[COMMON] iommu/exynos: add attach/detach device

Client device is attached to domain by attach_device.
It enables sysmmu for all clients that attached to domain.
Client device is detached from domain by detach_device.
All enabled sysmmus for clients are disabled.

Change-Id: Ib261369344516ee034a3fae0498137f983ca5bd6
Signed-off-by: Janghyuck Kim <janghyuck.kim@samsung.com>

diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index b970b114a132f39657b4d707a110a575b9839a6e..33b2fe7fc4916f3cd54efd9d32852220d540aa8f 100644 (file)
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -217,6 +217,42 @@ static void sysmmu_disable_from_master(struct device *master)
        spin_unlock_irqrestore(&owner->lock, flags);
 }
 
+static int __sysmmu_enable(struct sysmmu_drvdata *drvdata, phys_addr_t pgtable)
+{
+       /* DUMMY */
+       return 0;
+}
+
+static int sysmmu_enable_from_master(struct device *master,
+                               struct exynos_iommu_domain *domain)
+{
+       int ret = 0;
+       unsigned long flags;
+       struct exynos_iommu_owner *owner = master->archdata.iommu;
+       struct sysmmu_list_data *list;
+       struct sysmmu_drvdata *drvdata;
+       phys_addr_t pgtable = virt_to_phys(domain->pgtable);
+
+       spin_lock_irqsave(&owner->lock, flags);
+       list_for_each_entry(list, &owner->sysmmu_list, node) {
+               drvdata = dev_get_drvdata(list->sysmmu);
+               ret = __sysmmu_enable(drvdata, pgtable);
+
+               /* rollback if enable is failed */
+               if (ret < 0) {
+                       list_for_each_entry_continue_reverse(list,
+                                               &owner->sysmmu_list, node) {
+                               drvdata = dev_get_drvdata(list->sysmmu);
+                               __sysmmu_disable(drvdata);
+                       }
+                       break;
+               }
+       }
+       spin_unlock_irqrestore(&owner->lock, flags);
+
+       return ret;
+}
+
 #ifdef CONFIG_PM_SLEEP
 static int exynos_sysmmu_suspend(struct device *dev)
 {
@@ -318,12 +354,71 @@ static void exynos_iommu_domain_free(struct iommu_domain *iommu_domain)
 static int exynos_iommu_attach_device(struct iommu_domain *iommu_domain,
                                   struct device *master)
 {
-       return 0;
+       struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
+       struct exynos_iommu_owner *owner;
+       phys_addr_t pagetable = virt_to_phys(domain->pgtable);
+       unsigned long flags;
+       int ret = -ENODEV;
+
+       if (!has_sysmmu(master)) {
+               dev_err(master, "has no sysmmu device.\n");
+               return -ENODEV;
+       }
+
+       spin_lock_irqsave(&domain->lock, flags);
+       list_for_each_entry(owner, &domain->clients_list, client) {
+               if (owner->master == master) {
+                       dev_err(master, "is already attached!\n");
+                       spin_unlock_irqrestore(&domain->lock, flags);
+                       return -EEXIST;
+               }
+       }
+       /* owner is under domain. */
+       owner = master->archdata.iommu;
+       list_add_tail(&owner->client, &domain->clients_list);
+       spin_unlock_irqrestore(&domain->lock, flags);
+
+       ret = sysmmu_enable_from_master(master, domain);
+       if (ret < 0) {
+               dev_err(master, "%s: Failed to attach IOMMU with pgtable %pa\n",
+                                       __func__, &pagetable);
+               return ret;
+       }
+
+       dev_dbg(master, "%s: Attached IOMMU with pgtable %pa %s\n",
+               __func__, &pagetable, (ret == 0) ? "" : ", again");
+
+       return ret;
 }
 
 static void exynos_iommu_detach_device(struct iommu_domain *iommu_domain,
                                    struct device *master)
 {
+       struct exynos_iommu_domain *domain = to_exynos_domain(iommu_domain);
+       phys_addr_t pagetable = virt_to_phys(domain->pgtable);
+       struct exynos_iommu_owner *owner, *tmp_owner;
+       unsigned long flags;
+       bool found = false;
+
+       if (!has_sysmmu(master))
+               return;
+
+       spin_lock_irqsave(&domain->lock, flags);
+       list_for_each_entry_safe(owner, tmp_owner,
+                               &domain->clients_list, client) {
+               if (owner->master == master) {
+                       sysmmu_disable_from_master(master);
+                       list_del_init(&owner->client);
+                       found = true;
+               }
+       }
+       spin_unlock_irqrestore(&domain->lock, flags);
+
+       if (found)
+               dev_dbg(master, "%s: Detached IOMMU with pgtable %pa\n",
+                                       __func__, &pagetable);
+       else
+               dev_err(master, "%s: No IOMMU is attached\n", __func__);
 }
 
 static int exynos_iommu_map(struct iommu_domain *iommu_domain,