xref: /openbmc/linux/arch/arm/mach-imx/mmdc.c (revision 5b4cb650)
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.exclude_user		||
298 			event->attr.exclude_kernel	||
299 			event->attr.exclude_hv		||
300 			event->attr.exclude_idle	||
301 			event->attr.exclude_host	||
302 			event->attr.exclude_guest	||
303 			event->attr.sample_period)
304 		return -EINVAL;
305 
306 	if (cfg < 0 || cfg >= MMDC_NUM_COUNTERS)
307 		return -EINVAL;
308 
309 	if (!mmdc_pmu_group_is_valid(event))
310 		return -EINVAL;
311 
312 	event->cpu = cpumask_first(&pmu_mmdc->cpu);
313 	return 0;
314 }
315 
316 static void mmdc_pmu_event_update(struct perf_event *event)
317 {
318 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
319 	struct hw_perf_event *hwc = &event->hw;
320 	u64 delta, prev_raw_count, new_raw_count;
321 
322 	do {
323 		prev_raw_count = local64_read(&hwc->prev_count);
324 		new_raw_count = mmdc_pmu_read_counter(pmu_mmdc,
325 						      event->attr.config);
326 	} while (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
327 		new_raw_count) != prev_raw_count);
328 
329 	delta = (new_raw_count - prev_raw_count) & 0xFFFFFFFF;
330 
331 	local64_add(delta, &event->count);
332 }
333 
334 static void mmdc_pmu_event_start(struct perf_event *event, int flags)
335 {
336 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
337 	struct hw_perf_event *hwc = &event->hw;
338 	void __iomem *mmdc_base, *reg;
339 	u32 val;
340 
341 	mmdc_base = pmu_mmdc->mmdc_base;
342 	reg = mmdc_base + MMDC_MADPCR0;
343 
344 	/*
345 	 * hrtimer is required because mmdc does not provide an interrupt so
346 	 * polling is necessary
347 	 */
348 	hrtimer_start(&pmu_mmdc->hrtimer, mmdc_pmu_timer_period(),
349 			HRTIMER_MODE_REL_PINNED);
350 
351 	local64_set(&hwc->prev_count, 0);
352 
353 	writel(DBG_RST, reg);
354 
355 	/*
356 	 * Write the AXI id parameter to MADPCR1.
357 	 */
358 	val = event->attr.config1;
359 	reg = mmdc_base + MMDC_MADPCR1;
360 	writel(val, reg);
361 
362 	reg = mmdc_base + MMDC_MADPCR0;
363 	val = DBG_EN;
364 	if (pmu_mmdc->devtype_data->flags & MMDC_FLAG_PROFILE_SEL)
365 		val |= PROFILE_SEL;
366 
367 	writel(val, reg);
368 }
369 
370 static int mmdc_pmu_event_add(struct perf_event *event, int flags)
371 {
372 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
373 	struct hw_perf_event *hwc = &event->hw;
374 
375 	int cfg = event->attr.config;
376 
377 	if (flags & PERF_EF_START)
378 		mmdc_pmu_event_start(event, flags);
379 
380 	if (pmu_mmdc->mmdc_events[cfg] != NULL)
381 		return -EAGAIN;
382 
383 	pmu_mmdc->mmdc_events[cfg] = event;
384 	pmu_mmdc->active_events++;
385 
386 	local64_set(&hwc->prev_count, mmdc_pmu_read_counter(pmu_mmdc, cfg));
387 
388 	return 0;
389 }
390 
391 static void mmdc_pmu_event_stop(struct perf_event *event, int flags)
392 {
393 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
394 	void __iomem *mmdc_base, *reg;
395 
396 	mmdc_base = pmu_mmdc->mmdc_base;
397 	reg = mmdc_base + MMDC_MADPCR0;
398 
399 	writel(PRF_FRZ, reg);
400 
401 	reg = mmdc_base + MMDC_MADPCR1;
402 	writel(MMDC_PRF_AXI_ID_CLEAR, reg);
403 
404 	mmdc_pmu_event_update(event);
405 }
406 
407 static void mmdc_pmu_event_del(struct perf_event *event, int flags)
408 {
409 	struct mmdc_pmu *pmu_mmdc = to_mmdc_pmu(event->pmu);
410 	int cfg = event->attr.config;
411 
412 	pmu_mmdc->mmdc_events[cfg] = NULL;
413 	pmu_mmdc->active_events--;
414 
415 	if (pmu_mmdc->active_events == 0)
416 		hrtimer_cancel(&pmu_mmdc->hrtimer);
417 
418 	mmdc_pmu_event_stop(event, PERF_EF_UPDATE);
419 }
420 
421 static void mmdc_pmu_overflow_handler(struct mmdc_pmu *pmu_mmdc)
422 {
423 	int i;
424 
425 	for (i = 0; i < MMDC_NUM_COUNTERS; i++) {
426 		struct perf_event *event = pmu_mmdc->mmdc_events[i];
427 
428 		if (event)
429 			mmdc_pmu_event_update(event);
430 	}
431 }
432 
433 static enum hrtimer_restart mmdc_pmu_timer_handler(struct hrtimer *hrtimer)
434 {
435 	struct mmdc_pmu *pmu_mmdc = container_of(hrtimer, struct mmdc_pmu,
436 			hrtimer);
437 
438 	mmdc_pmu_overflow_handler(pmu_mmdc);
439 	hrtimer_forward_now(hrtimer, mmdc_pmu_timer_period());
440 
441 	return HRTIMER_RESTART;
442 }
443 
444 static int mmdc_pmu_init(struct mmdc_pmu *pmu_mmdc,
445 		void __iomem *mmdc_base, struct device *dev)
446 {
447 	int mmdc_num;
448 
449 	*pmu_mmdc = (struct mmdc_pmu) {
450 		.pmu = (struct pmu) {
451 			.task_ctx_nr    = perf_invalid_context,
452 			.attr_groups    = attr_groups,
453 			.event_init     = mmdc_pmu_event_init,
454 			.add            = mmdc_pmu_event_add,
455 			.del            = mmdc_pmu_event_del,
456 			.start          = mmdc_pmu_event_start,
457 			.stop           = mmdc_pmu_event_stop,
458 			.read           = mmdc_pmu_event_update,
459 		},
460 		.mmdc_base = mmdc_base,
461 		.dev = dev,
462 		.active_events = 0,
463 	};
464 
465 	mmdc_num = ida_simple_get(&mmdc_ida, 0, 0, GFP_KERNEL);
466 
467 	return mmdc_num;
468 }
469 
470 static int imx_mmdc_remove(struct platform_device *pdev)
471 {
472 	struct mmdc_pmu *pmu_mmdc = platform_get_drvdata(pdev);
473 
474 	cpuhp_state_remove_instance_nocalls(cpuhp_mmdc_state, &pmu_mmdc->node);
475 	perf_pmu_unregister(&pmu_mmdc->pmu);
476 	kfree(pmu_mmdc);
477 	return 0;
478 }
479 
480 static int imx_mmdc_perf_init(struct platform_device *pdev, void __iomem *mmdc_base)
481 {
482 	struct mmdc_pmu *pmu_mmdc;
483 	char *name;
484 	int mmdc_num;
485 	int ret;
486 	const struct of_device_id *of_id =
487 		of_match_device(imx_mmdc_dt_ids, &pdev->dev);
488 
489 	pmu_mmdc = kzalloc(sizeof(*pmu_mmdc), GFP_KERNEL);
490 	if (!pmu_mmdc) {
491 		pr_err("failed to allocate PMU device!\n");
492 		return -ENOMEM;
493 	}
494 
495 	/* The first instance registers the hotplug state */
496 	if (!cpuhp_mmdc_state) {
497 		ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN,
498 					      "perf/arm/mmdc:online", NULL,
499 					      mmdc_pmu_offline_cpu);
500 		if (ret < 0) {
501 			pr_err("cpuhp_setup_state_multi failed\n");
502 			goto pmu_free;
503 		}
504 		cpuhp_mmdc_state = ret;
505 	}
506 
507 	mmdc_num = mmdc_pmu_init(pmu_mmdc, mmdc_base, &pdev->dev);
508 	if (mmdc_num == 0)
509 		name = "mmdc";
510 	else
511 		name = devm_kasprintf(&pdev->dev,
512 				GFP_KERNEL, "mmdc%d", mmdc_num);
513 
514 	pmu_mmdc->devtype_data = (struct fsl_mmdc_devtype_data *)of_id->data;
515 
516 	hrtimer_init(&pmu_mmdc->hrtimer, CLOCK_MONOTONIC,
517 			HRTIMER_MODE_REL);
518 	pmu_mmdc->hrtimer.function = mmdc_pmu_timer_handler;
519 
520 	cpumask_set_cpu(raw_smp_processor_id(), &pmu_mmdc->cpu);
521 
522 	/* Register the pmu instance for cpu hotplug */
523 	cpuhp_state_add_instance_nocalls(cpuhp_mmdc_state, &pmu_mmdc->node);
524 
525 	ret = perf_pmu_register(&(pmu_mmdc->pmu), name, -1);
526 	if (ret)
527 		goto pmu_register_err;
528 
529 	platform_set_drvdata(pdev, pmu_mmdc);
530 	return 0;
531 
532 pmu_register_err:
533 	pr_warn("MMDC Perf PMU failed (%d), disabled\n", ret);
534 	cpuhp_state_remove_instance_nocalls(cpuhp_mmdc_state, &pmu_mmdc->node);
535 	hrtimer_cancel(&pmu_mmdc->hrtimer);
536 pmu_free:
537 	kfree(pmu_mmdc);
538 	return ret;
539 }
540 
541 #else
542 #define imx_mmdc_remove NULL
543 #define imx_mmdc_perf_init(pdev, mmdc_base) 0
544 #endif
545 
546 static int imx_mmdc_probe(struct platform_device *pdev)
547 {
548 	struct device_node *np = pdev->dev.of_node;
549 	void __iomem *mmdc_base, *reg;
550 	struct clk *mmdc_ipg_clk;
551 	u32 val;
552 	int err;
553 
554 	/* the ipg clock is optional */
555 	mmdc_ipg_clk = devm_clk_get(&pdev->dev, NULL);
556 	if (IS_ERR(mmdc_ipg_clk))
557 		mmdc_ipg_clk = NULL;
558 
559 	err = clk_prepare_enable(mmdc_ipg_clk);
560 	if (err) {
561 		dev_err(&pdev->dev, "Unable to enable mmdc ipg clock.\n");
562 		return err;
563 	}
564 
565 	mmdc_base = of_iomap(np, 0);
566 	WARN_ON(!mmdc_base);
567 
568 	reg = mmdc_base + MMDC_MDMISC;
569 	/* Get ddr type */
570 	val = readl_relaxed(reg);
571 	ddr_type = (val & BM_MMDC_MDMISC_DDR_TYPE) >>
572 		 BP_MMDC_MDMISC_DDR_TYPE;
573 
574 	reg = mmdc_base + MMDC_MAPSR;
575 
576 	/* Enable automatic power saving */
577 	val = readl_relaxed(reg);
578 	val &= ~(1 << BP_MMDC_MAPSR_PSD);
579 	writel_relaxed(val, reg);
580 
581 	return imx_mmdc_perf_init(pdev, mmdc_base);
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