bc1efbfb9ddf0f121a213f9919f7e3ea0fa957ca
[platform/kernel/linux-exynos.git] / drivers / iommu / mtk_iommu_v1.c
1 /*
2  * Copyright (c) 2015-2016 MediaTek Inc.
3  * Author: Honghui Zhang <honghui.zhang@mediatek.com>
4  *
5  * Based on driver/iommu/mtk_iommu.c
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  */
16 #include <linux/bootmem.h>
17 #include <linux/bug.h>
18 #include <linux/clk.h>
19 #include <linux/component.h>
20 #include <linux/device.h>
21 #include <linux/dma-mapping.h>
22 #include <linux/dma-iommu.h>
23 #include <linux/err.h>
24 #include <linux/interrupt.h>
25 #include <linux/io.h>
26 #include <linux/iommu.h>
27 #include <linux/iopoll.h>
28 #include <linux/kmemleak.h>
29 #include <linux/list.h>
30 #include <linux/of_address.h>
31 #include <linux/of_iommu.h>
32 #include <linux/of_irq.h>
33 #include <linux/of_platform.h>
34 #include <linux/platform_device.h>
35 #include <linux/slab.h>
36 #include <linux/spinlock.h>
37 #include <asm/barrier.h>
38 #include <asm/dma-iommu.h>
39 #include <linux/module.h>
40 #include <dt-bindings/memory/mt2701-larb-port.h>
41 #include <soc/mediatek/smi.h>
42 #include "mtk_iommu.h"
43
44 #define REG_MMU_PT_BASE_ADDR                    0x000
45
46 #define F_ALL_INVLD                             0x2
47 #define F_MMU_INV_RANGE                         0x1
48 #define F_INVLD_EN0                             BIT(0)
49 #define F_INVLD_EN1                             BIT(1)
50
51 #define F_MMU_FAULT_VA_MSK                      0xfffff000
52 #define MTK_PROTECT_PA_ALIGN                    128
53
54 #define REG_MMU_CTRL_REG                        0x210
55 #define F_MMU_CTRL_COHERENT_EN                  BIT(8)
56 #define REG_MMU_IVRP_PADDR                      0x214
57 #define REG_MMU_INT_CONTROL                     0x220
58 #define F_INT_TRANSLATION_FAULT                 BIT(0)
59 #define F_INT_MAIN_MULTI_HIT_FAULT              BIT(1)
60 #define F_INT_INVALID_PA_FAULT                  BIT(2)
61 #define F_INT_ENTRY_REPLACEMENT_FAULT           BIT(3)
62 #define F_INT_TABLE_WALK_FAULT                  BIT(4)
63 #define F_INT_TLB_MISS_FAULT                    BIT(5)
64 #define F_INT_PFH_DMA_FIFO_OVERFLOW             BIT(6)
65 #define F_INT_MISS_DMA_FIFO_OVERFLOW            BIT(7)
66
67 #define F_MMU_TF_PROTECT_SEL(prot)              (((prot) & 0x3) << 5)
68 #define F_INT_CLR_BIT                           BIT(12)
69
70 #define REG_MMU_FAULT_ST                        0x224
71 #define REG_MMU_FAULT_VA                        0x228
72 #define REG_MMU_INVLD_PA                        0x22C
73 #define REG_MMU_INT_ID                          0x388
74 #define REG_MMU_INVALIDATE                      0x5c0
75 #define REG_MMU_INVLD_START_A                   0x5c4
76 #define REG_MMU_INVLD_END_A                     0x5c8
77
78 #define REG_MMU_INV_SEL                         0x5d8
79 #define REG_MMU_STANDARD_AXI_MODE               0x5e8
80
81 #define REG_MMU_DCM                             0x5f0
82 #define F_MMU_DCM_ON                            BIT(1)
83 #define REG_MMU_CPE_DONE                        0x60c
84 #define F_DESC_VALID                            0x2
85 #define F_DESC_NONSEC                           BIT(3)
86 #define MT2701_M4U_TF_LARB(TF)                  (6 - (((TF) >> 13) & 0x7))
87 #define MT2701_M4U_TF_PORT(TF)                  (((TF) >> 8) & 0xF)
88 /* MTK generation one iommu HW only support 4K size mapping */
89 #define MT2701_IOMMU_PAGE_SHIFT                 12
90 #define MT2701_IOMMU_PAGE_SIZE                  (1UL << MT2701_IOMMU_PAGE_SHIFT)
91
92 /*
93  * MTK m4u support 4GB iova address space, and only support 4K page
94  * mapping. So the pagetable size should be exactly as 4M.
95  */
96 #define M2701_IOMMU_PGT_SIZE                    SZ_4M
97
98 struct mtk_iommu_domain {
99         spinlock_t                      pgtlock; /* lock for page table */
100         struct iommu_domain             domain;
101         u32                             *pgt_va;
102         dma_addr_t                      pgt_pa;
103         struct mtk_iommu_data           *data;
104 };
105
106 static struct mtk_iommu_domain *to_mtk_domain(struct iommu_domain *dom)
107 {
108         return container_of(dom, struct mtk_iommu_domain, domain);
109 }
110
111 static const int mt2701_m4u_in_larb[] = {
112         LARB0_PORT_OFFSET, LARB1_PORT_OFFSET,
113         LARB2_PORT_OFFSET, LARB3_PORT_OFFSET
114 };
115
116 static inline int mt2701_m4u_to_larb(int id)
117 {
118         int i;
119
120         for (i = ARRAY_SIZE(mt2701_m4u_in_larb) - 1; i >= 0; i--)
121                 if ((id) >= mt2701_m4u_in_larb[i])
122                         return i;
123
124         return 0;
125 }
126
127 static inline int mt2701_m4u_to_port(int id)
128 {
129         int larb = mt2701_m4u_to_larb(id);
130
131         return id - mt2701_m4u_in_larb[larb];
132 }
133
134 static void mtk_iommu_tlb_flush_all(struct mtk_iommu_data *data)
135 {
136         writel_relaxed(F_INVLD_EN1 | F_INVLD_EN0,
137                         data->base + REG_MMU_INV_SEL);
138         writel_relaxed(F_ALL_INVLD, data->base + REG_MMU_INVALIDATE);
139         wmb(); /* Make sure the tlb flush all done */
140 }
141
142 static void mtk_iommu_tlb_flush_range(struct mtk_iommu_data *data,
143                                 unsigned long iova, size_t size)
144 {
145         int ret;
146         u32 tmp;
147
148         writel_relaxed(F_INVLD_EN1 | F_INVLD_EN0,
149                 data->base + REG_MMU_INV_SEL);
150         writel_relaxed(iova & F_MMU_FAULT_VA_MSK,
151                 data->base + REG_MMU_INVLD_START_A);
152         writel_relaxed((iova + size - 1) & F_MMU_FAULT_VA_MSK,
153                 data->base + REG_MMU_INVLD_END_A);
154         writel_relaxed(F_MMU_INV_RANGE, data->base + REG_MMU_INVALIDATE);
155
156         ret = readl_poll_timeout_atomic(data->base + REG_MMU_CPE_DONE,
157                                 tmp, tmp != 0, 10, 100000);
158         if (ret) {
159                 dev_warn(data->dev,
160                          "Partial TLB flush timed out, falling back to full flush\n");
161                 mtk_iommu_tlb_flush_all(data);
162         }
163         /* Clear the CPE status */
164         writel_relaxed(0, data->base + REG_MMU_CPE_DONE);
165 }
166
167 static irqreturn_t mtk_iommu_isr(int irq, void *dev_id)
168 {
169         struct mtk_iommu_data *data = dev_id;
170         struct mtk_iommu_domain *dom = data->m4u_dom;
171         u32 int_state, regval, fault_iova, fault_pa;
172         unsigned int fault_larb, fault_port;
173
174         /* Read error information from registers */
175         int_state = readl_relaxed(data->base + REG_MMU_FAULT_ST);
176         fault_iova = readl_relaxed(data->base + REG_MMU_FAULT_VA);
177
178         fault_iova &= F_MMU_FAULT_VA_MSK;
179         fault_pa = readl_relaxed(data->base + REG_MMU_INVLD_PA);
180         regval = readl_relaxed(data->base + REG_MMU_INT_ID);
181         fault_larb = MT2701_M4U_TF_LARB(regval);
182         fault_port = MT2701_M4U_TF_PORT(regval);
183
184         /*
185          * MTK v1 iommu HW could not determine whether the fault is read or
186          * write fault, report as read fault.
187          */
188         if (report_iommu_fault(&dom->domain, data->dev, fault_iova,
189                         IOMMU_FAULT_READ))
190                 dev_err_ratelimited(data->dev,
191                         "fault type=0x%x iova=0x%x pa=0x%x larb=%d port=%d\n",
192                         int_state, fault_iova, fault_pa,
193                         fault_larb, fault_port);
194
195         /* Interrupt clear */
196         regval = readl_relaxed(data->base + REG_MMU_INT_CONTROL);
197         regval |= F_INT_CLR_BIT;
198         writel_relaxed(regval, data->base + REG_MMU_INT_CONTROL);
199
200         mtk_iommu_tlb_flush_all(data);
201
202         return IRQ_HANDLED;
203 }
204
205 static void mtk_iommu_config(struct mtk_iommu_data *data,
206                              struct device *dev, bool enable)
207 {
208         struct mtk_smi_larb_iommu    *larb_mmu;
209         unsigned int                 larbid, portid;
210         struct iommu_fwspec *fwspec = dev->iommu_fwspec;
211         int i;
212
213         for (i = 0; i < fwspec->num_ids; ++i) {
214                 larbid = mt2701_m4u_to_larb(fwspec->ids[i]);
215                 portid = mt2701_m4u_to_port(fwspec->ids[i]);
216                 larb_mmu = &data->smi_imu.larb_imu[larbid];
217
218                 dev_dbg(dev, "%s iommu port: %d\n",
219                         enable ? "enable" : "disable", portid);
220
221                 if (enable)
222                         larb_mmu->mmu |= MTK_SMI_MMU_EN(portid);
223                 else
224                         larb_mmu->mmu &= ~MTK_SMI_MMU_EN(portid);
225         }
226 }
227
228 static int mtk_iommu_domain_finalise(struct mtk_iommu_data *data)
229 {
230         struct mtk_iommu_domain *dom = data->m4u_dom;
231
232         spin_lock_init(&dom->pgtlock);
233
234         dom->pgt_va = dma_zalloc_coherent(data->dev,
235                                 M2701_IOMMU_PGT_SIZE,
236                                 &dom->pgt_pa, GFP_KERNEL);
237         if (!dom->pgt_va)
238                 return -ENOMEM;
239
240         writel(dom->pgt_pa, data->base + REG_MMU_PT_BASE_ADDR);
241
242         dom->data = data;
243
244         return 0;
245 }
246
247 static struct iommu_domain *mtk_iommu_domain_alloc(unsigned type)
248 {
249         struct mtk_iommu_domain *dom;
250
251         if (type != IOMMU_DOMAIN_UNMANAGED)
252                 return NULL;
253
254         dom = kzalloc(sizeof(*dom), GFP_KERNEL);
255         if (!dom)
256                 return NULL;
257
258         return &dom->domain;
259 }
260
261 static void mtk_iommu_domain_free(struct iommu_domain *domain)
262 {
263         struct mtk_iommu_domain *dom = to_mtk_domain(domain);
264         struct mtk_iommu_data *data = dom->data;
265
266         dma_free_coherent(data->dev, M2701_IOMMU_PGT_SIZE,
267                         dom->pgt_va, dom->pgt_pa);
268         kfree(to_mtk_domain(domain));
269 }
270
271 static int mtk_iommu_attach_device(struct iommu_domain *domain,
272                                    struct device *dev)
273 {
274         struct mtk_iommu_domain *dom = to_mtk_domain(domain);
275         struct mtk_iommu_data *data = dev->iommu_fwspec->iommu_priv;
276         int ret;
277
278         if (!data)
279                 return -ENODEV;
280
281         if (!data->m4u_dom) {
282                 data->m4u_dom = dom;
283                 ret = mtk_iommu_domain_finalise(data);
284                 if (ret) {
285                         data->m4u_dom = NULL;
286                         return ret;
287                 }
288         }
289
290         mtk_iommu_config(data, dev, true);
291         return 0;
292 }
293
294 static void mtk_iommu_detach_device(struct iommu_domain *domain,
295                                     struct device *dev)
296 {
297         struct mtk_iommu_data *data = dev->iommu_fwspec->iommu_priv;
298
299         if (!data)
300                 return;
301
302         mtk_iommu_config(data, dev, false);
303 }
304
305 static int mtk_iommu_map(struct iommu_domain *domain, unsigned long iova,
306                          phys_addr_t paddr, size_t size, int prot)
307 {
308         struct mtk_iommu_domain *dom = to_mtk_domain(domain);
309         unsigned int page_num = size >> MT2701_IOMMU_PAGE_SHIFT;
310         unsigned long flags;
311         unsigned int i;
312         u32 *pgt_base_iova = dom->pgt_va + (iova  >> MT2701_IOMMU_PAGE_SHIFT);
313         u32 pabase = (u32)paddr;
314         int map_size = 0;
315
316         spin_lock_irqsave(&dom->pgtlock, flags);
317         for (i = 0; i < page_num; i++) {
318                 if (pgt_base_iova[i]) {
319                         memset(pgt_base_iova, 0, i * sizeof(u32));
320                         break;
321                 }
322                 pgt_base_iova[i] = pabase | F_DESC_VALID | F_DESC_NONSEC;
323                 pabase += MT2701_IOMMU_PAGE_SIZE;
324                 map_size += MT2701_IOMMU_PAGE_SIZE;
325         }
326
327         spin_unlock_irqrestore(&dom->pgtlock, flags);
328
329         mtk_iommu_tlb_flush_range(dom->data, iova, size);
330
331         return map_size == size ? 0 : -EEXIST;
332 }
333
334 static size_t mtk_iommu_unmap(struct iommu_domain *domain,
335                               unsigned long iova, size_t size)
336 {
337         struct mtk_iommu_domain *dom = to_mtk_domain(domain);
338         unsigned long flags;
339         u32 *pgt_base_iova = dom->pgt_va + (iova  >> MT2701_IOMMU_PAGE_SHIFT);
340         unsigned int page_num = size >> MT2701_IOMMU_PAGE_SHIFT;
341
342         spin_lock_irqsave(&dom->pgtlock, flags);
343         memset(pgt_base_iova, 0, page_num * sizeof(u32));
344         spin_unlock_irqrestore(&dom->pgtlock, flags);
345
346         mtk_iommu_tlb_flush_range(dom->data, iova, size);
347
348         return size;
349 }
350
351 static phys_addr_t mtk_iommu_iova_to_phys(struct iommu_domain *domain,
352                                           dma_addr_t iova)
353 {
354         struct mtk_iommu_domain *dom = to_mtk_domain(domain);
355         unsigned long flags;
356         phys_addr_t pa;
357
358         spin_lock_irqsave(&dom->pgtlock, flags);
359         pa = *(dom->pgt_va + (iova >> MT2701_IOMMU_PAGE_SHIFT));
360         pa = pa & (~(MT2701_IOMMU_PAGE_SIZE - 1));
361         spin_unlock_irqrestore(&dom->pgtlock, flags);
362
363         return pa;
364 }
365
366 static struct iommu_ops mtk_iommu_ops;
367
368 /*
369  * MTK generation one iommu HW only support one iommu domain, and all the client
370  * sharing the same iova address space.
371  */
372 static int mtk_iommu_create_mapping(struct device *dev,
373                                     struct of_phandle_args *args)
374 {
375         struct mtk_iommu_data *data;
376         struct platform_device *m4updev;
377         struct dma_iommu_mapping *mtk_mapping;
378         struct device *m4udev;
379         int ret;
380
381         if (args->args_count != 1) {
382                 dev_err(dev, "invalid #iommu-cells(%d) property for IOMMU\n",
383                         args->args_count);
384                 return -EINVAL;
385         }
386
387         if (!dev->iommu_fwspec) {
388                 ret = iommu_fwspec_init(dev, &args->np->fwnode, &mtk_iommu_ops);
389                 if (ret)
390                         return ret;
391         } else if (dev->iommu_fwspec->ops != &mtk_iommu_ops) {
392                 return -EINVAL;
393         }
394
395         if (!dev->iommu_fwspec->iommu_priv) {
396                 /* Get the m4u device */
397                 m4updev = of_find_device_by_node(args->np);
398                 if (WARN_ON(!m4updev))
399                         return -EINVAL;
400
401                 dev->iommu_fwspec->iommu_priv = platform_get_drvdata(m4updev);
402         }
403
404         ret = iommu_fwspec_add_ids(dev, args->args, 1);
405         if (ret)
406                 return ret;
407
408         data = dev->iommu_fwspec->iommu_priv;
409         m4udev = data->dev;
410         mtk_mapping = m4udev->archdata.iommu;
411         if (!mtk_mapping) {
412                 /* MTK iommu support 4GB iova address space. */
413                 mtk_mapping = arm_iommu_create_mapping(&platform_bus_type,
414                                                 0, 1ULL << 32);
415                 if (IS_ERR(mtk_mapping))
416                         return PTR_ERR(mtk_mapping);
417
418                 m4udev->archdata.iommu = mtk_mapping;
419         }
420
421         ret = arm_iommu_attach_device(dev, mtk_mapping);
422         if (ret)
423                 goto err_release_mapping;
424
425         return 0;
426
427 err_release_mapping:
428         arm_iommu_release_mapping(mtk_mapping);
429         m4udev->archdata.iommu = NULL;
430         return ret;
431 }
432
433 static int mtk_iommu_add_device(struct device *dev)
434 {
435         struct of_phandle_args iommu_spec;
436         struct of_phandle_iterator it;
437         struct mtk_iommu_data *data;
438         struct iommu_group *group;
439         int err;
440
441         of_for_each_phandle(&it, err, dev->of_node, "iommus",
442                         "#iommu-cells", 0) {
443                 int count = of_phandle_iterator_args(&it, iommu_spec.args,
444                                         MAX_PHANDLE_ARGS);
445                 iommu_spec.np = of_node_get(it.node);
446                 iommu_spec.args_count = count;
447
448                 mtk_iommu_create_mapping(dev, &iommu_spec);
449                 of_node_put(iommu_spec.np);
450         }
451
452         if (!dev->iommu_fwspec || dev->iommu_fwspec->ops != &mtk_iommu_ops)
453                 return -ENODEV; /* Not a iommu client device */
454
455         data = dev->iommu_fwspec->iommu_priv;
456         iommu_device_link(&data->iommu, dev);
457
458         group = iommu_group_get_for_dev(dev);
459         if (IS_ERR(group))
460                 return PTR_ERR(group);
461
462         iommu_group_put(group);
463         return 0;
464 }
465
466 static void mtk_iommu_remove_device(struct device *dev)
467 {
468         struct mtk_iommu_data *data;
469
470         if (!dev->iommu_fwspec || dev->iommu_fwspec->ops != &mtk_iommu_ops)
471                 return;
472
473         data = dev->iommu_fwspec->iommu_priv;
474         iommu_device_unlink(&data->iommu, dev);
475
476         iommu_group_remove_device(dev);
477         iommu_fwspec_free(dev);
478 }
479
480 static struct iommu_group *mtk_iommu_device_group(struct device *dev)
481 {
482         struct mtk_iommu_data *data = dev->iommu_fwspec->iommu_priv;
483
484         if (!data)
485                 return ERR_PTR(-ENODEV);
486
487         /* All the client devices are in the same m4u iommu-group */
488         if (!data->m4u_group) {
489                 data->m4u_group = iommu_group_alloc();
490                 if (IS_ERR(data->m4u_group))
491                         dev_err(dev, "Failed to allocate M4U IOMMU group\n");
492         } else {
493                 iommu_group_ref_get(data->m4u_group);
494         }
495         return data->m4u_group;
496 }
497
498 static int mtk_iommu_hw_init(const struct mtk_iommu_data *data)
499 {
500         u32 regval;
501         int ret;
502
503         ret = clk_prepare_enable(data->bclk);
504         if (ret) {
505                 dev_err(data->dev, "Failed to enable iommu bclk(%d)\n", ret);
506                 return ret;
507         }
508
509         regval = F_MMU_CTRL_COHERENT_EN | F_MMU_TF_PROTECT_SEL(2);
510         writel_relaxed(regval, data->base + REG_MMU_CTRL_REG);
511
512         regval = F_INT_TRANSLATION_FAULT |
513                 F_INT_MAIN_MULTI_HIT_FAULT |
514                 F_INT_INVALID_PA_FAULT |
515                 F_INT_ENTRY_REPLACEMENT_FAULT |
516                 F_INT_TABLE_WALK_FAULT |
517                 F_INT_TLB_MISS_FAULT |
518                 F_INT_PFH_DMA_FIFO_OVERFLOW |
519                 F_INT_MISS_DMA_FIFO_OVERFLOW;
520         writel_relaxed(regval, data->base + REG_MMU_INT_CONTROL);
521
522         /* protect memory,hw will write here while translation fault */
523         writel_relaxed(data->protect_base,
524                         data->base + REG_MMU_IVRP_PADDR);
525
526         writel_relaxed(F_MMU_DCM_ON, data->base + REG_MMU_DCM);
527
528         if (devm_request_irq(data->dev, data->irq, mtk_iommu_isr, 0,
529                              dev_name(data->dev), (void *)data)) {
530                 writel_relaxed(0, data->base + REG_MMU_PT_BASE_ADDR);
531                 clk_disable_unprepare(data->bclk);
532                 dev_err(data->dev, "Failed @ IRQ-%d Request\n", data->irq);
533                 return -ENODEV;
534         }
535
536         return 0;
537 }
538
539 static struct iommu_ops mtk_iommu_ops = {
540         .domain_alloc   = mtk_iommu_domain_alloc,
541         .domain_free    = mtk_iommu_domain_free,
542         .attach_dev     = mtk_iommu_attach_device,
543         .detach_dev     = mtk_iommu_detach_device,
544         .map            = mtk_iommu_map,
545         .unmap          = mtk_iommu_unmap,
546         .map_sg         = default_iommu_map_sg,
547         .iova_to_phys   = mtk_iommu_iova_to_phys,
548         .add_device     = mtk_iommu_add_device,
549         .remove_device  = mtk_iommu_remove_device,
550         .device_group   = mtk_iommu_device_group,
551         .pgsize_bitmap  = ~0UL << MT2701_IOMMU_PAGE_SHIFT,
552 };
553
554 static const struct of_device_id mtk_iommu_of_ids[] = {
555         { .compatible = "mediatek,mt2701-m4u", },
556         {}
557 };
558
559 static const struct component_master_ops mtk_iommu_com_ops = {
560         .bind           = mtk_iommu_bind,
561         .unbind         = mtk_iommu_unbind,
562 };
563
564 static int mtk_iommu_probe(struct platform_device *pdev)
565 {
566         struct mtk_iommu_data           *data;
567         struct device                   *dev = &pdev->dev;
568         struct resource                 *res;
569         struct component_match          *match = NULL;
570         struct of_phandle_args          larb_spec;
571         struct of_phandle_iterator      it;
572         void                            *protect;
573         int                             larb_nr, ret, err;
574
575         data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
576         if (!data)
577                 return -ENOMEM;
578
579         data->dev = dev;
580
581         /* Protect memory. HW will access here while translation fault.*/
582         protect = devm_kzalloc(dev, MTK_PROTECT_PA_ALIGN * 2,
583                         GFP_KERNEL | GFP_DMA);
584         if (!protect)
585                 return -ENOMEM;
586         data->protect_base = ALIGN(virt_to_phys(protect), MTK_PROTECT_PA_ALIGN);
587
588         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
589         data->base = devm_ioremap_resource(dev, res);
590         if (IS_ERR(data->base))
591                 return PTR_ERR(data->base);
592
593         data->irq = platform_get_irq(pdev, 0);
594         if (data->irq < 0)
595                 return data->irq;
596
597         data->bclk = devm_clk_get(dev, "bclk");
598         if (IS_ERR(data->bclk))
599                 return PTR_ERR(data->bclk);
600
601         larb_nr = 0;
602         of_for_each_phandle(&it, err, dev->of_node,
603                         "mediatek,larbs", NULL, 0) {
604                 struct platform_device *plarbdev;
605                 int count = of_phandle_iterator_args(&it, larb_spec.args,
606                                         MAX_PHANDLE_ARGS);
607
608                 if (count)
609                         continue;
610
611                 larb_spec.np = of_node_get(it.node);
612                 if (!of_device_is_available(larb_spec.np))
613                         continue;
614
615                 plarbdev = of_find_device_by_node(larb_spec.np);
616                 if (!plarbdev) {
617                         plarbdev = of_platform_device_create(
618                                                 larb_spec.np, NULL,
619                                                 platform_bus_type.dev_root);
620                         if (!plarbdev) {
621                                 of_node_put(larb_spec.np);
622                                 return -EPROBE_DEFER;
623                         }
624                 }
625
626                 data->smi_imu.larb_imu[larb_nr].dev = &plarbdev->dev;
627                 component_match_add_release(dev, &match, release_of,
628                                             compare_of, larb_spec.np);
629                 larb_nr++;
630         }
631
632         data->smi_imu.larb_nr = larb_nr;
633
634         platform_set_drvdata(pdev, data);
635
636         ret = mtk_iommu_hw_init(data);
637         if (ret)
638                 return ret;
639
640         ret = iommu_device_sysfs_add(&data->iommu, &pdev->dev, NULL,
641                                      dev_name(&pdev->dev));
642         if (ret)
643                 return ret;
644
645         iommu_device_set_ops(&data->iommu, &mtk_iommu_ops);
646
647         ret = iommu_device_register(&data->iommu);
648         if (ret)
649                 return ret;
650
651         if (!iommu_present(&platform_bus_type))
652                 bus_set_iommu(&platform_bus_type,  &mtk_iommu_ops);
653
654         return component_master_add_with_match(dev, &mtk_iommu_com_ops, match);
655 }
656
657 static int mtk_iommu_remove(struct platform_device *pdev)
658 {
659         struct mtk_iommu_data *data = platform_get_drvdata(pdev);
660
661         iommu_device_sysfs_remove(&data->iommu);
662         iommu_device_unregister(&data->iommu);
663
664         if (iommu_present(&platform_bus_type))
665                 bus_set_iommu(&platform_bus_type, NULL);
666
667         clk_disable_unprepare(data->bclk);
668         devm_free_irq(&pdev->dev, data->irq, data);
669         component_master_del(&pdev->dev, &mtk_iommu_com_ops);
670         return 0;
671 }
672
673 static int __maybe_unused mtk_iommu_suspend(struct device *dev)
674 {
675         struct mtk_iommu_data *data = dev_get_drvdata(dev);
676         struct mtk_iommu_suspend_reg *reg = &data->reg;
677         void __iomem *base = data->base;
678
679         reg->standard_axi_mode = readl_relaxed(base +
680                                                REG_MMU_STANDARD_AXI_MODE);
681         reg->dcm_dis = readl_relaxed(base + REG_MMU_DCM);
682         reg->ctrl_reg = readl_relaxed(base + REG_MMU_CTRL_REG);
683         reg->int_control0 = readl_relaxed(base + REG_MMU_INT_CONTROL);
684         return 0;
685 }
686
687 static int __maybe_unused mtk_iommu_resume(struct device *dev)
688 {
689         struct mtk_iommu_data *data = dev_get_drvdata(dev);
690         struct mtk_iommu_suspend_reg *reg = &data->reg;
691         void __iomem *base = data->base;
692
693         writel_relaxed(data->m4u_dom->pgt_pa, base + REG_MMU_PT_BASE_ADDR);
694         writel_relaxed(reg->standard_axi_mode,
695                        base + REG_MMU_STANDARD_AXI_MODE);
696         writel_relaxed(reg->dcm_dis, base + REG_MMU_DCM);
697         writel_relaxed(reg->ctrl_reg, base + REG_MMU_CTRL_REG);
698         writel_relaxed(reg->int_control0, base + REG_MMU_INT_CONTROL);
699         writel_relaxed(data->protect_base, base + REG_MMU_IVRP_PADDR);
700         return 0;
701 }
702
703 static const struct dev_pm_ops mtk_iommu_pm_ops = {
704         SET_SYSTEM_SLEEP_PM_OPS(mtk_iommu_suspend, mtk_iommu_resume)
705 };
706
707 static struct platform_driver mtk_iommu_driver = {
708         .probe  = mtk_iommu_probe,
709         .remove = mtk_iommu_remove,
710         .driver = {
711                 .name = "mtk-iommu",
712                 .of_match_table = mtk_iommu_of_ids,
713                 .pm = &mtk_iommu_pm_ops,
714         }
715 };
716
717 static int __init m4u_init(void)
718 {
719         return platform_driver_register(&mtk_iommu_driver);
720 }
721
722 static void __exit m4u_exit(void)
723 {
724         return platform_driver_unregister(&mtk_iommu_driver);
725 }
726
727 subsys_initcall(m4u_init);
728 module_exit(m4u_exit);
729
730 MODULE_DESCRIPTION("IOMMU API for MTK architected m4u v1 implementations");
731 MODULE_AUTHOR("Honghui Zhang <honghui.zhang@mediatek.com>");
732 MODULE_LICENSE("GPL v2");