xref: /openbmc/linux/drivers/memory/tegra/tegra20.c (revision 63705da3)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2012 NVIDIA CORPORATION.  All rights reserved.
4  */
5 
6 #include <linux/bitfield.h>
7 #include <linux/delay.h>
8 #include <linux/mutex.h>
9 #include <linux/of_device.h>
10 #include <linux/slab.h>
11 #include <linux/string.h>
12 
13 #include <dt-bindings/memory/tegra20-mc.h>
14 
15 #include "mc.h"
16 
17 #define MC_STAT_CONTROL				0x90
18 #define MC_STAT_EMC_CLOCK_LIMIT			0xa0
19 #define MC_STAT_EMC_CLOCKS			0xa4
20 #define MC_STAT_EMC_CONTROL_0			0xa8
21 #define MC_STAT_EMC_CONTROL_1			0xac
22 #define MC_STAT_EMC_COUNT_0			0xb8
23 #define MC_STAT_EMC_COUNT_1			0xbc
24 
25 #define MC_STAT_CONTROL_CLIENT_ID		GENMASK(13,  8)
26 #define MC_STAT_CONTROL_EVENT			GENMASK(23, 16)
27 #define MC_STAT_CONTROL_PRI_EVENT		GENMASK(25, 24)
28 #define MC_STAT_CONTROL_FILTER_CLIENT_ENABLE	GENMASK(26, 26)
29 #define MC_STAT_CONTROL_FILTER_PRI		GENMASK(29, 28)
30 
31 #define MC_STAT_CONTROL_PRI_EVENT_HP		0
32 #define MC_STAT_CONTROL_PRI_EVENT_TM		1
33 #define MC_STAT_CONTROL_PRI_EVENT_BW		2
34 
35 #define MC_STAT_CONTROL_FILTER_PRI_DISABLE	0
36 #define MC_STAT_CONTROL_FILTER_PRI_NO		1
37 #define MC_STAT_CONTROL_FILTER_PRI_YES		2
38 
39 #define MC_STAT_CONTROL_EVENT_QUALIFIED		0
40 #define MC_STAT_CONTROL_EVENT_ANY_READ		1
41 #define MC_STAT_CONTROL_EVENT_ANY_WRITE		2
42 #define MC_STAT_CONTROL_EVENT_RD_WR_CHANGE	3
43 #define MC_STAT_CONTROL_EVENT_SUCCESSIVE	4
44 #define MC_STAT_CONTROL_EVENT_ARB_BANK_AA	5
45 #define MC_STAT_CONTROL_EVENT_ARB_BANK_BB	6
46 #define MC_STAT_CONTROL_EVENT_PAGE_MISS		7
47 #define MC_STAT_CONTROL_EVENT_AUTO_PRECHARGE	8
48 
49 #define EMC_GATHER_RST				(0 << 8)
50 #define EMC_GATHER_CLEAR			(1 << 8)
51 #define EMC_GATHER_DISABLE			(2 << 8)
52 #define EMC_GATHER_ENABLE			(3 << 8)
53 
54 #define MC_STAT_SAMPLE_TIME_USEC		16000
55 
56 /* we store collected statistics as a fixed point values */
57 #define MC_FX_FRAC_SCALE			100
58 
59 static DEFINE_MUTEX(tegra20_mc_stat_lock);
60 
61 struct tegra20_mc_stat_gather {
62 	unsigned int pri_filter;
63 	unsigned int pri_event;
64 	unsigned int result;
65 	unsigned int client;
66 	unsigned int event;
67 	bool client_enb;
68 };
69 
70 struct tegra20_mc_stat {
71 	struct tegra20_mc_stat_gather gather0;
72 	struct tegra20_mc_stat_gather gather1;
73 	unsigned int sample_time_usec;
74 	const struct tegra_mc *mc;
75 };
76 
77 struct tegra20_mc_client_stat {
78 	unsigned int events;
79 	unsigned int arb_high_prio;
80 	unsigned int arb_timeout;
81 	unsigned int arb_bandwidth;
82 	unsigned int rd_wr_change;
83 	unsigned int successive;
84 	unsigned int page_miss;
85 	unsigned int auto_precharge;
86 	unsigned int arb_bank_aa;
87 	unsigned int arb_bank_bb;
88 };
89 
90 static const struct tegra_mc_client tegra20_mc_clients[] = {
91 	{
92 		.id = 0x00,
93 		.name = "display0a",
94 	}, {
95 		.id = 0x01,
96 		.name = "display0ab",
97 	}, {
98 		.id = 0x02,
99 		.name = "display0b",
100 	}, {
101 		.id = 0x03,
102 		.name = "display0bb",
103 	}, {
104 		.id = 0x04,
105 		.name = "display0c",
106 	}, {
107 		.id = 0x05,
108 		.name = "display0cb",
109 	}, {
110 		.id = 0x06,
111 		.name = "display1b",
112 	}, {
113 		.id = 0x07,
114 		.name = "display1bb",
115 	}, {
116 		.id = 0x08,
117 		.name = "eppup",
118 	}, {
119 		.id = 0x09,
120 		.name = "g2pr",
121 	}, {
122 		.id = 0x0a,
123 		.name = "g2sr",
124 	}, {
125 		.id = 0x0b,
126 		.name = "mpeunifbr",
127 	}, {
128 		.id = 0x0c,
129 		.name = "viruv",
130 	}, {
131 		.id = 0x0d,
132 		.name = "avpcarm7r",
133 	}, {
134 		.id = 0x0e,
135 		.name = "displayhc",
136 	}, {
137 		.id = 0x0f,
138 		.name = "displayhcb",
139 	}, {
140 		.id = 0x10,
141 		.name = "fdcdrd",
142 	}, {
143 		.id = 0x11,
144 		.name = "g2dr",
145 	}, {
146 		.id = 0x12,
147 		.name = "host1xdmar",
148 	}, {
149 		.id = 0x13,
150 		.name = "host1xr",
151 	}, {
152 		.id = 0x14,
153 		.name = "idxsrd",
154 	}, {
155 		.id = 0x15,
156 		.name = "mpcorer",
157 	}, {
158 		.id = 0x16,
159 		.name = "mpe_ipred",
160 	}, {
161 		.id = 0x17,
162 		.name = "mpeamemrd",
163 	}, {
164 		.id = 0x18,
165 		.name = "mpecsrd",
166 	}, {
167 		.id = 0x19,
168 		.name = "ppcsahbdmar",
169 	}, {
170 		.id = 0x1a,
171 		.name = "ppcsahbslvr",
172 	}, {
173 		.id = 0x1b,
174 		.name = "texsrd",
175 	}, {
176 		.id = 0x1c,
177 		.name = "vdebsevr",
178 	}, {
179 		.id = 0x1d,
180 		.name = "vdember",
181 	}, {
182 		.id = 0x1e,
183 		.name = "vdemcer",
184 	}, {
185 		.id = 0x1f,
186 		.name = "vdetper",
187 	}, {
188 		.id = 0x20,
189 		.name = "eppu",
190 	}, {
191 		.id = 0x21,
192 		.name = "eppv",
193 	}, {
194 		.id = 0x22,
195 		.name = "eppy",
196 	}, {
197 		.id = 0x23,
198 		.name = "mpeunifbw",
199 	}, {
200 		.id = 0x24,
201 		.name = "viwsb",
202 	}, {
203 		.id = 0x25,
204 		.name = "viwu",
205 	}, {
206 		.id = 0x26,
207 		.name = "viwv",
208 	}, {
209 		.id = 0x27,
210 		.name = "viwy",
211 	}, {
212 		.id = 0x28,
213 		.name = "g2dw",
214 	}, {
215 		.id = 0x29,
216 		.name = "avpcarm7w",
217 	}, {
218 		.id = 0x2a,
219 		.name = "fdcdwr",
220 	}, {
221 		.id = 0x2b,
222 		.name = "host1xw",
223 	}, {
224 		.id = 0x2c,
225 		.name = "ispw",
226 	}, {
227 		.id = 0x2d,
228 		.name = "mpcorew",
229 	}, {
230 		.id = 0x2e,
231 		.name = "mpecswr",
232 	}, {
233 		.id = 0x2f,
234 		.name = "ppcsahbdmaw",
235 	}, {
236 		.id = 0x30,
237 		.name = "ppcsahbslvw",
238 	}, {
239 		.id = 0x31,
240 		.name = "vdebsevw",
241 	}, {
242 		.id = 0x32,
243 		.name = "vdembew",
244 	}, {
245 		.id = 0x33,
246 		.name = "vdetpmw",
247 	},
248 };
249 
250 #define TEGRA20_MC_RESET(_name, _control, _status, _reset, _bit)	\
251 	{								\
252 		.name = #_name,						\
253 		.id = TEGRA20_MC_RESET_##_name,				\
254 		.control = _control,					\
255 		.status = _status,					\
256 		.reset = _reset,					\
257 		.bit = _bit,						\
258 	}
259 
260 static const struct tegra_mc_reset tegra20_mc_resets[] = {
261 	TEGRA20_MC_RESET(AVPC,   0x100, 0x140, 0x104,  0),
262 	TEGRA20_MC_RESET(DC,     0x100, 0x144, 0x104,  1),
263 	TEGRA20_MC_RESET(DCB,    0x100, 0x148, 0x104,  2),
264 	TEGRA20_MC_RESET(EPP,    0x100, 0x14c, 0x104,  3),
265 	TEGRA20_MC_RESET(2D,     0x100, 0x150, 0x104,  4),
266 	TEGRA20_MC_RESET(HC,     0x100, 0x154, 0x104,  5),
267 	TEGRA20_MC_RESET(ISP,    0x100, 0x158, 0x104,  6),
268 	TEGRA20_MC_RESET(MPCORE, 0x100, 0x15c, 0x104,  7),
269 	TEGRA20_MC_RESET(MPEA,   0x100, 0x160, 0x104,  8),
270 	TEGRA20_MC_RESET(MPEB,   0x100, 0x164, 0x104,  9),
271 	TEGRA20_MC_RESET(MPEC,   0x100, 0x168, 0x104, 10),
272 	TEGRA20_MC_RESET(3D,     0x100, 0x16c, 0x104, 11),
273 	TEGRA20_MC_RESET(PPCS,   0x100, 0x170, 0x104, 12),
274 	TEGRA20_MC_RESET(VDE,    0x100, 0x174, 0x104, 13),
275 	TEGRA20_MC_RESET(VI,     0x100, 0x178, 0x104, 14),
276 };
277 
278 static int tegra20_mc_hotreset_assert(struct tegra_mc *mc,
279 				      const struct tegra_mc_reset *rst)
280 {
281 	unsigned long flags;
282 	u32 value;
283 
284 	spin_lock_irqsave(&mc->lock, flags);
285 
286 	value = mc_readl(mc, rst->reset);
287 	mc_writel(mc, value & ~BIT(rst->bit), rst->reset);
288 
289 	spin_unlock_irqrestore(&mc->lock, flags);
290 
291 	return 0;
292 }
293 
294 static int tegra20_mc_hotreset_deassert(struct tegra_mc *mc,
295 					const struct tegra_mc_reset *rst)
296 {
297 	unsigned long flags;
298 	u32 value;
299 
300 	spin_lock_irqsave(&mc->lock, flags);
301 
302 	value = mc_readl(mc, rst->reset);
303 	mc_writel(mc, value | BIT(rst->bit), rst->reset);
304 
305 	spin_unlock_irqrestore(&mc->lock, flags);
306 
307 	return 0;
308 }
309 
310 static int tegra20_mc_block_dma(struct tegra_mc *mc,
311 				const struct tegra_mc_reset *rst)
312 {
313 	unsigned long flags;
314 	u32 value;
315 
316 	spin_lock_irqsave(&mc->lock, flags);
317 
318 	value = mc_readl(mc, rst->control) & ~BIT(rst->bit);
319 	mc_writel(mc, value, rst->control);
320 
321 	spin_unlock_irqrestore(&mc->lock, flags);
322 
323 	return 0;
324 }
325 
326 static bool tegra20_mc_dma_idling(struct tegra_mc *mc,
327 				  const struct tegra_mc_reset *rst)
328 {
329 	return mc_readl(mc, rst->status) == 0;
330 }
331 
332 static int tegra20_mc_reset_status(struct tegra_mc *mc,
333 				   const struct tegra_mc_reset *rst)
334 {
335 	return (mc_readl(mc, rst->reset) & BIT(rst->bit)) == 0;
336 }
337 
338 static int tegra20_mc_unblock_dma(struct tegra_mc *mc,
339 				  const struct tegra_mc_reset *rst)
340 {
341 	unsigned long flags;
342 	u32 value;
343 
344 	spin_lock_irqsave(&mc->lock, flags);
345 
346 	value = mc_readl(mc, rst->control) | BIT(rst->bit);
347 	mc_writel(mc, value, rst->control);
348 
349 	spin_unlock_irqrestore(&mc->lock, flags);
350 
351 	return 0;
352 }
353 
354 static const struct tegra_mc_reset_ops tegra20_mc_reset_ops = {
355 	.hotreset_assert = tegra20_mc_hotreset_assert,
356 	.hotreset_deassert = tegra20_mc_hotreset_deassert,
357 	.block_dma = tegra20_mc_block_dma,
358 	.dma_idling = tegra20_mc_dma_idling,
359 	.unblock_dma = tegra20_mc_unblock_dma,
360 	.reset_status = tegra20_mc_reset_status,
361 };
362 
363 static int tegra20_mc_icc_set(struct icc_node *src, struct icc_node *dst)
364 {
365 	/*
366 	 * It should be possible to tune arbitration knobs here, but the
367 	 * default values are known to work well on all devices. Hence
368 	 * nothing to do here so far.
369 	 */
370 	return 0;
371 }
372 
373 static int tegra20_mc_icc_aggreate(struct icc_node *node, u32 tag, u32 avg_bw,
374 				   u32 peak_bw, u32 *agg_avg, u32 *agg_peak)
375 {
376 	/*
377 	 * ISO clients need to reserve extra bandwidth up-front because
378 	 * there could be high bandwidth pressure during initial filling
379 	 * of the client's FIFO buffers.  Secondly, we need to take into
380 	 * account impurities of the memory subsystem.
381 	 */
382 	if (tag & TEGRA_MC_ICC_TAG_ISO)
383 		peak_bw = tegra_mc_scale_percents(peak_bw, 300);
384 
385 	*agg_avg += avg_bw;
386 	*agg_peak = max(*agg_peak, peak_bw);
387 
388 	return 0;
389 }
390 
391 static struct icc_node_data *
392 tegra20_mc_of_icc_xlate_extended(struct of_phandle_args *spec, void *data)
393 {
394 	struct tegra_mc *mc = icc_provider_to_tegra_mc(data);
395 	unsigned int i, idx = spec->args[0];
396 	struct icc_node_data *ndata;
397 	struct icc_node *node;
398 
399 	list_for_each_entry(node, &mc->provider.nodes, node_list) {
400 		if (node->id != idx)
401 			continue;
402 
403 		ndata = kzalloc(sizeof(*ndata), GFP_KERNEL);
404 		if (!ndata)
405 			return ERR_PTR(-ENOMEM);
406 
407 		ndata->node = node;
408 
409 		/* these clients are isochronous by default */
410 		if (strstarts(node->name, "display") ||
411 		    strstarts(node->name, "vi"))
412 			ndata->tag = TEGRA_MC_ICC_TAG_ISO;
413 		else
414 			ndata->tag = TEGRA_MC_ICC_TAG_DEFAULT;
415 
416 		return ndata;
417 	}
418 
419 	for (i = 0; i < mc->soc->num_clients; i++) {
420 		if (mc->soc->clients[i].id == idx)
421 			return ERR_PTR(-EPROBE_DEFER);
422 	}
423 
424 	dev_err(mc->dev, "invalid ICC client ID %u\n", idx);
425 
426 	return ERR_PTR(-EINVAL);
427 }
428 
429 static const struct tegra_mc_icc_ops tegra20_mc_icc_ops = {
430 	.xlate_extended = tegra20_mc_of_icc_xlate_extended,
431 	.aggregate = tegra20_mc_icc_aggreate,
432 	.set = tegra20_mc_icc_set,
433 };
434 
435 static u32 tegra20_mc_stat_gather_control(const struct tegra20_mc_stat_gather *g)
436 {
437 	u32 control;
438 
439 	control  = FIELD_PREP(MC_STAT_CONTROL_EVENT, g->event);
440 	control |= FIELD_PREP(MC_STAT_CONTROL_CLIENT_ID, g->client);
441 	control |= FIELD_PREP(MC_STAT_CONTROL_PRI_EVENT, g->pri_event);
442 	control |= FIELD_PREP(MC_STAT_CONTROL_FILTER_PRI, g->pri_filter);
443 	control |= FIELD_PREP(MC_STAT_CONTROL_FILTER_CLIENT_ENABLE, g->client_enb);
444 
445 	return control;
446 }
447 
448 static void tegra20_mc_stat_gather(struct tegra20_mc_stat *stat)
449 {
450 	u32 clocks, count0, count1, control_0, control_1;
451 	const struct tegra_mc *mc = stat->mc;
452 
453 	control_0 = tegra20_mc_stat_gather_control(&stat->gather0);
454 	control_1 = tegra20_mc_stat_gather_control(&stat->gather1);
455 
456 	/*
457 	 * Reset statistic gathers state, select statistics collection mode
458 	 * and set clocks counter saturation limit to maximum.
459 	 */
460 	mc_writel(mc, 0x00000000, MC_STAT_CONTROL);
461 	mc_writel(mc,  control_0, MC_STAT_EMC_CONTROL_0);
462 	mc_writel(mc,  control_1, MC_STAT_EMC_CONTROL_1);
463 	mc_writel(mc, 0xffffffff, MC_STAT_EMC_CLOCK_LIMIT);
464 
465 	mc_writel(mc, EMC_GATHER_ENABLE, MC_STAT_CONTROL);
466 	fsleep(stat->sample_time_usec);
467 	mc_writel(mc, EMC_GATHER_DISABLE, MC_STAT_CONTROL);
468 
469 	count0 = mc_readl(mc, MC_STAT_EMC_COUNT_0);
470 	count1 = mc_readl(mc, MC_STAT_EMC_COUNT_1);
471 	clocks = mc_readl(mc, MC_STAT_EMC_CLOCKS);
472 	clocks = max(clocks / 100 / MC_FX_FRAC_SCALE, 1u);
473 
474 	stat->gather0.result = DIV_ROUND_UP(count0, clocks);
475 	stat->gather1.result = DIV_ROUND_UP(count1, clocks);
476 }
477 
478 static void tegra20_mc_stat_events(const struct tegra_mc *mc,
479 				   const struct tegra_mc_client *client0,
480 				   const struct tegra_mc_client *client1,
481 				   unsigned int pri_filter,
482 				   unsigned int pri_event,
483 				   unsigned int event,
484 				   unsigned int *result0,
485 				   unsigned int *result1)
486 {
487 	struct tegra20_mc_stat stat = {};
488 
489 	stat.gather0.client = client0 ? client0->id : 0;
490 	stat.gather0.pri_filter = pri_filter;
491 	stat.gather0.client_enb = !!client0;
492 	stat.gather0.pri_event = pri_event;
493 	stat.gather0.event = event;
494 
495 	stat.gather1.client = client1 ? client1->id : 0;
496 	stat.gather1.pri_filter = pri_filter;
497 	stat.gather1.client_enb = !!client1;
498 	stat.gather1.pri_event = pri_event;
499 	stat.gather1.event = event;
500 
501 	stat.sample_time_usec = MC_STAT_SAMPLE_TIME_USEC;
502 	stat.mc = mc;
503 
504 	tegra20_mc_stat_gather(&stat);
505 
506 	*result0 = stat.gather0.result;
507 	*result1 = stat.gather1.result;
508 }
509 
510 static void tegra20_mc_collect_stats(const struct tegra_mc *mc,
511 				     struct tegra20_mc_client_stat *stats)
512 {
513 	const struct tegra_mc_client *client0, *client1;
514 	unsigned int i;
515 
516 	/* collect memory controller utilization percent for each client */
517 	for (i = 0; i < mc->soc->num_clients; i += 2) {
518 		client0 = &mc->soc->clients[i];
519 		client1 = &mc->soc->clients[i + 1];
520 
521 		if (i + 1 == mc->soc->num_clients)
522 			client1 = NULL;
523 
524 		tegra20_mc_stat_events(mc, client0, client1,
525 				       MC_STAT_CONTROL_FILTER_PRI_DISABLE,
526 				       MC_STAT_CONTROL_PRI_EVENT_HP,
527 				       MC_STAT_CONTROL_EVENT_QUALIFIED,
528 				       &stats[i + 0].events,
529 				       &stats[i + 1].events);
530 	}
531 
532 	/* collect more info from active clients */
533 	for (i = 0; i < mc->soc->num_clients; i++) {
534 		unsigned int clienta, clientb = mc->soc->num_clients;
535 
536 		for (client0 = NULL; i < mc->soc->num_clients; i++) {
537 			if (stats[i].events) {
538 				client0 = &mc->soc->clients[i];
539 				clienta = i++;
540 				break;
541 			}
542 		}
543 
544 		for (client1 = NULL; i < mc->soc->num_clients; i++) {
545 			if (stats[i].events) {
546 				client1 = &mc->soc->clients[i];
547 				clientb = i;
548 				break;
549 			}
550 		}
551 
552 		if (!client0 && !client1)
553 			break;
554 
555 		tegra20_mc_stat_events(mc, client0, client1,
556 				       MC_STAT_CONTROL_FILTER_PRI_YES,
557 				       MC_STAT_CONTROL_PRI_EVENT_HP,
558 				       MC_STAT_CONTROL_EVENT_QUALIFIED,
559 				       &stats[clienta].arb_high_prio,
560 				       &stats[clientb].arb_high_prio);
561 
562 		tegra20_mc_stat_events(mc, client0, client1,
563 				       MC_STAT_CONTROL_FILTER_PRI_YES,
564 				       MC_STAT_CONTROL_PRI_EVENT_TM,
565 				       MC_STAT_CONTROL_EVENT_QUALIFIED,
566 				       &stats[clienta].arb_timeout,
567 				       &stats[clientb].arb_timeout);
568 
569 		tegra20_mc_stat_events(mc, client0, client1,
570 				       MC_STAT_CONTROL_FILTER_PRI_YES,
571 				       MC_STAT_CONTROL_PRI_EVENT_BW,
572 				       MC_STAT_CONTROL_EVENT_QUALIFIED,
573 				       &stats[clienta].arb_bandwidth,
574 				       &stats[clientb].arb_bandwidth);
575 
576 		tegra20_mc_stat_events(mc, client0, client1,
577 				       MC_STAT_CONTROL_FILTER_PRI_DISABLE,
578 				       MC_STAT_CONTROL_PRI_EVENT_HP,
579 				       MC_STAT_CONTROL_EVENT_RD_WR_CHANGE,
580 				       &stats[clienta].rd_wr_change,
581 				       &stats[clientb].rd_wr_change);
582 
583 		tegra20_mc_stat_events(mc, client0, client1,
584 				       MC_STAT_CONTROL_FILTER_PRI_DISABLE,
585 				       MC_STAT_CONTROL_PRI_EVENT_HP,
586 				       MC_STAT_CONTROL_EVENT_SUCCESSIVE,
587 				       &stats[clienta].successive,
588 				       &stats[clientb].successive);
589 
590 		tegra20_mc_stat_events(mc, client0, client1,
591 				       MC_STAT_CONTROL_FILTER_PRI_DISABLE,
592 				       MC_STAT_CONTROL_PRI_EVENT_HP,
593 				       MC_STAT_CONTROL_EVENT_PAGE_MISS,
594 				       &stats[clienta].page_miss,
595 				       &stats[clientb].page_miss);
596 	}
597 }
598 
599 static void tegra20_mc_printf_percents(struct seq_file *s,
600 				       const char *fmt,
601 				       unsigned int percents_fx)
602 {
603 	char percents_str[8];
604 
605 	snprintf(percents_str, ARRAY_SIZE(percents_str), "%3u.%02u%%",
606 		 percents_fx / MC_FX_FRAC_SCALE, percents_fx % MC_FX_FRAC_SCALE);
607 
608 	seq_printf(s, fmt, percents_str);
609 }
610 
611 static int tegra20_mc_stats_show(struct seq_file *s, void *unused)
612 {
613 	const struct tegra_mc *mc = dev_get_drvdata(s->private);
614 	struct tegra20_mc_client_stat *stats;
615 	unsigned int i;
616 
617 	stats = kcalloc(mc->soc->num_clients + 1, sizeof(*stats), GFP_KERNEL);
618 	if (!stats)
619 		return -ENOMEM;
620 
621 	mutex_lock(&tegra20_mc_stat_lock);
622 
623 	tegra20_mc_collect_stats(mc, stats);
624 
625 	mutex_unlock(&tegra20_mc_stat_lock);
626 
627 	seq_puts(s, "Memory client   Events   Timeout   High priority   Bandwidth ARB   RW change   Successive   Page miss\n");
628 	seq_puts(s, "-----------------------------------------------------------------------------------------------------\n");
629 
630 	for (i = 0; i < mc->soc->num_clients; i++) {
631 		seq_printf(s, "%-14s  ", mc->soc->clients[i].name);
632 
633 		/* An event is generated when client performs R/W request. */
634 		tegra20_mc_printf_percents(s,  "%-9s", stats[i].events);
635 
636 		/*
637 		 * An event is generated based on the timeout (TM) signal
638 		 * accompanying a request for arbitration.
639 		 */
640 		tegra20_mc_printf_percents(s, "%-10s", stats[i].arb_timeout);
641 
642 		/*
643 		 * An event is generated based on the high-priority (HP) signal
644 		 * accompanying a request for arbitration.
645 		 */
646 		tegra20_mc_printf_percents(s, "%-16s", stats[i].arb_high_prio);
647 
648 		/*
649 		 * An event is generated based on the bandwidth (BW) signal
650 		 * accompanying a request for arbitration.
651 		 */
652 		tegra20_mc_printf_percents(s, "%-16s", stats[i].arb_bandwidth);
653 
654 		/*
655 		 * An event is generated when the memory controller switches
656 		 * between making a read request to making a write request.
657 		 */
658 		tegra20_mc_printf_percents(s, "%-12s", stats[i].rd_wr_change);
659 
660 		/*
661 		 * An even generated when the chosen client has wins arbitration
662 		 * when it was also the winner at the previous request.  If a
663 		 * client makes N requests in a row that are honored, SUCCESSIVE
664 		 * will be counted (N-1) times.  Large values for this event
665 		 * imply that if we were patient enough, all of those requests
666 		 * could have been coalesced.
667 		 */
668 		tegra20_mc_printf_percents(s, "%-13s", stats[i].successive);
669 
670 		/*
671 		 * An event is generated when the memory controller detects a
672 		 * page miss for the current request.
673 		 */
674 		tegra20_mc_printf_percents(s, "%-12s\n", stats[i].page_miss);
675 	}
676 
677 	kfree(stats);
678 
679 	return 0;
680 }
681 
682 static int tegra20_mc_probe(struct tegra_mc *mc)
683 {
684 	debugfs_create_devm_seqfile(mc->dev, "stats", mc->debugfs.root,
685 				    tegra20_mc_stats_show);
686 
687 	return 0;
688 }
689 
690 static int tegra20_mc_suspend(struct tegra_mc *mc)
691 {
692 	int err;
693 
694 	if (IS_ENABLED(CONFIG_TEGRA_IOMMU_GART) && mc->gart) {
695 		err = tegra_gart_suspend(mc->gart);
696 		if (err < 0)
697 			return err;
698 	}
699 
700 	return 0;
701 }
702 
703 static int tegra20_mc_resume(struct tegra_mc *mc)
704 {
705 	int err;
706 
707 	if (IS_ENABLED(CONFIG_TEGRA_IOMMU_GART) && mc->gart) {
708 		err = tegra_gart_resume(mc->gart);
709 		if (err < 0)
710 			return err;
711 	}
712 
713 	return 0;
714 }
715 
716 static irqreturn_t tegra20_mc_handle_irq(int irq, void *data)
717 {
718 	struct tegra_mc *mc = data;
719 	unsigned long status;
720 	unsigned int bit;
721 
722 	/* mask all interrupts to avoid flooding */
723 	status = mc_readl(mc, MC_INTSTATUS) & mc->soc->intmask;
724 	if (!status)
725 		return IRQ_NONE;
726 
727 	for_each_set_bit(bit, &status, 32) {
728 		const char *error = tegra_mc_status_names[bit];
729 		const char *direction = "read", *secure = "";
730 		const char *client, *desc;
731 		phys_addr_t addr;
732 		u32 value, reg;
733 		u8 id, type;
734 
735 		switch (BIT(bit)) {
736 		case MC_INT_DECERR_EMEM:
737 			reg = MC_DECERR_EMEM_OTHERS_STATUS;
738 			value = mc_readl(mc, reg);
739 
740 			id = value & mc->soc->client_id_mask;
741 			desc = tegra_mc_error_names[2];
742 
743 			if (value & BIT(31))
744 				direction = "write";
745 			break;
746 
747 		case MC_INT_INVALID_GART_PAGE:
748 			reg = MC_GART_ERROR_REQ;
749 			value = mc_readl(mc, reg);
750 
751 			id = (value >> 1) & mc->soc->client_id_mask;
752 			desc = tegra_mc_error_names[2];
753 
754 			if (value & BIT(0))
755 				direction = "write";
756 			break;
757 
758 		case MC_INT_SECURITY_VIOLATION:
759 			reg = MC_SECURITY_VIOLATION_STATUS;
760 			value = mc_readl(mc, reg);
761 
762 			id = value & mc->soc->client_id_mask;
763 			type = (value & BIT(30)) ? 4 : 3;
764 			desc = tegra_mc_error_names[type];
765 			secure = "secure ";
766 
767 			if (value & BIT(31))
768 				direction = "write";
769 			break;
770 
771 		default:
772 			continue;
773 		}
774 
775 		client = mc->soc->clients[id].name;
776 		addr = mc_readl(mc, reg + sizeof(u32));
777 
778 		dev_err_ratelimited(mc->dev, "%s: %s%s @%pa: %s (%s)\n",
779 				    client, secure, direction, &addr, error,
780 				    desc);
781 	}
782 
783 	/* clear interrupts */
784 	mc_writel(mc, status, MC_INTSTATUS);
785 
786 	return IRQ_HANDLED;
787 }
788 
789 static const struct tegra_mc_ops tegra20_mc_ops = {
790 	.probe = tegra20_mc_probe,
791 	.suspend = tegra20_mc_suspend,
792 	.resume = tegra20_mc_resume,
793 	.handle_irq = tegra20_mc_handle_irq,
794 };
795 
796 const struct tegra_mc_soc tegra20_mc_soc = {
797 	.clients = tegra20_mc_clients,
798 	.num_clients = ARRAY_SIZE(tegra20_mc_clients),
799 	.num_address_bits = 32,
800 	.client_id_mask = 0x3f,
801 	.intmask = MC_INT_SECURITY_VIOLATION | MC_INT_INVALID_GART_PAGE |
802 		   MC_INT_DECERR_EMEM,
803 	.reset_ops = &tegra20_mc_reset_ops,
804 	.resets = tegra20_mc_resets,
805 	.num_resets = ARRAY_SIZE(tegra20_mc_resets),
806 	.icc_ops = &tegra20_mc_icc_ops,
807 	.ops = &tegra20_mc_ops,
808 };
809