1 /*
2  * Performance counter support for POWER7 processors.
3  *
4  * Copyright 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/kernel.h>
12 #include <linux/perf_event.h>
13 #include <linux/string.h>
14 #include <asm/reg.h>
15 #include <asm/cputable.h>
16 
17 /*
18  * Bits in event code for POWER7
19  */
20 #define PM_PMC_SH	16	/* PMC number (1-based) for direct events */
21 #define PM_PMC_MSK	0xf
22 #define PM_PMC_MSKS	(PM_PMC_MSK << PM_PMC_SH)
23 #define PM_UNIT_SH	12	/* TTMMUX number and setting - unit select */
24 #define PM_UNIT_MSK	0xf
25 #define PM_COMBINE_SH	11	/* Combined event bit */
26 #define PM_COMBINE_MSK	1
27 #define PM_COMBINE_MSKS	0x800
28 #define PM_L2SEL_SH	8	/* L2 event select */
29 #define PM_L2SEL_MSK	7
30 #define PM_PMCSEL_MSK	0xff
31 
32 /*
33  * Bits in MMCR1 for POWER7
34  */
35 #define MMCR1_TTM0SEL_SH	60
36 #define MMCR1_TTM1SEL_SH	56
37 #define MMCR1_TTM2SEL_SH	52
38 #define MMCR1_TTM3SEL_SH	48
39 #define MMCR1_TTMSEL_MSK	0xf
40 #define MMCR1_L2SEL_SH		45
41 #define MMCR1_L2SEL_MSK		7
42 #define MMCR1_PMC1_COMBINE_SH	35
43 #define MMCR1_PMC2_COMBINE_SH	34
44 #define MMCR1_PMC3_COMBINE_SH	33
45 #define MMCR1_PMC4_COMBINE_SH	32
46 #define MMCR1_PMC1SEL_SH	24
47 #define MMCR1_PMC2SEL_SH	16
48 #define MMCR1_PMC3SEL_SH	8
49 #define MMCR1_PMC4SEL_SH	0
50 #define MMCR1_PMCSEL_SH(n)	(MMCR1_PMC1SEL_SH - (n) * 8)
51 #define MMCR1_PMCSEL_MSK	0xff
52 
53 /*
54  * Layout of constraint bits:
55  * 6666555555555544444444443333333333222222222211111111110000000000
56  * 3210987654321098765432109876543210987654321098765432109876543210
57  *                                                 [  ><><><><><><>
58  *                                                  NC P6P5P4P3P2P1
59  *
60  * NC - number of counters
61  *     15: NC error 0x8000
62  *     12-14: number of events needing PMC1-4 0x7000
63  *
64  * P6
65  *     11: P6 error 0x800
66  *     10-11: Count of events needing PMC6
67  *
68  * P1..P5
69  *     0-9: Count of events needing PMC1..PMC5
70  */
71 
power7_get_constraint(u64 event,unsigned long * maskp,unsigned long * valp)72 static int power7_get_constraint(u64 event, unsigned long *maskp,
73 				 unsigned long *valp)
74 {
75 	int pmc, sh;
76 	unsigned long mask = 0, value = 0;
77 
78 	pmc = (event >> PM_PMC_SH) & PM_PMC_MSK;
79 	if (pmc) {
80 		if (pmc > 6)
81 			return -1;
82 		sh = (pmc - 1) * 2;
83 		mask |= 2 << sh;
84 		value |= 1 << sh;
85 		if (pmc >= 5 && !(event == 0x500fa || event == 0x600f4))
86 			return -1;
87 	}
88 	if (pmc < 5) {
89 		/* need a counter from PMC1-4 set */
90 		mask  |= 0x8000;
91 		value |= 0x1000;
92 	}
93 	*maskp = mask;
94 	*valp = value;
95 	return 0;
96 }
97 
98 #define MAX_ALT	2	/* at most 2 alternatives for any event */
99 
100 static const unsigned int event_alternatives[][MAX_ALT] = {
101 	{ 0x200f2, 0x300f2 },		/* PM_INST_DISP */
102 	{ 0x200f4, 0x600f4 },		/* PM_RUN_CYC */
103 	{ 0x400fa, 0x500fa },		/* PM_RUN_INST_CMPL */
104 };
105 
106 /*
107  * Scan the alternatives table for a match and return the
108  * index into the alternatives table if found, else -1.
109  */
find_alternative(u64 event)110 static int find_alternative(u64 event)
111 {
112 	int i, j;
113 
114 	for (i = 0; i < ARRAY_SIZE(event_alternatives); ++i) {
115 		if (event < event_alternatives[i][0])
116 			break;
117 		for (j = 0; j < MAX_ALT && event_alternatives[i][j]; ++j)
118 			if (event == event_alternatives[i][j])
119 				return i;
120 	}
121 	return -1;
122 }
123 
find_alternative_decode(u64 event)124 static s64 find_alternative_decode(u64 event)
125 {
126 	int pmc, psel;
127 
128 	/* this only handles the 4x decode events */
129 	pmc = (event >> PM_PMC_SH) & PM_PMC_MSK;
130 	psel = event & PM_PMCSEL_MSK;
131 	if ((pmc == 2 || pmc == 4) && (psel & ~7) == 0x40)
132 		return event - (1 << PM_PMC_SH) + 8;
133 	if ((pmc == 1 || pmc == 3) && (psel & ~7) == 0x48)
134 		return event + (1 << PM_PMC_SH) - 8;
135 	return -1;
136 }
137 
power7_get_alternatives(u64 event,unsigned int flags,u64 alt[])138 static int power7_get_alternatives(u64 event, unsigned int flags, u64 alt[])
139 {
140 	int i, j, nalt = 1;
141 	s64 ae;
142 
143 	alt[0] = event;
144 	nalt = 1;
145 	i = find_alternative(event);
146 	if (i >= 0) {
147 		for (j = 0; j < MAX_ALT; ++j) {
148 			ae = event_alternatives[i][j];
149 			if (ae && ae != event)
150 				alt[nalt++] = ae;
151 		}
152 	} else {
153 		ae = find_alternative_decode(event);
154 		if (ae > 0)
155 			alt[nalt++] = ae;
156 	}
157 
158 	if (flags & PPMU_ONLY_COUNT_RUN) {
159 		/*
160 		 * We're only counting in RUN state,
161 		 * so PM_CYC is equivalent to PM_RUN_CYC
162 		 * and PM_INST_CMPL === PM_RUN_INST_CMPL.
163 		 * This doesn't include alternatives that don't provide
164 		 * any extra flexibility in assigning PMCs.
165 		 */
166 		j = nalt;
167 		for (i = 0; i < nalt; ++i) {
168 			switch (alt[i]) {
169 			case 0x1e:	/* PM_CYC */
170 				alt[j++] = 0x600f4;	/* PM_RUN_CYC */
171 				break;
172 			case 0x600f4:	/* PM_RUN_CYC */
173 				alt[j++] = 0x1e;
174 				break;
175 			case 0x2:	/* PM_PPC_CMPL */
176 				alt[j++] = 0x500fa;	/* PM_RUN_INST_CMPL */
177 				break;
178 			case 0x500fa:	/* PM_RUN_INST_CMPL */
179 				alt[j++] = 0x2;	/* PM_PPC_CMPL */
180 				break;
181 			}
182 		}
183 		nalt = j;
184 	}
185 
186 	return nalt;
187 }
188 
189 /*
190  * Returns 1 if event counts things relating to marked instructions
191  * and thus needs the MMCRA_SAMPLE_ENABLE bit set, or 0 if not.
192  */
power7_marked_instr_event(u64 event)193 static int power7_marked_instr_event(u64 event)
194 {
195 	int pmc, psel;
196 	int unit;
197 
198 	pmc = (event >> PM_PMC_SH) & PM_PMC_MSK;
199 	unit = (event >> PM_UNIT_SH) & PM_UNIT_MSK;
200 	psel = event & PM_PMCSEL_MSK & ~1;	/* trim off edge/level bit */
201 	if (pmc >= 5)
202 		return 0;
203 
204 	switch (psel >> 4) {
205 	case 2:
206 		return pmc == 2 || pmc == 4;
207 	case 3:
208 		if (psel == 0x3c)
209 			return pmc == 1;
210 		if (psel == 0x3e)
211 			return pmc != 2;
212 		return 1;
213 	case 4:
214 	case 5:
215 		return unit == 0xd;
216 	case 6:
217 		if (psel == 0x64)
218 			return pmc >= 3;
219 	case 8:
220 		return unit == 0xd;
221 	}
222 	return 0;
223 }
224 
power7_compute_mmcr(u64 event[],int n_ev,unsigned int hwc[],unsigned long mmcr[])225 static int power7_compute_mmcr(u64 event[], int n_ev,
226 			       unsigned int hwc[], unsigned long mmcr[])
227 {
228 	unsigned long mmcr1 = 0;
229 	unsigned long mmcra = MMCRA_SDAR_DCACHE_MISS | MMCRA_SDAR_ERAT_MISS;
230 	unsigned int pmc, unit, combine, l2sel, psel;
231 	unsigned int pmc_inuse = 0;
232 	int i;
233 
234 	/* First pass to count resource use */
235 	for (i = 0; i < n_ev; ++i) {
236 		pmc = (event[i] >> PM_PMC_SH) & PM_PMC_MSK;
237 		if (pmc) {
238 			if (pmc > 6)
239 				return -1;
240 			if (pmc_inuse & (1 << (pmc - 1)))
241 				return -1;
242 			pmc_inuse |= 1 << (pmc - 1);
243 		}
244 	}
245 
246 	/* Second pass: assign PMCs, set all MMCR1 fields */
247 	for (i = 0; i < n_ev; ++i) {
248 		pmc = (event[i] >> PM_PMC_SH) & PM_PMC_MSK;
249 		unit = (event[i] >> PM_UNIT_SH) & PM_UNIT_MSK;
250 		combine = (event[i] >> PM_COMBINE_SH) & PM_COMBINE_MSK;
251 		l2sel = (event[i] >> PM_L2SEL_SH) & PM_L2SEL_MSK;
252 		psel = event[i] & PM_PMCSEL_MSK;
253 		if (!pmc) {
254 			/* Bus event or any-PMC direct event */
255 			for (pmc = 0; pmc < 4; ++pmc) {
256 				if (!(pmc_inuse & (1 << pmc)))
257 					break;
258 			}
259 			if (pmc >= 4)
260 				return -1;
261 			pmc_inuse |= 1 << pmc;
262 		} else {
263 			/* Direct or decoded event */
264 			--pmc;
265 		}
266 		if (pmc <= 3) {
267 			mmcr1 |= (unsigned long) unit
268 				<< (MMCR1_TTM0SEL_SH - 4 * pmc);
269 			mmcr1 |= (unsigned long) combine
270 				<< (MMCR1_PMC1_COMBINE_SH - pmc);
271 			mmcr1 |= psel << MMCR1_PMCSEL_SH(pmc);
272 			if (unit == 6)	/* L2 events */
273 				mmcr1 |= (unsigned long) l2sel
274 					<< MMCR1_L2SEL_SH;
275 		}
276 		if (power7_marked_instr_event(event[i]))
277 			mmcra |= MMCRA_SAMPLE_ENABLE;
278 		hwc[i] = pmc;
279 	}
280 
281 	/* Return MMCRx values */
282 	mmcr[0] = 0;
283 	if (pmc_inuse & 1)
284 		mmcr[0] = MMCR0_PMC1CE;
285 	if (pmc_inuse & 0x3e)
286 		mmcr[0] |= MMCR0_PMCjCE;
287 	mmcr[1] = mmcr1;
288 	mmcr[2] = mmcra;
289 	return 0;
290 }
291 
power7_disable_pmc(unsigned int pmc,unsigned long mmcr[])292 static void power7_disable_pmc(unsigned int pmc, unsigned long mmcr[])
293 {
294 	if (pmc <= 3)
295 		mmcr[1] &= ~(0xffUL << MMCR1_PMCSEL_SH(pmc));
296 }
297 
298 static int power7_generic_events[] = {
299 	[PERF_COUNT_HW_CPU_CYCLES] = 0x1e,
300 	[PERF_COUNT_HW_INSTRUCTIONS] = 2,
301 	[PERF_COUNT_HW_CACHE_REFERENCES] = 0xc880,	/* LD_REF_L1_LSU*/
302 	[PERF_COUNT_HW_CACHE_MISSES] = 0x400f0,		/* LD_MISS_L1	*/
303 	[PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = 0x10068,	/* BRU_FIN	*/
304 	[PERF_COUNT_HW_BRANCH_MISSES] = 0x400f6,	/* BR_MPRED	*/
305 };
306 
307 #define C(x)	PERF_COUNT_HW_CACHE_##x
308 
309 /*
310  * Table of generalized cache-related events.
311  * 0 means not supported, -1 means nonsensical, other values
312  * are event codes.
313  */
314 static int power7_cache_events[C(MAX)][C(OP_MAX)][C(RESULT_MAX)] = {
315 	[C(L1D)] = {		/* 	RESULT_ACCESS	RESULT_MISS */
316 		[C(OP_READ)] = {	0xc880,		0x400f0	},
317 		[C(OP_WRITE)] = {	0,		0x300f0	},
318 		[C(OP_PREFETCH)] = {	0xd8b8,		0	},
319 	},
320 	[C(L1I)] = {		/* 	RESULT_ACCESS	RESULT_MISS */
321 		[C(OP_READ)] = {	0,		0x200fc	},
322 		[C(OP_WRITE)] = {	-1,		-1	},
323 		[C(OP_PREFETCH)] = {	0x408a,		0	},
324 	},
325 	[C(LL)] = {		/* 	RESULT_ACCESS	RESULT_MISS */
326 		[C(OP_READ)] = {	0x16080,	0x26080	},
327 		[C(OP_WRITE)] = {	0x16082,	0x26082	},
328 		[C(OP_PREFETCH)] = {	0,		0	},
329 	},
330 	[C(DTLB)] = {		/* 	RESULT_ACCESS	RESULT_MISS */
331 		[C(OP_READ)] = {	0,		0x300fc	},
332 		[C(OP_WRITE)] = {	-1,		-1	},
333 		[C(OP_PREFETCH)] = {	-1,		-1	},
334 	},
335 	[C(ITLB)] = {		/* 	RESULT_ACCESS	RESULT_MISS */
336 		[C(OP_READ)] = {	0,		0x400fc	},
337 		[C(OP_WRITE)] = {	-1,		-1	},
338 		[C(OP_PREFETCH)] = {	-1,		-1	},
339 	},
340 	[C(BPU)] = {		/* 	RESULT_ACCESS	RESULT_MISS */
341 		[C(OP_READ)] = {	0x10068,	0x400f6	},
342 		[C(OP_WRITE)] = {	-1,		-1	},
343 		[C(OP_PREFETCH)] = {	-1,		-1	},
344 	},
345 };
346 
347 static struct power_pmu power7_pmu = {
348 	.name			= "POWER7",
349 	.n_counter		= 6,
350 	.max_alternatives	= MAX_ALT + 1,
351 	.add_fields		= 0x1555ul,
352 	.test_adder		= 0x3000ul,
353 	.compute_mmcr		= power7_compute_mmcr,
354 	.get_constraint		= power7_get_constraint,
355 	.get_alternatives	= power7_get_alternatives,
356 	.disable_pmc		= power7_disable_pmc,
357 	.flags			= PPMU_ALT_SIPR,
358 	.n_generic		= ARRAY_SIZE(power7_generic_events),
359 	.generic_events		= power7_generic_events,
360 	.cache_events		= &power7_cache_events,
361 };
362 
init_power7_pmu(void)363 static int init_power7_pmu(void)
364 {
365 	if (!cur_cpu_spec->oprofile_cpu_type ||
366 	    strcmp(cur_cpu_spec->oprofile_cpu_type, "ppc64/power7"))
367 		return -ENODEV;
368 
369 	return register_power_pmu(&power7_pmu);
370 }
371 
372 early_initcall(init_power7_pmu);
373