1b6ef86e9SUrsula Braun // SPDX-License-Identifier: GPL-2.0 2b6ef86e9SUrsula Braun /* 3b6ef86e9SUrsula Braun * IBM System z PNET ID Support 4b6ef86e9SUrsula Braun * 5b6ef86e9SUrsula Braun * Copyright IBM Corp. 2018 6b6ef86e9SUrsula Braun */ 7b6ef86e9SUrsula Braun 8b6ef86e9SUrsula Braun #include <linux/device.h> 9b6ef86e9SUrsula Braun #include <linux/module.h> 10b6ef86e9SUrsula Braun #include <linux/pci.h> 11b6ef86e9SUrsula Braun #include <linux/types.h> 12b6ef86e9SUrsula Braun #include <asm/ccwgroup.h> 13b6ef86e9SUrsula Braun #include <asm/ccwdev.h> 14b6ef86e9SUrsula Braun #include <asm/pnet.h> 15b6ef86e9SUrsula Braun 16b6ef86e9SUrsula Braun /* 17b6ef86e9SUrsula Braun * Get the PNETIDs from a device. 18b6ef86e9SUrsula Braun * s390 hardware supports the definition of a so-called Physical Network 19b6ef86e9SUrsula Braun * Identifier (short PNETID) per network device port. These PNETIDs can be 20b6ef86e9SUrsula Braun * used to identify network devices that are attached to the same physical 21b6ef86e9SUrsula Braun * network (broadcast domain). 22b6ef86e9SUrsula Braun * 23b6ef86e9SUrsula Braun * The device can be 24b6ef86e9SUrsula Braun * - a ccwgroup device with all bundled subchannels having the same PNETID 25b6ef86e9SUrsula Braun * - a PCI attached network device 26b6ef86e9SUrsula Braun * 27b6ef86e9SUrsula Braun * Returns: 28b6ef86e9SUrsula Braun * 0: PNETIDs extracted from device. 29b6ef86e9SUrsula Braun * -ENOMEM: No memory to extract utility string. 30b6ef86e9SUrsula Braun * -EOPNOTSUPP: Device type without utility string support 31b6ef86e9SUrsula Braun */ 32b6ef86e9SUrsula Braun static int pnet_ids_by_device(struct device *dev, u8 *pnetids) 33b6ef86e9SUrsula Braun { 34b6ef86e9SUrsula Braun memset(pnetids, 0, PNETIDS_LEN); 35b6ef86e9SUrsula Braun if (dev_is_ccwgroup(dev)) { 36b6ef86e9SUrsula Braun struct ccwgroup_device *gdev = to_ccwgroupdev(dev); 37b6ef86e9SUrsula Braun u8 *util_str; 38b6ef86e9SUrsula Braun 39b6ef86e9SUrsula Braun util_str = ccw_device_get_util_str(gdev->cdev[0], 0); 40b6ef86e9SUrsula Braun if (!util_str) 41b6ef86e9SUrsula Braun return -ENOMEM; 42b6ef86e9SUrsula Braun memcpy(pnetids, util_str, PNETIDS_LEN); 43b6ef86e9SUrsula Braun kfree(util_str); 44b6ef86e9SUrsula Braun return 0; 45b6ef86e9SUrsula Braun } 46b6ef86e9SUrsula Braun if (dev_is_pci(dev)) { 47b6ef86e9SUrsula Braun struct zpci_dev *zdev = to_zpci(to_pci_dev(dev)); 48b6ef86e9SUrsula Braun 49b6ef86e9SUrsula Braun memcpy(pnetids, zdev->util_str, sizeof(zdev->util_str)); 50b6ef86e9SUrsula Braun return 0; 51b6ef86e9SUrsula Braun } 52b6ef86e9SUrsula Braun return -EOPNOTSUPP; 53b6ef86e9SUrsula Braun } 54b6ef86e9SUrsula Braun 55b6ef86e9SUrsula Braun /* 56b6ef86e9SUrsula Braun * Extract the pnetid for a device port. 57b6ef86e9SUrsula Braun * 58b6ef86e9SUrsula Braun * Return 0 if a pnetid is found and -ENOENT otherwise. 59b6ef86e9SUrsula Braun */ 60b6ef86e9SUrsula Braun int pnet_id_by_dev_port(struct device *dev, unsigned short port, u8 *pnetid) 61b6ef86e9SUrsula Braun { 62b6ef86e9SUrsula Braun u8 pnetids[MAX_PNETID_PORTS][MAX_PNETID_LEN]; 63b6ef86e9SUrsula Braun static const u8 zero[MAX_PNETID_LEN] = { 0 }; 64b6ef86e9SUrsula Braun int rc = 0; 65b6ef86e9SUrsula Braun 66b6ef86e9SUrsula Braun if (!dev || port >= MAX_PNETID_PORTS) 67b6ef86e9SUrsula Braun return -ENOENT; 68b6ef86e9SUrsula Braun 69b6ef86e9SUrsula Braun if (!pnet_ids_by_device(dev, (u8 *)pnetids) && 70b6ef86e9SUrsula Braun memcmp(pnetids[port], zero, MAX_PNETID_LEN)) 71b6ef86e9SUrsula Braun memcpy(pnetid, pnetids[port], MAX_PNETID_LEN); 72b6ef86e9SUrsula Braun else 73b6ef86e9SUrsula Braun rc = -ENOENT; 74b6ef86e9SUrsula Braun 75b6ef86e9SUrsula Braun return rc; 76b6ef86e9SUrsula Braun } 77b6ef86e9SUrsula Braun EXPORT_SYMBOL_GPL(pnet_id_by_dev_port); 78b6ef86e9SUrsula Braun 79b6ef86e9SUrsula Braun MODULE_DESCRIPTION("pnetid determination from utility strings"); 80b6ef86e9SUrsula Braun MODULE_LICENSE("GPL"); 81