dsa2.c 13.4 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
/*
 * net/dsa/dsa2.c - Hardware switch handling, binding version 2
 * Copyright (c) 2008-2009 Marvell Semiconductor
 * Copyright (c) 2013 Florian Fainelli <florian@openwrt.org>
 * Copyright (c) 2016 Andrew Lunn <andrew@lunn.ch>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */

#include <linux/device.h>
#include <linux/err.h>
#include <linux/list.h>
#include <linux/slab.h>
#include <linux/rtnetlink.h>
#include <net/dsa.h>
#include <linux/of.h>
#include <linux/of_net.h>
#include "dsa_priv.h"

static LIST_HEAD(dsa_switch_trees);
static DEFINE_MUTEX(dsa2_mutex);

static struct dsa_switch_tree *dsa_get_dst(u32 tree)
{
	struct dsa_switch_tree *dst;

	list_for_each_entry(dst, &dsa_switch_trees, list)
31 32
		if (dst->tree == tree) {
			kref_get(&dst->refcount);
33
			return dst;
34
		}
35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82
	return NULL;
}

static void dsa_free_dst(struct kref *ref)
{
	struct dsa_switch_tree *dst = container_of(ref, struct dsa_switch_tree,
						   refcount);

	list_del(&dst->list);
	kfree(dst);
}

static void dsa_put_dst(struct dsa_switch_tree *dst)
{
	kref_put(&dst->refcount, dsa_free_dst);
}

static struct dsa_switch_tree *dsa_add_dst(u32 tree)
{
	struct dsa_switch_tree *dst;

	dst = kzalloc(sizeof(*dst), GFP_KERNEL);
	if (!dst)
		return NULL;
	dst->tree = tree;
	INIT_LIST_HEAD(&dst->list);
	list_add_tail(&dsa_switch_trees, &dst->list);
	kref_init(&dst->refcount);

	return dst;
}

static void dsa_dst_add_ds(struct dsa_switch_tree *dst,
			   struct dsa_switch *ds, u32 index)
{
	kref_get(&dst->refcount);
	dst->ds[index] = ds;
}

static void dsa_dst_del_ds(struct dsa_switch_tree *dst,
			   struct dsa_switch *ds, u32 index)
{
	dst->ds[index] = NULL;
	kref_put(&dst->refcount, dsa_free_dst);
}

static bool dsa_port_is_dsa(struct device_node *port)
{
83
	return !!of_parse_phandle(port, "link", 0);
84 85 86 87
}

static bool dsa_port_is_cpu(struct device_node *port)
{
88
	return !!of_parse_phandle(port, "ethernet", 0);
89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251
}

static bool dsa_ds_find_port(struct dsa_switch *ds,
			     struct device_node *port)
{
	u32 index;

	for (index = 0; index < DSA_MAX_PORTS; index++)
		if (ds->ports[index].dn == port)
			return true;
	return false;
}

static struct dsa_switch *dsa_dst_find_port(struct dsa_switch_tree *dst,
					    struct device_node *port)
{
	struct dsa_switch *ds;
	u32 index;

	for (index = 0; index < DSA_MAX_SWITCHES; index++) {
		ds = dst->ds[index];
		if (!ds)
			continue;

		if (dsa_ds_find_port(ds, port))
			return ds;
	}

	return NULL;
}

static int dsa_port_complete(struct dsa_switch_tree *dst,
			     struct dsa_switch *src_ds,
			     struct device_node *port,
			     u32 src_port)
{
	struct device_node *link;
	int index;
	struct dsa_switch *dst_ds;

	for (index = 0;; index++) {
		link = of_parse_phandle(port, "link", index);
		if (!link)
			break;

		dst_ds = dsa_dst_find_port(dst, link);
		of_node_put(link);

		if (!dst_ds)
			return 1;

		src_ds->rtable[dst_ds->index] = src_port;
	}

	return 0;
}

/* A switch is complete if all the DSA ports phandles point to ports
 * known in the tree. A return value of 1 means the tree is not
 * complete. This is not an error condition. A value of 0 is
 * success.
 */
static int dsa_ds_complete(struct dsa_switch_tree *dst, struct dsa_switch *ds)
{
	struct device_node *port;
	u32 index;
	int err;

	for (index = 0; index < DSA_MAX_PORTS; index++) {
		port = ds->ports[index].dn;
		if (!port)
			continue;

		if (!dsa_port_is_dsa(port))
			continue;

		err = dsa_port_complete(dst, ds, port, index);
		if (err != 0)
			return err;

		ds->dsa_port_mask |= BIT(index);
	}

	return 0;
}

/* A tree is complete if all the DSA ports phandles point to ports
 * known in the tree. A return value of 1 means the tree is not
 * complete. This is not an error condition. A value of 0 is
 * success.
 */
static int dsa_dst_complete(struct dsa_switch_tree *dst)
{
	struct dsa_switch *ds;
	u32 index;
	int err;

	for (index = 0; index < DSA_MAX_SWITCHES; index++) {
		ds = dst->ds[index];
		if (!ds)
			continue;

		err = dsa_ds_complete(dst, ds);
		if (err != 0)
			return err;
	}

	return 0;
}

static int dsa_dsa_port_apply(struct device_node *port, u32 index,
			      struct dsa_switch *ds)
{
	int err;

	err = dsa_cpu_dsa_setup(ds, ds->dev, port, index);
	if (err) {
		dev_warn(ds->dev, "Failed to setup dsa port %d: %d\n",
			 index, err);
		return err;
	}

	return 0;
}

static void dsa_dsa_port_unapply(struct device_node *port, u32 index,
				 struct dsa_switch *ds)
{
	dsa_cpu_dsa_destroy(port);
}

static int dsa_cpu_port_apply(struct device_node *port, u32 index,
			      struct dsa_switch *ds)
{
	int err;

	err = dsa_cpu_dsa_setup(ds, ds->dev, port, index);
	if (err) {
		dev_warn(ds->dev, "Failed to setup cpu port %d: %d\n",
			 index, err);
		return err;
	}

	ds->cpu_port_mask |= BIT(index);

	return 0;
}

static void dsa_cpu_port_unapply(struct device_node *port, u32 index,
				 struct dsa_switch *ds)
{
	dsa_cpu_dsa_destroy(port);
	ds->cpu_port_mask &= ~BIT(index);

}

static int dsa_user_port_apply(struct device_node *port, u32 index,
			       struct dsa_switch *ds)
{
	const char *name;
	int err;

	name = of_get_property(port, "label", NULL);
252 253
	if (!name)
		name = "eth%d";
254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270

	err = dsa_slave_create(ds, ds->dev, index, name);
	if (err) {
		dev_warn(ds->dev, "Failed to create slave %d: %d\n",
			 index, err);
		return err;
	}

	return 0;
}

static void dsa_user_port_unapply(struct device_node *port, u32 index,
				  struct dsa_switch *ds)
{
	if (ds->ports[index].netdev) {
		dsa_slave_destroy(ds->ports[index].netdev);
		ds->ports[index].netdev = NULL;
271
		ds->enabled_port_mask &= ~(1 << index);
272 273 274 275 276 277 278 279 280
	}
}

static int dsa_ds_apply(struct dsa_switch_tree *dst, struct dsa_switch *ds)
{
	struct device_node *port;
	u32 index;
	int err;

281
	/* Initialize ds->phys_mii_mask before registering the slave MDIO bus
282
	 * driver and before ops->setup() has run, since the switch drivers and
283 284 285 286 287
	 * the slave MDIO bus driver rely on these values for probing PHY
	 * devices or not
	 */
	ds->phys_mii_mask = ds->enabled_port_mask;

288
	err = ds->ops->setup(ds);
289 290 291
	if (err < 0)
		return err;

292 293 294 295 296
	if (ds->ops->set_addr) {
		err = ds->ops->set_addr(ds, dst->master_netdev->dev_addr);
		if (err < 0)
			return err;
	}
297

298
	if (!ds->slave_mii_bus && ds->ops->phy_read) {
299 300 301 302 303 304 305 306 307 308 309
		ds->slave_mii_bus = devm_mdiobus_alloc(ds->dev);
		if (!ds->slave_mii_bus)
			return -ENOMEM;

		dsa_slave_mii_bus_init(ds);

		err = mdiobus_register(ds->slave_mii_bus);
		if (err < 0)
			return err;
	}

310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358
	for (index = 0; index < DSA_MAX_PORTS; index++) {
		port = ds->ports[index].dn;
		if (!port)
			continue;

		if (dsa_port_is_dsa(port)) {
			err = dsa_dsa_port_apply(port, index, ds);
			if (err)
				return err;
			continue;
		}

		if (dsa_port_is_cpu(port)) {
			err = dsa_cpu_port_apply(port, index, ds);
			if (err)
				return err;
			continue;
		}

		err = dsa_user_port_apply(port, index, ds);
		if (err)
			continue;
	}

	return 0;
}

static void dsa_ds_unapply(struct dsa_switch_tree *dst, struct dsa_switch *ds)
{
	struct device_node *port;
	u32 index;

	for (index = 0; index < DSA_MAX_PORTS; index++) {
		port = ds->ports[index].dn;
		if (!port)
			continue;

		if (dsa_port_is_dsa(port)) {
			dsa_dsa_port_unapply(port, index, ds);
			continue;
		}

		if (dsa_port_is_cpu(port)) {
			dsa_cpu_port_unapply(port, index, ds);
			continue;
		}

		dsa_user_port_unapply(port, index, ds);
	}
359

360
	if (ds->slave_mii_bus && ds->ops->phy_read)
361
		mdiobus_unregister(ds->slave_mii_bus);
362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379
}

static int dsa_dst_apply(struct dsa_switch_tree *dst)
{
	struct dsa_switch *ds;
	u32 index;
	int err;

	for (index = 0; index < DSA_MAX_SWITCHES; index++) {
		ds = dst->ds[index];
		if (!ds)
			continue;

		err = dsa_ds_apply(dst, ds);
		if (err)
			return err;
	}

380 381 382 383 384
	if (dst->ds[0]) {
		err = dsa_cpu_port_ethtool_setup(dst->ds[0]);
		if (err)
			return err;
	}
385

386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420
	/* If we use a tagging format that doesn't have an ethertype
	 * field, make sure that all packets from this point on get
	 * sent to the tag format's receive function.
	 */
	wmb();
	dst->master_netdev->dsa_ptr = (void *)dst;
	dst->applied = true;

	return 0;
}

static void dsa_dst_unapply(struct dsa_switch_tree *dst)
{
	struct dsa_switch *ds;
	u32 index;

	if (!dst->applied)
		return;

	dst->master_netdev->dsa_ptr = NULL;

	/* If we used a tagging format that doesn't have an ethertype
	 * field, make sure that all packets from this point get sent
	 * without the tag and go through the regular receive path.
	 */
	wmb();

	for (index = 0; index < DSA_MAX_SWITCHES; index++) {
		ds = dst->ds[index];
		if (!ds)
			continue;

		dsa_ds_unapply(dst, ds);
	}

421 422
	if (dst->ds[0])
		dsa_cpu_port_ethtool_restore(dst->ds[0]);
423

424 425 426 427 428 429 430 431
	pr_info("DSA: tree %d unapplied\n", dst->tree);
	dst->applied = false;
}

static int dsa_cpu_parse(struct device_node *port, u32 index,
			 struct dsa_switch_tree *dst,
			 struct dsa_switch *ds)
{
432
	enum dsa_tag_protocol tag_protocol;
433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449
	struct net_device *ethernet_dev;
	struct device_node *ethernet;

	ethernet = of_parse_phandle(port, "ethernet", 0);
	if (!ethernet)
		return -EINVAL;

	ethernet_dev = of_find_net_device_by_node(ethernet);
	if (!ethernet_dev)
		return -EPROBE_DEFER;

	if (!ds->master_netdev)
		ds->master_netdev = ethernet_dev;

	if (!dst->master_netdev)
		dst->master_netdev = ethernet_dev;

450 451
	if (!dst->cpu_switch) {
		dst->cpu_switch = ds;
452 453 454
		dst->cpu_port = index;
	}

455
	tag_protocol = ds->ops->get_tag_protocol(ds);
456
	dst->tag_ops = dsa_resolve_tag_protocol(tag_protocol);
457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530
	if (IS_ERR(dst->tag_ops)) {
		dev_warn(ds->dev, "No tagger for this switch\n");
		return PTR_ERR(dst->tag_ops);
	}

	dst->rcv = dst->tag_ops->rcv;

	return 0;
}

static int dsa_ds_parse(struct dsa_switch_tree *dst, struct dsa_switch *ds)
{
	struct device_node *port;
	u32 index;
	int err;

	for (index = 0; index < DSA_MAX_PORTS; index++) {
		port = ds->ports[index].dn;
		if (!port)
			continue;

		if (dsa_port_is_cpu(port)) {
			err = dsa_cpu_parse(port, index, dst, ds);
			if (err)
				return err;
		}
	}

	pr_info("DSA: switch %d %d parsed\n", dst->tree, ds->index);

	return 0;
}

static int dsa_dst_parse(struct dsa_switch_tree *dst)
{
	struct dsa_switch *ds;
	u32 index;
	int err;

	for (index = 0; index < DSA_MAX_SWITCHES; index++) {
		ds = dst->ds[index];
		if (!ds)
			continue;

		err = dsa_ds_parse(dst, ds);
		if (err)
			return err;
	}

	if (!dst->master_netdev) {
		pr_warn("Tree has no master device\n");
		return -EINVAL;
	}

	pr_info("DSA: tree %d parsed\n", dst->tree);

	return 0;
}

static int dsa_parse_ports_dn(struct device_node *ports, struct dsa_switch *ds)
{
	struct device_node *port;
	int err;
	u32 reg;

	for_each_available_child_of_node(ports, port) {
		err = of_property_read_u32(port, "reg", &reg);
		if (err)
			return err;

		if (reg >= DSA_MAX_PORTS)
			return -EINVAL;

		ds->ports[reg].dn = port;
531

532
		/* Initialize enabled_port_mask now for ops->setup()
533 534 535 536 537
		 * to have access to a correct value, just like what
		 * net/dsa/dsa.c::dsa_switch_setup_one does.
		 */
		if (!dsa_port_is_cpu(port))
			ds->enabled_port_mask |= 1 << reg;
538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585
	}

	return 0;
}

static int dsa_parse_member(struct device_node *np, u32 *tree, u32 *index)
{
	int err;

	*tree = *index = 0;

	err = of_property_read_u32_index(np, "dsa,member", 0, tree);
	if (err) {
		/* Does not exist, but it is optional */
		if (err == -EINVAL)
			return 0;
		return err;
	}

	err = of_property_read_u32_index(np, "dsa,member", 1, index);
	if (err)
		return err;

	if (*index >= DSA_MAX_SWITCHES)
		return -EINVAL;

	return 0;
}

static struct device_node *dsa_get_ports(struct dsa_switch *ds,
					 struct device_node *np)
{
	struct device_node *ports;

	ports = of_get_child_by_name(np, "ports");
	if (!ports) {
		dev_err(ds->dev, "no ports child node found\n");
		return ERR_PTR(-EINVAL);
	}

	return ports;
}

static int _dsa_register_switch(struct dsa_switch *ds, struct device_node *np)
{
	struct device_node *ports = dsa_get_ports(ds, np);
	struct dsa_switch_tree *dst;
	u32 tree, index;
586
	int i, err;
587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612

	err = dsa_parse_member(np, &tree, &index);
	if (err)
		return err;

	if (IS_ERR(ports))
		return PTR_ERR(ports);

	err = dsa_parse_ports_dn(ports, ds);
	if (err)
		return err;

	dst = dsa_get_dst(tree);
	if (!dst) {
		dst = dsa_add_dst(tree);
		if (!dst)
			return -ENOMEM;
	}

	if (dst->ds[index]) {
		err = -EBUSY;
		goto out;
	}

	ds->dst = dst;
	ds->index = index;
613 614 615 616 617

	/* Initialize the routing table */
	for (i = 0; i < DSA_MAX_SWITCHES; ++i)
		ds->rtable[i] = DSA_RTABLE_NONE;

618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635
	dsa_dst_add_ds(dst, ds, index);

	err = dsa_dst_complete(dst);
	if (err < 0)
		goto out_del_dst;

	if (err == 1) {
		/* Not all switches registered yet */
		err = 0;
		goto out;
	}

	if (dst->applied) {
		pr_info("DSA: Disjoint trees?\n");
		return -EINVAL;
	}

	err = dsa_dst_parse(dst);
636 637 638 639 640 641
	if (err) {
		if (err == -EPROBE_DEFER) {
			dsa_dst_del_ds(dst, ds, ds->index);
			return err;
		}

642
		goto out_del_dst;
643
	}
644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673

	err = dsa_dst_apply(dst);
	if (err) {
		dsa_dst_unapply(dst);
		goto out_del_dst;
	}

	dsa_put_dst(dst);
	return 0;

out_del_dst:
	dsa_dst_del_ds(dst, ds, ds->index);
out:
	dsa_put_dst(dst);

	return err;
}

int dsa_register_switch(struct dsa_switch *ds, struct device_node *np)
{
	int err;

	mutex_lock(&dsa2_mutex);
	err = _dsa_register_switch(ds, np);
	mutex_unlock(&dsa2_mutex);

	return err;
}
EXPORT_SYMBOL_GPL(dsa_register_switch);

674
static void _dsa_unregister_switch(struct dsa_switch *ds)
675 676 677 678 679 680 681 682 683 684 685 686 687 688 689
{
	struct dsa_switch_tree *dst = ds->dst;

	dsa_dst_unapply(dst);

	dsa_dst_del_ds(dst, ds, ds->index);
}

void dsa_unregister_switch(struct dsa_switch *ds)
{
	mutex_lock(&dsa2_mutex);
	_dsa_unregister_switch(ds);
	mutex_unlock(&dsa2_mutex);
}
EXPORT_SYMBOL_GPL(dsa_unregister_switch);