xref: /freebsd/sys/dev/hwpmc/hwpmc_arm64.c (revision bdcbfde31e8e9b343f113a1956384bdf30d1ed62)
1 /*-
2  * Copyright (c) 2015 Ruslan Bukin <br@bsdpad.com>
3  * All rights reserved.
4  *
5  * This software was developed by the University of Cambridge Computer
6  * Laboratory with support from ARM Ltd.
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 #include <sys/cdefs.h>
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/pmc.h>
34 #include <sys/pmckern.h>
35 
36 #include <machine/pmc_mdep.h>
37 #include <machine/cpu.h>
38 
39 #include "opt_acpi.h"
40 
41 static int arm64_npmcs;
42 
43 struct arm64_event_code_map {
44 	enum pmc_event	pe_ev;
45 	uint8_t		pe_code;
46 };
47 
48 /*
49  * Per-processor information.
50  */
51 struct arm64_cpu {
52 	struct pmc_hw   *pc_arm64pmcs;
53 };
54 
55 static struct arm64_cpu **arm64_pcpu;
56 
57 /*
58  * Interrupt Enable Set Register
59  */
60 static __inline void
61 arm64_interrupt_enable(uint32_t pmc)
62 {
63 	uint32_t reg;
64 
65 	reg = (1 << pmc);
66 	WRITE_SPECIALREG(pmintenset_el1, reg);
67 
68 	isb();
69 }
70 
71 /*
72  * Interrupt Clear Set Register
73  */
74 static __inline void
75 arm64_interrupt_disable(uint32_t pmc)
76 {
77 	uint32_t reg;
78 
79 	reg = (1 << pmc);
80 	WRITE_SPECIALREG(pmintenclr_el1, reg);
81 
82 	isb();
83 }
84 
85 /*
86  * Counter Set Enable Register
87  */
88 static __inline void
89 arm64_counter_enable(unsigned int pmc)
90 {
91 	uint32_t reg;
92 
93 	reg = (1 << pmc);
94 	WRITE_SPECIALREG(pmcntenset_el0, reg);
95 
96 	isb();
97 }
98 
99 /*
100  * Counter Clear Enable Register
101  */
102 static __inline void
103 arm64_counter_disable(unsigned int pmc)
104 {
105 	uint32_t reg;
106 
107 	reg = (1 << pmc);
108 	WRITE_SPECIALREG(pmcntenclr_el0, reg);
109 
110 	isb();
111 }
112 
113 /*
114  * Performance Monitors Control Register
115  */
116 static uint32_t
117 arm64_pmcr_read(void)
118 {
119 	uint32_t reg;
120 
121 	reg = READ_SPECIALREG(pmcr_el0);
122 
123 	return (reg);
124 }
125 
126 static void
127 arm64_pmcr_write(uint32_t reg)
128 {
129 
130 	WRITE_SPECIALREG(pmcr_el0, reg);
131 
132 	isb();
133 }
134 
135 /*
136  * Performance Count Register N
137  */
138 static uint32_t
139 arm64_pmcn_read(unsigned int pmc)
140 {
141 
142 	KASSERT(pmc < arm64_npmcs, ("%s: illegal PMC number %d", __func__, pmc));
143 
144 	WRITE_SPECIALREG(pmselr_el0, pmc);
145 
146 	isb();
147 
148 	return (READ_SPECIALREG(pmxevcntr_el0));
149 }
150 
151 static void
152 arm64_pmcn_write(unsigned int pmc, uint32_t reg)
153 {
154 
155 	KASSERT(pmc < arm64_npmcs, ("%s: illegal PMC number %d", __func__, pmc));
156 
157 	WRITE_SPECIALREG(pmselr_el0, pmc);
158 	WRITE_SPECIALREG(pmxevcntr_el0, reg);
159 
160 	isb();
161 }
162 
163 static int
164 arm64_allocate_pmc(int cpu, int ri, struct pmc *pm,
165   const struct pmc_op_pmcallocate *a)
166 {
167 	uint32_t config;
168 	enum pmc_event pe;
169 
170 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
171 	    ("[arm64,%d] illegal CPU value %d", __LINE__, cpu));
172 	KASSERT(ri >= 0 && ri < arm64_npmcs,
173 	    ("[arm64,%d] illegal row index %d", __LINE__, ri));
174 
175 	if (a->pm_class != PMC_CLASS_ARMV8) {
176 		return (EINVAL);
177 	}
178 	pe = a->pm_ev;
179 
180 	if ((a->pm_flags & PMC_F_EV_PMU) != 0) {
181 		config = a->pm_md.pm_md_config;
182 	} else {
183 		config = (uint32_t)pe - PMC_EV_ARMV8_FIRST;
184 		if (config > (PMC_EV_ARMV8_LAST - PMC_EV_ARMV8_FIRST))
185 			return (EINVAL);
186 	}
187 
188 	switch (a->pm_caps & (PMC_CAP_SYSTEM | PMC_CAP_USER)) {
189 	case PMC_CAP_SYSTEM:
190 		config |= PMEVTYPER_U;
191 		break;
192 	case PMC_CAP_USER:
193 		config |= PMEVTYPER_P;
194 		break;
195 	default:
196 		/*
197 		 * Trace both USER and SYSTEM if none are specified
198 		 * (default setting) or if both flags are specified
199 		 * (user explicitly requested both qualifiers).
200 		 */
201 		break;
202 	}
203 
204 	pm->pm_md.pm_arm64.pm_arm64_evsel = config;
205 	PMCDBG2(MDP, ALL, 2, "arm64-allocate ri=%d -> config=0x%x", ri, config);
206 
207 	return (0);
208 }
209 
210 
211 static int
212 arm64_read_pmc(int cpu, int ri, struct pmc *pm, pmc_value_t *v)
213 {
214 	pmc_value_t tmp;
215 	register_t s;
216 	int reg;
217 
218 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
219 	    ("[arm64,%d] illegal CPU value %d", __LINE__, cpu));
220 	KASSERT(ri >= 0 && ri < arm64_npmcs,
221 	    ("[arm64,%d] illegal row index %d", __LINE__, ri));
222 
223 	/*
224 	 * Ensure we don't get interrupted while updating the overflow count.
225 	 */
226 	s = intr_disable();
227 	tmp = arm64_pmcn_read(ri);
228 	reg = (1 << ri);
229 	if ((READ_SPECIALREG(pmovsclr_el0) & reg) != 0) {
230 		/* Clear Overflow Flag */
231 		WRITE_SPECIALREG(pmovsclr_el0, reg);
232 		pm->pm_pcpu_state[cpu].pps_overflowcnt++;
233 
234 		/* Reread counter in case we raced. */
235 		tmp = arm64_pmcn_read(ri);
236 	}
237 	tmp += 0x100000000llu * pm->pm_pcpu_state[cpu].pps_overflowcnt;
238 	intr_restore(s);
239 
240 	PMCDBG2(MDP, REA, 2, "arm64-read id=%d -> %jd", ri, tmp);
241 	if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm))) {
242 		/*
243 		 * Clamp value to 0 if the counter just overflowed,
244 		 * otherwise the returned reload count would wrap to a
245 		 * huge value.
246 		 */
247 		if ((tmp & (1ull << 63)) == 0)
248 			tmp = 0;
249 		else
250 			tmp = ARMV8_PERFCTR_VALUE_TO_RELOAD_COUNT(tmp);
251 	}
252 	*v = tmp;
253 
254 	return (0);
255 }
256 
257 static int
258 arm64_write_pmc(int cpu, int ri, struct pmc *pm, pmc_value_t v)
259 {
260 
261 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
262 	    ("[arm64,%d] illegal CPU value %d", __LINE__, cpu));
263 	KASSERT(ri >= 0 && ri < arm64_npmcs,
264 	    ("[arm64,%d] illegal row-index %d", __LINE__, ri));
265 
266 	if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)))
267 		v = ARMV8_RELOAD_COUNT_TO_PERFCTR_VALUE(v);
268 
269 	PMCDBG3(MDP, WRI, 1, "arm64-write cpu=%d ri=%d v=%jx", cpu, ri, v);
270 
271 	pm->pm_pcpu_state[cpu].pps_overflowcnt = v >> 32;
272 	arm64_pmcn_write(ri, v);
273 
274 	return (0);
275 }
276 
277 static int
278 arm64_config_pmc(int cpu, int ri, struct pmc *pm)
279 {
280 	struct pmc_hw *phw;
281 
282 	PMCDBG3(MDP, CFG, 1, "cpu=%d ri=%d pm=%p", cpu, ri, pm);
283 
284 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
285 	    ("[arm64,%d] illegal CPU value %d", __LINE__, cpu));
286 	KASSERT(ri >= 0 && ri < arm64_npmcs,
287 	    ("[arm64,%d] illegal row-index %d", __LINE__, ri));
288 
289 	phw = &arm64_pcpu[cpu]->pc_arm64pmcs[ri];
290 
291 	KASSERT(pm == NULL || phw->phw_pmc == NULL,
292 	    ("[arm64,%d] pm=%p phw->pm=%p hwpmc not unconfigured",
293 	    __LINE__, pm, phw->phw_pmc));
294 
295 	phw->phw_pmc = pm;
296 
297 	return (0);
298 }
299 
300 static int
301 arm64_start_pmc(int cpu, int ri, struct pmc *pm)
302 {
303 	uint32_t config;
304 
305 	config = pm->pm_md.pm_arm64.pm_arm64_evsel;
306 
307 	/*
308 	 * Configure the event selection.
309 	 */
310 	WRITE_SPECIALREG(pmselr_el0, ri);
311 	WRITE_SPECIALREG(pmxevtyper_el0, config);
312 
313 	isb();
314 
315 	/*
316 	 * Enable the PMC.
317 	 */
318 	arm64_interrupt_enable(ri);
319 	arm64_counter_enable(ri);
320 
321 	return (0);
322 }
323 
324 static int
325 arm64_stop_pmc(int cpu, int ri, struct pmc *pm __unused)
326 {
327 	/*
328 	 * Disable the PMCs.
329 	 */
330 	arm64_counter_disable(ri);
331 	arm64_interrupt_disable(ri);
332 
333 	return (0);
334 }
335 
336 static int
337 arm64_release_pmc(int cpu, int ri, struct pmc *pmc)
338 {
339 	struct pmc_hw *phw __diagused;
340 
341 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
342 	    ("[arm64,%d] illegal CPU value %d", __LINE__, cpu));
343 	KASSERT(ri >= 0 && ri < arm64_npmcs,
344 	    ("[arm64,%d] illegal row-index %d", __LINE__, ri));
345 
346 	phw = &arm64_pcpu[cpu]->pc_arm64pmcs[ri];
347 	KASSERT(phw->phw_pmc == NULL,
348 	    ("[arm64,%d] PHW pmc %p non-NULL", __LINE__, phw->phw_pmc));
349 
350 	return (0);
351 }
352 
353 static int
354 arm64_intr(struct trapframe *tf)
355 {
356 	int retval, ri;
357 	struct pmc *pm;
358 	int error;
359 	int reg, cpu;
360 
361 	cpu = curcpu;
362 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
363 	    ("[arm64,%d] CPU %d out of range", __LINE__, cpu));
364 
365 	PMCDBG3(MDP,INT,1, "cpu=%d tf=%p um=%d", cpu, (void *)tf,
366 	    TRAPF_USERMODE(tf));
367 
368 	retval = 0;
369 
370 	for (ri = 0; ri < arm64_npmcs; ri++) {
371 		pm = arm64_pcpu[cpu]->pc_arm64pmcs[ri].phw_pmc;
372 		if (pm == NULL)
373 			continue;
374 		/* Check if counter is overflowed */
375 		reg = (1 << ri);
376 		if ((READ_SPECIALREG(pmovsclr_el0) & reg) == 0)
377 			continue;
378 		/* Clear Overflow Flag */
379 		WRITE_SPECIALREG(pmovsclr_el0, reg);
380 
381 		isb();
382 
383 		retval = 1; /* Found an interrupting PMC. */
384 
385 		pm->pm_pcpu_state[cpu].pps_overflowcnt += 1;
386 
387 		if (!PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)))
388 			continue;
389 
390 		if (pm->pm_state != PMC_STATE_RUNNING)
391 			continue;
392 
393 		error = pmc_process_interrupt(PMC_HR, pm, tf);
394 		if (error)
395 			arm64_stop_pmc(cpu, ri, pm);
396 
397 		/* Reload sampling count */
398 		arm64_write_pmc(cpu, ri, pm, pm->pm_sc.pm_reloadcount);
399 	}
400 
401 	return (retval);
402 }
403 
404 static int
405 arm64_describe(int cpu, int ri, struct pmc_info *pi, struct pmc **ppmc)
406 {
407 	struct pmc_hw *phw;
408 
409 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
410 	    ("[arm64,%d], illegal CPU %d", __LINE__, cpu));
411 	KASSERT(ri >= 0 && ri < arm64_npmcs,
412 	    ("[arm64,%d] row-index %d out of range", __LINE__, ri));
413 
414 	phw = &arm64_pcpu[cpu]->pc_arm64pmcs[ri];
415 
416 	snprintf(pi->pm_name, sizeof(pi->pm_name), "ARMV8-%d", ri);
417 	pi->pm_class = PMC_CLASS_ARMV8;
418 
419 	if (phw->phw_state & PMC_PHW_FLAG_IS_ENABLED) {
420 		pi->pm_enabled = TRUE;
421 		*ppmc = phw->phw_pmc;
422 	} else {
423 		pi->pm_enabled = FALSE;
424 		*ppmc = NULL;
425 	}
426 
427 	return (0);
428 }
429 
430 static int
431 arm64_get_config(int cpu, int ri, struct pmc **ppm)
432 {
433 
434 	*ppm = arm64_pcpu[cpu]->pc_arm64pmcs[ri].phw_pmc;
435 
436 	return (0);
437 }
438 
439 static int
440 arm64_pcpu_init(struct pmc_mdep *md, int cpu)
441 {
442 	struct arm64_cpu *pac;
443 	struct pmc_hw  *phw;
444 	struct pmc_cpu *pc;
445 	uint64_t pmcr;
446 	int first_ri;
447 	int i;
448 
449 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
450 	    ("[arm64,%d] wrong cpu number %d", __LINE__, cpu));
451 	PMCDBG0(MDP, INI, 1, "arm64-pcpu-init");
452 
453 	arm64_pcpu[cpu] = pac = malloc(sizeof(struct arm64_cpu), M_PMC,
454 	    M_WAITOK | M_ZERO);
455 
456 	pac->pc_arm64pmcs = malloc(sizeof(struct pmc_hw) * arm64_npmcs,
457 	    M_PMC, M_WAITOK | M_ZERO);
458 	pc = pmc_pcpu[cpu];
459 	first_ri = md->pmd_classdep[PMC_MDEP_CLASS_INDEX_ARMV8].pcd_ri;
460 	KASSERT(pc != NULL, ("[arm64,%d] NULL per-cpu pointer", __LINE__));
461 
462 	for (i = 0, phw = pac->pc_arm64pmcs; i < arm64_npmcs; i++, phw++) {
463 		phw->phw_state    = PMC_PHW_FLAG_IS_ENABLED |
464 		    PMC_PHW_CPU_TO_STATE(cpu) | PMC_PHW_INDEX_TO_STATE(i);
465 		phw->phw_pmc      = NULL;
466 		pc->pc_hwpmcs[i + first_ri] = phw;
467 	}
468 
469 	/*
470 	 * Disable all counters and overflow interrupts. Upon reset they are in
471 	 * an undefined state.
472 	 *
473 	 * Don't issue an isb here, just wait for the one in arm64_pmcr_write()
474 	 * to make the writes visible.
475 	 */
476 	WRITE_SPECIALREG(pmcntenclr_el0, 0xffffffff);
477 	WRITE_SPECIALREG(pmintenclr_el1, 0xffffffff);
478 
479 	/* Enable unit */
480 	pmcr = arm64_pmcr_read();
481 	pmcr |= PMCR_E;
482 	arm64_pmcr_write(pmcr);
483 
484 	return (0);
485 }
486 
487 static int
488 arm64_pcpu_fini(struct pmc_mdep *md, int cpu)
489 {
490 	uint32_t pmcr;
491 
492 	PMCDBG0(MDP, INI, 1, "arm64-pcpu-fini");
493 
494 	pmcr = arm64_pmcr_read();
495 	pmcr &= ~PMCR_E;
496 	arm64_pmcr_write(pmcr);
497 
498 	free(arm64_pcpu[cpu]->pc_arm64pmcs, M_PMC);
499 	free(arm64_pcpu[cpu], M_PMC);
500 	arm64_pcpu[cpu] = NULL;
501 
502 	return (0);
503 }
504 
505 struct pmc_mdep *
506 pmc_arm64_initialize(void)
507 {
508 	struct pmc_mdep *pmc_mdep;
509 	struct pmc_classdep *pcd;
510 	int classes, idcode, impcode;
511 	int reg;
512 	uint64_t midr;
513 
514 	reg = arm64_pmcr_read();
515 	arm64_npmcs = (reg & PMCR_N_MASK) >> PMCR_N_SHIFT;
516 	impcode = (reg & PMCR_IMP_MASK) >> PMCR_IMP_SHIFT;
517 	idcode = (reg & PMCR_IDCODE_MASK) >> PMCR_IDCODE_SHIFT;
518 
519 	PMCDBG1(MDP, INI, 1, "arm64-init npmcs=%d", arm64_npmcs);
520 
521 	/*
522 	 * Write the CPU model to kern.hwpmc.cpuid.
523 	 *
524 	 * We zero the variant and revision fields.
525 	 *
526 	 * TODO: how to handle differences between cores due to big.LITTLE?
527 	 * For now, just use MIDR from CPU 0.
528 	 */
529 	midr = (uint64_t)(pcpu_find(0)->pc_midr);
530 	midr &= ~(CPU_VAR_MASK | CPU_REV_MASK);
531 	snprintf(pmc_cpuid, sizeof(pmc_cpuid), "0x%016lx", midr);
532 
533 	/*
534 	 * Allocate space for pointers to PMC HW descriptors and for
535 	 * the MDEP structure used by MI code.
536 	 */
537 	arm64_pcpu = malloc(sizeof(struct arm64_cpu *) * pmc_cpu_max(),
538 		M_PMC, M_WAITOK | M_ZERO);
539 
540 	/* One AArch64 CPU class */
541 	classes = 1;
542 
543 #ifdef DEV_ACPI
544 	/* Query presence of optional classes and set max class. */
545 	if (pmc_cmn600_nclasses() > 0)
546 		classes = MAX(classes, PMC_MDEP_CLASS_INDEX_CMN600);
547 	if (pmc_dmc620_nclasses() > 0)
548 		classes = MAX(classes, PMC_MDEP_CLASS_INDEX_DMC620_C);
549 #endif
550 
551 	pmc_mdep = pmc_mdep_alloc(classes);
552 
553 	switch(impcode) {
554 	case PMCR_IMP_ARM:
555 		switch (idcode) {
556 		case PMCR_IDCODE_CORTEX_A76:
557 		case PMCR_IDCODE_NEOVERSE_N1:
558 			pmc_mdep->pmd_cputype = PMC_CPU_ARMV8_CORTEX_A76;
559 			break;
560 		case PMCR_IDCODE_CORTEX_A57:
561 		case PMCR_IDCODE_CORTEX_A72:
562 			pmc_mdep->pmd_cputype = PMC_CPU_ARMV8_CORTEX_A57;
563 			break;
564 		default:
565 		case PMCR_IDCODE_CORTEX_A53:
566 			pmc_mdep->pmd_cputype = PMC_CPU_ARMV8_CORTEX_A53;
567 			break;
568 		}
569 		break;
570 	default:
571 		pmc_mdep->pmd_cputype = PMC_CPU_ARMV8_CORTEX_A53;
572 		break;
573 	}
574 
575 	pcd = &pmc_mdep->pmd_classdep[PMC_MDEP_CLASS_INDEX_ARMV8];
576 	pcd->pcd_caps  = ARMV8_PMC_CAPS;
577 	pcd->pcd_class = PMC_CLASS_ARMV8;
578 	pcd->pcd_num   = arm64_npmcs;
579 	pcd->pcd_ri    = pmc_mdep->pmd_npmc;
580 	pcd->pcd_width = 32;
581 
582 	pcd->pcd_allocate_pmc   = arm64_allocate_pmc;
583 	pcd->pcd_config_pmc     = arm64_config_pmc;
584 	pcd->pcd_pcpu_fini      = arm64_pcpu_fini;
585 	pcd->pcd_pcpu_init      = arm64_pcpu_init;
586 	pcd->pcd_describe       = arm64_describe;
587 	pcd->pcd_get_config     = arm64_get_config;
588 	pcd->pcd_read_pmc       = arm64_read_pmc;
589 	pcd->pcd_release_pmc    = arm64_release_pmc;
590 	pcd->pcd_start_pmc      = arm64_start_pmc;
591 	pcd->pcd_stop_pmc       = arm64_stop_pmc;
592 	pcd->pcd_write_pmc      = arm64_write_pmc;
593 
594 	pmc_mdep->pmd_intr = arm64_intr;
595 	pmc_mdep->pmd_npmc += arm64_npmcs;
596 
597 #ifdef DEV_ACPI
598 	if (pmc_cmn600_nclasses() > 0)
599 		pmc_cmn600_initialize(pmc_mdep);
600 	if (pmc_dmc620_nclasses() > 0) {
601 		pmc_dmc620_initialize_cd2(pmc_mdep);
602 		pmc_dmc620_initialize_c(pmc_mdep);
603 	}
604 #endif
605 
606 	return (pmc_mdep);
607 }
608 
609 void
610 pmc_arm64_finalize(struct pmc_mdep *md)
611 {
612 	PMCDBG0(MDP, INI, 1, "arm64-finalize");
613 
614 	for (int i = 0; i < pmc_cpu_max(); i++)
615 		KASSERT(arm64_pcpu[i] == NULL,
616 		    ("[arm64,%d] non-null pcpu cpu %d", __LINE__, i));
617 
618 	free(arm64_pcpu, M_PMC);
619 }
620