drivers/net/phy/sfp-bus.c

   1 #include <linux/export.h>
   2 #include <linux/kref.h>
   3 #include <linux/list.h>
   4 #include <linux/mutex.h>
   5 #include <linux/phylink.h>
   6 #include <linux/rtnetlink.h>
   7 #include <linux/slab.h>
   8
   9 #include "sfp.h"
  10
  11 /**
  12  * struct sfp_bus - internal representation of a sfp bus
  13  */
  14 struct sfp_bus {
  15         /* private: */
  16         struct kref kref;
  17         struct list_head node;
  18         struct fwnode_handle *fwnode;
  19
  20         const struct sfp_socket_ops *socket_ops;
  21         struct device *sfp_dev;
  22         struct sfp *sfp;
  23
  24         const struct sfp_upstream_ops *upstream_ops;
  25         void *upstream;
  26         struct net_device *netdev;
  27         struct phy_device *phydev;
  28
  29         bool registered;
  30         bool started;
  31 };
  32
  33 /**
  34  * sfp_parse_port() - Parse the EEPROM base ID, setting the port type
  35  * @bus: a pointer to the &struct sfp_bus structure for the sfp module
  36  * @id: a pointer to the module's &struct sfp_eeprom_id
  37  * @support: optional pointer to an array of unsigned long for the
  38  *   ethtool support mask
  39  *
  40  * Parse the EEPROM identification given in @id, and return one of
  41  * %PORT_TP, %PORT_FIBRE or %PORT_OTHER. If @support is non-%NULL,
  42  * also set the ethtool %ETHTOOL_LINK_MODE_xxx_BIT corresponding with
  43  * the connector type.
  44  *
  45  * If the port type is not known, returns %PORT_OTHER.
  46  */
  47 int sfp_parse_port(struct sfp_bus *bus, const struct sfp_eeprom_id *id,
  48                    unsigned long *support)
  49 {
  50         int port;
  51
  52         /* port is the physical connector, set this from the connector field. */
  53         switch (id->base.connector) {
  54         case SFP_CONNECTOR_SC:
  55         case SFP_CONNECTOR_FIBERJACK:
  56         case SFP_CONNECTOR_LC:
  57         case SFP_CONNECTOR_MT_RJ:
  58         case SFP_CONNECTOR_MU:
  59         case SFP_CONNECTOR_OPTICAL_PIGTAIL:
  60                 port = PORT_FIBRE;
  61                 break;
  62
  63         case SFP_CONNECTOR_RJ45:
  64                 port = PORT_TP;
  65                 break;
  66
  67         case SFP_CONNECTOR_COPPER_PIGTAIL:
  68                 port = PORT_DA;
  69                 break;
  70
  71         case SFP_CONNECTOR_UNSPEC:
  72                 if (id->base.e1000_base_t) {
  73                         port = PORT_TP;
  74                         break;
  75                 }
  76                 /* fallthrough */
  77         case SFP_CONNECTOR_SG: /* guess */
  78         case SFP_CONNECTOR_MPO_1X12:
  79         case SFP_CONNECTOR_MPO_2X16:
  80         case SFP_CONNECTOR_HSSDC_II:
  81         case SFP_CONNECTOR_NOSEPARATE:
  82         case SFP_CONNECTOR_MXC_2X16:
  83                 port = PORT_OTHER;
  84                 break;
  85         default:
  86                 dev_warn(bus->sfp_dev, "SFP: unknown connector id 0x%02x\n",
  87                          id->base.connector);
  88                 port = PORT_OTHER;
  89                 break;
  90         }
  91
  92         if (support) {
  93                 switch (port) {
  94                 case PORT_FIBRE:
  95                         phylink_set(support, FIBRE);
  96                         break;
  97
  98                 case PORT_TP:
  99                         phylink_set(support, TP);
 100                         break;
 101                 }
 102         }
 103
 104         return port;
 105 }
 106 EXPORT_SYMBOL_GPL(sfp_parse_port);
 107
 108 /**
 109  * sfp_parse_interface() - Parse the phy_interface_t
 110  * @bus: a pointer to the &struct sfp_bus structure for the sfp module
 111  * @id: a pointer to the module's &struct sfp_eeprom_id
 112  *
 113  * Derive the phy_interface_t mode for the information found in the
 114  * module's identifying EEPROM. There is no standard or defined way
 115  * to derive this information, so we use some heuristics.
 116  *
 117  * If the encoding is 64b66b, then the module must be >= 10G, so
 118  * return %PHY_INTERFACE_MODE_10GKR.
 119  *
 120  * If it's 8b10b, then it's 1G or slower. If it's definitely a fibre
 121  * module, return %PHY_INTERFACE_MODE_1000BASEX mode, otherwise return
 122  * %PHY_INTERFACE_MODE_SGMII mode.
 123  *
 124  * If the encoding is not known, return %PHY_INTERFACE_MODE_NA.
 125  */
 126 phy_interface_t sfp_parse_interface(struct sfp_bus *bus,
 127                                     const struct sfp_eeprom_id *id)
 128 {
 129         phy_interface_t iface;
 130
 131         /* Setting the serdes link mode is guesswork: there's no field in
 132          * the EEPROM which indicates what mode should be used.
 133          *
 134          * If the module wants 64b66b, then it must be >= 10G.
 135          *
 136          * If it's a gigabit-only fiber module, it probably does not have
 137          * a PHY, so switch to 802.3z negotiation mode. Otherwise, switch
 138          * to SGMII mode (which is required to support non-gigabit speeds).
 139          */
 140         switch (id->base.encoding) {
 141         case SFP_ENCODING_8472_64B66B:
 142                 iface = PHY_INTERFACE_MODE_10GKR;
 143                 break;
 144
 145         case SFP_ENCODING_8B10B:
 146                 if (!id->base.e1000_base_t &&
 147                     !id->base.e100_base_lx &&
 148                     !id->base.e100_base_fx)
 149                         iface = PHY_INTERFACE_MODE_1000BASEX;
 150                 else
 151                         iface = PHY_INTERFACE_MODE_SGMII;
 152                 break;
 153
 154         default:
 155                 if (id->base.e1000_base_cx) {
 156                         iface = PHY_INTERFACE_MODE_1000BASEX;
 157                         break;
 158                 }
 159
 160                 iface = PHY_INTERFACE_MODE_NA;
 161                 dev_err(bus->sfp_dev,
 162                         "SFP module encoding does not support 8b10b nor 64b66b\n");
 163                 break;
 164         }
 165
 166         return iface;
 167 }
 168 EXPORT_SYMBOL_GPL(sfp_parse_interface);
 169
 170 /**
 171  * sfp_parse_support() - Parse the eeprom id for supported link modes
 172  * @bus: a pointer to the &struct sfp_bus structure for the sfp module
 173  * @id: a pointer to the module's &struct sfp_eeprom_id
 174  * @support: pointer to an array of unsigned long for the ethtool support mask
 175  *
 176  * Parse the EEPROM identification information and derive the supported
 177  * ethtool link modes for the module.
 178  */
 179 void sfp_parse_support(struct sfp_bus *bus, const struct sfp_eeprom_id *id,
 180                        unsigned long *support)
 181 {
 182         unsigned int br_min, br_nom, br_max;
 183
 184         phylink_set(support, Autoneg);
 185         phylink_set(support, Pause);
 186         phylink_set(support, Asym_Pause);
 187
 188         /* Decode the bitrate information to MBd */
 189         br_min = br_nom = br_max = 0;
 190         if (id->base.br_nominal) {
 191                 if (id->base.br_nominal != 255) {
 192                         br_nom = id->base.br_nominal * 100;
 193                         br_min = br_nom - id->base.br_nominal * id->ext.br_min;
 194                         br_max = br_nom + id->base.br_nominal * id->ext.br_max;
 195                 } else if (id->ext.br_max) {
 196                         br_nom = 250 * id->ext.br_max;
 197                         br_max = br_nom + br_nom * id->ext.br_min / 100;
 198                         br_min = br_nom - br_nom * id->ext.br_min / 100;
 199                 }
 200         }
 201
 202         /* Set ethtool support from the compliance fields. */
 203         if (id->base.e10g_base_sr)
 204                 phylink_set(support, 10000baseSR_Full);
 205         if (id->base.e10g_base_lr)
 206                 phylink_set(support, 10000baseLR_Full);
 207         if (id->base.e10g_base_lrm)
 208                 phylink_set(support, 10000baseLRM_Full);
 209         if (id->base.e10g_base_er)
 210                 phylink_set(support, 10000baseER_Full);
 211         if (id->base.e1000_base_sx ||
 212             id->base.e1000_base_lx ||
 213             id->base.e1000_base_cx)
 214                 phylink_set(support, 1000baseX_Full);
 215         if (id->base.e1000_base_t) {
 216                 phylink_set(support, 1000baseT_Half);
 217                 phylink_set(support, 1000baseT_Full);
 218         }
 219
 220         /* 1000Base-PX or 1000Base-BX10 */
 221         if ((id->base.e_base_px || id->base.e_base_bx10) &&
 222             br_min <= 1300 && br_max >= 1200)
 223                 phylink_set(support, 1000baseX_Full);
 224
 225         /* For active or passive cables, select the link modes
 226          * based on the bit rates and the cable compliance bytes.
 227          */
 228         if ((id->base.sfp_ct_passive || id->base.sfp_ct_active) && br_nom) {
 229                 /* This may look odd, but some manufacturers use 12000MBd */
 230                 if (br_min <= 12000 && br_max >= 10300)
 231                         phylink_set(support, 10000baseCR_Full);
 232                 if (br_min <= 3200 && br_max >= 3100)
 233                         phylink_set(support, 2500baseX_Full);
 234                 if (br_min <= 1300 && br_max >= 1200)
 235                         phylink_set(support, 1000baseX_Full);
 236         }
 237         if (id->base.sfp_ct_passive) {
 238                 if (id->base.passive.sff8431_app_e)
 239                         phylink_set(support, 10000baseCR_Full);
 240         }
 241         if (id->base.sfp_ct_active) {
 242                 if (id->base.active.sff8431_app_e ||
 243                     id->base.active.sff8431_lim) {
 244                         phylink_set(support, 10000baseCR_Full);
 245                 }
 246         }
 247
 248         switch (id->base.extended_cc) {
 249         case 0x00: /* Unspecified */
 250                 break;
 251         case 0x02: /* 100Gbase-SR4 or 25Gbase-SR */
 252                 phylink_set(support, 100000baseSR4_Full);
 253                 phylink_set(support, 25000baseSR_Full);
 254                 break;
 255         case 0x03: /* 100Gbase-LR4 or 25Gbase-LR */
 256         case 0x04: /* 100Gbase-ER4 or 25Gbase-ER */
 257                 phylink_set(support, 100000baseLR4_ER4_Full);
 258                 break;
 259         case 0x0b: /* 100Gbase-CR4 or 25Gbase-CR CA-L */
 260         case 0x0c: /* 25Gbase-CR CA-S */
 261         case 0x0d: /* 25Gbase-CR CA-N */
 262                 phylink_set(support, 100000baseCR4_Full);
 263                 phylink_set(support, 25000baseCR_Full);
 264                 break;
 265         default:
 266                 dev_warn(bus->sfp_dev,
 267                          "Unknown/unsupported extended compliance code: 0x%02x\n",
 268                          id->base.extended_cc);
 269                 break;
 270         }
 271
 272         /* For fibre channel SFP, derive possible BaseX modes */
 273         if (id->base.fc_speed_100 ||
 274             id->base.fc_speed_200 ||
 275             id->base.fc_speed_400) {
 276                 if (id->base.br_nominal >= 31)
 277                         phylink_set(support, 2500baseX_Full);
 278                 if (id->base.br_nominal >= 12)
 279                         phylink_set(support, 1000baseX_Full);
 280         }
 281 }
 282 EXPORT_SYMBOL_GPL(sfp_parse_support);
 283
 284 static LIST_HEAD(sfp_buses);
 285 static DEFINE_MUTEX(sfp_mutex);
 286
 287 static const struct sfp_upstream_ops *sfp_get_upstream_ops(struct sfp_bus *bus)
 288 {
 289         return bus->registered ? bus->upstream_ops : NULL;
 290 }
 291
 292 static struct sfp_bus *sfp_bus_get(struct fwnode_handle *fwnode)
 293 {
 294         struct sfp_bus *sfp, *new, *found = NULL;
 295
 296         new = kzalloc(sizeof(*new), GFP_KERNEL);
 297
 298         mutex_lock(&sfp_mutex);
 299
 300         list_for_each_entry(sfp, &sfp_buses, node) {
 301                 if (sfp->fwnode == fwnode) {
 302                         kref_get(&sfp->kref);
 303                         found = sfp;
 304                         break;
 305                 }
 306         }
 307
 308         if (!found && new) {
 309                 kref_init(&new->kref);
 310                 new->fwnode = fwnode;
 311                 list_add(&new->node, &sfp_buses);
 312                 found = new;
 313                 new = NULL;
 314         }
 315
 316         mutex_unlock(&sfp_mutex);
 317
 318         kfree(new);
 319
 320         return found;
 321 }
 322
 323 static void sfp_bus_release(struct kref *kref)
 324 {
 325         struct sfp_bus *bus = container_of(kref, struct sfp_bus, kref);
 326
 327         list_del(&bus->node);
 328         mutex_unlock(&sfp_mutex);
 329         kfree(bus);
 330 }
 331
 332 static void sfp_bus_put(struct sfp_bus *bus)
 333 {
 334         kref_put_mutex(&bus->kref, sfp_bus_release, &sfp_mutex);
 335 }
 336
 337 static int sfp_register_bus(struct sfp_bus *bus)
 338 {
 339         const struct sfp_upstream_ops *ops = bus->upstream_ops;
 340         int ret;
 341
 342         if (ops) {
 343                 if (ops->link_down)
 344                         ops->link_down(bus->upstream);
 345                 if (ops->connect_phy && bus->phydev) {
 346                         ret = ops->connect_phy(bus->upstream, bus->phydev);
 347                         if (ret)
 348                                 return ret;
 349                 }
 350         }
 351         if (bus->started)
 352                 bus->socket_ops->start(bus->sfp);
 353         bus->registered = true;
 354         return 0;
 355 }
 356
 357 static void sfp_unregister_bus(struct sfp_bus *bus)
 358 {
 359         const struct sfp_upstream_ops *ops = bus->upstream_ops;
 360
 361         if (bus->registered) {
 362                 if (bus->started)
 363                         bus->socket_ops->stop(bus->sfp);
 364                 if (bus->phydev && ops && ops->disconnect_phy)
 365                         ops->disconnect_phy(bus->upstream);
 366         }
 367         bus->registered = false;
 368 }
 369
 370 /**
 371  * sfp_get_module_info() - Get the ethtool_modinfo for a SFP module
 372  * @bus: a pointer to the &struct sfp_bus structure for the sfp module
 373  * @modinfo: a &struct ethtool_modinfo
 374  *
 375  * Fill in the type and eeprom_len parameters in @modinfo for a module on
 376  * the sfp bus specified by @bus.
 377  *
 378  * Returns 0 on success or a negative errno number.
 379  */
 380 int sfp_get_module_info(struct sfp_bus *bus, struct ethtool_modinfo *modinfo)
 381 {
 382         if (!bus->registered)
 383                 return -ENOIOCTLCMD;
 384         return bus->socket_ops->module_info(bus->sfp, modinfo);
 385 }
 386 EXPORT_SYMBOL_GPL(sfp_get_module_info);
 387
 388 /**
 389  * sfp_get_module_eeprom() - Read the SFP module EEPROM
 390  * @bus: a pointer to the &struct sfp_bus structure for the sfp module
 391  * @ee: a &struct ethtool_eeprom
 392  * @data: buffer to contain the EEPROM data (must be at least @ee->len bytes)
 393  *
 394  * Read the EEPROM as specified by the supplied @ee. See the documentation
 395  * for &struct ethtool_eeprom for the region to be read.
 396  *
 397  * Returns 0 on success or a negative errno number.
 398  */
 399 int sfp_get_module_eeprom(struct sfp_bus *bus, struct ethtool_eeprom *ee,
 400                           u8 *data)
 401 {
 402         if (!bus->registered)
 403                 return -ENOIOCTLCMD;
 404         return bus->socket_ops->module_eeprom(bus->sfp, ee, data);
 405 }
 406 EXPORT_SYMBOL_GPL(sfp_get_module_eeprom);
 407
 408 /**
 409  * sfp_upstream_start() - Inform the SFP that the network device is up
 410  * @bus: a pointer to the &struct sfp_bus structure for the sfp module
 411  *
 412  * Inform the SFP socket that the network device is now up, so that the
 413  * module can be enabled by allowing TX_DISABLE to be deasserted. This
 414  * should be called from the network device driver's &struct net_device_ops
 415  * ndo_open() method.
 416  */
 417 void sfp_upstream_start(struct sfp_bus *bus)
 418 {
 419         if (bus->registered)
 420                 bus->socket_ops->start(bus->sfp);
 421         bus->started = true;
 422 }
 423 EXPORT_SYMBOL_GPL(sfp_upstream_start);
 424
 425 /**
 426  * sfp_upstream_stop() - Inform the SFP that the network device is down
 427  * @bus: a pointer to the &struct sfp_bus structure for the sfp module
 428  *
 429  * Inform the SFP socket that the network device is now up, so that the
 430  * module can be disabled by asserting TX_DISABLE, disabling the laser
 431  * in optical modules. This should be called from the network device
 432  * driver's &struct net_device_ops ndo_stop() method.
 433  */
 434 void sfp_upstream_stop(struct sfp_bus *bus)
 435 {
 436         if (bus->registered)
 437                 bus->socket_ops->stop(bus->sfp);
 438         bus->started = false;
 439 }
 440 EXPORT_SYMBOL_GPL(sfp_upstream_stop);
 441
 442 /**
 443  * sfp_register_upstream() - Register the neighbouring device
 444  * @fwnode: firmware node for the SFP bus
 445  * @ndev: network device associated with the interface
 446  * @upstream: the upstream private data
 447  * @ops: the upstream's &struct sfp_upstream_ops
 448  *
 449  * Register the upstream device (eg, PHY) with the SFP bus. MAC drivers
 450  * should use phylink, which will call this function for them. Returns
 451  * a pointer to the allocated &struct sfp_bus.
 452  *
 453  * On error, returns %NULL.
 454  */
 455 struct sfp_bus *sfp_register_upstream(struct fwnode_handle *fwnode,
 456                                       struct net_device *ndev, void *upstream,
 457                                       const struct sfp_upstream_ops *ops)
 458 {
 459         struct sfp_bus *bus = sfp_bus_get(fwnode);
 460         int ret = 0;
 461
 462         if (bus) {
 463                 rtnl_lock();
 464                 bus->upstream_ops = ops;
 465                 bus->upstream = upstream;
 466                 bus->netdev = ndev;
 467
 468                 if (bus->sfp)
 469                         ret = sfp_register_bus(bus);
 470                 rtnl_unlock();
 471         }
 472
 473         if (ret) {
 474                 sfp_bus_put(bus);
 475                 bus = NULL;
 476         }
 477
 478         return bus;
 479 }
 480 EXPORT_SYMBOL_GPL(sfp_register_upstream);
 481
 482 /**
 483  * sfp_unregister_upstream() - Unregister sfp bus
 484  * @bus: a pointer to the &struct sfp_bus structure for the sfp module
 485  *
 486  * Unregister a previously registered upstream connection for the SFP
 487  * module. @bus is returned from sfp_register_upstream().
 488  */
 489 void sfp_unregister_upstream(struct sfp_bus *bus)
 490 {
 491         rtnl_lock();
 492         if (bus->sfp)
 493                 sfp_unregister_bus(bus);
 494         bus->upstream = NULL;
 495         bus->netdev = NULL;
 496         rtnl_unlock();
 497
 498         sfp_bus_put(bus);
 499 }
 500 EXPORT_SYMBOL_GPL(sfp_unregister_upstream);
 501
 502 /* Socket driver entry points */
 503 int sfp_add_phy(struct sfp_bus *bus, struct phy_device *phydev)
 504 {
 505         const struct sfp_upstream_ops *ops = sfp_get_upstream_ops(bus);
 506         int ret = 0;
 507
 508         if (ops && ops->connect_phy)
 509                 ret = ops->connect_phy(bus->upstream, phydev);
 510
 511         if (ret == 0)
 512                 bus->phydev = phydev;
 513
 514         return ret;
 515 }
 516 EXPORT_SYMBOL_GPL(sfp_add_phy);
 517
 518 void sfp_remove_phy(struct sfp_bus *bus)
 519 {
 520         const struct sfp_upstream_ops *ops = sfp_get_upstream_ops(bus);
 521
 522         if (ops && ops->disconnect_phy)
 523                 ops->disconnect_phy(bus->upstream);
 524         bus->phydev = NULL;
 525 }
 526 EXPORT_SYMBOL_GPL(sfp_remove_phy);
 527
 528 void sfp_link_up(struct sfp_bus *bus)
 529 {
 530         const struct sfp_upstream_ops *ops = sfp_get_upstream_ops(bus);
 531
 532         if (ops && ops->link_up)
 533                 ops->link_up(bus->upstream);
 534 }
 535 EXPORT_SYMBOL_GPL(sfp_link_up);
 536
 537 void sfp_link_down(struct sfp_bus *bus)
 538 {
 539         const struct sfp_upstream_ops *ops = sfp_get_upstream_ops(bus);
 540
 541         if (ops && ops->link_down)
 542                 ops->link_down(bus->upstream);
 543 }
 544 EXPORT_SYMBOL_GPL(sfp_link_down);
 545
 546 int sfp_module_insert(struct sfp_bus *bus, const struct sfp_eeprom_id *id)
 547 {
 548         const struct sfp_upstream_ops *ops = sfp_get_upstream_ops(bus);
 549         int ret = 0;
 550
 551         if (ops && ops->module_insert)
 552                 ret = ops->module_insert(bus->upstream, id);
 553
 554         return ret;
 555 }
 556 EXPORT_SYMBOL_GPL(sfp_module_insert);
 557
 558 void sfp_module_remove(struct sfp_bus *bus)
 559 {
 560         const struct sfp_upstream_ops *ops = sfp_get_upstream_ops(bus);
 561
 562         if (ops && ops->module_remove)
 563                 ops->module_remove(bus->upstream);
 564 }
 565 EXPORT_SYMBOL_GPL(sfp_module_remove);
 566
 567 struct sfp_bus *sfp_register_socket(struct device *dev, struct sfp *sfp,
 568                                     const struct sfp_socket_ops *ops)
 569 {
 570         struct sfp_bus *bus = sfp_bus_get(dev->fwnode);
 571         int ret = 0;
 572
 573         if (bus) {
 574                 rtnl_lock();
 575                 bus->sfp_dev = dev;
 576                 bus->sfp = sfp;
 577                 bus->socket_ops = ops;
 578
 579                 if (bus->netdev)
 580                         ret = sfp_register_bus(bus);
 581                 rtnl_unlock();
 582         }
 583
 584         if (ret) {
 585                 sfp_bus_put(bus);
 586                 bus = NULL;
 587         }
 588
 589         return bus;
 590 }
 591 EXPORT_SYMBOL_GPL(sfp_register_socket);
 592
 593 void sfp_unregister_socket(struct sfp_bus *bus)
 594 {
 595         rtnl_lock();
 596         if (bus->netdev)
 597                 sfp_unregister_bus(bus);
 598         bus->sfp_dev = NULL;
 599         bus->sfp = NULL;
 600         bus->socket_ops = NULL;
 601         rtnl_unlock();
 602
 603         sfp_bus_put(bus);
 604 }
 605 EXPORT_SYMBOL_GPL(sfp_unregister_socket);