The main goal is to modify as little the Linux code to be able to port
easily new feature added in Linux repo for the driver.
To achieve that we:
- Add helpers to Linux function not implemented on Xen
- Add callbacks used by Xen to do our own stuff and call Linux ones
- Only modify when required the code which comes from Linux. If so a
comment has been added with /* Xen: ... */ explaining why it's
necessary.
The support for PCI has been commented because it's not yet supported by
Xen ARM and therefore won't compile.
Signed-off-by: Julien Grall <julien.gr...@linaro.org>
---
Changes in v2:
- Add the ACCESS_ONCE definition in the drivers. The patch to
introduce the one in common code has been dropped.
- The include xen/device.h has been dropped in favor of
asm/device.h
---
xen/drivers/passthrough/arm/Makefile | 1 +
xen/drivers/passthrough/arm/smmu.c | 678 +++++++++++++++++++++++++++++++----
2 files changed, 612 insertions(+), 67 deletions(-)
diff --git a/xen/drivers/passthrough/arm/Makefile
b/xen/drivers/passthrough/arm/Makefile
index 0484b79..f4cd26e 100644
--- a/xen/drivers/passthrough/arm/Makefile
+++ b/xen/drivers/passthrough/arm/Makefile
@@ -1 +1,2 @@
obj-y += iommu.o
+obj-y += smmu.o
diff --git a/xen/drivers/passthrough/arm/smmu.c
b/xen/drivers/passthrough/arm/smmu.c
index 8a6514f..373eee8 100644
--- a/xen/drivers/passthrough/arm/smmu.c
+++ b/xen/drivers/passthrough/arm/smmu.c
@@ -18,6 +18,13 @@
*
* Author: Will Deacon <will.dea...@arm.com>
*
+ * Based on Linux drivers/iommu/arm-smmu.c
+ * => commit e6b5be2be4e30037eb551e0ed09dd97bd00d85d3
+ *
+ * Xen modification:
+ * Julien Grall <julien.gr...@linaro.org>
+ * Copyright (C) 2014 Linaro Limited.
+ *
* This driver currently supports:
* - SMMUv1 and v2 implementations
* - Stream-matching and stream-indexing
@@ -28,26 +35,164 @@
* - Context fault reporting
*/
-#define pr_fmt(fmt) "arm-smmu: " fmt
-#include <linux/delay.h>
-#include <linux/dma-mapping.h>
-#include <linux/err.h>
-#include <linux/interrupt.h>
-#include <linux/io.h>
-#include <linux/iommu.h>
-#include <linux/mm.h>
-#include <linux/module.h>
-#include <linux/of.h>
-#include <linux/pci.h>
-#include <linux/platform_device.h>
-#include <linux/slab.h>
-#include <linux/spinlock.h>
-#include <linux/bitops.h>
+#include <xen/config.h>
+#include <xen/delay.h>
+#include <xen/errno.h>
+#include <xen/err.h>
+#include <xen/irq.h>
+#include <xen/lib.h>
+#include <xen/list.h>
+#include <xen/mm.h>
+#include <xen/vmap.h>
+#include <xen/rbtree.h>
+#include <xen/sched.h>
+#include <xen/sizes.h>
+#include <asm/atomic.h>
+#include <asm/device.h>
+#include <asm/io.h>
+#include <asm/platform.h>
+
+/* Xen: The below defines are redefined within the file. Undef it */
+#undef SCTLR_AFE
+#undef SCTLR_TRE
+#undef SCTLR_M
+#undef TTBCR_EAE
+
+/* Alias to Xen device tree helpers */
+#define device_node dt_device_node
+#define of_phandle_args dt_phandle_args
+#define of_device_id dt_device_match
+#define of_match_node dt_match_node
+#define of_property_read_u32(np, pname, out) (!dt_property_read_u32(np, pname,
out))
+#define of_property_read_bool dt_property_read_bool
+#define of_parse_phandle_with_args dt_parse_phandle_with_args
+
+/* Xen: Helpers to get device MMIO and IRQs */
+struct resource
+{
+ u64 addr;
+ u64 size;
+ unsigned int type;
+};
+
+#define resource_size(res) (res)->size;
+
+#define platform_device dt_device_node
+
+#define IORESOURCE_MEM 0
+#define IORESOURCE_IRQ 1
+
+static struct resource *platform_get_resource(struct platform_device *pdev,
+ unsigned int type,
+ unsigned int num)
+{
+ /*
+ * The resource is only used between 2 calls of platform_get_resource.
+ * It's quite ugly but it's avoid to add too much code in the part
+ * imported from Linux
+ */
+ static struct resource res;
+ int ret = 0;
+
+ res.type = type;
+
+ switch (type) {
+ case IORESOURCE_MEM:
+ ret = dt_device_get_address(pdev, num, &res.addr, &res.size);
+
+ return ((ret) ? NULL : &res);
+
+ case IORESOURCE_IRQ:
+ ret = platform_get_irq(pdev, num);
+ if (ret < 0)
+ return NULL;
+
+ res.addr = ret;
+ res.size = 1;
+
+ return &res;
+
+ default:
+ return NULL;
+ }
+}
+
+/* Alias to Xen IRQ functions */
+#define request_irq(irq, func, flags, name, dev) request_irq(irq, flags, func,
name, dev)
+#define free_irq release_irq
+
+/*
+ * Device logger functions
+ * TODO: Handle PCI
+ */
+#define dev_print(dev, lvl, fmt, ...)
\
+ printk(lvl "smmu: %s: " fmt, dt_node_full_name(dev_to_dt(dev)), ##
__VA_ARGS__)
+
+#define dev_dbg(dev, fmt, ...) dev_print(dev, XENLOG_DEBUG, fmt, ##
__VA_ARGS__)
+#define dev_notice(dev, fmt, ...) dev_print(dev, XENLOG_INFO, fmt, ##
__VA_ARGS__)
+#define dev_warn(dev, fmt, ...) dev_print(dev, XENLOG_WARNING, fmt, ##
__VA_ARGS__)
+#define dev_err(dev, fmt, ...) dev_print(dev, XENLOG_ERR, fmt, ## __VA_ARGS__)
+
+#define dev_err_ratelimited(dev, fmt, ...)
\
+ dev_print(dev, XENLOG_ERR, fmt, ## __VA_ARGS__)
-#include <linux/amba/bus.h>
+#define dev_name(dev) dt_node_full_name(dev_to_dt(dev))
-#include <asm/pgalloc.h>
+/* Alias to Xen allocation helpers */
+#define kfree xfree
+#define kmalloc(size, flags) _xmalloc(size, sizeof(void *))
+#define kzalloc(size, flags) _xzalloc(size, sizeof(void *))
+#define devm_kzalloc(dev, size, flags) _xzalloc(size, sizeof(void *))
+#define kmalloc_array(size, n, flags) _xmalloc_array(size, sizeof(void *), n)
+
+static void __iomem *devm_ioremap_resource(struct device *dev,
+ struct resource *res)
+{
+ void __iomem *ptr;
+
+ if (!res || res->type != IORESOURCE_MEM) {
+ dev_err(dev, "Invalid resource\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ ptr = ioremap_nocache(res->addr, res->size);
+ if (!ptr) {
+ dev_err(dev,
+ "ioremap failed (addr 0x%"PRIx64" size 0x%"PRIx64")\n",
+ res->addr, res->size);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ return ptr;
+}
+
+/* Xen doesn't handle IOMMU fault */
+#define report_iommu_fault(...) 1
+
+#define IOMMU_FAULT_READ 0
+#define IOMMU_FAULT_WRITE 1
+
+/* Xen: misc */
+#define PHYS_MASK_SHIFT PADDR_BITS
+
+#ifdef CONFIG_ARM_64
+# define CONFIG_64BIT
+#endif
+
+#define VA_BITS 0 /* Only used for configuring stage-1
input size */
+
+/* The macro ACCESS_ONCE start to be replaced in Linux in favor of
+ * {READ, WRITE}_ONCE. Rather than introducing in the common code, keep a
+ * version here. We will have to drop it when the SMMU code in Linux will
+ * switch to {READ, WRITE}_ONCE.
+ */
+#define __ACCESS_ONCE(x) ({ \
+ __maybe_unused typeof(x) __var = 0; \
+ (volatile typeof(x) *)&(x); })
+#define ACCESS_ONCE(x) (*__ACCESS_ONCE(x))
+
+/***** Start of SMMU definitions *****/
/* Maximum number of stream IDs assigned to a single device */
#define MAX_MASTER_STREAMIDS MAX_PHANDLE_ARGS
@@ -330,10 +475,14 @@
#define FSYNR0_WNR (1 << 4)
-static int force_stage;
-module_param_named(force_stage, force_stage, int, S_IRUGO | S_IWUSR);
-MODULE_PARM_DESC(force_stage,
- "Force SMMU mappings to be installed at a particular stage of translation. A
value of '1' or '2' forces the corresponding stage. All other values are ignored (i.e. no
stage is forced). Note that selecting a specific stage will disable support for nested
translation.");
+/* Force SMMU mapping to be installed at a particular stage of translation.
+ * A value of '1' or '2' forces the corresponding state. All other values
+ * are ignored (i.e no stage is forced). Note that selecting a specific stage
+ * will disable support for nested translation.
+ *
+ * Xen is only supported stage-2 translation, so force the value to 2.
+ */
+static const int force_stage = 2;
enum arm_smmu_arch_version {
ARM_SMMU_V1 = 1,
@@ -406,7 +555,9 @@ struct arm_smmu_cfg {
u8 cbndx;
u8 irptndx;
u32 cbar;
- pgd_t *pgd;
+
+ /* Xen: Domain associated to this configuration */
+ struct domain *domain;
};
#define INVALID_IRPTNDX 0xff
@@ -426,6 +577,90 @@ struct arm_smmu_domain {
spinlock_t lock;
};
+/* Xen: Dummy iommu_domain */
+struct iommu_domain
+{
+ struct arm_smmu_domain *priv;
+
+ /* Used to link domain contexts for a same domain */
+ struct list_head list;
+};
+
+/* Xen: Describes informations required for a Xen domain */
+struct arm_smmu_xen_domain {
+ spinlock_t lock;
+ /* List of context (i.e iommu_domain) associated to this domain */
+ struct list_head contexts;
+};
+
+/* Xen: Information about each device stored in dev->archdata.iommu */
+struct arm_smmu_xen_device {
+ struct iommu_domain *domain;
+ struct iommu_group *group;
+};
+
+#define dev_archdata(dev) ((struct arm_smmu_xen_device *)dev->archdata.iommu)
+#define dev_iommu_domain(dev) (dev_archdata(dev)->domain)
+#define dev_iommu_group(dev) (dev_archdata(dev)->group)
+
+/* Xen: Dummy iommu_group */
+struct iommu_group
+{
+ struct arm_smmu_master_cfg *cfg;
+
+ atomic_t ref;
+};
+
+static struct iommu_group *iommu_group_alloc(void)
+{
+ struct iommu_group *group = xzalloc(struct iommu_group);
+
+ if (!group)
+ return ERR_PTR(-ENOMEM);
+
+ atomic_set(&group->ref, 1);
+
+ return group;
+}
+
+static void iommu_group_put(struct iommu_group *group)
+{
+ if (atomic_dec_and_test(&group->ref))
+ xfree(group);
+}
+
+static void iommu_group_set_iommudata(struct iommu_group *group,
+ struct arm_smmu_master_cfg *cfg,
+ void (*releasefn)(void *))
+{
+ /* TODO: Store the releasefn for the PCI */
+ ASSERT(releasefn == NULL);
+
+ group->cfg = cfg;
+}
+
+static int iommu_group_add_device(struct iommu_group *group,
+ struct device *dev)
+{
+ dev_iommu_group(dev) = group;
+
+ atomic_inc(&group->ref);
+
+ return 0;
+}
+
+static struct iommu_group *iommu_group_get(struct device *dev)
+{
+ struct iommu_group *group = dev_iommu_group(dev);
+
+ if (group)
+ atomic_inc(&group->ref);
+
+ return group;
+}
+
+#define iommu_group_get_iommudata(group) (group)->cfg
+
static DEFINE_SPINLOCK(arm_smmu_devices_lock);
static LIST_HEAD(arm_smmu_devices);
@@ -455,6 +690,8 @@ static void parse_driver_options(struct arm_smmu_device *smmu)
static struct device_node *dev_get_dev_node(struct device *dev)
{
+ /* Xen: TODO: Add support for PCI */
+#if 0
if (dev_is_pci(dev)) {
struct pci_bus *bus = to_pci_dev(dev)->bus;
@@ -462,7 +699,7 @@ static struct device_node *dev_get_dev_node(struct device *dev)
bus = bus->parent;
return bus->bridge->parent->of_node;
}
-
+#endif
return dev->of_node;
}
@@ -556,6 +793,9 @@ static int register_smmu_master(struct arm_smmu_device *smmu,
master->of_node = masterspec->np;
master->cfg.num_streamids = masterspec->args_count;
+ /* Xen: Let Xen knows that the device is protected by an SMMU */
+ dt_device_set_protected(masterspec->np);
+
for (i = 0; i < master->cfg.num_streamids; ++i) {
u16 streamid = masterspec->args[i];
@@ -651,11 +891,12 @@ static void arm_smmu_tlb_inv_context(struct arm_smmu_domain *smmu_domain)
arm_smmu_tlb_sync(smmu);
}
-static irqreturn_t arm_smmu_context_fault(int irq, void *dev)
+static void arm_smmu_context_fault(int irq, void *dev,
+ struct cpu_user_regs *regs)
{
- int flags, ret;
+ int flags;
u32 fsr, far, fsynr, resume;
- unsigned long iova;
+ paddr_t iova;
struct iommu_domain *domain = dev;
struct arm_smmu_domain *smmu_domain = domain->priv;
struct arm_smmu_cfg *cfg = &smmu_domain->cfg;
@@ -666,7 +907,7 @@ static irqreturn_t arm_smmu_context_fault(int irq, void
*dev)
fsr = readl_relaxed(cb_base + ARM_SMMU_CB_FSR);
if (!(fsr & FSR_FAULT))
- return IRQ_NONE;
+ return;
if (fsr & FSR_IGN)
dev_err_ratelimited(smmu->dev,
@@ -678,19 +919,16 @@ static irqreturn_t arm_smmu_context_fault(int irq, void
*dev)
far = readl_relaxed(cb_base + ARM_SMMU_CB_FAR_LO);
iova = far;
-#ifdef CONFIG_64BIT
+ /* Xen: The fault address maybe higher than 32 bits on arm32 */
far = readl_relaxed(cb_base + ARM_SMMU_CB_FAR_HI);
- iova |= ((unsigned long)far << 32);
-#endif
+ iova |= ((paddr_t)far << 32);
if (!report_iommu_fault(domain, smmu->dev, iova, flags)) {
- ret = IRQ_HANDLED;
resume = RESUME_RETRY;
} else {
dev_err_ratelimited(smmu->dev,
- "Unhandled context fault: iova=0x%08lx, fsynr=0x%x,
cb=%d\n",
+ "Unhandled context fault: iova=0x%"PRIpaddr", fsynr=0x%x,
cb=%d\n",
iova, fsynr, cfg->cbndx);
- ret = IRQ_NONE;
resume = RESUME_TERMINATE;
}
@@ -700,11 +938,10 @@ static irqreturn_t arm_smmu_context_fault(int irq, void *dev)
/* Retry or terminate any stalled transactions */
if (fsr & FSR_SS)
writel_relaxed(resume, cb_base + ARM_SMMU_CB_RESUME);
-
- return ret;
}
-static irqreturn_t arm_smmu_global_fault(int irq, void *dev)
+static void arm_smmu_global_fault(int irq, void *dev,
+ struct cpu_user_regs *regs)
{
u32 gfsr, gfsynr0, gfsynr1, gfsynr2;
struct arm_smmu_device *smmu = dev;
@@ -716,7 +953,7 @@ static irqreturn_t arm_smmu_global_fault(int irq, void *dev)
gfsynr2 = readl_relaxed(gr0_base + ARM_SMMU_GR0_sGFSYNR2);
if (!gfsr)
- return IRQ_NONE;
+ return;
dev_err_ratelimited(smmu->dev,
"Unexpected global fault, this could be serious\n");
@@ -725,9 +962,10 @@ static irqreturn_t arm_smmu_global_fault(int irq, void
*dev)
gfsr, gfsynr0, gfsynr1, gfsynr2);
writel(gfsr, gr0_base + ARM_SMMU_GR0_sGFSR);
- return IRQ_HANDLED;
}
+/* Xen: Page tables are shared with the processor */
+#if 0
static void arm_smmu_flush_pgtable(struct arm_smmu_device *smmu, void *addr,
size_t size)
{
@@ -749,6 +987,7 @@ static void arm_smmu_flush_pgtable(struct arm_smmu_device
*smmu, void *addr,
DMA_TO_DEVICE);
}
}
+#endif
static void arm_smmu_init_context_bank(struct arm_smmu_domain *smmu_domain)
{
@@ -757,6 +996,7 @@ static void arm_smmu_init_context_bank(struct
arm_smmu_domain *smmu_domain)
struct arm_smmu_cfg *cfg = &smmu_domain->cfg;
struct arm_smmu_device *smmu = smmu_domain->smmu;
void __iomem *cb_base, *gr0_base, *gr1_base;
+ paddr_t p2maddr;
gr0_base = ARM_SMMU_GR0(smmu);
gr1_base = ARM_SMMU_GR1(smmu);
@@ -840,11 +1080,16 @@ static void arm_smmu_init_context_bank(struct
arm_smmu_domain *smmu_domain)
}
/* TTBR0 */
- arm_smmu_flush_pgtable(smmu, cfg->pgd,
- PTRS_PER_PGD * sizeof(pgd_t));
- reg = __pa(cfg->pgd);
+ /* Xen: The page table is shared with the P2M code */
+ ASSERT(smmu_domain->cfg.domain != NULL);
+ p2maddr = page_to_maddr(smmu_domain->cfg.domain->arch.p2m.root);
+
+ dev_notice(smmu->dev, "d%u: p2maddr 0x%"PRIpaddr"\n",
+ smmu_domain->cfg.domain->domain_id, p2maddr);
+
+ reg = (p2maddr & ((1ULL << 32) - 1));
writel_relaxed(reg, cb_base + ARM_SMMU_CB_TTBR0_LO);
- reg = (phys_addr_t)__pa(cfg->pgd) >> 32;
+ reg = (p2maddr >> 32);
if (stage1)
reg |= ARM_SMMU_CB_ASID(cfg) << TTBRn_HI_ASID_SHIFT;
writel_relaxed(reg, cb_base + ARM_SMMU_CB_TTBR0_HI);
@@ -886,9 +1131,21 @@ static void arm_smmu_init_context_bank(struct
arm_smmu_domain *smmu_domain)
reg |= (64 - smmu->s1_input_size) << TTBCR_T0SZ_SHIFT;
}
} else {
+#if CONFIG_ARM_32
+ /* Xen: Midway is using 40-bit address space. Though it may
+ * not work on other ARM32 platform with SMMU-v1.
+ * TODO: A quirk may be necessary if we have to support
+ * other ARM32 platform with SMMU-v1.
+ */
+ reg = 0x18 << TTBCR_T0SZ_SHIFT;
+#else
reg = 0;
+#endif
}
+ /* Xen: The attributes to walk the page table should be the same as
+ * VTCR_EL2. Currently doesn't differ from Linux ones.
+ */
reg |= TTBCR_EAE |
(TTBCR_SH_IS << TTBCR_SH0_SHIFT) |
(TTBCR_RGN_WBWA << TTBCR_ORGN0_SHIFT) |
@@ -1031,7 +1288,6 @@ static void arm_smmu_destroy_domain_context(struct
iommu_domain *domain)
static int arm_smmu_domain_init(struct iommu_domain *domain)
{
struct arm_smmu_domain *smmu_domain;
- pgd_t *pgd;
/*
* Allocate the domain and initialise some of its data structures.
@@ -1042,20 +1298,12 @@ static int arm_smmu_domain_init(struct iommu_domain
*domain)
if (!smmu_domain)
return -ENOMEM;
- pgd = kcalloc(PTRS_PER_PGD, sizeof(pgd_t), GFP_KERNEL);
- if (!pgd)
- goto out_free_domain;
- smmu_domain->cfg.pgd = pgd;
-
spin_lock_init(&smmu_domain->lock);
domain->priv = smmu_domain;
return 0;
-
-out_free_domain:
- kfree(smmu_domain);
- return -ENOMEM;
}
+#if 0
static void arm_smmu_free_ptes(pmd_t *pmd)
{
pgtable_t table = pmd_pgtable(*pmd);
@@ -1118,6 +1366,7 @@ static void arm_smmu_free_pgtables(struct arm_smmu_domain
*smmu_domain)
kfree(pgd_base);
}
+#endif
/*
* For a given set N of 2**order different stream IDs (no duplicates
@@ -1259,7 +1508,6 @@ static void arm_smmu_domain_destroy(struct iommu_domain
*domain)
* already been detached.
*/
arm_smmu_destroy_domain_context(domain);
- arm_smmu_free_pgtables(smmu_domain);
kfree(smmu_domain);
}
@@ -1384,11 +1632,12 @@ static void arm_smmu_domain_remove_master(struct arm_smmu_domain *smmu_domain,
/*
* We *must* clear the S2CR first, because freeing the SMR means
* that it can be re-allocated immediately.
+ * Xen: Unlike Linux, any access to non-configured stream will fault.
*/
for (i = 0; i < cfg->num_streamids; ++i) {
u32 idx = cfg->smrs ? cfg->smrs[i].idx : cfg->streamids[i];
- writel_relaxed(S2CR_TYPE_BYPASS,
+ writel_relaxed(S2CR_TYPE_FAULT,
gr0_base + ARM_SMMU_GR0_S2CR(idx));
}
@@ -1408,7 +1657,7 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
return -ENXIO;
}
- if (dev->archdata.iommu) {
+ if (dev_iommu_domain(dev)) {
dev_err(dev, "already attached to IOMMU domain\n");
return -EEXIST;
}
@@ -1440,8 +1689,9 @@ static int arm_smmu_attach_dev(struct iommu_domain
*domain, struct device *dev)
return -ENODEV;
ret = arm_smmu_domain_add_master(smmu_domain, cfg);
+
if (!ret)
- dev->archdata.iommu = domain;
+ dev_iommu_domain(dev) = domain;
return ret;
}
@@ -1454,10 +1704,14 @@ static void arm_smmu_detach_dev(struct iommu_domain *domain, struct device *dev)
if (!cfg)
return;
- dev->archdata.iommu = NULL;
+ dev_iommu_domain(dev) = NULL;
arm_smmu_domain_remove_master(smmu_domain, cfg);
}
+/* Xen: the page table is shared with the processor, therefore helpers to
+ * implement separate is not necessary.
+ */
+#if 0
static bool arm_smmu_pte_is_contiguous_range(unsigned long addr,
unsigned long end)
{
@@ -1746,7 +2000,10 @@ static phys_addr_t arm_smmu_iova_to_phys(struct
iommu_domain *domain,
return __pfn_to_phys(pte_pfn(pte)) | (iova & ~PAGE_MASK);
}
+#endif
+/* Xen: Functions are not used at the moment */
+#if 0
static bool arm_smmu_capable(enum iommu_cap cap)
{
switch (cap) {
@@ -1775,6 +2032,7 @@ static void __arm_smmu_release_pci_iommudata(void *data)
{
kfree(data);
}
+#endif
static int arm_smmu_add_device(struct device *dev)
{
@@ -1784,6 +2042,10 @@ static int arm_smmu_add_device(struct device *dev)
void (*releasefn)(void *) = NULL;
int ret;
+ /* Xen: Check if the device has already been added */
+ if (dev_iommu_group(dev))
+ return -EBUSY;
+
smmu = find_smmu_for_device(dev);
if (!smmu)
return -ENODEV;
@@ -1795,6 +2057,9 @@ static int arm_smmu_add_device(struct device *dev)
}
if (dev_is_pci(dev)) {
+ /* Xen: TODO: Add PCI support */
+ BUG();
+#if 0
struct pci_dev *pdev = to_pci_dev(dev);
cfg = kzalloc(sizeof(*cfg), GFP_KERNEL);
@@ -1811,6 +2076,7 @@ static int arm_smmu_add_device(struct device *dev)
pci_for_each_dma_alias(pdev, __arm_smmu_get_pci_sid,
&cfg->streamids[0]);
releasefn = __arm_smmu_release_pci_iommudata;
+#endif
} else {
struct arm_smmu_master *master;
@@ -1831,6 +2097,8 @@ out_put_group:
return ret;
}
+/* Xen: We don't support remove device for now. Will be useful for PCI */
+#if 0
static void arm_smmu_remove_device(struct device *dev)
{
iommu_group_remove_device(dev);
@@ -1888,6 +2156,7 @@ static const struct iommu_ops arm_smmu_ops = {
ARM_SMMU_PTE_CONT_SIZE |
PAGE_SIZE),
};
+#endif
static void arm_smmu_device_reset(struct arm_smmu_device *smmu)
{
@@ -1903,7 +2172,11 @@ static void arm_smmu_device_reset(struct arm_smmu_device
*smmu)
/* Mark all SMRn as invalid and all S2CRn as bypass */
for (i = 0; i < smmu->num_mapping_groups; ++i) {
writel_relaxed(0, gr0_base + ARM_SMMU_GR0_SMR(i));
- writel_relaxed(S2CR_TYPE_BYPASS,
+ /*
+ * Xen: Unlike Linux, any access to a non-configure stream
+ * will fault by default.
+ */
+ writel_relaxed(S2CR_TYPE_FAULT,
gr0_base + ARM_SMMU_GR0_S2CR(i));
}
@@ -1929,6 +2202,8 @@ static void arm_smmu_device_reset(struct arm_smmu_device *smmu)
/* Enable client access, but bypass when no mapping is found */
reg &= ~(sCR0_CLIENTPD | sCR0_USFCFG);
+ /* Xen: Unlike Linux, generate a fault when no mapping is found */
+ reg |= sCR0_USFCFG;
/* Disable forced broadcasting */
reg &= ~sCR0_FB;
@@ -2039,7 +2314,7 @@ static int arm_smmu_device_cfg_probe(struct
arm_smmu_device *smmu)
smmu->smr_id_mask = sid;
dev_notice(smmu->dev,
- "\tstream matching with %u register groups, mask
0x%x",
+ "\tstream matching with %u register groups, mask
0x%x\n",
smmu->num_mapping_groups, mask);
} else {
smmu->num_mapping_groups = (id >> ID0_NUMSIDB_SHIFT) &
@@ -2074,12 +2349,30 @@ static int arm_smmu_device_cfg_probe(struct
arm_smmu_device *smmu)
size = arm_smmu_id_size_to_bits((id >> ID2_IAS_SHIFT) & ID2_IAS_MASK);
smmu->s1_output_size = min_t(unsigned long, PHYS_MASK_SHIFT, size);
+ /* Xen: Stage-2 input size is not restricted */
+ smmu->s2_input_size = size;
+#if 0
/* Stage-2 input size limited due to pgd allocation (PTRS_PER_PGD) */
#ifdef CONFIG_64BIT
smmu->s2_input_size = min_t(unsigned long, VA_BITS, size);
#else
smmu->s2_input_size = min(32UL, size);
#endif
+#endif
+
+ /*
+ * Xen: SMMU v1: Only 40 bits input address size is supported for
+ * arm32. See arm_smmu_init_context_bank
+ */
+#ifdef CONFIG_ARM_32
+ if ( smmu->version == ARM_SMMU_V1 && smmu->s2_input_size != 40 )
+ {
+ dev_err(smmu->dev,
+ "Stage-2 Input size %ld not supported for SMMUv1\n",
+ smmu->s2_input_size);
+ return -ENODEV;;
+ }
+#endif
/* The stage-2 output mask is also applied for bypass */
size = arm_smmu_id_size_to_bits((id >> ID2_OAS_SHIFT) & ID2_OAS_MASK);
@@ -2124,8 +2417,11 @@ static const struct of_device_id arm_smmu_of_match[] = {
{ .compatible = "arm,mmu-500", .data = (void *)ARM_SMMU_V2 },
{ },
};
-MODULE_DEVICE_TABLE(of, arm_smmu_of_match);
+/*
+ * Xen: We don't have refcount allocated memory so manually free memory when
+ * an error occured.
+ */
static int arm_smmu_device_dt_probe(struct platform_device *pdev)
{
const struct of_device_id *of_id;
@@ -2149,14 +2445,17 @@ static int arm_smmu_device_dt_probe(struct
platform_device *pdev)
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
smmu->base = devm_ioremap_resource(dev, res);
- if (IS_ERR(smmu->base))
- return PTR_ERR(smmu->base);
+ if (IS_ERR(smmu->base)) {
+ err = PTR_ERR(smmu->base);
+ goto out_free;
+ }
smmu->size = resource_size(res);
if (of_property_read_u32(dev->of_node, "#global-interrupts",
&smmu->num_global_irqs)) {
dev_err(dev, "missing #global-interrupts property\n");
- return -ENODEV;
+ err = -ENODEV;
+ goto out_free;
}
num_irqs = 0;
@@ -2169,14 +2468,16 @@ static int arm_smmu_device_dt_probe(struct
platform_device *pdev)
if (!smmu->num_context_irqs) {
dev_err(dev, "found %d interrupts but expected at least %d\n",
num_irqs, smmu->num_global_irqs + 1);
- return -ENODEV;
+ err = -ENODEV;
+ goto out_free;
}
smmu->irqs = devm_kzalloc(dev, sizeof(*smmu->irqs) * num_irqs,
GFP_KERNEL);
if (!smmu->irqs) {
dev_err(dev, "failed to allocate %d irqs\n", num_irqs);
- return -ENOMEM;
+ err = -ENOMEM;
+ goto out_free;
}
for (i = 0; i < num_irqs; ++i) {
@@ -2184,7 +2485,8 @@ static int arm_smmu_device_dt_probe(struct
platform_device *pdev)
if (irq < 0) {
dev_err(dev, "failed to get irq index %d\n", i);
- return -ENODEV;
+ err = -ENODEV;
+ goto out_free;
}
smmu->irqs[i] = irq;
}
@@ -2259,12 +2561,20 @@ out_put_masters:
for (node = rb_first(&smmu->masters); node; node = rb_next(node)) {
struct arm_smmu_master *master
= container_of(node, struct arm_smmu_master, node);
- of_node_put(master->of_node);
+ kfree(master);
}
+out_free:
+ kfree(smmu->irqs);
+ if (!IS_ERR(smmu->base))
+ iounmap(smmu->base);
+ kfree(smmu);
+
return err;
}
+/* Xen: We never remove SMMU */
+#if 0
static int arm_smmu_device_remove(struct platform_device *pdev)
{
int i;
@@ -2359,3 +2669,237 @@ module_exit(arm_smmu_exit);
MODULE_DESCRIPTION("IOMMU API for ARM architected SMMU implementations");
MODULE_AUTHOR("Will Deacon <will.dea...@arm.com>");
MODULE_LICENSE("GPL v2");
+#endif
+
+/* Xen specific function */
+
+static void arm_smmu_iotlb_flush_all(struct domain *d)
+{
+ struct arm_smmu_xen_domain *smmu_domain =
domain_hvm_iommu(d)->arch.priv;
+ struct iommu_domain *cfg;
+
+ spin_lock(&smmu_domain->lock);
+ list_for_each_entry(cfg, &smmu_domain->contexts, list) {
+ /*
+ * Only invalidate the context when SMMU is present.
+ * This is because the context initialization is delayed
+ * until a master has been added.
+ */
+ if (unlikely(!ACCESS_ONCE(cfg->priv->smmu)))
+ continue;
+ arm_smmu_tlb_inv_context(cfg->priv);
+ }
+ spin_unlock(&smmu_domain->lock);
+}
+
+static void arm_smmu_iotlb_flush(struct domain *d, unsigned long gfn,
+ unsigned int page_count)
+{
+ /* ARM SMMU v1 doesn't have flush by VMA and VMID */
+ arm_smmu_iotlb_flush_all(d);
+}
+
+static int arm_smmu_assign_dev(struct domain *d, u8 devfn,
+ struct device *dev)
+{
+ struct iommu_domain *domain;
+ struct arm_smmu_xen_domain *xen_domain;
+ int ret;
+
+ xen_domain = domain_hvm_iommu(d)->arch.priv;
+
+ if (!dev->archdata.iommu) {
+ dev->archdata.iommu = xzalloc(struct arm_smmu_xen_device);
+ if (!dev->archdata.iommu)
+ return -ENOMEM;
+ }
+
+ if (!dev_iommu_group(dev)) {
+ ret = arm_smmu_add_device(dev);
+ if (ret)
+ return ret;
+ }
+
+ /*
+ * TODO: Share the context bank (i.e iommu_domain) when the device is
+ * under the same SMMU as another device assigned to this domain.
+ * Would it useful for PCI
+ */
+ domain = xzalloc(struct iommu_domain);
+ if (!domain)
+ return -ENOMEM;
+
+ ret = arm_smmu_domain_init(domain);
+ if (ret)
+ goto err_dom_init;
+
+ domain->priv->cfg.domain = d;
+
+ ret = arm_smmu_attach_dev(domain, dev);
+ if (ret)
+ goto err_attach_dev;
+
+ spin_lock(&xen_domain->lock);
+ /* Chain the new context to the domain */
+ list_add(&domain->list, &xen_domain->contexts);
+ spin_unlock(&xen_domain->lock);
+
+ return 0;
+
+err_attach_dev:
+ arm_smmu_domain_destroy(domain);
+err_dom_init:
+ xfree(domain);
+
+ return ret;
+}
+
+static int arm_smmu_deassign_dev(struct domain *d, struct device *dev)
+{
+ struct iommu_domain *domain = dev_iommu_domain(dev);
+ struct arm_smmu_xen_domain *xen_domain;
+
+ xen_domain = domain_hvm_iommu(d)->arch.priv;
+
+ if (!domain || domain->priv->cfg.domain != d) {
+ dev_err(dev, " not attached to domain %d\n", d->domain_id);
+ return -ESRCH;
+ }
+
+ arm_smmu_detach_dev(domain, dev);
+
+ spin_lock(&xen_domain->lock);
+ list_del(&domain->list);
+ spin_unlock(&xen_domain->lock);
+
+ arm_smmu_domain_destroy(domain);
+ xfree(domain);
+
+ return 0;
+}
+
+static int arm_smmu_reassign_dev(struct domain *s, struct domain *t,
+ u8 devfn, struct device *dev)
+{
+ int ret = 0;
+
+ /* Don't allow remapping on other domain than hwdom */
+ if (t != hardware_domain)
+ return -EPERM;
+
+ if (t == s)
+ return 0;
+
+ ret = arm_smmu_deassign_dev(s, dev);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static int arm_smmu_iommu_domain_init(struct domain *d)
+{
+ struct arm_smmu_xen_domain *xen_domain;
+
+ xen_domain = xzalloc(struct arm_smmu_xen_domain);
+ if ( !xen_domain )
+ return -ENOMEM;
+
+ spin_lock_init(&xen_domain->lock);
+ INIT_LIST_HEAD(&xen_domain->contexts);
+
+ domain_hvm_iommu(d)->arch.priv = xen_domain;
+
+ return 0;
+}
+
+static void __hwdom_init arm_smmu_iommu_hwdom_init(struct domain *d)
+{
+}
+
+static void arm_smmu_iommu_domain_teardown(struct domain *d)
+{
+ struct arm_smmu_xen_domain *xen_domain = domain_hvm_iommu(d)->arch.priv;
+
+ ASSERT(list_empty(&xen_domain->contexts));
+ xfree(xen_domain);
+}
+
+
+static int arm_smmu_map_page(struct domain *d, unsigned long gfn,
+ unsigned long mfn, unsigned int flags)
+{
+ p2m_type_t t;
+
+ /*
+ * Grant mappings can be used for DMA requests. The dev_bus_addr
+ * returned by the hypercall is the MFN (not the IPA). For device
+ * protected by an IOMMU, Xen needs to add a 1:1 mapping in the domain
+ * p2m to allow DMA request to work.
+ * This is only valid when the domain is directed mapped. Hence this
+ * function should only be used by gnttab code with gfn == mfn.
+ */
+ BUG_ON(!is_domain_direct_mapped(d));
+ BUG_ON(mfn != gfn);
+
+ /* We only support readable and writable flags */
+ if (!(flags & (IOMMUF_readable | IOMMUF_writable)))
+ return -EINVAL;
+
+ t = (flags & IOMMUF_writable) ? p2m_iommu_map_rw : p2m_iommu_map_ro;
+
+ /*
+ * The function guest_physmap_add_entry replaces the current mapping
+ * if there is already one...
+ */
+ return guest_physmap_add_entry(d, gfn, mfn, 0, t);
+}
+
+static int arm_smmu_unmap_page(struct domain *d, unsigned long gfn)
+{
+ /*
+ * This function should only be used by gnttab code when the domain
+ * is direct mapped
+ */
+ if ( !is_domain_direct_mapped(d) )
+ return -EINVAL;
+
+ guest_physmap_remove_page(d, gfn, gfn, 0);
+
+ return 0;
+}
+
+static const struct iommu_ops arm_smmu_iommu_ops = {
+ .init = arm_smmu_iommu_domain_init,
+ .hwdom_init = arm_smmu_iommu_hwdom_init,
+ .teardown = arm_smmu_iommu_domain_teardown,
+ .iotlb_flush = arm_smmu_iotlb_flush,
+ .iotlb_flush_all = arm_smmu_iotlb_flush_all,
+ .assign_device = arm_smmu_assign_dev,
+ .reassign_device = arm_smmu_reassign_dev,
+ .map_page = arm_smmu_map_page,
+ .unmap_page = arm_smmu_unmap_page,
+};
+
+static __init int arm_smmu_dt_init(struct dt_device_node *dev,
+ const void *data)
+{
+ int rc;
+
+ /*
+ * Even if the device can't be initialized, we don't want to
+ * give the SMMU device to dom0.
+ */
+ dt_device_set_used_by(dev, DOMID_XEN);
+
+ rc = arm_smmu_device_dt_probe(dev);
+ if ( !rc )
+ iommu_set_ops(&arm_smmu_iommu_ops);
+
+ return rc;
+}
+
+DT_DEVICE_START(smmu, "ARM SMMU", DEVICE_IOMMU)
+ .dt_match = arm_smmu_of_match,
+ .init = arm_smmu_dt_init,
+DT_DEVICE_END
