xref: /freebsd/sys/dev/hwpmc/hwpmc_powerpc.c (revision 53b70c86)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2011,2013 Justin Hibbits
5  * Copyright (c) 2005, Joseph Koshy
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  */
30 
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
33 
34 #include <sys/param.h>
35 #include <sys/pmc.h>
36 #include <sys/pmckern.h>
37 #include <sys/sysent.h>
38 #include <sys/syslog.h>
39 #include <sys/systm.h>
40 
41 #include <machine/pmc_mdep.h>
42 #include <machine/spr.h>
43 #include <machine/pte.h>
44 #include <machine/sr.h>
45 #include <machine/cpu.h>
46 #include <machine/stack.h>
47 
48 #include "hwpmc_powerpc.h"
49 
50 #ifdef __powerpc64__
51 #define OFFSET 4 /* Account for the TOC reload slot */
52 #else
53 #define OFFSET 0
54 #endif
55 
56 struct powerpc_cpu **powerpc_pcpu;
57 struct pmc_ppc_event *ppc_event_codes;
58 size_t ppc_event_codes_size;
59 int ppc_event_first;
60 int ppc_event_last;
61 int ppc_max_pmcs;
62 enum pmc_class ppc_class;
63 
64 void (*powerpc_set_pmc)(int cpu, int ri, int config);
65 pmc_value_t (*powerpc_pmcn_read)(unsigned int pmc);
66 void (*powerpc_pmcn_write)(unsigned int pmc, uint32_t val);
67 void (*powerpc_resume_pmc)(bool ie);
68 
69 
70 int
71 pmc_save_kernel_callchain(uintptr_t *cc, int maxsamples,
72     struct trapframe *tf)
73 {
74 	uintptr_t *osp, *sp;
75 	uintptr_t pc;
76 	int frames = 0;
77 
78 	cc[frames++] = PMC_TRAPFRAME_TO_PC(tf);
79 	sp = (uintptr_t *)PMC_TRAPFRAME_TO_FP(tf);
80 	osp = (uintptr_t *)PAGE_SIZE;
81 
82 	for (; frames < maxsamples; frames++) {
83 		if (sp <= osp)
84 			break;
85 	    #ifdef __powerpc64__
86 		pc = sp[2];
87 	    #else
88 		pc = sp[1];
89 	    #endif
90 		if ((pc & 3) || (pc < 0x100))
91 			break;
92 
93 		/*
94 		 * trapexit() and asttrapexit() are sentinels
95 		 * for kernel stack tracing.
96 		 * */
97 		if (pc + OFFSET == (uintptr_t) &trapexit ||
98 		    pc + OFFSET == (uintptr_t) &asttrapexit)
99 			break;
100 
101 		cc[frames] = pc;
102 		osp = sp;
103 		sp = (uintptr_t *)*sp;
104 	}
105 	return (frames);
106 }
107 
108 static int
109 powerpc_switch_in(struct pmc_cpu *pc, struct pmc_process *pp)
110 {
111 
112 	return (0);
113 }
114 
115 static int
116 powerpc_switch_out(struct pmc_cpu *pc, struct pmc_process *pp)
117 {
118 
119 	return (0);
120 }
121 
122 int
123 powerpc_describe(int cpu, int ri, struct pmc_info *pi, struct pmc **ppmc)
124 {
125 	int error;
126 	struct pmc_hw *phw;
127 	char powerpc_name[PMC_NAME_MAX];
128 
129 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
130 	    ("[powerpc,%d], illegal CPU %d", __LINE__, cpu));
131 
132 	phw = &powerpc_pcpu[cpu]->pc_ppcpmcs[ri];
133 	snprintf(powerpc_name, sizeof(powerpc_name), "POWERPC-%d", ri);
134 	if ((error = copystr(powerpc_name, pi->pm_name, PMC_NAME_MAX,
135 	    NULL)) != 0)
136 		return error;
137 	pi->pm_class = powerpc_pcpu[cpu]->pc_class;
138 	if (phw->phw_state & PMC_PHW_FLAG_IS_ENABLED) {
139 		pi->pm_enabled = TRUE;
140 		*ppmc          = phw->phw_pmc;
141 	} else {
142 		pi->pm_enabled = FALSE;
143 		*ppmc	       = NULL;
144 	}
145 
146 	return (0);
147 }
148 
149 int
150 powerpc_get_config(int cpu, int ri, struct pmc **ppm)
151 {
152 
153 	*ppm = powerpc_pcpu[cpu]->pc_ppcpmcs[ri].phw_pmc;
154 
155 	return (0);
156 }
157 
158 int
159 powerpc_pcpu_init(struct pmc_mdep *md, int cpu)
160 {
161 	struct pmc_cpu *pc;
162 	struct powerpc_cpu *pac;
163 	struct pmc_hw  *phw;
164 	int first_ri, i;
165 
166 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
167 	    ("[powerpc,%d] wrong cpu number %d", __LINE__, cpu));
168 	PMCDBG1(MDP,INI,1,"powerpc-init cpu=%d", cpu);
169 
170 	powerpc_pcpu[cpu] = pac = malloc(sizeof(struct powerpc_cpu), M_PMC,
171 	    M_WAITOK|M_ZERO);
172 	pac->pc_ppcpmcs = malloc(sizeof(struct pmc_hw) * ppc_max_pmcs,
173 	    M_PMC, M_WAITOK|M_ZERO);
174 	pac->pc_class =
175 	    md->pmd_classdep[PMC_MDEP_CLASS_INDEX_POWERPC].pcd_class;
176 
177 	pc = pmc_pcpu[cpu];
178 	first_ri = md->pmd_classdep[PMC_MDEP_CLASS_INDEX_POWERPC].pcd_ri;
179 	KASSERT(pc != NULL, ("[powerpc,%d] NULL per-cpu pointer", __LINE__));
180 
181 	for (i = 0, phw = pac->pc_ppcpmcs; i < ppc_max_pmcs; i++, phw++) {
182 		phw->phw_state = PMC_PHW_FLAG_IS_ENABLED |
183 		    PMC_PHW_CPU_TO_STATE(cpu) | PMC_PHW_INDEX_TO_STATE(i);
184 		phw->phw_pmc = NULL;
185 		pc->pc_hwpmcs[i + first_ri] = phw;
186 	}
187 
188 	return (0);
189 }
190 
191 int
192 powerpc_pcpu_fini(struct pmc_mdep *md, int cpu)
193 {
194 	PMCDBG1(MDP,INI,1,"powerpc-fini cpu=%d", cpu);
195 
196 	free(powerpc_pcpu[cpu]->pc_ppcpmcs, M_PMC);
197 	free(powerpc_pcpu[cpu], M_PMC);
198 
199 	return (0);
200 }
201 
202 int
203 powerpc_allocate_pmc(int cpu, int ri, struct pmc *pm,
204     const struct pmc_op_pmcallocate *a)
205 {
206 	enum pmc_event pe;
207 	uint32_t caps, config = 0, counter = 0;
208 	int i;
209 
210 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
211 	    ("[powerpc,%d] illegal CPU value %d", __LINE__, cpu));
212 	KASSERT(ri >= 0 && ri < ppc_max_pmcs,
213 	    ("[powerpc,%d] illegal row index %d", __LINE__, ri));
214 
215 	if (a->pm_class != ppc_class)
216 		return (EINVAL);
217 
218 	caps = a->pm_caps;
219 
220 	pe = a->pm_ev;
221 
222 	if (pe < ppc_event_first || pe > ppc_event_last)
223 		return (EINVAL);
224 
225 	for (i = 0; i < ppc_event_codes_size; i++) {
226 		if (ppc_event_codes[i].pe_event == pe) {
227 			config = ppc_event_codes[i].pe_code;
228 			counter =  ppc_event_codes[i].pe_flags;
229 			break;
230 		}
231 	}
232 	if (i == ppc_event_codes_size)
233 		return (EINVAL);
234 
235 	if ((counter & (1 << ri)) == 0)
236 		return (EINVAL);
237 
238 	if (caps & PMC_CAP_SYSTEM)
239 		config |= POWERPC_PMC_KERNEL_ENABLE;
240 	if (caps & PMC_CAP_USER)
241 		config |= POWERPC_PMC_USER_ENABLE;
242 	if ((caps & (PMC_CAP_USER | PMC_CAP_SYSTEM)) == 0)
243 		config |= POWERPC_PMC_ENABLE;
244 
245 	pm->pm_md.pm_powerpc.pm_powerpc_evsel = config;
246 
247 	PMCDBG3(MDP,ALL,1,"powerpc-allocate cpu=%d ri=%d -> config=0x%x",
248 	    cpu, ri, config);
249 	return (0);
250 }
251 
252 int
253 powerpc_release_pmc(int cpu, int ri, struct pmc *pmc)
254 {
255 	struct pmc_hw *phw;
256 
257 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
258 	    ("[powerpc,%d] illegal CPU value %d", __LINE__, cpu));
259 	KASSERT(ri >= 0 && ri < ppc_max_pmcs,
260 	    ("[powerpc,%d] illegal row-index %d", __LINE__, ri));
261 
262 	phw = &powerpc_pcpu[cpu]->pc_ppcpmcs[ri];
263 	KASSERT(phw->phw_pmc == NULL,
264 	    ("[powerpc,%d] PHW pmc %p non-NULL", __LINE__, phw->phw_pmc));
265 
266 	return (0);
267 }
268 
269 int
270 powerpc_start_pmc(int cpu, int ri)
271 {
272 	struct pmc *pm;
273 
274 	PMCDBG2(MDP,STA,1,"powerpc-start cpu=%d ri=%d", cpu, ri);
275 	pm = powerpc_pcpu[cpu]->pc_ppcpmcs[ri].phw_pmc;
276 	powerpc_set_pmc(cpu, ri, pm->pm_md.pm_powerpc.pm_powerpc_evsel);
277 
278 	return (0);
279 }
280 
281 int
282 powerpc_stop_pmc(int cpu, int ri)
283 {
284 	PMCDBG2(MDP,STO,1, "powerpc-stop cpu=%d ri=%d", cpu, ri);
285 	powerpc_set_pmc(cpu, ri, PMCN_NONE);
286 	return (0);
287 }
288 
289 int
290 powerpc_config_pmc(int cpu, int ri, struct pmc *pm)
291 {
292 	struct pmc_hw *phw;
293 
294 	PMCDBG3(MDP,CFG,1, "powerpc-config cpu=%d ri=%d pm=%p", cpu, ri, pm);
295 
296 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
297 	    ("[powerpc,%d] illegal CPU value %d", __LINE__, cpu));
298 	KASSERT(ri >= 0 && ri < ppc_max_pmcs,
299 	    ("[powerpc,%d] illegal row-index %d", __LINE__, ri));
300 
301 	phw = &powerpc_pcpu[cpu]->pc_ppcpmcs[ri];
302 
303 	KASSERT(pm == NULL || phw->phw_pmc == NULL,
304 	    ("[powerpc,%d] pm=%p phw->pm=%p hwpmc not unconfigured",
305 	    __LINE__, pm, phw->phw_pmc));
306 
307 	phw->phw_pmc = pm;
308 
309 	return (0);
310 }
311 
312 pmc_value_t
313 powerpc_pmcn_read_default(unsigned int pmc)
314 {
315 	pmc_value_t val;
316 
317 	if (pmc > ppc_max_pmcs)
318 		panic("Invalid PMC number: %d\n", pmc);
319 
320 	switch (pmc) {
321 	case 0:
322 		val = mfspr(SPR_PMC1);
323 		break;
324 	case 1:
325 		val = mfspr(SPR_PMC2);
326 		break;
327 	case 2:
328 		val = mfspr(SPR_PMC3);
329 		break;
330 	case 3:
331 		val = mfspr(SPR_PMC4);
332 		break;
333 	case 4:
334 		val = mfspr(SPR_PMC5);
335 		break;
336 	case 5:
337 		val = mfspr(SPR_PMC6);
338 		break;
339 	case 6:
340 		val = mfspr(SPR_PMC7);
341 		break;
342 	case 7:
343 		val = mfspr(SPR_PMC8);
344 		break;
345 	}
346 
347 	return (val);
348 }
349 
350 void
351 powerpc_pmcn_write_default(unsigned int pmc, uint32_t val)
352 {
353 	if (pmc > ppc_max_pmcs)
354 		panic("Invalid PMC number: %d\n", pmc);
355 
356 	switch (pmc) {
357 	case 0:
358 		mtspr(SPR_PMC1, val);
359 		break;
360 	case 1:
361 		mtspr(SPR_PMC2, val);
362 		break;
363 	case 2:
364 		mtspr(SPR_PMC3, val);
365 		break;
366 	case 3:
367 		mtspr(SPR_PMC4, val);
368 		break;
369 	case 4:
370 		mtspr(SPR_PMC5, val);
371 		break;
372 	case 5:
373 		mtspr(SPR_PMC6, val);
374 		break;
375 	case 6:
376 		mtspr(SPR_PMC7, val);
377 		break;
378 	case 7:
379 		mtspr(SPR_PMC8, val);
380 		break;
381 	}
382 }
383 
384 int
385 powerpc_read_pmc(int cpu, int ri, pmc_value_t *v)
386 {
387 	struct pmc *pm;
388 	pmc_value_t p, r, tmp;
389 
390 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
391 	    ("[powerpc,%d] illegal CPU value %d", __LINE__, cpu));
392 	KASSERT(ri >= 0 && ri < ppc_max_pmcs,
393 	    ("[powerpc,%d] illegal row index %d", __LINE__, ri));
394 
395 	pm  = powerpc_pcpu[cpu]->pc_ppcpmcs[ri].phw_pmc;
396 	KASSERT(pm,
397 	    ("[core,%d] cpu %d ri %d pmc not configured", __LINE__, cpu,
398 		ri));
399 
400 	/*
401 	 * After an interrupt occurs because of a PMC overflow, the PMC value
402 	 * is not always MAX_PMC_VALUE + 1, but may be a little above it.
403 	 * This may mess up calculations and frustrate machine independent
404 	 * layer expectations, such as that no value read should be greater
405 	 * than reload count in sampling mode.
406 	 * To avoid these issues, use MAX_PMC_VALUE as an upper limit.
407 	 */
408 	p = MIN(powerpc_pmcn_read(ri), POWERPC_MAX_PMC_VALUE);
409 	r = pm->pm_sc.pm_reloadcount;
410 
411 	if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm))) {
412 		/*
413 		 * Special case 1: r is too big
414 		 * This usually happens when a PMC write fails, the PMC is
415 		 * stopped and then it is read.
416 		 *
417 		 * Special case 2: PMC was reseted or has a value
418 		 * that should not be possible with current r.
419 		 *
420 		 * In the above cases, just return 0 instead of an arbitrary
421 		 * value.
422 		 */
423 		if (r > POWERPC_MAX_PMC_VALUE || p + r <= POWERPC_MAX_PMC_VALUE)
424 			tmp = 0;
425 		else
426 			tmp = POWERPC_PERFCTR_VALUE_TO_RELOAD_COUNT(p);
427 	} else
428 		tmp = p + (POWERPC_MAX_PMC_VALUE + 1) * PPC_OVERFLOWCNT(pm);
429 
430 	PMCDBG5(MDP,REA,1,"ppc-read cpu=%d ri=%d -> %jx (%jx,%jx)",
431 	    cpu, ri, (uintmax_t)tmp, (uintmax_t)PPC_OVERFLOWCNT(pm),
432 	    (uintmax_t)p);
433 	*v = tmp;
434 	return (0);
435 }
436 
437 int
438 powerpc_write_pmc(int cpu, int ri, pmc_value_t v)
439 {
440 	struct pmc *pm;
441 	pmc_value_t vlo;
442 
443 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
444 	    ("[powerpc,%d] illegal CPU value %d", __LINE__, cpu));
445 	KASSERT(ri >= 0 && ri < ppc_max_pmcs,
446 	    ("[powerpc,%d] illegal row-index %d", __LINE__, ri));
447 
448 	pm = powerpc_pcpu[cpu]->pc_ppcpmcs[ri].phw_pmc;
449 
450 	if (PMC_IS_COUNTING_MODE(PMC_TO_MODE(pm))) {
451 		PPC_OVERFLOWCNT(pm) = v / (POWERPC_MAX_PMC_VALUE + 1);
452 		vlo = v % (POWERPC_MAX_PMC_VALUE + 1);
453 	} else if (v > POWERPC_MAX_PMC_VALUE) {
454 		PMCDBG3(MDP,WRI,2,
455 		    "powerpc-write cpu=%d ri=%d: PMC value is too big: %jx",
456 		    cpu, ri, (uintmax_t)v);
457 		return (EINVAL);
458 	} else
459 		vlo = POWERPC_RELOAD_COUNT_TO_PERFCTR_VALUE(v);
460 
461 	PMCDBG5(MDP,WRI,1,"powerpc-write cpu=%d ri=%d -> %jx (%jx,%jx)",
462 	    cpu, ri, (uintmax_t)v, (uintmax_t)PPC_OVERFLOWCNT(pm),
463 	    (uintmax_t)vlo);
464 
465 	powerpc_pmcn_write(ri, vlo);
466 	return (0);
467 }
468 
469 int
470 powerpc_pmc_intr(struct trapframe *tf)
471 {
472 	struct pmc *pm;
473 	struct powerpc_cpu *pc;
474 	int cpu, error, i, retval;
475 
476 	cpu = curcpu;
477 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
478 	    ("[powerpc,%d] out of range CPU %d", __LINE__, cpu));
479 
480 	PMCDBG3(MDP,INT,1, "cpu=%d tf=%p um=%d", cpu, (void *) tf,
481 	    TRAPF_USERMODE(tf));
482 
483 	retval = 0;
484 	pc = powerpc_pcpu[cpu];
485 
486 	/*
487 	 * Look for a running, sampling PMC which has overflowed
488 	 * and which has a valid 'struct pmc' association.
489 	 */
490 	for (i = 0; i < ppc_max_pmcs; i++) {
491 		if (!POWERPC_PMC_HAS_OVERFLOWED(i))
492 			continue;
493 		retval = 1;	/* Found an interrupting PMC. */
494 
495 		/*
496 		 * Always clear the PMC, to make it stop interrupting.
497 		 * If pm is available and in sampling mode, use reload
498 		 * count, to make PMC read after stop correct.
499 		 * Otherwise, just reset the PMC.
500 		 */
501 		if ((pm = pc->pc_ppcpmcs[i].phw_pmc) != NULL &&
502 		    PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm))) {
503 			if (pm->pm_state != PMC_STATE_RUNNING) {
504 				powerpc_write_pmc(cpu, i,
505 				    pm->pm_sc.pm_reloadcount);
506 				continue;
507 			}
508 		} else {
509 			if (pm != NULL) { /* !PMC_IS_SAMPLING_MODE */
510 				PPC_OVERFLOWCNT(pm) = (PPC_OVERFLOWCNT(pm) +
511 				    1) % PPC_OVERFLOWCNT_MAX;
512 				PMCDBG3(MDP,INT,2,
513 				    "cpu=%d ri=%d: overflowcnt=%d",
514 				    cpu, i, PPC_OVERFLOWCNT(pm));
515 			}
516 
517 			powerpc_pmcn_write(i, 0);
518 			continue;
519 		}
520 
521 		error = pmc_process_interrupt(PMC_HR, pm, tf);
522 		if (error != 0) {
523 			PMCDBG3(MDP,INT,3,
524 			    "cpu=%d ri=%d: error %d processing interrupt",
525 			    cpu, i, error);
526 			powerpc_stop_pmc(cpu, i);
527 		}
528 
529 		/* Reload sampling count */
530 		powerpc_write_pmc(cpu, i, pm->pm_sc.pm_reloadcount);
531 	}
532 
533 	if (retval)
534 		counter_u64_add(pmc_stats.pm_intr_processed, 1);
535 	else
536 		counter_u64_add(pmc_stats.pm_intr_ignored, 1);
537 
538 	/*
539 	 * Re-enable PERF exceptions if we were able to find the interrupt
540 	 * source and handle it. Otherwise, it's better to disable PERF
541 	 * interrupts, to avoid the risk of processing the same interrupt
542 	 * forever.
543 	 */
544 	powerpc_resume_pmc(retval != 0);
545 	if (retval == 0)
546 		log(LOG_WARNING,
547 		    "pmc_intr: couldn't find interrupting PMC on cpu %d - "
548 		    "disabling PERF interrupts\n", cpu);
549 
550 	return (retval);
551 }
552 
553 struct pmc_mdep *
554 pmc_md_initialize()
555 {
556 	struct pmc_mdep *pmc_mdep;
557 	int error;
558 	uint16_t vers;
559 
560 	/*
561 	 * Allocate space for pointers to PMC HW descriptors and for
562 	 * the MDEP structure used by MI code.
563 	 */
564 	powerpc_pcpu = malloc(sizeof(struct powerpc_cpu *) * pmc_cpu_max(), M_PMC,
565 			   M_WAITOK|M_ZERO);
566 
567 	/* Just one class */
568 	pmc_mdep = pmc_mdep_alloc(1);
569 
570 	vers = mfpvr() >> 16;
571 
572 	pmc_mdep->pmd_switch_in  = powerpc_switch_in;
573 	pmc_mdep->pmd_switch_out = powerpc_switch_out;
574 
575 	switch (vers) {
576 	case MPC7447A:
577 	case MPC7448:
578 	case MPC7450:
579 	case MPC7455:
580 	case MPC7457:
581 		error = pmc_mpc7xxx_initialize(pmc_mdep);
582 		break;
583 	case IBM970:
584 	case IBM970FX:
585 	case IBM970MP:
586 		error = pmc_ppc970_initialize(pmc_mdep);
587 		break;
588 	case IBMPOWER8E:
589 	case IBMPOWER8NVL:
590 	case IBMPOWER8:
591 	case IBMPOWER9:
592 		error = pmc_power8_initialize(pmc_mdep);
593 		break;
594 	case FSL_E500v1:
595 	case FSL_E500v2:
596 	case FSL_E500mc:
597 	case FSL_E5500:
598 		error = pmc_e500_initialize(pmc_mdep);
599 		break;
600 	default:
601 		error = -1;
602 		break;
603 	}
604 
605 	if (error != 0) {
606 		pmc_mdep_free(pmc_mdep);
607 		pmc_mdep = NULL;
608 	}
609 
610 	/* Set the value for kern.hwpmc.cpuid */
611 	snprintf(pmc_cpuid, sizeof(pmc_cpuid), "%08x", mfpvr());
612 
613 	return (pmc_mdep);
614 }
615 
616 void
617 pmc_md_finalize(struct pmc_mdep *md)
618 {
619 
620 	free(powerpc_pcpu, M_PMC);
621 	powerpc_pcpu = NULL;
622 }
623 
624 int
625 pmc_save_user_callchain(uintptr_t *cc, int maxsamples,
626     struct trapframe *tf)
627 {
628 	uintptr_t *osp, *sp;
629 	int frames = 0;
630 
631 	cc[frames++] = PMC_TRAPFRAME_TO_PC(tf);
632 	sp = (uintptr_t *)PMC_TRAPFRAME_TO_FP(tf);
633 	osp = NULL;
634 
635 	for (; frames < maxsamples; frames++) {
636 		if (sp <= osp)
637 			break;
638 		osp = sp;
639 #ifdef __powerpc64__
640 		/* Check if 32-bit mode. */
641 		if (!(tf->srr1 & PSL_SF)) {
642 			cc[frames] = fuword32((uint32_t *)sp + 1);
643 			sp = (uintptr_t *)(uintptr_t)fuword32(sp);
644 		} else {
645 			cc[frames] = fuword(sp + 2);
646 			sp = (uintptr_t *)fuword(sp);
647 		}
648 #else
649 		cc[frames] = fuword32((uint32_t *)sp + 1);
650 		sp = (uintptr_t *)fuword32(sp);
651 #endif
652 	}
653 
654 	return (frames);
655 }
656