linux/drivers/iommu/tegra-smmu.c

1187 lines
28 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2011-2014 NVIDIA CORPORATION. All rights reserved.
*/
#include <linux/bitops.h>
#include <linux/debugfs.h>
#include <linux/err.h>
#include <linux/iommu.h>
#include <linux/kernel.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/pci.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/dma-mapping.h>
#include <soc/tegra/ahb.h>
#include <soc/tegra/mc.h>
struct tegra_smmu_group {
struct list_head list;
struct tegra_smmu *smmu;
const struct tegra_smmu_group_soc *soc;
struct iommu_group *group;
unsigned int swgroup;
};
struct tegra_smmu {
void __iomem *regs;
struct device *dev;
struct tegra_mc *mc;
const struct tegra_smmu_soc *soc;
struct list_head groups;
unsigned long pfn_mask;
unsigned long tlb_mask;
unsigned long *asids;
struct mutex lock;
struct list_head list;
struct dentry *debugfs;
struct iommu_device iommu; /* IOMMU Core code handle */
};
struct tegra_smmu_as {
struct iommu_domain domain;
struct tegra_smmu *smmu;
unsigned int use_count;
spinlock_t lock;
u32 *count;
struct page **pts;
struct page *pd;
dma_addr_t pd_dma;
unsigned id;
u32 attr;
};
static struct tegra_smmu_as *to_smmu_as(struct iommu_domain *dom)
{
return container_of(dom, struct tegra_smmu_as, domain);
}
static inline void smmu_writel(struct tegra_smmu *smmu, u32 value,
unsigned long offset)
{
writel(value, smmu->regs + offset);
}
static inline u32 smmu_readl(struct tegra_smmu *smmu, unsigned long offset)
{
return readl(smmu->regs + offset);
}
#define SMMU_CONFIG 0x010
#define SMMU_CONFIG_ENABLE (1 << 0)
#define SMMU_TLB_CONFIG 0x14
#define SMMU_TLB_CONFIG_HIT_UNDER_MISS (1 << 29)
#define SMMU_TLB_CONFIG_ROUND_ROBIN_ARBITRATION (1 << 28)
#define SMMU_TLB_CONFIG_ACTIVE_LINES(smmu) \
((smmu)->soc->num_tlb_lines & (smmu)->tlb_mask)
#define SMMU_PTC_CONFIG 0x18
#define SMMU_PTC_CONFIG_ENABLE (1 << 29)
#define SMMU_PTC_CONFIG_REQ_LIMIT(x) (((x) & 0x0f) << 24)
#define SMMU_PTC_CONFIG_INDEX_MAP(x) ((x) & 0x3f)
#define SMMU_PTB_ASID 0x01c
#define SMMU_PTB_ASID_VALUE(x) ((x) & 0x7f)
#define SMMU_PTB_DATA 0x020
#define SMMU_PTB_DATA_VALUE(dma, attr) ((dma) >> 12 | (attr))
#define SMMU_MK_PDE(dma, attr) ((dma) >> SMMU_PTE_SHIFT | (attr))
#define SMMU_TLB_FLUSH 0x030
#define SMMU_TLB_FLUSH_VA_MATCH_ALL (0 << 0)
#define SMMU_TLB_FLUSH_VA_MATCH_SECTION (2 << 0)
#define SMMU_TLB_FLUSH_VA_MATCH_GROUP (3 << 0)
#define SMMU_TLB_FLUSH_VA_SECTION(addr) ((((addr) & 0xffc00000) >> 12) | \
SMMU_TLB_FLUSH_VA_MATCH_SECTION)
#define SMMU_TLB_FLUSH_VA_GROUP(addr) ((((addr) & 0xffffc000) >> 12) | \
SMMU_TLB_FLUSH_VA_MATCH_GROUP)
#define SMMU_TLB_FLUSH_ASID_MATCH (1 << 31)
#define SMMU_PTC_FLUSH 0x034
#define SMMU_PTC_FLUSH_TYPE_ALL (0 << 0)
#define SMMU_PTC_FLUSH_TYPE_ADR (1 << 0)
#define SMMU_PTC_FLUSH_HI 0x9b8
#define SMMU_PTC_FLUSH_HI_MASK 0x3
/* per-SWGROUP SMMU_*_ASID register */
#define SMMU_ASID_ENABLE (1 << 31)
#define SMMU_ASID_MASK 0x7f
#define SMMU_ASID_VALUE(x) ((x) & SMMU_ASID_MASK)
/* page table definitions */
#define SMMU_NUM_PDE 1024
#define SMMU_NUM_PTE 1024
#define SMMU_SIZE_PD (SMMU_NUM_PDE * 4)
#define SMMU_SIZE_PT (SMMU_NUM_PTE * 4)
#define SMMU_PDE_SHIFT 22
#define SMMU_PTE_SHIFT 12
#define SMMU_PAGE_MASK (~(SMMU_SIZE_PT-1))
#define SMMU_OFFSET_IN_PAGE(x) ((unsigned long)(x) & ~SMMU_PAGE_MASK)
#define SMMU_PFN_PHYS(x) ((phys_addr_t)(x) << SMMU_PTE_SHIFT)
#define SMMU_PHYS_PFN(x) ((unsigned long)((x) >> SMMU_PTE_SHIFT))
#define SMMU_PD_READABLE (1 << 31)
#define SMMU_PD_WRITABLE (1 << 30)
#define SMMU_PD_NONSECURE (1 << 29)
#define SMMU_PDE_READABLE (1 << 31)
#define SMMU_PDE_WRITABLE (1 << 30)
#define SMMU_PDE_NONSECURE (1 << 29)
#define SMMU_PDE_NEXT (1 << 28)
#define SMMU_PTE_READABLE (1 << 31)
#define SMMU_PTE_WRITABLE (1 << 30)
#define SMMU_PTE_NONSECURE (1 << 29)
#define SMMU_PDE_ATTR (SMMU_PDE_READABLE | SMMU_PDE_WRITABLE | \
SMMU_PDE_NONSECURE)
static unsigned int iova_pd_index(unsigned long iova)
{
return (iova >> SMMU_PDE_SHIFT) & (SMMU_NUM_PDE - 1);
}
static unsigned int iova_pt_index(unsigned long iova)
{
return (iova >> SMMU_PTE_SHIFT) & (SMMU_NUM_PTE - 1);
}
static bool smmu_dma_addr_valid(struct tegra_smmu *smmu, dma_addr_t addr)
{
addr >>= 12;
return (addr & smmu->pfn_mask) == addr;
}
static dma_addr_t smmu_pde_to_dma(struct tegra_smmu *smmu, u32 pde)
{
return (dma_addr_t)(pde & smmu->pfn_mask) << 12;
}
static void smmu_flush_ptc_all(struct tegra_smmu *smmu)
{
smmu_writel(smmu, SMMU_PTC_FLUSH_TYPE_ALL, SMMU_PTC_FLUSH);
}
static inline void smmu_flush_ptc(struct tegra_smmu *smmu, dma_addr_t dma,
unsigned long offset)
{
u32 value;
offset &= ~(smmu->mc->soc->atom_size - 1);
if (smmu->mc->soc->num_address_bits > 32) {
#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
value = (dma >> 32) & SMMU_PTC_FLUSH_HI_MASK;
#else
value = 0;
#endif
smmu_writel(smmu, value, SMMU_PTC_FLUSH_HI);
}
value = (dma + offset) | SMMU_PTC_FLUSH_TYPE_ADR;
smmu_writel(smmu, value, SMMU_PTC_FLUSH);
}
static inline void smmu_flush_tlb(struct tegra_smmu *smmu)
{
smmu_writel(smmu, SMMU_TLB_FLUSH_VA_MATCH_ALL, SMMU_TLB_FLUSH);
}
static inline void smmu_flush_tlb_asid(struct tegra_smmu *smmu,
unsigned long asid)
{
u32 value;
if (smmu->soc->num_asids == 4)
value = (asid & 0x3) << 29;
else
value = (asid & 0x7f) << 24;
value |= SMMU_TLB_FLUSH_ASID_MATCH | SMMU_TLB_FLUSH_VA_MATCH_ALL;
smmu_writel(smmu, value, SMMU_TLB_FLUSH);
}
static inline void smmu_flush_tlb_section(struct tegra_smmu *smmu,
unsigned long asid,
unsigned long iova)
{
u32 value;
if (smmu->soc->num_asids == 4)
value = (asid & 0x3) << 29;
else
value = (asid & 0x7f) << 24;
value |= SMMU_TLB_FLUSH_ASID_MATCH | SMMU_TLB_FLUSH_VA_SECTION(iova);
smmu_writel(smmu, value, SMMU_TLB_FLUSH);
}
static inline void smmu_flush_tlb_group(struct tegra_smmu *smmu,
unsigned long asid,
unsigned long iova)
{
u32 value;
if (smmu->soc->num_asids == 4)
value = (asid & 0x3) << 29;
else
value = (asid & 0x7f) << 24;
value |= SMMU_TLB_FLUSH_ASID_MATCH | SMMU_TLB_FLUSH_VA_GROUP(iova);
smmu_writel(smmu, value, SMMU_TLB_FLUSH);
}
static inline void smmu_flush(struct tegra_smmu *smmu)
{
smmu_readl(smmu, SMMU_PTB_ASID);
}
static int tegra_smmu_alloc_asid(struct tegra_smmu *smmu, unsigned int *idp)
{
unsigned long id;
id = find_first_zero_bit(smmu->asids, smmu->soc->num_asids);
if (id >= smmu->soc->num_asids)
return -ENOSPC;
set_bit(id, smmu->asids);
*idp = id;
return 0;
}
static void tegra_smmu_free_asid(struct tegra_smmu *smmu, unsigned int id)
{
clear_bit(id, smmu->asids);
}
static struct iommu_domain *tegra_smmu_domain_alloc_paging(struct device *dev)
{
struct tegra_smmu_as *as;
as = kzalloc(sizeof(*as), GFP_KERNEL);
if (!as)
return NULL;
as->attr = SMMU_PD_READABLE | SMMU_PD_WRITABLE | SMMU_PD_NONSECURE;
as->pd = alloc_page(GFP_KERNEL | __GFP_DMA | __GFP_ZERO);
if (!as->pd) {
kfree(as);
return NULL;
}
as->count = kcalloc(SMMU_NUM_PDE, sizeof(u32), GFP_KERNEL);
if (!as->count) {
__free_page(as->pd);
kfree(as);
return NULL;
}
as->pts = kcalloc(SMMU_NUM_PDE, sizeof(*as->pts), GFP_KERNEL);
if (!as->pts) {
kfree(as->count);
__free_page(as->pd);
kfree(as);
return NULL;
}
spin_lock_init(&as->lock);
/* setup aperture */
as->domain.geometry.aperture_start = 0;
as->domain.geometry.aperture_end = 0xffffffff;
as->domain.geometry.force_aperture = true;
return &as->domain;
}
static void tegra_smmu_domain_free(struct iommu_domain *domain)
{
struct tegra_smmu_as *as = to_smmu_as(domain);
/* TODO: free page directory and page tables */
WARN_ON_ONCE(as->use_count);
kfree(as->count);
kfree(as->pts);
kfree(as);
}
static const struct tegra_smmu_swgroup *
tegra_smmu_find_swgroup(struct tegra_smmu *smmu, unsigned int swgroup)
{
const struct tegra_smmu_swgroup *group = NULL;
unsigned int i;
for (i = 0; i < smmu->soc->num_swgroups; i++) {
if (smmu->soc->swgroups[i].swgroup == swgroup) {
group = &smmu->soc->swgroups[i];
break;
}
}
return group;
}
static void tegra_smmu_enable(struct tegra_smmu *smmu, unsigned int swgroup,
unsigned int asid)
{
const struct tegra_smmu_swgroup *group;
unsigned int i;
u32 value;
group = tegra_smmu_find_swgroup(smmu, swgroup);
if (group) {
value = smmu_readl(smmu, group->reg);
value &= ~SMMU_ASID_MASK;
value |= SMMU_ASID_VALUE(asid);
value |= SMMU_ASID_ENABLE;
smmu_writel(smmu, value, group->reg);
} else {
pr_warn("%s group from swgroup %u not found\n", __func__,
swgroup);
/* No point moving ahead if group was not found */
return;
}
for (i = 0; i < smmu->soc->num_clients; i++) {
const struct tegra_mc_client *client = &smmu->soc->clients[i];
if (client->swgroup != swgroup)
continue;
value = smmu_readl(smmu, client->regs.smmu.reg);
value |= BIT(client->regs.smmu.bit);
smmu_writel(smmu, value, client->regs.smmu.reg);
}
}
static void tegra_smmu_disable(struct tegra_smmu *smmu, unsigned int swgroup,
unsigned int asid)
{
const struct tegra_smmu_swgroup *group;
unsigned int i;
u32 value;
group = tegra_smmu_find_swgroup(smmu, swgroup);
if (group) {
value = smmu_readl(smmu, group->reg);
value &= ~SMMU_ASID_MASK;
value |= SMMU_ASID_VALUE(asid);
value &= ~SMMU_ASID_ENABLE;
smmu_writel(smmu, value, group->reg);
}
for (i = 0; i < smmu->soc->num_clients; i++) {
const struct tegra_mc_client *client = &smmu->soc->clients[i];
if (client->swgroup != swgroup)
continue;
value = smmu_readl(smmu, client->regs.smmu.reg);
value &= ~BIT(client->regs.smmu.bit);
smmu_writel(smmu, value, client->regs.smmu.reg);
}
}
static int tegra_smmu_as_prepare(struct tegra_smmu *smmu,
struct tegra_smmu_as *as)
{
u32 value;
int err = 0;
mutex_lock(&smmu->lock);
if (as->use_count > 0) {
as->use_count++;
goto unlock;
}
as->pd_dma = dma_map_page(smmu->dev, as->pd, 0, SMMU_SIZE_PD,
DMA_TO_DEVICE);
if (dma_mapping_error(smmu->dev, as->pd_dma)) {
err = -ENOMEM;
goto unlock;
}
/* We can't handle 64-bit DMA addresses */
if (!smmu_dma_addr_valid(smmu, as->pd_dma)) {
err = -ENOMEM;
goto err_unmap;
}
err = tegra_smmu_alloc_asid(smmu, &as->id);
if (err < 0)
goto err_unmap;
smmu_flush_ptc(smmu, as->pd_dma, 0);
smmu_flush_tlb_asid(smmu, as->id);
smmu_writel(smmu, as->id & 0x7f, SMMU_PTB_ASID);
value = SMMU_PTB_DATA_VALUE(as->pd_dma, as->attr);
smmu_writel(smmu, value, SMMU_PTB_DATA);
smmu_flush(smmu);
as->smmu = smmu;
as->use_count++;
mutex_unlock(&smmu->lock);
return 0;
err_unmap:
dma_unmap_page(smmu->dev, as->pd_dma, SMMU_SIZE_PD, DMA_TO_DEVICE);
unlock:
mutex_unlock(&smmu->lock);
return err;
}
static void tegra_smmu_as_unprepare(struct tegra_smmu *smmu,
struct tegra_smmu_as *as)
{
mutex_lock(&smmu->lock);
if (--as->use_count > 0) {
mutex_unlock(&smmu->lock);
return;
}
tegra_smmu_free_asid(smmu, as->id);
dma_unmap_page(smmu->dev, as->pd_dma, SMMU_SIZE_PD, DMA_TO_DEVICE);
as->smmu = NULL;
mutex_unlock(&smmu->lock);
}
static int tegra_smmu_attach_dev(struct iommu_domain *domain,
struct device *dev)
{
struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
struct tegra_smmu *smmu = dev_iommu_priv_get(dev);
struct tegra_smmu_as *as = to_smmu_as(domain);
unsigned int index;
int err;
if (!fwspec)
return -ENOENT;
for (index = 0; index < fwspec->num_ids; index++) {
err = tegra_smmu_as_prepare(smmu, as);
if (err)
goto disable;
tegra_smmu_enable(smmu, fwspec->ids[index], as->id);
}
if (index == 0)
return -ENODEV;
return 0;
disable:
while (index--) {
tegra_smmu_disable(smmu, fwspec->ids[index], as->id);
tegra_smmu_as_unprepare(smmu, as);
}
return err;
}
static int tegra_smmu_identity_attach(struct iommu_domain *identity_domain,
struct device *dev)
{
struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
struct tegra_smmu_as *as;
struct tegra_smmu *smmu;
unsigned int index;
if (!fwspec)
return -ENODEV;
if (domain == identity_domain || !domain)
return 0;
as = to_smmu_as(domain);
smmu = as->smmu;
for (index = 0; index < fwspec->num_ids; index++) {
tegra_smmu_disable(smmu, fwspec->ids[index], as->id);
tegra_smmu_as_unprepare(smmu, as);
}
return 0;
}
static struct iommu_domain_ops tegra_smmu_identity_ops = {
.attach_dev = tegra_smmu_identity_attach,
};
static struct iommu_domain tegra_smmu_identity_domain = {
.type = IOMMU_DOMAIN_IDENTITY,
.ops = &tegra_smmu_identity_ops,
};
static void tegra_smmu_set_pde(struct tegra_smmu_as *as, unsigned long iova,
u32 value)
{
unsigned int pd_index = iova_pd_index(iova);
struct tegra_smmu *smmu = as->smmu;
u32 *pd = page_address(as->pd);
unsigned long offset = pd_index * sizeof(*pd);
/* Set the page directory entry first */
pd[pd_index] = value;
/* The flush the page directory entry from caches */
dma_sync_single_range_for_device(smmu->dev, as->pd_dma, offset,
sizeof(*pd), DMA_TO_DEVICE);
/* And flush the iommu */
smmu_flush_ptc(smmu, as->pd_dma, offset);
smmu_flush_tlb_section(smmu, as->id, iova);
smmu_flush(smmu);
}
static u32 *tegra_smmu_pte_offset(struct page *pt_page, unsigned long iova)
{
u32 *pt = page_address(pt_page);
return pt + iova_pt_index(iova);
}
static u32 *tegra_smmu_pte_lookup(struct tegra_smmu_as *as, unsigned long iova,
dma_addr_t *dmap)
{
unsigned int pd_index = iova_pd_index(iova);
struct tegra_smmu *smmu = as->smmu;
struct page *pt_page;
u32 *pd;
pt_page = as->pts[pd_index];
if (!pt_page)
return NULL;
pd = page_address(as->pd);
*dmap = smmu_pde_to_dma(smmu, pd[pd_index]);
return tegra_smmu_pte_offset(pt_page, iova);
}
static u32 *as_get_pte(struct tegra_smmu_as *as, dma_addr_t iova,
dma_addr_t *dmap, struct page *page)
{
unsigned int pde = iova_pd_index(iova);
struct tegra_smmu *smmu = as->smmu;
if (!as->pts[pde]) {
dma_addr_t dma;
dma = dma_map_page(smmu->dev, page, 0, SMMU_SIZE_PT,
DMA_TO_DEVICE);
if (dma_mapping_error(smmu->dev, dma)) {
__free_page(page);
return NULL;
}
if (!smmu_dma_addr_valid(smmu, dma)) {
dma_unmap_page(smmu->dev, dma, SMMU_SIZE_PT,
DMA_TO_DEVICE);
__free_page(page);
return NULL;
}
as->pts[pde] = page;
tegra_smmu_set_pde(as, iova, SMMU_MK_PDE(dma, SMMU_PDE_ATTR |
SMMU_PDE_NEXT));
*dmap = dma;
} else {
u32 *pd = page_address(as->pd);
*dmap = smmu_pde_to_dma(smmu, pd[pde]);
}
return tegra_smmu_pte_offset(as->pts[pde], iova);
}
static void tegra_smmu_pte_get_use(struct tegra_smmu_as *as, unsigned long iova)
{
unsigned int pd_index = iova_pd_index(iova);
as->count[pd_index]++;
}
static void tegra_smmu_pte_put_use(struct tegra_smmu_as *as, unsigned long iova)
{
unsigned int pde = iova_pd_index(iova);
struct page *page = as->pts[pde];
/*
* When no entries in this page table are used anymore, return the
* memory page to the system.
*/
if (--as->count[pde] == 0) {
struct tegra_smmu *smmu = as->smmu;
u32 *pd = page_address(as->pd);
dma_addr_t pte_dma = smmu_pde_to_dma(smmu, pd[pde]);
tegra_smmu_set_pde(as, iova, 0);
dma_unmap_page(smmu->dev, pte_dma, SMMU_SIZE_PT, DMA_TO_DEVICE);
__free_page(page);
as->pts[pde] = NULL;
}
}
static void tegra_smmu_set_pte(struct tegra_smmu_as *as, unsigned long iova,
u32 *pte, dma_addr_t pte_dma, u32 val)
{
struct tegra_smmu *smmu = as->smmu;
unsigned long offset = SMMU_OFFSET_IN_PAGE(pte);
*pte = val;
dma_sync_single_range_for_device(smmu->dev, pte_dma, offset,
4, DMA_TO_DEVICE);
smmu_flush_ptc(smmu, pte_dma, offset);
smmu_flush_tlb_group(smmu, as->id, iova);
smmu_flush(smmu);
}
static struct page *as_get_pde_page(struct tegra_smmu_as *as,
unsigned long iova, gfp_t gfp,
unsigned long *flags)
{
unsigned int pde = iova_pd_index(iova);
struct page *page = as->pts[pde];
/* at first check whether allocation needs to be done at all */
if (page)
return page;
/*
* In order to prevent exhaustion of the atomic memory pool, we
* allocate page in a sleeping context if GFP flags permit. Hence
* spinlock needs to be unlocked and re-locked after allocation.
*/
if (gfpflags_allow_blocking(gfp))
spin_unlock_irqrestore(&as->lock, *flags);
page = alloc_page(gfp | __GFP_DMA | __GFP_ZERO);
if (gfpflags_allow_blocking(gfp))
spin_lock_irqsave(&as->lock, *flags);
/*
* In a case of blocking allocation, a concurrent mapping may win
* the PDE allocation. In this case the allocated page isn't needed
* if allocation succeeded and the allocation failure isn't fatal.
*/
if (as->pts[pde]) {
if (page)
__free_page(page);
page = as->pts[pde];
}
return page;
}
static int
__tegra_smmu_map(struct iommu_domain *domain, unsigned long iova,
phys_addr_t paddr, size_t size, int prot, gfp_t gfp,
unsigned long *flags)
{
struct tegra_smmu_as *as = to_smmu_as(domain);
dma_addr_t pte_dma;
struct page *page;
u32 pte_attrs;
u32 *pte;
page = as_get_pde_page(as, iova, gfp, flags);
if (!page)
return -ENOMEM;
pte = as_get_pte(as, iova, &pte_dma, page);
if (!pte)
return -ENOMEM;
/* If we aren't overwriting a pre-existing entry, increment use */
if (*pte == 0)
tegra_smmu_pte_get_use(as, iova);
pte_attrs = SMMU_PTE_NONSECURE;
if (prot & IOMMU_READ)
pte_attrs |= SMMU_PTE_READABLE;
if (prot & IOMMU_WRITE)
pte_attrs |= SMMU_PTE_WRITABLE;
tegra_smmu_set_pte(as, iova, pte, pte_dma,
SMMU_PHYS_PFN(paddr) | pte_attrs);
return 0;
}
static size_t
__tegra_smmu_unmap(struct iommu_domain *domain, unsigned long iova,
size_t size, struct iommu_iotlb_gather *gather)
{
struct tegra_smmu_as *as = to_smmu_as(domain);
dma_addr_t pte_dma;
u32 *pte;
pte = tegra_smmu_pte_lookup(as, iova, &pte_dma);
if (!pte || !*pte)
return 0;
tegra_smmu_set_pte(as, iova, pte, pte_dma, 0);
tegra_smmu_pte_put_use(as, iova);
return size;
}
static int tegra_smmu_map(struct iommu_domain *domain, unsigned long iova,
phys_addr_t paddr, size_t size, size_t count,
int prot, gfp_t gfp, size_t *mapped)
{
struct tegra_smmu_as *as = to_smmu_as(domain);
unsigned long flags;
int ret;
spin_lock_irqsave(&as->lock, flags);
ret = __tegra_smmu_map(domain, iova, paddr, size, prot, gfp, &flags);
spin_unlock_irqrestore(&as->lock, flags);
if (!ret)
*mapped = size;
return ret;
}
static size_t tegra_smmu_unmap(struct iommu_domain *domain, unsigned long iova,
size_t size, size_t count, struct iommu_iotlb_gather *gather)
{
struct tegra_smmu_as *as = to_smmu_as(domain);
unsigned long flags;
spin_lock_irqsave(&as->lock, flags);
size = __tegra_smmu_unmap(domain, iova, size, gather);
spin_unlock_irqrestore(&as->lock, flags);
return size;
}
static phys_addr_t tegra_smmu_iova_to_phys(struct iommu_domain *domain,
dma_addr_t iova)
{
struct tegra_smmu_as *as = to_smmu_as(domain);
unsigned long pfn;
dma_addr_t pte_dma;
u32 *pte;
pte = tegra_smmu_pte_lookup(as, iova, &pte_dma);
if (!pte || !*pte)
return 0;
pfn = *pte & as->smmu->pfn_mask;
return SMMU_PFN_PHYS(pfn) + SMMU_OFFSET_IN_PAGE(iova);
}
static struct tegra_smmu *tegra_smmu_find(struct device_node *np)
{
struct platform_device *pdev;
struct tegra_mc *mc;
pdev = of_find_device_by_node(np);
if (!pdev)
return NULL;
mc = platform_get_drvdata(pdev);
if (!mc) {
put_device(&pdev->dev);
return NULL;
}
return mc->smmu;
}
static int tegra_smmu_configure(struct tegra_smmu *smmu, struct device *dev,
struct of_phandle_args *args)
{
const struct iommu_ops *ops = smmu->iommu.ops;
int err;
err = iommu_fwspec_init(dev, &dev->of_node->fwnode, ops);
if (err < 0) {
dev_err(dev, "failed to initialize fwspec: %d\n", err);
return err;
}
err = ops->of_xlate(dev, args);
if (err < 0) {
dev_err(dev, "failed to parse SW group ID: %d\n", err);
iommu_fwspec_free(dev);
return err;
}
return 0;
}
static struct iommu_device *tegra_smmu_probe_device(struct device *dev)
{
struct device_node *np = dev->of_node;
struct tegra_smmu *smmu = NULL;
struct of_phandle_args args;
unsigned int index = 0;
int err;
while (of_parse_phandle_with_args(np, "iommus", "#iommu-cells", index,
&args) == 0) {
smmu = tegra_smmu_find(args.np);
if (smmu) {
err = tegra_smmu_configure(smmu, dev, &args);
if (err < 0) {
of_node_put(args.np);
return ERR_PTR(err);
}
}
of_node_put(args.np);
index++;
}
smmu = dev_iommu_priv_get(dev);
if (!smmu)
return ERR_PTR(-ENODEV);
return &smmu->iommu;
}
static const struct tegra_smmu_group_soc *
tegra_smmu_find_group(struct tegra_smmu *smmu, unsigned int swgroup)
{
unsigned int i, j;
for (i = 0; i < smmu->soc->num_groups; i++)
for (j = 0; j < smmu->soc->groups[i].num_swgroups; j++)
if (smmu->soc->groups[i].swgroups[j] == swgroup)
return &smmu->soc->groups[i];
return NULL;
}
static void tegra_smmu_group_release(void *iommu_data)
{
struct tegra_smmu_group *group = iommu_data;
struct tegra_smmu *smmu = group->smmu;
mutex_lock(&smmu->lock);
list_del(&group->list);
mutex_unlock(&smmu->lock);
}
static struct iommu_group *tegra_smmu_device_group(struct device *dev)
{
struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
struct tegra_smmu *smmu = dev_iommu_priv_get(dev);
const struct tegra_smmu_group_soc *soc;
unsigned int swgroup = fwspec->ids[0];
struct tegra_smmu_group *group;
struct iommu_group *grp;
/* Find group_soc associating with swgroup */
soc = tegra_smmu_find_group(smmu, swgroup);
mutex_lock(&smmu->lock);
/* Find existing iommu_group associating with swgroup or group_soc */
list_for_each_entry(group, &smmu->groups, list)
if ((group->swgroup == swgroup) || (soc && group->soc == soc)) {
grp = iommu_group_ref_get(group->group);
mutex_unlock(&smmu->lock);
return grp;
}
group = devm_kzalloc(smmu->dev, sizeof(*group), GFP_KERNEL);
if (!group) {
mutex_unlock(&smmu->lock);
return NULL;
}
INIT_LIST_HEAD(&group->list);
group->swgroup = swgroup;
group->smmu = smmu;
group->soc = soc;
if (dev_is_pci(dev))
group->group = pci_device_group(dev);
else
group->group = generic_device_group(dev);
if (IS_ERR(group->group)) {
devm_kfree(smmu->dev, group);
mutex_unlock(&smmu->lock);
return NULL;
}
iommu_group_set_iommudata(group->group, group, tegra_smmu_group_release);
if (soc)
iommu_group_set_name(group->group, soc->name);
list_add_tail(&group->list, &smmu->groups);
mutex_unlock(&smmu->lock);
return group->group;
}
static int tegra_smmu_of_xlate(struct device *dev,
struct of_phandle_args *args)
{
struct platform_device *iommu_pdev = of_find_device_by_node(args->np);
struct tegra_mc *mc = platform_get_drvdata(iommu_pdev);
u32 id = args->args[0];
/*
* Note: we are here releasing the reference of &iommu_pdev->dev, which
* is mc->dev. Although some functions in tegra_smmu_ops may keep using
* its private data beyond this point, it's still safe to do so because
* the SMMU parent device is the same as the MC, so the reference count
* isn't strictly necessary.
*/
put_device(&iommu_pdev->dev);
dev_iommu_priv_set(dev, mc->smmu);
return iommu_fwspec_add_ids(dev, &id, 1);
}
static int tegra_smmu_def_domain_type(struct device *dev)
{
/*
* FIXME: For now we want to run all translation in IDENTITY mode, due
* to some device quirks. Better would be to just quirk the troubled
* devices.
*/
return IOMMU_DOMAIN_IDENTITY;
}
static const struct iommu_ops tegra_smmu_ops = {
.identity_domain = &tegra_smmu_identity_domain,
.def_domain_type = &tegra_smmu_def_domain_type,
.domain_alloc_paging = tegra_smmu_domain_alloc_paging,
.probe_device = tegra_smmu_probe_device,
.device_group = tegra_smmu_device_group,
.of_xlate = tegra_smmu_of_xlate,
.pgsize_bitmap = SZ_4K,
.default_domain_ops = &(const struct iommu_domain_ops) {
.attach_dev = tegra_smmu_attach_dev,
.map_pages = tegra_smmu_map,
.unmap_pages = tegra_smmu_unmap,
.iova_to_phys = tegra_smmu_iova_to_phys,
.free = tegra_smmu_domain_free,
}
};
static void tegra_smmu_ahb_enable(void)
{
static const struct of_device_id ahb_match[] = {
{ .compatible = "nvidia,tegra30-ahb", },
{ }
};
struct device_node *ahb;
ahb = of_find_matching_node(NULL, ahb_match);
if (ahb) {
tegra_ahb_enable_smmu(ahb);
of_node_put(ahb);
}
}
static int tegra_smmu_swgroups_show(struct seq_file *s, void *data)
{
struct tegra_smmu *smmu = s->private;
unsigned int i;
u32 value;
seq_printf(s, "swgroup enabled ASID\n");
seq_printf(s, "------------------------\n");
for (i = 0; i < smmu->soc->num_swgroups; i++) {
const struct tegra_smmu_swgroup *group = &smmu->soc->swgroups[i];
const char *status;
unsigned int asid;
value = smmu_readl(smmu, group->reg);
if (value & SMMU_ASID_ENABLE)
status = "yes";
else
status = "no";
asid = value & SMMU_ASID_MASK;
seq_printf(s, "%-9s %-7s %#04x\n", group->name, status,
asid);
}
return 0;
}
DEFINE_SHOW_ATTRIBUTE(tegra_smmu_swgroups);
static int tegra_smmu_clients_show(struct seq_file *s, void *data)
{
struct tegra_smmu *smmu = s->private;
unsigned int i;
u32 value;
seq_printf(s, "client enabled\n");
seq_printf(s, "--------------------\n");
for (i = 0; i < smmu->soc->num_clients; i++) {
const struct tegra_mc_client *client = &smmu->soc->clients[i];
const char *status;
value = smmu_readl(smmu, client->regs.smmu.reg);
if (value & BIT(client->regs.smmu.bit))
status = "yes";
else
status = "no";
seq_printf(s, "%-12s %s\n", client->name, status);
}
return 0;
}
DEFINE_SHOW_ATTRIBUTE(tegra_smmu_clients);
static void tegra_smmu_debugfs_init(struct tegra_smmu *smmu)
{
smmu->debugfs = debugfs_create_dir("smmu", NULL);
debugfs_create_file("swgroups", S_IRUGO, smmu->debugfs, smmu,
&tegra_smmu_swgroups_fops);
debugfs_create_file("clients", S_IRUGO, smmu->debugfs, smmu,
&tegra_smmu_clients_fops);
}
static void tegra_smmu_debugfs_exit(struct tegra_smmu *smmu)
{
debugfs_remove_recursive(smmu->debugfs);
}
struct tegra_smmu *tegra_smmu_probe(struct device *dev,
const struct tegra_smmu_soc *soc,
struct tegra_mc *mc)
{
struct tegra_smmu *smmu;
u32 value;
int err;
smmu = devm_kzalloc(dev, sizeof(*smmu), GFP_KERNEL);
if (!smmu)
return ERR_PTR(-ENOMEM);
/*
* This is a bit of a hack. Ideally we'd want to simply return this
* value. However iommu_device_register() will attempt to add
* all devices to the IOMMU before we get that far. In order
* not to rely on global variables to track the IOMMU instance, we
* set it here so that it can be looked up from the .probe_device()
* callback via the IOMMU device's .drvdata field.
*/
mc->smmu = smmu;
smmu->asids = devm_bitmap_zalloc(dev, soc->num_asids, GFP_KERNEL);
if (!smmu->asids)
return ERR_PTR(-ENOMEM);
INIT_LIST_HEAD(&smmu->groups);
mutex_init(&smmu->lock);
smmu->regs = mc->regs;
smmu->soc = soc;
smmu->dev = dev;
smmu->mc = mc;
smmu->pfn_mask =
BIT_MASK(mc->soc->num_address_bits - SMMU_PTE_SHIFT) - 1;
dev_dbg(dev, "address bits: %u, PFN mask: %#lx\n",
mc->soc->num_address_bits, smmu->pfn_mask);
smmu->tlb_mask = (1 << fls(smmu->soc->num_tlb_lines)) - 1;
dev_dbg(dev, "TLB lines: %u, mask: %#lx\n", smmu->soc->num_tlb_lines,
smmu->tlb_mask);
value = SMMU_PTC_CONFIG_ENABLE | SMMU_PTC_CONFIG_INDEX_MAP(0x3f);
if (soc->supports_request_limit)
value |= SMMU_PTC_CONFIG_REQ_LIMIT(8);
smmu_writel(smmu, value, SMMU_PTC_CONFIG);
value = SMMU_TLB_CONFIG_HIT_UNDER_MISS |
SMMU_TLB_CONFIG_ACTIVE_LINES(smmu);
if (soc->supports_round_robin_arbitration)
value |= SMMU_TLB_CONFIG_ROUND_ROBIN_ARBITRATION;
smmu_writel(smmu, value, SMMU_TLB_CONFIG);
smmu_flush_ptc_all(smmu);
smmu_flush_tlb(smmu);
smmu_writel(smmu, SMMU_CONFIG_ENABLE, SMMU_CONFIG);
smmu_flush(smmu);
tegra_smmu_ahb_enable();
err = iommu_device_sysfs_add(&smmu->iommu, dev, NULL, dev_name(dev));
if (err)
return ERR_PTR(err);
err = iommu_device_register(&smmu->iommu, &tegra_smmu_ops, dev);
if (err) {
iommu_device_sysfs_remove(&smmu->iommu);
return ERR_PTR(err);
}
if (IS_ENABLED(CONFIG_DEBUG_FS))
tegra_smmu_debugfs_init(smmu);
return smmu;
}
void tegra_smmu_remove(struct tegra_smmu *smmu)
{
iommu_device_unregister(&smmu->iommu);
iommu_device_sysfs_remove(&smmu->iommu);
if (IS_ENABLED(CONFIG_DEBUG_FS))
tegra_smmu_debugfs_exit(smmu);
}