xref: /openbmc/linux/arch/arm/mach-imx/mmdc.c (revision ffcdf473) 
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 	int id;
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 	struct clk *mmdc_ipg_clk;
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 PMU_FORMAT_ATTR(axi_id, "config1:0-63");
165 
166 static struct attribute *mmdc_pmu_format_attrs[] = {
167 	&format_attr_event.attr,
168 	&format_attr_axi_id.attr,
169 	NULL,
170 };
171 
172 static struct attribute_group mmdc_pmu_format_attr_group = {
173 	.name = "format",
174 	.attrs = mmdc_pmu_format_attrs,
175 };
176 
177 static const struct attribute_group *attr_groups[] = {
178 	&mmdc_pmu_events_attr_group,
179 	&mmdc_pmu_format_attr_group,
180 	&mmdc_pmu_cpumask_attr_group,
181 	NULL,
182 };
183 
184 static u32 mmdc_pmu_read_counter(struct mmdc_pmu *pmu_mmdc, int cfg)
185 {
186 	void __iomem *mmdc_base, *reg;
187 
188 	mmdc_base = pmu_mmdc->mmdc_base;
189 
190 	switch (cfg) {
191 	case TOTAL_CYCLES:
192 		reg = mmdc_base + MMDC_MADPSR0;
193 		break;
194 	case BUSY_CYCLES:
195 		reg = mmdc_base + MMDC_MADPSR1;
196 		break;
197 	case READ_ACCESSES:
198 		reg = mmdc_base + MMDC_MADPSR2;
199 		break;
200 	case WRITE_ACCESSES:
201 		reg = mmdc_base + MMDC_MADPSR3;
202 		break;
203 	case READ_BYTES:
204 		reg = mmdc_base + MMDC_MADPSR4;
205 		break;
206 	case WRITE_BYTES:
207 		reg = mmdc_base + MMDC_MADPSR5;
208 		break;
209 	default:
210 		return WARN_ONCE(1,
211 			"invalid configuration %d for mmdc counter", cfg);
212 	}
213 	return readl(reg);
214 }
215 
216 static int mmdc_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
217 {
218 	struct mmdc_pmu *pmu_mmdc = hlist_entry_safe(node, struct mmdc_pmu, node);
219 	int target;
220 
221 	if (!cpumask_test_and_clear_cpu(cpu, &pmu_mmdc->cpu))
222 		return 0;
223 
224 	target = cpumask_any_but(cpu_online_mask, cpu);
225 	if (target >= nr_cpu_ids)
226 		return 0;
227 
228 	perf_pmu_migrate_context(&pmu_mmdc->pmu, cpu, target);
229 	cpumask_set_cpu(target, &pmu_mmdc->cpu);
230 
231 	return 0;
232 }
233 
234 static bool mmdc_pmu_group_event_is_valid(struct perf_event *event,
235 					  struct pmu *pmu,
236 					  unsigned long *used_counters)
237 {
238 	int cfg = event->attr.config;
239 
240 	if (is_software_event(event))
241 		return true;
242 
243 	if (event->pmu != pmu)
244 		return false;
245 
246 	return !test_and_set_bit(cfg, used_counters);
247 }
248 
249 /*
250  * Each event has a single fixed-purpose counter, so we can only have a
251  * single active event for each at any point in time. Here we just check
252  * for duplicates, and rely on mmdc_pmu_event_init to verify that the HW
253  * event numbers are valid.
254  */
255 static bool mmdc_pmu_group_is_valid(struct perf_event *event)
256 {
257 	struct pmu *pmu = event->pmu;
258 	struct perf_event *leader = event->group_leader;
259 	struct perf_event *sibling;
260 	unsigned long counter_mask = 0;
261 
262 	set_bit(leader->attr.config, &counter_mask);
263 
264 	if (event != leader) {
265 		if (!mmdc_pmu_group_event_is_valid(event, pmu, &counter_mask))
266 			return false;
267 	}
268 
269 	for_each_sibling_event(sibling, leader) {
270 		if (!mmdc_pmu_group_event_is_valid(sibling, pmu, &counter_mask))
271 			return false;
272 	}
273 
274 	return true;
275 }
276 
277 static int mmdc_pmu_event_init(struct perf_event *event)
278 {
279 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
280 	int cfg = event->attr.config;
281 
282 	if (event->attr.type != event->pmu->type)
283 		return -ENOENT;
284 
285 	if (is_sampling_event(event) || event->attach_state & PERF_ATTACH_TASK)
286 		return -EOPNOTSUPP;
287 
288 	if (event->cpu < 0) {
289 		dev_warn(pmu_mmdc->dev, "Can't provide per-task data!\n");
290 		return -EOPNOTSUPP;
291 	}
292 
293 	if (event->attr.sample_period)
294 		return -EINVAL;
295 
296 	if (cfg < 0 || cfg >= MMDC_NUM_COUNTERS)
297 		return -EINVAL;
298 
299 	if (!mmdc_pmu_group_is_valid(event))
300 		return -EINVAL;
301 
302 	event->cpu = cpumask_first(&pmu_mmdc->cpu);
303 	return 0;
304 }
305 
306 static void mmdc_pmu_event_update(struct perf_event *event)
307 {
308 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
309 	struct hw_perf_event *hwc = &event->hw;
310 	u64 delta, prev_raw_count, new_raw_count;
311 
312 	do {
313 		prev_raw_count = local64_read(&hwc->prev_count);
314 		new_raw_count = mmdc_pmu_read_counter(pmu_mmdc,
315 						      event->attr.config);
316 	} while (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
317 		new_raw_count) != prev_raw_count);
318 
319 	delta = (new_raw_count - prev_raw_count) & 0xFFFFFFFF;
320 
321 	local64_add(delta, &event->count);
322 }
323 
324 static void mmdc_pmu_event_start(struct perf_event *event, int flags)
325 {
326 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
327 	struct hw_perf_event *hwc = &event->hw;
328 	void __iomem *mmdc_base, *reg;
329 	u32 val;
330 
331 	mmdc_base = pmu_mmdc->mmdc_base;
332 	reg = mmdc_base + MMDC_MADPCR0;
333 
334 	/*
335 	 * hrtimer is required because mmdc does not provide an interrupt so
336 	 * polling is necessary
337 	 */
338 	hrtimer_start(&pmu_mmdc->hrtimer, mmdc_pmu_timer_period(),
339 			HRTIMER_MODE_REL_PINNED);
340 
341 	local64_set(&hwc->prev_count, 0);
342 
343 	writel(DBG_RST, reg);
344 
345 	/*
346 	 * Write the AXI id parameter to MADPCR1.
347 	 */
348 	val = event->attr.config1;
349 	reg = mmdc_base + MMDC_MADPCR1;
350 	writel(val, reg);
351 
352 	reg = mmdc_base + MMDC_MADPCR0;
353 	val = DBG_EN;
354 	if (pmu_mmdc->devtype_data->flags & MMDC_FLAG_PROFILE_SEL)
355 		val |= PROFILE_SEL;
356 
357 	writel(val, reg);
358 }
359 
360 static int mmdc_pmu_event_add(struct perf_event *event, int flags)
361 {
362 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
363 	struct hw_perf_event *hwc = &event->hw;
364 
365 	int cfg = event->attr.config;
366 
367 	if (flags & PERF_EF_START)
368 		mmdc_pmu_event_start(event, flags);
369 
370 	if (pmu_mmdc->mmdc_events[cfg] != NULL)
371 		return -EAGAIN;
372 
373 	pmu_mmdc->mmdc_events[cfg] = event;
374 	pmu_mmdc->active_events++;
375 
376 	local64_set(&hwc->prev_count, mmdc_pmu_read_counter(pmu_mmdc, cfg));
377 
378 	return 0;
379 }
380 
381 static void mmdc_pmu_event_stop(struct perf_event *event, int flags)
382 {
383 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
384 	void __iomem *mmdc_base, *reg;
385 
386 	mmdc_base = pmu_mmdc->mmdc_base;
387 	reg = mmdc_base + MMDC_MADPCR0;
388 
389 	writel(PRF_FRZ, reg);
390 
391 	reg = mmdc_base + MMDC_MADPCR1;
392 	writel(MMDC_PRF_AXI_ID_CLEAR, reg);
393 
394 	mmdc_pmu_event_update(event);
395 }
396 
397 static void mmdc_pmu_event_del(struct perf_event *event, int flags)
398 {
399 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
400 	int cfg = event->attr.config;
401 
402 	pmu_mmdc->mmdc_events[cfg] = NULL;
403 	pmu_mmdc->active_events--;
404 
405 	if (pmu_mmdc->active_events == 0)
406 		hrtimer_cancel(&pmu_mmdc->hrtimer);
407 
408 	mmdc_pmu_event_stop(event, PERF_EF_UPDATE);
409 }
410 
411 static void mmdc_pmu_overflow_handler(struct mmdc_pmu *pmu_mmdc)
412 {
413 	int i;
414 
415 	for (i = 0; i < MMDC_NUM_COUNTERS; i++) {
416 		struct perf_event *event = pmu_mmdc->mmdc_events[i];
417 
418 		if (event)
419 			mmdc_pmu_event_update(event);
420 	}
421 }
422 
423 static enum hrtimer_restart mmdc_pmu_timer_handler(struct hrtimer *hrtimer)
424 {
425 	struct mmdc_pmu *pmu_mmdc = container_of(hrtimer, struct mmdc_pmu,
426 			hrtimer);
427 
428 	mmdc_pmu_overflow_handler(pmu_mmdc);
429 	hrtimer_forward_now(hrtimer, mmdc_pmu_timer_period());
430 
431 	return HRTIMER_RESTART;
432 }
433 
434 static int mmdc_pmu_init(struct mmdc_pmu *pmu_mmdc,
435 		void __iomem *mmdc_base, struct device *dev)
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 	pmu_mmdc->id = ida_simple_get(&mmdc_ida, 0, 0, GFP_KERNEL);
455 
456 	return pmu_mmdc->id;
457 }
458 
459 static void imx_mmdc_remove(struct platform_device *pdev)
460 {
461 	struct mmdc_pmu *pmu_mmdc = platform_get_drvdata(pdev);
462 
463 	ida_simple_remove(&mmdc_ida, pmu_mmdc->id);
464 	cpuhp_state_remove_instance_nocalls(cpuhp_mmdc_state, &pmu_mmdc->node);
465 	perf_pmu_unregister(&pmu_mmdc->pmu);
466 	iounmap(pmu_mmdc->mmdc_base);
467 	clk_disable_unprepare(pmu_mmdc->mmdc_ipg_clk);
468 	kfree(pmu_mmdc);
469 }
470 
471 static int imx_mmdc_perf_init(struct platform_device *pdev, void __iomem *mmdc_base,
472 			      struct clk *mmdc_ipg_clk)
473 {
474 	struct mmdc_pmu *pmu_mmdc;
475 	char *name;
476 	int ret;
477 	const struct of_device_id *of_id =
478 		of_match_device(imx_mmdc_dt_ids, &pdev->dev);
479 
480 	pmu_mmdc = kzalloc(sizeof(*pmu_mmdc), GFP_KERNEL);
481 	if (!pmu_mmdc) {
482 		pr_err("failed to allocate PMU device!\n");
483 		return -ENOMEM;
484 	}
485 
486 	/* The first instance registers the hotplug state */
487 	if (!cpuhp_mmdc_state) {
488 		ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN,
489 					      "perf/arm/mmdc:online", NULL,
490 					      mmdc_pmu_offline_cpu);
491 		if (ret < 0) {
492 			pr_err("cpuhp_setup_state_multi failed\n");
493 			goto pmu_free;
494 		}
495 		cpuhp_mmdc_state = ret;
496 	}
497 
498 	ret = mmdc_pmu_init(pmu_mmdc, mmdc_base, &pdev->dev);
499 	if (ret < 0)
500 		goto  pmu_free;
501 
502 	name = devm_kasprintf(&pdev->dev,
503 				GFP_KERNEL, "mmdc%d", ret);
504 
505 	pmu_mmdc->mmdc_ipg_clk = mmdc_ipg_clk;
506 	pmu_mmdc->devtype_data = (struct fsl_mmdc_devtype_data *)of_id->data;
507 
508 	hrtimer_init(&pmu_mmdc->hrtimer, CLOCK_MONOTONIC,
509 			HRTIMER_MODE_REL);
510 	pmu_mmdc->hrtimer.function = mmdc_pmu_timer_handler;
511 
512 	cpumask_set_cpu(raw_smp_processor_id(), &pmu_mmdc->cpu);
513 
514 	/* Register the pmu instance for cpu hotplug */
515 	cpuhp_state_add_instance_nocalls(cpuhp_mmdc_state, &pmu_mmdc->node);
516 
517 	ret = perf_pmu_register(&(pmu_mmdc->pmu), name, -1);
518 	if (ret)
519 		goto pmu_register_err;
520 
521 	platform_set_drvdata(pdev, pmu_mmdc);
522 	return 0;
523 
524 pmu_register_err:
525 	pr_warn("MMDC Perf PMU failed (%d), disabled\n", ret);
526 	ida_simple_remove(&mmdc_ida, pmu_mmdc->id);
527 	cpuhp_state_remove_instance_nocalls(cpuhp_mmdc_state, &pmu_mmdc->node);
528 	hrtimer_cancel(&pmu_mmdc->hrtimer);
529 pmu_free:
530 	kfree(pmu_mmdc);
531 	return ret;
532 }
533 
534 #else
535 #define imx_mmdc_remove NULL
536 #define imx_mmdc_perf_init(pdev, mmdc_base, mmdc_ipg_clk) 0
537 #endif
538 
539 static int imx_mmdc_probe(struct platform_device *pdev)
540 {
541 	struct device_node *np = pdev->dev.of_node;
542 	void __iomem *mmdc_base, *reg;
543 	struct clk *mmdc_ipg_clk;
544 	u32 val;
545 	int err;
546 
547 	/* the ipg clock is optional */
548 	mmdc_ipg_clk = devm_clk_get(&pdev->dev, NULL);
549 	if (IS_ERR(mmdc_ipg_clk))
550 		mmdc_ipg_clk = NULL;
551 
552 	err = clk_prepare_enable(mmdc_ipg_clk);
553 	if (err) {
554 		dev_err(&pdev->dev, "Unable to enable mmdc ipg clock.\n");
555 		return err;
556 	}
557 
558 	mmdc_base = of_iomap(np, 0);
559 	WARN_ON(!mmdc_base);
560 
561 	reg = mmdc_base + MMDC_MDMISC;
562 	/* Get ddr type */
563 	val = readl_relaxed(reg);
564 	ddr_type = (val & BM_MMDC_MDMISC_DDR_TYPE) >>
565 		 BP_MMDC_MDMISC_DDR_TYPE;
566 
567 	reg = mmdc_base + MMDC_MAPSR;
568 
569 	/* Enable automatic power saving */
570 	val = readl_relaxed(reg);
571 	val &= ~(1 << BP_MMDC_MAPSR_PSD);
572 	writel_relaxed(val, reg);
573 
574 	err = imx_mmdc_perf_init(pdev, mmdc_base, mmdc_ipg_clk);
575 	if (err) {
576 		iounmap(mmdc_base);
577 		clk_disable_unprepare(mmdc_ipg_clk);
578 	}
579 
580 	return err;
581 }
582 
583 int imx_mmdc_get_ddr_type(void)
584 {
585 	return ddr_type;
586 }
587 
588 static struct platform_driver imx_mmdc_driver = {
589 	.driver		= {
590 		.name	= "imx-mmdc",
591 		.of_match_table = imx_mmdc_dt_ids,
592 	},
593 	.probe		= imx_mmdc_probe,
594 	.remove_new	= imx_mmdc_remove,
595 };
596 
597 static int __init imx_mmdc_init(void)
598 {
599 	return platform_driver_register(&imx_mmdc_driver);
600 }
601 postcore_initcall(imx_mmdc_init);
602