linux/drivers/iommu/mtk_iommu_v1.c
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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * IOMMU API for MTK architected m4u v1 implementations
   4 *
   5 * Copyright (c) 2015-2016 MediaTek Inc.
   6 * Author: Honghui Zhang <honghui.zhang@mediatek.com>
   7 *
   8 * Based on driver/iommu/mtk_iommu.c
   9 */
  10#include <linux/memblock.h>
  11#include <linux/bug.h>
  12#include <linux/clk.h>
  13#include <linux/component.h>
  14#include <linux/device.h>
  15#include <linux/dma-mapping.h>
  16#include <linux/dma-iommu.h>
  17#include <linux/err.h>
  18#include <linux/interrupt.h>
  19#include <linux/io.h>
  20#include <linux/iommu.h>
  21#include <linux/iopoll.h>
  22#include <linux/list.h>
  23#include <linux/of_address.h>
  24#include <linux/of_iommu.h>
  25#include <linux/of_irq.h>
  26#include <linux/of_platform.h>
  27#include <linux/platform_device.h>
  28#include <linux/slab.h>
  29#include <linux/spinlock.h>
  30#include <asm/barrier.h>
  31#include <asm/dma-iommu.h>
  32#include <linux/init.h>
  33#include <dt-bindings/memory/mt2701-larb-port.h>
  34#include <soc/mediatek/smi.h>
  35#include "mtk_iommu.h"
  36
  37#define REG_MMU_PT_BASE_ADDR                    0x000
  38
  39#define F_ALL_INVLD                             0x2
  40#define F_MMU_INV_RANGE                         0x1
  41#define F_INVLD_EN0                             BIT(0)
  42#define F_INVLD_EN1                             BIT(1)
  43
  44#define F_MMU_FAULT_VA_MSK                      0xfffff000
  45#define MTK_PROTECT_PA_ALIGN                    128
  46
  47#define REG_MMU_CTRL_REG                        0x210
  48#define F_MMU_CTRL_COHERENT_EN                  BIT(8)
  49#define REG_MMU_IVRP_PADDR                      0x214
  50#define REG_MMU_INT_CONTROL                     0x220
  51#define F_INT_TRANSLATION_FAULT                 BIT(0)
  52#define F_INT_MAIN_MULTI_HIT_FAULT              BIT(1)
  53#define F_INT_INVALID_PA_FAULT                  BIT(2)
  54#define F_INT_ENTRY_REPLACEMENT_FAULT           BIT(3)
  55#define F_INT_TABLE_WALK_FAULT                  BIT(4)
  56#define F_INT_TLB_MISS_FAULT                    BIT(5)
  57#define F_INT_PFH_DMA_FIFO_OVERFLOW             BIT(6)
  58#define F_INT_MISS_DMA_FIFO_OVERFLOW            BIT(7)
  59
  60#define F_MMU_TF_PROTECT_SEL(prot)              (((prot) & 0x3) << 5)
  61#define F_INT_CLR_BIT                           BIT(12)
  62
  63#define REG_MMU_FAULT_ST                        0x224
  64#define REG_MMU_FAULT_VA                        0x228
  65#define REG_MMU_INVLD_PA                        0x22C
  66#define REG_MMU_INT_ID                          0x388
  67#define REG_MMU_INVALIDATE                      0x5c0
  68#define REG_MMU_INVLD_START_A                   0x5c4
  69#define REG_MMU_INVLD_END_A                     0x5c8
  70
  71#define REG_MMU_INV_SEL                         0x5d8
  72#define REG_MMU_STANDARD_AXI_MODE               0x5e8
  73
  74#define REG_MMU_DCM                             0x5f0
  75#define F_MMU_DCM_ON                            BIT(1)
  76#define REG_MMU_CPE_DONE                        0x60c
  77#define F_DESC_VALID                            0x2
  78#define F_DESC_NONSEC                           BIT(3)
  79#define MT2701_M4U_TF_LARB(TF)                  (6 - (((TF) >> 13) & 0x7))
  80#define MT2701_M4U_TF_PORT(TF)                  (((TF) >> 8) & 0xF)
  81/* MTK generation one iommu HW only support 4K size mapping */
  82#define MT2701_IOMMU_PAGE_SHIFT                 12
  83#define MT2701_IOMMU_PAGE_SIZE                  (1UL << MT2701_IOMMU_PAGE_SHIFT)
  84
  85/*
  86 * MTK m4u support 4GB iova address space, and only support 4K page
  87 * mapping. So the pagetable size should be exactly as 4M.
  88 */
  89#define M2701_IOMMU_PGT_SIZE                    SZ_4M
  90
  91struct mtk_iommu_domain {
  92        spinlock_t                      pgtlock; /* lock for page table */
  93        struct iommu_domain             domain;
  94        u32                             *pgt_va;
  95        dma_addr_t                      pgt_pa;
  96        struct mtk_iommu_data           *data;
  97};
  98
  99static struct mtk_iommu_domain *to_mtk_domain(struct iommu_domain *dom)
 100{
 101        return container_of(dom, struct mtk_iommu_domain, domain);
 102}
 103
 104static const int mt2701_m4u_in_larb[] = {
 105        LARB0_PORT_OFFSET, LARB1_PORT_OFFSET,
 106        LARB2_PORT_OFFSET, LARB3_PORT_OFFSET
 107};
 108
 109static inline int mt2701_m4u_to_larb(int id)
 110{
 111        int i;
 112
 113        for (i = ARRAY_SIZE(mt2701_m4u_in_larb) - 1; i >= 0; i--)
 114                if ((id) >= mt2701_m4u_in_larb[i])
 115                        return i;
 116
 117        return 0;
 118}
 119
 120static inline int mt2701_m4u_to_port(int id)
 121{
 122        int larb = mt2701_m4u_to_larb(id);
 123
 124        return id - mt2701_m4u_in_larb[larb];
 125}
 126
 127static void mtk_iommu_tlb_flush_all(struct mtk_iommu_data *data)
 128{
 129        writel_relaxed(F_INVLD_EN1 | F_INVLD_EN0,
 130                        data->base + REG_MMU_INV_SEL);
 131        writel_relaxed(F_ALL_INVLD, data->base + REG_MMU_INVALIDATE);
 132        wmb(); /* Make sure the tlb flush all done */
 133}
 134
 135static void mtk_iommu_tlb_flush_range(struct mtk_iommu_data *data,
 136                                unsigned long iova, size_t size)
 137{
 138        int ret;
 139        u32 tmp;
 140
 141        writel_relaxed(F_INVLD_EN1 | F_INVLD_EN0,
 142                data->base + REG_MMU_INV_SEL);
 143        writel_relaxed(iova & F_MMU_FAULT_VA_MSK,
 144                data->base + REG_MMU_INVLD_START_A);
 145        writel_relaxed((iova + size - 1) & F_MMU_FAULT_VA_MSK,
 146                data->base + REG_MMU_INVLD_END_A);
 147        writel_relaxed(F_MMU_INV_RANGE, data->base + REG_MMU_INVALIDATE);
 148
 149        ret = readl_poll_timeout_atomic(data->base + REG_MMU_CPE_DONE,
 150                                tmp, tmp != 0, 10, 100000);
 151        if (ret) {
 152                dev_warn(data->dev,
 153                         "Partial TLB flush timed out, falling back to full flush\n");
 154                mtk_iommu_tlb_flush_all(data);
 155        }
 156        /* Clear the CPE status */
 157        writel_relaxed(0, data->base + REG_MMU_CPE_DONE);
 158}
 159
 160static irqreturn_t mtk_iommu_isr(int irq, void *dev_id)
 161{
 162        struct mtk_iommu_data *data = dev_id;
 163        struct mtk_iommu_domain *dom = data->m4u_dom;
 164        u32 int_state, regval, fault_iova, fault_pa;
 165        unsigned int fault_larb, fault_port;
 166
 167        /* Read error information from registers */
 168        int_state = readl_relaxed(data->base + REG_MMU_FAULT_ST);
 169        fault_iova = readl_relaxed(data->base + REG_MMU_FAULT_VA);
 170
 171        fault_iova &= F_MMU_FAULT_VA_MSK;
 172        fault_pa = readl_relaxed(data->base + REG_MMU_INVLD_PA);
 173        regval = readl_relaxed(data->base + REG_MMU_INT_ID);
 174        fault_larb = MT2701_M4U_TF_LARB(regval);
 175        fault_port = MT2701_M4U_TF_PORT(regval);
 176
 177        /*
 178         * MTK v1 iommu HW could not determine whether the fault is read or
 179         * write fault, report as read fault.
 180         */
 181        if (report_iommu_fault(&dom->domain, data->dev, fault_iova,
 182                        IOMMU_FAULT_READ))
 183                dev_err_ratelimited(data->dev,
 184                        "fault type=0x%x iova=0x%x pa=0x%x larb=%d port=%d\n",
 185                        int_state, fault_iova, fault_pa,
 186                        fault_larb, fault_port);
 187
 188        /* Interrupt clear */
 189        regval = readl_relaxed(data->base + REG_MMU_INT_CONTROL);
 190        regval |= F_INT_CLR_BIT;
 191        writel_relaxed(regval, data->base + REG_MMU_INT_CONTROL);
 192
 193        mtk_iommu_tlb_flush_all(data);
 194
 195        return IRQ_HANDLED;
 196}
 197
 198static void mtk_iommu_config(struct mtk_iommu_data *data,
 199                             struct device *dev, bool enable)
 200{
 201        struct mtk_smi_larb_iommu    *larb_mmu;
 202        unsigned int                 larbid, portid;
 203        struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
 204        int i;
 205
 206        for (i = 0; i < fwspec->num_ids; ++i) {
 207                larbid = mt2701_m4u_to_larb(fwspec->ids[i]);
 208                portid = mt2701_m4u_to_port(fwspec->ids[i]);
 209                larb_mmu = &data->larb_imu[larbid];
 210
 211                dev_dbg(dev, "%s iommu port: %d\n",
 212                        enable ? "enable" : "disable", portid);
 213
 214                if (enable)
 215                        larb_mmu->mmu |= MTK_SMI_MMU_EN(portid);
 216                else
 217                        larb_mmu->mmu &= ~MTK_SMI_MMU_EN(portid);
 218        }
 219}
 220
 221static int mtk_iommu_domain_finalise(struct mtk_iommu_data *data)
 222{
 223        struct mtk_iommu_domain *dom = data->m4u_dom;
 224
 225        spin_lock_init(&dom->pgtlock);
 226
 227        dom->pgt_va = dma_alloc_coherent(data->dev, M2701_IOMMU_PGT_SIZE,
 228                                         &dom->pgt_pa, GFP_KERNEL);
 229        if (!dom->pgt_va)
 230                return -ENOMEM;
 231
 232        writel(dom->pgt_pa, data->base + REG_MMU_PT_BASE_ADDR);
 233
 234        dom->data = data;
 235
 236        return 0;
 237}
 238
 239static struct iommu_domain *mtk_iommu_domain_alloc(unsigned type)
 240{
 241        struct mtk_iommu_domain *dom;
 242
 243        if (type != IOMMU_DOMAIN_UNMANAGED)
 244                return NULL;
 245
 246        dom = kzalloc(sizeof(*dom), GFP_KERNEL);
 247        if (!dom)
 248                return NULL;
 249
 250        return &dom->domain;
 251}
 252
 253static void mtk_iommu_domain_free(struct iommu_domain *domain)
 254{
 255        struct mtk_iommu_domain *dom = to_mtk_domain(domain);
 256        struct mtk_iommu_data *data = dom->data;
 257
 258        dma_free_coherent(data->dev, M2701_IOMMU_PGT_SIZE,
 259                        dom->pgt_va, dom->pgt_pa);
 260        kfree(to_mtk_domain(domain));
 261}
 262
 263static int mtk_iommu_attach_device(struct iommu_domain *domain,
 264                                   struct device *dev)
 265{
 266        struct mtk_iommu_data *data = dev_iommu_priv_get(dev);
 267        struct mtk_iommu_domain *dom = to_mtk_domain(domain);
 268        struct dma_iommu_mapping *mtk_mapping;
 269        int ret;
 270
 271        /* Only allow the domain created internally. */
 272        mtk_mapping = data->mapping;
 273        if (mtk_mapping->domain != domain)
 274                return 0;
 275
 276        if (!data->m4u_dom) {
 277                data->m4u_dom = dom;
 278                ret = mtk_iommu_domain_finalise(data);
 279                if (ret) {
 280                        data->m4u_dom = NULL;
 281                        return ret;
 282                }
 283        }
 284
 285        mtk_iommu_config(data, dev, true);
 286        return 0;
 287}
 288
 289static void mtk_iommu_detach_device(struct iommu_domain *domain,
 290                                    struct device *dev)
 291{
 292        struct mtk_iommu_data *data = dev_iommu_priv_get(dev);
 293
 294        mtk_iommu_config(data, dev, false);
 295}
 296
 297static int mtk_iommu_map(struct iommu_domain *domain, unsigned long iova,
 298                         phys_addr_t paddr, size_t size, int prot, gfp_t gfp)
 299{
 300        struct mtk_iommu_domain *dom = to_mtk_domain(domain);
 301        unsigned int page_num = size >> MT2701_IOMMU_PAGE_SHIFT;
 302        unsigned long flags;
 303        unsigned int i;
 304        u32 *pgt_base_iova = dom->pgt_va + (iova  >> MT2701_IOMMU_PAGE_SHIFT);
 305        u32 pabase = (u32)paddr;
 306        int map_size = 0;
 307
 308        spin_lock_irqsave(&dom->pgtlock, flags);
 309        for (i = 0; i < page_num; i++) {
 310                if (pgt_base_iova[i]) {
 311                        memset(pgt_base_iova, 0, i * sizeof(u32));
 312                        break;
 313                }
 314                pgt_base_iova[i] = pabase | F_DESC_VALID | F_DESC_NONSEC;
 315                pabase += MT2701_IOMMU_PAGE_SIZE;
 316                map_size += MT2701_IOMMU_PAGE_SIZE;
 317        }
 318
 319        spin_unlock_irqrestore(&dom->pgtlock, flags);
 320
 321        mtk_iommu_tlb_flush_range(dom->data, iova, size);
 322
 323        return map_size == size ? 0 : -EEXIST;
 324}
 325
 326static size_t mtk_iommu_unmap(struct iommu_domain *domain,
 327                              unsigned long iova, size_t size,
 328                              struct iommu_iotlb_gather *gather)
 329{
 330        struct mtk_iommu_domain *dom = to_mtk_domain(domain);
 331        unsigned long flags;
 332        u32 *pgt_base_iova = dom->pgt_va + (iova  >> MT2701_IOMMU_PAGE_SHIFT);
 333        unsigned int page_num = size >> MT2701_IOMMU_PAGE_SHIFT;
 334
 335        spin_lock_irqsave(&dom->pgtlock, flags);
 336        memset(pgt_base_iova, 0, page_num * sizeof(u32));
 337        spin_unlock_irqrestore(&dom->pgtlock, flags);
 338
 339        mtk_iommu_tlb_flush_range(dom->data, iova, size);
 340
 341        return size;
 342}
 343
 344static phys_addr_t mtk_iommu_iova_to_phys(struct iommu_domain *domain,
 345                                          dma_addr_t iova)
 346{
 347        struct mtk_iommu_domain *dom = to_mtk_domain(domain);
 348        unsigned long flags;
 349        phys_addr_t pa;
 350
 351        spin_lock_irqsave(&dom->pgtlock, flags);
 352        pa = *(dom->pgt_va + (iova >> MT2701_IOMMU_PAGE_SHIFT));
 353        pa = pa & (~(MT2701_IOMMU_PAGE_SIZE - 1));
 354        spin_unlock_irqrestore(&dom->pgtlock, flags);
 355
 356        return pa;
 357}
 358
 359static const struct iommu_ops mtk_iommu_ops;
 360
 361/*
 362 * MTK generation one iommu HW only support one iommu domain, and all the client
 363 * sharing the same iova address space.
 364 */
 365static int mtk_iommu_create_mapping(struct device *dev,
 366                                    struct of_phandle_args *args)
 367{
 368        struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
 369        struct mtk_iommu_data *data;
 370        struct platform_device *m4updev;
 371        struct dma_iommu_mapping *mtk_mapping;
 372        int ret;
 373
 374        if (args->args_count != 1) {
 375                dev_err(dev, "invalid #iommu-cells(%d) property for IOMMU\n",
 376                        args->args_count);
 377                return -EINVAL;
 378        }
 379
 380        if (!fwspec) {
 381                ret = iommu_fwspec_init(dev, &args->np->fwnode, &mtk_iommu_ops);
 382                if (ret)
 383                        return ret;
 384                fwspec = dev_iommu_fwspec_get(dev);
 385        } else if (dev_iommu_fwspec_get(dev)->ops != &mtk_iommu_ops) {
 386                return -EINVAL;
 387        }
 388
 389        if (!dev_iommu_priv_get(dev)) {
 390                /* Get the m4u device */
 391                m4updev = of_find_device_by_node(args->np);
 392                if (WARN_ON(!m4updev))
 393                        return -EINVAL;
 394
 395                dev_iommu_priv_set(dev, platform_get_drvdata(m4updev));
 396        }
 397
 398        ret = iommu_fwspec_add_ids(dev, args->args, 1);
 399        if (ret)
 400                return ret;
 401
 402        data = dev_iommu_priv_get(dev);
 403        mtk_mapping = data->mapping;
 404        if (!mtk_mapping) {
 405                /* MTK iommu support 4GB iova address space. */
 406                mtk_mapping = arm_iommu_create_mapping(&platform_bus_type,
 407                                                0, 1ULL << 32);
 408                if (IS_ERR(mtk_mapping))
 409                        return PTR_ERR(mtk_mapping);
 410
 411                data->mapping = mtk_mapping;
 412        }
 413
 414        return 0;
 415}
 416
 417static int mtk_iommu_def_domain_type(struct device *dev)
 418{
 419        return IOMMU_DOMAIN_UNMANAGED;
 420}
 421
 422static struct iommu_device *mtk_iommu_probe_device(struct device *dev)
 423{
 424        struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
 425        struct of_phandle_args iommu_spec;
 426        struct of_phandle_iterator it;
 427        struct mtk_iommu_data *data;
 428        int err;
 429
 430        of_for_each_phandle(&it, err, dev->of_node, "iommus",
 431                        "#iommu-cells", -1) {
 432                int count = of_phandle_iterator_args(&it, iommu_spec.args,
 433                                        MAX_PHANDLE_ARGS);
 434                iommu_spec.np = of_node_get(it.node);
 435                iommu_spec.args_count = count;
 436
 437                mtk_iommu_create_mapping(dev, &iommu_spec);
 438
 439                /* dev->iommu_fwspec might have changed */
 440                fwspec = dev_iommu_fwspec_get(dev);
 441
 442                of_node_put(iommu_spec.np);
 443        }
 444
 445        if (!fwspec || fwspec->ops != &mtk_iommu_ops)
 446                return ERR_PTR(-ENODEV); /* Not a iommu client device */
 447
 448        data = dev_iommu_priv_get(dev);
 449
 450        return &data->iommu;
 451}
 452
 453static void mtk_iommu_probe_finalize(struct device *dev)
 454{
 455        struct dma_iommu_mapping *mtk_mapping;
 456        struct mtk_iommu_data *data;
 457        int err;
 458
 459        data        = dev_iommu_priv_get(dev);
 460        mtk_mapping = data->mapping;
 461
 462        err = arm_iommu_attach_device(dev, mtk_mapping);
 463        if (err)
 464                dev_err(dev, "Can't create IOMMU mapping - DMA-OPS will not work\n");
 465}
 466
 467static void mtk_iommu_release_device(struct device *dev)
 468{
 469        struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
 470
 471        if (!fwspec || fwspec->ops != &mtk_iommu_ops)
 472                return;
 473
 474        iommu_fwspec_free(dev);
 475}
 476
 477static int mtk_iommu_hw_init(const struct mtk_iommu_data *data)
 478{
 479        u32 regval;
 480        int ret;
 481
 482        ret = clk_prepare_enable(data->bclk);
 483        if (ret) {
 484                dev_err(data->dev, "Failed to enable iommu bclk(%d)\n", ret);
 485                return ret;
 486        }
 487
 488        regval = F_MMU_CTRL_COHERENT_EN | F_MMU_TF_PROTECT_SEL(2);
 489        writel_relaxed(regval, data->base + REG_MMU_CTRL_REG);
 490
 491        regval = F_INT_TRANSLATION_FAULT |
 492                F_INT_MAIN_MULTI_HIT_FAULT |
 493                F_INT_INVALID_PA_FAULT |
 494                F_INT_ENTRY_REPLACEMENT_FAULT |
 495                F_INT_TABLE_WALK_FAULT |
 496                F_INT_TLB_MISS_FAULT |
 497                F_INT_PFH_DMA_FIFO_OVERFLOW |
 498                F_INT_MISS_DMA_FIFO_OVERFLOW;
 499        writel_relaxed(regval, data->base + REG_MMU_INT_CONTROL);
 500
 501        /* protect memory,hw will write here while translation fault */
 502        writel_relaxed(data->protect_base,
 503                        data->base + REG_MMU_IVRP_PADDR);
 504
 505        writel_relaxed(F_MMU_DCM_ON, data->base + REG_MMU_DCM);
 506
 507        if (devm_request_irq(data->dev, data->irq, mtk_iommu_isr, 0,
 508                             dev_name(data->dev), (void *)data)) {
 509                writel_relaxed(0, data->base + REG_MMU_PT_BASE_ADDR);
 510                clk_disable_unprepare(data->bclk);
 511                dev_err(data->dev, "Failed @ IRQ-%d Request\n", data->irq);
 512                return -ENODEV;
 513        }
 514
 515        return 0;
 516}
 517
 518static const struct iommu_ops mtk_iommu_ops = {
 519        .domain_alloc   = mtk_iommu_domain_alloc,
 520        .domain_free    = mtk_iommu_domain_free,
 521        .attach_dev     = mtk_iommu_attach_device,
 522        .detach_dev     = mtk_iommu_detach_device,
 523        .map            = mtk_iommu_map,
 524        .unmap          = mtk_iommu_unmap,
 525        .iova_to_phys   = mtk_iommu_iova_to_phys,
 526        .probe_device   = mtk_iommu_probe_device,
 527        .probe_finalize = mtk_iommu_probe_finalize,
 528        .release_device = mtk_iommu_release_device,
 529        .def_domain_type = mtk_iommu_def_domain_type,
 530        .device_group   = generic_device_group,
 531        .pgsize_bitmap  = ~0UL << MT2701_IOMMU_PAGE_SHIFT,
 532};
 533
 534static const struct of_device_id mtk_iommu_of_ids[] = {
 535        { .compatible = "mediatek,mt2701-m4u", },
 536        {}
 537};
 538
 539static const struct component_master_ops mtk_iommu_com_ops = {
 540        .bind           = mtk_iommu_bind,
 541        .unbind         = mtk_iommu_unbind,
 542};
 543
 544static int mtk_iommu_probe(struct platform_device *pdev)
 545{
 546        struct mtk_iommu_data           *data;
 547        struct device                   *dev = &pdev->dev;
 548        struct resource                 *res;
 549        struct component_match          *match = NULL;
 550        struct of_phandle_args          larb_spec;
 551        struct of_phandle_iterator      it;
 552        void                            *protect;
 553        int                             larb_nr, ret, err;
 554
 555        data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
 556        if (!data)
 557                return -ENOMEM;
 558
 559        data->dev = dev;
 560
 561        /* Protect memory. HW will access here while translation fault.*/
 562        protect = devm_kzalloc(dev, MTK_PROTECT_PA_ALIGN * 2,
 563                        GFP_KERNEL | GFP_DMA);
 564        if (!protect)
 565                return -ENOMEM;
 566        data->protect_base = ALIGN(virt_to_phys(protect), MTK_PROTECT_PA_ALIGN);
 567
 568        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 569        data->base = devm_ioremap_resource(dev, res);
 570        if (IS_ERR(data->base))
 571                return PTR_ERR(data->base);
 572
 573        data->irq = platform_get_irq(pdev, 0);
 574        if (data->irq < 0)
 575                return data->irq;
 576
 577        data->bclk = devm_clk_get(dev, "bclk");
 578        if (IS_ERR(data->bclk))
 579                return PTR_ERR(data->bclk);
 580
 581        larb_nr = 0;
 582        of_for_each_phandle(&it, err, dev->of_node,
 583                        "mediatek,larbs", NULL, 0) {
 584                struct platform_device *plarbdev;
 585                int count = of_phandle_iterator_args(&it, larb_spec.args,
 586                                        MAX_PHANDLE_ARGS);
 587
 588                if (count)
 589                        continue;
 590
 591                larb_spec.np = of_node_get(it.node);
 592                if (!of_device_is_available(larb_spec.np))
 593                        continue;
 594
 595                plarbdev = of_find_device_by_node(larb_spec.np);
 596                if (!plarbdev) {
 597                        plarbdev = of_platform_device_create(
 598                                                larb_spec.np, NULL,
 599                                                platform_bus_type.dev_root);
 600                        if (!plarbdev) {
 601                                of_node_put(larb_spec.np);
 602                                return -EPROBE_DEFER;
 603                        }
 604                }
 605
 606                data->larb_imu[larb_nr].dev = &plarbdev->dev;
 607                component_match_add_release(dev, &match, release_of,
 608                                            compare_of, larb_spec.np);
 609                larb_nr++;
 610        }
 611
 612        platform_set_drvdata(pdev, data);
 613
 614        ret = mtk_iommu_hw_init(data);
 615        if (ret)
 616                return ret;
 617
 618        ret = iommu_device_sysfs_add(&data->iommu, &pdev->dev, NULL,
 619                                     dev_name(&pdev->dev));
 620        if (ret)
 621                return ret;
 622
 623        iommu_device_set_ops(&data->iommu, &mtk_iommu_ops);
 624
 625        ret = iommu_device_register(&data->iommu);
 626        if (ret)
 627                return ret;
 628
 629        if (!iommu_present(&platform_bus_type))
 630                bus_set_iommu(&platform_bus_type,  &mtk_iommu_ops);
 631
 632        return component_master_add_with_match(dev, &mtk_iommu_com_ops, match);
 633}
 634
 635static int mtk_iommu_remove(struct platform_device *pdev)
 636{
 637        struct mtk_iommu_data *data = platform_get_drvdata(pdev);
 638
 639        iommu_device_sysfs_remove(&data->iommu);
 640        iommu_device_unregister(&data->iommu);
 641
 642        if (iommu_present(&platform_bus_type))
 643                bus_set_iommu(&platform_bus_type, NULL);
 644
 645        clk_disable_unprepare(data->bclk);
 646        devm_free_irq(&pdev->dev, data->irq, data);
 647        component_master_del(&pdev->dev, &mtk_iommu_com_ops);
 648        return 0;
 649}
 650
 651static int __maybe_unused mtk_iommu_suspend(struct device *dev)
 652{
 653        struct mtk_iommu_data *data = dev_get_drvdata(dev);
 654        struct mtk_iommu_suspend_reg *reg = &data->reg;
 655        void __iomem *base = data->base;
 656
 657        reg->standard_axi_mode = readl_relaxed(base +
 658                                               REG_MMU_STANDARD_AXI_MODE);
 659        reg->dcm_dis = readl_relaxed(base + REG_MMU_DCM);
 660        reg->ctrl_reg = readl_relaxed(base + REG_MMU_CTRL_REG);
 661        reg->int_control0 = readl_relaxed(base + REG_MMU_INT_CONTROL);
 662        return 0;
 663}
 664
 665static int __maybe_unused mtk_iommu_resume(struct device *dev)
 666{
 667        struct mtk_iommu_data *data = dev_get_drvdata(dev);
 668        struct mtk_iommu_suspend_reg *reg = &data->reg;
 669        void __iomem *base = data->base;
 670
 671        writel_relaxed(data->m4u_dom->pgt_pa, base + REG_MMU_PT_BASE_ADDR);
 672        writel_relaxed(reg->standard_axi_mode,
 673                       base + REG_MMU_STANDARD_AXI_MODE);
 674        writel_relaxed(reg->dcm_dis, base + REG_MMU_DCM);
 675        writel_relaxed(reg->ctrl_reg, base + REG_MMU_CTRL_REG);
 676        writel_relaxed(reg->int_control0, base + REG_MMU_INT_CONTROL);
 677        writel_relaxed(data->protect_base, base + REG_MMU_IVRP_PADDR);
 678        return 0;
 679}
 680
 681static const struct dev_pm_ops mtk_iommu_pm_ops = {
 682        SET_SYSTEM_SLEEP_PM_OPS(mtk_iommu_suspend, mtk_iommu_resume)
 683};
 684
 685static struct platform_driver mtk_iommu_driver = {
 686        .probe  = mtk_iommu_probe,
 687        .remove = mtk_iommu_remove,
 688        .driver = {
 689                .name = "mtk-iommu-v1",
 690                .of_match_table = mtk_iommu_of_ids,
 691                .pm = &mtk_iommu_pm_ops,
 692        }
 693};
 694
 695static int __init m4u_init(void)
 696{
 697        return platform_driver_register(&mtk_iommu_driver);
 698}
 699subsys_initcall(m4u_init);
 700