xref: /linux/arch/powerpc/perf/mpc7450-pmu.c (revision 3c4fc7bf4c9e66fe71abcbf93f62f4ddb89b7f15)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Performance counter support for MPC7450-family processors.
4  *
5  * Copyright 2008-2009 Paul Mackerras, IBM Corporation.
6  */
7 #include <linux/string.h>
8 #include <linux/perf_event.h>
9 #include <asm/reg.h>
10 #include <asm/cputable.h>
11 
12 #define N_COUNTER	6	/* Number of hardware counters */
13 #define MAX_ALT		3	/* Maximum number of event alternative codes */
14 
15 /*
16  * Bits in event code for MPC7450 family
17  */
18 #define PM_THRMULT_MSKS	0x40000
19 #define PM_THRESH_SH	12
20 #define PM_THRESH_MSK	0x3f
21 #define PM_PMC_SH	8
22 #define PM_PMC_MSK	7
23 #define PM_PMCSEL_MSK	0x7f
24 
25 /*
26  * Classify events according to how specific their PMC requirements are.
27  * Result is:
28  *	0: can go on any PMC
29  *	1: can go on PMCs 1-4
30  *	2: can go on PMCs 1,2,4
31  *	3: can go on PMCs 1 or 2
32  *	4: can only go on one PMC
33  *	-1: event code is invalid
34  */
35 #define N_CLASSES	5
36 
37 static int mpc7450_classify_event(u32 event)
38 {
39 	int pmc;
40 
41 	pmc = (event >> PM_PMC_SH) & PM_PMC_MSK;
42 	if (pmc) {
43 		if (pmc > N_COUNTER)
44 			return -1;
45 		return 4;
46 	}
47 	event &= PM_PMCSEL_MSK;
48 	if (event <= 1)
49 		return 0;
50 	if (event <= 7)
51 		return 1;
52 	if (event <= 13)
53 		return 2;
54 	if (event <= 22)
55 		return 3;
56 	return -1;
57 }
58 
59 /*
60  * Events using threshold and possible threshold scale:
61  *	code	scale?	name
62  *	11e	N	PM_INSTQ_EXCEED_CYC
63  *	11f	N	PM_ALTV_IQ_EXCEED_CYC
64  *	128	Y	PM_DTLB_SEARCH_EXCEED_CYC
65  *	12b	Y	PM_LD_MISS_EXCEED_L1_CYC
66  *	220	N	PM_CQ_EXCEED_CYC
67  *	30c	N	PM_GPR_RB_EXCEED_CYC
68  *	30d	?	PM_FPR_IQ_EXCEED_CYC ?
69  *	311	Y	PM_ITLB_SEARCH_EXCEED
70  *	410	N	PM_GPR_IQ_EXCEED_CYC
71  */
72 
73 /*
74  * Return use of threshold and threshold scale bits:
75  * 0 = uses neither, 1 = uses threshold, 2 = uses both
76  */
77 static int mpc7450_threshold_use(u32 event)
78 {
79 	int pmc, sel;
80 
81 	pmc = (event >> PM_PMC_SH) & PM_PMC_MSK;
82 	sel = event & PM_PMCSEL_MSK;
83 	switch (pmc) {
84 	case 1:
85 		if (sel == 0x1e || sel == 0x1f)
86 			return 1;
87 		if (sel == 0x28 || sel == 0x2b)
88 			return 2;
89 		break;
90 	case 2:
91 		if (sel == 0x20)
92 			return 1;
93 		break;
94 	case 3:
95 		if (sel == 0xc || sel == 0xd)
96 			return 1;
97 		if (sel == 0x11)
98 			return 2;
99 		break;
100 	case 4:
101 		if (sel == 0x10)
102 			return 1;
103 		break;
104 	}
105 	return 0;
106 }
107 
108 /*
109  * Layout of constraint bits:
110  * 33222222222211111111110000000000
111  * 10987654321098765432109876543210
112  *  |<    ><  > < > < ><><><><><><>
113  *  TS TV   G4   G3  G2P6P5P4P3P2P1
114  *
115  * P1 - P6
116  *	0 - 11: Count of events needing PMC1 .. PMC6
117  *
118  * G2
119  *	12 - 14: Count of events needing PMC1 or PMC2
120  *
121  * G3
122  *	16 - 18: Count of events needing PMC1, PMC2 or PMC4
123  *
124  * G4
125  *	20 - 23: Count of events needing PMC1, PMC2, PMC3 or PMC4
126  *
127  * TV
128  *	24 - 29: Threshold value requested
129  *
130  * TS
131  *	30: Threshold scale value requested
132  */
133 
134 static u32 pmcbits[N_COUNTER][2] = {
135 	{ 0x00844002, 0x00111001 },	/* PMC1 mask, value: P1,G2,G3,G4 */
136 	{ 0x00844008, 0x00111004 },	/* PMC2: P2,G2,G3,G4 */
137 	{ 0x00800020, 0x00100010 },	/* PMC3: P3,G4 */
138 	{ 0x00840080, 0x00110040 },	/* PMC4: P4,G3,G4 */
139 	{ 0x00000200, 0x00000100 },	/* PMC5: P5 */
140 	{ 0x00000800, 0x00000400 }	/* PMC6: P6 */
141 };
142 
143 static u32 classbits[N_CLASSES - 1][2] = {
144 	{ 0x00000000, 0x00000000 },	/* class 0: no constraint */
145 	{ 0x00800000, 0x00100000 },	/* class 1: G4 */
146 	{ 0x00040000, 0x00010000 },	/* class 2: G3 */
147 	{ 0x00004000, 0x00001000 },	/* class 3: G2 */
148 };
149 
150 static int mpc7450_get_constraint(u64 event, unsigned long *maskp,
151 				  unsigned long *valp, u64 event_config1 __maybe_unused)
152 {
153 	int pmc, class;
154 	u32 mask, value;
155 	int thresh, tuse;
156 
157 	class = mpc7450_classify_event(event);
158 	if (class < 0)
159 		return -1;
160 	if (class == 4) {
161 		pmc = ((unsigned int)event >> PM_PMC_SH) & PM_PMC_MSK;
162 		mask  = pmcbits[pmc - 1][0];
163 		value = pmcbits[pmc - 1][1];
164 	} else {
165 		mask  = classbits[class][0];
166 		value = classbits[class][1];
167 	}
168 
169 	tuse = mpc7450_threshold_use(event);
170 	if (tuse) {
171 		thresh = ((unsigned int)event >> PM_THRESH_SH) & PM_THRESH_MSK;
172 		mask  |= 0x3f << 24;
173 		value |= thresh << 24;
174 		if (tuse == 2) {
175 			mask |= 0x40000000;
176 			if ((unsigned int)event & PM_THRMULT_MSKS)
177 				value |= 0x40000000;
178 		}
179 	}
180 
181 	*maskp = mask;
182 	*valp = value;
183 	return 0;
184 }
185 
186 static const unsigned int event_alternatives[][MAX_ALT] = {
187 	{ 0x217, 0x317 },		/* PM_L1_DCACHE_MISS */
188 	{ 0x418, 0x50f, 0x60f },	/* PM_SNOOP_RETRY */
189 	{ 0x502, 0x602 },		/* PM_L2_HIT */
190 	{ 0x503, 0x603 },		/* PM_L3_HIT */
191 	{ 0x504, 0x604 },		/* PM_L2_ICACHE_MISS */
192 	{ 0x505, 0x605 },		/* PM_L3_ICACHE_MISS */
193 	{ 0x506, 0x606 },		/* PM_L2_DCACHE_MISS */
194 	{ 0x507, 0x607 },		/* PM_L3_DCACHE_MISS */
195 	{ 0x50a, 0x623 },		/* PM_LD_HIT_L3 */
196 	{ 0x50b, 0x624 },		/* PM_ST_HIT_L3 */
197 	{ 0x50d, 0x60d },		/* PM_L2_TOUCH_HIT */
198 	{ 0x50e, 0x60e },		/* PM_L3_TOUCH_HIT */
199 	{ 0x512, 0x612 },		/* PM_INT_LOCAL */
200 	{ 0x513, 0x61d },		/* PM_L2_MISS */
201 	{ 0x514, 0x61e },		/* PM_L3_MISS */
202 };
203 
204 /*
205  * Scan the alternatives table for a match and return the
206  * index into the alternatives table if found, else -1.
207  */
208 static int find_alternative(u32 event)
209 {
210 	int i, j;
211 
212 	for (i = 0; i < ARRAY_SIZE(event_alternatives); ++i) {
213 		if (event < event_alternatives[i][0])
214 			break;
215 		for (j = 0; j < MAX_ALT && event_alternatives[i][j]; ++j)
216 			if (event == event_alternatives[i][j])
217 				return i;
218 	}
219 	return -1;
220 }
221 
222 static int mpc7450_get_alternatives(u64 event, unsigned int flags, u64 alt[])
223 {
224 	int i, j, nalt = 1;
225 	u32 ae;
226 
227 	alt[0] = event;
228 	nalt = 1;
229 	i = find_alternative((u32)event);
230 	if (i >= 0) {
231 		for (j = 0; j < MAX_ALT; ++j) {
232 			ae = event_alternatives[i][j];
233 			if (ae && ae != (u32)event)
234 				alt[nalt++] = ae;
235 		}
236 	}
237 	return nalt;
238 }
239 
240 /*
241  * Bitmaps of which PMCs each class can use for classes 0 - 3.
242  * Bit i is set if PMC i+1 is usable.
243  */
244 static const u8 classmap[N_CLASSES] = {
245 	0x3f, 0x0f, 0x0b, 0x03, 0
246 };
247 
248 /* Bit position and width of each PMCSEL field */
249 static const int pmcsel_shift[N_COUNTER] = {
250 	6,	0,	27,	22,	17,	11
251 };
252 static const u32 pmcsel_mask[N_COUNTER] = {
253 	0x7f,	0x3f,	0x1f,	0x1f,	0x1f,	0x3f
254 };
255 
256 /*
257  * Compute MMCR0/1/2 values for a set of events.
258  */
259 static int mpc7450_compute_mmcr(u64 event[], int n_ev, unsigned int hwc[],
260 				struct mmcr_regs *mmcr,
261 				struct perf_event *pevents[],
262 				u32 flags __maybe_unused)
263 {
264 	u8 event_index[N_CLASSES][N_COUNTER];
265 	int n_classevent[N_CLASSES];
266 	int i, j, class, tuse;
267 	u32 pmc_inuse = 0, pmc_avail;
268 	u32 mmcr0 = 0, mmcr1 = 0, mmcr2 = 0;
269 	u32 ev, pmc, thresh;
270 
271 	if (n_ev > N_COUNTER)
272 		return -1;
273 
274 	/* First pass: count usage in each class */
275 	for (i = 0; i < N_CLASSES; ++i)
276 		n_classevent[i] = 0;
277 	for (i = 0; i < n_ev; ++i) {
278 		class = mpc7450_classify_event(event[i]);
279 		if (class < 0)
280 			return -1;
281 		j = n_classevent[class]++;
282 		event_index[class][j] = i;
283 	}
284 
285 	/* Second pass: allocate PMCs from most specific event to least */
286 	for (class = N_CLASSES - 1; class >= 0; --class) {
287 		for (i = 0; i < n_classevent[class]; ++i) {
288 			ev = event[event_index[class][i]];
289 			if (class == 4) {
290 				pmc = (ev >> PM_PMC_SH) & PM_PMC_MSK;
291 				if (pmc_inuse & (1 << (pmc - 1)))
292 					return -1;
293 			} else {
294 				/* Find a suitable PMC */
295 				pmc_avail = classmap[class] & ~pmc_inuse;
296 				if (!pmc_avail)
297 					return -1;
298 				pmc = ffs(pmc_avail);
299 			}
300 			pmc_inuse |= 1 << (pmc - 1);
301 
302 			tuse = mpc7450_threshold_use(ev);
303 			if (tuse) {
304 				thresh = (ev >> PM_THRESH_SH) & PM_THRESH_MSK;
305 				mmcr0 |= thresh << 16;
306 				if (tuse == 2 && (ev & PM_THRMULT_MSKS))
307 					mmcr2 = 0x80000000;
308 			}
309 			ev &= pmcsel_mask[pmc - 1];
310 			ev <<= pmcsel_shift[pmc - 1];
311 			if (pmc <= 2)
312 				mmcr0 |= ev;
313 			else
314 				mmcr1 |= ev;
315 			hwc[event_index[class][i]] = pmc - 1;
316 		}
317 	}
318 
319 	if (pmc_inuse & 1)
320 		mmcr0 |= MMCR0_PMC1CE;
321 	if (pmc_inuse & 0x3e)
322 		mmcr0 |= MMCR0_PMCnCE;
323 
324 	/* Return MMCRx values */
325 	mmcr->mmcr0 = mmcr0;
326 	mmcr->mmcr1 = mmcr1;
327 	mmcr->mmcr2 = mmcr2;
328 	/*
329 	 * 32-bit doesn't have an MMCRA and uses SPRN_MMCR2 to define
330 	 * SPRN_MMCRA. So assign mmcra of cpu_hw_events with `mmcr2`
331 	 * value to ensure that any write to this SPRN_MMCRA will
332 	 * use mmcr2 value.
333 	 */
334 	mmcr->mmcra = mmcr2;
335 	return 0;
336 }
337 
338 /*
339  * Disable counting by a PMC.
340  * Note that the pmc argument is 0-based here, not 1-based.
341  */
342 static void mpc7450_disable_pmc(unsigned int pmc, struct mmcr_regs *mmcr)
343 {
344 	if (pmc <= 1)
345 		mmcr->mmcr0 &= ~(pmcsel_mask[pmc] << pmcsel_shift[pmc]);
346 	else
347 		mmcr->mmcr1 &= ~(pmcsel_mask[pmc] << pmcsel_shift[pmc]);
348 }
349 
350 static int mpc7450_generic_events[] = {
351 	[PERF_COUNT_HW_CPU_CYCLES]		= 1,
352 	[PERF_COUNT_HW_INSTRUCTIONS]		= 2,
353 	[PERF_COUNT_HW_CACHE_MISSES]		= 0x217, /* PM_L1_DCACHE_MISS */
354 	[PERF_COUNT_HW_BRANCH_INSTRUCTIONS]	= 0x122, /* PM_BR_CMPL */
355 	[PERF_COUNT_HW_BRANCH_MISSES] 		= 0x41c, /* PM_BR_MPRED */
356 };
357 
358 #define C(x)	PERF_COUNT_HW_CACHE_##x
359 
360 /*
361  * Table of generalized cache-related events.
362  * 0 means not supported, -1 means nonsensical, other values
363  * are event codes.
364  */
365 static u64 mpc7450_cache_events[C(MAX)][C(OP_MAX)][C(RESULT_MAX)] = {
366 	[C(L1D)] = {		/* 	RESULT_ACCESS	RESULT_MISS */
367 		[C(OP_READ)] = {	0,		0x225	},
368 		[C(OP_WRITE)] = {	0,		0x227	},
369 		[C(OP_PREFETCH)] = {	0,		0	},
370 	},
371 	[C(L1I)] = {		/* 	RESULT_ACCESS	RESULT_MISS */
372 		[C(OP_READ)] = {	0x129,		0x115	},
373 		[C(OP_WRITE)] = {	-1,		-1	},
374 		[C(OP_PREFETCH)] = {	0x634,		0	},
375 	},
376 	[C(LL)] = {		/* 	RESULT_ACCESS	RESULT_MISS */
377 		[C(OP_READ)] = {	0,		0	},
378 		[C(OP_WRITE)] = {	0,		0	},
379 		[C(OP_PREFETCH)] = {	0,		0	},
380 	},
381 	[C(DTLB)] = {		/* 	RESULT_ACCESS	RESULT_MISS */
382 		[C(OP_READ)] = {	0,		0x312	},
383 		[C(OP_WRITE)] = {	-1,		-1	},
384 		[C(OP_PREFETCH)] = {	-1,		-1	},
385 	},
386 	[C(ITLB)] = {		/* 	RESULT_ACCESS	RESULT_MISS */
387 		[C(OP_READ)] = {	0,		0x223	},
388 		[C(OP_WRITE)] = {	-1,		-1	},
389 		[C(OP_PREFETCH)] = {	-1,		-1	},
390 	},
391 	[C(BPU)] = {		/* 	RESULT_ACCESS	RESULT_MISS */
392 		[C(OP_READ)] = {	0x122,		0x41c	},
393 		[C(OP_WRITE)] = {	-1,		-1	},
394 		[C(OP_PREFETCH)] = {	-1,		-1	},
395 	},
396 	[C(NODE)] = {		/* 	RESULT_ACCESS	RESULT_MISS */
397 		[C(OP_READ)] = {	-1,		-1	},
398 		[C(OP_WRITE)] = {	-1,		-1	},
399 		[C(OP_PREFETCH)] = {	-1,		-1	},
400 	},
401 };
402 
403 struct power_pmu mpc7450_pmu = {
404 	.name			= "MPC7450 family",
405 	.n_counter		= N_COUNTER,
406 	.max_alternatives	= MAX_ALT,
407 	.add_fields		= 0x00111555ul,
408 	.test_adder		= 0x00301000ul,
409 	.compute_mmcr		= mpc7450_compute_mmcr,
410 	.get_constraint		= mpc7450_get_constraint,
411 	.get_alternatives	= mpc7450_get_alternatives,
412 	.disable_pmc		= mpc7450_disable_pmc,
413 	.n_generic		= ARRAY_SIZE(mpc7450_generic_events),
414 	.generic_events		= mpc7450_generic_events,
415 	.cache_events		= &mpc7450_cache_events,
416 };
417 
418 static int __init init_mpc7450_pmu(void)
419 {
420 	unsigned int pvr = mfspr(SPRN_PVR);
421 
422 	if (PVR_VER(pvr) != PVR_7450)
423 		return -ENODEV;
424 
425 	return register_power_pmu(&mpc7450_pmu);
426 }
427 
428 early_initcall(init_mpc7450_pmu);
429