blob: 720829724d8619e334577ed780313e813dee3f36 [file] [log] [blame]
/*
* Copyright (C) 2011-2014 NVIDIA CORPORATION. All rights reserved.
*
* 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.
*/
#include <linux/err.h>
#include <linux/iommu.h>
#include <linux/kernel.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <soc/tegra/ahb.h>
#include <soc/tegra/mc.h>
struct tegra_smmu {
void __iomem *regs;
struct device *dev;
struct tegra_mc *mc;
const struct tegra_smmu_soc *soc;
unsigned long *asids;
struct mutex lock;
struct list_head list;
};
struct tegra_smmu_as {
struct iommu_domain domain;
struct tegra_smmu *smmu;
unsigned int use_count;
struct page *count;
struct page *pd;
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(x) ((x) & 0x3f)
#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(page, attr) (page_to_phys(page) >> 12 | (attr))
#define SMMU_MK_PDE(page, attr) (page_to_phys(page) >> 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_ASID(x) (((x) & 0x7f) << 24)
#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_PFN_MASK 0x000fffff
#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)
#define SMMU_PTE_ATTR (SMMU_PTE_READABLE | SMMU_PTE_WRITABLE | \
SMMU_PTE_NONSECURE)
static inline void smmu_flush_ptc(struct tegra_smmu *smmu, struct page *page,
unsigned long offset)
{
phys_addr_t phys = page ? page_to_phys(page) : 0;
u32 value;
if (page) {
offset &= ~(smmu->mc->soc->atom_size - 1);
if (smmu->mc->soc->num_address_bits > 32) {
#ifdef CONFIG_PHYS_ADDR_T_64BIT
value = (phys >> 32) & SMMU_PTC_FLUSH_HI_MASK;
#else
value = 0;
#endif
smmu_writel(smmu, value, SMMU_PTC_FLUSH_HI);
}
value = (phys + offset) | SMMU_PTC_FLUSH_TYPE_ADR;
} else {
value = SMMU_PTC_FLUSH_TYPE_ALL;
}
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;
value = SMMU_TLB_FLUSH_ASID_MATCH | SMMU_TLB_FLUSH_ASID(asid) |
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;
value = SMMU_TLB_FLUSH_ASID_MATCH | SMMU_TLB_FLUSH_ASID(asid) |
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;
value = SMMU_TLB_FLUSH_ASID_MATCH | SMMU_TLB_FLUSH_ASID(asid) |
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_CONFIG);
}
static int tegra_smmu_alloc_asid(struct tegra_smmu *smmu, unsigned int *idp)
{
unsigned long id;
mutex_lock(&smmu->lock);
id = find_first_zero_bit(smmu->asids, smmu->soc->num_asids);
if (id >= smmu->soc->num_asids) {
mutex_unlock(&smmu->lock);
return -ENOSPC;
}
set_bit(id, smmu->asids);
*idp = id;
mutex_unlock(&smmu->lock);
return 0;
}
static void tegra_smmu_free_asid(struct tegra_smmu *smmu, unsigned int id)
{
mutex_lock(&smmu->lock);
clear_bit(id, smmu->asids);
mutex_unlock(&smmu->lock);
}
static bool tegra_smmu_capable(enum iommu_cap cap)
{
return false;
}
static struct iommu_domain *tegra_smmu_domain_alloc(unsigned type)
{
struct tegra_smmu_as *as;
unsigned int i;
uint32_t *pd;
if (type != IOMMU_DOMAIN_UNMANAGED)
return NULL;
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);
if (!as->pd) {
kfree(as);
return NULL;
}
as->count = alloc_page(GFP_KERNEL);
if (!as->count) {
__free_page(as->pd);
kfree(as);
return NULL;
}
/* clear PDEs */
pd = page_address(as->pd);
SetPageReserved(as->pd);
for (i = 0; i < SMMU_NUM_PDE; i++)
pd[i] = 0;
/* clear PDE usage counters */
pd = page_address(as->count);
SetPageReserved(as->count);
for (i = 0; i < SMMU_NUM_PDE; i++)
pd[i] = 0;
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 */
ClearPageReserved(as->pd);
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;
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->smmu.reg);
value |= BIT(client->smmu.bit);
smmu_writel(smmu, value, client->smmu.reg);
}
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);
}
}
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->smmu.reg);
value &= ~BIT(client->smmu.bit);
smmu_writel(smmu, value, client->smmu.reg);
}
}
static int tegra_smmu_as_prepare(struct tegra_smmu *smmu,
struct tegra_smmu_as *as)
{
u32 value;
int err;
if (as->use_count > 0) {
as->use_count++;
return 0;
}
err = tegra_smmu_alloc_asid(smmu, &as->id);
if (err < 0)
return err;
smmu->soc->ops->flush_dcache(as->pd, 0, SMMU_SIZE_PD);
smmu_flush_ptc(smmu, as->pd, 0);
smmu_flush_tlb_asid(smmu, as->id);
smmu_writel(smmu, as->id & 0x7f, SMMU_PTB_ASID);
value = SMMU_PTB_DATA_VALUE(as->pd, as->attr);
smmu_writel(smmu, value, SMMU_PTB_DATA);
smmu_flush(smmu);
as->smmu = smmu;
as->use_count++;
return 0;
}
static void tegra_smmu_as_unprepare(struct tegra_smmu *smmu,
struct tegra_smmu_as *as)
{
if (--as->use_count > 0)
return;
tegra_smmu_free_asid(smmu, as->id);
as->smmu = NULL;
}
static int tegra_smmu_attach_dev(struct iommu_domain *domain,
struct device *dev)
{
struct tegra_smmu *smmu = dev->archdata.iommu;
struct tegra_smmu_as *as = to_smmu_as(domain);
struct device_node *np = dev->of_node;
struct of_phandle_args args;
unsigned int index = 0;
int err = 0;
while (!of_parse_phandle_with_args(np, "iommus", "#iommu-cells", index,
&args)) {
unsigned int swgroup = args.args[0];
if (args.np != smmu->dev->of_node) {
of_node_put(args.np);
continue;
}
of_node_put(args.np);
err = tegra_smmu_as_prepare(smmu, as);
if (err < 0)
return err;
tegra_smmu_enable(smmu, swgroup, as->id);
index++;
}
if (index == 0)
return -ENODEV;
return 0;
}
static void tegra_smmu_detach_dev(struct iommu_domain *domain, struct device *dev)
{
struct tegra_smmu_as *as = to_smmu_as(domain);
struct device_node *np = dev->of_node;
struct tegra_smmu *smmu = as->smmu;
struct of_phandle_args args;
unsigned int index = 0;
while (!of_parse_phandle_with_args(np, "iommus", "#iommu-cells", index,
&args)) {
unsigned int swgroup = args.args[0];
if (args.np != smmu->dev->of_node) {
of_node_put(args.np);
continue;
}
of_node_put(args.np);
tegra_smmu_disable(smmu, swgroup, as->id);
tegra_smmu_as_unprepare(smmu, as);
index++;
}
}
static u32 *as_get_pte(struct tegra_smmu_as *as, dma_addr_t iova,
struct page **pagep)
{
u32 *pd = page_address(as->pd), *pt, *count;
u32 pde = (iova >> SMMU_PDE_SHIFT) & 0x3ff;
u32 pte = (iova >> SMMU_PTE_SHIFT) & 0x3ff;
struct tegra_smmu *smmu = as->smmu;
struct page *page;
unsigned int i;
if (pd[pde] == 0) {
page = alloc_page(GFP_KERNEL | __GFP_DMA);
if (!page)
return NULL;
pt = page_address(page);
SetPageReserved(page);
for (i = 0; i < SMMU_NUM_PTE; i++)
pt[i] = 0;
smmu->soc->ops->flush_dcache(page, 0, SMMU_SIZE_PT);
pd[pde] = SMMU_MK_PDE(page, SMMU_PDE_ATTR | SMMU_PDE_NEXT);
smmu->soc->ops->flush_dcache(as->pd, pde << 2, 4);
smmu_flush_ptc(smmu, as->pd, pde << 2);
smmu_flush_tlb_section(smmu, as->id, iova);
smmu_flush(smmu);
} else {
page = pfn_to_page(pd[pde] & SMMU_PFN_MASK);
pt = page_address(page);
}
*pagep = page;
/* Keep track of entries in this page table. */
count = page_address(as->count);
if (pt[pte] == 0)
count[pde]++;
return &pt[pte];
}
static void as_put_pte(struct tegra_smmu_as *as, dma_addr_t iova)
{
u32 pde = (iova >> SMMU_PDE_SHIFT) & 0x3ff;
u32 pte = (iova >> SMMU_PTE_SHIFT) & 0x3ff;
u32 *count = page_address(as->count);
u32 *pd = page_address(as->pd), *pt;
struct page *page;
page = pfn_to_page(pd[pde] & SMMU_PFN_MASK);
pt = page_address(page);
/*
* When no entries in this page table are used anymore, return the
* memory page to the system.
*/
if (pt[pte] != 0) {
if (--count[pde] == 0) {
ClearPageReserved(page);
__free_page(page);
pd[pde] = 0;
}
pt[pte] = 0;
}
}
static int tegra_smmu_map(struct iommu_domain *domain, unsigned long iova,
phys_addr_t paddr, size_t size, int prot)
{
struct tegra_smmu_as *as = to_smmu_as(domain);
struct tegra_smmu *smmu = as->smmu;
unsigned long offset;
struct page *page;
u32 *pte;
pte = as_get_pte(as, iova, &page);
if (!pte)
return -ENOMEM;
*pte = __phys_to_pfn(paddr) | SMMU_PTE_ATTR;
offset = offset_in_page(pte);
smmu->soc->ops->flush_dcache(page, offset, 4);
smmu_flush_ptc(smmu, page, offset);
smmu_flush_tlb_group(smmu, as->id, iova);
smmu_flush(smmu);
return 0;
}
static size_t tegra_smmu_unmap(struct iommu_domain *domain, unsigned long iova,
size_t size)
{
struct tegra_smmu_as *as = to_smmu_as(domain);
struct tegra_smmu *smmu = as->smmu;
unsigned long offset;
struct page *page;
u32 *pte;
pte = as_get_pte(as, iova, &page);
if (!pte)
return 0;
offset = offset_in_page(pte);
as_put_pte(as, iova);
smmu->soc->ops->flush_dcache(page, offset, 4);
smmu_flush_ptc(smmu, page, offset);
smmu_flush_tlb_group(smmu, as->id, iova);
smmu_flush(smmu);
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);
struct page *page;
unsigned long pfn;
u32 *pte;
pte = as_get_pte(as, iova, &page);
pfn = *pte & SMMU_PFN_MASK;
return PFN_PHYS(pfn);
}
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)
return NULL;
return mc->smmu;
}
static int tegra_smmu_add_device(struct device *dev)
{
struct device_node *np = dev->of_node;
struct of_phandle_args args;
unsigned int index = 0;
while (of_parse_phandle_with_args(np, "iommus", "#iommu-cells", index,
&args) == 0) {
struct tegra_smmu *smmu;
smmu = tegra_smmu_find(args.np);
if (smmu) {
/*
* Only a single IOMMU master interface is currently
* supported by the Linux kernel, so abort after the
* first match.
*/
dev->archdata.iommu = smmu;
break;
}
index++;
}
return 0;
}
static void tegra_smmu_remove_device(struct device *dev)
{
dev->archdata.iommu = NULL;
}
static const struct iommu_ops tegra_smmu_ops = {
.capable = tegra_smmu_capable,
.domain_alloc = tegra_smmu_domain_alloc,
.domain_free = tegra_smmu_domain_free,
.attach_dev = tegra_smmu_attach_dev,
.detach_dev = tegra_smmu_detach_dev,
.add_device = tegra_smmu_add_device,
.remove_device = tegra_smmu_remove_device,
.map = tegra_smmu_map,
.unmap = tegra_smmu_unmap,
.map_sg = default_iommu_map_sg,
.iova_to_phys = tegra_smmu_iova_to_phys,
.pgsize_bitmap = SZ_4K,
};
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);
}
}
struct tegra_smmu *tegra_smmu_probe(struct device *dev,
const struct tegra_smmu_soc *soc,
struct tegra_mc *mc)
{
struct tegra_smmu *smmu;
size_t size;
u32 value;
int err;
/* This can happen on Tegra20 which doesn't have an SMMU */
if (!soc)
return NULL;
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 the IOMMU registration process will attempt to add
* all devices to the IOMMU when bus_set_iommu() is called. 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 .add_device()
* callback via the IOMMU device's .drvdata field.
*/
mc->smmu = smmu;
size = BITS_TO_LONGS(soc->num_asids) * sizeof(long);
smmu->asids = devm_kzalloc(dev, size, GFP_KERNEL);
if (!smmu->asids)
return ERR_PTR(-ENOMEM);
mutex_init(&smmu->lock);
smmu->regs = mc->regs;
smmu->soc = soc;
smmu->dev = dev;
smmu->mc = mc;
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(0x20);
if (soc->supports_round_robin_arbitration)
value |= SMMU_TLB_CONFIG_ROUND_ROBIN_ARBITRATION;
smmu_writel(smmu, value, SMMU_TLB_CONFIG);
smmu_flush_ptc(smmu, NULL, 0);
smmu_flush_tlb(smmu);
smmu_writel(smmu, SMMU_CONFIG_ENABLE, SMMU_CONFIG);
smmu_flush(smmu);
tegra_smmu_ahb_enable();
err = bus_set_iommu(&platform_bus_type, &tegra_smmu_ops);
if (err < 0)
return ERR_PTR(err);
return smmu;
}