xref: /openbmc/linux/drivers/memory/tegra/mc.c (revision 96ac6d43)
1 /*
2  * Copyright (C) 2014 NVIDIA CORPORATION.  All rights reserved.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  */
8 
9 #include <linux/clk.h>
10 #include <linux/delay.h>
11 #include <linux/interrupt.h>
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/of.h>
15 #include <linux/of_device.h>
16 #include <linux/platform_device.h>
17 #include <linux/slab.h>
18 #include <linux/sort.h>
19 
20 #include <soc/tegra/fuse.h>
21 
22 #include "mc.h"
23 
24 #define MC_INTSTATUS 0x000
25 
26 #define MC_INTMASK 0x004
27 
28 #define MC_ERR_STATUS 0x08
29 #define  MC_ERR_STATUS_TYPE_SHIFT 28
30 #define  MC_ERR_STATUS_TYPE_INVALID_SMMU_PAGE (6 << MC_ERR_STATUS_TYPE_SHIFT)
31 #define  MC_ERR_STATUS_TYPE_MASK (0x7 << MC_ERR_STATUS_TYPE_SHIFT)
32 #define  MC_ERR_STATUS_READABLE (1 << 27)
33 #define  MC_ERR_STATUS_WRITABLE (1 << 26)
34 #define  MC_ERR_STATUS_NONSECURE (1 << 25)
35 #define  MC_ERR_STATUS_ADR_HI_SHIFT 20
36 #define  MC_ERR_STATUS_ADR_HI_MASK 0x3
37 #define  MC_ERR_STATUS_SECURITY (1 << 17)
38 #define  MC_ERR_STATUS_RW (1 << 16)
39 
40 #define MC_ERR_ADR 0x0c
41 
42 #define MC_GART_ERROR_REQ		0x30
43 #define MC_DECERR_EMEM_OTHERS_STATUS	0x58
44 #define MC_SECURITY_VIOLATION_STATUS	0x74
45 
46 #define MC_EMEM_ARB_CFG 0x90
47 #define  MC_EMEM_ARB_CFG_CYCLES_PER_UPDATE(x)	(((x) & 0x1ff) << 0)
48 #define  MC_EMEM_ARB_CFG_CYCLES_PER_UPDATE_MASK	0x1ff
49 #define MC_EMEM_ARB_MISC0 0xd8
50 
51 #define MC_EMEM_ADR_CFG 0x54
52 #define MC_EMEM_ADR_CFG_EMEM_NUMDEV BIT(0)
53 
54 #define MC_TIMING_CONTROL		0xfc
55 #define MC_TIMING_UPDATE		BIT(0)
56 
57 static const struct of_device_id tegra_mc_of_match[] = {
58 #ifdef CONFIG_ARCH_TEGRA_2x_SOC
59 	{ .compatible = "nvidia,tegra20-mc-gart", .data = &tegra20_mc_soc },
60 #endif
61 #ifdef CONFIG_ARCH_TEGRA_3x_SOC
62 	{ .compatible = "nvidia,tegra30-mc", .data = &tegra30_mc_soc },
63 #endif
64 #ifdef CONFIG_ARCH_TEGRA_114_SOC
65 	{ .compatible = "nvidia,tegra114-mc", .data = &tegra114_mc_soc },
66 #endif
67 #ifdef CONFIG_ARCH_TEGRA_124_SOC
68 	{ .compatible = "nvidia,tegra124-mc", .data = &tegra124_mc_soc },
69 #endif
70 #ifdef CONFIG_ARCH_TEGRA_132_SOC
71 	{ .compatible = "nvidia,tegra132-mc", .data = &tegra132_mc_soc },
72 #endif
73 #ifdef CONFIG_ARCH_TEGRA_210_SOC
74 	{ .compatible = "nvidia,tegra210-mc", .data = &tegra210_mc_soc },
75 #endif
76 	{ }
77 };
78 MODULE_DEVICE_TABLE(of, tegra_mc_of_match);
79 
80 static int tegra_mc_block_dma_common(struct tegra_mc *mc,
81 				     const struct tegra_mc_reset *rst)
82 {
83 	unsigned long flags;
84 	u32 value;
85 
86 	spin_lock_irqsave(&mc->lock, flags);
87 
88 	value = mc_readl(mc, rst->control) | BIT(rst->bit);
89 	mc_writel(mc, value, rst->control);
90 
91 	spin_unlock_irqrestore(&mc->lock, flags);
92 
93 	return 0;
94 }
95 
96 static bool tegra_mc_dma_idling_common(struct tegra_mc *mc,
97 				       const struct tegra_mc_reset *rst)
98 {
99 	return (mc_readl(mc, rst->status) & BIT(rst->bit)) != 0;
100 }
101 
102 static int tegra_mc_unblock_dma_common(struct tegra_mc *mc,
103 				       const struct tegra_mc_reset *rst)
104 {
105 	unsigned long flags;
106 	u32 value;
107 
108 	spin_lock_irqsave(&mc->lock, flags);
109 
110 	value = mc_readl(mc, rst->control) & ~BIT(rst->bit);
111 	mc_writel(mc, value, rst->control);
112 
113 	spin_unlock_irqrestore(&mc->lock, flags);
114 
115 	return 0;
116 }
117 
118 static int tegra_mc_reset_status_common(struct tegra_mc *mc,
119 					const struct tegra_mc_reset *rst)
120 {
121 	return (mc_readl(mc, rst->control) & BIT(rst->bit)) != 0;
122 }
123 
124 const struct tegra_mc_reset_ops tegra_mc_reset_ops_common = {
125 	.block_dma = tegra_mc_block_dma_common,
126 	.dma_idling = tegra_mc_dma_idling_common,
127 	.unblock_dma = tegra_mc_unblock_dma_common,
128 	.reset_status = tegra_mc_reset_status_common,
129 };
130 
131 static inline struct tegra_mc *reset_to_mc(struct reset_controller_dev *rcdev)
132 {
133 	return container_of(rcdev, struct tegra_mc, reset);
134 }
135 
136 static const struct tegra_mc_reset *tegra_mc_reset_find(struct tegra_mc *mc,
137 							unsigned long id)
138 {
139 	unsigned int i;
140 
141 	for (i = 0; i < mc->soc->num_resets; i++)
142 		if (mc->soc->resets[i].id == id)
143 			return &mc->soc->resets[i];
144 
145 	return NULL;
146 }
147 
148 static int tegra_mc_hotreset_assert(struct reset_controller_dev *rcdev,
149 				    unsigned long id)
150 {
151 	struct tegra_mc *mc = reset_to_mc(rcdev);
152 	const struct tegra_mc_reset_ops *rst_ops;
153 	const struct tegra_mc_reset *rst;
154 	int retries = 500;
155 	int err;
156 
157 	rst = tegra_mc_reset_find(mc, id);
158 	if (!rst)
159 		return -ENODEV;
160 
161 	rst_ops = mc->soc->reset_ops;
162 	if (!rst_ops)
163 		return -ENODEV;
164 
165 	if (rst_ops->block_dma) {
166 		/* block clients DMA requests */
167 		err = rst_ops->block_dma(mc, rst);
168 		if (err) {
169 			dev_err(mc->dev, "failed to block %s DMA: %d\n",
170 				rst->name, err);
171 			return err;
172 		}
173 	}
174 
175 	if (rst_ops->dma_idling) {
176 		/* wait for completion of the outstanding DMA requests */
177 		while (!rst_ops->dma_idling(mc, rst)) {
178 			if (!retries--) {
179 				dev_err(mc->dev, "failed to flush %s DMA\n",
180 					rst->name);
181 				return -EBUSY;
182 			}
183 
184 			usleep_range(10, 100);
185 		}
186 	}
187 
188 	if (rst_ops->hotreset_assert) {
189 		/* clear clients DMA requests sitting before arbitration */
190 		err = rst_ops->hotreset_assert(mc, rst);
191 		if (err) {
192 			dev_err(mc->dev, "failed to hot reset %s: %d\n",
193 				rst->name, err);
194 			return err;
195 		}
196 	}
197 
198 	return 0;
199 }
200 
201 static int tegra_mc_hotreset_deassert(struct reset_controller_dev *rcdev,
202 				      unsigned long id)
203 {
204 	struct tegra_mc *mc = reset_to_mc(rcdev);
205 	const struct tegra_mc_reset_ops *rst_ops;
206 	const struct tegra_mc_reset *rst;
207 	int err;
208 
209 	rst = tegra_mc_reset_find(mc, id);
210 	if (!rst)
211 		return -ENODEV;
212 
213 	rst_ops = mc->soc->reset_ops;
214 	if (!rst_ops)
215 		return -ENODEV;
216 
217 	if (rst_ops->hotreset_deassert) {
218 		/* take out client from hot reset */
219 		err = rst_ops->hotreset_deassert(mc, rst);
220 		if (err) {
221 			dev_err(mc->dev, "failed to deassert hot reset %s: %d\n",
222 				rst->name, err);
223 			return err;
224 		}
225 	}
226 
227 	if (rst_ops->unblock_dma) {
228 		/* allow new DMA requests to proceed to arbitration */
229 		err = rst_ops->unblock_dma(mc, rst);
230 		if (err) {
231 			dev_err(mc->dev, "failed to unblock %s DMA : %d\n",
232 				rst->name, err);
233 			return err;
234 		}
235 	}
236 
237 	return 0;
238 }
239 
240 static int tegra_mc_hotreset_status(struct reset_controller_dev *rcdev,
241 				    unsigned long id)
242 {
243 	struct tegra_mc *mc = reset_to_mc(rcdev);
244 	const struct tegra_mc_reset_ops *rst_ops;
245 	const struct tegra_mc_reset *rst;
246 
247 	rst = tegra_mc_reset_find(mc, id);
248 	if (!rst)
249 		return -ENODEV;
250 
251 	rst_ops = mc->soc->reset_ops;
252 	if (!rst_ops)
253 		return -ENODEV;
254 
255 	return rst_ops->reset_status(mc, rst);
256 }
257 
258 static const struct reset_control_ops tegra_mc_reset_ops = {
259 	.assert = tegra_mc_hotreset_assert,
260 	.deassert = tegra_mc_hotreset_deassert,
261 	.status = tegra_mc_hotreset_status,
262 };
263 
264 static int tegra_mc_reset_setup(struct tegra_mc *mc)
265 {
266 	int err;
267 
268 	mc->reset.ops = &tegra_mc_reset_ops;
269 	mc->reset.owner = THIS_MODULE;
270 	mc->reset.of_node = mc->dev->of_node;
271 	mc->reset.of_reset_n_cells = 1;
272 	mc->reset.nr_resets = mc->soc->num_resets;
273 
274 	err = reset_controller_register(&mc->reset);
275 	if (err < 0)
276 		return err;
277 
278 	return 0;
279 }
280 
281 static int tegra_mc_setup_latency_allowance(struct tegra_mc *mc)
282 {
283 	unsigned long long tick;
284 	unsigned int i;
285 	u32 value;
286 
287 	/* compute the number of MC clock cycles per tick */
288 	tick = (unsigned long long)mc->tick * clk_get_rate(mc->clk);
289 	do_div(tick, NSEC_PER_SEC);
290 
291 	value = mc_readl(mc, MC_EMEM_ARB_CFG);
292 	value &= ~MC_EMEM_ARB_CFG_CYCLES_PER_UPDATE_MASK;
293 	value |= MC_EMEM_ARB_CFG_CYCLES_PER_UPDATE(tick);
294 	mc_writel(mc, value, MC_EMEM_ARB_CFG);
295 
296 	/* write latency allowance defaults */
297 	for (i = 0; i < mc->soc->num_clients; i++) {
298 		const struct tegra_mc_la *la = &mc->soc->clients[i].la;
299 		u32 value;
300 
301 		value = mc_readl(mc, la->reg);
302 		value &= ~(la->mask << la->shift);
303 		value |= (la->def & la->mask) << la->shift;
304 		mc_writel(mc, value, la->reg);
305 	}
306 
307 	/* latch new values */
308 	mc_writel(mc, MC_TIMING_UPDATE, MC_TIMING_CONTROL);
309 
310 	return 0;
311 }
312 
313 void tegra_mc_write_emem_configuration(struct tegra_mc *mc, unsigned long rate)
314 {
315 	unsigned int i;
316 	struct tegra_mc_timing *timing = NULL;
317 
318 	for (i = 0; i < mc->num_timings; i++) {
319 		if (mc->timings[i].rate == rate) {
320 			timing = &mc->timings[i];
321 			break;
322 		}
323 	}
324 
325 	if (!timing) {
326 		dev_err(mc->dev, "no memory timing registered for rate %lu\n",
327 			rate);
328 		return;
329 	}
330 
331 	for (i = 0; i < mc->soc->num_emem_regs; ++i)
332 		mc_writel(mc, timing->emem_data[i], mc->soc->emem_regs[i]);
333 }
334 
335 unsigned int tegra_mc_get_emem_device_count(struct tegra_mc *mc)
336 {
337 	u8 dram_count;
338 
339 	dram_count = mc_readl(mc, MC_EMEM_ADR_CFG);
340 	dram_count &= MC_EMEM_ADR_CFG_EMEM_NUMDEV;
341 	dram_count++;
342 
343 	return dram_count;
344 }
345 
346 static int load_one_timing(struct tegra_mc *mc,
347 			   struct tegra_mc_timing *timing,
348 			   struct device_node *node)
349 {
350 	int err;
351 	u32 tmp;
352 
353 	err = of_property_read_u32(node, "clock-frequency", &tmp);
354 	if (err) {
355 		dev_err(mc->dev,
356 			"timing %pOFn: failed to read rate\n", node);
357 		return err;
358 	}
359 
360 	timing->rate = tmp;
361 	timing->emem_data = devm_kcalloc(mc->dev, mc->soc->num_emem_regs,
362 					 sizeof(u32), GFP_KERNEL);
363 	if (!timing->emem_data)
364 		return -ENOMEM;
365 
366 	err = of_property_read_u32_array(node, "nvidia,emem-configuration",
367 					 timing->emem_data,
368 					 mc->soc->num_emem_regs);
369 	if (err) {
370 		dev_err(mc->dev,
371 			"timing %pOFn: failed to read EMEM configuration\n",
372 			node);
373 		return err;
374 	}
375 
376 	return 0;
377 }
378 
379 static int load_timings(struct tegra_mc *mc, struct device_node *node)
380 {
381 	struct device_node *child;
382 	struct tegra_mc_timing *timing;
383 	int child_count = of_get_child_count(node);
384 	int i = 0, err;
385 
386 	mc->timings = devm_kcalloc(mc->dev, child_count, sizeof(*timing),
387 				   GFP_KERNEL);
388 	if (!mc->timings)
389 		return -ENOMEM;
390 
391 	mc->num_timings = child_count;
392 
393 	for_each_child_of_node(node, child) {
394 		timing = &mc->timings[i++];
395 
396 		err = load_one_timing(mc, timing, child);
397 		if (err) {
398 			of_node_put(child);
399 			return err;
400 		}
401 	}
402 
403 	return 0;
404 }
405 
406 static int tegra_mc_setup_timings(struct tegra_mc *mc)
407 {
408 	struct device_node *node;
409 	u32 ram_code, node_ram_code;
410 	int err;
411 
412 	ram_code = tegra_read_ram_code();
413 
414 	mc->num_timings = 0;
415 
416 	for_each_child_of_node(mc->dev->of_node, node) {
417 		err = of_property_read_u32(node, "nvidia,ram-code",
418 					   &node_ram_code);
419 		if (err || (node_ram_code != ram_code))
420 			continue;
421 
422 		err = load_timings(mc, node);
423 		of_node_put(node);
424 		if (err)
425 			return err;
426 		break;
427 	}
428 
429 	if (mc->num_timings == 0)
430 		dev_warn(mc->dev,
431 			 "no memory timings for RAM code %u registered\n",
432 			 ram_code);
433 
434 	return 0;
435 }
436 
437 static const char *const status_names[32] = {
438 	[ 1] = "External interrupt",
439 	[ 6] = "EMEM address decode error",
440 	[ 7] = "GART page fault",
441 	[ 8] = "Security violation",
442 	[ 9] = "EMEM arbitration error",
443 	[10] = "Page fault",
444 	[11] = "Invalid APB ASID update",
445 	[12] = "VPR violation",
446 	[13] = "Secure carveout violation",
447 	[16] = "MTS carveout violation",
448 };
449 
450 static const char *const error_names[8] = {
451 	[2] = "EMEM decode error",
452 	[3] = "TrustZone violation",
453 	[4] = "Carveout violation",
454 	[6] = "SMMU translation error",
455 };
456 
457 static irqreturn_t tegra_mc_irq(int irq, void *data)
458 {
459 	struct tegra_mc *mc = data;
460 	unsigned long status;
461 	unsigned int bit;
462 
463 	/* mask all interrupts to avoid flooding */
464 	status = mc_readl(mc, MC_INTSTATUS) & mc->soc->intmask;
465 	if (!status)
466 		return IRQ_NONE;
467 
468 	for_each_set_bit(bit, &status, 32) {
469 		const char *error = status_names[bit] ?: "unknown";
470 		const char *client = "unknown", *desc;
471 		const char *direction, *secure;
472 		phys_addr_t addr = 0;
473 		unsigned int i;
474 		char perm[7];
475 		u8 id, type;
476 		u32 value;
477 
478 		value = mc_readl(mc, MC_ERR_STATUS);
479 
480 #ifdef CONFIG_PHYS_ADDR_T_64BIT
481 		if (mc->soc->num_address_bits > 32) {
482 			addr = ((value >> MC_ERR_STATUS_ADR_HI_SHIFT) &
483 				MC_ERR_STATUS_ADR_HI_MASK);
484 			addr <<= 32;
485 		}
486 #endif
487 
488 		if (value & MC_ERR_STATUS_RW)
489 			direction = "write";
490 		else
491 			direction = "read";
492 
493 		if (value & MC_ERR_STATUS_SECURITY)
494 			secure = "secure ";
495 		else
496 			secure = "";
497 
498 		id = value & mc->soc->client_id_mask;
499 
500 		for (i = 0; i < mc->soc->num_clients; i++) {
501 			if (mc->soc->clients[i].id == id) {
502 				client = mc->soc->clients[i].name;
503 				break;
504 			}
505 		}
506 
507 		type = (value & MC_ERR_STATUS_TYPE_MASK) >>
508 		       MC_ERR_STATUS_TYPE_SHIFT;
509 		desc = error_names[type];
510 
511 		switch (value & MC_ERR_STATUS_TYPE_MASK) {
512 		case MC_ERR_STATUS_TYPE_INVALID_SMMU_PAGE:
513 			perm[0] = ' ';
514 			perm[1] = '[';
515 
516 			if (value & MC_ERR_STATUS_READABLE)
517 				perm[2] = 'R';
518 			else
519 				perm[2] = '-';
520 
521 			if (value & MC_ERR_STATUS_WRITABLE)
522 				perm[3] = 'W';
523 			else
524 				perm[3] = '-';
525 
526 			if (value & MC_ERR_STATUS_NONSECURE)
527 				perm[4] = '-';
528 			else
529 				perm[4] = 'S';
530 
531 			perm[5] = ']';
532 			perm[6] = '\0';
533 			break;
534 
535 		default:
536 			perm[0] = '\0';
537 			break;
538 		}
539 
540 		value = mc_readl(mc, MC_ERR_ADR);
541 		addr |= value;
542 
543 		dev_err_ratelimited(mc->dev, "%s: %s%s @%pa: %s (%s%s)\n",
544 				    client, secure, direction, &addr, error,
545 				    desc, perm);
546 	}
547 
548 	/* clear interrupts */
549 	mc_writel(mc, status, MC_INTSTATUS);
550 
551 	return IRQ_HANDLED;
552 }
553 
554 static __maybe_unused irqreturn_t tegra20_mc_irq(int irq, void *data)
555 {
556 	struct tegra_mc *mc = data;
557 	unsigned long status;
558 	unsigned int bit;
559 
560 	/* mask all interrupts to avoid flooding */
561 	status = mc_readl(mc, MC_INTSTATUS) & mc->soc->intmask;
562 	if (!status)
563 		return IRQ_NONE;
564 
565 	for_each_set_bit(bit, &status, 32) {
566 		const char *direction = "read", *secure = "";
567 		const char *error = status_names[bit];
568 		const char *client, *desc;
569 		phys_addr_t addr;
570 		u32 value, reg;
571 		u8 id, type;
572 
573 		switch (BIT(bit)) {
574 		case MC_INT_DECERR_EMEM:
575 			reg = MC_DECERR_EMEM_OTHERS_STATUS;
576 			value = mc_readl(mc, reg);
577 
578 			id = value & mc->soc->client_id_mask;
579 			desc = error_names[2];
580 
581 			if (value & BIT(31))
582 				direction = "write";
583 			break;
584 
585 		case MC_INT_INVALID_GART_PAGE:
586 			reg = MC_GART_ERROR_REQ;
587 			value = mc_readl(mc, reg);
588 
589 			id = (value >> 1) & mc->soc->client_id_mask;
590 			desc = error_names[2];
591 
592 			if (value & BIT(0))
593 				direction = "write";
594 			break;
595 
596 		case MC_INT_SECURITY_VIOLATION:
597 			reg = MC_SECURITY_VIOLATION_STATUS;
598 			value = mc_readl(mc, reg);
599 
600 			id = value & mc->soc->client_id_mask;
601 			type = (value & BIT(30)) ? 4 : 3;
602 			desc = error_names[type];
603 			secure = "secure ";
604 
605 			if (value & BIT(31))
606 				direction = "write";
607 			break;
608 
609 		default:
610 			continue;
611 		}
612 
613 		client = mc->soc->clients[id].name;
614 		addr = mc_readl(mc, reg + sizeof(u32));
615 
616 		dev_err_ratelimited(mc->dev, "%s: %s%s @%pa: %s (%s)\n",
617 				    client, secure, direction, &addr, error,
618 				    desc);
619 	}
620 
621 	/* clear interrupts */
622 	mc_writel(mc, status, MC_INTSTATUS);
623 
624 	return IRQ_HANDLED;
625 }
626 
627 static int tegra_mc_probe(struct platform_device *pdev)
628 {
629 	struct resource *res;
630 	struct tegra_mc *mc;
631 	void *isr;
632 	int err;
633 
634 	mc = devm_kzalloc(&pdev->dev, sizeof(*mc), GFP_KERNEL);
635 	if (!mc)
636 		return -ENOMEM;
637 
638 	platform_set_drvdata(pdev, mc);
639 	spin_lock_init(&mc->lock);
640 	mc->soc = of_device_get_match_data(&pdev->dev);
641 	mc->dev = &pdev->dev;
642 
643 	/* length of MC tick in nanoseconds */
644 	mc->tick = 30;
645 
646 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
647 	mc->regs = devm_ioremap_resource(&pdev->dev, res);
648 	if (IS_ERR(mc->regs))
649 		return PTR_ERR(mc->regs);
650 
651 	mc->clk = devm_clk_get(&pdev->dev, "mc");
652 	if (IS_ERR(mc->clk)) {
653 		dev_err(&pdev->dev, "failed to get MC clock: %ld\n",
654 			PTR_ERR(mc->clk));
655 		return PTR_ERR(mc->clk);
656 	}
657 
658 #ifdef CONFIG_ARCH_TEGRA_2x_SOC
659 	if (mc->soc == &tegra20_mc_soc) {
660 		isr = tegra20_mc_irq;
661 	} else
662 #endif
663 	{
664 		err = tegra_mc_setup_latency_allowance(mc);
665 		if (err < 0) {
666 			dev_err(&pdev->dev,
667 				"failed to setup latency allowance: %d\n",
668 				err);
669 			return err;
670 		}
671 
672 		isr = tegra_mc_irq;
673 
674 		err = tegra_mc_setup_timings(mc);
675 		if (err < 0) {
676 			dev_err(&pdev->dev, "failed to setup timings: %d\n",
677 				err);
678 			return err;
679 		}
680 	}
681 
682 	mc->irq = platform_get_irq(pdev, 0);
683 	if (mc->irq < 0) {
684 		dev_err(&pdev->dev, "interrupt not specified\n");
685 		return mc->irq;
686 	}
687 
688 	WARN(!mc->soc->client_id_mask, "missing client ID mask for this SoC\n");
689 
690 	mc_writel(mc, mc->soc->intmask, MC_INTMASK);
691 
692 	err = devm_request_irq(&pdev->dev, mc->irq, isr, 0,
693 			       dev_name(&pdev->dev), mc);
694 	if (err < 0) {
695 		dev_err(&pdev->dev, "failed to request IRQ#%u: %d\n", mc->irq,
696 			err);
697 		return err;
698 	}
699 
700 	err = tegra_mc_reset_setup(mc);
701 	if (err < 0)
702 		dev_err(&pdev->dev, "failed to register reset controller: %d\n",
703 			err);
704 
705 	if (IS_ENABLED(CONFIG_TEGRA_IOMMU_SMMU) && mc->soc->smmu) {
706 		mc->smmu = tegra_smmu_probe(&pdev->dev, mc->soc->smmu, mc);
707 		if (IS_ERR(mc->smmu)) {
708 			dev_err(&pdev->dev, "failed to probe SMMU: %ld\n",
709 				PTR_ERR(mc->smmu));
710 			mc->smmu = NULL;
711 		}
712 	}
713 
714 	if (IS_ENABLED(CONFIG_TEGRA_IOMMU_GART) && !mc->soc->smmu) {
715 		mc->gart = tegra_gart_probe(&pdev->dev, mc);
716 		if (IS_ERR(mc->gart)) {
717 			dev_err(&pdev->dev, "failed to probe GART: %ld\n",
718 				PTR_ERR(mc->gart));
719 			mc->gart = NULL;
720 		}
721 	}
722 
723 	return 0;
724 }
725 
726 static int tegra_mc_suspend(struct device *dev)
727 {
728 	struct tegra_mc *mc = dev_get_drvdata(dev);
729 	int err;
730 
731 	if (IS_ENABLED(CONFIG_TEGRA_IOMMU_GART) && mc->gart) {
732 		err = tegra_gart_suspend(mc->gart);
733 		if (err)
734 			return err;
735 	}
736 
737 	return 0;
738 }
739 
740 static int tegra_mc_resume(struct device *dev)
741 {
742 	struct tegra_mc *mc = dev_get_drvdata(dev);
743 	int err;
744 
745 	if (IS_ENABLED(CONFIG_TEGRA_IOMMU_GART) && mc->gart) {
746 		err = tegra_gart_resume(mc->gart);
747 		if (err)
748 			return err;
749 	}
750 
751 	return 0;
752 }
753 
754 static const struct dev_pm_ops tegra_mc_pm_ops = {
755 	.suspend = tegra_mc_suspend,
756 	.resume = tegra_mc_resume,
757 };
758 
759 static struct platform_driver tegra_mc_driver = {
760 	.driver = {
761 		.name = "tegra-mc",
762 		.of_match_table = tegra_mc_of_match,
763 		.pm = &tegra_mc_pm_ops,
764 		.suppress_bind_attrs = true,
765 	},
766 	.prevent_deferred_probe = true,
767 	.probe = tegra_mc_probe,
768 };
769 
770 static int tegra_mc_init(void)
771 {
772 	return platform_driver_register(&tegra_mc_driver);
773 }
774 arch_initcall(tegra_mc_init);
775 
776 MODULE_AUTHOR("Thierry Reding <treding@nvidia.com>");
777 MODULE_DESCRIPTION("NVIDIA Tegra Memory Controller driver");
778 MODULE_LICENSE("GPL v2");
779