drivers/pci/hotplug/rpadlpar_core.c

   1 /*
   2  * Interface for Dynamic Logical Partitioning of I/O Slots on
   3  * RPA-compliant PPC64 platform.
   4  *
   5  * John Rose <johnrose@austin.ibm.com>
   6  * Linda Xie <lxie@us.ibm.com>
   7  *
   8  * October 2003
   9  *
  10  * Copyright (C) 2003 IBM.
  11  *
  12  *      This program is free software; you can redistribute it and/or
  13  *      modify it under the terms of the GNU General Public License
  14  *      as published by the Free Software Foundation; either version
  15  *      2 of the License, or (at your option) any later version.
  16  */
  17
  18 #undef DEBUG
  19
  20 #include <linux/init.h>
  21 #include <linux/module.h>
  22 #include <linux/pci.h>
  23 #include <linux/string.h>
  24 #include <linux/vmalloc.h>
  25
  26 #include <asm/pci-bridge.h>
  27 #include <linux/mutex.h>
  28 #include <asm/rtas.h>
  29 #include <asm/vio.h>
  30
  31 #include "../pci.h"
  32 #include "rpaphp.h"
  33 #include "rpadlpar.h"
  34
  35 static DEFINE_MUTEX(rpadlpar_mutex);
  36
  37 #define DLPAR_MODULE_NAME "rpadlpar_io"
  38
  39 #define NODE_TYPE_VIO  1
  40 #define NODE_TYPE_SLOT 2
  41 #define NODE_TYPE_PHB  3
  42
  43 static struct device_node *find_vio_slot_node(char *drc_name)
  44 {
  45         struct device_node *parent = of_find_node_by_name(NULL, "vdevice");
  46         struct device_node *dn = NULL;
  47         char *name;
  48         int rc;
  49
  50         if (!parent)
  51                 return NULL;
  52
  53         while ((dn = of_get_next_child(parent, dn))) {
  54                 rc = rpaphp_get_drc_props(dn, NULL, &name, NULL, NULL);
  55                 if ((rc == 0) && (!strcmp(drc_name, name)))
  56                         break;
  57         }
  58
  59         return dn;
  60 }
  61
  62 /* Find dlpar-capable pci node that contains the specified name and type */
  63 static struct device_node *find_php_slot_pci_node(char *drc_name,
  64                                                   char *drc_type)
  65 {
  66         struct device_node *np = NULL;
  67         char *name;
  68         char *type;
  69         int rc;
  70
  71         while ((np = of_find_node_by_name(np, "pci"))) {
  72                 rc = rpaphp_get_drc_props(np, NULL, &name, &type, NULL);
  73                 if (rc == 0)
  74                         if (!strcmp(drc_name, name) && !strcmp(drc_type, type))
  75                                 break;
  76         }
  77
  78         return np;
  79 }
  80
  81 static struct device_node *find_dlpar_node(char *drc_name, int *node_type)
  82 {
  83         struct device_node *dn;
  84
  85         dn = find_php_slot_pci_node(drc_name, "SLOT");
  86         if (dn) {
  87                 *node_type = NODE_TYPE_SLOT;
  88                 return dn;
  89         }
  90
  91         dn = find_php_slot_pci_node(drc_name, "PHB");
  92         if (dn) {
  93                 *node_type = NODE_TYPE_PHB;
  94                 return dn;
  95         }
  96
  97         dn = find_vio_slot_node(drc_name);
  98         if (dn) {
  99                 *node_type = NODE_TYPE_VIO;
 100                 return dn;
 101         }
 102
 103         return NULL;
 104 }
 105
 106 /**
 107  * find_php_slot - return hotplug slot structure for device node
 108  * @dn: target &device_node
 109  *
 110  * This routine will return the hotplug slot structure
 111  * for a given device node. Note that built-in PCI slots
 112  * may be dlpar-able, but not hot-pluggable, so this routine
 113  * will return NULL for built-in PCI slots.
 114  */
 115 static struct slot *find_php_slot(struct device_node *dn)
 116 {
 117         struct list_head *tmp, *n;
 118         struct slot *slot;
 119
 120         list_for_each_safe(tmp, n, &rpaphp_slot_head) {
 121                 slot = list_entry(tmp, struct slot, rpaphp_slot_list);
 122                 if (slot->dn == dn)
 123                         return slot;
 124         }
 125
 126         return NULL;
 127 }
 128
 129 static struct pci_dev *dlpar_find_new_dev(struct pci_bus *parent,
 130                                         struct device_node *dev_dn)
 131 {
 132         struct pci_dev *tmp = NULL;
 133         struct device_node *child_dn;
 134
 135         list_for_each_entry(tmp, &parent->devices, bus_list) {
 136                 child_dn = pci_device_to_OF_node(tmp);
 137                 if (child_dn == dev_dn)
 138                         return tmp;
 139         }
 140         return NULL;
 141 }
 142
 143 static void dlpar_pci_add_bus(struct device_node *dn)
 144 {
 145         struct pci_dn *pdn = PCI_DN(dn);
 146         struct pci_controller *phb = pdn->phb;
 147         struct pci_dev *dev = NULL;
 148
 149         eeh_add_device_tree_early(dn);
 150
 151         /* Add EADS device to PHB bus, adding new entry to bus->devices */
 152         dev = of_create_pci_dev(dn, phb->bus, pdn->devfn);
 153         if (!dev) {
 154                 printk(KERN_ERR "%s: failed to create pci dev for %s\n",
 155                                 __func__, dn->full_name);
 156                 return;
 157         }
 158
 159         /* Scan below the new bridge */
 160         if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
 161             dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
 162                 of_scan_pci_bridge(dev);
 163
 164         /* Map IO space for child bus, which may or may not succeed */
 165         pcibios_map_io_space(dev->subordinate);
 166
 167         /* Finish adding it : resource allocation, adding devices, etc...
 168          * Note that we need to perform the finish pass on the -parent-
 169          * bus of the EADS bridge so the bridge device itself gets
 170          * properly added
 171          */
 172         pcibios_finish_adding_to_bus(phb->bus);
 173 }
 174
 175 static int dlpar_add_pci_slot(char *drc_name, struct device_node *dn)
 176 {
 177         struct pci_dev *dev;
 178         struct pci_controller *phb;
 179
 180         if (pcibios_find_pci_bus(dn))
 181                 return -EINVAL;
 182
 183         /* Add pci bus */
 184         dlpar_pci_add_bus(dn);
 185
 186         /* Confirm new bridge dev was created */
 187         phb = PCI_DN(dn)->phb;
 188         dev = dlpar_find_new_dev(phb->bus, dn);
 189
 190         if (!dev) {
 191                 printk(KERN_ERR "%s: unable to add bus %s\n", __func__,
 192                         drc_name);
 193                 return -EIO;
 194         }
 195
 196         if (dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) {
 197                 printk(KERN_ERR "%s: unexpected header type %d, unable to add bus %s\n",
 198                         __func__, dev->hdr_type, drc_name);
 199                 return -EIO;
 200         }
 201
 202         /* Add hotplug slot */
 203         if (rpaphp_add_slot(dn)) {
 204                 printk(KERN_ERR "%s: unable to add hotplug slot %s\n",
 205                         __func__, drc_name);
 206                 return -EIO;
 207         }
 208         return 0;
 209 }
 210
 211 static int dlpar_remove_phb(char *drc_name, struct device_node *dn)
 212 {
 213         struct slot *slot;
 214         struct pci_dn *pdn;
 215         int rc = 0;
 216
 217         if (!pcibios_find_pci_bus(dn))
 218                 return -EINVAL;
 219
 220         /* If pci slot is hotplugable, use hotplug to remove it */
 221         slot = find_php_slot(dn);
 222         if (slot && rpaphp_deregister_slot(slot)) {
 223                 printk(KERN_ERR "%s: unable to remove hotplug slot %s\n",
 224                        __func__, drc_name);
 225                 return -EIO;
 226         }
 227
 228         pdn = dn->data;
 229         BUG_ON(!pdn || !pdn->phb);
 230         rc = remove_phb_dynamic(pdn->phb);
 231         if (rc < 0)
 232                 return rc;
 233
 234         pdn->phb = NULL;
 235
 236         return 0;
 237 }
 238
 239 static int dlpar_add_phb(char *drc_name, struct device_node *dn)
 240 {
 241         struct pci_controller *phb;
 242
 243         if (PCI_DN(dn) && PCI_DN(dn)->phb) {
 244                 /* PHB already exists */
 245                 return -EINVAL;
 246         }
 247
 248         phb = init_phb_dynamic(dn);
 249         if (!phb)
 250                 return -EIO;
 251
 252         if (rpaphp_add_slot(dn)) {
 253                 printk(KERN_ERR "%s: unable to add hotplug slot %s\n",
 254                         __func__, drc_name);
 255                 return -EIO;
 256         }
 257         return 0;
 258 }
 259
 260 static int dlpar_add_vio_slot(char *drc_name, struct device_node *dn)
 261 {
 262         if (vio_find_node(dn))
 263                 return -EINVAL;
 264
 265         if (!vio_register_device_node(dn)) {
 266                 printk(KERN_ERR
 267                         "%s: failed to register vio node %s\n",
 268                         __func__, drc_name);
 269                 return -EIO;
 270         }
 271         return 0;
 272 }
 273
 274 /**
 275  * dlpar_add_slot - DLPAR add an I/O Slot
 276  * @drc_name: drc-name of newly added slot
 277  *
 278  * Make the hotplug module and the kernel aware of a newly added I/O Slot.
 279  * Return Codes:
 280  * 0                    Success
 281  * -ENODEV              Not a valid drc_name
 282  * -EINVAL              Slot already added
 283  * -ERESTARTSYS         Signalled before obtaining lock
 284  * -EIO                 Internal PCI Error
 285  */
 286 int dlpar_add_slot(char *drc_name)
 287 {
 288         struct device_node *dn = NULL;
 289         int node_type;
 290         int rc = -EIO;
 291
 292         if (mutex_lock_interruptible(&rpadlpar_mutex))
 293                 return -ERESTARTSYS;
 294
 295         /* Find newly added node */
 296         dn = find_dlpar_node(drc_name, &node_type);
 297         if (!dn) {
 298                 rc = -ENODEV;
 299                 goto exit;
 300         }
 301
 302         switch (node_type) {
 303                 case NODE_TYPE_VIO:
 304                         rc = dlpar_add_vio_slot(drc_name, dn);
 305                         break;
 306                 case NODE_TYPE_SLOT:
 307                         rc = dlpar_add_pci_slot(drc_name, dn);
 308                         break;
 309                 case NODE_TYPE_PHB:
 310                         rc = dlpar_add_phb(drc_name, dn);
 311                         break;
 312         }
 313
 314         printk(KERN_INFO "%s: slot %s added\n", DLPAR_MODULE_NAME, drc_name);
 315 exit:
 316         mutex_unlock(&rpadlpar_mutex);
 317         return rc;
 318 }
 319
 320 /**
 321  * dlpar_remove_vio_slot - DLPAR remove a virtual I/O Slot
 322  * @drc_name: drc-name of newly added slot
 323  * @dn: &device_node
 324  *
 325  * Remove the kernel and hotplug representations of an I/O Slot.
 326  * Return Codes:
 327  * 0                    Success
 328  * -EINVAL              Vio dev doesn't exist
 329  */
 330 static int dlpar_remove_vio_slot(char *drc_name, struct device_node *dn)
 331 {
 332         struct vio_dev *vio_dev;
 333
 334         vio_dev = vio_find_node(dn);
 335         if (!vio_dev)
 336                 return -EINVAL;
 337
 338         vio_unregister_device(vio_dev);
 339         return 0;
 340 }
 341
 342 /**
 343  * dlpar_remove_pci_slot - DLPAR remove a PCI I/O Slot
 344  * @drc_name: drc-name of newly added slot
 345  * @dn: &device_node
 346  *
 347  * Remove the kernel and hotplug representations of a PCI I/O Slot.
 348  * Return Codes:
 349  * 0                    Success
 350  * -ENODEV              Not a valid drc_name
 351  * -EIO                 Internal PCI Error
 352  */
 353 int dlpar_remove_pci_slot(char *drc_name, struct device_node *dn)
 354 {
 355         struct pci_bus *bus;
 356         struct slot *slot;
 357
 358         bus = pcibios_find_pci_bus(dn);
 359         if (!bus)
 360                 return -EINVAL;
 361
 362         pr_debug("PCI: Removing PCI slot below EADS bridge %s\n",
 363                  bus->self ? pci_name(bus->self) : "<!PHB!>");
 364
 365         slot = find_php_slot(dn);
 366         if (slot) {
 367                 pr_debug("PCI: Removing hotplug slot for %04x:%02x...\n",
 368                          pci_domain_nr(bus), bus->number);
 369
 370                 if (rpaphp_deregister_slot(slot)) {
 371                         printk(KERN_ERR
 372                                 "%s: unable to remove hotplug slot %s\n",
 373                                 __func__, drc_name);
 374                         return -EIO;
 375                 }
 376         }
 377
 378         /* Remove all devices below slot */
 379         pcibios_remove_pci_devices(bus);
 380
 381         /* Unmap PCI IO space */
 382         if (pcibios_unmap_io_space(bus)) {
 383                 printk(KERN_ERR "%s: failed to unmap bus range\n",
 384                         __func__);
 385                 return -ERANGE;
 386         }
 387
 388         /* Remove the EADS bridge device itself */
 389         BUG_ON(!bus->self);
 390         pr_debug("PCI: Now removing bridge device %s\n", pci_name(bus->self));
 391         eeh_remove_bus_device(bus->self, true);
 392         pci_stop_and_remove_bus_device(bus->self);
 393
 394         return 0;
 395 }
 396
 397 /**
 398  * dlpar_remove_slot - DLPAR remove an I/O Slot
 399  * @drc_name: drc-name of newly added slot
 400  *
 401  * Remove the kernel and hotplug representations of an I/O Slot.
 402  * Return Codes:
 403  * 0                    Success
 404  * -ENODEV              Not a valid drc_name
 405  * -EINVAL              Slot already removed
 406  * -ERESTARTSYS         Signalled before obtaining lock
 407  * -EIO                 Internal Error
 408  */
 409 int dlpar_remove_slot(char *drc_name)
 410 {
 411         struct device_node *dn;
 412         int node_type;
 413         int rc = 0;
 414
 415         if (mutex_lock_interruptible(&rpadlpar_mutex))
 416                 return -ERESTARTSYS;
 417
 418         dn = find_dlpar_node(drc_name, &node_type);
 419         if (!dn) {
 420                 rc = -ENODEV;
 421                 goto exit;
 422         }
 423
 424         switch (node_type) {
 425                 case NODE_TYPE_VIO:
 426                         rc = dlpar_remove_vio_slot(drc_name, dn);
 427                         break;
 428                 case NODE_TYPE_PHB:
 429                         rc = dlpar_remove_phb(drc_name, dn);
 430                         break;
 431                 case NODE_TYPE_SLOT:
 432                         rc = dlpar_remove_pci_slot(drc_name, dn);
 433                         break;
 434         }
 435         vm_unmap_aliases();
 436
 437         printk(KERN_INFO "%s: slot %s removed\n", DLPAR_MODULE_NAME, drc_name);
 438 exit:
 439         mutex_unlock(&rpadlpar_mutex);
 440         return rc;
 441 }
 442
 443 static inline int is_dlpar_capable(void)
 444 {
 445         int rc = rtas_token("ibm,configure-connector");
 446
 447         return (int) (rc != RTAS_UNKNOWN_SERVICE);
 448 }
 449
 450 int __init rpadlpar_io_init(void)
 451 {
 452         int rc = 0;
 453
 454         if (!is_dlpar_capable()) {
 455                 printk(KERN_WARNING "%s: partition not DLPAR capable\n",
 456                         __func__);
 457                 return -EPERM;
 458         }
 459
 460         rc = dlpar_sysfs_init();
 461         return rc;
 462 }
 463
 464 void rpadlpar_io_exit(void)
 465 {
 466         dlpar_sysfs_exit();
 467         return;
 468 }
 469
 470 module_init(rpadlpar_io_init);
 471 module_exit(rpadlpar_io_exit);
 472 MODULE_LICENSE("GPL");