xref: /openbmc/linux/arch/arm/mach-imx/mmdc.c (revision 8730046c)
1 /*
2  * Copyright 2011,2016 Freescale Semiconductor, Inc.
3  * Copyright 2011 Linaro Ltd.
4  *
5  * The code contained herein is licensed under the GNU General Public
6  * License. You may obtain a copy of the GNU General Public License
7  * Version 2 or later at the following locations:
8  *
9  * http://www.opensource.org/licenses/gpl-license.html
10  * http://www.gnu.org/copyleft/gpl.html
11  */
12 
13 #include <linux/hrtimer.h>
14 #include <linux/init.h>
15 #include <linux/interrupt.h>
16 #include <linux/io.h>
17 #include <linux/module.h>
18 #include <linux/of.h>
19 #include <linux/of_address.h>
20 #include <linux/of_device.h>
21 #include <linux/perf_event.h>
22 #include <linux/slab.h>
23 
24 #include "common.h"
25 
26 #define MMDC_MAPSR		0x404
27 #define BP_MMDC_MAPSR_PSD	0
28 #define BP_MMDC_MAPSR_PSS	4
29 
30 #define MMDC_MDMISC		0x18
31 #define BM_MMDC_MDMISC_DDR_TYPE	0x18
32 #define BP_MMDC_MDMISC_DDR_TYPE	0x3
33 
34 #define TOTAL_CYCLES		0x0
35 #define BUSY_CYCLES		0x1
36 #define READ_ACCESSES		0x2
37 #define WRITE_ACCESSES		0x3
38 #define READ_BYTES		0x4
39 #define WRITE_BYTES		0x5
40 
41 /* Enables, resets, freezes, overflow profiling*/
42 #define DBG_DIS			0x0
43 #define DBG_EN			0x1
44 #define DBG_RST			0x2
45 #define PRF_FRZ			0x4
46 #define CYC_OVF			0x8
47 #define PROFILE_SEL		0x10
48 
49 #define MMDC_MADPCR0	0x410
50 #define MMDC_MADPSR0	0x418
51 #define MMDC_MADPSR1	0x41C
52 #define MMDC_MADPSR2	0x420
53 #define MMDC_MADPSR3	0x424
54 #define MMDC_MADPSR4	0x428
55 #define MMDC_MADPSR5	0x42C
56 
57 #define MMDC_NUM_COUNTERS	6
58 
59 #define MMDC_FLAG_PROFILE_SEL	0x1
60 
61 #define to_mmdc_pmu(p) container_of(p, struct mmdc_pmu, pmu)
62 
63 static enum cpuhp_state cpuhp_mmdc_state;
64 static int ddr_type;
65 
66 struct fsl_mmdc_devtype_data {
67 	unsigned int flags;
68 };
69 
70 static const struct fsl_mmdc_devtype_data imx6q_data = {
71 };
72 
73 static const struct fsl_mmdc_devtype_data imx6qp_data = {
74 	.flags = MMDC_FLAG_PROFILE_SEL,
75 };
76 
77 static const struct of_device_id imx_mmdc_dt_ids[] = {
78 	{ .compatible = "fsl,imx6q-mmdc", .data = (void *)&imx6q_data},
79 	{ .compatible = "fsl,imx6qp-mmdc", .data = (void *)&imx6qp_data},
80 	{ /* sentinel */ }
81 };
82 
83 #ifdef CONFIG_PERF_EVENTS
84 
85 static DEFINE_IDA(mmdc_ida);
86 
87 PMU_EVENT_ATTR_STRING(total-cycles, mmdc_pmu_total_cycles, "event=0x00")
88 PMU_EVENT_ATTR_STRING(busy-cycles, mmdc_pmu_busy_cycles, "event=0x01")
89 PMU_EVENT_ATTR_STRING(read-accesses, mmdc_pmu_read_accesses, "event=0x02")
90 PMU_EVENT_ATTR_STRING(write-accesses, mmdc_pmu_write_accesses, "config=0x03")
91 PMU_EVENT_ATTR_STRING(read-bytes, mmdc_pmu_read_bytes, "event=0x04")
92 PMU_EVENT_ATTR_STRING(read-bytes.unit, mmdc_pmu_read_bytes_unit, "MB");
93 PMU_EVENT_ATTR_STRING(read-bytes.scale, mmdc_pmu_read_bytes_scale, "0.000001");
94 PMU_EVENT_ATTR_STRING(write-bytes, mmdc_pmu_write_bytes, "event=0x05")
95 PMU_EVENT_ATTR_STRING(write-bytes.unit, mmdc_pmu_write_bytes_unit, "MB");
96 PMU_EVENT_ATTR_STRING(write-bytes.scale, mmdc_pmu_write_bytes_scale, "0.000001");
97 
98 struct mmdc_pmu {
99 	struct pmu pmu;
100 	void __iomem *mmdc_base;
101 	cpumask_t cpu;
102 	struct hrtimer hrtimer;
103 	unsigned int active_events;
104 	struct device *dev;
105 	struct perf_event *mmdc_events[MMDC_NUM_COUNTERS];
106 	struct hlist_node node;
107 	struct fsl_mmdc_devtype_data *devtype_data;
108 };
109 
110 /*
111  * Polling period is set to one second, overflow of total-cycles (the fastest
112  * increasing counter) takes ten seconds so one second is safe
113  */
114 static unsigned int mmdc_pmu_poll_period_us = 1000000;
115 
116 module_param_named(pmu_pmu_poll_period_us, mmdc_pmu_poll_period_us, uint,
117 		S_IRUGO | S_IWUSR);
118 
119 static ktime_t mmdc_pmu_timer_period(void)
120 {
121 	return ns_to_ktime((u64)mmdc_pmu_poll_period_us * 1000);
122 }
123 
124 static ssize_t mmdc_pmu_cpumask_show(struct device *dev,
125 		struct device_attribute *attr, char *buf)
126 {
127 	struct mmdc_pmu *pmu_mmdc = dev_get_drvdata(dev);
128 
129 	return cpumap_print_to_pagebuf(true, buf, &pmu_mmdc->cpu);
130 }
131 
132 static struct device_attribute mmdc_pmu_cpumask_attr =
133 	__ATTR(cpumask, S_IRUGO, mmdc_pmu_cpumask_show, NULL);
134 
135 static struct attribute *mmdc_pmu_cpumask_attrs[] = {
136 	&mmdc_pmu_cpumask_attr.attr,
137 	NULL,
138 };
139 
140 static struct attribute_group mmdc_pmu_cpumask_attr_group = {
141 	.attrs = mmdc_pmu_cpumask_attrs,
142 };
143 
144 static struct attribute *mmdc_pmu_events_attrs[] = {
145 	&mmdc_pmu_total_cycles.attr.attr,
146 	&mmdc_pmu_busy_cycles.attr.attr,
147 	&mmdc_pmu_read_accesses.attr.attr,
148 	&mmdc_pmu_write_accesses.attr.attr,
149 	&mmdc_pmu_read_bytes.attr.attr,
150 	&mmdc_pmu_read_bytes_unit.attr.attr,
151 	&mmdc_pmu_read_bytes_scale.attr.attr,
152 	&mmdc_pmu_write_bytes.attr.attr,
153 	&mmdc_pmu_write_bytes_unit.attr.attr,
154 	&mmdc_pmu_write_bytes_scale.attr.attr,
155 	NULL,
156 };
157 
158 static struct attribute_group mmdc_pmu_events_attr_group = {
159 	.name = "events",
160 	.attrs = mmdc_pmu_events_attrs,
161 };
162 
163 PMU_FORMAT_ATTR(event, "config:0-63");
164 static struct attribute *mmdc_pmu_format_attrs[] = {
165 	&format_attr_event.attr,
166 	NULL,
167 };
168 
169 static struct attribute_group mmdc_pmu_format_attr_group = {
170 	.name = "format",
171 	.attrs = mmdc_pmu_format_attrs,
172 };
173 
174 static const struct attribute_group *attr_groups[] = {
175 	&mmdc_pmu_events_attr_group,
176 	&mmdc_pmu_format_attr_group,
177 	&mmdc_pmu_cpumask_attr_group,
178 	NULL,
179 };
180 
181 static u32 mmdc_pmu_read_counter(struct mmdc_pmu *pmu_mmdc, int cfg)
182 {
183 	void __iomem *mmdc_base, *reg;
184 
185 	mmdc_base = pmu_mmdc->mmdc_base;
186 
187 	switch (cfg) {
188 	case TOTAL_CYCLES:
189 		reg = mmdc_base + MMDC_MADPSR0;
190 		break;
191 	case BUSY_CYCLES:
192 		reg = mmdc_base + MMDC_MADPSR1;
193 		break;
194 	case READ_ACCESSES:
195 		reg = mmdc_base + MMDC_MADPSR2;
196 		break;
197 	case WRITE_ACCESSES:
198 		reg = mmdc_base + MMDC_MADPSR3;
199 		break;
200 	case READ_BYTES:
201 		reg = mmdc_base + MMDC_MADPSR4;
202 		break;
203 	case WRITE_BYTES:
204 		reg = mmdc_base + MMDC_MADPSR5;
205 		break;
206 	default:
207 		return WARN_ONCE(1,
208 			"invalid configuration %d for mmdc counter", cfg);
209 	}
210 	return readl(reg);
211 }
212 
213 static int mmdc_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
214 {
215 	struct mmdc_pmu *pmu_mmdc = hlist_entry_safe(node, struct mmdc_pmu, node);
216 	int target;
217 
218 	if (!cpumask_test_and_clear_cpu(cpu, &pmu_mmdc->cpu))
219 		return 0;
220 
221 	target = cpumask_any_but(cpu_online_mask, cpu);
222 	if (target >= nr_cpu_ids)
223 		return 0;
224 
225 	perf_pmu_migrate_context(&pmu_mmdc->pmu, cpu, target);
226 	cpumask_set_cpu(target, &pmu_mmdc->cpu);
227 
228 	return 0;
229 }
230 
231 static bool mmdc_pmu_group_event_is_valid(struct perf_event *event,
232 					  struct pmu *pmu,
233 					  unsigned long *used_counters)
234 {
235 	int cfg = event->attr.config;
236 
237 	if (is_software_event(event))
238 		return true;
239 
240 	if (event->pmu != pmu)
241 		return false;
242 
243 	return !test_and_set_bit(cfg, used_counters);
244 }
245 
246 /*
247  * Each event has a single fixed-purpose counter, so we can only have a
248  * single active event for each at any point in time. Here we just check
249  * for duplicates, and rely on mmdc_pmu_event_init to verify that the HW
250  * event numbers are valid.
251  */
252 static bool mmdc_pmu_group_is_valid(struct perf_event *event)
253 {
254 	struct pmu *pmu = event->pmu;
255 	struct perf_event *leader = event->group_leader;
256 	struct perf_event *sibling;
257 	unsigned long counter_mask = 0;
258 
259 	set_bit(leader->attr.config, &counter_mask);
260 
261 	if (event != leader) {
262 		if (!mmdc_pmu_group_event_is_valid(event, pmu, &counter_mask))
263 			return false;
264 	}
265 
266 	list_for_each_entry(sibling, &leader->sibling_list, group_entry) {
267 		if (!mmdc_pmu_group_event_is_valid(sibling, pmu, &counter_mask))
268 			return false;
269 	}
270 
271 	return true;
272 }
273 
274 static int mmdc_pmu_event_init(struct perf_event *event)
275 {
276 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
277 	int cfg = event->attr.config;
278 
279 	if (event->attr.type != event->pmu->type)
280 		return -ENOENT;
281 
282 	if (is_sampling_event(event) || event->attach_state & PERF_ATTACH_TASK)
283 		return -EOPNOTSUPP;
284 
285 	if (event->cpu < 0) {
286 		dev_warn(pmu_mmdc->dev, "Can't provide per-task data!\n");
287 		return -EOPNOTSUPP;
288 	}
289 
290 	if (event->attr.exclude_user		||
291 			event->attr.exclude_kernel	||
292 			event->attr.exclude_hv		||
293 			event->attr.exclude_idle	||
294 			event->attr.exclude_host	||
295 			event->attr.exclude_guest	||
296 			event->attr.sample_period)
297 		return -EINVAL;
298 
299 	if (cfg < 0 || cfg >= MMDC_NUM_COUNTERS)
300 		return -EINVAL;
301 
302 	if (!mmdc_pmu_group_is_valid(event))
303 		return -EINVAL;
304 
305 	event->cpu = cpumask_first(&pmu_mmdc->cpu);
306 	return 0;
307 }
308 
309 static void mmdc_pmu_event_update(struct perf_event *event)
310 {
311 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
312 	struct hw_perf_event *hwc = &event->hw;
313 	u64 delta, prev_raw_count, new_raw_count;
314 
315 	do {
316 		prev_raw_count = local64_read(&hwc->prev_count);
317 		new_raw_count = mmdc_pmu_read_counter(pmu_mmdc,
318 						      event->attr.config);
319 	} while (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
320 		new_raw_count) != prev_raw_count);
321 
322 	delta = (new_raw_count - prev_raw_count) & 0xFFFFFFFF;
323 
324 	local64_add(delta, &event->count);
325 }
326 
327 static void mmdc_pmu_event_start(struct perf_event *event, int flags)
328 {
329 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
330 	struct hw_perf_event *hwc = &event->hw;
331 	void __iomem *mmdc_base, *reg;
332 	u32 val;
333 
334 	mmdc_base = pmu_mmdc->mmdc_base;
335 	reg = mmdc_base + MMDC_MADPCR0;
336 
337 	/*
338 	 * hrtimer is required because mmdc does not provide an interrupt so
339 	 * polling is necessary
340 	 */
341 	hrtimer_start(&pmu_mmdc->hrtimer, mmdc_pmu_timer_period(),
342 			HRTIMER_MODE_REL_PINNED);
343 
344 	local64_set(&hwc->prev_count, 0);
345 
346 	writel(DBG_RST, reg);
347 
348 	val = DBG_EN;
349 	if (pmu_mmdc->devtype_data->flags & MMDC_FLAG_PROFILE_SEL)
350 		val |= PROFILE_SEL;
351 
352 	writel(val, reg);
353 }
354 
355 static int mmdc_pmu_event_add(struct perf_event *event, int flags)
356 {
357 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
358 	struct hw_perf_event *hwc = &event->hw;
359 
360 	int cfg = event->attr.config;
361 
362 	if (flags & PERF_EF_START)
363 		mmdc_pmu_event_start(event, flags);
364 
365 	if (pmu_mmdc->mmdc_events[cfg] != NULL)
366 		return -EAGAIN;
367 
368 	pmu_mmdc->mmdc_events[cfg] = event;
369 	pmu_mmdc->active_events++;
370 
371 	local64_set(&hwc->prev_count, mmdc_pmu_read_counter(pmu_mmdc, cfg));
372 
373 	return 0;
374 }
375 
376 static void mmdc_pmu_event_stop(struct perf_event *event, int flags)
377 {
378 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
379 	void __iomem *mmdc_base, *reg;
380 
381 	mmdc_base = pmu_mmdc->mmdc_base;
382 	reg = mmdc_base + MMDC_MADPCR0;
383 
384 	writel(PRF_FRZ, reg);
385 	mmdc_pmu_event_update(event);
386 }
387 
388 static void mmdc_pmu_event_del(struct perf_event *event, int flags)
389 {
390 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
391 	int cfg = event->attr.config;
392 
393 	pmu_mmdc->mmdc_events[cfg] = NULL;
394 	pmu_mmdc->active_events--;
395 
396 	if (pmu_mmdc->active_events == 0)
397 		hrtimer_cancel(&pmu_mmdc->hrtimer);
398 
399 	mmdc_pmu_event_stop(event, PERF_EF_UPDATE);
400 }
401 
402 static void mmdc_pmu_overflow_handler(struct mmdc_pmu *pmu_mmdc)
403 {
404 	int i;
405 
406 	for (i = 0; i < MMDC_NUM_COUNTERS; i++) {
407 		struct perf_event *event = pmu_mmdc->mmdc_events[i];
408 
409 		if (event)
410 			mmdc_pmu_event_update(event);
411 	}
412 }
413 
414 static enum hrtimer_restart mmdc_pmu_timer_handler(struct hrtimer *hrtimer)
415 {
416 	struct mmdc_pmu *pmu_mmdc = container_of(hrtimer, struct mmdc_pmu,
417 			hrtimer);
418 
419 	mmdc_pmu_overflow_handler(pmu_mmdc);
420 	hrtimer_forward_now(hrtimer, mmdc_pmu_timer_period());
421 
422 	return HRTIMER_RESTART;
423 }
424 
425 static int mmdc_pmu_init(struct mmdc_pmu *pmu_mmdc,
426 		void __iomem *mmdc_base, struct device *dev)
427 {
428 	int mmdc_num;
429 
430 	*pmu_mmdc = (struct mmdc_pmu) {
431 		.pmu = (struct pmu) {
432 			.task_ctx_nr    = perf_invalid_context,
433 			.attr_groups    = attr_groups,
434 			.event_init     = mmdc_pmu_event_init,
435 			.add            = mmdc_pmu_event_add,
436 			.del            = mmdc_pmu_event_del,
437 			.start          = mmdc_pmu_event_start,
438 			.stop           = mmdc_pmu_event_stop,
439 			.read           = mmdc_pmu_event_update,
440 		},
441 		.mmdc_base = mmdc_base,
442 		.dev = dev,
443 		.active_events = 0,
444 	};
445 
446 	mmdc_num = ida_simple_get(&mmdc_ida, 0, 0, GFP_KERNEL);
447 
448 	return mmdc_num;
449 }
450 
451 static int imx_mmdc_remove(struct platform_device *pdev)
452 {
453 	struct mmdc_pmu *pmu_mmdc = platform_get_drvdata(pdev);
454 
455 	cpuhp_state_remove_instance_nocalls(cpuhp_mmdc_state, &pmu_mmdc->node);
456 	perf_pmu_unregister(&pmu_mmdc->pmu);
457 	kfree(pmu_mmdc);
458 	return 0;
459 }
460 
461 static int imx_mmdc_perf_init(struct platform_device *pdev, void __iomem *mmdc_base)
462 {
463 	struct mmdc_pmu *pmu_mmdc;
464 	char *name;
465 	int mmdc_num;
466 	int ret;
467 	const struct of_device_id *of_id =
468 		of_match_device(imx_mmdc_dt_ids, &pdev->dev);
469 
470 	pmu_mmdc = kzalloc(sizeof(*pmu_mmdc), GFP_KERNEL);
471 	if (!pmu_mmdc) {
472 		pr_err("failed to allocate PMU device!\n");
473 		return -ENOMEM;
474 	}
475 
476 	/* The first instance registers the hotplug state */
477 	if (!cpuhp_mmdc_state) {
478 		ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN,
479 					      "perf/arm/mmdc:online", NULL,
480 					      mmdc_pmu_offline_cpu);
481 		if (ret < 0) {
482 			pr_err("cpuhp_setup_state_multi failed\n");
483 			goto pmu_free;
484 		}
485 		cpuhp_mmdc_state = ret;
486 	}
487 
488 	mmdc_num = mmdc_pmu_init(pmu_mmdc, mmdc_base, &pdev->dev);
489 	if (mmdc_num == 0)
490 		name = "mmdc";
491 	else
492 		name = devm_kasprintf(&pdev->dev,
493 				GFP_KERNEL, "mmdc%d", mmdc_num);
494 
495 	pmu_mmdc->devtype_data = (struct fsl_mmdc_devtype_data *)of_id->data;
496 
497 	hrtimer_init(&pmu_mmdc->hrtimer, CLOCK_MONOTONIC,
498 			HRTIMER_MODE_REL);
499 	pmu_mmdc->hrtimer.function = mmdc_pmu_timer_handler;
500 
501 	cpumask_set_cpu(raw_smp_processor_id(), &pmu_mmdc->cpu);
502 
503 	/* Register the pmu instance for cpu hotplug */
504 	cpuhp_state_add_instance_nocalls(cpuhp_mmdc_state, &pmu_mmdc->node);
505 
506 	ret = perf_pmu_register(&(pmu_mmdc->pmu), name, -1);
507 	if (ret)
508 		goto pmu_register_err;
509 
510 	platform_set_drvdata(pdev, pmu_mmdc);
511 	return 0;
512 
513 pmu_register_err:
514 	pr_warn("MMDC Perf PMU failed (%d), disabled\n", ret);
515 	cpuhp_state_remove_instance_nocalls(cpuhp_mmdc_state, &pmu_mmdc->node);
516 	hrtimer_cancel(&pmu_mmdc->hrtimer);
517 pmu_free:
518 	kfree(pmu_mmdc);
519 	return ret;
520 }
521 
522 #else
523 #define imx_mmdc_remove NULL
524 #define imx_mmdc_perf_init(pdev, mmdc_base) 0
525 #endif
526 
527 static int imx_mmdc_probe(struct platform_device *pdev)
528 {
529 	struct device_node *np = pdev->dev.of_node;
530 	void __iomem *mmdc_base, *reg;
531 	u32 val;
532 	int timeout = 0x400;
533 
534 	mmdc_base = of_iomap(np, 0);
535 	WARN_ON(!mmdc_base);
536 
537 	reg = mmdc_base + MMDC_MDMISC;
538 	/* Get ddr type */
539 	val = readl_relaxed(reg);
540 	ddr_type = (val & BM_MMDC_MDMISC_DDR_TYPE) >>
541 		 BP_MMDC_MDMISC_DDR_TYPE;
542 
543 	reg = mmdc_base + MMDC_MAPSR;
544 
545 	/* Enable automatic power saving */
546 	val = readl_relaxed(reg);
547 	val &= ~(1 << BP_MMDC_MAPSR_PSD);
548 	writel_relaxed(val, reg);
549 
550 	/* Ensure it's successfully enabled */
551 	while (!(readl_relaxed(reg) & 1 << BP_MMDC_MAPSR_PSS) && --timeout)
552 		cpu_relax();
553 
554 	if (unlikely(!timeout)) {
555 		pr_warn("%s: failed to enable automatic power saving\n",
556 			__func__);
557 		return -EBUSY;
558 	}
559 
560 	return imx_mmdc_perf_init(pdev, mmdc_base);
561 }
562 
563 int imx_mmdc_get_ddr_type(void)
564 {
565 	return ddr_type;
566 }
567 
568 static struct platform_driver imx_mmdc_driver = {
569 	.driver		= {
570 		.name	= "imx-mmdc",
571 		.of_match_table = imx_mmdc_dt_ids,
572 	},
573 	.probe		= imx_mmdc_probe,
574 	.remove		= imx_mmdc_remove,
575 };
576 
577 static int __init imx_mmdc_init(void)
578 {
579 	return platform_driver_register(&imx_mmdc_driver);
580 }
581 postcore_initcall(imx_mmdc_init);
582