xref: /freebsd/sys/dev/hwpmc/hwpmc_arm64.c (revision 3f9d360c82e0724bfb61346038236bf15c5d4d84)
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 __FBSDID("$FreeBSD$");
32 
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/pmc.h>
36 #include <sys/pmckern.h>
37 
38 #include <machine/pmc_mdep.h>
39 #include <machine/cpu.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 caps, config;
168 	struct arm64_cpu *pac;
169 	enum pmc_event pe;
170 
171 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
172 	    ("[arm64,%d] illegal CPU value %d", __LINE__, cpu));
173 	KASSERT(ri >= 0 && ri < arm64_npmcs,
174 	    ("[arm64,%d] illegal row index %d", __LINE__, ri));
175 
176 	pac = arm64_pcpu[cpu];
177 
178 	caps = a->pm_caps;
179 	if (a->pm_class != PMC_CLASS_ARMV8) {
180 		return (EINVAL);
181 	}
182 	pe = a->pm_ev;
183 
184 	/* Adjust the config value if needed. */
185 	config = a->pm_md.pm_md_config;
186 	if ((a->pm_md.pm_md_flags & PM_MD_RAW_EVENT) == 0) {
187 		config = (uint32_t)pe - PMC_EV_ARMV8_FIRST;
188 		if (config > (PMC_EV_ARMV8_LAST - PMC_EV_ARMV8_FIRST))
189 			return (EINVAL);
190 	}
191 	pm->pm_md.pm_arm64.pm_arm64_evsel = config;
192 	PMCDBG2(MDP, ALL, 2, "arm64-allocate ri=%d -> config=0x%x", ri, config);
193 
194 	return (0);
195 }
196 
197 
198 static int
199 arm64_read_pmc(int cpu, int ri, pmc_value_t *v)
200 {
201 	pmc_value_t tmp;
202 	struct pmc *pm;
203 	register_t s;
204 	int reg;
205 
206 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
207 	    ("[arm64,%d] illegal CPU value %d", __LINE__, cpu));
208 	KASSERT(ri >= 0 && ri < arm64_npmcs,
209 	    ("[arm64,%d] illegal row index %d", __LINE__, ri));
210 
211 	pm  = arm64_pcpu[cpu]->pc_arm64pmcs[ri].phw_pmc;
212 
213 	/*
214 	 * Ensure we don't get interrupted while updating the overflow count.
215 	 */
216 	s = intr_disable();
217 	tmp = arm64_pmcn_read(ri);
218 	reg = (1 << ri);
219 	if ((READ_SPECIALREG(pmovsclr_el0) & reg) != 0) {
220 		/* Clear Overflow Flag */
221 		WRITE_SPECIALREG(pmovsclr_el0, reg);
222 		if (!PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)))
223 			pm->pm_pcpu_state[cpu].pps_overflowcnt++;
224 
225 		/* Reread counter in case we raced. */
226 		tmp = arm64_pmcn_read(ri);
227 	}
228 	tmp += 0x100000000llu * pm->pm_pcpu_state[cpu].pps_overflowcnt;
229 	intr_restore(s);
230 
231 	PMCDBG2(MDP, REA, 2, "arm64-read id=%d -> %jd", ri, tmp);
232 	if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)))
233 		*v = ARMV8_PERFCTR_VALUE_TO_RELOAD_COUNT(tmp);
234 	else
235 		*v = tmp;
236 
237 	return (0);
238 }
239 
240 static int
241 arm64_write_pmc(int cpu, int ri, pmc_value_t v)
242 {
243 	struct pmc *pm;
244 
245 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
246 	    ("[arm64,%d] illegal CPU value %d", __LINE__, cpu));
247 	KASSERT(ri >= 0 && ri < arm64_npmcs,
248 	    ("[arm64,%d] illegal row-index %d", __LINE__, ri));
249 
250 	pm  = arm64_pcpu[cpu]->pc_arm64pmcs[ri].phw_pmc;
251 
252 	if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)))
253 		v = ARMV8_RELOAD_COUNT_TO_PERFCTR_VALUE(v);
254 
255 	PMCDBG3(MDP, WRI, 1, "arm64-write cpu=%d ri=%d v=%jx", cpu, ri, v);
256 
257 	pm->pm_pcpu_state[cpu].pps_overflowcnt = v >> 32;
258 	arm64_pmcn_write(ri, v);
259 
260 	return (0);
261 }
262 
263 static int
264 arm64_config_pmc(int cpu, int ri, struct pmc *pm)
265 {
266 	struct pmc_hw *phw;
267 
268 	PMCDBG3(MDP, CFG, 1, "cpu=%d ri=%d pm=%p", cpu, ri, pm);
269 
270 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
271 	    ("[arm64,%d] illegal CPU value %d", __LINE__, cpu));
272 	KASSERT(ri >= 0 && ri < arm64_npmcs,
273 	    ("[arm64,%d] illegal row-index %d", __LINE__, ri));
274 
275 	phw = &arm64_pcpu[cpu]->pc_arm64pmcs[ri];
276 
277 	KASSERT(pm == NULL || phw->phw_pmc == NULL,
278 	    ("[arm64,%d] pm=%p phw->pm=%p hwpmc not unconfigured",
279 	    __LINE__, pm, phw->phw_pmc));
280 
281 	phw->phw_pmc = pm;
282 
283 	return (0);
284 }
285 
286 static int
287 arm64_start_pmc(int cpu, int ri)
288 {
289 	struct pmc_hw *phw;
290 	uint32_t config;
291 	struct pmc *pm;
292 
293 	phw    = &arm64_pcpu[cpu]->pc_arm64pmcs[ri];
294 	pm     = phw->phw_pmc;
295 	config = pm->pm_md.pm_arm64.pm_arm64_evsel;
296 
297 	/*
298 	 * Configure the event selection.
299 	 */
300 	WRITE_SPECIALREG(pmselr_el0, ri);
301 	WRITE_SPECIALREG(pmxevtyper_el0, config);
302 
303 	isb();
304 
305 	/*
306 	 * Enable the PMC.
307 	 */
308 	arm64_interrupt_enable(ri);
309 	arm64_counter_enable(ri);
310 
311 	return (0);
312 }
313 
314 static int
315 arm64_stop_pmc(int cpu, int ri)
316 {
317 	struct pmc_hw *phw;
318 	struct pmc *pm;
319 
320 	phw    = &arm64_pcpu[cpu]->pc_arm64pmcs[ri];
321 	pm     = phw->phw_pmc;
322 
323 	/*
324 	 * Disable the PMCs.
325 	 */
326 	arm64_counter_disable(ri);
327 	arm64_interrupt_disable(ri);
328 
329 	return (0);
330 }
331 
332 static int
333 arm64_release_pmc(int cpu, int ri, struct pmc *pmc)
334 {
335 	struct pmc_hw *phw;
336 
337 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
338 	    ("[arm64,%d] illegal CPU value %d", __LINE__, cpu));
339 	KASSERT(ri >= 0 && ri < arm64_npmcs,
340 	    ("[arm64,%d] illegal row-index %d", __LINE__, ri));
341 
342 	phw = &arm64_pcpu[cpu]->pc_arm64pmcs[ri];
343 	KASSERT(phw->phw_pmc == NULL,
344 	    ("[arm64,%d] PHW pmc %p non-NULL", __LINE__, phw->phw_pmc));
345 
346 	return (0);
347 }
348 
349 static int
350 arm64_intr(struct trapframe *tf)
351 {
352 	struct arm64_cpu *pc;
353 	int retval, ri;
354 	struct pmc *pm;
355 	int error;
356 	int reg, cpu;
357 
358 	cpu = curcpu;
359 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
360 	    ("[arm64,%d] CPU %d out of range", __LINE__, cpu));
361 
362 	PMCDBG3(MDP,INT,1, "cpu=%d tf=%p um=%d", cpu, (void *)tf,
363 	    TRAPF_USERMODE(tf));
364 
365 	retval = 0;
366 	pc = arm64_pcpu[cpu];
367 
368 	for (ri = 0; ri < arm64_npmcs; ri++) {
369 		pm = arm64_pcpu[cpu]->pc_arm64pmcs[ri].phw_pmc;
370 		if (pm == NULL)
371 			continue;
372 		/* Check if counter is overflowed */
373 		reg = (1 << ri);
374 		if ((READ_SPECIALREG(pmovsclr_el0) & reg) == 0)
375 			continue;
376 		/* Clear Overflow Flag */
377 		WRITE_SPECIALREG(pmovsclr_el0, reg);
378 
379 		isb();
380 
381 		retval = 1; /* Found an interrupting PMC. */
382 
383 		if (!PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm))) {
384 			pm->pm_pcpu_state[cpu].pps_overflowcnt += 1;
385 			continue;
386 		}
387 
388 		if (pm->pm_state != PMC_STATE_RUNNING)
389 			continue;
390 
391 		error = pmc_process_interrupt(PMC_HR, pm, tf);
392 		if (error)
393 			arm64_stop_pmc(cpu, ri);
394 
395 		/* Reload sampling count */
396 		arm64_write_pmc(cpu, ri, pm->pm_sc.pm_reloadcount);
397 	}
398 
399 	return (retval);
400 }
401 
402 static int
403 arm64_describe(int cpu, int ri, struct pmc_info *pi, struct pmc **ppmc)
404 {
405 	char arm64_name[PMC_NAME_MAX];
406 	struct pmc_hw *phw;
407 	int error;
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 	snprintf(arm64_name, sizeof(arm64_name), "ARMV8-%d", ri);
416 	if ((error = copystr(arm64_name, pi->pm_name, PMC_NAME_MAX,
417 	    NULL)) != 0)
418 		return (error);
419 	pi->pm_class = PMC_CLASS_ARMV8;
420 	if (phw->phw_state & PMC_PHW_FLAG_IS_ENABLED) {
421 		pi->pm_enabled = TRUE;
422 		*ppmc = phw->phw_pmc;
423 	} else {
424 		pi->pm_enabled = FALSE;
425 		*ppmc = NULL;
426 	}
427 
428 	return (0);
429 }
430 
431 static int
432 arm64_get_config(int cpu, int ri, struct pmc **ppm)
433 {
434 
435 	*ppm = arm64_pcpu[cpu]->pc_arm64pmcs[ri].phw_pmc;
436 
437 	return (0);
438 }
439 
440 /*
441  * XXX don't know what we should do here.
442  */
443 static int
444 arm64_switch_in(struct pmc_cpu *pc, struct pmc_process *pp)
445 {
446 
447 	return (0);
448 }
449 
450 static int
451 arm64_switch_out(struct pmc_cpu *pc, struct pmc_process *pp)
452 {
453 
454 	return (0);
455 }
456 
457 static int
458 arm64_pcpu_init(struct pmc_mdep *md, int cpu)
459 {
460 	struct arm64_cpu *pac;
461 	struct pmc_hw  *phw;
462 	struct pmc_cpu *pc;
463 	uint64_t pmcr;
464 	int first_ri;
465 	int i;
466 
467 	KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
468 	    ("[arm64,%d] wrong cpu number %d", __LINE__, cpu));
469 	PMCDBG1(MDP, INI, 1, "arm64-init cpu=%d", cpu);
470 
471 	arm64_pcpu[cpu] = pac = malloc(sizeof(struct arm64_cpu), M_PMC,
472 	    M_WAITOK | M_ZERO);
473 
474 	pac->pc_arm64pmcs = malloc(sizeof(struct pmc_hw) * arm64_npmcs,
475 	    M_PMC, M_WAITOK | M_ZERO);
476 	pc = pmc_pcpu[cpu];
477 	first_ri = md->pmd_classdep[PMC_MDEP_CLASS_INDEX_ARMV8].pcd_ri;
478 	KASSERT(pc != NULL, ("[arm64,%d] NULL per-cpu pointer", __LINE__));
479 
480 	for (i = 0, phw = pac->pc_arm64pmcs; i < arm64_npmcs; i++, phw++) {
481 		phw->phw_state    = PMC_PHW_FLAG_IS_ENABLED |
482 		    PMC_PHW_CPU_TO_STATE(cpu) | PMC_PHW_INDEX_TO_STATE(i);
483 		phw->phw_pmc      = NULL;
484 		pc->pc_hwpmcs[i + first_ri] = phw;
485 	}
486 
487 	/* Enable unit */
488 	pmcr = arm64_pmcr_read();
489 	pmcr |= PMCR_E;
490 	arm64_pmcr_write(pmcr);
491 
492 	return (0);
493 }
494 
495 static int
496 arm64_pcpu_fini(struct pmc_mdep *md, int cpu)
497 {
498 	uint32_t pmcr;
499 
500 	pmcr = arm64_pmcr_read();
501 	pmcr &= ~PMCR_E;
502 	arm64_pmcr_write(pmcr);
503 
504 	return (0);
505 }
506 
507 struct pmc_mdep *
508 pmc_arm64_initialize()
509 {
510 	struct pmc_mdep *pmc_mdep;
511 	struct pmc_classdep *pcd;
512 	int idcode, impcode;
513 	int reg;
514 	uint64_t midr;
515 
516 	reg = arm64_pmcr_read();
517 	arm64_npmcs = (reg & PMCR_N_MASK) >> PMCR_N_SHIFT;
518 	impcode = (reg & PMCR_IMP_MASK) >> PMCR_IMP_SHIFT;
519 	idcode = (reg & PMCR_IDCODE_MASK) >> PMCR_IDCODE_SHIFT;
520 
521 	PMCDBG1(MDP, INI, 1, "arm64-init npmcs=%d", arm64_npmcs);
522 
523 	/*
524 	 * Write the CPU model to kern.hwpmc.cpuid.
525 	 *
526 	 * We zero the variant and revision fields.
527 	 *
528 	 * TODO: how to handle differences between cores due to big.LITTLE?
529 	 * For now, just use MIDR from CPU 0.
530 	 */
531 	midr = (uint64_t)(pcpu_find(0)->pc_midr);
532 	midr &= ~(CPU_VAR_MASK | CPU_REV_MASK);
533 	snprintf(pmc_cpuid, sizeof(pmc_cpuid), "0x%016lx", midr);
534 
535 	/*
536 	 * Allocate space for pointers to PMC HW descriptors and for
537 	 * the MDEP structure used by MI code.
538 	 */
539 	arm64_pcpu = malloc(sizeof(struct arm64_cpu *) * pmc_cpu_max(),
540 		M_PMC, M_WAITOK | M_ZERO);
541 
542 	/* Just one class */
543 	pmc_mdep = pmc_mdep_alloc(1);
544 
545 	switch(impcode) {
546 	case PMCR_IMP_ARM:
547 		switch (idcode) {
548 		case PMCR_IDCODE_CORTEX_A76:
549 		case PMCR_IDCODE_NEOVERSE_N1:
550 			pmc_mdep->pmd_cputype = PMC_CPU_ARMV8_CORTEX_A76;
551 			break;
552 		case PMCR_IDCODE_CORTEX_A57:
553 		case PMCR_IDCODE_CORTEX_A72:
554 			pmc_mdep->pmd_cputype = PMC_CPU_ARMV8_CORTEX_A57;
555 			break;
556 		default:
557 		case PMCR_IDCODE_CORTEX_A53:
558 			pmc_mdep->pmd_cputype = PMC_CPU_ARMV8_CORTEX_A53;
559 			break;
560 		}
561 		break;
562 	default:
563 		pmc_mdep->pmd_cputype = PMC_CPU_ARMV8_CORTEX_A53;
564 		break;
565 	}
566 
567 	pcd = &pmc_mdep->pmd_classdep[PMC_MDEP_CLASS_INDEX_ARMV8];
568 	pcd->pcd_caps  = ARMV8_PMC_CAPS;
569 	pcd->pcd_class = PMC_CLASS_ARMV8;
570 	pcd->pcd_num   = arm64_npmcs;
571 	pcd->pcd_ri    = pmc_mdep->pmd_npmc;
572 	pcd->pcd_width = 32;
573 
574 	pcd->pcd_allocate_pmc   = arm64_allocate_pmc;
575 	pcd->pcd_config_pmc     = arm64_config_pmc;
576 	pcd->pcd_pcpu_fini      = arm64_pcpu_fini;
577 	pcd->pcd_pcpu_init      = arm64_pcpu_init;
578 	pcd->pcd_describe       = arm64_describe;
579 	pcd->pcd_get_config     = arm64_get_config;
580 	pcd->pcd_read_pmc       = arm64_read_pmc;
581 	pcd->pcd_release_pmc    = arm64_release_pmc;
582 	pcd->pcd_start_pmc      = arm64_start_pmc;
583 	pcd->pcd_stop_pmc       = arm64_stop_pmc;
584 	pcd->pcd_write_pmc      = arm64_write_pmc;
585 
586 	pmc_mdep->pmd_intr       = arm64_intr;
587 	pmc_mdep->pmd_switch_in  = arm64_switch_in;
588 	pmc_mdep->pmd_switch_out = arm64_switch_out;
589 
590 	pmc_mdep->pmd_npmc   += arm64_npmcs;
591 
592 	return (pmc_mdep);
593 }
594 
595 void
596 pmc_arm64_finalize(struct pmc_mdep *md)
597 {
598 
599 }
600