xref: /freebsd/sys/dev/hwpmc/hwpmc_powerpc.c (revision c66ec88fed842fbaad62c30d510644ceb7bd2d71)
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 
63 void (*powerpc_set_pmc)(int cpu, int ri, int config);
64 pmc_value_t (*powerpc_pmcn_read)(unsigned int pmc);
65 void (*powerpc_pmcn_write)(unsigned int pmc, uint32_t val);
66 void (*powerpc_resume_pmc)(bool ie);
67 
68 
69 int
70 pmc_save_kernel_callchain(uintptr_t *cc, int maxsamples,
71     struct trapframe *tf)
72 {
73 	uintptr_t *osp, *sp;
74 	uintptr_t pc;
75 	int frames = 0;
76 
77 	cc[frames++] = PMC_TRAPFRAME_TO_PC(tf);
78 	sp = (uintptr_t *)PMC_TRAPFRAME_TO_FP(tf);
79 	osp = (uintptr_t *)PAGE_SIZE;
80 
81 	for (; frames < maxsamples; frames++) {
82 		if (sp <= osp)
83 			break;
84 	    #ifdef __powerpc64__
85 		pc = sp[2];
86 	    #else
87 		pc = sp[1];
88 	    #endif
89 		if ((pc & 3) || (pc < 0x100))
90 			break;
91 
92 		/*
93 		 * trapexit() and asttrapexit() are sentinels
94 		 * for kernel stack tracing.
95 		 * */
96 		if (pc + OFFSET == (uintptr_t) &trapexit ||
97 		    pc + OFFSET == (uintptr_t) &asttrapexit)
98 			break;
99 
100 		cc[frames] = pc;
101 		osp = sp;
102 		sp = (uintptr_t *)*sp;
103 	}
104 	return (frames);
105 }
106 
107 static int
108 powerpc_switch_in(struct pmc_cpu *pc, struct pmc_process *pp)
109 {
110 
111 	return (0);
112 }
113 
114 static int
115 powerpc_switch_out(struct pmc_cpu *pc, struct pmc_process *pp)
116 {
117 
118 	return (0);
119 }
120 
121 int
122 powerpc_describe(int cpu, int ri, struct pmc_info *pi, struct pmc **ppmc)
123 {
124 	int error;
125 	struct pmc_hw *phw;
126 	char powerpc_name[PMC_NAME_MAX];
127 
128 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
129 	    ("[powerpc,%d], illegal CPU %d", __LINE__, cpu));
130 
131 	phw = &powerpc_pcpu[cpu]->pc_ppcpmcs[ri];
132 	snprintf(powerpc_name, sizeof(powerpc_name), "POWERPC-%d", ri);
133 	if ((error = copystr(powerpc_name, pi->pm_name, PMC_NAME_MAX,
134 	    NULL)) != 0)
135 		return error;
136 	pi->pm_class = powerpc_pcpu[cpu]->pc_class;
137 	if (phw->phw_state & PMC_PHW_FLAG_IS_ENABLED) {
138 		pi->pm_enabled = TRUE;
139 		*ppmc          = phw->phw_pmc;
140 	} else {
141 		pi->pm_enabled = FALSE;
142 		*ppmc	       = NULL;
143 	}
144 
145 	return (0);
146 }
147 
148 int
149 powerpc_get_config(int cpu, int ri, struct pmc **ppm)
150 {
151 
152 	*ppm = powerpc_pcpu[cpu]->pc_ppcpmcs[ri].phw_pmc;
153 
154 	return (0);
155 }
156 
157 int
158 powerpc_pcpu_init(struct pmc_mdep *md, int cpu)
159 {
160 	struct pmc_cpu *pc;
161 	struct powerpc_cpu *pac;
162 	struct pmc_hw  *phw;
163 	int first_ri, i;
164 
165 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
166 	    ("[powerpc,%d] wrong cpu number %d", __LINE__, cpu));
167 	PMCDBG1(MDP,INI,1,"powerpc-init cpu=%d", cpu);
168 
169 	powerpc_pcpu[cpu] = pac = malloc(sizeof(struct powerpc_cpu), M_PMC,
170 	    M_WAITOK|M_ZERO);
171 	pac->pc_ppcpmcs = malloc(sizeof(struct pmc_hw) * ppc_max_pmcs,
172 	    M_PMC, M_WAITOK|M_ZERO);
173 	pac->pc_class =
174 	    md->pmd_classdep[PMC_MDEP_CLASS_INDEX_POWERPC].pcd_class;
175 
176 	pc = pmc_pcpu[cpu];
177 	first_ri = md->pmd_classdep[PMC_MDEP_CLASS_INDEX_POWERPC].pcd_ri;
178 	KASSERT(pc != NULL, ("[powerpc,%d] NULL per-cpu pointer", __LINE__));
179 
180 	for (i = 0, phw = pac->pc_ppcpmcs; i < ppc_max_pmcs; i++, phw++) {
181 		phw->phw_state = PMC_PHW_FLAG_IS_ENABLED |
182 		    PMC_PHW_CPU_TO_STATE(cpu) | PMC_PHW_INDEX_TO_STATE(i);
183 		phw->phw_pmc = NULL;
184 		pc->pc_hwpmcs[i + first_ri] = phw;
185 	}
186 
187 	return (0);
188 }
189 
190 int
191 powerpc_pcpu_fini(struct pmc_mdep *md, int cpu)
192 {
193 	PMCDBG1(MDP,INI,1,"powerpc-fini cpu=%d", cpu);
194 
195 	free(powerpc_pcpu[cpu]->pc_ppcpmcs, M_PMC);
196 	free(powerpc_pcpu[cpu], M_PMC);
197 
198 	return (0);
199 }
200 
201 int
202 powerpc_allocate_pmc(int cpu, int ri, struct pmc *pm,
203     const struct pmc_op_pmcallocate *a)
204 {
205 	enum pmc_event pe;
206 	uint32_t caps, config = 0, counter = 0;
207 	int i;
208 
209 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
210 	    ("[powerpc,%d] illegal CPU value %d", __LINE__, cpu));
211 	KASSERT(ri >= 0 && ri < ppc_max_pmcs,
212 	    ("[powerpc,%d] illegal row index %d", __LINE__, ri));
213 
214 	caps = a->pm_caps;
215 
216 	pe = a->pm_ev;
217 
218 	if (pe < ppc_event_first || pe > ppc_event_last)
219 		return (EINVAL);
220 
221 	for (i = 0; i < ppc_event_codes_size; i++) {
222 		if (ppc_event_codes[i].pe_event == pe) {
223 			config = ppc_event_codes[i].pe_code;
224 			counter =  ppc_event_codes[i].pe_flags;
225 			break;
226 		}
227 	}
228 	if (i == ppc_event_codes_size)
229 		return (EINVAL);
230 
231 	if ((counter & (1 << ri)) == 0)
232 		return (EINVAL);
233 
234 	if (caps & PMC_CAP_SYSTEM)
235 		config |= POWERPC_PMC_KERNEL_ENABLE;
236 	if (caps & PMC_CAP_USER)
237 		config |= POWERPC_PMC_USER_ENABLE;
238 	if ((caps & (PMC_CAP_USER | PMC_CAP_SYSTEM)) == 0)
239 		config |= POWERPC_PMC_ENABLE;
240 
241 	pm->pm_md.pm_powerpc.pm_powerpc_evsel = config;
242 
243 	PMCDBG3(MDP,ALL,1,"powerpc-allocate cpu=%d ri=%d -> config=0x%x",
244 	    cpu, ri, config);
245 	return (0);
246 }
247 
248 int
249 powerpc_release_pmc(int cpu, int ri, struct pmc *pmc)
250 {
251 	struct pmc_hw *phw;
252 
253 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
254 	    ("[powerpc,%d] illegal CPU value %d", __LINE__, cpu));
255 	KASSERT(ri >= 0 && ri < ppc_max_pmcs,
256 	    ("[powerpc,%d] illegal row-index %d", __LINE__, ri));
257 
258 	phw = &powerpc_pcpu[cpu]->pc_ppcpmcs[ri];
259 	KASSERT(phw->phw_pmc == NULL,
260 	    ("[powerpc,%d] PHW pmc %p non-NULL", __LINE__, phw->phw_pmc));
261 
262 	return (0);
263 }
264 
265 int
266 powerpc_start_pmc(int cpu, int ri)
267 {
268 	struct pmc *pm;
269 
270 	PMCDBG2(MDP,STA,1,"powerpc-start cpu=%d ri=%d", cpu, ri);
271 	pm = powerpc_pcpu[cpu]->pc_ppcpmcs[ri].phw_pmc;
272 	powerpc_set_pmc(cpu, ri, pm->pm_md.pm_powerpc.pm_powerpc_evsel);
273 
274 	return (0);
275 }
276 
277 int
278 powerpc_stop_pmc(int cpu, int ri)
279 {
280 	PMCDBG2(MDP,STO,1, "powerpc-stop cpu=%d ri=%d", cpu, ri);
281 	powerpc_set_pmc(cpu, ri, PMCN_NONE);
282 	return (0);
283 }
284 
285 int
286 powerpc_config_pmc(int cpu, int ri, struct pmc *pm)
287 {
288 	struct pmc_hw *phw;
289 
290 	PMCDBG3(MDP,CFG,1, "powerpc-config cpu=%d ri=%d pm=%p", cpu, ri, pm);
291 
292 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
293 	    ("[powerpc,%d] illegal CPU value %d", __LINE__, cpu));
294 	KASSERT(ri >= 0 && ri < ppc_max_pmcs,
295 	    ("[powerpc,%d] illegal row-index %d", __LINE__, ri));
296 
297 	phw = &powerpc_pcpu[cpu]->pc_ppcpmcs[ri];
298 
299 	KASSERT(pm == NULL || phw->phw_pmc == NULL,
300 	    ("[powerpc,%d] pm=%p phw->pm=%p hwpmc not unconfigured",
301 	    __LINE__, pm, phw->phw_pmc));
302 
303 	phw->phw_pmc = pm;
304 
305 	return (0);
306 }
307 
308 pmc_value_t
309 powerpc_pmcn_read_default(unsigned int pmc)
310 {
311 	pmc_value_t val;
312 
313 	if (pmc > ppc_max_pmcs)
314 		panic("Invalid PMC number: %d\n", pmc);
315 
316 	switch (pmc) {
317 	case 0:
318 		val = mfspr(SPR_PMC1);
319 		break;
320 	case 1:
321 		val = mfspr(SPR_PMC2);
322 		break;
323 	case 2:
324 		val = mfspr(SPR_PMC3);
325 		break;
326 	case 3:
327 		val = mfspr(SPR_PMC4);
328 		break;
329 	case 4:
330 		val = mfspr(SPR_PMC5);
331 		break;
332 	case 5:
333 		val = mfspr(SPR_PMC6);
334 		break;
335 	case 6:
336 		val = mfspr(SPR_PMC7);
337 		break;
338 	case 7:
339 		val = mfspr(SPR_PMC8);
340 		break;
341 	}
342 
343 	return (val);
344 }
345 
346 void
347 powerpc_pmcn_write_default(unsigned int pmc, uint32_t val)
348 {
349 	if (pmc > ppc_max_pmcs)
350 		panic("Invalid PMC number: %d\n", pmc);
351 
352 	switch (pmc) {
353 	case 0:
354 		mtspr(SPR_PMC1, val);
355 		break;
356 	case 1:
357 		mtspr(SPR_PMC2, val);
358 		break;
359 	case 2:
360 		mtspr(SPR_PMC3, val);
361 		break;
362 	case 3:
363 		mtspr(SPR_PMC4, val);
364 		break;
365 	case 4:
366 		mtspr(SPR_PMC5, val);
367 		break;
368 	case 5:
369 		mtspr(SPR_PMC6, val);
370 		break;
371 	case 6:
372 		mtspr(SPR_PMC7, val);
373 		break;
374 	case 7:
375 		mtspr(SPR_PMC8, val);
376 		break;
377 	}
378 }
379 
380 int
381 powerpc_read_pmc(int cpu, int ri, pmc_value_t *v)
382 {
383 	struct pmc *pm;
384 	pmc_value_t p, r, tmp;
385 
386 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
387 	    ("[powerpc,%d] illegal CPU value %d", __LINE__, cpu));
388 	KASSERT(ri >= 0 && ri < ppc_max_pmcs,
389 	    ("[powerpc,%d] illegal row index %d", __LINE__, ri));
390 
391 	pm  = powerpc_pcpu[cpu]->pc_ppcpmcs[ri].phw_pmc;
392 	KASSERT(pm,
393 	    ("[core,%d] cpu %d ri %d pmc not configured", __LINE__, cpu,
394 		ri));
395 
396 	/*
397 	 * After an interrupt occurs because of a PMC overflow, the PMC value
398 	 * is not always MAX_PMC_VALUE + 1, but may be a little above it.
399 	 * This may mess up calculations and frustrate machine independent
400 	 * layer expectations, such as that no value read should be greater
401 	 * than reload count in sampling mode.
402 	 * To avoid these issues, use MAX_PMC_VALUE as an upper limit.
403 	 */
404 	p = MIN(powerpc_pmcn_read(ri), POWERPC_MAX_PMC_VALUE);
405 	r = pm->pm_sc.pm_reloadcount;
406 
407 	if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm))) {
408 		/*
409 		 * Special case 1: r is too big
410 		 * This usually happens when a PMC write fails, the PMC is
411 		 * stopped and then it is read.
412 		 *
413 		 * Special case 2: PMC was reseted or has a value
414 		 * that should not be possible with current r.
415 		 *
416 		 * In the above cases, just return 0 instead of an arbitrary
417 		 * value.
418 		 */
419 		if (r > POWERPC_MAX_PMC_VALUE || p + r <= POWERPC_MAX_PMC_VALUE)
420 			tmp = 0;
421 		else
422 			tmp = POWERPC_PERFCTR_VALUE_TO_RELOAD_COUNT(p);
423 	} else
424 		tmp = p + (POWERPC_MAX_PMC_VALUE + 1) * PPC_OVERFLOWCNT(pm);
425 
426 	PMCDBG5(MDP,REA,1,"ppc-read cpu=%d ri=%d -> %jx (%jx,%jx)",
427 	    cpu, ri, (uintmax_t)tmp, (uintmax_t)PPC_OVERFLOWCNT(pm),
428 	    (uintmax_t)p);
429 	*v = tmp;
430 	return (0);
431 }
432 
433 int
434 powerpc_write_pmc(int cpu, int ri, pmc_value_t v)
435 {
436 	struct pmc *pm;
437 	pmc_value_t vlo;
438 
439 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
440 	    ("[powerpc,%d] illegal CPU value %d", __LINE__, cpu));
441 	KASSERT(ri >= 0 && ri < ppc_max_pmcs,
442 	    ("[powerpc,%d] illegal row-index %d", __LINE__, ri));
443 
444 	pm = powerpc_pcpu[cpu]->pc_ppcpmcs[ri].phw_pmc;
445 
446 	if (PMC_IS_COUNTING_MODE(PMC_TO_MODE(pm))) {
447 		PPC_OVERFLOWCNT(pm) = v / (POWERPC_MAX_PMC_VALUE + 1);
448 		vlo = v % (POWERPC_MAX_PMC_VALUE + 1);
449 	} else if (v > POWERPC_MAX_PMC_VALUE) {
450 		PMCDBG3(MDP,WRI,2,
451 		    "powerpc-write cpu=%d ri=%d: PMC value is too big: %jx",
452 		    cpu, ri, (uintmax_t)v);
453 		return (EINVAL);
454 	} else
455 		vlo = POWERPC_RELOAD_COUNT_TO_PERFCTR_VALUE(v);
456 
457 	PMCDBG5(MDP,WRI,1,"powerpc-write cpu=%d ri=%d -> %jx (%jx,%jx)",
458 	    cpu, ri, (uintmax_t)v, (uintmax_t)PPC_OVERFLOWCNT(pm),
459 	    (uintmax_t)vlo);
460 
461 	powerpc_pmcn_write(ri, vlo);
462 	return (0);
463 }
464 
465 int
466 powerpc_pmc_intr(struct trapframe *tf)
467 {
468 	struct pmc *pm;
469 	struct powerpc_cpu *pc;
470 	int cpu, error, i, retval;
471 
472 	cpu = curcpu;
473 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
474 	    ("[powerpc,%d] out of range CPU %d", __LINE__, cpu));
475 
476 	PMCDBG3(MDP,INT,1, "cpu=%d tf=%p um=%d", cpu, (void *) tf,
477 	    TRAPF_USERMODE(tf));
478 
479 	retval = 0;
480 	pc = powerpc_pcpu[cpu];
481 
482 	/*
483 	 * Look for a running, sampling PMC which has overflowed
484 	 * and which has a valid 'struct pmc' association.
485 	 */
486 	for (i = 0; i < ppc_max_pmcs; i++) {
487 		if (!POWERPC_PMC_HAS_OVERFLOWED(i))
488 			continue;
489 		retval = 1;	/* Found an interrupting PMC. */
490 
491 		/*
492 		 * Always clear the PMC, to make it stop interrupting.
493 		 * If pm is available and in sampling mode, use reload
494 		 * count, to make PMC read after stop correct.
495 		 * Otherwise, just reset the PMC.
496 		 */
497 		if ((pm = pc->pc_ppcpmcs[i].phw_pmc) != NULL &&
498 		    PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm))) {
499 			if (pm->pm_state != PMC_STATE_RUNNING) {
500 				powerpc_write_pmc(cpu, i,
501 				    pm->pm_sc.pm_reloadcount);
502 				continue;
503 			}
504 		} else {
505 			if (pm != NULL) { /* !PMC_IS_SAMPLING_MODE */
506 				PPC_OVERFLOWCNT(pm) = (PPC_OVERFLOWCNT(pm) +
507 				    1) % PPC_OVERFLOWCNT_MAX;
508 				PMCDBG3(MDP,INT,2,
509 				    "cpu=%d ri=%d: overflowcnt=%d",
510 				    cpu, i, PPC_OVERFLOWCNT(pm));
511 			}
512 
513 			powerpc_pmcn_write(i, 0);
514 			continue;
515 		}
516 
517 		error = pmc_process_interrupt(PMC_HR, pm, tf);
518 		if (error != 0) {
519 			PMCDBG3(MDP,INT,3,
520 			    "cpu=%d ri=%d: error %d processing interrupt",
521 			    cpu, i, error);
522 			powerpc_stop_pmc(cpu, i);
523 		}
524 
525 		/* Reload sampling count */
526 		powerpc_write_pmc(cpu, i, pm->pm_sc.pm_reloadcount);
527 	}
528 
529 	if (retval)
530 		counter_u64_add(pmc_stats.pm_intr_processed, 1);
531 	else
532 		counter_u64_add(pmc_stats.pm_intr_ignored, 1);
533 
534 	/*
535 	 * Re-enable PERF exceptions if we were able to find the interrupt
536 	 * source and handle it. Otherwise, it's better to disable PERF
537 	 * interrupts, to avoid the risk of processing the same interrupt
538 	 * forever.
539 	 */
540 	powerpc_resume_pmc(retval != 0);
541 	if (retval == 0)
542 		log(LOG_WARNING,
543 		    "pmc_intr: couldn't find interrupting PMC on cpu %d - "
544 		    "disabling PERF interrupts\n", cpu);
545 
546 	return (retval);
547 }
548 
549 struct pmc_mdep *
550 pmc_md_initialize()
551 {
552 	struct pmc_mdep *pmc_mdep;
553 	int error;
554 	uint16_t vers;
555 
556 	/*
557 	 * Allocate space for pointers to PMC HW descriptors and for
558 	 * the MDEP structure used by MI code.
559 	 */
560 	powerpc_pcpu = malloc(sizeof(struct powerpc_cpu *) * pmc_cpu_max(), M_PMC,
561 			   M_WAITOK|M_ZERO);
562 
563 	/* Just one class */
564 	pmc_mdep = pmc_mdep_alloc(1);
565 
566 	vers = mfpvr() >> 16;
567 
568 	pmc_mdep->pmd_switch_in  = powerpc_switch_in;
569 	pmc_mdep->pmd_switch_out = powerpc_switch_out;
570 
571 	switch (vers) {
572 	case MPC7447A:
573 	case MPC7448:
574 	case MPC7450:
575 	case MPC7455:
576 	case MPC7457:
577 		error = pmc_mpc7xxx_initialize(pmc_mdep);
578 		break;
579 	case IBM970:
580 	case IBM970FX:
581 	case IBM970MP:
582 		error = pmc_ppc970_initialize(pmc_mdep);
583 		break;
584 	case IBMPOWER8E:
585 	case IBMPOWER8NVL:
586 	case IBMPOWER8:
587 	case IBMPOWER9:
588 		error = pmc_power8_initialize(pmc_mdep);
589 		break;
590 	case FSL_E500v1:
591 	case FSL_E500v2:
592 	case FSL_E500mc:
593 	case FSL_E5500:
594 		error = pmc_e500_initialize(pmc_mdep);
595 		break;
596 	default:
597 		error = -1;
598 		break;
599 	}
600 
601 	if (error != 0) {
602 		pmc_mdep_free(pmc_mdep);
603 		pmc_mdep = NULL;
604 	}
605 
606 	return (pmc_mdep);
607 }
608 
609 void
610 pmc_md_finalize(struct pmc_mdep *md)
611 {
612 
613 	free(powerpc_pcpu, M_PMC);
614 	powerpc_pcpu = NULL;
615 }
616 
617 int
618 pmc_save_user_callchain(uintptr_t *cc, int maxsamples,
619     struct trapframe *tf)
620 {
621 	uintptr_t *osp, *sp;
622 	int frames = 0;
623 
624 	cc[frames++] = PMC_TRAPFRAME_TO_PC(tf);
625 	sp = (uintptr_t *)PMC_TRAPFRAME_TO_FP(tf);
626 	osp = NULL;
627 
628 	for (; frames < maxsamples; frames++) {
629 		if (sp <= osp)
630 			break;
631 		osp = sp;
632 #ifdef __powerpc64__
633 		/* Check if 32-bit mode. */
634 		if (!(tf->srr1 & PSL_SF)) {
635 			cc[frames] = fuword32((uint32_t *)sp + 1);
636 			sp = (uintptr_t *)(uintptr_t)fuword32(sp);
637 		} else {
638 			cc[frames] = fuword(sp + 2);
639 			sp = (uintptr_t *)fuword(sp);
640 		}
641 #else
642 		cc[frames] = fuword32((uint32_t *)sp + 1);
643 		sp = (uintptr_t *)fuword32(sp);
644 #endif
645 	}
646 
647 	return (frames);
648 }
649