Runtime power management by exynos-iommu driver independently from master H/W's runtime pm is not useful for power saving since attaching master H/W in probing time turns on its local power endlessly. Thus this removes runtime pm API calls. Runtime PM support is added in the following commits to exynos-iommu driver. Signed-off-by: Cho KyongHo <pullip.cho@xxxxxxxxxxx> --- drivers/iommu/exynos-iommu.c | 337 +++++++++++++++++++++++++----------------- 1 files changed, 201 insertions(+), 136 deletions(-) diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c index 976b88a..d9c5416 100644 --- a/drivers/iommu/exynos-iommu.c +++ b/drivers/iommu/exynos-iommu.c @@ -27,6 +27,8 @@ #include <linux/memblock.h> #include <linux/export.h> #include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/notifier.h> #include <asm/cacheflush.h> #include <asm/pgtable.h> @@ -154,6 +156,12 @@ 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; + struct device *sysmmu; +}; + struct exynos_iommu_domain { struct list_head clients; /* list of sysmmu_drvdata.node */ unsigned long *pgtable; /* lv1 page table, 16KB */ @@ -163,9 +171,8 @@ 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 */ void __iomem *sfrbase; struct clk *clk; struct clk *clk_master; @@ -250,7 +257,6 @@ 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); @@ -310,7 +316,7 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id) itype, base, addr); if (data->domain) ret = report_iommu_fault(data->domain, - data->dev, addr, itype); + data->master, addr, itype); } /* fault is not recovered by fault handler */ @@ -327,125 +333,145 @@ static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id) 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; - - write_lock_irqsave(&data->lock, flags); - - if (!set_sysmmu_inactive(data)) - goto finish; - clk_enable(data->clk_master); __raw_writel(CTRL_DISABLE, data->sfrbase + REG_MMU_CTRL); + __raw_writel(0, data->sfrbase + REG_MMU_CFG); + clk_disable(data->clk); clk_disable(data->clk_master); +} - clk_disable(data->clk); +static bool __sysmmu_disable(struct sysmmu_drvdata *data) +{ + bool disabled; + unsigned long flags; - disabled = true; - data->pgtable = 0; - data->domain = NULL; -finish: - write_unlock_irqrestore(&data->lock, flags); + write_lock_irqsave(&data->lock, flags); + + disabled = set_sysmmu_inactive(data); + + if (disabled) { + data->pgtable = 0; + data->domain = NULL; + + __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, - unsigned long pgtable, struct iommu_domain *domain) +static void __sysmmu_init_config(struct sysmmu_drvdata *data) { - int ret = 0; - unsigned long flags; - unsigned int min; + unsigned long cfg = 0; + int maj, min = 0; - write_lock_irqsave(&data->lock, flags); + maj = __sysmmu_version(data, &min); + if ((maj == 3) && (min > 1)) + cfg |= CFG_FLPDCACHE; - if (!set_sysmmu_active(data)) { - if (WARN_ON(pgtable != data->pgtable)) { - ret = -EBUSY; - set_sysmmu_inactive(data); - } else { - ret = 1; - } - - dev_dbg(data->sysmmu, "Already enabled\n"); - goto finish; - } - - - data->pgtable = pgtable; + __raw_writel(cfg, data->sfrbase + REG_MMU_CFG); +} +static void __sysmmu_enable_nocount(struct sysmmu_drvdata *data) +{ clk_enable(data->clk); clk_enable(data->clk_master); - __sysmmu_set_ptbase(data->sfrbase, pgtable); + __raw_writel(CTRL_BLOCK, data->sfrbase + REG_MMU_CTRL); - if ((__sysmmu_version(data, &min) == 3) && (min > 1)) { - unsigned long cfg; - cfg = __raw_readl(data->sfrbase + REG_MMU_CFG); - __raw_writel(cfg | CFG_FLPDCACHE, data->sfrbase + REG_MMU_CFG); - } + __sysmmu_init_config(data); + + __sysmmu_set_ptbase(data->sfrbase, data->pgtable); __raw_writel(CTRL_ENABLE, data->sfrbase + REG_MMU_CTRL); clk_disable(data->clk_master); +} - data->domain = domain; +static int __sysmmu_enable(struct sysmmu_drvdata *data, + unsigned long pgtable, struct iommu_domain *domain) +{ + int ret = 0; + unsigned long flags; + + write_lock_irqsave(&data->lock, flags); + if (set_sysmmu_active(data)) { + data->pgtable = pgtable; + data->domain = domain; + + __sysmmu_enable_nocount(data); + + dev_dbg(data->sysmmu, "Enabled\n"); + } else { + ret = (pgtable == data->pgtable) ? 1 : -EBUSY; + + dev_dbg(data->sysmmu, "already enabled\n"); + } + + if (WARN_ON(ret < 0)) + set_sysmmu_inactive(data); /* decrement count */ - dev_dbg(data->sysmmu, "Enabled\n"); -finish: write_unlock_irqrestore(&data->lock, flags); return ret; } -int exynos_sysmmu_enable(struct device *dev, unsigned long 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) { - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu); int ret; + struct exynos_iommu_client *client = dev->archdata.iommu; + struct sysmmu_drvdata *data; - BUG_ON(!memblock_is_memory(pgtable)); + if (WARN_ON(!client)) + return -ENODEV; - ret = pm_runtime_get_sync(data->sysmmu); - if (ret < 0) { - dev_dbg(data->sysmmu, "Failed to enable\n"); - return ret; - } + data = dev_get_drvdata(client->sysmmu); - 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 = __sysmmu_enable(data, pgtable, domain); + if (ret >= 0) + data->master = dev; return ret; } +int exynos_sysmmu_enable(struct device *dev, unsigned long pgtable) +{ + BUG_ON(!memblock_is_memory(pgtable)); + + return __exynos_sysmmu_enable(dev, pgtable, NULL); +} + static bool exynos_sysmmu_disable(struct device *dev) { - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu); bool disabled; + struct exynos_iommu_client *client = dev->archdata.iommu; + struct sysmmu_drvdata *data; + + if (WARN_ON(!client)) + return true; - disabled = __exynos_sysmmu_disable(data); - pm_runtime_put(data->sysmmu); + data = dev_get_drvdata(client->sysmmu); + + disabled = __sysmmu_disable(data); + if (disabled) + data->master = NULL; return disabled; } @@ -453,11 +479,13 @@ static bool exynos_sysmmu_disable(struct device *dev) static void sysmmu_tlb_invalidate_entry(struct device *dev, unsigned long iova, size_t size) { + struct exynos_iommu_client *client = dev->archdata.iommu; unsigned long flags; - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu); + struct sysmmu_drvdata *data; - read_lock_irqsave(&data->lock, flags); + data = dev_get_drvdata(client->sysmmu); + read_lock_irqsave(&data->lock, flags); if (is_sysmmu_active(data)) { unsigned int num_inv = 1; /* @@ -477,19 +505,21 @@ static void sysmmu_tlb_invalidate_entry(struct device *dev, unsigned long iova, } clk_disable(data->clk_master); } else { - dev_dbg(data->sysmmu, "Disabled. Skipping invalidating TLB.\n"); + dev_dbg(dev, "disabled. Skipping TLB invalidation @ %#lx\n", + iova); } - read_unlock_irqrestore(&data->lock, flags); } void exynos_sysmmu_tlb_invalidate(struct device *dev) { + struct exynos_iommu_client *client = dev->archdata.iommu; unsigned long flags; - struct sysmmu_drvdata *data = dev_get_drvdata(dev->archdata.iommu); + struct sysmmu_drvdata *data; - read_lock_irqsave(&data->lock, flags); + data = dev_get_drvdata(client->sysmmu); + read_lock_irqsave(&data->lock, flags); if (is_sysmmu_active(data)) { clk_enable(data->clk_master); if (sysmmu_block(data->sfrbase)) { @@ -498,9 +528,8 @@ void exynos_sysmmu_tlb_invalidate(struct device *dev) } clk_disable(data->clk_master); } else { - dev_dbg(data->sysmmu, "Disabled. Skipping invalidating TLB.\n"); + dev_dbg(dev, "disabled. Skipping TLB invalidation\n"); } - read_unlock_irqrestore(&data->lock, flags); } @@ -563,7 +592,6 @@ static int __init exynos_sysmmu_probe(struct platform_device *pdev) data->sysmmu = dev; rwlock_init(&data->lock); - INIT_LIST_HEAD(&data->node); platform_set_drvdata(pdev, data); @@ -637,7 +665,7 @@ 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; @@ -645,11 +673,14 @@ 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++) @@ -666,41 +697,26 @@ 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; } @@ -708,39 +724,27 @@ 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, @@ -870,7 +874,7 @@ 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; @@ -931,8 +935,8 @@ 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, size); + list_for_each_entry(client, &priv->clients, node) + sysmmu_tlb_invalidate_entry(client->dev, iova, size); spin_unlock_irqrestore(&priv->lock, flags); return size; @@ -1017,3 +1021,64 @@ err_reg_driver: return ret; } subsys_initcall(exynos_iommu_init); + +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: + { + struct exynos_iommu_client *client; + struct device_node *np; + struct platform_device *sysmmu; + + np = of_parse_phandle(dev->of_node, "iommu", 0); + if (!np) + break; + + client = devm_kzalloc(dev, sizeof(*client), GFP_KERNEL); + if (!client) { + dev_err(dev, "No Memory for exynos_iommu_client\n"); + return -ENOMEM; + } + + client->dev = dev; + INIT_LIST_HEAD(&client->node); + + sysmmu = of_find_device_by_node(np); + if (!sysmmu) { + dev_err(dev, "sysmmu node '%s' not found\n", np->name); + devm_kfree(dev, client); + return -ENODEV; + } + + client->sysmmu = &sysmmu->dev; + + dev->archdata.iommu = client; + break; + } + case BUS_NOTIFY_UNBOUND_DRIVER: + { + if (dev->archdata.iommu) { + 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 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html