iommu: Make of_iommu_set/get_ops() DT agnostic
The of_iommu_{set/get}_ops() API is used to associate a device
tree node with a specific set of IOMMU operations. The same
kernel interface is required on systems booting with ACPI, where
devices are not associated with a device tree node, therefore
the interface requires generalization.
The struct device fwnode member represents the fwnode token associated
with the device and the struct it points at is firmware specific;
regardless, it is initialized on both ACPI and DT systems and makes an
ideal candidate to use it to associate a set of IOMMU operations to a
given device, through its struct device.fwnode member pointer, paving
the way for representing per-device iommu_ops (ie an iommu instance
associated with a device).
Convert the DT specific of_iommu_{set/get}_ops() interface to
use struct device.fwnode as a look-up token, making the interface
usable on ACPI systems and rename the data structures and the
registration API so that they are made to represent their usage
more clearly.
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Tomasz Nowicki <tn@semihalf.com>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Tested-by: Tomasz Nowicki <tn@semihalf.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 9a2f196..8d3e847 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -1615,6 +1615,46 @@ int iommu_request_dm_for_dev(struct device *dev)
return ret;
}
+struct iommu_instance {
+ struct list_head list;
+ struct fwnode_handle *fwnode;
+ const struct iommu_ops *ops;
+};
+static LIST_HEAD(iommu_instance_list);
+static DEFINE_SPINLOCK(iommu_instance_lock);
+
+void iommu_register_instance(struct fwnode_handle *fwnode,
+ const struct iommu_ops *ops)
+{
+ struct iommu_instance *iommu = kzalloc(sizeof(*iommu), GFP_KERNEL);
+
+ if (WARN_ON(!iommu))
+ return;
+
+ of_node_get(to_of_node(fwnode));
+ INIT_LIST_HEAD(&iommu->list);
+ iommu->fwnode = fwnode;
+ iommu->ops = ops;
+ spin_lock(&iommu_instance_lock);
+ list_add_tail(&iommu->list, &iommu_instance_list);
+ spin_unlock(&iommu_instance_lock);
+}
+
+const struct iommu_ops *iommu_get_instance(struct fwnode_handle *fwnode)
+{
+ struct iommu_instance *instance;
+ const struct iommu_ops *ops = NULL;
+
+ spin_lock(&iommu_instance_lock);
+ list_for_each_entry(instance, &iommu_instance_list, list)
+ if (instance->fwnode == fwnode) {
+ ops = instance->ops;
+ break;
+ }
+ spin_unlock(&iommu_instance_lock);
+ return ops;
+}
+
int iommu_fwspec_init(struct device *dev, struct fwnode_handle *iommu_fwnode,
const struct iommu_ops *ops)
{