of long counter operations
184 *
185 * 64bit counters are implemented by chaining two of the 32bit physical
186 * counters. The PMU only supports chaining of adjacent even/odd pairs
187 * and for simplicity the driver always configures the odd counter to
188 * count the overflows of the lower-numbered even counter. Note that since
189 * the resulting hardware counter is 64bits no IRQs are required to maintain
190 * the software counter which is also 64bits.
191 */
192
193static void qcom_l3_cache__64bit_counter_start(struct perf_event *event)
194{
195	struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu);
196	int idx = event->hw.idx;
197	u32 evsel = get_event_type(event);
198	u32 gang;
199
200	/* Set the odd counter to count the overflows of the even counter */
201	gang = readl_relaxed(l3pmu->regs + L3_M_BC_GANG);
202	gang |= GANG_EN(idx + 1);
203	writel_relaxed(gang, l3pmu->regs + L3_M_BC_GANG);
204
205	/* Initialize the hardware counters and reset prev_count*/
206	local64_set(&event->hw.prev_count, 0);
207	writel_relaxed(0, l3pmu->regs + L3_HML3_PM_EVCNTR(idx + 1));
208	writel_relaxed(0, l3pmu->regs + L3_HML3_PM_EVCNTR(idx));
209
210	/*
211	 * Set the event types, the upper half must use zero and the lower
212	 * half the actual event type
213	 */
214	writel_relaxed(EVSEL(0), l3pmu->regs + L3_HML3_PM_EVTYPE(idx + 1));
215	writel_relaxed(EVSEL(evsel), l3pmu->regs + L3_HML3_PM_EVTYPE(idx));
216
217	/* Finally, enable the counters */
218	writel_relaxed(PMCNT_RESET, l3pmu->regs + L3_HML3_PM_CNTCTL(idx + 1));
219	writel_relaxed(PMCNTENSET(idx + 1), l3pmu->regs + L3_M_BC_CNTENSET);
220	writel_relaxed(PMCNT_RESET, l3pmu->regs + L3_HML3_PM_CNTCTL(idx));
221	writel_relaxed(PMCNTENSET(idx), l3pmu->regs + L3_M_BC_CNTENSET);
222}
223
224static void qcom_l3_cache__64bit_counter_stop(struct perf_event *event,
225					      int flags)
226{
227	struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu);
228	int idx = event->hw.idx;
229	u32 gang = readl_relaxed(l3pmu->regs + L3_M_BC_GANG);
230
231	/* Disable the counters */
232	writel_relaxed(PMCNTENCLR(idx), l3pmu->regs + L3_M_BC_CNTENCLR);
233	writel_relaxed(PMCNTENCLR(idx + 1), l3pmu->regs + L3_M_BC_CNTENCLR);
234
235	/* Disable chaining */
236	writel_relaxed(gang & ~GANG_EN(idx + 1), l3pmu->regs + L3_M_BC_GANG);
237}
238
239static void qcom_l3_cache__64bit_counter_update(struct perf_event *event)
240{
241	struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu);
242	int idx = event->hw.idx;
243	u32 hi, lo;
244	u64 prev, new;
245
246	do {
247		prev = local64_read(&event->hw.prev_count);
248		do {
249			hi = readl_relaxed(l3pmu->regs + L3_HML3_PM_EVCNTR(idx + 1));
250			lo = readl_relaxed(l3pmu->regs + L3_HML3_PM_EVCNTR(idx));
251		} while (hi != readl_relaxed(l3pmu->regs + L3_HML3_PM_EVCNTR(idx + 1)));
252		new = ((u64)hi << 32) | lo;
253	} while (local64_cmpxchg(&event->hw.prev_count, prev, new) != prev);
254
255	local64_add(new - prev, &event->count);
256}
257
258static const struct l3cache_event_ops event_ops_long = {
259	.start = qcom_l3_cache__64bit_counter_start,
260	.stop = qcom_l3_cache__64bit_counter_stop,
261	.update = qcom_l3_cache__64bit_counter_update,
262};
263
264/*
265 * Implementation of standard counter operations
266 *
267 * 32bit counters use a single physical counter and a hardware feature that
268 * asserts the overflow IRQ on the toggling of the most significant bit in
269 * the counter. This feature allows the counters to be left free-running
270 * without needing the usual reprogramming required to properly handle races
271 * during concurrent calls to update.
272 */
273
274static void qcom_l3_cache__32bit_counter_start(struct perf_event *event)
275{
276	struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu);
277	int idx = event->hw.idx;
278	u32 evsel = get_event_type(event);
279	u32 irqctl = readl_relaxed(l3pmu->regs + L3_M_BC_IRQCTL);
280
281	/* Set the counter to assert the overflow IRQ on MSB toggling */
282	writel_relaxed(irqctl | PMIRQONMSBEN(idx), l3pmu->regs + L3_M_BC_IRQCTL);
283
284	/* Initialize the hardware counter and reset prev_count*/
285	local64_set(&event->hw.prev_count, 0);
286	writel_relaxed(0, l3pmu->regs + L3_HML3_PM_EVCNTR(idx));
287
288	/* Set the event type */
289	writel_relaxed(EVSEL(evsel), l3pmu->regs + L3_HML3_PM_EVTYPE(idx));
290
291	/* Enable interrupt generation by this counter */
292	writel_relaxed(PMINTENSET(idx), l3pmu->regs + L3_M_BC_INTENSET);
293
294	/* Finally, enable the counter */
295	writel_relaxed(PMCNT_RESET, l3pmu->regs + L3_HML3_PM_CNTCTL(idx));
296	writel_relaxed(PMCNTENSET(idx), l3pmu->regs + L3_M_BC_CNTENSET);
297}
298
299static void qcom_l3_cache__32bit_counter_stop(struct perf_event *event,
300					      int flags)
301{
302	struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu);
303	int idx = event->hw.idx;
304	u32 irqctl = readl_relaxed(l3pmu->regs + L3_M_BC_IRQCTL);
305
306	/* Disable the counter */
307	writel_relaxed(PMCNTENCLR(idx), l3pmu->regs + L3_M_BC_CNTENCLR);
308
309	/* Disable interrupt generation by this counter */
310	writel_relaxed(PMINTENCLR(idx), l3pmu->regs + L3_M_BC_INTENCLR);
311
312	/* Set the counter to not assert the overflow IRQ on MSB toggling */
313	writel_relaxed(irqctl & ~PMIRQONMSBEN(idx), l3pmu->regs + L3_M_BC_IRQCTL);
314}
315
316static void qcom_l3_cache__32bit_counter_update(struct perf_event *event)
317{
318	struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu);
319	int idx = event->hw.idx;
320	u32 prev, new;
321
322	do {
323		prev = local64_read(&event->hw.prev_count);
324		new = readl_relaxed(l3pmu->regs + L3_HML3_PM_EVCNTR(idx));
325	} while (local64_cmpxchg(&event->hw.prev_count, prev, new) != prev);
326
327	local64_add(new - prev, &event->count);
328}
329
330static const struct l3cache_event_ops event_ops_std = {
331	.start = qcom_l3_cache__32bit_counter_start,
332	.stop = qcom_l3_cache__32bit_counter_stop,
333	.update = qcom_l3_cache__32bit_counter_update,
334};
335
336/* Retrieve the appropriate operations for the given event */
337static
338const struct l3cache_event_ops *l3cache_event_get_ops(struct perf_event *event)
339{
340	if (event_uses_long_counter(event))
341		return &event_ops_long;
342	else
343		return &event_ops_std;
344}
345
346/*
347 * Top level PMU functions.
348 */
349
350static inline void qcom_l3_cache__init(struct l3cache_pmu *l3pmu)
351{
352	int i;
353
354	writel_relaxed(BC_RESET, l3pmu->regs + L3_M_BC_CR);
355
356	/*
357	 * Use writel for the first programming command to ensure the basic
358	 * counter unit is stopped before proceeding
359	 */
360	writel(BC_SATROLL_CR_RESET, l3pmu->regs + L3_M_BC_SATROLL_CR);
361
362	writel_relaxed(BC_CNTENCLR_RESET, l3pmu->regs + L3_M_BC_CNTENCLR);
363	writel_relaxed(BC_INTENCLR_RESET, l3pmu->regs + L3_M_BC_INTENCLR);
364	writel_relaxed(PMOVSRCLR_RESET, l3pmu->regs + L3_M_BC_OVSR);
365	writel_relaxed(BC_GANG_RESET, l3pmu->regs + L3_M_BC_GANG);
366	writel_relaxed(BC_IRQCTL_RESET, l3pmu->regs + L3_M_BC_IRQCTL);
367	writel_relaxed(PM_CR_RESET, l3pmu->regs + L3_HML3_PM_CR);
368
369	for (i = 0; i < L3_NUM_COUNTERS; ++i) {
370		writel_relaxed(PMCNT_RESET, l3pmu->regs + L3_HML3_PM_CNTCTL(i));
371		writel_relaxed(EVSEL(0), l3pmu->regs + L3_HML3_PM_EVTYPE(i));
372	}
373
374	writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRA);
375	writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRAM);
376	writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRB);
377	writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRBM);
378	writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRC);
379	writel_relaxed(PM_FLTR_RESET, l3pmu->regs + L3_HML3_PM_FILTRCM);
380
381	/*
382	 * Use writel here to ensure all programming commands are done
383	 *  before proceeding
384	 */
385	writel(BC_ENABLE, l3pmu->regs + L3_M_BC_CR);
386}
387
388static irqreturn_t qcom_l3_cache__handle_irq(int irq_num, void *data)
389{
390	struct l3cache_pmu *l3pmu = data;
391	/* Read the overflow status register */
392	long status = readl_relaxed(l3pmu->regs + L3_M_BC_OVSR);
393	int idx;
394
395	if (status == 0)
396		return IRQ_NONE;
397
398	/* Clear the bits we read on the overflow status register */
399	writel_relaxed(status, l3pmu->regs + L3_M_BC_OVSR);
400
401	for_each_set_bit(idx, &status, L3_NUM_COUNTERS) {
402		struct perf_event *event;
403		const struct l3cache_event_ops *ops;
404
405		event = l3pmu->events[idx];
406		if (!event)
407			continue;
408
409		/*
410		 * Since the IRQ is not enabled for events using long counters
411		 * we should never see one of those here, however, be consistent
412		 * and use the ops indirections like in the other operations.
413		 */
414
415		ops = l3cache_event_get_ops(event);
416		ops->update(event);
417	}
418
419	return IRQ_HANDLED;
420}
421
422/*
423 * Implementation of abstract pmu functionality required by
424 * the core perf events code.
425 */
426
427static void qcom_l3_cache__pmu_enable(struct pmu *pmu)
428{
429	struct l3cache_pmu *l3pmu = to_l3cache_pmu(pmu);
430
431	/* Ensure the other programming commands are observed before enabling */
432	wmb();
433
434	writel_relaxed(BC_ENABLE, l3pmu->regs + L3_M_BC_CR);
435}
436
437static void qcom_l3_cache__pmu_disable(struct pmu *pmu)
438{
439	struct l3cache_pmu *l3pmu = to_l3cache_pmu(pmu);
440
441	writel_relaxed(0, l3pmu->regs + L3_M_BC_CR);
442
443	/* Ensure the basic counter unit is stopped before proceeding */
444	wmb();
445}
446
447/*
448 * We must NOT create groups containing events from multiple hardware PMUs,
449 * although mixing different software and hardware PMUs is allowed.
450 */
451static bool qcom_l3_cache__validate_event_group(struct perf_event *event)
452{
453	struct perf_event *leader = event->group_leader;
454	struct perf_event *sibling;
455	int counters = 0;
456
457	if (leader->pmu != event->pmu && !is_software_event(leader))
458		return false;
459
460	counters = event_num_counters(event);
461	counters += event_num_counters(leader);
462
463	for_each_sibling_event(sibling, leader) {
464		if (is_software_event(sibling))
465			continue;
466		if (sibling->pmu != event->pmu)
467			return false;
468		counters += event_num_counters(sibling);
469	}
470
471	/*
472	 * If the group requires more counters than the HW has, it
473	 * cannot ever be scheduled.
474	 */
475	return counters <= L3_NUM_COUNTERS;
476}
477
478static int qcom_l3_cache__event_init(struct perf_event *event)
479{
480	struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu);
481	struct hw_perf_event *hwc = &event->hw;
482
483	/*
484	 * Is the event for this PMU?
485	 */
486	if (event->attr.type != event->pmu->type)
487		return -ENOENT;
488
489	/*
490	 * Sampling not supported since these events are not core-attributable.
491	 */
492	if (hwc->sample_period)
493		return -EINVAL;
494
495	/*
496	 * Task mode not available, we run the counters as socket counters,
497	 * not attributable to any CPU and therefore cannot attribute per-task.
498	 */
499	if (event->cpu < 0)
500		return -EINVAL;
501
502	/* Validate the group */
503	if (!qcom_l3_cache__validate_event_group(event))
504		return -EINVAL;
505
506	hwc->idx = -1;
507
508	/*
509	 * Many perf core operations (eg. events rotation) operate on a
510	 * single CPU context. This is obvious for CPU PMUs, where one
511	 * expects the same sets of events being observed on all CPUs,
512	 * but can lead to issues for off-core PMUs, like this one, where
513	 * each event could be theoretically assigned to a different CPU.
514	 * To mitigate this, we enforce CPU assignment to one designated
515	 * processor (the one described in the "cpumask" attribute exported
516	 * by the PMU device). perf user space tools honor this and avoid
517	 * opening more than one copy of the events.
518	 */
519	event->cpu = cpumask_first(&l3pmu->cpumask);
520
521	return 0;
522}
523
524static void qcom_l3_cache__event_start(struct perf_event *event, int flags)
525{
526	struct hw_perf_event *hwc = &event->hw;
527	const struct l3cache_event_ops *ops = l3cache_event_get_ops(event);
528
529	hwc->state = 0;
530	ops->start(event);
531}
532
533static void qcom_l3_cache__event_stop(struct perf_event *event, int flags)
534{
535	struct hw_perf_event *hwc = &event->hw;
536	const struct l3cache_event_ops *ops = l3cache_event_get_ops(event);
537
538	if (hwc->state & PERF_HES_STOPPED)
539		return;
540
541	ops->stop(event, flags);
542	if (flags & PERF_EF_UPDATE)
543		ops->update(event);
544	hwc->state |= PERF_HES_STOPPED | PERF_HES_UPTODATE;
545}
546
547static int qcom_l3_cache__event_add(struct perf_event *event, int flags)
548{
549	struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu);
550	struct hw_perf_event *hwc = &event->hw;
551	int order = event_uses_long_counter(event) ? 1 : 0;
552	int idx;
553
554	/*
555	 * Try to allocate a counter.
556	 */
557	idx = bitmap_find_free_region(l3pmu->used_mask, L3_NUM_COUNTERS, order);
558	if (idx < 0)
559		/* The counters are all in use. */
560		return -EAGAIN;
561
562	hwc->idx = idx;
563	hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
564	l3pmu->events[idx] = event;
565
566	if (flags & PERF_EF_START)
567		qcom_l3_cache__event_start(event, 0);
568
569	/* Propagate changes to the userspace mapping. */
570	perf_event_update_userpage(event);
571
572	return 0;
573}
574
575static void qcom_l3_cache__event_del(struct perf_event *event, int flags)
576{
577	struct l3cache_pmu *l3pmu = to_l3cache_pmu(event->pmu);
578	struct hw_perf_event *hwc = &event->hw;
579	int order = event_uses_long_counter(event) ? 1 : 0;
580
581	/* Stop and clean up */
582	qcom_l3_cache__event_stop(event,  flags | PERF_EF_UPDATE);
583	l3pmu->events[hwc->idx] = NULL;
584	bitmap_release_region(l3pmu->used_mask, hwc->idx, order);
585
586	/* Propagate changes to the userspace mapping. */
587	perf_event_update_userpage(event);
588}
589
590static void qcom_l3_cache__event_read(struct perf_event *event)
591{
592	const struct l3cache_event_ops *ops = l3cache_event_get_ops(event);
593
594	ops->update(event);
595}
596
597/*
598 * Add sysfs attributes
599 *
600 * We export:
601 * - formats, used by perf user space and other tools to configure events
602 * - events, used by perf user space and other tools to create events
603 *   symbolically, e.g.:
604 *     perf stat -a -e l3cache_0_0/event=read-miss/ ls
605 *     perf stat -a -e l3cache_0_0/event=0x21/ ls
606 * - cpumask, used by perf user space and other tools to know on which CPUs
607 *   to open the events
608 */
609
610/* formats */
611
612static ssize_t l3cache_pmu_format_show(struct device *dev,
613				       struct device_attribute *attr, char *buf)
614{
615	struct dev_ext_attribute *eattr;
616
617	eattr = container_of(attr, struct dev_ext_attribute, attr);
618	return sysfs_emit(buf, "%s\n", (char *) eattr->var);
619}
620
621#define L3CACHE_PMU_FORMAT_ATTR(_name, _config)				      \
622	(&((struct dev_ext_attribute[]) {				      \
623		{ .attr = __ATTR(_name, 0444, l3cache_pmu_format_show, NULL), \
624		  .var = (void *) _config, }				      \
625	})[0].attr.attr)
626
627static struct attribute *qcom_l3_cache_pmu_formats[] = {
628	L3CACHE_PMU_FORMAT_ATTR(event, "config:0-7"),
629	L3CACHE_PMU_FORMAT_ATTR(lc, "config:" __stringify(L3_EVENT_LC_BIT)),
630	NULL,
631};
632
633static const struct attribute_group qcom_l3_cache_pmu_format_group = {
634	.name = "format",
635	.attrs = qcom_l3_cache_pmu_formats,
636};
637
638/* events */
639
640static ssize_t l3cache_pmu_event_show(struct device *dev,
641				     struct device_attribute *attr, char *page)
642{
643	struct perf_pmu_events_attr *pmu_attr;
644
645	pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr);
646	return sysfs_emit(page, "event=0x%02llx\n", pmu_attr->id);
647}
648
649#define L3CACHE_EVENT_ATTR(_name, _id)					     \
650	PMU_EVENT_ATTR_ID(_name, l3cache_pmu_event_show, _id)
651
652static struct attribute *qcom_l3_cache_pmu_events[] = {
653	L3CACHE_EVENT_ATTR(cycles, L3_EVENT_CYCLES),
654	L3CACHE_EVENT_ATTR(read-hit, L3_EVENT_READ_HIT),
655	L3CACHE_EVENT_ATTR(read-miss, L3_EVENT_READ_MISS),
656	L3CACHE_EVENT_ATTR(read-hit-d-side, L3_EVENT_READ_HIT_D),
657	L3CACHE_EVENT_ATTR(read-miss-d-side, L3_EVENT_READ_MISS_D),
658	L3CACHE_EVENT_ATTR(write-hit, L3_EVENT_WRITE_HIT),
659	L3CACHE_EVENT_ATTR(write-miss, L3_EVENT_WRITE_MISS),
660	NULL
661};
662
663static const struct attribute_group qcom_l3_cache_pmu_events_group = {
664	.name = "events",
665	.attrs = qcom_l3_cache_pmu_events,
666};
667
668/* cpumask */
669
670static ssize_t cpumask_show(struct device *dev,
671			    struct device_attribute *attr, char *buf)
672{
673	struct l3cache_pmu *l3pmu = to_l3cache_pmu(dev_get_drvdata(dev));
674
675	return cpumap_print_to_pagebuf(true, buf, &l3pmu->cpumask);
676}
677
678static DEVICE_ATTR_RO(cpumask);
679
680static struct attribute *qcom_l3_cache_pmu_cpumask_attrs[] = {
681	&dev_attr_cpumask.attr,
682	NULL,
683};
684
685static const struct attribute_group qcom_l3_cache_pmu_cpumask_attr_group = {
686	.attrs = qcom_l3_cache_pmu_cpumask_attrs,
687};
688
689/*
690 * Per PMU device attribute groups
691 */
692static const struct attribute_group *qcom_l3_cache_pmu_attr_grps[] = {
693	&qcom_l3_cache_pmu_format_group,
694	&qcom_l3_cache_pmu_events_group,
695	&qcom_l3_cache_pmu_cpumask_attr_group,
696	NULL,
697};
698
699/*
700 * Probing functions and data.
701 */
702
703static int qcom_l3_cache_pmu_online_cpu(unsigned int cpu, struct hlist_node *node)
704{
705	struct l3cache_pmu *l3pmu = hlist_entry_safe(node, struct l3cache_pmu, node);
706
707	/* If there is not a CPU/PMU association pick this CPU */
708	if (cpumask_empty(&l3pmu->cpumask))
709		cpumask_set_cpu(cpu, &l3pmu->cpumask);
710
711	return 0;
712}
713
714static int qcom_l3_cache_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
715{
716	struct l3cache_pmu *l3pmu = hlist_entry_safe(node, struct l3cache_pmu, node);
717	unsigned int target;
718
719	if (!cpumask_test_and_clear_cpu(cpu, &l3pmu->cpumask))
720		return 0;
721	target = cpumask_any_but(cpu_online_mask, cpu);
722	if (target >= nr_cpu_ids)
723		return 0;
724	perf_pmu_migrate_context(&l3pmu->pmu, cpu, target);
725	cpumask_set_cpu(target, &l3pmu->cpumask);
726	return 0;
727}
728
729static int qcom_l3_cache_pmu_probe(struct platform_device *pdev)
730{
731	struct l3cache_pmu *l3pmu;
732	struct acpi_device *acpi_dev;
733	struct resource *memrc;
734	int ret;
735	char *name;
736
737	/* Initialize the PMU data structures */
738
739	acpi_dev = ACPI_COMPANION(&pdev->dev);
740	if (!acpi_dev)
741		return -ENODEV;
742
743	l3pmu = devm_kzalloc(&pdev->dev, sizeof(*l3pmu), GFP_KERNEL);
744	name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "l3cache_%s_%s",
745		      acpi_device_uid(acpi_dev_parent(acpi_dev)),
746		      acpi_device_uid(acpi_dev));
747	if (!l3pmu || !name)
748		return -ENOMEM;
749
750	l3pmu->pmu = (struct pmu) {
751		.task_ctx_nr	= perf_invalid_context,
752
753		.pmu_enable	= qcom_l3_cache__pmu_enable,
754		.pmu_disable	= qcom_l3_cache__pmu_disable,
755		.event_init	= qcom_l3_cache__event_init,
756		.add		= qcom_l3_cache__event_add,
757		.del		= qcom_l3_cache__event_del,
758		.start		= qcom_l3_cache__event_start,
759		.stop		= qcom_l3_cache__event_stop,
760		.read		= qcom_l3_cache__event_read,
761
762		.attr_groups	= qcom_l3_cache_pmu_attr_grps,
763		.capabilities	= PERF_PMU_CAP_NO_EXCLUDE,
764	};
765
766	l3pmu->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &memrc);
767	if (IS_ERR(l3pmu->regs))
768		return PTR_ERR(l3pmu->regs);
769
770	qcom_l3_cache__init(l3pmu);
771
772	ret = platform_get_irq(pdev, 0);
773	if (ret <= 0)
774		return ret;
775
776	ret = devm_request_irq(&pdev->dev, ret, qcom_l3_cache__handle_irq, 0,
777			       name, l3pmu);
778	if (ret) {
779		dev_err(&pdev->dev, "Request for IRQ failed for slice @%pa\n",
780			&memrc->start);
781		return ret;
782	}
783
784	/* Add this instance to the list used by the offline callback */
785	ret = cpuhp_state_add_instance(CPUHP_AP_PERF_ARM_QCOM_L3_ONLINE, &l3pmu->node);
786	if (ret) {
787		dev_err(&pdev->dev, "Error %d registering hotplug", ret);
788		return ret;
789	}
790
791	ret = perf_pmu_register(&l3pmu->pmu, name, -1);
792	if (ret < 0) {
793		dev_err(&pdev->dev, "Failed to register L3 cache PMU (%d)\n", ret);
794		return ret;
795	}
796
797	dev_info(&pdev->dev, "Registered %s, type: %d\n", name, l3pmu->pmu.type);
798
799	return 0;
800}
801
802static const struct acpi_device_id qcom_l3_cache_pmu_acpi_match[] = {
803	{ "QCOM8081", },
804	{ }
805};
806MODULE_DEVICE_TABLE(acpi, qcom_l3_cache_pmu_acpi_match);
807
808static struct platform_driver qcom_l3_cache_pmu_driver = {
809	.driver = {
810		.name = "qcom-l3cache-pmu",
811		.acpi_match_table = ACPI_PTR(qcom_l3_cache_pmu_acpi_match),
812		.suppress_bind_attrs = true,
813	},
814	.probe = qcom_l3_cache_pmu_probe,
815};
816
817static int __init register_qcom_l3_cache_pmu_driver(void)
818{
819	int ret;
820
821	/* Install a hook to update the reader CPU in case it goes offline */
822	ret = cpuhp_setup_state_multi(CPUHP_AP_PERF_ARM_QCOM_L3_ONLINE,
823				      "perf/qcom/l3cache:online",
824				      qcom_l3_cache_pmu_online_cpu,
825				      qcom_l3_cache_pmu_offline_cpu);
826	if (ret)
827		return ret;
828
829	return platform_driver_register(&qcom_l3_cache_pmu_driver);
830}
831device_initcall(register_qcom_l3_cache_pmu_driver);
832