xref: /openbmc/linux/arch/arm/mach-imx/mmdc.c (revision dd5b2498)
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/clk.h>
15 #include <linux/hrtimer.h>
16 #include <linux/init.h>
17 #include <linux/interrupt.h>
18 #include <linux/io.h>
19 #include <linux/module.h>
20 #include <linux/of.h>
21 #include <linux/of_address.h>
22 #include <linux/of_device.h>
23 #include <linux/perf_event.h>
24 #include <linux/slab.h>
25 
26 #include "common.h"
27 
28 #define MMDC_MAPSR		0x404
29 #define BP_MMDC_MAPSR_PSD	0
30 #define BP_MMDC_MAPSR_PSS	4
31 
32 #define MMDC_MDMISC		0x18
33 #define BM_MMDC_MDMISC_DDR_TYPE	0x18
34 #define BP_MMDC_MDMISC_DDR_TYPE	0x3
35 
36 #define TOTAL_CYCLES		0x0
37 #define BUSY_CYCLES		0x1
38 #define READ_ACCESSES		0x2
39 #define WRITE_ACCESSES		0x3
40 #define READ_BYTES		0x4
41 #define WRITE_BYTES		0x5
42 
43 /* Enables, resets, freezes, overflow profiling*/
44 #define DBG_DIS			0x0
45 #define DBG_EN			0x1
46 #define DBG_RST			0x2
47 #define PRF_FRZ			0x4
48 #define CYC_OVF			0x8
49 #define PROFILE_SEL		0x10
50 
51 #define MMDC_MADPCR0	0x410
52 #define MMDC_MADPCR1	0x414
53 #define MMDC_MADPSR0	0x418
54 #define MMDC_MADPSR1	0x41C
55 #define MMDC_MADPSR2	0x420
56 #define MMDC_MADPSR3	0x424
57 #define MMDC_MADPSR4	0x428
58 #define MMDC_MADPSR5	0x42C
59 
60 #define MMDC_NUM_COUNTERS	6
61 
62 #define MMDC_FLAG_PROFILE_SEL	0x1
63 #define MMDC_PRF_AXI_ID_CLEAR	0x0
64 
65 #define to_mmdc_pmu(p) container_of(p, struct mmdc_pmu, pmu)
66 
67 static int ddr_type;
68 
69 struct fsl_mmdc_devtype_data {
70 	unsigned int flags;
71 };
72 
73 static const struct fsl_mmdc_devtype_data imx6q_data = {
74 };
75 
76 static const struct fsl_mmdc_devtype_data imx6qp_data = {
77 	.flags = MMDC_FLAG_PROFILE_SEL,
78 };
79 
80 static const struct of_device_id imx_mmdc_dt_ids[] = {
81 	{ .compatible = "fsl,imx6q-mmdc", .data = (void *)&imx6q_data},
82 	{ .compatible = "fsl,imx6qp-mmdc", .data = (void *)&imx6qp_data},
83 	{ /* sentinel */ }
84 };
85 
86 #ifdef CONFIG_PERF_EVENTS
87 
88 static enum cpuhp_state cpuhp_mmdc_state;
89 static DEFINE_IDA(mmdc_ida);
90 
91 PMU_EVENT_ATTR_STRING(total-cycles, mmdc_pmu_total_cycles, "event=0x00")
92 PMU_EVENT_ATTR_STRING(busy-cycles, mmdc_pmu_busy_cycles, "event=0x01")
93 PMU_EVENT_ATTR_STRING(read-accesses, mmdc_pmu_read_accesses, "event=0x02")
94 PMU_EVENT_ATTR_STRING(write-accesses, mmdc_pmu_write_accesses, "event=0x03")
95 PMU_EVENT_ATTR_STRING(read-bytes, mmdc_pmu_read_bytes, "event=0x04")
96 PMU_EVENT_ATTR_STRING(read-bytes.unit, mmdc_pmu_read_bytes_unit, "MB");
97 PMU_EVENT_ATTR_STRING(read-bytes.scale, mmdc_pmu_read_bytes_scale, "0.000001");
98 PMU_EVENT_ATTR_STRING(write-bytes, mmdc_pmu_write_bytes, "event=0x05")
99 PMU_EVENT_ATTR_STRING(write-bytes.unit, mmdc_pmu_write_bytes_unit, "MB");
100 PMU_EVENT_ATTR_STRING(write-bytes.scale, mmdc_pmu_write_bytes_scale, "0.000001");
101 
102 struct mmdc_pmu {
103 	struct pmu pmu;
104 	void __iomem *mmdc_base;
105 	cpumask_t cpu;
106 	struct hrtimer hrtimer;
107 	unsigned int active_events;
108 	struct device *dev;
109 	struct perf_event *mmdc_events[MMDC_NUM_COUNTERS];
110 	struct hlist_node node;
111 	struct fsl_mmdc_devtype_data *devtype_data;
112 };
113 
114 /*
115  * Polling period is set to one second, overflow of total-cycles (the fastest
116  * increasing counter) takes ten seconds so one second is safe
117  */
118 static unsigned int mmdc_pmu_poll_period_us = 1000000;
119 
120 module_param_named(pmu_pmu_poll_period_us, mmdc_pmu_poll_period_us, uint,
121 		S_IRUGO | S_IWUSR);
122 
123 static ktime_t mmdc_pmu_timer_period(void)
124 {
125 	return ns_to_ktime((u64)mmdc_pmu_poll_period_us * 1000);
126 }
127 
128 static ssize_t mmdc_pmu_cpumask_show(struct device *dev,
129 		struct device_attribute *attr, char *buf)
130 {
131 	struct mmdc_pmu *pmu_mmdc = dev_get_drvdata(dev);
132 
133 	return cpumap_print_to_pagebuf(true, buf, &pmu_mmdc->cpu);
134 }
135 
136 static struct device_attribute mmdc_pmu_cpumask_attr =
137 	__ATTR(cpumask, S_IRUGO, mmdc_pmu_cpumask_show, NULL);
138 
139 static struct attribute *mmdc_pmu_cpumask_attrs[] = {
140 	&mmdc_pmu_cpumask_attr.attr,
141 	NULL,
142 };
143 
144 static struct attribute_group mmdc_pmu_cpumask_attr_group = {
145 	.attrs = mmdc_pmu_cpumask_attrs,
146 };
147 
148 static struct attribute *mmdc_pmu_events_attrs[] = {
149 	&mmdc_pmu_total_cycles.attr.attr,
150 	&mmdc_pmu_busy_cycles.attr.attr,
151 	&mmdc_pmu_read_accesses.attr.attr,
152 	&mmdc_pmu_write_accesses.attr.attr,
153 	&mmdc_pmu_read_bytes.attr.attr,
154 	&mmdc_pmu_read_bytes_unit.attr.attr,
155 	&mmdc_pmu_read_bytes_scale.attr.attr,
156 	&mmdc_pmu_write_bytes.attr.attr,
157 	&mmdc_pmu_write_bytes_unit.attr.attr,
158 	&mmdc_pmu_write_bytes_scale.attr.attr,
159 	NULL,
160 };
161 
162 static struct attribute_group mmdc_pmu_events_attr_group = {
163 	.name = "events",
164 	.attrs = mmdc_pmu_events_attrs,
165 };
166 
167 PMU_FORMAT_ATTR(event, "config:0-63");
168 PMU_FORMAT_ATTR(axi_id, "config1:0-63");
169 
170 static struct attribute *mmdc_pmu_format_attrs[] = {
171 	&format_attr_event.attr,
172 	&format_attr_axi_id.attr,
173 	NULL,
174 };
175 
176 static struct attribute_group mmdc_pmu_format_attr_group = {
177 	.name = "format",
178 	.attrs = mmdc_pmu_format_attrs,
179 };
180 
181 static const struct attribute_group *attr_groups[] = {
182 	&mmdc_pmu_events_attr_group,
183 	&mmdc_pmu_format_attr_group,
184 	&mmdc_pmu_cpumask_attr_group,
185 	NULL,
186 };
187 
188 static u32 mmdc_pmu_read_counter(struct mmdc_pmu *pmu_mmdc, int cfg)
189 {
190 	void __iomem *mmdc_base, *reg;
191 
192 	mmdc_base = pmu_mmdc->mmdc_base;
193 
194 	switch (cfg) {
195 	case TOTAL_CYCLES:
196 		reg = mmdc_base + MMDC_MADPSR0;
197 		break;
198 	case BUSY_CYCLES:
199 		reg = mmdc_base + MMDC_MADPSR1;
200 		break;
201 	case READ_ACCESSES:
202 		reg = mmdc_base + MMDC_MADPSR2;
203 		break;
204 	case WRITE_ACCESSES:
205 		reg = mmdc_base + MMDC_MADPSR3;
206 		break;
207 	case READ_BYTES:
208 		reg = mmdc_base + MMDC_MADPSR4;
209 		break;
210 	case WRITE_BYTES:
211 		reg = mmdc_base + MMDC_MADPSR5;
212 		break;
213 	default:
214 		return WARN_ONCE(1,
215 			"invalid configuration %d for mmdc counter", cfg);
216 	}
217 	return readl(reg);
218 }
219 
220 static int mmdc_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
221 {
222 	struct mmdc_pmu *pmu_mmdc = hlist_entry_safe(node, struct mmdc_pmu, node);
223 	int target;
224 
225 	if (!cpumask_test_and_clear_cpu(cpu, &pmu_mmdc->cpu))
226 		return 0;
227 
228 	target = cpumask_any_but(cpu_online_mask, cpu);
229 	if (target >= nr_cpu_ids)
230 		return 0;
231 
232 	perf_pmu_migrate_context(&pmu_mmdc->pmu, cpu, target);
233 	cpumask_set_cpu(target, &pmu_mmdc->cpu);
234 
235 	return 0;
236 }
237 
238 static bool mmdc_pmu_group_event_is_valid(struct perf_event *event,
239 					  struct pmu *pmu,
240 					  unsigned long *used_counters)
241 {
242 	int cfg = event->attr.config;
243 
244 	if (is_software_event(event))
245 		return true;
246 
247 	if (event->pmu != pmu)
248 		return false;
249 
250 	return !test_and_set_bit(cfg, used_counters);
251 }
252 
253 /*
254  * Each event has a single fixed-purpose counter, so we can only have a
255  * single active event for each at any point in time. Here we just check
256  * for duplicates, and rely on mmdc_pmu_event_init to verify that the HW
257  * event numbers are valid.
258  */
259 static bool mmdc_pmu_group_is_valid(struct perf_event *event)
260 {
261 	struct pmu *pmu = event->pmu;
262 	struct perf_event *leader = event->group_leader;
263 	struct perf_event *sibling;
264 	unsigned long counter_mask = 0;
265 
266 	set_bit(leader->attr.config, &counter_mask);
267 
268 	if (event != leader) {
269 		if (!mmdc_pmu_group_event_is_valid(event, pmu, &counter_mask))
270 			return false;
271 	}
272 
273 	for_each_sibling_event(sibling, leader) {
274 		if (!mmdc_pmu_group_event_is_valid(sibling, pmu, &counter_mask))
275 			return false;
276 	}
277 
278 	return true;
279 }
280 
281 static int mmdc_pmu_event_init(struct perf_event *event)
282 {
283 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
284 	int cfg = event->attr.config;
285 
286 	if (event->attr.type != event->pmu->type)
287 		return -ENOENT;
288 
289 	if (is_sampling_event(event) || event->attach_state & PERF_ATTACH_TASK)
290 		return -EOPNOTSUPP;
291 
292 	if (event->cpu < 0) {
293 		dev_warn(pmu_mmdc->dev, "Can't provide per-task data!\n");
294 		return -EOPNOTSUPP;
295 	}
296 
297 	if (event->attr.sample_period)
298 		return -EINVAL;
299 
300 	if (cfg < 0 || cfg >= MMDC_NUM_COUNTERS)
301 		return -EINVAL;
302 
303 	if (!mmdc_pmu_group_is_valid(event))
304 		return -EINVAL;
305 
306 	event->cpu = cpumask_first(&pmu_mmdc->cpu);
307 	return 0;
308 }
309 
310 static void mmdc_pmu_event_update(struct perf_event *event)
311 {
312 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
313 	struct hw_perf_event *hwc = &event->hw;
314 	u64 delta, prev_raw_count, new_raw_count;
315 
316 	do {
317 		prev_raw_count = local64_read(&hwc->prev_count);
318 		new_raw_count = mmdc_pmu_read_counter(pmu_mmdc,
319 						      event->attr.config);
320 	} while (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
321 		new_raw_count) != prev_raw_count);
322 
323 	delta = (new_raw_count - prev_raw_count) & 0xFFFFFFFF;
324 
325 	local64_add(delta, &event->count);
326 }
327 
328 static void mmdc_pmu_event_start(struct perf_event *event, int flags)
329 {
330 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
331 	struct hw_perf_event *hwc = &event->hw;
332 	void __iomem *mmdc_base, *reg;
333 	u32 val;
334 
335 	mmdc_base = pmu_mmdc->mmdc_base;
336 	reg = mmdc_base + MMDC_MADPCR0;
337 
338 	/*
339 	 * hrtimer is required because mmdc does not provide an interrupt so
340 	 * polling is necessary
341 	 */
342 	hrtimer_start(&pmu_mmdc->hrtimer, mmdc_pmu_timer_period(),
343 			HRTIMER_MODE_REL_PINNED);
344 
345 	local64_set(&hwc->prev_count, 0);
346 
347 	writel(DBG_RST, reg);
348 
349 	/*
350 	 * Write the AXI id parameter to MADPCR1.
351 	 */
352 	val = event->attr.config1;
353 	reg = mmdc_base + MMDC_MADPCR1;
354 	writel(val, reg);
355 
356 	reg = mmdc_base + MMDC_MADPCR0;
357 	val = DBG_EN;
358 	if (pmu_mmdc->devtype_data->flags & MMDC_FLAG_PROFILE_SEL)
359 		val |= PROFILE_SEL;
360 
361 	writel(val, reg);
362 }
363 
364 static int mmdc_pmu_event_add(struct perf_event *event, int flags)
365 {
366 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
367 	struct hw_perf_event *hwc = &event->hw;
368 
369 	int cfg = event->attr.config;
370 
371 	if (flags & PERF_EF_START)
372 		mmdc_pmu_event_start(event, flags);
373 
374 	if (pmu_mmdc->mmdc_events[cfg] != NULL)
375 		return -EAGAIN;
376 
377 	pmu_mmdc->mmdc_events[cfg] = event;
378 	pmu_mmdc->active_events++;
379 
380 	local64_set(&hwc->prev_count, mmdc_pmu_read_counter(pmu_mmdc, cfg));
381 
382 	return 0;
383 }
384 
385 static void mmdc_pmu_event_stop(struct perf_event *event, int flags)
386 {
387 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
388 	void __iomem *mmdc_base, *reg;
389 
390 	mmdc_base = pmu_mmdc->mmdc_base;
391 	reg = mmdc_base + MMDC_MADPCR0;
392 
393 	writel(PRF_FRZ, reg);
394 
395 	reg = mmdc_base + MMDC_MADPCR1;
396 	writel(MMDC_PRF_AXI_ID_CLEAR, reg);
397 
398 	mmdc_pmu_event_update(event);
399 }
400 
401 static void mmdc_pmu_event_del(struct perf_event *event, int flags)
402 {
403 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
404 	int cfg = event->attr.config;
405 
406 	pmu_mmdc->mmdc_events[cfg] = NULL;
407 	pmu_mmdc->active_events--;
408 
409 	if (pmu_mmdc->active_events == 0)
410 		hrtimer_cancel(&pmu_mmdc->hrtimer);
411 
412 	mmdc_pmu_event_stop(event, PERF_EF_UPDATE);
413 }
414 
415 static void mmdc_pmu_overflow_handler(struct mmdc_pmu *pmu_mmdc)
416 {
417 	int i;
418 
419 	for (i = 0; i < MMDC_NUM_COUNTERS; i++) {
420 		struct perf_event *event = pmu_mmdc->mmdc_events[i];
421 
422 		if (event)
423 			mmdc_pmu_event_update(event);
424 	}
425 }
426 
427 static enum hrtimer_restart mmdc_pmu_timer_handler(struct hrtimer *hrtimer)
428 {
429 	struct mmdc_pmu *pmu_mmdc = container_of(hrtimer, struct mmdc_pmu,
430 			hrtimer);
431 
432 	mmdc_pmu_overflow_handler(pmu_mmdc);
433 	hrtimer_forward_now(hrtimer, mmdc_pmu_timer_period());
434 
435 	return HRTIMER_RESTART;
436 }
437 
438 static int mmdc_pmu_init(struct mmdc_pmu *pmu_mmdc,
439 		void __iomem *mmdc_base, struct device *dev)
440 {
441 	int mmdc_num;
442 
443 	*pmu_mmdc = (struct mmdc_pmu) {
444 		.pmu = (struct pmu) {
445 			.task_ctx_nr    = perf_invalid_context,
446 			.attr_groups    = attr_groups,
447 			.event_init     = mmdc_pmu_event_init,
448 			.add            = mmdc_pmu_event_add,
449 			.del            = mmdc_pmu_event_del,
450 			.start          = mmdc_pmu_event_start,
451 			.stop           = mmdc_pmu_event_stop,
452 			.read           = mmdc_pmu_event_update,
453 			.capabilities	= PERF_PMU_CAP_NO_EXCLUDE,
454 		},
455 		.mmdc_base = mmdc_base,
456 		.dev = dev,
457 		.active_events = 0,
458 	};
459 
460 	mmdc_num = ida_simple_get(&mmdc_ida, 0, 0, GFP_KERNEL);
461 
462 	return mmdc_num;
463 }
464 
465 static int imx_mmdc_remove(struct platform_device *pdev)
466 {
467 	struct mmdc_pmu *pmu_mmdc = platform_get_drvdata(pdev);
468 
469 	cpuhp_state_remove_instance_nocalls(cpuhp_mmdc_state, &pmu_mmdc->node);
470 	perf_pmu_unregister(&pmu_mmdc->pmu);
471 	kfree(pmu_mmdc);
472 	return 0;
473 }
474 
475 static int imx_mmdc_perf_init(struct platform_device *pdev, void __iomem *mmdc_base)
476 {
477 	struct mmdc_pmu *pmu_mmdc;
478 	char *name;
479 	int mmdc_num;
480 	int ret;
481 	const struct of_device_id *of_id =
482 		of_match_device(imx_mmdc_dt_ids, &pdev->dev);
483 
484 	pmu_mmdc = kzalloc(sizeof(*pmu_mmdc), GFP_KERNEL);
485 	if (!pmu_mmdc) {
486 		pr_err("failed to allocate PMU device!\n");
487 		return -ENOMEM;
488 	}
489 
490 	/* The first instance registers the hotplug state */
491 	if (!cpuhp_mmdc_state) {
492 		ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN,
493 					      "perf/arm/mmdc:online", NULL,
494 					      mmdc_pmu_offline_cpu);
495 		if (ret < 0) {
496 			pr_err("cpuhp_setup_state_multi failed\n");
497 			goto pmu_free;
498 		}
499 		cpuhp_mmdc_state = ret;
500 	}
501 
502 	mmdc_num = mmdc_pmu_init(pmu_mmdc, mmdc_base, &pdev->dev);
503 	if (mmdc_num == 0)
504 		name = "mmdc";
505 	else
506 		name = devm_kasprintf(&pdev->dev,
507 				GFP_KERNEL, "mmdc%d", mmdc_num);
508 
509 	pmu_mmdc->devtype_data = (struct fsl_mmdc_devtype_data *)of_id->data;
510 
511 	hrtimer_init(&pmu_mmdc->hrtimer, CLOCK_MONOTONIC,
512 			HRTIMER_MODE_REL);
513 	pmu_mmdc->hrtimer.function = mmdc_pmu_timer_handler;
514 
515 	cpumask_set_cpu(raw_smp_processor_id(), &pmu_mmdc->cpu);
516 
517 	/* Register the pmu instance for cpu hotplug */
518 	cpuhp_state_add_instance_nocalls(cpuhp_mmdc_state, &pmu_mmdc->node);
519 
520 	ret = perf_pmu_register(&(pmu_mmdc->pmu), name, -1);
521 	if (ret)
522 		goto pmu_register_err;
523 
524 	platform_set_drvdata(pdev, pmu_mmdc);
525 	return 0;
526 
527 pmu_register_err:
528 	pr_warn("MMDC Perf PMU failed (%d), disabled\n", ret);
529 	cpuhp_state_remove_instance_nocalls(cpuhp_mmdc_state, &pmu_mmdc->node);
530 	hrtimer_cancel(&pmu_mmdc->hrtimer);
531 pmu_free:
532 	kfree(pmu_mmdc);
533 	return ret;
534 }
535 
536 #else
537 #define imx_mmdc_remove NULL
538 #define imx_mmdc_perf_init(pdev, mmdc_base) 0
539 #endif
540 
541 static int imx_mmdc_probe(struct platform_device *pdev)
542 {
543 	struct device_node *np = pdev->dev.of_node;
544 	void __iomem *mmdc_base, *reg;
545 	struct clk *mmdc_ipg_clk;
546 	u32 val;
547 	int err;
548 
549 	/* the ipg clock is optional */
550 	mmdc_ipg_clk = devm_clk_get(&pdev->dev, NULL);
551 	if (IS_ERR(mmdc_ipg_clk))
552 		mmdc_ipg_clk = NULL;
553 
554 	err = clk_prepare_enable(mmdc_ipg_clk);
555 	if (err) {
556 		dev_err(&pdev->dev, "Unable to enable mmdc ipg clock.\n");
557 		return err;
558 	}
559 
560 	mmdc_base = of_iomap(np, 0);
561 	WARN_ON(!mmdc_base);
562 
563 	reg = mmdc_base + MMDC_MDMISC;
564 	/* Get ddr type */
565 	val = readl_relaxed(reg);
566 	ddr_type = (val & BM_MMDC_MDMISC_DDR_TYPE) >>
567 		 BP_MMDC_MDMISC_DDR_TYPE;
568 
569 	reg = mmdc_base + MMDC_MAPSR;
570 
571 	/* Enable automatic power saving */
572 	val = readl_relaxed(reg);
573 	val &= ~(1 << BP_MMDC_MAPSR_PSD);
574 	writel_relaxed(val, reg);
575 
576 	return imx_mmdc_perf_init(pdev, mmdc_base);
577 }
578 
579 int imx_mmdc_get_ddr_type(void)
580 {
581 	return ddr_type;
582 }
583 
584 static struct platform_driver imx_mmdc_driver = {
585 	.driver		= {
586 		.name	= "imx-mmdc",
587 		.of_match_table = imx_mmdc_dt_ids,
588 	},
589 	.probe		= imx_mmdc_probe,
590 	.remove		= imx_mmdc_remove,
591 };
592 
593 static int __init imx_mmdc_init(void)
594 {
595 	return platform_driver_register(&imx_mmdc_driver);
596 }
597 postcore_initcall(imx_mmdc_init);
598