net/dsa/dsa2.c

   1 /*
   2  * net/dsa/dsa2.c - Hardware switch handling, binding version 2
   3  * Copyright (c) 2008-2009 Marvell Semiconductor
   4  * Copyright (c) 2013 Florian Fainelli <florian@openwrt.org>
   5  * Copyright (c) 2016 Andrew Lunn <andrew@lunn.ch>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  */
  12
  13 #include <linux/device.h>
  14 #include <linux/err.h>
  15 #include <linux/list.h>
  16 #include <linux/slab.h>
  17 #include <linux/rtnetlink.h>
  18 #include <net/dsa.h>
  19 #include <linux/of.h>
  20 #include <linux/of_net.h>
  21 #include "dsa_priv.h"
  22
  23 static LIST_HEAD(dsa_switch_trees);
  24 static DEFINE_MUTEX(dsa2_mutex);
  25
  26 static struct dsa_switch_tree *dsa_get_dst(u32 tree)
  27 {
  28         struct dsa_switch_tree *dst;
  29
  30         list_for_each_entry(dst, &dsa_switch_trees, list)
  31                 if (dst->tree == tree)
  32                         return dst;
  33         return NULL;
  34 }
  35
  36 static void dsa_free_dst(struct kref *ref)
  37 {
  38         struct dsa_switch_tree *dst = container_of(ref, struct dsa_switch_tree,
  39                                                    refcount);
  40
  41         list_del(&dst->list);
  42         kfree(dst);
  43 }
  44
  45 static void dsa_put_dst(struct dsa_switch_tree *dst)
  46 {
  47         kref_put(&dst->refcount, dsa_free_dst);
  48 }
  49
  50 static struct dsa_switch_tree *dsa_add_dst(u32 tree)
  51 {
  52         struct dsa_switch_tree *dst;
  53
  54         dst = kzalloc(sizeof(*dst), GFP_KERNEL);
  55         if (!dst)
  56                 return NULL;
  57         dst->tree = tree;
  58         dst->cpu_switch = -1;
  59         INIT_LIST_HEAD(&dst->list);
  60         list_add_tail(&dsa_switch_trees, &dst->list);
  61         kref_init(&dst->refcount);
  62
  63         return dst;
  64 }
  65
  66 static void dsa_dst_add_ds(struct dsa_switch_tree *dst,
  67                            struct dsa_switch *ds, u32 index)
  68 {
  69         kref_get(&dst->refcount);
  70         dst->ds[index] = ds;
  71 }
  72
  73 static void dsa_dst_del_ds(struct dsa_switch_tree *dst,
  74                            struct dsa_switch *ds, u32 index)
  75 {
  76         dst->ds[index] = NULL;
  77         kref_put(&dst->refcount, dsa_free_dst);
  78 }
  79
  80 static bool dsa_port_is_dsa(struct device_node *port)
  81 {
  82         const char *name;
  83
  84         name = of_get_property(port, "label", NULL);
  85         if (!name)
  86                 return false;
  87
  88         if (!strcmp(name, "dsa"))
  89                 return true;
  90
  91         return false;
  92 }
  93
  94 static bool dsa_port_is_cpu(struct device_node *port)
  95 {
  96         const char *name;
  97
  98         name = of_get_property(port, "label", NULL);
  99         if (!name)
 100                 return false;
 101
 102         if (!strcmp(name, "cpu"))
 103                 return true;
 104
 105         return false;
 106 }
 107
 108 static bool dsa_ds_find_port(struct dsa_switch *ds,
 109                              struct device_node *port)
 110 {
 111         u32 index;
 112
 113         for (index = 0; index < DSA_MAX_PORTS; index++)
 114                 if (ds->ports[index].dn == port)
 115                         return true;
 116         return false;
 117 }
 118
 119 static struct dsa_switch *dsa_dst_find_port(struct dsa_switch_tree *dst,
 120                                             struct device_node *port)
 121 {
 122         struct dsa_switch *ds;
 123         u32 index;
 124
 125         for (index = 0; index < DSA_MAX_SWITCHES; index++) {
 126                 ds = dst->ds[index];
 127                 if (!ds)
 128                         continue;
 129
 130                 if (dsa_ds_find_port(ds, port))
 131                         return ds;
 132         }
 133
 134         return NULL;
 135 }
 136
 137 static int dsa_port_complete(struct dsa_switch_tree *dst,
 138                              struct dsa_switch *src_ds,
 139                              struct device_node *port,
 140                              u32 src_port)
 141 {
 142         struct device_node *link;
 143         int index;
 144         struct dsa_switch *dst_ds;
 145
 146         for (index = 0;; index++) {
 147                 link = of_parse_phandle(port, "link", index);
 148                 if (!link)
 149                         break;
 150
 151                 dst_ds = dsa_dst_find_port(dst, link);
 152                 of_node_put(link);
 153
 154                 if (!dst_ds)
 155                         return 1;
 156
 157                 src_ds->rtable[dst_ds->index] = src_port;
 158         }
 159
 160         return 0;
 161 }
 162
 163 /* A switch is complete if all the DSA ports phandles point to ports
 164  * known in the tree. A return value of 1 means the tree is not
 165  * complete. This is not an error condition. A value of 0 is
 166  * success.
 167  */
 168 static int dsa_ds_complete(struct dsa_switch_tree *dst, struct dsa_switch *ds)
 169 {
 170         struct device_node *port;
 171         u32 index;
 172         int err;
 173
 174         for (index = 0; index < DSA_MAX_PORTS; index++) {
 175                 port = ds->ports[index].dn;
 176                 if (!port)
 177                         continue;
 178
 179                 if (!dsa_port_is_dsa(port))
 180                         continue;
 181
 182                 err = dsa_port_complete(dst, ds, port, index);
 183                 if (err != 0)
 184                         return err;
 185
 186                 ds->dsa_port_mask |= BIT(index);
 187         }
 188
 189         return 0;
 190 }
 191
 192 /* A tree is complete if all the DSA ports phandles point to ports
 193  * known in the tree. A return value of 1 means the tree is not
 194  * complete. This is not an error condition. A value of 0 is
 195  * success.
 196  */
 197 static int dsa_dst_complete(struct dsa_switch_tree *dst)
 198 {
 199         struct dsa_switch *ds;
 200         u32 index;
 201         int err;
 202
 203         for (index = 0; index < DSA_MAX_SWITCHES; index++) {
 204                 ds = dst->ds[index];
 205                 if (!ds)
 206                         continue;
 207
 208                 err = dsa_ds_complete(dst, ds);
 209                 if (err != 0)
 210                         return err;
 211         }
 212
 213         return 0;
 214 }
 215
 216 static int dsa_dsa_port_apply(struct device_node *port, u32 index,
 217                               struct dsa_switch *ds)
 218 {
 219         int err;
 220
 221         err = dsa_cpu_dsa_setup(ds, ds->dev, port, index);
 222         if (err) {
 223                 dev_warn(ds->dev, "Failed to setup dsa port %d: %d\n",
 224                          index, err);
 225                 return err;
 226         }
 227
 228         return 0;
 229 }
 230
 231 static void dsa_dsa_port_unapply(struct device_node *port, u32 index,
 232                                  struct dsa_switch *ds)
 233 {
 234         dsa_cpu_dsa_destroy(port);
 235 }
 236
 237 static int dsa_cpu_port_apply(struct device_node *port, u32 index,
 238                               struct dsa_switch *ds)
 239 {
 240         int err;
 241
 242         err = dsa_cpu_dsa_setup(ds, ds->dev, port, index);
 243         if (err) {
 244                 dev_warn(ds->dev, "Failed to setup cpu port %d: %d\n",
 245                          index, err);
 246                 return err;
 247         }
 248
 249         ds->cpu_port_mask |= BIT(index);
 250
 251         return 0;
 252 }
 253
 254 static void dsa_cpu_port_unapply(struct device_node *port, u32 index,
 255                                  struct dsa_switch *ds)
 256 {
 257         dsa_cpu_dsa_destroy(port);
 258         ds->cpu_port_mask &= ~BIT(index);
 259
 260 }
 261
 262 static int dsa_user_port_apply(struct device_node *port, u32 index,
 263                                struct dsa_switch *ds)
 264 {
 265         const char *name;
 266         int err;
 267
 268         name = of_get_property(port, "label", NULL);
 269
 270         err = dsa_slave_create(ds, ds->dev, index, name);
 271         if (err) {
 272                 dev_warn(ds->dev, "Failed to create slave %d: %d\n",
 273                          index, err);
 274                 return err;
 275         }
 276
 277         return 0;
 278 }
 279
 280 static void dsa_user_port_unapply(struct device_node *port, u32 index,
 281                                   struct dsa_switch *ds)
 282 {
 283         if (ds->ports[index].netdev) {
 284                 dsa_slave_destroy(ds->ports[index].netdev);
 285                 ds->ports[index].netdev = NULL;
 286                 ds->enabled_port_mask &= ~(1 << index);
 287         }
 288 }
 289
 290 static int dsa_ds_apply(struct dsa_switch_tree *dst, struct dsa_switch *ds)
 291 {
 292         struct device_node *port;
 293         u32 index;
 294         int err;
 295
 296         /* Initialize ds->phys_mii_mask before registering the slave MDIO bus
 297          * driver and before drv->setup() has run, since the switch drivers and
 298          * the slave MDIO bus driver rely on these values for probing PHY
 299          * devices or not
 300          */
 301         ds->phys_mii_mask = ds->enabled_port_mask;
 302
 303         err = ds->drv->setup(ds);
 304         if (err < 0)
 305                 return err;
 306
 307         err = ds->drv->set_addr(ds, dst->master_netdev->dev_addr);
 308         if (err < 0)
 309                 return err;
 310
 311         err = ds->drv->set_addr(ds, dst->master_netdev->dev_addr);
 312         if (err < 0)
 313                 return err;
 314
 315         if (!ds->slave_mii_bus && ds->drv->phy_read) {
 316                 ds->slave_mii_bus = devm_mdiobus_alloc(ds->dev);
 317                 if (!ds->slave_mii_bus)
 318                         return -ENOMEM;
 319
 320                 dsa_slave_mii_bus_init(ds);
 321
 322                 err = mdiobus_register(ds->slave_mii_bus);
 323                 if (err < 0)
 324                         return err;
 325         }
 326
 327         for (index = 0; index < DSA_MAX_PORTS; index++) {
 328                 port = ds->ports[index].dn;
 329                 if (!port)
 330                         continue;
 331
 332                 if (dsa_port_is_dsa(port)) {
 333                         err = dsa_dsa_port_apply(port, index, ds);
 334                         if (err)
 335                                 return err;
 336                         continue;
 337                 }
 338
 339                 if (dsa_port_is_cpu(port)) {
 340                         err = dsa_cpu_port_apply(port, index, ds);
 341                         if (err)
 342                                 return err;
 343                         continue;
 344                 }
 345
 346                 err = dsa_user_port_apply(port, index, ds);
 347                 if (err)
 348                         continue;
 349         }
 350
 351         return 0;
 352 }
 353
 354 static void dsa_ds_unapply(struct dsa_switch_tree *dst, struct dsa_switch *ds)
 355 {
 356         struct device_node *port;
 357         u32 index;
 358
 359         for (index = 0; index < DSA_MAX_PORTS; index++) {
 360                 port = ds->ports[index].dn;
 361                 if (!port)
 362                         continue;
 363
 364                 if (dsa_port_is_dsa(port)) {
 365                         dsa_dsa_port_unapply(port, index, ds);
 366                         continue;
 367                 }
 368
 369                 if (dsa_port_is_cpu(port)) {
 370                         dsa_cpu_port_unapply(port, index, ds);
 371                         continue;
 372                 }
 373
 374                 dsa_user_port_unapply(port, index, ds);
 375         }
 376
 377         if (ds->slave_mii_bus && ds->drv->phy_read)
 378                 mdiobus_unregister(ds->slave_mii_bus);
 379 }
 380
 381 static int dsa_dst_apply(struct dsa_switch_tree *dst)
 382 {
 383         struct dsa_switch *ds;
 384         u32 index;
 385         int err;
 386
 387         for (index = 0; index < DSA_MAX_SWITCHES; index++) {
 388                 ds = dst->ds[index];
 389                 if (!ds)
 390                         continue;
 391
 392                 err = dsa_ds_apply(dst, ds);
 393                 if (err)
 394                         return err;
 395         }
 396
 397         err = dsa_cpu_port_ethtool_setup(dst->ds[0]);
 398         if (err)
 399                 return err;
 400
 401         /* If we use a tagging format that doesn't have an ethertype
 402          * field, make sure that all packets from this point on get
 403          * sent to the tag format's receive function.
 404          */
 405         wmb();
 406         dst->master_netdev->dsa_ptr = (void *)dst;
 407         dst->applied = true;
 408
 409         return 0;
 410 }
 411
 412 static void dsa_dst_unapply(struct dsa_switch_tree *dst)
 413 {
 414         struct dsa_switch *ds;
 415         u32 index;
 416
 417         if (!dst->applied)
 418                 return;
 419
 420         dst->master_netdev->dsa_ptr = NULL;
 421
 422         /* If we used a tagging format that doesn't have an ethertype
 423          * field, make sure that all packets from this point get sent
 424          * without the tag and go through the regular receive path.
 425          */
 426         wmb();
 427
 428         for (index = 0; index < DSA_MAX_SWITCHES; index++) {
 429                 ds = dst->ds[index];
 430                 if (!ds)
 431                         continue;
 432
 433                 dsa_ds_unapply(dst, ds);
 434         }
 435
 436         dsa_cpu_port_ethtool_restore(dst->ds[0]);
 437
 438         pr_info("DSA: tree %d unapplied\n", dst->tree);
 439         dst->applied = false;
 440 }
 441
 442 static int dsa_cpu_parse(struct device_node *port, u32 index,
 443                          struct dsa_switch_tree *dst,
 444                          struct dsa_switch *ds)
 445 {
 446         struct net_device *ethernet_dev;
 447         struct device_node *ethernet;
 448
 449         ethernet = of_parse_phandle(port, "ethernet", 0);
 450         if (!ethernet)
 451                 return -EINVAL;
 452
 453         ethernet_dev = of_find_net_device_by_node(ethernet);
 454         if (!ethernet_dev)
 455                 return -EPROBE_DEFER;
 456
 457         if (!ds->master_netdev)
 458                 ds->master_netdev = ethernet_dev;
 459
 460         if (!dst->master_netdev)
 461                 dst->master_netdev = ethernet_dev;
 462
 463         if (dst->cpu_switch == -1) {
 464                 dst->cpu_switch = ds->index;
 465                 dst->cpu_port = index;
 466         }
 467
 468         dst->tag_ops = dsa_resolve_tag_protocol(ds->drv->tag_protocol);
 469         if (IS_ERR(dst->tag_ops)) {
 470                 dev_warn(ds->dev, "No tagger for this switch\n");
 471                 return PTR_ERR(dst->tag_ops);
 472         }
 473
 474         dst->rcv = dst->tag_ops->rcv;
 475
 476         return 0;
 477 }
 478
 479 static int dsa_ds_parse(struct dsa_switch_tree *dst, struct dsa_switch *ds)
 480 {
 481         struct device_node *port;
 482         u32 index;
 483         int err;
 484
 485         for (index = 0; index < DSA_MAX_PORTS; index++) {
 486                 port = ds->ports[index].dn;
 487                 if (!port)
 488                         continue;
 489
 490                 if (dsa_port_is_cpu(port)) {
 491                         err = dsa_cpu_parse(port, index, dst, ds);
 492                         if (err)
 493                                 return err;
 494                 }
 495         }
 496
 497         pr_info("DSA: switch %d %d parsed\n", dst->tree, ds->index);
 498
 499         return 0;
 500 }
 501
 502 static int dsa_dst_parse(struct dsa_switch_tree *dst)
 503 {
 504         struct dsa_switch *ds;
 505         u32 index;
 506         int err;
 507
 508         for (index = 0; index < DSA_MAX_SWITCHES; index++) {
 509                 ds = dst->ds[index];
 510                 if (!ds)
 511                         continue;
 512
 513                 err = dsa_ds_parse(dst, ds);
 514                 if (err)
 515                         return err;
 516         }
 517
 518         if (!dst->master_netdev) {
 519                 pr_warn("Tree has no master device\n");
 520                 return -EINVAL;
 521         }
 522
 523         pr_info("DSA: tree %d parsed\n", dst->tree);
 524
 525         return 0;
 526 }
 527
 528 static int dsa_parse_ports_dn(struct device_node *ports, struct dsa_switch *ds)
 529 {
 530         struct device_node *port;
 531         int err;
 532         u32 reg;
 533
 534         for_each_available_child_of_node(ports, port) {
 535                 err = of_property_read_u32(port, "reg", &reg);
 536                 if (err)
 537                         return err;
 538
 539                 if (reg >= DSA_MAX_PORTS)
 540                         return -EINVAL;
 541
 542                 ds->ports[reg].dn = port;
 543
 544                 /* Initialize enabled_port_mask now for drv->setup()
 545                  * to have access to a correct value, just like what
 546                  * net/dsa/dsa.c::dsa_switch_setup_one does.
 547                  */
 548                 if (!dsa_port_is_cpu(port))
 549                         ds->enabled_port_mask |= 1 << reg;
 550         }
 551
 552         return 0;
 553 }
 554
 555 static int dsa_parse_member(struct device_node *np, u32 *tree, u32 *index)
 556 {
 557         int err;
 558
 559         *tree = *index = 0;
 560
 561         err = of_property_read_u32_index(np, "dsa,member", 0, tree);
 562         if (err) {
 563                 /* Does not exist, but it is optional */
 564                 if (err == -EINVAL)
 565                         return 0;
 566                 return err;
 567         }
 568
 569         err = of_property_read_u32_index(np, "dsa,member", 1, index);
 570         if (err)
 571                 return err;
 572
 573         if (*index >= DSA_MAX_SWITCHES)
 574                 return -EINVAL;
 575
 576         return 0;
 577 }
 578
 579 static struct device_node *dsa_get_ports(struct dsa_switch *ds,
 580                                          struct device_node *np)
 581 {
 582         struct device_node *ports;
 583
 584         ports = of_get_child_by_name(np, "ports");
 585         if (!ports) {
 586                 dev_err(ds->dev, "no ports child node found\n");
 587                 return ERR_PTR(-EINVAL);
 588         }
 589
 590         return ports;
 591 }
 592
 593 static int _dsa_register_switch(struct dsa_switch *ds, struct device_node *np)
 594 {
 595         struct device_node *ports = dsa_get_ports(ds, np);
 596         struct dsa_switch_tree *dst;
 597         u32 tree, index;
 598         int i, err;
 599
 600         err = dsa_parse_member(np, &tree, &index);
 601         if (err)
 602                 return err;
 603
 604         if (IS_ERR(ports))
 605                 return PTR_ERR(ports);
 606
 607         err = dsa_parse_ports_dn(ports, ds);
 608         if (err)
 609                 return err;
 610
 611         dst = dsa_get_dst(tree);
 612         if (!dst) {
 613                 dst = dsa_add_dst(tree);
 614                 if (!dst)
 615                         return -ENOMEM;
 616         }
 617
 618         if (dst->ds[index]) {
 619                 err = -EBUSY;
 620                 goto out;
 621         }
 622
 623         ds->dst = dst;
 624         ds->index = index;
 625
 626         /* Initialize the routing table */
 627         for (i = 0; i < DSA_MAX_SWITCHES; ++i)
 628                 ds->rtable[i] = DSA_RTABLE_NONE;
 629
 630         dsa_dst_add_ds(dst, ds, index);
 631
 632         err = dsa_dst_complete(dst);
 633         if (err < 0)
 634                 goto out_del_dst;
 635
 636         if (err == 1) {
 637                 /* Not all switches registered yet */
 638                 err = 0;
 639                 goto out;
 640         }
 641
 642         if (dst->applied) {
 643                 pr_info("DSA: Disjoint trees?\n");
 644                 return -EINVAL;
 645         }
 646
 647         err = dsa_dst_parse(dst);
 648         if (err)
 649                 goto out_del_dst;
 650
 651         err = dsa_dst_apply(dst);
 652         if (err) {
 653                 dsa_dst_unapply(dst);
 654                 goto out_del_dst;
 655         }
 656
 657         dsa_put_dst(dst);
 658         return 0;
 659
 660 out_del_dst:
 661         dsa_dst_del_ds(dst, ds, ds->index);
 662 out:
 663         dsa_put_dst(dst);
 664
 665         return err;
 666 }
 667
 668 int dsa_register_switch(struct dsa_switch *ds, struct device_node *np)
 669 {
 670         int err;
 671
 672         mutex_lock(&dsa2_mutex);
 673         err = _dsa_register_switch(ds, np);
 674         mutex_unlock(&dsa2_mutex);
 675
 676         return err;
 677 }
 678 EXPORT_SYMBOL_GPL(dsa_register_switch);
 679
 680 static void _dsa_unregister_switch(struct dsa_switch *ds)
 681 {
 682         struct dsa_switch_tree *dst = ds->dst;
 683
 684         dsa_dst_unapply(dst);
 685
 686         dsa_dst_del_ds(dst, ds, ds->index);
 687 }
 688
 689 void dsa_unregister_switch(struct dsa_switch *ds)
 690 {
 691         mutex_lock(&dsa2_mutex);
 692         _dsa_unregister_switch(ds);
 693         mutex_unlock(&dsa2_mutex);
 694 }
 695 EXPORT_SYMBOL_GPL(dsa_unregister_switch);