pcibios_get_phb_of_node
dev->dev.of_node = pcibios_get_phb_of_node(dev->bus);
dn = pcibios_get_phb_of_node(bus);
node = pcibios_get_phb_of_node(bus);
struct device_node *pcibios_get_phb_of_node(struct pci_bus *bus);