// SPDX-License-Identifier: GPL-2.0
/*
* IOMMU API for Renesas VMSA-compatible IPMMU
* Author: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
*
* Copyright (C) 2014 Renesas Electronics Corporation
*/
#include <linux/bitmap.h>
#include <linux/delay.h>
#include <linux/dma-iommu.h>
#include <linux/dma-mapping.h>
#include <linux/err.h>
#include <linux/export.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/io-pgtable.h>
#include <linux/iommu.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_iommu.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/sizes.h>
#include <linux/slab.h>
#include <linux/sys_soc.h>
#if defined([31mCONFIG_ARM[0m) && !defined([31mCONFIG_IOMMU_DMA[0m)
#include <asm/dma-iommu.h>
#include <asm/pgalloc.h>
#else
#define arm_iommu_create_mapping(...) NULL
#define arm_iommu_attach_device(...) -ENODEV
#define arm_iommu_release_mapping(...) do {} while (0)
#define arm_iommu_detach_device(...) do {} while (0)
#endif
#define IPMMU_CTX_MAX 8U
#define IPMMU_CTX_INVALID -1
#define IPMMU_UTLB_MAX 48U
struct ipmmu_features {
bool use_ns_alias_offset;
bool has_cache_leaf_nodes;
unsigned int number_of_contexts;
unsigned int num_utlbs;
bool setup_imbuscr;
bool twobit_imttbcr_sl0;
bool reserved_context;
bool cache_snoop;
};
struct ipmmu_vmsa_device {
struct device *dev;
void __iomem *base;
struct iommu_device iommu;
struct ipmmu_vmsa_device *root;
const struct ipmmu_features *features;
unsigned int num_ctx;
spinlock_t lock; /* Protects ctx and domains[] */
DECLARE_BITMAP(ctx, IPMMU_CTX_MAX);
struct ipmmu_vmsa_domain *domains[IPMMU_CTX_MAX];
s8 utlb_ctx[IPMMU_UTLB_MAX];
struct iommu_group *group;
struct dma_iommu_mapping *mapping;
};
struct ipmmu_vmsa_domain {
struct ipmmu_vmsa_device *mmu;
struct iommu_domain io_domain;
struct io_pgtable_cfg cfg;
struct io_pgtable_ops *iop;
unsigned int context_id;
struct mutex mutex; /* Protects mappings */
};
static struct ipmmu_vmsa_domain *to_vmsa_domain(struct iommu_domain *dom)
{
return container_of(dom, struct ipmmu_vmsa_domain, io_domain);
}
static struct ipmmu_vmsa_device *to_ipmmu(struct device *dev)
{
struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
return fwspec ? fwspec->iommu_priv : NULL;
}
#define TLB_LOOP_TIMEOUT 100 /* 100us */
/* -----------------------------------------------------------------------------
* Registers Definition
*/
#define IM_NS_ALIAS_OFFSET 0x800
#define IM_CTX_SIZE 0x40
#define IMCTR 0x0000
#define IMCTR_TRE (1 << 17)
#define IMCTR_AFE (1 << 16)
#define IMCTR_RTSEL_MASK (3 << 4)
#define IMCTR_RTSEL_SHIFT 4
#define IMCTR_TREN (1 << 3)
#define IMCTR_INTEN (1 << 2)
#define IMCTR_FLUSH (1 << 1)
#define IMCTR_MMUEN (1 << 0)
#define IMCAAR 0x0004
#define IMTTBCR 0x0008
#define IMTTBCR_EAE (1 << 31)
#define IMTTBCR_PMB (1 << 30)
#define IMTTBCR_SH1_NON_SHAREABLE (0 << 28) /* R-Car Gen2 only */
#define IMTTBCR_SH1_OUTER_SHAREABLE (2 << 28) /* R-Car Gen2 only */
#define IMTTBCR_SH1_INNER_SHAREABLE (3 << 28) /* R-Car Gen2 only */
#define IMTTBCR_SH1_MASK (3 << 28) /* R-Car Gen2 only */
#define IMTTBCR_ORGN1_NC (0 << 26) /* R-Car Gen2 only */
#define IMTTBCR_ORGN1_WB_WA (1 << 26) /* R-Car Gen2 only */
#define IMTTBCR_ORGN1_WT (2 << 26) /* R-Car Gen2 only */
#define IMTTBCR_ORGN1_WB (3 << 26) /* R-Car Gen2 only */
#define IMTTBCR_ORGN1_MASK (3 << 26) /* R-Car Gen2 only */
#define IMTTBCR_IRGN1_NC (0 << 24) /* R-Car Gen2 only */
#define IMTTBCR_IRGN1_WB_WA (1 << 24) /* R-Car Gen2 only */
#define IMTTBCR_IRGN1_WT (2 << 24) /* R-Car Gen2 only */
#define IMTTBCR_IRGN1_WB (3 << 24) /* R-Car Gen2 only */
#define IMTTBCR_IRGN1_MASK (3 << 24) /* R-Car Gen2 only */
#define IMTTBCR_TSZ1_MASK (7 << 16)
#define IMTTBCR_TSZ1_SHIFT 16
#define IMTTBCR_SH0_NON_SHAREABLE (0 << 12) /* R-Car Gen2 only */
#define IMTTBCR_SH0_OUTER_SHAREABLE (2 << 12) /* R-Car Gen2 only */
#define IMTTBCR_SH0_INNER_SHAREABLE (3 << 12) /* R-Car Gen2 only */
#define IMTTBCR_SH0_MASK (3 << 12) /* R-Car Gen2 only */
#define IMTTBCR_ORGN0_NC (0 << 10) /* R-Car Gen2 only */
#define IMTTBCR_ORGN0_WB_WA (1 << 10) /* R-Car Gen2 only */
#define IMTTBCR_ORGN0_WT (2 << 10) /* R-Car Gen2 only */
#define IMTTBCR_ORGN0_WB (3 << 10) /* R-Car Gen2 only */
#define IMTTBCR_ORGN0_MASK (3 << 10) /* R-Car Gen2 only */
#define IMTTBCR_IRGN0_NC (0 << 8) /* R-Car Gen2 only */
#define IMTTBCR_IRGN0_WB_WA (1 << 8) /* R-Car Gen2 only */
#define IMTTBCR_IRGN0_WT (2 << 8) /* R-Car Gen2 only */
#define IMTTBCR_IRGN0_WB (3 << 8) /* R-Car Gen2 only */
#define IMTTBCR_IRGN0_MASK (3 << 8) /* R-Car Gen2 only */
#define IMTTBCR_SL0_TWOBIT_LVL_3 (0 << 6) /* R-Car Gen3 only */
#define IMTTBCR_SL0_TWOBIT_LVL_2 (1 << 6) /* R-Car Gen3 only */
#define IMTTBCR_SL0_TWOBIT_LVL_1 (2 << 6) /* R-Car Gen3 only */
#define IMTTBCR_SL0_LVL_2 (0 << 4)
#define IMTTBCR_SL0_LVL_1 (1 << 4)
#define IMTTBCR_TSZ0_MASK (7 << 0)
#define IMTTBCR_TSZ0_SHIFT O
#define IMBUSCR 0x000c
#define IMBUSCR_DVM (1 << 2)
#define IMBUSCR_BUSSEL_SYS (0 << 0)
#define IMBUSCR_BUSSEL_CCI (1 << 0)
#define IMBUSCR_BUSSEL_IMCAAR (2 << 0)
#define IMBUSCR_BUSSEL_CCI_IMCAAR (3 << 0)
#define IMBUSCR_BUSSEL_MASK (3 << 0)
#define IMTTLBR0 0x0010
#define IMTTUBR0 0x0014
#define IMTTLBR1 0x0018
#define IMTTUBR1 0x001c
#define IMSTR 0x0020
#define IMSTR_ERRLVL_MASK (3 << 12)
#define IMSTR_ERRLVL_SHIFT 12
#define IMSTR_ERRCODE_TLB_FORMAT (1 << 8)
#define IMSTR_ERRCODE_ACCESS_PERM (4 << 8)
#define IMSTR_ERRCODE_SECURE_ACCESS (5 << 8)
#define IMSTR_ERRCODE_MASK (7 << 8)
#define IMSTR_MHIT (1 << 4)
#define IMSTR_ABORT (1 << 2)
#define IMSTR_PF (1 << 1)
#define IMSTR_TF (1 << 0)
#define IMMAIR0 0x0028
#define IMMAIR1 0x002c
#define IMMAIR_ATTR_MASK 0xff
#define IMMAIR_ATTR_DEVICE 0x04
#define IMMAIR_ATTR_NC 0x44
#define IMMAIR_ATTR_WBRWA 0xff
#define IMMAIR_ATTR_SHIFT(n) ((n) << 3)
#define IMMAIR_ATTR_IDX_NC 0
#define IMMAIR_ATTR_IDX_WBRWA 1
#define IMMAIR_ATTR_IDX_DEV 2
#define IMELAR 0x0030 /* IMEAR on R-Car Gen2 */
#define IMEUAR 0x0034 /* R-Car Gen3 only */
#define IMPCTR 0x0200
#define IMPSTR 0x0208
#define IMPEAR 0x020c
#define IMPMBA(n) (0x0280 + ((n) * 4))
#define IMPMBD(n) (0x02c0 + ((n) * 4))
#define IMUCTR(n) ((n) < 32 ? IMUCTR0(n) : IMUCTR32(n))
#define IMUCTR0(n) (0x0300 + ((n) * 16))
#define IMUCTR32(n) (0x0600 + (((n) - 32) * 16))
#define IMUCTR_FIXADDEN (1 << 31)
#define IMUCTR_FIXADD_MASK (0xff << 16)
#define IMUCTR_FIXADD_SHIFT 16
#define IMUCTR_TTSEL_MMU(n) ((n) << 4)
#define IMUCTR_TTSEL_PMB (8 << 4)
#define IMUCTR_TTSEL_MASK (15 << 4)
#define IMUCTR_FLUSH (1 << 1)
#define IMUCTR_MMUEN (1 << 0)
#define IMUASID(n) ((n) < 32 ? IMUASID0(n) : IMUASID32(n))
#define IMUASID0(n) (0x0308 + ((n) * 16))
#define IMUASID32(n) (0x0608 + (((n) - 32) * 16))
#define IMUASID_ASID8_MASK (0xff << 8)
#define IMUASID_ASID8_SHIFT 8
#define IMUASID_ASID0_MASK (0xff << 0)
#define IMUASID_ASID0_SHIFT 0
/* -----------------------------------------------------------------------------
* Root device handling
*/
static struct platform_driver ipmmu_driver;
static bool ipmmu_is_root(struct ipmmu_vmsa_device *mmu)
{
return mmu->root == mmu;
}
static int __ipmmu_check_device(struct device *dev, void *data)
{
struct ipmmu_vmsa_device *mmu = dev_get_drvdata(dev);
struct ipmmu_vmsa_device **rootp = data;
if (ipmmu_is_root(mmu))
*rootp = mmu;
return 0;
}
static struct ipmmu_vmsa_device *ipmmu_find_root(void)
{
struct ipmmu_vmsa_device *root = NULL;
return driver_for_each_device(&ipmmu_driver.driver, NULL, &root,
__ipmmu_check_device) == 0 ? root : NULL;
}
/* -----------------------------------------------------------------------------
* Read/Write Access
*/
static u32 ipmmu_read(struct ipmmu_vmsa_device *mmu, unsigned int offset)
{
return ioread32(mmu->base + offset);
}
static void ipmmu_write(struct ipmmu_vmsa_device *mmu, unsigned int offset,
u32 data)
{
iowrite32(data, mmu->base + offset);
}
static u32 ipmmu_ctx_read_root(struct ipmmu_vmsa_domain *domain,
unsigned int reg)
{
return ipmmu_read(domain->mmu->root,
domain->context_id * IM_CTX_SIZE + reg);
}
static void ipmmu_ctx_write_root(struct ipmmu_vmsa_domain *domain,
unsigned int reg, u32 data)
{
ipmmu_write(domain->mmu->root,
domain->context_id * IM_CTX_SIZE + reg, data);
}
static void ipmmu_ctx_write_all(struct ipmmu_vmsa_domain *domain,
unsigned int reg, u32 data)
{
if (domain->mmu != domain->mmu->root)
ipmmu_write(domain->mmu,
domain->context_id * IM_CTX_SIZE + reg, data);
ipmmu_write(domain->mmu->root,
domain->context_id * IM_CTX_SIZE + reg, data);
}
/* -----------------------------------------------------------------------------
* TLB and microTLB Management
*/
/* Wait for any pending TLB invalidations to complete */
static void ipmmu_tlb_sync(struct ipmmu_vmsa_domain *domain)
{
unsigned int count = 0;
while (ipmmu_ctx_read_root(domain, IMCTR) & IMCTR_FLUSH) {
cpu_relax();
if (++count == TLB_LOOP_TIMEOUT) {
dev_err_ratelimited(domain->mmu->dev,
"TLB sync timed out -- MMU may be deadlocked\n");
return;
}
udelay(1);
}
}
static void ipmmu_tlb_invalidate(struct ipmmu_vmsa_domain *domain)
{
u32 reg;
reg = ipmmu_ctx_read_root(domain, IMCTR);
reg |= IMCTR_FLUSH;
ipmmu_ctx_write_all(domain, IMCTR, reg);
ipmmu_tlb_sync(domain);
}
/*
* Enable MMU translation for the microTLB.
*/
static void ipmmu_utlb_enable(struct ipmmu_vmsa_domain *domain,
unsigned int utlb)
{
struct ipmmu_vmsa_device *mmu = domain->mmu;
/*
* TODO: Reference-count the microTLB as several bus masters can be
* connected to the same microTLB.
*/
/* TODO: What should we set the ASID to ? */
ipmmu_write(mmu, IMUASID(utlb), 0);
/* TODO: Do we need to flush the microTLB ? */
ipmmu_write(mmu, IMUCTR(utlb),
IMUCTR_TTSEL_MMU(domain->context_id) | IMUCTR_FLUSH |
IMUCTR_MMUEN);
mmu->utlb_ctx[utlb] = domain->context_id;
}
/*
* Disable MMU translation for the microTLB.
*/
static void ipmmu_utlb_disable(struct ipmmu_vmsa_domain *domain,
unsigned int utlb)
{
struct ipmmu_vmsa_device *mmu = domain->mmu;
ipmmu_write(mmu, IMUCTR(utlb), 0);
mmu->utlb_ctx[utlb] = IPMMU_CTX_INVALID;
}
static void ipmmu_tlb_flush_all(void *cookie)
{
struct ipmmu_vmsa_domain *domain = cookie;
ipmmu_tlb_invalidate(domain);
}
static void ipmmu_tlb_flush(unsigned long iova, size_t size,
size_t granule, void *cookie)
{
ipmmu_tlb_flush_all(cookie);
}
static const struct iommu_flush_ops ipmmu_flush_ops = {
.tlb_flush_all = ipmmu_tlb_flush_all,
.tlb_flush_walk = ipmmu_tlb_flush,
.tlb_flush_leaf = ipmmu_tlb_flush,
};
/* -----------------------------------------------------------------------------
* Domain/Context Management
*/
static int ipmmu_domain_allocate_context(struct ipmmu_vmsa_device *mmu,
struct ipmmu_vmsa_domain *domain)
{
unsigned long flags;
int ret;
spin_lock_irqsave(&mmu->lock, flags);
ret = find_first_zero_bit(mmu->ctx, mmu->num_ctx);
if (ret != mmu->num_ctx) {
mmu->domains[ret] = domain;
set_bit(ret, mmu->ctx);
} else
ret = -EBUSY;
spin_unlock_irqrestore(&mmu->lock, flags);
return ret;
}
static void ipmmu_domain_free_context(struct ipmmu_vmsa_device *mmu,
unsigned int context_id)
{
unsigned long flags;
spin_lock_irqsave(&mmu->lock, flags);
clear_bit(context_id, mmu->ctx);
mmu->domains[context_id] = NULL;
spin_unlock_irqrestore(&mmu->lock, flags);
}
static void ipmmu_domain_setup_context(struct ipmmu_vmsa_domain *domain)
{
u64 ttbr;
u32 tmp;
/* TTBR0 */
ttbr = domain->cfg.arm_lpae_s1_cfg.ttbr[0];
ipmmu_ctx_write_root(domain, IMTTLBR0, ttbr);
ipmmu_ctx_write_root(domain, IMTTUBR0, ttbr >> 32);
/*
* TTBCR
* We use long descriptors and allocate the whole 32-bit VA space to
* TTBR0.
*/
if (domain->mmu->features->twobit_imttbcr_sl0)
tmp = IMTTBCR_SL0_TWOBIT_LVL_1;
else
tmp = IMTTBCR_SL0_LVL_1;
if (domain->mmu->features->cache_snoop)
tmp |= IMTTBCR_SH0_INNER_SHAREABLE | IMTTBCR_ORGN0_WB_WA |
IMTTBCR_IRGN0_WB_WA;
ipmmu_ctx_write_root(domain, IMTTBCR, IMTTBCR_EAE | tmp);
/* MAIR0 */
ipmmu_ctx_write_root(domain, IMMAIR0,
domain->cfg.arm_lpae_s1_cfg.mair[0]);
/* IMBUSCR */
if (domain->mmu->features->setup_imbuscr)
ipmmu_ctx_write_root(domain, IMBUSCR,
ipmmu_ctx_read_root(domain, IMBUSCR) &
~(IMBUSCR_DVM | IMBUSCR_BUSSEL_MASK));
/*
* IMSTR
* Clear all interrupt flags.
*/
ipmmu_ctx_write_root(domain, IMSTR, ipmmu_ctx_read_root(domain, IMSTR));
/*
* IMCTR
* Enable the MMU and interrupt generation. The long-descriptor
* translation table format doesn't use TEX remapping. Don't enable AF
* software management as we have no use for it. Flush the TLB as
* required when modifying the context registers.
*/
ipmmu_ctx_write_all(domain, IMCTR,
IMCTR_INTEN | IMCTR_FLUSH | IMCTR_MMUEN);
}
static int ipmmu_domain_init_context(struct ipmmu_vmsa_domain *domain)
{
int ret;
/*
* Allocate the page table operations.
*
* VMSA states in section B3.6.3 "Control of Secure or Non-secure memory
* access, Long-descriptor format" that the NStable bit being set in a
* table descriptor will result in the NStable and NS bits of all child
* entries being ignored and considered as being set. The IPMMU seems
* not to comply with this, as it generates a secure access page fault
* if any of the NStable and NS bits isn't set when running in
* non-secure mode.
*/
domain->cfg.quirks = IO_PGTABLE_QUIRK_ARM_NS;
domain->cfg.pgsize_bitmap = SZ_1G | SZ_2M | SZ_4K;
domain->cfg.ias = 32;
domain->cfg.oas = 40;
domain->cfg.tlb = &ipmmu_flush_ops;
domain->io_domain.geometry.aperture_end = DMA_BIT_MASK(32);
domain->io_domain.geometry.force_aperture = true;
/*
* TODO: Add support for coherent walk through CCI with DVM and remove
* cache handling. For now, delegate it to the io-pgtable code.
*/
domain->cfg.coherent_walk = false;
domain->cfg.iommu_dev = domain->mmu->root->dev;
/*
* Find an unused context.
*/
ret = ipmmu_domain_allocate_context(domain->mmu->root, domain);
if (ret < 0)
return ret;
domain->context_id = ret;
domain->iop = alloc_io_pgtable_ops(ARM_32_LPAE_S1, &domain->cfg,
domain);
if (!domain->iop) {
ipmmu_domain_free_context(domain->mmu->root,
domain->context_id);
return -EINVAL;
}
ipmmu_domain_setup_context(domain);
return 0;
}
static void ipmmu_domain_destroy_context(struct ipmmu_vmsa_domain *domain)
{
if (!domain->mmu)
return;
/*
* Disable the context. Flush the TLB as required when modifying the
* context registers.
*
* TODO: Is TLB flush really needed ?
*/
ipmmu_ctx_write_all(domain, IMCTR, IMCTR_FLUSH);
ipmmu_tlb_sync(domain);
ipmmu_domain_free_context(domain->mmu->root, domain->context_id);
}
/* -----------------------------------------------------------------------------
* Fault Handling
*/
static irqreturn_t ipmmu_domain_irq(struct ipmmu_vmsa_domain *domain)
{
const u32 err_mask = IMSTR_MHIT | IMSTR_ABORT | IMSTR_PF | IMSTR_TF;
struct ipmmu_vmsa_device *mmu = domain->mmu;
unsigned long iova;
u32 status;
status = ipmmu_ctx_read_root(domain, IMSTR);
if (!(status & err_mask))
return IRQ_NONE;
iova = ipmmu_ctx_read_root(domain, IMELAR);
if (IS_ENABLED([31mCONFIG_64BIT[0m))
iova |= (u64)ipmmu_ctx_read_root(domain, IMEUAR) << 32;
/*
* Clear the error status flags. Unlike traditional interrupt flag
* registers that must be cleared by writing 1, this status register
* seems to require 0. The error address register must be read before,
* otherwise its value will be 0.
*/
ipmmu_ctx_write_root(domain, IMSTR, 0);
/* Log fatal errors. */
if (status & IMSTR_MHIT)
dev_err_ratelimited(mmu->dev, "Multiple TLB hits @0x%lx\n",
iova);
if (status & IMSTR_ABORT)
dev_err_ratelimited(mmu->dev, "Page Table Walk Abort @0x%lx\n",
iova);
if (!(status & (IMSTR_PF | IMSTR_TF)))
return IRQ_NONE;
/*
* Try to handle page faults and translation faults.
*
* TODO: We need to look up the faulty device based on the I/O VA. Use
* the IOMMU device for now.
*/
if (!report_iommu_fault(&domain->io_domain, mmu->dev, iova, 0))
return IRQ_HANDLED;
dev_err_ratelimited(mmu->dev,
"Unhandled fault: status 0x%08x iova 0x%lx\n",
status, iova);
return IRQ_HANDLED;
}
static irqreturn_t ipmmu_irq(int irq, void *dev)
{
struct ipmmu_vmsa_device *mmu = dev;
irqreturn_t status = IRQ_NONE;
unsigned int i;
unsigned long flags;
spin_lock_irqsave(&mmu->lock, flags);
/*
* Check interrupts for all active contexts.
*/
for (i = 0; i < mmu->num_ctx; i++) {
if (!mmu->domains[i])
continue;
if (ipmmu_domain_irq(mmu->domains[i]) == IRQ_HANDLED)
status = IRQ_HANDLED;
}
spin_unlock_irqrestore(&mmu->lock, flags);
return status;
}
/* -----------------------------------------------------------------------------
* IOMMU Operations
*/
static struct iommu_domain *__ipmmu_domain_alloc(unsigned type)
{
struct ipmmu_vmsa_domain *domain;
domain = kzalloc(sizeof(*domain), GFP_KERNEL);
if (!domain)
return NULL;
mutex_init(&domain->mutex);
return &domain->io_domain;
}
static struct iommu_domain *ipmmu_domain_alloc(unsigned type)
{
struct iommu_domain *io_domain = NULL;
switch (type) {
case IOMMU_DOMAIN_UNMANAGED:
io_domain = __ipmmu_domain_alloc(type);
break;
case IOMMU_DOMAIN_DMA:
io_domain = __ipmmu_domain_alloc(type);
if (io_domain && iommu_get_dma_cookie(io_domain)) {
kfree(io_domain);
io_domain = NULL;
}
break;
}
return io_domain;
}
static void ipmmu_domain_free(struct iommu_domain *io_domain)
{
struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
/*
* Free the domain resources. We assume that all devices have already
* been detached.
*/
iommu_put_dma_cookie(io_domain);
ipmmu_domain_destroy_context(domain);
free_io_pgtable_ops(domain->iop);
kfree(domain);
}
static int ipmmu_attach_device(struct iommu_domain *io_domain,
struct device *dev)
{
struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
struct ipmmu_vmsa_device *mmu = to_ipmmu(dev);
struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
unsigned int i;
int ret = 0;
if (!mmu) {
dev_err(dev, "Cannot attach to IPMMU\n");
return -ENXIO;
}
mutex_lock(&domain->mutex);
if (!domain->mmu) {
/* The domain hasn't been used yet, initialize it. */
domain->mmu = mmu;
ret = ipmmu_domain_init_context(domain);
if (ret < 0) {
dev_err(dev, "Unable to initialize IPMMU context\n");
domain->mmu = NULL;
} else {
dev_info(dev, "Using IPMMU context %u\n",
domain->context_id);
}
} else if (domain->mmu != mmu) {
/*
* Something is wrong, we can't attach two devices using
* different IOMMUs to the same domain.
*/
dev_err(dev, "Can't attach IPMMU %s to domain on IPMMU %s\n",
dev_name(mmu->dev), dev_name(domain->mmu->dev));
ret = -EINVAL;
} else
dev_info(dev, "Reusing IPMMU context %u\n", domain->context_id);
mutex_unlock(&domain->mutex);
if (ret < 0)
return ret;
for (i = 0; i < fwspec->num_ids; ++i)
ipmmu_utlb_enable(domain, fwspec->ids[i]);
return 0;
}
static void ipmmu_detach_device(struct iommu_domain *io_domain,
struct device *dev)
{
struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
unsigned int i;
for (i = 0; i < fwspec->num_ids; ++i)
ipmmu_utlb_disable(domain, fwspec->ids[i]);
/*
* TODO: Optimize by disabling the context when no device is attached.
*/
}
static int ipmmu_map(struct iommu_domain *io_domain, unsigned long iova,
phys_addr_t paddr, size_t size, int prot)
{
struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
if (!domain)
return -ENODEV;
return domain->iop->map(domain->iop, iova, paddr, size, prot);
}
static size_t ipmmu_unmap(struct iommu_domain *io_domain, unsigned long iova,
size_t size, struct iommu_iotlb_gather *gather)
{
struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
return domain->iop->unmap(domain->iop, iova, size, gather);
}
static void ipmmu_flush_iotlb_all(struct iommu_domain *io_domain)
{
struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
if (domain->mmu)
ipmmu_tlb_flush_all(domain);
}
static void ipmmu_iotlb_sync(struct iommu_domain *io_domain,
struct iommu_iotlb_gather *gather)
{
ipmmu_flush_iotlb_all(io_domain);
}
static phys_addr_t ipmmu_iova_to_phys(struct iommu_domain *io_domain,
dma_addr_t iova)
{
struct ipmmu_vmsa_domain *domain = to_vmsa_domain(io_domain);
/* TODO: Is locking needed ? */
return domain->iop->iova_to_phys(domain->iop, iova);
}
static int ipmmu_init_platform_device(struct device *dev,
struct of_phandle_args *args)
{
struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
struct platform_device *ipmmu_pdev;
ipmmu_pdev = of_find_device_by_node(args->np);
if (!ipmmu_pdev)
return -ENODEV;
fwspec->iommu_priv = platform_get_drvdata(ipmmu_pdev);
return 0;
}
static const struct soc_device_attribute soc_rcar_gen3[] = {
{ .soc_id = "r8a774a1", },
{ .soc_id = "r8a774c0", },
{ .soc_id = "r8a7795", },
{ .soc_id = "r8a7796", },
{ .soc_id = "r8a77965", },
{ .soc_id = "r8a77970", },
{ .soc_id = "r8a77990", },
{ .soc_id = "r8a77995", },
{ /* sentinel */ }
};
static const struct soc_device_attribute soc_rcar_gen3_whitelist[] = {
{ .soc_id = "r8a774c0", },
{ .soc_id = "r8a7795", .revision = "ES3.*" },
{ .soc_id = "r8a77965", },
{ .soc_id = "r8a77990", },
{ .soc_id = "r8a77995", },
{ /* sentinel */ }
};
static const char * const rcar_gen3_slave_whitelist[] = {
};
static bool ipmmu_slave_whitelist(struct device *dev)
{
unsigned int i;
/*
* For R-Car Gen3 use a white list to opt-in slave devices.
* For Other SoCs, this returns true anyway.
*/
if (!soc_device_match(soc_rcar_gen3))
return true;
/* Check whether this R-Car Gen3 can use the IPMMU correctly or not */
if (!soc_device_match(soc_rcar_gen3_whitelist))
return false;
/* Check whether this slave device can work with the IPMMU */
for (i = 0; i < ARRAY_SIZE(rcar_gen3_slave_whitelist); i++) {
if (!strcmp(dev_name(dev), rcar_gen3_slave_whitelist[i]))
return true;
}
/* Otherwise, do not allow use of IPMMU */
return false;
}
static int ipmmu_of_xlate(struct device *dev,
struct of_phandle_args *spec)
{
if (!ipmmu_slave_whitelist(dev))
return -ENODEV;
iommu_fwspec_add_ids(dev, spec->args, 1);
/* Initialize once - xlate() will call multiple times */
if (to_ipmmu(dev))
return 0;
return ipmmu_init_platform_device(dev, spec);
}
static int ipmmu_init_arm_mapping(struct device *dev)
{
struct ipmmu_vmsa_device *mmu = to_ipmmu(dev);
struct iommu_group *group;
int ret;
/* Create a device group and add the device to it. */
group = iommu_group_alloc();
if (IS_ERR(group)) {
dev_err(dev, "Failed to allocate IOMMU group\n");
return PTR_ERR(group);
}
ret = iommu_group_add_device(group, dev);
iommu_group_put(group);
if (ret < 0) {
dev_err(dev, "Failed to add device to IPMMU group\n");
return ret;
}
/*
* Create the ARM mapping, used by the ARM DMA mapping core to allocate
* VAs. This will allocate a corresponding IOMMU domain.
*
* TODO:
* - Create one mapping per context (TLB).
* - Make the mapping size configurable ? We currently use a 2GB mapping
* at a 1GB offset to ensure that NULL VAs will fault.
*/
if (!mmu->mapping) {
struct dma_iommu_mapping *mapping;
mapping = arm_iommu_create_mapping(&platform_bus_type,
SZ_1G, SZ_2G);
if (IS_ERR(mapping)) {
dev_err(mmu->dev, "failed to create ARM IOMMU mapping\n");
ret = PTR_ERR(mapping);
goto error;
}
mmu->mapping = mapping;
}
/* Attach the ARM VA mapping to the device. */
ret = arm_iommu_attach_device(dev, mmu->mapping);
if (ret < 0) {
dev_err(dev, "Failed to attach device to VA mapping\n");
goto error;
}
return 0;
error:
iommu_group_remove_device(dev);
if (mmu->mapping)
arm_iommu_release_mapping(mmu->mapping);
return ret;
}
static int ipmmu_add_device(struct device *dev)
{
struct ipmmu_vmsa_device *mmu = to_ipmmu(dev);
struct iommu_group *group;
int ret;
/*
* Only let through devices that have been verified in xlate()
*/
if (!mmu)
return -ENODEV;
if (IS_ENABLED([31mCONFIG_ARM[0m) && !IS_ENABLED([31mCONFIG_IOMMU_DMA[0m)) {
ret = ipmmu_init_arm_mapping(dev);
if (ret)
return ret;
} else {
group = iommu_group_get_for_dev(dev);
if (IS_ERR(group))
return PTR_ERR(group);
iommu_group_put(group);
}
iommu_device_link(&mmu->iommu, dev);
return 0;
}
static void ipmmu_remove_device(struct device *dev)
{
struct ipmmu_vmsa_device *mmu = to_ipmmu(dev);
iommu_device_unlink(&mmu->iommu, dev);
arm_iommu_detach_device(dev);
iommu_group_remove_device(dev);
}
static struct iommu_group *ipmmu_find_group(struct device *dev)
{
struct ipmmu_vmsa_device *mmu = to_ipmmu(dev);
struct iommu_group *group;
if (mmu->group)
return iommu_group_ref_get(mmu->group);
group = iommu_group_alloc();
if (!IS_ERR(group))
mmu->group = group;
return group;
}
static const struct iommu_ops ipmmu_ops = {
.domain_alloc = ipmmu_domain_alloc,
.domain_free = ipmmu_domain_free,
.attach_dev = ipmmu_attach_device,
.detach_dev = ipmmu_detach_device,
.map = ipmmu_map,
.unmap = ipmmu_unmap,
.flush_iotlb_all = ipmmu_flush_iotlb_all,
.iotlb_sync = ipmmu_iotlb_sync,
.iova_to_phys = ipmmu_iova_to_phys,
.add_device = ipmmu_add_device,
.remove_device = ipmmu_remove_device,
.device_group = ipmmu_find_group,
.pgsize_bitmap = SZ_1G | SZ_2M | SZ_4K,
.of_xlate = ipmmu_of_xlate,
};
/* -----------------------------------------------------------------------------
* Probe/remove and init
*/
static void ipmmu_device_reset(struct ipmmu_vmsa_device *mmu)
{
unsigned int i;
/* Disable all contexts. */
for (i = 0; i < mmu->num_ctx; ++i)
ipmmu_write(mmu, i * IM_CTX_SIZE + IMCTR, 0);
}
static const struct ipmmu_features ipmmu_features_default = {
.use_ns_alias_offset = true,
.has_cache_leaf_nodes = false,
.number_of_contexts = 1, /* software only tested with one context */
.num_utlbs = 32,
.setup_imbuscr = true,
.twobit_imttbcr_sl0 = false,
.reserved_context = false,
.cache_snoop = true,
};
static const struct ipmmu_features ipmmu_features_rcar_gen3 = {
.use_ns_alias_offset = false,
.has_cache_leaf_nodes = true,
.number_of_contexts = 8,
.num_utlbs = 48,
.setup_imbuscr = false,
.twobit_imttbcr_sl0 = true,
.reserved_context = true,
.cache_snoop = false,
};
static const struct of_device_id ipmmu_of_ids[] = {
{
.compatible = "renesas,ipmmu-vmsa",
.data = &ipmmu_features_default,
}, {
.compatible = "renesas,ipmmu-r8a774a1",
.data = &ipmmu_features_rcar_gen3,
}, {
.compatible = "renesas,ipmmu-r8a774c0",
.data = &ipmmu_features_rcar_gen3,
}, {
.compatible = "renesas,ipmmu-r8a7795",
.data = &ipmmu_features_rcar_gen3,
}, {
.compatible = "renesas,ipmmu-r8a7796",
.data = &ipmmu_features_rcar_gen3,
}, {
.compatible = "renesas,ipmmu-r8a77965",
.data = &ipmmu_features_rcar_gen3,
}, {
.compatible = "renesas,ipmmu-r8a77970",
.data = &ipmmu_features_rcar_gen3,
}, {
.compatible = "renesas,ipmmu-r8a77990",
.data = &ipmmu_features_rcar_gen3,
}, {
.compatible = "renesas,ipmmu-r8a77995",
.data = &ipmmu_features_rcar_gen3,
}, {
/* Terminator */
},
};
static int ipmmu_probe(struct platform_device *pdev)
{
struct ipmmu_vmsa_device *mmu;
struct resource *res;
int irq;
int ret;
mmu = devm_kzalloc(&pdev->dev, sizeof(*mmu), GFP_KERNEL);
if (!mmu) {
dev_err(&pdev->dev, "cannot allocate device data\n");
return -ENOMEM;
}
mmu->dev = &pdev->dev;
spin_lock_init(&mmu->lock);
bitmap_zero(mmu->ctx, IPMMU_CTX_MAX);
mmu->features = of_device_get_match_data(&pdev->dev);
memset(mmu->utlb_ctx, IPMMU_CTX_INVALID, mmu->features->num_utlbs);
dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(40));
/* Map I/O memory and request IRQ. */
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
mmu->base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(mmu->base))
return PTR_ERR(mmu->base);
/*
* The IPMMU has two register banks, for secure and non-secure modes.
* The bank mapped at the beginning of the IPMMU address space
* corresponds to the running mode of the CPU. When running in secure
* mode the non-secure register bank is also available at an offset.
*
* Secure mode operation isn't clearly documented and is thus currently
* not implemented in the driver. Furthermore, preliminary tests of
* non-secure operation with the main register bank were not successful.
* Offset the registers base unconditionally to point to the non-secure
* alias space for now.
*/
if (mmu->features->use_ns_alias_offset)
mmu->base += IM_NS_ALIAS_OFFSET;
mmu->num_ctx = min(IPMMU_CTX_MAX, mmu->features->number_of_contexts);
/*
* Determine if this IPMMU instance is a root device by checking for
* the lack of has_cache_leaf_nodes flag or renesas,ipmmu-main property.
*/
if (!mmu->features->has_cache_leaf_nodes ||
!of_find_property(pdev->dev.of_node, "renesas,ipmmu-main", NULL))
mmu->root = mmu;
else
mmu->root = ipmmu_find_root();
/*
* Wait until the root device has been registered for sure.
*/
if (!mmu->root)
return -EPROBE_DEFER;
/* Root devices have mandatory IRQs */
if (ipmmu_is_root(mmu)) {
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return irq;
ret = devm_request_irq(&pdev->dev, irq, ipmmu_irq, 0,
dev_name(&pdev->dev), mmu);
if (ret < 0) {
dev_err(&pdev->dev, "failed to request IRQ %d\n", irq);
return ret;
}
ipmmu_device_reset(mmu);
if (mmu->features->reserved_context) {
dev_info(&pdev->dev, "IPMMU context 0 is reserved\n");
set_bit(0, mmu->ctx);
}
}
/*
* Register the IPMMU to the IOMMU subsystem in the following cases:
* - R-Car Gen2 IPMMU (all devices registered)
* - R-Car Gen3 IPMMU (leaf devices only - skip root IPMMU-MM device)
*/
if (!mmu->features->has_cache_leaf_nodes || !ipmmu_is_root(mmu)) {
ret = iommu_device_sysfs_add(&mmu->iommu, &pdev->dev, NULL,
dev_name(&pdev->dev));
if (ret)
return ret;
iommu_device_set_ops(&mmu->iommu, &ipmmu_ops);
iommu_device_set_fwnode(&mmu->iommu,
&pdev->dev.of_node->fwnode);
ret = iommu_device_register(&mmu->iommu);
if (ret)
return ret;
#if defined([31mCONFIG_IOMMU_DMA[0m)
if (!iommu_present(&platform_bus_type))
bus_set_iommu(&platform_bus_type, &ipmmu_ops);
#endif
}
/*
* We can't create the ARM mapping here as it requires the bus to have
* an IOMMU, which only happens when bus_set_iommu() is called in
* ipmmu_init() after the probe function returns.
*/
platform_set_drvdata(pdev, mmu);
return 0;
}
static int ipmmu_remove(struct platform_device *pdev)
{
struct ipmmu_vmsa_device *mmu = platform_get_drvdata(pdev);
iommu_device_sysfs_remove(&mmu->iommu);
iommu_device_unregister(&mmu->iommu);
arm_iommu_release_mapping(mmu->mapping);
ipmmu_device_reset(mmu);
return 0;
}
#ifdef [31mCONFIG_PM_SLEEP[0m
static int ipmmu_resume_noirq(struct device *dev)
{
struct ipmmu_vmsa_device *mmu = dev_get_drvdata(dev);
unsigned int i;
/* Reset root MMU and restore contexts */
if (ipmmu_is_root(mmu)) {
ipmmu_device_reset(mmu);
for (i = 0; i < mmu->num_ctx; i++) {
if (!mmu->domains[i])
continue;
ipmmu_domain_setup_context(mmu->domains[i]);
}
}
/* Re-enable active micro-TLBs */
for (i = 0; i < mmu->features->num_utlbs; i++) {
if (mmu->utlb_ctx[i] == IPMMU_CTX_INVALID)
continue;
ipmmu_utlb_enable(mmu->root->domains[mmu->utlb_ctx[i]], i);
}
return 0;
}
static const struct dev_pm_ops ipmmu_pm = {
SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(NULL, ipmmu_resume_noirq)
};
#define DEV_PM_OPS &ipmmu_pm
#else
#define DEV_PM_OPS NULL
#endif /* CONFIG_PM_SLEEP */
static struct platform_driver ipmmu_driver = {
.driver = {
.name = "ipmmu-vmsa",
.of_match_table = of_match_ptr(ipmmu_of_ids),
.pm = DEV_PM_OPS,
},
.probe = ipmmu_probe,
.remove = ipmmu_remove,
};
static int __init ipmmu_init(void)
{
struct device_node *np;
static bool setup_done;
int ret;
if (setup_done)
return 0;
np = of_find_matching_node(NULL, ipmmu_of_ids);
if (!np)
return 0;
of_node_put(np);
ret = platform_driver_register(&ipmmu_driver);
if (ret < 0)
return ret;
#if defined([31mCONFIG_ARM[0m) && !defined([31mCONFIG_IOMMU_DMA[0m)
if (!iommu_present(&platform_bus_type))
bus_set_iommu(&platform_bus_type, &ipmmu_ops);
#endif
setup_done = true;
return 0;
}
subsys_initcall(ipmmu_init);