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 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/proc_fs.h>
  17 #include <linux/types.h>
  18
  19 #include <asm/sn/addrs.h>
  20 #include <asm/sn/l1.h>
  21 #include <asm/sn/module.h>
  22 #include <asm/sn/pcibr_provider.h>
  23 #include <asm/sn/pcibus_provider_defs.h>
  24 #include <asm/sn/pcidev.h>
  25 #include <asm/sn/sn_sal.h>
  26 #include <asm/sn/types.h>
  27
  28 #include "../pci.h"
  29 #include "pci_hotplug.h"
  30
  31 MODULE_LICENSE("GPL");
  32 MODULE_AUTHOR("SGI (prarit@sgi.com, dickie@sgi.com, habeck@sgi.com)");
  33 MODULE_DESCRIPTION("SGI Altix Hot Plug PCI Controller Driver");
  34
  35 #define PCIIO_ASIC_TYPE_TIOCA     4
  36 #define PCI_SLOT_ALREADY_UP       2     /* slot already up */
  37 #define PCI_SLOT_ALREADY_DOWN     3     /* slot already down */
  38 #define PCI_L1_ERR                7     /* L1 console command error */
  39 #define PCI_EMPTY_33MHZ          15     /* empty 33 MHz bus */
  40 #define PCI_L1_QSIZE            128     /* our L1 message buffer size */
  41 #define SN_MAX_HP_SLOTS          32     /* max number of hotplug slots */
  42 #define SGI_HOTPLUG_PROM_REV    0x0420  /* Min. required PROM version */
  43
  44 /* internal list head */
  45 static struct list_head sn_hp_list;
  46
  47 /* hotplug_slot struct's private pointer */
  48 struct slot {
  49         int device_num;
  50         struct pci_bus *pci_bus;
  51         /* this struct for glue internal only */
  52         struct hotplug_slot *hotplug_slot;
  53         struct list_head hp_list;
  54 };
  55
  56 struct pcibr_slot_enable_resp {
  57         int resp_sub_errno;
  58         char resp_l1_msg[PCI_L1_QSIZE + 1];
  59 };
  60
  61 struct pcibr_slot_disable_resp {
  62         int resp_sub_errno;
  63         char resp_l1_msg[PCI_L1_QSIZE + 1];
  64 };
  65
  66 enum sn_pci_req_e {
  67         PCI_REQ_SLOT_ELIGIBLE,
  68         PCI_REQ_SLOT_DISABLE
  69 };
  70
  71 static int enable_slot(struct hotplug_slot *slot);
  72 static int disable_slot(struct hotplug_slot *slot);
  73 static int get_power_status(struct hotplug_slot *slot, u8 *value);
  74
  75 static struct hotplug_slot_ops sn_hotplug_slot_ops = {
  76         .owner                  = THIS_MODULE,
  77         .enable_slot            = enable_slot,
  78         .disable_slot           = disable_slot,
  79         .get_power_status       = get_power_status,
  80 };
  81
  82 static DECLARE_MUTEX(sn_hotplug_sem);
  83
  84 static int sn_pci_slot_valid(struct pci_bus *pci_bus, int device)
  85 {
  86         struct pcibus_info *pcibus_info;
  87         int bricktype;
  88         int bus_num;
  89
  90         pcibus_info = SN_PCIBUS_BUSSOFT_INFO(pci_bus);
  91
  92         /* Check to see if this is a valid slot on 'pci_bus' */
  93         if (!(pcibus_info->pbi_valid_devices & (1 << device)))
  94                 return -EPERM;
  95
  96         bricktype = MODULE_GET_BTYPE(pcibus_info->pbi_moduleid);
  97         bus_num = pcibus_info->pbi_buscommon.bs_persist_busnum & 0xf;
  98
  99         /* Do not allow hotplug operations on base I/O cards */
 100         if ((bricktype == L1_BRICKTYPE_IX ||  bricktype == L1_BRICKTYPE_IA) &&
 101             (bus_num == 1 && device != 1))
 102                 return -EPERM;
 103
 104         return 1;
 105 }
 106
 107 static int sn_pci_bus_valid(struct pci_bus *pci_bus)
 108 {
 109         struct pcibus_info *pcibus_info;
 110         int asic_type;
 111         int bricktype;
 112
 113         pcibus_info = SN_PCIBUS_BUSSOFT_INFO(pci_bus);
 114
 115         /* Don't register slots hanging off the TIOCA bus */
 116         asic_type = pcibus_info->pbi_buscommon.bs_asic_type;
 117         if (asic_type == PCIIO_ASIC_TYPE_TIOCA)
 118                 return -EPERM;
 119
 120         /* Only register slots in I/O Bricks that support hotplug */
 121         bricktype = MODULE_GET_BTYPE(pcibus_info->pbi_moduleid);
 122         switch (bricktype) {
 123         case L1_BRICKTYPE_IX:
 124         case L1_BRICKTYPE_PX:
 125         case L1_BRICKTYPE_IA:
 126         case L1_BRICKTYPE_PA:
 127                 return 1;
 128                 break;
 129         default:
 130                 return -EPERM;
 131                 break;
 132         }
 133
 134         return -EIO;
 135 }
 136
 137 static int sn_hp_slot_private_alloc(struct hotplug_slot *bss_hotplug_slot,
 138                                     struct pci_bus *pci_bus, int device)
 139 {
 140         struct pcibus_info *pcibus_info;
 141         struct slot *slot;
 142
 143         pcibus_info = SN_PCIBUS_BUSSOFT_INFO(pci_bus);
 144
 145         bss_hotplug_slot->private = kcalloc(1, sizeof(struct slot),
 146                                             GFP_KERNEL);
 147         if (!bss_hotplug_slot->private)
 148                 return -ENOMEM;
 149         slot = (struct slot *)bss_hotplug_slot->private;
 150
 151         bss_hotplug_slot->name = kmalloc(33, GFP_KERNEL);
 152         if (!bss_hotplug_slot->name) {
 153                 kfree(bss_hotplug_slot->private);
 154                 return -ENOMEM;
 155         }
 156
 157         slot->device_num = device;
 158         slot->pci_bus = pci_bus;
 159
 160         sprintf(bss_hotplug_slot->name, "module_%c%c%c%c%.2d_b_%d_s_%d",
 161                 '0'+RACK_GET_CLASS(MODULE_GET_RACK(pcibus_info->pbi_moduleid)),
 162                 '0'+RACK_GET_GROUP(MODULE_GET_RACK(pcibus_info->pbi_moduleid)),
 163                 '0'+RACK_GET_NUM(MODULE_GET_RACK(pcibus_info->pbi_moduleid)),
 164                 MODULE_GET_BTCHAR(pcibus_info->pbi_moduleid),
 165                 MODULE_GET_BPOS(pcibus_info->pbi_moduleid),
 166                 ((int)pcibus_info->pbi_buscommon.bs_persist_busnum) & 0xf,
 167                 device + 1);
 168
 169         slot->hotplug_slot = bss_hotplug_slot;
 170         list_add(&slot->hp_list, &sn_hp_list);
 171
 172         return 0;
 173 }
 174
 175 static struct hotplug_slot * sn_hp_destroy(void)
 176 {
 177         struct slot *slot;
 178         struct list_head *list;
 179         struct hotplug_slot *bss_hotplug_slot = NULL;
 180
 181         list_for_each(list, &sn_hp_list) {
 182                 slot = list_entry(list, struct slot, hp_list);
 183                 bss_hotplug_slot = slot->hotplug_slot;
 184                 list_del(&((struct slot *)bss_hotplug_slot->private)->
 185                          hp_list);
 186                 break;
 187         }
 188         return bss_hotplug_slot;
 189 }
 190
 191 static void sn_bus_alloc_data(struct pci_dev *dev)
 192 {
 193         struct list_head *node;
 194         struct pci_bus *subordinate_bus;
 195         struct pci_dev *child;
 196
 197         sn_pci_fixup_slot(dev);
 198
 199         /* Recursively sets up the sn_irq_info structs */
 200         if (dev->subordinate) {
 201                 subordinate_bus = dev->subordinate;
 202                 list_for_each(node, &subordinate_bus->devices) {
 203                         child = list_entry(node, struct pci_dev, bus_list);
 204                         sn_bus_alloc_data(child);
 205                 }
 206         }
 207 }
 208
 209 static void sn_bus_free_data(struct pci_dev *dev)
 210 {
 211         struct list_head *node;
 212         struct pci_bus *subordinate_bus;
 213         struct pci_dev *child;
 214
 215         /* Recursively clean up sn_irq_info structs */
 216         if (dev->subordinate) {
 217                 subordinate_bus = dev->subordinate;
 218                 list_for_each(node, &subordinate_bus->devices) {
 219                         child = list_entry(node, struct pci_dev, bus_list);
 220                         sn_bus_free_data(child);
 221                 }
 222         }
 223         sn_pci_unfixup_slot(dev);
 224 }
 225
 226 static u8 sn_power_status_get(struct hotplug_slot *bss_hotplug_slot)
 227 {
 228         struct slot *slot = (struct slot *)bss_hotplug_slot->private;
 229         struct pcibus_info *pcibus_info;
 230         u8 retval;
 231
 232         pcibus_info = SN_PCIBUS_BUSSOFT_INFO(slot->pci_bus);
 233         retval = pcibus_info->pbi_enabled_devices & (1 << slot->device_num);
 234
 235         return retval ? 1 : 0;
 236 }
 237
 238 static void sn_slot_mark_enable(struct hotplug_slot *bss_hotplug_slot,
 239                                 int device_num)
 240 {
 241         struct slot *slot = (struct slot *)bss_hotplug_slot->private;
 242         struct pcibus_info *pcibus_info;
 243
 244         pcibus_info = SN_PCIBUS_BUSSOFT_INFO(slot->pci_bus);
 245         pcibus_info->pbi_enabled_devices |= (1 << device_num);
 246 }
 247
 248 static void sn_slot_mark_disable(struct hotplug_slot *bss_hotplug_slot,
 249                                  int device_num)
 250 {
 251         struct slot *slot = (struct slot *)bss_hotplug_slot->private;
 252         struct pcibus_info *pcibus_info;
 253
 254         pcibus_info = SN_PCIBUS_BUSSOFT_INFO(slot->pci_bus);
 255         pcibus_info->pbi_enabled_devices &= ~(1 << device_num);
 256 }
 257
 258 static int sn_slot_enable(struct hotplug_slot *bss_hotplug_slot,
 259                           int device_num)
 260 {
 261         struct slot *slot = (struct slot *)bss_hotplug_slot->private;
 262         struct pcibus_info *pcibus_info;
 263         struct pcibr_slot_enable_resp resp;
 264         int rc;
 265
 266         pcibus_info = SN_PCIBUS_BUSSOFT_INFO(slot->pci_bus);
 267
 268         /*
 269          * Power-on and initialize the slot in the SN
 270          * PCI infrastructure.
 271          */
 272         rc = sal_pcibr_slot_enable(pcibus_info, device_num, &resp);
 273
 274         if (rc == PCI_SLOT_ALREADY_UP) {
 275                 dev_dbg(slot->pci_bus->self, "is already active\n");
 276                 return -EPERM;
 277         }
 278
 279         if (rc == PCI_L1_ERR) {
 280                 dev_dbg(slot->pci_bus->self,
 281                         "L1 failure %d with message: %s",
 282                         resp.resp_sub_errno, resp.resp_l1_msg);
 283                 return -EPERM;
 284         }
 285
 286         if (rc) {
 287                 dev_dbg(slot->pci_bus->self,
 288                         "insert failed with error %d sub-error %d\n",
 289                         rc, resp.resp_sub_errno);
 290                 return -EIO;
 291         }
 292
 293         sn_slot_mark_enable(bss_hotplug_slot, device_num);
 294
 295         return 0;
 296 }
 297
 298 static int sn_slot_disable(struct hotplug_slot *bss_hotplug_slot,
 299                            int device_num, int action)
 300 {
 301         struct slot *slot = (struct slot *)bss_hotplug_slot->private;
 302         struct pcibus_info *pcibus_info;
 303         struct pcibr_slot_disable_resp resp;
 304         int rc;
 305
 306         pcibus_info = SN_PCIBUS_BUSSOFT_INFO(slot->pci_bus);
 307
 308         rc = sal_pcibr_slot_disable(pcibus_info, device_num, action, &resp);
 309
 310         if (action == PCI_REQ_SLOT_ELIGIBLE && rc == PCI_SLOT_ALREADY_DOWN) {
 311                 dev_dbg(slot->pci_bus->self, "Slot %s already inactive\n");
 312                 return -ENODEV;
 313         }
 314
 315         if (action == PCI_REQ_SLOT_ELIGIBLE && rc == PCI_EMPTY_33MHZ) {
 316                 dev_dbg(slot->pci_bus->self,
 317                         "Cannot remove last 33MHz card\n");
 318                 return -EPERM;
 319         }
 320
 321         if (action == PCI_REQ_SLOT_ELIGIBLE && rc == PCI_L1_ERR) {
 322                 dev_dbg(slot->pci_bus->self,
 323                         "L1 failure %d with message \n%s\n",
 324                         resp.resp_sub_errno, resp.resp_l1_msg);
 325                 return -EPERM;
 326         }
 327
 328         if (action == PCI_REQ_SLOT_ELIGIBLE && rc) {
 329                 dev_dbg(slot->pci_bus->self,
 330                         "remove failed with error %d sub-error %d\n",
 331                         rc, resp.resp_sub_errno);
 332                 return -EIO;
 333         }
 334
 335         if (action == PCI_REQ_SLOT_ELIGIBLE && !rc)
 336                 return 0;
 337
 338         if (action == PCI_REQ_SLOT_DISABLE && !rc) {
 339                 sn_slot_mark_disable(bss_hotplug_slot, device_num);
 340                 dev_dbg(slot->pci_bus->self, "remove successful\n");
 341                 return 0;
 342         }
 343
 344         if (action == PCI_REQ_SLOT_DISABLE && rc) {
 345                 dev_dbg(slot->pci_bus->self,"remove failed rc = %d\n", rc);
 346                 return rc;
 347         }
 348
 349         return rc;
 350 }
 351
 352 static int enable_slot(struct hotplug_slot *bss_hotplug_slot)
 353 {
 354         struct slot *slot = (struct slot *)bss_hotplug_slot->private;
 355         struct pci_bus *new_bus = NULL;
 356         struct pci_dev *dev;
 357         int func, num_funcs;
 358         int new_ppb = 0;
 359         int rc;
 360
 361         /* Serialize the Linux PCI infrastructure */
 362         down(&sn_hotplug_sem);
 363
 364         /*
 365          * Power-on and initialize the slot in the SN
 366          * PCI infrastructure.
 367          */
 368         rc = sn_slot_enable(bss_hotplug_slot, slot->device_num);
 369         if (rc) {
 370                 up(&sn_hotplug_sem);
 371                 return rc;
 372         }
 373
 374         num_funcs = pci_scan_slot(slot->pci_bus, PCI_DEVFN(slot->device_num+1,
 375                                                            PCI_FUNC(0)));
 376         if (!num_funcs) {
 377                 dev_dbg(slot->pci_bus->self, "no device in slot\n");
 378                 up(&sn_hotplug_sem);
 379                 return -ENODEV;
 380         }
 381
 382         sn_pci_controller_fixup(pci_domain_nr(slot->pci_bus),
 383                                 slot->pci_bus->number,
 384                                 slot->pci_bus);
 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
 395
 396                 if (dev) {
 397                         if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
 398                                 unsigned char sec_bus;
 399                                 pci_read_config_byte(dev, PCI_SECONDARY_BUS,
 400                                                      &sec_bus);
 401                                 new_bus = pci_add_new_bus(dev->bus, dev,
 402                                                           sec_bus);
 403                                 pci_scan_child_bus(new_bus);
 404                                 sn_pci_controller_fixup(pci_domain_nr(new_bus),
 405                                                         new_bus->number,
 406                                                         new_bus);
 407                                 new_ppb = 1;
 408                         }
 409                         sn_bus_alloc_data(dev);
 410                         pci_dev_put(dev);
 411                 }
 412         }
 413
 414         /* Call the driver for the new device */
 415         pci_bus_add_devices(slot->pci_bus);
 416         /* Call the drivers for the new devices subordinate to PPB */
 417         if (new_ppb)
 418                 pci_bus_add_devices(new_bus);
 419
 420         up(&sn_hotplug_sem);
 421
 422         if (rc == 0)
 423                 dev_dbg(slot->pci_bus->self,
 424                         "insert operation successful\n");
 425         else
 426                 dev_dbg(slot->pci_bus->self,
 427                         "insert operation failed rc = %d\n", rc);
 428
 429         return rc;
 430 }
 431
 432 static int disable_slot(struct hotplug_slot *bss_hotplug_slot)
 433 {
 434         struct slot *slot = (struct slot *)bss_hotplug_slot->private;
 435         struct pci_dev *dev;
 436         int func;
 437         int rc;
 438
 439         /* Acquire update access to the bus */
 440         down(&sn_hotplug_sem);
 441
 442         /* is it okay to bring this slot down? */
 443         rc = sn_slot_disable(bss_hotplug_slot, slot->device_num,
 444                              PCI_REQ_SLOT_ELIGIBLE);
 445         if (rc)
 446                 goto leaving;
 447
 448         /* Free the SN resources assigned to the Linux device.*/
 449         for (func = 0; func < 8;  func++) {
 450                 dev = pci_get_slot(slot->pci_bus,
 451                                    PCI_DEVFN(slot->device_num+1,
 452                                              PCI_FUNC(func)));
 453                 if (dev) {
 454                         /*
 455                          * Some drivers may use dma accesses during the
 456                          * driver remove function. We release the sysdata
 457                          * areas after the driver remove functions have
 458                          * been called.
 459                          */
 460                         sn_bus_store_sysdata(dev);
 461                         sn_bus_free_data(dev);
 462                         pci_remove_bus_device(dev);
 463                         pci_dev_put(dev);
 464                 }
 465         }
 466
 467         /* free the collected sysdata pointers */
 468         sn_bus_free_sysdata();
 469
 470         /* Deactivate slot */
 471         rc = sn_slot_disable(bss_hotplug_slot, slot->device_num,
 472                              PCI_REQ_SLOT_DISABLE);
 473  leaving:
 474         /* Release the bus lock */
 475         up(&sn_hotplug_sem);
 476
 477         return rc;
 478 }
 479
 480 static int get_power_status(struct hotplug_slot *bss_hotplug_slot, u8 *value)
 481 {
 482         down(&sn_hotplug_sem);
 483         *value = sn_power_status_get(bss_hotplug_slot);
 484         up(&sn_hotplug_sem);
 485         return 0;
 486 }
 487
 488 static void sn_release_slot(struct hotplug_slot *bss_hotplug_slot)
 489 {
 490         kfree(bss_hotplug_slot->info);
 491         kfree(bss_hotplug_slot->name);
 492         kfree(bss_hotplug_slot->private);
 493         kfree(bss_hotplug_slot);
 494 }
 495
 496 static int sn_hotplug_slot_register(struct pci_bus *pci_bus)
 497 {
 498         int device;
 499         struct hotplug_slot *bss_hotplug_slot;
 500         int rc = 0;
 501
 502         /*
 503          * Currently only four devices are supported,
 504          * in the future there maybe more -- up to 32.
 505          */
 506
 507         for (device = 0; device < SN_MAX_HP_SLOTS ; device++) {
 508                 if (sn_pci_slot_valid(pci_bus, device) != 1)
 509                         continue;
 510
 511                 bss_hotplug_slot = kcalloc(1,sizeof(struct hotplug_slot),
 512                                            GFP_KERNEL);
 513                 if (!bss_hotplug_slot) {
 514                         rc = -ENOMEM;
 515                         goto alloc_err;
 516                 }
 517
 518                 bss_hotplug_slot->info =
 519                         kcalloc(1,sizeof(struct hotplug_slot_info),
 520                                 GFP_KERNEL);
 521                 if (!bss_hotplug_slot->info) {
 522                         rc = -ENOMEM;
 523                         goto alloc_err;
 524                 }
 525
 526                 if (sn_hp_slot_private_alloc(bss_hotplug_slot,
 527                                              pci_bus, device)) {
 528                         rc = -ENOMEM;
 529                         goto alloc_err;
 530                 }
 531
 532                 bss_hotplug_slot->ops = &sn_hotplug_slot_ops;
 533                 bss_hotplug_slot->release = &sn_release_slot;
 534
 535                 rc = pci_hp_register(bss_hotplug_slot);
 536                 if (rc)
 537                         goto register_err;
 538         }
 539         dev_dbg(pci_bus->self, "Registered bus with hotplug\n");
 540         return rc;
 541
 542 register_err:
 543         dev_dbg(pci_bus->self, "bus failed to register with err = %d\n",
 544                 rc);
 545
 546 alloc_err:
 547         if (rc == -ENOMEM)
 548                 dev_dbg(pci_bus->self, "Memory allocation error\n");
 549
 550         /* destroy THIS element */
 551         if (bss_hotplug_slot)
 552                 sn_release_slot(bss_hotplug_slot);
 553
 554         /* destroy anything else on the list */
 555         while ((bss_hotplug_slot = sn_hp_destroy()))
 556                 pci_hp_deregister(bss_hotplug_slot);
 557
 558         return rc;
 559 }
 560
 561 static int sn_pci_hotplug_init(void)
 562 {
 563         struct pci_bus *pci_bus = NULL;
 564         int rc;
 565         int registered = 0;
 566
 567         INIT_LIST_HEAD(&sn_hp_list);
 568
 569         if (sn_sal_rev() < SGI_HOTPLUG_PROM_REV) {
 570                 printk(KERN_ERR "%s: PROM version must be greater than 4.05\n",
 571                        __FUNCTION__);
 572                 return -EPERM;
 573         }
 574
 575         while ((pci_bus = pci_find_next_bus(pci_bus))) {
 576                 if (!pci_bus->sysdata)
 577                         continue;
 578
 579                 rc = sn_pci_bus_valid(pci_bus);
 580                 if (rc != 1) {
 581                         dev_dbg(pci_bus->self, "not a valid hotplug bus\n");
 582                         continue;
 583                 }
 584                 dev_dbg(pci_bus->self, "valid hotplug bus\n");
 585
 586                 rc = sn_hotplug_slot_register(pci_bus);
 587                 if (!rc)
 588                         registered = 1;
 589                 else {
 590                         registered = 0;
 591                         break;
 592                 }
 593         }
 594
 595         return registered == 1 ? 0 : -ENODEV;
 596 }
 597
 598 static void sn_pci_hotplug_exit(void)
 599 {
 600         struct hotplug_slot *bss_hotplug_slot;
 601
 602         while ((bss_hotplug_slot = sn_hp_destroy())) {
 603                 pci_hp_deregister(bss_hotplug_slot);
 604         }
 605
 606         if (!list_empty(&sn_hp_list))
 607                 printk(KERN_ERR "%s: internal list is not empty\n", __FILE__);
 608 }
 609
 610 module_init(sn_pci_hotplug_init);
 611 module_exit(sn_pci_hotplug_exit);