xref: /linux/arch/arm/mach-imx/mmdc.c (revision 308d3165d8b2b98d3dc3d97d6662062735daea67)
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 int ddr_type;
64 
65 struct fsl_mmdc_devtype_data {
66 	unsigned int flags;
67 };
68 
69 static const struct fsl_mmdc_devtype_data imx6q_data = {
70 };
71 
72 static const struct fsl_mmdc_devtype_data imx6qp_data = {
73 	.flags = MMDC_FLAG_PROFILE_SEL,
74 };
75 
76 static const struct of_device_id imx_mmdc_dt_ids[] = {
77 	{ .compatible = "fsl,imx6q-mmdc", .data = (void *)&imx6q_data},
78 	{ .compatible = "fsl,imx6qp-mmdc", .data = (void *)&imx6qp_data},
79 	{ /* sentinel */ }
80 };
81 
82 #ifdef CONFIG_PERF_EVENTS
83 
84 static DEFINE_IDA(mmdc_ida);
85 
86 PMU_EVENT_ATTR_STRING(total-cycles, mmdc_pmu_total_cycles, "event=0x00")
87 PMU_EVENT_ATTR_STRING(busy-cycles, mmdc_pmu_busy_cycles, "event=0x01")
88 PMU_EVENT_ATTR_STRING(read-accesses, mmdc_pmu_read_accesses, "event=0x02")
89 PMU_EVENT_ATTR_STRING(write-accesses, mmdc_pmu_write_accesses, "config=0x03")
90 PMU_EVENT_ATTR_STRING(read-bytes, mmdc_pmu_read_bytes, "event=0x04")
91 PMU_EVENT_ATTR_STRING(read-bytes.unit, mmdc_pmu_read_bytes_unit, "MB");
92 PMU_EVENT_ATTR_STRING(read-bytes.scale, mmdc_pmu_read_bytes_scale, "0.000001");
93 PMU_EVENT_ATTR_STRING(write-bytes, mmdc_pmu_write_bytes, "event=0x05")
94 PMU_EVENT_ATTR_STRING(write-bytes.unit, mmdc_pmu_write_bytes_unit, "MB");
95 PMU_EVENT_ATTR_STRING(write-bytes.scale, mmdc_pmu_write_bytes_scale, "0.000001");
96 
97 struct mmdc_pmu {
98 	struct pmu pmu;
99 	void __iomem *mmdc_base;
100 	cpumask_t cpu;
101 	struct hrtimer hrtimer;
102 	unsigned int active_events;
103 	struct device *dev;
104 	struct perf_event *mmdc_events[MMDC_NUM_COUNTERS];
105 	struct hlist_node node;
106 	struct fsl_mmdc_devtype_data *devtype_data;
107 };
108 
109 /*
110  * Polling period is set to one second, overflow of total-cycles (the fastest
111  * increasing counter) takes ten seconds so one second is safe
112  */
113 static unsigned int mmdc_pmu_poll_period_us = 1000000;
114 
115 module_param_named(pmu_pmu_poll_period_us, mmdc_pmu_poll_period_us, uint,
116 		S_IRUGO | S_IWUSR);
117 
118 static ktime_t mmdc_pmu_timer_period(void)
119 {
120 	return ns_to_ktime((u64)mmdc_pmu_poll_period_us * 1000);
121 }
122 
123 static ssize_t mmdc_pmu_cpumask_show(struct device *dev,
124 		struct device_attribute *attr, char *buf)
125 {
126 	struct mmdc_pmu *pmu_mmdc = dev_get_drvdata(dev);
127 
128 	return cpumap_print_to_pagebuf(true, buf, &pmu_mmdc->cpu);
129 }
130 
131 static struct device_attribute mmdc_pmu_cpumask_attr =
132 	__ATTR(cpumask, S_IRUGO, mmdc_pmu_cpumask_show, NULL);
133 
134 static struct attribute *mmdc_pmu_cpumask_attrs[] = {
135 	&mmdc_pmu_cpumask_attr.attr,
136 	NULL,
137 };
138 
139 static struct attribute_group mmdc_pmu_cpumask_attr_group = {
140 	.attrs = mmdc_pmu_cpumask_attrs,
141 };
142 
143 static struct attribute *mmdc_pmu_events_attrs[] = {
144 	&mmdc_pmu_total_cycles.attr.attr,
145 	&mmdc_pmu_busy_cycles.attr.attr,
146 	&mmdc_pmu_read_accesses.attr.attr,
147 	&mmdc_pmu_write_accesses.attr.attr,
148 	&mmdc_pmu_read_bytes.attr.attr,
149 	&mmdc_pmu_read_bytes_unit.attr.attr,
150 	&mmdc_pmu_read_bytes_scale.attr.attr,
151 	&mmdc_pmu_write_bytes.attr.attr,
152 	&mmdc_pmu_write_bytes_unit.attr.attr,
153 	&mmdc_pmu_write_bytes_scale.attr.attr,
154 	NULL,
155 };
156 
157 static struct attribute_group mmdc_pmu_events_attr_group = {
158 	.name = "events",
159 	.attrs = mmdc_pmu_events_attrs,
160 };
161 
162 PMU_FORMAT_ATTR(event, "config:0-63");
163 static struct attribute *mmdc_pmu_format_attrs[] = {
164 	&format_attr_event.attr,
165 	NULL,
166 };
167 
168 static struct attribute_group mmdc_pmu_format_attr_group = {
169 	.name = "format",
170 	.attrs = mmdc_pmu_format_attrs,
171 };
172 
173 static const struct attribute_group *attr_groups[] = {
174 	&mmdc_pmu_events_attr_group,
175 	&mmdc_pmu_format_attr_group,
176 	&mmdc_pmu_cpumask_attr_group,
177 	NULL,
178 };
179 
180 static u32 mmdc_pmu_read_counter(struct mmdc_pmu *pmu_mmdc, int cfg)
181 {
182 	void __iomem *mmdc_base, *reg;
183 
184 	mmdc_base = pmu_mmdc->mmdc_base;
185 
186 	switch (cfg) {
187 	case TOTAL_CYCLES:
188 		reg = mmdc_base + MMDC_MADPSR0;
189 		break;
190 	case BUSY_CYCLES:
191 		reg = mmdc_base + MMDC_MADPSR1;
192 		break;
193 	case READ_ACCESSES:
194 		reg = mmdc_base + MMDC_MADPSR2;
195 		break;
196 	case WRITE_ACCESSES:
197 		reg = mmdc_base + MMDC_MADPSR3;
198 		break;
199 	case READ_BYTES:
200 		reg = mmdc_base + MMDC_MADPSR4;
201 		break;
202 	case WRITE_BYTES:
203 		reg = mmdc_base + MMDC_MADPSR5;
204 		break;
205 	default:
206 		return WARN_ONCE(1,
207 			"invalid configuration %d for mmdc counter", cfg);
208 	}
209 	return readl(reg);
210 }
211 
212 static int mmdc_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
213 {
214 	struct mmdc_pmu *pmu_mmdc = hlist_entry_safe(node, struct mmdc_pmu, node);
215 	int target;
216 
217 	if (!cpumask_test_and_clear_cpu(cpu, &pmu_mmdc->cpu))
218 		return 0;
219 
220 	target = cpumask_any_but(cpu_online_mask, cpu);
221 	if (target >= nr_cpu_ids)
222 		return 0;
223 
224 	perf_pmu_migrate_context(&pmu_mmdc->pmu, cpu, target);
225 	cpumask_set_cpu(target, &pmu_mmdc->cpu);
226 
227 	return 0;
228 }
229 
230 static bool mmdc_pmu_group_event_is_valid(struct perf_event *event,
231 					  struct pmu *pmu,
232 					  unsigned long *used_counters)
233 {
234 	int cfg = event->attr.config;
235 
236 	if (is_software_event(event))
237 		return true;
238 
239 	if (event->pmu != pmu)
240 		return false;
241 
242 	return !test_and_set_bit(cfg, used_counters);
243 }
244 
245 /*
246  * Each event has a single fixed-purpose counter, so we can only have a
247  * single active event for each at any point in time. Here we just check
248  * for duplicates, and rely on mmdc_pmu_event_init to verify that the HW
249  * event numbers are valid.
250  */
251 static bool mmdc_pmu_group_is_valid(struct perf_event *event)
252 {
253 	struct pmu *pmu = event->pmu;
254 	struct perf_event *leader = event->group_leader;
255 	struct perf_event *sibling;
256 	unsigned long counter_mask = 0;
257 
258 	set_bit(leader->attr.config, &counter_mask);
259 
260 	if (event != leader) {
261 		if (!mmdc_pmu_group_event_is_valid(event, pmu, &counter_mask))
262 			return false;
263 	}
264 
265 	list_for_each_entry(sibling, &leader->sibling_list, group_entry) {
266 		if (!mmdc_pmu_group_event_is_valid(sibling, pmu, &counter_mask))
267 			return false;
268 	}
269 
270 	return true;
271 }
272 
273 static int mmdc_pmu_event_init(struct perf_event *event)
274 {
275 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
276 	int cfg = event->attr.config;
277 
278 	if (event->attr.type != event->pmu->type)
279 		return -ENOENT;
280 
281 	if (is_sampling_event(event) || event->attach_state & PERF_ATTACH_TASK)
282 		return -EOPNOTSUPP;
283 
284 	if (event->cpu < 0) {
285 		dev_warn(pmu_mmdc->dev, "Can't provide per-task data!\n");
286 		return -EOPNOTSUPP;
287 	}
288 
289 	if (event->attr.exclude_user		||
290 			event->attr.exclude_kernel	||
291 			event->attr.exclude_hv		||
292 			event->attr.exclude_idle	||
293 			event->attr.exclude_host	||
294 			event->attr.exclude_guest	||
295 			event->attr.sample_period)
296 		return -EINVAL;
297 
298 	if (cfg < 0 || cfg >= MMDC_NUM_COUNTERS)
299 		return -EINVAL;
300 
301 	if (!mmdc_pmu_group_is_valid(event))
302 		return -EINVAL;
303 
304 	event->cpu = cpumask_first(&pmu_mmdc->cpu);
305 	return 0;
306 }
307 
308 static void mmdc_pmu_event_update(struct perf_event *event)
309 {
310 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
311 	struct hw_perf_event *hwc = &event->hw;
312 	u64 delta, prev_raw_count, new_raw_count;
313 
314 	do {
315 		prev_raw_count = local64_read(&hwc->prev_count);
316 		new_raw_count = mmdc_pmu_read_counter(pmu_mmdc,
317 						      event->attr.config);
318 	} while (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
319 		new_raw_count) != prev_raw_count);
320 
321 	delta = (new_raw_count - prev_raw_count) & 0xFFFFFFFF;
322 
323 	local64_add(delta, &event->count);
324 }
325 
326 static void mmdc_pmu_event_start(struct perf_event *event, int flags)
327 {
328 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
329 	struct hw_perf_event *hwc = &event->hw;
330 	void __iomem *mmdc_base, *reg;
331 	u32 val;
332 
333 	mmdc_base = pmu_mmdc->mmdc_base;
334 	reg = mmdc_base + MMDC_MADPCR0;
335 
336 	/*
337 	 * hrtimer is required because mmdc does not provide an interrupt so
338 	 * polling is necessary
339 	 */
340 	hrtimer_start(&pmu_mmdc->hrtimer, mmdc_pmu_timer_period(),
341 			HRTIMER_MODE_REL_PINNED);
342 
343 	local64_set(&hwc->prev_count, 0);
344 
345 	writel(DBG_RST, reg);
346 
347 	val = DBG_EN;
348 	if (pmu_mmdc->devtype_data->flags & MMDC_FLAG_PROFILE_SEL)
349 		val |= PROFILE_SEL;
350 
351 	writel(val, reg);
352 }
353 
354 static int mmdc_pmu_event_add(struct perf_event *event, int flags)
355 {
356 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
357 	struct hw_perf_event *hwc = &event->hw;
358 
359 	int cfg = event->attr.config;
360 
361 	if (flags & PERF_EF_START)
362 		mmdc_pmu_event_start(event, flags);
363 
364 	if (pmu_mmdc->mmdc_events[cfg] != NULL)
365 		return -EAGAIN;
366 
367 	pmu_mmdc->mmdc_events[cfg] = event;
368 	pmu_mmdc->active_events++;
369 
370 	local64_set(&hwc->prev_count, mmdc_pmu_read_counter(pmu_mmdc, cfg));
371 
372 	return 0;
373 }
374 
375 static void mmdc_pmu_event_stop(struct perf_event *event, int flags)
376 {
377 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
378 	void __iomem *mmdc_base, *reg;
379 
380 	mmdc_base = pmu_mmdc->mmdc_base;
381 	reg = mmdc_base + MMDC_MADPCR0;
382 
383 	writel(PRF_FRZ, reg);
384 	mmdc_pmu_event_update(event);
385 }
386 
387 static void mmdc_pmu_event_del(struct perf_event *event, int flags)
388 {
389 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
390 	int cfg = event->attr.config;
391 
392 	pmu_mmdc->mmdc_events[cfg] = NULL;
393 	pmu_mmdc->active_events--;
394 
395 	if (pmu_mmdc->active_events == 0)
396 		hrtimer_cancel(&pmu_mmdc->hrtimer);
397 
398 	mmdc_pmu_event_stop(event, PERF_EF_UPDATE);
399 }
400 
401 static void mmdc_pmu_overflow_handler(struct mmdc_pmu *pmu_mmdc)
402 {
403 	int i;
404 
405 	for (i = 0; i < MMDC_NUM_COUNTERS; i++) {
406 		struct perf_event *event = pmu_mmdc->mmdc_events[i];
407 
408 		if (event)
409 			mmdc_pmu_event_update(event);
410 	}
411 }
412 
413 static enum hrtimer_restart mmdc_pmu_timer_handler(struct hrtimer *hrtimer)
414 {
415 	struct mmdc_pmu *pmu_mmdc = container_of(hrtimer, struct mmdc_pmu,
416 			hrtimer);
417 
418 	mmdc_pmu_overflow_handler(pmu_mmdc);
419 	hrtimer_forward_now(hrtimer, mmdc_pmu_timer_period());
420 
421 	return HRTIMER_RESTART;
422 }
423 
424 static int mmdc_pmu_init(struct mmdc_pmu *pmu_mmdc,
425 		void __iomem *mmdc_base, struct device *dev)
426 {
427 	int mmdc_num;
428 
429 	*pmu_mmdc = (struct mmdc_pmu) {
430 		.pmu = (struct pmu) {
431 			.task_ctx_nr    = perf_invalid_context,
432 			.attr_groups    = attr_groups,
433 			.event_init     = mmdc_pmu_event_init,
434 			.add            = mmdc_pmu_event_add,
435 			.del            = mmdc_pmu_event_del,
436 			.start          = mmdc_pmu_event_start,
437 			.stop           = mmdc_pmu_event_stop,
438 			.read           = mmdc_pmu_event_update,
439 		},
440 		.mmdc_base = mmdc_base,
441 		.dev = dev,
442 		.active_events = 0,
443 	};
444 
445 	mmdc_num = ida_simple_get(&mmdc_ida, 0, 0, GFP_KERNEL);
446 
447 	return mmdc_num;
448 }
449 
450 static int imx_mmdc_remove(struct platform_device *pdev)
451 {
452 	struct mmdc_pmu *pmu_mmdc = platform_get_drvdata(pdev);
453 
454 	perf_pmu_unregister(&pmu_mmdc->pmu);
455 	cpuhp_remove_state_nocalls(CPUHP_ONLINE);
456 	kfree(pmu_mmdc);
457 	return 0;
458 }
459 
460 static int imx_mmdc_perf_init(struct platform_device *pdev, void __iomem *mmdc_base)
461 {
462 	struct mmdc_pmu *pmu_mmdc;
463 	char *name;
464 	int mmdc_num;
465 	int ret;
466 	const struct of_device_id *of_id =
467 		of_match_device(imx_mmdc_dt_ids, &pdev->dev);
468 
469 	pmu_mmdc = kzalloc(sizeof(*pmu_mmdc), GFP_KERNEL);
470 	if (!pmu_mmdc) {
471 		pr_err("failed to allocate PMU device!\n");
472 		return -ENOMEM;
473 	}
474 
475 	mmdc_num = mmdc_pmu_init(pmu_mmdc, mmdc_base, &pdev->dev);
476 	if (mmdc_num == 0)
477 		name = "mmdc";
478 	else
479 		name = devm_kasprintf(&pdev->dev,
480 				GFP_KERNEL, "mmdc%d", mmdc_num);
481 
482 	pmu_mmdc->devtype_data = (struct fsl_mmdc_devtype_data *)of_id->data;
483 
484 	hrtimer_init(&pmu_mmdc->hrtimer, CLOCK_MONOTONIC,
485 			HRTIMER_MODE_REL);
486 	pmu_mmdc->hrtimer.function = mmdc_pmu_timer_handler;
487 
488 	cpuhp_state_add_instance_nocalls(CPUHP_ONLINE,
489 					 &pmu_mmdc->node);
490 	cpumask_set_cpu(smp_processor_id(), &pmu_mmdc->cpu);
491 	ret = cpuhp_setup_state_multi(CPUHP_AP_NOTIFY_ONLINE,
492 				      "MMDC_ONLINE", NULL,
493 				      mmdc_pmu_offline_cpu);
494 	if (ret) {
495 		pr_err("cpuhp_setup_state_multi failure\n");
496 		goto pmu_register_err;
497 	}
498 
499 	ret = perf_pmu_register(&(pmu_mmdc->pmu), name, -1);
500 	platform_set_drvdata(pdev, pmu_mmdc);
501 	if (ret)
502 		goto pmu_register_err;
503 	return 0;
504 
505 pmu_register_err:
506 	pr_warn("MMDC Perf PMU failed (%d), disabled\n", ret);
507 	hrtimer_cancel(&pmu_mmdc->hrtimer);
508 	kfree(pmu_mmdc);
509 	return ret;
510 }
511 
512 #else
513 #define imx_mmdc_remove NULL
514 #define imx_mmdc_perf_init(pdev, mmdc_base) 0
515 #endif
516 
517 static int imx_mmdc_probe(struct platform_device *pdev)
518 {
519 	struct device_node *np = pdev->dev.of_node;
520 	void __iomem *mmdc_base, *reg;
521 	u32 val;
522 	int timeout = 0x400;
523 
524 	mmdc_base = of_iomap(np, 0);
525 	WARN_ON(!mmdc_base);
526 
527 	reg = mmdc_base + MMDC_MDMISC;
528 	/* Get ddr type */
529 	val = readl_relaxed(reg);
530 	ddr_type = (val & BM_MMDC_MDMISC_DDR_TYPE) >>
531 		 BP_MMDC_MDMISC_DDR_TYPE;
532 
533 	reg = mmdc_base + MMDC_MAPSR;
534 
535 	/* Enable automatic power saving */
536 	val = readl_relaxed(reg);
537 	val &= ~(1 << BP_MMDC_MAPSR_PSD);
538 	writel_relaxed(val, reg);
539 
540 	/* Ensure it's successfully enabled */
541 	while (!(readl_relaxed(reg) & 1 << BP_MMDC_MAPSR_PSS) && --timeout)
542 		cpu_relax();
543 
544 	if (unlikely(!timeout)) {
545 		pr_warn("%s: failed to enable automatic power saving\n",
546 			__func__);
547 		return -EBUSY;
548 	}
549 
550 	return imx_mmdc_perf_init(pdev, mmdc_base);
551 }
552 
553 int imx_mmdc_get_ddr_type(void)
554 {
555 	return ddr_type;
556 }
557 
558 static struct platform_driver imx_mmdc_driver = {
559 	.driver		= {
560 		.name	= "imx-mmdc",
561 		.of_match_table = imx_mmdc_dt_ids,
562 	},
563 	.probe		= imx_mmdc_probe,
564 	.remove		= imx_mmdc_remove,
565 };
566 
567 static int __init imx_mmdc_init(void)
568 {
569 	return platform_driver_register(&imx_mmdc_driver);
570 }
571 postcore_initcall(imx_mmdc_init);
572