Jan Glauber | 7441b06 | 2012-11-29 14:35:47 +0100 | [diff] [blame] | 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/sclp.h> |
| 20 | |
| 21 | #define SLOT_NAME_SIZE 10 |
| 22 | static LIST_HEAD(s390_hotplug_slot_list); |
| 23 | |
| 24 | MODULE_AUTHOR("Jan Glauber <jang@linux.vnet.ibm.com"); |
| 25 | MODULE_DESCRIPTION("Hot Plug PCI Controller for System z"); |
| 26 | MODULE_LICENSE("GPL"); |
| 27 | |
| 28 | static int zpci_fn_configured(enum zpci_state state) |
| 29 | { |
| 30 | return state == ZPCI_FN_STATE_CONFIGURED || |
| 31 | state == ZPCI_FN_STATE_ONLINE; |
| 32 | } |
| 33 | |
| 34 | /* |
| 35 | * struct slot - slot information for each *physical* slot |
| 36 | */ |
| 37 | struct slot { |
| 38 | struct list_head slot_list; |
| 39 | struct hotplug_slot *hotplug_slot; |
| 40 | struct zpci_dev *zdev; |
| 41 | }; |
| 42 | |
| 43 | static int enable_slot(struct hotplug_slot *hotplug_slot) |
| 44 | { |
| 45 | struct slot *slot = hotplug_slot->private; |
| 46 | int rc; |
| 47 | |
| 48 | if (slot->zdev->state != ZPCI_FN_STATE_STANDBY) |
| 49 | return -EIO; |
| 50 | |
| 51 | rc = sclp_pci_configure(slot->zdev->fid); |
| 52 | if (!rc) { |
| 53 | slot->zdev->state = ZPCI_FN_STATE_CONFIGURED; |
| 54 | /* automatically scan the device after is was configured */ |
| 55 | zpci_enable_device(slot->zdev); |
| 56 | zpci_scan_device(slot->zdev); |
| 57 | } |
| 58 | return rc; |
| 59 | } |
| 60 | |
| 61 | static int disable_slot(struct hotplug_slot *hotplug_slot) |
| 62 | { |
| 63 | struct slot *slot = hotplug_slot->private; |
| 64 | int rc; |
| 65 | |
| 66 | if (!zpci_fn_configured(slot->zdev->state)) |
| 67 | return -EIO; |
| 68 | |
| 69 | /* TODO: we rely on the user to unbind/remove the device, is that plausible |
| 70 | * or do we need to trigger that here? |
| 71 | */ |
| 72 | rc = sclp_pci_deconfigure(slot->zdev->fid); |
| 73 | if (!rc) { |
| 74 | /* Fixme: better call List-PCI to find the disabled FH |
| 75 | for the FID since the FH should be opaque... */ |
| 76 | slot->zdev->fh &= 0x7fffffff; |
| 77 | slot->zdev->state = ZPCI_FN_STATE_STANDBY; |
| 78 | } |
| 79 | return rc; |
| 80 | } |
| 81 | |
| 82 | static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value) |
| 83 | { |
| 84 | struct slot *slot = hotplug_slot->private; |
| 85 | |
| 86 | switch (slot->zdev->state) { |
| 87 | case ZPCI_FN_STATE_STANDBY: |
| 88 | *value = 0; |
| 89 | break; |
| 90 | default: |
| 91 | *value = 1; |
| 92 | break; |
| 93 | } |
| 94 | return 0; |
| 95 | } |
| 96 | |
| 97 | static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value) |
| 98 | { |
| 99 | /* if the slot exits it always contains a function */ |
| 100 | *value = 1; |
| 101 | return 0; |
| 102 | } |
| 103 | |
| 104 | static void release_slot(struct hotplug_slot *hotplug_slot) |
| 105 | { |
| 106 | struct slot *slot = hotplug_slot->private; |
| 107 | |
| 108 | pr_debug("%s - physical_slot = %s\n", __func__, hotplug_slot_name(hotplug_slot)); |
| 109 | kfree(slot->hotplug_slot->info); |
| 110 | kfree(slot->hotplug_slot); |
| 111 | kfree(slot); |
| 112 | } |
| 113 | |
| 114 | static struct hotplug_slot_ops s390_hotplug_slot_ops = { |
| 115 | .enable_slot = enable_slot, |
| 116 | .disable_slot = disable_slot, |
| 117 | .get_power_status = get_power_status, |
| 118 | .get_adapter_status = get_adapter_status, |
| 119 | }; |
| 120 | |
| 121 | static int init_pci_slot(struct zpci_dev *zdev) |
| 122 | { |
| 123 | struct hotplug_slot *hotplug_slot; |
| 124 | struct hotplug_slot_info *info; |
| 125 | char name[SLOT_NAME_SIZE]; |
| 126 | struct slot *slot; |
| 127 | int rc; |
| 128 | |
| 129 | if (!zdev) |
| 130 | return 0; |
| 131 | |
| 132 | slot = kzalloc(sizeof(*slot), GFP_KERNEL); |
| 133 | if (!slot) |
| 134 | goto error; |
| 135 | |
| 136 | hotplug_slot = kzalloc(sizeof(*hotplug_slot), GFP_KERNEL); |
| 137 | if (!hotplug_slot) |
| 138 | goto error_hp; |
| 139 | hotplug_slot->private = slot; |
| 140 | |
| 141 | slot->hotplug_slot = hotplug_slot; |
| 142 | slot->zdev = zdev; |
| 143 | |
| 144 | info = kzalloc(sizeof(*info), GFP_KERNEL); |
| 145 | if (!info) |
| 146 | goto error_info; |
| 147 | hotplug_slot->info = info; |
| 148 | |
| 149 | hotplug_slot->ops = &s390_hotplug_slot_ops; |
| 150 | hotplug_slot->release = &release_slot; |
| 151 | |
| 152 | get_power_status(hotplug_slot, &info->power_status); |
| 153 | get_adapter_status(hotplug_slot, &info->adapter_status); |
| 154 | |
| 155 | snprintf(name, SLOT_NAME_SIZE, "%08x", zdev->fid); |
| 156 | rc = pci_hp_register(slot->hotplug_slot, zdev->bus, |
| 157 | ZPCI_DEVFN, name); |
| 158 | if (rc) { |
| 159 | pr_err("pci_hp_register failed with error %d\n", rc); |
| 160 | goto error_reg; |
| 161 | } |
| 162 | list_add(&slot->slot_list, &s390_hotplug_slot_list); |
| 163 | return 0; |
| 164 | |
| 165 | error_reg: |
| 166 | kfree(info); |
| 167 | error_info: |
| 168 | kfree(hotplug_slot); |
| 169 | error_hp: |
| 170 | kfree(slot); |
| 171 | error: |
| 172 | return -ENOMEM; |
| 173 | } |
| 174 | |
| 175 | static int __init init_pci_slots(void) |
| 176 | { |
| 177 | struct zpci_dev *zdev; |
| 178 | int device = 0; |
| 179 | |
| 180 | /* |
| 181 | * Create a structure for each slot, and register that slot |
| 182 | * with the pci_hotplug subsystem. |
| 183 | */ |
| 184 | mutex_lock(&zpci_list_lock); |
| 185 | list_for_each_entry(zdev, &zpci_list, entry) { |
| 186 | init_pci_slot(zdev); |
| 187 | device++; |
| 188 | } |
| 189 | |
| 190 | mutex_unlock(&zpci_list_lock); |
| 191 | return (device) ? 0 : -ENODEV; |
| 192 | } |
| 193 | |
| 194 | static void exit_pci_slot(struct zpci_dev *zdev) |
| 195 | { |
| 196 | struct list_head *tmp, *n; |
| 197 | struct slot *slot; |
| 198 | |
| 199 | list_for_each_safe(tmp, n, &s390_hotplug_slot_list) { |
| 200 | slot = list_entry(tmp, struct slot, slot_list); |
| 201 | if (slot->zdev != zdev) |
| 202 | continue; |
| 203 | list_del(&slot->slot_list); |
| 204 | pci_hp_deregister(slot->hotplug_slot); |
| 205 | } |
| 206 | } |
| 207 | |
| 208 | static void __exit exit_pci_slots(void) |
| 209 | { |
| 210 | struct list_head *tmp, *n; |
| 211 | struct slot *slot; |
| 212 | |
| 213 | /* |
| 214 | * Unregister all of our slots with the pci_hotplug subsystem. |
| 215 | * Memory will be freed in release_slot() callback after slot's |
| 216 | * lifespan is finished. |
| 217 | */ |
| 218 | list_for_each_safe(tmp, n, &s390_hotplug_slot_list) { |
| 219 | slot = list_entry(tmp, struct slot, slot_list); |
| 220 | list_del(&slot->slot_list); |
| 221 | pci_hp_deregister(slot->hotplug_slot); |
| 222 | } |
| 223 | } |
| 224 | |
| 225 | static int __init pci_hotplug_s390_init(void) |
| 226 | { |
| 227 | /* |
| 228 | * Do specific initialization stuff for your driver here |
| 229 | * like initializing your controller hardware (if any) and |
| 230 | * determining the number of slots you have in the system |
| 231 | * right now. |
| 232 | */ |
| 233 | |
Heiko Carstens | 1e5635d | 2013-01-30 15:52:16 +0100 | [diff] [blame^] | 234 | if (!s390_pci_probe) |
Jan Glauber | 7441b06 | 2012-11-29 14:35:47 +0100 | [diff] [blame] | 235 | return -EOPNOTSUPP; |
| 236 | |
| 237 | /* register callbacks for slot handling from arch code */ |
| 238 | mutex_lock(&zpci_list_lock); |
| 239 | hotplug_ops.create_slot = init_pci_slot; |
| 240 | hotplug_ops.remove_slot = exit_pci_slot; |
| 241 | mutex_unlock(&zpci_list_lock); |
| 242 | pr_info("registered hotplug slot callbacks\n"); |
| 243 | return init_pci_slots(); |
| 244 | } |
| 245 | |
| 246 | static void __exit pci_hotplug_s390_exit(void) |
| 247 | { |
| 248 | exit_pci_slots(); |
| 249 | } |
| 250 | |
| 251 | module_init(pci_hotplug_s390_init); |
| 252 | module_exit(pci_hotplug_s390_exit); |