xref: /linux/arch/sparc/kernel/perf_event.c (revision 913df4453f85f1fe79b35ecf3c9a0c0b707d22a2)
1 /* Performance event support for sparc64.
2  *
3  * Copyright (C) 2009 David S. Miller <davem@davemloft.net>
4  *
5  * This code is based almost entirely upon the x86 perf event
6  * code, which is:
7  *
8  *  Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de>
9  *  Copyright (C) 2008-2009 Red Hat, Inc., Ingo Molnar
10  *  Copyright (C) 2009 Jaswinder Singh Rajput
11  *  Copyright (C) 2009 Advanced Micro Devices, Inc., Robert Richter
12  *  Copyright (C) 2008-2009 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
13  */
14 
15 #include <linux/perf_event.h>
16 #include <linux/kprobes.h>
17 #include <linux/kernel.h>
18 #include <linux/kdebug.h>
19 #include <linux/mutex.h>
20 
21 #include <asm/cpudata.h>
22 #include <asm/atomic.h>
23 #include <asm/nmi.h>
24 #include <asm/pcr.h>
25 
26 /* Sparc64 chips have two performance counters, 32-bits each, with
27  * overflow interrupts generated on transition from 0xffffffff to 0.
28  * The counters are accessed in one go using a 64-bit register.
29  *
30  * Both counters are controlled using a single control register.  The
31  * only way to stop all sampling is to clear all of the context (user,
32  * supervisor, hypervisor) sampling enable bits.  But these bits apply
33  * to both counters, thus the two counters can't be enabled/disabled
34  * individually.
35  *
36  * The control register has two event fields, one for each of the two
37  * counters.  It's thus nearly impossible to have one counter going
38  * while keeping the other one stopped.  Therefore it is possible to
39  * get overflow interrupts for counters not currently "in use" and
40  * that condition must be checked in the overflow interrupt handler.
41  *
42  * So we use a hack, in that we program inactive counters with the
43  * "sw_count0" and "sw_count1" events.  These count how many times
44  * the instruction "sethi %hi(0xfc000), %g0" is executed.  It's an
45  * unusual way to encode a NOP and therefore will not trigger in
46  * normal code.
47  */
48 
49 #define MAX_HWEVENTS			2
50 #define MAX_PERIOD			((1UL << 32) - 1)
51 
52 #define PIC_UPPER_INDEX			0
53 #define PIC_LOWER_INDEX			1
54 
55 struct cpu_hw_events {
56 	struct perf_event	*events[MAX_HWEVENTS];
57 	unsigned long		used_mask[BITS_TO_LONGS(MAX_HWEVENTS)];
58 	unsigned long		active_mask[BITS_TO_LONGS(MAX_HWEVENTS)];
59 	u64			pcr;
60 	int			enabled;
61 };
62 DEFINE_PER_CPU(struct cpu_hw_events, cpu_hw_events) = { .enabled = 1, };
63 
64 struct perf_event_map {
65 	u16	encoding;
66 	u8	pic_mask;
67 #define PIC_NONE	0x00
68 #define PIC_UPPER	0x01
69 #define PIC_LOWER	0x02
70 };
71 
72 static unsigned long perf_event_encode(const struct perf_event_map *pmap)
73 {
74 	return ((unsigned long) pmap->encoding << 16) | pmap->pic_mask;
75 }
76 
77 static void perf_event_decode(unsigned long val, u16 *enc, u8 *msk)
78 {
79 	*msk = val & 0xff;
80 	*enc = val >> 16;
81 }
82 
83 #define C(x) PERF_COUNT_HW_CACHE_##x
84 
85 #define CACHE_OP_UNSUPPORTED	0xfffe
86 #define CACHE_OP_NONSENSE	0xffff
87 
88 typedef struct perf_event_map cache_map_t
89 				[PERF_COUNT_HW_CACHE_MAX]
90 				[PERF_COUNT_HW_CACHE_OP_MAX]
91 				[PERF_COUNT_HW_CACHE_RESULT_MAX];
92 
93 struct sparc_pmu {
94 	const struct perf_event_map	*(*event_map)(int);
95 	const cache_map_t		*cache_map;
96 	int				max_events;
97 	int				upper_shift;
98 	int				lower_shift;
99 	int				event_mask;
100 	int				hv_bit;
101 	int				irq_bit;
102 	int				upper_nop;
103 	int				lower_nop;
104 };
105 
106 static const struct perf_event_map ultra3_perfmon_event_map[] = {
107 	[PERF_COUNT_HW_CPU_CYCLES] = { 0x0000, PIC_UPPER | PIC_LOWER },
108 	[PERF_COUNT_HW_INSTRUCTIONS] = { 0x0001, PIC_UPPER | PIC_LOWER },
109 	[PERF_COUNT_HW_CACHE_REFERENCES] = { 0x0009, PIC_LOWER },
110 	[PERF_COUNT_HW_CACHE_MISSES] = { 0x0009, PIC_UPPER },
111 };
112 
113 static const struct perf_event_map *ultra3_event_map(int event_id)
114 {
115 	return &ultra3_perfmon_event_map[event_id];
116 }
117 
118 static const cache_map_t ultra3_cache_map = {
119 [C(L1D)] = {
120 	[C(OP_READ)] = {
121 		[C(RESULT_ACCESS)] = { 0x09, PIC_LOWER, },
122 		[C(RESULT_MISS)] = { 0x09, PIC_UPPER, },
123 	},
124 	[C(OP_WRITE)] = {
125 		[C(RESULT_ACCESS)] = { 0x0a, PIC_LOWER },
126 		[C(RESULT_MISS)] = { 0x0a, PIC_UPPER },
127 	},
128 	[C(OP_PREFETCH)] = {
129 		[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
130 		[C(RESULT_MISS)] = { CACHE_OP_UNSUPPORTED },
131 	},
132 },
133 [C(L1I)] = {
134 	[C(OP_READ)] = {
135 		[C(RESULT_ACCESS)] = { 0x09, PIC_LOWER, },
136 		[C(RESULT_MISS)] = { 0x09, PIC_UPPER, },
137 	},
138 	[ C(OP_WRITE) ] = {
139 		[ C(RESULT_ACCESS) ] = { CACHE_OP_NONSENSE },
140 		[ C(RESULT_MISS)   ] = { CACHE_OP_NONSENSE },
141 	},
142 	[ C(OP_PREFETCH) ] = {
143 		[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
144 		[ C(RESULT_MISS)   ] = { CACHE_OP_UNSUPPORTED },
145 	},
146 },
147 [C(LL)] = {
148 	[C(OP_READ)] = {
149 		[C(RESULT_ACCESS)] = { 0x0c, PIC_LOWER, },
150 		[C(RESULT_MISS)] = { 0x0c, PIC_UPPER, },
151 	},
152 	[C(OP_WRITE)] = {
153 		[C(RESULT_ACCESS)] = { 0x0c, PIC_LOWER },
154 		[C(RESULT_MISS)] = { 0x0c, PIC_UPPER },
155 	},
156 	[C(OP_PREFETCH)] = {
157 		[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
158 		[C(RESULT_MISS)] = { CACHE_OP_UNSUPPORTED },
159 	},
160 },
161 [C(DTLB)] = {
162 	[C(OP_READ)] = {
163 		[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
164 		[C(RESULT_MISS)] = { 0x12, PIC_UPPER, },
165 	},
166 	[ C(OP_WRITE) ] = {
167 		[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
168 		[ C(RESULT_MISS)   ] = { CACHE_OP_UNSUPPORTED },
169 	},
170 	[ C(OP_PREFETCH) ] = {
171 		[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
172 		[ C(RESULT_MISS)   ] = { CACHE_OP_UNSUPPORTED },
173 	},
174 },
175 [C(ITLB)] = {
176 	[C(OP_READ)] = {
177 		[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
178 		[C(RESULT_MISS)] = { 0x11, PIC_UPPER, },
179 	},
180 	[ C(OP_WRITE) ] = {
181 		[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
182 		[ C(RESULT_MISS)   ] = { CACHE_OP_UNSUPPORTED },
183 	},
184 	[ C(OP_PREFETCH) ] = {
185 		[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
186 		[ C(RESULT_MISS)   ] = { CACHE_OP_UNSUPPORTED },
187 	},
188 },
189 [C(BPU)] = {
190 	[C(OP_READ)] = {
191 		[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
192 		[C(RESULT_MISS)] = { CACHE_OP_UNSUPPORTED },
193 	},
194 	[ C(OP_WRITE) ] = {
195 		[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
196 		[ C(RESULT_MISS)   ] = { CACHE_OP_UNSUPPORTED },
197 	},
198 	[ C(OP_PREFETCH) ] = {
199 		[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
200 		[ C(RESULT_MISS)   ] = { CACHE_OP_UNSUPPORTED },
201 	},
202 },
203 };
204 
205 static const struct sparc_pmu ultra3_pmu = {
206 	.event_map	= ultra3_event_map,
207 	.cache_map	= &ultra3_cache_map,
208 	.max_events	= ARRAY_SIZE(ultra3_perfmon_event_map),
209 	.upper_shift	= 11,
210 	.lower_shift	= 4,
211 	.event_mask	= 0x3f,
212 	.upper_nop	= 0x1c,
213 	.lower_nop	= 0x14,
214 };
215 
216 /* Niagara1 is very limited.  The upper PIC is hard-locked to count
217  * only instructions, so it is free running which creates all kinds of
218  * problems.  Some hardware designs make one wonder if the creator
219  * even looked at how this stuff gets used by software.
220  */
221 static const struct perf_event_map niagara1_perfmon_event_map[] = {
222 	[PERF_COUNT_HW_CPU_CYCLES] = { 0x00, PIC_UPPER },
223 	[PERF_COUNT_HW_INSTRUCTIONS] = { 0x00, PIC_UPPER },
224 	[PERF_COUNT_HW_CACHE_REFERENCES] = { 0, PIC_NONE },
225 	[PERF_COUNT_HW_CACHE_MISSES] = { 0x03, PIC_LOWER },
226 };
227 
228 static const struct perf_event_map *niagara1_event_map(int event_id)
229 {
230 	return &niagara1_perfmon_event_map[event_id];
231 }
232 
233 static const cache_map_t niagara1_cache_map = {
234 [C(L1D)] = {
235 	[C(OP_READ)] = {
236 		[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
237 		[C(RESULT_MISS)] = { 0x03, PIC_LOWER, },
238 	},
239 	[C(OP_WRITE)] = {
240 		[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
241 		[C(RESULT_MISS)] = { 0x03, PIC_LOWER, },
242 	},
243 	[C(OP_PREFETCH)] = {
244 		[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
245 		[C(RESULT_MISS)] = { CACHE_OP_UNSUPPORTED },
246 	},
247 },
248 [C(L1I)] = {
249 	[C(OP_READ)] = {
250 		[C(RESULT_ACCESS)] = { 0x00, PIC_UPPER },
251 		[C(RESULT_MISS)] = { 0x02, PIC_LOWER, },
252 	},
253 	[ C(OP_WRITE) ] = {
254 		[ C(RESULT_ACCESS) ] = { CACHE_OP_NONSENSE },
255 		[ C(RESULT_MISS)   ] = { CACHE_OP_NONSENSE },
256 	},
257 	[ C(OP_PREFETCH) ] = {
258 		[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
259 		[ C(RESULT_MISS)   ] = { CACHE_OP_UNSUPPORTED },
260 	},
261 },
262 [C(LL)] = {
263 	[C(OP_READ)] = {
264 		[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
265 		[C(RESULT_MISS)] = { 0x07, PIC_LOWER, },
266 	},
267 	[C(OP_WRITE)] = {
268 		[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
269 		[C(RESULT_MISS)] = { 0x07, PIC_LOWER, },
270 	},
271 	[C(OP_PREFETCH)] = {
272 		[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
273 		[C(RESULT_MISS)] = { CACHE_OP_UNSUPPORTED },
274 	},
275 },
276 [C(DTLB)] = {
277 	[C(OP_READ)] = {
278 		[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
279 		[C(RESULT_MISS)] = { 0x05, PIC_LOWER, },
280 	},
281 	[ C(OP_WRITE) ] = {
282 		[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
283 		[ C(RESULT_MISS)   ] = { CACHE_OP_UNSUPPORTED },
284 	},
285 	[ C(OP_PREFETCH) ] = {
286 		[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
287 		[ C(RESULT_MISS)   ] = { CACHE_OP_UNSUPPORTED },
288 	},
289 },
290 [C(ITLB)] = {
291 	[C(OP_READ)] = {
292 		[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
293 		[C(RESULT_MISS)] = { 0x04, PIC_LOWER, },
294 	},
295 	[ C(OP_WRITE) ] = {
296 		[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
297 		[ C(RESULT_MISS)   ] = { CACHE_OP_UNSUPPORTED },
298 	},
299 	[ C(OP_PREFETCH) ] = {
300 		[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
301 		[ C(RESULT_MISS)   ] = { CACHE_OP_UNSUPPORTED },
302 	},
303 },
304 [C(BPU)] = {
305 	[C(OP_READ)] = {
306 		[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
307 		[C(RESULT_MISS)] = { CACHE_OP_UNSUPPORTED },
308 	},
309 	[ C(OP_WRITE) ] = {
310 		[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
311 		[ C(RESULT_MISS)   ] = { CACHE_OP_UNSUPPORTED },
312 	},
313 	[ C(OP_PREFETCH) ] = {
314 		[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
315 		[ C(RESULT_MISS)   ] = { CACHE_OP_UNSUPPORTED },
316 	},
317 },
318 };
319 
320 static const struct sparc_pmu niagara1_pmu = {
321 	.event_map	= niagara1_event_map,
322 	.cache_map	= &niagara1_cache_map,
323 	.max_events	= ARRAY_SIZE(niagara1_perfmon_event_map),
324 	.upper_shift	= 0,
325 	.lower_shift	= 4,
326 	.event_mask	= 0x7,
327 	.upper_nop	= 0x0,
328 	.lower_nop	= 0x0,
329 };
330 
331 static const struct perf_event_map niagara2_perfmon_event_map[] = {
332 	[PERF_COUNT_HW_CPU_CYCLES] = { 0x02ff, PIC_UPPER | PIC_LOWER },
333 	[PERF_COUNT_HW_INSTRUCTIONS] = { 0x02ff, PIC_UPPER | PIC_LOWER },
334 	[PERF_COUNT_HW_CACHE_REFERENCES] = { 0x0208, PIC_UPPER | PIC_LOWER },
335 	[PERF_COUNT_HW_CACHE_MISSES] = { 0x0302, PIC_UPPER | PIC_LOWER },
336 	[PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = { 0x0201, PIC_UPPER | PIC_LOWER },
337 	[PERF_COUNT_HW_BRANCH_MISSES] = { 0x0202, PIC_UPPER | PIC_LOWER },
338 };
339 
340 static const struct perf_event_map *niagara2_event_map(int event_id)
341 {
342 	return &niagara2_perfmon_event_map[event_id];
343 }
344 
345 static const cache_map_t niagara2_cache_map = {
346 [C(L1D)] = {
347 	[C(OP_READ)] = {
348 		[C(RESULT_ACCESS)] = { 0x0208, PIC_UPPER | PIC_LOWER, },
349 		[C(RESULT_MISS)] = { 0x0302, PIC_UPPER | PIC_LOWER, },
350 	},
351 	[C(OP_WRITE)] = {
352 		[C(RESULT_ACCESS)] = { 0x0210, PIC_UPPER | PIC_LOWER, },
353 		[C(RESULT_MISS)] = { 0x0302, PIC_UPPER | PIC_LOWER, },
354 	},
355 	[C(OP_PREFETCH)] = {
356 		[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
357 		[C(RESULT_MISS)] = { CACHE_OP_UNSUPPORTED },
358 	},
359 },
360 [C(L1I)] = {
361 	[C(OP_READ)] = {
362 		[C(RESULT_ACCESS)] = { 0x02ff, PIC_UPPER | PIC_LOWER, },
363 		[C(RESULT_MISS)] = { 0x0301, PIC_UPPER | PIC_LOWER, },
364 	},
365 	[ C(OP_WRITE) ] = {
366 		[ C(RESULT_ACCESS) ] = { CACHE_OP_NONSENSE },
367 		[ C(RESULT_MISS)   ] = { CACHE_OP_NONSENSE },
368 	},
369 	[ C(OP_PREFETCH) ] = {
370 		[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
371 		[ C(RESULT_MISS)   ] = { CACHE_OP_UNSUPPORTED },
372 	},
373 },
374 [C(LL)] = {
375 	[C(OP_READ)] = {
376 		[C(RESULT_ACCESS)] = { 0x0208, PIC_UPPER | PIC_LOWER, },
377 		[C(RESULT_MISS)] = { 0x0330, PIC_UPPER | PIC_LOWER, },
378 	},
379 	[C(OP_WRITE)] = {
380 		[C(RESULT_ACCESS)] = { 0x0210, PIC_UPPER | PIC_LOWER, },
381 		[C(RESULT_MISS)] = { 0x0320, PIC_UPPER | PIC_LOWER, },
382 	},
383 	[C(OP_PREFETCH)] = {
384 		[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
385 		[C(RESULT_MISS)] = { CACHE_OP_UNSUPPORTED },
386 	},
387 },
388 [C(DTLB)] = {
389 	[C(OP_READ)] = {
390 		[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
391 		[C(RESULT_MISS)] = { 0x0b08, PIC_UPPER | PIC_LOWER, },
392 	},
393 	[ C(OP_WRITE) ] = {
394 		[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
395 		[ C(RESULT_MISS)   ] = { CACHE_OP_UNSUPPORTED },
396 	},
397 	[ C(OP_PREFETCH) ] = {
398 		[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
399 		[ C(RESULT_MISS)   ] = { CACHE_OP_UNSUPPORTED },
400 	},
401 },
402 [C(ITLB)] = {
403 	[C(OP_READ)] = {
404 		[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
405 		[C(RESULT_MISS)] = { 0xb04, PIC_UPPER | PIC_LOWER, },
406 	},
407 	[ C(OP_WRITE) ] = {
408 		[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
409 		[ C(RESULT_MISS)   ] = { CACHE_OP_UNSUPPORTED },
410 	},
411 	[ C(OP_PREFETCH) ] = {
412 		[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
413 		[ C(RESULT_MISS)   ] = { CACHE_OP_UNSUPPORTED },
414 	},
415 },
416 [C(BPU)] = {
417 	[C(OP_READ)] = {
418 		[C(RESULT_ACCESS)] = { CACHE_OP_UNSUPPORTED },
419 		[C(RESULT_MISS)] = { CACHE_OP_UNSUPPORTED },
420 	},
421 	[ C(OP_WRITE) ] = {
422 		[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
423 		[ C(RESULT_MISS)   ] = { CACHE_OP_UNSUPPORTED },
424 	},
425 	[ C(OP_PREFETCH) ] = {
426 		[ C(RESULT_ACCESS) ] = { CACHE_OP_UNSUPPORTED },
427 		[ C(RESULT_MISS)   ] = { CACHE_OP_UNSUPPORTED },
428 	},
429 },
430 };
431 
432 static const struct sparc_pmu niagara2_pmu = {
433 	.event_map	= niagara2_event_map,
434 	.cache_map	= &niagara2_cache_map,
435 	.max_events	= ARRAY_SIZE(niagara2_perfmon_event_map),
436 	.upper_shift	= 19,
437 	.lower_shift	= 6,
438 	.event_mask	= 0xfff,
439 	.hv_bit		= 0x8,
440 	.irq_bit	= 0x03,
441 	.upper_nop	= 0x220,
442 	.lower_nop	= 0x220,
443 };
444 
445 static const struct sparc_pmu *sparc_pmu __read_mostly;
446 
447 static u64 event_encoding(u64 event_id, int idx)
448 {
449 	if (idx == PIC_UPPER_INDEX)
450 		event_id <<= sparc_pmu->upper_shift;
451 	else
452 		event_id <<= sparc_pmu->lower_shift;
453 	return event_id;
454 }
455 
456 static u64 mask_for_index(int idx)
457 {
458 	return event_encoding(sparc_pmu->event_mask, idx);
459 }
460 
461 static u64 nop_for_index(int idx)
462 {
463 	return event_encoding(idx == PIC_UPPER_INDEX ?
464 			      sparc_pmu->upper_nop :
465 			      sparc_pmu->lower_nop, idx);
466 }
467 
468 static inline void sparc_pmu_enable_event(struct cpu_hw_events *cpuc, struct hw_perf_event *hwc, int idx)
469 {
470 	u64 val, mask = mask_for_index(idx);
471 
472 	val = cpuc->pcr;
473 	val &= ~mask;
474 	val |= hwc->config;
475 	cpuc->pcr = val;
476 
477 	pcr_ops->write(cpuc->pcr);
478 }
479 
480 static inline void sparc_pmu_disable_event(struct cpu_hw_events *cpuc, struct hw_perf_event *hwc, int idx)
481 {
482 	u64 mask = mask_for_index(idx);
483 	u64 nop = nop_for_index(idx);
484 	u64 val;
485 
486 	val = cpuc->pcr;
487 	val &= ~mask;
488 	val |= nop;
489 	cpuc->pcr = val;
490 
491 	pcr_ops->write(cpuc->pcr);
492 }
493 
494 void hw_perf_enable(void)
495 {
496 	struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
497 	u64 val;
498 	int i;
499 
500 	if (cpuc->enabled)
501 		return;
502 
503 	cpuc->enabled = 1;
504 	barrier();
505 
506 	val = cpuc->pcr;
507 
508 	for (i = 0; i < MAX_HWEVENTS; i++) {
509 		struct perf_event *cp = cpuc->events[i];
510 		struct hw_perf_event *hwc;
511 
512 		if (!cp)
513 			continue;
514 		hwc = &cp->hw;
515 		val |= hwc->config_base;
516 	}
517 
518 	cpuc->pcr = val;
519 
520 	pcr_ops->write(cpuc->pcr);
521 }
522 
523 void hw_perf_disable(void)
524 {
525 	struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
526 	u64 val;
527 
528 	if (!cpuc->enabled)
529 		return;
530 
531 	cpuc->enabled = 0;
532 
533 	val = cpuc->pcr;
534 	val &= ~(PCR_UTRACE | PCR_STRACE |
535 		 sparc_pmu->hv_bit | sparc_pmu->irq_bit);
536 	cpuc->pcr = val;
537 
538 	pcr_ops->write(cpuc->pcr);
539 }
540 
541 static u32 read_pmc(int idx)
542 {
543 	u64 val;
544 
545 	read_pic(val);
546 	if (idx == PIC_UPPER_INDEX)
547 		val >>= 32;
548 
549 	return val & 0xffffffff;
550 }
551 
552 static void write_pmc(int idx, u64 val)
553 {
554 	u64 shift, mask, pic;
555 
556 	shift = 0;
557 	if (idx == PIC_UPPER_INDEX)
558 		shift = 32;
559 
560 	mask = ((u64) 0xffffffff) << shift;
561 	val <<= shift;
562 
563 	read_pic(pic);
564 	pic &= ~mask;
565 	pic |= val;
566 	write_pic(pic);
567 }
568 
569 static int sparc_perf_event_set_period(struct perf_event *event,
570 				       struct hw_perf_event *hwc, int idx)
571 {
572 	s64 left = atomic64_read(&hwc->period_left);
573 	s64 period = hwc->sample_period;
574 	int ret = 0;
575 
576 	if (unlikely(left <= -period)) {
577 		left = period;
578 		atomic64_set(&hwc->period_left, left);
579 		hwc->last_period = period;
580 		ret = 1;
581 	}
582 
583 	if (unlikely(left <= 0)) {
584 		left += period;
585 		atomic64_set(&hwc->period_left, left);
586 		hwc->last_period = period;
587 		ret = 1;
588 	}
589 	if (left > MAX_PERIOD)
590 		left = MAX_PERIOD;
591 
592 	atomic64_set(&hwc->prev_count, (u64)-left);
593 
594 	write_pmc(idx, (u64)(-left) & 0xffffffff);
595 
596 	perf_event_update_userpage(event);
597 
598 	return ret;
599 }
600 
601 static int sparc_pmu_enable(struct perf_event *event)
602 {
603 	struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
604 	struct hw_perf_event *hwc = &event->hw;
605 	int idx = hwc->idx;
606 
607 	if (test_and_set_bit(idx, cpuc->used_mask))
608 		return -EAGAIN;
609 
610 	sparc_pmu_disable_event(cpuc, hwc, idx);
611 
612 	cpuc->events[idx] = event;
613 	set_bit(idx, cpuc->active_mask);
614 
615 	sparc_perf_event_set_period(event, hwc, idx);
616 	sparc_pmu_enable_event(cpuc, hwc, idx);
617 	perf_event_update_userpage(event);
618 	return 0;
619 }
620 
621 static u64 sparc_perf_event_update(struct perf_event *event,
622 				   struct hw_perf_event *hwc, int idx)
623 {
624 	int shift = 64 - 32;
625 	u64 prev_raw_count, new_raw_count;
626 	s64 delta;
627 
628 again:
629 	prev_raw_count = atomic64_read(&hwc->prev_count);
630 	new_raw_count = read_pmc(idx);
631 
632 	if (atomic64_cmpxchg(&hwc->prev_count, prev_raw_count,
633 			     new_raw_count) != prev_raw_count)
634 		goto again;
635 
636 	delta = (new_raw_count << shift) - (prev_raw_count << shift);
637 	delta >>= shift;
638 
639 	atomic64_add(delta, &event->count);
640 	atomic64_sub(delta, &hwc->period_left);
641 
642 	return new_raw_count;
643 }
644 
645 static void sparc_pmu_disable(struct perf_event *event)
646 {
647 	struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
648 	struct hw_perf_event *hwc = &event->hw;
649 	int idx = hwc->idx;
650 
651 	clear_bit(idx, cpuc->active_mask);
652 	sparc_pmu_disable_event(cpuc, hwc, idx);
653 
654 	barrier();
655 
656 	sparc_perf_event_update(event, hwc, idx);
657 	cpuc->events[idx] = NULL;
658 	clear_bit(idx, cpuc->used_mask);
659 
660 	perf_event_update_userpage(event);
661 }
662 
663 static void sparc_pmu_read(struct perf_event *event)
664 {
665 	struct hw_perf_event *hwc = &event->hw;
666 
667 	sparc_perf_event_update(event, hwc, hwc->idx);
668 }
669 
670 static void sparc_pmu_unthrottle(struct perf_event *event)
671 {
672 	struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
673 	struct hw_perf_event *hwc = &event->hw;
674 
675 	sparc_pmu_enable_event(cpuc, hwc, hwc->idx);
676 }
677 
678 static atomic_t active_events = ATOMIC_INIT(0);
679 static DEFINE_MUTEX(pmc_grab_mutex);
680 
681 static void perf_stop_nmi_watchdog(void *unused)
682 {
683 	struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
684 
685 	stop_nmi_watchdog(NULL);
686 	cpuc->pcr = pcr_ops->read();
687 }
688 
689 void perf_event_grab_pmc(void)
690 {
691 	if (atomic_inc_not_zero(&active_events))
692 		return;
693 
694 	mutex_lock(&pmc_grab_mutex);
695 	if (atomic_read(&active_events) == 0) {
696 		if (atomic_read(&nmi_active) > 0) {
697 			on_each_cpu(perf_stop_nmi_watchdog, NULL, 1);
698 			BUG_ON(atomic_read(&nmi_active) != 0);
699 		}
700 		atomic_inc(&active_events);
701 	}
702 	mutex_unlock(&pmc_grab_mutex);
703 }
704 
705 void perf_event_release_pmc(void)
706 {
707 	if (atomic_dec_and_mutex_lock(&active_events, &pmc_grab_mutex)) {
708 		if (atomic_read(&nmi_active) == 0)
709 			on_each_cpu(start_nmi_watchdog, NULL, 1);
710 		mutex_unlock(&pmc_grab_mutex);
711 	}
712 }
713 
714 static const struct perf_event_map *sparc_map_cache_event(u64 config)
715 {
716 	unsigned int cache_type, cache_op, cache_result;
717 	const struct perf_event_map *pmap;
718 
719 	if (!sparc_pmu->cache_map)
720 		return ERR_PTR(-ENOENT);
721 
722 	cache_type = (config >>  0) & 0xff;
723 	if (cache_type >= PERF_COUNT_HW_CACHE_MAX)
724 		return ERR_PTR(-EINVAL);
725 
726 	cache_op = (config >>  8) & 0xff;
727 	if (cache_op >= PERF_COUNT_HW_CACHE_OP_MAX)
728 		return ERR_PTR(-EINVAL);
729 
730 	cache_result = (config >> 16) & 0xff;
731 	if (cache_result >= PERF_COUNT_HW_CACHE_RESULT_MAX)
732 		return ERR_PTR(-EINVAL);
733 
734 	pmap = &((*sparc_pmu->cache_map)[cache_type][cache_op][cache_result]);
735 
736 	if (pmap->encoding == CACHE_OP_UNSUPPORTED)
737 		return ERR_PTR(-ENOENT);
738 
739 	if (pmap->encoding == CACHE_OP_NONSENSE)
740 		return ERR_PTR(-EINVAL);
741 
742 	return pmap;
743 }
744 
745 static void hw_perf_event_destroy(struct perf_event *event)
746 {
747 	perf_event_release_pmc();
748 }
749 
750 /* Make sure all events can be scheduled into the hardware at
751  * the same time.  This is simplified by the fact that we only
752  * need to support 2 simultaneous HW events.
753  */
754 static int sparc_check_constraints(unsigned long *events, int n_ev)
755 {
756 	if (n_ev <= perf_max_events) {
757 		u8 msk1, msk2;
758 		u16 dummy;
759 
760 		if (n_ev == 1)
761 			return 0;
762 		BUG_ON(n_ev != 2);
763 		perf_event_decode(events[0], &dummy, &msk1);
764 		perf_event_decode(events[1], &dummy, &msk2);
765 
766 		/* If both events can go on any counter, OK.  */
767 		if (msk1 == (PIC_UPPER | PIC_LOWER) &&
768 		    msk2 == (PIC_UPPER | PIC_LOWER))
769 			return 0;
770 
771 		/* If one event is limited to a specific counter,
772 		 * and the other can go on both, OK.
773 		 */
774 		if ((msk1 == PIC_UPPER || msk1 == PIC_LOWER) &&
775 		    msk2 == (PIC_UPPER | PIC_LOWER))
776 			return 0;
777 		if ((msk2 == PIC_UPPER || msk2 == PIC_LOWER) &&
778 		    msk1 == (PIC_UPPER | PIC_LOWER))
779 			return 0;
780 
781 		/* If the events are fixed to different counters, OK.  */
782 		if ((msk1 == PIC_UPPER && msk2 == PIC_LOWER) ||
783 		    (msk1 == PIC_LOWER && msk2 == PIC_UPPER))
784 			return 0;
785 
786 		/* Otherwise, there is a conflict.  */
787 	}
788 
789 	return -1;
790 }
791 
792 static int check_excludes(struct perf_event **evts, int n_prev, int n_new)
793 {
794 	int eu = 0, ek = 0, eh = 0;
795 	struct perf_event *event;
796 	int i, n, first;
797 
798 	n = n_prev + n_new;
799 	if (n <= 1)
800 		return 0;
801 
802 	first = 1;
803 	for (i = 0; i < n; i++) {
804 		event = evts[i];
805 		if (first) {
806 			eu = event->attr.exclude_user;
807 			ek = event->attr.exclude_kernel;
808 			eh = event->attr.exclude_hv;
809 			first = 0;
810 		} else if (event->attr.exclude_user != eu ||
811 			   event->attr.exclude_kernel != ek ||
812 			   event->attr.exclude_hv != eh) {
813 			return -EAGAIN;
814 		}
815 	}
816 
817 	return 0;
818 }
819 
820 static int collect_events(struct perf_event *group, int max_count,
821 			  struct perf_event *evts[], unsigned long *events)
822 {
823 	struct perf_event *event;
824 	int n = 0;
825 
826 	if (!is_software_event(group)) {
827 		if (n >= max_count)
828 			return -1;
829 		evts[n] = group;
830 		events[n++] = group->hw.event_base;
831 	}
832 	list_for_each_entry(event, &group->sibling_list, group_entry) {
833 		if (!is_software_event(event) &&
834 		    event->state != PERF_EVENT_STATE_OFF) {
835 			if (n >= max_count)
836 				return -1;
837 			evts[n] = event;
838 			events[n++] = event->hw.event_base;
839 		}
840 	}
841 	return n;
842 }
843 
844 static int __hw_perf_event_init(struct perf_event *event)
845 {
846 	struct perf_event_attr *attr = &event->attr;
847 	struct perf_event *evts[MAX_HWEVENTS];
848 	struct hw_perf_event *hwc = &event->hw;
849 	unsigned long events[MAX_HWEVENTS];
850 	const struct perf_event_map *pmap;
851 	u64 enc;
852 	int n;
853 
854 	if (atomic_read(&nmi_active) < 0)
855 		return -ENODEV;
856 
857 	if (attr->type == PERF_TYPE_HARDWARE) {
858 		if (attr->config >= sparc_pmu->max_events)
859 			return -EINVAL;
860 		pmap = sparc_pmu->event_map(attr->config);
861 	} else if (attr->type == PERF_TYPE_HW_CACHE) {
862 		pmap = sparc_map_cache_event(attr->config);
863 		if (IS_ERR(pmap))
864 			return PTR_ERR(pmap);
865 	} else
866 		return -EOPNOTSUPP;
867 
868 	/* We save the enable bits in the config_base.  So to
869 	 * turn off sampling just write 'config', and to enable
870 	 * things write 'config | config_base'.
871 	 */
872 	hwc->config_base = sparc_pmu->irq_bit;
873 	if (!attr->exclude_user)
874 		hwc->config_base |= PCR_UTRACE;
875 	if (!attr->exclude_kernel)
876 		hwc->config_base |= PCR_STRACE;
877 	if (!attr->exclude_hv)
878 		hwc->config_base |= sparc_pmu->hv_bit;
879 
880 	hwc->event_base = perf_event_encode(pmap);
881 
882 	enc = pmap->encoding;
883 
884 	n = 0;
885 	if (event->group_leader != event) {
886 		n = collect_events(event->group_leader,
887 				   perf_max_events - 1,
888 				   evts, events);
889 		if (n < 0)
890 			return -EINVAL;
891 	}
892 	events[n] = hwc->event_base;
893 	evts[n] = event;
894 
895 	if (check_excludes(evts, n, 1))
896 		return -EINVAL;
897 
898 	if (sparc_check_constraints(events, n + 1))
899 		return -EINVAL;
900 
901 	/* Try to do all error checking before this point, as unwinding
902 	 * state after grabbing the PMC is difficult.
903 	 */
904 	perf_event_grab_pmc();
905 	event->destroy = hw_perf_event_destroy;
906 
907 	if (!hwc->sample_period) {
908 		hwc->sample_period = MAX_PERIOD;
909 		hwc->last_period = hwc->sample_period;
910 		atomic64_set(&hwc->period_left, hwc->sample_period);
911 	}
912 
913 	if (pmap->pic_mask & PIC_UPPER) {
914 		hwc->idx = PIC_UPPER_INDEX;
915 		enc <<= sparc_pmu->upper_shift;
916 	} else {
917 		hwc->idx = PIC_LOWER_INDEX;
918 		enc <<= sparc_pmu->lower_shift;
919 	}
920 
921 	hwc->config |= enc;
922 	return 0;
923 }
924 
925 static const struct pmu pmu = {
926 	.enable		= sparc_pmu_enable,
927 	.disable	= sparc_pmu_disable,
928 	.read		= sparc_pmu_read,
929 	.unthrottle	= sparc_pmu_unthrottle,
930 };
931 
932 const struct pmu *hw_perf_event_init(struct perf_event *event)
933 {
934 	int err = __hw_perf_event_init(event);
935 
936 	if (err)
937 		return ERR_PTR(err);
938 	return &pmu;
939 }
940 
941 void perf_event_print_debug(void)
942 {
943 	unsigned long flags;
944 	u64 pcr, pic;
945 	int cpu;
946 
947 	if (!sparc_pmu)
948 		return;
949 
950 	local_irq_save(flags);
951 
952 	cpu = smp_processor_id();
953 
954 	pcr = pcr_ops->read();
955 	read_pic(pic);
956 
957 	pr_info("\n");
958 	pr_info("CPU#%d: PCR[%016llx] PIC[%016llx]\n",
959 		cpu, pcr, pic);
960 
961 	local_irq_restore(flags);
962 }
963 
964 static int __kprobes perf_event_nmi_handler(struct notifier_block *self,
965 					    unsigned long cmd, void *__args)
966 {
967 	struct die_args *args = __args;
968 	struct perf_sample_data data;
969 	struct cpu_hw_events *cpuc;
970 	struct pt_regs *regs;
971 	int idx;
972 
973 	if (!atomic_read(&active_events))
974 		return NOTIFY_DONE;
975 
976 	switch (cmd) {
977 	case DIE_NMI:
978 		break;
979 
980 	default:
981 		return NOTIFY_DONE;
982 	}
983 
984 	regs = args->regs;
985 
986 	data.addr = 0;
987 
988 	cpuc = &__get_cpu_var(cpu_hw_events);
989 	for (idx = 0; idx < MAX_HWEVENTS; idx++) {
990 		struct perf_event *event = cpuc->events[idx];
991 		struct hw_perf_event *hwc;
992 		u64 val;
993 
994 		if (!test_bit(idx, cpuc->active_mask))
995 			continue;
996 		hwc = &event->hw;
997 		val = sparc_perf_event_update(event, hwc, idx);
998 		if (val & (1ULL << 31))
999 			continue;
1000 
1001 		data.period = event->hw.last_period;
1002 		if (!sparc_perf_event_set_period(event, hwc, idx))
1003 			continue;
1004 
1005 		if (perf_event_overflow(event, 1, &data, regs))
1006 			sparc_pmu_disable_event(cpuc, hwc, idx);
1007 	}
1008 
1009 	return NOTIFY_STOP;
1010 }
1011 
1012 static __read_mostly struct notifier_block perf_event_nmi_notifier = {
1013 	.notifier_call		= perf_event_nmi_handler,
1014 };
1015 
1016 static bool __init supported_pmu(void)
1017 {
1018 	if (!strcmp(sparc_pmu_type, "ultra3") ||
1019 	    !strcmp(sparc_pmu_type, "ultra3+") ||
1020 	    !strcmp(sparc_pmu_type, "ultra3i") ||
1021 	    !strcmp(sparc_pmu_type, "ultra4+")) {
1022 		sparc_pmu = &ultra3_pmu;
1023 		return true;
1024 	}
1025 	if (!strcmp(sparc_pmu_type, "niagara")) {
1026 		sparc_pmu = &niagara1_pmu;
1027 		return true;
1028 	}
1029 	if (!strcmp(sparc_pmu_type, "niagara2")) {
1030 		sparc_pmu = &niagara2_pmu;
1031 		return true;
1032 	}
1033 	return false;
1034 }
1035 
1036 void __init init_hw_perf_events(void)
1037 {
1038 	pr_info("Performance events: ");
1039 
1040 	if (!supported_pmu()) {
1041 		pr_cont("No support for PMU type '%s'\n", sparc_pmu_type);
1042 		return;
1043 	}
1044 
1045 	pr_cont("Supported PMU type is '%s'\n", sparc_pmu_type);
1046 
1047 	/* All sparc64 PMUs currently have 2 events.  But this simple
1048 	 * driver only supports one active event at a time.
1049 	 */
1050 	perf_max_events = 1;
1051 
1052 	register_die_notifier(&perf_event_nmi_notifier);
1053 }
1054