diff options
Diffstat (limited to 'drivers/iommu/iommu.c')
| -rw-r--r-- | drivers/iommu/iommu.c | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 9188eae61e92..1efd6351bbc2 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -1865,17 +1865,36 @@ static int iommu_get_def_domain_type(struct iommu_group *group, static int iommu_get_default_domain_type(struct iommu_group *group, int target_type) { + const struct iommu_ops *ops = group_iommu_ops(group); struct device *untrusted = NULL; struct group_device *gdev; int driver_type = 0; lockdep_assert_held(&group->mutex); + + /* + * ARM32 drivers supporting CONFIG_ARM_DMA_USE_IOMMU can declare an + * identity_domain and it will automatically become their default + * domain. Later on ARM_DMA_USE_IOMMU will install its UNMANAGED domain. + * Override the selection to IDENTITY if we are sure the driver supports + * it. + */ + if (IS_ENABLED(CONFIG_ARM_DMA_USE_IOMMU) && ops->identity_domain) + driver_type = IOMMU_DOMAIN_IDENTITY; + for_each_group_device(group, gdev) { driver_type = iommu_get_def_domain_type(group, gdev->dev, driver_type); - if (dev_is_pci(gdev->dev) && to_pci_dev(gdev->dev)->untrusted) + if (dev_is_pci(gdev->dev) && to_pci_dev(gdev->dev)->untrusted) { + /* + * No ARM32 using systems will set untrusted, it cannot + * work. + */ + if (WARN_ON(IS_ENABLED(CONFIG_ARM_DMA_USE_IOMMU))) + return -1; untrusted = gdev->dev; + } } if (untrusted) { |