drivers/pci/hotplug/sgi_hotplug.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 2005-2006 Silicon Graphics, Inc. All rights reserved.
   7  *
   8  * This work was based on the 2.4/2.6 kernel development by Dick Reigner.
   9  * Work to add BIOS PROM support was completed by Mike Habeck.
  10  */
  11
  12 #include <linux/init.h>
  13 #include <linux/kernel.h>
  14 #include <linux/module.h>
  15 #include <linux/pci.h>
  16 #include <linux/pci_hotplug.h>
  17 #include <linux/proc_fs.h>
  18 #include <linux/types.h>
  19 #include <linux/mutex.h>
  20
  21 #include <asm/sn/addrs.h>
  22 #include <asm/sn/geo.h>
  23 #include <asm/sn/l1.h>
  24 #include <asm/sn/module.h>
  25 #include <asm/sn/pcibr_provider.h>
  26 #include <asm/sn/pcibus_provider_defs.h>
  27 #include <asm/sn/pcidev.h>
  28 #include <asm/sn/sn_feature_sets.h>
  29 #include <asm/sn/sn_sal.h>
  30 #include <asm/sn/types.h>
  31 #include <linux/acpi.h>
  32 #include <asm/sn/acpi.h>
  33
  34 #include "../pci.h"
  35
  36 MODULE_LICENSE("GPL");
  37 MODULE_AUTHOR("SGI (prarit@sgi.com, dickie@sgi.com, habeck@sgi.com)");
  38 MODULE_DESCRIPTION("SGI Altix Hot Plug PCI Controller Driver");
  39
  40
  41 /* SAL call error codes. Keep in sync with prom header io/include/pcibr.h */
  42 #define PCI_SLOT_ALREADY_UP             2       /* slot already up */
  43 #define PCI_SLOT_ALREADY_DOWN           3       /* slot already down */
  44 #define PCI_L1_ERR                      7       /* L1 console command error */
  45 #define PCI_EMPTY_33MHZ                 15      /* empty 33 MHz bus */
  46
  47
  48 #define PCIIO_ASIC_TYPE_TIOCA           4
  49 #define PCI_L1_QSIZE                    128     /* our L1 message buffer size */
  50 #define SN_MAX_HP_SLOTS                 32      /* max hotplug slots */
  51 #define SN_SLOT_NAME_SIZE               33      /* size of name string */
  52
  53 /* internal list head */
  54 static struct list_head sn_hp_list;
  55
  56 /* hotplug_slot struct's private pointer */
  57 struct slot {
  58         int device_num;
  59         struct pci_bus *pci_bus;
  60         /* this struct for glue internal only */
  61         struct hotplug_slot *hotplug_slot;
  62         struct list_head hp_list;
  63         char physical_path[SN_SLOT_NAME_SIZE];
  64 };
  65
  66 struct pcibr_slot_enable_resp {
  67         int resp_sub_errno;
  68         char resp_l1_msg[PCI_L1_QSIZE + 1];
  69 };
  70
  71 struct pcibr_slot_disable_resp {
  72         int resp_sub_errno;
  73         char resp_l1_msg[PCI_L1_QSIZE + 1];
  74 };
  75
  76 enum sn_pci_req_e {
  77         PCI_REQ_SLOT_ELIGIBLE,
  78         PCI_REQ_SLOT_DISABLE
  79 };
  80
  81 static int enable_slot(struct hotplug_slot *slot);
  82 static int disable_slot(struct hotplug_slot *slot);
  83 static inline int get_power_status(struct hotplug_slot *slot, u8 *value);
  84
  85 static struct hotplug_slot_ops sn_hotplug_slot_ops = {
  86         .owner                  = THIS_MODULE,
  87         .enable_slot            = enable_slot,
  88         .disable_slot           = disable_slot,
  89         .get_power_status       = get_power_status,
  90 };
  91
  92 static DEFINE_MUTEX(sn_hotplug_mutex);
  93
  94 static ssize_t path_show (struct hotplug_slot *bss_hotplug_slot,
  95                           char *buf)
  96 {
  97         int retval = -ENOENT;
  98         struct slot *slot = bss_hotplug_slot->private;
  99
 100         if (!slot)
 101                 return retval;
 102
 103         retval = sprintf (buf, "%s\n", slot->physical_path);
 104         return retval;
 105 }
 106
 107 static struct hotplug_slot_attribute sn_slot_path_attr = __ATTR_RO(path);
 108
 109 static int sn_pci_slot_valid(struct pci_bus *pci_bus, int device)
 110 {
 111         struct pcibus_info *pcibus_info;
 112         u16 busnum, segment, ioboard_type;
 113
 114         pcibus_info = SN_PCIBUS_BUSSOFT_INFO(pci_bus);
 115
 116         /* Check to see if this is a valid slot on 'pci_bus' */
 117         if (!(pcibus_info->pbi_valid_devices & (1 << device)))
 118                 return -EPERM;
 119
 120         ioboard_type = sn_ioboard_to_pci_bus(pci_bus);
 121         busnum = pcibus_info->pbi_buscommon.bs_persist_busnum;
 122         segment = pci_domain_nr(pci_bus) & 0xf;
 123
 124         /* Do not allow hotplug operations on base I/O cards */
 125         if ((ioboard_type == L1_BRICKTYPE_IX ||
 126              ioboard_type == L1_BRICKTYPE_IA) &&
 127             (segment == 1 && busnum == 0 && device != 1))
 128                 return -EPERM;
 129
 130         return 1;
 131 }
 132
 133 static int sn_pci_bus_valid(struct pci_bus *pci_bus)
 134 {
 135         struct pcibus_info *pcibus_info;
 136         u32 asic_type;
 137         u16 ioboard_type;
 138
 139         /* Don't register slots hanging off the TIOCA bus */
 140         pcibus_info = SN_PCIBUS_BUSSOFT_INFO(pci_bus);
 141         asic_type = pcibus_info->pbi_buscommon.bs_asic_type;
 142         if (asic_type == PCIIO_ASIC_TYPE_TIOCA)
 143                 return -EPERM;
 144
 145         /* Only register slots in I/O Bricks that support hotplug */
 146         ioboard_type = sn_ioboard_to_pci_bus(pci_bus);
 147         switch (ioboard_type) {
 148                 case L1_BRICKTYPE_IX:
 149                 case L1_BRICKTYPE_PX:
 150                 case L1_BRICKTYPE_IA:
 151                 case L1_BRICKTYPE_PA:
 152                 case L1_BOARDTYPE_PCIX3SLOT:
 153                         return 1;
 154                         break;
 155                 default:
 156                         return -EPERM;
 157                         break;
 158         }
 159
 160         return -EIO;
 161 }
 162
 163 static int sn_hp_slot_private_alloc(struct hotplug_slot *bss_hotplug_slot,
 164                                     struct pci_bus *pci_bus, int device)
 165 {
 166         struct pcibus_info *pcibus_info;
 167         struct slot *slot;
 168
 169         pcibus_info = SN_PCIBUS_BUSSOFT_INFO(pci_bus);
 170
 171         slot = kzalloc(sizeof(*slot), GFP_KERNEL);
 172         if (!slot)
 173                 return -ENOMEM;
 174         bss_hotplug_slot->private = slot;
 175
 176         bss_hotplug_slot->name = kmalloc(SN_SLOT_NAME_SIZE, GFP_KERNEL);
 177         if (!bss_hotplug_slot->name) {
 178                 kfree(bss_hotplug_slot->private);
 179                 return -ENOMEM;
 180         }
 181
 182         slot->device_num = device;
 183         slot->pci_bus = pci_bus;
 184         sprintf(bss_hotplug_slot->name, "%04x:%02x:%02x",
 185                 pci_domain_nr(pci_bus),
 186                 ((u16)pcibus_info->pbi_buscommon.bs_persist_busnum),
 187                 device + 1);
 188
 189         sn_generate_path(pci_bus, slot->physical_path);
 190
 191         slot->hotplug_slot = bss_hotplug_slot;
 192         list_add(&slot->hp_list, &sn_hp_list);
 193
 194         return 0;
 195 }
 196
 197 static struct hotplug_slot * sn_hp_destroy(void)
 198 {
 199         struct slot *slot;
 200         struct pci_slot *pci_slot;
 201         struct hotplug_slot *bss_hotplug_slot = NULL;
 202
 203         list_for_each_entry(slot, &sn_hp_list, hp_list) {
 204                 bss_hotplug_slot = slot->hotplug_slot;
 205                 pci_slot = bss_hotplug_slot->pci_slot;
 206                 list_del(&((struct slot *)bss_hotplug_slot->private)->
 207                          hp_list);
 208                 sysfs_remove_file(&pci_slot->kobj,
 209                                   &sn_slot_path_attr.attr);
 210                 break;
 211         }
 212         return bss_hotplug_slot;
 213 }
 214
 215 static void sn_bus_free_data(struct pci_dev *dev)
 216 {
 217         struct pci_bus *subordinate_bus;
 218         struct pci_dev *child;
 219
 220         /* Recursively clean up sn_irq_info structs */
 221         if (dev->subordinate) {
 222                 subordinate_bus = dev->subordinate;
 223                 list_for_each_entry(child, &subordinate_bus->devices, bus_list)
 224                         sn_bus_free_data(child);
 225         }
 226         /*
 227          * Some drivers may use dma accesses during the
 228          * driver remove function. We release the sysdata
 229          * areas after the driver remove functions have
 230          * been called.
 231          */
 232         sn_bus_store_sysdata(dev);
 233         sn_pci_unfixup_slot(dev);
 234 }
 235
 236 static int sn_slot_enable(struct hotplug_slot *bss_hotplug_slot,
 237                           int device_num, char **ssdt)
 238 {
 239         struct slot *slot = bss_hotplug_slot->private;
 240         struct pcibus_info *pcibus_info;
 241         struct pcibr_slot_enable_resp resp;
 242         int rc;
 243
 244         pcibus_info = SN_PCIBUS_BUSSOFT_INFO(slot->pci_bus);
 245
 246         /*
 247          * Power-on and initialize the slot in the SN
 248          * PCI infrastructure.
 249          */
 250         rc = sal_pcibr_slot_enable(pcibus_info, device_num, &resp, ssdt);
 251
 252
 253         if (rc == PCI_SLOT_ALREADY_UP) {
 254                 dev_dbg(&slot->pci_bus->self->dev, "is already active\n");
 255                 return 1; /* return 1 to user */
 256         }
 257
 258         if (rc == PCI_L1_ERR) {
 259                 dev_dbg(&slot->pci_bus->self->dev,
 260                         "L1 failure %d with message: %s",
 261                         resp.resp_sub_errno, resp.resp_l1_msg);
 262                 return -EPERM;
 263         }
 264
 265         if (rc) {
 266                 dev_dbg(&slot->pci_bus->self->dev,
 267                         "insert failed with error %d sub-error %d\n",
 268                         rc, resp.resp_sub_errno);
 269                 return -EIO;
 270         }
 271
 272         pcibus_info = SN_PCIBUS_BUSSOFT_INFO(slot->pci_bus);
 273         pcibus_info->pbi_enabled_devices |= (1 << device_num);
 274
 275         return 0;
 276 }
 277
 278 static int sn_slot_disable(struct hotplug_slot *bss_hotplug_slot,
 279                            int device_num, int action)
 280 {
 281         struct slot *slot = bss_hotplug_slot->private;
 282         struct pcibus_info *pcibus_info;
 283         struct pcibr_slot_disable_resp resp;
 284         int rc;
 285
 286         pcibus_info = SN_PCIBUS_BUSSOFT_INFO(slot->pci_bus);
 287
 288         rc = sal_pcibr_slot_disable(pcibus_info, device_num, action, &resp);
 289
 290         if ((action == PCI_REQ_SLOT_ELIGIBLE) &&
 291             (rc == PCI_SLOT_ALREADY_DOWN)) {
 292                 dev_dbg(&slot->pci_bus->self->dev, "Slot %s already inactive\n", slot->physical_path);
 293                 return 1; /* return 1 to user */
 294         }
 295
 296         if ((action == PCI_REQ_SLOT_ELIGIBLE) && (rc == PCI_EMPTY_33MHZ)) {
 297                 dev_dbg(&slot->pci_bus->self->dev,
 298                         "Cannot remove last 33MHz card\n");
 299                 return -EPERM;
 300         }
 301
 302         if ((action == PCI_REQ_SLOT_ELIGIBLE) && (rc == PCI_L1_ERR)) {
 303                 dev_dbg(&slot->pci_bus->self->dev,
 304                         "L1 failure %d with message \n%s\n",
 305                         resp.resp_sub_errno, resp.resp_l1_msg);
 306                 return -EPERM;
 307         }
 308
 309         if ((action == PCI_REQ_SLOT_ELIGIBLE) && rc) {
 310                 dev_dbg(&slot->pci_bus->self->dev,
 311                         "remove failed with error %d sub-error %d\n",
 312                         rc, resp.resp_sub_errno);
 313                 return -EIO;
 314         }
 315
 316         if ((action == PCI_REQ_SLOT_ELIGIBLE) && !rc)
 317                 return 0;
 318
 319         if ((action == PCI_REQ_SLOT_DISABLE) && !rc) {
 320                 pcibus_info = SN_PCIBUS_BUSSOFT_INFO(slot->pci_bus);
 321                 pcibus_info->pbi_enabled_devices &= ~(1 << device_num);
 322                 dev_dbg(&slot->pci_bus->self->dev, "remove successful\n");
 323                 return 0;
 324         }
 325
 326         if ((action == PCI_REQ_SLOT_DISABLE) && rc) {
 327                 dev_dbg(&slot->pci_bus->self->dev,"remove failed rc = %d\n", rc);
 328         }
 329
 330         return rc;
 331 }
 332
 333 /*
 334  * Power up and configure the slot via a SAL call to PROM.
 335  * Scan slot (and any children), do any platform specific fixup,
 336  * and find device driver.
 337  */
 338 static int enable_slot(struct hotplug_slot *bss_hotplug_slot)
 339 {
 340         struct slot *slot = bss_hotplug_slot->private;
 341         struct pci_bus *new_bus = NULL;
 342         struct pci_dev *dev;
 343         int func, num_funcs;
 344         int new_ppb = 0;
 345         int rc;
 346         char *ssdt = NULL;
 347         void pcibios_fixup_device_resources(struct pci_dev *);
 348
 349         /* Serialize the Linux PCI infrastructure */
 350         mutex_lock(&sn_hotplug_mutex);
 351
 352         /*
 353          * Power-on and initialize the slot in the SN
 354          * PCI infrastructure. Also, retrieve the ACPI SSDT
 355          * table for the slot (if ACPI capable PROM).
 356          */
 357         rc = sn_slot_enable(bss_hotplug_slot, slot->device_num, &ssdt);
 358         if (rc) {
 359                 mutex_unlock(&sn_hotplug_mutex);
 360                 return rc;
 361         }
 362
 363         if (ssdt)
 364                 ssdt = __va(ssdt);
 365         /* Add the new SSDT for the slot to the ACPI namespace */
 366         if (SN_ACPI_BASE_SUPPORT() && ssdt) {
 367                 acpi_status ret;
 368
 369                 ret = acpi_load_table((struct acpi_table_header *)ssdt);
 370                 if (ACPI_FAILURE(ret)) {
 371                         printk(KERN_ERR "%s: acpi_load_table failed (0x%x)\n",
 372                                __func__, ret);
 373                         /* try to continue on */
 374                 }
 375         }
 376
 377         num_funcs = pci_scan_slot(slot->pci_bus,
 378                                   PCI_DEVFN(slot->device_num + 1, 0));
 379         if (!num_funcs) {
 380                 dev_dbg(&slot->pci_bus->self->dev, "no device in slot\n");
 381                 mutex_unlock(&sn_hotplug_mutex);
 382                 return -ENODEV;
 383         }
 384
 385         /*
 386          * Map SN resources for all functions on the card
 387          * to the Linux PCI interface and tell the drivers
 388          * about them.
 389          */
 390         for (func = 0; func < num_funcs;  func++) {
 391                 dev = pci_get_slot(slot->pci_bus,
 392                                    PCI_DEVFN(slot->device_num + 1,
 393                                              PCI_FUNC(func)));
 394                 if (dev) {
 395                         /* Need to do slot fixup on PPB before fixup of children
 396                          * (PPB's pcidev_info needs to be in pcidev_info list
 397                          * before child's SN_PCIDEV_INFO() call to setup
 398                          * pdi_host_pcidev_info).
 399                          */
 400                         pcibios_fixup_device_resources(dev);
 401                         if (SN_ACPI_BASE_SUPPORT())
 402                                 sn_acpi_slot_fixup(dev);
 403                         else
 404                                 sn_io_slot_fixup(dev);
 405                         if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
 406                                 unsigned char sec_bus;
 407                                 pci_read_config_byte(dev, PCI_SECONDARY_BUS,
 408                                                      &sec_bus);
 409                                 new_bus = pci_add_new_bus(dev->bus, dev,
 410                                                           sec_bus);
 411                                 pci_scan_child_bus(new_bus);
 412                                 new_ppb = 1;
 413                         }
 414                         pci_dev_put(dev);
 415                 }
 416         }
 417
 418         /*
 419          * Add the slot's devices to the ACPI infrastructure */
 420         if (SN_ACPI_BASE_SUPPORT() && ssdt) {
 421                 unsigned long adr;
 422                 struct acpi_device *pdevice;
 423                 struct acpi_device *device;
 424                 acpi_handle phandle;
 425                 acpi_handle chandle = NULL;
 426                 acpi_handle rethandle;
 427                 acpi_status ret;
 428
 429                 phandle = PCI_CONTROLLER(slot->pci_bus)->acpi_handle;
 430
 431                 if (acpi_bus_get_device(phandle, &pdevice)) {
 432                         dev_dbg(&slot->pci_bus->self->dev,
 433                                 "no parent device, assuming NULL\n");
 434                         pdevice = NULL;
 435                 }
 436
 437                 /*
 438                  * Walk the rootbus node's immediate children looking for
 439                  * the slot's device node(s). There can be more than
 440                  * one for multifunction devices.
 441                  */
 442                 for (;;) {
 443                         rethandle = NULL;
 444                         ret = acpi_get_next_object(ACPI_TYPE_DEVICE,
 445                                                    phandle, chandle,
 446                                                    &rethandle);
 447
 448                         if (ret == AE_NOT_FOUND || rethandle == NULL)
 449                                 break;
 450
 451                         chandle = rethandle;
 452
 453                         ret = acpi_evaluate_integer(chandle, METHOD_NAME__ADR,
 454                                                     NULL, &adr);
 455
 456                         if (ACPI_SUCCESS(ret) &&
 457                             (adr>>16) == (slot->device_num + 1)) {
 458
 459                                 ret = acpi_bus_add(&device, pdevice, chandle,
 460                                                    ACPI_BUS_TYPE_DEVICE);
 461                                 if (ACPI_FAILURE(ret)) {
 462                                         printk(KERN_ERR "%s: acpi_bus_add "
 463                                                "failed (0x%x) for slot %d "
 464                                                "func %d\n", __func__,
 465                                                ret, (int)(adr>>16),
 466                                                (int)(adr&0xffff));
 467                                         /* try to continue on */
 468                                 } else {
 469                                         acpi_bus_start(device);
 470                                 }
 471                         }
 472                 }
 473         }
 474
 475         /* Call the driver for the new device */
 476         pci_bus_add_devices(slot->pci_bus);
 477         /* Call the drivers for the new devices subordinate to PPB */
 478         if (new_ppb)
 479                 pci_bus_add_devices(new_bus);
 480
 481         mutex_unlock(&sn_hotplug_mutex);
 482
 483         if (rc == 0)
 484                 dev_dbg(&slot->pci_bus->self->dev,
 485                         "insert operation successful\n");
 486         else
 487                 dev_dbg(&slot->pci_bus->self->dev,
 488                         "insert operation failed rc = %d\n", rc);
 489
 490         return rc;
 491 }
 492
 493 static int disable_slot(struct hotplug_slot *bss_hotplug_slot)
 494 {
 495         struct slot *slot = bss_hotplug_slot->private;
 496         struct pci_dev *dev;
 497         int func;
 498         int rc;
 499         acpi_owner_id ssdt_id = 0;
 500
 501         /* Acquire update access to the bus */
 502         mutex_lock(&sn_hotplug_mutex);
 503
 504         /* is it okay to bring this slot down? */
 505         rc = sn_slot_disable(bss_hotplug_slot, slot->device_num,
 506                              PCI_REQ_SLOT_ELIGIBLE);
 507         if (rc)
 508                 goto leaving;
 509
 510         /* free the ACPI resources for the slot */
 511         if (SN_ACPI_BASE_SUPPORT() &&
 512             PCI_CONTROLLER(slot->pci_bus)->acpi_handle) {
 513                 unsigned long adr;
 514                 struct acpi_device *device;
 515                 acpi_handle phandle;
 516                 acpi_handle chandle = NULL;
 517                 acpi_handle rethandle;
 518                 acpi_status ret;
 519
 520                 /* Get the rootbus node pointer */
 521                 phandle = PCI_CONTROLLER(slot->pci_bus)->acpi_handle;
 522
 523                 /*
 524                  * Walk the rootbus node's immediate children looking for
 525                  * the slot's device node(s). There can be more than
 526                  * one for multifunction devices.
 527                  */
 528                 for (;;) {
 529                         rethandle = NULL;
 530                         ret = acpi_get_next_object(ACPI_TYPE_DEVICE,
 531                                                    phandle, chandle,
 532                                                    &rethandle);
 533
 534                         if (ret == AE_NOT_FOUND || rethandle == NULL)
 535                                 break;
 536
 537                         chandle = rethandle;
 538
 539                         ret = acpi_evaluate_integer(chandle,
 540                                                     METHOD_NAME__ADR,
 541                                                     NULL, &adr);
 542                         if (ACPI_SUCCESS(ret) &&
 543                             (adr>>16) == (slot->device_num + 1)) {
 544                                 /* retain the owner id */
 545                                 acpi_get_id(chandle, &ssdt_id);
 546
 547                                 ret = acpi_bus_get_device(chandle,
 548                                                           &device);
 549                                 if (ACPI_SUCCESS(ret))
 550                                         acpi_bus_trim(device, 1);
 551                         }
 552                 }
 553
 554         }
 555
 556         /* Free the SN resources assigned to the Linux device.*/
 557         for (func = 0; func < 8;  func++) {
 558                 dev = pci_get_slot(slot->pci_bus,
 559                                    PCI_DEVFN(slot->device_num + 1,
 560                                              PCI_FUNC(func)));
 561                 if (dev) {
 562                         sn_bus_free_data(dev);
 563                         pci_remove_bus_device(dev);
 564                         pci_dev_put(dev);
 565                 }
 566         }
 567
 568         /* Remove the SSDT for the slot from the ACPI namespace */
 569         if (SN_ACPI_BASE_SUPPORT() && ssdt_id) {
 570                 acpi_status ret;
 571                 ret = acpi_unload_table_id(ssdt_id);
 572                 if (ACPI_FAILURE(ret)) {
 573                         printk(KERN_ERR "%s: acpi_unload_table_id "
 574                                "failed (0x%x) for id %d\n",
 575                                __func__, ret, ssdt_id);
 576                         /* try to continue on */
 577                 }
 578         }
 579
 580         /* free the collected sysdata pointers */
 581         sn_bus_free_sysdata();
 582
 583         /* Deactivate slot */
 584         rc = sn_slot_disable(bss_hotplug_slot, slot->device_num,
 585                              PCI_REQ_SLOT_DISABLE);
 586  leaving:
 587         /* Release the bus lock */
 588         mutex_unlock(&sn_hotplug_mutex);
 589
 590         return rc;
 591 }
 592
 593 static inline int get_power_status(struct hotplug_slot *bss_hotplug_slot,
 594                                    u8 *value)
 595 {
 596         struct slot *slot = bss_hotplug_slot->private;
 597         struct pcibus_info *pcibus_info;
 598         u32 power;
 599
 600         pcibus_info = SN_PCIBUS_BUSSOFT_INFO(slot->pci_bus);
 601         mutex_lock(&sn_hotplug_mutex);
 602         power = pcibus_info->pbi_enabled_devices & (1 << slot->device_num);
 603         *value = power ? 1 : 0;
 604         mutex_unlock(&sn_hotplug_mutex);
 605         return 0;
 606 }
 607
 608 static void sn_release_slot(struct hotplug_slot *bss_hotplug_slot)
 609 {
 610         kfree(bss_hotplug_slot->info);
 611         kfree(bss_hotplug_slot->name);
 612         kfree(bss_hotplug_slot->private);
 613         kfree(bss_hotplug_slot);
 614 }
 615
 616 static int sn_hotplug_slot_register(struct pci_bus *pci_bus)
 617 {
 618         int device;
 619         struct pci_slot *pci_slot;
 620         struct hotplug_slot *bss_hotplug_slot;
 621         int rc = 0;
 622
 623         /*
 624          * Currently only four devices are supported,
 625          * in the future there maybe more -- up to 32.
 626          */
 627
 628         for (device = 0; device < SN_MAX_HP_SLOTS ; device++) {
 629                 if (sn_pci_slot_valid(pci_bus, device) != 1)
 630                         continue;
 631
 632                 bss_hotplug_slot = kzalloc(sizeof(*bss_hotplug_slot),
 633                                            GFP_KERNEL);
 634                 if (!bss_hotplug_slot) {
 635                         rc = -ENOMEM;
 636                         goto alloc_err;
 637                 }
 638
 639                 bss_hotplug_slot->info =
 640                         kzalloc(sizeof(struct hotplug_slot_info),
 641                                 GFP_KERNEL);
 642                 if (!bss_hotplug_slot->info) {
 643                         rc = -ENOMEM;
 644                         goto alloc_err;
 645                 }
 646
 647                 if (sn_hp_slot_private_alloc(bss_hotplug_slot,
 648                                              pci_bus, device)) {
 649                         rc = -ENOMEM;
 650                         goto alloc_err;
 651                 }
 652
 653                 bss_hotplug_slot->ops = &sn_hotplug_slot_ops;
 654                 bss_hotplug_slot->release = &sn_release_slot;
 655
 656                 rc = pci_hp_register(bss_hotplug_slot, pci_bus, device);
 657                 if (rc)
 658                         goto register_err;
 659
 660                 pci_slot = bss_hotplug_slot->pci_slot;
 661                 rc = sysfs_create_file(&pci_slot->kobj,
 662                                        &sn_slot_path_attr.attr);
 663                 if (rc)
 664                         goto register_err;
 665         }
 666         dev_dbg(&pci_bus->self->dev, "Registered bus with hotplug\n");
 667         return rc;
 668
 669 register_err:
 670         dev_dbg(&pci_bus->self->dev, "bus failed to register with err = %d\n",
 671                 rc);
 672
 673 alloc_err:
 674         if (rc == -ENOMEM)
 675                 dev_dbg(&pci_bus->self->dev, "Memory allocation error\n");
 676
 677         /* destroy THIS element */
 678         if (bss_hotplug_slot)
 679                 sn_release_slot(bss_hotplug_slot);
 680
 681         /* destroy anything else on the list */
 682         while ((bss_hotplug_slot = sn_hp_destroy()))
 683                 pci_hp_deregister(bss_hotplug_slot);
 684
 685         return rc;
 686 }
 687
 688 static int sn_pci_hotplug_init(void)
 689 {
 690         struct pci_bus *pci_bus = NULL;
 691         int rc;
 692         int registered = 0;
 693
 694         if (!sn_prom_feature_available(PRF_HOTPLUG_SUPPORT)) {
 695                 printk(KERN_ERR "%s: PROM version does not support hotplug.\n",
 696                        __func__);
 697                 return -EPERM;
 698         }
 699
 700         INIT_LIST_HEAD(&sn_hp_list);
 701
 702         while ((pci_bus = pci_find_next_bus(pci_bus))) {
 703                 if (!pci_bus->sysdata)
 704                         continue;
 705
 706                 rc = sn_pci_bus_valid(pci_bus);
 707                 if (rc != 1) {
 708                         dev_dbg(&pci_bus->self->dev, "not a valid hotplug bus\n");
 709                         continue;
 710                 }
 711                 dev_dbg(&pci_bus->self->dev, "valid hotplug bus\n");
 712
 713                 rc = sn_hotplug_slot_register(pci_bus);
 714                 if (!rc) {
 715                         registered = 1;
 716                 } else {
 717                         registered = 0;
 718                         break;
 719                 }
 720         }
 721
 722         return registered == 1 ? 0 : -ENODEV;
 723 }
 724
 725 static void sn_pci_hotplug_exit(void)
 726 {
 727         struct hotplug_slot *bss_hotplug_slot;
 728
 729         while ((bss_hotplug_slot = sn_hp_destroy()))
 730                 pci_hp_deregister(bss_hotplug_slot);
 731
 732         if (!list_empty(&sn_hp_list))
 733                 printk(KERN_ERR "%s: internal list is not empty\n", __FILE__);
 734 }
 735
 736 module_init(sn_pci_hotplug_init);
 737 module_exit(sn_pci_hotplug_exit);