net/dsa/dsa.c

   1 /*
   2  * net/dsa/dsa.c - Hardware switch handling
   3  * Copyright (c) 2008-2009 Marvell Semiconductor
   4  * Copyright (c) 2013 Florian Fainelli <florian@openwrt.org>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  */
  11
  12 #include <linux/list.h>
  13 #include <linux/netdevice.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/slab.h>
  16 #include <linux/module.h>
  17 #include <net/dsa.h>
  18 #include <linux/of.h>
  19 #include <linux/of_mdio.h>
  20 #include <linux/of_platform.h>
  21 #include "dsa_priv.h"
  22
  23 char dsa_driver_version[] = "0.1";
  24
  25
  26 /* switch driver registration ***********************************************/
  27 static DEFINE_MUTEX(dsa_switch_drivers_mutex);
  28 static LIST_HEAD(dsa_switch_drivers);
  29
  30 void register_switch_driver(struct dsa_switch_driver *drv)
  31 {
  32         mutex_lock(&dsa_switch_drivers_mutex);
  33         list_add_tail(&drv->list, &dsa_switch_drivers);
  34         mutex_unlock(&dsa_switch_drivers_mutex);
  35 }
  36 EXPORT_SYMBOL_GPL(register_switch_driver);
  37
  38 void unregister_switch_driver(struct dsa_switch_driver *drv)
  39 {
  40         mutex_lock(&dsa_switch_drivers_mutex);
  41         list_del_init(&drv->list);
  42         mutex_unlock(&dsa_switch_drivers_mutex);
  43 }
  44 EXPORT_SYMBOL_GPL(unregister_switch_driver);
  45
  46 static struct dsa_switch_driver *
  47 dsa_switch_probe(struct mii_bus *bus, int sw_addr, char **_name)
  48 {
  49         struct dsa_switch_driver *ret;
  50         struct list_head *list;
  51         char *name;
  52
  53         ret = NULL;
  54         name = NULL;
  55
  56         mutex_lock(&dsa_switch_drivers_mutex);
  57         list_for_each(list, &dsa_switch_drivers) {
  58                 struct dsa_switch_driver *drv;
  59
  60                 drv = list_entry(list, struct dsa_switch_driver, list);
  61
  62                 name = drv->probe(bus, sw_addr);
  63                 if (name != NULL) {
  64                         ret = drv;
  65                         break;
  66                 }
  67         }
  68         mutex_unlock(&dsa_switch_drivers_mutex);
  69
  70         *_name = name;
  71
  72         return ret;
  73 }
  74
  75
  76 /* basic switch operations **************************************************/
  77 static struct dsa_switch *
  78 dsa_switch_setup(struct dsa_switch_tree *dst, int index,
  79                  struct device *parent, struct mii_bus *bus)
  80 {
  81         struct dsa_chip_data *pd = dst->pd->chip + index;
  82         struct dsa_switch_driver *drv;
  83         struct dsa_switch *ds;
  84         int ret;
  85         char *name;
  86         int i;
  87         bool valid_name_found = false;
  88
  89         /*
  90          * Probe for switch model.
  91          */
  92         drv = dsa_switch_probe(bus, pd->sw_addr, &name);
  93         if (drv == NULL) {
  94                 printk(KERN_ERR "%s[%d]: could not detect attached switch\n",
  95                        dst->master_netdev->name, index);
  96                 return ERR_PTR(-EINVAL);
  97         }
  98         printk(KERN_INFO "%s[%d]: detected a %s switch\n",
  99                 dst->master_netdev->name, index, name);
 100
 101
 102         /*
 103          * Allocate and initialise switch state.
 104          */
 105         ds = kzalloc(sizeof(*ds) + drv->priv_size, GFP_KERNEL);
 106         if (ds == NULL)
 107                 return ERR_PTR(-ENOMEM);
 108
 109         ds->dst = dst;
 110         ds->index = index;
 111         ds->pd = dst->pd->chip + index;
 112         ds->drv = drv;
 113         ds->master_mii_bus = bus;
 114
 115
 116         /*
 117          * Validate supplied switch configuration.
 118          */
 119         for (i = 0; i < DSA_MAX_PORTS; i++) {
 120                 char *name;
 121
 122                 name = pd->port_names[i];
 123                 if (name == NULL)
 124                         continue;
 125
 126                 if (!strcmp(name, "cpu")) {
 127                         if (dst->cpu_switch != -1) {
 128                                 printk(KERN_ERR "multiple cpu ports?!\n");
 129                                 ret = -EINVAL;
 130                                 goto out;
 131                         }
 132                         dst->cpu_switch = index;
 133                         dst->cpu_port = i;
 134                 } else if (!strcmp(name, "dsa")) {
 135                         ds->dsa_port_mask |= 1 << i;
 136                 } else {
 137                         ds->phys_port_mask |= 1 << i;
 138                 }
 139                 valid_name_found = true;
 140         }
 141
 142         if (!valid_name_found && i == DSA_MAX_PORTS) {
 143                 ret = -EINVAL;
 144                 goto out;
 145         }
 146
 147         /*
 148          * If the CPU connects to this switch, set the switch tree
 149          * tagging protocol to the preferred tagging format of this
 150          * switch.
 151          */
 152         if (ds->dst->cpu_switch == index)
 153                 ds->dst->tag_protocol = drv->tag_protocol;
 154
 155
 156         /*
 157          * Do basic register setup.
 158          */
 159         ret = drv->setup(ds);
 160         if (ret < 0)
 161                 goto out;
 162
 163         ret = drv->set_addr(ds, dst->master_netdev->dev_addr);
 164         if (ret < 0)
 165                 goto out;
 166
 167         ds->slave_mii_bus = mdiobus_alloc();
 168         if (ds->slave_mii_bus == NULL) {
 169                 ret = -ENOMEM;
 170                 goto out;
 171         }
 172         dsa_slave_mii_bus_init(ds);
 173
 174         ret = mdiobus_register(ds->slave_mii_bus);
 175         if (ret < 0)
 176                 goto out_free;
 177
 178
 179         /*
 180          * Create network devices for physical switch ports.
 181          */
 182         for (i = 0; i < DSA_MAX_PORTS; i++) {
 183                 struct net_device *slave_dev;
 184
 185                 if (!(ds->phys_port_mask & (1 << i)))
 186                         continue;
 187
 188                 slave_dev = dsa_slave_create(ds, parent, i, pd->port_names[i]);
 189                 if (slave_dev == NULL) {
 190                         printk(KERN_ERR "%s[%d]: can't create dsa "
 191                                "slave device for port %d(%s)\n",
 192                                dst->master_netdev->name,
 193                                index, i, pd->port_names[i]);
 194                         continue;
 195                 }
 196
 197                 ds->ports[i] = slave_dev;
 198         }
 199
 200         return ds;
 201
 202 out_free:
 203         mdiobus_free(ds->slave_mii_bus);
 204 out:
 205         kfree(ds);
 206         return ERR_PTR(ret);
 207 }
 208
 209 static void dsa_switch_destroy(struct dsa_switch *ds)
 210 {
 211 }
 212
 213
 214 /* link polling *************************************************************/
 215 static void dsa_link_poll_work(struct work_struct *ugly)
 216 {
 217         struct dsa_switch_tree *dst;
 218         int i;
 219
 220         dst = container_of(ugly, struct dsa_switch_tree, link_poll_work);
 221
 222         for (i = 0; i < dst->pd->nr_chips; i++) {
 223                 struct dsa_switch *ds = dst->ds[i];
 224
 225                 if (ds != NULL && ds->drv->poll_link != NULL)
 226                         ds->drv->poll_link(ds);
 227         }
 228
 229         mod_timer(&dst->link_poll_timer, round_jiffies(jiffies + HZ));
 230 }
 231
 232 static void dsa_link_poll_timer(unsigned long _dst)
 233 {
 234         struct dsa_switch_tree *dst = (void *)_dst;
 235
 236         schedule_work(&dst->link_poll_work);
 237 }
 238
 239
 240 /* platform driver init and cleanup *****************************************/
 241 static int dev_is_class(struct device *dev, void *class)
 242 {
 243         if (dev->class != NULL && !strcmp(dev->class->name, class))
 244                 return 1;
 245
 246         return 0;
 247 }
 248
 249 static struct device *dev_find_class(struct device *parent, char *class)
 250 {
 251         if (dev_is_class(parent, class)) {
 252                 get_device(parent);
 253                 return parent;
 254         }
 255
 256         return device_find_child(parent, class, dev_is_class);
 257 }
 258
 259 static struct mii_bus *dev_to_mii_bus(struct device *dev)
 260 {
 261         struct device *d;
 262
 263         d = dev_find_class(dev, "mdio_bus");
 264         if (d != NULL) {
 265                 struct mii_bus *bus;
 266
 267                 bus = to_mii_bus(d);
 268                 put_device(d);
 269
 270                 return bus;
 271         }
 272
 273         return NULL;
 274 }
 275
 276 static struct net_device *dev_to_net_device(struct device *dev)
 277 {
 278         struct device *d;
 279
 280         d = dev_find_class(dev, "net");
 281         if (d != NULL) {
 282                 struct net_device *nd;
 283
 284                 nd = to_net_dev(d);
 285                 dev_hold(nd);
 286                 put_device(d);
 287
 288                 return nd;
 289         }
 290
 291         return NULL;
 292 }
 293
 294 #ifdef CONFIG_OF
 295 static int dsa_of_setup_routing_table(struct dsa_platform_data *pd,
 296                                         struct dsa_chip_data *cd,
 297                                         int chip_index,
 298                                         struct device_node *link)
 299 {
 300         int ret;
 301         const __be32 *reg;
 302         int link_port_addr;
 303         int link_sw_addr;
 304         struct device_node *parent_sw;
 305         int len;
 306
 307         parent_sw = of_get_parent(link);
 308         if (!parent_sw)
 309                 return -EINVAL;
 310
 311         reg = of_get_property(parent_sw, "reg", &len);
 312         if (!reg || (len != sizeof(*reg) * 2))
 313                 return -EINVAL;
 314
 315         link_sw_addr = be32_to_cpup(reg + 1);
 316
 317         if (link_sw_addr >= pd->nr_chips)
 318                 return -EINVAL;
 319
 320         /* First time routing table allocation */
 321         if (!cd->rtable) {
 322                 cd->rtable = kmalloc(pd->nr_chips * sizeof(s8), GFP_KERNEL);
 323                 if (!cd->rtable)
 324                         return -ENOMEM;
 325
 326                 /* default to no valid uplink/downlink */
 327                 memset(cd->rtable, -1, pd->nr_chips * sizeof(s8));
 328         }
 329
 330         reg = of_get_property(link, "reg", NULL);
 331         if (!reg) {
 332                 ret = -EINVAL;
 333                 goto out;
 334         }
 335
 336         link_port_addr = be32_to_cpup(reg);
 337
 338         cd->rtable[link_sw_addr] = link_port_addr;
 339
 340         return 0;
 341 out:
 342         kfree(cd->rtable);
 343         return ret;
 344 }
 345
 346 static void dsa_of_free_platform_data(struct dsa_platform_data *pd)
 347 {
 348         int i;
 349         int port_index;
 350
 351         for (i = 0; i < pd->nr_chips; i++) {
 352                 port_index = 0;
 353                 while (port_index < DSA_MAX_PORTS) {
 354                         if (pd->chip[i].port_names[port_index])
 355                                 kfree(pd->chip[i].port_names[port_index]);
 356                         port_index++;
 357                 }
 358                 kfree(pd->chip[i].rtable);
 359         }
 360         kfree(pd->chip);
 361 }
 362
 363 static int dsa_of_probe(struct platform_device *pdev)
 364 {
 365         struct device_node *np = pdev->dev.of_node;
 366         struct device_node *child, *mdio, *ethernet, *port, *link;
 367         struct mii_bus *mdio_bus;
 368         struct platform_device *ethernet_dev;
 369         struct dsa_platform_data *pd;
 370         struct dsa_chip_data *cd;
 371         const char *port_name;
 372         int chip_index, port_index;
 373         const unsigned int *sw_addr, *port_reg;
 374         int ret;
 375
 376         mdio = of_parse_phandle(np, "dsa,mii-bus", 0);
 377         if (!mdio)
 378                 return -EINVAL;
 379
 380         mdio_bus = of_mdio_find_bus(mdio);
 381         if (!mdio_bus)
 382                 return -EINVAL;
 383
 384         ethernet = of_parse_phandle(np, "dsa,ethernet", 0);
 385         if (!ethernet)
 386                 return -EINVAL;
 387
 388         ethernet_dev = of_find_device_by_node(ethernet);
 389         if (!ethernet_dev)
 390                 return -ENODEV;
 391
 392         pd = kzalloc(sizeof(*pd), GFP_KERNEL);
 393         if (!pd)
 394                 return -ENOMEM;
 395
 396         pdev->dev.platform_data = pd;
 397         pd->netdev = &ethernet_dev->dev;
 398         pd->nr_chips = of_get_child_count(np);
 399         if (pd->nr_chips > DSA_MAX_SWITCHES)
 400                 pd->nr_chips = DSA_MAX_SWITCHES;
 401
 402         pd->chip = kzalloc(pd->nr_chips * sizeof(struct dsa_chip_data),
 403                         GFP_KERNEL);
 404         if (!pd->chip) {
 405                 ret = -ENOMEM;
 406                 goto out_free;
 407         }
 408
 409         chip_index = 0;
 410         for_each_available_child_of_node(np, child) {
 411                 cd = &pd->chip[chip_index];
 412
 413                 cd->mii_bus = &mdio_bus->dev;
 414
 415                 sw_addr = of_get_property(child, "reg", NULL);
 416                 if (!sw_addr)
 417                         continue;
 418
 419                 cd->sw_addr = be32_to_cpup(sw_addr);
 420                 if (cd->sw_addr > PHY_MAX_ADDR)
 421                         continue;
 422
 423                 for_each_available_child_of_node(child, port) {
 424                         port_reg = of_get_property(port, "reg", NULL);
 425                         if (!port_reg)
 426                                 continue;
 427
 428                         port_index = be32_to_cpup(port_reg);
 429
 430                         port_name = of_get_property(port, "label", NULL);
 431                         if (!port_name)
 432                                 continue;
 433
 434                         cd->port_names[port_index] = kstrdup(port_name,
 435                                         GFP_KERNEL);
 436                         if (!cd->port_names[port_index]) {
 437                                 ret = -ENOMEM;
 438                                 goto out_free_chip;
 439                         }
 440
 441                         link = of_parse_phandle(port, "link", 0);
 442
 443                         if (!strcmp(port_name, "dsa") && link &&
 444                                         pd->nr_chips > 1) {
 445                                 ret = dsa_of_setup_routing_table(pd, cd,
 446                                                 chip_index, link);
 447                                 if (ret)
 448                                         goto out_free_chip;
 449                         }
 450
 451                         if (port_index == DSA_MAX_PORTS)
 452                                 break;
 453                 }
 454         }
 455
 456         return 0;
 457
 458 out_free_chip:
 459         dsa_of_free_platform_data(pd);
 460 out_free:
 461         kfree(pd);
 462         pdev->dev.platform_data = NULL;
 463         return ret;
 464 }
 465
 466 static void dsa_of_remove(struct platform_device *pdev)
 467 {
 468         struct dsa_platform_data *pd = pdev->dev.platform_data;
 469
 470         if (!pdev->dev.of_node)
 471                 return;
 472
 473         dsa_of_free_platform_data(pd);
 474         kfree(pd);
 475 }
 476 #else
 477 static inline int dsa_of_probe(struct platform_device *pdev)
 478 {
 479         return 0;
 480 }
 481
 482 static inline void dsa_of_remove(struct platform_device *pdev)
 483 {
 484 }
 485 #endif
 486
 487 static int dsa_probe(struct platform_device *pdev)
 488 {
 489         static int dsa_version_printed;
 490         struct dsa_platform_data *pd = pdev->dev.platform_data;
 491         struct net_device *dev;
 492         struct dsa_switch_tree *dst;
 493         int i, ret;
 494
 495         if (!dsa_version_printed++)
 496                 printk(KERN_NOTICE "Distributed Switch Architecture "
 497                         "driver version %s\n", dsa_driver_version);
 498
 499         if (pdev->dev.of_node) {
 500                 ret = dsa_of_probe(pdev);
 501                 if (ret)
 502                         return ret;
 503
 504                 pd = pdev->dev.platform_data;
 505         }
 506
 507         if (pd == NULL || pd->netdev == NULL)
 508                 return -EINVAL;
 509
 510         dev = dev_to_net_device(pd->netdev);
 511         if (dev == NULL) {
 512                 ret = -EINVAL;
 513                 goto out;
 514         }
 515
 516         if (dev->dsa_ptr != NULL) {
 517                 dev_put(dev);
 518                 ret = -EEXIST;
 519                 goto out;
 520         }
 521
 522         dst = kzalloc(sizeof(*dst), GFP_KERNEL);
 523         if (dst == NULL) {
 524                 dev_put(dev);
 525                 ret = -ENOMEM;
 526                 goto out;
 527         }
 528
 529         platform_set_drvdata(pdev, dst);
 530
 531         dst->pd = pd;
 532         dst->master_netdev = dev;
 533         dst->cpu_switch = -1;
 534         dst->cpu_port = -1;
 535
 536         for (i = 0; i < pd->nr_chips; i++) {
 537                 struct mii_bus *bus;
 538                 struct dsa_switch *ds;
 539
 540                 bus = dev_to_mii_bus(pd->chip[i].mii_bus);
 541                 if (bus == NULL) {
 542                         printk(KERN_ERR "%s[%d]: no mii bus found for "
 543                                 "dsa switch\n", dev->name, i);
 544                         continue;
 545                 }
 546
 547                 ds = dsa_switch_setup(dst, i, &pdev->dev, bus);
 548                 if (IS_ERR(ds)) {
 549                         printk(KERN_ERR "%s[%d]: couldn't create dsa switch "
 550                                 "instance (error %ld)\n", dev->name, i,
 551                                 PTR_ERR(ds));
 552                         continue;
 553                 }
 554
 555                 dst->ds[i] = ds;
 556                 if (ds->drv->poll_link != NULL)
 557                         dst->link_poll_needed = 1;
 558         }
 559
 560         /*
 561          * If we use a tagging format that doesn't have an ethertype
 562          * field, make sure that all packets from this point on get
 563          * sent to the tag format's receive function.
 564          */
 565         wmb();
 566         dev->dsa_ptr = (void *)dst;
 567
 568         if (dst->link_poll_needed) {
 569                 INIT_WORK(&dst->link_poll_work, dsa_link_poll_work);
 570                 init_timer(&dst->link_poll_timer);
 571                 dst->link_poll_timer.data = (unsigned long)dst;
 572                 dst->link_poll_timer.function = dsa_link_poll_timer;
 573                 dst->link_poll_timer.expires = round_jiffies(jiffies + HZ);
 574                 add_timer(&dst->link_poll_timer);
 575         }
 576
 577         return 0;
 578
 579 out:
 580         dsa_of_remove(pdev);
 581
 582         return ret;
 583 }
 584
 585 static int dsa_remove(struct platform_device *pdev)
 586 {
 587         struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
 588         int i;
 589
 590         if (dst->link_poll_needed)
 591                 del_timer_sync(&dst->link_poll_timer);
 592
 593         flush_work(&dst->link_poll_work);
 594
 595         for (i = 0; i < dst->pd->nr_chips; i++) {
 596                 struct dsa_switch *ds = dst->ds[i];
 597
 598                 if (ds != NULL)
 599                         dsa_switch_destroy(ds);
 600         }
 601
 602         dsa_of_remove(pdev);
 603
 604         return 0;
 605 }
 606
 607 static void dsa_shutdown(struct platform_device *pdev)
 608 {
 609 }
 610
 611 static const struct of_device_id dsa_of_match_table[] = {
 612         { .compatible = "marvell,dsa", },
 613         {}
 614 };
 615 MODULE_DEVICE_TABLE(of, dsa_of_match_table);
 616
 617 static struct platform_driver dsa_driver = {
 618         .probe          = dsa_probe,
 619         .remove         = dsa_remove,
 620         .shutdown       = dsa_shutdown,
 621         .driver = {
 622                 .name   = "dsa",
 623                 .owner  = THIS_MODULE,
 624                 .of_match_table = dsa_of_match_table,
 625         },
 626 };
 627
 628 static int __init dsa_init_module(void)
 629 {
 630         int rc;
 631
 632         rc = platform_driver_register(&dsa_driver);
 633         if (rc)
 634                 return rc;
 635
 636 #ifdef CONFIG_NET_DSA_TAG_DSA
 637         dev_add_pack(&dsa_packet_type);
 638 #endif
 639 #ifdef CONFIG_NET_DSA_TAG_EDSA
 640         dev_add_pack(&edsa_packet_type);
 641 #endif
 642 #ifdef CONFIG_NET_DSA_TAG_TRAILER
 643         dev_add_pack(&trailer_packet_type);
 644 #endif
 645         return 0;
 646 }
 647 module_init(dsa_init_module);
 648
 649 static void __exit dsa_cleanup_module(void)
 650 {
 651 #ifdef CONFIG_NET_DSA_TAG_TRAILER
 652         dev_remove_pack(&trailer_packet_type);
 653 #endif
 654 #ifdef CONFIG_NET_DSA_TAG_EDSA
 655         dev_remove_pack(&edsa_packet_type);
 656 #endif
 657 #ifdef CONFIG_NET_DSA_TAG_DSA
 658         dev_remove_pack(&dsa_packet_type);
 659 #endif
 660         platform_driver_unregister(&dsa_driver);
 661 }
 662 module_exit(dsa_cleanup_module);
 663
 664 MODULE_AUTHOR("Lennert Buytenhek <buytenh@wantstofly.org>");
 665 MODULE_DESCRIPTION("Driver for Distributed Switch Architecture switch chips");
 666 MODULE_LICENSE("GPL");
 667 MODULE_ALIAS("platform:dsa");