pnv_pci_get_device_tree
extern int pnv_pci_get_device_tree(uint32_t phandle, void *buf, uint64_t len);
EXPORT_SYMBOL_GPL(pnv_pci_get_device_tree);
ret = pnv_pci_get_device_tree(php_slot->dn->phandle, fdt1, 0x10000);