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