xref: /openbmc/linux/arch/arm/mach-imx/mmdc.c (revision 8dde5715)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright 2017 NXP
4  * Copyright 2011,2016 Freescale Semiconductor, Inc.
5  * Copyright 2011 Linaro Ltd.
6  */
7 
8 #include <linux/clk.h>
9 #include <linux/hrtimer.h>
10 #include <linux/init.h>
11 #include <linux/interrupt.h>
12 #include <linux/io.h>
13 #include <linux/module.h>
14 #include <linux/of.h>
15 #include <linux/of_address.h>
16 #include <linux/of_device.h>
17 #include <linux/perf_event.h>
18 #include <linux/slab.h>
19 
20 #include "common.h"
21 
22 #define MMDC_MAPSR		0x404
23 #define BP_MMDC_MAPSR_PSD	0
24 #define BP_MMDC_MAPSR_PSS	4
25 
26 #define MMDC_MDMISC		0x18
27 #define BM_MMDC_MDMISC_DDR_TYPE	0x18
28 #define BP_MMDC_MDMISC_DDR_TYPE	0x3
29 
30 #define TOTAL_CYCLES		0x0
31 #define BUSY_CYCLES		0x1
32 #define READ_ACCESSES		0x2
33 #define WRITE_ACCESSES		0x3
34 #define READ_BYTES		0x4
35 #define WRITE_BYTES		0x5
36 
37 /* Enables, resets, freezes, overflow profiling*/
38 #define DBG_DIS			0x0
39 #define DBG_EN			0x1
40 #define DBG_RST			0x2
41 #define PRF_FRZ			0x4
42 #define CYC_OVF			0x8
43 #define PROFILE_SEL		0x10
44 
45 #define MMDC_MADPCR0	0x410
46 #define MMDC_MADPCR1	0x414
47 #define MMDC_MADPSR0	0x418
48 #define MMDC_MADPSR1	0x41C
49 #define MMDC_MADPSR2	0x420
50 #define MMDC_MADPSR3	0x424
51 #define MMDC_MADPSR4	0x428
52 #define MMDC_MADPSR5	0x42C
53 
54 #define MMDC_NUM_COUNTERS	6
55 
56 #define MMDC_FLAG_PROFILE_SEL	0x1
57 #define MMDC_PRF_AXI_ID_CLEAR	0x0
58 
59 #define to_mmdc_pmu(p) container_of(p, struct mmdc_pmu, pmu)
60 
61 static int ddr_type;
62 
63 struct fsl_mmdc_devtype_data {
64 	unsigned int flags;
65 };
66 
67 static const struct fsl_mmdc_devtype_data imx6q_data = {
68 };
69 
70 static const struct fsl_mmdc_devtype_data imx6qp_data = {
71 	.flags = MMDC_FLAG_PROFILE_SEL,
72 };
73 
74 static const struct of_device_id imx_mmdc_dt_ids[] = {
75 	{ .compatible = "fsl,imx6q-mmdc", .data = (void *)&imx6q_data},
76 	{ .compatible = "fsl,imx6qp-mmdc", .data = (void *)&imx6qp_data},
77 	{ /* sentinel */ }
78 };
79 
80 #ifdef CONFIG_PERF_EVENTS
81 
82 static enum cpuhp_state cpuhp_mmdc_state;
83 static DEFINE_IDA(mmdc_ida);
84 
85 PMU_EVENT_ATTR_STRING(total-cycles, mmdc_pmu_total_cycles, "event=0x00")
86 PMU_EVENT_ATTR_STRING(busy-cycles, mmdc_pmu_busy_cycles, "event=0x01")
87 PMU_EVENT_ATTR_STRING(read-accesses, mmdc_pmu_read_accesses, "event=0x02")
88 PMU_EVENT_ATTR_STRING(write-accesses, mmdc_pmu_write_accesses, "event=0x03")
89 PMU_EVENT_ATTR_STRING(read-bytes, mmdc_pmu_read_bytes, "event=0x04")
90 PMU_EVENT_ATTR_STRING(read-bytes.unit, mmdc_pmu_read_bytes_unit, "MB");
91 PMU_EVENT_ATTR_STRING(read-bytes.scale, mmdc_pmu_read_bytes_scale, "0.000001");
92 PMU_EVENT_ATTR_STRING(write-bytes, mmdc_pmu_write_bytes, "event=0x05")
93 PMU_EVENT_ATTR_STRING(write-bytes.unit, mmdc_pmu_write_bytes_unit, "MB");
94 PMU_EVENT_ATTR_STRING(write-bytes.scale, mmdc_pmu_write_bytes_scale, "0.000001");
95 
96 struct mmdc_pmu {
97 	struct pmu pmu;
98 	void __iomem *mmdc_base;
99 	cpumask_t cpu;
100 	struct hrtimer hrtimer;
101 	unsigned int active_events;
102 	struct device *dev;
103 	struct perf_event *mmdc_events[MMDC_NUM_COUNTERS];
104 	struct hlist_node node;
105 	struct fsl_mmdc_devtype_data *devtype_data;
106 };
107 
108 /*
109  * Polling period is set to one second, overflow of total-cycles (the fastest
110  * increasing counter) takes ten seconds so one second is safe
111  */
112 static unsigned int mmdc_pmu_poll_period_us = 1000000;
113 
114 module_param_named(pmu_pmu_poll_period_us, mmdc_pmu_poll_period_us, uint,
115 		S_IRUGO | S_IWUSR);
116 
117 static ktime_t mmdc_pmu_timer_period(void)
118 {
119 	return ns_to_ktime((u64)mmdc_pmu_poll_period_us * 1000);
120 }
121 
122 static ssize_t mmdc_pmu_cpumask_show(struct device *dev,
123 		struct device_attribute *attr, char *buf)
124 {
125 	struct mmdc_pmu *pmu_mmdc = dev_get_drvdata(dev);
126 
127 	return cpumap_print_to_pagebuf(true, buf, &pmu_mmdc->cpu);
128 }
129 
130 static struct device_attribute mmdc_pmu_cpumask_attr =
131 	__ATTR(cpumask, S_IRUGO, mmdc_pmu_cpumask_show, NULL);
132 
133 static struct attribute *mmdc_pmu_cpumask_attrs[] = {
134 	&mmdc_pmu_cpumask_attr.attr,
135 	NULL,
136 };
137 
138 static struct attribute_group mmdc_pmu_cpumask_attr_group = {
139 	.attrs = mmdc_pmu_cpumask_attrs,
140 };
141 
142 static struct attribute *mmdc_pmu_events_attrs[] = {
143 	&mmdc_pmu_total_cycles.attr.attr,
144 	&mmdc_pmu_busy_cycles.attr.attr,
145 	&mmdc_pmu_read_accesses.attr.attr,
146 	&mmdc_pmu_write_accesses.attr.attr,
147 	&mmdc_pmu_read_bytes.attr.attr,
148 	&mmdc_pmu_read_bytes_unit.attr.attr,
149 	&mmdc_pmu_read_bytes_scale.attr.attr,
150 	&mmdc_pmu_write_bytes.attr.attr,
151 	&mmdc_pmu_write_bytes_unit.attr.attr,
152 	&mmdc_pmu_write_bytes_scale.attr.attr,
153 	NULL,
154 };
155 
156 static struct attribute_group mmdc_pmu_events_attr_group = {
157 	.name = "events",
158 	.attrs = mmdc_pmu_events_attrs,
159 };
160 
161 PMU_FORMAT_ATTR(event, "config:0-63");
162 PMU_FORMAT_ATTR(axi_id, "config1:0-63");
163 
164 static struct attribute *mmdc_pmu_format_attrs[] = {
165 	&format_attr_event.attr,
166 	&format_attr_axi_id.attr,
167 	NULL,
168 };
169 
170 static struct attribute_group mmdc_pmu_format_attr_group = {
171 	.name = "format",
172 	.attrs = mmdc_pmu_format_attrs,
173 };
174 
175 static const struct attribute_group *attr_groups[] = {
176 	&mmdc_pmu_events_attr_group,
177 	&mmdc_pmu_format_attr_group,
178 	&mmdc_pmu_cpumask_attr_group,
179 	NULL,
180 };
181 
182 static u32 mmdc_pmu_read_counter(struct mmdc_pmu *pmu_mmdc, int cfg)
183 {
184 	void __iomem *mmdc_base, *reg;
185 
186 	mmdc_base = pmu_mmdc->mmdc_base;
187 
188 	switch (cfg) {
189 	case TOTAL_CYCLES:
190 		reg = mmdc_base + MMDC_MADPSR0;
191 		break;
192 	case BUSY_CYCLES:
193 		reg = mmdc_base + MMDC_MADPSR1;
194 		break;
195 	case READ_ACCESSES:
196 		reg = mmdc_base + MMDC_MADPSR2;
197 		break;
198 	case WRITE_ACCESSES:
199 		reg = mmdc_base + MMDC_MADPSR3;
200 		break;
201 	case READ_BYTES:
202 		reg = mmdc_base + MMDC_MADPSR4;
203 		break;
204 	case WRITE_BYTES:
205 		reg = mmdc_base + MMDC_MADPSR5;
206 		break;
207 	default:
208 		return WARN_ONCE(1,
209 			"invalid configuration %d for mmdc counter", cfg);
210 	}
211 	return readl(reg);
212 }
213 
214 static int mmdc_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
215 {
216 	struct mmdc_pmu *pmu_mmdc = hlist_entry_safe(node, struct mmdc_pmu, node);
217 	int target;
218 
219 	if (!cpumask_test_and_clear_cpu(cpu, &pmu_mmdc->cpu))
220 		return 0;
221 
222 	target = cpumask_any_but(cpu_online_mask, cpu);
223 	if (target >= nr_cpu_ids)
224 		return 0;
225 
226 	perf_pmu_migrate_context(&pmu_mmdc->pmu, cpu, target);
227 	cpumask_set_cpu(target, &pmu_mmdc->cpu);
228 
229 	return 0;
230 }
231 
232 static bool mmdc_pmu_group_event_is_valid(struct perf_event *event,
233 					  struct pmu *pmu,
234 					  unsigned long *used_counters)
235 {
236 	int cfg = event->attr.config;
237 
238 	if (is_software_event(event))
239 		return true;
240 
241 	if (event->pmu != pmu)
242 		return false;
243 
244 	return !test_and_set_bit(cfg, used_counters);
245 }
246 
247 /*
248  * Each event has a single fixed-purpose counter, so we can only have a
249  * single active event for each at any point in time. Here we just check
250  * for duplicates, and rely on mmdc_pmu_event_init to verify that the HW
251  * event numbers are valid.
252  */
253 static bool mmdc_pmu_group_is_valid(struct perf_event *event)
254 {
255 	struct pmu *pmu = event->pmu;
256 	struct perf_event *leader = event->group_leader;
257 	struct perf_event *sibling;
258 	unsigned long counter_mask = 0;
259 
260 	set_bit(leader->attr.config, &counter_mask);
261 
262 	if (event != leader) {
263 		if (!mmdc_pmu_group_event_is_valid(event, pmu, &counter_mask))
264 			return false;
265 	}
266 
267 	for_each_sibling_event(sibling, leader) {
268 		if (!mmdc_pmu_group_event_is_valid(sibling, pmu, &counter_mask))
269 			return false;
270 	}
271 
272 	return true;
273 }
274 
275 static int mmdc_pmu_event_init(struct perf_event *event)
276 {
277 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
278 	int cfg = event->attr.config;
279 
280 	if (event->attr.type != event->pmu->type)
281 		return -ENOENT;
282 
283 	if (is_sampling_event(event) || event->attach_state & PERF_ATTACH_TASK)
284 		return -EOPNOTSUPP;
285 
286 	if (event->cpu < 0) {
287 		dev_warn(pmu_mmdc->dev, "Can't provide per-task data!\n");
288 		return -EOPNOTSUPP;
289 	}
290 
291 	if (event->attr.sample_period)
292 		return -EINVAL;
293 
294 	if (cfg < 0 || cfg >= MMDC_NUM_COUNTERS)
295 		return -EINVAL;
296 
297 	if (!mmdc_pmu_group_is_valid(event))
298 		return -EINVAL;
299 
300 	event->cpu = cpumask_first(&pmu_mmdc->cpu);
301 	return 0;
302 }
303 
304 static void mmdc_pmu_event_update(struct perf_event *event)
305 {
306 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
307 	struct hw_perf_event *hwc = &event->hw;
308 	u64 delta, prev_raw_count, new_raw_count;
309 
310 	do {
311 		prev_raw_count = local64_read(&hwc->prev_count);
312 		new_raw_count = mmdc_pmu_read_counter(pmu_mmdc,
313 						      event->attr.config);
314 	} while (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
315 		new_raw_count) != prev_raw_count);
316 
317 	delta = (new_raw_count - prev_raw_count) & 0xFFFFFFFF;
318 
319 	local64_add(delta, &event->count);
320 }
321 
322 static void mmdc_pmu_event_start(struct perf_event *event, int flags)
323 {
324 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
325 	struct hw_perf_event *hwc = &event->hw;
326 	void __iomem *mmdc_base, *reg;
327 	u32 val;
328 
329 	mmdc_base = pmu_mmdc->mmdc_base;
330 	reg = mmdc_base + MMDC_MADPCR0;
331 
332 	/*
333 	 * hrtimer is required because mmdc does not provide an interrupt so
334 	 * polling is necessary
335 	 */
336 	hrtimer_start(&pmu_mmdc->hrtimer, mmdc_pmu_timer_period(),
337 			HRTIMER_MODE_REL_PINNED);
338 
339 	local64_set(&hwc->prev_count, 0);
340 
341 	writel(DBG_RST, reg);
342 
343 	/*
344 	 * Write the AXI id parameter to MADPCR1.
345 	 */
346 	val = event->attr.config1;
347 	reg = mmdc_base + MMDC_MADPCR1;
348 	writel(val, reg);
349 
350 	reg = mmdc_base + MMDC_MADPCR0;
351 	val = DBG_EN;
352 	if (pmu_mmdc->devtype_data->flags & MMDC_FLAG_PROFILE_SEL)
353 		val |= PROFILE_SEL;
354 
355 	writel(val, reg);
356 }
357 
358 static int mmdc_pmu_event_add(struct perf_event *event, int flags)
359 {
360 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
361 	struct hw_perf_event *hwc = &event->hw;
362 
363 	int cfg = event->attr.config;
364 
365 	if (flags & PERF_EF_START)
366 		mmdc_pmu_event_start(event, flags);
367 
368 	if (pmu_mmdc->mmdc_events[cfg] != NULL)
369 		return -EAGAIN;
370 
371 	pmu_mmdc->mmdc_events[cfg] = event;
372 	pmu_mmdc->active_events++;
373 
374 	local64_set(&hwc->prev_count, mmdc_pmu_read_counter(pmu_mmdc, cfg));
375 
376 	return 0;
377 }
378 
379 static void mmdc_pmu_event_stop(struct perf_event *event, int flags)
380 {
381 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
382 	void __iomem *mmdc_base, *reg;
383 
384 	mmdc_base = pmu_mmdc->mmdc_base;
385 	reg = mmdc_base + MMDC_MADPCR0;
386 
387 	writel(PRF_FRZ, reg);
388 
389 	reg = mmdc_base + MMDC_MADPCR1;
390 	writel(MMDC_PRF_AXI_ID_CLEAR, reg);
391 
392 	mmdc_pmu_event_update(event);
393 }
394 
395 static void mmdc_pmu_event_del(struct perf_event *event, int flags)
396 {
397 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
398 	int cfg = event->attr.config;
399 
400 	pmu_mmdc->mmdc_events[cfg] = NULL;
401 	pmu_mmdc->active_events--;
402 
403 	if (pmu_mmdc->active_events == 0)
404 		hrtimer_cancel(&pmu_mmdc->hrtimer);
405 
406 	mmdc_pmu_event_stop(event, PERF_EF_UPDATE);
407 }
408 
409 static void mmdc_pmu_overflow_handler(struct mmdc_pmu *pmu_mmdc)
410 {
411 	int i;
412 
413 	for (i = 0; i < MMDC_NUM_COUNTERS; i++) {
414 		struct perf_event *event = pmu_mmdc->mmdc_events[i];
415 
416 		if (event)
417 			mmdc_pmu_event_update(event);
418 	}
419 }
420 
421 static enum hrtimer_restart mmdc_pmu_timer_handler(struct hrtimer *hrtimer)
422 {
423 	struct mmdc_pmu *pmu_mmdc = container_of(hrtimer, struct mmdc_pmu,
424 			hrtimer);
425 
426 	mmdc_pmu_overflow_handler(pmu_mmdc);
427 	hrtimer_forward_now(hrtimer, mmdc_pmu_timer_period());
428 
429 	return HRTIMER_RESTART;
430 }
431 
432 static int mmdc_pmu_init(struct mmdc_pmu *pmu_mmdc,
433 		void __iomem *mmdc_base, struct device *dev)
434 {
435 	int mmdc_num;
436 
437 	*pmu_mmdc = (struct mmdc_pmu) {
438 		.pmu = (struct pmu) {
439 			.task_ctx_nr    = perf_invalid_context,
440 			.attr_groups    = attr_groups,
441 			.event_init     = mmdc_pmu_event_init,
442 			.add            = mmdc_pmu_event_add,
443 			.del            = mmdc_pmu_event_del,
444 			.start          = mmdc_pmu_event_start,
445 			.stop           = mmdc_pmu_event_stop,
446 			.read           = mmdc_pmu_event_update,
447 			.capabilities	= PERF_PMU_CAP_NO_EXCLUDE,
448 		},
449 		.mmdc_base = mmdc_base,
450 		.dev = dev,
451 		.active_events = 0,
452 	};
453 
454 	mmdc_num = ida_simple_get(&mmdc_ida, 0, 0, GFP_KERNEL);
455 
456 	return mmdc_num;
457 }
458 
459 static int imx_mmdc_remove(struct platform_device *pdev)
460 {
461 	struct mmdc_pmu *pmu_mmdc = platform_get_drvdata(pdev);
462 
463 	cpuhp_state_remove_instance_nocalls(cpuhp_mmdc_state, &pmu_mmdc->node);
464 	perf_pmu_unregister(&pmu_mmdc->pmu);
465 	kfree(pmu_mmdc);
466 	return 0;
467 }
468 
469 static int imx_mmdc_perf_init(struct platform_device *pdev, void __iomem *mmdc_base)
470 {
471 	struct mmdc_pmu *pmu_mmdc;
472 	char *name;
473 	int mmdc_num;
474 	int ret;
475 	const struct of_device_id *of_id =
476 		of_match_device(imx_mmdc_dt_ids, &pdev->dev);
477 
478 	pmu_mmdc = kzalloc(sizeof(*pmu_mmdc), GFP_KERNEL);
479 	if (!pmu_mmdc) {
480 		pr_err("failed to allocate PMU device!\n");
481 		return -ENOMEM;
482 	}
483 
484 	/* The first instance registers the hotplug state */
485 	if (!cpuhp_mmdc_state) {
486 		ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN,
487 					      "perf/arm/mmdc:online", NULL,
488 					      mmdc_pmu_offline_cpu);
489 		if (ret < 0) {
490 			pr_err("cpuhp_setup_state_multi failed\n");
491 			goto pmu_free;
492 		}
493 		cpuhp_mmdc_state = ret;
494 	}
495 
496 	mmdc_num = mmdc_pmu_init(pmu_mmdc, mmdc_base, &pdev->dev);
497 	if (mmdc_num == 0)
498 		name = "mmdc";
499 	else
500 		name = devm_kasprintf(&pdev->dev,
501 				GFP_KERNEL, "mmdc%d", mmdc_num);
502 
503 	pmu_mmdc->devtype_data = (struct fsl_mmdc_devtype_data *)of_id->data;
504 
505 	hrtimer_init(&pmu_mmdc->hrtimer, CLOCK_MONOTONIC,
506 			HRTIMER_MODE_REL);
507 	pmu_mmdc->hrtimer.function = mmdc_pmu_timer_handler;
508 
509 	cpumask_set_cpu(raw_smp_processor_id(), &pmu_mmdc->cpu);
510 
511 	/* Register the pmu instance for cpu hotplug */
512 	cpuhp_state_add_instance_nocalls(cpuhp_mmdc_state, &pmu_mmdc->node);
513 
514 	ret = perf_pmu_register(&(pmu_mmdc->pmu), name, -1);
515 	if (ret)
516 		goto pmu_register_err;
517 
518 	platform_set_drvdata(pdev, pmu_mmdc);
519 	return 0;
520 
521 pmu_register_err:
522 	pr_warn("MMDC Perf PMU failed (%d), disabled\n", ret);
523 	cpuhp_state_remove_instance_nocalls(cpuhp_mmdc_state, &pmu_mmdc->node);
524 	hrtimer_cancel(&pmu_mmdc->hrtimer);
525 pmu_free:
526 	kfree(pmu_mmdc);
527 	return ret;
528 }
529 
530 #else
531 #define imx_mmdc_remove NULL
532 #define imx_mmdc_perf_init(pdev, mmdc_base) 0
533 #endif
534 
535 static int imx_mmdc_probe(struct platform_device *pdev)
536 {
537 	struct device_node *np = pdev->dev.of_node;
538 	void __iomem *mmdc_base, *reg;
539 	struct clk *mmdc_ipg_clk;
540 	u32 val;
541 	int err;
542 
543 	/* the ipg clock is optional */
544 	mmdc_ipg_clk = devm_clk_get(&pdev->dev, NULL);
545 	if (IS_ERR(mmdc_ipg_clk))
546 		mmdc_ipg_clk = NULL;
547 
548 	err = clk_prepare_enable(mmdc_ipg_clk);
549 	if (err) {
550 		dev_err(&pdev->dev, "Unable to enable mmdc ipg clock.\n");
551 		return err;
552 	}
553 
554 	mmdc_base = of_iomap(np, 0);
555 	WARN_ON(!mmdc_base);
556 
557 	reg = mmdc_base + MMDC_MDMISC;
558 	/* Get ddr type */
559 	val = readl_relaxed(reg);
560 	ddr_type = (val & BM_MMDC_MDMISC_DDR_TYPE) >>
561 		 BP_MMDC_MDMISC_DDR_TYPE;
562 
563 	reg = mmdc_base + MMDC_MAPSR;
564 
565 	/* Enable automatic power saving */
566 	val = readl_relaxed(reg);
567 	val &= ~(1 << BP_MMDC_MAPSR_PSD);
568 	writel_relaxed(val, reg);
569 
570 	return imx_mmdc_perf_init(pdev, mmdc_base);
571 }
572 
573 int imx_mmdc_get_ddr_type(void)
574 {
575 	return ddr_type;
576 }
577 
578 static struct platform_driver imx_mmdc_driver = {
579 	.driver		= {
580 		.name	= "imx-mmdc",
581 		.of_match_table = imx_mmdc_dt_ids,
582 	},
583 	.probe		= imx_mmdc_probe,
584 	.remove		= imx_mmdc_remove,
585 };
586 
587 static int __init imx_mmdc_init(void)
588 {
589 	return platform_driver_register(&imx_mmdc_driver);
590 }
591 postcore_initcall(imx_mmdc_init);
592