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 #include <linux/init.h>
  18 #include <linux/pci.h>
  19 #include <asm/pci-bridge.h>
  20 #include <asm/semaphore.h>
  21 #include <asm/rtas.h>
  22 #include "../pci.h"
  23 #include "rpaphp.h"
  24 #include "rpadlpar.h"
  25
  26 static DECLARE_MUTEX(rpadlpar_sem);
  27
  28 #define NODE_TYPE_VIO  1
  29 #define NODE_TYPE_SLOT 2
  30 #define NODE_TYPE_PHB  3
  31
  32 static struct device_node *find_php_slot_vio_node(char *drc_name)
  33 {
  34         struct device_node *child;
  35         struct device_node *parent = of_find_node_by_name(NULL, "vdevice");
  36         char *loc_code;
  37
  38         if (!parent)
  39                 return NULL;
  40
  41         for (child = of_get_next_child(parent, NULL);
  42                 child; child = of_get_next_child(parent, child)) {
  43                 loc_code = get_property(child, "ibm,loc-code", NULL);
  44                 if (loc_code && !strncmp(loc_code, drc_name, strlen(drc_name)))
  45                         return child;
  46         }
  47
  48         return NULL;
  49 }
  50
  51 /* Find dlpar-capable pci node that contains the specified name and type */
  52 static struct device_node *find_php_slot_pci_node(char *drc_name,
  53                                                   char *drc_type)
  54 {
  55         struct device_node *np = NULL;
  56         char *name;
  57         char *type;
  58         int rc;
  59
  60         while ((np = of_find_node_by_type(np, "pci"))) {
  61                 rc = rpaphp_get_drc_props(np, NULL, &name, &type, NULL);
  62                 if (rc == 0)
  63                         if (!strcmp(drc_name, name) && !strcmp(drc_type, type))
  64                                 break;
  65         }
  66
  67         return np;
  68 }
  69
  70 static struct device_node *find_newly_added_node(char *drc_name, int *node_type)
  71 {
  72         struct device_node *dn;
  73
  74         dn = find_php_slot_pci_node(drc_name, "SLOT");
  75         if (dn) {
  76                 *node_type = NODE_TYPE_SLOT;
  77                 return dn;
  78         }
  79
  80         dn = find_php_slot_pci_node(drc_name, "PHB");
  81         if (dn) {
  82                 *node_type = NODE_TYPE_PHB;
  83                 return dn;
  84         }
  85
  86         dn = find_php_slot_vio_node(drc_name);
  87         if (dn) {
  88                 *node_type = NODE_TYPE_VIO;
  89                 return dn;
  90         }
  91
  92         return NULL;
  93 }
  94
  95 static struct slot *find_slot(char *drc_name)
  96 {
  97         struct list_head *tmp, *n;
  98         struct slot *slot;
  99
 100         list_for_each_safe(tmp, n, &rpaphp_slot_head) {
 101                 slot = list_entry(tmp, struct slot, rpaphp_slot_list);
 102                 if (strcmp(slot->location, drc_name) == 0)
 103                         return slot;
 104         }
 105
 106         return NULL;
 107 }
 108
 109 static void rpadlpar_claim_one_bus(struct pci_bus *b)
 110 {
 111         struct list_head *ld;
 112         struct pci_bus *child_bus;
 113
 114         for (ld = b->devices.next; ld != &b->devices; ld = ld->next) {
 115                 struct pci_dev *dev = pci_dev_b(ld);
 116                 int i;
 117
 118                 for (i = 0; i < PCI_NUM_RESOURCES; i++) {
 119                         struct resource *r = &dev->resource[i];
 120
 121                         if (r->parent || !r->start || !r->flags)
 122                                 continue;
 123                         rpaphp_claim_resource(dev, i);
 124                 }
 125         }
 126
 127         list_for_each_entry(child_bus, &b->children, node)
 128                 rpadlpar_claim_one_bus(child_bus);
 129 }
 130
 131 static int pci_add_secondary_bus(struct device_node *dn,
 132                 struct pci_dev *bridge_dev)
 133 {
 134         struct pci_controller *hose = dn->phb;
 135         struct pci_bus *child;
 136         u8 sec_busno;
 137
 138         /* Get busno of downstream bus */
 139         pci_read_config_byte(bridge_dev, PCI_SECONDARY_BUS, &sec_busno);
 140
 141         /* Allocate and add to children of bridge_dev->bus */
 142         child = pci_add_new_bus(bridge_dev->bus, bridge_dev, sec_busno);
 143         if (!child) {
 144                 printk(KERN_ERR "%s: could not add secondary bus\n", __FUNCTION__);
 145                 return -ENOMEM;
 146         }
 147
 148         sprintf(child->name, "PCI Bus #%02x", child->number);
 149
 150         /* Fixup subordinate bridge bases and resources */
 151         pcibios_fixup_bus(child);
 152
 153         /* Claim new bus resources */
 154         rpadlpar_claim_one_bus(bridge_dev->bus);
 155
 156         if (hose->last_busno < child->number)
 157                 hose->last_busno = child->number;
 158
 159         dn->bussubno = child->number;
 160
 161         /* ioremap() for child bus, which may or may not succeed */
 162         remap_bus_range(child);
 163
 164         return 0;
 165 }
 166
 167 static struct pci_dev *dlpar_pci_add_bus(struct device_node *dn)
 168 {
 169         struct pci_controller *hose = dn->phb;
 170         struct pci_dev *dev = NULL;
 171
 172         /* Scan phb bus for EADS device, adding new one to bus->devices */
 173         if (!pci_scan_single_device(hose->bus, dn->devfn)) {
 174                 printk(KERN_ERR "%s: found no device on bus\n", __FUNCTION__);
 175                 return NULL;
 176         }
 177
 178         /* Add new devices to global lists.  Register in proc, sysfs. */
 179         pci_bus_add_devices(hose->bus);
 180
 181         /* Confirm new bridge dev was created */
 182         dev = rpaphp_find_pci_dev(dn);
 183         if (!dev) {
 184                 printk(KERN_ERR "%s: failed to add pci device\n", __FUNCTION__);
 185                 return NULL;
 186         }
 187
 188         if (dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) {
 189                 printk(KERN_ERR "%s: unexpected header type %d\n",
 190                         __FUNCTION__, dev->hdr_type);
 191                 return NULL;
 192         }
 193
 194         if (pci_add_secondary_bus(dn, dev))
 195                 return NULL;
 196
 197         return dev;
 198 }
 199
 200 static int dlpar_pci_remove_bus(struct pci_dev *bridge_dev)
 201 {
 202         struct pci_bus *secondary_bus;
 203
 204         if (!bridge_dev) {
 205                 printk(KERN_ERR "%s: unexpected null device\n",
 206                         __FUNCTION__);
 207                 return -EINVAL;
 208         }
 209
 210         secondary_bus = bridge_dev->subordinate;
 211
 212         if (unmap_bus_range(secondary_bus)) {
 213                 printk(KERN_ERR "%s: failed to unmap bus range\n",
 214                         __FUNCTION__);
 215                 return -ERANGE;
 216         }
 217
 218         pci_remove_bus_device(bridge_dev);
 219         return 0;
 220 }
 221
 222 static inline int dlpar_add_pci_slot(char *drc_name, struct device_node *dn)
 223 {
 224         struct pci_dev *dev;
 225
 226         /* Add pci bus */
 227         dev = dlpar_pci_add_bus(dn);
 228         if (!dev) {
 229                 printk(KERN_ERR "%s: unable to add bus %s\n", __FUNCTION__,
 230                         drc_name);
 231                 return -EIO;
 232         }
 233
 234         return 0;
 235 }
 236
 237 static int dlpar_remove_root_bus(struct pci_controller *phb)
 238 {
 239         struct pci_bus *phb_bus;
 240         int rc;
 241
 242         phb_bus = phb->bus;
 243         if (!(list_empty(&phb_bus->children) &&
 244               list_empty(&phb_bus->devices))) {
 245                 return -EBUSY;
 246         }
 247
 248         rc = pcibios_remove_root_bus(phb);
 249         if (rc)
 250                 return -EIO;
 251
 252         device_unregister(phb_bus->bridge);
 253         pci_remove_bus(phb_bus);
 254
 255         return 0;
 256 }
 257
 258 static int dlpar_remove_phb(struct slot *slot)
 259 {
 260         struct pci_controller *phb;
 261         struct device_node *dn;
 262         int rc = 0;
 263
 264         dn = slot->dn;
 265         if (!dn) {
 266                 printk(KERN_ERR "%s: unexpected NULL slot device node\n",
 267                                 __FUNCTION__);
 268                 return -EIO;
 269         }
 270
 271         phb = dn->phb;
 272         if (!phb) {
 273                 printk(KERN_ERR "%s: unexpected NULL phb pointer\n",
 274                                 __FUNCTION__);
 275                 return -EIO;
 276         }
 277
 278         if (rpaphp_remove_slot(slot)) {
 279                 printk(KERN_ERR "%s: unable to remove hotplug slot %s\n",
 280                         __FUNCTION__, slot->location);
 281                 return -EIO;
 282         }
 283
 284         rc = dlpar_remove_root_bus(phb);
 285         if (rc < 0)
 286                 return rc;
 287
 288         return 0;
 289 }
 290
 291 static int dlpar_add_phb(struct device_node *dn)
 292 {
 293         struct pci_controller *phb;
 294
 295         phb = init_phb_dynamic(dn);
 296         if (!phb)
 297                 return -EINVAL;
 298
 299         return 0;
 300 }
 301
 302 /**
 303  * dlpar_add_slot - DLPAR add an I/O Slot
 304  * @drc_name: drc-name of newly added slot
 305  *
 306  * Make the hotplug module and the kernel aware
 307  * of a newly added I/O Slot.
 308  * Return Codes -
 309  * 0                    Success
 310  * -ENODEV              Not a valid drc_name
 311  * -EINVAL              Slot already added
 312  * -ERESTARTSYS         Signalled before obtaining lock
 313  * -EIO                 Internal PCI Error
 314  */
 315 int dlpar_add_slot(char *drc_name)
 316 {
 317         struct device_node *dn = NULL;
 318         int node_type;
 319         int rc = 0;
 320
 321         if (down_interruptible(&rpadlpar_sem))
 322                 return -ERESTARTSYS;
 323
 324         /* Check for existing hotplug slot */
 325         if (find_slot(drc_name)) {
 326                 rc = -EINVAL;
 327                 goto exit;
 328         }
 329
 330         dn = find_newly_added_node(drc_name, &node_type);
 331         if (!dn) {
 332                 rc = -ENODEV;
 333                 goto exit;
 334         }
 335
 336         switch (node_type) {
 337                 case NODE_TYPE_VIO:
 338                         /* Just add hotplug slot */
 339                         break;
 340                 case NODE_TYPE_SLOT:
 341                         rc = dlpar_add_pci_slot(drc_name, dn);
 342                         break;
 343                 case NODE_TYPE_PHB:
 344                         rc = dlpar_add_phb(dn);
 345                         break;
 346                 default:
 347                         printk("%s: unexpected node type\n", __FUNCTION__);
 348                         return -EIO;
 349         }
 350
 351         if (!rc && rpaphp_add_slot(dn)) {
 352                 printk(KERN_ERR "%s: unable to add hotplug slot %s\n",
 353                         __FUNCTION__, drc_name);
 354                 rc = -EIO;
 355         }
 356 exit:
 357         up(&rpadlpar_sem);
 358         return rc;
 359 }
 360
 361 /**
 362  * dlpar_remove_vio_slot - DLPAR remove a virtual I/O Slot
 363  * @drc_name: drc-name of newly added slot
 364  *
 365  * Remove the kernel and hotplug representations
 366  * of an I/O Slot.
 367  * Return Codes:
 368  * 0                    Success
 369  * -EIO                 Internal  Error
 370  */
 371 int dlpar_remove_vio_slot(struct slot *slot, char *drc_name)
 372 {
 373         /* Remove hotplug slot */
 374
 375         if (rpaphp_remove_slot(slot)) {
 376                 printk(KERN_ERR "%s: unable to remove hotplug slot %s\n",
 377                         __FUNCTION__, drc_name);
 378                 return -EIO;
 379         }
 380         return 0;
 381 }
 382
 383 /**
 384  * dlpar_remove_slot - DLPAR remove a PCI I/O Slot
 385  * @drc_name: drc-name of newly added slot
 386  *
 387  * Remove the kernel and hotplug representations
 388  * of a PCI I/O Slot.
 389  * Return Codes:
 390  * 0                    Success
 391  * -ENODEV              Not a valid drc_name
 392  * -EIO                 Internal PCI Error
 393  */
 394 int dlpar_remove_pci_slot(struct slot *slot, char *drc_name)
 395 {
 396         struct pci_dev *bridge_dev;
 397
 398         bridge_dev = slot->bridge;
 399         if (!bridge_dev) {
 400                 printk(KERN_ERR "%s: unexpected null bridge device\n",
 401                         __FUNCTION__);
 402                 return -EIO;
 403         }
 404
 405         /* Remove hotplug slot */
 406         if (rpaphp_remove_slot(slot)) {
 407                 printk(KERN_ERR "%s: unable to remove hotplug slot %s\n",
 408                         __FUNCTION__, drc_name);
 409                 return -EIO;
 410         }
 411
 412         /* Remove pci bus */
 413
 414         if (dlpar_pci_remove_bus(bridge_dev)) {
 415                 printk(KERN_ERR "%s: unable to remove pci bus %s\n",
 416                         __FUNCTION__, drc_name);
 417                 return -EIO;
 418         }
 419         return 0;
 420 }
 421
 422 /**
 423  * dlpar_remove_slot - DLPAR remove an I/O Slot
 424  * @drc_name: drc-name of newly added slot
 425  *
 426  * Remove the kernel and hotplug representations
 427  * of an I/O Slot.
 428  * Return Codes:
 429  * 0                    Success
 430  * -ENODEV              Not a valid drc_name
 431  * -EINVAL              Slot already removed
 432  * -ERESTARTSYS         Signalled before obtaining lock
 433  * -EIO                 Internal Error
 434  */
 435 int dlpar_remove_slot(char *drc_name)
 436 {
 437         struct slot *slot;
 438         int rc = 0;
 439
 440         if (down_interruptible(&rpadlpar_sem))
 441                 return -ERESTARTSYS;
 442
 443         if (!find_php_slot_vio_node(drc_name) &&
 444             !find_php_slot_pci_node(drc_name, "SLOT") &&
 445             !find_php_slot_pci_node(drc_name, "PHB")) {
 446                 rc = -ENODEV;
 447                 goto exit;
 448         }
 449
 450         slot = find_slot(drc_name);
 451         if (!slot) {
 452                 rc = -EINVAL;
 453                 goto exit;
 454         }
 455
 456         if (slot->type == PHB) {
 457                 rc = dlpar_remove_phb(slot);
 458         } else {
 459                 switch (slot->dev_type) {
 460                         case PCI_DEV:
 461                                 rc = dlpar_remove_pci_slot(slot, drc_name);
 462                                 break;
 463
 464                         case VIO_DEV:
 465                                 rc = dlpar_remove_vio_slot(slot, drc_name);
 466                                 break;
 467                 }
 468         }
 469 exit:
 470         up(&rpadlpar_sem);
 471         return rc;
 472 }
 473
 474 static inline int is_dlpar_capable(void)
 475 {
 476         int rc = rtas_token("ibm,configure-connector");
 477
 478         return (int) (rc != RTAS_UNKNOWN_SERVICE);
 479 }
 480
 481 int __init rpadlpar_io_init(void)
 482 {
 483         int rc = 0;
 484
 485         if (!is_dlpar_capable()) {
 486                 printk(KERN_WARNING "%s: partition not DLPAR capable\n",
 487                         __FUNCTION__);
 488                 return -EPERM;
 489         }
 490
 491         rc = dlpar_sysfs_init();
 492         return rc;
 493 }
 494
 495 void rpadlpar_io_exit(void)
 496 {
 497         dlpar_sysfs_exit();
 498         return;
 499 }
 500
 501 module_init(rpadlpar_io_init);
 502 module_exit(rpadlpar_io_exit);
 503 MODULE_LICENSE("GPL");