drivers/iommu/mtk_iommu.c - kernel/msm-4.9 - Gitiles

 /*
  * Copyright (c) 2015-2016 MediaTek Inc.
  * Author: Yong Wu <yong.wu@mediatek.com>
  *
  * 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/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/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 <dt-bindings/memory/mt8173-larb-port.h>
 #include <soc/mediatek/smi.h>

 #include "io-pgtable.h"

 #define REG_MMU_PT_BASE_ADDR			0x000

 #define REG_MMU_INVALIDATE			0x020
 #define F_ALL_INVLD				0x2
 #define F_MMU_INV_RANGE				0x1

 #define REG_MMU_INVLD_START_A			0x024
 #define REG_MMU_INVLD_END_A			0x028

 #define REG_MMU_INV_SEL				0x038
 #define F_INVLD_EN0				BIT(0)
 #define F_INVLD_EN1				BIT(1)

 #define REG_MMU_STANDARD_AXI_MODE		0x048
 #define REG_MMU_DCM_DIS				0x050

 #define REG_MMU_CTRL_REG			0x110
 #define F_MMU_PREFETCH_RT_REPLACE_MOD		BIT(4)
 #define F_MMU_TF_PROTECT_SEL(prot)		(((prot) & 0x3) << 5)

 #define REG_MMU_IVRP_PADDR			0x114
 #define F_MMU_IVRP_PA_SET(pa)			((pa) >> 1)

 #define REG_MMU_INT_CONTROL0			0x120
 #define F_L2_MULIT_HIT_EN			BIT(0)
 #define F_TABLE_WALK_FAULT_INT_EN		BIT(1)
 #define F_PREETCH_FIFO_OVERFLOW_INT_EN		BIT(2)
 #define F_MISS_FIFO_OVERFLOW_INT_EN		BIT(3)
 #define F_PREFETCH_FIFO_ERR_INT_EN		BIT(5)
 #define F_MISS_FIFO_ERR_INT_EN			BIT(6)
 #define F_INT_CLR_BIT				BIT(12)

 #define REG_MMU_INT_MAIN_CONTROL		0x124
 #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_TLB_MISS_FAULT			BIT(4)
 #define F_INT_MISS_TRANSACTION_FIFO_FAULT	BIT(5)
 #define F_INT_PRETETCH_TRANSATION_FIFO_FAULT	BIT(6)

 #define REG_MMU_CPE_DONE			0x12C

 #define REG_MMU_FAULT_ST1			0x134

 #define REG_MMU_FAULT_VA			0x13c
 #define F_MMU_FAULT_VA_MSK			0xfffff000
 #define F_MMU_FAULT_VA_WRITE_BIT		BIT(1)
 #define F_MMU_FAULT_VA_LAYER_BIT		BIT(0)

 #define REG_MMU_INVLD_PA			0x140
 #define REG_MMU_INT_ID				0x150
 #define F_MMU0_INT_ID_LARB_ID(a)		(((a) >> 7) & 0x7)
 #define F_MMU0_INT_ID_PORT_ID(a)		(((a) >> 2) & 0x1f)

 #define MTK_PROTECT_PA_ALIGN			128

 struct mtk_iommu_suspend_reg {
 	u32				standard_axi_mode;
 	u32				dcm_dis;
 	u32				ctrl_reg;
 	u32				int_control0;
 	u32				int_main_control;
 };

 struct mtk_iommu_client_priv {
 	struct list_head		client;
 	unsigned int			mtk_m4u_id;
 	struct device			*m4udev;
 };

 struct mtk_iommu_domain {
 	spinlock_t			pgtlock; /* lock for page table */

 	struct io_pgtable_cfg		cfg;
 	struct io_pgtable_ops		*iop;

 	struct iommu_domain		domain;
 };

 struct mtk_iommu_data {
 	void __iomem			*base;
 	int				irq;
 	struct device			*dev;
 	struct clk			*bclk;
 	phys_addr_t			protect_base; /* protect memory base */
 	struct mtk_iommu_suspend_reg	reg;
 	struct mtk_iommu_domain		*m4u_dom;
 	struct iommu_group		*m4u_group;
 	struct mtk_smi_iommu		smi_imu;      /* SMI larb iommu info */
 };

 static struct iommu_ops mtk_iommu_ops;

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

 static void mtk_iommu_tlb_flush_all(void *cookie)
 {
 	struct mtk_iommu_data *data = cookie;

 	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_add_flush_nosync(unsigned long iova, size_t size,
 					   size_t granule, bool leaf,
 					   void *cookie)
 {
 	struct mtk_iommu_data *data = cookie;

 	writel_relaxed(F_INVLD_EN1 | F_INVLD_EN0, data->base + REG_MMU_INV_SEL);

 	writel_relaxed(iova, data->base + REG_MMU_INVLD_START_A);
 	writel_relaxed(iova + size - 1, data->base + REG_MMU_INVLD_END_A);
 	writel_relaxed(F_MMU_INV_RANGE, data->base + REG_MMU_INVALIDATE);
 }

 static void mtk_iommu_tlb_sync(void *cookie)
 {
 	struct mtk_iommu_data *data = cookie;
 	int ret;
 	u32 tmp;

 	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(cookie);
 	}
 	/* Clear the CPE status */
 	writel_relaxed(0, data->base + REG_MMU_CPE_DONE);
 }

 static const struct iommu_gather_ops mtk_iommu_gather_ops = {
 	.tlb_flush_all = mtk_iommu_tlb_flush_all,
 	.tlb_add_flush = mtk_iommu_tlb_add_flush_nosync,
 	.tlb_sync = mtk_iommu_tlb_sync,
 };

 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;
 	bool layer, write;

 	/* Read error info from registers */
 	int_state = readl_relaxed(data->base + REG_MMU_FAULT_ST1);
 	fault_iova = readl_relaxed(data->base + REG_MMU_FAULT_VA);
 	layer = fault_iova & F_MMU_FAULT_VA_LAYER_BIT;
 	write = fault_iova & F_MMU_FAULT_VA_WRITE_BIT;
 	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 = F_MMU0_INT_ID_LARB_ID(regval);
 	fault_port = F_MMU0_INT_ID_PORT_ID(regval);

 	if (report_iommu_fault(&dom->domain, data->dev, fault_iova,
 			       write ? IOMMU_FAULT_WRITE : IOMMU_FAULT_READ)) {
 		dev_err_ratelimited(
 			data->dev,
 			"fault type=0x%x iova=0x%x pa=0x%x larb=%d port=%d layer=%d %s\n",
 			int_state, fault_iova, fault_pa, fault_larb, fault_port,
 			layer, write ? "write" : "read");
 	}

 	/* Interrupt clear */
 	regval = readl_relaxed(data->base + REG_MMU_INT_CONTROL0);
 	regval |= F_INT_CLR_BIT;
 	writel_relaxed(regval, data->base + REG_MMU_INT_CONTROL0);

 	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_iommu_client_priv *head, *cur, *next;
 	struct mtk_smi_larb_iommu    *larb_mmu;
 	unsigned int                 larbid, portid;

 	head = dev->archdata.iommu;
 	list_for_each_entry_safe(cur, next, &head->client, client) {
 		larbid = MTK_M4U_TO_LARB(cur->mtk_m4u_id);
 		portid = MTK_M4U_TO_PORT(cur->mtk_m4u_id);
 		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->cfg = (struct io_pgtable_cfg) {
 		.quirks = IO_PGTABLE_QUIRK_ARM_NS |
 			IO_PGTABLE_QUIRK_NO_PERMS |
 			IO_PGTABLE_QUIRK_TLBI_ON_MAP,
 		.pgsize_bitmap = mtk_iommu_ops.pgsize_bitmap,
 		.ias = 32,
 		.oas = 32,
 		.tlb = &mtk_iommu_gather_ops,
 		.iommu_dev = data->dev,
 	};

 	dom->iop = alloc_io_pgtable_ops(ARM_V7S, &dom->cfg, data);
 	if (!dom->iop) {
 		dev_err(data->dev, "Failed to alloc io pgtable\n");
 		return -EINVAL;
 	}

 	/* Update our support page sizes bitmap */
 	mtk_iommu_ops.pgsize_bitmap = dom->cfg.pgsize_bitmap;

 	writel(data->m4u_dom->cfg.arm_v7s_cfg.ttbr[0],
 	       data->base + REG_MMU_PT_BASE_ADDR);
 	return 0;
 }

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

 	if (type != IOMMU_DOMAIN_DMA)
 		return NULL;

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

 	if (iommu_get_dma_cookie(&dom->domain)) {
 		kfree(dom);
 		return NULL;
 	}

 	dom->domain.geometry.aperture_start = 0;
 	dom->domain.geometry.aperture_end = DMA_BIT_MASK(32);
 	dom->domain.geometry.force_aperture = true;

 	return &dom->domain;
 }

 static void mtk_iommu_domain_free(struct iommu_domain *domain)
 {
 	iommu_put_dma_cookie(domain);
 	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_client_priv *priv = dev->archdata.iommu;
 	struct mtk_iommu_data *data;
 	int ret;

 	if (!priv)
 		return -ENODEV;

 	data = dev_get_drvdata(priv->m4udev);
 	if (!data->m4u_dom) {
 		data->m4u_dom = dom;
 		ret = mtk_iommu_domain_finalise(data);
 		if (ret) {
 			data->m4u_dom = NULL;
 			return ret;
 		}
 	} else if (data->m4u_dom != dom) {
 		/* All the client devices should be in the same m4u domain */
 		dev_err(dev, "try to attach into the error iommu domain\n");
 		return -EPERM;
 	}

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

 static void mtk_iommu_detach_device(struct iommu_domain *domain,
 				    struct device *dev)
 {
 	struct mtk_iommu_client_priv *priv = dev->archdata.iommu;
 	struct mtk_iommu_data *data;

 	if (!priv)
 		return;

 	data = dev_get_drvdata(priv->m4udev);
 	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 long flags;
 	int ret;

 	spin_lock_irqsave(&dom->pgtlock, flags);
 	ret = dom->iop->map(dom->iop, iova, paddr, size, prot);
 	spin_unlock_irqrestore(&dom->pgtlock, flags);

 	return ret;
 }

 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;
 	size_t unmapsz;

 	spin_lock_irqsave(&dom->pgtlock, flags);
 	unmapsz = dom->iop->unmap(dom->iop, iova, size);
 	spin_unlock_irqrestore(&dom->pgtlock, flags);

 	return unmapsz;
 }

 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->iop->iova_to_phys(dom->iop, iova);
 	spin_unlock_irqrestore(&dom->pgtlock, flags);

 	return pa;
 }

 static int mtk_iommu_add_device(struct device *dev)
 {
 	struct iommu_group *group;

 	if (!dev->archdata.iommu) /* Not a iommu client device */
 		return -ENODEV;

 	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_client_priv *head, *cur, *next;

 	head = dev->archdata.iommu;
 	if (!head)
 		return;

 	list_for_each_entry_safe(cur, next, &head->client, client) {
 		list_del(&cur->client);
 		kfree(cur);
 	}
 	kfree(head);
 	dev->archdata.iommu = NULL;

 	iommu_group_remove_device(dev);
 }

 static struct iommu_group *mtk_iommu_device_group(struct device *dev)
 {
 	struct mtk_iommu_data *data;
 	struct mtk_iommu_client_priv *priv;

 	priv = dev->archdata.iommu;
 	if (!priv)
 		return ERR_PTR(-ENODEV);

 	/* All the client devices are in the same m4u iommu-group */
 	data = dev_get_drvdata(priv->m4udev);
 	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");
 	}
 	return data->m4u_group;
 }

 static int mtk_iommu_of_xlate(struct device *dev, struct of_phandle_args *args)
 {
 	struct mtk_iommu_client_priv *head, *priv, *next;
 	struct platform_device *m4updev;

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

 	if (!dev->archdata.iommu) {
 		/* Get the m4u device */
 		m4updev = of_find_device_by_node(args->np);
 		of_node_put(args->np);
 		if (WARN_ON(!m4updev))
 			return -EINVAL;

 		head = kzalloc(sizeof(*head), GFP_KERNEL);
 		if (!head)
 			return -ENOMEM;

 		dev->archdata.iommu = head;
 		INIT_LIST_HEAD(&head->client);
 		head->m4udev = &m4updev->dev;
 	} else {
 		head = dev->archdata.iommu;
 	}

 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 	if (!priv)
 		goto err_free_mem;

 	priv->mtk_m4u_id = args->args[0];
 	list_add_tail(&priv->client, &head->client);

 	return 0;

 err_free_mem:
 	list_for_each_entry_safe(priv, next, &head->client, client)
 		kfree(priv);
 	kfree(head);
 	dev->archdata.iommu = NULL;
 	return -ENOMEM;
 }

 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,
 	.of_xlate	= mtk_iommu_of_xlate,
 	.pgsize_bitmap	= SZ_4K | SZ_64K | SZ_1M | SZ_16M,
 };

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

 	regval = F_L2_MULIT_HIT_EN |
 		F_TABLE_WALK_FAULT_INT_EN |
 		F_PREETCH_FIFO_OVERFLOW_INT_EN |
 		F_MISS_FIFO_OVERFLOW_INT_EN |
 		F_PREFETCH_FIFO_ERR_INT_EN |
 		F_MISS_FIFO_ERR_INT_EN;
 	writel_relaxed(regval, data->base + REG_MMU_INT_CONTROL0);

 	regval = F_INT_TRANSLATION_FAULT |
 		F_INT_MAIN_MULTI_HIT_FAULT |
 		F_INT_INVALID_PA_FAULT |
 		F_INT_ENTRY_REPLACEMENT_FAULT |
 		F_INT_TLB_MISS_FAULT |
 		F_INT_MISS_TRANSACTION_FIFO_FAULT |
 		F_INT_PRETETCH_TRANSATION_FIFO_FAULT;
 	writel_relaxed(regval, data->base + REG_MMU_INT_MAIN_CONTROL);

 	writel_relaxed(F_MMU_IVRP_PA_SET(data->protect_base),
 		       data->base + REG_MMU_IVRP_PADDR);

 	writel_relaxed(0, data->base + REG_MMU_DCM_DIS);
 	writel_relaxed(0, data->base + REG_MMU_STANDARD_AXI_MODE);

 	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 int compare_of(struct device *dev, void *data)
 {
 	return dev->of_node == data;
 }

 static int mtk_iommu_bind(struct device *dev)
 {
 	struct mtk_iommu_data *data = dev_get_drvdata(dev);

 	return component_bind_all(dev, &data->smi_imu);
 }

 static void mtk_iommu_unbind(struct device *dev)
 {
 	struct mtk_iommu_data *data = dev_get_drvdata(dev);

 	component_unbind_all(dev, &data->smi_imu);
 }

 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;
 	void                    *protect;
 	unsigned int            i, larb_nr;
 	int                     ret;

 	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);
 	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 = of_count_phandle_with_args(dev->of_node,
 					     "mediatek,larbs", NULL);
 	if (larb_nr < 0)
 		return larb_nr;
 	data->smi_imu.larb_nr = larb_nr;

 	for (i = 0; i < larb_nr; i++) {
 		struct device_node *larbnode;
 		struct platform_device *plarbdev;

 		larbnode = of_parse_phandle(dev->of_node, "mediatek,larbs", i);
 		if (!larbnode)
 			return -EINVAL;

 		if (!of_device_is_available(larbnode))
 			continue;

 		plarbdev = of_find_device_by_node(larbnode);
 		of_node_put(larbnode);
 		if (!plarbdev) {
 			plarbdev = of_platform_device_create(
 						larbnode, NULL,
 						platform_bus_type.dev_root);
 			if (IS_ERR(plarbdev))
 				return -EPROBE_DEFER;
 		}
 		data->smi_imu.larb_imu[i].dev = &plarbdev->dev;

 		component_match_add(dev, &match, compare_of, larbnode);
 	}

 	platform_set_drvdata(pdev, data);

 	ret = mtk_iommu_hw_init(data);
 	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);

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

 	free_io_pgtable_ops(data->m4u_dom->iop);
 	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 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_DIS);
 	reg->ctrl_reg = readl_relaxed(base + REG_MMU_CTRL_REG);
 	reg->int_control0 = readl_relaxed(base + REG_MMU_INT_CONTROL0);
 	reg->int_main_control = readl_relaxed(base + REG_MMU_INT_MAIN_CONTROL);
 	return 0;
 }

 static int 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->cfg.arm_v7s_cfg.ttbr[0],
 		       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_DIS);
 	writel_relaxed(reg->ctrl_reg, base + REG_MMU_CTRL_REG);
 	writel_relaxed(reg->int_control0, base + REG_MMU_INT_CONTROL0);
 	writel_relaxed(reg->int_main_control, base + REG_MMU_INT_MAIN_CONTROL);
 	writel_relaxed(F_MMU_IVRP_PA_SET(data->protect_base),
 		       base + REG_MMU_IVRP_PADDR);
 	return 0;
 }

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

 static const struct of_device_id mtk_iommu_of_ids[] = {
 	{ .compatible = "mediatek,mt8173-m4u", },
 	{}
 };

 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 mtk_iommu_init_fn(struct device_node *np)
 {
 	int ret;
 	struct platform_device *pdev;

 	pdev = of_platform_device_create(np, NULL, platform_bus_type.dev_root);
 	if (IS_ERR(pdev))
 		return PTR_ERR(pdev);

 	ret = platform_driver_register(&mtk_iommu_driver);
 	if (ret) {
 		pr_err("%s: Failed to register driver\n", __func__);
 		return ret;
 	}

 	of_iommu_set_ops(np, &mtk_iommu_ops);
 	return 0;
 }

 IOMMU_OF_DECLARE(mtkm4u, "mediatek,mt8173-m4u", mtk_iommu_init_fn);
	/*
	* Copyright (c) 2015-2016 MediaTek Inc.
	* Author: Yong Wu <yong.wu@mediatek.com>
	*
	* 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/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/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 <dt-bindings/memory/mt8173-larb-port.h>
	#include <soc/mediatek/smi.h>

	#include "io-pgtable.h"

	#define REG_MMU_PT_BASE_ADDR 0x000

	#define REG_MMU_INVALIDATE 0x020
	#define F_ALL_INVLD 0x2
	#define F_MMU_INV_RANGE 0x1

	#define REG_MMU_INVLD_START_A 0x024
	#define REG_MMU_INVLD_END_A 0x028

	#define REG_MMU_INV_SEL 0x038
	#define F_INVLD_EN0 BIT(0)
	#define F_INVLD_EN1 BIT(1)

	#define REG_MMU_STANDARD_AXI_MODE 0x048
	#define REG_MMU_DCM_DIS 0x050

	#define REG_MMU_CTRL_REG 0x110
	#define F_MMU_PREFETCH_RT_REPLACE_MOD BIT(4)
	#define F_MMU_TF_PROTECT_SEL(prot) (((prot) & 0x3) << 5)

	#define REG_MMU_IVRP_PADDR 0x114
	#define F_MMU_IVRP_PA_SET(pa) ((pa) >> 1)

	#define REG_MMU_INT_CONTROL0 0x120
	#define F_L2_MULIT_HIT_EN BIT(0)
	#define F_TABLE_WALK_FAULT_INT_EN BIT(1)
	#define F_PREETCH_FIFO_OVERFLOW_INT_EN BIT(2)
	#define F_MISS_FIFO_OVERFLOW_INT_EN BIT(3)
	#define F_PREFETCH_FIFO_ERR_INT_EN BIT(5)
	#define F_MISS_FIFO_ERR_INT_EN BIT(6)
	#define F_INT_CLR_BIT BIT(12)

	#define REG_MMU_INT_MAIN_CONTROL 0x124
	#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_TLB_MISS_FAULT BIT(4)
	#define F_INT_MISS_TRANSACTION_FIFO_FAULT BIT(5)
	#define F_INT_PRETETCH_TRANSATION_FIFO_FAULT BIT(6)

	#define REG_MMU_CPE_DONE 0x12C

	#define REG_MMU_FAULT_ST1 0x134

	#define REG_MMU_FAULT_VA 0x13c
	#define F_MMU_FAULT_VA_MSK 0xfffff000
	#define F_MMU_FAULT_VA_WRITE_BIT BIT(1)
	#define F_MMU_FAULT_VA_LAYER_BIT BIT(0)

	#define REG_MMU_INVLD_PA 0x140
	#define REG_MMU_INT_ID 0x150
	#define F_MMU0_INT_ID_LARB_ID(a) (((a) >> 7) & 0x7)
	#define F_MMU0_INT_ID_PORT_ID(a) (((a) >> 2) & 0x1f)

	#define MTK_PROTECT_PA_ALIGN 128

	struct mtk_iommu_suspend_reg {
	u32 standard_axi_mode;
	u32 dcm_dis;
	u32 ctrl_reg;
	u32 int_control0;
	u32 int_main_control;
	};

	struct mtk_iommu_client_priv {
	struct list_head client;
	unsigned int mtk_m4u_id;
	struct device *m4udev;
	};

	struct mtk_iommu_domain {
	spinlock_t pgtlock; /* lock for page table */

	struct io_pgtable_cfg cfg;
	struct io_pgtable_ops *iop;

	struct iommu_domain domain;
	};

	struct mtk_iommu_data {
	void __iomem *base;
	int irq;
	struct device *dev;
	struct clk *bclk;
	phys_addr_t protect_base; /* protect memory base */
	struct mtk_iommu_suspend_reg reg;
	struct mtk_iommu_domain *m4u_dom;
	struct iommu_group *m4u_group;
	struct mtk_smi_iommu smi_imu; /* SMI larb iommu info */
	};

	static struct iommu_ops mtk_iommu_ops;

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

	static void mtk_iommu_tlb_flush_all(void *cookie)
	{
	struct mtk_iommu_data *data = cookie;

	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_add_flush_nosync(unsigned long iova, size_t size,
	size_t granule, bool leaf,
	void *cookie)
	{
	struct mtk_iommu_data *data = cookie;

	writel_relaxed(F_INVLD_EN1 \| F_INVLD_EN0, data->base + REG_MMU_INV_SEL);

	writel_relaxed(iova, data->base + REG_MMU_INVLD_START_A);
	writel_relaxed(iova + size - 1, data->base + REG_MMU_INVLD_END_A);
	writel_relaxed(F_MMU_INV_RANGE, data->base + REG_MMU_INVALIDATE);
	}

	static void mtk_iommu_tlb_sync(void *cookie)
	{
	struct mtk_iommu_data *data = cookie;
	int ret;
	u32 tmp;

	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(cookie);
	}
	/* Clear the CPE status */
	writel_relaxed(0, data->base + REG_MMU_CPE_DONE);
	}

	static const struct iommu_gather_ops mtk_iommu_gather_ops = {
	.tlb_flush_all = mtk_iommu_tlb_flush_all,
	.tlb_add_flush = mtk_iommu_tlb_add_flush_nosync,
	.tlb_sync = mtk_iommu_tlb_sync,
	};

	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;
	bool layer, write;

	/* Read error info from registers */
	int_state = readl_relaxed(data->base + REG_MMU_FAULT_ST1);
	fault_iova = readl_relaxed(data->base + REG_MMU_FAULT_VA);
	layer = fault_iova & F_MMU_FAULT_VA_LAYER_BIT;
	write = fault_iova & F_MMU_FAULT_VA_WRITE_BIT;
	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 = F_MMU0_INT_ID_LARB_ID(regval);
	fault_port = F_MMU0_INT_ID_PORT_ID(regval);

	if (report_iommu_fault(&dom->domain, data->dev, fault_iova,
	write ? IOMMU_FAULT_WRITE : IOMMU_FAULT_READ)) {
	dev_err_ratelimited(
	data->dev,
	"fault type=0x%x iova=0x%x pa=0x%x larb=%d port=%d layer=%d %s\n",
	int_state, fault_iova, fault_pa, fault_larb, fault_port,
	layer, write ? "write" : "read");
	}

	/* Interrupt clear */
	regval = readl_relaxed(data->base + REG_MMU_INT_CONTROL0);
	regval \|= F_INT_CLR_BIT;
	writel_relaxed(regval, data->base + REG_MMU_INT_CONTROL0);

	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_iommu_client_priv head, cur, *next;
	struct mtk_smi_larb_iommu *larb_mmu;
	unsigned int larbid, portid;

	head = dev->archdata.iommu;
	list_for_each_entry_safe(cur, next, &head->client, client) {
	larbid = MTK_M4U_TO_LARB(cur->mtk_m4u_id);
	portid = MTK_M4U_TO_PORT(cur->mtk_m4u_id);
	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->cfg = (struct io_pgtable_cfg) {
	.quirks = IO_PGTABLE_QUIRK_ARM_NS \|
	IO_PGTABLE_QUIRK_NO_PERMS \|
	IO_PGTABLE_QUIRK_TLBI_ON_MAP,
	.pgsize_bitmap = mtk_iommu_ops.pgsize_bitmap,
	.ias = 32,
	.oas = 32,
	.tlb = &mtk_iommu_gather_ops,
	.iommu_dev = data->dev,
	};

	dom->iop = alloc_io_pgtable_ops(ARM_V7S, &dom->cfg, data);
	if (!dom->iop) {
	dev_err(data->dev, "Failed to alloc io pgtable\n");
	return -EINVAL;
	}

	/* Update our support page sizes bitmap */
	mtk_iommu_ops.pgsize_bitmap = dom->cfg.pgsize_bitmap;

	writel(data->m4u_dom->cfg.arm_v7s_cfg.ttbr[0],
	data->base + REG_MMU_PT_BASE_ADDR);
	return 0;
	}

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

	if (type != IOMMU_DOMAIN_DMA)
	return NULL;

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

	if (iommu_get_dma_cookie(&dom->domain)) {
	kfree(dom);
	return NULL;
	}

	dom->domain.geometry.aperture_start = 0;
	dom->domain.geometry.aperture_end = DMA_BIT_MASK(32);
	dom->domain.geometry.force_aperture = true;

	return &dom->domain;
	}

	static void mtk_iommu_domain_free(struct iommu_domain *domain)
	{
	iommu_put_dma_cookie(domain);
	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_client_priv *priv = dev->archdata.iommu;
	struct mtk_iommu_data *data;
	int ret;

	if (!priv)
	return -ENODEV;

	data = dev_get_drvdata(priv->m4udev);
	if (!data->m4u_dom) {
	data->m4u_dom = dom;
	ret = mtk_iommu_domain_finalise(data);
	if (ret) {
	data->m4u_dom = NULL;
	return ret;
	}
	} else if (data->m4u_dom != dom) {
	/* All the client devices should be in the same m4u domain */
	dev_err(dev, "try to attach into the error iommu domain\n");
	return -EPERM;
	}

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

	static void mtk_iommu_detach_device(struct iommu_domain *domain,
	struct device *dev)
	{
	struct mtk_iommu_client_priv *priv = dev->archdata.iommu;
	struct mtk_iommu_data *data;

	if (!priv)
	return;

	data = dev_get_drvdata(priv->m4udev);
	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 long flags;
	int ret;

	spin_lock_irqsave(&dom->pgtlock, flags);
	ret = dom->iop->map(dom->iop, iova, paddr, size, prot);
	spin_unlock_irqrestore(&dom->pgtlock, flags);

	return ret;
	}

	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;
	size_t unmapsz;

	spin_lock_irqsave(&dom->pgtlock, flags);
	unmapsz = dom->iop->unmap(dom->iop, iova, size);
	spin_unlock_irqrestore(&dom->pgtlock, flags);

	return unmapsz;
	}

	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->iop->iova_to_phys(dom->iop, iova);
	spin_unlock_irqrestore(&dom->pgtlock, flags);

	return pa;
	}

	static int mtk_iommu_add_device(struct device *dev)
	{
	struct iommu_group *group;

	if (!dev->archdata.iommu) /* Not a iommu client device */
	return -ENODEV;

	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_client_priv head, cur, *next;

	head = dev->archdata.iommu;
	if (!head)
	return;

	list_for_each_entry_safe(cur, next, &head->client, client) {
	list_del(&cur->client);
	kfree(cur);
	}
	kfree(head);
	dev->archdata.iommu = NULL;

	iommu_group_remove_device(dev);
	}

	static struct iommu_group mtk_iommu_device_group(struct device dev)
	{
	struct mtk_iommu_data *data;
	struct mtk_iommu_client_priv *priv;

	priv = dev->archdata.iommu;
	if (!priv)
	return ERR_PTR(-ENODEV);

	/* All the client devices are in the same m4u iommu-group */
	data = dev_get_drvdata(priv->m4udev);
	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");
	}
	return data->m4u_group;
	}

	static int mtk_iommu_of_xlate(struct device dev, struct of_phandle_args args)
	{
	struct mtk_iommu_client_priv head, priv, *next;
	struct platform_device *m4updev;

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

	if (!dev->archdata.iommu) {
	/* Get the m4u device */
	m4updev = of_find_device_by_node(args->np);
	of_node_put(args->np);
	if (WARN_ON(!m4updev))
	return -EINVAL;

	head = kzalloc(sizeof(*head), GFP_KERNEL);
	if (!head)
	return -ENOMEM;

	dev->archdata.iommu = head;
	INIT_LIST_HEAD(&head->client);
	head->m4udev = &m4updev->dev;
	} else {
	head = dev->archdata.iommu;
	}

	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
	if (!priv)
	goto err_free_mem;

	priv->mtk_m4u_id = args->args[0];
	list_add_tail(&priv->client, &head->client);

	return 0;

	err_free_mem:
	list_for_each_entry_safe(priv, next, &head->client, client)
	kfree(priv);
	kfree(head);
	dev->archdata.iommu = NULL;
	return -ENOMEM;
	}

	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,
	.of_xlate = mtk_iommu_of_xlate,
	.pgsize_bitmap = SZ_4K \| SZ_64K \| SZ_1M \| SZ_16M,
	};

	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_PREFETCH_RT_REPLACE_MOD \|
	F_MMU_TF_PROTECT_SEL(2);
	writel_relaxed(regval, data->base + REG_MMU_CTRL_REG);

	regval = F_L2_MULIT_HIT_EN \|
	F_TABLE_WALK_FAULT_INT_EN \|
	F_PREETCH_FIFO_OVERFLOW_INT_EN \|
	F_MISS_FIFO_OVERFLOW_INT_EN \|
	F_PREFETCH_FIFO_ERR_INT_EN \|
	F_MISS_FIFO_ERR_INT_EN;
	writel_relaxed(regval, data->base + REG_MMU_INT_CONTROL0);

	regval = F_INT_TRANSLATION_FAULT \|
	F_INT_MAIN_MULTI_HIT_FAULT \|
	F_INT_INVALID_PA_FAULT \|
	F_INT_ENTRY_REPLACEMENT_FAULT \|
	F_INT_TLB_MISS_FAULT \|
	F_INT_MISS_TRANSACTION_FIFO_FAULT \|
	F_INT_PRETETCH_TRANSATION_FIFO_FAULT;
	writel_relaxed(regval, data->base + REG_MMU_INT_MAIN_CONTROL);

	writel_relaxed(F_MMU_IVRP_PA_SET(data->protect_base),
	data->base + REG_MMU_IVRP_PADDR);

	writel_relaxed(0, data->base + REG_MMU_DCM_DIS);
	writel_relaxed(0, data->base + REG_MMU_STANDARD_AXI_MODE);

	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 int compare_of(struct device dev, void data)
	{
	return dev->of_node == data;
	}

	static int mtk_iommu_bind(struct device *dev)
	{
	struct mtk_iommu_data *data = dev_get_drvdata(dev);

	return component_bind_all(dev, &data->smi_imu);
	}

	static void mtk_iommu_unbind(struct device *dev)
	{
	struct mtk_iommu_data *data = dev_get_drvdata(dev);

	component_unbind_all(dev, &data->smi_imu);
	}

	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;
	void *protect;
	unsigned int i, larb_nr;
	int ret;

	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);
	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 = of_count_phandle_with_args(dev->of_node,
	"mediatek,larbs", NULL);
	if (larb_nr < 0)
	return larb_nr;
	data->smi_imu.larb_nr = larb_nr;

	for (i = 0; i < larb_nr; i++) {
	struct device_node *larbnode;
	struct platform_device *plarbdev;

	larbnode = of_parse_phandle(dev->of_node, "mediatek,larbs", i);
	if (!larbnode)
	return -EINVAL;

	if (!of_device_is_available(larbnode))
	continue;

	plarbdev = of_find_device_by_node(larbnode);
	of_node_put(larbnode);
	if (!plarbdev) {
	plarbdev = of_platform_device_create(
	larbnode, NULL,
	platform_bus_type.dev_root);
	if (IS_ERR(plarbdev))
	return -EPROBE_DEFER;
	}
	data->smi_imu.larb_imu[i].dev = &plarbdev->dev;

	component_match_add(dev, &match, compare_of, larbnode);
	}

	platform_set_drvdata(pdev, data);

	ret = mtk_iommu_hw_init(data);
	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);

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

	free_io_pgtable_ops(data->m4u_dom->iop);
	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 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_DIS);
	reg->ctrl_reg = readl_relaxed(base + REG_MMU_CTRL_REG);
	reg->int_control0 = readl_relaxed(base + REG_MMU_INT_CONTROL0);
	reg->int_main_control = readl_relaxed(base + REG_MMU_INT_MAIN_CONTROL);
	return 0;
	}

	static int 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->cfg.arm_v7s_cfg.ttbr[0],
	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_DIS);
	writel_relaxed(reg->ctrl_reg, base + REG_MMU_CTRL_REG);
	writel_relaxed(reg->int_control0, base + REG_MMU_INT_CONTROL0);
	writel_relaxed(reg->int_main_control, base + REG_MMU_INT_MAIN_CONTROL);
	writel_relaxed(F_MMU_IVRP_PA_SET(data->protect_base),
	base + REG_MMU_IVRP_PADDR);
	return 0;
	}

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

	static const struct of_device_id mtk_iommu_of_ids[] = {
	{ .compatible = "mediatek,mt8173-m4u", },
	{}
	};

	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 mtk_iommu_init_fn(struct device_node *np)
	{
	int ret;
	struct platform_device *pdev;

	pdev = of_platform_device_create(np, NULL, platform_bus_type.dev_root);
	if (IS_ERR(pdev))
	return PTR_ERR(pdev);

	ret = platform_driver_register(&mtk_iommu_driver);
	if (ret) {
	pr_err("%s: Failed to register driver\n", __func__);
	return ret;
	}

	of_iommu_set_ops(np, &mtk_iommu_ops);
	return 0;
	}

	IOMMU_OF_DECLARE(mtkm4u, "mediatek,mt8173-m4u", mtk_iommu_init_fn);