2013-07-26 11:30:24

by Cho KyongHo

[permalink] [raw]
Subject: [PATCH v8 10/12] iommu/exynos: add bus notifier for registering System MMU

When a device driver is registered, all constructs to handle System MMU
is prepared by bus notifier call.

Signed-off-by: Cho KyongHo <[email protected]>
---
drivers/iommu/exynos-iommu.c | 708 ++++++++++++++++++++++++++++++++---------
1 files changed, 552 insertions(+), 156 deletions(-)

diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index f9853fe..c62c244 100644
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -27,6 +27,9 @@
#include <linux/memblock.h>
#include <linux/export.h>
#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/pm_domain.h>
+#include <linux/notifier.h>

#include <asm/cacheflush.h>
#include <asm/pgtable.h>
@@ -80,7 +83,13 @@
#define CTRL_BLOCK 0x7
#define CTRL_DISABLE 0x0

+#define CFG_LRU 0x1
+#define CFG_QOS(n) ((n & 0xF) << 7)
+#define CFG_MASK 0x0150FFFF /* Selecting bit 0-15, 20, 22 and 24 */
+#define CFG_ACGEN (1 << 24) /* System MMU 3.3 only */
+#define CFG_SYSSEL (1 << 22) /* System MMU 3.2 only */
#define CFG_FLPDCACHE (1 << 20) /* System MMU 3.2+ only */
+#define CFG_SHAREABLE (1 << 12) /* System MMU 3.x only */

#define REG_MMU_CTRL 0x000
#define REG_MMU_CFG 0x004
@@ -154,6 +163,14 @@ static char *sysmmu_fault_name[SYSMMU_FAULTS_NUM] = {
"UNKNOWN FAULT"
};

+struct exynos_iommu_client {
+ struct list_head node; /* entry of exynos_iommu_domain.clients */
+ struct device *dev;
+ spinlock_t lock;
+ int num_sysmmu;
+ struct device *sysmmu[0];
+};
+
struct exynos_iommu_domain {
struct list_head clients; /* list of sysmmu_drvdata.node */
unsigned long *pgtable; /* lv1 page table, 16KB */
@@ -165,12 +182,14 @@ struct exynos_iommu_domain {
struct sysmmu_drvdata {
struct list_head node; /* entry of exynos_iommu_domain.clients */
struct device *sysmmu; /* System MMU's device descriptor */
- struct device *dev; /* Owner of system MMU */
+ struct device *master; /* Owner of system MMU */
int nsfrs;
struct clk *clk;
+ struct clk *clk_master;
int activations;
rwlock_t lock;
struct iommu_domain *domain;
+ bool runtime_active;
unsigned long pgtable;
void __iomem *sfrbases[0];
};
@@ -245,7 +264,6 @@ static void __sysmmu_tlb_invalidate_entry(void __iomem *sfrbase,
static void __sysmmu_set_ptbase(void __iomem *sfrbase,
unsigned long pgd)
{
- __raw_writel(0x1, sfrbase + REG_MMU_CFG); /* 16KB LV1, LRU */
__raw_writel(pgd, sfrbase + REG_PT_BASE_ADDR);

__sysmmu_tlb_invalidate(sfrbase);
@@ -273,6 +291,7 @@ void exynos_sysmmu_set_prefbuf(struct device *dev,
if (!is_sysmmu_active(data))
goto finish;

+ clk_enable(data->clk_master);
for (i = 0; i < data->nsfrs; i++) {
if ((readl(data->sfrbases[i] + REG_MMU_VERSION) >> 28) == 3) {
if (!sysmmu_block(data->sfrbases[i]))
@@ -298,6 +317,7 @@ void exynos_sysmmu_set_prefbuf(struct device *dev,
sysmmu_unblock(data->sfrbases[i]);
}
}
+ clk_disable(data->clk_master);
finish:
read_unlock_irqrestore(&data->lock, flags);
}
@@ -331,12 +351,13 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
{
/* SYSMMU is in blocked when interrupt occurred. */
struct sysmmu_drvdata *data = dev_id;
+ struct exynos_iommu_client *client = NULL;
enum exynos_sysmmu_inttype itype;
unsigned long addr = -1;
-
int i, ret = -ENOSYS;

- read_lock(&data->lock);
+ if (data->master)
+ client = data->master->archdata.iommu;

WARN_ON(!is_sysmmu_active(data));

@@ -348,6 +369,10 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
break;
}

+ if (client)
+ spin_lock(&client->lock);
+ read_lock(&data->lock);
+
if (i == data->nsfrs) {
itype = SYSMMU_FAULT_UNKNOWN;
} else {
@@ -361,7 +386,7 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
}

if (data->domain)
- ret = report_iommu_fault(data->domain, data->dev,
+ ret = report_iommu_fault(data->domain, data->master,
addr, itype);

if (!ret && (itype != SYSMMU_FAULT_UNKNOWN))
@@ -378,177 +403,251 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
sysmmu_unblock(data->sfrbases[i]);

read_unlock(&data->lock);
+ if (client)
+ spin_unlock(&client->lock);

return IRQ_HANDLED;
}

-static bool __exynos_sysmmu_disable(struct sysmmu_drvdata *data)
+static void __sysmmu_disable_nocount(struct sysmmu_drvdata *data)
{
- unsigned long flags;
- bool disabled = false;
int i;

- write_lock_irqsave(&data->lock, flags);
+ clk_enable(data->clk_master);
+ for (i = 0; i < data->nsfrs; i++) {
+ __raw_writel(CTRL_DISABLE,
+ data->sfrbases[i] + REG_MMU_CTRL);
+ __raw_writel(0, data->sfrbases[i] + REG_MMU_CFG);
+ }

- if (!set_sysmmu_inactive(data))
- goto finish;
+ clk_disable(data->clk);
+ clk_disable(data->clk_master);
+}

- for (i = 0; i < data->nsfrs; i++)
- __raw_writel(CTRL_DISABLE, data->sfrbases[i] + REG_MMU_CTRL);
+static bool __sysmmu_disable(struct sysmmu_drvdata *data)
+{
+ bool disabled;
+ unsigned long flags;

- if (data->clk)
- clk_disable(data->clk);
+ write_lock_irqsave(&data->lock, flags);

- disabled = true;
- data->pgtable = 0;
- data->domain = NULL;
-finish:
- write_unlock_irqrestore(&data->lock, flags);
+ disabled = set_sysmmu_inactive(data);
+
+ if (disabled) {
+ data->pgtable = 0;
+ data->domain = NULL;
+
+ if (data->runtime_active)
+ __sysmmu_disable_nocount(data);

- if (disabled)
dev_dbg(data->sysmmu, "Disabled\n");
- else
- dev_dbg(data->sysmmu, "%d times left to be disabled\n",
+ } else {
+ dev_dbg(data->sysmmu, "%d times left to disable\n",
data->activations);
+ }
+
+ write_unlock_irqrestore(&data->lock, flags);

return disabled;
}

-/* __exynos_sysmmu_enable: Enables System MMU
- *
- * returns -error if an error occurred and System MMU is not enabled,
- * 0 if the System MMU has been just enabled and 1 if System MMU was already
- * enabled before.
- */
-static int __exynos_sysmmu_enable(struct sysmmu_drvdata *data,
+
+static void __sysmmu_init_config(struct sysmmu_drvdata *data, int idx)
+{
+ unsigned long cfg = CFG_LRU | CFG_QOS(15);
+ int maj, min = 0;
+
+ maj = __sysmmu_version(data, idx, &min);
+ if (maj == 3) {
+ if (min > 1) {
+ cfg |= CFG_FLPDCACHE;
+ cfg |= (min == 2) ? CFG_SYSSEL : CFG_ACGEN;
+ }
+ }
+
+ __raw_writel(cfg, data->sfrbases[idx] + REG_MMU_CFG);
+}
+
+static void __sysmmu_enable_nocount(struct sysmmu_drvdata *data)
+{
+ int i;
+
+ clk_enable(data->clk_master);
+ clk_enable(data->clk);
+
+ for (i = 0; i < data->nsfrs; i++) {
+ __raw_writel(CTRL_BLOCK, data->sfrbases[i] + REG_MMU_CTRL);
+
+ __sysmmu_init_config(data, i);
+
+ __sysmmu_set_ptbase(data->sfrbases[i], data->pgtable);
+
+ __raw_writel(CTRL_ENABLE, data->sfrbases[i] + REG_MMU_CTRL);
+ }
+ clk_disable(data->clk_master);
+}
+
+static int __sysmmu_enable(struct sysmmu_drvdata *data,
unsigned long pgtable, struct iommu_domain *domain)
{
- int i, ret = 0;
+ int ret = 0;
unsigned long flags;

write_lock_irqsave(&data->lock, flags);
+ if (set_sysmmu_active(data)) {
+ data->pgtable = pgtable;
+ data->domain = domain;

- if (!set_sysmmu_active(data)) {
- if (WARN_ON(pgtable != data->pgtable)) {
- ret = -EBUSY;
- set_sysmmu_inactive(data);
- } else {
- ret = 1;
- }
+ if (data->runtime_active)
+ __sysmmu_enable_nocount(data);

- dev_dbg(data->sysmmu, "Already enabled\n");
- goto finish;
+ dev_dbg(data->sysmmu, "Enabled\n");
+ } else {
+ ret = (pgtable == data->pgtable) ? 1 : -EBUSY;
+
+ dev_dbg(data->sysmmu, "already enabled\n");
}

- if (data->clk)
- clk_enable(data->clk);
+ if (WARN_ON(ret < 0))
+ set_sysmmu_inactive(data); /* decrement count */

- data->pgtable = pgtable;
+ write_unlock_irqrestore(&data->lock, flags);

- for (i = 0; i < data->nsfrs; i++) {
- unsigned int min;
+ return ret;
+}

- __sysmmu_set_ptbase(data->sfrbases[i], pgtable);
+/* __exynos_sysmmu_enable: Enables System MMU
+ *
+ * returns -error if an error occurred and System MMU is not enabled,
+ * 0 if the System MMU has been just enabled and 1 if System MMU was already
+ * enabled before.
+ */
+static int __exynos_sysmmu_enable(struct device *dev, unsigned long pgtable,
+ struct iommu_domain *domain)
+{
+ int ret = 0;
+ unsigned long flags;
+ struct exynos_iommu_client *client = dev->archdata.iommu;
+ int i;

- if ((__sysmmu_version(data, i, &min) == 3) && (min > 1)) {
- unsigned long cfg;
- cfg = __raw_readl(data->sfrbases[i] + REG_MMU_CFG);
- __raw_writel(cfg | CFG_FLPDCACHE,
- data->sfrbases[i] + REG_MMU_CFG);
- }
+ if (WARN_ON(!client))
+ return -ENODEV;

- __raw_writel(CTRL_ENABLE, data->sfrbases[i] + REG_MMU_CTRL);
- }
+ spin_lock_irqsave(&client->lock, flags);

- data->domain = domain;
+ for (i = 0; i < client->num_sysmmu; i++) {
+ struct sysmmu_drvdata *data =
+ dev_get_drvdata(client->sysmmu[i]);
+ ret = __sysmmu_enable(data, pgtable, domain);
+ if (ret < 0) {
+ int j;
+ for (j = 0; j < i; j++)
+ __sysmmu_disable(data);
+ break;
+ } else {
+ data->master = dev;
+ }
+ }

- dev_dbg(data->sysmmu, "Enabled\n");
-finish:
- write_unlock_irqrestore(&data->lock, flags);
+ spin_unlock_irqrestore(&client->lock, flags);

return ret;
}

int exynos_sysmmu_enable(struct device *dev, unsigned long pgtable)
{
- struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
int ret;

BUG_ON(!memblock_is_memory(pgtable));

- ret = pm_runtime_get_sync(data->sysmmu);
- if (ret < 0) {
- dev_dbg(data->sysmmu, "Failed to enable\n");
- return ret;
- }
-
- ret = __exynos_sysmmu_enable(data, pgtable, NULL);
- if (WARN_ON(ret < 0)) {
- pm_runtime_put(data->sysmmu);
- dev_err(data->sysmmu,
- "Already enabled with page table %#lx\n",
- data->pgtable);
- } else {
- data->dev = dev;
- }
+ ret = __exynos_sysmmu_enable(dev, pgtable, NULL);

return ret;
}

static bool exynos_sysmmu_disable(struct device *dev)
{
- struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
- bool disabled;
+ unsigned long flags;
+ bool disabled = true;
+ struct exynos_iommu_client *client = dev->archdata.iommu;
+ int i;

- disabled = __exynos_sysmmu_disable(data);
- pm_runtime_put(data->sysmmu);
+ if (WARN_ON(!client))
+ return true;
+
+ spin_lock_irqsave(&client->lock, flags);
+
+ /* Every call to __sysmmu_disable() must return same result */
+ for (i = 0; i < client->num_sysmmu; i++) {
+ struct sysmmu_drvdata *data =
+ dev_get_drvdata(client->sysmmu[i]);
+ disabled = __sysmmu_disable(data);
+ if (disabled)
+ data->master = NULL;
+ }
+
+ spin_unlock_irqrestore(&client->lock, flags);

return disabled;
}

static void sysmmu_tlb_invalidate_entry(struct device *dev, unsigned long iova)
{
- unsigned long flags;
- struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
+ struct exynos_iommu_client *client = dev->archdata.iommu;
+ int i;

- read_lock_irqsave(&data->lock, flags);
+ for (i = 0; i < client->num_sysmmu; i++) {
+ unsigned long flags;
+ struct sysmmu_drvdata *data;

- if (is_sysmmu_active(data)) {
- int i;
- for (i = 0; i < data->nsfrs; i++) {
- if (sysmmu_block(data->sfrbases[i])) {
+ data = dev_get_drvdata(client->sysmmu[i]);
+
+ read_lock_irqsave(&data->lock, flags);
+ if (is_sysmmu_active(data) && data->runtime_active) {
+ int i;
+ clk_enable(data->clk_master);
+ for (i = 0; i < data->nsfrs; i++)
__sysmmu_tlb_invalidate_entry(
data->sfrbases[i], iova);
- sysmmu_unblock(data->sfrbases[i]);
- }
+ clk_disable(data->clk_master);
+ } else {
+ dev_dbg(dev,
+ "disabled. Skipping TLB invalidation @ %#lx\n",
+ iova);
}
- } else {
- dev_dbg(data->sysmmu, "Disabled. Skipping invalidating TLB.\n");
+ read_unlock_irqrestore(&data->lock, flags);
}
-
- read_unlock_irqrestore(&data->lock, flags);
}

void exynos_sysmmu_tlb_invalidate(struct device *dev)
{
- unsigned long flags;
- struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
-
- read_lock_irqsave(&data->lock, flags);
+ struct exynos_iommu_client *client = dev->archdata.iommu;
+ int i;

- if (is_sysmmu_active(data)) {
- int i;
- for (i = 0; i < data->nsfrs; i++) {
- if (sysmmu_block(data->sfrbases[i])) {
- __sysmmu_tlb_invalidate(data->sfrbases[i]);
- sysmmu_unblock(data->sfrbases[i]);
+ for (i = 0; i < client->num_sysmmu; i++) {
+ unsigned long flags;
+ struct sysmmu_drvdata *data;
+
+ data = dev_get_drvdata(client->sysmmu[i]);
+
+ read_lock_irqsave(&data->lock, flags);
+ if (is_sysmmu_active(data) &&
+ data->runtime_active) {
+ int i;
+ for (i = 0; i < data->nsfrs; i++) {
+ clk_enable(data->clk_master);
+ if (sysmmu_block(data->sfrbases[i])) {
+ __sysmmu_tlb_invalidate(
+ data->sfrbases[i]);
+ sysmmu_unblock(data->sfrbases[i]);
+ }
+ clk_disable(data->clk_master);
}
+ } else {
+ dev_dbg(dev, "disabled. Skipping TLB invalidation\n");
}
- } else {
- dev_dbg(data->sysmmu, "Disabled. Skipping invalidating TLB.\n");
+ read_unlock_irqrestore(&data->lock, flags);
}
-
- read_unlock_irqrestore(&data->lock, flags);
}

static int __init exynos_sysmmu_probe(struct platform_device *pdev)
@@ -610,12 +709,32 @@ static int __init exynos_sysmmu_probe(struct platform_device *pdev)
pm_runtime_enable(dev);

data->sysmmu = dev;
+
data->clk = devm_clk_get(dev, "sysmmu");
if (IS_ERR(data->clk)) {
dev_info(dev, "No gate clock found!\n");
data->clk = NULL;
}

+ ret = clk_prepare(data->clk);
+ if (ret) {
+ dev_err(dev, "Failed to prepare clk\n");
+ return ret;
+ }
+
+ data->clk_master = devm_clk_get(dev, "master");
+ if (IS_ERR(data->clk_master))
+ data->clk_master = NULL;
+
+ ret = clk_prepare(data->clk_master);
+ if (ret) {
+ clk_unprepare(data->clk);
+ dev_err(dev, "Failed to prepare master's clk\n");
+ return ret;
+ }
+
+ data->runtime_active = !pm_runtime_enabled(dev);
+
rwlock_init(&data->lock);
INIT_LIST_HEAD(&data->node);

@@ -625,6 +744,34 @@ static int __init exynos_sysmmu_probe(struct platform_device *pdev)
return ret;
}

+#ifdef CONFIG_PM_SLEEP
+static int sysmmu_suspend(struct device *dev)
+{
+ struct sysmmu_drvdata *data = dev_get_drvdata(dev);
+ unsigned long flags;
+ read_lock_irqsave(&data->lock, flags);
+ if (is_sysmmu_active(data) &&
+ (!pm_runtime_enabled(dev) || data->runtime_active))
+ __sysmmu_disable_nocount(data);
+ read_unlock_irqrestore(&data->lock, flags);
+ return 0;
+}
+
+static int sysmmu_resume(struct device *dev)
+{
+ struct sysmmu_drvdata *data = dev_get_drvdata(dev);
+ unsigned long flags;
+ read_lock_irqsave(&data->lock, flags);
+ if (is_sysmmu_active(data) &&
+ (!pm_runtime_enabled(dev) || data->runtime_active))
+ __sysmmu_enable_nocount(data);
+ read_unlock_irqrestore(&data->lock, flags);
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(sysmmu_pm_ops, sysmmu_suspend, sysmmu_resume);
+
#ifdef CONFIG_OF
static struct of_device_id sysmmu_of_match[] __initconst = {
{ .compatible = "samsung,exynos4210-sysmmu", },
@@ -637,6 +784,7 @@ static struct platform_driver exynos_sysmmu_driver __refdata = {
.driver = {
.owner = THIS_MODULE,
.name = "exynos-sysmmu",
+ .pm = &sysmmu_pm_ops,
.of_match_table = of_match_ptr(sysmmu_of_match),
}
};
@@ -689,7 +837,7 @@ err_pgtable:
static void exynos_iommu_domain_destroy(struct iommu_domain *domain)
{
struct exynos_iommu_domain *priv = domain->priv;
- struct sysmmu_drvdata *data;
+ struct exynos_iommu_client *client;
unsigned long flags;
int i;

@@ -697,11 +845,14 @@ static void exynos_iommu_domain_destroy(struct iommu_domain *domain)

spin_lock_irqsave(&priv->lock, flags);

- list_for_each_entry(data, &priv->clients, node) {
- while (!exynos_sysmmu_disable(data->dev))
+ list_for_each_entry(client, &priv->clients, node) {
+ while (!exynos_sysmmu_disable(client->dev))
; /* until System MMU is actually disabled */
}

+ while (!list_empty(&priv->clients))
+ list_del_init(priv->clients.next);
+
spin_unlock_irqrestore(&priv->lock, flags);

for (i = 0; i < NUM_LV1ENTRIES; i++)
@@ -718,41 +869,26 @@ static void exynos_iommu_domain_destroy(struct iommu_domain *domain)
static int exynos_iommu_attach_device(struct iommu_domain *domain,
struct device *dev)
{
- struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
+ struct exynos_iommu_client *client = dev->archdata.iommu;
struct exynos_iommu_domain *priv = domain->priv;
unsigned long flags;
int ret;

- ret = pm_runtime_get_sync(data->sysmmu);
- if (ret < 0)
- return ret;
-
- ret = 0;
-
spin_lock_irqsave(&priv->lock, flags);

- ret = __exynos_sysmmu_enable(data, __pa(priv->pgtable), domain);
-
- if (ret == 0) {
- /* 'data->node' must not be appeared in priv->clients */
- BUG_ON(!list_empty(&data->node));
- data->dev = dev;
- list_add_tail(&data->node, &priv->clients);
- }
+ ret = __exynos_sysmmu_enable(dev, __pa(priv->pgtable), domain);
+ if (ret == 0)
+ list_add_tail(&client->node, &priv->clients);

spin_unlock_irqrestore(&priv->lock, flags);

- if (ret < 0) {
+ if (ret < 0)
dev_err(dev, "%s: Failed to attach IOMMU with pgtable %#lx\n",
__func__, __pa(priv->pgtable));
- pm_runtime_put(data->sysmmu);
- } else if (ret > 0) {
- dev_dbg(dev, "%s: IOMMU with pgtable 0x%lx already attached\n",
- __func__, __pa(priv->pgtable));
- } else {
- dev_dbg(dev, "%s: Attached new IOMMU with pgtable 0x%lx\n",
- __func__, __pa(priv->pgtable));
- }
+ else
+ dev_dbg(dev, "%s: Attached IOMMU with pgtable 0x%lx%s\n",
+ __func__, __pa(priv->pgtable),
+ (ret == 0) ? "" : ", again");

return ret;
}
@@ -760,39 +896,27 @@ static int exynos_iommu_attach_device(struct iommu_domain *domain,
static void exynos_iommu_detach_device(struct iommu_domain *domain,
struct device *dev)
{
- struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
+ struct exynos_iommu_client *client = NULL;
struct exynos_iommu_domain *priv = domain->priv;
- struct list_head *pos;
unsigned long flags;
- bool found = false;

spin_lock_irqsave(&priv->lock, flags);

- list_for_each(pos, &priv->clients) {
- if (list_entry(pos, struct sysmmu_drvdata, node) == data) {
- found = true;
+ list_for_each_entry(client, &priv->clients, node) {
+ if (client == dev->archdata.iommu) {
+ if (exynos_sysmmu_disable(dev))
+ list_del_init(&client->node);
break;
}
}

- if (!found)
- goto finish;
+ spin_unlock_irqrestore(&priv->lock, flags);

- if (__exynos_sysmmu_disable(data)) {
+ if (client == dev->archdata.iommu)
dev_dbg(dev, "%s: Detached IOMMU with pgtable %#lx\n",
__func__, __pa(priv->pgtable));
- list_del_init(&data->node);
-
- } else {
- dev_dbg(dev, "%s: Detaching IOMMU with pgtable %#lx delayed",
- __func__, __pa(priv->pgtable));
- }
-
-finish:
- spin_unlock_irqrestore(&priv->lock, flags);
-
- if (found)
- pm_runtime_put(data->sysmmu);
+ else
+ dev_dbg(dev, "%s: No IOMMU is attached\n", __func__);
}

static unsigned long *alloc_lv2entry(unsigned long *sent, unsigned long iova,
@@ -914,7 +1038,7 @@ static size_t exynos_iommu_unmap(struct iommu_domain *domain,
unsigned long iova, size_t size)
{
struct exynos_iommu_domain *priv = domain->priv;
- struct sysmmu_drvdata *data;
+ struct exynos_iommu_client *client;
unsigned long flags;
unsigned long *ent;
size_t err_pgsize;
@@ -975,8 +1099,8 @@ done:
spin_unlock_irqrestore(&priv->pgtablelock, flags);

spin_lock_irqsave(&priv->lock, flags);
- list_for_each_entry(data, &priv->clients, node)
- sysmmu_tlb_invalidate_entry(data->dev, iova);
+ list_for_each_entry(client, &priv->clients, node)
+ sysmmu_tlb_invalidate_entry(client->dev, iova);
spin_unlock_irqrestore(&priv->lock, flags);

return size;
@@ -1055,3 +1179,275 @@ static int __init exynos_iommu_init(void)
return ret;
}
subsys_initcall(exynos_iommu_init);
+
+#ifdef CONFIG_PM_SLEEP
+static int sysmmu_pm_genpd_suspend(struct device *dev)
+{
+ struct exynos_iommu_client *client = dev->archdata.iommu;
+ int ret = 0;
+ int i;
+
+ for (i = 0; i < client->num_sysmmu; i++) {
+ ret = pm_generic_suspend(client->sysmmu[i]);
+ if (ret)
+ break;
+ }
+
+ if (!ret)
+ ret = pm_generic_suspend(dev);
+
+ if (ret) {
+ int j;
+
+ for (j = 0; j < i; j++)
+ pm_generic_resume(client->sysmmu[j]);
+ }
+
+ return ret;
+}
+
+static int sysmmu_pm_genpd_resume(struct device *dev)
+{
+ struct exynos_iommu_client *client = dev->archdata.iommu;
+ int ret = 0;
+ int i;
+
+ for (i = 0; i < client->num_sysmmu; i++) {
+ ret = pm_generic_resume(client->sysmmu[i]);
+ if (ret)
+ break;
+ }
+
+ if (!ret)
+ ret = pm_generic_resume(dev);
+
+ if (ret) {
+ int j;
+
+ for (j = 0; j < i; j++)
+ pm_generic_suspend(client->sysmmu[j]);
+ }
+
+ return ret;
+}
+#endif
+
+#ifdef CONFIG_PM_RUNTIME
+static void sysmmu_restore_state(struct device *sysmmu)
+{
+ struct sysmmu_drvdata *data = dev_get_drvdata(sysmmu);
+ unsigned long flags;
+
+ spin_lock_irqsave(&data->lock, flags);
+ data->runtime_active = true;
+ if (is_sysmmu_active(data))
+ __sysmmu_enable_nocount(data);
+ spin_unlock_irqrestore(&data->lock, flags);
+}
+
+static void sysmmu_save_state(struct device *sysmmu)
+{
+ struct sysmmu_drvdata *data = dev_get_drvdata(sysmmu);
+ unsigned long flags;
+
+ spin_lock_irqsave(&data->lock, flags);
+ if (is_sysmmu_active(data))
+ __sysmmu_disable_nocount(data);
+ data->runtime_active = false;
+ spin_unlock_irqrestore(&data->lock, flags);
+}
+
+static int sysmmu_pm_genpd_save_state(struct device *dev)
+{
+ struct exynos_iommu_client *client = dev->archdata.iommu;
+ int (*cb)(struct device *__dev);
+ int i;
+
+ if (dev->type && dev->type->pm)
+ cb = dev->type->pm->runtime_suspend;
+ else if (dev->class && dev->class->pm)
+ cb = dev->class->pm->runtime_suspend;
+ else if (dev->bus && dev->bus->pm)
+ cb = dev->bus->pm->runtime_suspend;
+ else
+ cb = NULL;
+
+ if (!cb && dev->driver && dev->driver->pm)
+ cb = dev->driver->pm->runtime_suspend;
+
+ if (cb) {
+ int ret;
+
+ ret = cb(dev);
+ if (ret)
+ return ret;
+ }
+
+ for (i = 0; i < client->num_sysmmu; i++)
+ sysmmu_save_state(client->sysmmu[i]);
+
+ return 0;
+}
+
+static int sysmmu_pm_genpd_restore_state(struct device *dev)
+{
+ struct exynos_iommu_client *client = dev->archdata.iommu;
+ int (*cb)(struct device *__dev);
+ int i;
+
+ if (dev->type && dev->type->pm)
+ cb = dev->type->pm->runtime_resume;
+ else if (dev->class && dev->class->pm)
+ cb = dev->class->pm->runtime_resume;
+ else if (dev->bus && dev->bus->pm)
+ cb = dev->bus->pm->runtime_resume;
+ else
+ cb = NULL;
+
+ if (!cb && dev->driver && dev->driver->pm)
+ cb = dev->driver->pm->runtime_resume;
+
+ for (i = 0; i < client->num_sysmmu; i++)
+ sysmmu_restore_state(client->sysmmu[i]);
+
+ if (cb) {
+ int ret;
+ ret = cb(dev);
+ if (ret) {
+ for (i = 0; i < client->num_sysmmu; i++)
+ sysmmu_save_state(client->sysmmu[i]);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+#endif
+
+#ifdef CONFIG_PM_GENERIC_DOMAINS
+struct gpd_dev_ops sysmmu_devpm_ops = {
+#ifdef CONFIG_PM_RUNTIME
+ .save_state = &sysmmu_pm_genpd_save_state,
+ .restore_state = &sysmmu_pm_genpd_restore_state,
+#endif
+#ifdef CONFIG_PM_SLEEP
+ .suspend = &sysmmu_pm_genpd_suspend,
+ .resume = &sysmmu_pm_genpd_resume,
+#endif
+};
+#endif /* CONFIG_PM_GENERIC_DOMAINS */
+
+static int sysmmu_hook_driver_register(struct notifier_block *nb,
+ unsigned long val,
+ void *p)
+{
+ struct device *dev = p;
+
+ switch (val) {
+ case BUS_NOTIFY_BIND_DRIVER:
+ {
+ int i = 0;
+ int size = 0;
+ const __be32 *phandle;
+ struct exynos_iommu_client *client;
+
+ phandle = of_get_property(dev->of_node, "iommu", &size);
+ if (!phandle)
+ break;
+
+ size = size / sizeof(*phandle); /* number of elements */
+
+ client = devm_kzalloc(dev, sizeof(*client) * size, GFP_KERNEL);
+ if (!client) {
+ dev_err(dev, "No Memory for exynos_iommu_client\n");
+ return -ENOMEM;
+ }
+
+ client->num_sysmmu = size;
+ client->dev = dev;
+ INIT_LIST_HEAD(&client->node);
+ spin_lock_init(&client->lock);
+
+ for (i = 0; i < size; i++) {
+ struct device_node *np;
+ struct platform_device *sysmmu;
+
+ /* this always success: see above of_find_property() */
+ np = of_parse_phandle(dev->of_node, "iommu", i);
+
+ sysmmu = of_find_device_by_node(np);
+ if (!sysmmu) {
+ dev_err(dev,
+ "sysmmu node '%s' is not found\n",
+ np->name);
+ break;
+ }
+
+ client->sysmmu[i] = &sysmmu->dev;
+ }
+
+ if (i < size) {
+ while (--i >= 0)
+ of_node_put(client->sysmmu[i]->of_node);
+ devm_kfree(dev, client);
+ return -ENODEV;
+ }
+
+ i = pm_genpd_add_callbacks(dev, &sysmmu_devpm_ops, NULL);
+ if (i && (i != -ENOSYS)) {
+ dev_err(dev,
+ "Failed to register 'dev_pm_ops' for iommu\n");
+ devm_kfree(dev, client);
+ return i;
+ }
+
+ dev->archdata.iommu = client;
+ break;
+ }
+ case BUS_NOTIFY_BOUND_DRIVER:
+ {
+ struct exynos_iommu_client *client = dev->archdata.iommu;
+ if (dev->archdata.iommu &&
+ (!pm_runtime_enabled(dev) ||
+ IS_ERR(dev_to_genpd(dev)))) {
+ int i;
+ for (i = 0; i < client->num_sysmmu; i++) {
+ struct sysmmu_drvdata *data;
+ pm_runtime_disable(client->sysmmu[i]);
+ data = dev_get_drvdata(client->sysmmu[i]);
+ if (!data)
+ continue;
+ data->runtime_active =
+ !pm_runtime_enabled(data->sysmmu);
+ if (data->runtime_active &&
+ is_sysmmu_active(data))
+ __sysmmu_enable_nocount(data);
+ }
+ }
+ break;
+ }
+ case BUS_NOTIFY_UNBOUND_DRIVER:
+ {
+ if (dev->archdata.iommu) {
+ __pm_genpd_remove_callbacks(dev, false);
+
+ devm_kfree(dev, dev->archdata.iommu);
+
+ dev->archdata.iommu = NULL;
+ }
+ break;
+ }
+ } /* switch (val) */
+
+ return 0;
+}
+
+static struct notifier_block sysmmu_notifier = {
+ .notifier_call = &sysmmu_hook_driver_register,
+};
+
+static int __init exynos_iommu_prepare(void)
+{
+ return bus_register_notifier(&platform_bus_type, &sysmmu_notifier);
+}
+arch_initcall(exynos_iommu_prepare);
--
1.7.2.5


2013-08-02 05:17:37

by Rahul Sharma

[permalink] [raw]
Subject: Re: [PATCH v8 10/12] iommu/exynos: add bus notifier for registering System MMU

Hi Cho,

On Fri, Jul 26, 2013 at 5:00 PM, Cho KyongHo <[email protected]> wrote:
> When a device driver is registered, all constructs to handle System MMU
> is prepared by bus notifier call.
>
> Signed-off-by: Cho KyongHo <[email protected]>
> ---
> drivers/iommu/exynos-iommu.c | 708 ++++++++++++++++++++++++++++++++---------
> 1 files changed, 552 insertions(+), 156 deletions(-)
>
> diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
> index f9853fe..c62c244 100644
> --- a/drivers/iommu/exynos-iommu.c
> +++ b/drivers/iommu/exynos-iommu.c
> @@ -27,6 +27,9 @@
> #include <linux/memblock.h>
> #include <linux/export.h>
> #include <linux/of.h>
> +#include <linux/of_platform.h>
> +#include <linux/pm_domain.h>
> +#include <linux/notifier.h>
>
> #include <asm/cacheflush.h>
> #include <asm/pgtable.h>
> @@ -80,7 +83,13 @@
> #define CTRL_BLOCK 0x7
> #define CTRL_DISABLE 0x0
>
> +#define CFG_LRU 0x1
> +#define CFG_QOS(n) ((n & 0xF) << 7)
> +#define CFG_MASK 0x0150FFFF /* Selecting bit 0-15, 20, 22 and 24 */
> +#define CFG_ACGEN (1 << 24) /* System MMU 3.3 only */
> +#define CFG_SYSSEL (1 << 22) /* System MMU 3.2 only */
> #define CFG_FLPDCACHE (1 << 20) /* System MMU 3.2+ only */
> +#define CFG_SHAREABLE (1 << 12) /* System MMU 3.x only */
>
> #define REG_MMU_CTRL 0x000
> #define REG_MMU_CFG 0x004
> @@ -154,6 +163,14 @@ static char *sysmmu_fault_name[SYSMMU_FAULTS_NUM] = {
> "UNKNOWN FAULT"
> };
>
> +struct exynos_iommu_client {
> + struct list_head node; /* entry of exynos_iommu_domain.clients */
> + struct device *dev;
> + spinlock_t lock;
> + int num_sysmmu;
> + struct device *sysmmu[0];

Shouldn't we keep limit on the max number of iommu's to a single client ? Even
this way, you will hit array overrun with multiple iommu's.

> +};
> +
> struct exynos_iommu_domain {
> struct list_head clients; /* list of sysmmu_drvdata.node */
> unsigned long *pgtable; /* lv1 page table, 16KB */
> @@ -165,12 +182,14 @@ struct exynos_iommu_domain {
> struct sysmmu_drvdata {
> struct list_head node; /* entry of exynos_iommu_domain.clients */
> struct device *sysmmu; /* System MMU's device descriptor */
> - struct device *dev; /* Owner of system MMU */
> + struct device *master; /* Owner of system MMU */
> int nsfrs;
> struct clk *clk;
> + struct clk *clk_master;
> int activations;
> rwlock_t lock;
> struct iommu_domain *domain;
> + bool runtime_active;
> unsigned long pgtable;
> void __iomem *sfrbases[0];
> };
> @@ -245,7 +264,6 @@ static void __sysmmu_tlb_invalidate_entry(void __iomem *sfrbase,
> static void __sysmmu_set_ptbase(void __iomem *sfrbase,
> unsigned long pgd)
> {
> - __raw_writel(0x1, sfrbase + REG_MMU_CFG); /* 16KB LV1, LRU */
> __raw_writel(pgd, sfrbase + REG_PT_BASE_ADDR);
>
> __sysmmu_tlb_invalidate(sfrbase);
> @@ -273,6 +291,7 @@ void exynos_sysmmu_set_prefbuf(struct device *dev,
> if (!is_sysmmu_active(data))
> goto finish;
>
> + clk_enable(data->clk_master);
> for (i = 0; i < data->nsfrs; i++) {
> if ((readl(data->sfrbases[i] + REG_MMU_VERSION) >> 28) == 3) {
> if (!sysmmu_block(data->sfrbases[i]))
> @@ -298,6 +317,7 @@ void exynos_sysmmu_set_prefbuf(struct device *dev,
> sysmmu_unblock(data->sfrbases[i]);
> }
> }
> + clk_disable(data->clk_master);
> finish:
> read_unlock_irqrestore(&data->lock, flags);
> }
> @@ -331,12 +351,13 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
> {
> /* SYSMMU is in blocked when interrupt occurred. */
> struct sysmmu_drvdata *data = dev_id;
> + struct exynos_iommu_client *client = NULL;
> enum exynos_sysmmu_inttype itype;
> unsigned long addr = -1;
> -
> int i, ret = -ENOSYS;
>
> - read_lock(&data->lock);
> + if (data->master)
> + client = data->master->archdata.iommu;
>
> WARN_ON(!is_sysmmu_active(data));
>
> @@ -348,6 +369,10 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
> break;
> }
>
> + if (client)
> + spin_lock(&client->lock);
> + read_lock(&data->lock);
> +
> if (i == data->nsfrs) {
> itype = SYSMMU_FAULT_UNKNOWN;
> } else {
> @@ -361,7 +386,7 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
> }
>
> if (data->domain)
> - ret = report_iommu_fault(data->domain, data->dev,
> + ret = report_iommu_fault(data->domain, data->master,
> addr, itype);
>
> if (!ret && (itype != SYSMMU_FAULT_UNKNOWN))
> @@ -378,177 +403,251 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
> sysmmu_unblock(data->sfrbases[i]);
>
> read_unlock(&data->lock);
> + if (client)
> + spin_unlock(&client->lock);
>
> return IRQ_HANDLED;
> }
>
> -static bool __exynos_sysmmu_disable(struct sysmmu_drvdata *data)
> +static void __sysmmu_disable_nocount(struct sysmmu_drvdata *data)
> {
> - unsigned long flags;
> - bool disabled = false;
> int i;
>
> - write_lock_irqsave(&data->lock, flags);
> + clk_enable(data->clk_master);
> + for (i = 0; i < data->nsfrs; i++) {
> + __raw_writel(CTRL_DISABLE,
> + data->sfrbases[i] + REG_MMU_CTRL);
> + __raw_writel(0, data->sfrbases[i] + REG_MMU_CFG);
> + }
>
> - if (!set_sysmmu_inactive(data))
> - goto finish;
> + clk_disable(data->clk);
> + clk_disable(data->clk_master);
> +}
>
> - for (i = 0; i < data->nsfrs; i++)
> - __raw_writel(CTRL_DISABLE, data->sfrbases[i] + REG_MMU_CTRL);
> +static bool __sysmmu_disable(struct sysmmu_drvdata *data)
> +{
> + bool disabled;
> + unsigned long flags;
>
> - if (data->clk)
> - clk_disable(data->clk);
> + write_lock_irqsave(&data->lock, flags);
>
> - disabled = true;
> - data->pgtable = 0;
> - data->domain = NULL;
> -finish:
> - write_unlock_irqrestore(&data->lock, flags);
> + disabled = set_sysmmu_inactive(data);
> +
> + if (disabled) {
> + data->pgtable = 0;
> + data->domain = NULL;
> +
> + if (data->runtime_active)
> + __sysmmu_disable_nocount(data);
>
> - if (disabled)
> dev_dbg(data->sysmmu, "Disabled\n");
> - else
> - dev_dbg(data->sysmmu, "%d times left to be disabled\n",
> + } else {
> + dev_dbg(data->sysmmu, "%d times left to disable\n",
> data->activations);
> + }
> +
> + write_unlock_irqrestore(&data->lock, flags);
>
> return disabled;
> }
>
> -/* __exynos_sysmmu_enable: Enables System MMU
> - *
> - * returns -error if an error occurred and System MMU is not enabled,
> - * 0 if the System MMU has been just enabled and 1 if System MMU was already
> - * enabled before.
> - */
> -static int __exynos_sysmmu_enable(struct sysmmu_drvdata *data,
> +
> +static void __sysmmu_init_config(struct sysmmu_drvdata *data, int idx)
> +{
> + unsigned long cfg = CFG_LRU | CFG_QOS(15);
> + int maj, min = 0;
> +
> + maj = __sysmmu_version(data, idx, &min);
> + if (maj == 3) {
> + if (min > 1) {
> + cfg |= CFG_FLPDCACHE;
> + cfg |= (min == 2) ? CFG_SYSSEL : CFG_ACGEN;
> + }
> + }
> +
> + __raw_writel(cfg, data->sfrbases[idx] + REG_MMU_CFG);
> +}
> +
> +static void __sysmmu_enable_nocount(struct sysmmu_drvdata *data)
> +{
> + int i;
> +
> + clk_enable(data->clk_master);
> + clk_enable(data->clk);
> +
> + for (i = 0; i < data->nsfrs; i++) {
> + __raw_writel(CTRL_BLOCK, data->sfrbases[i] + REG_MMU_CTRL);
> +
> + __sysmmu_init_config(data, i);
> +
> + __sysmmu_set_ptbase(data->sfrbases[i], data->pgtable);
> +
> + __raw_writel(CTRL_ENABLE, data->sfrbases[i] + REG_MMU_CTRL);
> + }
> + clk_disable(data->clk_master);
> +}
> +
> +static int __sysmmu_enable(struct sysmmu_drvdata *data,
> unsigned long pgtable, struct iommu_domain *domain)
> {
> - int i, ret = 0;
> + int ret = 0;
> unsigned long flags;
>
> write_lock_irqsave(&data->lock, flags);
> + if (set_sysmmu_active(data)) {
> + data->pgtable = pgtable;
> + data->domain = domain;
>
> - if (!set_sysmmu_active(data)) {
> - if (WARN_ON(pgtable != data->pgtable)) {
> - ret = -EBUSY;
> - set_sysmmu_inactive(data);
> - } else {
> - ret = 1;
> - }
> + if (data->runtime_active)
> + __sysmmu_enable_nocount(data);
>
> - dev_dbg(data->sysmmu, "Already enabled\n");
> - goto finish;
> + dev_dbg(data->sysmmu, "Enabled\n");
> + } else {
> + ret = (pgtable == data->pgtable) ? 1 : -EBUSY;
> +
> + dev_dbg(data->sysmmu, "already enabled\n");
> }
>
> - if (data->clk)
> - clk_enable(data->clk);
> + if (WARN_ON(ret < 0))
> + set_sysmmu_inactive(data); /* decrement count */
>
> - data->pgtable = pgtable;
> + write_unlock_irqrestore(&data->lock, flags);
>
> - for (i = 0; i < data->nsfrs; i++) {
> - unsigned int min;
> + return ret;
> +}
>
> - __sysmmu_set_ptbase(data->sfrbases[i], pgtable);
> +/* __exynos_sysmmu_enable: Enables System MMU
> + *
> + * returns -error if an error occurred and System MMU is not enabled,
> + * 0 if the System MMU has been just enabled and 1 if System MMU was already
> + * enabled before.
> + */
> +static int __exynos_sysmmu_enable(struct device *dev, unsigned long pgtable,
> + struct iommu_domain *domain)
> +{
> + int ret = 0;
> + unsigned long flags;
> + struct exynos_iommu_client *client = dev->archdata.iommu;
> + int i;
>
> - if ((__sysmmu_version(data, i, &min) == 3) && (min > 1)) {
> - unsigned long cfg;
> - cfg = __raw_readl(data->sfrbases[i] + REG_MMU_CFG);
> - __raw_writel(cfg | CFG_FLPDCACHE,
> - data->sfrbases[i] + REG_MMU_CFG);
> - }
> + if (WARN_ON(!client))
> + return -ENODEV;
>
> - __raw_writel(CTRL_ENABLE, data->sfrbases[i] + REG_MMU_CTRL);
> - }
> + spin_lock_irqsave(&client->lock, flags);
>
> - data->domain = domain;
> + for (i = 0; i < client->num_sysmmu; i++) {
> + struct sysmmu_drvdata *data =
> + dev_get_drvdata(client->sysmmu[i]);
> + ret = __sysmmu_enable(data, pgtable, domain);
> + if (ret < 0) {
> + int j;
> + for (j = 0; j < i; j++)
> + __sysmmu_disable(data);
> + break;
> + } else {
> + data->master = dev;
> + }
> + }
>
> - dev_dbg(data->sysmmu, "Enabled\n");
> -finish:
> - write_unlock_irqrestore(&data->lock, flags);
> + spin_unlock_irqrestore(&client->lock, flags);
>
> return ret;
> }
>
> int exynos_sysmmu_enable(struct device *dev, unsigned long pgtable)
> {
> - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
> int ret;
>
> BUG_ON(!memblock_is_memory(pgtable));
>
> - ret = pm_runtime_get_sync(data->sysmmu);
> - if (ret < 0) {
> - dev_dbg(data->sysmmu, "Failed to enable\n");
> - return ret;
> - }
> -
> - ret = __exynos_sysmmu_enable(data, pgtable, NULL);
> - if (WARN_ON(ret < 0)) {
> - pm_runtime_put(data->sysmmu);
> - dev_err(data->sysmmu,
> - "Already enabled with page table %#lx\n",
> - data->pgtable);
> - } else {
> - data->dev = dev;
> - }
> + ret = __exynos_sysmmu_enable(dev, pgtable, NULL);
>
> return ret;
> }
>
> static bool exynos_sysmmu_disable(struct device *dev)
> {
> - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
> - bool disabled;
> + unsigned long flags;
> + bool disabled = true;
> + struct exynos_iommu_client *client = dev->archdata.iommu;
> + int i;
>
> - disabled = __exynos_sysmmu_disable(data);
> - pm_runtime_put(data->sysmmu);
> + if (WARN_ON(!client))
> + return true;
> +
> + spin_lock_irqsave(&client->lock, flags);
> +
> + /* Every call to __sysmmu_disable() must return same result */
> + for (i = 0; i < client->num_sysmmu; i++) {
> + struct sysmmu_drvdata *data =
> + dev_get_drvdata(client->sysmmu[i]);
> + disabled = __sysmmu_disable(data);
> + if (disabled)
> + data->master = NULL;
> + }
> +
> + spin_unlock_irqrestore(&client->lock, flags);
>
> return disabled;
> }
>
> static void sysmmu_tlb_invalidate_entry(struct device *dev, unsigned long iova)
> {
> - unsigned long flags;
> - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
> + struct exynos_iommu_client *client = dev->archdata.iommu;
> + int i;
>
> - read_lock_irqsave(&data->lock, flags);
> + for (i = 0; i < client->num_sysmmu; i++) {
> + unsigned long flags;
> + struct sysmmu_drvdata *data;
>
> - if (is_sysmmu_active(data)) {
> - int i;
> - for (i = 0; i < data->nsfrs; i++) {
> - if (sysmmu_block(data->sfrbases[i])) {
> + data = dev_get_drvdata(client->sysmmu[i]);
> +
> + read_lock_irqsave(&data->lock, flags);
> + if (is_sysmmu_active(data) && data->runtime_active) {
> + int i;
> + clk_enable(data->clk_master);
> + for (i = 0; i < data->nsfrs; i++)
> __sysmmu_tlb_invalidate_entry(
> data->sfrbases[i], iova);
> - sysmmu_unblock(data->sfrbases[i]);
> - }
> + clk_disable(data->clk_master);
> + } else {
> + dev_dbg(dev,
> + "disabled. Skipping TLB invalidation @ %#lx\n",
> + iova);
> }
> - } else {
> - dev_dbg(data->sysmmu, "Disabled. Skipping invalidating TLB.\n");
> + read_unlock_irqrestore(&data->lock, flags);
> }
> -
> - read_unlock_irqrestore(&data->lock, flags);
> }
>
> void exynos_sysmmu_tlb_invalidate(struct device *dev)
> {
> - unsigned long flags;
> - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
> -
> - read_lock_irqsave(&data->lock, flags);
> + struct exynos_iommu_client *client = dev->archdata.iommu;
> + int i;
>
> - if (is_sysmmu_active(data)) {
> - int i;
> - for (i = 0; i < data->nsfrs; i++) {
> - if (sysmmu_block(data->sfrbases[i])) {
> - __sysmmu_tlb_invalidate(data->sfrbases[i]);
> - sysmmu_unblock(data->sfrbases[i]);
> + for (i = 0; i < client->num_sysmmu; i++) {
> + unsigned long flags;
> + struct sysmmu_drvdata *data;
> +
> + data = dev_get_drvdata(client->sysmmu[i]);
> +
> + read_lock_irqsave(&data->lock, flags);
> + if (is_sysmmu_active(data) &&
> + data->runtime_active) {
> + int i;
> + for (i = 0; i < data->nsfrs; i++) {
> + clk_enable(data->clk_master);
> + if (sysmmu_block(data->sfrbases[i])) {
> + __sysmmu_tlb_invalidate(
> + data->sfrbases[i]);
> + sysmmu_unblock(data->sfrbases[i]);
> + }
> + clk_disable(data->clk_master);
> }
> + } else {
> + dev_dbg(dev, "disabled. Skipping TLB invalidation\n");
> }
> - } else {
> - dev_dbg(data->sysmmu, "Disabled. Skipping invalidating TLB.\n");
> + read_unlock_irqrestore(&data->lock, flags);
> }
> -
> - read_unlock_irqrestore(&data->lock, flags);
> }
>
> static int __init exynos_sysmmu_probe(struct platform_device *pdev)
> @@ -610,12 +709,32 @@ static int __init exynos_sysmmu_probe(struct platform_device *pdev)
> pm_runtime_enable(dev);
>
> data->sysmmu = dev;
> +
> data->clk = devm_clk_get(dev, "sysmmu");
> if (IS_ERR(data->clk)) {
> dev_info(dev, "No gate clock found!\n");
> data->clk = NULL;
> }
>
> + ret = clk_prepare(data->clk);
> + if (ret) {
> + dev_err(dev, "Failed to prepare clk\n");
> + return ret;
> + }
> +
> + data->clk_master = devm_clk_get(dev, "master");
> + if (IS_ERR(data->clk_master))
> + data->clk_master = NULL;
> +
> + ret = clk_prepare(data->clk_master);
> + if (ret) {
> + clk_unprepare(data->clk);
> + dev_err(dev, "Failed to prepare master's clk\n");
> + return ret;
> + }
> +
> + data->runtime_active = !pm_runtime_enabled(dev);
> +
> rwlock_init(&data->lock);
> INIT_LIST_HEAD(&data->node);
>
> @@ -625,6 +744,34 @@ static int __init exynos_sysmmu_probe(struct platform_device *pdev)
> return ret;
> }
>
> +#ifdef CONFIG_PM_SLEEP
> +static int sysmmu_suspend(struct device *dev)
> +{
> + struct sysmmu_drvdata *data = dev_get_drvdata(dev);
> + unsigned long flags;
> + read_lock_irqsave(&data->lock, flags);
> + if (is_sysmmu_active(data) &&
> + (!pm_runtime_enabled(dev) || data->runtime_active))
> + __sysmmu_disable_nocount(data);
> + read_unlock_irqrestore(&data->lock, flags);
> + return 0;
> +}
> +
> +static int sysmmu_resume(struct device *dev)
> +{
> + struct sysmmu_drvdata *data = dev_get_drvdata(dev);
> + unsigned long flags;
> + read_lock_irqsave(&data->lock, flags);
> + if (is_sysmmu_active(data) &&
> + (!pm_runtime_enabled(dev) || data->runtime_active))
> + __sysmmu_enable_nocount(data);
> + read_unlock_irqrestore(&data->lock, flags);
> + return 0;
> +}
> +#endif
> +
> +static SIMPLE_DEV_PM_OPS(sysmmu_pm_ops, sysmmu_suspend, sysmmu_resume);
> +
> #ifdef CONFIG_OF
> static struct of_device_id sysmmu_of_match[] __initconst = {
> { .compatible = "samsung,exynos4210-sysmmu", },
> @@ -637,6 +784,7 @@ static struct platform_driver exynos_sysmmu_driver __refdata = {
> .driver = {
> .owner = THIS_MODULE,
> .name = "exynos-sysmmu",
> + .pm = &sysmmu_pm_ops,
> .of_match_table = of_match_ptr(sysmmu_of_match),
> }
> };
> @@ -689,7 +837,7 @@ err_pgtable:
> static void exynos_iommu_domain_destroy(struct iommu_domain *domain)
> {
> struct exynos_iommu_domain *priv = domain->priv;
> - struct sysmmu_drvdata *data;
> + struct exynos_iommu_client *client;
> unsigned long flags;
> int i;
>
> @@ -697,11 +845,14 @@ static void exynos_iommu_domain_destroy(struct iommu_domain *domain)
>
> spin_lock_irqsave(&priv->lock, flags);
>
> - list_for_each_entry(data, &priv->clients, node) {
> - while (!exynos_sysmmu_disable(data->dev))
> + list_for_each_entry(client, &priv->clients, node) {
> + while (!exynos_sysmmu_disable(client->dev))
> ; /* until System MMU is actually disabled */
> }
>
> + while (!list_empty(&priv->clients))
> + list_del_init(priv->clients.next);
> +
> spin_unlock_irqrestore(&priv->lock, flags);
>
> for (i = 0; i < NUM_LV1ENTRIES; i++)
> @@ -718,41 +869,26 @@ static void exynos_iommu_domain_destroy(struct iommu_domain *domain)
> static int exynos_iommu_attach_device(struct iommu_domain *domain,
> struct device *dev)
> {
> - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
> + struct exynos_iommu_client *client = dev->archdata.iommu;
> struct exynos_iommu_domain *priv = domain->priv;
> unsigned long flags;
> int ret;
>
> - ret = pm_runtime_get_sync(data->sysmmu);
> - if (ret < 0)
> - return ret;
> -
> - ret = 0;
> -
> spin_lock_irqsave(&priv->lock, flags);
>
> - ret = __exynos_sysmmu_enable(data, __pa(priv->pgtable), domain);
> -
> - if (ret == 0) {
> - /* 'data->node' must not be appeared in priv->clients */
> - BUG_ON(!list_empty(&data->node));
> - data->dev = dev;
> - list_add_tail(&data->node, &priv->clients);
> - }
> + ret = __exynos_sysmmu_enable(dev, __pa(priv->pgtable), domain);
> + if (ret == 0)
> + list_add_tail(&client->node, &priv->clients);
>
> spin_unlock_irqrestore(&priv->lock, flags);
>
> - if (ret < 0) {
> + if (ret < 0)
> dev_err(dev, "%s: Failed to attach IOMMU with pgtable %#lx\n",
> __func__, __pa(priv->pgtable));
> - pm_runtime_put(data->sysmmu);
> - } else if (ret > 0) {
> - dev_dbg(dev, "%s: IOMMU with pgtable 0x%lx already attached\n",
> - __func__, __pa(priv->pgtable));
> - } else {
> - dev_dbg(dev, "%s: Attached new IOMMU with pgtable 0x%lx\n",
> - __func__, __pa(priv->pgtable));
> - }
> + else
> + dev_dbg(dev, "%s: Attached IOMMU with pgtable 0x%lx%s\n",
> + __func__, __pa(priv->pgtable),
> + (ret == 0) ? "" : ", again");
>
> return ret;
> }
> @@ -760,39 +896,27 @@ static int exynos_iommu_attach_device(struct iommu_domain *domain,
> static void exynos_iommu_detach_device(struct iommu_domain *domain,
> struct device *dev)
> {
> - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
> + struct exynos_iommu_client *client = NULL;
> struct exynos_iommu_domain *priv = domain->priv;
> - struct list_head *pos;
> unsigned long flags;
> - bool found = false;
>
> spin_lock_irqsave(&priv->lock, flags);
>
> - list_for_each(pos, &priv->clients) {
> - if (list_entry(pos, struct sysmmu_drvdata, node) == data) {
> - found = true;
> + list_for_each_entry(client, &priv->clients, node) {
> + if (client == dev->archdata.iommu) {
> + if (exynos_sysmmu_disable(dev))
> + list_del_init(&client->node);
> break;
> }
> }
>
> - if (!found)
> - goto finish;
> + spin_unlock_irqrestore(&priv->lock, flags);
>
> - if (__exynos_sysmmu_disable(data)) {
> + if (client == dev->archdata.iommu)
> dev_dbg(dev, "%s: Detached IOMMU with pgtable %#lx\n",
> __func__, __pa(priv->pgtable));
> - list_del_init(&data->node);
> -
> - } else {
> - dev_dbg(dev, "%s: Detaching IOMMU with pgtable %#lx delayed",
> - __func__, __pa(priv->pgtable));
> - }
> -
> -finish:
> - spin_unlock_irqrestore(&priv->lock, flags);
> -
> - if (found)
> - pm_runtime_put(data->sysmmu);
> + else
> + dev_dbg(dev, "%s: No IOMMU is attached\n", __func__);
> }
>
> static unsigned long *alloc_lv2entry(unsigned long *sent, unsigned long iova,
> @@ -914,7 +1038,7 @@ static size_t exynos_iommu_unmap(struct iommu_domain *domain,
> unsigned long iova, size_t size)
> {
> struct exynos_iommu_domain *priv = domain->priv;
> - struct sysmmu_drvdata *data;
> + struct exynos_iommu_client *client;
> unsigned long flags;
> unsigned long *ent;
> size_t err_pgsize;
> @@ -975,8 +1099,8 @@ done:
> spin_unlock_irqrestore(&priv->pgtablelock, flags);
>
> spin_lock_irqsave(&priv->lock, flags);
> - list_for_each_entry(data, &priv->clients, node)
> - sysmmu_tlb_invalidate_entry(data->dev, iova);
> + list_for_each_entry(client, &priv->clients, node)
> + sysmmu_tlb_invalidate_entry(client->dev, iova);
> spin_unlock_irqrestore(&priv->lock, flags);
>
> return size;
> @@ -1055,3 +1179,275 @@ static int __init exynos_iommu_init(void)
> return ret;
> }
> subsys_initcall(exynos_iommu_init);
> +
> +#ifdef CONFIG_PM_SLEEP
> +static int sysmmu_pm_genpd_suspend(struct device *dev)
> +{
> + struct exynos_iommu_client *client = dev->archdata.iommu;
> + int ret = 0;
> + int i;
> +
> + for (i = 0; i < client->num_sysmmu; i++) {
> + ret = pm_generic_suspend(client->sysmmu[i]);
> + if (ret)
> + break;
> + }
> +
> + if (!ret)
> + ret = pm_generic_suspend(dev);
> +
> + if (ret) {
> + int j;
> +
> + for (j = 0; j < i; j++)
> + pm_generic_resume(client->sysmmu[j]);
> + }
> +
> + return ret;
> +}
> +
> +static int sysmmu_pm_genpd_resume(struct device *dev)
> +{
> + struct exynos_iommu_client *client = dev->archdata.iommu;
> + int ret = 0;
> + int i;
> +
> + for (i = 0; i < client->num_sysmmu; i++) {
> + ret = pm_generic_resume(client->sysmmu[i]);
> + if (ret)
> + break;
> + }
> +
> + if (!ret)
> + ret = pm_generic_resume(dev);
> +
> + if (ret) {
> + int j;
> +
> + for (j = 0; j < i; j++)
> + pm_generic_suspend(client->sysmmu[j]);
> + }
> +
> + return ret;
> +}
> +#endif
> +
> +#ifdef CONFIG_PM_RUNTIME
> +static void sysmmu_restore_state(struct device *sysmmu)
> +{
> + struct sysmmu_drvdata *data = dev_get_drvdata(sysmmu);
> + unsigned long flags;
> +
> + spin_lock_irqsave(&data->lock, flags);
> + data->runtime_active = true;
> + if (is_sysmmu_active(data))
> + __sysmmu_enable_nocount(data);
> + spin_unlock_irqrestore(&data->lock, flags);
> +}
> +
> +static void sysmmu_save_state(struct device *sysmmu)
> +{
> + struct sysmmu_drvdata *data = dev_get_drvdata(sysmmu);
> + unsigned long flags;
> +
> + spin_lock_irqsave(&data->lock, flags);
> + if (is_sysmmu_active(data))
> + __sysmmu_disable_nocount(data);
> + data->runtime_active = false;
> + spin_unlock_irqrestore(&data->lock, flags);
> +}
> +
> +static int sysmmu_pm_genpd_save_state(struct device *dev)
> +{
> + struct exynos_iommu_client *client = dev->archdata.iommu;
> + int (*cb)(struct device *__dev);
> + int i;
> +
> + if (dev->type && dev->type->pm)
> + cb = dev->type->pm->runtime_suspend;
> + else if (dev->class && dev->class->pm)
> + cb = dev->class->pm->runtime_suspend;
> + else if (dev->bus && dev->bus->pm)
> + cb = dev->bus->pm->runtime_suspend;
> + else
> + cb = NULL;
> +
> + if (!cb && dev->driver && dev->driver->pm)
> + cb = dev->driver->pm->runtime_suspend;
> +
> + if (cb) {
> + int ret;
> +
> + ret = cb(dev);
> + if (ret)
> + return ret;
> + }
> +
> + for (i = 0; i < client->num_sysmmu; i++)
> + sysmmu_save_state(client->sysmmu[i]);
> +
> + return 0;
> +}
> +
> +static int sysmmu_pm_genpd_restore_state(struct device *dev)
> +{
> + struct exynos_iommu_client *client = dev->archdata.iommu;
> + int (*cb)(struct device *__dev);
> + int i;
> +
> + if (dev->type && dev->type->pm)
> + cb = dev->type->pm->runtime_resume;
> + else if (dev->class && dev->class->pm)
> + cb = dev->class->pm->runtime_resume;
> + else if (dev->bus && dev->bus->pm)
> + cb = dev->bus->pm->runtime_resume;
> + else
> + cb = NULL;
> +
> + if (!cb && dev->driver && dev->driver->pm)
> + cb = dev->driver->pm->runtime_resume;
> +
> + for (i = 0; i < client->num_sysmmu; i++)
> + sysmmu_restore_state(client->sysmmu[i]);
> +
> + if (cb) {
> + int ret;
> + ret = cb(dev);
> + if (ret) {
> + for (i = 0; i < client->num_sysmmu; i++)
> + sysmmu_save_state(client->sysmmu[i]);
> + return ret;
> + }
> + }
> +
> + return 0;
> +}
> +#endif
> +
> +#ifdef CONFIG_PM_GENERIC_DOMAINS
> +struct gpd_dev_ops sysmmu_devpm_ops = {
> +#ifdef CONFIG_PM_RUNTIME
> + .save_state = &sysmmu_pm_genpd_save_state,
> + .restore_state = &sysmmu_pm_genpd_restore_state,
> +#endif
> +#ifdef CONFIG_PM_SLEEP
> + .suspend = &sysmmu_pm_genpd_suspend,
> + .resume = &sysmmu_pm_genpd_resume,
> +#endif
> +};
> +#endif /* CONFIG_PM_GENERIC_DOMAINS */
> +
> +static int sysmmu_hook_driver_register(struct notifier_block *nb,
> + unsigned long val,
> + void *p)
> +{
> + struct device *dev = p;
> +
> + switch (val) {
> + case BUS_NOTIFY_BIND_DRIVER:
> + {
> + int i = 0;
> + int size = 0;

You can drop the initialization here. They are getting initialised
before actual use.

> + const __be32 *phandle;
> + struct exynos_iommu_client *client;
> +
> + phandle = of_get_property(dev->of_node, "iommu", &size);
> + if (!phandle)
> + break;
> +
> + size = size / sizeof(*phandle); /* number of elements */
> +
> + client = devm_kzalloc(dev, sizeof(*client) * size, GFP_KERNEL);

You do not need to allocate memory of size "sizeof(*client) * size" ? It should
always be sizeof(*client).

> + if (!client) {
> + dev_err(dev, "No Memory for exynos_iommu_client\n");
> + return -ENOMEM;
> + }
> +
> + client->num_sysmmu = size;
> + client->dev = dev;
> + INIT_LIST_HEAD(&client->node);
> + spin_lock_init(&client->lock);
> +
> + for (i = 0; i < size; i++) {
> + struct device_node *np;
> + struct platform_device *sysmmu;
> +
> + /* this always success: see above of_find_property() */
> + np = of_parse_phandle(dev->of_node, "iommu", i);
> +
> + sysmmu = of_find_device_by_node(np);
> + if (!sysmmu) {
> + dev_err(dev,
> + "sysmmu node '%s' is not found\n",
> + np->name);
> + break;
> + }
> +
> + client->sysmmu[i] = &sysmmu->dev;

Your array has space for single 'device *'. You should allocate memory to
client->sysmmu before accessing indexes above 0.

As if now, It is not corrupting other's memory since you have allocated a
much bigger chunk for your client pointer which is wrong IMO.

regards,
Rahul Sharma

> + }
> +
> + if (i < size) {
> + while (--i >= 0)
> + of_node_put(client->sysmmu[i]->of_node);
> + devm_kfree(dev, client);
> + return -ENODEV;
> + }
> +
> + i = pm_genpd_add_callbacks(dev, &sysmmu_devpm_ops, NULL);
> + if (i && (i != -ENOSYS)) {
> + dev_err(dev,
> + "Failed to register 'dev_pm_ops' for iommu\n");
> + devm_kfree(dev, client);
> + return i;
> + }
> +
> + dev->archdata.iommu = client;
> + break;
> + }
> + case BUS_NOTIFY_BOUND_DRIVER:
> + {
> + struct exynos_iommu_client *client = dev->archdata.iommu;
> + if (dev->archdata.iommu &&
> + (!pm_runtime_enabled(dev) ||
> + IS_ERR(dev_to_genpd(dev)))) {
> + int i;
> + for (i = 0; i < client->num_sysmmu; i++) {
> + struct sysmmu_drvdata *data;
> + pm_runtime_disable(client->sysmmu[i]);
> + data = dev_get_drvdata(client->sysmmu[i]);
> + if (!data)
> + continue;
> + data->runtime_active =
> + !pm_runtime_enabled(data->sysmmu);
> + if (data->runtime_active &&
> + is_sysmmu_active(data))
> + __sysmmu_enable_nocount(data);
> + }
> + }
> + break;
> + }
> + case BUS_NOTIFY_UNBOUND_DRIVER:
> + {
> + if (dev->archdata.iommu) {
> + __pm_genpd_remove_callbacks(dev, false);
> +
> + devm_kfree(dev, dev->archdata.iommu);
> +
> + dev->archdata.iommu = NULL;
> + }
> + break;
> + }
> + } /* switch (val) */
> +
> + return 0;
> +}
> +
> +static struct notifier_block sysmmu_notifier = {
> + .notifier_call = &sysmmu_hook_driver_register,
> +};
> +
> +static int __init exynos_iommu_prepare(void)
> +{
> + return bus_register_notifier(&platform_bus_type, &sysmmu_notifier);
> +}
> +arch_initcall(exynos_iommu_prepare);
> --
> 1.7.2.5
>
>
> _______________________________________________
> iommu mailing list
> [email protected]
> https://lists.linuxfoundation.org/mailman/listinfo/iommu

2013-08-02 06:42:41

by Cho KyongHo

[permalink] [raw]
Subject: RE: [PATCH v8 10/12] iommu/exynos: add bus notifier for registering System MMU

> -----Original Message-----
> From: Rahul Sharma [mailto:[email protected]]
> Sent: Friday, August 02, 2013 2:18 PM
>
> Hi Cho,
>
> On Fri, Jul 26, 2013 at 5:00 PM, Cho KyongHo <[email protected]> wrote:
> > When a device driver is registered, all constructs to handle System MMU
> > is prepared by bus notifier call.
> >
> > Signed-off-by: Cho KyongHo <[email protected]>
> > ---
> > drivers/iommu/exynos-iommu.c | 708 ++++++++++++++++++++++++++++++++---------
> > 1 files changed, 552 insertions(+), 156 deletions(-)
> >
> > diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
> > index f9853fe..c62c244 100644
> > --- a/drivers/iommu/exynos-iommu.c
> > +++ b/drivers/iommu/exynos-iommu.c
> > @@ -27,6 +27,9 @@
> > #include <linux/memblock.h>
> > #include <linux/export.h>
> > #include <linux/of.h>
> > +#include <linux/of_platform.h>
> > +#include <linux/pm_domain.h>
> > +#include <linux/notifier.h>
> >
> > #include <asm/cacheflush.h>
> > #include <asm/pgtable.h>
> > @@ -80,7 +83,13 @@
> > #define CTRL_BLOCK 0x7
> > #define CTRL_DISABLE 0x0
> >
> > +#define CFG_LRU 0x1
> > +#define CFG_QOS(n) ((n & 0xF) << 7)
> > +#define CFG_MASK 0x0150FFFF /* Selecting bit 0-15, 20, 22 and 24 */
> > +#define CFG_ACGEN (1 << 24) /* System MMU 3.3 only */
> > +#define CFG_SYSSEL (1 << 22) /* System MMU 3.2 only */
> > #define CFG_FLPDCACHE (1 << 20) /* System MMU 3.2+ only */
> > +#define CFG_SHAREABLE (1 << 12) /* System MMU 3.x only */
> >
> > #define REG_MMU_CTRL 0x000
> > #define REG_MMU_CFG 0x004
> > @@ -154,6 +163,14 @@ static char *sysmmu_fault_name[SYSMMU_FAULTS_NUM] = {
> > "UNKNOWN FAULT"
> > };
> >
> > +struct exynos_iommu_client {
> > + struct list_head node; /* entry of exynos_iommu_domain.clients */
> > + struct device *dev;
> > + spinlock_t lock;
> > + int num_sysmmu;
> > + struct device *sysmmu[0];
>
> Shouldn't we keep limit on the max number of iommu's to a single client ? Even
> this way, you will hit array overrun with multiple iommu's.
>

I don't think it is needed to fix the size of the array because
we know the size of the array in booting time.
sysmmu[0] is just a placeholder of array.

> > +};
> > +
> > struct exynos_iommu_domain {
> > struct list_head clients; /* list of sysmmu_drvdata.node */
> > unsigned long *pgtable; /* lv1 page table, 16KB */
> > @@ -165,12 +182,14 @@ struct exynos_iommu_domain {
> > struct sysmmu_drvdata {
> > struct list_head node; /* entry of exynos_iommu_domain.clients */
> > struct device *sysmmu; /* System MMU's device descriptor */
> > - struct device *dev; /* Owner of system MMU */
> > + struct device *master; /* Owner of system MMU */
> > int nsfrs;
> > struct clk *clk;
> > + struct clk *clk_master;
> > int activations;
> > rwlock_t lock;
> > struct iommu_domain *domain;
> > + bool runtime_active;
> > unsigned long pgtable;
> > void __iomem *sfrbases[0];
> > };
> > @@ -245,7 +264,6 @@ static void __sysmmu_tlb_invalidate_entry(void __iomem *sfrbase,
> > static void __sysmmu_set_ptbase(void __iomem *sfrbase,
> > unsigned long pgd)
> > {
> > - __raw_writel(0x1, sfrbase + REG_MMU_CFG); /* 16KB LV1, LRU */
> > __raw_writel(pgd, sfrbase + REG_PT_BASE_ADDR);
> >
> > __sysmmu_tlb_invalidate(sfrbase);
> > @@ -273,6 +291,7 @@ void exynos_sysmmu_set_prefbuf(struct device *dev,
> > if (!is_sysmmu_active(data))
> > goto finish;
> >
> > + clk_enable(data->clk_master);
> > for (i = 0; i < data->nsfrs; i++) {
> > if ((readl(data->sfrbases[i] + REG_MMU_VERSION) >> 28) == 3) {
> > if (!sysmmu_block(data->sfrbases[i]))
> > @@ -298,6 +317,7 @@ void exynos_sysmmu_set_prefbuf(struct device *dev,
> > sysmmu_unblock(data->sfrbases[i]);
> > }
> > }
> > + clk_disable(data->clk_master);
> > finish:
> > read_unlock_irqrestore(&data->lock, flags);
> > }
> > @@ -331,12 +351,13 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
> > {
> > /* SYSMMU is in blocked when interrupt occurred. */
> > struct sysmmu_drvdata *data = dev_id;
> > + struct exynos_iommu_client *client = NULL;
> > enum exynos_sysmmu_inttype itype;
> > unsigned long addr = -1;
> > -
> > int i, ret = -ENOSYS;
> >
> > - read_lock(&data->lock);
> > + if (data->master)
> > + client = data->master->archdata.iommu;
> >
> > WARN_ON(!is_sysmmu_active(data));
> >
> > @@ -348,6 +369,10 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
> > break;
> > }
> >
> > + if (client)
> > + spin_lock(&client->lock);
> > + read_lock(&data->lock);
> > +
> > if (i == data->nsfrs) {
> > itype = SYSMMU_FAULT_UNKNOWN;
> > } else {
> > @@ -361,7 +386,7 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
> > }
> >
> > if (data->domain)
> > - ret = report_iommu_fault(data->domain, data->dev,
> > + ret = report_iommu_fault(data->domain, data->master,
> > addr, itype);
> >
> > if (!ret && (itype != SYSMMU_FAULT_UNKNOWN))
> > @@ -378,177 +403,251 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
> > sysmmu_unblock(data->sfrbases[i]);
> >
> > read_unlock(&data->lock);
> > + if (client)
> > + spin_unlock(&client->lock);
> >
> > return IRQ_HANDLED;
> > }
> >
> > -static bool __exynos_sysmmu_disable(struct sysmmu_drvdata *data)
> > +static void __sysmmu_disable_nocount(struct sysmmu_drvdata *data)
> > {
> > - unsigned long flags;
> > - bool disabled = false;
> > int i;
> >
> > - write_lock_irqsave(&data->lock, flags);
> > + clk_enable(data->clk_master);
> > + for (i = 0; i < data->nsfrs; i++) {
> > + __raw_writel(CTRL_DISABLE,
> > + data->sfrbases[i] + REG_MMU_CTRL);
> > + __raw_writel(0, data->sfrbases[i] + REG_MMU_CFG);
> > + }
> >
> > - if (!set_sysmmu_inactive(data))
> > - goto finish;
> > + clk_disable(data->clk);
> > + clk_disable(data->clk_master);
> > +}
> >
> > - for (i = 0; i < data->nsfrs; i++)
> > - __raw_writel(CTRL_DISABLE, data->sfrbases[i] + REG_MMU_CTRL);
> > +static bool __sysmmu_disable(struct sysmmu_drvdata *data)
> > +{
> > + bool disabled;
> > + unsigned long flags;
> >
> > - if (data->clk)
> > - clk_disable(data->clk);
> > + write_lock_irqsave(&data->lock, flags);
> >
> > - disabled = true;
> > - data->pgtable = 0;
> > - data->domain = NULL;
> > -finish:
> > - write_unlock_irqrestore(&data->lock, flags);
> > + disabled = set_sysmmu_inactive(data);
> > +
> > + if (disabled) {
> > + data->pgtable = 0;
> > + data->domain = NULL;
> > +
> > + if (data->runtime_active)
> > + __sysmmu_disable_nocount(data);
> >
> > - if (disabled)
> > dev_dbg(data->sysmmu, "Disabled\n");
> > - else
> > - dev_dbg(data->sysmmu, "%d times left to be disabled\n",
> > + } else {
> > + dev_dbg(data->sysmmu, "%d times left to disable\n",
> > data->activations);
> > + }
> > +
> > + write_unlock_irqrestore(&data->lock, flags);
> >
> > return disabled;
> > }
> >
> > -/* __exynos_sysmmu_enable: Enables System MMU
> > - *
> > - * returns -error if an error occurred and System MMU is not enabled,
> > - * 0 if the System MMU has been just enabled and 1 if System MMU was already
> > - * enabled before.
> > - */
> > -static int __exynos_sysmmu_enable(struct sysmmu_drvdata *data,
> > +
> > +static void __sysmmu_init_config(struct sysmmu_drvdata *data, int idx)
> > +{
> > + unsigned long cfg = CFG_LRU | CFG_QOS(15);
> > + int maj, min = 0;
> > +
> > + maj = __sysmmu_version(data, idx, &min);
> > + if (maj == 3) {
> > + if (min > 1) {
> > + cfg |= CFG_FLPDCACHE;
> > + cfg |= (min == 2) ? CFG_SYSSEL : CFG_ACGEN;
> > + }
> > + }
> > +
> > + __raw_writel(cfg, data->sfrbases[idx] + REG_MMU_CFG);
> > +}
> > +
> > +static void __sysmmu_enable_nocount(struct sysmmu_drvdata *data)
> > +{
> > + int i;
> > +
> > + clk_enable(data->clk_master);
> > + clk_enable(data->clk);
> > +
> > + for (i = 0; i < data->nsfrs; i++) {
> > + __raw_writel(CTRL_BLOCK, data->sfrbases[i] + REG_MMU_CTRL);
> > +
> > + __sysmmu_init_config(data, i);
> > +
> > + __sysmmu_set_ptbase(data->sfrbases[i], data->pgtable);
> > +
> > + __raw_writel(CTRL_ENABLE, data->sfrbases[i] + REG_MMU_CTRL);
> > + }
> > + clk_disable(data->clk_master);
> > +}
> > +
> > +static int __sysmmu_enable(struct sysmmu_drvdata *data,
> > unsigned long pgtable, struct iommu_domain *domain)
> > {
> > - int i, ret = 0;
> > + int ret = 0;
> > unsigned long flags;
> >
> > write_lock_irqsave(&data->lock, flags);
> > + if (set_sysmmu_active(data)) {
> > + data->pgtable = pgtable;
> > + data->domain = domain;
> >
> > - if (!set_sysmmu_active(data)) {
> > - if (WARN_ON(pgtable != data->pgtable)) {
> > - ret = -EBUSY;
> > - set_sysmmu_inactive(data);
> > - } else {
> > - ret = 1;
> > - }
> > + if (data->runtime_active)
> > + __sysmmu_enable_nocount(data);
> >
> > - dev_dbg(data->sysmmu, "Already enabled\n");
> > - goto finish;
> > + dev_dbg(data->sysmmu, "Enabled\n");
> > + } else {
> > + ret = (pgtable == data->pgtable) ? 1 : -EBUSY;
> > +
> > + dev_dbg(data->sysmmu, "already enabled\n");
> > }
> >
> > - if (data->clk)
> > - clk_enable(data->clk);
> > + if (WARN_ON(ret < 0))
> > + set_sysmmu_inactive(data); /* decrement count */
> >
> > - data->pgtable = pgtable;
> > + write_unlock_irqrestore(&data->lock, flags);
> >
> > - for (i = 0; i < data->nsfrs; i++) {
> > - unsigned int min;
> > + return ret;
> > +}
> >
> > - __sysmmu_set_ptbase(data->sfrbases[i], pgtable);
> > +/* __exynos_sysmmu_enable: Enables System MMU
> > + *
> > + * returns -error if an error occurred and System MMU is not enabled,
> > + * 0 if the System MMU has been just enabled and 1 if System MMU was already
> > + * enabled before.
> > + */
> > +static int __exynos_sysmmu_enable(struct device *dev, unsigned long pgtable,
> > + struct iommu_domain *domain)
> > +{
> > + int ret = 0;
> > + unsigned long flags;
> > + struct exynos_iommu_client *client = dev->archdata.iommu;
> > + int i;
> >
> > - if ((__sysmmu_version(data, i, &min) == 3) && (min > 1)) {
> > - unsigned long cfg;
> > - cfg = __raw_readl(data->sfrbases[i] + REG_MMU_CFG);
> > - __raw_writel(cfg | CFG_FLPDCACHE,
> > - data->sfrbases[i] + REG_MMU_CFG);
> > - }
> > + if (WARN_ON(!client))
> > + return -ENODEV;
> >
> > - __raw_writel(CTRL_ENABLE, data->sfrbases[i] + REG_MMU_CTRL);
> > - }
> > + spin_lock_irqsave(&client->lock, flags);
> >
> > - data->domain = domain;
> > + for (i = 0; i < client->num_sysmmu; i++) {
> > + struct sysmmu_drvdata *data =
> > + dev_get_drvdata(client->sysmmu[i]);
> > + ret = __sysmmu_enable(data, pgtable, domain);
> > + if (ret < 0) {
> > + int j;
> > + for (j = 0; j < i; j++)
> > + __sysmmu_disable(data);
> > + break;
> > + } else {
> > + data->master = dev;
> > + }
> > + }
> >
> > - dev_dbg(data->sysmmu, "Enabled\n");
> > -finish:
> > - write_unlock_irqrestore(&data->lock, flags);
> > + spin_unlock_irqrestore(&client->lock, flags);
> >
> > return ret;
> > }
> >
> > int exynos_sysmmu_enable(struct device *dev, unsigned long pgtable)
> > {
> > - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
> > int ret;
> >
> > BUG_ON(!memblock_is_memory(pgtable));
> >
> > - ret = pm_runtime_get_sync(data->sysmmu);
> > - if (ret < 0) {
> > - dev_dbg(data->sysmmu, "Failed to enable\n");
> > - return ret;
> > - }
> > -
> > - ret = __exynos_sysmmu_enable(data, pgtable, NULL);
> > - if (WARN_ON(ret < 0)) {
> > - pm_runtime_put(data->sysmmu);
> > - dev_err(data->sysmmu,
> > - "Already enabled with page table %#lx\n",
> > - data->pgtable);
> > - } else {
> > - data->dev = dev;
> > - }
> > + ret = __exynos_sysmmu_enable(dev, pgtable, NULL);
> >
> > return ret;
> > }
> >
> > static bool exynos_sysmmu_disable(struct device *dev)
> > {
> > - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
> > - bool disabled;
> > + unsigned long flags;
> > + bool disabled = true;
> > + struct exynos_iommu_client *client = dev->archdata.iommu;
> > + int i;
> >
> > - disabled = __exynos_sysmmu_disable(data);
> > - pm_runtime_put(data->sysmmu);
> > + if (WARN_ON(!client))
> > + return true;
> > +
> > + spin_lock_irqsave(&client->lock, flags);
> > +
> > + /* Every call to __sysmmu_disable() must return same result */
> > + for (i = 0; i < client->num_sysmmu; i++) {
> > + struct sysmmu_drvdata *data =
> > + dev_get_drvdata(client->sysmmu[i]);
> > + disabled = __sysmmu_disable(data);
> > + if (disabled)
> > + data->master = NULL;
> > + }
> > +
> > + spin_unlock_irqrestore(&client->lock, flags);
> >
> > return disabled;
> > }
> >
> > static void sysmmu_tlb_invalidate_entry(struct device *dev, unsigned long iova)
> > {
> > - unsigned long flags;
> > - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
> > + struct exynos_iommu_client *client = dev->archdata.iommu;
> > + int i;
> >
> > - read_lock_irqsave(&data->lock, flags);
> > + for (i = 0; i < client->num_sysmmu; i++) {
> > + unsigned long flags;
> > + struct sysmmu_drvdata *data;
> >
> > - if (is_sysmmu_active(data)) {
> > - int i;
> > - for (i = 0; i < data->nsfrs; i++) {
> > - if (sysmmu_block(data->sfrbases[i])) {
> > + data = dev_get_drvdata(client->sysmmu[i]);
> > +
> > + read_lock_irqsave(&data->lock, flags);
> > + if (is_sysmmu_active(data) && data->runtime_active) {
> > + int i;
> > + clk_enable(data->clk_master);
> > + for (i = 0; i < data->nsfrs; i++)
> > __sysmmu_tlb_invalidate_entry(
> > data->sfrbases[i], iova);
> > - sysmmu_unblock(data->sfrbases[i]);
> > - }
> > + clk_disable(data->clk_master);
> > + } else {
> > + dev_dbg(dev,
> > + "disabled. Skipping TLB invalidation @ %#lx\n",
> > + iova);
> > }
> > - } else {
> > - dev_dbg(data->sysmmu, "Disabled. Skipping invalidating TLB.\n");
> > + read_unlock_irqrestore(&data->lock, flags);
> > }
> > -
> > - read_unlock_irqrestore(&data->lock, flags);
> > }
> >
> > void exynos_sysmmu_tlb_invalidate(struct device *dev)
> > {
> > - unsigned long flags;
> > - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
> > -
> > - read_lock_irqsave(&data->lock, flags);
> > + struct exynos_iommu_client *client = dev->archdata.iommu;
> > + int i;
> >
> > - if (is_sysmmu_active(data)) {
> > - int i;
> > - for (i = 0; i < data->nsfrs; i++) {
> > - if (sysmmu_block(data->sfrbases[i])) {
> > - __sysmmu_tlb_invalidate(data->sfrbases[i]);
> > - sysmmu_unblock(data->sfrbases[i]);
> > + for (i = 0; i < client->num_sysmmu; i++) {
> > + unsigned long flags;
> > + struct sysmmu_drvdata *data;
> > +
> > + data = dev_get_drvdata(client->sysmmu[i]);
> > +
> > + read_lock_irqsave(&data->lock, flags);
> > + if (is_sysmmu_active(data) &&
> > + data->runtime_active) {
> > + int i;
> > + for (i = 0; i < data->nsfrs; i++) {
> > + clk_enable(data->clk_master);
> > + if (sysmmu_block(data->sfrbases[i])) {
> > + __sysmmu_tlb_invalidate(
> > + data->sfrbases[i]);
> > + sysmmu_unblock(data->sfrbases[i]);
> > + }
> > + clk_disable(data->clk_master);
> > }
> > + } else {
> > + dev_dbg(dev, "disabled. Skipping TLB invalidation\n");
> > }
> > - } else {
> > - dev_dbg(data->sysmmu, "Disabled. Skipping invalidating TLB.\n");
> > + read_unlock_irqrestore(&data->lock, flags);
> > }
> > -
> > - read_unlock_irqrestore(&data->lock, flags);
> > }
> >
> > static int __init exynos_sysmmu_probe(struct platform_device *pdev)
> > @@ -610,12 +709,32 @@ static int __init exynos_sysmmu_probe(struct platform_device *pdev)
> > pm_runtime_enable(dev);
> >
> > data->sysmmu = dev;
> > +
> > data->clk = devm_clk_get(dev, "sysmmu");
> > if (IS_ERR(data->clk)) {
> > dev_info(dev, "No gate clock found!\n");
> > data->clk = NULL;
> > }
> >
> > + ret = clk_prepare(data->clk);
> > + if (ret) {
> > + dev_err(dev, "Failed to prepare clk\n");
> > + return ret;
> > + }
> > +
> > + data->clk_master = devm_clk_get(dev, "master");
> > + if (IS_ERR(data->clk_master))
> > + data->clk_master = NULL;
> > +
> > + ret = clk_prepare(data->clk_master);
> > + if (ret) {
> > + clk_unprepare(data->clk);
> > + dev_err(dev, "Failed to prepare master's clk\n");
> > + return ret;
> > + }
> > +
> > + data->runtime_active = !pm_runtime_enabled(dev);
> > +
> > rwlock_init(&data->lock);
> > INIT_LIST_HEAD(&data->node);
> >
> > @@ -625,6 +744,34 @@ static int __init exynos_sysmmu_probe(struct platform_device *pdev)
> > return ret;
> > }
> >
> > +#ifdef CONFIG_PM_SLEEP
> > +static int sysmmu_suspend(struct device *dev)
> > +{
> > + struct sysmmu_drvdata *data = dev_get_drvdata(dev);
> > + unsigned long flags;
> > + read_lock_irqsave(&data->lock, flags);
> > + if (is_sysmmu_active(data) &&
> > + (!pm_runtime_enabled(dev) || data->runtime_active))
> > + __sysmmu_disable_nocount(data);
> > + read_unlock_irqrestore(&data->lock, flags);
> > + return 0;
> > +}
> > +
> > +static int sysmmu_resume(struct device *dev)
> > +{
> > + struct sysmmu_drvdata *data = dev_get_drvdata(dev);
> > + unsigned long flags;
> > + read_lock_irqsave(&data->lock, flags);
> > + if (is_sysmmu_active(data) &&
> > + (!pm_runtime_enabled(dev) || data->runtime_active))
> > + __sysmmu_enable_nocount(data);
> > + read_unlock_irqrestore(&data->lock, flags);
> > + return 0;
> > +}
> > +#endif
> > +
> > +static SIMPLE_DEV_PM_OPS(sysmmu_pm_ops, sysmmu_suspend, sysmmu_resume);
> > +
> > #ifdef CONFIG_OF
> > static struct of_device_id sysmmu_of_match[] __initconst = {
> > { .compatible = "samsung,exynos4210-sysmmu", },
> > @@ -637,6 +784,7 @@ static struct platform_driver exynos_sysmmu_driver __refdata = {
> > .driver = {
> > .owner = THIS_MODULE,
> > .name = "exynos-sysmmu",
> > + .pm = &sysmmu_pm_ops,
> > .of_match_table = of_match_ptr(sysmmu_of_match),
> > }
> > };
> > @@ -689,7 +837,7 @@ err_pgtable:
> > static void exynos_iommu_domain_destroy(struct iommu_domain *domain)
> > {
> > struct exynos_iommu_domain *priv = domain->priv;
> > - struct sysmmu_drvdata *data;
> > + struct exynos_iommu_client *client;
> > unsigned long flags;
> > int i;
> >
> > @@ -697,11 +845,14 @@ static void exynos_iommu_domain_destroy(struct iommu_domain *domain)
> >
> > spin_lock_irqsave(&priv->lock, flags);
> >
> > - list_for_each_entry(data, &priv->clients, node) {
> > - while (!exynos_sysmmu_disable(data->dev))
> > + list_for_each_entry(client, &priv->clients, node) {
> > + while (!exynos_sysmmu_disable(client->dev))
> > ; /* until System MMU is actually disabled */
> > }
> >
> > + while (!list_empty(&priv->clients))
> > + list_del_init(priv->clients.next);
> > +
> > spin_unlock_irqrestore(&priv->lock, flags);
> >
> > for (i = 0; i < NUM_LV1ENTRIES; i++)
> > @@ -718,41 +869,26 @@ static void exynos_iommu_domain_destroy(struct iommu_domain *domain)
> > static int exynos_iommu_attach_device(struct iommu_domain *domain,
> > struct device *dev)
> > {
> > - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
> > + struct exynos_iommu_client *client = dev->archdata.iommu;
> > struct exynos_iommu_domain *priv = domain->priv;
> > unsigned long flags;
> > int ret;
> >
> > - ret = pm_runtime_get_sync(data->sysmmu);
> > - if (ret < 0)
> > - return ret;
> > -
> > - ret = 0;
> > -
> > spin_lock_irqsave(&priv->lock, flags);
> >
> > - ret = __exynos_sysmmu_enable(data, __pa(priv->pgtable), domain);
> > -
> > - if (ret == 0) {
> > - /* 'data->node' must not be appeared in priv->clients */
> > - BUG_ON(!list_empty(&data->node));
> > - data->dev = dev;
> > - list_add_tail(&data->node, &priv->clients);
> > - }
> > + ret = __exynos_sysmmu_enable(dev, __pa(priv->pgtable), domain);
> > + if (ret == 0)
> > + list_add_tail(&client->node, &priv->clients);
> >
> > spin_unlock_irqrestore(&priv->lock, flags);
> >
> > - if (ret < 0) {
> > + if (ret < 0)
> > dev_err(dev, "%s: Failed to attach IOMMU with pgtable %#lx\n",
> > __func__, __pa(priv->pgtable));
> > - pm_runtime_put(data->sysmmu);
> > - } else if (ret > 0) {
> > - dev_dbg(dev, "%s: IOMMU with pgtable 0x%lx already attached\n",
> > - __func__, __pa(priv->pgtable));
> > - } else {
> > - dev_dbg(dev, "%s: Attached new IOMMU with pgtable 0x%lx\n",
> > - __func__, __pa(priv->pgtable));
> > - }
> > + else
> > + dev_dbg(dev, "%s: Attached IOMMU with pgtable 0x%lx%s\n",
> > + __func__, __pa(priv->pgtable),
> > + (ret == 0) ? "" : ", again");
> >
> > return ret;
> > }
> > @@ -760,39 +896,27 @@ static int exynos_iommu_attach_device(struct iommu_domain *domain,
> > static void exynos_iommu_detach_device(struct iommu_domain *domain,
> > struct device *dev)
> > {
> > - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
> > + struct exynos_iommu_client *client = NULL;
> > struct exynos_iommu_domain *priv = domain->priv;
> > - struct list_head *pos;
> > unsigned long flags;
> > - bool found = false;
> >
> > spin_lock_irqsave(&priv->lock, flags);
> >
> > - list_for_each(pos, &priv->clients) {
> > - if (list_entry(pos, struct sysmmu_drvdata, node) == data) {
> > - found = true;
> > + list_for_each_entry(client, &priv->clients, node) {
> > + if (client == dev->archdata.iommu) {
> > + if (exynos_sysmmu_disable(dev))
> > + list_del_init(&client->node);
> > break;
> > }
> > }
> >
> > - if (!found)
> > - goto finish;
> > + spin_unlock_irqrestore(&priv->lock, flags);
> >
> > - if (__exynos_sysmmu_disable(data)) {
> > + if (client == dev->archdata.iommu)
> > dev_dbg(dev, "%s: Detached IOMMU with pgtable %#lx\n",
> > __func__, __pa(priv->pgtable));
> > - list_del_init(&data->node);
> > -
> > - } else {
> > - dev_dbg(dev, "%s: Detaching IOMMU with pgtable %#lx delayed",
> > - __func__, __pa(priv->pgtable));
> > - }
> > -
> > -finish:
> > - spin_unlock_irqrestore(&priv->lock, flags);
> > -
> > - if (found)
> > - pm_runtime_put(data->sysmmu);
> > + else
> > + dev_dbg(dev, "%s: No IOMMU is attached\n", __func__);
> > }
> >
> > static unsigned long *alloc_lv2entry(unsigned long *sent, unsigned long iova,
> > @@ -914,7 +1038,7 @@ static size_t exynos_iommu_unmap(struct iommu_domain *domain,
> > unsigned long iova, size_t size)
> > {
> > struct exynos_iommu_domain *priv = domain->priv;
> > - struct sysmmu_drvdata *data;
> > + struct exynos_iommu_client *client;
> > unsigned long flags;
> > unsigned long *ent;
> > size_t err_pgsize;
> > @@ -975,8 +1099,8 @@ done:
> > spin_unlock_irqrestore(&priv->pgtablelock, flags);
> >
> > spin_lock_irqsave(&priv->lock, flags);
> > - list_for_each_entry(data, &priv->clients, node)
> > - sysmmu_tlb_invalidate_entry(data->dev, iova);
> > + list_for_each_entry(client, &priv->clients, node)
> > + sysmmu_tlb_invalidate_entry(client->dev, iova);
> > spin_unlock_irqrestore(&priv->lock, flags);
> >
> > return size;
> > @@ -1055,3 +1179,275 @@ static int __init exynos_iommu_init(void)
> > return ret;
> > }
> > subsys_initcall(exynos_iommu_init);
> > +
> > +#ifdef CONFIG_PM_SLEEP
> > +static int sysmmu_pm_genpd_suspend(struct device *dev)
> > +{
> > + struct exynos_iommu_client *client = dev->archdata.iommu;
> > + int ret = 0;
> > + int i;
> > +
> > + for (i = 0; i < client->num_sysmmu; i++) {
> > + ret = pm_generic_suspend(client->sysmmu[i]);
> > + if (ret)
> > + break;
> > + }
> > +
> > + if (!ret)
> > + ret = pm_generic_suspend(dev);
> > +
> > + if (ret) {
> > + int j;
> > +
> > + for (j = 0; j < i; j++)
> > + pm_generic_resume(client->sysmmu[j]);
> > + }
> > +
> > + return ret;
> > +}
> > +
> > +static int sysmmu_pm_genpd_resume(struct device *dev)
> > +{
> > + struct exynos_iommu_client *client = dev->archdata.iommu;
> > + int ret = 0;
> > + int i;
> > +
> > + for (i = 0; i < client->num_sysmmu; i++) {
> > + ret = pm_generic_resume(client->sysmmu[i]);
> > + if (ret)
> > + break;
> > + }
> > +
> > + if (!ret)
> > + ret = pm_generic_resume(dev);
> > +
> > + if (ret) {
> > + int j;
> > +
> > + for (j = 0; j < i; j++)
> > + pm_generic_suspend(client->sysmmu[j]);
> > + }
> > +
> > + return ret;
> > +}
> > +#endif
> > +
> > +#ifdef CONFIG_PM_RUNTIME
> > +static void sysmmu_restore_state(struct device *sysmmu)
> > +{
> > + struct sysmmu_drvdata *data = dev_get_drvdata(sysmmu);
> > + unsigned long flags;
> > +
> > + spin_lock_irqsave(&data->lock, flags);
> > + data->runtime_active = true;
> > + if (is_sysmmu_active(data))
> > + __sysmmu_enable_nocount(data);
> > + spin_unlock_irqrestore(&data->lock, flags);
> > +}
> > +
> > +static void sysmmu_save_state(struct device *sysmmu)
> > +{
> > + struct sysmmu_drvdata *data = dev_get_drvdata(sysmmu);
> > + unsigned long flags;
> > +
> > + spin_lock_irqsave(&data->lock, flags);
> > + if (is_sysmmu_active(data))
> > + __sysmmu_disable_nocount(data);
> > + data->runtime_active = false;
> > + spin_unlock_irqrestore(&data->lock, flags);
> > +}
> > +
> > +static int sysmmu_pm_genpd_save_state(struct device *dev)
> > +{
> > + struct exynos_iommu_client *client = dev->archdata.iommu;
> > + int (*cb)(struct device *__dev);
> > + int i;
> > +
> > + if (dev->type && dev->type->pm)
> > + cb = dev->type->pm->runtime_suspend;
> > + else if (dev->class && dev->class->pm)
> > + cb = dev->class->pm->runtime_suspend;
> > + else if (dev->bus && dev->bus->pm)
> > + cb = dev->bus->pm->runtime_suspend;
> > + else
> > + cb = NULL;
> > +
> > + if (!cb && dev->driver && dev->driver->pm)
> > + cb = dev->driver->pm->runtime_suspend;
> > +
> > + if (cb) {
> > + int ret;
> > +
> > + ret = cb(dev);
> > + if (ret)
> > + return ret;
> > + }
> > +
> > + for (i = 0; i < client->num_sysmmu; i++)
> > + sysmmu_save_state(client->sysmmu[i]);
> > +
> > + return 0;
> > +}
> > +
> > +static int sysmmu_pm_genpd_restore_state(struct device *dev)
> > +{
> > + struct exynos_iommu_client *client = dev->archdata.iommu;
> > + int (*cb)(struct device *__dev);
> > + int i;
> > +
> > + if (dev->type && dev->type->pm)
> > + cb = dev->type->pm->runtime_resume;
> > + else if (dev->class && dev->class->pm)
> > + cb = dev->class->pm->runtime_resume;
> > + else if (dev->bus && dev->bus->pm)
> > + cb = dev->bus->pm->runtime_resume;
> > + else
> > + cb = NULL;
> > +
> > + if (!cb && dev->driver && dev->driver->pm)
> > + cb = dev->driver->pm->runtime_resume;
> > +
> > + for (i = 0; i < client->num_sysmmu; i++)
> > + sysmmu_restore_state(client->sysmmu[i]);
> > +
> > + if (cb) {
> > + int ret;
> > + ret = cb(dev);
> > + if (ret) {
> > + for (i = 0; i < client->num_sysmmu; i++)
> > + sysmmu_save_state(client->sysmmu[i]);
> > + return ret;
> > + }
> > + }
> > +
> > + return 0;
> > +}
> > +#endif
> > +
> > +#ifdef CONFIG_PM_GENERIC_DOMAINS
> > +struct gpd_dev_ops sysmmu_devpm_ops = {
> > +#ifdef CONFIG_PM_RUNTIME
> > + .save_state = &sysmmu_pm_genpd_save_state,
> > + .restore_state = &sysmmu_pm_genpd_restore_state,
> > +#endif
> > +#ifdef CONFIG_PM_SLEEP
> > + .suspend = &sysmmu_pm_genpd_suspend,
> > + .resume = &sysmmu_pm_genpd_resume,
> > +#endif
> > +};
> > +#endif /* CONFIG_PM_GENERIC_DOMAINS */
> > +
> > +static int sysmmu_hook_driver_register(struct notifier_block *nb,
> > + unsigned long val,
> > + void *p)
> > +{
> > + struct device *dev = p;
> > +
> > + switch (val) {
> > + case BUS_NOTIFY_BIND_DRIVER:
> > + {
> > + int i = 0;
> > + int size = 0;
>
> You can drop the initialization here. They are getting initialised
> before actual use.

Yes, it is basically right.
I just want to be convinced that the output argument to of_get_property()
is not referenced before initialization even though of_get_property()
does not reference to the argument, actually.

>
> > + const __be32 *phandle;
> > + struct exynos_iommu_client *client;
> > +
> > + phandle = of_get_property(dev->of_node, "iommu", &size);
> > + if (!phandle)
> > + break;
> > +
> > + size = size / sizeof(*phandle); /* number of elements */
> > +
> > + client = devm_kzalloc(dev, sizeof(*client) * size, GFP_KERNEL);
>
> You do not need to allocate memory of size "sizeof(*client) * size" ? It should
> always be sizeof(*client).

Oh. It is my fault.
It must be 'sizeof(*client) + size * sizeof(client->sysmmu[0])'.
It will be fixed.

>
> > + if (!client) {
> > + dev_err(dev, "No Memory for exynos_iommu_client\n");
> > + return -ENOMEM;
> > + }
> > +
> > + client->num_sysmmu = size;
> > + client->dev = dev;
> > + INIT_LIST_HEAD(&client->node);
> > + spin_lock_init(&client->lock);
> > +
> > + for (i = 0; i < size; i++) {
> > + struct device_node *np;
> > + struct platform_device *sysmmu;
> > +
> > + /* this always success: see above of_find_property() */
> > + np = of_parse_phandle(dev->of_node, "iommu", i);
> > +
> > + sysmmu = of_find_device_by_node(np);
> > + if (!sysmmu) {
> > + dev_err(dev,
> > + "sysmmu node '%s' is not found\n",
> > + np->name);
> > + break;
> > + }
> > +
> > + client->sysmmu[i] = &sysmmu->dev;
>
> Your array has space for single 'device *'. You should allocate memory to
> client->sysmmu before accessing indexes above 0.

As I commented above, enough size is allocated.

>
> As if now, It is not corrupting other's memory since you have allocated a
> much bigger chunk for your client pointer which is wrong IMO.

That is my fault :)
>
> regards,
> Rahul Sharma

Thank you.

Cho KyongHo.

>
> > + }
> > +
> > + if (i < size) {
> > + while (--i >= 0)
> > + of_node_put(client->sysmmu[i]->of_node);
> > + devm_kfree(dev, client);
> > + return -ENODEV;
> > + }
> > +
> > + i = pm_genpd_add_callbacks(dev, &sysmmu_devpm_ops, NULL);
> > + if (i && (i != -ENOSYS)) {
> > + dev_err(dev,
> > + "Failed to register 'dev_pm_ops' for iommu\n");
> > + devm_kfree(dev, client);
> > + return i;
> > + }
> > +
> > + dev->archdata.iommu = client;
> > + break;
> > + }
> > + case BUS_NOTIFY_BOUND_DRIVER:
> > + {
> > + struct exynos_iommu_client *client = dev->archdata.iommu;
> > + if (dev->archdata.iommu &&
> > + (!pm_runtime_enabled(dev) ||
> > + IS_ERR(dev_to_genpd(dev)))) {
> > + int i;
> > + for (i = 0; i < client->num_sysmmu; i++) {
> > + struct sysmmu_drvdata *data;
> > + pm_runtime_disable(client->sysmmu[i]);
> > + data = dev_get_drvdata(client->sysmmu[i]);
> > + if (!data)
> > + continue;
> > + data->runtime_active =
> > + !pm_runtime_enabled(data->sysmmu);
> > + if (data->runtime_active &&
> > + is_sysmmu_active(data))
> > + __sysmmu_enable_nocount(data);
> > + }
> > + }
> > + break;
> > + }
> > + case BUS_NOTIFY_UNBOUND_DRIVER:
> > + {
> > + if (dev->archdata.iommu) {
> > + __pm_genpd_remove_callbacks(dev, false);
> > +
> > + devm_kfree(dev, dev->archdata.iommu);
> > +
> > + dev->archdata.iommu = NULL;
> > + }
> > + break;
> > + }
> > + } /* switch (val) */
> > +
> > + return 0;
> > +}
> > +
> > +static struct notifier_block sysmmu_notifier = {
> > + .notifier_call = &sysmmu_hook_driver_register,
> > +};
> > +
> > +static int __init exynos_iommu_prepare(void)
> > +{
> > + return bus_register_notifier(&platform_bus_type, &sysmmu_notifier);
> > +}
> > +arch_initcall(exynos_iommu_prepare);
> > --
> > 1.7.2.5
> >
> >
> > _______________________________________________
> > iommu mailing list
> > [email protected]
> > https://lists.linuxfoundation.org/mailman/listinfo/iommu

2013-08-02 07:06:32

by Rahul Sharma

[permalink] [raw]
Subject: Re: [PATCH v8 10/12] iommu/exynos: add bus notifier for registering System MMU

On Fri, Aug 2, 2013 at 12:12 PM, Cho KyongHo <[email protected]> wrote:
>> -----Original Message-----
>> From: Rahul Sharma [mailto:[email protected]]
>> Sent: Friday, August 02, 2013 2:18 PM
>>
>> Hi Cho,
>>
>> On Fri, Jul 26, 2013 at 5:00 PM, Cho KyongHo <[email protected]> wrote:
>> > When a device driver is registered, all constructs to handle System MMU
>> > is prepared by bus notifier call.
>> >
>> > Signed-off-by: Cho KyongHo <[email protected]>
>> > ---
>> > drivers/iommu/exynos-iommu.c | 708 ++++++++++++++++++++++++++++++++---------
>> > 1 files changed, 552 insertions(+), 156 deletions(-)
>> >
>> > diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
>> > index f9853fe..c62c244 100644
>> > --- a/drivers/iommu/exynos-iommu.c
>> > +++ b/drivers/iommu/exynos-iommu.c
>> > @@ -27,6 +27,9 @@
>> > #include <linux/memblock.h>
>> > #include <linux/export.h>
>> > #include <linux/of.h>
>> > +#include <linux/of_platform.h>
>> > +#include <linux/pm_domain.h>
>> > +#include <linux/notifier.h>
>> >
>> > #include <asm/cacheflush.h>
>> > #include <asm/pgtable.h>
>> > @@ -80,7 +83,13 @@
>> > #define CTRL_BLOCK 0x7
>> > #define CTRL_DISABLE 0x0
>> >
>> > +#define CFG_LRU 0x1
>> > +#define CFG_QOS(n) ((n & 0xF) << 7)
>> > +#define CFG_MASK 0x0150FFFF /* Selecting bit 0-15, 20, 22 and 24 */
>> > +#define CFG_ACGEN (1 << 24) /* System MMU 3.3 only */
>> > +#define CFG_SYSSEL (1 << 22) /* System MMU 3.2 only */
>> > #define CFG_FLPDCACHE (1 << 20) /* System MMU 3.2+ only */
>> > +#define CFG_SHAREABLE (1 << 12) /* System MMU 3.x only */
>> >
>> > #define REG_MMU_CTRL 0x000
>> > #define REG_MMU_CFG 0x004
>> > @@ -154,6 +163,14 @@ static char *sysmmu_fault_name[SYSMMU_FAULTS_NUM] = {
>> > "UNKNOWN FAULT"
>> > };
>> >
>> > +struct exynos_iommu_client {
>> > + struct list_head node; /* entry of exynos_iommu_domain.clients */
>> > + struct device *dev;
>> > + spinlock_t lock;
>> > + int num_sysmmu;
>> > + struct device *sysmmu[0];
>>
>> Shouldn't we keep limit on the max number of iommu's to a single client ? Even
>> this way, you will hit array overrun with multiple iommu's.
>>
>
> I don't think it is needed to fix the size of the array because
> we know the size of the array in booting time.
> sysmmu[0] is just a placeholder of array.
>
>> > +};
>> > +
>> > struct exynos_iommu_domain {
>> > struct list_head clients; /* list of sysmmu_drvdata.node */
>> > unsigned long *pgtable; /* lv1 page table, 16KB */
>> > @@ -165,12 +182,14 @@ struct exynos_iommu_domain {
>> > struct sysmmu_drvdata {
>> > struct list_head node; /* entry of exynos_iommu_domain.clients */
>> > struct device *sysmmu; /* System MMU's device descriptor */
>> > - struct device *dev; /* Owner of system MMU */
>> > + struct device *master; /* Owner of system MMU */
>> > int nsfrs;
>> > struct clk *clk;
>> > + struct clk *clk_master;
>> > int activations;
>> > rwlock_t lock;
>> > struct iommu_domain *domain;
>> > + bool runtime_active;
>> > unsigned long pgtable;
>> > void __iomem *sfrbases[0];
>> > };
>> > @@ -245,7 +264,6 @@ static void __sysmmu_tlb_invalidate_entry(void __iomem *sfrbase,
>> > static void __sysmmu_set_ptbase(void __iomem *sfrbase,
>> > unsigned long pgd)
>> > {
>> > - __raw_writel(0x1, sfrbase + REG_MMU_CFG); /* 16KB LV1, LRU */
>> > __raw_writel(pgd, sfrbase + REG_PT_BASE_ADDR);
>> >
>> > __sysmmu_tlb_invalidate(sfrbase);
>> > @@ -273,6 +291,7 @@ void exynos_sysmmu_set_prefbuf(struct device *dev,
>> > if (!is_sysmmu_active(data))
>> > goto finish;
>> >
>> > + clk_enable(data->clk_master);
>> > for (i = 0; i < data->nsfrs; i++) {
>> > if ((readl(data->sfrbases[i] + REG_MMU_VERSION) >> 28) == 3) {
>> > if (!sysmmu_block(data->sfrbases[i]))
>> > @@ -298,6 +317,7 @@ void exynos_sysmmu_set_prefbuf(struct device *dev,
>> > sysmmu_unblock(data->sfrbases[i]);
>> > }
>> > }
>> > + clk_disable(data->clk_master);
>> > finish:
>> > read_unlock_irqrestore(&data->lock, flags);
>> > }
>> > @@ -331,12 +351,13 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
>> > {
>> > /* SYSMMU is in blocked when interrupt occurred. */
>> > struct sysmmu_drvdata *data = dev_id;
>> > + struct exynos_iommu_client *client = NULL;
>> > enum exynos_sysmmu_inttype itype;
>> > unsigned long addr = -1;
>> > -
>> > int i, ret = -ENOSYS;
>> >
>> > - read_lock(&data->lock);
>> > + if (data->master)
>> > + client = data->master->archdata.iommu;
>> >
>> > WARN_ON(!is_sysmmu_active(data));
>> >
>> > @@ -348,6 +369,10 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
>> > break;
>> > }
>> >
>> > + if (client)
>> > + spin_lock(&client->lock);
>> > + read_lock(&data->lock);
>> > +
>> > if (i == data->nsfrs) {
>> > itype = SYSMMU_FAULT_UNKNOWN;
>> > } else {
>> > @@ -361,7 +386,7 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
>> > }
>> >
>> > if (data->domain)
>> > - ret = report_iommu_fault(data->domain, data->dev,
>> > + ret = report_iommu_fault(data->domain, data->master,
>> > addr, itype);
>> >
>> > if (!ret && (itype != SYSMMU_FAULT_UNKNOWN))
>> > @@ -378,177 +403,251 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
>> > sysmmu_unblock(data->sfrbases[i]);
>> >
>> > read_unlock(&data->lock);
>> > + if (client)
>> > + spin_unlock(&client->lock);
>> >
>> > return IRQ_HANDLED;
>> > }
>> >
>> > -static bool __exynos_sysmmu_disable(struct sysmmu_drvdata *data)
>> > +static void __sysmmu_disable_nocount(struct sysmmu_drvdata *data)
>> > {
>> > - unsigned long flags;
>> > - bool disabled = false;
>> > int i;
>> >
>> > - write_lock_irqsave(&data->lock, flags);
>> > + clk_enable(data->clk_master);
>> > + for (i = 0; i < data->nsfrs; i++) {
>> > + __raw_writel(CTRL_DISABLE,
>> > + data->sfrbases[i] + REG_MMU_CTRL);
>> > + __raw_writel(0, data->sfrbases[i] + REG_MMU_CFG);
>> > + }
>> >
>> > - if (!set_sysmmu_inactive(data))
>> > - goto finish;
>> > + clk_disable(data->clk);
>> > + clk_disable(data->clk_master);
>> > +}
>> >
>> > - for (i = 0; i < data->nsfrs; i++)
>> > - __raw_writel(CTRL_DISABLE, data->sfrbases[i] + REG_MMU_CTRL);
>> > +static bool __sysmmu_disable(struct sysmmu_drvdata *data)
>> > +{
>> > + bool disabled;
>> > + unsigned long flags;
>> >
>> > - if (data->clk)
>> > - clk_disable(data->clk);
>> > + write_lock_irqsave(&data->lock, flags);
>> >
>> > - disabled = true;
>> > - data->pgtable = 0;
>> > - data->domain = NULL;
>> > -finish:
>> > - write_unlock_irqrestore(&data->lock, flags);
>> > + disabled = set_sysmmu_inactive(data);
>> > +
>> > + if (disabled) {
>> > + data->pgtable = 0;
>> > + data->domain = NULL;
>> > +
>> > + if (data->runtime_active)
>> > + __sysmmu_disable_nocount(data);
>> >
>> > - if (disabled)
>> > dev_dbg(data->sysmmu, "Disabled\n");
>> > - else
>> > - dev_dbg(data->sysmmu, "%d times left to be disabled\n",
>> > + } else {
>> > + dev_dbg(data->sysmmu, "%d times left to disable\n",
>> > data->activations);
>> > + }
>> > +
>> > + write_unlock_irqrestore(&data->lock, flags);
>> >
>> > return disabled;
>> > }
>> >
>> > -/* __exynos_sysmmu_enable: Enables System MMU
>> > - *
>> > - * returns -error if an error occurred and System MMU is not enabled,
>> > - * 0 if the System MMU has been just enabled and 1 if System MMU was already
>> > - * enabled before.
>> > - */
>> > -static int __exynos_sysmmu_enable(struct sysmmu_drvdata *data,
>> > +
>> > +static void __sysmmu_init_config(struct sysmmu_drvdata *data, int idx)
>> > +{
>> > + unsigned long cfg = CFG_LRU | CFG_QOS(15);
>> > + int maj, min = 0;
>> > +
>> > + maj = __sysmmu_version(data, idx, &min);
>> > + if (maj == 3) {
>> > + if (min > 1) {
>> > + cfg |= CFG_FLPDCACHE;
>> > + cfg |= (min == 2) ? CFG_SYSSEL : CFG_ACGEN;
>> > + }
>> > + }
>> > +
>> > + __raw_writel(cfg, data->sfrbases[idx] + REG_MMU_CFG);
>> > +}
>> > +
>> > +static void __sysmmu_enable_nocount(struct sysmmu_drvdata *data)
>> > +{
>> > + int i;
>> > +
>> > + clk_enable(data->clk_master);
>> > + clk_enable(data->clk);
>> > +
>> > + for (i = 0; i < data->nsfrs; i++) {
>> > + __raw_writel(CTRL_BLOCK, data->sfrbases[i] + REG_MMU_CTRL);
>> > +
>> > + __sysmmu_init_config(data, i);
>> > +
>> > + __sysmmu_set_ptbase(data->sfrbases[i], data->pgtable);
>> > +
>> > + __raw_writel(CTRL_ENABLE, data->sfrbases[i] + REG_MMU_CTRL);
>> > + }
>> > + clk_disable(data->clk_master);
>> > +}
>> > +
>> > +static int __sysmmu_enable(struct sysmmu_drvdata *data,
>> > unsigned long pgtable, struct iommu_domain *domain)
>> > {
>> > - int i, ret = 0;
>> > + int ret = 0;
>> > unsigned long flags;
>> >
>> > write_lock_irqsave(&data->lock, flags);
>> > + if (set_sysmmu_active(data)) {
>> > + data->pgtable = pgtable;
>> > + data->domain = domain;
>> >
>> > - if (!set_sysmmu_active(data)) {
>> > - if (WARN_ON(pgtable != data->pgtable)) {
>> > - ret = -EBUSY;
>> > - set_sysmmu_inactive(data);
>> > - } else {
>> > - ret = 1;
>> > - }
>> > + if (data->runtime_active)
>> > + __sysmmu_enable_nocount(data);
>> >
>> > - dev_dbg(data->sysmmu, "Already enabled\n");
>> > - goto finish;
>> > + dev_dbg(data->sysmmu, "Enabled\n");
>> > + } else {
>> > + ret = (pgtable == data->pgtable) ? 1 : -EBUSY;
>> > +
>> > + dev_dbg(data->sysmmu, "already enabled\n");
>> > }
>> >
>> > - if (data->clk)
>> > - clk_enable(data->clk);
>> > + if (WARN_ON(ret < 0))
>> > + set_sysmmu_inactive(data); /* decrement count */
>> >
>> > - data->pgtable = pgtable;
>> > + write_unlock_irqrestore(&data->lock, flags);
>> >
>> > - for (i = 0; i < data->nsfrs; i++) {
>> > - unsigned int min;
>> > + return ret;
>> > +}
>> >
>> > - __sysmmu_set_ptbase(data->sfrbases[i], pgtable);
>> > +/* __exynos_sysmmu_enable: Enables System MMU
>> > + *
>> > + * returns -error if an error occurred and System MMU is not enabled,
>> > + * 0 if the System MMU has been just enabled and 1 if System MMU was already
>> > + * enabled before.
>> > + */
>> > +static int __exynos_sysmmu_enable(struct device *dev, unsigned long pgtable,
>> > + struct iommu_domain *domain)
>> > +{
>> > + int ret = 0;
>> > + unsigned long flags;
>> > + struct exynos_iommu_client *client = dev->archdata.iommu;
>> > + int i;
>> >
>> > - if ((__sysmmu_version(data, i, &min) == 3) && (min > 1)) {
>> > - unsigned long cfg;
>> > - cfg = __raw_readl(data->sfrbases[i] + REG_MMU_CFG);
>> > - __raw_writel(cfg | CFG_FLPDCACHE,
>> > - data->sfrbases[i] + REG_MMU_CFG);
>> > - }
>> > + if (WARN_ON(!client))
>> > + return -ENODEV;
>> >
>> > - __raw_writel(CTRL_ENABLE, data->sfrbases[i] + REG_MMU_CTRL);
>> > - }
>> > + spin_lock_irqsave(&client->lock, flags);
>> >
>> > - data->domain = domain;
>> > + for (i = 0; i < client->num_sysmmu; i++) {
>> > + struct sysmmu_drvdata *data =
>> > + dev_get_drvdata(client->sysmmu[i]);
>> > + ret = __sysmmu_enable(data, pgtable, domain);
>> > + if (ret < 0) {
>> > + int j;
>> > + for (j = 0; j < i; j++)
>> > + __sysmmu_disable(data);
>> > + break;
>> > + } else {
>> > + data->master = dev;
>> > + }
>> > + }
>> >
>> > - dev_dbg(data->sysmmu, "Enabled\n");
>> > -finish:
>> > - write_unlock_irqrestore(&data->lock, flags);
>> > + spin_unlock_irqrestore(&client->lock, flags);
>> >
>> > return ret;
>> > }
>> >
>> > int exynos_sysmmu_enable(struct device *dev, unsigned long pgtable)
>> > {
>> > - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
>> > int ret;
>> >
>> > BUG_ON(!memblock_is_memory(pgtable));
>> >
>> > - ret = pm_runtime_get_sync(data->sysmmu);
>> > - if (ret < 0) {
>> > - dev_dbg(data->sysmmu, "Failed to enable\n");
>> > - return ret;
>> > - }
>> > -
>> > - ret = __exynos_sysmmu_enable(data, pgtable, NULL);
>> > - if (WARN_ON(ret < 0)) {
>> > - pm_runtime_put(data->sysmmu);
>> > - dev_err(data->sysmmu,
>> > - "Already enabled with page table %#lx\n",
>> > - data->pgtable);
>> > - } else {
>> > - data->dev = dev;
>> > - }
>> > + ret = __exynos_sysmmu_enable(dev, pgtable, NULL);
>> >
>> > return ret;
>> > }
>> >
>> > static bool exynos_sysmmu_disable(struct device *dev)
>> > {
>> > - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
>> > - bool disabled;
>> > + unsigned long flags;
>> > + bool disabled = true;
>> > + struct exynos_iommu_client *client = dev->archdata.iommu;
>> > + int i;
>> >
>> > - disabled = __exynos_sysmmu_disable(data);
>> > - pm_runtime_put(data->sysmmu);
>> > + if (WARN_ON(!client))
>> > + return true;
>> > +
>> > + spin_lock_irqsave(&client->lock, flags);
>> > +
>> > + /* Every call to __sysmmu_disable() must return same result */
>> > + for (i = 0; i < client->num_sysmmu; i++) {
>> > + struct sysmmu_drvdata *data =
>> > + dev_get_drvdata(client->sysmmu[i]);
>> > + disabled = __sysmmu_disable(data);
>> > + if (disabled)
>> > + data->master = NULL;
>> > + }
>> > +
>> > + spin_unlock_irqrestore(&client->lock, flags);
>> >
>> > return disabled;
>> > }
>> >
>> > static void sysmmu_tlb_invalidate_entry(struct device *dev, unsigned long iova)
>> > {
>> > - unsigned long flags;
>> > - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
>> > + struct exynos_iommu_client *client = dev->archdata.iommu;
>> > + int i;
>> >
>> > - read_lock_irqsave(&data->lock, flags);
>> > + for (i = 0; i < client->num_sysmmu; i++) {
>> > + unsigned long flags;
>> > + struct sysmmu_drvdata *data;
>> >
>> > - if (is_sysmmu_active(data)) {
>> > - int i;
>> > - for (i = 0; i < data->nsfrs; i++) {
>> > - if (sysmmu_block(data->sfrbases[i])) {
>> > + data = dev_get_drvdata(client->sysmmu[i]);
>> > +
>> > + read_lock_irqsave(&data->lock, flags);
>> > + if (is_sysmmu_active(data) && data->runtime_active) {
>> > + int i;
>> > + clk_enable(data->clk_master);
>> > + for (i = 0; i < data->nsfrs; i++)
>> > __sysmmu_tlb_invalidate_entry(
>> > data->sfrbases[i], iova);
>> > - sysmmu_unblock(data->sfrbases[i]);
>> > - }
>> > + clk_disable(data->clk_master);
>> > + } else {
>> > + dev_dbg(dev,
>> > + "disabled. Skipping TLB invalidation @ %#lx\n",
>> > + iova);
>> > }
>> > - } else {
>> > - dev_dbg(data->sysmmu, "Disabled. Skipping invalidating TLB.\n");
>> > + read_unlock_irqrestore(&data->lock, flags);
>> > }
>> > -
>> > - read_unlock_irqrestore(&data->lock, flags);
>> > }
>> >
>> > void exynos_sysmmu_tlb_invalidate(struct device *dev)
>> > {
>> > - unsigned long flags;
>> > - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
>> > -
>> > - read_lock_irqsave(&data->lock, flags);
>> > + struct exynos_iommu_client *client = dev->archdata.iommu;
>> > + int i;
>> >
>> > - if (is_sysmmu_active(data)) {
>> > - int i;
>> > - for (i = 0; i < data->nsfrs; i++) {
>> > - if (sysmmu_block(data->sfrbases[i])) {
>> > - __sysmmu_tlb_invalidate(data->sfrbases[i]);
>> > - sysmmu_unblock(data->sfrbases[i]);
>> > + for (i = 0; i < client->num_sysmmu; i++) {
>> > + unsigned long flags;
>> > + struct sysmmu_drvdata *data;
>> > +
>> > + data = dev_get_drvdata(client->sysmmu[i]);
>> > +
>> > + read_lock_irqsave(&data->lock, flags);
>> > + if (is_sysmmu_active(data) &&
>> > + data->runtime_active) {
>> > + int i;
>> > + for (i = 0; i < data->nsfrs; i++) {
>> > + clk_enable(data->clk_master);
>> > + if (sysmmu_block(data->sfrbases[i])) {
>> > + __sysmmu_tlb_invalidate(
>> > + data->sfrbases[i]);
>> > + sysmmu_unblock(data->sfrbases[i]);
>> > + }
>> > + clk_disable(data->clk_master);
>> > }
>> > + } else {
>> > + dev_dbg(dev, "disabled. Skipping TLB invalidation\n");
>> > }
>> > - } else {
>> > - dev_dbg(data->sysmmu, "Disabled. Skipping invalidating TLB.\n");
>> > + read_unlock_irqrestore(&data->lock, flags);
>> > }
>> > -
>> > - read_unlock_irqrestore(&data->lock, flags);
>> > }
>> >
>> > static int __init exynos_sysmmu_probe(struct platform_device *pdev)
>> > @@ -610,12 +709,32 @@ static int __init exynos_sysmmu_probe(struct platform_device *pdev)
>> > pm_runtime_enable(dev);
>> >
>> > data->sysmmu = dev;
>> > +
>> > data->clk = devm_clk_get(dev, "sysmmu");
>> > if (IS_ERR(data->clk)) {
>> > dev_info(dev, "No gate clock found!\n");
>> > data->clk = NULL;
>> > }
>> >
>> > + ret = clk_prepare(data->clk);
>> > + if (ret) {
>> > + dev_err(dev, "Failed to prepare clk\n");
>> > + return ret;
>> > + }
>> > +
>> > + data->clk_master = devm_clk_get(dev, "master");
>> > + if (IS_ERR(data->clk_master))
>> > + data->clk_master = NULL;
>> > +
>> > + ret = clk_prepare(data->clk_master);
>> > + if (ret) {
>> > + clk_unprepare(data->clk);
>> > + dev_err(dev, "Failed to prepare master's clk\n");
>> > + return ret;
>> > + }
>> > +
>> > + data->runtime_active = !pm_runtime_enabled(dev);
>> > +
>> > rwlock_init(&data->lock);
>> > INIT_LIST_HEAD(&data->node);
>> >
>> > @@ -625,6 +744,34 @@ static int __init exynos_sysmmu_probe(struct platform_device *pdev)
>> > return ret;
>> > }
>> >
>> > +#ifdef CONFIG_PM_SLEEP
>> > +static int sysmmu_suspend(struct device *dev)
>> > +{
>> > + struct sysmmu_drvdata *data = dev_get_drvdata(dev);
>> > + unsigned long flags;
>> > + read_lock_irqsave(&data->lock, flags);
>> > + if (is_sysmmu_active(data) &&
>> > + (!pm_runtime_enabled(dev) || data->runtime_active))
>> > + __sysmmu_disable_nocount(data);
>> > + read_unlock_irqrestore(&data->lock, flags);
>> > + return 0;
>> > +}
>> > +
>> > +static int sysmmu_resume(struct device *dev)
>> > +{
>> > + struct sysmmu_drvdata *data = dev_get_drvdata(dev);
>> > + unsigned long flags;
>> > + read_lock_irqsave(&data->lock, flags);
>> > + if (is_sysmmu_active(data) &&
>> > + (!pm_runtime_enabled(dev) || data->runtime_active))
>> > + __sysmmu_enable_nocount(data);
>> > + read_unlock_irqrestore(&data->lock, flags);
>> > + return 0;
>> > +}
>> > +#endif
>> > +
>> > +static SIMPLE_DEV_PM_OPS(sysmmu_pm_ops, sysmmu_suspend, sysmmu_resume);
>> > +
>> > #ifdef CONFIG_OF
>> > static struct of_device_id sysmmu_of_match[] __initconst = {
>> > { .compatible = "samsung,exynos4210-sysmmu", },
>> > @@ -637,6 +784,7 @@ static struct platform_driver exynos_sysmmu_driver __refdata = {
>> > .driver = {
>> > .owner = THIS_MODULE,
>> > .name = "exynos-sysmmu",
>> > + .pm = &sysmmu_pm_ops,
>> > .of_match_table = of_match_ptr(sysmmu_of_match),
>> > }
>> > };
>> > @@ -689,7 +837,7 @@ err_pgtable:
>> > static void exynos_iommu_domain_destroy(struct iommu_domain *domain)
>> > {
>> > struct exynos_iommu_domain *priv = domain->priv;
>> > - struct sysmmu_drvdata *data;
>> > + struct exynos_iommu_client *client;
>> > unsigned long flags;
>> > int i;
>> >
>> > @@ -697,11 +845,14 @@ static void exynos_iommu_domain_destroy(struct iommu_domain *domain)
>> >
>> > spin_lock_irqsave(&priv->lock, flags);
>> >
>> > - list_for_each_entry(data, &priv->clients, node) {
>> > - while (!exynos_sysmmu_disable(data->dev))
>> > + list_for_each_entry(client, &priv->clients, node) {
>> > + while (!exynos_sysmmu_disable(client->dev))
>> > ; /* until System MMU is actually disabled */
>> > }
>> >
>> > + while (!list_empty(&priv->clients))
>> > + list_del_init(priv->clients.next);
>> > +
>> > spin_unlock_irqrestore(&priv->lock, flags);
>> >
>> > for (i = 0; i < NUM_LV1ENTRIES; i++)
>> > @@ -718,41 +869,26 @@ static void exynos_iommu_domain_destroy(struct iommu_domain *domain)
>> > static int exynos_iommu_attach_device(struct iommu_domain *domain,
>> > struct device *dev)
>> > {
>> > - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
>> > + struct exynos_iommu_client *client = dev->archdata.iommu;
>> > struct exynos_iommu_domain *priv = domain->priv;
>> > unsigned long flags;
>> > int ret;
>> >
>> > - ret = pm_runtime_get_sync(data->sysmmu);
>> > - if (ret < 0)
>> > - return ret;
>> > -
>> > - ret = 0;
>> > -
>> > spin_lock_irqsave(&priv->lock, flags);
>> >
>> > - ret = __exynos_sysmmu_enable(data, __pa(priv->pgtable), domain);
>> > -
>> > - if (ret == 0) {
>> > - /* 'data->node' must not be appeared in priv->clients */
>> > - BUG_ON(!list_empty(&data->node));
>> > - data->dev = dev;
>> > - list_add_tail(&data->node, &priv->clients);
>> > - }
>> > + ret = __exynos_sysmmu_enable(dev, __pa(priv->pgtable), domain);
>> > + if (ret == 0)
>> > + list_add_tail(&client->node, &priv->clients);
>> >
>> > spin_unlock_irqrestore(&priv->lock, flags);
>> >
>> > - if (ret < 0) {
>> > + if (ret < 0)
>> > dev_err(dev, "%s: Failed to attach IOMMU with pgtable %#lx\n",
>> > __func__, __pa(priv->pgtable));
>> > - pm_runtime_put(data->sysmmu);
>> > - } else if (ret > 0) {
>> > - dev_dbg(dev, "%s: IOMMU with pgtable 0x%lx already attached\n",
>> > - __func__, __pa(priv->pgtable));
>> > - } else {
>> > - dev_dbg(dev, "%s: Attached new IOMMU with pgtable 0x%lx\n",
>> > - __func__, __pa(priv->pgtable));
>> > - }
>> > + else
>> > + dev_dbg(dev, "%s: Attached IOMMU with pgtable 0x%lx%s\n",
>> > + __func__, __pa(priv->pgtable),
>> > + (ret == 0) ? "" : ", again");
>> >
>> > return ret;
>> > }
>> > @@ -760,39 +896,27 @@ static int exynos_iommu_attach_device(struct iommu_domain *domain,
>> > static void exynos_iommu_detach_device(struct iommu_domain *domain,
>> > struct device *dev)
>> > {
>> > - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
>> > + struct exynos_iommu_client *client = NULL;
>> > struct exynos_iommu_domain *priv = domain->priv;
>> > - struct list_head *pos;
>> > unsigned long flags;
>> > - bool found = false;
>> >
>> > spin_lock_irqsave(&priv->lock, flags);
>> >
>> > - list_for_each(pos, &priv->clients) {
>> > - if (list_entry(pos, struct sysmmu_drvdata, node) == data) {
>> > - found = true;
>> > + list_for_each_entry(client, &priv->clients, node) {
>> > + if (client == dev->archdata.iommu) {
>> > + if (exynos_sysmmu_disable(dev))
>> > + list_del_init(&client->node);
>> > break;
>> > }
>> > }
>> >
>> > - if (!found)
>> > - goto finish;
>> > + spin_unlock_irqrestore(&priv->lock, flags);
>> >
>> > - if (__exynos_sysmmu_disable(data)) {
>> > + if (client == dev->archdata.iommu)
>> > dev_dbg(dev, "%s: Detached IOMMU with pgtable %#lx\n",
>> > __func__, __pa(priv->pgtable));
>> > - list_del_init(&data->node);
>> > -
>> > - } else {
>> > - dev_dbg(dev, "%s: Detaching IOMMU with pgtable %#lx delayed",
>> > - __func__, __pa(priv->pgtable));
>> > - }
>> > -
>> > -finish:
>> > - spin_unlock_irqrestore(&priv->lock, flags);
>> > -
>> > - if (found)
>> > - pm_runtime_put(data->sysmmu);
>> > + else
>> > + dev_dbg(dev, "%s: No IOMMU is attached\n", __func__);
>> > }
>> >
>> > static unsigned long *alloc_lv2entry(unsigned long *sent, unsigned long iova,
>> > @@ -914,7 +1038,7 @@ static size_t exynos_iommu_unmap(struct iommu_domain *domain,
>> > unsigned long iova, size_t size)
>> > {
>> > struct exynos_iommu_domain *priv = domain->priv;
>> > - struct sysmmu_drvdata *data;
>> > + struct exynos_iommu_client *client;
>> > unsigned long flags;
>> > unsigned long *ent;
>> > size_t err_pgsize;
>> > @@ -975,8 +1099,8 @@ done:
>> > spin_unlock_irqrestore(&priv->pgtablelock, flags);
>> >
>> > spin_lock_irqsave(&priv->lock, flags);
>> > - list_for_each_entry(data, &priv->clients, node)
>> > - sysmmu_tlb_invalidate_entry(data->dev, iova);
>> > + list_for_each_entry(client, &priv->clients, node)
>> > + sysmmu_tlb_invalidate_entry(client->dev, iova);
>> > spin_unlock_irqrestore(&priv->lock, flags);
>> >
>> > return size;
>> > @@ -1055,3 +1179,275 @@ static int __init exynos_iommu_init(void)
>> > return ret;
>> > }
>> > subsys_initcall(exynos_iommu_init);
>> > +
>> > +#ifdef CONFIG_PM_SLEEP
>> > +static int sysmmu_pm_genpd_suspend(struct device *dev)
>> > +{
>> > + struct exynos_iommu_client *client = dev->archdata.iommu;
>> > + int ret = 0;
>> > + int i;
>> > +
>> > + for (i = 0; i < client->num_sysmmu; i++) {
>> > + ret = pm_generic_suspend(client->sysmmu[i]);
>> > + if (ret)
>> > + break;
>> > + }
>> > +
>> > + if (!ret)
>> > + ret = pm_generic_suspend(dev);
>> > +
>> > + if (ret) {
>> > + int j;
>> > +
>> > + for (j = 0; j < i; j++)
>> > + pm_generic_resume(client->sysmmu[j]);
>> > + }
>> > +
>> > + return ret;
>> > +}
>> > +
>> > +static int sysmmu_pm_genpd_resume(struct device *dev)
>> > +{
>> > + struct exynos_iommu_client *client = dev->archdata.iommu;
>> > + int ret = 0;
>> > + int i;
>> > +
>> > + for (i = 0; i < client->num_sysmmu; i++) {
>> > + ret = pm_generic_resume(client->sysmmu[i]);
>> > + if (ret)
>> > + break;
>> > + }
>> > +
>> > + if (!ret)
>> > + ret = pm_generic_resume(dev);
>> > +
>> > + if (ret) {
>> > + int j;
>> > +
>> > + for (j = 0; j < i; j++)
>> > + pm_generic_suspend(client->sysmmu[j]);
>> > + }
>> > +
>> > + return ret;
>> > +}
>> > +#endif
>> > +
>> > +#ifdef CONFIG_PM_RUNTIME
>> > +static void sysmmu_restore_state(struct device *sysmmu)
>> > +{
>> > + struct sysmmu_drvdata *data = dev_get_drvdata(sysmmu);
>> > + unsigned long flags;
>> > +
>> > + spin_lock_irqsave(&data->lock, flags);
>> > + data->runtime_active = true;
>> > + if (is_sysmmu_active(data))
>> > + __sysmmu_enable_nocount(data);
>> > + spin_unlock_irqrestore(&data->lock, flags);
>> > +}
>> > +
>> > +static void sysmmu_save_state(struct device *sysmmu)
>> > +{
>> > + struct sysmmu_drvdata *data = dev_get_drvdata(sysmmu);
>> > + unsigned long flags;
>> > +
>> > + spin_lock_irqsave(&data->lock, flags);
>> > + if (is_sysmmu_active(data))
>> > + __sysmmu_disable_nocount(data);
>> > + data->runtime_active = false;
>> > + spin_unlock_irqrestore(&data->lock, flags);
>> > +}
>> > +
>> > +static int sysmmu_pm_genpd_save_state(struct device *dev)
>> > +{
>> > + struct exynos_iommu_client *client = dev->archdata.iommu;
>> > + int (*cb)(struct device *__dev);
>> > + int i;
>> > +
>> > + if (dev->type && dev->type->pm)
>> > + cb = dev->type->pm->runtime_suspend;
>> > + else if (dev->class && dev->class->pm)
>> > + cb = dev->class->pm->runtime_suspend;
>> > + else if (dev->bus && dev->bus->pm)
>> > + cb = dev->bus->pm->runtime_suspend;
>> > + else
>> > + cb = NULL;
>> > +
>> > + if (!cb && dev->driver && dev->driver->pm)
>> > + cb = dev->driver->pm->runtime_suspend;
>> > +
>> > + if (cb) {
>> > + int ret;
>> > +
>> > + ret = cb(dev);
>> > + if (ret)
>> > + return ret;
>> > + }
>> > +
>> > + for (i = 0; i < client->num_sysmmu; i++)
>> > + sysmmu_save_state(client->sysmmu[i]);
>> > +
>> > + return 0;
>> > +}
>> > +
>> > +static int sysmmu_pm_genpd_restore_state(struct device *dev)
>> > +{
>> > + struct exynos_iommu_client *client = dev->archdata.iommu;
>> > + int (*cb)(struct device *__dev);
>> > + int i;
>> > +
>> > + if (dev->type && dev->type->pm)
>> > + cb = dev->type->pm->runtime_resume;
>> > + else if (dev->class && dev->class->pm)
>> > + cb = dev->class->pm->runtime_resume;
>> > + else if (dev->bus && dev->bus->pm)
>> > + cb = dev->bus->pm->runtime_resume;
>> > + else
>> > + cb = NULL;
>> > +
>> > + if (!cb && dev->driver && dev->driver->pm)
>> > + cb = dev->driver->pm->runtime_resume;
>> > +
>> > + for (i = 0; i < client->num_sysmmu; i++)
>> > + sysmmu_restore_state(client->sysmmu[i]);
>> > +
>> > + if (cb) {
>> > + int ret;
>> > + ret = cb(dev);
>> > + if (ret) {
>> > + for (i = 0; i < client->num_sysmmu; i++)
>> > + sysmmu_save_state(client->sysmmu[i]);
>> > + return ret;
>> > + }
>> > + }
>> > +
>> > + return 0;
>> > +}
>> > +#endif
>> > +
>> > +#ifdef CONFIG_PM_GENERIC_DOMAINS
>> > +struct gpd_dev_ops sysmmu_devpm_ops = {
>> > +#ifdef CONFIG_PM_RUNTIME
>> > + .save_state = &sysmmu_pm_genpd_save_state,
>> > + .restore_state = &sysmmu_pm_genpd_restore_state,
>> > +#endif
>> > +#ifdef CONFIG_PM_SLEEP
>> > + .suspend = &sysmmu_pm_genpd_suspend,
>> > + .resume = &sysmmu_pm_genpd_resume,
>> > +#endif
>> > +};
>> > +#endif /* CONFIG_PM_GENERIC_DOMAINS */
>> > +
>> > +static int sysmmu_hook_driver_register(struct notifier_block *nb,
>> > + unsigned long val,
>> > + void *p)
>> > +{
>> > + struct device *dev = p;
>> > +
>> > + switch (val) {
>> > + case BUS_NOTIFY_BIND_DRIVER:
>> > + {
>> > + int i = 0;
>> > + int size = 0;
>>
>> You can drop the initialization here. They are getting initialised
>> before actual use.
>
> Yes, it is basically right.
> I just want to be convinced that the output argument to of_get_property()
> is not referenced before initialization even though of_get_property()
> does not reference to the argument, actually.
>

This is not wrong but I found it optional since you are already checking
for phandle. No problem.

>>
>> > + const __be32 *phandle;
>> > + struct exynos_iommu_client *client;
>> > +
>> > + phandle = of_get_property(dev->of_node, "iommu", &size);
>> > + if (!phandle)
>> > + break;
>> > +
>> > + size = size / sizeof(*phandle); /* number of elements */
>> > +
>> > + client = devm_kzalloc(dev, sizeof(*client) * size, GFP_KERNEL);
>>
>> You do not need to allocate memory of size "sizeof(*client) * size" ? It should
>> always be sizeof(*client).
>
> Oh. It is my fault.
> It must be 'sizeof(*client) + size * sizeof(client->sysmmu[0])'.
> It will be fixed.
>

sure.

Regards,
Rahul Sharma.

>>
>> > + if (!client) {
>> > + dev_err(dev, "No Memory for exynos_iommu_client\n");
>> > + return -ENOMEM;
>> > + }
>> > +
>> > + client->num_sysmmu = size;
>> > + client->dev = dev;
>> > + INIT_LIST_HEAD(&client->node);
>> > + spin_lock_init(&client->lock);
>> > +
>> > + for (i = 0; i < size; i++) {
>> > + struct device_node *np;
>> > + struct platform_device *sysmmu;
>> > +
>> > + /* this always success: see above of_find_property() */
>> > + np = of_parse_phandle(dev->of_node, "iommu", i);
>> > +
>> > + sysmmu = of_find_device_by_node(np);
>> > + if (!sysmmu) {
>> > + dev_err(dev,
>> > + "sysmmu node '%s' is not found\n",
>> > + np->name);
>> > + break;
>> > + }
>> > +
>> > + client->sysmmu[i] = &sysmmu->dev;
>>
>> Your array has space for single 'device *'. You should allocate memory to
>> client->sysmmu before accessing indexes above 0.
>
> As I commented above, enough size is allocated.
>
>>
>> As if now, It is not corrupting other's memory since you have allocated a
>> much bigger chunk for your client pointer which is wrong IMO.
>
> That is my fault :)
>>
>> regards,
>> Rahul Sharma
>
> Thank you.
>
> Cho KyongHo.
>
>>
>> > + }
>> > +
>> > + if (i < size) {
>> > + while (--i >= 0)
>> > + of_node_put(client->sysmmu[i]->of_node);
>> > + devm_kfree(dev, client);
>> > + return -ENODEV;
>> > + }
>> > +
>> > + i = pm_genpd_add_callbacks(dev, &sysmmu_devpm_ops, NULL);
>> > + if (i && (i != -ENOSYS)) {
>> > + dev_err(dev,
>> > + "Failed to register 'dev_pm_ops' for iommu\n");
>> > + devm_kfree(dev, client);
>> > + return i;
>> > + }
>> > +
>> > + dev->archdata.iommu = client;
>> > + break;
>> > + }
>> > + case BUS_NOTIFY_BOUND_DRIVER:
>> > + {
>> > + struct exynos_iommu_client *client = dev->archdata.iommu;
>> > + if (dev->archdata.iommu &&
>> > + (!pm_runtime_enabled(dev) ||
>> > + IS_ERR(dev_to_genpd(dev)))) {
>> > + int i;
>> > + for (i = 0; i < client->num_sysmmu; i++) {
>> > + struct sysmmu_drvdata *data;
>> > + pm_runtime_disable(client->sysmmu[i]);
>> > + data = dev_get_drvdata(client->sysmmu[i]);
>> > + if (!data)
>> > + continue;
>> > + data->runtime_active =
>> > + !pm_runtime_enabled(data->sysmmu);
>> > + if (data->runtime_active &&
>> > + is_sysmmu_active(data))
>> > + __sysmmu_enable_nocount(data);
>> > + }
>> > + }
>> > + break;
>> > + }
>> > + case BUS_NOTIFY_UNBOUND_DRIVER:
>> > + {
>> > + if (dev->archdata.iommu) {
>> > + __pm_genpd_remove_callbacks(dev, false);
>> > +
>> > + devm_kfree(dev, dev->archdata.iommu);
>> > +
>> > + dev->archdata.iommu = NULL;
>> > + }
>> > + break;
>> > + }
>> > + } /* switch (val) */
>> > +
>> > + return 0;
>> > +}
>> > +
>> > +static struct notifier_block sysmmu_notifier = {
>> > + .notifier_call = &sysmmu_hook_driver_register,
>> > +};
>> > +
>> > +static int __init exynos_iommu_prepare(void)
>> > +{
>> > + return bus_register_notifier(&platform_bus_type, &sysmmu_notifier);
>> > +}
>> > +arch_initcall(exynos_iommu_prepare);
>> > --
>> > 1.7.2.5
>> >
>> >
>> > _______________________________________________
>> > iommu mailing list
>> > [email protected]
>> > https://lists.linuxfoundation.org/mailman/listinfo/iommu
>

Subject: Re: [PATCH v8 10/12] iommu/exynos: add bus notifier for registering System MMU


Hi,

On Friday, July 26, 2013 08:30:17 PM Cho KyongHo wrote:
> When a device driver is registered, all constructs to handle System MMU
> is prepared by bus notifier call.

Patch description could be improved greatly by documenting what the patch
is doing and it does a lot more than simply adding bus notifier.

The patch can be also split further (at least code adding support for
muplitple System MMUs per struct exynos_iommu_client instance could be
separate which would make review a lot easier as the code wouldn't be
moved around so much).

Could you also tell me how (on which SoC/board and with what drivers) are
you testing these changes? I've tried to test v7 with FIMC and MFC devices
(on EXYNOS4210 based Universal C210 board) but as soon as I added actual
IOMMU mappings (none of your patches in this series does it BTW) I've
encountered problems (namely lockup related to clocks usage, probably
related to "master" clock, I haven't had time to debug it further yet).

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

> Signed-off-by: Cho KyongHo <[email protected]>
> ---
> drivers/iommu/exynos-iommu.c | 708 ++++++++++++++++++++++++++++++++---------
> 1 files changed, 552 insertions(+), 156 deletions(-)
>
> diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
> index f9853fe..c62c244 100644
> --- a/drivers/iommu/exynos-iommu.c
> +++ b/drivers/iommu/exynos-iommu.c
> @@ -27,6 +27,9 @@
> #include <linux/memblock.h>
> #include <linux/export.h>
> #include <linux/of.h>
> +#include <linux/of_platform.h>
> +#include <linux/pm_domain.h>
> +#include <linux/notifier.h>
>
> #include <asm/cacheflush.h>
> #include <asm/pgtable.h>
> @@ -80,7 +83,13 @@
> #define CTRL_BLOCK 0x7
> #define CTRL_DISABLE 0x0
>
> +#define CFG_LRU 0x1
> +#define CFG_QOS(n) ((n & 0xF) << 7)
> +#define CFG_MASK 0x0150FFFF /* Selecting bit 0-15, 20, 22 and 24 */
> +#define CFG_ACGEN (1 << 24) /* System MMU 3.3 only */
> +#define CFG_SYSSEL (1 << 22) /* System MMU 3.2 only */
> #define CFG_FLPDCACHE (1 << 20) /* System MMU 3.2+ only */
> +#define CFG_SHAREABLE (1 << 12) /* System MMU 3.x only */
>
> #define REG_MMU_CTRL 0x000
> #define REG_MMU_CFG 0x004
> @@ -154,6 +163,14 @@ static char *sysmmu_fault_name[SYSMMU_FAULTS_NUM] = {
> "UNKNOWN FAULT"
> };
>
> +struct exynos_iommu_client {
> + struct list_head node; /* entry of exynos_iommu_domain.clients */
> + struct device *dev;
> + spinlock_t lock;
> + int num_sysmmu;
> + struct device *sysmmu[0];
> +};
> +
> struct exynos_iommu_domain {
> struct list_head clients; /* list of sysmmu_drvdata.node */
> unsigned long *pgtable; /* lv1 page table, 16KB */
> @@ -165,12 +182,14 @@ struct exynos_iommu_domain {
> struct sysmmu_drvdata {
> struct list_head node; /* entry of exynos_iommu_domain.clients */
> struct device *sysmmu; /* System MMU's device descriptor */
> - struct device *dev; /* Owner of system MMU */
> + struct device *master; /* Owner of system MMU */
> int nsfrs;
> struct clk *clk;
> + struct clk *clk_master;
> int activations;
> rwlock_t lock;
> struct iommu_domain *domain;
> + bool runtime_active;
> unsigned long pgtable;
> void __iomem *sfrbases[0];
> };
> @@ -245,7 +264,6 @@ static void __sysmmu_tlb_invalidate_entry(void __iomem *sfrbase,
> static void __sysmmu_set_ptbase(void __iomem *sfrbase,
> unsigned long pgd)
> {
> - __raw_writel(0x1, sfrbase + REG_MMU_CFG); /* 16KB LV1, LRU */
> __raw_writel(pgd, sfrbase + REG_PT_BASE_ADDR);
>
> __sysmmu_tlb_invalidate(sfrbase);
> @@ -273,6 +291,7 @@ void exynos_sysmmu_set_prefbuf(struct device *dev,
> if (!is_sysmmu_active(data))
> goto finish;
>
> + clk_enable(data->clk_master);
> for (i = 0; i < data->nsfrs; i++) {
> if ((readl(data->sfrbases[i] + REG_MMU_VERSION) >> 28) == 3) {
> if (!sysmmu_block(data->sfrbases[i]))
> @@ -298,6 +317,7 @@ void exynos_sysmmu_set_prefbuf(struct device *dev,
> sysmmu_unblock(data->sfrbases[i]);
> }
> }
> + clk_disable(data->clk_master);
> finish:
> read_unlock_irqrestore(&data->lock, flags);
> }
> @@ -331,12 +351,13 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
> {
> /* SYSMMU is in blocked when interrupt occurred. */
> struct sysmmu_drvdata *data = dev_id;
> + struct exynos_iommu_client *client = NULL;
> enum exynos_sysmmu_inttype itype;
> unsigned long addr = -1;
> -
> int i, ret = -ENOSYS;
>
> - read_lock(&data->lock);
> + if (data->master)
> + client = data->master->archdata.iommu;
>
> WARN_ON(!is_sysmmu_active(data));
>
> @@ -348,6 +369,10 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
> break;
> }
>
> + if (client)
> + spin_lock(&client->lock);
> + read_lock(&data->lock);
> +
> if (i == data->nsfrs) {
> itype = SYSMMU_FAULT_UNKNOWN;
> } else {
> @@ -361,7 +386,7 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
> }
>
> if (data->domain)
> - ret = report_iommu_fault(data->domain, data->dev,
> + ret = report_iommu_fault(data->domain, data->master,
> addr, itype);
>
> if (!ret && (itype != SYSMMU_FAULT_UNKNOWN))
> @@ -378,177 +403,251 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
> sysmmu_unblock(data->sfrbases[i]);
>
> read_unlock(&data->lock);
> + if (client)
> + spin_unlock(&client->lock);
>
> return IRQ_HANDLED;
> }
>
> -static bool __exynos_sysmmu_disable(struct sysmmu_drvdata *data)
> +static void __sysmmu_disable_nocount(struct sysmmu_drvdata *data)
> {
> - unsigned long flags;
> - bool disabled = false;
> int i;
>
> - write_lock_irqsave(&data->lock, flags);
> + clk_enable(data->clk_master);
> + for (i = 0; i < data->nsfrs; i++) {
> + __raw_writel(CTRL_DISABLE,
> + data->sfrbases[i] + REG_MMU_CTRL);
> + __raw_writel(0, data->sfrbases[i] + REG_MMU_CFG);
> + }
>
> - if (!set_sysmmu_inactive(data))
> - goto finish;
> + clk_disable(data->clk);
> + clk_disable(data->clk_master);
> +}
>
> - for (i = 0; i < data->nsfrs; i++)
> - __raw_writel(CTRL_DISABLE, data->sfrbases[i] + REG_MMU_CTRL);
> +static bool __sysmmu_disable(struct sysmmu_drvdata *data)
> +{
> + bool disabled;
> + unsigned long flags;
>
> - if (data->clk)
> - clk_disable(data->clk);
> + write_lock_irqsave(&data->lock, flags);
>
> - disabled = true;
> - data->pgtable = 0;
> - data->domain = NULL;
> -finish:
> - write_unlock_irqrestore(&data->lock, flags);
> + disabled = set_sysmmu_inactive(data);
> +
> + if (disabled) {
> + data->pgtable = 0;
> + data->domain = NULL;
> +
> + if (data->runtime_active)
> + __sysmmu_disable_nocount(data);
>
> - if (disabled)
> dev_dbg(data->sysmmu, "Disabled\n");
> - else
> - dev_dbg(data->sysmmu, "%d times left to be disabled\n",
> + } else {
> + dev_dbg(data->sysmmu, "%d times left to disable\n",
> data->activations);
> + }
> +
> + write_unlock_irqrestore(&data->lock, flags);
>
> return disabled;
> }
>
> -/* __exynos_sysmmu_enable: Enables System MMU
> - *
> - * returns -error if an error occurred and System MMU is not enabled,
> - * 0 if the System MMU has been just enabled and 1 if System MMU was already
> - * enabled before.
> - */
> -static int __exynos_sysmmu_enable(struct sysmmu_drvdata *data,
> +
> +static void __sysmmu_init_config(struct sysmmu_drvdata *data, int idx)
> +{
> + unsigned long cfg = CFG_LRU | CFG_QOS(15);
> + int maj, min = 0;
> +
> + maj = __sysmmu_version(data, idx, &min);
> + if (maj == 3) {
> + if (min > 1) {
> + cfg |= CFG_FLPDCACHE;
> + cfg |= (min == 2) ? CFG_SYSSEL : CFG_ACGEN;
> + }
> + }
> +
> + __raw_writel(cfg, data->sfrbases[idx] + REG_MMU_CFG);
> +}
> +
> +static void __sysmmu_enable_nocount(struct sysmmu_drvdata *data)
> +{
> + int i;
> +
> + clk_enable(data->clk_master);
> + clk_enable(data->clk);
> +
> + for (i = 0; i < data->nsfrs; i++) {
> + __raw_writel(CTRL_BLOCK, data->sfrbases[i] + REG_MMU_CTRL);
> +
> + __sysmmu_init_config(data, i);
> +
> + __sysmmu_set_ptbase(data->sfrbases[i], data->pgtable);
> +
> + __raw_writel(CTRL_ENABLE, data->sfrbases[i] + REG_MMU_CTRL);
> + }
> + clk_disable(data->clk_master);
> +}
> +
> +static int __sysmmu_enable(struct sysmmu_drvdata *data,
> unsigned long pgtable, struct iommu_domain *domain)
> {
> - int i, ret = 0;
> + int ret = 0;
> unsigned long flags;
>
> write_lock_irqsave(&data->lock, flags);
> + if (set_sysmmu_active(data)) {
> + data->pgtable = pgtable;
> + data->domain = domain;
>
> - if (!set_sysmmu_active(data)) {
> - if (WARN_ON(pgtable != data->pgtable)) {
> - ret = -EBUSY;
> - set_sysmmu_inactive(data);
> - } else {
> - ret = 1;
> - }
> + if (data->runtime_active)
> + __sysmmu_enable_nocount(data);
>
> - dev_dbg(data->sysmmu, "Already enabled\n");
> - goto finish;
> + dev_dbg(data->sysmmu, "Enabled\n");
> + } else {
> + ret = (pgtable == data->pgtable) ? 1 : -EBUSY;
> +
> + dev_dbg(data->sysmmu, "already enabled\n");
> }
>
> - if (data->clk)
> - clk_enable(data->clk);
> + if (WARN_ON(ret < 0))
> + set_sysmmu_inactive(data); /* decrement count */
>
> - data->pgtable = pgtable;
> + write_unlock_irqrestore(&data->lock, flags);
>
> - for (i = 0; i < data->nsfrs; i++) {
> - unsigned int min;
> + return ret;
> +}
>
> - __sysmmu_set_ptbase(data->sfrbases[i], pgtable);
> +/* __exynos_sysmmu_enable: Enables System MMU
> + *
> + * returns -error if an error occurred and System MMU is not enabled,
> + * 0 if the System MMU has been just enabled and 1 if System MMU was already
> + * enabled before.
> + */
> +static int __exynos_sysmmu_enable(struct device *dev, unsigned long pgtable,
> + struct iommu_domain *domain)
> +{
> + int ret = 0;
> + unsigned long flags;
> + struct exynos_iommu_client *client = dev->archdata.iommu;
> + int i;
>
> - if ((__sysmmu_version(data, i, &min) == 3) && (min > 1)) {
> - unsigned long cfg;
> - cfg = __raw_readl(data->sfrbases[i] + REG_MMU_CFG);
> - __raw_writel(cfg | CFG_FLPDCACHE,
> - data->sfrbases[i] + REG_MMU_CFG);
> - }
> + if (WARN_ON(!client))
> + return -ENODEV;
>
> - __raw_writel(CTRL_ENABLE, data->sfrbases[i] + REG_MMU_CTRL);
> - }
> + spin_lock_irqsave(&client->lock, flags);
>
> - data->domain = domain;
> + for (i = 0; i < client->num_sysmmu; i++) {
> + struct sysmmu_drvdata *data =
> + dev_get_drvdata(client->sysmmu[i]);
> + ret = __sysmmu_enable(data, pgtable, domain);
> + if (ret < 0) {
> + int j;
> + for (j = 0; j < i; j++)
> + __sysmmu_disable(data);
> + break;
> + } else {
> + data->master = dev;
> + }
> + }
>
> - dev_dbg(data->sysmmu, "Enabled\n");
> -finish:
> - write_unlock_irqrestore(&data->lock, flags);
> + spin_unlock_irqrestore(&client->lock, flags);
>
> return ret;
> }
>
> int exynos_sysmmu_enable(struct device *dev, unsigned long pgtable)
> {
> - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
> int ret;
>
> BUG_ON(!memblock_is_memory(pgtable));
>
> - ret = pm_runtime_get_sync(data->sysmmu);
> - if (ret < 0) {
> - dev_dbg(data->sysmmu, "Failed to enable\n");
> - return ret;
> - }
> -
> - ret = __exynos_sysmmu_enable(data, pgtable, NULL);
> - if (WARN_ON(ret < 0)) {
> - pm_runtime_put(data->sysmmu);
> - dev_err(data->sysmmu,
> - "Already enabled with page table %#lx\n",
> - data->pgtable);
> - } else {
> - data->dev = dev;
> - }
> + ret = __exynos_sysmmu_enable(dev, pgtable, NULL);
>
> return ret;
> }
>
> static bool exynos_sysmmu_disable(struct device *dev)
> {
> - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
> - bool disabled;
> + unsigned long flags;
> + bool disabled = true;
> + struct exynos_iommu_client *client = dev->archdata.iommu;
> + int i;
>
> - disabled = __exynos_sysmmu_disable(data);
> - pm_runtime_put(data->sysmmu);
> + if (WARN_ON(!client))
> + return true;
> +
> + spin_lock_irqsave(&client->lock, flags);
> +
> + /* Every call to __sysmmu_disable() must return same result */
> + for (i = 0; i < client->num_sysmmu; i++) {
> + struct sysmmu_drvdata *data =
> + dev_get_drvdata(client->sysmmu[i]);
> + disabled = __sysmmu_disable(data);
> + if (disabled)
> + data->master = NULL;
> + }
> +
> + spin_unlock_irqrestore(&client->lock, flags);
>
> return disabled;
> }
>
> static void sysmmu_tlb_invalidate_entry(struct device *dev, unsigned long iova)
> {
> - unsigned long flags;
> - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
> + struct exynos_iommu_client *client = dev->archdata.iommu;
> + int i;
>
> - read_lock_irqsave(&data->lock, flags);
> + for (i = 0; i < client->num_sysmmu; i++) {
> + unsigned long flags;
> + struct sysmmu_drvdata *data;
>
> - if (is_sysmmu_active(data)) {
> - int i;
> - for (i = 0; i < data->nsfrs; i++) {
> - if (sysmmu_block(data->sfrbases[i])) {
> + data = dev_get_drvdata(client->sysmmu[i]);
> +
> + read_lock_irqsave(&data->lock, flags);
> + if (is_sysmmu_active(data) && data->runtime_active) {
> + int i;
> + clk_enable(data->clk_master);
> + for (i = 0; i < data->nsfrs; i++)
> __sysmmu_tlb_invalidate_entry(
> data->sfrbases[i], iova);
> - sysmmu_unblock(data->sfrbases[i]);
> - }
> + clk_disable(data->clk_master);
> + } else {
> + dev_dbg(dev,
> + "disabled. Skipping TLB invalidation @ %#lx\n",
> + iova);
> }
> - } else {
> - dev_dbg(data->sysmmu, "Disabled. Skipping invalidating TLB.\n");
> + read_unlock_irqrestore(&data->lock, flags);
> }
> -
> - read_unlock_irqrestore(&data->lock, flags);
> }
>
> void exynos_sysmmu_tlb_invalidate(struct device *dev)
> {
> - unsigned long flags;
> - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
> -
> - read_lock_irqsave(&data->lock, flags);
> + struct exynos_iommu_client *client = dev->archdata.iommu;
> + int i;
>
> - if (is_sysmmu_active(data)) {
> - int i;
> - for (i = 0; i < data->nsfrs; i++) {
> - if (sysmmu_block(data->sfrbases[i])) {
> - __sysmmu_tlb_invalidate(data->sfrbases[i]);
> - sysmmu_unblock(data->sfrbases[i]);
> + for (i = 0; i < client->num_sysmmu; i++) {
> + unsigned long flags;
> + struct sysmmu_drvdata *data;
> +
> + data = dev_get_drvdata(client->sysmmu[i]);
> +
> + read_lock_irqsave(&data->lock, flags);
> + if (is_sysmmu_active(data) &&
> + data->runtime_active) {
> + int i;
> + for (i = 0; i < data->nsfrs; i++) {
> + clk_enable(data->clk_master);
> + if (sysmmu_block(data->sfrbases[i])) {
> + __sysmmu_tlb_invalidate(
> + data->sfrbases[i]);
> + sysmmu_unblock(data->sfrbases[i]);
> + }
> + clk_disable(data->clk_master);
> }
> + } else {
> + dev_dbg(dev, "disabled. Skipping TLB invalidation\n");
> }
> - } else {
> - dev_dbg(data->sysmmu, "Disabled. Skipping invalidating TLB.\n");
> + read_unlock_irqrestore(&data->lock, flags);
> }
> -
> - read_unlock_irqrestore(&data->lock, flags);
> }
>
> static int __init exynos_sysmmu_probe(struct platform_device *pdev)
> @@ -610,12 +709,32 @@ static int __init exynos_sysmmu_probe(struct platform_device *pdev)
> pm_runtime_enable(dev);
>
> data->sysmmu = dev;
> +
> data->clk = devm_clk_get(dev, "sysmmu");
> if (IS_ERR(data->clk)) {
> dev_info(dev, "No gate clock found!\n");
> data->clk = NULL;
> }
>
> + ret = clk_prepare(data->clk);
> + if (ret) {
> + dev_err(dev, "Failed to prepare clk\n");
> + return ret;
> + }
> +
> + data->clk_master = devm_clk_get(dev, "master");
> + if (IS_ERR(data->clk_master))
> + data->clk_master = NULL;
> +
> + ret = clk_prepare(data->clk_master);
> + if (ret) {
> + clk_unprepare(data->clk);
> + dev_err(dev, "Failed to prepare master's clk\n");
> + return ret;
> + }
> +
> + data->runtime_active = !pm_runtime_enabled(dev);
> +
> rwlock_init(&data->lock);
> INIT_LIST_HEAD(&data->node);
>
> @@ -625,6 +744,34 @@ static int __init exynos_sysmmu_probe(struct platform_device *pdev)
> return ret;
> }
>
> +#ifdef CONFIG_PM_SLEEP
> +static int sysmmu_suspend(struct device *dev)
> +{
> + struct sysmmu_drvdata *data = dev_get_drvdata(dev);
> + unsigned long flags;
> + read_lock_irqsave(&data->lock, flags);
> + if (is_sysmmu_active(data) &&
> + (!pm_runtime_enabled(dev) || data->runtime_active))
> + __sysmmu_disable_nocount(data);
> + read_unlock_irqrestore(&data->lock, flags);
> + return 0;
> +}
> +
> +static int sysmmu_resume(struct device *dev)
> +{
> + struct sysmmu_drvdata *data = dev_get_drvdata(dev);
> + unsigned long flags;
> + read_lock_irqsave(&data->lock, flags);
> + if (is_sysmmu_active(data) &&
> + (!pm_runtime_enabled(dev) || data->runtime_active))
> + __sysmmu_enable_nocount(data);
> + read_unlock_irqrestore(&data->lock, flags);
> + return 0;
> +}
> +#endif
> +
> +static SIMPLE_DEV_PM_OPS(sysmmu_pm_ops, sysmmu_suspend, sysmmu_resume);
> +
> #ifdef CONFIG_OF
> static struct of_device_id sysmmu_of_match[] __initconst = {
> { .compatible = "samsung,exynos4210-sysmmu", },
> @@ -637,6 +784,7 @@ static struct platform_driver exynos_sysmmu_driver __refdata = {
> .driver = {
> .owner = THIS_MODULE,
> .name = "exynos-sysmmu",
> + .pm = &sysmmu_pm_ops,
> .of_match_table = of_match_ptr(sysmmu_of_match),
> }
> };
> @@ -689,7 +837,7 @@ err_pgtable:
> static void exynos_iommu_domain_destroy(struct iommu_domain *domain)
> {
> struct exynos_iommu_domain *priv = domain->priv;
> - struct sysmmu_drvdata *data;
> + struct exynos_iommu_client *client;
> unsigned long flags;
> int i;
>
> @@ -697,11 +845,14 @@ static void exynos_iommu_domain_destroy(struct iommu_domain *domain)
>
> spin_lock_irqsave(&priv->lock, flags);
>
> - list_for_each_entry(data, &priv->clients, node) {
> - while (!exynos_sysmmu_disable(data->dev))
> + list_for_each_entry(client, &priv->clients, node) {
> + while (!exynos_sysmmu_disable(client->dev))
> ; /* until System MMU is actually disabled */
> }
>
> + while (!list_empty(&priv->clients))
> + list_del_init(priv->clients.next);
> +
> spin_unlock_irqrestore(&priv->lock, flags);
>
> for (i = 0; i < NUM_LV1ENTRIES; i++)
> @@ -718,41 +869,26 @@ static void exynos_iommu_domain_destroy(struct iommu_domain *domain)
> static int exynos_iommu_attach_device(struct iommu_domain *domain,
> struct device *dev)
> {
> - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
> + struct exynos_iommu_client *client = dev->archdata.iommu;
> struct exynos_iommu_domain *priv = domain->priv;
> unsigned long flags;
> int ret;
>
> - ret = pm_runtime_get_sync(data->sysmmu);
> - if (ret < 0)
> - return ret;
> -
> - ret = 0;
> -
> spin_lock_irqsave(&priv->lock, flags);
>
> - ret = __exynos_sysmmu_enable(data, __pa(priv->pgtable), domain);
> -
> - if (ret == 0) {
> - /* 'data->node' must not be appeared in priv->clients */
> - BUG_ON(!list_empty(&data->node));
> - data->dev = dev;
> - list_add_tail(&data->node, &priv->clients);
> - }
> + ret = __exynos_sysmmu_enable(dev, __pa(priv->pgtable), domain);
> + if (ret == 0)
> + list_add_tail(&client->node, &priv->clients);
>
> spin_unlock_irqrestore(&priv->lock, flags);
>
> - if (ret < 0) {
> + if (ret < 0)
> dev_err(dev, "%s: Failed to attach IOMMU with pgtable %#lx\n",
> __func__, __pa(priv->pgtable));
> - pm_runtime_put(data->sysmmu);
> - } else if (ret > 0) {
> - dev_dbg(dev, "%s: IOMMU with pgtable 0x%lx already attached\n",
> - __func__, __pa(priv->pgtable));
> - } else {
> - dev_dbg(dev, "%s: Attached new IOMMU with pgtable 0x%lx\n",
> - __func__, __pa(priv->pgtable));
> - }
> + else
> + dev_dbg(dev, "%s: Attached IOMMU with pgtable 0x%lx%s\n",
> + __func__, __pa(priv->pgtable),
> + (ret == 0) ? "" : ", again");
>
> return ret;
> }
> @@ -760,39 +896,27 @@ static int exynos_iommu_attach_device(struct iommu_domain *domain,
> static void exynos_iommu_detach_device(struct iommu_domain *domain,
> struct device *dev)
> {
> - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
> + struct exynos_iommu_client *client = NULL;
> struct exynos_iommu_domain *priv = domain->priv;
> - struct list_head *pos;
> unsigned long flags;
> - bool found = false;
>
> spin_lock_irqsave(&priv->lock, flags);
>
> - list_for_each(pos, &priv->clients) {
> - if (list_entry(pos, struct sysmmu_drvdata, node) == data) {
> - found = true;
> + list_for_each_entry(client, &priv->clients, node) {
> + if (client == dev->archdata.iommu) {
> + if (exynos_sysmmu_disable(dev))
> + list_del_init(&client->node);
> break;
> }
> }
>
> - if (!found)
> - goto finish;
> + spin_unlock_irqrestore(&priv->lock, flags);
>
> - if (__exynos_sysmmu_disable(data)) {
> + if (client == dev->archdata.iommu)
> dev_dbg(dev, "%s: Detached IOMMU with pgtable %#lx\n",
> __func__, __pa(priv->pgtable));
> - list_del_init(&data->node);
> -
> - } else {
> - dev_dbg(dev, "%s: Detaching IOMMU with pgtable %#lx delayed",
> - __func__, __pa(priv->pgtable));
> - }
> -
> -finish:
> - spin_unlock_irqrestore(&priv->lock, flags);
> -
> - if (found)
> - pm_runtime_put(data->sysmmu);
> + else
> + dev_dbg(dev, "%s: No IOMMU is attached\n", __func__);
> }
>
> static unsigned long *alloc_lv2entry(unsigned long *sent, unsigned long iova,
> @@ -914,7 +1038,7 @@ static size_t exynos_iommu_unmap(struct iommu_domain *domain,
> unsigned long iova, size_t size)
> {
> struct exynos_iommu_domain *priv = domain->priv;
> - struct sysmmu_drvdata *data;
> + struct exynos_iommu_client *client;
> unsigned long flags;
> unsigned long *ent;
> size_t err_pgsize;
> @@ -975,8 +1099,8 @@ done:
> spin_unlock_irqrestore(&priv->pgtablelock, flags);
>
> spin_lock_irqsave(&priv->lock, flags);
> - list_for_each_entry(data, &priv->clients, node)
> - sysmmu_tlb_invalidate_entry(data->dev, iova);
> + list_for_each_entry(client, &priv->clients, node)
> + sysmmu_tlb_invalidate_entry(client->dev, iova);
> spin_unlock_irqrestore(&priv->lock, flags);
>
> return size;
> @@ -1055,3 +1179,275 @@ static int __init exynos_iommu_init(void)
> return ret;
> }
> subsys_initcall(exynos_iommu_init);
> +
> +#ifdef CONFIG_PM_SLEEP
> +static int sysmmu_pm_genpd_suspend(struct device *dev)
> +{
> + struct exynos_iommu_client *client = dev->archdata.iommu;
> + int ret = 0;
> + int i;
> +
> + for (i = 0; i < client->num_sysmmu; i++) {
> + ret = pm_generic_suspend(client->sysmmu[i]);
> + if (ret)
> + break;
> + }
> +
> + if (!ret)
> + ret = pm_generic_suspend(dev);
> +
> + if (ret) {
> + int j;
> +
> + for (j = 0; j < i; j++)
> + pm_generic_resume(client->sysmmu[j]);
> + }
> +
> + return ret;
> +}
> +
> +static int sysmmu_pm_genpd_resume(struct device *dev)
> +{
> + struct exynos_iommu_client *client = dev->archdata.iommu;
> + int ret = 0;
> + int i;
> +
> + for (i = 0; i < client->num_sysmmu; i++) {
> + ret = pm_generic_resume(client->sysmmu[i]);
> + if (ret)
> + break;
> + }
> +
> + if (!ret)
> + ret = pm_generic_resume(dev);
> +
> + if (ret) {
> + int j;
> +
> + for (j = 0; j < i; j++)
> + pm_generic_suspend(client->sysmmu[j]);
> + }
> +
> + return ret;
> +}
> +#endif
> +
> +#ifdef CONFIG_PM_RUNTIME
> +static void sysmmu_restore_state(struct device *sysmmu)
> +{
> + struct sysmmu_drvdata *data = dev_get_drvdata(sysmmu);
> + unsigned long flags;
> +
> + spin_lock_irqsave(&data->lock, flags);
> + data->runtime_active = true;
> + if (is_sysmmu_active(data))
> + __sysmmu_enable_nocount(data);
> + spin_unlock_irqrestore(&data->lock, flags);
> +}
> +
> +static void sysmmu_save_state(struct device *sysmmu)
> +{
> + struct sysmmu_drvdata *data = dev_get_drvdata(sysmmu);
> + unsigned long flags;
> +
> + spin_lock_irqsave(&data->lock, flags);
> + if (is_sysmmu_active(data))
> + __sysmmu_disable_nocount(data);
> + data->runtime_active = false;
> + spin_unlock_irqrestore(&data->lock, flags);
> +}
> +
> +static int sysmmu_pm_genpd_save_state(struct device *dev)
> +{
> + struct exynos_iommu_client *client = dev->archdata.iommu;
> + int (*cb)(struct device *__dev);
> + int i;
> +
> + if (dev->type && dev->type->pm)
> + cb = dev->type->pm->runtime_suspend;
> + else if (dev->class && dev->class->pm)
> + cb = dev->class->pm->runtime_suspend;
> + else if (dev->bus && dev->bus->pm)
> + cb = dev->bus->pm->runtime_suspend;
> + else
> + cb = NULL;
> +
> + if (!cb && dev->driver && dev->driver->pm)
> + cb = dev->driver->pm->runtime_suspend;
> +
> + if (cb) {
> + int ret;
> +
> + ret = cb(dev);
> + if (ret)
> + return ret;
> + }
> +
> + for (i = 0; i < client->num_sysmmu; i++)
> + sysmmu_save_state(client->sysmmu[i]);
> +
> + return 0;
> +}
> +
> +static int sysmmu_pm_genpd_restore_state(struct device *dev)
> +{
> + struct exynos_iommu_client *client = dev->archdata.iommu;
> + int (*cb)(struct device *__dev);
> + int i;
> +
> + if (dev->type && dev->type->pm)
> + cb = dev->type->pm->runtime_resume;
> + else if (dev->class && dev->class->pm)
> + cb = dev->class->pm->runtime_resume;
> + else if (dev->bus && dev->bus->pm)
> + cb = dev->bus->pm->runtime_resume;
> + else
> + cb = NULL;
> +
> + if (!cb && dev->driver && dev->driver->pm)
> + cb = dev->driver->pm->runtime_resume;
> +
> + for (i = 0; i < client->num_sysmmu; i++)
> + sysmmu_restore_state(client->sysmmu[i]);
> +
> + if (cb) {
> + int ret;
> + ret = cb(dev);
> + if (ret) {
> + for (i = 0; i < client->num_sysmmu; i++)
> + sysmmu_save_state(client->sysmmu[i]);
> + return ret;
> + }
> + }
> +
> + return 0;
> +}
> +#endif
> +
> +#ifdef CONFIG_PM_GENERIC_DOMAINS
> +struct gpd_dev_ops sysmmu_devpm_ops = {
> +#ifdef CONFIG_PM_RUNTIME
> + .save_state = &sysmmu_pm_genpd_save_state,
> + .restore_state = &sysmmu_pm_genpd_restore_state,
> +#endif
> +#ifdef CONFIG_PM_SLEEP
> + .suspend = &sysmmu_pm_genpd_suspend,
> + .resume = &sysmmu_pm_genpd_resume,
> +#endif
> +};
> +#endif /* CONFIG_PM_GENERIC_DOMAINS */
> +
> +static int sysmmu_hook_driver_register(struct notifier_block *nb,
> + unsigned long val,
> + void *p)
> +{
> + struct device *dev = p;
> +
> + switch (val) {
> + case BUS_NOTIFY_BIND_DRIVER:
> + {
> + int i = 0;
> + int size = 0;
> + const __be32 *phandle;
> + struct exynos_iommu_client *client;
> +
> + phandle = of_get_property(dev->of_node, "iommu", &size);
> + if (!phandle)
> + break;
> +
> + size = size / sizeof(*phandle); /* number of elements */
> +
> + client = devm_kzalloc(dev, sizeof(*client) * size, GFP_KERNEL);
> + if (!client) {
> + dev_err(dev, "No Memory for exynos_iommu_client\n");
> + return -ENOMEM;
> + }
> +
> + client->num_sysmmu = size;
> + client->dev = dev;
> + INIT_LIST_HEAD(&client->node);
> + spin_lock_init(&client->lock);
> +
> + for (i = 0; i < size; i++) {
> + struct device_node *np;
> + struct platform_device *sysmmu;
> +
> + /* this always success: see above of_find_property() */
> + np = of_parse_phandle(dev->of_node, "iommu", i);
> +
> + sysmmu = of_find_device_by_node(np);
> + if (!sysmmu) {
> + dev_err(dev,
> + "sysmmu node '%s' is not found\n",
> + np->name);
> + break;
> + }
> +
> + client->sysmmu[i] = &sysmmu->dev;
> + }
> +
> + if (i < size) {
> + while (--i >= 0)
> + of_node_put(client->sysmmu[i]->of_node);
> + devm_kfree(dev, client);
> + return -ENODEV;
> + }
> +
> + i = pm_genpd_add_callbacks(dev, &sysmmu_devpm_ops, NULL);
> + if (i && (i != -ENOSYS)) {
> + dev_err(dev,
> + "Failed to register 'dev_pm_ops' for iommu\n");
> + devm_kfree(dev, client);
> + return i;
> + }
> +
> + dev->archdata.iommu = client;
> + break;
> + }
> + case BUS_NOTIFY_BOUND_DRIVER:
> + {
> + struct exynos_iommu_client *client = dev->archdata.iommu;
> + if (dev->archdata.iommu &&
> + (!pm_runtime_enabled(dev) ||
> + IS_ERR(dev_to_genpd(dev)))) {
> + int i;
> + for (i = 0; i < client->num_sysmmu; i++) {
> + struct sysmmu_drvdata *data;
> + pm_runtime_disable(client->sysmmu[i]);
> + data = dev_get_drvdata(client->sysmmu[i]);
> + if (!data)
> + continue;
> + data->runtime_active =
> + !pm_runtime_enabled(data->sysmmu);
> + if (data->runtime_active &&
> + is_sysmmu_active(data))
> + __sysmmu_enable_nocount(data);
> + }
> + }
> + break;
> + }
> + case BUS_NOTIFY_UNBOUND_DRIVER:
> + {
> + if (dev->archdata.iommu) {
> + __pm_genpd_remove_callbacks(dev, false);
> +
> + devm_kfree(dev, dev->archdata.iommu);
> +
> + dev->archdata.iommu = NULL;
> + }
> + break;
> + }
> + } /* switch (val) */
> +
> + return 0;
> +}
> +
> +static struct notifier_block sysmmu_notifier = {
> + .notifier_call = &sysmmu_hook_driver_register,
> +};
> +
> +static int __init exynos_iommu_prepare(void)
> +{
> + return bus_register_notifier(&platform_bus_type, &sysmmu_notifier);
> +}
> +arch_initcall(exynos_iommu_prepare);

2013-08-05 13:18:05

by Cho KyongHo

[permalink] [raw]
Subject: RE: [PATCH v8 10/12] iommu/exynos: add bus notifier for registering System MMU

> -----Original Message-----
> From: Bartlomiej Zolnierkiewicz [mailto:[email protected]]
> Sent: Saturday, August 03, 2013 2:32 AM
>
> Hi,
>
> On Friday, July 26, 2013 08:30:17 PM Cho KyongHo wrote:
> > When a device driver is registered, all constructs to handle System MMU
> > is prepared by bus notifier call.
>
> Patch description could be improved greatly by documenting what the patch
> is doing and it does a lot more than simply adding bus notifier.
>
> The patch can be also split further (at least code adding support for
> muplitple System MMUs per struct exynos_iommu_client instance could be
> separate which would make review a lot easier as the code wouldn't be
> moved around so much).
>
> Could you also tell me how (on which SoC/board and with what drivers) are
> you testing these changes? I've tried to test v7 with FIMC and MFC devices
> (on EXYNOS4210 based Universal C210 board) but as soon as I added actual
> IOMMU mappings (none of your patches in this series does it BTW) I've
> encountered problems (namely lockup related to clocks usage, probably
> related to "master" clock, I haven't had time to debug it further yet).
>

I am just testing if each System MMU is correctly enabled and disabled or page
tables are consistently managed. I does not run MFC nor FIMC with System MMU.

Please let me know if you found the problem.

> Best regards,
> --
> Bartlomiej Zolnierkiewicz
> Samsung R&D Institute Poland
> Samsung Electronics
>
> > Signed-off-by: Cho KyongHo <[email protected]>
> > ---
> > drivers/iommu/exynos-iommu.c | 708 ++++++++++++++++++++++++++++++++---------
> > 1 files changed, 552 insertions(+), 156 deletions(-)
> >
> > diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
> > index f9853fe..c62c244 100644
> > --- a/drivers/iommu/exynos-iommu.c
> > +++ b/drivers/iommu/exynos-iommu.c
> > @@ -27,6 +27,9 @@
> > #include <linux/memblock.h>
> > #include <linux/export.h>
> > #include <linux/of.h>
> > +#include <linux/of_platform.h>
> > +#include <linux/pm_domain.h>
> > +#include <linux/notifier.h>
> >
> > #include <asm/cacheflush.h>
> > #include <asm/pgtable.h>
> > @@ -80,7 +83,13 @@
> > #define CTRL_BLOCK 0x7
> > #define CTRL_DISABLE 0x0
> >
> > +#define CFG_LRU 0x1
> > +#define CFG_QOS(n) ((n & 0xF) << 7)
> > +#define CFG_MASK 0x0150FFFF /* Selecting bit 0-15, 20, 22 and 24 */
> > +#define CFG_ACGEN (1 << 24) /* System MMU 3.3 only */
> > +#define CFG_SYSSEL (1 << 22) /* System MMU 3.2 only */
> > #define CFG_FLPDCACHE (1 << 20) /* System MMU 3.2+ only */
> > +#define CFG_SHAREABLE (1 << 12) /* System MMU 3.x only */
> >
> > #define REG_MMU_CTRL 0x000
> > #define REG_MMU_CFG 0x004
> > @@ -154,6 +163,14 @@ static char *sysmmu_fault_name[SYSMMU_FAULTS_NUM] = {
> > "UNKNOWN FAULT"
> > };
> >
> > +struct exynos_iommu_client {
> > + struct list_head node; /* entry of exynos_iommu_domain.clients */
> > + struct device *dev;
> > + spinlock_t lock;
> > + int num_sysmmu;
> > + struct device *sysmmu[0];
> > +};
> > +
> > struct exynos_iommu_domain {
> > struct list_head clients; /* list of sysmmu_drvdata.node */
> > unsigned long *pgtable; /* lv1 page table, 16KB */
> > @@ -165,12 +182,14 @@ struct exynos_iommu_domain {
> > struct sysmmu_drvdata {
> > struct list_head node; /* entry of exynos_iommu_domain.clients */
> > struct device *sysmmu; /* System MMU's device descriptor */
> > - struct device *dev; /* Owner of system MMU */
> > + struct device *master; /* Owner of system MMU */
> > int nsfrs;
> > struct clk *clk;
> > + struct clk *clk_master;
> > int activations;
> > rwlock_t lock;
> > struct iommu_domain *domain;
> > + bool runtime_active;
> > unsigned long pgtable;
> > void __iomem *sfrbases[0];
> > };
> > @@ -245,7 +264,6 @@ static void __sysmmu_tlb_invalidate_entry(void __iomem *sfrbase,
> > static void __sysmmu_set_ptbase(void __iomem *sfrbase,
> > unsigned long pgd)
> > {
> > - __raw_writel(0x1, sfrbase + REG_MMU_CFG); /* 16KB LV1, LRU */
> > __raw_writel(pgd, sfrbase + REG_PT_BASE_ADDR);
> >
> > __sysmmu_tlb_invalidate(sfrbase);
> > @@ -273,6 +291,7 @@ void exynos_sysmmu_set_prefbuf(struct device *dev,
> > if (!is_sysmmu_active(data))
> > goto finish;
> >
> > + clk_enable(data->clk_master);
> > for (i = 0; i < data->nsfrs; i++) {
> > if ((readl(data->sfrbases[i] + REG_MMU_VERSION) >> 28) == 3) {
> > if (!sysmmu_block(data->sfrbases[i]))
> > @@ -298,6 +317,7 @@ void exynos_sysmmu_set_prefbuf(struct device *dev,
> > sysmmu_unblock(data->sfrbases[i]);
> > }
> > }
> > + clk_disable(data->clk_master);
> > finish:
> > read_unlock_irqrestore(&data->lock, flags);
> > }
> > @@ -331,12 +351,13 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
> > {
> > /* SYSMMU is in blocked when interrupt occurred. */
> > struct sysmmu_drvdata *data = dev_id;
> > + struct exynos_iommu_client *client = NULL;
> > enum exynos_sysmmu_inttype itype;
> > unsigned long addr = -1;
> > -
> > int i, ret = -ENOSYS;
> >
> > - read_lock(&data->lock);
> > + if (data->master)
> > + client = data->master->archdata.iommu;
> >
> > WARN_ON(!is_sysmmu_active(data));
> >
> > @@ -348,6 +369,10 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
> > break;
> > }
> >
> > + if (client)
> > + spin_lock(&client->lock);
> > + read_lock(&data->lock);
> > +
> > if (i == data->nsfrs) {
> > itype = SYSMMU_FAULT_UNKNOWN;
> > } else {
> > @@ -361,7 +386,7 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
> > }
> >
> > if (data->domain)
> > - ret = report_iommu_fault(data->domain, data->dev,
> > + ret = report_iommu_fault(data->domain, data->master,
> > addr, itype);
> >
> > if (!ret && (itype != SYSMMU_FAULT_UNKNOWN))
> > @@ -378,177 +403,251 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
> > sysmmu_unblock(data->sfrbases[i]);
> >
> > read_unlock(&data->lock);
> > + if (client)
> > + spin_unlock(&client->lock);
> >
> > return IRQ_HANDLED;
> > }
> >
> > -static bool __exynos_sysmmu_disable(struct sysmmu_drvdata *data)
> > +static void __sysmmu_disable_nocount(struct sysmmu_drvdata *data)
> > {
> > - unsigned long flags;
> > - bool disabled = false;
> > int i;
> >
> > - write_lock_irqsave(&data->lock, flags);
> > + clk_enable(data->clk_master);
> > + for (i = 0; i < data->nsfrs; i++) {
> > + __raw_writel(CTRL_DISABLE,
> > + data->sfrbases[i] + REG_MMU_CTRL);
> > + __raw_writel(0, data->sfrbases[i] + REG_MMU_CFG);
> > + }
> >
> > - if (!set_sysmmu_inactive(data))
> > - goto finish;
> > + clk_disable(data->clk);
> > + clk_disable(data->clk_master);
> > +}
> >
> > - for (i = 0; i < data->nsfrs; i++)
> > - __raw_writel(CTRL_DISABLE, data->sfrbases[i] + REG_MMU_CTRL);
> > +static bool __sysmmu_disable(struct sysmmu_drvdata *data)
> > +{
> > + bool disabled;
> > + unsigned long flags;
> >
> > - if (data->clk)
> > - clk_disable(data->clk);
> > + write_lock_irqsave(&data->lock, flags);
> >
> > - disabled = true;
> > - data->pgtable = 0;
> > - data->domain = NULL;
> > -finish:
> > - write_unlock_irqrestore(&data->lock, flags);
> > + disabled = set_sysmmu_inactive(data);
> > +
> > + if (disabled) {
> > + data->pgtable = 0;
> > + data->domain = NULL;
> > +
> > + if (data->runtime_active)
> > + __sysmmu_disable_nocount(data);
> >
> > - if (disabled)
> > dev_dbg(data->sysmmu, "Disabled\n");
> > - else
> > - dev_dbg(data->sysmmu, "%d times left to be disabled\n",
> > + } else {
> > + dev_dbg(data->sysmmu, "%d times left to disable\n",
> > data->activations);
> > + }
> > +
> > + write_unlock_irqrestore(&data->lock, flags);
> >
> > return disabled;
> > }
> >
> > -/* __exynos_sysmmu_enable: Enables System MMU
> > - *
> > - * returns -error if an error occurred and System MMU is not enabled,
> > - * 0 if the System MMU has been just enabled and 1 if System MMU was already
> > - * enabled before.
> > - */
> > -static int __exynos_sysmmu_enable(struct sysmmu_drvdata *data,
> > +
> > +static void __sysmmu_init_config(struct sysmmu_drvdata *data, int idx)
> > +{
> > + unsigned long cfg = CFG_LRU | CFG_QOS(15);
> > + int maj, min = 0;
> > +
> > + maj = __sysmmu_version(data, idx, &min);
> > + if (maj == 3) {
> > + if (min > 1) {
> > + cfg |= CFG_FLPDCACHE;
> > + cfg |= (min == 2) ? CFG_SYSSEL : CFG_ACGEN;
> > + }
> > + }
> > +
> > + __raw_writel(cfg, data->sfrbases[idx] + REG_MMU_CFG);
> > +}
> > +
> > +static void __sysmmu_enable_nocount(struct sysmmu_drvdata *data)
> > +{
> > + int i;
> > +
> > + clk_enable(data->clk_master);
> > + clk_enable(data->clk);
> > +
> > + for (i = 0; i < data->nsfrs; i++) {
> > + __raw_writel(CTRL_BLOCK, data->sfrbases[i] + REG_MMU_CTRL);
> > +
> > + __sysmmu_init_config(data, i);
> > +
> > + __sysmmu_set_ptbase(data->sfrbases[i], data->pgtable);
> > +
> > + __raw_writel(CTRL_ENABLE, data->sfrbases[i] + REG_MMU_CTRL);
> > + }
> > + clk_disable(data->clk_master);
> > +}
> > +
> > +static int __sysmmu_enable(struct sysmmu_drvdata *data,
> > unsigned long pgtable, struct iommu_domain *domain)
> > {
> > - int i, ret = 0;
> > + int ret = 0;
> > unsigned long flags;
> >
> > write_lock_irqsave(&data->lock, flags);
> > + if (set_sysmmu_active(data)) {
> > + data->pgtable = pgtable;
> > + data->domain = domain;
> >
> > - if (!set_sysmmu_active(data)) {
> > - if (WARN_ON(pgtable != data->pgtable)) {
> > - ret = -EBUSY;
> > - set_sysmmu_inactive(data);
> > - } else {
> > - ret = 1;
> > - }
> > + if (data->runtime_active)
> > + __sysmmu_enable_nocount(data);
> >
> > - dev_dbg(data->sysmmu, "Already enabled\n");
> > - goto finish;
> > + dev_dbg(data->sysmmu, "Enabled\n");
> > + } else {
> > + ret = (pgtable == data->pgtable) ? 1 : -EBUSY;
> > +
> > + dev_dbg(data->sysmmu, "already enabled\n");
> > }
> >
> > - if (data->clk)
> > - clk_enable(data->clk);
> > + if (WARN_ON(ret < 0))
> > + set_sysmmu_inactive(data); /* decrement count */
> >
> > - data->pgtable = pgtable;
> > + write_unlock_irqrestore(&data->lock, flags);
> >
> > - for (i = 0; i < data->nsfrs; i++) {
> > - unsigned int min;
> > + return ret;
> > +}
> >
> > - __sysmmu_set_ptbase(data->sfrbases[i], pgtable);
> > +/* __exynos_sysmmu_enable: Enables System MMU
> > + *
> > + * returns -error if an error occurred and System MMU is not enabled,
> > + * 0 if the System MMU has been just enabled and 1 if System MMU was already
> > + * enabled before.
> > + */
> > +static int __exynos_sysmmu_enable(struct device *dev, unsigned long pgtable,
> > + struct iommu_domain *domain)
> > +{
> > + int ret = 0;
> > + unsigned long flags;
> > + struct exynos_iommu_client *client = dev->archdata.iommu;
> > + int i;
> >
> > - if ((__sysmmu_version(data, i, &min) == 3) && (min > 1)) {
> > - unsigned long cfg;
> > - cfg = __raw_readl(data->sfrbases[i] + REG_MMU_CFG);
> > - __raw_writel(cfg | CFG_FLPDCACHE,
> > - data->sfrbases[i] + REG_MMU_CFG);
> > - }
> > + if (WARN_ON(!client))
> > + return -ENODEV;
> >
> > - __raw_writel(CTRL_ENABLE, data->sfrbases[i] + REG_MMU_CTRL);
> > - }
> > + spin_lock_irqsave(&client->lock, flags);
> >
> > - data->domain = domain;
> > + for (i = 0; i < client->num_sysmmu; i++) {
> > + struct sysmmu_drvdata *data =
> > + dev_get_drvdata(client->sysmmu[i]);
> > + ret = __sysmmu_enable(data, pgtable, domain);
> > + if (ret < 0) {
> > + int j;
> > + for (j = 0; j < i; j++)
> > + __sysmmu_disable(data);
> > + break;
> > + } else {
> > + data->master = dev;
> > + }
> > + }
> >
> > - dev_dbg(data->sysmmu, "Enabled\n");
> > -finish:
> > - write_unlock_irqrestore(&data->lock, flags);
> > + spin_unlock_irqrestore(&client->lock, flags);
> >
> > return ret;
> > }
> >
> > int exynos_sysmmu_enable(struct device *dev, unsigned long pgtable)
> > {
> > - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
> > int ret;
> >
> > BUG_ON(!memblock_is_memory(pgtable));
> >
> > - ret = pm_runtime_get_sync(data->sysmmu);
> > - if (ret < 0) {
> > - dev_dbg(data->sysmmu, "Failed to enable\n");
> > - return ret;
> > - }
> > -
> > - ret = __exynos_sysmmu_enable(data, pgtable, NULL);
> > - if (WARN_ON(ret < 0)) {
> > - pm_runtime_put(data->sysmmu);
> > - dev_err(data->sysmmu,
> > - "Already enabled with page table %#lx\n",
> > - data->pgtable);
> > - } else {
> > - data->dev = dev;
> > - }
> > + ret = __exynos_sysmmu_enable(dev, pgtable, NULL);
> >
> > return ret;
> > }
> >
> > static bool exynos_sysmmu_disable(struct device *dev)
> > {
> > - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
> > - bool disabled;
> > + unsigned long flags;
> > + bool disabled = true;
> > + struct exynos_iommu_client *client = dev->archdata.iommu;
> > + int i;
> >
> > - disabled = __exynos_sysmmu_disable(data);
> > - pm_runtime_put(data->sysmmu);
> > + if (WARN_ON(!client))
> > + return true;
> > +
> > + spin_lock_irqsave(&client->lock, flags);
> > +
> > + /* Every call to __sysmmu_disable() must return same result */
> > + for (i = 0; i < client->num_sysmmu; i++) {
> > + struct sysmmu_drvdata *data =
> > + dev_get_drvdata(client->sysmmu[i]);
> > + disabled = __sysmmu_disable(data);
> > + if (disabled)
> > + data->master = NULL;
> > + }
> > +
> > + spin_unlock_irqrestore(&client->lock, flags);
> >
> > return disabled;
> > }
> >
> > static void sysmmu_tlb_invalidate_entry(struct device *dev, unsigned long iova)
> > {
> > - unsigned long flags;
> > - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
> > + struct exynos_iommu_client *client = dev->archdata.iommu;
> > + int i;
> >
> > - read_lock_irqsave(&data->lock, flags);
> > + for (i = 0; i < client->num_sysmmu; i++) {
> > + unsigned long flags;
> > + struct sysmmu_drvdata *data;
> >
> > - if (is_sysmmu_active(data)) {
> > - int i;
> > - for (i = 0; i < data->nsfrs; i++) {
> > - if (sysmmu_block(data->sfrbases[i])) {
> > + data = dev_get_drvdata(client->sysmmu[i]);
> > +
> > + read_lock_irqsave(&data->lock, flags);
> > + if (is_sysmmu_active(data) && data->runtime_active) {
> > + int i;
> > + clk_enable(data->clk_master);
> > + for (i = 0; i < data->nsfrs; i++)
> > __sysmmu_tlb_invalidate_entry(
> > data->sfrbases[i], iova);
> > - sysmmu_unblock(data->sfrbases[i]);
> > - }
> > + clk_disable(data->clk_master);
> > + } else {
> > + dev_dbg(dev,
> > + "disabled. Skipping TLB invalidation @ %#lx\n",
> > + iova);
> > }
> > - } else {
> > - dev_dbg(data->sysmmu, "Disabled. Skipping invalidating TLB.\n");
> > + read_unlock_irqrestore(&data->lock, flags);
> > }
> > -
> > - read_unlock_irqrestore(&data->lock, flags);
> > }
> >
> > void exynos_sysmmu_tlb_invalidate(struct device *dev)
> > {
> > - unsigned long flags;
> > - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
> > -
> > - read_lock_irqsave(&data->lock, flags);
> > + struct exynos_iommu_client *client = dev->archdata.iommu;
> > + int i;
> >
> > - if (is_sysmmu_active(data)) {
> > - int i;
> > - for (i = 0; i < data->nsfrs; i++) {
> > - if (sysmmu_block(data->sfrbases[i])) {
> > - __sysmmu_tlb_invalidate(data->sfrbases[i]);
> > - sysmmu_unblock(data->sfrbases[i]);
> > + for (i = 0; i < client->num_sysmmu; i++) {
> > + unsigned long flags;
> > + struct sysmmu_drvdata *data;
> > +
> > + data = dev_get_drvdata(client->sysmmu[i]);
> > +
> > + read_lock_irqsave(&data->lock, flags);
> > + if (is_sysmmu_active(data) &&
> > + data->runtime_active) {
> > + int i;
> > + for (i = 0; i < data->nsfrs; i++) {
> > + clk_enable(data->clk_master);
> > + if (sysmmu_block(data->sfrbases[i])) {
> > + __sysmmu_tlb_invalidate(
> > + data->sfrbases[i]);
> > + sysmmu_unblock(data->sfrbases[i]);
> > + }
> > + clk_disable(data->clk_master);
> > }
> > + } else {
> > + dev_dbg(dev, "disabled. Skipping TLB invalidation\n");
> > }
> > - } else {
> > - dev_dbg(data->sysmmu, "Disabled. Skipping invalidating TLB.\n");
> > + read_unlock_irqrestore(&data->lock, flags);
> > }
> > -
> > - read_unlock_irqrestore(&data->lock, flags);
> > }
> >
> > static int __init exynos_sysmmu_probe(struct platform_device *pdev)
> > @@ -610,12 +709,32 @@ static int __init exynos_sysmmu_probe(struct platform_device *pdev)
> > pm_runtime_enable(dev);
> >
> > data->sysmmu = dev;
> > +
> > data->clk = devm_clk_get(dev, "sysmmu");
> > if (IS_ERR(data->clk)) {
> > dev_info(dev, "No gate clock found!\n");
> > data->clk = NULL;
> > }
> >
> > + ret = clk_prepare(data->clk);
> > + if (ret) {
> > + dev_err(dev, "Failed to prepare clk\n");
> > + return ret;
> > + }
> > +
> > + data->clk_master = devm_clk_get(dev, "master");
> > + if (IS_ERR(data->clk_master))
> > + data->clk_master = NULL;
> > +
> > + ret = clk_prepare(data->clk_master);
> > + if (ret) {
> > + clk_unprepare(data->clk);
> > + dev_err(dev, "Failed to prepare master's clk\n");
> > + return ret;
> > + }
> > +
> > + data->runtime_active = !pm_runtime_enabled(dev);
> > +
> > rwlock_init(&data->lock);
> > INIT_LIST_HEAD(&data->node);
> >
> > @@ -625,6 +744,34 @@ static int __init exynos_sysmmu_probe(struct platform_device *pdev)
> > return ret;
> > }
> >
> > +#ifdef CONFIG_PM_SLEEP
> > +static int sysmmu_suspend(struct device *dev)
> > +{
> > + struct sysmmu_drvdata *data = dev_get_drvdata(dev);
> > + unsigned long flags;
> > + read_lock_irqsave(&data->lock, flags);
> > + if (is_sysmmu_active(data) &&
> > + (!pm_runtime_enabled(dev) || data->runtime_active))
> > + __sysmmu_disable_nocount(data);
> > + read_unlock_irqrestore(&data->lock, flags);
> > + return 0;
> > +}
> > +
> > +static int sysmmu_resume(struct device *dev)
> > +{
> > + struct sysmmu_drvdata *data = dev_get_drvdata(dev);
> > + unsigned long flags;
> > + read_lock_irqsave(&data->lock, flags);
> > + if (is_sysmmu_active(data) &&
> > + (!pm_runtime_enabled(dev) || data->runtime_active))
> > + __sysmmu_enable_nocount(data);
> > + read_unlock_irqrestore(&data->lock, flags);
> > + return 0;
> > +}
> > +#endif
> > +
> > +static SIMPLE_DEV_PM_OPS(sysmmu_pm_ops, sysmmu_suspend, sysmmu_resume);
> > +
> > #ifdef CONFIG_OF
> > static struct of_device_id sysmmu_of_match[] __initconst = {
> > { .compatible = "samsung,exynos4210-sysmmu", },
> > @@ -637,6 +784,7 @@ static struct platform_driver exynos_sysmmu_driver __refdata = {
> > .driver = {
> > .owner = THIS_MODULE,
> > .name = "exynos-sysmmu",
> > + .pm = &sysmmu_pm_ops,
> > .of_match_table = of_match_ptr(sysmmu_of_match),
> > }
> > };
> > @@ -689,7 +837,7 @@ err_pgtable:
> > static void exynos_iommu_domain_destroy(struct iommu_domain *domain)
> > {
> > struct exynos_iommu_domain *priv = domain->priv;
> > - struct sysmmu_drvdata *data;
> > + struct exynos_iommu_client *client;
> > unsigned long flags;
> > int i;
> >
> > @@ -697,11 +845,14 @@ static void exynos_iommu_domain_destroy(struct iommu_domain *domain)
> >
> > spin_lock_irqsave(&priv->lock, flags);
> >
> > - list_for_each_entry(data, &priv->clients, node) {
> > - while (!exynos_sysmmu_disable(data->dev))
> > + list_for_each_entry(client, &priv->clients, node) {
> > + while (!exynos_sysmmu_disable(client->dev))
> > ; /* until System MMU is actually disabled */
> > }
> >
> > + while (!list_empty(&priv->clients))
> > + list_del_init(priv->clients.next);
> > +
> > spin_unlock_irqrestore(&priv->lock, flags);
> >
> > for (i = 0; i < NUM_LV1ENTRIES; i++)
> > @@ -718,41 +869,26 @@ static void exynos_iommu_domain_destroy(struct iommu_domain *domain)
> > static int exynos_iommu_attach_device(struct iommu_domain *domain,
> > struct device *dev)
> > {
> > - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
> > + struct exynos_iommu_client *client = dev->archdata.iommu;
> > struct exynos_iommu_domain *priv = domain->priv;
> > unsigned long flags;
> > int ret;
> >
> > - ret = pm_runtime_get_sync(data->sysmmu);
> > - if (ret < 0)
> > - return ret;
> > -
> > - ret = 0;
> > -
> > spin_lock_irqsave(&priv->lock, flags);
> >
> > - ret = __exynos_sysmmu_enable(data, __pa(priv->pgtable), domain);
> > -
> > - if (ret == 0) {
> > - /* 'data->node' must not be appeared in priv->clients */
> > - BUG_ON(!list_empty(&data->node));
> > - data->dev = dev;
> > - list_add_tail(&data->node, &priv->clients);
> > - }
> > + ret = __exynos_sysmmu_enable(dev, __pa(priv->pgtable), domain);
> > + if (ret == 0)
> > + list_add_tail(&client->node, &priv->clients);
> >
> > spin_unlock_irqrestore(&priv->lock, flags);
> >
> > - if (ret < 0) {
> > + if (ret < 0)
> > dev_err(dev, "%s: Failed to attach IOMMU with pgtable %#lx\n",
> > __func__, __pa(priv->pgtable));
> > - pm_runtime_put(data->sysmmu);
> > - } else if (ret > 0) {
> > - dev_dbg(dev, "%s: IOMMU with pgtable 0x%lx already attached\n",
> > - __func__, __pa(priv->pgtable));
> > - } else {
> > - dev_dbg(dev, "%s: Attached new IOMMU with pgtable 0x%lx\n",
> > - __func__, __pa(priv->pgtable));
> > - }
> > + else
> > + dev_dbg(dev, "%s: Attached IOMMU with pgtable 0x%lx%s\n",
> > + __func__, __pa(priv->pgtable),
> > + (ret == 0) ? "" : ", again");
> >
> > return ret;
> > }
> > @@ -760,39 +896,27 @@ static int exynos_iommu_attach_device(struct iommu_domain *domain,
> > static void exynos_iommu_detach_device(struct iommu_domain *domain,
> > struct device *dev)
> > {
> > - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu);
> > + struct exynos_iommu_client *client = NULL;
> > struct exynos_iommu_domain *priv = domain->priv;
> > - struct list_head *pos;
> > unsigned long flags;
> > - bool found = false;
> >
> > spin_lock_irqsave(&priv->lock, flags);
> >
> > - list_for_each(pos, &priv->clients) {
> > - if (list_entry(pos, struct sysmmu_drvdata, node) == data) {
> > - found = true;
> > + list_for_each_entry(client, &priv->clients, node) {
> > + if (client == dev->archdata.iommu) {
> > + if (exynos_sysmmu_disable(dev))
> > + list_del_init(&client->node);
> > break;
> > }
> > }
> >
> > - if (!found)
> > - goto finish;
> > + spin_unlock_irqrestore(&priv->lock, flags);
> >
> > - if (__exynos_sysmmu_disable(data)) {
> > + if (client == dev->archdata.iommu)
> > dev_dbg(dev, "%s: Detached IOMMU with pgtable %#lx\n",
> > __func__, __pa(priv->pgtable));
> > - list_del_init(&data->node);
> > -
> > - } else {
> > - dev_dbg(dev, "%s: Detaching IOMMU with pgtable %#lx delayed",
> > - __func__, __pa(priv->pgtable));
> > - }
> > -
> > -finish:
> > - spin_unlock_irqrestore(&priv->lock, flags);
> > -
> > - if (found)
> > - pm_runtime_put(data->sysmmu);
> > + else
> > + dev_dbg(dev, "%s: No IOMMU is attached\n", __func__);
> > }
> >
> > static unsigned long *alloc_lv2entry(unsigned long *sent, unsigned long iova,
> > @@ -914,7 +1038,7 @@ static size_t exynos_iommu_unmap(struct iommu_domain *domain,
> > unsigned long iova, size_t size)
> > {
> > struct exynos_iommu_domain *priv = domain->priv;
> > - struct sysmmu_drvdata *data;
> > + struct exynos_iommu_client *client;
> > unsigned long flags;
> > unsigned long *ent;
> > size_t err_pgsize;
> > @@ -975,8 +1099,8 @@ done:
> > spin_unlock_irqrestore(&priv->pgtablelock, flags);
> >
> > spin_lock_irqsave(&priv->lock, flags);
> > - list_for_each_entry(data, &priv->clients, node)
> > - sysmmu_tlb_invalidate_entry(data->dev, iova);
> > + list_for_each_entry(client, &priv->clients, node)
> > + sysmmu_tlb_invalidate_entry(client->dev, iova);
> > spin_unlock_irqrestore(&priv->lock, flags);
> >
> > return size;
> > @@ -1055,3 +1179,275 @@ static int __init exynos_iommu_init(void)
> > return ret;
> > }
> > subsys_initcall(exynos_iommu_init);
> > +
> > +#ifdef CONFIG_PM_SLEEP
> > +static int sysmmu_pm_genpd_suspend(struct device *dev)
> > +{
> > + struct exynos_iommu_client *client = dev->archdata.iommu;
> > + int ret = 0;
> > + int i;
> > +
> > + for (i = 0; i < client->num_sysmmu; i++) {
> > + ret = pm_generic_suspend(client->sysmmu[i]);
> > + if (ret)
> > + break;
> > + }
> > +
> > + if (!ret)
> > + ret = pm_generic_suspend(dev);
> > +
> > + if (ret) {
> > + int j;
> > +
> > + for (j = 0; j < i; j++)
> > + pm_generic_resume(client->sysmmu[j]);
> > + }
> > +
> > + return ret;
> > +}
> > +
> > +static int sysmmu_pm_genpd_resume(struct device *dev)
> > +{
> > + struct exynos_iommu_client *client = dev->archdata.iommu;
> > + int ret = 0;
> > + int i;
> > +
> > + for (i = 0; i < client->num_sysmmu; i++) {
> > + ret = pm_generic_resume(client->sysmmu[i]);
> > + if (ret)
> > + break;
> > + }
> > +
> > + if (!ret)
> > + ret = pm_generic_resume(dev);
> > +
> > + if (ret) {
> > + int j;
> > +
> > + for (j = 0; j < i; j++)
> > + pm_generic_suspend(client->sysmmu[j]);
> > + }
> > +
> > + return ret;
> > +}
> > +#endif
> > +
> > +#ifdef CONFIG_PM_RUNTIME
> > +static void sysmmu_restore_state(struct device *sysmmu)
> > +{
> > + struct sysmmu_drvdata *data = dev_get_drvdata(sysmmu);
> > + unsigned long flags;
> > +
> > + spin_lock_irqsave(&data->lock, flags);
> > + data->runtime_active = true;
> > + if (is_sysmmu_active(data))
> > + __sysmmu_enable_nocount(data);
> > + spin_unlock_irqrestore(&data->lock, flags);
> > +}
> > +
> > +static void sysmmu_save_state(struct device *sysmmu)
> > +{
> > + struct sysmmu_drvdata *data = dev_get_drvdata(sysmmu);
> > + unsigned long flags;
> > +
> > + spin_lock_irqsave(&data->lock, flags);
> > + if (is_sysmmu_active(data))
> > + __sysmmu_disable_nocount(data);
> > + data->runtime_active = false;
> > + spin_unlock_irqrestore(&data->lock, flags);
> > +}
> > +
> > +static int sysmmu_pm_genpd_save_state(struct device *dev)
> > +{
> > + struct exynos_iommu_client *client = dev->archdata.iommu;
> > + int (*cb)(struct device *__dev);
> > + int i;
> > +
> > + if (dev->type && dev->type->pm)
> > + cb = dev->type->pm->runtime_suspend;
> > + else if (dev->class && dev->class->pm)
> > + cb = dev->class->pm->runtime_suspend;
> > + else if (dev->bus && dev->bus->pm)
> > + cb = dev->bus->pm->runtime_suspend;
> > + else
> > + cb = NULL;
> > +
> > + if (!cb && dev->driver && dev->driver->pm)
> > + cb = dev->driver->pm->runtime_suspend;
> > +
> > + if (cb) {
> > + int ret;
> > +
> > + ret = cb(dev);
> > + if (ret)
> > + return ret;
> > + }
> > +
> > + for (i = 0; i < client->num_sysmmu; i++)
> > + sysmmu_save_state(client->sysmmu[i]);
> > +
> > + return 0;
> > +}
> > +
> > +static int sysmmu_pm_genpd_restore_state(struct device *dev)
> > +{
> > + struct exynos_iommu_client *client = dev->archdata.iommu;
> > + int (*cb)(struct device *__dev);
> > + int i;
> > +
> > + if (dev->type && dev->type->pm)
> > + cb = dev->type->pm->runtime_resume;
> > + else if (dev->class && dev->class->pm)
> > + cb = dev->class->pm->runtime_resume;
> > + else if (dev->bus && dev->bus->pm)
> > + cb = dev->bus->pm->runtime_resume;
> > + else
> > + cb = NULL;
> > +
> > + if (!cb && dev->driver && dev->driver->pm)
> > + cb = dev->driver->pm->runtime_resume;
> > +
> > + for (i = 0; i < client->num_sysmmu; i++)
> > + sysmmu_restore_state(client->sysmmu[i]);
> > +
> > + if (cb) {
> > + int ret;
> > + ret = cb(dev);
> > + if (ret) {
> > + for (i = 0; i < client->num_sysmmu; i++)
> > + sysmmu_save_state(client->sysmmu[i]);
> > + return ret;
> > + }
> > + }
> > +
> > + return 0;
> > +}
> > +#endif
> > +
> > +#ifdef CONFIG_PM_GENERIC_DOMAINS
> > +struct gpd_dev_ops sysmmu_devpm_ops = {
> > +#ifdef CONFIG_PM_RUNTIME
> > + .save_state = &sysmmu_pm_genpd_save_state,
> > + .restore_state = &sysmmu_pm_genpd_restore_state,
> > +#endif
> > +#ifdef CONFIG_PM_SLEEP
> > + .suspend = &sysmmu_pm_genpd_suspend,
> > + .resume = &sysmmu_pm_genpd_resume,
> > +#endif
> > +};
> > +#endif /* CONFIG_PM_GENERIC_DOMAINS */
> > +
> > +static int sysmmu_hook_driver_register(struct notifier_block *nb,
> > + unsigned long val,
> > + void *p)
> > +{
> > + struct device *dev = p;
> > +
> > + switch (val) {
> > + case BUS_NOTIFY_BIND_DRIVER:
> > + {
> > + int i = 0;
> > + int size = 0;
> > + const __be32 *phandle;
> > + struct exynos_iommu_client *client;
> > +
> > + phandle = of_get_property(dev->of_node, "iommu", &size);
> > + if (!phandle)
> > + break;
> > +
> > + size = size / sizeof(*phandle); /* number of elements */
> > +
> > + client = devm_kzalloc(dev, sizeof(*client) * size, GFP_KERNEL);
> > + if (!client) {
> > + dev_err(dev, "No Memory for exynos_iommu_client\n");
> > + return -ENOMEM;
> > + }
> > +
> > + client->num_sysmmu = size;
> > + client->dev = dev;
> > + INIT_LIST_HEAD(&client->node);
> > + spin_lock_init(&client->lock);
> > +
> > + for (i = 0; i < size; i++) {
> > + struct device_node *np;
> > + struct platform_device *sysmmu;
> > +
> > + /* this always success: see above of_find_property() */
> > + np = of_parse_phandle(dev->of_node, "iommu", i);
> > +
> > + sysmmu = of_find_device_by_node(np);
> > + if (!sysmmu) {
> > + dev_err(dev,
> > + "sysmmu node '%s' is not found\n",
> > + np->name);
> > + break;
> > + }
> > +
> > + client->sysmmu[i] = &sysmmu->dev;
> > + }
> > +
> > + if (i < size) {
> > + while (--i >= 0)
> > + of_node_put(client->sysmmu[i]->of_node);
> > + devm_kfree(dev, client);
> > + return -ENODEV;
> > + }
> > +
> > + i = pm_genpd_add_callbacks(dev, &sysmmu_devpm_ops, NULL);
> > + if (i && (i != -ENOSYS)) {
> > + dev_err(dev,
> > + "Failed to register 'dev_pm_ops' for iommu\n");
> > + devm_kfree(dev, client);
> > + return i;
> > + }
> > +
> > + dev->archdata.iommu = client;
> > + break;
> > + }
> > + case BUS_NOTIFY_BOUND_DRIVER:
> > + {
> > + struct exynos_iommu_client *client = dev->archdata.iommu;
> > + if (dev->archdata.iommu &&
> > + (!pm_runtime_enabled(dev) ||
> > + IS_ERR(dev_to_genpd(dev)))) {
> > + int i;
> > + for (i = 0; i < client->num_sysmmu; i++) {
> > + struct sysmmu_drvdata *data;
> > + pm_runtime_disable(client->sysmmu[i]);
> > + data = dev_get_drvdata(client->sysmmu[i]);
> > + if (!data)
> > + continue;
> > + data->runtime_active =
> > + !pm_runtime_enabled(data->sysmmu);
> > + if (data->runtime_active &&
> > + is_sysmmu_active(data))
> > + __sysmmu_enable_nocount(data);
> > + }
> > + }
> > + break;
> > + }
> > + case BUS_NOTIFY_UNBOUND_DRIVER:
> > + {
> > + if (dev->archdata.iommu) {
> > + __pm_genpd_remove_callbacks(dev, false);
> > +
> > + devm_kfree(dev, dev->archdata.iommu);
> > +
> > + dev->archdata.iommu = NULL;
> > + }
> > + break;
> > + }
> > + } /* switch (val) */
> > +
> > + return 0;
> > +}
> > +
> > +static struct notifier_block sysmmu_notifier = {
> > + .notifier_call = &sysmmu_hook_driver_register,
> > +};
> > +
> > +static int __init exynos_iommu_prepare(void)
> > +{
> > + return bus_register_notifier(&platform_bus_type, &sysmmu_notifier);
> > +}
> > +arch_initcall(exynos_iommu_prepare);