linux-sg2042/drivers/iommu/mtk_iommu.c

694 lines
19 KiB
C

/*
* 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/bootmem.h>
#include <linux/bug.h>
#include <linux/clk.h>
#include <linux/component.h>
#include <linux/device.h>
#include <linux/dma-iommu.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/iommu.h>
#include <linux/iopoll.h>
#include <linux/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 "mtk_iommu.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, ext) (((pa) >> 1) | ((!!(ext)) << 31))
#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_domain {
spinlock_t pgtlock; /* lock for page table */
struct io_pgtable_cfg cfg;
struct io_pgtable_ops *iop;
struct iommu_domain domain;
};
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);
data->tlb_flush_active = true;
}
static void mtk_iommu_tlb_sync(void *cookie)
{
struct mtk_iommu_data *data = cookie;
int ret;
u32 tmp;
/* Avoid timing out if there's nothing to wait for */
if (!data->tlb_flush_active)
return;
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);
data->tlb_flush_active = false;
}
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_smi_larb_iommu *larb_mmu;
unsigned int larbid, portid;
struct iommu_fwspec *fwspec = dev->iommu_fwspec;
int i;
for (i = 0; i < fwspec->num_ids; ++i) {
larbid = MTK_M4U_TO_LARB(fwspec->ids[i]);
portid = MTK_M4U_TO_PORT(fwspec->ids[i]);
larb_mmu = &data->smi_imu.larb_imu[larbid];
dev_dbg(dev, "%s iommu port: %d\n",
enable ? "enable" : "disable", portid);
if (enable)
larb_mmu->mmu |= MTK_SMI_MMU_EN(portid);
else
larb_mmu->mmu &= ~MTK_SMI_MMU_EN(portid);
}
}
static int mtk_iommu_domain_finalise(struct mtk_iommu_data *data)
{
struct mtk_iommu_domain *dom = data->m4u_dom;
spin_lock_init(&dom->pgtlock);
dom->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,
};
if (data->enable_4GB)
dom->cfg.quirks |= IO_PGTABLE_QUIRK_ARM_MTK_4GB;
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 */
dom->domain.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_data *data = dev->iommu_fwspec->iommu_priv;
int ret;
if (!data)
return -ENODEV;
if (!data->m4u_dom) {
data->m4u_dom = dom;
ret = mtk_iommu_domain_finalise(data);
if (ret) {
data->m4u_dom = NULL;
return ret;
}
} 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_data *data = dev->iommu_fwspec->iommu_priv;
if (!data)
return;
mtk_iommu_config(data, dev, false);
}
static int mtk_iommu_map(struct iommu_domain *domain, unsigned long iova,
phys_addr_t paddr, size_t size, int prot)
{
struct mtk_iommu_domain *dom = to_mtk_domain(domain);
unsigned 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 mtk_iommu_data *data;
struct iommu_group *group;
if (!dev->iommu_fwspec || dev->iommu_fwspec->ops != &mtk_iommu_ops)
return -ENODEV; /* Not a iommu client device */
data = dev->iommu_fwspec->iommu_priv;
iommu_device_link(&data->iommu, dev);
group = iommu_group_get_for_dev(dev);
if (IS_ERR(group))
return PTR_ERR(group);
iommu_group_put(group);
return 0;
}
static void mtk_iommu_remove_device(struct device *dev)
{
struct mtk_iommu_data *data;
if (!dev->iommu_fwspec || dev->iommu_fwspec->ops != &mtk_iommu_ops)
return;
data = dev->iommu_fwspec->iommu_priv;
iommu_device_unlink(&data->iommu, dev);
iommu_group_remove_device(dev);
iommu_fwspec_free(dev);
}
static struct iommu_group *mtk_iommu_device_group(struct device *dev)
{
struct mtk_iommu_data *data = dev->iommu_fwspec->iommu_priv;
if (!data)
return ERR_PTR(-ENODEV);
/* All the client devices are in the same m4u iommu-group */
if (!data->m4u_group) {
data->m4u_group = iommu_group_alloc();
if (IS_ERR(data->m4u_group))
dev_err(dev, "Failed to allocate M4U IOMMU group\n");
} else {
iommu_group_ref_get(data->m4u_group);
}
return data->m4u_group;
}
static int mtk_iommu_of_xlate(struct device *dev, struct of_phandle_args *args)
{
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->iommu_fwspec->iommu_priv) {
/* Get the m4u device */
m4updev = of_find_device_by_node(args->np);
if (WARN_ON(!m4updev))
return -EINVAL;
dev->iommu_fwspec->iommu_priv = platform_get_drvdata(m4updev);
}
return iommu_fwspec_add_ids(dev, args->args, 1);
}
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->enable_4GB),
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 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;
resource_size_t ioaddr;
struct component_match *match = NULL;
void *protect;
int i, larb_nr, 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);
/* Whether the current dram is over 4GB */
data->enable_4GB = !!(max_pfn > (0xffffffffUL >> PAGE_SHIFT));
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);
ioaddr = res->start;
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);
if (!plarbdev) {
plarbdev = of_platform_device_create(
larbnode, NULL,
platform_bus_type.dev_root);
if (!plarbdev) {
of_node_put(larbnode);
return -EPROBE_DEFER;
}
}
data->smi_imu.larb_imu[i].dev = &plarbdev->dev;
component_match_add_release(dev, &match, release_of,
compare_of, larbnode);
}
platform_set_drvdata(pdev, data);
ret = mtk_iommu_hw_init(data);
if (ret)
return ret;
ret = iommu_device_sysfs_add(&data->iommu, dev, NULL,
"mtk-iommu.%pa", &ioaddr);
if (ret)
return ret;
iommu_device_set_ops(&data->iommu, &mtk_iommu_ops);
iommu_device_set_fwnode(&data->iommu, &pdev->dev.of_node->fwnode);
ret = iommu_device_register(&data->iommu);
if (ret)
return ret;
if (!iommu_present(&platform_bus_type))
bus_set_iommu(&platform_bus_type, &mtk_iommu_ops);
return component_master_add_with_match(dev, &mtk_iommu_com_ops, match);
}
static int mtk_iommu_remove(struct platform_device *pdev)
{
struct mtk_iommu_data *data = platform_get_drvdata(pdev);
iommu_device_sysfs_remove(&data->iommu);
iommu_device_unregister(&data->iommu);
if (iommu_present(&platform_bus_type))
bus_set_iommu(&platform_bus_type, NULL);
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 __maybe_unused mtk_iommu_suspend(struct device *dev)
{
struct mtk_iommu_data *data = dev_get_drvdata(dev);
struct mtk_iommu_suspend_reg *reg = &data->reg;
void __iomem *base = data->base;
reg->standard_axi_mode = readl_relaxed(base +
REG_MMU_STANDARD_AXI_MODE);
reg->dcm_dis = readl_relaxed(base + REG_MMU_DCM_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 __maybe_unused mtk_iommu_resume(struct device *dev)
{
struct mtk_iommu_data *data = dev_get_drvdata(dev);
struct mtk_iommu_suspend_reg *reg = &data->reg;
void __iomem *base = data->base;
writel_relaxed(data->m4u_dom->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, data->enable_4GB),
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 (!pdev)
return -ENOMEM;
ret = platform_driver_register(&mtk_iommu_driver);
if (ret) {
pr_err("%s: Failed to register driver\n", __func__);
return ret;
}
return 0;
}
IOMMU_OF_DECLARE(mtkm4u, "mediatek,mt8173-m4u", mtk_iommu_init_fn);