root/drivers/rapidio/rio-scan.c

DEFINITIONS

1. rio_destid_alloc
2. rio_destid_reserve
3. rio_destid_free
4. rio_destid_first
5. rio_destid_next
6. rio_get_device_id
7. rio_set_device_id
8. rio_clear_locks
9. rio_enum_host
10. rio_device_has_destid
11. rio_release_dev
12. rio_is_switch
13. rio_setup_device
14. rio_sport_is_active
15. rio_get_host_deviceid_lock
16. rio_enum_peer
17. rio_enum_complete
18. rio_disc_peer
19. rio_mport_is_active
20. rio_scan_release_net
21. rio_scan_release_dev
22. rio_scan_alloc_net
23. rio_update_route_tables
24. rio_init_em
25. rio_enum_mport
26. rio_build_route_tables
27. rio_disc_mport
28. rio_basic_attach

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * RapidIO enumeration and discovery support
   4  *
   5  * Copyright 2005 MontaVista Software, Inc.
   6  * Matt Porter <mporter@kernel.crashing.org>
   7  *
   8  * Copyright 2009 Integrated Device Technology, Inc.
   9  * Alex Bounine <alexandre.bounine@idt.com>
  10  * - Added Port-Write/Error Management initialization and handling
  11  *
  12  * Copyright 2009 Sysgo AG
  13  * Thomas Moll <thomas.moll@sysgo.com>
  14  * - Added Input- Output- enable functionality, to allow full communication
  15  */
  16 
  17 #include <linux/types.h>
  18 #include <linux/kernel.h>
  19 
  20 #include <linux/delay.h>
  21 #include <linux/dma-mapping.h>
  22 #include <linux/init.h>
  23 #include <linux/rio.h>
  24 #include <linux/rio_drv.h>
  25 #include <linux/rio_ids.h>
  26 #include <linux/rio_regs.h>
  27 #include <linux/module.h>
  28 #include <linux/spinlock.h>
  29 #include <linux/timer.h>
  30 #include <linux/sched.h>
  31 #include <linux/jiffies.h>
  32 #include <linux/slab.h>
  33 
  34 #include "rio.h"
  35 
  36 static void rio_init_em(struct rio_dev *rdev);
  37 
  38 struct rio_id_table {
  39         u16 start;      /* logical minimal id */
  40         u32 max;        /* max number of IDs in table */
  41         spinlock_t lock;
  42         unsigned long table[0];
  43 };
  44 
  45 static int next_destid = 0;
  46 static int next_comptag = 1;
  47 
  48 /**
  49  * rio_destid_alloc - Allocate next available destID for given network
  50  * @net: RIO network
  51  *
  52  * Returns next available device destination ID for the specified RIO network.
  53  * Marks allocated ID as one in use.
  54  * Returns RIO_INVALID_DESTID if new destID is not available.
  55  */
  56 static u16 rio_destid_alloc(struct rio_net *net)
  57 {
  58         int destid;
  59         struct rio_id_table *idtab = (struct rio_id_table *)net->enum_data;
  60 
  61         spin_lock(&idtab->lock);
  62         destid = find_first_zero_bit(idtab->table, idtab->max);
  63 
  64         if (destid < idtab->max) {
  65                 set_bit(destid, idtab->table);
  66                 destid += idtab->start;
  67         } else
  68                 destid = RIO_INVALID_DESTID;
  69 
  70         spin_unlock(&idtab->lock);
  71         return (u16)destid;
  72 }
  73 
  74 /**
  75  * rio_destid_reserve - Reserve the specified destID
  76  * @net: RIO network
  77  * @destid: destID to reserve
  78  *
  79  * Tries to reserve the specified destID.
  80  * Returns 0 if successful.
  81  */
  82 static int rio_destid_reserve(struct rio_net *net, u16 destid)
  83 {
  84         int oldbit;
  85         struct rio_id_table *idtab = (struct rio_id_table *)net->enum_data;
  86 
  87         destid -= idtab->start;
  88         spin_lock(&idtab->lock);
  89         oldbit = test_and_set_bit(destid, idtab->table);
  90         spin_unlock(&idtab->lock);
  91         return oldbit;
  92 }
  93 
  94 /**
  95  * rio_destid_free - free a previously allocated destID
  96  * @net: RIO network
  97  * @destid: destID to free
  98  *
  99  * Makes the specified destID available for use.
 100  */
 101 static void rio_destid_free(struct rio_net *net, u16 destid)
 102 {
 103         struct rio_id_table *idtab = (struct rio_id_table *)net->enum_data;
 104 
 105         destid -= idtab->start;
 106         spin_lock(&idtab->lock);
 107         clear_bit(destid, idtab->table);
 108         spin_unlock(&idtab->lock);
 109 }
 110 
 111 /**
 112  * rio_destid_first - return first destID in use
 113  * @net: RIO network
 114  */
 115 static u16 rio_destid_first(struct rio_net *net)
 116 {
 117         int destid;
 118         struct rio_id_table *idtab = (struct rio_id_table *)net->enum_data;
 119 
 120         spin_lock(&idtab->lock);
 121         destid = find_first_bit(idtab->table, idtab->max);
 122         if (destid >= idtab->max)
 123                 destid = RIO_INVALID_DESTID;
 124         else
 125                 destid += idtab->start;
 126         spin_unlock(&idtab->lock);
 127         return (u16)destid;
 128 }
 129 
 130 /**
 131  * rio_destid_next - return next destID in use
 132  * @net: RIO network
 133  * @from: destination ID from which search shall continue
 134  */
 135 static u16 rio_destid_next(struct rio_net *net, u16 from)
 136 {
 137         int destid;
 138         struct rio_id_table *idtab = (struct rio_id_table *)net->enum_data;
 139 
 140         spin_lock(&idtab->lock);
 141         destid = find_next_bit(idtab->table, idtab->max, from);
 142         if (destid >= idtab->max)
 143                 destid = RIO_INVALID_DESTID;
 144         else
 145                 destid += idtab->start;
 146         spin_unlock(&idtab->lock);
 147         return (u16)destid;
 148 }
 149 
 150 /**
 151  * rio_get_device_id - Get the base/extended device id for a device
 152  * @port: RIO master port
 153  * @destid: Destination ID of device
 154  * @hopcount: Hopcount to device
 155  *
 156  * Reads the base/extended device id from a device. Returns the
 157  * 8/16-bit device ID.
 158  */
 159 static u16 rio_get_device_id(struct rio_mport *port, u16 destid, u8 hopcount)
 160 {
 161         u32 result;
 162 
 163         rio_mport_read_config_32(port, destid, hopcount, RIO_DID_CSR, &result);
 164 
 165         return RIO_GET_DID(port->sys_size, result);
 166 }
 167 
 168 /**
 169  * rio_set_device_id - Set the base/extended device id for a device
 170  * @port: RIO master port
 171  * @destid: Destination ID of device
 172  * @hopcount: Hopcount to device
 173  * @did: Device ID value to be written
 174  *
 175  * Writes the base/extended device id from a device.
 176  */
 177 static void rio_set_device_id(struct rio_mport *port, u16 destid, u8 hopcount, u16 did)
 178 {
 179         rio_mport_write_config_32(port, destid, hopcount, RIO_DID_CSR,
 180                                   RIO_SET_DID(port->sys_size, did));
 181 }
 182 
 183 /**
 184  * rio_clear_locks- Release all host locks and signal enumeration complete
 185  * @net: RIO network to run on
 186  *
 187  * Marks the component tag CSR on each device with the enumeration
 188  * complete flag. When complete, it then release the host locks on
 189  * each device. Returns 0 on success or %-EINVAL on failure.
 190  */
 191 static int rio_clear_locks(struct rio_net *net)
 192 {
 193         struct rio_mport *port = net->hport;
 194         struct rio_dev *rdev;
 195         u32 result;
 196         int ret = 0;
 197 
 198         /* Release host device id locks */
 199         rio_local_write_config_32(port, RIO_HOST_DID_LOCK_CSR,
 200                                   port->host_deviceid);
 201         rio_local_read_config_32(port, RIO_HOST_DID_LOCK_CSR, &result);
 202         if ((result & 0xffff) != 0xffff) {
 203                 printk(KERN_INFO
 204                        "RIO: badness when releasing host lock on master port, result %8.8x\n",
 205                        result);
 206                 ret = -EINVAL;
 207         }
 208         list_for_each_entry(rdev, &net->devices, net_list) {
 209                 rio_write_config_32(rdev, RIO_HOST_DID_LOCK_CSR,
 210                                     port->host_deviceid);
 211                 rio_read_config_32(rdev, RIO_HOST_DID_LOCK_CSR, &result);
 212                 if ((result & 0xffff) != 0xffff) {
 213                         printk(KERN_INFO
 214                                "RIO: badness when releasing host lock on vid %4.4x did %4.4x\n",
 215                                rdev->vid, rdev->did);
 216                         ret = -EINVAL;
 217                 }
 218 
 219                 /* Mark device as discovered and enable master */
 220                 rio_read_config_32(rdev,
 221                                    rdev->phys_efptr + RIO_PORT_GEN_CTL_CSR,
 222                                    &result);
 223                 result |= RIO_PORT_GEN_DISCOVERED | RIO_PORT_GEN_MASTER;
 224                 rio_write_config_32(rdev,
 225                                     rdev->phys_efptr + RIO_PORT_GEN_CTL_CSR,
 226                                     result);
 227         }
 228 
 229         return ret;
 230 }
 231 
 232 /**
 233  * rio_enum_host- Set host lock and initialize host destination ID
 234  * @port: Master port to issue transaction
 235  *
 236  * Sets the local host master port lock and destination ID register
 237  * with the host device ID value. The host device ID value is provided
 238  * by the platform. Returns %0 on success or %-1 on failure.
 239  */
 240 static int rio_enum_host(struct rio_mport *port)
 241 {
 242         u32 result;
 243 
 244         /* Set master port host device id lock */
 245         rio_local_write_config_32(port, RIO_HOST_DID_LOCK_CSR,
 246                                   port->host_deviceid);
 247 
 248         rio_local_read_config_32(port, RIO_HOST_DID_LOCK_CSR, &result);
 249         if ((result & 0xffff) != port->host_deviceid)
 250                 return -1;
 251 
 252         /* Set master port destid and init destid ctr */
 253         rio_local_set_device_id(port, port->host_deviceid);
 254         return 0;
 255 }
 256 
 257 /**
 258  * rio_device_has_destid- Test if a device contains a destination ID register
 259  * @port: Master port to issue transaction
 260  * @src_ops: RIO device source operations
 261  * @dst_ops: RIO device destination operations
 262  *
 263  * Checks the provided @src_ops and @dst_ops for the necessary transaction
 264  * capabilities that indicate whether or not a device will implement a
 265  * destination ID register. Returns 1 if true or 0 if false.
 266  */
 267 static int rio_device_has_destid(struct rio_mport *port, int src_ops,
 268                                  int dst_ops)
 269 {
 270         u32 mask = RIO_OPS_READ | RIO_OPS_WRITE | RIO_OPS_ATOMIC_TST_SWP | RIO_OPS_ATOMIC_INC | RIO_OPS_ATOMIC_DEC | RIO_OPS_ATOMIC_SET | RIO_OPS_ATOMIC_CLR;
 271 
 272         return !!((src_ops | dst_ops) & mask);
 273 }
 274 
 275 /**
 276  * rio_release_dev- Frees a RIO device struct
 277  * @dev: LDM device associated with a RIO device struct
 278  *
 279  * Gets the RIO device struct associated a RIO device struct.
 280  * The RIO device struct is freed.
 281  */
 282 static void rio_release_dev(struct device *dev)
 283 {
 284         struct rio_dev *rdev;
 285 
 286         rdev = to_rio_dev(dev);
 287         kfree(rdev);
 288 }
 289 
 290 /**
 291  * rio_is_switch- Tests if a RIO device has switch capabilities
 292  * @rdev: RIO device
 293  *
 294  * Gets the RIO device Processing Element Features register
 295  * contents and tests for switch capabilities. Returns 1 if
 296  * the device is a switch or 0 if it is not a switch.
 297  * The RIO device struct is freed.
 298  */
 299 static int rio_is_switch(struct rio_dev *rdev)
 300 {
 301         if (rdev->pef & RIO_PEF_SWITCH)
 302                 return 1;
 303         return 0;
 304 }
 305 
 306 /**
 307  * rio_setup_device- Allocates and sets up a RIO device
 308  * @net: RIO network
 309  * @port: Master port to send transactions
 310  * @destid: Current destination ID
 311  * @hopcount: Current hopcount
 312  * @do_enum: Enumeration/Discovery mode flag
 313  *
 314  * Allocates a RIO device and configures fields based on configuration
 315  * space contents. If device has a destination ID register, a destination
 316  * ID is either assigned in enumeration mode or read from configuration
 317  * space in discovery mode.  If the device has switch capabilities, then
 318  * a switch is allocated and configured appropriately. Returns a pointer
 319  * to a RIO device on success or NULL on failure.
 320  *
 321  */
 322 static struct rio_dev *rio_setup_device(struct rio_net *net,
 323                                         struct rio_mport *port, u16 destid,
 324                                         u8 hopcount, int do_enum)
 325 {
 326         int ret = 0;
 327         struct rio_dev *rdev;
 328         struct rio_switch *rswitch = NULL;
 329         int result, rdid;
 330         size_t size;
 331         u32 swpinfo = 0;
 332 
 333         size = sizeof(struct rio_dev);
 334         if (rio_mport_read_config_32(port, destid, hopcount,
 335                                      RIO_PEF_CAR, &result))
 336                 return NULL;
 337 
 338         if (result & (RIO_PEF_SWITCH | RIO_PEF_MULTIPORT)) {
 339                 rio_mport_read_config_32(port, destid, hopcount,
 340                                          RIO_SWP_INFO_CAR, &swpinfo);
 341                 if (result & RIO_PEF_SWITCH) {
 342                         size += (RIO_GET_TOTAL_PORTS(swpinfo) *
 343                                 sizeof(rswitch->nextdev[0])) + sizeof(*rswitch);
 344                 }
 345         }
 346 
 347         rdev = kzalloc(size, GFP_KERNEL);
 348         if (!rdev)
 349                 return NULL;
 350 
 351         rdev->net = net;
 352         rdev->pef = result;
 353         rdev->swpinfo = swpinfo;
 354         rio_mport_read_config_32(port, destid, hopcount, RIO_DEV_ID_CAR,
 355                                  &result);
 356         rdev->did = result >> 16;
 357         rdev->vid = result & 0xffff;
 358         rio_mport_read_config_32(port, destid, hopcount, RIO_DEV_INFO_CAR,
 359                                  &rdev->device_rev);
 360         rio_mport_read_config_32(port, destid, hopcount, RIO_ASM_ID_CAR,
 361                                  &result);
 362         rdev->asm_did = result >> 16;
 363         rdev->asm_vid = result & 0xffff;
 364         rio_mport_read_config_32(port, destid, hopcount, RIO_ASM_INFO_CAR,
 365                                  &result);
 366         rdev->asm_rev = result >> 16;
 367         if (rdev->pef & RIO_PEF_EXT_FEATURES) {
 368                 rdev->efptr = result & 0xffff;
 369                 rdev->phys_efptr = rio_mport_get_physefb(port, 0, destid,
 370                                                 hopcount, &rdev->phys_rmap);
 371                 pr_debug("RIO: %s Register Map %d device\n",
 372                          __func__, rdev->phys_rmap);
 373 
 374                 rdev->em_efptr = rio_mport_get_feature(port, 0, destid,
 375                                                 hopcount, RIO_EFB_ERR_MGMNT);
 376                 if (!rdev->em_efptr)
 377                         rdev->em_efptr = rio_mport_get_feature(port, 0, destid,
 378                                                 hopcount, RIO_EFB_ERR_MGMNT_HS);
 379         }
 380 
 381         rio_mport_read_config_32(port, destid, hopcount, RIO_SRC_OPS_CAR,
 382                                  &rdev->src_ops);
 383         rio_mport_read_config_32(port, destid, hopcount, RIO_DST_OPS_CAR,
 384                                  &rdev->dst_ops);
 385 
 386         if (do_enum) {
 387                 /* Assign component tag to device */
 388                 if (next_comptag >= 0x10000) {
 389                         pr_err("RIO: Component Tag Counter Overflow\n");
 390                         goto cleanup;
 391                 }
 392                 rio_mport_write_config_32(port, destid, hopcount,
 393                                           RIO_COMPONENT_TAG_CSR, next_comptag);
 394                 rdev->comp_tag = next_comptag++;
 395                 rdev->do_enum = true;
 396         }  else {
 397                 rio_mport_read_config_32(port, destid, hopcount,
 398                                          RIO_COMPONENT_TAG_CSR,
 399                                          &rdev->comp_tag);
 400         }
 401 
 402         if (rio_device_has_destid(port, rdev->src_ops, rdev->dst_ops)) {
 403                 if (do_enum) {
 404                         rio_set_device_id(port, destid, hopcount, next_destid);
 405                         rdev->destid = next_destid;
 406                         next_destid = rio_destid_alloc(net);
 407                 } else
 408                         rdev->destid = rio_get_device_id(port, destid, hopcount);
 409 
 410                 rdev->hopcount = 0xff;
 411         } else {
 412                 /* Switch device has an associated destID which
 413                  * will be adjusted later
 414                  */
 415                 rdev->destid = destid;
 416                 rdev->hopcount = hopcount;
 417         }
 418 
 419         /* If a PE has both switch and other functions, show it as a switch */
 420         if (rio_is_switch(rdev)) {
 421                 rswitch = rdev->rswitch;
 422                 rswitch->port_ok = 0;
 423                 spin_lock_init(&rswitch->lock);
 424                 rswitch->route_table =
 425                         kzalloc(RIO_MAX_ROUTE_ENTRIES(port->sys_size),
 426                                 GFP_KERNEL);
 427                 if (!rswitch->route_table)
 428                         goto cleanup;
 429                 /* Initialize switch route table */
 430                 for (rdid = 0; rdid < RIO_MAX_ROUTE_ENTRIES(port->sys_size);
 431                                 rdid++)
 432                         rswitch->route_table[rdid] = RIO_INVALID_ROUTE;
 433                 dev_set_name(&rdev->dev, "%02x:s:%04x", rdev->net->id,
 434                              rdev->comp_tag & RIO_CTAG_UDEVID);
 435 
 436                 if (do_enum)
 437                         rio_route_clr_table(rdev, RIO_GLOBAL_TABLE, 0);
 438         } else {
 439                 if (do_enum)
 440                         /*Enable Input Output Port (transmitter receiver)*/
 441                         rio_enable_rx_tx_port(port, 0, destid, hopcount, 0);
 442 
 443                 dev_set_name(&rdev->dev, "%02x:e:%04x", rdev->net->id,
 444                              rdev->comp_tag & RIO_CTAG_UDEVID);
 445         }
 446 
 447         rdev->dev.parent = &net->dev;
 448         rio_attach_device(rdev);
 449         rdev->dev.release = rio_release_dev;
 450         rdev->dma_mask = DMA_BIT_MASK(32);
 451         rdev->dev.dma_mask = &rdev->dma_mask;
 452         rdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
 453 
 454         if (rdev->dst_ops & RIO_DST_OPS_DOORBELL)
 455                 rio_init_dbell_res(&rdev->riores[RIO_DOORBELL_RESOURCE],
 456                                    0, 0xffff);
 457 
 458         ret = rio_add_device(rdev);
 459         if (ret)
 460                 goto cleanup;
 461 
 462         rio_dev_get(rdev);
 463 
 464         return rdev;
 465 
 466 cleanup:
 467         if (rswitch)
 468                 kfree(rswitch->route_table);
 469 
 470         kfree(rdev);
 471         return NULL;
 472 }
 473 
 474 /**
 475  * rio_sport_is_active- Tests if a switch port has an active connection.
 476  * @rdev: RapidIO device object
 477  * @sp: Switch port number
 478  *
 479  * Reads the port error status CSR for a particular switch port to
 480  * determine if the port has an active link.  Returns
 481  * %RIO_PORT_N_ERR_STS_PORT_OK if the port is active or %0 if it is
 482  * inactive.
 483  */
 484 static int
 485 rio_sport_is_active(struct rio_dev *rdev, int sp)
 486 {
 487         u32 result = 0;
 488 
 489         rio_read_config_32(rdev, RIO_DEV_PORT_N_ERR_STS_CSR(rdev, sp),
 490                            &result);
 491 
 492         return result & RIO_PORT_N_ERR_STS_PORT_OK;
 493 }
 494 
 495 /**
 496  * rio_get_host_deviceid_lock- Reads the Host Device ID Lock CSR on a device
 497  * @port: Master port to send transaction
 498  * @hopcount: Number of hops to the device
 499  *
 500  * Used during enumeration to read the Host Device ID Lock CSR on a
 501  * RIO device. Returns the value of the lock register.
 502  */
 503 static u16 rio_get_host_deviceid_lock(struct rio_mport *port, u8 hopcount)
 504 {
 505         u32 result;
 506 
 507         rio_mport_read_config_32(port, RIO_ANY_DESTID(port->sys_size), hopcount,
 508                                  RIO_HOST_DID_LOCK_CSR, &result);
 509 
 510         return (u16) (result & 0xffff);
 511 }
 512 
 513 /**
 514  * rio_enum_peer- Recursively enumerate a RIO network through a master port
 515  * @net: RIO network being enumerated
 516  * @port: Master port to send transactions
 517  * @hopcount: Number of hops into the network
 518  * @prev: Previous RIO device connected to the enumerated one
 519  * @prev_port: Port on previous RIO device
 520  *
 521  * Recursively enumerates a RIO network.  Transactions are sent via the
 522  * master port passed in @port.
 523  */
 524 static int rio_enum_peer(struct rio_net *net, struct rio_mport *port,
 525                          u8 hopcount, struct rio_dev *prev, int prev_port)
 526 {
 527         struct rio_dev *rdev;
 528         u32 regval;
 529         int tmp;
 530 
 531         if (rio_mport_chk_dev_access(port,
 532                         RIO_ANY_DESTID(port->sys_size), hopcount)) {
 533                 pr_debug("RIO: device access check failed\n");
 534                 return -1;
 535         }
 536 
 537         if (rio_get_host_deviceid_lock(port, hopcount) == port->host_deviceid) {
 538                 pr_debug("RIO: PE already discovered by this host\n");
 539                 /*
 540                  * Already discovered by this host. Add it as another
 541                  * link to the existing device.
 542                  */
 543                 rio_mport_read_config_32(port, RIO_ANY_DESTID(port->sys_size),
 544                                 hopcount, RIO_COMPONENT_TAG_CSR, &regval);
 545 
 546                 if (regval) {
 547                         rdev = rio_get_comptag((regval & 0xffff), NULL);
 548 
 549                         if (rdev && prev && rio_is_switch(prev)) {
 550                                 pr_debug("RIO: redundant path to %s\n",
 551                                          rio_name(rdev));
 552                                 prev->rswitch->nextdev[prev_port] = rdev;
 553                         }
 554                 }
 555 
 556                 return 0;
 557         }
 558 
 559         /* Attempt to acquire device lock */
 560         rio_mport_write_config_32(port, RIO_ANY_DESTID(port->sys_size),
 561                                   hopcount,
 562                                   RIO_HOST_DID_LOCK_CSR, port->host_deviceid);
 563         while ((tmp = rio_get_host_deviceid_lock(port, hopcount))
 564                < port->host_deviceid) {
 565                 /* Delay a bit */
 566                 mdelay(1);
 567                 /* Attempt to acquire device lock again */
 568                 rio_mport_write_config_32(port, RIO_ANY_DESTID(port->sys_size),
 569                                           hopcount,
 570                                           RIO_HOST_DID_LOCK_CSR,
 571                                           port->host_deviceid);
 572         }
 573 
 574         if (rio_get_host_deviceid_lock(port, hopcount) > port->host_deviceid) {
 575                 pr_debug(
 576                     "RIO: PE locked by a higher priority host...retreating\n");
 577                 return -1;
 578         }
 579 
 580         /* Setup new RIO device */
 581         rdev = rio_setup_device(net, port, RIO_ANY_DESTID(port->sys_size),
 582                                         hopcount, 1);
 583         if (rdev) {
 584                 rdev->prev = prev;
 585                 if (prev && rio_is_switch(prev))
 586                         prev->rswitch->nextdev[prev_port] = rdev;
 587         } else
 588                 return -1;
 589 
 590         if (rio_is_switch(rdev)) {
 591                 int sw_destid;
 592                 int cur_destid;
 593                 int sw_inport;
 594                 u16 destid;
 595                 int port_num;
 596 
 597                 sw_inport = RIO_GET_PORT_NUM(rdev->swpinfo);
 598                 rio_route_add_entry(rdev, RIO_GLOBAL_TABLE,
 599                                     port->host_deviceid, sw_inport, 0);
 600                 rdev->rswitch->route_table[port->host_deviceid] = sw_inport;
 601 
 602                 destid = rio_destid_first(net);
 603                 while (destid != RIO_INVALID_DESTID && destid < next_destid) {
 604                         if (destid != port->host_deviceid) {
 605                                 rio_route_add_entry(rdev, RIO_GLOBAL_TABLE,
 606                                                     destid, sw_inport, 0);
 607                                 rdev->rswitch->route_table[destid] = sw_inport;
 608                         }
 609                         destid = rio_destid_next(net, destid + 1);
 610                 }
 611                 pr_debug(
 612                     "RIO: found %s (vid %4.4x did %4.4x) with %d ports\n",
 613                     rio_name(rdev), rdev->vid, rdev->did,
 614                     RIO_GET_TOTAL_PORTS(rdev->swpinfo));
 615                 sw_destid = next_destid;
 616                 for (port_num = 0;
 617                      port_num < RIO_GET_TOTAL_PORTS(rdev->swpinfo);
 618                      port_num++) {
 619                         if (sw_inport == port_num) {
 620                                 rio_enable_rx_tx_port(port, 0,
 621                                               RIO_ANY_DESTID(port->sys_size),
 622                                               hopcount, port_num);
 623                                 rdev->rswitch->port_ok |= (1 << port_num);
 624                                 continue;
 625                         }
 626 
 627                         cur_destid = next_destid;
 628 
 629                         if (rio_sport_is_active(rdev, port_num)) {
 630                                 pr_debug(
 631                                     "RIO: scanning device on port %d\n",
 632                                     port_num);
 633                                 rio_enable_rx_tx_port(port, 0,
 634                                               RIO_ANY_DESTID(port->sys_size),
 635                                               hopcount, port_num);
 636                                 rdev->rswitch->port_ok |= (1 << port_num);
 637                                 rio_route_add_entry(rdev, RIO_GLOBAL_TABLE,
 638                                                 RIO_ANY_DESTID(port->sys_size),
 639                                                 port_num, 0);
 640 
 641                                 if (rio_enum_peer(net, port, hopcount + 1,
 642                                                   rdev, port_num) < 0)
 643                                         return -1;
 644 
 645                                 /* Update routing tables */
 646                                 destid = rio_destid_next(net, cur_destid + 1);
 647                                 if (destid != RIO_INVALID_DESTID) {
 648                                         for (destid = cur_destid;
 649                                              destid < next_destid;) {
 650                                                 if (destid != port->host_deviceid) {
 651                                                         rio_route_add_entry(rdev,
 652                                                                     RIO_GLOBAL_TABLE,
 653                                                                     destid,
 654                                                                     port_num,
 655                                                                     0);
 656                                                         rdev->rswitch->
 657                                                                 route_table[destid] =
 658                                                                 port_num;
 659                                                 }
 660                                                 destid = rio_destid_next(net,
 661                                                                 destid + 1);
 662                                         }
 663                                 }
 664                         } else {
 665                                 /* If switch supports Error Management,
 666                                  * set PORT_LOCKOUT bit for unused port
 667                                  */
 668                                 if (rdev->em_efptr)
 669                                         rio_set_port_lockout(rdev, port_num, 1);
 670 
 671                                 rdev->rswitch->port_ok &= ~(1 << port_num);
 672                         }
 673                 }
 674 
 675                 /* Direct Port-write messages to the enumeratiing host */
 676                 if ((rdev->src_ops & RIO_SRC_OPS_PORT_WRITE) &&
 677                     (rdev->em_efptr)) {
 678                         rio_write_config_32(rdev,
 679                                         rdev->em_efptr + RIO_EM_PW_TGT_DEVID,
 680                                         (port->host_deviceid << 16) |
 681                                         (port->sys_size << 15));
 682                 }
 683 
 684                 rio_init_em(rdev);
 685 
 686                 /* Check for empty switch */
 687                 if (next_destid == sw_destid)
 688                         next_destid = rio_destid_alloc(net);
 689 
 690                 rdev->destid = sw_destid;
 691         } else
 692                 pr_debug("RIO: found %s (vid %4.4x did %4.4x)\n",
 693                     rio_name(rdev), rdev->vid, rdev->did);
 694 
 695         return 0;
 696 }
 697 
 698 /**
 699  * rio_enum_complete- Tests if enumeration of a network is complete
 700  * @port: Master port to send transaction
 701  *
 702  * Tests the PGCCSR discovered bit for non-zero value (enumeration
 703  * complete flag). Return %1 if enumeration is complete or %0 if
 704  * enumeration is incomplete.
 705  */
 706 static int rio_enum_complete(struct rio_mport *port)
 707 {
 708         u32 regval;
 709 
 710         rio_local_read_config_32(port, port->phys_efptr + RIO_PORT_GEN_CTL_CSR,
 711                                  &regval);
 712         return (regval & RIO_PORT_GEN_DISCOVERED) ? 1 : 0;
 713 }
 714 
 715 /**
 716  * rio_disc_peer- Recursively discovers a RIO network through a master port
 717  * @net: RIO network being discovered
 718  * @port: Master port to send transactions
 719  * @destid: Current destination ID in network
 720  * @hopcount: Number of hops into the network
 721  * @prev: previous rio_dev
 722  * @prev_port: previous port number
 723  *
 724  * Recursively discovers a RIO network.  Transactions are sent via the
 725  * master port passed in @port.
 726  */
 727 static int
 728 rio_disc_peer(struct rio_net *net, struct rio_mport *port, u16 destid,
 729               u8 hopcount, struct rio_dev *prev, int prev_port)
 730 {
 731         u8 port_num, route_port;
 732         struct rio_dev *rdev;
 733         u16 ndestid;
 734 
 735         /* Setup new RIO device */
 736         if ((rdev = rio_setup_device(net, port, destid, hopcount, 0))) {
 737                 rdev->prev = prev;
 738                 if (prev && rio_is_switch(prev))
 739                         prev->rswitch->nextdev[prev_port] = rdev;
 740         } else
 741                 return -1;
 742 
 743         if (rio_is_switch(rdev)) {
 744                 /* Associated destid is how we accessed this switch */
 745                 rdev->destid = destid;
 746 
 747                 pr_debug(
 748                     "RIO: found %s (vid %4.4x did %4.4x) with %d ports\n",
 749                     rio_name(rdev), rdev->vid, rdev->did,
 750                     RIO_GET_TOTAL_PORTS(rdev->swpinfo));
 751                 for (port_num = 0;
 752                      port_num < RIO_GET_TOTAL_PORTS(rdev->swpinfo);
 753                      port_num++) {
 754                         if (RIO_GET_PORT_NUM(rdev->swpinfo) == port_num)
 755                                 continue;
 756 
 757                         if (rio_sport_is_active(rdev, port_num)) {
 758                                 pr_debug(
 759                                     "RIO: scanning device on port %d\n",
 760                                     port_num);
 761 
 762                                 rio_lock_device(port, destid, hopcount, 1000);
 763 
 764                                 for (ndestid = 0;
 765                                      ndestid < RIO_ANY_DESTID(port->sys_size);
 766                                      ndestid++) {
 767                                         rio_route_get_entry(rdev,
 768                                                             RIO_GLOBAL_TABLE,
 769                                                             ndestid,
 770                                                             &route_port, 0);
 771                                         if (route_port == port_num)
 772                                                 break;
 773                                 }
 774 
 775                                 if (ndestid == RIO_ANY_DESTID(port->sys_size))
 776                                         continue;
 777                                 rio_unlock_device(port, destid, hopcount);
 778                                 if (rio_disc_peer(net, port, ndestid,
 779                                         hopcount + 1, rdev, port_num) < 0)
 780                                         return -1;
 781                         }
 782                 }
 783         } else
 784                 pr_debug("RIO: found %s (vid %4.4x did %4.4x)\n",
 785                     rio_name(rdev), rdev->vid, rdev->did);
 786 
 787         return 0;
 788 }
 789 
 790 /**
 791  * rio_mport_is_active- Tests if master port link is active
 792  * @port: Master port to test
 793  *
 794  * Reads the port error status CSR for the master port to
 795  * determine if the port has an active link.  Returns
 796  * %RIO_PORT_N_ERR_STS_PORT_OK if the  master port is active
 797  * or %0 if it is inactive.
 798  */
 799 static int rio_mport_is_active(struct rio_mport *port)
 800 {
 801         u32 result = 0;
 802 
 803         rio_local_read_config_32(port,
 804                 port->phys_efptr +
 805                         RIO_PORT_N_ERR_STS_CSR(port->index, port->phys_rmap),
 806                 &result);
 807         return result & RIO_PORT_N_ERR_STS_PORT_OK;
 808 }
 809 
 810 static void rio_scan_release_net(struct rio_net *net)
 811 {
 812         pr_debug("RIO-SCAN: %s: net_%d\n", __func__, net->id);
 813         kfree(net->enum_data);
 814 }
 815 
 816 static void rio_scan_release_dev(struct device *dev)
 817 {
 818         struct rio_net *net;
 819 
 820         net = to_rio_net(dev);
 821         pr_debug("RIO-SCAN: %s: net_%d\n", __func__, net->id);
 822         kfree(net);
 823 }
 824 
 825 /*
 826  * rio_scan_alloc_net - Allocate and configure a new RIO network
 827  * @mport: Master port associated with the RIO network
 828  * @do_enum: Enumeration/Discovery mode flag
 829  * @start: logical minimal start id for new net
 830  *
 831  * Allocates a new RIO network structure and initializes enumerator-specific
 832  * part of it (if required).
 833  * Returns a RIO network pointer on success or %NULL on failure.
 834  */
 835 static struct rio_net *rio_scan_alloc_net(struct rio_mport *mport,
 836                                           int do_enum, u16 start)
 837 {
 838         struct rio_net *net;
 839 
 840         net = rio_alloc_net(mport);
 841 
 842         if (net && do_enum) {
 843                 struct rio_id_table *idtab;
 844                 size_t size;
 845 
 846                 size = sizeof(struct rio_id_table) +
 847                                 BITS_TO_LONGS(
 848                                         RIO_MAX_ROUTE_ENTRIES(mport->sys_size)
 849                                         ) * sizeof(long);
 850 
 851                 idtab = kzalloc(size, GFP_KERNEL);
 852 
 853                 if (idtab == NULL) {
 854                         pr_err("RIO: failed to allocate destID table\n");
 855                         rio_free_net(net);
 856                         net = NULL;
 857                 } else {
 858                         net->enum_data = idtab;
 859                         net->release = rio_scan_release_net;
 860                         idtab->start = start;
 861                         idtab->max = RIO_MAX_ROUTE_ENTRIES(mport->sys_size);
 862                         spin_lock_init(&idtab->lock);
 863                 }
 864         }
 865 
 866         if (net) {
 867                 net->id = mport->id;
 868                 net->hport = mport;
 869                 dev_set_name(&net->dev, "rnet_%d", net->id);
 870                 net->dev.parent = &mport->dev;
 871                 net->dev.release = rio_scan_release_dev;
 872                 rio_add_net(net);
 873         }
 874 
 875         return net;
 876 }
 877 
 878 /**
 879  * rio_update_route_tables- Updates route tables in switches
 880  * @net: RIO network to run update on
 881  *
 882  * For each enumerated device, ensure that each switch in a system
 883  * has correct routing entries. Add routes for devices that where
 884  * unknown during the first enumeration pass through the switch.
 885  */
 886 static void rio_update_route_tables(struct rio_net *net)
 887 {
 888         struct rio_dev *rdev, *swrdev;
 889         struct rio_switch *rswitch;
 890         u8 sport;
 891         u16 destid;
 892 
 893         list_for_each_entry(rdev, &net->devices, net_list) {
 894 
 895                 destid = rdev->destid;
 896 
 897                 list_for_each_entry(rswitch, &net->switches, node) {
 898 
 899                         if (rio_is_switch(rdev) && (rdev->rswitch == rswitch))
 900                                 continue;
 901 
 902                         if (RIO_INVALID_ROUTE == rswitch->route_table[destid]) {
 903                                 swrdev = sw_to_rio_dev(rswitch);
 904 
 905                                 /* Skip if destid ends in empty switch*/
 906                                 if (swrdev->destid == destid)
 907                                         continue;
 908 
 909                                 sport = RIO_GET_PORT_NUM(swrdev->swpinfo);
 910 
 911                                 rio_route_add_entry(swrdev, RIO_GLOBAL_TABLE,
 912                                                     destid, sport, 0);
 913                                 rswitch->route_table[destid] = sport;
 914                         }
 915                 }
 916         }
 917 }
 918 
 919 /**
 920  * rio_init_em - Initializes RIO Error Management (for switches)
 921  * @rdev: RIO device
 922  *
 923  * For each enumerated switch, call device-specific error management
 924  * initialization routine (if supplied by the switch driver).
 925  */
 926 static void rio_init_em(struct rio_dev *rdev)
 927 {
 928         if (rio_is_switch(rdev) && (rdev->em_efptr) &&
 929             rdev->rswitch->ops && rdev->rswitch->ops->em_init) {
 930                 rdev->rswitch->ops->em_init(rdev);
 931         }
 932 }
 933 
 934 /**
 935  * rio_enum_mport- Start enumeration through a master port
 936  * @mport: Master port to send transactions
 937  * @flags: Enumeration control flags
 938  *
 939  * Starts the enumeration process. If somebody has enumerated our
 940  * master port device, then give up. If not and we have an active
 941  * link, then start recursive peer enumeration. Returns %0 if
 942  * enumeration succeeds or %-EBUSY if enumeration fails.
 943  */
 944 static int rio_enum_mport(struct rio_mport *mport, u32 flags)
 945 {
 946         struct rio_net *net = NULL;
 947         int rc = 0;
 948 
 949         printk(KERN_INFO "RIO: enumerate master port %d, %s\n", mport->id,
 950                mport->name);
 951 
 952         /*
 953          * To avoid multiple start requests (repeat enumeration is not supported
 954          * by this method) check if enumeration/discovery was performed for this
 955          * mport: if mport was added into the list of mports for a net exit
 956          * with error.
 957          */
 958         if (mport->nnode.next || mport->nnode.prev)
 959                 return -EBUSY;
 960 
 961         /* If somebody else enumerated our master port device, bail. */
 962         if (rio_enum_host(mport) < 0) {
 963                 printk(KERN_INFO
 964                        "RIO: master port %d device has been enumerated by a remote host\n",
 965                        mport->id);
 966                 rc = -EBUSY;
 967                 goto out;
 968         }
 969 
 970         /* If master port has an active link, allocate net and enum peers */
 971         if (rio_mport_is_active(mport)) {
 972                 net = rio_scan_alloc_net(mport, 1, 0);
 973                 if (!net) {
 974                         printk(KERN_ERR "RIO: failed to allocate new net\n");
 975                         rc = -ENOMEM;
 976                         goto out;
 977                 }
 978 
 979                 /* reserve mport destID in new net */
 980                 rio_destid_reserve(net, mport->host_deviceid);
 981 
 982                 /* Enable Input Output Port (transmitter receiver) */
 983                 rio_enable_rx_tx_port(mport, 1, 0, 0, 0);
 984 
 985                 /* Set component tag for host */
 986                 rio_local_write_config_32(mport, RIO_COMPONENT_TAG_CSR,
 987                                           next_comptag++);
 988 
 989                 next_destid = rio_destid_alloc(net);
 990 
 991                 if (rio_enum_peer(net, mport, 0, NULL, 0) < 0) {
 992                         /* A higher priority host won enumeration, bail. */
 993                         printk(KERN_INFO
 994                                "RIO: master port %d device has lost enumeration to a remote host\n",
 995                                mport->id);
 996                         rio_clear_locks(net);
 997                         rc = -EBUSY;
 998                         goto out;
 999                 }
1000                 /* free the last allocated destID (unused) */
1001                 rio_destid_free(net, next_destid);
1002                 rio_update_route_tables(net);
1003                 rio_clear_locks(net);
1004                 rio_pw_enable(mport, 1);
1005         } else {
1006                 printk(KERN_INFO "RIO: master port %d link inactive\n",
1007                        mport->id);
1008                 rc = -EINVAL;
1009         }
1010 
1011       out:
1012         return rc;
1013 }
1014 
1015 /**
1016  * rio_build_route_tables- Generate route tables from switch route entries
1017  * @net: RIO network to run route tables scan on
1018  *
1019  * For each switch device, generate a route table by copying existing
1020  * route entries from the switch.
1021  */
1022 static void rio_build_route_tables(struct rio_net *net)
1023 {
1024         struct rio_switch *rswitch;
1025         struct rio_dev *rdev;
1026         int i;
1027         u8 sport;
1028 
1029         list_for_each_entry(rswitch, &net->switches, node) {
1030                 rdev = sw_to_rio_dev(rswitch);
1031 
1032                 rio_lock_device(net->hport, rdev->destid,
1033                                 rdev->hopcount, 1000);
1034                 for (i = 0;
1035                      i < RIO_MAX_ROUTE_ENTRIES(net->hport->sys_size);
1036                      i++) {
1037                         if (rio_route_get_entry(rdev, RIO_GLOBAL_TABLE,
1038                                                 i, &sport, 0) < 0)
1039                                 continue;
1040                         rswitch->route_table[i] = sport;
1041                 }
1042 
1043                 rio_unlock_device(net->hport, rdev->destid, rdev->hopcount);
1044         }
1045 }
1046 
1047 /**
1048  * rio_disc_mport- Start discovery through a master port
1049  * @mport: Master port to send transactions
1050  * @flags: discovery control flags
1051  *
1052  * Starts the discovery process. If we have an active link,
1053  * then wait for the signal that enumeration is complete (if wait
1054  * is allowed).
1055  * When enumeration completion is signaled, start recursive
1056  * peer discovery. Returns %0 if discovery succeeds or %-EBUSY
1057  * on failure.
1058  */
1059 static int rio_disc_mport(struct rio_mport *mport, u32 flags)
1060 {
1061         struct rio_net *net = NULL;
1062         unsigned long to_end;
1063 
1064         printk(KERN_INFO "RIO: discover master port %d, %s\n", mport->id,
1065                mport->name);
1066 
1067         /* If master port has an active link, allocate net and discover peers */
1068         if (rio_mport_is_active(mport)) {
1069                 if (rio_enum_complete(mport))
1070                         goto enum_done;
1071                 else if (flags & RIO_SCAN_ENUM_NO_WAIT)
1072                         return -EAGAIN;
1073 
1074                 pr_debug("RIO: wait for enumeration to complete...\n");
1075 
1076                 to_end = jiffies + CONFIG_RAPIDIO_DISC_TIMEOUT * HZ;
1077                 while (time_before(jiffies, to_end)) {
1078                         if (rio_enum_complete(mport))
1079                                 goto enum_done;
1080                         msleep(10);
1081                 }
1082 
1083                 pr_debug("RIO: discovery timeout on mport %d %s\n",
1084                          mport->id, mport->name);
1085                 goto bail;
1086 enum_done:
1087                 pr_debug("RIO: ... enumeration done\n");
1088 
1089                 net = rio_scan_alloc_net(mport, 0, 0);
1090                 if (!net) {
1091                         printk(KERN_ERR "RIO: Failed to allocate new net\n");
1092                         goto bail;
1093                 }
1094 
1095                 /* Read DestID assigned by enumerator */
1096                 rio_local_read_config_32(mport, RIO_DID_CSR,
1097                                          &mport->host_deviceid);
1098                 mport->host_deviceid = RIO_GET_DID(mport->sys_size,
1099                                                    mport->host_deviceid);
1100 
1101                 if (rio_disc_peer(net, mport, RIO_ANY_DESTID(mport->sys_size),
1102                                         0, NULL, 0) < 0) {
1103                         printk(KERN_INFO
1104                                "RIO: master port %d device has failed discovery\n",
1105                                mport->id);
1106                         goto bail;
1107                 }
1108 
1109                 rio_build_route_tables(net);
1110         }
1111 
1112         return 0;
1113 bail:
1114         return -EBUSY;
1115 }
1116 
1117 static struct rio_scan rio_scan_ops = {
1118         .owner = THIS_MODULE,
1119         .enumerate = rio_enum_mport,
1120         .discover = rio_disc_mport,
1121 };
1122 
1123 static bool scan;
1124 module_param(scan, bool, 0);
1125 MODULE_PARM_DESC(scan, "Start RapidIO network enumeration/discovery "
1126                         "(default = 0)");
1127 
1128 /**
1129  * rio_basic_attach:
1130  *
1131  * When this enumeration/discovery method is loaded as a module this function
1132  * registers its specific enumeration and discover routines for all available
1133  * RapidIO mport devices. The "scan" command line parameter controls ability of
1134  * the module to start RapidIO enumeration/discovery automatically.
1135  *
1136  * Returns 0 for success or -EIO if unable to register itself.
1137  *
1138  * This enumeration/discovery method cannot be unloaded and therefore does not
1139  * provide a matching cleanup_module routine.
1140  */
1141 
1142 static int __init rio_basic_attach(void)
1143 {
1144         if (rio_register_scan(RIO_MPORT_ANY, &rio_scan_ops))
1145                 return -EIO;
1146         if (scan)
1147                 rio_init_mports();
1148         return 0;
1149 }
1150 
1151 late_initcall(rio_basic_attach);
1152 
1153 MODULE_DESCRIPTION("Basic RapidIO enumeration/discovery");
1154 MODULE_LICENSE("GPL");