xref: /openbmc/linux/arch/arm/mach-imx/mmdc.c (revision 2cf1c348)
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 	struct clk *mmdc_ipg_clk;
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 PMU_FORMAT_ATTR(axi_id, "config1:0-63");
164 
165 static struct attribute *mmdc_pmu_format_attrs[] = {
166 	&format_attr_event.attr,
167 	&format_attr_axi_id.attr,
168 	NULL,
169 };
170 
171 static struct attribute_group mmdc_pmu_format_attr_group = {
172 	.name = "format",
173 	.attrs = mmdc_pmu_format_attrs,
174 };
175 
176 static const struct attribute_group *attr_groups[] = {
177 	&mmdc_pmu_events_attr_group,
178 	&mmdc_pmu_format_attr_group,
179 	&mmdc_pmu_cpumask_attr_group,
180 	NULL,
181 };
182 
183 static u32 mmdc_pmu_read_counter(struct mmdc_pmu *pmu_mmdc, int cfg)
184 {
185 	void __iomem *mmdc_base, *reg;
186 
187 	mmdc_base = pmu_mmdc->mmdc_base;
188 
189 	switch (cfg) {
190 	case TOTAL_CYCLES:
191 		reg = mmdc_base + MMDC_MADPSR0;
192 		break;
193 	case BUSY_CYCLES:
194 		reg = mmdc_base + MMDC_MADPSR1;
195 		break;
196 	case READ_ACCESSES:
197 		reg = mmdc_base + MMDC_MADPSR2;
198 		break;
199 	case WRITE_ACCESSES:
200 		reg = mmdc_base + MMDC_MADPSR3;
201 		break;
202 	case READ_BYTES:
203 		reg = mmdc_base + MMDC_MADPSR4;
204 		break;
205 	case WRITE_BYTES:
206 		reg = mmdc_base + MMDC_MADPSR5;
207 		break;
208 	default:
209 		return WARN_ONCE(1,
210 			"invalid configuration %d for mmdc counter", cfg);
211 	}
212 	return readl(reg);
213 }
214 
215 static int mmdc_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
216 {
217 	struct mmdc_pmu *pmu_mmdc = hlist_entry_safe(node, struct mmdc_pmu, node);
218 	int target;
219 
220 	if (!cpumask_test_and_clear_cpu(cpu, &pmu_mmdc->cpu))
221 		return 0;
222 
223 	target = cpumask_any_but(cpu_online_mask, cpu);
224 	if (target >= nr_cpu_ids)
225 		return 0;
226 
227 	perf_pmu_migrate_context(&pmu_mmdc->pmu, cpu, target);
228 	cpumask_set_cpu(target, &pmu_mmdc->cpu);
229 
230 	return 0;
231 }
232 
233 static bool mmdc_pmu_group_event_is_valid(struct perf_event *event,
234 					  struct pmu *pmu,
235 					  unsigned long *used_counters)
236 {
237 	int cfg = event->attr.config;
238 
239 	if (is_software_event(event))
240 		return true;
241 
242 	if (event->pmu != pmu)
243 		return false;
244 
245 	return !test_and_set_bit(cfg, used_counters);
246 }
247 
248 /*
249  * Each event has a single fixed-purpose counter, so we can only have a
250  * single active event for each at any point in time. Here we just check
251  * for duplicates, and rely on mmdc_pmu_event_init to verify that the HW
252  * event numbers are valid.
253  */
254 static bool mmdc_pmu_group_is_valid(struct perf_event *event)
255 {
256 	struct pmu *pmu = event->pmu;
257 	struct perf_event *leader = event->group_leader;
258 	struct perf_event *sibling;
259 	unsigned long counter_mask = 0;
260 
261 	set_bit(leader->attr.config, &counter_mask);
262 
263 	if (event != leader) {
264 		if (!mmdc_pmu_group_event_is_valid(event, pmu, &counter_mask))
265 			return false;
266 	}
267 
268 	for_each_sibling_event(sibling, leader) {
269 		if (!mmdc_pmu_group_event_is_valid(sibling, pmu, &counter_mask))
270 			return false;
271 	}
272 
273 	return true;
274 }
275 
276 static int mmdc_pmu_event_init(struct perf_event *event)
277 {
278 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
279 	int cfg = event->attr.config;
280 
281 	if (event->attr.type != event->pmu->type)
282 		return -ENOENT;
283 
284 	if (is_sampling_event(event) || event->attach_state & PERF_ATTACH_TASK)
285 		return -EOPNOTSUPP;
286 
287 	if (event->cpu < 0) {
288 		dev_warn(pmu_mmdc->dev, "Can't provide per-task data!\n");
289 		return -EOPNOTSUPP;
290 	}
291 
292 	if (event->attr.sample_period)
293 		return -EINVAL;
294 
295 	if (cfg < 0 || cfg >= MMDC_NUM_COUNTERS)
296 		return -EINVAL;
297 
298 	if (!mmdc_pmu_group_is_valid(event))
299 		return -EINVAL;
300 
301 	event->cpu = cpumask_first(&pmu_mmdc->cpu);
302 	return 0;
303 }
304 
305 static void mmdc_pmu_event_update(struct perf_event *event)
306 {
307 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
308 	struct hw_perf_event *hwc = &event->hw;
309 	u64 delta, prev_raw_count, new_raw_count;
310 
311 	do {
312 		prev_raw_count = local64_read(&hwc->prev_count);
313 		new_raw_count = mmdc_pmu_read_counter(pmu_mmdc,
314 						      event->attr.config);
315 	} while (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
316 		new_raw_count) != prev_raw_count);
317 
318 	delta = (new_raw_count - prev_raw_count) & 0xFFFFFFFF;
319 
320 	local64_add(delta, &event->count);
321 }
322 
323 static void mmdc_pmu_event_start(struct perf_event *event, int flags)
324 {
325 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
326 	struct hw_perf_event *hwc = &event->hw;
327 	void __iomem *mmdc_base, *reg;
328 	u32 val;
329 
330 	mmdc_base = pmu_mmdc->mmdc_base;
331 	reg = mmdc_base + MMDC_MADPCR0;
332 
333 	/*
334 	 * hrtimer is required because mmdc does not provide an interrupt so
335 	 * polling is necessary
336 	 */
337 	hrtimer_start(&pmu_mmdc->hrtimer, mmdc_pmu_timer_period(),
338 			HRTIMER_MODE_REL_PINNED);
339 
340 	local64_set(&hwc->prev_count, 0);
341 
342 	writel(DBG_RST, reg);
343 
344 	/*
345 	 * Write the AXI id parameter to MADPCR1.
346 	 */
347 	val = event->attr.config1;
348 	reg = mmdc_base + MMDC_MADPCR1;
349 	writel(val, reg);
350 
351 	reg = mmdc_base + MMDC_MADPCR0;
352 	val = DBG_EN;
353 	if (pmu_mmdc->devtype_data->flags & MMDC_FLAG_PROFILE_SEL)
354 		val |= PROFILE_SEL;
355 
356 	writel(val, reg);
357 }
358 
359 static int mmdc_pmu_event_add(struct perf_event *event, int flags)
360 {
361 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
362 	struct hw_perf_event *hwc = &event->hw;
363 
364 	int cfg = event->attr.config;
365 
366 	if (flags & PERF_EF_START)
367 		mmdc_pmu_event_start(event, flags);
368 
369 	if (pmu_mmdc->mmdc_events[cfg] != NULL)
370 		return -EAGAIN;
371 
372 	pmu_mmdc->mmdc_events[cfg] = event;
373 	pmu_mmdc->active_events++;
374 
375 	local64_set(&hwc->prev_count, mmdc_pmu_read_counter(pmu_mmdc, cfg));
376 
377 	return 0;
378 }
379 
380 static void mmdc_pmu_event_stop(struct perf_event *event, int flags)
381 {
382 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
383 	void __iomem *mmdc_base, *reg;
384 
385 	mmdc_base = pmu_mmdc->mmdc_base;
386 	reg = mmdc_base + MMDC_MADPCR0;
387 
388 	writel(PRF_FRZ, reg);
389 
390 	reg = mmdc_base + MMDC_MADPCR1;
391 	writel(MMDC_PRF_AXI_ID_CLEAR, reg);
392 
393 	mmdc_pmu_event_update(event);
394 }
395 
396 static void mmdc_pmu_event_del(struct perf_event *event, int flags)
397 {
398 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
399 	int cfg = event->attr.config;
400 
401 	pmu_mmdc->mmdc_events[cfg] = NULL;
402 	pmu_mmdc->active_events--;
403 
404 	if (pmu_mmdc->active_events == 0)
405 		hrtimer_cancel(&pmu_mmdc->hrtimer);
406 
407 	mmdc_pmu_event_stop(event, PERF_EF_UPDATE);
408 }
409 
410 static void mmdc_pmu_overflow_handler(struct mmdc_pmu *pmu_mmdc)
411 {
412 	int i;
413 
414 	for (i = 0; i < MMDC_NUM_COUNTERS; i++) {
415 		struct perf_event *event = pmu_mmdc->mmdc_events[i];
416 
417 		if (event)
418 			mmdc_pmu_event_update(event);
419 	}
420 }
421 
422 static enum hrtimer_restart mmdc_pmu_timer_handler(struct hrtimer *hrtimer)
423 {
424 	struct mmdc_pmu *pmu_mmdc = container_of(hrtimer, struct mmdc_pmu,
425 			hrtimer);
426 
427 	mmdc_pmu_overflow_handler(pmu_mmdc);
428 	hrtimer_forward_now(hrtimer, mmdc_pmu_timer_period());
429 
430 	return HRTIMER_RESTART;
431 }
432 
433 static int mmdc_pmu_init(struct mmdc_pmu *pmu_mmdc,
434 		void __iomem *mmdc_base, struct device *dev)
435 {
436 	int mmdc_num;
437 
438 	*pmu_mmdc = (struct mmdc_pmu) {
439 		.pmu = (struct pmu) {
440 			.task_ctx_nr    = perf_invalid_context,
441 			.attr_groups    = attr_groups,
442 			.event_init     = mmdc_pmu_event_init,
443 			.add            = mmdc_pmu_event_add,
444 			.del            = mmdc_pmu_event_del,
445 			.start          = mmdc_pmu_event_start,
446 			.stop           = mmdc_pmu_event_stop,
447 			.read           = mmdc_pmu_event_update,
448 			.capabilities	= PERF_PMU_CAP_NO_EXCLUDE,
449 		},
450 		.mmdc_base = mmdc_base,
451 		.dev = dev,
452 		.active_events = 0,
453 	};
454 
455 	mmdc_num = ida_simple_get(&mmdc_ida, 0, 0, GFP_KERNEL);
456 
457 	return mmdc_num;
458 }
459 
460 static int imx_mmdc_remove(struct platform_device *pdev)
461 {
462 	struct mmdc_pmu *pmu_mmdc = platform_get_drvdata(pdev);
463 
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 	return 0;
470 }
471 
472 static int imx_mmdc_perf_init(struct platform_device *pdev, void __iomem *mmdc_base,
473 			      struct clk *mmdc_ipg_clk)
474 {
475 	struct mmdc_pmu *pmu_mmdc;
476 	char *name;
477 	int mmdc_num;
478 	int ret;
479 	const struct of_device_id *of_id =
480 		of_match_device(imx_mmdc_dt_ids, &pdev->dev);
481 
482 	pmu_mmdc = kzalloc(sizeof(*pmu_mmdc), GFP_KERNEL);
483 	if (!pmu_mmdc) {
484 		pr_err("failed to allocate PMU device!\n");
485 		return -ENOMEM;
486 	}
487 
488 	/* The first instance registers the hotplug state */
489 	if (!cpuhp_mmdc_state) {
490 		ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN,
491 					      "perf/arm/mmdc:online", NULL,
492 					      mmdc_pmu_offline_cpu);
493 		if (ret < 0) {
494 			pr_err("cpuhp_setup_state_multi failed\n");
495 			goto pmu_free;
496 		}
497 		cpuhp_mmdc_state = ret;
498 	}
499 
500 	mmdc_num = mmdc_pmu_init(pmu_mmdc, mmdc_base, &pdev->dev);
501 	pmu_mmdc->mmdc_ipg_clk = mmdc_ipg_clk;
502 	if (mmdc_num == 0)
503 		name = "mmdc";
504 	else
505 		name = devm_kasprintf(&pdev->dev,
506 				GFP_KERNEL, "mmdc%d", mmdc_num);
507 
508 	pmu_mmdc->devtype_data = (struct fsl_mmdc_devtype_data *)of_id->data;
509 
510 	hrtimer_init(&pmu_mmdc->hrtimer, CLOCK_MONOTONIC,
511 			HRTIMER_MODE_REL);
512 	pmu_mmdc->hrtimer.function = mmdc_pmu_timer_handler;
513 
514 	cpumask_set_cpu(raw_smp_processor_id(), &pmu_mmdc->cpu);
515 
516 	/* Register the pmu instance for cpu hotplug */
517 	cpuhp_state_add_instance_nocalls(cpuhp_mmdc_state, &pmu_mmdc->node);
518 
519 	ret = perf_pmu_register(&(pmu_mmdc->pmu), name, -1);
520 	if (ret)
521 		goto pmu_register_err;
522 
523 	platform_set_drvdata(pdev, pmu_mmdc);
524 	return 0;
525 
526 pmu_register_err:
527 	pr_warn("MMDC Perf PMU failed (%d), disabled\n", ret);
528 	cpuhp_state_remove_instance_nocalls(cpuhp_mmdc_state, &pmu_mmdc->node);
529 	hrtimer_cancel(&pmu_mmdc->hrtimer);
530 pmu_free:
531 	kfree(pmu_mmdc);
532 	return ret;
533 }
534 
535 #else
536 #define imx_mmdc_remove NULL
537 #define imx_mmdc_perf_init(pdev, mmdc_base, mmdc_ipg_clk) 0
538 #endif
539 
540 static int imx_mmdc_probe(struct platform_device *pdev)
541 {
542 	struct device_node *np = pdev->dev.of_node;
543 	void __iomem *mmdc_base, *reg;
544 	struct clk *mmdc_ipg_clk;
545 	u32 val;
546 	int err;
547 
548 	/* the ipg clock is optional */
549 	mmdc_ipg_clk = devm_clk_get(&pdev->dev, NULL);
550 	if (IS_ERR(mmdc_ipg_clk))
551 		mmdc_ipg_clk = NULL;
552 
553 	err = clk_prepare_enable(mmdc_ipg_clk);
554 	if (err) {
555 		dev_err(&pdev->dev, "Unable to enable mmdc ipg clock.\n");
556 		return err;
557 	}
558 
559 	mmdc_base = of_iomap(np, 0);
560 	WARN_ON(!mmdc_base);
561 
562 	reg = mmdc_base + MMDC_MDMISC;
563 	/* Get ddr type */
564 	val = readl_relaxed(reg);
565 	ddr_type = (val & BM_MMDC_MDMISC_DDR_TYPE) >>
566 		 BP_MMDC_MDMISC_DDR_TYPE;
567 
568 	reg = mmdc_base + MMDC_MAPSR;
569 
570 	/* Enable automatic power saving */
571 	val = readl_relaxed(reg);
572 	val &= ~(1 << BP_MMDC_MAPSR_PSD);
573 	writel_relaxed(val, reg);
574 
575 	err = imx_mmdc_perf_init(pdev, mmdc_base, mmdc_ipg_clk);
576 	if (err) {
577 		iounmap(mmdc_base);
578 		clk_disable_unprepare(mmdc_ipg_clk);
579 	}
580 
581 	return err;
582 }
583 
584 int imx_mmdc_get_ddr_type(void)
585 {
586 	return ddr_type;
587 }
588 
589 static struct platform_driver imx_mmdc_driver = {
590 	.driver		= {
591 		.name	= "imx-mmdc",
592 		.of_match_table = imx_mmdc_dt_ids,
593 	},
594 	.probe		= imx_mmdc_probe,
595 	.remove		= imx_mmdc_remove,
596 };
597 
598 static int __init imx_mmdc_init(void)
599 {
600 	return platform_driver_register(&imx_mmdc_driver);
601 }
602 postcore_initcall(imx_mmdc_init);
603