aboutsummaryrefslogtreecommitdiff
path: root/drivers/iommu/mtk_iommu_v1.c
blob: a27ef570c328d194d3528e81a64ea4f986e31ca6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
/*
 * Copyright (c) 2015-2016 MediaTek Inc.
 * Author: Honghui Zhang <honghui.zhang@mediatek.com>
 *
 * Based on driver/iommu/mtk_iommu.c
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */
#include <linux/bootmem.h>
#include <linux/bug.h>
#include <linux/clk.h>
#include <linux/component.h>
#include <linux/device.h>
#include <linux/dma-iommu.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/iommu.h>
#include <linux/iopoll.h>
#include <linux/kmemleak.h>
#include <linux/list.h>
#include <linux/of_address.h>
#include <linux/of_iommu.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <asm/barrier.h>
#include <asm/dma-iommu.h>
#include <linux/module.h>
#include <dt-bindings/memory/mt2701-larb-port.h>
#include <soc/mediatek/smi.h>
#include "mtk_iommu.h"

#define REG_MMU_PT_BASE_ADDR			0x000

#define F_ALL_INVLD				0x2
#define F_MMU_INV_RANGE				0x1
#define F_INVLD_EN0				BIT(0)
#define F_INVLD_EN1				BIT(1)

#define F_MMU_FAULT_VA_MSK			0xfffff000
#define MTK_PROTECT_PA_ALIGN			128

#define REG_MMU_CTRL_REG			0x210
#define F_MMU_CTRL_COHERENT_EN			BIT(8)
#define REG_MMU_IVRP_PADDR			0x214
#define REG_MMU_INT_CONTROL			0x220
#define F_INT_TRANSLATION_FAULT			BIT(0)
#define F_INT_MAIN_MULTI_HIT_FAULT		BIT(1)
#define F_INT_INVALID_PA_FAULT			BIT(2)
#define F_INT_ENTRY_REPLACEMENT_FAULT		BIT(3)
#define F_INT_TABLE_WALK_FAULT			BIT(4)
#define F_INT_TLB_MISS_FAULT			BIT(5)
#define F_INT_PFH_DMA_FIFO_OVERFLOW		BIT(6)
#define F_INT_MISS_DMA_FIFO_OVERFLOW		BIT(7)

#define F_MMU_TF_PROTECT_SEL(prot)		(((prot) & 0x3) << 5)
#define F_INT_CLR_BIT				BIT(12)

#define REG_MMU_FAULT_ST			0x224
#define REG_MMU_FAULT_VA			0x228
#define REG_MMU_INVLD_PA			0x22C
#define REG_MMU_INT_ID				0x388
#define REG_MMU_INVALIDATE			0x5c0
#define REG_MMU_INVLD_START_A			0x5c4
#define REG_MMU_INVLD_END_A			0x5c8

#define REG_MMU_INV_SEL				0x5d8
#define REG_MMU_STANDARD_AXI_MODE		0x5e8

#define REG_MMU_DCM				0x5f0
#define F_MMU_DCM_ON				BIT(1)
#define REG_MMU_CPE_DONE			0x60c
#define F_DESC_VALID				0x2
#define F_DESC_NONSEC				BIT(3)
#define MT2701_M4U_TF_LARB(TF)			(6 - (((TF) >> 13) & 0x7))
#define MT2701_M4U_TF_PORT(TF)			(((TF) >> 8) & 0xF)
/* MTK generation one iommu HW only support 4K size mapping */
#define MT2701_IOMMU_PAGE_SHIFT			12
#define MT2701_IOMMU_PAGE_SIZE			(1UL << MT2701_IOMMU_PAGE_SHIFT)

/*
 * MTK m4u support 4GB iova address space, and only support 4K page
 * mapping. So the pagetable size should be exactly as 4M.
 */
#define M2701_IOMMU_PGT_SIZE			SZ_4M

struct mtk_iommu_domain {
	spinlock_t			pgtlock; /* lock for page table */
	struct iommu_domain		domain;
	u32				*pgt_va;
	dma_addr_t			pgt_pa;
	struct mtk_iommu_data		*data;
};

static struct mtk_iommu_domain *to_mtk_domain(struct iommu_domain *dom)
{
	return container_of(dom, struct mtk_iommu_domain, domain);
}

static const int mt2701_m4u_in_larb[] = {
	LARB0_PORT_OFFSET, LARB1_PORT_OFFSET,
	LARB2_PORT_OFFSET, LARB3_PORT_OFFSET
};

static inline int mt2701_m4u_to_larb(int id)
{
	int i;

	for (i = ARRAY_SIZE(mt2701_m4u_in_larb) - 1; i >= 0; i--)
		if ((id) >= mt2701_m4u_in_larb[i])
			return i;

	return 0;
}

static inline int mt2701_m4u_to_port(int id)
{
	int larb = mt2701_m4u_to_larb(id);

	return id - mt2701_m4u_in_larb[larb];
}

static void mtk_iommu_tlb_flush_all(struct mtk_iommu_data *data)
{
	writel_relaxed(F_INVLD_EN1 | F_INVLD_EN0,
			data->base + REG_MMU_INV_SEL);
	writel_relaxed(F_ALL_INVLD, data->base + REG_MMU_INVALIDATE);
	wmb(); /* Make sure the tlb flush all done */
}

static void mtk_iommu_tlb_flush_range(struct mtk_iommu_data *data,
				unsigned long iova, size_t size)
{
	int ret;
	u32 tmp;

	writel_relaxed(F_INVLD_EN1 | F_INVLD_EN0,
		data->base + REG_MMU_INV_SEL);
	writel_relaxed(iova & F_MMU_FAULT_VA_MSK,
		data->base + REG_MMU_INVLD_START_A);
	writel_relaxed((iova + size - 1) & F_MMU_FAULT_VA_MSK,
		data->base + REG_MMU_INVLD_END_A);
	writel_relaxed(F_MMU_INV_RANGE, data->base + REG_MMU_INVALIDATE);

	ret = readl_poll_timeout_atomic(data->base + REG_MMU_CPE_DONE,
				tmp, tmp != 0, 10, 100000);
	if (ret) {
		dev_warn(data->dev,
			 "Partial TLB flush timed out, falling back to full flush\n");
		mtk_iommu_tlb_flush_all(data);
	}
	/* Clear the CPE status */
	writel_relaxed(0, data->base + REG_MMU_CPE_DONE);
}

static irqreturn_t mtk_iommu_isr(int irq, void *dev_id)
{
	struct mtk_iommu_data *data = dev_id;
	struct mtk_iommu_domain *dom = data->m4u_dom;
	u32 int_state, regval, fault_iova, fault_pa;
	unsigned int fault_larb, fault_port;

	/* Read error information from registers */
	int_state = readl_relaxed(data->base + REG_MMU_FAULT_ST);
	fault_iova = readl_relaxed(data->base + REG_MMU_FAULT_VA);

	fault_iova &= F_MMU_FAULT_VA_MSK;
	fault_pa = readl_relaxed(data->base + REG_MMU_INVLD_PA);
	regval = readl_relaxed(data->base + REG_MMU_INT_ID);
	fault_larb = MT2701_M4U_TF_LARB(regval);
	fault_port = MT2701_M4U_TF_PORT(regval);

	/*
	 * MTK v1 iommu HW could not determine whether the fault is read or
	 * write fault, report as read fault.
	 */
	if (report_iommu_fault(&dom->domain, data->dev, fault_iova,
			IOMMU_FAULT_READ))
		dev_err_ratelimited(data->dev,
			"fault type=0x%x iova=0x%x pa=0x%x larb=%d port=%d\n",
			int_state, fault_iova, fault_pa,
			fault_larb, fault_port);

	/* Interrupt clear */
	regval = readl_relaxed(data->base + REG_MMU_INT_CONTROL);
	regval |= F_INT_CLR_BIT;
	writel_relaxed(regval, data->base + REG_MMU_INT_CONTROL);

	mtk_iommu_tlb_flush_all(data);

	return IRQ_HANDLED;
}

static void mtk_iommu_config(struct mtk_iommu_data *data,
			     struct device *dev, bool enable)
{
	struct mtk_smi_larb_iommu    *larb_mmu;
	unsigned int                 larbid, portid;
	struct iommu_fwspec *fwspec = dev->iommu_fwspec;
	int i;

	for (i = 0; i < fwspec->num_ids; ++i) {
		larbid = mt2701_m4u_to_larb(fwspec->ids[i]);
		portid = mt2701_m4u_to_port(fwspec->ids[i]);
		larb_mmu = &data->smi_imu.larb_imu[larbid];

		dev_dbg(dev, "%s iommu port: %d\n",
			enable ? "enable" : "disable", portid);

		if (enable)
			larb_mmu->mmu |= MTK_SMI_MMU_EN(portid);
		else
			larb_mmu->mmu &= ~MTK_SMI_MMU_EN(portid);
	}
}

static int mtk_iommu_domain_finalise(struct mtk_iommu_data *data)
{
	struct mtk_iommu_domain *dom = data->m4u_dom;

	spin_lock_init(&dom->pgtlock);

	dom->pgt_va = dma_zalloc_coherent(data->dev,
				M2701_IOMMU_PGT_SIZE,
				&dom->pgt_pa, GFP_KERNEL);
	if (!dom->pgt_va)
		return -ENOMEM;

	writel(dom->pgt_pa, data->base + REG_MMU_PT_BASE_ADDR);

	dom->data = data;

	return 0;
}

static struct iommu_domain *mtk_iommu_domain_alloc(unsigned type)
{
	struct mtk_iommu_domain *dom;

	if (type != IOMMU_DOMAIN_UNMANAGED)
		return NULL;

	dom = kzalloc(sizeof(*dom), GFP_KERNEL);
	if (!dom)
		return NULL;

	return &dom->domain;
}

static void mtk_iommu_domain_free(struct iommu_domain *domain)
{
	struct mtk_iommu_domain *dom = to_mtk_domain(domain);
	struct mtk_iommu_data *data = dom->data;

	dma_free_coherent(data->dev, M2701_IOMMU_PGT_SIZE,
			dom->pgt_va, dom->pgt_pa);
	kfree(to_mtk_domain(domain));
}

static int mtk_iommu_attach_device(struct iommu_domain *domain,
				   struct device *dev)
{
	struct mtk_iommu_domain *dom = to_mtk_domain(domain);
	struct mtk_iommu_data *data = dev->iommu_fwspec->iommu_priv;
	int ret;

	if (!data)
		return -ENODEV;

	if (!data->m4u_dom) {
		data->m4u_dom = dom;
		ret = mtk_iommu_domain_finalise(data);
		if (ret) {
			data->m4u_dom = NULL;
			return ret;
		}
	}

	mtk_iommu_config(data, dev, true);
	return 0;
}

static void mtk_iommu_detach_device(struct iommu_domain *domain,
				    struct device *dev)
{
	struct mtk_iommu_data *data = dev->iommu_fwspec->iommu_priv;

	if (!data)
		return;

	mtk_iommu_config(data, dev, false);
}

static int mtk_iommu_map(struct iommu_domain *domain, unsigned long iova,
			 phys_addr_t paddr, size_t size, int prot)
{
	struct mtk_iommu_domain *dom = to_mtk_domain(domain);
	unsigned int page_num = size >> MT2701_IOMMU_PAGE_SHIFT;
	unsigned long flags;
	unsigned int i;
	u32 *pgt_base_iova = dom->pgt_va + (iova  >> MT2701_IOMMU_PAGE_SHIFT);
	u32 pabase = (u32)paddr;
	int map_size = 0;

	spin_lock_irqsave(&dom->pgtlock, flags);
	for (i = 0; i < page_num; i++) {
		if (pgt_base_iova[i]) {
			memset(pgt_base_iova, 0, i * sizeof(u32));
			break;
		}
		pgt_base_iova[i] = pabase | F_DESC_VALID | F_DESC_NONSEC;
		pabase += MT2701_IOMMU_PAGE_SIZE;
		map_size += MT2701_IOMMU_PAGE_SIZE;
	}

	spin_unlock_irqrestore(&dom->pgtlock, flags);

	mtk_iommu_tlb_flush_range(dom->data, iova, size);

	return map_size == size ? 0 : -EEXIST;
}

static size_t mtk_iommu_unmap(struct iommu_domain *domain,
			      unsigned long iova, size_t size)
{
	struct mtk_iommu_domain *dom = to_mtk_domain(domain);
	unsigned long flags;
	u32 *pgt_base_iova = dom->pgt_va + (iova  >> MT2701_IOMMU_PAGE_SHIFT);
	unsigned int page_num = size >> MT2701_IOMMU_PAGE_SHIFT;

	spin_lock_irqsave(&dom->pgtlock, flags);
	memset(pgt_base_iova, 0, page_num * sizeof(u32));
	spin_unlock_irqrestore(&dom->pgtlock, flags);

	mtk_iommu_tlb_flush_range(dom->data, iova, size);

	return size;
}

static phys_addr_t mtk_iommu_iova_to_phys(struct iommu_domain *domain,
					  dma_addr_t iova)
{
	struct mtk_iommu_domain *dom = to_mtk_domain(domain);
	unsigned long flags;
	phys_addr_t pa;

	spin_lock_irqsave(&dom->pgtlock, flags);
	pa = *(dom->pgt_va + (iova >> MT2701_IOMMU_PAGE_SHIFT));
	pa = pa & (~(MT2701_IOMMU_PAGE_SIZE - 1));
	spin_unlock_irqrestore(&dom->pgtlock, flags);

	return pa;
}

static struct iommu_ops mtk_iommu_ops;

/*
 * MTK generation one iommu HW only support one iommu domain, and all the client
 * sharing the same iova address space.
 */
static int mtk_iommu_create_mapping(struct device *dev,
				    struct of_phandle_args *args)
{
	struct mtk_iommu_data *data;
	struct platform_device *m4updev;
	struct dma_iommu_mapping *mtk_mapping;
	struct device *m4udev;
	int ret;

	if (args->args_count != 1) {
		dev_err(dev, "invalid #iommu-cells(%d) property for IOMMU\n",
			args->args_count);
		return -EINVAL;
	}

	if (!dev->iommu_fwspec) {
		ret = iommu_fwspec_init(dev, &args->np->fwnode, &mtk_iommu_ops);
		if (ret)
			return ret;
	} else if (dev->iommu_fwspec->ops != &mtk_iommu_ops) {
		return -EINVAL;
	}

	if (!dev->iommu_fwspec->iommu_priv) {
		/* Get the m4u device */
		m4updev = of_find_device_by_node(args->np);
		if (WARN_ON(!m4updev))
			return -EINVAL;

		dev->iommu_fwspec->iommu_priv = platform_get_drvdata(m4updev);
	}

	ret = iommu_fwspec_add_ids(dev, args->args, 1);
	if (ret)
		return ret;

	data = dev->iommu_fwspec->iommu_priv;
	m4udev = data->dev;
	mtk_mapping = m4udev->archdata.iommu;
	if (!mtk_mapping) {
		/* MTK iommu support 4GB iova address space. */
		mtk_mapping = arm_iommu_create_mapping(&platform_bus_type,
						0, 1ULL << 32);
		if (IS_ERR(mtk_mapping))
			return PTR_ERR(mtk_mapping);

		m4udev->archdata.iommu = mtk_mapping;
	}

	ret = arm_iommu_attach_device(dev, mtk_mapping);
	if (ret)
		goto err_release_mapping;

	return 0;

err_release_mapping:
	arm_iommu_release_mapping(mtk_mapping);
	m4udev->archdata.iommu = NULL;
	return ret;
}

static int mtk_iommu_add_device(struct device *dev)
{
	struct of_phandle_args iommu_spec;
	struct of_phandle_iterator it;
	struct mtk_iommu_data *data;
	struct iommu_group *group;
	int err;

	of_for_each_phandle(&it, err, dev->of_node, "iommus",
			"#iommu-cells", 0) {
		int count = of_phandle_iterator_args(&it, iommu_spec.args,
					MAX_PHANDLE_ARGS);
		iommu_spec.np = of_node_get(it.node);
		iommu_spec.args_count = count;

		mtk_iommu_create_mapping(dev, &iommu_spec);
		of_node_put(iommu_spec.np);
	}

	if (!dev->iommu_fwspec || dev->iommu_fwspec->ops != &mtk_iommu_ops)
		return -ENODEV; /* Not a iommu client device */

	data = dev->iommu_fwspec->iommu_priv;
	iommu_device_link(&data->iommu, dev);

	group = iommu_group_get_for_dev(dev);
	if (IS_ERR(group))
		return PTR_ERR(group);

	iommu_group_put(group);
	return 0;
}

static void mtk_iommu_remove_device(struct device *dev)
{
	struct mtk_iommu_data *data;

	if (!dev->iommu_fwspec || dev->iommu_fwspec->ops != &mtk_iommu_ops)
		return;

	data = dev->iommu_fwspec->iommu_priv;
	iommu_device_unlink(&data->iommu, dev);

	iommu_group_remove_device(dev);
	iommu_fwspec_free(dev);
}

static struct iommu_group *mtk_iommu_device_group(struct device *dev)
{
	struct mtk_iommu_data *data = dev->iommu_fwspec->iommu_priv;

	if (!data)
		return ERR_PTR(-ENODEV);

	/* All the client devices are in the same m4u iommu-group */
	if (!data->m4u_group) {
		data->m4u_group = iommu_group_alloc();
		if (IS_ERR(data->m4u_group))
			dev_err(dev, "Failed to allocate M4U IOMMU group\n");
	} else {
		iommu_group_ref_get(data->m4u_group);
	}
	return data->m4u_group;
}

static int mtk_iommu_hw_init(const struct mtk_iommu_data *data)
{
	u32 regval;
	int ret;

	ret = clk_prepare_enable(data->bclk);
	if (ret) {
		dev_err(data->dev, "Failed to enable iommu bclk(%d)\n", ret);
		return ret;
	}

	regval = F_MMU_CTRL_COHERENT_EN | F_MMU_TF_PROTECT_SEL(2);
	writel_relaxed(regval, data->base + REG_MMU_CTRL_REG);

	regval = F_INT_TRANSLATION_FAULT |
		F_INT_MAIN_MULTI_HIT_FAULT |
		F_INT_INVALID_PA_FAULT |
		F_INT_ENTRY_REPLACEMENT_FAULT |
		F_INT_TABLE_WALK_FAULT |
		F_INT_TLB_MISS_FAULT |
		F_INT_PFH_DMA_FIFO_OVERFLOW |
		F_INT_MISS_DMA_FIFO_OVERFLOW;
	writel_relaxed(regval, data->base + REG_MMU_INT_CONTROL);

	/* protect memory,hw will write here while translation fault */
	writel_relaxed(data->protect_base,
			data->base + REG_MMU_IVRP_PADDR);

	writel_relaxed(F_MMU_DCM_ON, data->base + REG_MMU_DCM);

	if (devm_request_irq(data->dev, data->irq, mtk_iommu_isr, 0,
			     dev_name(data->dev), (void *)data)) {
		writel_relaxed(0, data->base + REG_MMU_PT_BASE_ADDR);
		clk_disable_unprepare(data->bclk);
		dev_err(data->dev, "Failed @ IRQ-%d Request\n", data->irq);
		return -ENODEV;
	}

	return 0;
}

static struct iommu_ops mtk_iommu_ops = {
	.domain_alloc	= mtk_iommu_domain_alloc,
	.domain_free	= mtk_iommu_domain_free,
	.attach_dev	= mtk_iommu_attach_device,
	.detach_dev	= mtk_iommu_detach_device,
	.map		= mtk_iommu_map,
	.unmap		= mtk_iommu_unmap,
	.map_sg		= default_iommu_map_sg,
	.iova_to_phys	= mtk_iommu_iova_to_phys,
	.add_device	= mtk_iommu_add_device,
	.remove_device	= mtk_iommu_remove_device,
	.device_group	= mtk_iommu_device_group,
	.pgsize_bitmap	= ~0UL << MT2701_IOMMU_PAGE_SHIFT,
};

static const struct of_device_id mtk_iommu_of_ids[] = {
	{ .compatible = "mediatek,mt2701-m4u", },
	{}
};

static const struct component_master_ops mtk_iommu_com_ops = {
	.bind		= mtk_iommu_bind,
	.unbind		= mtk_iommu_unbind,
};

static int mtk_iommu_probe(struct platform_device *pdev)
{
	struct mtk_iommu_data		*data;
	struct device			*dev = &pdev->dev;
	struct resource			*res;
	struct component_match		*match = NULL;
	struct of_phandle_args		larb_spec;
	struct of_phandle_iterator	it;
	void				*protect;
	int				larb_nr, ret, err;

	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	data->dev = dev;

	/* Protect memory. HW will access here while translation fault.*/
	protect = devm_kzalloc(dev, MTK_PROTECT_PA_ALIGN * 2,
			GFP_KERNEL | GFP_DMA);
	if (!protect)
		return -ENOMEM;
	data->protect_base = ALIGN(virt_to_phys(protect), MTK_PROTECT_PA_ALIGN);

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	data->base = devm_ioremap_resource(dev, res);
	if (IS_ERR(data->base))
		return PTR_ERR(data->base);

	data->irq = platform_get_irq(pdev, 0);
	if (data->irq < 0)
		return data->irq;

	data->bclk = devm_clk_get(dev, "bclk");
	if (IS_ERR(data->bclk))
		return PTR_ERR(data->bclk);

	larb_nr = 0;
	of_for_each_phandle(&it, err, dev->of_node,
			"mediatek,larbs", NULL, 0) {
		struct platform_device *plarbdev;
		int count = of_phandle_iterator_args(&it, larb_spec.args,
					MAX_PHANDLE_ARGS);

		if (count)
			continue;

		larb_spec.np = of_node_get(it.node);
		if (!of_device_is_available(larb_spec.np))
			continue;

		plarbdev = of_find_device_by_node(larb_spec.np);
		if (!plarbdev) {
			plarbdev = of_platform_device_create(
						larb_spec.np, NULL,
						platform_bus_type.dev_root);
			if (!plarbdev) {
				of_node_put(larb_spec.np);
				return -EPROBE_DEFER;
			}
		}

		data->smi_imu.larb_imu[larb_nr].dev = &plarbdev->dev;
		component_match_add_release(dev, &match, release_of,
					    compare_of, larb_spec.np);
		larb_nr++;
	}

	data->smi_imu.larb_nr = larb_nr;

	platform_set_drvdata(pdev, data);

	ret = mtk_iommu_hw_init(data);
	if (ret)
		return ret;

	ret = iommu_device_sysfs_add(&data->iommu, &pdev->dev, NULL,
				     dev_name(&pdev->dev));
	if (ret)
		return ret;

	iommu_device_set_ops(&data->iommu, &mtk_iommu_ops);

	ret = iommu_device_register(&data->iommu);
	if (ret)
		return ret;

	if (!iommu_present(&platform_bus_type))
		bus_set_iommu(&platform_bus_type,  &mtk_iommu_ops);

	return component_master_add_with_match(dev, &mtk_iommu_com_ops, match);
}

static int mtk_iommu_remove(struct platform_device *pdev)
{
	struct mtk_iommu_data *data = platform_get_drvdata(pdev);

	iommu_device_sysfs_remove(&data->iommu);
	iommu_device_unregister(&data->iommu);

	if (iommu_present(&platform_bus_type))
		bus_set_iommu(&platform_bus_type, NULL);

	clk_disable_unprepare(data->bclk);
	devm_free_irq(&pdev->dev, data->irq, data);
	component_master_del(&pdev->dev, &mtk_iommu_com_ops);
	return 0;
}

static int __maybe_unused mtk_iommu_suspend(struct device *dev)
{
	struct mtk_iommu_data *data = dev_get_drvdata(dev);
	struct mtk_iommu_suspend_reg *reg = &data->reg;
	void __iomem *base = data->base;

	reg->standard_axi_mode = readl_relaxed(base +
					       REG_MMU_STANDARD_AXI_MODE);
	reg->dcm_dis = readl_relaxed(base + REG_MMU_DCM);
	reg->ctrl_reg = readl_relaxed(base + REG_MMU_CTRL_REG);
	reg->int_control0 = readl_relaxed(base + REG_MMU_INT_CONTROL);
	return 0;
}

static int __maybe_unused mtk_iommu_resume(struct device *dev)
{
	struct mtk_iommu_data *data = dev_get_drvdata(dev);
	struct mtk_iommu_suspend_reg *reg = &data->reg;
	void __iomem *base = data->base;

	writel_relaxed(data->m4u_dom->pgt_pa, base + REG_MMU_PT_BASE_ADDR);
	writel_relaxed(reg->standard_axi_mode,
		       base + REG_MMU_STANDARD_AXI_MODE);
	writel_relaxed(reg->dcm_dis, base + REG_MMU_DCM);
	writel_relaxed(reg->ctrl_reg, base + REG_MMU_CTRL_REG);
	writel_relaxed(reg->int_control0, base + REG_MMU_INT_CONTROL);
	writel_relaxed(data->protect_base, base + REG_MMU_IVRP_PADDR);
	return 0;
}

static const struct dev_pm_ops mtk_iommu_pm_ops = {
	SET_SYSTEM_SLEEP_PM_OPS(mtk_iommu_suspend, mtk_iommu_resume)
};

static struct platform_driver mtk_iommu_driver = {
	.probe	= mtk_iommu_probe,
	.remove	= mtk_iommu_remove,
	.driver	= {
		.name = "mtk-iommu",
		.of_match_table = mtk_iommu_of_ids,
		.pm = &mtk_iommu_pm_ops,
	}
};

static int __init m4u_init(void)
{
	return platform_driver_register(&mtk_iommu_driver);
}

static void __exit m4u_exit(void)
{
	return platform_driver_unregister(&mtk_iommu_driver);
}

subsys_initcall(m4u_init);
module_exit(m4u_exit);

MODULE_DESCRIPTION("IOMMU API for MTK architected m4u v1 implementations");
MODULE_AUTHOR("Honghui Zhang <honghui.zhang@mediatek.com>");
MODULE_LICENSE("GPL v2");