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[karo-tx-linux.git] / drivers / perf / qcom_l2_pmu.c
1 /* Copyright (c) 2015-2017 The Linux Foundation. All rights reserved.
2  *
3  * This program is free software; you can redistribute it and/or modify
4  * it under the terms of the GNU General Public License version 2 and
5  * only version 2 as published by the Free Software Foundation.
6  *
7  * This program is distributed in the hope that it will be useful,
8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
10  * GNU General Public License for more details.
11  */
12 #include <linux/acpi.h>
13 #include <linux/bitops.h>
14 #include <linux/bug.h>
15 #include <linux/cpuhotplug.h>
16 #include <linux/cpumask.h>
17 #include <linux/device.h>
18 #include <linux/errno.h>
19 #include <linux/interrupt.h>
20 #include <linux/irq.h>
21 #include <linux/kernel.h>
22 #include <linux/list.h>
23 #include <linux/percpu.h>
24 #include <linux/perf_event.h>
25 #include <linux/platform_device.h>
26 #include <linux/smp.h>
27 #include <linux/spinlock.h>
28 #include <linux/sysfs.h>
29 #include <linux/types.h>
30
31 #include <asm/barrier.h>
32 #include <asm/local64.h>
33 #include <asm/sysreg.h>
34
35 #define MAX_L2_CTRS             9
36
37 #define L2PMCR_NUM_EV_SHIFT     11
38 #define L2PMCR_NUM_EV_MASK      0x1F
39
40 #define L2PMCR                  0x400
41 #define L2PMCNTENCLR            0x403
42 #define L2PMCNTENSET            0x404
43 #define L2PMINTENCLR            0x405
44 #define L2PMINTENSET            0x406
45 #define L2PMOVSCLR              0x407
46 #define L2PMOVSSET              0x408
47 #define L2PMCCNTCR              0x409
48 #define L2PMCCNTR               0x40A
49 #define L2PMCCNTSR              0x40C
50 #define L2PMRESR                0x410
51 #define IA_L2PMXEVCNTCR_BASE    0x420
52 #define IA_L2PMXEVCNTR_BASE     0x421
53 #define IA_L2PMXEVFILTER_BASE   0x423
54 #define IA_L2PMXEVTYPER_BASE    0x424
55
56 #define IA_L2_REG_OFFSET        0x10
57
58 #define L2PMXEVFILTER_SUFILTER_ALL      0x000E0000
59 #define L2PMXEVFILTER_ORGFILTER_IDINDEP 0x00000004
60 #define L2PMXEVFILTER_ORGFILTER_ALL     0x00000003
61
62 #define L2EVTYPER_REG_SHIFT     3
63
64 #define L2PMRESR_GROUP_BITS     8
65 #define L2PMRESR_GROUP_MASK     GENMASK(7, 0)
66
67 #define L2CYCLE_CTR_BIT         31
68 #define L2CYCLE_CTR_RAW_CODE    0xFE
69
70 #define L2PMCR_RESET_ALL        0x6
71 #define L2PMCR_COUNTERS_ENABLE  0x1
72 #define L2PMCR_COUNTERS_DISABLE 0x0
73
74 #define L2PMRESR_EN             BIT_ULL(63)
75
76 #define L2_EVT_MASK             0x00000FFF
77 #define L2_EVT_CODE_MASK        0x00000FF0
78 #define L2_EVT_GRP_MASK         0x0000000F
79 #define L2_EVT_CODE_SHIFT       4
80 #define L2_EVT_GRP_SHIFT        0
81
82 #define L2_EVT_CODE(event)   (((event) & L2_EVT_CODE_MASK) >> L2_EVT_CODE_SHIFT)
83 #define L2_EVT_GROUP(event)  (((event) & L2_EVT_GRP_MASK) >> L2_EVT_GRP_SHIFT)
84
85 #define L2_EVT_GROUP_MAX        7
86
87 #define L2_COUNTER_RELOAD       BIT_ULL(31)
88 #define L2_CYCLE_COUNTER_RELOAD BIT_ULL(63)
89
90 #define L2CPUSRSELR_EL1         sys_reg(3, 3, 15, 0, 6)
91 #define L2CPUSRDR_EL1           sys_reg(3, 3, 15, 0, 7)
92
93 #define reg_idx(reg, i)         (((i) * IA_L2_REG_OFFSET) + reg##_BASE)
94
95 static DEFINE_RAW_SPINLOCK(l2_access_lock);
96
97 /**
98  * set_l2_indirect_reg: write value to an L2 register
99  * @reg: Address of L2 register.
100  * @value: Value to be written to register.
101  *
102  * Use architecturally required barriers for ordering between system register
103  * accesses
104  */
105 static void set_l2_indirect_reg(u64 reg, u64 val)
106 {
107         unsigned long flags;
108
109         raw_spin_lock_irqsave(&l2_access_lock, flags);
110         write_sysreg_s(reg, L2CPUSRSELR_EL1);
111         isb();
112         write_sysreg_s(val, L2CPUSRDR_EL1);
113         isb();
114         raw_spin_unlock_irqrestore(&l2_access_lock, flags);
115 }
116
117 /**
118  * get_l2_indirect_reg: read an L2 register value
119  * @reg: Address of L2 register.
120  *
121  * Use architecturally required barriers for ordering between system register
122  * accesses
123  */
124 static u64 get_l2_indirect_reg(u64 reg)
125 {
126         u64 val;
127         unsigned long flags;
128
129         raw_spin_lock_irqsave(&l2_access_lock, flags);
130         write_sysreg_s(reg, L2CPUSRSELR_EL1);
131         isb();
132         val = read_sysreg_s(L2CPUSRDR_EL1);
133         raw_spin_unlock_irqrestore(&l2_access_lock, flags);
134
135         return val;
136 }
137
138 struct cluster_pmu;
139
140 /*
141  * Aggregate PMU. Implements the core pmu functions and manages
142  * the hardware PMUs.
143  */
144 struct l2cache_pmu {
145         struct hlist_node node;
146         u32 num_pmus;
147         struct pmu pmu;
148         int num_counters;
149         cpumask_t cpumask;
150         struct platform_device *pdev;
151         struct cluster_pmu * __percpu *pmu_cluster;
152         struct list_head clusters;
153 };
154
155 /*
156  * The cache is made up of one or more clusters, each cluster has its own PMU.
157  * Each cluster is associated with one or more CPUs.
158  * This structure represents one of the hardware PMUs.
159  *
160  * Events can be envisioned as a 2-dimensional array. Each column represents
161  * a group of events. There are 8 groups. Only one entry from each
162  * group can be in use at a time.
163  *
164  * Events are specified as 0xCCG, where CC is 2 hex digits specifying
165  * the code (array row) and G specifies the group (column).
166  *
167  * In addition there is a cycle counter event specified by L2CYCLE_CTR_RAW_CODE
168  * which is outside the above scheme.
169  */
170 struct cluster_pmu {
171         struct list_head next;
172         struct perf_event *events[MAX_L2_CTRS];
173         struct l2cache_pmu *l2cache_pmu;
174         DECLARE_BITMAP(used_counters, MAX_L2_CTRS);
175         DECLARE_BITMAP(used_groups, L2_EVT_GROUP_MAX + 1);
176         int irq;
177         int cluster_id;
178         /* The CPU that is used for collecting events on this cluster */
179         int on_cpu;
180         /* All the CPUs associated with this cluster */
181         cpumask_t cluster_cpus;
182         spinlock_t pmu_lock;
183 };
184
185 #define to_l2cache_pmu(p) (container_of(p, struct l2cache_pmu, pmu))
186
187 static u32 l2_cycle_ctr_idx;
188 static u32 l2_counter_present_mask;
189
190 static inline u32 idx_to_reg_bit(u32 idx)
191 {
192         if (idx == l2_cycle_ctr_idx)
193                 return BIT(L2CYCLE_CTR_BIT);
194
195         return BIT(idx);
196 }
197
198 static inline struct cluster_pmu *get_cluster_pmu(
199         struct l2cache_pmu *l2cache_pmu, int cpu)
200 {
201         return *per_cpu_ptr(l2cache_pmu->pmu_cluster, cpu);
202 }
203
204 static void cluster_pmu_reset(void)
205 {
206         /* Reset all counters */
207         set_l2_indirect_reg(L2PMCR, L2PMCR_RESET_ALL);
208         set_l2_indirect_reg(L2PMCNTENCLR, l2_counter_present_mask);
209         set_l2_indirect_reg(L2PMINTENCLR, l2_counter_present_mask);
210         set_l2_indirect_reg(L2PMOVSCLR, l2_counter_present_mask);
211 }
212
213 static inline void cluster_pmu_enable(void)
214 {
215         set_l2_indirect_reg(L2PMCR, L2PMCR_COUNTERS_ENABLE);
216 }
217
218 static inline void cluster_pmu_disable(void)
219 {
220         set_l2_indirect_reg(L2PMCR, L2PMCR_COUNTERS_DISABLE);
221 }
222
223 static inline void cluster_pmu_counter_set_value(u32 idx, u64 value)
224 {
225         if (idx == l2_cycle_ctr_idx)
226                 set_l2_indirect_reg(L2PMCCNTR, value);
227         else
228                 set_l2_indirect_reg(reg_idx(IA_L2PMXEVCNTR, idx), value);
229 }
230
231 static inline u64 cluster_pmu_counter_get_value(u32 idx)
232 {
233         u64 value;
234
235         if (idx == l2_cycle_ctr_idx)
236                 value = get_l2_indirect_reg(L2PMCCNTR);
237         else
238                 value = get_l2_indirect_reg(reg_idx(IA_L2PMXEVCNTR, idx));
239
240         return value;
241 }
242
243 static inline void cluster_pmu_counter_enable(u32 idx)
244 {
245         set_l2_indirect_reg(L2PMCNTENSET, idx_to_reg_bit(idx));
246 }
247
248 static inline void cluster_pmu_counter_disable(u32 idx)
249 {
250         set_l2_indirect_reg(L2PMCNTENCLR, idx_to_reg_bit(idx));
251 }
252
253 static inline void cluster_pmu_counter_enable_interrupt(u32 idx)
254 {
255         set_l2_indirect_reg(L2PMINTENSET, idx_to_reg_bit(idx));
256 }
257
258 static inline void cluster_pmu_counter_disable_interrupt(u32 idx)
259 {
260         set_l2_indirect_reg(L2PMINTENCLR, idx_to_reg_bit(idx));
261 }
262
263 static inline void cluster_pmu_set_evccntcr(u32 val)
264 {
265         set_l2_indirect_reg(L2PMCCNTCR, val);
266 }
267
268 static inline void cluster_pmu_set_evcntcr(u32 ctr, u32 val)
269 {
270         set_l2_indirect_reg(reg_idx(IA_L2PMXEVCNTCR, ctr), val);
271 }
272
273 static inline void cluster_pmu_set_evtyper(u32 ctr, u32 val)
274 {
275         set_l2_indirect_reg(reg_idx(IA_L2PMXEVTYPER, ctr), val);
276 }
277
278 static void cluster_pmu_set_resr(struct cluster_pmu *cluster,
279                                u32 event_group, u32 event_cc)
280 {
281         u64 field;
282         u64 resr_val;
283         u32 shift;
284         unsigned long flags;
285
286         shift = L2PMRESR_GROUP_BITS * event_group;
287         field = ((u64)(event_cc & L2PMRESR_GROUP_MASK) << shift);
288
289         spin_lock_irqsave(&cluster->pmu_lock, flags);
290
291         resr_val = get_l2_indirect_reg(L2PMRESR);
292         resr_val &= ~(L2PMRESR_GROUP_MASK << shift);
293         resr_val |= field;
294         resr_val |= L2PMRESR_EN;
295         set_l2_indirect_reg(L2PMRESR, resr_val);
296
297         spin_unlock_irqrestore(&cluster->pmu_lock, flags);
298 }
299
300 /*
301  * Hardware allows filtering of events based on the originating
302  * CPU. Turn this off by setting filter bits to allow events from
303  * all CPUS, subunits and ID independent events in this cluster.
304  */
305 static inline void cluster_pmu_set_evfilter_sys_mode(u32 ctr)
306 {
307         u32 val =  L2PMXEVFILTER_SUFILTER_ALL |
308                    L2PMXEVFILTER_ORGFILTER_IDINDEP |
309                    L2PMXEVFILTER_ORGFILTER_ALL;
310
311         set_l2_indirect_reg(reg_idx(IA_L2PMXEVFILTER, ctr), val);
312 }
313
314 static inline u32 cluster_pmu_getreset_ovsr(void)
315 {
316         u32 result = get_l2_indirect_reg(L2PMOVSSET);
317
318         set_l2_indirect_reg(L2PMOVSCLR, result);
319         return result;
320 }
321
322 static inline bool cluster_pmu_has_overflowed(u32 ovsr)
323 {
324         return !!(ovsr & l2_counter_present_mask);
325 }
326
327 static inline bool cluster_pmu_counter_has_overflowed(u32 ovsr, u32 idx)
328 {
329         return !!(ovsr & idx_to_reg_bit(idx));
330 }
331
332 static void l2_cache_event_update(struct perf_event *event)
333 {
334         struct hw_perf_event *hwc = &event->hw;
335         u64 delta, prev, now;
336         u32 idx = hwc->idx;
337
338         do {
339                 prev = local64_read(&hwc->prev_count);
340                 now = cluster_pmu_counter_get_value(idx);
341         } while (local64_cmpxchg(&hwc->prev_count, prev, now) != prev);
342
343         /*
344          * The cycle counter is 64-bit, but all other counters are
345          * 32-bit, and we must handle 32-bit overflow explicitly.
346          */
347         delta = now - prev;
348         if (idx != l2_cycle_ctr_idx)
349                 delta &= 0xffffffff;
350
351         local64_add(delta, &event->count);
352 }
353
354 static void l2_cache_cluster_set_period(struct cluster_pmu *cluster,
355                                        struct hw_perf_event *hwc)
356 {
357         u32 idx = hwc->idx;
358         u64 new;
359
360         /*
361          * We limit the max period to half the max counter value so
362          * that even in the case of extreme interrupt latency the
363          * counter will (hopefully) not wrap past its initial value.
364          */
365         if (idx == l2_cycle_ctr_idx)
366                 new = L2_CYCLE_COUNTER_RELOAD;
367         else
368                 new = L2_COUNTER_RELOAD;
369
370         local64_set(&hwc->prev_count, new);
371         cluster_pmu_counter_set_value(idx, new);
372 }
373
374 static int l2_cache_get_event_idx(struct cluster_pmu *cluster,
375                                    struct perf_event *event)
376 {
377         struct hw_perf_event *hwc = &event->hw;
378         int idx;
379         int num_ctrs = cluster->l2cache_pmu->num_counters - 1;
380         unsigned int group;
381
382         if (hwc->config_base == L2CYCLE_CTR_RAW_CODE) {
383                 if (test_and_set_bit(l2_cycle_ctr_idx, cluster->used_counters))
384                         return -EAGAIN;
385
386                 return l2_cycle_ctr_idx;
387         }
388
389         idx = find_first_zero_bit(cluster->used_counters, num_ctrs);
390         if (idx == num_ctrs)
391                 /* The counters are all in use. */
392                 return -EAGAIN;
393
394         /*
395          * Check for column exclusion: event column already in use by another
396          * event. This is for events which are not in the same group.
397          * Conflicting events in the same group are detected in event_init.
398          */
399         group = L2_EVT_GROUP(hwc->config_base);
400         if (test_bit(group, cluster->used_groups))
401                 return -EAGAIN;
402
403         set_bit(idx, cluster->used_counters);
404         set_bit(group, cluster->used_groups);
405
406         return idx;
407 }
408
409 static void l2_cache_clear_event_idx(struct cluster_pmu *cluster,
410                                       struct perf_event *event)
411 {
412         struct hw_perf_event *hwc = &event->hw;
413         int idx = hwc->idx;
414
415         clear_bit(idx, cluster->used_counters);
416         if (hwc->config_base != L2CYCLE_CTR_RAW_CODE)
417                 clear_bit(L2_EVT_GROUP(hwc->config_base), cluster->used_groups);
418 }
419
420 static irqreturn_t l2_cache_handle_irq(int irq_num, void *data)
421 {
422         struct cluster_pmu *cluster = data;
423         int num_counters = cluster->l2cache_pmu->num_counters;
424         u32 ovsr;
425         int idx;
426
427         ovsr = cluster_pmu_getreset_ovsr();
428         if (!cluster_pmu_has_overflowed(ovsr))
429                 return IRQ_NONE;
430
431         for_each_set_bit(idx, cluster->used_counters, num_counters) {
432                 struct perf_event *event = cluster->events[idx];
433                 struct hw_perf_event *hwc;
434
435                 if (WARN_ON_ONCE(!event))
436                         continue;
437
438                 if (!cluster_pmu_counter_has_overflowed(ovsr, idx))
439                         continue;
440
441                 l2_cache_event_update(event);
442                 hwc = &event->hw;
443
444                 l2_cache_cluster_set_period(cluster, hwc);
445         }
446
447         return IRQ_HANDLED;
448 }
449
450 /*
451  * Implementation of abstract pmu functionality required by
452  * the core perf events code.
453  */
454
455 static void l2_cache_pmu_enable(struct pmu *pmu)
456 {
457         /*
458          * Although there is only one PMU (per socket) controlling multiple
459          * physical PMUs (per cluster), because we do not support per-task mode
460          * each event is associated with a CPU. Each event has pmu_enable
461          * called on its CPU, so here it is only necessary to enable the
462          * counters for the current CPU.
463          */
464
465         cluster_pmu_enable();
466 }
467
468 static void l2_cache_pmu_disable(struct pmu *pmu)
469 {
470         cluster_pmu_disable();
471 }
472
473 static int l2_cache_event_init(struct perf_event *event)
474 {
475         struct hw_perf_event *hwc = &event->hw;
476         struct cluster_pmu *cluster;
477         struct perf_event *sibling;
478         struct l2cache_pmu *l2cache_pmu;
479
480         if (event->attr.type != event->pmu->type)
481                 return -ENOENT;
482
483         l2cache_pmu = to_l2cache_pmu(event->pmu);
484
485         if (hwc->sample_period) {
486                 dev_dbg_ratelimited(&l2cache_pmu->pdev->dev,
487                                     "Sampling not supported\n");
488                 return -EOPNOTSUPP;
489         }
490
491         if (event->cpu < 0) {
492                 dev_dbg_ratelimited(&l2cache_pmu->pdev->dev,
493                                     "Per-task mode not supported\n");
494                 return -EOPNOTSUPP;
495         }
496
497         /* We cannot filter accurately so we just don't allow it. */
498         if (event->attr.exclude_user || event->attr.exclude_kernel ||
499             event->attr.exclude_hv || event->attr.exclude_idle) {
500                 dev_dbg_ratelimited(&l2cache_pmu->pdev->dev,
501                                     "Can't exclude execution levels\n");
502                 return -EOPNOTSUPP;
503         }
504
505         if (((L2_EVT_GROUP(event->attr.config) > L2_EVT_GROUP_MAX) ||
506              ((event->attr.config & ~L2_EVT_MASK) != 0)) &&
507             (event->attr.config != L2CYCLE_CTR_RAW_CODE)) {
508                 dev_dbg_ratelimited(&l2cache_pmu->pdev->dev,
509                                     "Invalid config %llx\n",
510                                     event->attr.config);
511                 return -EINVAL;
512         }
513
514         /* Don't allow groups with mixed PMUs, except for s/w events */
515         if (event->group_leader->pmu != event->pmu &&
516             !is_software_event(event->group_leader)) {
517                 dev_dbg_ratelimited(&l2cache_pmu->pdev->dev,
518                          "Can't create mixed PMU group\n");
519                 return -EINVAL;
520         }
521
522         list_for_each_entry(sibling, &event->group_leader->sibling_list,
523                             group_entry)
524                 if (sibling->pmu != event->pmu &&
525                     !is_software_event(sibling)) {
526                         dev_dbg_ratelimited(&l2cache_pmu->pdev->dev,
527                                  "Can't create mixed PMU group\n");
528                         return -EINVAL;
529                 }
530
531         cluster = get_cluster_pmu(l2cache_pmu, event->cpu);
532         if (!cluster) {
533                 /* CPU has not been initialised */
534                 dev_dbg_ratelimited(&l2cache_pmu->pdev->dev,
535                         "CPU%d not associated with L2 cluster\n", event->cpu);
536                 return -EINVAL;
537         }
538
539         /* Ensure all events in a group are on the same cpu */
540         if ((event->group_leader != event) &&
541             (cluster->on_cpu != event->group_leader->cpu)) {
542                 dev_dbg_ratelimited(&l2cache_pmu->pdev->dev,
543                          "Can't create group on CPUs %d and %d",
544                          event->cpu, event->group_leader->cpu);
545                 return -EINVAL;
546         }
547
548         if ((event != event->group_leader) &&
549             !is_software_event(event->group_leader) &&
550             (L2_EVT_GROUP(event->group_leader->attr.config) ==
551              L2_EVT_GROUP(event->attr.config))) {
552                 dev_dbg_ratelimited(&l2cache_pmu->pdev->dev,
553                          "Column exclusion: conflicting events %llx %llx\n",
554                        event->group_leader->attr.config,
555                        event->attr.config);
556                 return -EINVAL;
557         }
558
559         list_for_each_entry(sibling, &event->group_leader->sibling_list,
560                             group_entry) {
561                 if ((sibling != event) &&
562                     !is_software_event(sibling) &&
563                     (L2_EVT_GROUP(sibling->attr.config) ==
564                      L2_EVT_GROUP(event->attr.config))) {
565                         dev_dbg_ratelimited(&l2cache_pmu->pdev->dev,
566                              "Column exclusion: conflicting events %llx %llx\n",
567                                             sibling->attr.config,
568                                             event->attr.config);
569                         return -EINVAL;
570                 }
571         }
572
573         hwc->idx = -1;
574         hwc->config_base = event->attr.config;
575
576         /*
577          * Ensure all events are on the same cpu so all events are in the
578          * same cpu context, to avoid races on pmu_enable etc.
579          */
580         event->cpu = cluster->on_cpu;
581
582         return 0;
583 }
584
585 static void l2_cache_event_start(struct perf_event *event, int flags)
586 {
587         struct cluster_pmu *cluster;
588         struct hw_perf_event *hwc = &event->hw;
589         int idx = hwc->idx;
590         u32 config;
591         u32 event_cc, event_group;
592
593         hwc->state = 0;
594
595         cluster = get_cluster_pmu(to_l2cache_pmu(event->pmu), event->cpu);
596
597         l2_cache_cluster_set_period(cluster, hwc);
598
599         if (hwc->config_base == L2CYCLE_CTR_RAW_CODE) {
600                 cluster_pmu_set_evccntcr(0);
601         } else {
602                 config = hwc->config_base;
603                 event_cc    = L2_EVT_CODE(config);
604                 event_group = L2_EVT_GROUP(config);
605
606                 cluster_pmu_set_evcntcr(idx, 0);
607                 cluster_pmu_set_evtyper(idx, event_group);
608                 cluster_pmu_set_resr(cluster, event_group, event_cc);
609                 cluster_pmu_set_evfilter_sys_mode(idx);
610         }
611
612         cluster_pmu_counter_enable_interrupt(idx);
613         cluster_pmu_counter_enable(idx);
614 }
615
616 static void l2_cache_event_stop(struct perf_event *event, int flags)
617 {
618         struct hw_perf_event *hwc = &event->hw;
619         int idx = hwc->idx;
620
621         if (hwc->state & PERF_HES_STOPPED)
622                 return;
623
624         cluster_pmu_counter_disable_interrupt(idx);
625         cluster_pmu_counter_disable(idx);
626
627         if (flags & PERF_EF_UPDATE)
628                 l2_cache_event_update(event);
629         hwc->state |= PERF_HES_STOPPED | PERF_HES_UPTODATE;
630 }
631
632 static int l2_cache_event_add(struct perf_event *event, int flags)
633 {
634         struct hw_perf_event *hwc = &event->hw;
635         int idx;
636         int err = 0;
637         struct cluster_pmu *cluster;
638
639         cluster = get_cluster_pmu(to_l2cache_pmu(event->pmu), event->cpu);
640
641         idx = l2_cache_get_event_idx(cluster, event);
642         if (idx < 0)
643                 return idx;
644
645         hwc->idx = idx;
646         hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
647         cluster->events[idx] = event;
648         local64_set(&hwc->prev_count, 0);
649
650         if (flags & PERF_EF_START)
651                 l2_cache_event_start(event, flags);
652
653         /* Propagate changes to the userspace mapping. */
654         perf_event_update_userpage(event);
655
656         return err;
657 }
658
659 static void l2_cache_event_del(struct perf_event *event, int flags)
660 {
661         struct hw_perf_event *hwc = &event->hw;
662         struct cluster_pmu *cluster;
663         int idx = hwc->idx;
664
665         cluster = get_cluster_pmu(to_l2cache_pmu(event->pmu), event->cpu);
666
667         l2_cache_event_stop(event, flags | PERF_EF_UPDATE);
668         cluster->events[idx] = NULL;
669         l2_cache_clear_event_idx(cluster, event);
670
671         perf_event_update_userpage(event);
672 }
673
674 static void l2_cache_event_read(struct perf_event *event)
675 {
676         l2_cache_event_update(event);
677 }
678
679 static ssize_t l2_cache_pmu_cpumask_show(struct device *dev,
680                                          struct device_attribute *attr,
681                                          char *buf)
682 {
683         struct l2cache_pmu *l2cache_pmu = to_l2cache_pmu(dev_get_drvdata(dev));
684
685         return cpumap_print_to_pagebuf(true, buf, &l2cache_pmu->cpumask);
686 }
687
688 static struct device_attribute l2_cache_pmu_cpumask_attr =
689                 __ATTR(cpumask, S_IRUGO, l2_cache_pmu_cpumask_show, NULL);
690
691 static struct attribute *l2_cache_pmu_cpumask_attrs[] = {
692         &l2_cache_pmu_cpumask_attr.attr,
693         NULL,
694 };
695
696 static struct attribute_group l2_cache_pmu_cpumask_group = {
697         .attrs = l2_cache_pmu_cpumask_attrs,
698 };
699
700 /* CCG format for perf RAW codes. */
701 PMU_FORMAT_ATTR(l2_code,   "config:4-11");
702 PMU_FORMAT_ATTR(l2_group,  "config:0-3");
703 static struct attribute *l2_cache_pmu_formats[] = {
704         &format_attr_l2_code.attr,
705         &format_attr_l2_group.attr,
706         NULL,
707 };
708
709 static struct attribute_group l2_cache_pmu_format_group = {
710         .name = "format",
711         .attrs = l2_cache_pmu_formats,
712 };
713
714 static const struct attribute_group *l2_cache_pmu_attr_grps[] = {
715         &l2_cache_pmu_format_group,
716         &l2_cache_pmu_cpumask_group,
717         NULL,
718 };
719
720 /*
721  * Generic device handlers
722  */
723
724 static const struct acpi_device_id l2_cache_pmu_acpi_match[] = {
725         { "QCOM8130", },
726         { }
727 };
728
729 static int get_num_counters(void)
730 {
731         int val;
732
733         val = get_l2_indirect_reg(L2PMCR);
734
735         /*
736          * Read number of counters from L2PMCR and add 1
737          * for the cycle counter.
738          */
739         return ((val >> L2PMCR_NUM_EV_SHIFT) & L2PMCR_NUM_EV_MASK) + 1;
740 }
741
742 static struct cluster_pmu *l2_cache_associate_cpu_with_cluster(
743         struct l2cache_pmu *l2cache_pmu, int cpu)
744 {
745         u64 mpidr;
746         int cpu_cluster_id;
747         struct cluster_pmu *cluster = NULL;
748
749         /*
750          * This assumes that the cluster_id is in MPIDR[aff1] for
751          * single-threaded cores, and MPIDR[aff2] for multi-threaded
752          * cores. This logic will have to be updated if this changes.
753          */
754         mpidr = read_cpuid_mpidr();
755         if (mpidr & MPIDR_MT_BITMASK)
756                 cpu_cluster_id = MPIDR_AFFINITY_LEVEL(mpidr, 2);
757         else
758                 cpu_cluster_id = MPIDR_AFFINITY_LEVEL(mpidr, 1);
759
760         list_for_each_entry(cluster, &l2cache_pmu->clusters, next) {
761                 if (cluster->cluster_id != cpu_cluster_id)
762                         continue;
763
764                 dev_info(&l2cache_pmu->pdev->dev,
765                          "CPU%d associated with cluster %d\n", cpu,
766                          cluster->cluster_id);
767                 cpumask_set_cpu(cpu, &cluster->cluster_cpus);
768                 *per_cpu_ptr(l2cache_pmu->pmu_cluster, cpu) = cluster;
769                 break;
770         }
771
772         return cluster;
773 }
774
775 static int l2cache_pmu_online_cpu(unsigned int cpu, struct hlist_node *node)
776 {
777         struct cluster_pmu *cluster;
778         struct l2cache_pmu *l2cache_pmu;
779
780         l2cache_pmu = hlist_entry_safe(node, struct l2cache_pmu, node);
781         cluster = get_cluster_pmu(l2cache_pmu, cpu);
782         if (!cluster) {
783                 /* First time this CPU has come online */
784                 cluster = l2_cache_associate_cpu_with_cluster(l2cache_pmu, cpu);
785                 if (!cluster) {
786                         /* Only if broken firmware doesn't list every cluster */
787                         WARN_ONCE(1, "No L2 cache cluster for CPU%d\n", cpu);
788                         return 0;
789                 }
790         }
791
792         /* If another CPU is managing this cluster, we're done */
793         if (cluster->on_cpu != -1)
794                 return 0;
795
796         /*
797          * All CPUs on this cluster were down, use this one.
798          * Reset to put it into sane state.
799          */
800         cluster->on_cpu = cpu;
801         cpumask_set_cpu(cpu, &l2cache_pmu->cpumask);
802         cluster_pmu_reset();
803
804         WARN_ON(irq_set_affinity(cluster->irq, cpumask_of(cpu)));
805         enable_irq(cluster->irq);
806
807         return 0;
808 }
809
810 static int l2cache_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
811 {
812         struct cluster_pmu *cluster;
813         struct l2cache_pmu *l2cache_pmu;
814         cpumask_t cluster_online_cpus;
815         unsigned int target;
816
817         l2cache_pmu = hlist_entry_safe(node, struct l2cache_pmu, node);
818         cluster = get_cluster_pmu(l2cache_pmu, cpu);
819         if (!cluster)
820                 return 0;
821
822         /* If this CPU is not managing the cluster, we're done */
823         if (cluster->on_cpu != cpu)
824                 return 0;
825
826         /* Give up ownership of cluster */
827         cpumask_clear_cpu(cpu, &l2cache_pmu->cpumask);
828         cluster->on_cpu = -1;
829
830         /* Any other CPU for this cluster which is still online */
831         cpumask_and(&cluster_online_cpus, &cluster->cluster_cpus,
832                     cpu_online_mask);
833         target = cpumask_any_but(&cluster_online_cpus, cpu);
834         if (target >= nr_cpu_ids) {
835                 disable_irq(cluster->irq);
836                 return 0;
837         }
838
839         perf_pmu_migrate_context(&l2cache_pmu->pmu, cpu, target);
840         cluster->on_cpu = target;
841         cpumask_set_cpu(target, &l2cache_pmu->cpumask);
842         WARN_ON(irq_set_affinity(cluster->irq, cpumask_of(target)));
843
844         return 0;
845 }
846
847 static int l2_cache_pmu_probe_cluster(struct device *dev, void *data)
848 {
849         struct platform_device *pdev = to_platform_device(dev->parent);
850         struct platform_device *sdev = to_platform_device(dev);
851         struct l2cache_pmu *l2cache_pmu = data;
852         struct cluster_pmu *cluster;
853         struct acpi_device *device;
854         unsigned long fw_cluster_id;
855         int err;
856         int irq;
857
858         if (acpi_bus_get_device(ACPI_HANDLE(dev), &device))
859                 return -ENODEV;
860
861         if (kstrtoul(device->pnp.unique_id, 10, &fw_cluster_id) < 0) {
862                 dev_err(&pdev->dev, "unable to read ACPI uid\n");
863                 return -ENODEV;
864         }
865
866         cluster = devm_kzalloc(&pdev->dev, sizeof(*cluster), GFP_KERNEL);
867         if (!cluster)
868                 return -ENOMEM;
869
870         INIT_LIST_HEAD(&cluster->next);
871         list_add(&cluster->next, &l2cache_pmu->clusters);
872         cluster->cluster_id = fw_cluster_id;
873
874         irq = platform_get_irq(sdev, 0);
875         if (irq < 0) {
876                 dev_err(&pdev->dev,
877                         "Failed to get valid irq for cluster %ld\n",
878                         fw_cluster_id);
879                 return irq;
880         }
881         irq_set_status_flags(irq, IRQ_NOAUTOEN);
882         cluster->irq = irq;
883
884         cluster->l2cache_pmu = l2cache_pmu;
885         cluster->on_cpu = -1;
886
887         err = devm_request_irq(&pdev->dev, irq, l2_cache_handle_irq,
888                                IRQF_NOBALANCING | IRQF_NO_THREAD,
889                                "l2-cache-pmu", cluster);
890         if (err) {
891                 dev_err(&pdev->dev,
892                         "Unable to request IRQ%d for L2 PMU counters\n", irq);
893                 return err;
894         }
895
896         dev_info(&pdev->dev,
897                 "Registered L2 cache PMU cluster %ld\n", fw_cluster_id);
898
899         spin_lock_init(&cluster->pmu_lock);
900
901         l2cache_pmu->num_pmus++;
902
903         return 0;
904 }
905
906 static int l2_cache_pmu_probe(struct platform_device *pdev)
907 {
908         int err;
909         struct l2cache_pmu *l2cache_pmu;
910
911         l2cache_pmu =
912                 devm_kzalloc(&pdev->dev, sizeof(*l2cache_pmu), GFP_KERNEL);
913         if (!l2cache_pmu)
914                 return -ENOMEM;
915
916         INIT_LIST_HEAD(&l2cache_pmu->clusters);
917
918         platform_set_drvdata(pdev, l2cache_pmu);
919         l2cache_pmu->pmu = (struct pmu) {
920                 /* suffix is instance id for future use with multiple sockets */
921                 .name           = "l2cache_0",
922                 .task_ctx_nr    = perf_invalid_context,
923                 .pmu_enable     = l2_cache_pmu_enable,
924                 .pmu_disable    = l2_cache_pmu_disable,
925                 .event_init     = l2_cache_event_init,
926                 .add            = l2_cache_event_add,
927                 .del            = l2_cache_event_del,
928                 .start          = l2_cache_event_start,
929                 .stop           = l2_cache_event_stop,
930                 .read           = l2_cache_event_read,
931                 .attr_groups    = l2_cache_pmu_attr_grps,
932         };
933
934         l2cache_pmu->num_counters = get_num_counters();
935         l2cache_pmu->pdev = pdev;
936         l2cache_pmu->pmu_cluster = devm_alloc_percpu(&pdev->dev,
937                                                      struct cluster_pmu *);
938         if (!l2cache_pmu->pmu_cluster)
939                 return -ENOMEM;
940
941         l2_cycle_ctr_idx = l2cache_pmu->num_counters - 1;
942         l2_counter_present_mask = GENMASK(l2cache_pmu->num_counters - 2, 0) |
943                 BIT(L2CYCLE_CTR_BIT);
944
945         cpumask_clear(&l2cache_pmu->cpumask);
946
947         /* Read cluster info and initialize each cluster */
948         err = device_for_each_child(&pdev->dev, l2cache_pmu,
949                                     l2_cache_pmu_probe_cluster);
950         if (err)
951                 return err;
952
953         if (l2cache_pmu->num_pmus == 0) {
954                 dev_err(&pdev->dev, "No hardware L2 cache PMUs found\n");
955                 return -ENODEV;
956         }
957
958         err = cpuhp_state_add_instance(CPUHP_AP_PERF_ARM_QCOM_L2_ONLINE,
959                                        &l2cache_pmu->node);
960         if (err) {
961                 dev_err(&pdev->dev, "Error %d registering hotplug", err);
962                 return err;
963         }
964
965         err = perf_pmu_register(&l2cache_pmu->pmu, l2cache_pmu->pmu.name, -1);
966         if (err) {
967                 dev_err(&pdev->dev, "Error %d registering L2 cache PMU\n", err);
968                 goto out_unregister;
969         }
970
971         dev_info(&pdev->dev, "Registered L2 cache PMU using %d HW PMUs\n",
972                  l2cache_pmu->num_pmus);
973
974         return err;
975
976 out_unregister:
977         cpuhp_state_remove_instance(CPUHP_AP_PERF_ARM_QCOM_L2_ONLINE,
978                                     &l2cache_pmu->node);
979         return err;
980 }
981
982 static int l2_cache_pmu_remove(struct platform_device *pdev)
983 {
984         struct l2cache_pmu *l2cache_pmu =
985                 to_l2cache_pmu(platform_get_drvdata(pdev));
986
987         perf_pmu_unregister(&l2cache_pmu->pmu);
988         cpuhp_state_remove_instance(CPUHP_AP_PERF_ARM_QCOM_L2_ONLINE,
989                                     &l2cache_pmu->node);
990         return 0;
991 }
992
993 static struct platform_driver l2_cache_pmu_driver = {
994         .driver = {
995                 .name = "qcom-l2cache-pmu",
996                 .acpi_match_table = ACPI_PTR(l2_cache_pmu_acpi_match),
997         },
998         .probe = l2_cache_pmu_probe,
999         .remove = l2_cache_pmu_remove,
1000 };
1001
1002 static int __init register_l2_cache_pmu_driver(void)
1003 {
1004         int err;
1005
1006         err = cpuhp_setup_state_multi(CPUHP_AP_PERF_ARM_QCOM_L2_ONLINE,
1007                                       "AP_PERF_ARM_QCOM_L2_ONLINE",
1008                                       l2cache_pmu_online_cpu,
1009                                       l2cache_pmu_offline_cpu);
1010         if (err)
1011                 return err;
1012
1013         return platform_driver_register(&l2_cache_pmu_driver);
1014 }
1015 device_initcall(register_l2_cache_pmu_driver);