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/platform_device.h>
  14 #include <linux/slab.h>
  15 #include <linux/module.h>
  16 #include <net/dsa.h>
  17 #include <linux/of.h>
  18 #include <linux/of_mdio.h>
  19 #include <linux/of_platform.h>
  20 #include "dsa_priv.h"
  21
  22 char dsa_driver_version[] = "0.1";
  23
  24
  25 /* switch driver registration ***********************************************/
  26 static DEFINE_MUTEX(dsa_switch_drivers_mutex);
  27 static LIST_HEAD(dsa_switch_drivers);
  28
  29 void register_switch_driver(struct dsa_switch_driver *drv)
  30 {
  31         mutex_lock(&dsa_switch_drivers_mutex);
  32         list_add_tail(&drv->list, &dsa_switch_drivers);
  33         mutex_unlock(&dsa_switch_drivers_mutex);
  34 }
  35 EXPORT_SYMBOL_GPL(register_switch_driver);
  36
  37 void unregister_switch_driver(struct dsa_switch_driver *drv)
  38 {
  39         mutex_lock(&dsa_switch_drivers_mutex);
  40         list_del_init(&drv->list);
  41         mutex_unlock(&dsa_switch_drivers_mutex);
  42 }
  43 EXPORT_SYMBOL_GPL(unregister_switch_driver);
  44
  45 static struct dsa_switch_driver *
  46 dsa_switch_probe(struct device *host_dev, int sw_addr, char **_name)
  47 {
  48         struct dsa_switch_driver *ret;
  49         struct list_head *list;
  50         char *name;
  51
  52         ret = NULL;
  53         name = NULL;
  54
  55         mutex_lock(&dsa_switch_drivers_mutex);
  56         list_for_each(list, &dsa_switch_drivers) {
  57                 struct dsa_switch_driver *drv;
  58
  59                 drv = list_entry(list, struct dsa_switch_driver, list);
  60
  61                 name = drv->probe(host_dev, sw_addr);
  62                 if (name != NULL) {
  63                         ret = drv;
  64                         break;
  65                 }
  66         }
  67         mutex_unlock(&dsa_switch_drivers_mutex);
  68
  69         *_name = name;
  70
  71         return ret;
  72 }
  73
  74
  75 /* basic switch operations **************************************************/
  76 static struct dsa_switch *
  77 dsa_switch_setup(struct dsa_switch_tree *dst, int index,
  78                  struct device *parent, struct device *host_dev)
  79 {
  80         struct dsa_chip_data *pd = dst->pd->chip + index;
  81         struct dsa_switch_driver *drv;
  82         struct dsa_switch *ds;
  83         int ret;
  84         char *name;
  85         int i;
  86         bool valid_name_found = false;
  87
  88         /*
  89          * Probe for switch model.
  90          */
  91         drv = dsa_switch_probe(host_dev, pd->sw_addr, &name);
  92         if (drv == NULL) {
  93                 printk(KERN_ERR "%s[%d]: could not detect attached switch\n",
  94                        dst->master_netdev->name, index);
  95                 return ERR_PTR(-EINVAL);
  96         }
  97         printk(KERN_INFO "%s[%d]: detected a %s switch\n",
  98                 dst->master_netdev->name, index, name);
  99
 100
 101         /*
 102          * Allocate and initialise switch state.
 103          */
 104         ds = kzalloc(sizeof(*ds) + drv->priv_size, GFP_KERNEL);
 105         if (ds == NULL)
 106                 return ERR_PTR(-ENOMEM);
 107
 108         ds->dst = dst;
 109         ds->index = index;
 110         ds->pd = dst->pd->chip + index;
 111         ds->drv = drv;
 112         ds->master_dev = host_dev;
 113
 114         /*
 115          * Validate supplied switch configuration.
 116          */
 117         for (i = 0; i < DSA_MAX_PORTS; i++) {
 118                 char *name;
 119
 120                 name = pd->port_names[i];
 121                 if (name == NULL)
 122                         continue;
 123
 124                 if (!strcmp(name, "cpu")) {
 125                         if (dst->cpu_switch != -1) {
 126                                 printk(KERN_ERR "multiple cpu ports?!\n");
 127                                 ret = -EINVAL;
 128                                 goto out;
 129                         }
 130                         dst->cpu_switch = index;
 131                         dst->cpu_port = i;
 132                 } else if (!strcmp(name, "dsa")) {
 133                         ds->dsa_port_mask |= 1 << i;
 134                 } else {
 135                         ds->phys_port_mask |= 1 << i;
 136                 }
 137                 valid_name_found = true;
 138         }
 139
 140         if (!valid_name_found && i == DSA_MAX_PORTS) {
 141                 ret = -EINVAL;
 142                 goto out;
 143         }
 144
 145         /* Make the built-in MII bus mask match the number of ports,
 146          * switch drivers can override this later
 147          */
 148         ds->phys_mii_mask = ds->phys_port_mask;
 149
 150         /*
 151          * If the CPU connects to this switch, set the switch tree
 152          * tagging protocol to the preferred tagging format of this
 153          * switch.
 154          */
 155         if (dst->cpu_switch == index) {
 156                 switch (drv->tag_protocol) {
 157 #ifdef CONFIG_NET_DSA_TAG_DSA
 158                 case DSA_TAG_PROTO_DSA:
 159                         dst->rcv = dsa_netdev_ops.rcv;
 160                         break;
 161 #endif
 162 #ifdef CONFIG_NET_DSA_TAG_EDSA
 163                 case DSA_TAG_PROTO_EDSA:
 164                         dst->rcv = edsa_netdev_ops.rcv;
 165                         break;
 166 #endif
 167 #ifdef CONFIG_NET_DSA_TAG_TRAILER
 168                 case DSA_TAG_PROTO_TRAILER:
 169                         dst->rcv = trailer_netdev_ops.rcv;
 170                         break;
 171 #endif
 172 #ifdef CONFIG_NET_DSA_TAG_BRCM
 173                 case DSA_TAG_PROTO_BRCM:
 174                         dst->rcv = brcm_netdev_ops.rcv;
 175                         break;
 176 #endif
 177                 default:
 178                         break;
 179                 }
 180
 181                 dst->tag_protocol = drv->tag_protocol;
 182         }
 183
 184         /*
 185          * Do basic register setup.
 186          */
 187         ret = drv->setup(ds);
 188         if (ret < 0)
 189                 goto out;
 190
 191         ret = drv->set_addr(ds, dst->master_netdev->dev_addr);
 192         if (ret < 0)
 193                 goto out;
 194
 195         ds->slave_mii_bus = mdiobus_alloc();
 196         if (ds->slave_mii_bus == NULL) {
 197                 ret = -ENOMEM;
 198                 goto out;
 199         }
 200         dsa_slave_mii_bus_init(ds);
 201
 202         ret = mdiobus_register(ds->slave_mii_bus);
 203         if (ret < 0)
 204                 goto out_free;
 205
 206
 207         /*
 208          * Create network devices for physical switch ports.
 209          */
 210         for (i = 0; i < DSA_MAX_PORTS; i++) {
 211                 struct net_device *slave_dev;
 212
 213                 if (!(ds->phys_port_mask & (1 << i)))
 214                         continue;
 215
 216                 slave_dev = dsa_slave_create(ds, parent, i, pd->port_names[i]);
 217                 if (slave_dev == NULL) {
 218                         printk(KERN_ERR "%s[%d]: can't create dsa "
 219                                "slave device for port %d(%s)\n",
 220                                dst->master_netdev->name,
 221                                index, i, pd->port_names[i]);
 222                         continue;
 223                 }
 224
 225                 ds->ports[i] = slave_dev;
 226         }
 227
 228         return ds;
 229
 230 out_free:
 231         mdiobus_free(ds->slave_mii_bus);
 232 out:
 233         kfree(ds);
 234         return ERR_PTR(ret);
 235 }
 236
 237 static void dsa_switch_destroy(struct dsa_switch *ds)
 238 {
 239 }
 240
 241
 242 /* link polling *************************************************************/
 243 static void dsa_link_poll_work(struct work_struct *ugly)
 244 {
 245         struct dsa_switch_tree *dst;
 246         int i;
 247
 248         dst = container_of(ugly, struct dsa_switch_tree, link_poll_work);
 249
 250         for (i = 0; i < dst->pd->nr_chips; i++) {
 251                 struct dsa_switch *ds = dst->ds[i];
 252
 253                 if (ds != NULL && ds->drv->poll_link != NULL)
 254                         ds->drv->poll_link(ds);
 255         }
 256
 257         mod_timer(&dst->link_poll_timer, round_jiffies(jiffies + HZ));
 258 }
 259
 260 static void dsa_link_poll_timer(unsigned long _dst)
 261 {
 262         struct dsa_switch_tree *dst = (void *)_dst;
 263
 264         schedule_work(&dst->link_poll_work);
 265 }
 266
 267
 268 /* platform driver init and cleanup *****************************************/
 269 static int dev_is_class(struct device *dev, void *class)
 270 {
 271         if (dev->class != NULL && !strcmp(dev->class->name, class))
 272                 return 1;
 273
 274         return 0;
 275 }
 276
 277 static struct device *dev_find_class(struct device *parent, char *class)
 278 {
 279         if (dev_is_class(parent, class)) {
 280                 get_device(parent);
 281                 return parent;
 282         }
 283
 284         return device_find_child(parent, class, dev_is_class);
 285 }
 286
 287 struct mii_bus *dsa_host_dev_to_mii_bus(struct device *dev)
 288 {
 289         struct device *d;
 290
 291         d = dev_find_class(dev, "mdio_bus");
 292         if (d != NULL) {
 293                 struct mii_bus *bus;
 294
 295                 bus = to_mii_bus(d);
 296                 put_device(d);
 297
 298                 return bus;
 299         }
 300
 301         return NULL;
 302 }
 303 EXPORT_SYMBOL_GPL(dsa_host_dev_to_mii_bus);
 304
 305 static struct net_device *dev_to_net_device(struct device *dev)
 306 {
 307         struct device *d;
 308
 309         d = dev_find_class(dev, "net");
 310         if (d != NULL) {
 311                 struct net_device *nd;
 312
 313                 nd = to_net_dev(d);
 314                 dev_hold(nd);
 315                 put_device(d);
 316
 317                 return nd;
 318         }
 319
 320         return NULL;
 321 }
 322
 323 #ifdef CONFIG_OF
 324 static int dsa_of_setup_routing_table(struct dsa_platform_data *pd,
 325                                         struct dsa_chip_data *cd,
 326                                         int chip_index,
 327                                         struct device_node *link)
 328 {
 329         int ret;
 330         const __be32 *reg;
 331         int link_port_addr;
 332         int link_sw_addr;
 333         struct device_node *parent_sw;
 334         int len;
 335
 336         parent_sw = of_get_parent(link);
 337         if (!parent_sw)
 338                 return -EINVAL;
 339
 340         reg = of_get_property(parent_sw, "reg", &len);
 341         if (!reg || (len != sizeof(*reg) * 2))
 342                 return -EINVAL;
 343
 344         link_sw_addr = be32_to_cpup(reg + 1);
 345
 346         if (link_sw_addr >= pd->nr_chips)
 347                 return -EINVAL;
 348
 349         /* First time routing table allocation */
 350         if (!cd->rtable) {
 351                 cd->rtable = kmalloc(pd->nr_chips * sizeof(s8), GFP_KERNEL);
 352                 if (!cd->rtable)
 353                         return -ENOMEM;
 354
 355                 /* default to no valid uplink/downlink */
 356                 memset(cd->rtable, -1, pd->nr_chips * sizeof(s8));
 357         }
 358
 359         reg = of_get_property(link, "reg", NULL);
 360         if (!reg) {
 361                 ret = -EINVAL;
 362                 goto out;
 363         }
 364
 365         link_port_addr = be32_to_cpup(reg);
 366
 367         cd->rtable[link_sw_addr] = link_port_addr;
 368
 369         return 0;
 370 out:
 371         kfree(cd->rtable);
 372         return ret;
 373 }
 374
 375 static void dsa_of_free_platform_data(struct dsa_platform_data *pd)
 376 {
 377         int i;
 378         int port_index;
 379
 380         for (i = 0; i < pd->nr_chips; i++) {
 381                 port_index = 0;
 382                 while (port_index < DSA_MAX_PORTS) {
 383                         kfree(pd->chip[i].port_names[port_index]);
 384                         port_index++;
 385                 }
 386                 kfree(pd->chip[i].rtable);
 387         }
 388         kfree(pd->chip);
 389 }
 390
 391 static int dsa_of_probe(struct platform_device *pdev)
 392 {
 393         struct device_node *np = pdev->dev.of_node;
 394         struct device_node *child, *mdio, *ethernet, *port, *link;
 395         struct mii_bus *mdio_bus;
 396         struct platform_device *ethernet_dev;
 397         struct dsa_platform_data *pd;
 398         struct dsa_chip_data *cd;
 399         const char *port_name;
 400         int chip_index, port_index;
 401         const unsigned int *sw_addr, *port_reg;
 402         int ret;
 403
 404         mdio = of_parse_phandle(np, "dsa,mii-bus", 0);
 405         if (!mdio)
 406                 return -EINVAL;
 407
 408         mdio_bus = of_mdio_find_bus(mdio);
 409         if (!mdio_bus)
 410                 return -EINVAL;
 411
 412         ethernet = of_parse_phandle(np, "dsa,ethernet", 0);
 413         if (!ethernet)
 414                 return -EINVAL;
 415
 416         ethernet_dev = of_find_device_by_node(ethernet);
 417         if (!ethernet_dev)
 418                 return -ENODEV;
 419
 420         pd = kzalloc(sizeof(*pd), GFP_KERNEL);
 421         if (!pd)
 422                 return -ENOMEM;
 423
 424         pdev->dev.platform_data = pd;
 425         pd->netdev = &ethernet_dev->dev;
 426         pd->nr_chips = of_get_child_count(np);
 427         if (pd->nr_chips > DSA_MAX_SWITCHES)
 428                 pd->nr_chips = DSA_MAX_SWITCHES;
 429
 430         pd->chip = kzalloc(pd->nr_chips * sizeof(struct dsa_chip_data),
 431                         GFP_KERNEL);
 432         if (!pd->chip) {
 433                 ret = -ENOMEM;
 434                 goto out_free;
 435         }
 436
 437         chip_index = -1;
 438         for_each_available_child_of_node(np, child) {
 439                 chip_index++;
 440                 cd = &pd->chip[chip_index];
 441
 442                 cd->of_node = child;
 443                 cd->mii_bus = &mdio_bus->dev;
 444
 445                 sw_addr = of_get_property(child, "reg", NULL);
 446                 if (!sw_addr)
 447                         continue;
 448
 449                 cd->sw_addr = be32_to_cpup(sw_addr);
 450                 if (cd->sw_addr > PHY_MAX_ADDR)
 451                         continue;
 452
 453                 for_each_available_child_of_node(child, port) {
 454                         port_reg = of_get_property(port, "reg", NULL);
 455                         if (!port_reg)
 456                                 continue;
 457
 458                         port_index = be32_to_cpup(port_reg);
 459
 460                         port_name = of_get_property(port, "label", NULL);
 461                         if (!port_name)
 462                                 continue;
 463
 464                         cd->port_dn[port_index] = port;
 465
 466                         cd->port_names[port_index] = kstrdup(port_name,
 467                                         GFP_KERNEL);
 468                         if (!cd->port_names[port_index]) {
 469                                 ret = -ENOMEM;
 470                                 goto out_free_chip;
 471                         }
 472
 473                         link = of_parse_phandle(port, "link", 0);
 474
 475                         if (!strcmp(port_name, "dsa") && link &&
 476                                         pd->nr_chips > 1) {
 477                                 ret = dsa_of_setup_routing_table(pd, cd,
 478                                                 chip_index, link);
 479                                 if (ret)
 480                                         goto out_free_chip;
 481                         }
 482
 483                         if (port_index == DSA_MAX_PORTS)
 484                                 break;
 485                 }
 486         }
 487
 488         return 0;
 489
 490 out_free_chip:
 491         dsa_of_free_platform_data(pd);
 492 out_free:
 493         kfree(pd);
 494         pdev->dev.platform_data = NULL;
 495         return ret;
 496 }
 497
 498 static void dsa_of_remove(struct platform_device *pdev)
 499 {
 500         struct dsa_platform_data *pd = pdev->dev.platform_data;
 501
 502         if (!pdev->dev.of_node)
 503                 return;
 504
 505         dsa_of_free_platform_data(pd);
 506         kfree(pd);
 507 }
 508 #else
 509 static inline int dsa_of_probe(struct platform_device *pdev)
 510 {
 511         return 0;
 512 }
 513
 514 static inline void dsa_of_remove(struct platform_device *pdev)
 515 {
 516 }
 517 #endif
 518
 519 static int dsa_probe(struct platform_device *pdev)
 520 {
 521         static int dsa_version_printed;
 522         struct dsa_platform_data *pd = pdev->dev.platform_data;
 523         struct net_device *dev;
 524         struct dsa_switch_tree *dst;
 525         int i, ret;
 526
 527         if (!dsa_version_printed++)
 528                 printk(KERN_NOTICE "Distributed Switch Architecture "
 529                         "driver version %s\n", dsa_driver_version);
 530
 531         if (pdev->dev.of_node) {
 532                 ret = dsa_of_probe(pdev);
 533                 if (ret)
 534                         return ret;
 535
 536                 pd = pdev->dev.platform_data;
 537         }
 538
 539         if (pd == NULL || pd->netdev == NULL)
 540                 return -EINVAL;
 541
 542         dev = dev_to_net_device(pd->netdev);
 543         if (dev == NULL) {
 544                 ret = -EINVAL;
 545                 goto out;
 546         }
 547
 548         if (dev->dsa_ptr != NULL) {
 549                 dev_put(dev);
 550                 ret = -EEXIST;
 551                 goto out;
 552         }
 553
 554         dst = kzalloc(sizeof(*dst), GFP_KERNEL);
 555         if (dst == NULL) {
 556                 dev_put(dev);
 557                 ret = -ENOMEM;
 558                 goto out;
 559         }
 560
 561         platform_set_drvdata(pdev, dst);
 562
 563         dst->pd = pd;
 564         dst->master_netdev = dev;
 565         dst->cpu_switch = -1;
 566         dst->cpu_port = -1;
 567
 568         for (i = 0; i < pd->nr_chips; i++) {
 569                 struct dsa_switch *ds;
 570
 571                 ds = dsa_switch_setup(dst, i, &pdev->dev, pd->chip[i].host_dev);
 572                 if (IS_ERR(ds)) {
 573                         printk(KERN_ERR "%s[%d]: couldn't create dsa switch "
 574                                 "instance (error %ld)\n", dev->name, i,
 575                                 PTR_ERR(ds));
 576                         continue;
 577                 }
 578
 579                 dst->ds[i] = ds;
 580                 if (ds->drv->poll_link != NULL)
 581                         dst->link_poll_needed = 1;
 582         }
 583
 584         /*
 585          * If we use a tagging format that doesn't have an ethertype
 586          * field, make sure that all packets from this point on get
 587          * sent to the tag format's receive function.
 588          */
 589         wmb();
 590         dev->dsa_ptr = (void *)dst;
 591
 592         if (dst->link_poll_needed) {
 593                 INIT_WORK(&dst->link_poll_work, dsa_link_poll_work);
 594                 init_timer(&dst->link_poll_timer);
 595                 dst->link_poll_timer.data = (unsigned long)dst;
 596                 dst->link_poll_timer.function = dsa_link_poll_timer;
 597                 dst->link_poll_timer.expires = round_jiffies(jiffies + HZ);
 598                 add_timer(&dst->link_poll_timer);
 599         }
 600
 601         return 0;
 602
 603 out:
 604         dsa_of_remove(pdev);
 605
 606         return ret;
 607 }
 608
 609 static int dsa_remove(struct platform_device *pdev)
 610 {
 611         struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
 612         int i;
 613
 614         if (dst->link_poll_needed)
 615                 del_timer_sync(&dst->link_poll_timer);
 616
 617         flush_work(&dst->link_poll_work);
 618
 619         for (i = 0; i < dst->pd->nr_chips; i++) {
 620                 struct dsa_switch *ds = dst->ds[i];
 621
 622                 if (ds != NULL)
 623                         dsa_switch_destroy(ds);
 624         }
 625
 626         dsa_of_remove(pdev);
 627
 628         return 0;
 629 }
 630
 631 static void dsa_shutdown(struct platform_device *pdev)
 632 {
 633 }
 634
 635 static int dsa_switch_rcv(struct sk_buff *skb, struct net_device *dev,
 636                           struct packet_type *pt, struct net_device *orig_dev)
 637 {
 638         struct dsa_switch_tree *dst = dev->dsa_ptr;
 639
 640         if (unlikely(dst == NULL)) {
 641                 kfree_skb(skb);
 642                 return 0;
 643         }
 644
 645         return dst->rcv(skb, dev, pt, orig_dev);
 646 }
 647
 648 static struct packet_type dsa_pack_type __read_mostly = {
 649         .type   = cpu_to_be16(ETH_P_XDSA),
 650         .func   = dsa_switch_rcv,
 651 };
 652
 653 static const struct of_device_id dsa_of_match_table[] = {
 654         { .compatible = "brcm,bcm7445-switch-v4.0" },
 655         { .compatible = "marvell,dsa", },
 656         {}
 657 };
 658 MODULE_DEVICE_TABLE(of, dsa_of_match_table);
 659
 660 static struct platform_driver dsa_driver = {
 661         .probe          = dsa_probe,
 662         .remove         = dsa_remove,
 663         .shutdown       = dsa_shutdown,
 664         .driver = {
 665                 .name   = "dsa",
 666                 .owner  = THIS_MODULE,
 667                 .of_match_table = dsa_of_match_table,
 668         },
 669 };
 670
 671 static int __init dsa_init_module(void)
 672 {
 673         int rc;
 674
 675         rc = platform_driver_register(&dsa_driver);
 676         if (rc)
 677                 return rc;
 678
 679         dev_add_pack(&dsa_pack_type);
 680
 681         return 0;
 682 }
 683 module_init(dsa_init_module);
 684
 685 static void __exit dsa_cleanup_module(void)
 686 {
 687         dev_remove_pack(&dsa_pack_type);
 688         platform_driver_unregister(&dsa_driver);
 689 }
 690 module_exit(dsa_cleanup_module);
 691
 692 MODULE_AUTHOR("Lennert Buytenhek <buytenh@wantstofly.org>");
 693 MODULE_DESCRIPTION("Driver for Distributed Switch Architecture switch chips");
 694 MODULE_LICENSE("GPL");
 695 MODULE_ALIAS("platform:dsa");