iommu/of: Refactor of_iommu_configure() for error handling

In preparation for some upcoming cleverness, rework the control flow in
of_iommu_configure() to minimise duplication and improve the propogation
of errors. It's also as good a time as any to switch over from the
now-just-a-compatibility-wrapper of_iommu_get_ops() to using the generic
IOMMU instance interface directly.

Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This commit is contained in:
Robin Murphy 2017-04-10 16:50:56 +05:30 committed by Joerg Roedel
parent 5016bdb796
commit 2a0c57545a

View File

@ -96,6 +96,28 @@ int of_get_dma_window(struct device_node *dn, const char *prefix, int index,
}
EXPORT_SYMBOL_GPL(of_get_dma_window);
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)
return NULL;
err = iommu_fwspec_init(dev, &iommu_spec->np->fwnode, ops);
if (err)
return ERR_PTR(err);
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;
@ -105,10 +127,11 @@ static int __get_pci_rid(struct pci_dev *pdev, u16 alias, void *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
@ -123,56 +146,56 @@ static const struct iommu_ops
* 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;
}
err_put_node:
of_node_put(np);
return NULL;
const struct iommu_ops *of_iommu_configure(struct device *dev,
struct device_node *master_np)
{
const struct iommu_ops *ops;
if (!master_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);
return IS_ERR(ops) ? NULL : ops;
}
static int __init of_iommu_init(void)