}
EXPORT_SYMBOL_GPL(of_get_dma_window);
+static bool of_iommu_driver_present(struct device_node *np)
+{
+ /*
+ * If the IOMMU still isn't ready by the time we reach init, assume
+ * it never will be. We don't want to defer indefinitely, nor attempt
+ * to dereference __iommu_of_table after it's been freed.
+ */
+ if (system_state > SYSTEM_BOOTING)
+ return false;
+
+ return of_match_node(&__iommu_of_table, np);
+}
+
+static const struct iommu_ops
+*of_iommu_xlate(struct device *dev, struct of_phandle_args *iommu_spec)
+{
+ const struct iommu_ops *ops;
+ struct fwnode_handle *fwnode = &iommu_spec->np->fwnode;
+ int err;
+
+ ops = iommu_ops_from_fwnode(fwnode);
+ if ((ops && !ops->of_xlate) ||
+ (!ops && !of_iommu_driver_present(iommu_spec->np)))
+ return NULL;
+
+ err = iommu_fwspec_init(dev, &iommu_spec->np->fwnode, ops);
+ if (err)
+ return ERR_PTR(err);
+ /*
+ * The otherwise-empty fwspec handily serves to indicate the specific
+ * IOMMU device we're waiting for, which will be useful if we ever get
+ * a proper probe-ordering dependency mechanism in future.
+ */
+ if (!ops)
+ return ERR_PTR(-EPROBE_DEFER);
+
+ err = ops->of_xlate(dev, iommu_spec);
+ if (err)
+ return ERR_PTR(err);
+
+ return ops;
+}
+
static int __get_pci_rid(struct pci_dev *pdev, u16 alias, void *data)
{
struct of_phandle_args *iommu_spec = data;
}
static const struct iommu_ops
-*of_pci_iommu_configure(struct pci_dev *pdev, struct device_node *bridge_np)
+*of_pci_iommu_init(struct pci_dev *pdev, struct device_node *bridge_np)
{
const struct iommu_ops *ops;
struct of_phandle_args iommu_spec;
+ int err;
/*
* Start by tracing the RID alias down the PCI topology as
* bus into the system beyond, and which IOMMU it ends up at.
*/
iommu_spec.np = NULL;
- if (of_pci_map_rid(bridge_np, iommu_spec.args[0], "iommu-map",
- "iommu-map-mask", &iommu_spec.np, iommu_spec.args))
- return NULL;
+ err = of_pci_map_rid(bridge_np, iommu_spec.args[0], "iommu-map",
+ "iommu-map-mask", &iommu_spec.np,
+ iommu_spec.args);
+ if (err)
+ return err == -ENODEV ? NULL : ERR_PTR(err);
- ops = iommu_ops_from_fwnode(&iommu_spec.np->fwnode);
- if (!ops || !ops->of_xlate ||
- iommu_fwspec_init(&pdev->dev, &iommu_spec.np->fwnode, ops) ||
- ops->of_xlate(&pdev->dev, &iommu_spec))
- ops = NULL;
+ ops = of_iommu_xlate(&pdev->dev, &iommu_spec);
of_node_put(iommu_spec.np);
return ops;
}
-const struct iommu_ops *of_iommu_configure(struct device *dev,
- struct device_node *master_np)
+static const struct iommu_ops
+*of_platform_iommu_init(struct device *dev, struct device_node *np)
{
struct of_phandle_args iommu_spec;
- struct device_node *np;
const struct iommu_ops *ops = NULL;
int idx = 0;
- if (dev_is_pci(dev))
- return of_pci_iommu_configure(to_pci_dev(dev), master_np);
-
/*
* We don't currently walk up the tree looking for a parent IOMMU.
* See the `Notes:' section of
* Documentation/devicetree/bindings/iommu/iommu.txt
*/
- while (!of_parse_phandle_with_args(master_np, "iommus",
- "#iommu-cells", idx,
- &iommu_spec)) {
- np = iommu_spec.np;
- ops = iommu_ops_from_fwnode(&np->fwnode);
-
- if (!ops || !ops->of_xlate ||
- iommu_fwspec_init(dev, &np->fwnode, ops) ||
- ops->of_xlate(dev, &iommu_spec))
- goto err_put_node;
-
- of_node_put(np);
+ while (!of_parse_phandle_with_args(np, "iommus", "#iommu-cells",
+ idx, &iommu_spec)) {
+ ops = of_iommu_xlate(dev, &iommu_spec);
+ of_node_put(iommu_spec.np);
idx++;
+ if (IS_ERR_OR_NULL(ops))
+ break;
}
return ops;
+}
+
+const struct iommu_ops *of_iommu_configure(struct device *dev,
+ struct device_node *master_np)
+{
+ const struct iommu_ops *ops;
+ struct iommu_fwspec *fwspec = dev->iommu_fwspec;
+
+ if (!master_np)
+ return NULL;
+
+ if (fwspec) {
+ if (fwspec->ops)
+ return fwspec->ops;
+
+ /* In the deferred case, start again from scratch */
+ iommu_fwspec_free(dev);
+ }
-err_put_node:
- of_node_put(np);
- return NULL;
+ if (dev_is_pci(dev))
+ ops = of_pci_iommu_init(to_pci_dev(dev), master_np);
+ else
+ ops = of_platform_iommu_init(dev, master_np);
+ /*
+ * If we have reason to believe the IOMMU driver missed the initial
+ * add_device callback for dev, replay it to get things in order.
+ */
+ if (!IS_ERR_OR_NULL(ops) && ops->add_device &&
+ dev->bus && !dev->iommu_group) {
+ int err = ops->add_device(dev);
+
+ if (err)
+ ops = ERR_PTR(err);
+ }
+
+ return ops;
}
static int __init of_iommu_init(void)
for_each_matching_node_and_match(np, matches, &match) {
const of_iommu_init_fn init_fn = match->data;
- if (init_fn(np))
+ if (init_fn && init_fn(np))
pr_err("Failed to initialise IOMMU %s\n",
of_node_full_name(np));
}
projects / linux.git / blobdiff