1 /* 2 * PCI Hot Plug Controller Driver for System z 3 * 4 * Copyright 2012 IBM Corp. 5 * 6 * Author(s): 7 * Jan Glauber <jang@linux.vnet.ibm.com> 8 */ 9 10 #define COMPONENT "zPCI hpc" 11 #define pr_fmt(fmt) COMPONENT ": " fmt 12 13 #include <linux/module.h> 14 #include <linux/kernel.h> 15 #include <linux/slab.h> 16 #include <linux/pci.h> 17 #include <linux/pci_hotplug.h> 18 #include <linux/init.h> 19 #include <asm/pci_debug.h> 20 #include <asm/sclp.h> 21 22 #define SLOT_NAME_SIZE 10 23 static LIST_HEAD(s390_hotplug_slot_list); 24 25 MODULE_AUTHOR("Jan Glauber <jang@linux.vnet.ibm.com"); 26 MODULE_DESCRIPTION("Hot Plug PCI Controller for System z"); 27 MODULE_LICENSE("GPL"); 28 29 static int zpci_fn_configured(enum zpci_state state) 30 { 31 return state == ZPCI_FN_STATE_CONFIGURED || 32 state == ZPCI_FN_STATE_ONLINE; 33 } 34 35 /* 36 * struct slot - slot information for each *physical* slot 37 */ 38 struct slot { 39 struct list_head slot_list; 40 struct hotplug_slot *hotplug_slot; 41 struct zpci_dev *zdev; 42 }; 43 44 static inline int slot_configure(struct slot *slot) 45 { 46 int ret = sclp_pci_configure(slot->zdev->fid); 47 48 zpci_dbg(3, "conf fid:%x, rc:%d\n", slot->zdev->fid, ret); 49 if (!ret) 50 slot->zdev->state = ZPCI_FN_STATE_CONFIGURED; 51 52 return ret; 53 } 54 55 static inline int slot_deconfigure(struct slot *slot) 56 { 57 int ret = sclp_pci_deconfigure(slot->zdev->fid); 58 59 zpci_dbg(3, "deconf fid:%x, rc:%d\n", slot->zdev->fid, ret); 60 if (!ret) 61 slot->zdev->state = ZPCI_FN_STATE_STANDBY; 62 63 return ret; 64 } 65 66 static int enable_slot(struct hotplug_slot *hotplug_slot) 67 { 68 struct slot *slot = hotplug_slot->private; 69 int rc; 70 71 if (slot->zdev->state != ZPCI_FN_STATE_STANDBY) 72 return -EIO; 73 74 rc = slot_configure(slot); 75 if (rc) 76 return rc; 77 78 rc = zpci_enable_device(slot->zdev); 79 if (rc) 80 goto out_deconfigure; 81 82 slot->zdev->state = ZPCI_FN_STATE_ONLINE; 83 84 pci_scan_slot(slot->zdev->bus, ZPCI_DEVFN); 85 pci_bus_add_devices(slot->zdev->bus); 86 87 return rc; 88 89 out_deconfigure: 90 slot_deconfigure(slot); 91 return rc; 92 } 93 94 static int disable_slot(struct hotplug_slot *hotplug_slot) 95 { 96 struct slot *slot = hotplug_slot->private; 97 int rc; 98 99 if (!zpci_fn_configured(slot->zdev->state)) 100 return -EIO; 101 102 if (slot->zdev->pdev) 103 pci_stop_and_remove_bus_device(slot->zdev->pdev); 104 105 rc = zpci_disable_device(slot->zdev); 106 if (rc) 107 return rc; 108 109 return slot_deconfigure(slot); 110 } 111 112 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value) 113 { 114 struct slot *slot = hotplug_slot->private; 115 116 switch (slot->zdev->state) { 117 case ZPCI_FN_STATE_STANDBY: 118 *value = 0; 119 break; 120 default: 121 *value = 1; 122 break; 123 } 124 return 0; 125 } 126 127 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value) 128 { 129 /* if the slot exits it always contains a function */ 130 *value = 1; 131 return 0; 132 } 133 134 static void release_slot(struct hotplug_slot *hotplug_slot) 135 { 136 struct slot *slot = hotplug_slot->private; 137 138 pr_debug("%s - physical_slot = %s\n", __func__, hotplug_slot_name(hotplug_slot)); 139 kfree(slot->hotplug_slot->info); 140 kfree(slot->hotplug_slot); 141 kfree(slot); 142 } 143 144 static struct hotplug_slot_ops s390_hotplug_slot_ops = { 145 .enable_slot = enable_slot, 146 .disable_slot = disable_slot, 147 .get_power_status = get_power_status, 148 .get_adapter_status = get_adapter_status, 149 }; 150 151 static int init_pci_slot(struct zpci_dev *zdev) 152 { 153 struct hotplug_slot *hotplug_slot; 154 struct hotplug_slot_info *info; 155 char name[SLOT_NAME_SIZE]; 156 struct slot *slot; 157 int rc; 158 159 if (!zdev) 160 return 0; 161 162 slot = kzalloc(sizeof(*slot), GFP_KERNEL); 163 if (!slot) 164 goto error; 165 166 hotplug_slot = kzalloc(sizeof(*hotplug_slot), GFP_KERNEL); 167 if (!hotplug_slot) 168 goto error_hp; 169 hotplug_slot->private = slot; 170 171 slot->hotplug_slot = hotplug_slot; 172 slot->zdev = zdev; 173 174 info = kzalloc(sizeof(*info), GFP_KERNEL); 175 if (!info) 176 goto error_info; 177 hotplug_slot->info = info; 178 179 hotplug_slot->ops = &s390_hotplug_slot_ops; 180 hotplug_slot->release = &release_slot; 181 182 get_power_status(hotplug_slot, &info->power_status); 183 get_adapter_status(hotplug_slot, &info->adapter_status); 184 185 snprintf(name, SLOT_NAME_SIZE, "%08x", zdev->fid); 186 rc = pci_hp_register(slot->hotplug_slot, zdev->bus, 187 ZPCI_DEVFN, name); 188 if (rc) { 189 pr_err("pci_hp_register failed with error %d\n", rc); 190 goto error_reg; 191 } 192 list_add(&slot->slot_list, &s390_hotplug_slot_list); 193 return 0; 194 195 error_reg: 196 kfree(info); 197 error_info: 198 kfree(hotplug_slot); 199 error_hp: 200 kfree(slot); 201 error: 202 return -ENOMEM; 203 } 204 205 static void exit_pci_slot(struct zpci_dev *zdev) 206 { 207 struct list_head *tmp, *n; 208 struct slot *slot; 209 210 list_for_each_safe(tmp, n, &s390_hotplug_slot_list) { 211 slot = list_entry(tmp, struct slot, slot_list); 212 if (slot->zdev != zdev) 213 continue; 214 list_del(&slot->slot_list); 215 pci_hp_deregister(slot->hotplug_slot); 216 } 217 } 218 219 static struct pci_hp_callback_ops hp_ops = { 220 .create_slot = init_pci_slot, 221 .remove_slot = exit_pci_slot, 222 }; 223 224 static void __init init_pci_slots(void) 225 { 226 struct zpci_dev *zdev; 227 228 /* 229 * Create a structure for each slot, and register that slot 230 * with the pci_hotplug subsystem. 231 */ 232 mutex_lock(&zpci_list_lock); 233 list_for_each_entry(zdev, &zpci_list, entry) { 234 init_pci_slot(zdev); 235 } 236 mutex_unlock(&zpci_list_lock); 237 } 238 239 static void __exit exit_pci_slots(void) 240 { 241 struct list_head *tmp, *n; 242 struct slot *slot; 243 244 /* 245 * Unregister all of our slots with the pci_hotplug subsystem. 246 * Memory will be freed in release_slot() callback after slot's 247 * lifespan is finished. 248 */ 249 list_for_each_safe(tmp, n, &s390_hotplug_slot_list) { 250 slot = list_entry(tmp, struct slot, slot_list); 251 list_del(&slot->slot_list); 252 pci_hp_deregister(slot->hotplug_slot); 253 } 254 } 255 256 static int __init pci_hotplug_s390_init(void) 257 { 258 if (!s390_pci_probe) 259 return -EOPNOTSUPP; 260 261 zpci_register_hp_ops(&hp_ops); 262 init_pci_slots(); 263 264 return 0; 265 } 266 267 static void __exit pci_hotplug_s390_exit(void) 268 { 269 exit_pci_slots(); 270 zpci_deregister_hp_ops(); 271 } 272 273 module_init(pci_hotplug_s390_init); 274 module_exit(pci_hotplug_s390_exit); 275