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 static LIST_HEAD(s390_hotplug_slot_list); 23 24 static int zpci_fn_configured(enum zpci_state state) 25 { 26 return state == ZPCI_FN_STATE_CONFIGURED || 27 state == ZPCI_FN_STATE_ONLINE; 28 } 29 30 /* 31 * struct slot - slot information for each *physical* slot 32 */ 33 struct slot { 34 struct list_head slot_list; 35 struct hotplug_slot *hotplug_slot; 36 struct zpci_dev *zdev; 37 }; 38 39 static inline int slot_configure(struct slot *slot) 40 { 41 int ret = sclp_pci_configure(slot->zdev->fid); 42 43 zpci_dbg(3, "conf fid:%x, rc:%d\n", slot->zdev->fid, ret); 44 if (!ret) 45 slot->zdev->state = ZPCI_FN_STATE_CONFIGURED; 46 47 return ret; 48 } 49 50 static inline int slot_deconfigure(struct slot *slot) 51 { 52 int ret = sclp_pci_deconfigure(slot->zdev->fid); 53 54 zpci_dbg(3, "deconf fid:%x, rc:%d\n", slot->zdev->fid, ret); 55 if (!ret) 56 slot->zdev->state = ZPCI_FN_STATE_STANDBY; 57 58 return ret; 59 } 60 61 static int enable_slot(struct hotplug_slot *hotplug_slot) 62 { 63 struct slot *slot = hotplug_slot->private; 64 int rc; 65 66 if (slot->zdev->state != ZPCI_FN_STATE_STANDBY) 67 return -EIO; 68 69 rc = slot_configure(slot); 70 if (rc) 71 return rc; 72 73 rc = zpci_enable_device(slot->zdev); 74 if (rc) 75 goto out_deconfigure; 76 77 pci_scan_slot(slot->zdev->bus, ZPCI_DEVFN); 78 pci_lock_rescan_remove(); 79 pci_bus_add_devices(slot->zdev->bus); 80 pci_unlock_rescan_remove(); 81 82 return rc; 83 84 out_deconfigure: 85 slot_deconfigure(slot); 86 return rc; 87 } 88 89 static int disable_slot(struct hotplug_slot *hotplug_slot) 90 { 91 struct slot *slot = hotplug_slot->private; 92 struct pci_dev *pdev; 93 int rc; 94 95 if (!zpci_fn_configured(slot->zdev->state)) 96 return -EIO; 97 98 pdev = pci_get_slot(slot->zdev->bus, ZPCI_DEVFN); 99 if (pdev) { 100 pci_stop_and_remove_bus_device_locked(pdev); 101 pci_dev_put(pdev); 102 } 103 104 rc = zpci_disable_device(slot->zdev); 105 if (rc) 106 return rc; 107 108 return slot_deconfigure(slot); 109 } 110 111 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value) 112 { 113 struct slot *slot = hotplug_slot->private; 114 115 switch (slot->zdev->state) { 116 case ZPCI_FN_STATE_STANDBY: 117 *value = 0; 118 break; 119 default: 120 *value = 1; 121 break; 122 } 123 return 0; 124 } 125 126 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value) 127 { 128 /* if the slot exits it always contains a function */ 129 *value = 1; 130 return 0; 131 } 132 133 static void release_slot(struct hotplug_slot *hotplug_slot) 134 { 135 struct slot *slot = hotplug_slot->private; 136 137 kfree(slot->hotplug_slot->info); 138 kfree(slot->hotplug_slot); 139 kfree(slot); 140 } 141 142 static struct hotplug_slot_ops s390_hotplug_slot_ops = { 143 .enable_slot = enable_slot, 144 .disable_slot = disable_slot, 145 .get_power_status = get_power_status, 146 .get_adapter_status = get_adapter_status, 147 }; 148 149 int zpci_init_slot(struct zpci_dev *zdev) 150 { 151 struct hotplug_slot *hotplug_slot; 152 struct hotplug_slot_info *info; 153 char name[SLOT_NAME_SIZE]; 154 struct slot *slot; 155 int rc; 156 157 if (!zdev) 158 return 0; 159 160 slot = kzalloc(sizeof(*slot), GFP_KERNEL); 161 if (!slot) 162 goto error; 163 164 hotplug_slot = kzalloc(sizeof(*hotplug_slot), GFP_KERNEL); 165 if (!hotplug_slot) 166 goto error_hp; 167 hotplug_slot->private = slot; 168 169 slot->hotplug_slot = hotplug_slot; 170 slot->zdev = zdev; 171 172 info = kzalloc(sizeof(*info), GFP_KERNEL); 173 if (!info) 174 goto error_info; 175 hotplug_slot->info = info; 176 177 hotplug_slot->ops = &s390_hotplug_slot_ops; 178 hotplug_slot->release = &release_slot; 179 180 get_power_status(hotplug_slot, &info->power_status); 181 get_adapter_status(hotplug_slot, &info->adapter_status); 182 183 snprintf(name, SLOT_NAME_SIZE, "%08x", zdev->fid); 184 rc = pci_hp_register(slot->hotplug_slot, zdev->bus, 185 ZPCI_DEVFN, name); 186 if (rc) 187 goto error_reg; 188 189 list_add(&slot->slot_list, &s390_hotplug_slot_list); 190 return 0; 191 192 error_reg: 193 kfree(info); 194 error_info: 195 kfree(hotplug_slot); 196 error_hp: 197 kfree(slot); 198 error: 199 return -ENOMEM; 200 } 201 202 void zpci_exit_slot(struct zpci_dev *zdev) 203 { 204 struct slot *slot, *next; 205 206 list_for_each_entry_safe(slot, next, &s390_hotplug_slot_list, 207 slot_list) { 208 if (slot->zdev != zdev) 209 continue; 210 list_del(&slot->slot_list); 211 pci_hp_deregister(slot->hotplug_slot); 212 } 213 } 214