1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * PCI Hot Plug Controller Driver for System z 4 * 5 * Copyright 2012 IBM Corp. 6 * 7 * Author(s): 8 * Jan Glauber <jang@linux.vnet.ibm.com> 9 */ 10 11 #define KMSG_COMPONENT "zpci" 12 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt 13 14 #include <linux/kernel.h> 15 #include <linux/slab.h> 16 #include <linux/pci.h> 17 #include <linux/pci_hotplug.h> 18 #include <asm/pci_debug.h> 19 #include <asm/sclp.h> 20 21 #define SLOT_NAME_SIZE 10 22 23 static int zpci_fn_configured(enum zpci_state state) 24 { 25 return state == ZPCI_FN_STATE_CONFIGURED || 26 state == ZPCI_FN_STATE_ONLINE; 27 } 28 29 static inline int zdev_configure(struct zpci_dev *zdev) 30 { 31 int ret = sclp_pci_configure(zdev->fid); 32 33 zpci_dbg(3, "conf fid:%x, rc:%d\n", zdev->fid, ret); 34 if (!ret) 35 zdev->state = ZPCI_FN_STATE_CONFIGURED; 36 37 return ret; 38 } 39 40 static inline int zdev_deconfigure(struct zpci_dev *zdev) 41 { 42 int ret = sclp_pci_deconfigure(zdev->fid); 43 44 zpci_dbg(3, "deconf fid:%x, rc:%d\n", zdev->fid, ret); 45 if (!ret) 46 zdev->state = ZPCI_FN_STATE_STANDBY; 47 48 return ret; 49 } 50 51 static int enable_slot(struct hotplug_slot *hotplug_slot) 52 { 53 struct zpci_dev *zdev = container_of(hotplug_slot, struct zpci_dev, 54 hotplug_slot); 55 struct zpci_bus *zbus = zdev->zbus; 56 int rc; 57 58 if (zdev->state != ZPCI_FN_STATE_STANDBY) 59 return -EIO; 60 61 rc = zdev_configure(zdev); 62 if (rc) 63 return rc; 64 65 rc = zpci_enable_device(zdev); 66 if (rc) 67 goto out_deconfigure; 68 69 pci_scan_slot(zbus->bus, zdev->devfn); 70 pci_lock_rescan_remove(); 71 pci_bus_add_devices(zbus->bus); 72 pci_unlock_rescan_remove(); 73 74 return rc; 75 76 out_deconfigure: 77 zdev_deconfigure(zdev); 78 return rc; 79 } 80 81 static int disable_slot(struct hotplug_slot *hotplug_slot) 82 { 83 struct zpci_dev *zdev = container_of(hotplug_slot, struct zpci_dev, 84 hotplug_slot); 85 struct pci_dev *pdev; 86 struct zpci_bus *zbus = zdev->zbus; 87 int rc; 88 89 if (!zpci_fn_configured(zdev->state)) 90 return -EIO; 91 92 pdev = pci_get_slot(zbus->bus, zdev->devfn); 93 if (pdev) { 94 if (pci_num_vf(pdev)) 95 return -EBUSY; 96 97 pci_stop_and_remove_bus_device_locked(pdev); 98 pci_dev_put(pdev); 99 } 100 101 rc = zpci_disable_device(zdev); 102 if (rc) 103 return rc; 104 105 return zdev_deconfigure(zdev); 106 } 107 108 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value) 109 { 110 struct zpci_dev *zdev = container_of(hotplug_slot, struct zpci_dev, 111 hotplug_slot); 112 113 switch (zdev->state) { 114 case ZPCI_FN_STATE_STANDBY: 115 *value = 0; 116 break; 117 default: 118 *value = 1; 119 break; 120 } 121 return 0; 122 } 123 124 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value) 125 { 126 /* if the slot exits it always contains a function */ 127 *value = 1; 128 return 0; 129 } 130 131 static const struct hotplug_slot_ops s390_hotplug_slot_ops = { 132 .enable_slot = enable_slot, 133 .disable_slot = disable_slot, 134 .get_power_status = get_power_status, 135 .get_adapter_status = get_adapter_status, 136 }; 137 138 int zpci_init_slot(struct zpci_dev *zdev) 139 { 140 char name[SLOT_NAME_SIZE]; 141 struct zpci_bus *zbus = zdev->zbus; 142 143 zdev->hotplug_slot.ops = &s390_hotplug_slot_ops; 144 145 snprintf(name, SLOT_NAME_SIZE, "%08x", zdev->fid); 146 return pci_hp_register(&zdev->hotplug_slot, zbus->bus, 147 zdev->devfn, name); 148 } 149 150 void zpci_exit_slot(struct zpci_dev *zdev) 151 { 152 pci_hp_deregister(&zdev->hotplug_slot); 153 } 154