From 9b265536c271163ec4acc140ca0a40a732971cbf Mon Sep 17 00:00:00 2001 From: Marek Szyprowski Date: Mon, 14 Nov 2016 11:08:11 +0100 Subject: iommu/exynos: Add runtime pm support This patch adds runtime pm implementation, which is based on previous suspend/resume code. SYSMMU controller is now being enabled/disabled mainly from the runtime pm callbacks. System sleep callbacks relies on generic pm_runtime_force_suspend/pm_runtime_force_resume helpers. To ensure internal state consistency, additional lock for runtime pm transitions was introduced. Signed-off-by: Marek Szyprowski Signed-off-by: Joerg Roedel --- drivers/iommu/exynos-iommu.c | 45 +++++++++++++++++++++++++++++++++++--------- 1 file changed, 36 insertions(+), 9 deletions(-) (limited to 'drivers/iommu') diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c index 0423dff206d4..22bc7e5c4dcc 100644 --- a/drivers/iommu/exynos-iommu.c +++ b/drivers/iommu/exynos-iommu.c @@ -237,6 +237,7 @@ static const struct sysmmu_fault_info sysmmu_v5_faults[] = { struct exynos_iommu_owner { struct list_head controllers; /* list of sysmmu_drvdata.owner_node */ struct iommu_domain *domain; /* domain this device is attached */ + struct mutex rpm_lock; /* for runtime pm of all sysmmus */ }; /* @@ -632,40 +633,46 @@ static int __init exynos_sysmmu_probe(struct platform_device *pdev) return 0; } -#ifdef CONFIG_PM_SLEEP -static int exynos_sysmmu_suspend(struct device *dev) +static int __maybe_unused exynos_sysmmu_suspend(struct device *dev) { struct sysmmu_drvdata *data = dev_get_drvdata(dev); struct device *master = data->master; if (master) { - pm_runtime_put(dev); + struct exynos_iommu_owner *owner = master->archdata.iommu; + + mutex_lock(&owner->rpm_lock); if (data->domain) { dev_dbg(data->sysmmu, "saving state\n"); __sysmmu_disable(data); } + mutex_unlock(&owner->rpm_lock); } return 0; } -static int exynos_sysmmu_resume(struct device *dev) +static int __maybe_unused exynos_sysmmu_resume(struct device *dev) { struct sysmmu_drvdata *data = dev_get_drvdata(dev); struct device *master = data->master; if (master) { - pm_runtime_get_sync(dev); + struct exynos_iommu_owner *owner = master->archdata.iommu; + + mutex_lock(&owner->rpm_lock); if (data->domain) { dev_dbg(data->sysmmu, "restoring state\n"); __sysmmu_enable(data); } + mutex_unlock(&owner->rpm_lock); } return 0; } -#endif static const struct dev_pm_ops sysmmu_pm_ops = { - SET_LATE_SYSTEM_SLEEP_PM_OPS(exynos_sysmmu_suspend, exynos_sysmmu_resume) + SET_RUNTIME_PM_OPS(exynos_sysmmu_suspend, exynos_sysmmu_resume, NULL) + SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, + pm_runtime_force_resume) }; static const struct of_device_id sysmmu_of_match[] __initconst = { @@ -813,7 +820,15 @@ static void exynos_iommu_detach_device(struct iommu_domain *iommu_domain, return; list_for_each_entry(data, &owner->controllers, owner_node) { - __sysmmu_disable(data); + pm_runtime_put_sync(data->sysmmu); + } + + mutex_lock(&owner->rpm_lock); + + list_for_each_entry(data, &owner->controllers, owner_node) { + pm_runtime_get_noresume(data->sysmmu); + if (pm_runtime_active(data->sysmmu)) + __sysmmu_disable(data); pm_runtime_put(data->sysmmu); } @@ -828,6 +843,7 @@ static void exynos_iommu_detach_device(struct iommu_domain *iommu_domain, owner->domain = NULL; spin_unlock_irqrestore(&domain->lock, flags); + mutex_unlock(&owner->rpm_lock); dev_dbg(dev, "%s: Detached IOMMU with pgtable %pa\n", __func__, &pagetable); @@ -848,6 +864,8 @@ static int exynos_iommu_attach_device(struct iommu_domain *iommu_domain, if (owner->domain) exynos_iommu_detach_device(owner->domain, dev); + mutex_lock(&owner->rpm_lock); + spin_lock_irqsave(&domain->lock, flags); list_for_each_entry(data, &owner->controllers, owner_node) { spin_lock(&data->lock); @@ -859,9 +877,17 @@ static int exynos_iommu_attach_device(struct iommu_domain *iommu_domain, owner->domain = iommu_domain; spin_unlock_irqrestore(&domain->lock, flags); + list_for_each_entry(data, &owner->controllers, owner_node) { + pm_runtime_get_noresume(data->sysmmu); + if (pm_runtime_active(data->sysmmu)) + __sysmmu_enable(data); + pm_runtime_put(data->sysmmu); + } + + mutex_unlock(&owner->rpm_lock); + list_for_each_entry(data, &owner->controllers, owner_node) { pm_runtime_get_sync(data->sysmmu); - __sysmmu_enable(data); } dev_dbg(dev, "%s: Attached IOMMU with pgtable %pa\n", __func__, @@ -1239,6 +1265,7 @@ static int exynos_iommu_of_xlate(struct device *dev, return -ENOMEM; INIT_LIST_HEAD(&owner->controllers); + mutex_init(&owner->rpm_lock); dev->archdata.iommu = owner; } -- cgit v1.2.3-59-g8ed1b