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 slot *slot, *next;
 118
 119         list_for_each_entry_safe(slot, next, &rpaphp_slot_head,
 120                                  rpaphp_slot_list) {
 121                 if (slot->dn == dn)
 122                         return slot;
 123         }
 124
 125         return NULL;
 126 }
 127
 128 static struct pci_dev *dlpar_find_new_dev(struct pci_bus *parent,
 129                                         struct device_node *dev_dn)
 130 {
 131         struct pci_dev *tmp = NULL;
 132         struct device_node *child_dn;
 133
 134         list_for_each_entry(tmp, &parent->devices, bus_list) {
 135                 child_dn = pci_device_to_OF_node(tmp);
 136                 if (child_dn == dev_dn)
 137                         return tmp;
 138         }
 139         return NULL;
 140 }
 141
 142 static void dlpar_pci_add_bus(struct device_node *dn)
 143 {
 144         struct pci_dn *pdn = PCI_DN(dn);
 145         struct pci_controller *phb = pdn->phb;
 146         struct pci_dev *dev = NULL;
 147
 148         eeh_add_device_tree_early(pdn);
 149
 150         /* Add EADS device to PHB bus, adding new entry to bus->devices */
 151         dev = of_create_pci_dev(dn, phb->bus, pdn->devfn);
 152         if (!dev) {
 153                 printk(KERN_ERR "%s: failed to create pci dev for %s\n",
 154                                 __func__, dn->full_name);
 155                 return;
 156         }
 157
 158         /* Scan below the new bridge */
 159         if (pci_is_bridge(dev))
 160                 of_scan_pci_bridge(dev);
 161
 162         /* Map IO space for child bus, which may or may not succeed */
 163         pcibios_map_io_space(dev->subordinate);
 164
 165         /* Finish adding it : resource allocation, adding devices, etc...
 166          * Note that we need to perform the finish pass on the -parent-
 167          * bus of the EADS bridge so the bridge device itself gets
 168          * properly added
 169          */
 170         pcibios_finish_adding_to_bus(phb->bus);
 171 }
 172
 173 static int dlpar_add_pci_slot(char *drc_name, struct device_node *dn)
 174 {
 175         struct pci_dev *dev;
 176         struct pci_controller *phb;
 177
 178         if (pci_find_bus_by_node(dn))
 179                 return -EINVAL;
 180
 181         /* Add pci bus */
 182         dlpar_pci_add_bus(dn);
 183
 184         /* Confirm new bridge dev was created */
 185         phb = PCI_DN(dn)->phb;
 186         dev = dlpar_find_new_dev(phb->bus, dn);
 187
 188         if (!dev) {
 189                 printk(KERN_ERR "%s: unable to add bus %s\n", __func__,
 190                         drc_name);
 191                 return -EIO;
 192         }
 193
 194         if (dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) {
 195                 printk(KERN_ERR "%s: unexpected header type %d, unable to add bus %s\n",
 196                         __func__, dev->hdr_type, drc_name);
 197                 return -EIO;
 198         }
 199
 200         /* Add hotplug slot */
 201         if (rpaphp_add_slot(dn)) {
 202                 printk(KERN_ERR "%s: unable to add hotplug slot %s\n",
 203                         __func__, drc_name);
 204                 return -EIO;
 205         }
 206         return 0;
 207 }
 208
 209 static int dlpar_remove_phb(char *drc_name, struct device_node *dn)
 210 {
 211         struct slot *slot;
 212         struct pci_dn *pdn;
 213         int rc = 0;
 214
 215         if (!pci_find_bus_by_node(dn))
 216                 return -EINVAL;
 217
 218         /* If pci slot is hotpluggable, use hotplug to remove it */
 219         slot = find_php_slot(dn);
 220         if (slot && rpaphp_deregister_slot(slot)) {
 221                 printk(KERN_ERR "%s: unable to remove hotplug slot %s\n",
 222                        __func__, drc_name);
 223                 return -EIO;
 224         }
 225
 226         pdn = dn->data;
 227         BUG_ON(!pdn || !pdn->phb);
 228         rc = remove_phb_dynamic(pdn->phb);
 229         if (rc < 0)
 230                 return rc;
 231
 232         pdn->phb = NULL;
 233
 234         return 0;
 235 }
 236
 237 static int dlpar_add_phb(char *drc_name, struct device_node *dn)
 238 {
 239         struct pci_controller *phb;
 240
 241         if (PCI_DN(dn) && PCI_DN(dn)->phb) {
 242                 /* PHB already exists */
 243                 return -EINVAL;
 244         }
 245
 246         phb = init_phb_dynamic(dn);
 247         if (!phb)
 248                 return -EIO;
 249
 250         if (rpaphp_add_slot(dn)) {
 251                 printk(KERN_ERR "%s: unable to add hotplug slot %s\n",
 252                         __func__, drc_name);
 253                 return -EIO;
 254         }
 255         return 0;
 256 }
 257
 258 static int dlpar_add_vio_slot(char *drc_name, struct device_node *dn)
 259 {
 260         struct vio_dev *vio_dev;
 261
 262         vio_dev = vio_find_node(dn);
 263         if (vio_dev) {
 264                 put_device(&vio_dev->dev);
 265                 return -EINVAL;
 266         }
 267
 268         if (!vio_register_device_node(dn)) {
 269                 printk(KERN_ERR
 270                         "%s: failed to register vio node %s\n",
 271                         __func__, drc_name);
 272                 return -EIO;
 273         }
 274         return 0;
 275 }
 276
 277 /**
 278  * dlpar_add_slot - DLPAR add an I/O Slot
 279  * @drc_name: drc-name of newly added slot
 280  *
 281  * Make the hotplug module and the kernel aware of a newly added I/O Slot.
 282  * Return Codes:
 283  * 0                    Success
 284  * -ENODEV              Not a valid drc_name
 285  * -EINVAL              Slot already added
 286  * -ERESTARTSYS         Signalled before obtaining lock
 287  * -EIO                 Internal PCI Error
 288  */
 289 int dlpar_add_slot(char *drc_name)
 290 {
 291         struct device_node *dn = NULL;
 292         int node_type;
 293         int rc = -EIO;
 294
 295         if (mutex_lock_interruptible(&rpadlpar_mutex))
 296                 return -ERESTARTSYS;
 297
 298         /* Find newly added node */
 299         dn = find_dlpar_node(drc_name, &node_type);
 300         if (!dn) {
 301                 rc = -ENODEV;
 302                 goto exit;
 303         }
 304
 305         switch (node_type) {
 306                 case NODE_TYPE_VIO:
 307                         rc = dlpar_add_vio_slot(drc_name, dn);
 308                         break;
 309                 case NODE_TYPE_SLOT:
 310                         rc = dlpar_add_pci_slot(drc_name, dn);
 311                         break;
 312                 case NODE_TYPE_PHB:
 313                         rc = dlpar_add_phb(drc_name, dn);
 314                         break;
 315         }
 316
 317         printk(KERN_INFO "%s: slot %s added\n", DLPAR_MODULE_NAME, drc_name);
 318 exit:
 319         mutex_unlock(&rpadlpar_mutex);
 320         return rc;
 321 }
 322
 323 /**
 324  * dlpar_remove_vio_slot - DLPAR remove a virtual I/O Slot
 325  * @drc_name: drc-name of newly added slot
 326  * @dn: &device_node
 327  *
 328  * Remove the kernel and hotplug representations of an I/O Slot.
 329  * Return Codes:
 330  * 0                    Success
 331  * -EINVAL              Vio dev doesn't exist
 332  */
 333 static int dlpar_remove_vio_slot(char *drc_name, struct device_node *dn)
 334 {
 335         struct vio_dev *vio_dev;
 336
 337         vio_dev = vio_find_node(dn);
 338         if (!vio_dev)
 339                 return -EINVAL;
 340
 341         vio_unregister_device(vio_dev);
 342
 343         put_device(&vio_dev->dev);
 344
 345         return 0;
 346 }
 347
 348 /**
 349  * dlpar_remove_pci_slot - DLPAR remove a PCI I/O Slot
 350  * @drc_name: drc-name of newly added slot
 351  * @dn: &device_node
 352  *
 353  * Remove the kernel and hotplug representations of a PCI I/O Slot.
 354  * Return Codes:
 355  * 0                    Success
 356  * -ENODEV              Not a valid drc_name
 357  * -EIO                 Internal PCI Error
 358  */
 359 int dlpar_remove_pci_slot(char *drc_name, struct device_node *dn)
 360 {
 361         struct pci_bus *bus;
 362         struct slot *slot;
 363         int ret = 0;
 364
 365         pci_lock_rescan_remove();
 366
 367         bus = pci_find_bus_by_node(dn);
 368         if (!bus) {
 369                 ret = -EINVAL;
 370                 goto out;
 371         }
 372
 373         pr_debug("PCI: Removing PCI slot below EADS bridge %s\n",
 374                  bus->self ? pci_name(bus->self) : "<!PHB!>");
 375
 376         slot = find_php_slot(dn);
 377         if (slot) {
 378                 pr_debug("PCI: Removing hotplug slot for %04x:%02x...\n",
 379                          pci_domain_nr(bus), bus->number);
 380
 381                 if (rpaphp_deregister_slot(slot)) {
 382                         printk(KERN_ERR
 383                                 "%s: unable to remove hotplug slot %s\n",
 384                                 __func__, drc_name);
 385                         ret = -EIO;
 386                         goto out;
 387                 }
 388         }
 389
 390         /* Remove all devices below slot */
 391         pci_hp_remove_devices(bus);
 392
 393         /* Unmap PCI IO space */
 394         if (pcibios_unmap_io_space(bus)) {
 395                 printk(KERN_ERR "%s: failed to unmap bus range\n",
 396                         __func__);
 397                 ret = -ERANGE;
 398                 goto out;
 399         }
 400
 401         /* Remove the EADS bridge device itself */
 402         BUG_ON(!bus->self);
 403         pr_debug("PCI: Now removing bridge device %s\n", pci_name(bus->self));
 404         pci_stop_and_remove_bus_device(bus->self);
 405
 406  out:
 407         pci_unlock_rescan_remove();
 408         return ret;
 409 }
 410
 411 /**
 412  * dlpar_remove_slot - DLPAR remove an I/O Slot
 413  * @drc_name: drc-name of newly added slot
 414  *
 415  * Remove the kernel and hotplug representations of an I/O Slot.
 416  * Return Codes:
 417  * 0                    Success
 418  * -ENODEV              Not a valid drc_name
 419  * -EINVAL              Slot already removed
 420  * -ERESTARTSYS         Signalled before obtaining lock
 421  * -EIO                 Internal Error
 422  */
 423 int dlpar_remove_slot(char *drc_name)
 424 {
 425         struct device_node *dn;
 426         int node_type;
 427         int rc = 0;
 428
 429         if (mutex_lock_interruptible(&rpadlpar_mutex))
 430                 return -ERESTARTSYS;
 431
 432         dn = find_dlpar_node(drc_name, &node_type);
 433         if (!dn) {
 434                 rc = -ENODEV;
 435                 goto exit;
 436         }
 437
 438         switch (node_type) {
 439                 case NODE_TYPE_VIO:
 440                         rc = dlpar_remove_vio_slot(drc_name, dn);
 441                         break;
 442                 case NODE_TYPE_PHB:
 443                         rc = dlpar_remove_phb(drc_name, dn);
 444                         break;
 445                 case NODE_TYPE_SLOT:
 446                         rc = dlpar_remove_pci_slot(drc_name, dn);
 447                         break;
 448         }
 449         vm_unmap_aliases();
 450
 451         printk(KERN_INFO "%s: slot %s removed\n", DLPAR_MODULE_NAME, drc_name);
 452 exit:
 453         mutex_unlock(&rpadlpar_mutex);
 454         return rc;
 455 }
 456
 457 static inline int is_dlpar_capable(void)
 458 {
 459         int rc = rtas_token("ibm,configure-connector");
 460
 461         return (int) (rc != RTAS_UNKNOWN_SERVICE);
 462 }
 463
 464 int __init rpadlpar_io_init(void)
 465 {
 466         int rc = 0;
 467
 468         if (!is_dlpar_capable()) {
 469                 printk(KERN_WARNING "%s: partition not DLPAR capable\n",
 470                         __func__);
 471                 return -EPERM;
 472         }
 473
 474         rc = dlpar_sysfs_init();
 475         return rc;
 476 }
 477
 478 void rpadlpar_io_exit(void)
 479 {
 480         dlpar_sysfs_exit();
 481         return;
 482 }
 483
 484 module_init(rpadlpar_io_init);
 485 module_exit(rpadlpar_io_exit);
 486 MODULE_LICENSE("GPL");