[PATCH v8 10/12] iommu/exynos: add bus notifier for registering System MMU
Cho KyongHo
pullip.cho at samsung.com
Fri Aug 2 02:42:35 EDT 2013
> -----Original Message-----
> From: Rahul Sharma [mailto:r.sh.open at gmail.com]
> Sent: Friday, August 02, 2013 2:18 PM
>
> Hi Cho,
>
> On Fri, Jul 26, 2013 at 5:00 PM, Cho KyongHo <pullip.cho at samsung.com> wrote:
> > When a device driver is registered, all constructs to handle System MMU
> > is prepared by bus notifier call.
> >
> > Signed-off-by: Cho KyongHo <pullip.cho at samsung.com>
> > ---
> > 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
> > iommu at lists.linux-foundation.org
> > https://lists.linuxfoundation.org/mailman/listinfo/iommu
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