xref: /openbmc/linux/drivers/iommu/mtk_iommu.c (revision b9b77222)
1 /*
2  * Copyright (c) 2015-2016 MediaTek Inc.
3  * Author: Yong Wu <yong.wu@mediatek.com>
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  */
14 #include <linux/bootmem.h>
15 #include <linux/bug.h>
16 #include <linux/clk.h>
17 #include <linux/component.h>
18 #include <linux/device.h>
19 #include <linux/dma-iommu.h>
20 #include <linux/err.h>
21 #include <linux/interrupt.h>
22 #include <linux/io.h>
23 #include <linux/iommu.h>
24 #include <linux/iopoll.h>
25 #include <linux/list.h>
26 #include <linux/of_address.h>
27 #include <linux/of_iommu.h>
28 #include <linux/of_irq.h>
29 #include <linux/of_platform.h>
30 #include <linux/platform_device.h>
31 #include <linux/slab.h>
32 #include <linux/spinlock.h>
33 #include <asm/barrier.h>
34 #include <soc/mediatek/smi.h>
35 
36 #include "mtk_iommu.h"
37 
38 #define REG_MMU_PT_BASE_ADDR			0x000
39 
40 #define REG_MMU_INVALIDATE			0x020
41 #define F_ALL_INVLD				0x2
42 #define F_MMU_INV_RANGE				0x1
43 
44 #define REG_MMU_INVLD_START_A			0x024
45 #define REG_MMU_INVLD_END_A			0x028
46 
47 #define REG_MMU_INV_SEL				0x038
48 #define F_INVLD_EN0				BIT(0)
49 #define F_INVLD_EN1				BIT(1)
50 
51 #define REG_MMU_STANDARD_AXI_MODE		0x048
52 #define REG_MMU_DCM_DIS				0x050
53 
54 #define REG_MMU_CTRL_REG			0x110
55 #define F_MMU_PREFETCH_RT_REPLACE_MOD		BIT(4)
56 #define F_MMU_TF_PROTECT_SEL_SHIFT(data) \
57 	((data)->m4u_plat == M4U_MT2712 ? 4 : 5)
58 /* It's named by F_MMU_TF_PROT_SEL in mt2712. */
59 #define F_MMU_TF_PROTECT_SEL(prot, data) \
60 	(((prot) & 0x3) << F_MMU_TF_PROTECT_SEL_SHIFT(data))
61 
62 #define REG_MMU_IVRP_PADDR			0x114
63 
64 #define REG_MMU_VLD_PA_RNG			0x118
65 #define F_MMU_VLD_PA_RNG(EA, SA)		(((EA) << 8) | (SA))
66 
67 #define REG_MMU_INT_CONTROL0			0x120
68 #define F_L2_MULIT_HIT_EN			BIT(0)
69 #define F_TABLE_WALK_FAULT_INT_EN		BIT(1)
70 #define F_PREETCH_FIFO_OVERFLOW_INT_EN		BIT(2)
71 #define F_MISS_FIFO_OVERFLOW_INT_EN		BIT(3)
72 #define F_PREFETCH_FIFO_ERR_INT_EN		BIT(5)
73 #define F_MISS_FIFO_ERR_INT_EN			BIT(6)
74 #define F_INT_CLR_BIT				BIT(12)
75 
76 #define REG_MMU_INT_MAIN_CONTROL		0x124
77 #define F_INT_TRANSLATION_FAULT			BIT(0)
78 #define F_INT_MAIN_MULTI_HIT_FAULT		BIT(1)
79 #define F_INT_INVALID_PA_FAULT			BIT(2)
80 #define F_INT_ENTRY_REPLACEMENT_FAULT		BIT(3)
81 #define F_INT_TLB_MISS_FAULT			BIT(4)
82 #define F_INT_MISS_TRANSACTION_FIFO_FAULT	BIT(5)
83 #define F_INT_PRETETCH_TRANSATION_FIFO_FAULT	BIT(6)
84 
85 #define REG_MMU_CPE_DONE			0x12C
86 
87 #define REG_MMU_FAULT_ST1			0x134
88 
89 #define REG_MMU_FAULT_VA			0x13c
90 #define F_MMU_FAULT_VA_WRITE_BIT		BIT(1)
91 #define F_MMU_FAULT_VA_LAYER_BIT		BIT(0)
92 
93 #define REG_MMU_INVLD_PA			0x140
94 #define REG_MMU_INT_ID				0x150
95 #define F_MMU0_INT_ID_LARB_ID(a)		(((a) >> 7) & 0x7)
96 #define F_MMU0_INT_ID_PORT_ID(a)		(((a) >> 2) & 0x1f)
97 
98 #define MTK_PROTECT_PA_ALIGN			128
99 
100 /*
101  * Get the local arbiter ID and the portid within the larb arbiter
102  * from mtk_m4u_id which is defined by MTK_M4U_ID.
103  */
104 #define MTK_M4U_TO_LARB(id)		(((id) >> 5) & 0xf)
105 #define MTK_M4U_TO_PORT(id)		((id) & 0x1f)
106 
107 struct mtk_iommu_domain {
108 	spinlock_t			pgtlock; /* lock for page table */
109 
110 	struct io_pgtable_cfg		cfg;
111 	struct io_pgtable_ops		*iop;
112 
113 	struct iommu_domain		domain;
114 };
115 
116 static struct iommu_ops mtk_iommu_ops;
117 
118 static LIST_HEAD(m4ulist);	/* List all the M4U HWs */
119 
120 #define for_each_m4u(data)	list_for_each_entry(data, &m4ulist, list)
121 
122 /*
123  * There may be 1 or 2 M4U HWs, But we always expect they are in the same domain
124  * for the performance.
125  *
126  * Here always return the mtk_iommu_data of the first probed M4U where the
127  * iommu domain information is recorded.
128  */
129 static struct mtk_iommu_data *mtk_iommu_get_m4u_data(void)
130 {
131 	struct mtk_iommu_data *data;
132 
133 	for_each_m4u(data)
134 		return data;
135 
136 	return NULL;
137 }
138 
139 static struct mtk_iommu_domain *to_mtk_domain(struct iommu_domain *dom)
140 {
141 	return container_of(dom, struct mtk_iommu_domain, domain);
142 }
143 
144 static void mtk_iommu_tlb_flush_all(void *cookie)
145 {
146 	struct mtk_iommu_data *data = cookie;
147 
148 	for_each_m4u(data) {
149 		writel_relaxed(F_INVLD_EN1 | F_INVLD_EN0,
150 			       data->base + REG_MMU_INV_SEL);
151 		writel_relaxed(F_ALL_INVLD, data->base + REG_MMU_INVALIDATE);
152 		wmb(); /* Make sure the tlb flush all done */
153 	}
154 }
155 
156 static void mtk_iommu_tlb_add_flush_nosync(unsigned long iova, size_t size,
157 					   size_t granule, bool leaf,
158 					   void *cookie)
159 {
160 	struct mtk_iommu_data *data = cookie;
161 
162 	for_each_m4u(data) {
163 		writel_relaxed(F_INVLD_EN1 | F_INVLD_EN0,
164 			       data->base + REG_MMU_INV_SEL);
165 
166 		writel_relaxed(iova, data->base + REG_MMU_INVLD_START_A);
167 		writel_relaxed(iova + size - 1,
168 			       data->base + REG_MMU_INVLD_END_A);
169 		writel_relaxed(F_MMU_INV_RANGE,
170 			       data->base + REG_MMU_INVALIDATE);
171 		data->tlb_flush_active = true;
172 	}
173 }
174 
175 static void mtk_iommu_tlb_sync(void *cookie)
176 {
177 	struct mtk_iommu_data *data = cookie;
178 	int ret;
179 	u32 tmp;
180 
181 	for_each_m4u(data) {
182 		/* Avoid timing out if there's nothing to wait for */
183 		if (!data->tlb_flush_active)
184 			return;
185 
186 		ret = readl_poll_timeout_atomic(data->base + REG_MMU_CPE_DONE,
187 						tmp, tmp != 0, 10, 100000);
188 		if (ret) {
189 			dev_warn(data->dev,
190 				 "Partial TLB flush timed out, falling back to full flush\n");
191 			mtk_iommu_tlb_flush_all(cookie);
192 		}
193 		/* Clear the CPE status */
194 		writel_relaxed(0, data->base + REG_MMU_CPE_DONE);
195 		data->tlb_flush_active = false;
196 	}
197 }
198 
199 static const struct iommu_gather_ops mtk_iommu_gather_ops = {
200 	.tlb_flush_all = mtk_iommu_tlb_flush_all,
201 	.tlb_add_flush = mtk_iommu_tlb_add_flush_nosync,
202 	.tlb_sync = mtk_iommu_tlb_sync,
203 };
204 
205 static irqreturn_t mtk_iommu_isr(int irq, void *dev_id)
206 {
207 	struct mtk_iommu_data *data = dev_id;
208 	struct mtk_iommu_domain *dom = data->m4u_dom;
209 	u32 int_state, regval, fault_iova, fault_pa;
210 	unsigned int fault_larb, fault_port;
211 	bool layer, write;
212 
213 	/* Read error info from registers */
214 	int_state = readl_relaxed(data->base + REG_MMU_FAULT_ST1);
215 	fault_iova = readl_relaxed(data->base + REG_MMU_FAULT_VA);
216 	layer = fault_iova & F_MMU_FAULT_VA_LAYER_BIT;
217 	write = fault_iova & F_MMU_FAULT_VA_WRITE_BIT;
218 	fault_pa = readl_relaxed(data->base + REG_MMU_INVLD_PA);
219 	regval = readl_relaxed(data->base + REG_MMU_INT_ID);
220 	fault_larb = F_MMU0_INT_ID_LARB_ID(regval);
221 	fault_port = F_MMU0_INT_ID_PORT_ID(regval);
222 
223 	if (report_iommu_fault(&dom->domain, data->dev, fault_iova,
224 			       write ? IOMMU_FAULT_WRITE : IOMMU_FAULT_READ)) {
225 		dev_err_ratelimited(
226 			data->dev,
227 			"fault type=0x%x iova=0x%x pa=0x%x larb=%d port=%d layer=%d %s\n",
228 			int_state, fault_iova, fault_pa, fault_larb, fault_port,
229 			layer, write ? "write" : "read");
230 	}
231 
232 	/* Interrupt clear */
233 	regval = readl_relaxed(data->base + REG_MMU_INT_CONTROL0);
234 	regval |= F_INT_CLR_BIT;
235 	writel_relaxed(regval, data->base + REG_MMU_INT_CONTROL0);
236 
237 	mtk_iommu_tlb_flush_all(data);
238 
239 	return IRQ_HANDLED;
240 }
241 
242 static void mtk_iommu_config(struct mtk_iommu_data *data,
243 			     struct device *dev, bool enable)
244 {
245 	struct mtk_smi_larb_iommu    *larb_mmu;
246 	unsigned int                 larbid, portid;
247 	struct iommu_fwspec *fwspec = dev->iommu_fwspec;
248 	int i;
249 
250 	for (i = 0; i < fwspec->num_ids; ++i) {
251 		larbid = MTK_M4U_TO_LARB(fwspec->ids[i]);
252 		portid = MTK_M4U_TO_PORT(fwspec->ids[i]);
253 		larb_mmu = &data->smi_imu.larb_imu[larbid];
254 
255 		dev_dbg(dev, "%s iommu port: %d\n",
256 			enable ? "enable" : "disable", portid);
257 
258 		if (enable)
259 			larb_mmu->mmu |= MTK_SMI_MMU_EN(portid);
260 		else
261 			larb_mmu->mmu &= ~MTK_SMI_MMU_EN(portid);
262 	}
263 }
264 
265 static int mtk_iommu_domain_finalise(struct mtk_iommu_domain *dom)
266 {
267 	struct mtk_iommu_data *data = mtk_iommu_get_m4u_data();
268 
269 	spin_lock_init(&dom->pgtlock);
270 
271 	dom->cfg = (struct io_pgtable_cfg) {
272 		.quirks = IO_PGTABLE_QUIRK_ARM_NS |
273 			IO_PGTABLE_QUIRK_NO_PERMS |
274 			IO_PGTABLE_QUIRK_TLBI_ON_MAP,
275 		.pgsize_bitmap = mtk_iommu_ops.pgsize_bitmap,
276 		.ias = 32,
277 		.oas = 32,
278 		.tlb = &mtk_iommu_gather_ops,
279 		.iommu_dev = data->dev,
280 	};
281 
282 	if (data->enable_4GB)
283 		dom->cfg.quirks |= IO_PGTABLE_QUIRK_ARM_MTK_4GB;
284 
285 	dom->iop = alloc_io_pgtable_ops(ARM_V7S, &dom->cfg, data);
286 	if (!dom->iop) {
287 		dev_err(data->dev, "Failed to alloc io pgtable\n");
288 		return -EINVAL;
289 	}
290 
291 	/* Update our support page sizes bitmap */
292 	dom->domain.pgsize_bitmap = dom->cfg.pgsize_bitmap;
293 	return 0;
294 }
295 
296 static struct iommu_domain *mtk_iommu_domain_alloc(unsigned type)
297 {
298 	struct mtk_iommu_domain *dom;
299 
300 	if (type != IOMMU_DOMAIN_DMA)
301 		return NULL;
302 
303 	dom = kzalloc(sizeof(*dom), GFP_KERNEL);
304 	if (!dom)
305 		return NULL;
306 
307 	if (iommu_get_dma_cookie(&dom->domain))
308 		goto  free_dom;
309 
310 	if (mtk_iommu_domain_finalise(dom))
311 		goto  put_dma_cookie;
312 
313 	dom->domain.geometry.aperture_start = 0;
314 	dom->domain.geometry.aperture_end = DMA_BIT_MASK(32);
315 	dom->domain.geometry.force_aperture = true;
316 
317 	return &dom->domain;
318 
319 put_dma_cookie:
320 	iommu_put_dma_cookie(&dom->domain);
321 free_dom:
322 	kfree(dom);
323 	return NULL;
324 }
325 
326 static void mtk_iommu_domain_free(struct iommu_domain *domain)
327 {
328 	struct mtk_iommu_domain *dom = to_mtk_domain(domain);
329 
330 	free_io_pgtable_ops(dom->iop);
331 	iommu_put_dma_cookie(domain);
332 	kfree(to_mtk_domain(domain));
333 }
334 
335 static int mtk_iommu_attach_device(struct iommu_domain *domain,
336 				   struct device *dev)
337 {
338 	struct mtk_iommu_domain *dom = to_mtk_domain(domain);
339 	struct mtk_iommu_data *data = dev->iommu_fwspec->iommu_priv;
340 
341 	if (!data)
342 		return -ENODEV;
343 
344 	/* Update the pgtable base address register of the M4U HW */
345 	if (!data->m4u_dom) {
346 		data->m4u_dom = dom;
347 		writel(dom->cfg.arm_v7s_cfg.ttbr[0],
348 		       data->base + REG_MMU_PT_BASE_ADDR);
349 	}
350 
351 	mtk_iommu_config(data, dev, true);
352 	return 0;
353 }
354 
355 static void mtk_iommu_detach_device(struct iommu_domain *domain,
356 				    struct device *dev)
357 {
358 	struct mtk_iommu_data *data = dev->iommu_fwspec->iommu_priv;
359 
360 	if (!data)
361 		return;
362 
363 	mtk_iommu_config(data, dev, false);
364 }
365 
366 static int mtk_iommu_map(struct iommu_domain *domain, unsigned long iova,
367 			 phys_addr_t paddr, size_t size, int prot)
368 {
369 	struct mtk_iommu_domain *dom = to_mtk_domain(domain);
370 	unsigned long flags;
371 	int ret;
372 
373 	spin_lock_irqsave(&dom->pgtlock, flags);
374 	ret = dom->iop->map(dom->iop, iova, paddr & DMA_BIT_MASK(32),
375 			    size, prot);
376 	spin_unlock_irqrestore(&dom->pgtlock, flags);
377 
378 	return ret;
379 }
380 
381 static size_t mtk_iommu_unmap(struct iommu_domain *domain,
382 			      unsigned long iova, size_t size)
383 {
384 	struct mtk_iommu_domain *dom = to_mtk_domain(domain);
385 	unsigned long flags;
386 	size_t unmapsz;
387 
388 	spin_lock_irqsave(&dom->pgtlock, flags);
389 	unmapsz = dom->iop->unmap(dom->iop, iova, size);
390 	spin_unlock_irqrestore(&dom->pgtlock, flags);
391 
392 	return unmapsz;
393 }
394 
395 static void mtk_iommu_iotlb_sync(struct iommu_domain *domain)
396 {
397 	mtk_iommu_tlb_sync(mtk_iommu_get_m4u_data());
398 }
399 
400 static phys_addr_t mtk_iommu_iova_to_phys(struct iommu_domain *domain,
401 					  dma_addr_t iova)
402 {
403 	struct mtk_iommu_domain *dom = to_mtk_domain(domain);
404 	struct mtk_iommu_data *data = mtk_iommu_get_m4u_data();
405 	unsigned long flags;
406 	phys_addr_t pa;
407 
408 	spin_lock_irqsave(&dom->pgtlock, flags);
409 	pa = dom->iop->iova_to_phys(dom->iop, iova);
410 	spin_unlock_irqrestore(&dom->pgtlock, flags);
411 
412 	if (data->enable_4GB)
413 		pa |= BIT_ULL(32);
414 
415 	return pa;
416 }
417 
418 static int mtk_iommu_add_device(struct device *dev)
419 {
420 	struct mtk_iommu_data *data;
421 	struct iommu_group *group;
422 
423 	if (!dev->iommu_fwspec || dev->iommu_fwspec->ops != &mtk_iommu_ops)
424 		return -ENODEV; /* Not a iommu client device */
425 
426 	data = dev->iommu_fwspec->iommu_priv;
427 	iommu_device_link(&data->iommu, dev);
428 
429 	group = iommu_group_get_for_dev(dev);
430 	if (IS_ERR(group))
431 		return PTR_ERR(group);
432 
433 	iommu_group_put(group);
434 	return 0;
435 }
436 
437 static void mtk_iommu_remove_device(struct device *dev)
438 {
439 	struct mtk_iommu_data *data;
440 
441 	if (!dev->iommu_fwspec || dev->iommu_fwspec->ops != &mtk_iommu_ops)
442 		return;
443 
444 	data = dev->iommu_fwspec->iommu_priv;
445 	iommu_device_unlink(&data->iommu, dev);
446 
447 	iommu_group_remove_device(dev);
448 	iommu_fwspec_free(dev);
449 }
450 
451 static struct iommu_group *mtk_iommu_device_group(struct device *dev)
452 {
453 	struct mtk_iommu_data *data = mtk_iommu_get_m4u_data();
454 
455 	if (!data)
456 		return ERR_PTR(-ENODEV);
457 
458 	/* All the client devices are in the same m4u iommu-group */
459 	if (!data->m4u_group) {
460 		data->m4u_group = iommu_group_alloc();
461 		if (IS_ERR(data->m4u_group))
462 			dev_err(dev, "Failed to allocate M4U IOMMU group\n");
463 	} else {
464 		iommu_group_ref_get(data->m4u_group);
465 	}
466 	return data->m4u_group;
467 }
468 
469 static int mtk_iommu_of_xlate(struct device *dev, struct of_phandle_args *args)
470 {
471 	struct platform_device *m4updev;
472 
473 	if (args->args_count != 1) {
474 		dev_err(dev, "invalid #iommu-cells(%d) property for IOMMU\n",
475 			args->args_count);
476 		return -EINVAL;
477 	}
478 
479 	if (!dev->iommu_fwspec->iommu_priv) {
480 		/* Get the m4u device */
481 		m4updev = of_find_device_by_node(args->np);
482 		if (WARN_ON(!m4updev))
483 			return -EINVAL;
484 
485 		dev->iommu_fwspec->iommu_priv = platform_get_drvdata(m4updev);
486 	}
487 
488 	return iommu_fwspec_add_ids(dev, args->args, 1);
489 }
490 
491 static struct iommu_ops mtk_iommu_ops = {
492 	.domain_alloc	= mtk_iommu_domain_alloc,
493 	.domain_free	= mtk_iommu_domain_free,
494 	.attach_dev	= mtk_iommu_attach_device,
495 	.detach_dev	= mtk_iommu_detach_device,
496 	.map		= mtk_iommu_map,
497 	.unmap		= mtk_iommu_unmap,
498 	.map_sg		= default_iommu_map_sg,
499 	.flush_iotlb_all = mtk_iommu_iotlb_sync,
500 	.iotlb_sync	= mtk_iommu_iotlb_sync,
501 	.iova_to_phys	= mtk_iommu_iova_to_phys,
502 	.add_device	= mtk_iommu_add_device,
503 	.remove_device	= mtk_iommu_remove_device,
504 	.device_group	= mtk_iommu_device_group,
505 	.of_xlate	= mtk_iommu_of_xlate,
506 	.pgsize_bitmap	= SZ_4K | SZ_64K | SZ_1M | SZ_16M,
507 };
508 
509 static int mtk_iommu_hw_init(const struct mtk_iommu_data *data)
510 {
511 	u32 regval;
512 	int ret;
513 
514 	ret = clk_prepare_enable(data->bclk);
515 	if (ret) {
516 		dev_err(data->dev, "Failed to enable iommu bclk(%d)\n", ret);
517 		return ret;
518 	}
519 
520 	regval = F_MMU_TF_PROTECT_SEL(2, data);
521 	if (data->m4u_plat == M4U_MT8173)
522 		regval |= F_MMU_PREFETCH_RT_REPLACE_MOD;
523 	writel_relaxed(regval, data->base + REG_MMU_CTRL_REG);
524 
525 	regval = F_L2_MULIT_HIT_EN |
526 		F_TABLE_WALK_FAULT_INT_EN |
527 		F_PREETCH_FIFO_OVERFLOW_INT_EN |
528 		F_MISS_FIFO_OVERFLOW_INT_EN |
529 		F_PREFETCH_FIFO_ERR_INT_EN |
530 		F_MISS_FIFO_ERR_INT_EN;
531 	writel_relaxed(regval, data->base + REG_MMU_INT_CONTROL0);
532 
533 	regval = F_INT_TRANSLATION_FAULT |
534 		F_INT_MAIN_MULTI_HIT_FAULT |
535 		F_INT_INVALID_PA_FAULT |
536 		F_INT_ENTRY_REPLACEMENT_FAULT |
537 		F_INT_TLB_MISS_FAULT |
538 		F_INT_MISS_TRANSACTION_FIFO_FAULT |
539 		F_INT_PRETETCH_TRANSATION_FIFO_FAULT;
540 	writel_relaxed(regval, data->base + REG_MMU_INT_MAIN_CONTROL);
541 
542 	if (data->m4u_plat == M4U_MT8173)
543 		regval = (data->protect_base >> 1) | (data->enable_4GB << 31);
544 	else
545 		regval = lower_32_bits(data->protect_base) |
546 			 upper_32_bits(data->protect_base);
547 	writel_relaxed(regval, data->base + REG_MMU_IVRP_PADDR);
548 
549 	if (data->enable_4GB && data->m4u_plat != M4U_MT8173) {
550 		/*
551 		 * If 4GB mode is enabled, the validate PA range is from
552 		 * 0x1_0000_0000 to 0x1_ffff_ffff. here record bit[32:30].
553 		 */
554 		regval = F_MMU_VLD_PA_RNG(7, 4);
555 		writel_relaxed(regval, data->base + REG_MMU_VLD_PA_RNG);
556 	}
557 	writel_relaxed(0, data->base + REG_MMU_DCM_DIS);
558 
559 	/* It's MISC control register whose default value is ok except mt8173.*/
560 	if (data->m4u_plat == M4U_MT8173)
561 		writel_relaxed(0, data->base + REG_MMU_STANDARD_AXI_MODE);
562 
563 	if (devm_request_irq(data->dev, data->irq, mtk_iommu_isr, 0,
564 			     dev_name(data->dev), (void *)data)) {
565 		writel_relaxed(0, data->base + REG_MMU_PT_BASE_ADDR);
566 		clk_disable_unprepare(data->bclk);
567 		dev_err(data->dev, "Failed @ IRQ-%d Request\n", data->irq);
568 		return -ENODEV;
569 	}
570 
571 	return 0;
572 }
573 
574 static const struct component_master_ops mtk_iommu_com_ops = {
575 	.bind		= mtk_iommu_bind,
576 	.unbind		= mtk_iommu_unbind,
577 };
578 
579 static int mtk_iommu_probe(struct platform_device *pdev)
580 {
581 	struct mtk_iommu_data   *data;
582 	struct device           *dev = &pdev->dev;
583 	struct resource         *res;
584 	resource_size_t		ioaddr;
585 	struct component_match  *match = NULL;
586 	void                    *protect;
587 	int                     i, larb_nr, ret;
588 
589 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
590 	if (!data)
591 		return -ENOMEM;
592 	data->dev = dev;
593 	data->m4u_plat = (enum mtk_iommu_plat)of_device_get_match_data(dev);
594 
595 	/* Protect memory. HW will access here while translation fault.*/
596 	protect = devm_kzalloc(dev, MTK_PROTECT_PA_ALIGN * 2, GFP_KERNEL);
597 	if (!protect)
598 		return -ENOMEM;
599 	data->protect_base = ALIGN(virt_to_phys(protect), MTK_PROTECT_PA_ALIGN);
600 
601 	/* Whether the current dram is over 4GB */
602 	data->enable_4GB = !!(max_pfn > (BIT_ULL(32) >> PAGE_SHIFT));
603 
604 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
605 	data->base = devm_ioremap_resource(dev, res);
606 	if (IS_ERR(data->base))
607 		return PTR_ERR(data->base);
608 	ioaddr = res->start;
609 
610 	data->irq = platform_get_irq(pdev, 0);
611 	if (data->irq < 0)
612 		return data->irq;
613 
614 	data->bclk = devm_clk_get(dev, "bclk");
615 	if (IS_ERR(data->bclk))
616 		return PTR_ERR(data->bclk);
617 
618 	larb_nr = of_count_phandle_with_args(dev->of_node,
619 					     "mediatek,larbs", NULL);
620 	if (larb_nr < 0)
621 		return larb_nr;
622 	data->smi_imu.larb_nr = larb_nr;
623 
624 	for (i = 0; i < larb_nr; i++) {
625 		struct device_node *larbnode;
626 		struct platform_device *plarbdev;
627 		u32 id;
628 
629 		larbnode = of_parse_phandle(dev->of_node, "mediatek,larbs", i);
630 		if (!larbnode)
631 			return -EINVAL;
632 
633 		if (!of_device_is_available(larbnode))
634 			continue;
635 
636 		ret = of_property_read_u32(larbnode, "mediatek,larb-id", &id);
637 		if (ret)/* The id is consecutive if there is no this property */
638 			id = i;
639 
640 		plarbdev = of_find_device_by_node(larbnode);
641 		if (!plarbdev)
642 			return -EPROBE_DEFER;
643 		data->smi_imu.larb_imu[id].dev = &plarbdev->dev;
644 
645 		component_match_add_release(dev, &match, release_of,
646 					    compare_of, larbnode);
647 	}
648 
649 	platform_set_drvdata(pdev, data);
650 
651 	ret = mtk_iommu_hw_init(data);
652 	if (ret)
653 		return ret;
654 
655 	ret = iommu_device_sysfs_add(&data->iommu, dev, NULL,
656 				     "mtk-iommu.%pa", &ioaddr);
657 	if (ret)
658 		return ret;
659 
660 	iommu_device_set_ops(&data->iommu, &mtk_iommu_ops);
661 	iommu_device_set_fwnode(&data->iommu, &pdev->dev.of_node->fwnode);
662 
663 	ret = iommu_device_register(&data->iommu);
664 	if (ret)
665 		return ret;
666 
667 	list_add_tail(&data->list, &m4ulist);
668 
669 	if (!iommu_present(&platform_bus_type))
670 		bus_set_iommu(&platform_bus_type, &mtk_iommu_ops);
671 
672 	return component_master_add_with_match(dev, &mtk_iommu_com_ops, match);
673 }
674 
675 static int mtk_iommu_remove(struct platform_device *pdev)
676 {
677 	struct mtk_iommu_data *data = platform_get_drvdata(pdev);
678 
679 	iommu_device_sysfs_remove(&data->iommu);
680 	iommu_device_unregister(&data->iommu);
681 
682 	if (iommu_present(&platform_bus_type))
683 		bus_set_iommu(&platform_bus_type, NULL);
684 
685 	clk_disable_unprepare(data->bclk);
686 	devm_free_irq(&pdev->dev, data->irq, data);
687 	component_master_del(&pdev->dev, &mtk_iommu_com_ops);
688 	return 0;
689 }
690 
691 static int __maybe_unused mtk_iommu_suspend(struct device *dev)
692 {
693 	struct mtk_iommu_data *data = dev_get_drvdata(dev);
694 	struct mtk_iommu_suspend_reg *reg = &data->reg;
695 	void __iomem *base = data->base;
696 
697 	reg->standard_axi_mode = readl_relaxed(base +
698 					       REG_MMU_STANDARD_AXI_MODE);
699 	reg->dcm_dis = readl_relaxed(base + REG_MMU_DCM_DIS);
700 	reg->ctrl_reg = readl_relaxed(base + REG_MMU_CTRL_REG);
701 	reg->int_control0 = readl_relaxed(base + REG_MMU_INT_CONTROL0);
702 	reg->int_main_control = readl_relaxed(base + REG_MMU_INT_MAIN_CONTROL);
703 	reg->ivrp_paddr = readl_relaxed(base + REG_MMU_IVRP_PADDR);
704 	clk_disable_unprepare(data->bclk);
705 	return 0;
706 }
707 
708 static int __maybe_unused mtk_iommu_resume(struct device *dev)
709 {
710 	struct mtk_iommu_data *data = dev_get_drvdata(dev);
711 	struct mtk_iommu_suspend_reg *reg = &data->reg;
712 	void __iomem *base = data->base;
713 	int ret;
714 
715 	ret = clk_prepare_enable(data->bclk);
716 	if (ret) {
717 		dev_err(data->dev, "Failed to enable clk(%d) in resume\n", ret);
718 		return ret;
719 	}
720 	writel_relaxed(reg->standard_axi_mode,
721 		       base + REG_MMU_STANDARD_AXI_MODE);
722 	writel_relaxed(reg->dcm_dis, base + REG_MMU_DCM_DIS);
723 	writel_relaxed(reg->ctrl_reg, base + REG_MMU_CTRL_REG);
724 	writel_relaxed(reg->int_control0, base + REG_MMU_INT_CONTROL0);
725 	writel_relaxed(reg->int_main_control, base + REG_MMU_INT_MAIN_CONTROL);
726 	writel_relaxed(reg->ivrp_paddr, base + REG_MMU_IVRP_PADDR);
727 	if (data->m4u_dom)
728 		writel(data->m4u_dom->cfg.arm_v7s_cfg.ttbr[0],
729 		       base + REG_MMU_PT_BASE_ADDR);
730 	return 0;
731 }
732 
733 static const struct dev_pm_ops mtk_iommu_pm_ops = {
734 	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(mtk_iommu_suspend, mtk_iommu_resume)
735 };
736 
737 static const struct of_device_id mtk_iommu_of_ids[] = {
738 	{ .compatible = "mediatek,mt2712-m4u", .data = (void *)M4U_MT2712},
739 	{ .compatible = "mediatek,mt8173-m4u", .data = (void *)M4U_MT8173},
740 	{}
741 };
742 
743 static struct platform_driver mtk_iommu_driver = {
744 	.probe	= mtk_iommu_probe,
745 	.remove	= mtk_iommu_remove,
746 	.driver	= {
747 		.name = "mtk-iommu",
748 		.of_match_table = of_match_ptr(mtk_iommu_of_ids),
749 		.pm = &mtk_iommu_pm_ops,
750 	}
751 };
752 
753 static int __init mtk_iommu_init(void)
754 {
755 	int ret;
756 
757 	ret = platform_driver_register(&mtk_iommu_driver);
758 	if (ret != 0)
759 		pr_err("Failed to register MTK IOMMU driver\n");
760 
761 	return ret;
762 }
763 
764 subsys_initcall(mtk_iommu_init)
765