xref: /openbmc/linux/arch/powerpc/perf/mpc7450-pmu.c (revision 9cfc5c90)
1 /*
2  * Performance counter support for MPC7450-family processors.
3  *
4  * Copyright 2008-2009 Paul Mackerras, IBM Corporation.
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License
8  * as published by the Free Software Foundation; either version
9  * 2 of the License, or (at your option) any later version.
10  */
11 #include <linux/string.h>
12 #include <linux/perf_event.h>
13 #include <asm/reg.h>
14 #include <asm/cputable.h>
15 
16 #define N_COUNTER	6	/* Number of hardware counters */
17 #define MAX_ALT		3	/* Maximum number of event alternative codes */
18 
19 /*
20  * Bits in event code for MPC7450 family
21  */
22 #define PM_THRMULT_MSKS	0x40000
23 #define PM_THRESH_SH	12
24 #define PM_THRESH_MSK	0x3f
25 #define PM_PMC_SH	8
26 #define PM_PMC_MSK	7
27 #define PM_PMCSEL_MSK	0x7f
28 
29 /*
30  * Classify events according to how specific their PMC requirements are.
31  * Result is:
32  *	0: can go on any PMC
33  *	1: can go on PMCs 1-4
34  *	2: can go on PMCs 1,2,4
35  *	3: can go on PMCs 1 or 2
36  *	4: can only go on one PMC
37  *	-1: event code is invalid
38  */
39 #define N_CLASSES	5
40 
41 static int mpc7450_classify_event(u32 event)
42 {
43 	int pmc;
44 
45 	pmc = (event >> PM_PMC_SH) & PM_PMC_MSK;
46 	if (pmc) {
47 		if (pmc > N_COUNTER)
48 			return -1;
49 		return 4;
50 	}
51 	event &= PM_PMCSEL_MSK;
52 	if (event <= 1)
53 		return 0;
54 	if (event <= 7)
55 		return 1;
56 	if (event <= 13)
57 		return 2;
58 	if (event <= 22)
59 		return 3;
60 	return -1;
61 }
62 
63 /*
64  * Events using threshold and possible threshold scale:
65  *	code	scale?	name
66  *	11e	N	PM_INSTQ_EXCEED_CYC
67  *	11f	N	PM_ALTV_IQ_EXCEED_CYC
68  *	128	Y	PM_DTLB_SEARCH_EXCEED_CYC
69  *	12b	Y	PM_LD_MISS_EXCEED_L1_CYC
70  *	220	N	PM_CQ_EXCEED_CYC
71  *	30c	N	PM_GPR_RB_EXCEED_CYC
72  *	30d	?	PM_FPR_IQ_EXCEED_CYC ?
73  *	311	Y	PM_ITLB_SEARCH_EXCEED
74  *	410	N	PM_GPR_IQ_EXCEED_CYC
75  */
76 
77 /*
78  * Return use of threshold and threshold scale bits:
79  * 0 = uses neither, 1 = uses threshold, 2 = uses both
80  */
81 static int mpc7450_threshold_use(u32 event)
82 {
83 	int pmc, sel;
84 
85 	pmc = (event >> PM_PMC_SH) & PM_PMC_MSK;
86 	sel = event & PM_PMCSEL_MSK;
87 	switch (pmc) {
88 	case 1:
89 		if (sel == 0x1e || sel == 0x1f)
90 			return 1;
91 		if (sel == 0x28 || sel == 0x2b)
92 			return 2;
93 		break;
94 	case 2:
95 		if (sel == 0x20)
96 			return 1;
97 		break;
98 	case 3:
99 		if (sel == 0xc || sel == 0xd)
100 			return 1;
101 		if (sel == 0x11)
102 			return 2;
103 		break;
104 	case 4:
105 		if (sel == 0x10)
106 			return 1;
107 		break;
108 	}
109 	return 0;
110 }
111 
112 /*
113  * Layout of constraint bits:
114  * 33222222222211111111110000000000
115  * 10987654321098765432109876543210
116  *  |<    ><  > < > < ><><><><><><>
117  *  TS TV   G4   G3  G2P6P5P4P3P2P1
118  *
119  * P1 - P6
120  *	0 - 11: Count of events needing PMC1 .. PMC6
121  *
122  * G2
123  *	12 - 14: Count of events needing PMC1 or PMC2
124  *
125  * G3
126  *	16 - 18: Count of events needing PMC1, PMC2 or PMC4
127  *
128  * G4
129  *	20 - 23: Count of events needing PMC1, PMC2, PMC3 or PMC4
130  *
131  * TV
132  *	24 - 29: Threshold value requested
133  *
134  * TS
135  *	30: Threshold scale value requested
136  */
137 
138 static u32 pmcbits[N_COUNTER][2] = {
139 	{ 0x00844002, 0x00111001 },	/* PMC1 mask, value: P1,G2,G3,G4 */
140 	{ 0x00844008, 0x00111004 },	/* PMC2: P2,G2,G3,G4 */
141 	{ 0x00800020, 0x00100010 },	/* PMC3: P3,G4 */
142 	{ 0x00840080, 0x00110040 },	/* PMC4: P4,G3,G4 */
143 	{ 0x00000200, 0x00000100 },	/* PMC5: P5 */
144 	{ 0x00000800, 0x00000400 }	/* PMC6: P6 */
145 };
146 
147 static u32 classbits[N_CLASSES - 1][2] = {
148 	{ 0x00000000, 0x00000000 },	/* class 0: no constraint */
149 	{ 0x00800000, 0x00100000 },	/* class 1: G4 */
150 	{ 0x00040000, 0x00010000 },	/* class 2: G3 */
151 	{ 0x00004000, 0x00001000 },	/* class 3: G2 */
152 };
153 
154 static int mpc7450_get_constraint(u64 event, unsigned long *maskp,
155 				  unsigned long *valp)
156 {
157 	int pmc, class;
158 	u32 mask, value;
159 	int thresh, tuse;
160 
161 	class = mpc7450_classify_event(event);
162 	if (class < 0)
163 		return -1;
164 	if (class == 4) {
165 		pmc = ((unsigned int)event >> PM_PMC_SH) & PM_PMC_MSK;
166 		mask  = pmcbits[pmc - 1][0];
167 		value = pmcbits[pmc - 1][1];
168 	} else {
169 		mask  = classbits[class][0];
170 		value = classbits[class][1];
171 	}
172 
173 	tuse = mpc7450_threshold_use(event);
174 	if (tuse) {
175 		thresh = ((unsigned int)event >> PM_THRESH_SH) & PM_THRESH_MSK;
176 		mask  |= 0x3f << 24;
177 		value |= thresh << 24;
178 		if (tuse == 2) {
179 			mask |= 0x40000000;
180 			if ((unsigned int)event & PM_THRMULT_MSKS)
181 				value |= 0x40000000;
182 		}
183 	}
184 
185 	*maskp = mask;
186 	*valp = value;
187 	return 0;
188 }
189 
190 static const unsigned int event_alternatives[][MAX_ALT] = {
191 	{ 0x217, 0x317 },		/* PM_L1_DCACHE_MISS */
192 	{ 0x418, 0x50f, 0x60f },	/* PM_SNOOP_RETRY */
193 	{ 0x502, 0x602 },		/* PM_L2_HIT */
194 	{ 0x503, 0x603 },		/* PM_L3_HIT */
195 	{ 0x504, 0x604 },		/* PM_L2_ICACHE_MISS */
196 	{ 0x505, 0x605 },		/* PM_L3_ICACHE_MISS */
197 	{ 0x506, 0x606 },		/* PM_L2_DCACHE_MISS */
198 	{ 0x507, 0x607 },		/* PM_L3_DCACHE_MISS */
199 	{ 0x50a, 0x623 },		/* PM_LD_HIT_L3 */
200 	{ 0x50b, 0x624 },		/* PM_ST_HIT_L3 */
201 	{ 0x50d, 0x60d },		/* PM_L2_TOUCH_HIT */
202 	{ 0x50e, 0x60e },		/* PM_L3_TOUCH_HIT */
203 	{ 0x512, 0x612 },		/* PM_INT_LOCAL */
204 	{ 0x513, 0x61d },		/* PM_L2_MISS */
205 	{ 0x514, 0x61e },		/* PM_L3_MISS */
206 };
207 
208 /*
209  * Scan the alternatives table for a match and return the
210  * index into the alternatives table if found, else -1.
211  */
212 static int find_alternative(u32 event)
213 {
214 	int i, j;
215 
216 	for (i = 0; i < ARRAY_SIZE(event_alternatives); ++i) {
217 		if (event < event_alternatives[i][0])
218 			break;
219 		for (j = 0; j < MAX_ALT && event_alternatives[i][j]; ++j)
220 			if (event == event_alternatives[i][j])
221 				return i;
222 	}
223 	return -1;
224 }
225 
226 static int mpc7450_get_alternatives(u64 event, unsigned int flags, u64 alt[])
227 {
228 	int i, j, nalt = 1;
229 	u32 ae;
230 
231 	alt[0] = event;
232 	nalt = 1;
233 	i = find_alternative((u32)event);
234 	if (i >= 0) {
235 		for (j = 0; j < MAX_ALT; ++j) {
236 			ae = event_alternatives[i][j];
237 			if (ae && ae != (u32)event)
238 				alt[nalt++] = ae;
239 		}
240 	}
241 	return nalt;
242 }
243 
244 /*
245  * Bitmaps of which PMCs each class can use for classes 0 - 3.
246  * Bit i is set if PMC i+1 is usable.
247  */
248 static const u8 classmap[N_CLASSES] = {
249 	0x3f, 0x0f, 0x0b, 0x03, 0
250 };
251 
252 /* Bit position and width of each PMCSEL field */
253 static const int pmcsel_shift[N_COUNTER] = {
254 	6,	0,	27,	22,	17,	11
255 };
256 static const u32 pmcsel_mask[N_COUNTER] = {
257 	0x7f,	0x3f,	0x1f,	0x1f,	0x1f,	0x3f
258 };
259 
260 /*
261  * Compute MMCR0/1/2 values for a set of events.
262  */
263 static int mpc7450_compute_mmcr(u64 event[], int n_ev, unsigned int hwc[],
264 				unsigned long mmcr[],
265 				struct perf_event *pevents[])
266 {
267 	u8 event_index[N_CLASSES][N_COUNTER];
268 	int n_classevent[N_CLASSES];
269 	int i, j, class, tuse;
270 	u32 pmc_inuse = 0, pmc_avail;
271 	u32 mmcr0 = 0, mmcr1 = 0, mmcr2 = 0;
272 	u32 ev, pmc, thresh;
273 
274 	if (n_ev > N_COUNTER)
275 		return -1;
276 
277 	/* First pass: count usage in each class */
278 	for (i = 0; i < N_CLASSES; ++i)
279 		n_classevent[i] = 0;
280 	for (i = 0; i < n_ev; ++i) {
281 		class = mpc7450_classify_event(event[i]);
282 		if (class < 0)
283 			return -1;
284 		j = n_classevent[class]++;
285 		event_index[class][j] = i;
286 	}
287 
288 	/* Second pass: allocate PMCs from most specific event to least */
289 	for (class = N_CLASSES - 1; class >= 0; --class) {
290 		for (i = 0; i < n_classevent[class]; ++i) {
291 			ev = event[event_index[class][i]];
292 			if (class == 4) {
293 				pmc = (ev >> PM_PMC_SH) & PM_PMC_MSK;
294 				if (pmc_inuse & (1 << (pmc - 1)))
295 					return -1;
296 			} else {
297 				/* Find a suitable PMC */
298 				pmc_avail = classmap[class] & ~pmc_inuse;
299 				if (!pmc_avail)
300 					return -1;
301 				pmc = ffs(pmc_avail);
302 			}
303 			pmc_inuse |= 1 << (pmc - 1);
304 
305 			tuse = mpc7450_threshold_use(ev);
306 			if (tuse) {
307 				thresh = (ev >> PM_THRESH_SH) & PM_THRESH_MSK;
308 				mmcr0 |= thresh << 16;
309 				if (tuse == 2 && (ev & PM_THRMULT_MSKS))
310 					mmcr2 = 0x80000000;
311 			}
312 			ev &= pmcsel_mask[pmc - 1];
313 			ev <<= pmcsel_shift[pmc - 1];
314 			if (pmc <= 2)
315 				mmcr0 |= ev;
316 			else
317 				mmcr1 |= ev;
318 			hwc[event_index[class][i]] = pmc - 1;
319 		}
320 	}
321 
322 	if (pmc_inuse & 1)
323 		mmcr0 |= MMCR0_PMC1CE;
324 	if (pmc_inuse & 0x3e)
325 		mmcr0 |= MMCR0_PMCnCE;
326 
327 	/* Return MMCRx values */
328 	mmcr[0] = mmcr0;
329 	mmcr[1] = mmcr1;
330 	mmcr[2] = mmcr2;
331 	return 0;
332 }
333 
334 /*
335  * Disable counting by a PMC.
336  * Note that the pmc argument is 0-based here, not 1-based.
337  */
338 static void mpc7450_disable_pmc(unsigned int pmc, unsigned long mmcr[])
339 {
340 	if (pmc <= 1)
341 		mmcr[0] &= ~(pmcsel_mask[pmc] << pmcsel_shift[pmc]);
342 	else
343 		mmcr[1] &= ~(pmcsel_mask[pmc] << pmcsel_shift[pmc]);
344 }
345 
346 static int mpc7450_generic_events[] = {
347 	[PERF_COUNT_HW_CPU_CYCLES]		= 1,
348 	[PERF_COUNT_HW_INSTRUCTIONS]		= 2,
349 	[PERF_COUNT_HW_CACHE_MISSES]		= 0x217, /* PM_L1_DCACHE_MISS */
350 	[PERF_COUNT_HW_BRANCH_INSTRUCTIONS]	= 0x122, /* PM_BR_CMPL */
351 	[PERF_COUNT_HW_BRANCH_MISSES] 		= 0x41c, /* PM_BR_MPRED */
352 };
353 
354 #define C(x)	PERF_COUNT_HW_CACHE_##x
355 
356 /*
357  * Table of generalized cache-related events.
358  * 0 means not supported, -1 means nonsensical, other values
359  * are event codes.
360  */
361 static int mpc7450_cache_events[C(MAX)][C(OP_MAX)][C(RESULT_MAX)] = {
362 	[C(L1D)] = {		/* 	RESULT_ACCESS	RESULT_MISS */
363 		[C(OP_READ)] = {	0,		0x225	},
364 		[C(OP_WRITE)] = {	0,		0x227	},
365 		[C(OP_PREFETCH)] = {	0,		0	},
366 	},
367 	[C(L1I)] = {		/* 	RESULT_ACCESS	RESULT_MISS */
368 		[C(OP_READ)] = {	0x129,		0x115	},
369 		[C(OP_WRITE)] = {	-1,		-1	},
370 		[C(OP_PREFETCH)] = {	0x634,		0	},
371 	},
372 	[C(LL)] = {		/* 	RESULT_ACCESS	RESULT_MISS */
373 		[C(OP_READ)] = {	0,		0	},
374 		[C(OP_WRITE)] = {	0,		0	},
375 		[C(OP_PREFETCH)] = {	0,		0	},
376 	},
377 	[C(DTLB)] = {		/* 	RESULT_ACCESS	RESULT_MISS */
378 		[C(OP_READ)] = {	0,		0x312	},
379 		[C(OP_WRITE)] = {	-1,		-1	},
380 		[C(OP_PREFETCH)] = {	-1,		-1	},
381 	},
382 	[C(ITLB)] = {		/* 	RESULT_ACCESS	RESULT_MISS */
383 		[C(OP_READ)] = {	0,		0x223	},
384 		[C(OP_WRITE)] = {	-1,		-1	},
385 		[C(OP_PREFETCH)] = {	-1,		-1	},
386 	},
387 	[C(BPU)] = {		/* 	RESULT_ACCESS	RESULT_MISS */
388 		[C(OP_READ)] = {	0x122,		0x41c	},
389 		[C(OP_WRITE)] = {	-1,		-1	},
390 		[C(OP_PREFETCH)] = {	-1,		-1	},
391 	},
392 	[C(NODE)] = {		/* 	RESULT_ACCESS	RESULT_MISS */
393 		[C(OP_READ)] = {	-1,		-1	},
394 		[C(OP_WRITE)] = {	-1,		-1	},
395 		[C(OP_PREFETCH)] = {	-1,		-1	},
396 	},
397 };
398 
399 struct power_pmu mpc7450_pmu = {
400 	.name			= "MPC7450 family",
401 	.n_counter		= N_COUNTER,
402 	.max_alternatives	= MAX_ALT,
403 	.add_fields		= 0x00111555ul,
404 	.test_adder		= 0x00301000ul,
405 	.compute_mmcr		= mpc7450_compute_mmcr,
406 	.get_constraint		= mpc7450_get_constraint,
407 	.get_alternatives	= mpc7450_get_alternatives,
408 	.disable_pmc		= mpc7450_disable_pmc,
409 	.n_generic		= ARRAY_SIZE(mpc7450_generic_events),
410 	.generic_events		= mpc7450_generic_events,
411 	.cache_events		= &mpc7450_cache_events,
412 };
413 
414 static int __init init_mpc7450_pmu(void)
415 {
416 	if (!cur_cpu_spec->oprofile_cpu_type ||
417 	    strcmp(cur_cpu_spec->oprofile_cpu_type, "ppc/7450"))
418 		return -ENODEV;
419 
420 	return register_power_pmu(&mpc7450_pmu);
421 }
422 
423 early_initcall(init_mpc7450_pmu);
424