xref: /openbmc/linux/drivers/memory/tegra/mc.c (revision d9fd5a71)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2014 NVIDIA CORPORATION.  All rights reserved.
4  */
5 
6 #include <linux/clk.h>
7 #include <linux/delay.h>
8 #include <linux/dma-mapping.h>
9 #include <linux/export.h>
10 #include <linux/interrupt.h>
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/of.h>
14 #include <linux/of_device.h>
15 #include <linux/platform_device.h>
16 #include <linux/slab.h>
17 #include <linux/sort.h>
18 
19 #include <soc/tegra/fuse.h>
20 
21 #include "mc.h"
22 
23 static const struct of_device_id tegra_mc_of_match[] = {
24 #ifdef CONFIG_ARCH_TEGRA_2x_SOC
25 	{ .compatible = "nvidia,tegra20-mc-gart", .data = &tegra20_mc_soc },
26 #endif
27 #ifdef CONFIG_ARCH_TEGRA_3x_SOC
28 	{ .compatible = "nvidia,tegra30-mc", .data = &tegra30_mc_soc },
29 #endif
30 #ifdef CONFIG_ARCH_TEGRA_114_SOC
31 	{ .compatible = "nvidia,tegra114-mc", .data = &tegra114_mc_soc },
32 #endif
33 #ifdef CONFIG_ARCH_TEGRA_124_SOC
34 	{ .compatible = "nvidia,tegra124-mc", .data = &tegra124_mc_soc },
35 #endif
36 #ifdef CONFIG_ARCH_TEGRA_132_SOC
37 	{ .compatible = "nvidia,tegra132-mc", .data = &tegra132_mc_soc },
38 #endif
39 #ifdef CONFIG_ARCH_TEGRA_210_SOC
40 	{ .compatible = "nvidia,tegra210-mc", .data = &tegra210_mc_soc },
41 #endif
42 	{ }
43 };
44 MODULE_DEVICE_TABLE(of, tegra_mc_of_match);
45 
46 static void tegra_mc_devm_action_put_device(void *data)
47 {
48 	struct tegra_mc *mc = data;
49 
50 	put_device(mc->dev);
51 }
52 
53 /**
54  * devm_tegra_memory_controller_get() - get Tegra Memory Controller handle
55  * @dev: device pointer for the consumer device
56  *
57  * This function will search for the Memory Controller node in a device-tree
58  * and retrieve the Memory Controller handle.
59  *
60  * Return: ERR_PTR() on error or a valid pointer to a struct tegra_mc.
61  */
62 struct tegra_mc *devm_tegra_memory_controller_get(struct device *dev)
63 {
64 	struct platform_device *pdev;
65 	struct device_node *np;
66 	struct tegra_mc *mc;
67 	int err;
68 
69 	np = of_parse_phandle(dev->of_node, "nvidia,memory-controller", 0);
70 	if (!np)
71 		return ERR_PTR(-ENOENT);
72 
73 	pdev = of_find_device_by_node(np);
74 	of_node_put(np);
75 	if (!pdev)
76 		return ERR_PTR(-ENODEV);
77 
78 	mc = platform_get_drvdata(pdev);
79 	if (!mc) {
80 		put_device(&pdev->dev);
81 		return ERR_PTR(-EPROBE_DEFER);
82 	}
83 
84 	err = devm_add_action(dev, tegra_mc_devm_action_put_device, mc);
85 	if (err) {
86 		put_device(mc->dev);
87 		return ERR_PTR(err);
88 	}
89 
90 	return mc;
91 }
92 EXPORT_SYMBOL_GPL(devm_tegra_memory_controller_get);
93 
94 static int tegra_mc_block_dma_common(struct tegra_mc *mc,
95 				     const struct tegra_mc_reset *rst)
96 {
97 	unsigned long flags;
98 	u32 value;
99 
100 	spin_lock_irqsave(&mc->lock, flags);
101 
102 	value = mc_readl(mc, rst->control) | BIT(rst->bit);
103 	mc_writel(mc, value, rst->control);
104 
105 	spin_unlock_irqrestore(&mc->lock, flags);
106 
107 	return 0;
108 }
109 
110 static bool tegra_mc_dma_idling_common(struct tegra_mc *mc,
111 				       const struct tegra_mc_reset *rst)
112 {
113 	return (mc_readl(mc, rst->status) & BIT(rst->bit)) != 0;
114 }
115 
116 static int tegra_mc_unblock_dma_common(struct tegra_mc *mc,
117 				       const struct tegra_mc_reset *rst)
118 {
119 	unsigned long flags;
120 	u32 value;
121 
122 	spin_lock_irqsave(&mc->lock, flags);
123 
124 	value = mc_readl(mc, rst->control) & ~BIT(rst->bit);
125 	mc_writel(mc, value, rst->control);
126 
127 	spin_unlock_irqrestore(&mc->lock, flags);
128 
129 	return 0;
130 }
131 
132 static int tegra_mc_reset_status_common(struct tegra_mc *mc,
133 					const struct tegra_mc_reset *rst)
134 {
135 	return (mc_readl(mc, rst->control) & BIT(rst->bit)) != 0;
136 }
137 
138 const struct tegra_mc_reset_ops tegra_mc_reset_ops_common = {
139 	.block_dma = tegra_mc_block_dma_common,
140 	.dma_idling = tegra_mc_dma_idling_common,
141 	.unblock_dma = tegra_mc_unblock_dma_common,
142 	.reset_status = tegra_mc_reset_status_common,
143 };
144 
145 static inline struct tegra_mc *reset_to_mc(struct reset_controller_dev *rcdev)
146 {
147 	return container_of(rcdev, struct tegra_mc, reset);
148 }
149 
150 static const struct tegra_mc_reset *tegra_mc_reset_find(struct tegra_mc *mc,
151 							unsigned long id)
152 {
153 	unsigned int i;
154 
155 	for (i = 0; i < mc->soc->num_resets; i++)
156 		if (mc->soc->resets[i].id == id)
157 			return &mc->soc->resets[i];
158 
159 	return NULL;
160 }
161 
162 static int tegra_mc_hotreset_assert(struct reset_controller_dev *rcdev,
163 				    unsigned long id)
164 {
165 	struct tegra_mc *mc = reset_to_mc(rcdev);
166 	const struct tegra_mc_reset_ops *rst_ops;
167 	const struct tegra_mc_reset *rst;
168 	int retries = 500;
169 	int err;
170 
171 	rst = tegra_mc_reset_find(mc, id);
172 	if (!rst)
173 		return -ENODEV;
174 
175 	rst_ops = mc->soc->reset_ops;
176 	if (!rst_ops)
177 		return -ENODEV;
178 
179 	/* DMA flushing will fail if reset is already asserted */
180 	if (rst_ops->reset_status) {
181 		/* check whether reset is asserted */
182 		if (rst_ops->reset_status(mc, rst))
183 			return 0;
184 	}
185 
186 	if (rst_ops->block_dma) {
187 		/* block clients DMA requests */
188 		err = rst_ops->block_dma(mc, rst);
189 		if (err) {
190 			dev_err(mc->dev, "failed to block %s DMA: %d\n",
191 				rst->name, err);
192 			return err;
193 		}
194 	}
195 
196 	if (rst_ops->dma_idling) {
197 		/* wait for completion of the outstanding DMA requests */
198 		while (!rst_ops->dma_idling(mc, rst)) {
199 			if (!retries--) {
200 				dev_err(mc->dev, "failed to flush %s DMA\n",
201 					rst->name);
202 				return -EBUSY;
203 			}
204 
205 			usleep_range(10, 100);
206 		}
207 	}
208 
209 	if (rst_ops->hotreset_assert) {
210 		/* clear clients DMA requests sitting before arbitration */
211 		err = rst_ops->hotreset_assert(mc, rst);
212 		if (err) {
213 			dev_err(mc->dev, "failed to hot reset %s: %d\n",
214 				rst->name, err);
215 			return err;
216 		}
217 	}
218 
219 	return 0;
220 }
221 
222 static int tegra_mc_hotreset_deassert(struct reset_controller_dev *rcdev,
223 				      unsigned long id)
224 {
225 	struct tegra_mc *mc = reset_to_mc(rcdev);
226 	const struct tegra_mc_reset_ops *rst_ops;
227 	const struct tegra_mc_reset *rst;
228 	int err;
229 
230 	rst = tegra_mc_reset_find(mc, id);
231 	if (!rst)
232 		return -ENODEV;
233 
234 	rst_ops = mc->soc->reset_ops;
235 	if (!rst_ops)
236 		return -ENODEV;
237 
238 	if (rst_ops->hotreset_deassert) {
239 		/* take out client from hot reset */
240 		err = rst_ops->hotreset_deassert(mc, rst);
241 		if (err) {
242 			dev_err(mc->dev, "failed to deassert hot reset %s: %d\n",
243 				rst->name, err);
244 			return err;
245 		}
246 	}
247 
248 	if (rst_ops->unblock_dma) {
249 		/* allow new DMA requests to proceed to arbitration */
250 		err = rst_ops->unblock_dma(mc, rst);
251 		if (err) {
252 			dev_err(mc->dev, "failed to unblock %s DMA : %d\n",
253 				rst->name, err);
254 			return err;
255 		}
256 	}
257 
258 	return 0;
259 }
260 
261 static int tegra_mc_hotreset_status(struct reset_controller_dev *rcdev,
262 				    unsigned long id)
263 {
264 	struct tegra_mc *mc = reset_to_mc(rcdev);
265 	const struct tegra_mc_reset_ops *rst_ops;
266 	const struct tegra_mc_reset *rst;
267 
268 	rst = tegra_mc_reset_find(mc, id);
269 	if (!rst)
270 		return -ENODEV;
271 
272 	rst_ops = mc->soc->reset_ops;
273 	if (!rst_ops)
274 		return -ENODEV;
275 
276 	return rst_ops->reset_status(mc, rst);
277 }
278 
279 static const struct reset_control_ops tegra_mc_reset_ops = {
280 	.assert = tegra_mc_hotreset_assert,
281 	.deassert = tegra_mc_hotreset_deassert,
282 	.status = tegra_mc_hotreset_status,
283 };
284 
285 static int tegra_mc_reset_setup(struct tegra_mc *mc)
286 {
287 	int err;
288 
289 	mc->reset.ops = &tegra_mc_reset_ops;
290 	mc->reset.owner = THIS_MODULE;
291 	mc->reset.of_node = mc->dev->of_node;
292 	mc->reset.of_reset_n_cells = 1;
293 	mc->reset.nr_resets = mc->soc->num_resets;
294 
295 	err = reset_controller_register(&mc->reset);
296 	if (err < 0)
297 		return err;
298 
299 	return 0;
300 }
301 
302 static int tegra_mc_setup_latency_allowance(struct tegra_mc *mc)
303 {
304 	unsigned long long tick;
305 	unsigned int i;
306 	u32 value;
307 
308 	/* compute the number of MC clock cycles per tick */
309 	tick = (unsigned long long)mc->tick * clk_get_rate(mc->clk);
310 	do_div(tick, NSEC_PER_SEC);
311 
312 	value = mc_readl(mc, MC_EMEM_ARB_CFG);
313 	value &= ~MC_EMEM_ARB_CFG_CYCLES_PER_UPDATE_MASK;
314 	value |= MC_EMEM_ARB_CFG_CYCLES_PER_UPDATE(tick);
315 	mc_writel(mc, value, MC_EMEM_ARB_CFG);
316 
317 	/* write latency allowance defaults */
318 	for (i = 0; i < mc->soc->num_clients; i++) {
319 		const struct tegra_mc_la *la = &mc->soc->clients[i].la;
320 		u32 value;
321 
322 		value = mc_readl(mc, la->reg);
323 		value &= ~(la->mask << la->shift);
324 		value |= (la->def & la->mask) << la->shift;
325 		mc_writel(mc, value, la->reg);
326 	}
327 
328 	/* latch new values */
329 	mc_writel(mc, MC_TIMING_UPDATE, MC_TIMING_CONTROL);
330 
331 	return 0;
332 }
333 
334 int tegra_mc_write_emem_configuration(struct tegra_mc *mc, unsigned long rate)
335 {
336 	unsigned int i;
337 	struct tegra_mc_timing *timing = NULL;
338 
339 	for (i = 0; i < mc->num_timings; i++) {
340 		if (mc->timings[i].rate == rate) {
341 			timing = &mc->timings[i];
342 			break;
343 		}
344 	}
345 
346 	if (!timing) {
347 		dev_err(mc->dev, "no memory timing registered for rate %lu\n",
348 			rate);
349 		return -EINVAL;
350 	}
351 
352 	for (i = 0; i < mc->soc->num_emem_regs; ++i)
353 		mc_writel(mc, timing->emem_data[i], mc->soc->emem_regs[i]);
354 
355 	return 0;
356 }
357 EXPORT_SYMBOL_GPL(tegra_mc_write_emem_configuration);
358 
359 unsigned int tegra_mc_get_emem_device_count(struct tegra_mc *mc)
360 {
361 	u8 dram_count;
362 
363 	dram_count = mc_readl(mc, MC_EMEM_ADR_CFG);
364 	dram_count &= MC_EMEM_ADR_CFG_EMEM_NUMDEV;
365 	dram_count++;
366 
367 	return dram_count;
368 }
369 EXPORT_SYMBOL_GPL(tegra_mc_get_emem_device_count);
370 
371 static int load_one_timing(struct tegra_mc *mc,
372 			   struct tegra_mc_timing *timing,
373 			   struct device_node *node)
374 {
375 	int err;
376 	u32 tmp;
377 
378 	err = of_property_read_u32(node, "clock-frequency", &tmp);
379 	if (err) {
380 		dev_err(mc->dev,
381 			"timing %pOFn: failed to read rate\n", node);
382 		return err;
383 	}
384 
385 	timing->rate = tmp;
386 	timing->emem_data = devm_kcalloc(mc->dev, mc->soc->num_emem_regs,
387 					 sizeof(u32), GFP_KERNEL);
388 	if (!timing->emem_data)
389 		return -ENOMEM;
390 
391 	err = of_property_read_u32_array(node, "nvidia,emem-configuration",
392 					 timing->emem_data,
393 					 mc->soc->num_emem_regs);
394 	if (err) {
395 		dev_err(mc->dev,
396 			"timing %pOFn: failed to read EMEM configuration\n",
397 			node);
398 		return err;
399 	}
400 
401 	return 0;
402 }
403 
404 static int load_timings(struct tegra_mc *mc, struct device_node *node)
405 {
406 	struct device_node *child;
407 	struct tegra_mc_timing *timing;
408 	int child_count = of_get_child_count(node);
409 	int i = 0, err;
410 
411 	mc->timings = devm_kcalloc(mc->dev, child_count, sizeof(*timing),
412 				   GFP_KERNEL);
413 	if (!mc->timings)
414 		return -ENOMEM;
415 
416 	mc->num_timings = child_count;
417 
418 	for_each_child_of_node(node, child) {
419 		timing = &mc->timings[i++];
420 
421 		err = load_one_timing(mc, timing, child);
422 		if (err) {
423 			of_node_put(child);
424 			return err;
425 		}
426 	}
427 
428 	return 0;
429 }
430 
431 static int tegra_mc_setup_timings(struct tegra_mc *mc)
432 {
433 	struct device_node *node;
434 	u32 ram_code, node_ram_code;
435 	int err;
436 
437 	ram_code = tegra_read_ram_code();
438 
439 	mc->num_timings = 0;
440 
441 	for_each_child_of_node(mc->dev->of_node, node) {
442 		err = of_property_read_u32(node, "nvidia,ram-code",
443 					   &node_ram_code);
444 		if (err || (node_ram_code != ram_code))
445 			continue;
446 
447 		err = load_timings(mc, node);
448 		of_node_put(node);
449 		if (err)
450 			return err;
451 		break;
452 	}
453 
454 	if (mc->num_timings == 0)
455 		dev_warn(mc->dev,
456 			 "no memory timings for RAM code %u registered\n",
457 			 ram_code);
458 
459 	return 0;
460 }
461 
462 static const char *const status_names[32] = {
463 	[ 1] = "External interrupt",
464 	[ 6] = "EMEM address decode error",
465 	[ 7] = "GART page fault",
466 	[ 8] = "Security violation",
467 	[ 9] = "EMEM arbitration error",
468 	[10] = "Page fault",
469 	[11] = "Invalid APB ASID update",
470 	[12] = "VPR violation",
471 	[13] = "Secure carveout violation",
472 	[16] = "MTS carveout violation",
473 };
474 
475 static const char *const error_names[8] = {
476 	[2] = "EMEM decode error",
477 	[3] = "TrustZone violation",
478 	[4] = "Carveout violation",
479 	[6] = "SMMU translation error",
480 };
481 
482 static irqreturn_t tegra_mc_irq(int irq, void *data)
483 {
484 	struct tegra_mc *mc = data;
485 	unsigned long status;
486 	unsigned int bit;
487 
488 	/* mask all interrupts to avoid flooding */
489 	status = mc_readl(mc, MC_INTSTATUS) & mc->soc->intmask;
490 	if (!status)
491 		return IRQ_NONE;
492 
493 	for_each_set_bit(bit, &status, 32) {
494 		const char *error = status_names[bit] ?: "unknown";
495 		const char *client = "unknown", *desc;
496 		const char *direction, *secure;
497 		phys_addr_t addr = 0;
498 		unsigned int i;
499 		char perm[7];
500 		u8 id, type;
501 		u32 value;
502 
503 		value = mc_readl(mc, MC_ERR_STATUS);
504 
505 #ifdef CONFIG_PHYS_ADDR_T_64BIT
506 		if (mc->soc->num_address_bits > 32) {
507 			addr = ((value >> MC_ERR_STATUS_ADR_HI_SHIFT) &
508 				MC_ERR_STATUS_ADR_HI_MASK);
509 			addr <<= 32;
510 		}
511 #endif
512 
513 		if (value & MC_ERR_STATUS_RW)
514 			direction = "write";
515 		else
516 			direction = "read";
517 
518 		if (value & MC_ERR_STATUS_SECURITY)
519 			secure = "secure ";
520 		else
521 			secure = "";
522 
523 		id = value & mc->soc->client_id_mask;
524 
525 		for (i = 0; i < mc->soc->num_clients; i++) {
526 			if (mc->soc->clients[i].id == id) {
527 				client = mc->soc->clients[i].name;
528 				break;
529 			}
530 		}
531 
532 		type = (value & MC_ERR_STATUS_TYPE_MASK) >>
533 		       MC_ERR_STATUS_TYPE_SHIFT;
534 		desc = error_names[type];
535 
536 		switch (value & MC_ERR_STATUS_TYPE_MASK) {
537 		case MC_ERR_STATUS_TYPE_INVALID_SMMU_PAGE:
538 			perm[0] = ' ';
539 			perm[1] = '[';
540 
541 			if (value & MC_ERR_STATUS_READABLE)
542 				perm[2] = 'R';
543 			else
544 				perm[2] = '-';
545 
546 			if (value & MC_ERR_STATUS_WRITABLE)
547 				perm[3] = 'W';
548 			else
549 				perm[3] = '-';
550 
551 			if (value & MC_ERR_STATUS_NONSECURE)
552 				perm[4] = '-';
553 			else
554 				perm[4] = 'S';
555 
556 			perm[5] = ']';
557 			perm[6] = '\0';
558 			break;
559 
560 		default:
561 			perm[0] = '\0';
562 			break;
563 		}
564 
565 		value = mc_readl(mc, MC_ERR_ADR);
566 		addr |= value;
567 
568 		dev_err_ratelimited(mc->dev, "%s: %s%s @%pa: %s (%s%s)\n",
569 				    client, secure, direction, &addr, error,
570 				    desc, perm);
571 	}
572 
573 	/* clear interrupts */
574 	mc_writel(mc, status, MC_INTSTATUS);
575 
576 	return IRQ_HANDLED;
577 }
578 
579 static __maybe_unused irqreturn_t tegra20_mc_irq(int irq, void *data)
580 {
581 	struct tegra_mc *mc = data;
582 	unsigned long status;
583 	unsigned int bit;
584 
585 	/* mask all interrupts to avoid flooding */
586 	status = mc_readl(mc, MC_INTSTATUS) & mc->soc->intmask;
587 	if (!status)
588 		return IRQ_NONE;
589 
590 	for_each_set_bit(bit, &status, 32) {
591 		const char *direction = "read", *secure = "";
592 		const char *error = status_names[bit];
593 		const char *client, *desc;
594 		phys_addr_t addr;
595 		u32 value, reg;
596 		u8 id, type;
597 
598 		switch (BIT(bit)) {
599 		case MC_INT_DECERR_EMEM:
600 			reg = MC_DECERR_EMEM_OTHERS_STATUS;
601 			value = mc_readl(mc, reg);
602 
603 			id = value & mc->soc->client_id_mask;
604 			desc = error_names[2];
605 
606 			if (value & BIT(31))
607 				direction = "write";
608 			break;
609 
610 		case MC_INT_INVALID_GART_PAGE:
611 			reg = MC_GART_ERROR_REQ;
612 			value = mc_readl(mc, reg);
613 
614 			id = (value >> 1) & mc->soc->client_id_mask;
615 			desc = error_names[2];
616 
617 			if (value & BIT(0))
618 				direction = "write";
619 			break;
620 
621 		case MC_INT_SECURITY_VIOLATION:
622 			reg = MC_SECURITY_VIOLATION_STATUS;
623 			value = mc_readl(mc, reg);
624 
625 			id = value & mc->soc->client_id_mask;
626 			type = (value & BIT(30)) ? 4 : 3;
627 			desc = error_names[type];
628 			secure = "secure ";
629 
630 			if (value & BIT(31))
631 				direction = "write";
632 			break;
633 
634 		default:
635 			continue;
636 		}
637 
638 		client = mc->soc->clients[id].name;
639 		addr = mc_readl(mc, reg + sizeof(u32));
640 
641 		dev_err_ratelimited(mc->dev, "%s: %s%s @%pa: %s (%s)\n",
642 				    client, secure, direction, &addr, error,
643 				    desc);
644 	}
645 
646 	/* clear interrupts */
647 	mc_writel(mc, status, MC_INTSTATUS);
648 
649 	return IRQ_HANDLED;
650 }
651 
652 /*
653  * Memory Controller (MC) has few Memory Clients that are issuing memory
654  * bandwidth allocation requests to the MC interconnect provider. The MC
655  * provider aggregates the requests and then sends the aggregated request
656  * up to the External Memory Controller (EMC) interconnect provider which
657  * re-configures hardware interface to External Memory (EMEM) in accordance
658  * to the required bandwidth. Each MC interconnect node represents an
659  * individual Memory Client.
660  *
661  * Memory interconnect topology:
662  *
663  *               +----+
664  * +--------+    |    |
665  * | TEXSRD +--->+    |
666  * +--------+    |    |
667  *               |    |    +-----+    +------+
668  *    ...        | MC +--->+ EMC +--->+ EMEM |
669  *               |    |    +-----+    +------+
670  * +--------+    |    |
671  * | DISP.. +--->+    |
672  * +--------+    |    |
673  *               +----+
674  */
675 static int tegra_mc_interconnect_setup(struct tegra_mc *mc)
676 {
677 	struct icc_node *node;
678 	unsigned int i;
679 	int err;
680 
681 	/* older device-trees don't have interconnect properties */
682 	if (!device_property_present(mc->dev, "#interconnect-cells") ||
683 	    !mc->soc->icc_ops)
684 		return 0;
685 
686 	mc->provider.dev = mc->dev;
687 	mc->provider.data = &mc->provider;
688 	mc->provider.set = mc->soc->icc_ops->set;
689 	mc->provider.aggregate = mc->soc->icc_ops->aggregate;
690 	mc->provider.xlate_extended = mc->soc->icc_ops->xlate_extended;
691 
692 	err = icc_provider_add(&mc->provider);
693 	if (err)
694 		return err;
695 
696 	/* create Memory Controller node */
697 	node = icc_node_create(TEGRA_ICC_MC);
698 	if (IS_ERR(node)) {
699 		err = PTR_ERR(node);
700 		goto del_provider;
701 	}
702 
703 	node->name = "Memory Controller";
704 	icc_node_add(node, &mc->provider);
705 
706 	/* link Memory Controller to External Memory Controller */
707 	err = icc_link_create(node, TEGRA_ICC_EMC);
708 	if (err)
709 		goto remove_nodes;
710 
711 	for (i = 0; i < mc->soc->num_clients; i++) {
712 		/* create MC client node */
713 		node = icc_node_create(mc->soc->clients[i].id);
714 		if (IS_ERR(node)) {
715 			err = PTR_ERR(node);
716 			goto remove_nodes;
717 		}
718 
719 		node->name = mc->soc->clients[i].name;
720 		icc_node_add(node, &mc->provider);
721 
722 		/* link Memory Client to Memory Controller */
723 		err = icc_link_create(node, TEGRA_ICC_MC);
724 		if (err)
725 			goto remove_nodes;
726 	}
727 
728 	/*
729 	 * MC driver is registered too early, so early that generic driver
730 	 * syncing doesn't work for the MC. But it doesn't really matter
731 	 * since syncing works for the EMC drivers, hence we can sync the
732 	 * MC driver by ourselves and then EMC will complete syncing of
733 	 * the whole ICC state.
734 	 */
735 	icc_sync_state(mc->dev);
736 
737 	return 0;
738 
739 remove_nodes:
740 	icc_nodes_remove(&mc->provider);
741 del_provider:
742 	icc_provider_del(&mc->provider);
743 
744 	return err;
745 }
746 
747 static int tegra_mc_probe(struct platform_device *pdev)
748 {
749 	struct resource *res;
750 	struct tegra_mc *mc;
751 	void *isr;
752 	u64 mask;
753 	int err;
754 
755 	mc = devm_kzalloc(&pdev->dev, sizeof(*mc), GFP_KERNEL);
756 	if (!mc)
757 		return -ENOMEM;
758 
759 	platform_set_drvdata(pdev, mc);
760 	spin_lock_init(&mc->lock);
761 	mc->soc = of_device_get_match_data(&pdev->dev);
762 	mc->dev = &pdev->dev;
763 
764 	mask = DMA_BIT_MASK(mc->soc->num_address_bits);
765 
766 	err = dma_coerce_mask_and_coherent(&pdev->dev, mask);
767 	if (err < 0) {
768 		dev_err(&pdev->dev, "failed to set DMA mask: %d\n", err);
769 		return err;
770 	}
771 
772 	/* length of MC tick in nanoseconds */
773 	mc->tick = 30;
774 
775 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
776 	mc->regs = devm_ioremap_resource(&pdev->dev, res);
777 	if (IS_ERR(mc->regs))
778 		return PTR_ERR(mc->regs);
779 
780 	mc->clk = devm_clk_get(&pdev->dev, "mc");
781 	if (IS_ERR(mc->clk)) {
782 		dev_err(&pdev->dev, "failed to get MC clock: %ld\n",
783 			PTR_ERR(mc->clk));
784 		return PTR_ERR(mc->clk);
785 	}
786 
787 #ifdef CONFIG_ARCH_TEGRA_2x_SOC
788 	if (mc->soc == &tegra20_mc_soc) {
789 		isr = tegra20_mc_irq;
790 	} else
791 #endif
792 	{
793 		/* ensure that debug features are disabled */
794 		mc_writel(mc, 0x00000000, MC_TIMING_CONTROL_DBG);
795 
796 		err = tegra_mc_setup_latency_allowance(mc);
797 		if (err < 0) {
798 			dev_err(&pdev->dev,
799 				"failed to setup latency allowance: %d\n",
800 				err);
801 			return err;
802 		}
803 
804 		isr = tegra_mc_irq;
805 
806 		err = tegra_mc_setup_timings(mc);
807 		if (err < 0) {
808 			dev_err(&pdev->dev, "failed to setup timings: %d\n",
809 				err);
810 			return err;
811 		}
812 	}
813 
814 	mc->irq = platform_get_irq(pdev, 0);
815 	if (mc->irq < 0)
816 		return mc->irq;
817 
818 	WARN(!mc->soc->client_id_mask, "missing client ID mask for this SoC\n");
819 
820 	mc_writel(mc, mc->soc->intmask, MC_INTMASK);
821 
822 	err = devm_request_irq(&pdev->dev, mc->irq, isr, 0,
823 			       dev_name(&pdev->dev), mc);
824 	if (err < 0) {
825 		dev_err(&pdev->dev, "failed to request IRQ#%u: %d\n", mc->irq,
826 			err);
827 		return err;
828 	}
829 
830 	err = tegra_mc_reset_setup(mc);
831 	if (err < 0)
832 		dev_err(&pdev->dev, "failed to register reset controller: %d\n",
833 			err);
834 
835 	err = tegra_mc_interconnect_setup(mc);
836 	if (err < 0)
837 		dev_err(&pdev->dev, "failed to initialize interconnect: %d\n",
838 			err);
839 
840 	if (IS_ENABLED(CONFIG_TEGRA_IOMMU_SMMU) && mc->soc->smmu) {
841 		mc->smmu = tegra_smmu_probe(&pdev->dev, mc->soc->smmu, mc);
842 		if (IS_ERR(mc->smmu)) {
843 			dev_err(&pdev->dev, "failed to probe SMMU: %ld\n",
844 				PTR_ERR(mc->smmu));
845 			mc->smmu = NULL;
846 		}
847 	}
848 
849 	if (IS_ENABLED(CONFIG_TEGRA_IOMMU_GART) && !mc->soc->smmu) {
850 		mc->gart = tegra_gart_probe(&pdev->dev, mc);
851 		if (IS_ERR(mc->gart)) {
852 			dev_err(&pdev->dev, "failed to probe GART: %ld\n",
853 				PTR_ERR(mc->gart));
854 			mc->gart = NULL;
855 		}
856 	}
857 
858 	return 0;
859 }
860 
861 static int tegra_mc_suspend(struct device *dev)
862 {
863 	struct tegra_mc *mc = dev_get_drvdata(dev);
864 	int err;
865 
866 	if (IS_ENABLED(CONFIG_TEGRA_IOMMU_GART) && mc->gart) {
867 		err = tegra_gart_suspend(mc->gart);
868 		if (err)
869 			return err;
870 	}
871 
872 	return 0;
873 }
874 
875 static int tegra_mc_resume(struct device *dev)
876 {
877 	struct tegra_mc *mc = dev_get_drvdata(dev);
878 	int err;
879 
880 	if (IS_ENABLED(CONFIG_TEGRA_IOMMU_GART) && mc->gart) {
881 		err = tegra_gart_resume(mc->gart);
882 		if (err)
883 			return err;
884 	}
885 
886 	return 0;
887 }
888 
889 static const struct dev_pm_ops tegra_mc_pm_ops = {
890 	.suspend = tegra_mc_suspend,
891 	.resume = tegra_mc_resume,
892 };
893 
894 static struct platform_driver tegra_mc_driver = {
895 	.driver = {
896 		.name = "tegra-mc",
897 		.of_match_table = tegra_mc_of_match,
898 		.pm = &tegra_mc_pm_ops,
899 		.suppress_bind_attrs = true,
900 	},
901 	.prevent_deferred_probe = true,
902 	.probe = tegra_mc_probe,
903 };
904 
905 static int tegra_mc_init(void)
906 {
907 	return platform_driver_register(&tegra_mc_driver);
908 }
909 arch_initcall(tegra_mc_init);
910 
911 MODULE_AUTHOR("Thierry Reding <treding@nvidia.com>");
912 MODULE_DESCRIPTION("NVIDIA Tegra Memory Controller driver");
913 MODULE_LICENSE("GPL v2");
914