@@ -126,6 +126,31 @@ static inline void iort_delete_fwnode(struct acpi_iort_node *node)
spin_unlock(&iort_fwnode_lock);
}
+/**
+ * iort_get_iort_node() - Retrieve iort_node associated with an fwnode
+ *
+ * @fwnode: fwnode associated with device to be looked-up
+ *
+ * Returns: iort_node pointer on success, NULL on failure
+ */
+static inline
+struct acpi_iort_node *iort_get_iort_node(struct fwnode_handle *fwnode)
+{
+ struct iort_fwnode *curr;
+ struct acpi_iort_node *iort_node = NULL;
+
+ spin_lock(&iort_fwnode_lock);
+ list_for_each_entry(curr, &iort_fwnode_list, list) {
+ if (curr->fwnode == fwnode) {
+ iort_node = curr->iort_node;
+ break;
+ }
+ }
+ spin_unlock(&iort_fwnode_lock);
+
+ return iort_node;
+}
+
typedef acpi_status (*iort_find_node_callback)
(struct acpi_iort_node *node, void *context);
@@ -424,9 +449,25 @@ static struct acpi_iort_node *iort_find_dev_node(struct device *dev)
{
struct pci_bus *pbus;
- if (!dev_is_pci(dev))
+ if (!dev_is_pci(dev)) {
+ struct acpi_iort_node *node;
+ /*
+ * scan iort_fwnode_list to see if it's an iort platform
+ * device (such as SMMU, PMCG),its iort node already cached
+ * and associated with fwnode when iort platform devices
+ * were initialized.
+ */
+ node = iort_get_iort_node(dev->fwnode);
+ if (node)
+ return node;
+
+ /*
+ * if not, then it should be a platform device defined in
+ * DSDT/SSDT (with Named Component node in IORT)
+ */
return iort_scan_node(ACPI_IORT_NODE_NAMED_COMPONENT,
iort_match_node_callback, dev);
+ }
/* Find a PCI root bus */
pbus = to_pci_dev(dev)->bus;
Now we have a helper function iort_get_fwnode() which lookup fwnode via iort node for SMMU, but sometimes we just need something exctly the opposite, which means we need to get the iort node via fwnode. For example, we need to get SMMU's iort node when adding support for SMMU MSI, but SMMU is not a named component which has a associated device node in DSDT, that means we can't match the ACPI full path name to get the iort node for SMMU. But with SMMU or other devices in IORT probed as platform device, it created a fwnode to associate with the iort node, so we introduce iort_get_iort_node() to get the iort node via fwnode. This can be extended to PMCG node usage in IORT too. Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org> --- drivers/acpi/arm64/iort.c | 43 ++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 42 insertions(+), 1 deletion(-)