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9#include <linux/interrupt.h>
10#include <linux/irqdomain.h>
11#include <linux/module.h>
12#include <linux/of.h>
13#include <linux/perf_event.h>
14#include <linux/platform_device.h>
15
16#include <asm/processor.h>
17#include <asm/stacktrace.h>
18
19
20#define XTENSA_PMU_PMG 0x1000
21
22#define XTENSA_PMU_PM(i) (0x1080 + (i) * 4)
23
24#define XTENSA_PMU_PMCTRL(i) (0x1100 + (i) * 4)
25
26#define XTENSA_PMU_PMSTAT(i) (0x1180 + (i) * 4)
27
28#define XTENSA_PMU_PMG_PMEN 0x1
29
30#define XTENSA_PMU_COUNTER_MASK 0xffffffffULL
31#define XTENSA_PMU_COUNTER_MAX 0x7fffffff
32
33#define XTENSA_PMU_PMCTRL_INTEN 0x00000001
34#define XTENSA_PMU_PMCTRL_KRNLCNT 0x00000008
35#define XTENSA_PMU_PMCTRL_TRACELEVEL 0x000000f0
36#define XTENSA_PMU_PMCTRL_SELECT_SHIFT 8
37#define XTENSA_PMU_PMCTRL_SELECT 0x00001f00
38#define XTENSA_PMU_PMCTRL_MASK_SHIFT 16
39#define XTENSA_PMU_PMCTRL_MASK 0xffff0000
40
41#define XTENSA_PMU_MASK(select, mask) \
42 (((select) << XTENSA_PMU_PMCTRL_SELECT_SHIFT) | \
43 ((mask) << XTENSA_PMU_PMCTRL_MASK_SHIFT) | \
44 XTENSA_PMU_PMCTRL_TRACELEVEL | \
45 XTENSA_PMU_PMCTRL_INTEN)
46
47#define XTENSA_PMU_PMSTAT_OVFL 0x00000001
48#define XTENSA_PMU_PMSTAT_INTASRT 0x00000010
49
50struct xtensa_pmu_events {
51
52 struct perf_event *event[XCHAL_NUM_PERF_COUNTERS];
53
54 unsigned long used_mask[BITS_TO_LONGS(XCHAL_NUM_PERF_COUNTERS)];
55};
56static DEFINE_PER_CPU(struct xtensa_pmu_events, xtensa_pmu_events);
57
58static const u32 xtensa_hw_ctl[] = {
59 [PERF_COUNT_HW_CPU_CYCLES] = XTENSA_PMU_MASK(0, 0x1),
60 [PERF_COUNT_HW_INSTRUCTIONS] = XTENSA_PMU_MASK(2, 0xffff),
61 [PERF_COUNT_HW_CACHE_REFERENCES] = XTENSA_PMU_MASK(10, 0x1),
62 [PERF_COUNT_HW_CACHE_MISSES] = XTENSA_PMU_MASK(12, 0x1),
63
64 [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = XTENSA_PMU_MASK(2, 0x490),
65
66 [PERF_COUNT_HW_STALLED_CYCLES_FRONTEND] = XTENSA_PMU_MASK(4, 0x1ff),
67
68 [PERF_COUNT_HW_STALLED_CYCLES_BACKEND] = XTENSA_PMU_MASK(3, 0x1ff),
69};
70
71#define C(_x) PERF_COUNT_HW_CACHE_##_x
72
73static const u32 xtensa_cache_ctl[][C(OP_MAX)][C(RESULT_MAX)] = {
74 [C(L1D)] = {
75 [C(OP_READ)] = {
76 [C(RESULT_ACCESS)] = XTENSA_PMU_MASK(10, 0x1),
77 [C(RESULT_MISS)] = XTENSA_PMU_MASK(10, 0x2),
78 },
79 [C(OP_WRITE)] = {
80 [C(RESULT_ACCESS)] = XTENSA_PMU_MASK(11, 0x1),
81 [C(RESULT_MISS)] = XTENSA_PMU_MASK(11, 0x2),
82 },
83 },
84 [C(L1I)] = {
85 [C(OP_READ)] = {
86 [C(RESULT_ACCESS)] = XTENSA_PMU_MASK(8, 0x1),
87 [C(RESULT_MISS)] = XTENSA_PMU_MASK(8, 0x2),
88 },
89 },
90 [C(DTLB)] = {
91 [C(OP_READ)] = {
92 [C(RESULT_ACCESS)] = XTENSA_PMU_MASK(9, 0x1),
93 [C(RESULT_MISS)] = XTENSA_PMU_MASK(9, 0x8),
94 },
95 },
96 [C(ITLB)] = {
97 [C(OP_READ)] = {
98 [C(RESULT_ACCESS)] = XTENSA_PMU_MASK(7, 0x1),
99 [C(RESULT_MISS)] = XTENSA_PMU_MASK(7, 0x8),
100 },
101 },
102};
103
104static int xtensa_pmu_cache_event(u64 config)
105{
106 unsigned int cache_type, cache_op, cache_result;
107 int ret;
108
109 cache_type = (config >> 0) & 0xff;
110 cache_op = (config >> 8) & 0xff;
111 cache_result = (config >> 16) & 0xff;
112
113 if (cache_type >= ARRAY_SIZE(xtensa_cache_ctl) ||
114 cache_op >= C(OP_MAX) ||
115 cache_result >= C(RESULT_MAX))
116 return -EINVAL;
117
118 ret = xtensa_cache_ctl[cache_type][cache_op][cache_result];
119
120 if (ret == 0)
121 return -EINVAL;
122
123 return ret;
124}
125
126static inline uint32_t xtensa_pmu_read_counter(int idx)
127{
128 return get_er(XTENSA_PMU_PM(idx));
129}
130
131static inline void xtensa_pmu_write_counter(int idx, uint32_t v)
132{
133 set_er(v, XTENSA_PMU_PM(idx));
134}
135
136static void xtensa_perf_event_update(struct perf_event *event,
137 struct hw_perf_event *hwc, int idx)
138{
139 uint64_t prev_raw_count, new_raw_count;
140 int64_t delta;
141
142 do {
143 prev_raw_count = local64_read(&hwc->prev_count);
144 new_raw_count = xtensa_pmu_read_counter(event->hw.idx);
145 } while (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
146 new_raw_count) != prev_raw_count);
147
148 delta = (new_raw_count - prev_raw_count) & XTENSA_PMU_COUNTER_MASK;
149
150 local64_add(delta, &event->count);
151 local64_sub(delta, &hwc->period_left);
152}
153
154static bool xtensa_perf_event_set_period(struct perf_event *event,
155 struct hw_perf_event *hwc, int idx)
156{
157 bool rc = false;
158 s64 left;
159
160 if (!is_sampling_event(event)) {
161 left = XTENSA_PMU_COUNTER_MAX;
162 } else {
163 s64 period = hwc->sample_period;
164
165 left = local64_read(&hwc->period_left);
166 if (left <= -period) {
167 left = period;
168 local64_set(&hwc->period_left, left);
169 hwc->last_period = period;
170 rc = true;
171 } else if (left <= 0) {
172 left += period;
173 local64_set(&hwc->period_left, left);
174 hwc->last_period = period;
175 rc = true;
176 }
177 if (left > XTENSA_PMU_COUNTER_MAX)
178 left = XTENSA_PMU_COUNTER_MAX;
179 }
180
181 local64_set(&hwc->prev_count, -left);
182 xtensa_pmu_write_counter(idx, -left);
183 perf_event_update_userpage(event);
184
185 return rc;
186}
187
188static void xtensa_pmu_enable(struct pmu *pmu)
189{
190 set_er(get_er(XTENSA_PMU_PMG) | XTENSA_PMU_PMG_PMEN, XTENSA_PMU_PMG);
191}
192
193static void xtensa_pmu_disable(struct pmu *pmu)
194{
195 set_er(get_er(XTENSA_PMU_PMG) & ~XTENSA_PMU_PMG_PMEN, XTENSA_PMU_PMG);
196}
197
198static int xtensa_pmu_event_init(struct perf_event *event)
199{
200 int ret;
201
202 switch (event->attr.type) {
203 case PERF_TYPE_HARDWARE:
204 if (event->attr.config >= ARRAY_SIZE(xtensa_hw_ctl) ||
205 xtensa_hw_ctl[event->attr.config] == 0)
206 return -EINVAL;
207 event->hw.config = xtensa_hw_ctl[event->attr.config];
208 return 0;
209
210 case PERF_TYPE_HW_CACHE:
211 ret = xtensa_pmu_cache_event(event->attr.config);
212 if (ret < 0)
213 return ret;
214 event->hw.config = ret;
215 return 0;
216
217 case PERF_TYPE_RAW:
218
219 if ((event->attr.config & XTENSA_PMU_PMCTRL_SELECT) ==
220 (1 << XTENSA_PMU_PMCTRL_SELECT_SHIFT))
221 return -EINVAL;
222 event->hw.config = (event->attr.config &
223 (XTENSA_PMU_PMCTRL_KRNLCNT |
224 XTENSA_PMU_PMCTRL_TRACELEVEL |
225 XTENSA_PMU_PMCTRL_SELECT |
226 XTENSA_PMU_PMCTRL_MASK)) |
227 XTENSA_PMU_PMCTRL_INTEN;
228 return 0;
229
230 default:
231 return -ENOENT;
232 }
233}
234
235
236
237
238
239
240static void xtensa_pmu_start(struct perf_event *event, int flags)
241{
242 struct hw_perf_event *hwc = &event->hw;
243 int idx = hwc->idx;
244
245 if (WARN_ON_ONCE(idx == -1))
246 return;
247
248 if (flags & PERF_EF_RELOAD) {
249 WARN_ON_ONCE(!(event->hw.state & PERF_HES_UPTODATE));
250 xtensa_perf_event_set_period(event, hwc, idx);
251 }
252
253 hwc->state = 0;
254
255 set_er(hwc->config, XTENSA_PMU_PMCTRL(idx));
256}
257
258static void xtensa_pmu_stop(struct perf_event *event, int flags)
259{
260 struct hw_perf_event *hwc = &event->hw;
261 int idx = hwc->idx;
262
263 if (!(hwc->state & PERF_HES_STOPPED)) {
264 set_er(0, XTENSA_PMU_PMCTRL(idx));
265 set_er(get_er(XTENSA_PMU_PMSTAT(idx)),
266 XTENSA_PMU_PMSTAT(idx));
267 hwc->state |= PERF_HES_STOPPED;
268 }
269
270 if ((flags & PERF_EF_UPDATE) &&
271 !(event->hw.state & PERF_HES_UPTODATE)) {
272 xtensa_perf_event_update(event, &event->hw, idx);
273 event->hw.state |= PERF_HES_UPTODATE;
274 }
275}
276
277
278
279
280
281static int xtensa_pmu_add(struct perf_event *event, int flags)
282{
283 struct xtensa_pmu_events *ev = this_cpu_ptr(&xtensa_pmu_events);
284 struct hw_perf_event *hwc = &event->hw;
285 int idx = hwc->idx;
286
287 if (__test_and_set_bit(idx, ev->used_mask)) {
288 idx = find_first_zero_bit(ev->used_mask,
289 XCHAL_NUM_PERF_COUNTERS);
290 if (idx == XCHAL_NUM_PERF_COUNTERS)
291 return -EAGAIN;
292
293 __set_bit(idx, ev->used_mask);
294 hwc->idx = idx;
295 }
296 ev->event[idx] = event;
297
298 hwc->state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
299
300 if (flags & PERF_EF_START)
301 xtensa_pmu_start(event, PERF_EF_RELOAD);
302
303 perf_event_update_userpage(event);
304 return 0;
305}
306
307static void xtensa_pmu_del(struct perf_event *event, int flags)
308{
309 struct xtensa_pmu_events *ev = this_cpu_ptr(&xtensa_pmu_events);
310
311 xtensa_pmu_stop(event, PERF_EF_UPDATE);
312 __clear_bit(event->hw.idx, ev->used_mask);
313 perf_event_update_userpage(event);
314}
315
316static void xtensa_pmu_read(struct perf_event *event)
317{
318 xtensa_perf_event_update(event, &event->hw, event->hw.idx);
319}
320
321static int callchain_trace(struct stackframe *frame, void *data)
322{
323 struct perf_callchain_entry_ctx *entry = data;
324
325 perf_callchain_store(entry, frame->pc);
326 return 0;
327}
328
329void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry,
330 struct pt_regs *regs)
331{
332 xtensa_backtrace_kernel(regs, entry->max_stack,
333 callchain_trace, NULL, entry);
334}
335
336void perf_callchain_user(struct perf_callchain_entry_ctx *entry,
337 struct pt_regs *regs)
338{
339 xtensa_backtrace_user(regs, entry->max_stack,
340 callchain_trace, entry);
341}
342
343void perf_event_print_debug(void)
344{
345 unsigned long flags;
346 unsigned i;
347
348 local_irq_save(flags);
349 pr_info("CPU#%d: PMG: 0x%08lx\n", smp_processor_id(),
350 get_er(XTENSA_PMU_PMG));
351 for (i = 0; i < XCHAL_NUM_PERF_COUNTERS; ++i)
352 pr_info("PM%d: 0x%08lx, PMCTRL%d: 0x%08lx, PMSTAT%d: 0x%08lx\n",
353 i, get_er(XTENSA_PMU_PM(i)),
354 i, get_er(XTENSA_PMU_PMCTRL(i)),
355 i, get_er(XTENSA_PMU_PMSTAT(i)));
356 local_irq_restore(flags);
357}
358
359irqreturn_t xtensa_pmu_irq_handler(int irq, void *dev_id)
360{
361 irqreturn_t rc = IRQ_NONE;
362 struct xtensa_pmu_events *ev = this_cpu_ptr(&xtensa_pmu_events);
363 unsigned i;
364
365 for_each_set_bit(i, ev->used_mask, XCHAL_NUM_PERF_COUNTERS) {
366 uint32_t v = get_er(XTENSA_PMU_PMSTAT(i));
367 struct perf_event *event = ev->event[i];
368 struct hw_perf_event *hwc = &event->hw;
369 u64 last_period;
370
371 if (!(v & XTENSA_PMU_PMSTAT_OVFL))
372 continue;
373
374 set_er(v, XTENSA_PMU_PMSTAT(i));
375 xtensa_perf_event_update(event, hwc, i);
376 last_period = hwc->last_period;
377 if (xtensa_perf_event_set_period(event, hwc, i)) {
378 struct perf_sample_data data;
379 struct pt_regs *regs = get_irq_regs();
380
381 perf_sample_data_init(&data, 0, last_period);
382 if (perf_event_overflow(event, &data, regs))
383 xtensa_pmu_stop(event, 0);
384 }
385
386 rc = IRQ_HANDLED;
387 }
388 return rc;
389}
390
391static struct pmu xtensa_pmu = {
392 .pmu_enable = xtensa_pmu_enable,
393 .pmu_disable = xtensa_pmu_disable,
394 .event_init = xtensa_pmu_event_init,
395 .add = xtensa_pmu_add,
396 .del = xtensa_pmu_del,
397 .start = xtensa_pmu_start,
398 .stop = xtensa_pmu_stop,
399 .read = xtensa_pmu_read,
400};
401
402static int xtensa_pmu_setup(unsigned int cpu)
403{
404 unsigned i;
405
406 set_er(0, XTENSA_PMU_PMG);
407 for (i = 0; i < XCHAL_NUM_PERF_COUNTERS; ++i) {
408 set_er(0, XTENSA_PMU_PMCTRL(i));
409 set_er(get_er(XTENSA_PMU_PMSTAT(i)), XTENSA_PMU_PMSTAT(i));
410 }
411 return 0;
412}
413
414static int __init xtensa_pmu_init(void)
415{
416 int ret;
417 int irq = irq_create_mapping(NULL, XCHAL_PROFILING_INTERRUPT);
418
419 ret = cpuhp_setup_state(CPUHP_AP_PERF_XTENSA_STARTING,
420 "perf/xtensa:starting", xtensa_pmu_setup,
421 NULL);
422 if (ret) {
423 pr_err("xtensa_pmu: failed to register CPU-hotplug.\n");
424 return ret;
425 }
426#if XTENSA_FAKE_NMI
427 enable_irq(irq);
428#else
429 ret = request_irq(irq, xtensa_pmu_irq_handler, IRQF_PERCPU,
430 "pmu", NULL);
431 if (ret < 0)
432 return ret;
433#endif
434
435 ret = perf_pmu_register(&xtensa_pmu, "cpu", PERF_TYPE_RAW);
436 if (ret)
437 free_irq(irq, NULL);
438
439 return ret;
440}
441early_initcall(xtensa_pmu_init);
442
