// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2011,2016 Samsung Electronics Co., Ltd.
* http://www.samsung.com
*/
#ifdef [31mCONFIG_EXYNOS_IOMMU_DEBUG[0m
#define DEBUG
#endif
#include <linux/clk.h>
#include <linux/dma-mapping.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/iommu.h>
#include <linux/interrupt.h>
#include <linux/kmemleak.h>
#include <linux/list.h>
#include <linux/of.h>
#include <linux/of_iommu.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/slab.h>
#include <linux/dma-iommu.h>
typedef u32 sysmmu_iova_t;
typedef u32 sysmmu_pte_t;
/* We do not consider super section mapping (16MB) */
#define SECT_ORDER 20
#define LPAGE_ORDER 16
#define SPAGE_ORDER 12
#define SECT_SIZE (1 << SECT_ORDER)
#define LPAGE_SIZE (1 << LPAGE_ORDER)
#define SPAGE_SIZE (1 << SPAGE_ORDER)
#define SECT_MASK (~(SECT_SIZE - 1))
#define LPAGE_MASK (~(LPAGE_SIZE - 1))
#define SPAGE_MASK (~(SPAGE_SIZE - 1))
#define lv1ent_fault(sent) ((*(sent) == ZERO_LV2LINK) || \
((*(sent) & 3) == 0) || ((*(sent) & 3) == 3))
#define lv1ent_zero(sent) (*(sent) == ZERO_LV2LINK)
#define lv1ent_page_zero(sent) ((*(sent) & 3) == 1)
#define lv1ent_page(sent) ((*(sent) != ZERO_LV2LINK) && \
((*(sent) & 3) == 1))
#define lv1ent_section(sent) ((*(sent) & 3) == 2)
#define lv2ent_fault(pent) ((*(pent) & 3) == 0)
#define lv2ent_small(pent) ((*(pent) & 2) == 2)
#define lv2ent_large(pent) ((*(pent) & 3) == 1)
/*
* v1.x - v3.x SYSMMU supports 32bit physical and 32bit virtual address spaces
* v5.0 introduced support for 36bit physical address space by shifting
* all page entry values by 4 bits.
* All SYSMMU controllers in the system support the address spaces of the same
* size, so PG_ENT_SHIFT can be initialized on first SYSMMU probe to proper
* value (0 or 4).
*/
static short PG_ENT_SHIFT = -1;
#define SYSMMU_PG_ENT_SHIFT 0
#define SYSMMU_V5_PG_ENT_SHIFT 4
static const sysmmu_pte_t *LV1_PROT;
static const sysmmu_pte_t SYSMMU_LV1_PROT[] = {
((0 << 15) | (0 << 10)), /* no access */
((1 << 15) | (1 << 10)), /* IOMMU_READ only */
((0 << 15) | (1 << 10)), /* IOMMU_WRITE not supported, use read/write */
((0 << 15) | (1 << 10)), /* IOMMU_READ | IOMMU_WRITE */
};
static const sysmmu_pte_t SYSMMU_V5_LV1_PROT[] = {
(0 << 4), /* no access */
(1 << 4), /* IOMMU_READ only */
(2 << 4), /* IOMMU_WRITE only */
(3 << 4), /* IOMMU_READ | IOMMU_WRITE */
};
static const sysmmu_pte_t *LV2_PROT;
static const sysmmu_pte_t SYSMMU_LV2_PROT[] = {
((0 << 9) | (0 << 4)), /* no access */
((1 << 9) | (1 << 4)), /* IOMMU_READ only */
((0 << 9) | (1 << 4)), /* IOMMU_WRITE not supported, use read/write */
((0 << 9) | (1 << 4)), /* IOMMU_READ | IOMMU_WRITE */
};
static const sysmmu_pte_t SYSMMU_V5_LV2_PROT[] = {
(0 << 2), /* no access */
(1 << 2), /* IOMMU_READ only */
(2 << 2), /* IOMMU_WRITE only */
(3 << 2), /* IOMMU_READ | IOMMU_WRITE */
};
#define SYSMMU_SUPPORTED_PROT_BITS (IOMMU_READ | IOMMU_WRITE)
#define sect_to_phys(ent) (((phys_addr_t) ent) << PG_ENT_SHIFT)
#define section_phys(sent) (sect_to_phys(*(sent)) & SECT_MASK)
#define section_offs(iova) (iova & (SECT_SIZE - 1))
#define lpage_phys(pent) (sect_to_phys(*(pent)) & LPAGE_MASK)
#define lpage_offs(iova) (iova & (LPAGE_SIZE - 1))
#define spage_phys(pent) (sect_to_phys(*(pent)) & SPAGE_MASK)
#define spage_offs(iova) (iova & (SPAGE_SIZE - 1))
#define NUM_LV1ENTRIES 4096
#define NUM_LV2ENTRIES (SECT_SIZE / SPAGE_SIZE)
static u32 lv1ent_offset(sysmmu_iova_t iova)
{
return iova >> SECT_ORDER;
}
static u32 lv2ent_offset(sysmmu_iova_t iova)
{
return (iova >> SPAGE_ORDER) & (NUM_LV2ENTRIES - 1);
}
#define LV1TABLE_SIZE (NUM_LV1ENTRIES * sizeof(sysmmu_pte_t))
#define LV2TABLE_SIZE (NUM_LV2ENTRIES * sizeof(sysmmu_pte_t))
#define SPAGES_PER_LPAGE (LPAGE_SIZE / SPAGE_SIZE)
#define lv2table_base(sent) (sect_to_phys(*(sent) & 0xFFFFFFC0))
#define mk_lv1ent_sect(pa, prot) ((pa >> PG_ENT_SHIFT) | LV1_PROT[prot] | 2)
#define mk_lv1ent_page(pa) ((pa >> PG_ENT_SHIFT) | 1)
#define mk_lv2ent_lpage(pa, prot) ((pa >> PG_ENT_SHIFT) | LV2_PROT[prot] | 1)
#define mk_lv2ent_spage(pa, prot) ((pa >> PG_ENT_SHIFT) | LV2_PROT[prot] | 2)
#define CTRL_ENABLE 0x5
#define CTRL_BLOCK 0x7
#define CTRL_DISABLE 0x0
#define CFG_LRU 0x1
#define CFG_EAP (1 << 2)
#define CFG_QOS(n) ((n & 0xF) << 7)
#define CFG_ACGEN (1 << 24) /* System MMU 3.3 only */
#define CFG_SYSSEL (1 << 22) /* System MMU 3.2 only */
#define CFG_FLPDCACHE (1 << 20) /* System MMU 3.2+ only */
/* common registers */
#define REG_MMU_CTRL 0x000
#define REG_MMU_CFG 0x004
#define REG_MMU_STATUS 0x008
#define REG_MMU_VERSION 0x034
#define MMU_MAJ_VER(val) ((val) >> 7)
#define MMU_MIN_VER(val) ((val) & 0x7F)
#define MMU_RAW_VER(reg) (((reg) >> 21) & ((1 << 11) - 1)) /* 11 bits */
#define MAKE_MMU_VER(maj, min) ((((maj) & 0xF) << 7) | ((min) & 0x7F))
/* v1.x - v3.x registers */
#define REG_MMU_FLUSH 0x00C
#define REG_MMU_FLUSH_ENTRY 0x010
#define REG_PT_BASE_ADDR 0x014
#define REG_INT_STATUS 0x018
#define REG_INT_CLEAR 0x01C
#define REG_PAGE_FAULT_ADDR 0x024
#define REG_AW_FAULT_ADDR 0x028
#define REG_AR_FAULT_ADDR 0x02C
#define REG_DEFAULT_SLAVE_ADDR 0x030
/* v5.x registers */
#define REG_V5_PT_BASE_PFN 0x00C
#define REG_V5_MMU_FLUSH_ALL 0x010
#define REG_V5_MMU_FLUSH_ENTRY 0x014
#define REG_V5_MMU_FLUSH_RANGE 0x018
#define REG_V5_MMU_FLUSH_START 0x020
#define REG_V5_MMU_FLUSH_END 0x024
#define REG_V5_INT_STATUS 0x060
#define REG_V5_INT_CLEAR 0x064
#define REG_V5_FAULT_AR_VA 0x070
#define REG_V5_FAULT_AW_VA 0x080
#define has_sysmmu(dev) (dev->archdata.iommu != NULL)
static struct device *dma_dev;
static struct kmem_cache *lv2table_kmem_cache;
static sysmmu_pte_t *zero_lv2_table;
#define ZERO_LV2LINK mk_lv1ent_page(virt_to_phys(zero_lv2_table))
static sysmmu_pte_t *section_entry(sysmmu_pte_t *pgtable, sysmmu_iova_t iova)
{
return pgtable + lv1ent_offset(iova);
}
static sysmmu_pte_t *page_entry(sysmmu_pte_t *sent, sysmmu_iova_t iova)
{
return (sysmmu_pte_t *)phys_to_virt(
lv2table_base(sent)) + lv2ent_offset(iova);
}
/*
* IOMMU fault information register
*/
struct sysmmu_fault_info {
unsigned int bit; /* bit number in STATUS register */
unsigned short addr_reg; /* register to read VA fault address */
const char *name; /* human readable fault name */
unsigned int type; /* fault type for report_iommu_fault */
};
static const struct sysmmu_fault_info sysmmu_faults[] = {
{ 0, REG_PAGE_FAULT_ADDR, "PAGE", IOMMU_FAULT_READ },
{ 1, REG_AR_FAULT_ADDR, "AR MULTI-HIT", IOMMU_FAULT_READ },
{ 2, REG_AW_FAULT_ADDR, "AW MULTI-HIT", IOMMU_FAULT_WRITE },
{ 3, REG_DEFAULT_SLAVE_ADDR, "BUS ERROR", IOMMU_FAULT_READ },
{ 4, REG_AR_FAULT_ADDR, "AR SECURITY PROTECTION", IOMMU_FAULT_READ },
{ 5, REG_AR_FAULT_ADDR, "AR ACCESS PROTECTION", IOMMU_FAULT_READ },
{ 6, REG_AW_FAULT_ADDR, "AW SECURITY PROTECTION", IOMMU_FAULT_WRITE },
{ 7, REG_AW_FAULT_ADDR, "AW ACCESS PROTECTION", IOMMU_FAULT_WRITE },
};
static const struct sysmmu_fault_info sysmmu_v5_faults[] = {
{ 0, REG_V5_FAULT_AR_VA, "AR PTW", IOMMU_FAULT_READ },
{ 1, REG_V5_FAULT_AR_VA, "AR PAGE", IOMMU_FAULT_READ },
{ 2, REG_V5_FAULT_AR_VA, "AR MULTI-HIT", IOMMU_FAULT_READ },
{ 3, REG_V5_FAULT_AR_VA, "AR ACCESS PROTECTION", IOMMU_FAULT_READ },
{ 4, REG_V5_FAULT_AR_VA, "AR SECURITY PROTECTION", IOMMU_FAULT_READ },
{ 16, REG_V5_FAULT_AW_VA, "AW PTW", IOMMU_FAULT_WRITE },
{ 17, REG_V5_FAULT_AW_VA, "AW PAGE", IOMMU_FAULT_WRITE },
{ 18, REG_V5_FAULT_AW_VA, "AW MULTI-HIT", IOMMU_FAULT_WRITE },
{ 19, REG_V5_FAULT_AW_VA, "AW ACCESS PROTECTION", IOMMU_FAULT_WRITE },
{ 20, REG_V5_FAULT_AW_VA, "AW SECURITY PROTECTION", IOMMU_FAULT_WRITE },
};
/*
* This structure is attached to dev.archdata.iommu of the master device
* on device add, contains a list of SYSMMU controllers defined by device tree,
* which are bound to given master device. It is usually referenced by 'owner'
* pointer.
*/
struct exynos_iommu_owner {
struct list_head controllers; /* list of sysmmu_drvdata.owner_node */
struct iommu_domain *domain; /* domain this device is attached */
struct mutex rpm_lock; /* for runtime pm of all sysmmus */
};
/*
* This structure exynos specific generalization of struct iommu_domain.
* It contains list of SYSMMU controllers from all master devices, which has
* been attached to this domain and page tables of IO address space defined by
* it. It is usually referenced by 'domain' pointer.
*/
struct exynos_iommu_domain {
struct list_head clients; /* list of sysmmu_drvdata.domain_node */
sysmmu_pte_t *pgtable; /* lv1 page table, 16KB */
short *lv2entcnt; /* free lv2 entry counter for each section */
spinlock_t lock; /* lock for modyfying list of clients */
spinlock_t pgtablelock; /* lock for modifying page table @ pgtable */
struct iommu_domain domain; /* generic domain data structure */
};
/*
* This structure hold all data of a single SYSMMU controller, this includes
* hw resources like registers and clocks, pointers and list nodes to connect
* it to all other structures, internal state and parameters read from device
* tree. It is usually referenced by 'data' pointer.
*/
struct sysmmu_drvdata {
struct device *sysmmu; /* SYSMMU controller device */
struct device *master; /* master device (owner) */
struct device_link *link; /* runtime PM link to master */
void __iomem *sfrbase; /* our registers */
struct clk *clk; /* SYSMMU's clock */
struct clk *aclk; /* SYSMMU's aclk clock */
struct clk *pclk; /* SYSMMU's pclk clock */
struct clk *clk_master; /* master's device clock */
spinlock_t lock; /* lock for modyfying state */
bool active; /* current status */
struct exynos_iommu_domain *domain; /* domain we belong to */
struct list_head domain_node; /* node for domain clients list */
struct list_head owner_node; /* node for owner controllers list */
phys_addr_t pgtable; /* assigned page table structure */
unsigned int version; /* our version */
struct iommu_device iommu; /* IOMMU core handle */
};
static struct exynos_iommu_domain *to_exynos_domain(struct iommu_domain *dom)
{
return container_of(dom, struct exynos_iommu_domain, domain);
}
static void sysmmu_unblock(struct sysmmu_drvdata *data)
{
writel(CTRL_ENABLE, data->sfrbase + REG_MMU_CTRL);
}
static bool sysmmu_block(struct sysmmu_drvdata *data)
{
int i = 120;
writel(CTRL_BLOCK, data->sfrbase + REG_MMU_CTRL);
while ((i > 0) && !(readl(data->sfrbase + REG_MMU_STATUS) & 1))
--i;
if (!(readl(data->sfrbase + REG_MMU_STATUS) & 1)) {
sysmmu_unblock(data);
return false;
}
return true;
}
static void __sysmmu_tlb_invalidate(struct sysmmu_drvdata *data)
{
if (MMU_MAJ_VER(data->version) < 5)
writel(0x1, data->sfrbase + REG_MMU_FLUSH);
else
writel(0x1, data->sfrbase + REG_V5_MMU_FLUSH_ALL);
}
static void __sysmmu_tlb_invalidate_entry(struct sysmmu_drvdata *data,
sysmmu_iova_t iova, unsigned int num_inv)
{
unsigned int i;
if (MMU_MAJ_VER(data->version) < 5) {
for (i = 0; i < num_inv; i++) {
writel((iova & SPAGE_MASK) | 1,
data->sfrbase + REG_MMU_FLUSH_ENTRY);
iova += SPAGE_SIZE;
}
} else {
if (num_inv == 1) {
writel((iova & SPAGE_MASK) | 1,
data->sfrbase + REG_V5_MMU_FLUSH_ENTRY);
} else {
writel((iova & SPAGE_MASK),
data->sfrbase + REG_V5_MMU_FLUSH_START);
writel((iova & SPAGE_MASK) + (num_inv - 1) * SPAGE_SIZE,
data->sfrbase + REG_V5_MMU_FLUSH_END);
writel(1, data->sfrbase + REG_V5_MMU_FLUSH_RANGE);
}
}
}
static void __sysmmu_set_ptbase(struct sysmmu_drvdata *data, phys_addr_t pgd)
{
if (MMU_MAJ_VER(data->version) < 5)
writel(pgd, data->sfrbase + REG_PT_BASE_ADDR);
else
writel(pgd >> PAGE_SHIFT,
data->sfrbase + REG_V5_PT_BASE_PFN);
__sysmmu_tlb_invalidate(data);
}
static void __sysmmu_enable_clocks(struct sysmmu_drvdata *data)
{
BUG_ON(clk_prepare_enable(data->clk_master));
BUG_ON(clk_prepare_enable(data->clk));
BUG_ON(clk_prepare_enable(data->pclk));
BUG_ON(clk_prepare_enable(data->aclk));
}
static void __sysmmu_disable_clocks(struct sysmmu_drvdata *data)
{
clk_disable_unprepare(data->aclk);
clk_disable_unprepare(data->pclk);
clk_disable_unprepare(data->clk);
clk_disable_unprepare(data->clk_master);
}
static void __sysmmu_get_version(struct sysmmu_drvdata *data)
{
u32 ver;
__sysmmu_enable_clocks(data);
ver = readl(data->sfrbase + REG_MMU_VERSION);
/* controllers on some SoCs don't report proper version */
if (ver == 0x80000001u)
data->version = MAKE_MMU_VER(1, 0);
else
data->version = MMU_RAW_VER(ver);
dev_dbg(data->sysmmu, "hardware version: %d.%d\n",
MMU_MAJ_VER(data->version), MMU_MIN_VER(data->version));
__sysmmu_disable_clocks(data);
}
static void show_fault_information(struct sysmmu_drvdata *data,
const struct sysmmu_fault_info *finfo,
sysmmu_iova_t fault_addr)
{
sysmmu_pte_t *ent;
dev_err(data->sysmmu, "%s: %s FAULT occurred at %#x\n",
dev_name(data->master), finfo->name, fault_addr);
dev_dbg(data->sysmmu, "Page table base: %pa\n", &data->pgtable);
ent = section_entry(phys_to_virt(data->pgtable), fault_addr);
dev_dbg(data->sysmmu, "\tLv1 entry: %#x\n", *ent);
if (lv1ent_page(ent)) {
ent = page_entry(ent, fault_addr);
dev_dbg(data->sysmmu, "\t Lv2 entry: %#x\n", *ent);
}
}
static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
{
/* SYSMMU is in blocked state when interrupt occurred. */
struct sysmmu_drvdata *data = dev_id;
const struct sysmmu_fault_info *finfo;
unsigned int i, n, itype;
sysmmu_iova_t fault_addr = -1;
unsigned short reg_status, reg_clear;
int ret = -ENOSYS;
WARN_ON(!data->active);
if (MMU_MAJ_VER(data->version) < 5) {
reg_status = REG_INT_STATUS;
reg_clear = REG_INT_CLEAR;
finfo = sysmmu_faults;
n = ARRAY_SIZE(sysmmu_faults);
} else {
reg_status = REG_V5_INT_STATUS;
reg_clear = REG_V5_INT_CLEAR;
finfo = sysmmu_v5_faults;
n = ARRAY_SIZE(sysmmu_v5_faults);
}
spin_lock(&data->lock);
clk_enable(data->clk_master);
itype = __ffs(readl(data->sfrbase + reg_status));
for (i = 0; i < n; i++, finfo++)
if (finfo->bit == itype)
break;
/* unknown/unsupported fault */
BUG_ON(i == n);
/* print debug message */
fault_addr = readl(data->sfrbase + finfo->addr_reg);
show_fault_information(data, finfo, fault_addr);
if (data->domain)
ret = report_iommu_fault(&data->domain->domain,
data->master, fault_addr, finfo->type);
/* fault is not recovered by fault handler */
BUG_ON(ret != 0);
writel(1 << itype, data->sfrbase + reg_clear);
sysmmu_unblock(data);
clk_disable(data->clk_master);
spin_unlock(&data->lock);
return IRQ_HANDLED;
}
static void __sysmmu_disable(struct sysmmu_drvdata *data)
{
unsigned long flags;
clk_enable(data->clk_master);
spin_lock_irqsave(&data->lock, flags);
writel(CTRL_DISABLE, data->sfrbase + REG_MMU_CTRL);
writel(0, data->sfrbase + REG_MMU_CFG);
data->active = false;
spin_unlock_irqrestore(&data->lock, flags);
__sysmmu_disable_clocks(data);
}
static void __sysmmu_init_config(struct sysmmu_drvdata *data)
{
unsigned int cfg;
if (data->version <= MAKE_MMU_VER(3, 1))
cfg = CFG_LRU | CFG_QOS(15);
else if (data->version <= MAKE_MMU_VER(3, 2))
cfg = CFG_LRU | CFG_QOS(15) | CFG_FLPDCACHE | CFG_SYSSEL;
else
cfg = CFG_QOS(15) | CFG_FLPDCACHE | CFG_ACGEN;
cfg |= CFG_EAP; /* enable access protection bits check */
writel(cfg, data->sfrbase + REG_MMU_CFG);
}
static void __sysmmu_enable(struct sysmmu_drvdata *data)
{
unsigned long flags;
__sysmmu_enable_clocks(data);
spin_lock_irqsave(&data->lock, flags);
writel(CTRL_BLOCK, data->sfrbase + REG_MMU_CTRL);
__sysmmu_init_config(data);
__sysmmu_set_ptbase(data, data->pgtable);
writel(CTRL_ENABLE, data->sfrbase + REG_MMU_CTRL);
data->active = true;
spin_unlock_irqrestore(&data->lock, flags);
/*
* SYSMMU driver keeps master's clock enabled only for the short
* time, while accessing the registers. For performing address
* translation during DMA transaction it relies on the client
* driver to enable it.
*/
clk_disable(data->clk_master);
}
static void sysmmu_tlb_invalidate_flpdcache(struct sysmmu_drvdata *data,
sysmmu_iova_t iova)
{
unsigned long flags;
spin_lock_irqsave(&data->lock, flags);
if (data->active && data->version >= MAKE_MMU_VER(3, 3)) {
clk_enable(data->clk_master);
if (sysmmu_block(data)) {
if (data->version >= MAKE_MMU_VER(5, 0))
__sysmmu_tlb_invalidate(data);
else
__sysmmu_tlb_invalidate_entry(data, iova, 1);
sysmmu_unblock(data);
}
clk_disable(data->clk_master);
}
spin_unlock_irqrestore(&data->lock, flags);
}
static void sysmmu_tlb_invalidate_entry(struct sysmmu_drvdata *data,
sysmmu_iova_t iova, size_t size)
{
unsigned long flags;
spin_lock_irqsave(&data->lock, flags);
if (data->active) {
unsigned int num_inv = 1;
clk_enable(data->clk_master);
/*
* L2TLB invalidation required
* 4KB page: 1 invalidation
* 64KB page: 16 invalidations
* 1MB page: 64 invalidations
* because it is set-associative TLB
* with 8-way and 64 sets.
* 1MB page can be cached in one of all sets.
* 64KB page can be one of 16 consecutive sets.
*/
if (MMU_MAJ_VER(data->version) == 2)
num_inv = min_t(unsigned int, size / PAGE_SIZE, 64);
if (sysmmu_block(data)) {
__sysmmu_tlb_invalidate_entry(data, iova, num_inv);
sysmmu_unblock(data);
}
clk_disable(data->clk_master);
}
spin_unlock_irqrestore(&data->lock, flags);
}
static const struct iommu_ops exynos_iommu_ops;
static int exynos_sysmmu_probe(struct platform_device *pdev)
{
int irq, ret;
struct device *dev = &pdev->dev;
struct sysmmu_drvdata *data;
struct resource *res;
data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
data->sfrbase = devm_ioremap_resource(dev, res);
if (IS_ERR(data->sfrbase))
return PTR_ERR(data->sfrbase);
irq = platform_get_irq(pdev, 0);
if (irq <= 0)
return irq;
ret = devm_request_irq(dev, irq, exynos_sysmmu_irq, 0,
dev_name(dev), data);
if (ret) {
dev_err(dev, "Unabled to register handler of irq %d\n", irq);
return ret;
}
data->clk = devm_clk_get(dev, "sysmmu");
if (PTR_ERR(data->clk) == -ENOENT)
data->clk = NULL;
else if (IS_ERR(data->clk))
return PTR_ERR(data->clk);
data->aclk = devm_clk_get(dev, "aclk");
if (PTR_ERR(data->aclk) == -ENOENT)
data->aclk = NULL;
else if (IS_ERR(data->aclk))
return PTR_ERR(data->aclk);
data->pclk = devm_clk_get(dev, "pclk");
if (PTR_ERR(data->pclk) == -ENOENT)
data->pclk = NULL;
else if (IS_ERR(data->pclk))
return PTR_ERR(data->pclk);
if (!data->clk && (!data->aclk || !data->pclk)) {
dev_err(dev, "Failed to get device clock(s)!\n");
return -ENOSYS;
}
data->clk_master = devm_clk_get(dev, "master");
if (PTR_ERR(data->clk_master) == -ENOENT)
data->clk_master = NULL;
else if (IS_ERR(data->clk_master))
return PTR_ERR(data->clk_master);
data->sysmmu = dev;
spin_lock_init(&data->lock);
ret = iommu_device_sysfs_add(&data->iommu, &pdev->dev, NULL,
dev_name(data->sysmmu));
if (ret)
return ret;
iommu_device_set_ops(&data->iommu, &exynos_iommu_ops);
iommu_device_set_fwnode(&data->iommu, &dev->of_node->fwnode);
ret = iommu_device_register(&data->iommu);
if (ret)
return ret;
platform_set_drvdata(pdev, data);
__sysmmu_get_version(data);
if (PG_ENT_SHIFT < 0) {
if (MMU_MAJ_VER(data->version) < 5) {
PG_ENT_SHIFT = SYSMMU_PG_ENT_SHIFT;
LV1_PROT = SYSMMU_LV1_PROT;
LV2_PROT = SYSMMU_LV2_PROT;
} else {
PG_ENT_SHIFT = SYSMMU_V5_PG_ENT_SHIFT;
LV1_PROT = SYSMMU_V5_LV1_PROT;
LV2_PROT = SYSMMU_V5_LV2_PROT;
}
}
/*
* use the first registered sysmmu device for performing
* dma mapping operations on iommu page tables (cpu cache flush)
*/
if (!dma_dev)
dma_dev = &pdev->dev;
pm_runtime_enable(dev);
return 0;
}
static int __maybe_unused exynos_sysmmu_suspend(struct device *dev)
{
struct sysmmu_drvdata *data = dev_get_drvdata(dev);
struct device *master = data->master;
if (master) {
struct exynos_iommu_owner *owner = master->archdata.iommu;
mutex_lock(&owner->rpm_lock);
if (data->domain) {
dev_dbg(data->sysmmu, "saving state\n");
__sysmmu_disable(data);
}
mutex_unlock(&owner->rpm_lock);
}
return 0;
}
static int __maybe_unused exynos_sysmmu_resume(struct device *dev)
{
struct sysmmu_drvdata *data = dev_get_drvdata(dev);
struct device *master = data->master;
if (master) {
struct exynos_iommu_owner *owner = master->archdata.iommu;
mutex_lock(&owner->rpm_lock);
if (data->domain) {
dev_dbg(data->sysmmu, "restoring state\n");
__sysmmu_enable(data);
}
mutex_unlock(&owner->rpm_lock);
}
return 0;
}
static const struct dev_pm_ops sysmmu_pm_ops = {
SET_RUNTIME_PM_OPS(exynos_sysmmu_suspend, exynos_sysmmu_resume, NULL)
SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
pm_runtime_force_resume)
};
static const struct of_device_id sysmmu_of_match[] = {
{ .compatible = "samsung,exynos-sysmmu", },
{ },
};
static struct platform_driver exynos_sysmmu_driver __refdata = {
.probe = exynos_sysmmu_probe,
.driver = {
.name = "exynos-sysmmu",
.of_match_table = sysmmu_of_match,
.pm = &sysmmu_pm_ops,
.suppress_bind_attrs = true,
}
};
static inline void update_pte(sysmmu_pte_t *ent, sysmmu_pte_t val)
{
dma_sync_single_for_cpu(dma_dev, virt_to_phys(ent), sizeof(*ent),
DMA_TO_DEVICE);
*ent = cpu_to_le32(val);
dma_sync_single_for_device(dma_dev, virt_to_phys(ent), sizeof(*ent),
DMA_TO_DEVICE);
}
static struct iommu_domain *exynos_iommu_domain_alloc(unsigned type)
{
struct exynos_iommu_domain *domain;
dma_addr_t handle;
int i;
/* Check if correct PTE offsets are initialized */
BUG_ON(PG_ENT_SHIFT < 0 || !dma_dev);
domain = kzalloc(sizeof(*domain), GFP_KERNEL);
if (!domain)
return NULL;
if (type == IOMMU_DOMAIN_DMA) {
if (iommu_get_dma_cookie(&domain->domain) != 0)
goto err_pgtable;
} else if (type != IOMMU_DOMAIN_UNMANAGED) {
goto err_pgtable;
}
domain->pgtable = (sysmmu_pte_t *)__get_free_pages(GFP_KERNEL, 2);
if (!domain->pgtable)
goto err_dma_cookie;
domain->lv2entcnt = (short *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, 1);
if (!domain->lv2entcnt)
goto err_counter;
/* Workaround for System MMU v3.3 to prevent caching 1MiB mapping */
for (i = 0; i < NUM_LV1ENTRIES; i++)
domain->pgtable[i] = ZERO_LV2LINK;
handle = dma_map_single(dma_dev, domain->pgtable, LV1TABLE_SIZE,
DMA_TO_DEVICE);
/* For mapping page table entries we rely on dma == phys */
BUG_ON(handle != virt_to_phys(domain->pgtable));
if (dma_mapping_error(dma_dev, handle))
goto err_lv2ent;
spin_lock_init(&domain->lock);
spin_lock_init(&domain->pgtablelock);
INIT_LIST_HEAD(&domain->clients);
domain->domain.geometry.aperture_start = 0;
domain->domain.geometry.aperture_end = ~0UL;
domain->domain.geometry.force_aperture = true;
return &domain->domain;
err_lv2ent:
free_pages((unsigned long)domain->lv2entcnt, 1);
err_counter:
free_pages((unsigned long)domain->pgtable, 2);
err_dma_cookie:
if (type == IOMMU_DOMAIN_DMA)
iommu_put_dma_cookie(&domain->domain);
err_pgtable:
kfree(domain);
return NULL;
}
static void exynos_iommu_domain_free(struct iommu_domain *iommu_domain)
{
struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
struct sysmmu_drvdata *data, *next;
unsigned long flags;
int i;
WARN_ON(!list_empty(&domain->clients));
spin_lock_irqsave(&domain->lock, flags);
list_for_each_entry_safe(data, next, &domain->clients, domain_node) {
spin_lock(&data->lock);
__sysmmu_disable(data);
data->pgtable = 0;
data->domain = NULL;
list_del_init(&data->domain_node);
spin_unlock(&data->lock);
}
spin_unlock_irqrestore(&domain->lock, flags);
if (iommu_domain->type == IOMMU_DOMAIN_DMA)
iommu_put_dma_cookie(iommu_domain);
dma_unmap_single(dma_dev, virt_to_phys(domain->pgtable), LV1TABLE_SIZE,
DMA_TO_DEVICE);
for (i = 0; i < NUM_LV1ENTRIES; i++)
if (lv1ent_page(domain->pgtable + i)) {
phys_addr_t base = lv2table_base(domain->pgtable + i);
dma_unmap_single(dma_dev, base, LV2TABLE_SIZE,
DMA_TO_DEVICE);
kmem_cache_free(lv2table_kmem_cache,
phys_to_virt(base));
}
free_pages((unsigned long)domain->pgtable, 2);
free_pages((unsigned long)domain->lv2entcnt, 1);
kfree(domain);
}
static void exynos_iommu_detach_device(struct iommu_domain *iommu_domain,
struct device *dev)
{
struct exynos_iommu_owner *owner = dev->archdata.iommu;
struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
phys_addr_t pagetable = virt_to_phys(domain->pgtable);
struct sysmmu_drvdata *data, *next;
unsigned long flags;
if (!has_sysmmu(dev) || owner->domain != iommu_domain)
return;
mutex_lock(&owner->rpm_lock);
list_for_each_entry(data, &owner->controllers, owner_node) {
pm_runtime_get_noresume(data->sysmmu);
if (pm_runtime_active(data->sysmmu))
__sysmmu_disable(data);
pm_runtime_put(data->sysmmu);
}
spin_lock_irqsave(&domain->lock, flags);
list_for_each_entry_safe(data, next, &domain->clients, domain_node) {
spin_lock(&data->lock);
data->pgtable = 0;
data->domain = NULL;
list_del_init(&data->domain_node);
spin_unlock(&data->lock);
}
owner->domain = NULL;
spin_unlock_irqrestore(&domain->lock, flags);
mutex_unlock(&owner->rpm_lock);
dev_dbg(dev, "%s: Detached IOMMU with pgtable %pa\n", __func__,
&pagetable);
}
static int exynos_iommu_attach_device(struct iommu_domain *iommu_domain,
struct device *dev)
{
struct exynos_iommu_owner *owner = dev->archdata.iommu;
struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
struct sysmmu_drvdata *data;
phys_addr_t pagetable = virt_to_phys(domain->pgtable);
unsigned long flags;
if (!has_sysmmu(dev))
return -ENODEV;
if (owner->domain)
exynos_iommu_detach_device(owner->domain, dev);
mutex_lock(&owner->rpm_lock);
spin_lock_irqsave(&domain->lock, flags);
list_for_each_entry(data, &owner->controllers, owner_node) {
spin_lock(&data->lock);
data->pgtable = pagetable;
data->domain = domain;
list_add_tail(&data->domain_node, &domain->clients);
spin_unlock(&data->lock);
}
owner->domain = iommu_domain;
spin_unlock_irqrestore(&domain->lock, flags);
list_for_each_entry(data, &owner->controllers, owner_node) {
pm_runtime_get_noresume(data->sysmmu);
if (pm_runtime_active(data->sysmmu))
__sysmmu_enable(data);
pm_runtime_put(data->sysmmu);
}
mutex_unlock(&owner->rpm_lock);
dev_dbg(dev, "%s: Attached IOMMU with pgtable %pa\n", __func__,
&pagetable);
return 0;
}
static sysmmu_pte_t *alloc_lv2entry(struct exynos_iommu_domain *domain,
sysmmu_pte_t *sent, sysmmu_iova_t iova, short *pgcounter)
{
if (lv1ent_section(sent)) {
WARN(1, "Trying mapping on %#08x mapped with 1MiB page", iova);
return ERR_PTR(-EADDRINUSE);
}
if (lv1ent_fault(sent)) {
dma_addr_t handle;
sysmmu_pte_t *pent;
bool need_flush_flpd_cache = lv1ent_zero(sent);
pent = kmem_cache_zalloc(lv2table_kmem_cache, GFP_ATOMIC);
BUG_ON((uintptr_t)pent & (LV2TABLE_SIZE - 1));
if (!pent)
return ERR_PTR(-ENOMEM);
update_pte(sent, mk_lv1ent_page(virt_to_phys(pent)));
kmemleak_ignore(pent);
*pgcounter = NUM_LV2ENTRIES;
handle = dma_map_single(dma_dev, pent, LV2TABLE_SIZE,
DMA_TO_DEVICE);
if (dma_mapping_error(dma_dev, handle)) {
kmem_cache_free(lv2table_kmem_cache, pent);
return ERR_PTR(-EADDRINUSE);
}
/*
* If pre-fetched SLPD is a faulty SLPD in zero_l2_table,
* FLPD cache may cache the address of zero_l2_table. This
* function replaces the zero_l2_table with new L2 page table
* to write valid mappings.
* Accessing the valid area may cause page fault since FLPD
* cache may still cache zero_l2_table for the valid area
* instead of new L2 page table that has the mapping
* information of the valid area.
* Thus any replacement of zero_l2_table with other valid L2
* page table must involve FLPD cache invalidation for System
* MMU v3.3.
* FLPD cache invalidation is performed with TLB invalidation
* by VPN without blocking. It is safe to invalidate TLB without
* blocking because the target address of TLB invalidation is
* not currently mapped.
*/
if (need_flush_flpd_cache) {
struct sysmmu_drvdata *data;
spin_lock(&domain->lock);
list_for_each_entry(data, &domain->clients, domain_node)
sysmmu_tlb_invalidate_flpdcache(data, iova);
spin_unlock(&domain->lock);
}
}
return page_entry(sent, iova);
}
static int lv1set_section(struct exynos_iommu_domain *domain,
sysmmu_pte_t *sent, sysmmu_iova_t iova,
phys_addr_t paddr, int prot, short *pgcnt)
{
if (lv1ent_section(sent)) {
WARN(1, "Trying mapping on 1MiB@%#08x that is mapped",
iova);
return -EADDRINUSE;
}
if (lv1ent_page(sent)) {
if (*pgcnt != NUM_LV2ENTRIES) {
WARN(1, "Trying mapping on 1MiB@%#08x that is mapped",
iova);
return -EADDRINUSE;
}
kmem_cache_free(lv2table_kmem_cache, page_entry(sent, 0));
*pgcnt = 0;
}
update_pte(sent, mk_lv1ent_sect(paddr, prot));
spin_lock(&domain->lock);
if (lv1ent_page_zero(sent)) {
struct sysmmu_drvdata *data;
/*
* Flushing FLPD cache in System MMU v3.3 that may cache a FLPD
* entry by speculative prefetch of SLPD which has no mapping.
*/
list_for_each_entry(data, &domain->clients, domain_node)
sysmmu_tlb_invalidate_flpdcache(data, iova);
}
spin_unlock(&domain->lock);
return 0;
}
static int lv2set_page(sysmmu_pte_t *pent, phys_addr_t paddr, size_t size,
int prot, short *pgcnt)
{
if (size == SPAGE_SIZE) {
if (WARN_ON(!lv2ent_fault(pent)))
return -EADDRINUSE;
update_pte(pent, mk_lv2ent_spage(paddr, prot));
*pgcnt -= 1;
} else { /* size == LPAGE_SIZE */
int i;
dma_addr_t pent_base = virt_to_phys(pent);
dma_sync_single_for_cpu(dma_dev, pent_base,
sizeof(*pent) * SPAGES_PER_LPAGE,
DMA_TO_DEVICE);
for (i = 0; i < SPAGES_PER_LPAGE; i++, pent++) {
if (WARN_ON(!lv2ent_fault(pent))) {
if (i > 0)
memset(pent - i, 0, sizeof(*pent) * i);
return -EADDRINUSE;
}
*pent = mk_lv2ent_lpage(paddr, prot);
}
dma_sync_single_for_device(dma_dev, pent_base,
sizeof(*pent) * SPAGES_PER_LPAGE,
DMA_TO_DEVICE);
*pgcnt -= SPAGES_PER_LPAGE;
}
return 0;
}
/*
* *CAUTION* to the I/O virtual memory managers that support exynos-iommu:
*
* System MMU v3.x has advanced logic to improve address translation
* performance with caching more page table entries by a page table walk.
* However, the logic has a bug that while caching faulty page table entries,
* System MMU reports page fault if the cached fault entry is hit even though
* the fault entry is updated to a valid entry after the entry is cached.
* To prevent caching faulty page table entries which may be updated to valid
* entries later, the virtual memory manager should care about the workaround
* for the problem. The following describes the workaround.
*
* Any two consecutive I/O virtual address regions must have a hole of 128KiB
* at maximum to prevent misbehavior of System MMU 3.x (workaround for h/w bug).
*
* Precisely, any start address of I/O virtual region must be aligned with
* the following sizes for System MMU v3.1 and v3.2.
* System MMU v3.1: 128KiB
* System MMU v3.2: 256KiB
*
* Because System MMU v3.3 caches page table entries more aggressively, it needs
* more workarounds.
* - Any two consecutive I/O virtual regions must have a hole of size larger
* than or equal to 128KiB.
* - Start address of an I/O virtual region must be aligned by 128KiB.
*/
static int exynos_iommu_map(struct iommu_domain *iommu_domain,
unsigned long l_iova, phys_addr_t paddr, size_t size,
int prot)
{
struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
sysmmu_pte_t *entry;
sysmmu_iova_t iova = (sysmmu_iova_t)l_iova;
unsigned long flags;
int ret = -ENOMEM;
BUG_ON(domain->pgtable == NULL);
prot &= SYSMMU_SUPPORTED_PROT_BITS;
spin_lock_irqsave(&domain->pgtablelock, flags);
entry = section_entry(domain->pgtable, iova);
if (size == SECT_SIZE) {
ret = lv1set_section(domain, entry, iova, paddr, prot,
&domain->lv2entcnt[lv1ent_offset(iova)]);
} else {
sysmmu_pte_t *pent;
pent = alloc_lv2entry(domain, entry, iova,
&domain->lv2entcnt[lv1ent_offset(iova)]);
if (IS_ERR(pent))
ret = PTR_ERR(pent);
else
ret = lv2set_page(pent, paddr, size, prot,
&domain->lv2entcnt[lv1ent_offset(iova)]);
}
if (ret)
pr_err("%s: Failed(%d) to map %#zx bytes @ %#x\n",
__func__, ret, size, iova);
spin_unlock_irqrestore(&domain->pgtablelock, flags);
return ret;
}
static void exynos_iommu_tlb_invalidate_entry(struct exynos_iommu_domain *domain,
sysmmu_iova_t iova, size_t size)
{
struct sysmmu_drvdata *data;
unsigned long flags;
spin_lock_irqsave(&domain->lock, flags);
list_for_each_entry(data, &domain->clients, domain_node)
sysmmu_tlb_invalidate_entry(data, iova, size);
spin_unlock_irqrestore(&domain->lock, flags);
}
static size_t exynos_iommu_unmap(struct iommu_domain *iommu_domain,
unsigned long l_iova, size_t size,
struct iommu_iotlb_gather *gather)
{
struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
sysmmu_iova_t iova = (sysmmu_iova_t)l_iova;
sysmmu_pte_t *ent;
size_t err_pgsize;
unsigned long flags;
BUG_ON(domain->pgtable == NULL);
spin_lock_irqsave(&domain->pgtablelock, flags);
ent = section_entry(domain->pgtable, iova);
if (lv1ent_section(ent)) {
if (WARN_ON(size < SECT_SIZE)) {
err_pgsize = SECT_SIZE;
goto err;
}
/* workaround for h/w bug in System MMU v3.3 */
update_pte(ent, ZERO_LV2LINK);
size = SECT_SIZE;
goto done;
}
if (unlikely(lv1ent_fault(ent))) {
if (size > SECT_SIZE)
size = SECT_SIZE;
goto done;
}
/* lv1ent_page(sent) == true here */
ent = page_entry(ent, iova);
if (unlikely(lv2ent_fault(ent))) {
size = SPAGE_SIZE;
goto done;
}
if (lv2ent_small(ent)) {
update_pte(ent, 0);
size = SPAGE_SIZE;
domain->lv2entcnt[lv1ent_offset(iova)] += 1;
goto done;
}
/* lv1ent_large(ent) == true here */
if (WARN_ON(size < LPAGE_SIZE)) {
err_pgsize = LPAGE_SIZE;
goto err;
}
dma_sync_single_for_cpu(dma_dev, virt_to_phys(ent),
sizeof(*ent) * SPAGES_PER_LPAGE,
DMA_TO_DEVICE);
memset(ent, 0, sizeof(*ent) * SPAGES_PER_LPAGE);
dma_sync_single_for_device(dma_dev, virt_to_phys(ent),
sizeof(*ent) * SPAGES_PER_LPAGE,
DMA_TO_DEVICE);
size = LPAGE_SIZE;
domain->lv2entcnt[lv1ent_offset(iova)] += SPAGES_PER_LPAGE;
done:
spin_unlock_irqrestore(&domain->pgtablelock, flags);
exynos_iommu_tlb_invalidate_entry(domain, iova, size);
return size;
err:
spin_unlock_irqrestore(&domain->pgtablelock, flags);
pr_err("%s: Failed: size(%#zx) @ %#x is smaller than page size %#zx\n",
__func__, size, iova, err_pgsize);
return 0;
}
static phys_addr_t exynos_iommu_iova_to_phys(struct iommu_domain *iommu_domain,
dma_addr_t iova)
{
struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
sysmmu_pte_t *entry;
unsigned long flags;
phys_addr_t phys = 0;
spin_lock_irqsave(&domain->pgtablelock, flags);
entry = section_entry(domain->pgtable, iova);
if (lv1ent_section(entry)) {
phys = section_phys(entry) + section_offs(iova);
} else if (lv1ent_page(entry)) {
entry = page_entry(entry, iova);
if (lv2ent_large(entry))
phys = lpage_phys(entry) + lpage_offs(iova);
else if (lv2ent_small(entry))
phys = spage_phys(entry) + spage_offs(iova);
}
spin_unlock_irqrestore(&domain->pgtablelock, flags);
return phys;
}
static int exynos_iommu_add_device(struct device *dev)
{
struct exynos_iommu_owner *owner = dev->archdata.iommu;
struct sysmmu_drvdata *data;
struct iommu_group *group;
if (!has_sysmmu(dev))
return -ENODEV;
group = iommu_group_get_for_dev(dev);
if (IS_ERR(group))
return PTR_ERR(group);
list_for_each_entry(data, &owner->controllers, owner_node) {
/*
* SYSMMU will be runtime activated via device link
* (dependency) to its master device, so there are no
* direct calls to pm_runtime_get/put in this driver.
*/
data->link = device_link_add(dev, data->sysmmu,
DL_FLAG_STATELESS |
DL_FLAG_PM_RUNTIME);
}
iommu_group_put(group);
return 0;
}
static void exynos_iommu_remove_device(struct device *dev)
{
struct exynos_iommu_owner *owner = dev->archdata.iommu;
struct sysmmu_drvdata *data;
if (!has_sysmmu(dev))
return;
if (owner->domain) {
struct iommu_group *group = iommu_group_get(dev);
if (group) {
WARN_ON(owner->domain !=
iommu_group_default_domain(group));
exynos_iommu_detach_device(owner->domain, dev);
iommu_group_put(group);
}
}
iommu_group_remove_device(dev);
list_for_each_entry(data, &owner->controllers, owner_node)
device_link_del(data->link);
}
static int exynos_iommu_of_xlate(struct device *dev,
struct of_phandle_args *spec)
{
struct exynos_iommu_owner *owner = dev->archdata.iommu;
struct platform_device *sysmmu = of_find_device_by_node(spec->np);
struct sysmmu_drvdata *data, *entry;
if (!sysmmu)
return -ENODEV;
data = platform_get_drvdata(sysmmu);
if (!data)
return -ENODEV;
if (!owner) {
owner = kzalloc(sizeof(*owner), GFP_KERNEL);
if (!owner)
return -ENOMEM;
INIT_LIST_HEAD(&owner->controllers);
mutex_init(&owner->rpm_lock);
dev->archdata.iommu = owner;
}
list_for_each_entry(entry, &owner->controllers, owner_node)
if (entry == data)
return 0;
list_add_tail(&data->owner_node, &owner->controllers);
data->master = dev;
return 0;
}
static const struct iommu_ops exynos_iommu_ops = {
.domain_alloc = exynos_iommu_domain_alloc,
.domain_free = exynos_iommu_domain_free,
.attach_dev = exynos_iommu_attach_device,
.detach_dev = exynos_iommu_detach_device,
.map = exynos_iommu_map,
.unmap = exynos_iommu_unmap,
.iova_to_phys = exynos_iommu_iova_to_phys,
.device_group = generic_device_group,
.add_device = exynos_iommu_add_device,
.remove_device = exynos_iommu_remove_device,
.pgsize_bitmap = SECT_SIZE | LPAGE_SIZE | SPAGE_SIZE,
.of_xlate = exynos_iommu_of_xlate,
};
static int __init exynos_iommu_init(void)
{
struct device_node *np;
int ret;
np = of_find_matching_node(NULL, sysmmu_of_match);
if (!np)
return 0;
of_node_put(np);
lv2table_kmem_cache = kmem_cache_create("exynos-iommu-lv2table",
LV2TABLE_SIZE, LV2TABLE_SIZE, 0, NULL);
if (!lv2table_kmem_cache) {
pr_err("%s: Failed to create kmem cache\n", __func__);
return -ENOMEM;
}
ret = platform_driver_register(&exynos_sysmmu_driver);
if (ret) {
pr_err("%s: Failed to register driver\n", __func__);
goto err_reg_driver;
}
zero_lv2_table = kmem_cache_zalloc(lv2table_kmem_cache, GFP_KERNEL);
if (zero_lv2_table == NULL) {
pr_err("%s: Failed to allocate zero level2 page table\n",
__func__);
ret = -ENOMEM;
goto err_zero_lv2;
}
ret = bus_set_iommu(&platform_bus_type, &exynos_iommu_ops);
if (ret) {
pr_err("%s: Failed to register exynos-iommu driver.\n",
__func__);
goto err_set_iommu;
}
return 0;
err_set_iommu:
kmem_cache_free(lv2table_kmem_cache, zero_lv2_table);
err_zero_lv2:
platform_driver_unregister(&exynos_sysmmu_driver);
err_reg_driver:
kmem_cache_destroy(lv2table_kmem_cache);
return ret;
}
core_initcall(exynos_iommu_init);