xref: /openbmc/linux/arch/arm/mach-imx/mmdc.c (revision d2ba09c1)
1 /*
2  * Copyright 2017 NXP
3  * Copyright 2011,2016 Freescale Semiconductor, Inc.
4  * Copyright 2011 Linaro Ltd.
5  *
6  * The code contained herein is licensed under the GNU General Public
7  * License. You may obtain a copy of the GNU General Public License
8  * Version 2 or later at the following locations:
9  *
10  * http://www.opensource.org/licenses/gpl-license.html
11  * http://www.gnu.org/copyleft/gpl.html
12  */
13 
14 #include <linux/hrtimer.h>
15 #include <linux/init.h>
16 #include <linux/interrupt.h>
17 #include <linux/io.h>
18 #include <linux/module.h>
19 #include <linux/of.h>
20 #include <linux/of_address.h>
21 #include <linux/of_device.h>
22 #include <linux/perf_event.h>
23 #include <linux/slab.h>
24 
25 #include "common.h"
26 
27 #define MMDC_MAPSR		0x404
28 #define BP_MMDC_MAPSR_PSD	0
29 #define BP_MMDC_MAPSR_PSS	4
30 
31 #define MMDC_MDMISC		0x18
32 #define BM_MMDC_MDMISC_DDR_TYPE	0x18
33 #define BP_MMDC_MDMISC_DDR_TYPE	0x3
34 
35 #define TOTAL_CYCLES		0x0
36 #define BUSY_CYCLES		0x1
37 #define READ_ACCESSES		0x2
38 #define WRITE_ACCESSES		0x3
39 #define READ_BYTES		0x4
40 #define WRITE_BYTES		0x5
41 
42 /* Enables, resets, freezes, overflow profiling*/
43 #define DBG_DIS			0x0
44 #define DBG_EN			0x1
45 #define DBG_RST			0x2
46 #define PRF_FRZ			0x4
47 #define CYC_OVF			0x8
48 #define PROFILE_SEL		0x10
49 
50 #define MMDC_MADPCR0	0x410
51 #define MMDC_MADPCR1	0x414
52 #define MMDC_MADPSR0	0x418
53 #define MMDC_MADPSR1	0x41C
54 #define MMDC_MADPSR2	0x420
55 #define MMDC_MADPSR3	0x424
56 #define MMDC_MADPSR4	0x428
57 #define MMDC_MADPSR5	0x42C
58 
59 #define MMDC_NUM_COUNTERS	6
60 
61 #define MMDC_FLAG_PROFILE_SEL	0x1
62 #define MMDC_PRF_AXI_ID_CLEAR	0x0
63 
64 #define to_mmdc_pmu(p) container_of(p, struct mmdc_pmu, pmu)
65 
66 static int ddr_type;
67 
68 struct fsl_mmdc_devtype_data {
69 	unsigned int flags;
70 };
71 
72 static const struct fsl_mmdc_devtype_data imx6q_data = {
73 };
74 
75 static const struct fsl_mmdc_devtype_data imx6qp_data = {
76 	.flags = MMDC_FLAG_PROFILE_SEL,
77 };
78 
79 static const struct of_device_id imx_mmdc_dt_ids[] = {
80 	{ .compatible = "fsl,imx6q-mmdc", .data = (void *)&imx6q_data},
81 	{ .compatible = "fsl,imx6qp-mmdc", .data = (void *)&imx6qp_data},
82 	{ /* sentinel */ }
83 };
84 
85 #ifdef CONFIG_PERF_EVENTS
86 
87 static enum cpuhp_state cpuhp_mmdc_state;
88 static DEFINE_IDA(mmdc_ida);
89 
90 PMU_EVENT_ATTR_STRING(total-cycles, mmdc_pmu_total_cycles, "event=0x00")
91 PMU_EVENT_ATTR_STRING(busy-cycles, mmdc_pmu_busy_cycles, "event=0x01")
92 PMU_EVENT_ATTR_STRING(read-accesses, mmdc_pmu_read_accesses, "event=0x02")
93 PMU_EVENT_ATTR_STRING(write-accesses, mmdc_pmu_write_accesses, "event=0x03")
94 PMU_EVENT_ATTR_STRING(read-bytes, mmdc_pmu_read_bytes, "event=0x04")
95 PMU_EVENT_ATTR_STRING(read-bytes.unit, mmdc_pmu_read_bytes_unit, "MB");
96 PMU_EVENT_ATTR_STRING(read-bytes.scale, mmdc_pmu_read_bytes_scale, "0.000001");
97 PMU_EVENT_ATTR_STRING(write-bytes, mmdc_pmu_write_bytes, "event=0x05")
98 PMU_EVENT_ATTR_STRING(write-bytes.unit, mmdc_pmu_write_bytes_unit, "MB");
99 PMU_EVENT_ATTR_STRING(write-bytes.scale, mmdc_pmu_write_bytes_scale, "0.000001");
100 
101 struct mmdc_pmu {
102 	struct pmu pmu;
103 	void __iomem *mmdc_base;
104 	cpumask_t cpu;
105 	struct hrtimer hrtimer;
106 	unsigned int active_events;
107 	struct device *dev;
108 	struct perf_event *mmdc_events[MMDC_NUM_COUNTERS];
109 	struct hlist_node node;
110 	struct fsl_mmdc_devtype_data *devtype_data;
111 };
112 
113 /*
114  * Polling period is set to one second, overflow of total-cycles (the fastest
115  * increasing counter) takes ten seconds so one second is safe
116  */
117 static unsigned int mmdc_pmu_poll_period_us = 1000000;
118 
119 module_param_named(pmu_pmu_poll_period_us, mmdc_pmu_poll_period_us, uint,
120 		S_IRUGO | S_IWUSR);
121 
122 static ktime_t mmdc_pmu_timer_period(void)
123 {
124 	return ns_to_ktime((u64)mmdc_pmu_poll_period_us * 1000);
125 }
126 
127 static ssize_t mmdc_pmu_cpumask_show(struct device *dev,
128 		struct device_attribute *attr, char *buf)
129 {
130 	struct mmdc_pmu *pmu_mmdc = dev_get_drvdata(dev);
131 
132 	return cpumap_print_to_pagebuf(true, buf, &pmu_mmdc->cpu);
133 }
134 
135 static struct device_attribute mmdc_pmu_cpumask_attr =
136 	__ATTR(cpumask, S_IRUGO, mmdc_pmu_cpumask_show, NULL);
137 
138 static struct attribute *mmdc_pmu_cpumask_attrs[] = {
139 	&mmdc_pmu_cpumask_attr.attr,
140 	NULL,
141 };
142 
143 static struct attribute_group mmdc_pmu_cpumask_attr_group = {
144 	.attrs = mmdc_pmu_cpumask_attrs,
145 };
146 
147 static struct attribute *mmdc_pmu_events_attrs[] = {
148 	&mmdc_pmu_total_cycles.attr.attr,
149 	&mmdc_pmu_busy_cycles.attr.attr,
150 	&mmdc_pmu_read_accesses.attr.attr,
151 	&mmdc_pmu_write_accesses.attr.attr,
152 	&mmdc_pmu_read_bytes.attr.attr,
153 	&mmdc_pmu_read_bytes_unit.attr.attr,
154 	&mmdc_pmu_read_bytes_scale.attr.attr,
155 	&mmdc_pmu_write_bytes.attr.attr,
156 	&mmdc_pmu_write_bytes_unit.attr.attr,
157 	&mmdc_pmu_write_bytes_scale.attr.attr,
158 	NULL,
159 };
160 
161 static struct attribute_group mmdc_pmu_events_attr_group = {
162 	.name = "events",
163 	.attrs = mmdc_pmu_events_attrs,
164 };
165 
166 PMU_FORMAT_ATTR(event, "config:0-63");
167 PMU_FORMAT_ATTR(axi_id, "config1:0-63");
168 
169 static struct attribute *mmdc_pmu_format_attrs[] = {
170 	&format_attr_event.attr,
171 	&format_attr_axi_id.attr,
172 	NULL,
173 };
174 
175 static struct attribute_group mmdc_pmu_format_attr_group = {
176 	.name = "format",
177 	.attrs = mmdc_pmu_format_attrs,
178 };
179 
180 static const struct attribute_group *attr_groups[] = {
181 	&mmdc_pmu_events_attr_group,
182 	&mmdc_pmu_format_attr_group,
183 	&mmdc_pmu_cpumask_attr_group,
184 	NULL,
185 };
186 
187 static u32 mmdc_pmu_read_counter(struct mmdc_pmu *pmu_mmdc, int cfg)
188 {
189 	void __iomem *mmdc_base, *reg;
190 
191 	mmdc_base = pmu_mmdc->mmdc_base;
192 
193 	switch (cfg) {
194 	case TOTAL_CYCLES:
195 		reg = mmdc_base + MMDC_MADPSR0;
196 		break;
197 	case BUSY_CYCLES:
198 		reg = mmdc_base + MMDC_MADPSR1;
199 		break;
200 	case READ_ACCESSES:
201 		reg = mmdc_base + MMDC_MADPSR2;
202 		break;
203 	case WRITE_ACCESSES:
204 		reg = mmdc_base + MMDC_MADPSR3;
205 		break;
206 	case READ_BYTES:
207 		reg = mmdc_base + MMDC_MADPSR4;
208 		break;
209 	case WRITE_BYTES:
210 		reg = mmdc_base + MMDC_MADPSR5;
211 		break;
212 	default:
213 		return WARN_ONCE(1,
214 			"invalid configuration %d for mmdc counter", cfg);
215 	}
216 	return readl(reg);
217 }
218 
219 static int mmdc_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
220 {
221 	struct mmdc_pmu *pmu_mmdc = hlist_entry_safe(node, struct mmdc_pmu, node);
222 	int target;
223 
224 	if (!cpumask_test_and_clear_cpu(cpu, &pmu_mmdc->cpu))
225 		return 0;
226 
227 	target = cpumask_any_but(cpu_online_mask, cpu);
228 	if (target >= nr_cpu_ids)
229 		return 0;
230 
231 	perf_pmu_migrate_context(&pmu_mmdc->pmu, cpu, target);
232 	cpumask_set_cpu(target, &pmu_mmdc->cpu);
233 
234 	return 0;
235 }
236 
237 static bool mmdc_pmu_group_event_is_valid(struct perf_event *event,
238 					  struct pmu *pmu,
239 					  unsigned long *used_counters)
240 {
241 	int cfg = event->attr.config;
242 
243 	if (is_software_event(event))
244 		return true;
245 
246 	if (event->pmu != pmu)
247 		return false;
248 
249 	return !test_and_set_bit(cfg, used_counters);
250 }
251 
252 /*
253  * Each event has a single fixed-purpose counter, so we can only have a
254  * single active event for each at any point in time. Here we just check
255  * for duplicates, and rely on mmdc_pmu_event_init to verify that the HW
256  * event numbers are valid.
257  */
258 static bool mmdc_pmu_group_is_valid(struct perf_event *event)
259 {
260 	struct pmu *pmu = event->pmu;
261 	struct perf_event *leader = event->group_leader;
262 	struct perf_event *sibling;
263 	unsigned long counter_mask = 0;
264 
265 	set_bit(leader->attr.config, &counter_mask);
266 
267 	if (event != leader) {
268 		if (!mmdc_pmu_group_event_is_valid(event, pmu, &counter_mask))
269 			return false;
270 	}
271 
272 	for_each_sibling_event(sibling, leader) {
273 		if (!mmdc_pmu_group_event_is_valid(sibling, pmu, &counter_mask))
274 			return false;
275 	}
276 
277 	return true;
278 }
279 
280 static int mmdc_pmu_event_init(struct perf_event *event)
281 {
282 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
283 	int cfg = event->attr.config;
284 
285 	if (event->attr.type != event->pmu->type)
286 		return -ENOENT;
287 
288 	if (is_sampling_event(event) || event->attach_state & PERF_ATTACH_TASK)
289 		return -EOPNOTSUPP;
290 
291 	if (event->cpu < 0) {
292 		dev_warn(pmu_mmdc->dev, "Can't provide per-task data!\n");
293 		return -EOPNOTSUPP;
294 	}
295 
296 	if (event->attr.exclude_user		||
297 			event->attr.exclude_kernel	||
298 			event->attr.exclude_hv		||
299 			event->attr.exclude_idle	||
300 			event->attr.exclude_host	||
301 			event->attr.exclude_guest	||
302 			event->attr.sample_period)
303 		return -EINVAL;
304 
305 	if (cfg < 0 || cfg >= MMDC_NUM_COUNTERS)
306 		return -EINVAL;
307 
308 	if (!mmdc_pmu_group_is_valid(event))
309 		return -EINVAL;
310 
311 	event->cpu = cpumask_first(&pmu_mmdc->cpu);
312 	return 0;
313 }
314 
315 static void mmdc_pmu_event_update(struct perf_event *event)
316 {
317 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
318 	struct hw_perf_event *hwc = &event->hw;
319 	u64 delta, prev_raw_count, new_raw_count;
320 
321 	do {
322 		prev_raw_count = local64_read(&hwc->prev_count);
323 		new_raw_count = mmdc_pmu_read_counter(pmu_mmdc,
324 						      event->attr.config);
325 	} while (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
326 		new_raw_count) != prev_raw_count);
327 
328 	delta = (new_raw_count - prev_raw_count) & 0xFFFFFFFF;
329 
330 	local64_add(delta, &event->count);
331 }
332 
333 static void mmdc_pmu_event_start(struct perf_event *event, int flags)
334 {
335 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
336 	struct hw_perf_event *hwc = &event->hw;
337 	void __iomem *mmdc_base, *reg;
338 	u32 val;
339 
340 	mmdc_base = pmu_mmdc->mmdc_base;
341 	reg = mmdc_base + MMDC_MADPCR0;
342 
343 	/*
344 	 * hrtimer is required because mmdc does not provide an interrupt so
345 	 * polling is necessary
346 	 */
347 	hrtimer_start(&pmu_mmdc->hrtimer, mmdc_pmu_timer_period(),
348 			HRTIMER_MODE_REL_PINNED);
349 
350 	local64_set(&hwc->prev_count, 0);
351 
352 	writel(DBG_RST, reg);
353 
354 	/*
355 	 * Write the AXI id parameter to MADPCR1.
356 	 */
357 	val = event->attr.config1;
358 	reg = mmdc_base + MMDC_MADPCR1;
359 	writel(val, reg);
360 
361 	reg = mmdc_base + MMDC_MADPCR0;
362 	val = DBG_EN;
363 	if (pmu_mmdc->devtype_data->flags & MMDC_FLAG_PROFILE_SEL)
364 		val |= PROFILE_SEL;
365 
366 	writel(val, reg);
367 }
368 
369 static int mmdc_pmu_event_add(struct perf_event *event, int flags)
370 {
371 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
372 	struct hw_perf_event *hwc = &event->hw;
373 
374 	int cfg = event->attr.config;
375 
376 	if (flags & PERF_EF_START)
377 		mmdc_pmu_event_start(event, flags);
378 
379 	if (pmu_mmdc->mmdc_events[cfg] != NULL)
380 		return -EAGAIN;
381 
382 	pmu_mmdc->mmdc_events[cfg] = event;
383 	pmu_mmdc->active_events++;
384 
385 	local64_set(&hwc->prev_count, mmdc_pmu_read_counter(pmu_mmdc, cfg));
386 
387 	return 0;
388 }
389 
390 static void mmdc_pmu_event_stop(struct perf_event *event, int flags)
391 {
392 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
393 	void __iomem *mmdc_base, *reg;
394 
395 	mmdc_base = pmu_mmdc->mmdc_base;
396 	reg = mmdc_base + MMDC_MADPCR0;
397 
398 	writel(PRF_FRZ, reg);
399 
400 	reg = mmdc_base + MMDC_MADPCR1;
401 	writel(MMDC_PRF_AXI_ID_CLEAR, reg);
402 
403 	mmdc_pmu_event_update(event);
404 }
405 
406 static void mmdc_pmu_event_del(struct perf_event *event, int flags)
407 {
408 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
409 	int cfg = event->attr.config;
410 
411 	pmu_mmdc->mmdc_events[cfg] = NULL;
412 	pmu_mmdc->active_events--;
413 
414 	if (pmu_mmdc->active_events == 0)
415 		hrtimer_cancel(&pmu_mmdc->hrtimer);
416 
417 	mmdc_pmu_event_stop(event, PERF_EF_UPDATE);
418 }
419 
420 static void mmdc_pmu_overflow_handler(struct mmdc_pmu *pmu_mmdc)
421 {
422 	int i;
423 
424 	for (i = 0; i < MMDC_NUM_COUNTERS; i++) {
425 		struct perf_event *event = pmu_mmdc->mmdc_events[i];
426 
427 		if (event)
428 			mmdc_pmu_event_update(event);
429 	}
430 }
431 
432 static enum hrtimer_restart mmdc_pmu_timer_handler(struct hrtimer *hrtimer)
433 {
434 	struct mmdc_pmu *pmu_mmdc = container_of(hrtimer, struct mmdc_pmu,
435 			hrtimer);
436 
437 	mmdc_pmu_overflow_handler(pmu_mmdc);
438 	hrtimer_forward_now(hrtimer, mmdc_pmu_timer_period());
439 
440 	return HRTIMER_RESTART;
441 }
442 
443 static int mmdc_pmu_init(struct mmdc_pmu *pmu_mmdc,
444 		void __iomem *mmdc_base, struct device *dev)
445 {
446 	int mmdc_num;
447 
448 	*pmu_mmdc = (struct mmdc_pmu) {
449 		.pmu = (struct pmu) {
450 			.task_ctx_nr    = perf_invalid_context,
451 			.attr_groups    = attr_groups,
452 			.event_init     = mmdc_pmu_event_init,
453 			.add            = mmdc_pmu_event_add,
454 			.del            = mmdc_pmu_event_del,
455 			.start          = mmdc_pmu_event_start,
456 			.stop           = mmdc_pmu_event_stop,
457 			.read           = mmdc_pmu_event_update,
458 		},
459 		.mmdc_base = mmdc_base,
460 		.dev = dev,
461 		.active_events = 0,
462 	};
463 
464 	mmdc_num = ida_simple_get(&mmdc_ida, 0, 0, GFP_KERNEL);
465 
466 	return mmdc_num;
467 }
468 
469 static int imx_mmdc_remove(struct platform_device *pdev)
470 {
471 	struct mmdc_pmu *pmu_mmdc = platform_get_drvdata(pdev);
472 
473 	cpuhp_state_remove_instance_nocalls(cpuhp_mmdc_state, &pmu_mmdc->node);
474 	perf_pmu_unregister(&pmu_mmdc->pmu);
475 	kfree(pmu_mmdc);
476 	return 0;
477 }
478 
479 static int imx_mmdc_perf_init(struct platform_device *pdev, void __iomem *mmdc_base)
480 {
481 	struct mmdc_pmu *pmu_mmdc;
482 	char *name;
483 	int mmdc_num;
484 	int ret;
485 	const struct of_device_id *of_id =
486 		of_match_device(imx_mmdc_dt_ids, &pdev->dev);
487 
488 	pmu_mmdc = kzalloc(sizeof(*pmu_mmdc), GFP_KERNEL);
489 	if (!pmu_mmdc) {
490 		pr_err("failed to allocate PMU device!\n");
491 		return -ENOMEM;
492 	}
493 
494 	/* The first instance registers the hotplug state */
495 	if (!cpuhp_mmdc_state) {
496 		ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN,
497 					      "perf/arm/mmdc:online", NULL,
498 					      mmdc_pmu_offline_cpu);
499 		if (ret < 0) {
500 			pr_err("cpuhp_setup_state_multi failed\n");
501 			goto pmu_free;
502 		}
503 		cpuhp_mmdc_state = ret;
504 	}
505 
506 	mmdc_num = mmdc_pmu_init(pmu_mmdc, mmdc_base, &pdev->dev);
507 	if (mmdc_num == 0)
508 		name = "mmdc";
509 	else
510 		name = devm_kasprintf(&pdev->dev,
511 				GFP_KERNEL, "mmdc%d", mmdc_num);
512 
513 	pmu_mmdc->devtype_data = (struct fsl_mmdc_devtype_data *)of_id->data;
514 
515 	hrtimer_init(&pmu_mmdc->hrtimer, CLOCK_MONOTONIC,
516 			HRTIMER_MODE_REL);
517 	pmu_mmdc->hrtimer.function = mmdc_pmu_timer_handler;
518 
519 	cpumask_set_cpu(raw_smp_processor_id(), &pmu_mmdc->cpu);
520 
521 	/* Register the pmu instance for cpu hotplug */
522 	cpuhp_state_add_instance_nocalls(cpuhp_mmdc_state, &pmu_mmdc->node);
523 
524 	ret = perf_pmu_register(&(pmu_mmdc->pmu), name, -1);
525 	if (ret)
526 		goto pmu_register_err;
527 
528 	platform_set_drvdata(pdev, pmu_mmdc);
529 	return 0;
530 
531 pmu_register_err:
532 	pr_warn("MMDC Perf PMU failed (%d), disabled\n", ret);
533 	cpuhp_state_remove_instance_nocalls(cpuhp_mmdc_state, &pmu_mmdc->node);
534 	hrtimer_cancel(&pmu_mmdc->hrtimer);
535 pmu_free:
536 	kfree(pmu_mmdc);
537 	return ret;
538 }
539 
540 #else
541 #define imx_mmdc_remove NULL
542 #define imx_mmdc_perf_init(pdev, mmdc_base) 0
543 #endif
544 
545 static int imx_mmdc_probe(struct platform_device *pdev)
546 {
547 	struct device_node *np = pdev->dev.of_node;
548 	void __iomem *mmdc_base, *reg;
549 	u32 val;
550 
551 	mmdc_base = of_iomap(np, 0);
552 	WARN_ON(!mmdc_base);
553 
554 	reg = mmdc_base + MMDC_MDMISC;
555 	/* Get ddr type */
556 	val = readl_relaxed(reg);
557 	ddr_type = (val & BM_MMDC_MDMISC_DDR_TYPE) >>
558 		 BP_MMDC_MDMISC_DDR_TYPE;
559 
560 	reg = mmdc_base + MMDC_MAPSR;
561 
562 	/* Enable automatic power saving */
563 	val = readl_relaxed(reg);
564 	val &= ~(1 << BP_MMDC_MAPSR_PSD);
565 	writel_relaxed(val, reg);
566 
567 	return imx_mmdc_perf_init(pdev, mmdc_base);
568 }
569 
570 int imx_mmdc_get_ddr_type(void)
571 {
572 	return ddr_type;
573 }
574 
575 static struct platform_driver imx_mmdc_driver = {
576 	.driver		= {
577 		.name	= "imx-mmdc",
578 		.of_match_table = imx_mmdc_dt_ids,
579 	},
580 	.probe		= imx_mmdc_probe,
581 	.remove		= imx_mmdc_remove,
582 };
583 
584 static int __init imx_mmdc_init(void)
585 {
586 	return platform_driver_register(&imx_mmdc_driver);
587 }
588 postcore_initcall(imx_mmdc_init);
589