tb.c

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Thunderbolt driver - bus logic (NHI independent)
   4 *
   5 * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com>
   6 * Copyright (C) 2019, Intel Corporation
   7 */
   8
   9#include <linux/slab.h>
  10#include <linux/errno.h>
  11#include <linux/delay.h>
  12#include <linux/pm_runtime.h>
  13#include <linux/platform_data/x86/apple.h>
  14
  15#include "tb.h"
  16#include "tb_regs.h"
  17#include "tunnel.h"
  18
  19#define TB_TIMEOUT		100	/* ms */
  20#define TB_RELEASE_BW_TIMEOUT	10000	/* ms */
  21
  22/*
  23 * How many time bandwidth allocation request from graphics driver is
  24 * retried if the DP tunnel is still activating.
  25 */
  26#define TB_BW_ALLOC_RETRIES	3
  27
  28/*
  29 * Minimum bandwidth (in Mb/s) that is needed in the single transmitter/receiver
  30 * direction. This is 40G - 10% guard band bandwidth.
  31 */
  32#define TB_ASYM_MIN		(40000 * 90 / 100)
  33
  34/*
  35 * Threshold bandwidth (in Mb/s) that is used to switch the links to
  36 * asymmetric and back. This is selected as 45G which means when the
  37 * request is higher than this, we switch the link to asymmetric, and
  38 * when it is less than this we switch it back. The 45G is selected so
  39 * that we still have 27G (of the total 72G) for bulk PCIe traffic when
  40 * switching back to symmetric.
  41 */
  42#define TB_ASYM_THRESHOLD	45000
  43
  44#define MAX_GROUPS		7	/* max Group_ID is 7 */
  45
  46static unsigned int asym_threshold = TB_ASYM_THRESHOLD;
  47module_param_named(asym_threshold, asym_threshold, uint, 0444);
  48MODULE_PARM_DESC(asym_threshold,
  49		"threshold (Mb/s) when to Gen 4 switch link symmetry. 0 disables. (default: "
  50		__MODULE_STRING(TB_ASYM_THRESHOLD) ")");
  51
  52/**
  53 * struct tb_cm - Simple Thunderbolt connection manager
  54 * @tunnel_list: List of active tunnels
  55 * @dp_resources: List of available DP resources for DP tunneling
  56 * @hotplug_active: tb_handle_hotplug will stop progressing plug
  57 *		    events and exit if this is not set (it needs to
  58 *		    acquire the lock one more time). Used to drain wq
  59 *		    after cfg has been paused.
  60 * @remove_work: Work used to remove any unplugged routers after
  61 *		 runtime resume
  62 * @groups: Bandwidth groups used in this domain.
  63 */
  64struct tb_cm {
  65	struct list_head tunnel_list;
  66	struct list_head dp_resources;
  67	bool hotplug_active;
  68	struct delayed_work remove_work;
  69	struct tb_bandwidth_group groups[MAX_GROUPS];
  70};
  71
  72static inline struct tb *tcm_to_tb(struct tb_cm *tcm)
  73{
  74	return ((void *)tcm - sizeof(struct tb));
  75}
  76
  77struct tb_hotplug_event {
  78	struct delayed_work work;
  79	struct tb *tb;
  80	u64 route;
  81	u8 port;
  82	bool unplug;
  83	int retry;
  84};
  85
  86static void tb_scan_port(struct tb_port *port);
  87static void tb_handle_hotplug(struct work_struct *work);
  88static void tb_dp_resource_unavailable(struct tb *tb, struct tb_port *port,
  89				       const char *reason);
  90static void tb_queue_dp_bandwidth_request(struct tb *tb, u64 route, u8 port,
  91					  int retry, unsigned long delay);
  92
  93static void tb_queue_hotplug(struct tb *tb, u64 route, u8 port, bool unplug)
  94{
  95	struct tb_hotplug_event *ev;
  96
  97	ev = kmalloc(sizeof(*ev), GFP_KERNEL);
  98	if (!ev)
  99		return;
 100
 101	ev->tb = tb;
 102	ev->route = route;
 103	ev->port = port;
 104	ev->unplug = unplug;
 105	INIT_DELAYED_WORK(&ev->work, tb_handle_hotplug);
 106	queue_delayed_work(tb->wq, &ev->work, 0);
 107}
 108
 109/* enumeration & hot plug handling */
 110
 111static void tb_add_dp_resources(struct tb_switch *sw)
 112{
 113	struct tb_cm *tcm = tb_priv(sw->tb);
 114	struct tb_port *port;
 115
 116	tb_switch_for_each_port(sw, port) {
 117		if (!tb_port_is_dpin(port))
 118			continue;
 119
 120		if (!tb_switch_query_dp_resource(sw, port))
 121			continue;
 122
 123		/*
 124		 * If DP IN on device router exist, position it at the
 125		 * beginning of the DP resources list, so that it is used
 126		 * before DP IN of the host router. This way external GPU(s)
 127		 * will be prioritized when pairing DP IN to a DP OUT.
 128		 */
 129		if (tb_route(sw))
 130			list_add(&port->list, &tcm->dp_resources);
 131		else
 132			list_add_tail(&port->list, &tcm->dp_resources);
 133
 134		tb_port_dbg(port, "DP IN resource available\n");
 135	}
 136}
 137
 138static void tb_remove_dp_resources(struct tb_switch *sw)
 139{
 140	struct tb_cm *tcm = tb_priv(sw->tb);
 141	struct tb_port *port, *tmp;
 142
 143	/* Clear children resources first */
 144	tb_switch_for_each_port(sw, port) {
 145		if (tb_port_has_remote(port))
 146			tb_remove_dp_resources(port->remote->sw);
 147	}
 148
 149	list_for_each_entry_safe(port, tmp, &tcm->dp_resources, list) {
 150		if (port->sw == sw) {
 151			tb_port_dbg(port, "DP OUT resource unavailable\n");
 152			list_del_init(&port->list);
 153		}
 154	}
 155}
 156
 157static void tb_discover_dp_resource(struct tb *tb, struct tb_port *port)
 158{
 159	struct tb_cm *tcm = tb_priv(tb);
 160	struct tb_port *p;
 161
 162	list_for_each_entry(p, &tcm->dp_resources, list) {
 163		if (p == port)
 164			return;
 165	}
 166
 167	tb_port_dbg(port, "DP %s resource available discovered\n",
 168		    tb_port_is_dpin(port) ? "IN" : "OUT");
 169	list_add_tail(&port->list, &tcm->dp_resources);
 170}
 171
 172static void tb_discover_dp_resources(struct tb *tb)
 173{
 174	struct tb_cm *tcm = tb_priv(tb);
 175	struct tb_tunnel *tunnel;
 176
 177	list_for_each_entry(tunnel, &tcm->tunnel_list, list) {
 178		if (tb_tunnel_is_dp(tunnel))
 179			tb_discover_dp_resource(tb, tunnel->dst_port);
 180	}
 181}
 182
 183/* Enables CL states up to host router */
 184static int tb_enable_clx(struct tb_switch *sw)
 185{
 186	struct tb_cm *tcm = tb_priv(sw->tb);
 187	unsigned int clx = TB_CL0S | TB_CL1;
 188	const struct tb_tunnel *tunnel;
 189	int ret;
 190
 191	/*
 192	 * Currently only enable CLx for the first link. This is enough
 193	 * to allow the CPU to save energy at least on Intel hardware
 194	 * and makes it slightly simpler to implement. We may change
 195	 * this in the future to cover the whole topology if it turns
 196	 * out to be beneficial.
 197	 */
 198	while (sw && tb_switch_depth(sw) > 1)
 199		sw = tb_switch_parent(sw);
 200
 201	if (!sw)
 202		return 0;
 203
 204	if (tb_switch_depth(sw) != 1)
 205		return 0;
 206
 207	/*
 208	 * If we are re-enabling then check if there is an active DMA
 209	 * tunnel and in that case bail out.
 210	 */
 211	list_for_each_entry(tunnel, &tcm->tunnel_list, list) {
 212		if (tb_tunnel_is_dma(tunnel)) {
 213			if (tb_tunnel_port_on_path(tunnel, tb_upstream_port(sw)))
 214				return 0;
 215		}
 216	}
 217
 218	/*
 219	 * Initially try with CL2. If that's not supported by the
 220	 * topology try with CL0s and CL1 and then give up.
 221	 */
 222	ret = tb_switch_clx_enable(sw, clx | TB_CL2);
 223	if (ret == -EOPNOTSUPP)
 224		ret = tb_switch_clx_enable(sw, clx);
 225	return ret == -EOPNOTSUPP ? 0 : ret;
 226}
 227
 228/*
 229 * Disables CL states from @sw up to the host router.
 230 *
 231 * This can be used to figure out whether the link was setup by us or the
 232 * boot firmware so we don't accidentally enable them if they were not
 233 * enabled during discovery.
 234 */
 235static bool tb_disable_clx(struct tb_switch *sw)
 236{
 237	bool disabled = false;
 238
 239	do {
 240		int ret;
 241
 242		ret = tb_switch_clx_disable(sw);
 243		if (ret > 0)
 244			disabled = true;
 245		else if (ret < 0)
 246			tb_sw_warn(sw, "failed to disable CL states\n");
 247
 248		sw = tb_switch_parent(sw);
 249	} while (sw);
 250
 251	return disabled;
 252}
 253
 254static int tb_increase_switch_tmu_accuracy(struct device *dev, void *data)
 255{
 256	struct tb_switch *sw;
 257
 258	sw = tb_to_switch(dev);
 259	if (!sw)
 260		return 0;
 261
 262	if (tb_switch_tmu_is_configured(sw, TB_SWITCH_TMU_MODE_LOWRES)) {
 263		enum tb_switch_tmu_mode mode;
 264		int ret;
 265
 266		if (tb_switch_clx_is_enabled(sw, TB_CL1))
 267			mode = TB_SWITCH_TMU_MODE_HIFI_UNI;
 268		else
 269			mode = TB_SWITCH_TMU_MODE_HIFI_BI;
 270
 271		ret = tb_switch_tmu_configure(sw, mode);
 272		if (ret)
 273			return ret;
 274
 275		return tb_switch_tmu_enable(sw);
 276	}
 277
 278	return 0;
 279}
 280
 281static void tb_increase_tmu_accuracy(struct tb_tunnel *tunnel)
 282{
 283	struct tb_switch *sw;
 284
 285	if (!tunnel)
 286		return;
 287
 288	/*
 289	 * Once first DP tunnel is established we change the TMU
 290	 * accuracy of first depth child routers (and the host router)
 291	 * to the highest. This is needed for the DP tunneling to work
 292	 * but also allows CL0s.
 293	 *
 294	 * If both routers are v2 then we don't need to do anything as
 295	 * they are using enhanced TMU mode that allows all CLx.
 296	 */
 297	sw = tunnel->tb->root_switch;
 298	device_for_each_child(&sw->dev, NULL, tb_increase_switch_tmu_accuracy);
 299}
 300
 301static int tb_switch_tmu_hifi_uni_required(struct device *dev, void *not_used)
 302{
 303	struct tb_switch *sw = tb_to_switch(dev);
 304
 305	if (sw && tb_switch_tmu_is_enabled(sw) &&
 306	    tb_switch_tmu_is_configured(sw, TB_SWITCH_TMU_MODE_HIFI_UNI))
 307		return 1;
 308
 309	return device_for_each_child(dev, NULL,
 310				     tb_switch_tmu_hifi_uni_required);
 311}
 312
 313static bool tb_tmu_hifi_uni_required(struct tb *tb)
 314{
 315	return device_for_each_child(&tb->dev, NULL,
 316				     tb_switch_tmu_hifi_uni_required) == 1;
 317}
 318
 319static int tb_enable_tmu(struct tb_switch *sw)
 320{
 321	int ret;
 322
 323	/*
 324	 * If both routers at the end of the link are v2 we simply
 325	 * enable the enhanced uni-directional mode. That covers all
 326	 * the CL states. For v1 and before we need to use the normal
 327	 * rate to allow CL1 (when supported). Otherwise we keep the TMU
 328	 * running at the highest accuracy.
 329	 */
 330	ret = tb_switch_tmu_configure(sw,
 331			TB_SWITCH_TMU_MODE_MEDRES_ENHANCED_UNI);
 332	if (ret == -EOPNOTSUPP) {
 333		if (tb_switch_clx_is_enabled(sw, TB_CL1)) {
 334			/*
 335			 * Figure out uni-directional HiFi TMU requirements
 336			 * currently in the domain. If there are no
 337			 * uni-directional HiFi requirements we can put the TMU
 338			 * into LowRes mode.
 339			 *
 340			 * Deliberately skip bi-directional HiFi links
 341			 * as these work independently of other links
 342			 * (and they do not allow any CL states anyway).
 343			 */
 344			if (tb_tmu_hifi_uni_required(sw->tb))
 345				ret = tb_switch_tmu_configure(sw,
 346						TB_SWITCH_TMU_MODE_HIFI_UNI);
 347			else
 348				ret = tb_switch_tmu_configure(sw,
 349						TB_SWITCH_TMU_MODE_LOWRES);
 350		} else {
 351			ret = tb_switch_tmu_configure(sw, TB_SWITCH_TMU_MODE_HIFI_BI);
 352		}
 353
 354		/* If not supported, fallback to bi-directional HiFi */
 355		if (ret == -EOPNOTSUPP)
 356			ret = tb_switch_tmu_configure(sw, TB_SWITCH_TMU_MODE_HIFI_BI);
 357	}
 358	if (ret)
 359		return ret;
 360
 361	/* If it is already enabled in correct mode, don't touch it */
 362	if (tb_switch_tmu_is_enabled(sw))
 363		return 0;
 364
 365	ret = tb_switch_tmu_disable(sw);
 366	if (ret)
 367		return ret;
 368
 369	ret = tb_switch_tmu_post_time(sw);
 370	if (ret)
 371		return ret;
 372
 373	return tb_switch_tmu_enable(sw);
 374}
 375
 376static void tb_switch_discover_tunnels(struct tb_switch *sw,
 377				       struct list_head *list,
 378				       bool alloc_hopids)
 379{
 380	struct tb *tb = sw->tb;
 381	struct tb_port *port;
 382
 383	tb_switch_for_each_port(sw, port) {
 384		struct tb_tunnel *tunnel = NULL;
 385
 386		switch (port->config.type) {
 387		case TB_TYPE_DP_HDMI_IN:
 388			tunnel = tb_tunnel_discover_dp(tb, port, alloc_hopids);
 389			tb_increase_tmu_accuracy(tunnel);
 390			break;
 391
 392		case TB_TYPE_PCIE_DOWN:
 393			tunnel = tb_tunnel_discover_pci(tb, port, alloc_hopids);
 394			break;
 395
 396		case TB_TYPE_USB3_DOWN:
 397			tunnel = tb_tunnel_discover_usb3(tb, port, alloc_hopids);
 398			break;
 399
 400		default:
 401			break;
 402		}
 403
 404		if (tunnel)
 405			list_add_tail(&tunnel->list, list);
 406	}
 407
 408	tb_switch_for_each_port(sw, port) {
 409		if (tb_port_has_remote(port)) {
 410			tb_switch_discover_tunnels(port->remote->sw, list,
 411						   alloc_hopids);
 412		}
 413	}
 414}
 415
 416static int tb_port_configure_xdomain(struct tb_port *port, struct tb_xdomain *xd)
 417{
 418	if (tb_switch_is_usb4(port->sw))
 419		return usb4_port_configure_xdomain(port, xd);
 420	return tb_lc_configure_xdomain(port);
 421}
 422
 423static void tb_port_unconfigure_xdomain(struct tb_port *port)
 424{
 425	if (tb_switch_is_usb4(port->sw))
 426		usb4_port_unconfigure_xdomain(port);
 427	else
 428		tb_lc_unconfigure_xdomain(port);
 429}
 430
 431static void tb_scan_xdomain(struct tb_port *port)
 432{
 433	struct tb_switch *sw = port->sw;
 434	struct tb *tb = sw->tb;
 435	struct tb_xdomain *xd;
 436	u64 route;
 437
 438	if (!tb_is_xdomain_enabled())
 439		return;
 440
 441	route = tb_downstream_route(port);
 442	xd = tb_xdomain_find_by_route(tb, route);
 443	if (xd) {
 444		tb_xdomain_put(xd);
 445		return;
 446	}
 447
 448	xd = tb_xdomain_alloc(tb, &sw->dev, route, tb->root_switch->uuid,
 449			      NULL);
 450	if (xd) {
 451		tb_port_at(route, sw)->xdomain = xd;
 452		tb_port_configure_xdomain(port, xd);
 453		tb_xdomain_add(xd);
 454	}
 455}
 456
 457/*
 458 * Returns the first inactive port on @sw.
 459 */
 460static struct tb_port *tb_find_unused_port(struct tb_switch *sw,
 461					   enum tb_port_type type)
 462{
 463	struct tb_port *port;
 464
 465	tb_switch_for_each_port(sw, port) {
 466		if (tb_is_upstream_port(port))
 467			continue;
 468		if (port->config.type != type)
 469			continue;
 470		if (!port->cap_adap)
 471			continue;
 472		if (tb_port_is_enabled(port))
 473			continue;
 474		return port;
 475	}
 476	return NULL;
 477}
 478
 479static struct tb_port *tb_find_usb3_down(struct tb_switch *sw,
 480					 const struct tb_port *port)
 481{
 482	struct tb_port *down;
 483
 484	down = usb4_switch_map_usb3_down(sw, port);
 485	if (down && !tb_usb3_port_is_enabled(down))
 486		return down;
 487	return NULL;
 488}
 489
 490static struct tb_tunnel *tb_find_tunnel(struct tb *tb, enum tb_tunnel_type type,
 491					struct tb_port *src_port,
 492					struct tb_port *dst_port)
 493{
 494	struct tb_cm *tcm = tb_priv(tb);
 495	struct tb_tunnel *tunnel;
 496
 497	list_for_each_entry(tunnel, &tcm->tunnel_list, list) {
 498		if (tunnel->type == type &&
 499		    ((src_port && src_port == tunnel->src_port) ||
 500		     (dst_port && dst_port == tunnel->dst_port))) {
 501			return tunnel;
 502		}
 503	}
 504
 505	return NULL;
 506}
 507
 508static struct tb_tunnel *tb_find_first_usb3_tunnel(struct tb *tb,
 509						   struct tb_port *src_port,
 510						   struct tb_port *dst_port)
 511{
 512	struct tb_port *port, *usb3_down;
 513	struct tb_switch *sw;
 514
 515	/* Pick the router that is deepest in the topology */
 516	if (tb_port_path_direction_downstream(src_port, dst_port))
 517		sw = dst_port->sw;
 518	else
 519		sw = src_port->sw;
 520
 521	/* Can't be the host router */
 522	if (sw == tb->root_switch)
 523		return NULL;
 524
 525	/* Find the downstream USB4 port that leads to this router */
 526	port = tb_port_at(tb_route(sw), tb->root_switch);
 527	/* Find the corresponding host router USB3 downstream port */
 528	usb3_down = usb4_switch_map_usb3_down(tb->root_switch, port);
 529	if (!usb3_down)
 530		return NULL;
 531
 532	return tb_find_tunnel(tb, TB_TUNNEL_USB3, usb3_down, NULL);
 533}
 534
 535/**
 536 * tb_consumed_usb3_pcie_bandwidth() - Consumed USB3/PCIe bandwidth over a single link
 537 * @tb: Domain structure
 538 * @src_port: Source protocol adapter
 539 * @dst_port: Destination protocol adapter
 540 * @port: USB4 port the consumed bandwidth is calculated
 541 * @consumed_up: Consumed upstream bandwidth (Mb/s)
 542 * @consumed_down: Consumed downstream bandwidth (Mb/s)
 543 *
 544 * Calculates consumed USB3 and PCIe bandwidth at @port between path
 545 * from @src_port to @dst_port. Does not take USB3 tunnel starting from
 546 * @src_port and ending on @src_port into account because that bandwidth is
 547 * already included in as part of the "first hop" USB3 tunnel.
 548 *
 549 * Return: %0 on success, negative errno otherwise.
 550 */
 551static int tb_consumed_usb3_pcie_bandwidth(struct tb *tb,
 552					   struct tb_port *src_port,
 553					   struct tb_port *dst_port,
 554					   struct tb_port *port,
 555					   int *consumed_up,
 556					   int *consumed_down)
 557{
 558	int pci_consumed_up, pci_consumed_down;
 559	struct tb_tunnel *tunnel;
 560
 561	*consumed_up = *consumed_down = 0;
 562
 563	tunnel = tb_find_first_usb3_tunnel(tb, src_port, dst_port);
 564	if (tunnel && !tb_port_is_usb3_down(src_port) &&
 565	    !tb_port_is_usb3_up(dst_port)) {
 566		int ret;
 567
 568		ret = tb_tunnel_consumed_bandwidth(tunnel, consumed_up,
 569						   consumed_down);
 570		if (ret)
 571			return ret;
 572	}
 573
 574	/*
 575	 * If there is anything reserved for PCIe bulk traffic take it
 576	 * into account here too.
 577	 */
 578	if (tb_tunnel_reserved_pci(port, &pci_consumed_up, &pci_consumed_down)) {
 579		*consumed_up += pci_consumed_up;
 580		*consumed_down += pci_consumed_down;
 581	}
 582
 583	return 0;
 584}
 585
 586/**
 587 * tb_consumed_dp_bandwidth() - Consumed DP bandwidth over a single link
 588 * @tb: Domain structure
 589 * @src_port: Source protocol adapter
 590 * @dst_port: Destination protocol adapter
 591 * @port: USB4 port the consumed bandwidth is calculated
 592 * @consumed_up: Consumed upstream bandwidth (Mb/s)
 593 * @consumed_down: Consumed downstream bandwidth (Mb/s)
 594 *
 595 * Calculates consumed DP bandwidth at @port between path from @src_port
 596 * to @dst_port. Does not take tunnel starting from @src_port and ending
 597 * from @src_port into account.
 598 *
 599 * If there is bandwidth reserved for any of the groups between
 600 * @src_port and @dst_port (but not yet used) that is also taken into
 601 * account in the returned consumed bandwidth.
 602 *
 603 * Return: %0 on success, negative errno otherwise.
 604 */
 605static int tb_consumed_dp_bandwidth(struct tb *tb,
 606				    struct tb_port *src_port,
 607				    struct tb_port *dst_port,
 608				    struct tb_port *port,
 609				    int *consumed_up,
 610				    int *consumed_down)
 611{
 612	int group_reserved[MAX_GROUPS] = {};
 613	struct tb_cm *tcm = tb_priv(tb);
 614	struct tb_tunnel *tunnel;
 615	bool downstream;
 616	int i, ret;
 617
 618	*consumed_up = *consumed_down = 0;
 619
 620	/*
 621	 * Find all DP tunnels that cross the port and reduce
 622	 * their consumed bandwidth from the available.
 623	 */
 624	list_for_each_entry(tunnel, &tcm->tunnel_list, list) {
 625		const struct tb_bandwidth_group *group;
 626		int dp_consumed_up, dp_consumed_down;
 627
 628		if (tb_tunnel_is_invalid(tunnel))
 629			continue;
 630
 631		if (!tb_tunnel_is_dp(tunnel))
 632			continue;
 633
 634		if (!tb_tunnel_port_on_path(tunnel, port))
 635			continue;
 636
 637		/*
 638		 * Calculate what is reserved for groups crossing the
 639		 * same ports only once (as that is reserved for all the
 640		 * tunnels in the group).
 641		 */
 642		group = tunnel->src_port->group;
 643		if (group && group->reserved && !group_reserved[group->index])
 644			group_reserved[group->index] = group->reserved;
 645
 646		/*
 647		 * Ignore the DP tunnel between src_port and dst_port
 648		 * because it is the same tunnel and we may be
 649		 * re-calculating estimated bandwidth.
 650		 */
 651		if (tunnel->src_port == src_port &&
 652		    tunnel->dst_port == dst_port)
 653			continue;
 654
 655		ret = tb_tunnel_consumed_bandwidth(tunnel, &dp_consumed_up,
 656						   &dp_consumed_down);
 657		if (ret)
 658			return ret;
 659
 660		*consumed_up += dp_consumed_up;
 661		*consumed_down += dp_consumed_down;
 662	}
 663
 664	downstream = tb_port_path_direction_downstream(src_port, dst_port);
 665	for (i = 0; i < ARRAY_SIZE(group_reserved); i++) {
 666		if (downstream)
 667			*consumed_down += group_reserved[i];
 668		else
 669			*consumed_up += group_reserved[i];
 670	}
 671
 672	return 0;
 673}
 674
 675static bool tb_asym_supported(struct tb_port *src_port, struct tb_port *dst_port,
 676			      struct tb_port *port)
 677{
 678	bool downstream = tb_port_path_direction_downstream(src_port, dst_port);
 679	enum tb_link_width width;
 680
 681	if (tb_is_upstream_port(port))
 682		width = downstream ? TB_LINK_WIDTH_ASYM_RX : TB_LINK_WIDTH_ASYM_TX;
 683	else
 684		width = downstream ? TB_LINK_WIDTH_ASYM_TX : TB_LINK_WIDTH_ASYM_RX;
 685
 686	return tb_port_width_supported(port, width);
 687}
 688
 689/**
 690 * tb_maximum_bandwidth() - Maximum bandwidth over a single link
 691 * @tb: Domain structure
 692 * @src_port: Source protocol adapter
 693 * @dst_port: Destination protocol adapter
 694 * @port: USB4 port the total bandwidth is calculated
 695 * @max_up: Maximum upstream bandwidth (Mb/s)
 696 * @max_down: Maximum downstream bandwidth (Mb/s)
 697 * @include_asym: Include bandwidth if the link is switched from
 698 *		  symmetric to asymmetric
 699 *
 700 * Returns maximum possible bandwidth in @max_up and @max_down over a
 701 * single link at @port. If @include_asym is set then includes the
 702 * additional banwdith if the links are transitioned into asymmetric to
 703 * direction from @src_port to @dst_port.
 704 *
 705 * Return: %0 on success, negative errno otherwise.
 706 */
 707static int tb_maximum_bandwidth(struct tb *tb, struct tb_port *src_port,
 708				struct tb_port *dst_port, struct tb_port *port,
 709				int *max_up, int *max_down, bool include_asym)
 710{
 711	bool downstream = tb_port_path_direction_downstream(src_port, dst_port);
 712	int link_speed, link_width, up_bw, down_bw;
 713
 714	/*
 715	 * Can include asymmetric, only if it is actually supported by
 716	 * the lane adapter.
 717	 */
 718	if (!tb_asym_supported(src_port, dst_port, port))
 719		include_asym = false;
 720
 721	if (tb_is_upstream_port(port)) {
 722		link_speed = port->sw->link_speed;
 723		/*
 724		 * sw->link_width is from upstream perspective so we use
 725		 * the opposite for downstream of the host router.
 726		 */
 727		if (port->sw->link_width == TB_LINK_WIDTH_ASYM_TX) {
 728			up_bw = link_speed * 3 * 1000;
 729			down_bw = link_speed * 1 * 1000;
 730		} else if (port->sw->link_width == TB_LINK_WIDTH_ASYM_RX) {
 731			up_bw = link_speed * 1 * 1000;
 732			down_bw = link_speed * 3 * 1000;
 733		} else if (include_asym) {
 734			/*
 735			 * The link is symmetric at the moment but we
 736			 * can switch it to asymmetric as needed. Report
 737			 * this bandwidth as available (even though it
 738			 * is not yet enabled).
 739			 */
 740			if (downstream) {
 741				up_bw = link_speed * 1 * 1000;
 742				down_bw = link_speed * 3 * 1000;
 743			} else {
 744				up_bw = link_speed * 3 * 1000;
 745				down_bw = link_speed * 1 * 1000;
 746			}
 747		} else {
 748			up_bw = link_speed * port->sw->link_width * 1000;
 749			down_bw = up_bw;
 750		}
 751	} else {
 752		link_speed = tb_port_get_link_speed(port);
 753		if (link_speed < 0)
 754			return link_speed;
 755
 756		link_width = tb_port_get_link_width(port);
 757		if (link_width < 0)
 758			return link_width;
 759
 760		if (link_width == TB_LINK_WIDTH_ASYM_TX) {
 761			up_bw = link_speed * 1 * 1000;
 762			down_bw = link_speed * 3 * 1000;
 763		} else if (link_width == TB_LINK_WIDTH_ASYM_RX) {
 764			up_bw = link_speed * 3 * 1000;
 765			down_bw = link_speed * 1 * 1000;
 766		} else if (include_asym) {
 767			/*
 768			 * The link is symmetric at the moment but we
 769			 * can switch it to asymmetric as needed. Report
 770			 * this bandwidth as available (even though it
 771			 * is not yet enabled).
 772			 */
 773			if (downstream) {
 774				up_bw = link_speed * 1 * 1000;
 775				down_bw = link_speed * 3 * 1000;
 776			} else {
 777				up_bw = link_speed * 3 * 1000;
 778				down_bw = link_speed * 1 * 1000;
 779			}
 780		} else {
 781			up_bw = link_speed * link_width * 1000;
 782			down_bw = up_bw;
 783		}
 784	}
 785
 786	/* Leave 10% guard band */
 787	*max_up = up_bw - up_bw / 10;
 788	*max_down = down_bw - down_bw / 10;
 789
 790	tb_port_dbg(port, "link maximum bandwidth %d/%d Mb/s\n", *max_up, *max_down);
 791	return 0;
 792}
 793
 794/**
 795 * tb_available_bandwidth() - Available bandwidth for tunneling
 796 * @tb: Domain structure
 797 * @src_port: Source protocol adapter
 798 * @dst_port: Destination protocol adapter
 799 * @available_up: Available bandwidth upstream (Mb/s)
 800 * @available_down: Available bandwidth downstream (Mb/s)
 801 * @include_asym: Include bandwidth if the link is switched from
 802 *		  symmetric to asymmetric
 803 *
 804 * Calculates maximum available bandwidth for protocol tunneling between
 805 * @src_port and @dst_port at the moment. This is minimum of maximum
 806 * link bandwidth across all links reduced by currently consumed
 807 * bandwidth on that link.
 808 *
 809 * If @include_asym is true then includes also bandwidth that can be
 810 * added when the links are transitioned into asymmetric (but does not
 811 * transition the links).
 812 *
 813 * Return: %0 on success, negative errno otherwise.
 814 */
 815static int tb_available_bandwidth(struct tb *tb, struct tb_port *src_port,
 816				 struct tb_port *dst_port, int *available_up,
 817				 int *available_down, bool include_asym)
 818{
 819	struct tb_port *port;
 820	int ret;
 821
 822	/* Maximum possible bandwidth asymmetric Gen 4 link is 120 Gb/s */
 823	*available_up = *available_down = 120000;
 824
 825	/* Find the minimum available bandwidth over all links */
 826	tb_for_each_port_on_path(src_port, dst_port, port) {
 827		int max_up, max_down, consumed_up, consumed_down;
 828
 829		if (!tb_port_is_null(port))
 830			continue;
 831
 832		ret = tb_maximum_bandwidth(tb, src_port, dst_port, port,
 833					   &max_up, &max_down, include_asym);
 834		if (ret)
 835			return ret;
 836
 837		ret = tb_consumed_usb3_pcie_bandwidth(tb, src_port, dst_port,
 838						      port, &consumed_up,
 839						      &consumed_down);
 840		if (ret)
 841			return ret;
 842		max_up -= consumed_up;
 843		max_down -= consumed_down;
 844
 845		ret = tb_consumed_dp_bandwidth(tb, src_port, dst_port, port,
 846					       &consumed_up, &consumed_down);
 847		if (ret)
 848			return ret;
 849		max_up -= consumed_up;
 850		max_down -= consumed_down;
 851
 852		if (max_up < *available_up)
 853			*available_up = max_up;
 854		if (max_down < *available_down)
 855			*available_down = max_down;
 856	}
 857
 858	if (*available_up < 0)
 859		*available_up = 0;
 860	if (*available_down < 0)
 861		*available_down = 0;
 862
 863	return 0;
 864}
 865
 866static int tb_release_unused_usb3_bandwidth(struct tb *tb,
 867					    struct tb_port *src_port,
 868					    struct tb_port *dst_port)
 869{
 870	struct tb_tunnel *tunnel;
 871
 872	tunnel = tb_find_first_usb3_tunnel(tb, src_port, dst_port);
 873	return tunnel ? tb_tunnel_release_unused_bandwidth(tunnel) : 0;
 874}
 875
 876static void tb_reclaim_usb3_bandwidth(struct tb *tb, struct tb_port *src_port,
 877				      struct tb_port *dst_port)
 878{
 879	int ret, available_up, available_down;
 880	struct tb_tunnel *tunnel;
 881
 882	tunnel = tb_find_first_usb3_tunnel(tb, src_port, dst_port);
 883	if (!tunnel)
 884		return;
 885
 886	tb_tunnel_dbg(tunnel, "reclaiming unused bandwidth\n");
 887
 888	/*
 889	 * Calculate available bandwidth for the first hop USB3 tunnel.
 890	 * That determines the whole USB3 bandwidth for this branch.
 891	 */
 892	ret = tb_available_bandwidth(tb, tunnel->src_port, tunnel->dst_port,
 893				     &available_up, &available_down, false);
 894	if (ret) {
 895		tb_tunnel_warn(tunnel, "failed to calculate available bandwidth\n");
 896		return;
 897	}
 898
 899	tb_tunnel_dbg(tunnel, "available bandwidth %d/%d Mb/s\n", available_up,
 900		      available_down);
 901
 902	tb_tunnel_reclaim_available_bandwidth(tunnel, &available_up, &available_down);
 903}
 904
 905static int tb_tunnel_usb3(struct tb *tb, struct tb_switch *sw)
 906{
 907	struct tb_switch *parent = tb_switch_parent(sw);
 908	int ret, available_up, available_down;
 909	struct tb_port *up, *down, *port;
 910	struct tb_cm *tcm = tb_priv(tb);
 911	struct tb_tunnel *tunnel;
 912
 913	if (!tb_acpi_may_tunnel_usb3()) {
 914		tb_dbg(tb, "USB3 tunneling disabled, not creating tunnel\n");
 915		return 0;
 916	}
 917
 918	up = tb_switch_find_port(sw, TB_TYPE_USB3_UP);
 919	if (!up)
 920		return 0;
 921
 922	if (!sw->link_usb4)
 923		return 0;
 924
 925	/*
 926	 * Look up available down port. Since we are chaining it should
 927	 * be found right above this switch.
 928	 */
 929	port = tb_switch_downstream_port(sw);
 930	down = tb_find_usb3_down(parent, port);
 931	if (!down)
 932		return 0;
 933
 934	if (tb_route(parent)) {
 935		struct tb_port *parent_up;
 936		/*
 937		 * Check first that the parent switch has its upstream USB3
 938		 * port enabled. Otherwise the chain is not complete and
 939		 * there is no point setting up a new tunnel.
 940		 */
 941		parent_up = tb_switch_find_port(parent, TB_TYPE_USB3_UP);
 942		if (!parent_up || !tb_port_is_enabled(parent_up))
 943			return 0;
 944
 945		/* Make all unused bandwidth available for the new tunnel */
 946		ret = tb_release_unused_usb3_bandwidth(tb, down, up);
 947		if (ret)
 948			return ret;
 949	}
 950
 951	ret = tb_available_bandwidth(tb, down, up, &available_up, &available_down,
 952				     false);
 953	if (ret)
 954		goto err_reclaim;
 955
 956	tb_port_dbg(up, "available bandwidth for new USB3 tunnel %d/%d Mb/s\n",
 957		    available_up, available_down);
 958
 959	/*
 960	 * If the available bandwidth is less than 1.5 Gb/s notify
 961	 * userspace that the connected isochronous device may not work
 962	 * properly.
 963	 */
 964	if (available_up < 1500 || available_down < 1500)
 965		tb_tunnel_event(tb, TB_TUNNEL_LOW_BANDWIDTH, TB_TUNNEL_USB3,
 966				down, up);
 967
 968	tunnel = tb_tunnel_alloc_usb3(tb, up, down, available_up,
 969				      available_down);
 970	if (!tunnel) {
 971		ret = -ENOMEM;
 972		goto err_reclaim;
 973	}
 974
 975	if (tb_tunnel_activate(tunnel)) {
 976		tb_port_info(up,
 977			     "USB3 tunnel activation failed, aborting\n");
 978		ret = -EIO;
 979		goto err_free;
 980	}
 981
 982	list_add_tail(&tunnel->list, &tcm->tunnel_list);
 983	if (tb_route(parent))
 984		tb_reclaim_usb3_bandwidth(tb, down, up);
 985
 986	return 0;
 987
 988err_free:
 989	tb_tunnel_put(tunnel);
 990err_reclaim:
 991	if (tb_route(parent))
 992		tb_reclaim_usb3_bandwidth(tb, down, up);
 993
 994	return ret;
 995}
 996
 997static int tb_create_usb3_tunnels(struct tb_switch *sw)
 998{
 999	struct tb_port *port;
1000	int ret;
1001
1002	if (!tb_acpi_may_tunnel_usb3())
1003		return 0;
1004
1005	if (tb_route(sw)) {
1006		ret = tb_tunnel_usb3(sw->tb, sw);
1007		if (ret)
1008			return ret;
1009	}
1010
1011	tb_switch_for_each_port(sw, port) {
1012		if (!tb_port_has_remote(port))
1013			continue;
1014		ret = tb_create_usb3_tunnels(port->remote->sw);
1015		if (ret)
1016			return ret;
1017	}
1018
1019	return 0;
1020}
1021
1022/**
1023 * tb_configure_asym() - Transition links to asymmetric if needed
1024 * @tb: Domain structure
1025 * @src_port: Source adapter to start the transition
1026 * @dst_port: Destination adapter
1027 * @requested_up: Additional bandwidth (Mb/s) required upstream
1028 * @requested_down: Additional bandwidth (Mb/s) required downstream
1029 *
1030 * Transition links between @src_port and @dst_port into asymmetric, with
1031 * three lanes in the direction from @src_port towards @dst_port and one lane
1032 * in the opposite direction, if the bandwidth requirements
1033 * (requested + currently consumed) on that link exceed @asym_threshold.
1034 *
1035 * Must be called with available >= requested over all links.
1036 *
1037 * Return: %0 on success, negative errno otherwise.
1038 */
1039static int tb_configure_asym(struct tb *tb, struct tb_port *src_port,
1040			     struct tb_port *dst_port, int requested_up,
1041			     int requested_down)
1042{
1043	bool clx = false, clx_disabled = false, downstream;
1044	struct tb_switch *sw;
1045	struct tb_port *up;
1046	int ret = 0;
1047
1048	if (!asym_threshold)
1049		return 0;
1050
1051	downstream = tb_port_path_direction_downstream(src_port, dst_port);
1052	/* Pick up router deepest in the hierarchy */
1053	if (downstream)
1054		sw = dst_port->sw;
1055	else
1056		sw = src_port->sw;
1057
1058	tb_for_each_upstream_port_on_path(src_port, dst_port, up) {
1059		struct tb_port *down = tb_switch_downstream_port(up->sw);
1060		enum tb_link_width width_up, width_down;
1061		int consumed_up, consumed_down;
1062
1063		ret = tb_consumed_dp_bandwidth(tb, src_port, dst_port, up,
1064					       &consumed_up, &consumed_down);
1065		if (ret)
1066			break;
1067
1068		if (downstream) {
1069			/*
1070			 * Downstream so make sure upstream is within the 36G
1071			 * (40G - guard band 10%), and the requested is above
1072			 * what the threshold is.
1073			 */
1074			if (consumed_up + requested_up >= TB_ASYM_MIN) {
1075				ret = -ENOBUFS;
1076				break;
1077			}
1078			/* Does consumed + requested exceed the threshold */
1079			if (consumed_down + requested_down < asym_threshold)
1080				continue;
1081
1082			width_up = TB_LINK_WIDTH_ASYM_RX;
1083			width_down = TB_LINK_WIDTH_ASYM_TX;
1084		} else {
1085			/* Upstream, the opposite of above */
1086			if (consumed_down + requested_down >= TB_ASYM_MIN) {
1087				ret = -ENOBUFS;
1088				break;
1089			}
1090			if (consumed_up + requested_up < asym_threshold)
1091				continue;
1092
1093			width_up = TB_LINK_WIDTH_ASYM_TX;
1094			width_down = TB_LINK_WIDTH_ASYM_RX;
1095		}
1096
1097		if (up->sw->link_width == width_up)
1098			continue;
1099
1100		if (!tb_port_width_supported(up, width_up) ||
1101		    !tb_port_width_supported(down, width_down))
1102			continue;
1103
1104		/*
1105		 * Disable CL states before doing any transitions. We
1106		 * delayed it until now that we know there is a real
1107		 * transition taking place.
1108		 */
1109		if (!clx_disabled) {
1110			clx = tb_disable_clx(sw);
1111			clx_disabled = true;
1112		}
1113
1114		tb_sw_dbg(up->sw, "configuring asymmetric link\n");
1115
1116		/*
1117		 * Here requested + consumed > threshold so we need to
1118		 * transition the link into asymmetric now.
1119		 */
1120		ret = tb_switch_set_link_width(up->sw, width_up);
1121		if (ret) {
1122			tb_sw_warn(up->sw, "failed to set link width\n");
1123			break;
1124		}
1125	}
1126
1127	/* Re-enable CL states if they were previosly enabled */
1128	if (clx)
1129		tb_enable_clx(sw);
1130
1131	return ret;
1132}
1133
1134/**
1135 * tb_configure_sym() - Transition links to symmetric if possible
1136 * @tb: Domain structure
1137 * @src_port: Source adapter to start the transition
1138 * @dst_port: Destination adapter
1139 * @keep_asym: Keep asymmetric link if preferred
1140 *
1141 * Goes over each link from @src_port to @dst_port and tries to
1142 * transition the link to symmetric if the currently consumed bandwidth
1143 * allows and link asymmetric preference is ignored (if @keep_asym is %false).
1144 *
1145 * Return: %0 on success, negative errno otherwise.
1146 */
1147static int tb_configure_sym(struct tb *tb, struct tb_port *src_port,
1148			    struct tb_port *dst_port, bool keep_asym)
1149{
1150	bool clx = false, clx_disabled = false, downstream;
1151	struct tb_switch *sw;
1152	struct tb_port *up;
1153	int ret = 0;
1154
1155	if (!asym_threshold)
1156		return 0;
1157
1158	downstream = tb_port_path_direction_downstream(src_port, dst_port);
1159	/* Pick up router deepest in the hierarchy */
1160	if (downstream)
1161		sw = dst_port->sw;
1162	else
1163		sw = src_port->sw;
1164
1165	tb_for_each_upstream_port_on_path(src_port, dst_port, up) {
1166		int consumed_up, consumed_down;
1167
1168		/* Already symmetric */
1169		if (up->sw->link_width <= TB_LINK_WIDTH_DUAL)
1170			continue;
1171		/* Unplugged, no need to switch */
1172		if (up->sw->is_unplugged)
1173			continue;
1174
1175		ret = tb_consumed_dp_bandwidth(tb, src_port, dst_port, up,
1176					       &consumed_up, &consumed_down);
1177		if (ret)
1178			break;
1179
1180		if (downstream) {
1181			/*
1182			 * Downstream so we want the consumed_down < threshold.
1183			 * Upstream traffic should be less than 36G (40G
1184			 * guard band 10%) as the link was configured asymmetric
1185			 * already.
1186			 */
1187			if (consumed_down >= asym_threshold)
1188				continue;
1189		} else {
1190			if (consumed_up >= asym_threshold)
1191				continue;
1192		}
1193
1194		if (up->sw->link_width == TB_LINK_WIDTH_DUAL)
1195			continue;
1196
1197		/*
1198		 * Here consumed < threshold so we can transition the
1199		 * link to symmetric.
1200		 *
1201		 * However, if the router prefers asymmetric link we
1202		 * honor that (unless @keep_asym is %false).
1203		 */
1204		if (keep_asym &&
1205		    up->sw->preferred_link_width > TB_LINK_WIDTH_DUAL) {
1206			tb_sw_dbg(up->sw, "keeping preferred asymmetric link\n");
1207			continue;
1208		}
1209
1210		/* Disable CL states before doing any transitions */
1211		if (!clx_disabled) {
1212			clx = tb_disable_clx(sw);
1213			clx_disabled = true;
1214		}
1215
1216		tb_sw_dbg(up->sw, "configuring symmetric link\n");
1217
1218		ret = tb_switch_set_link_width(up->sw, TB_LINK_WIDTH_DUAL);
1219		if (ret) {
1220			tb_sw_warn(up->sw, "failed to set link width\n");
1221			break;
1222		}
1223	}
1224
1225	/* Re-enable CL states if they were previosly enabled */
1226	if (clx)
1227		tb_enable_clx(sw);
1228
1229	return ret;
1230}
1231
1232static void tb_configure_link(struct tb_port *down, struct tb_port *up,
1233			      struct tb_switch *sw)
1234{
1235	struct tb *tb = sw->tb;
1236
1237	/* Link the routers using both links if available */
1238	down->remote = up;
1239	up->remote = down;
1240	if (down->dual_link_port && up->dual_link_port) {
1241		down->dual_link_port->remote = up->dual_link_port;
1242		up->dual_link_port->remote = down->dual_link_port;
1243	}
1244
1245	/*
1246	 * Enable lane bonding if the link is currently two single lane
1247	 * links.
1248	 */
1249	if (sw->link_width < TB_LINK_WIDTH_DUAL)
1250		tb_switch_set_link_width(sw, TB_LINK_WIDTH_DUAL);
1251
1252	/*
1253	 * Device router that comes up as symmetric link is
1254	 * connected deeper in the hierarchy, we transition the links
1255	 * above into symmetric if bandwidth allows.
1256	 */
1257	if (tb_switch_depth(sw) > 1 &&
1258	    tb_port_get_link_generation(up) >= 4 &&
1259	    up->sw->link_width == TB_LINK_WIDTH_DUAL) {
1260		struct tb_port *host_port;
1261
1262		host_port = tb_port_at(tb_route(sw), tb->root_switch);
1263		tb_configure_sym(tb, host_port, up, false);
1264	}
1265
1266	/* Set the link configured */
1267	tb_switch_configure_link(sw);
1268}
1269
1270/*
1271 * tb_scan_switch() - scan for and initialize downstream switches
1272 */
1273static void tb_scan_switch(struct tb_switch *sw)
1274{
1275	struct tb_port *port;
1276
1277	pm_runtime_get_sync(&sw->dev);
1278
1279	tb_switch_for_each_port(sw, port)
1280		tb_scan_port(port);
1281
1282	pm_runtime_mark_last_busy(&sw->dev);
1283	pm_runtime_put_autosuspend(&sw->dev);
1284}
1285
1286/*
1287 * tb_scan_port() - check for and initialize switches below port
1288 */
1289static void tb_scan_port(struct tb_port *port)
1290{
1291	struct tb_cm *tcm = tb_priv(port->sw->tb);
1292	struct tb_port *upstream_port;
1293	bool discovery = false;
1294	struct tb_switch *sw;
1295
1296	if (tb_is_upstream_port(port))
1297		return;
1298
1299	if (tb_port_is_dpout(port) && tb_dp_port_hpd_is_active(port) == 1 &&
1300	    !tb_dp_port_is_enabled(port)) {
1301		tb_port_dbg(port, "DP adapter HPD set, queuing hotplug\n");
1302		tb_queue_hotplug(port->sw->tb, tb_route(port->sw), port->port,
1303				 false);
1304		return;
1305	}
1306
1307	if (port->config.type != TB_TYPE_PORT)
1308		return;
1309	if (port->dual_link_port && port->link_nr)
1310		return; /*
1311			 * Downstream switch is reachable through two ports.
1312			 * Only scan on the primary port (link_nr == 0).
1313			 */
1314
1315	if (port->usb4)
1316		pm_runtime_get_sync(&port->usb4->dev);
1317
1318	if (tb_wait_for_port(port, false) <= 0)
1319		goto out_rpm_put;
1320	if (port->remote) {
1321		tb_port_dbg(port, "port already has a remote\n");
1322		goto out_rpm_put;
1323	}
1324
1325	sw = tb_switch_alloc(port->sw->tb, &port->sw->dev,
1326			     tb_downstream_route(port));
1327	if (IS_ERR(sw)) {
1328		/*
1329		 * Make the downstream retimers available even if there
1330		 * is no router connected.
1331		 */
1332		tb_retimer_scan(port, true);
1333
1334		/*
1335		 * If there is an error accessing the connected switch
1336		 * it may be connected to another domain. Also we allow
1337		 * the other domain to be connected to a max depth switch.
1338		 */
1339		if (PTR_ERR(sw) == -EIO || PTR_ERR(sw) == -EADDRNOTAVAIL)
1340			tb_scan_xdomain(port);
1341		goto out_rpm_put;
1342	}
1343
1344	if (tb_switch_configure(sw)) {
1345		tb_switch_put(sw);
1346		goto out_rpm_put;
1347	}
1348
1349	/*
1350	 * If there was previously another domain connected remove it
1351	 * first.
1352	 */
1353	if (port->xdomain) {
1354		tb_xdomain_remove(port->xdomain);
1355		tb_port_unconfigure_xdomain(port);
1356		port->xdomain = NULL;
1357	}
1358
1359	/*
1360	 * Do not send uevents until we have discovered all existing
1361	 * tunnels and know which switches were authorized already by
1362	 * the boot firmware.
1363	 */
1364	if (!tcm->hotplug_active) {
1365		dev_set_uevent_suppress(&sw->dev, true);
1366		discovery = true;
1367	}
1368
1369	/*
1370	 * At the moment Thunderbolt 2 and beyond (devices with LC) we
1371	 * can support runtime PM.
1372	 */
1373	sw->rpm = sw->generation > 1;
1374
1375	if (tb_switch_add(sw)) {
1376		tb_switch_put(sw);
1377		goto out_rpm_put;
1378	}
1379
1380	upstream_port = tb_upstream_port(sw);
1381	tb_configure_link(port, upstream_port, sw);
1382
1383	/*
1384	 * Scan for downstream retimers. We only scan them after the
1385	 * router has been enumerated to avoid issues with certain
1386	 * Pluggable devices that expect the host to enumerate them
1387	 * within certain timeout.
1388	 */
1389	tb_retimer_scan(port, true);
1390
1391	/*
1392	 * CL0s and CL1 are enabled and supported together.
1393	 * Silently ignore CLx enabling in case CLx is not supported.
1394	 */
1395	if (discovery)
1396		tb_sw_dbg(sw, "discovery, not touching CL states\n");
1397	else if (tb_enable_clx(sw))
1398		tb_sw_warn(sw, "failed to enable CL states\n");
1399
1400	if (tb_enable_tmu(sw))
1401		tb_sw_warn(sw, "failed to enable TMU\n");
1402
1403	/*
1404	 * Configuration valid needs to be set after the TMU has been
1405	 * enabled for the upstream port of the router so we do it here.
1406	 */
1407	tb_switch_configuration_valid(sw);
1408
1409	/* Scan upstream retimers */
1410	tb_retimer_scan(upstream_port, true);
1411
1412	/*
1413	 * Create USB 3.x tunnels only when the switch is plugged to the
1414	 * domain. This is because we scan the domain also during discovery
1415	 * and want to discover existing USB 3.x tunnels before we create
1416	 * any new.
1417	 */
1418	if (tcm->hotplug_active && tb_tunnel_usb3(sw->tb, sw))
1419		tb_sw_warn(sw, "USB3 tunnel creation failed\n");
1420
1421	tb_add_dp_resources(sw);
1422	tb_scan_switch(sw);
1423
1424out_rpm_put:
1425	if (port->usb4) {
1426		pm_runtime_mark_last_busy(&port->usb4->dev);
1427		pm_runtime_put_autosuspend(&port->usb4->dev);
1428	}
1429}
1430
1431static void
1432tb_recalc_estimated_bandwidth_for_group(struct tb_bandwidth_group *group)
1433{
1434	struct tb_tunnel *first_tunnel;
1435	struct tb *tb = group->tb;
1436	struct tb_port *in;
1437	int ret;
1438
1439	tb_dbg(tb, "re-calculating bandwidth estimation for group %u\n",
1440	       group->index);
1441
1442	first_tunnel = NULL;
1443	list_for_each_entry(in, &group->ports, group_list) {
1444		int estimated_bw, estimated_up, estimated_down;
1445		struct tb_tunnel *tunnel;
1446		struct tb_port *out;
1447
1448		if (!usb4_dp_port_bandwidth_mode_enabled(in))
1449			continue;
1450
1451		tunnel = tb_find_tunnel(tb, TB_TUNNEL_DP, in, NULL);
1452		if (WARN_ON(!tunnel))
1453			break;
1454
1455		if (!first_tunnel) {
1456			/*
1457			 * Since USB3 bandwidth is shared by all DP
1458			 * tunnels under the host router USB4 port, even
1459			 * if they do not begin from the host router, we
1460			 * can release USB3 bandwidth just once and not
1461			 * for each tunnel separately.
1462			 */
1463			first_tunnel = tunnel;
1464			ret = tb_release_unused_usb3_bandwidth(tb,
1465				first_tunnel->src_port, first_tunnel->dst_port);
1466			if (ret) {
1467				tb_tunnel_warn(tunnel,
1468					"failed to release unused bandwidth\n");
1469				break;
1470			}
1471		}
1472
1473		out = tunnel->dst_port;
1474		ret = tb_available_bandwidth(tb, in, out, &estimated_up,
1475					     &estimated_down, true);
1476		if (ret) {
1477			tb_tunnel_warn(tunnel,
1478				"failed to re-calculate estimated bandwidth\n");
1479			break;
1480		}
1481
1482		/*
1483		 * Estimated bandwidth includes:
1484		 *  - already allocated bandwidth for the DP tunnel
1485		 *  - available bandwidth along the path
1486		 *  - bandwidth allocated for USB 3.x but not used.
1487		 */
1488		if (tb_tunnel_direction_downstream(tunnel))
1489			estimated_bw = estimated_down;
1490		else
1491			estimated_bw = estimated_up;
1492
1493		/*
1494		 * If there is reserved bandwidth for the group that is
1495		 * not yet released we report that too.
1496		 */
1497		tb_tunnel_dbg(tunnel,
1498			      "re-calculated estimated bandwidth %u (+ %u reserved) = %u Mb/s\n",
1499			      estimated_bw, group->reserved,
1500			      estimated_bw + group->reserved);
1501
1502		if (usb4_dp_port_set_estimated_bandwidth(in,
1503				estimated_bw + group->reserved))
1504			tb_tunnel_warn(tunnel,
1505				       "failed to update estimated bandwidth\n");
1506	}
1507
1508	if (first_tunnel)
1509		tb_reclaim_usb3_bandwidth(tb, first_tunnel->src_port,
1510					  first_tunnel->dst_port);
1511
1512	tb_dbg(tb, "bandwidth estimation for group %u done\n", group->index);
1513}
1514
1515static void tb_recalc_estimated_bandwidth(struct tb *tb)
1516{
1517	struct tb_cm *tcm = tb_priv(tb);
1518	int i;
1519
1520	tb_dbg(tb, "bandwidth consumption changed, re-calculating estimated bandwidth\n");
1521
1522	for (i = 0; i < ARRAY_SIZE(tcm->groups); i++) {
1523		struct tb_bandwidth_group *group = &tcm->groups[i];
1524
1525		if (!list_empty(&group->ports))
1526			tb_recalc_estimated_bandwidth_for_group(group);
1527	}
1528
1529	tb_dbg(tb, "bandwidth re-calculation done\n");
1530}
1531
1532static bool __release_group_bandwidth(struct tb_bandwidth_group *group)
1533{
1534	if (group->reserved) {
1535		tb_dbg(group->tb, "group %d released total %d Mb/s\n", group->index,
1536			group->reserved);
1537		group->reserved = 0;
1538		return true;
1539	}
1540	return false;
1541}
1542
1543static void __configure_group_sym(struct tb_bandwidth_group *group)
1544{
1545	struct tb_tunnel *tunnel;
1546	struct tb_port *in;
1547
1548	if (list_empty(&group->ports))
1549		return;
1550
1551	/*
1552	 * All the tunnels in the group go through the same USB4 links
1553	 * so we find the first one here and pass the IN and OUT
1554	 * adapters to tb_configure_sym() which now transitions the
1555	 * links back to symmetric if bandwidth requirement < asym_threshold.
1556	 *
1557	 * We do this here to avoid unnecessary transitions (for example
1558	 * if the graphics released bandwidth for other tunnel in the
1559	 * same group).
1560	 */
1561	in = list_first_entry(&group->ports, struct tb_port, group_list);
1562	tunnel = tb_find_tunnel(group->tb, TB_TUNNEL_DP, in, NULL);
1563	if (tunnel)
1564		tb_configure_sym(group->tb, in, tunnel->dst_port, true);
1565}
1566
1567static void tb_bandwidth_group_release_work(struct work_struct *work)
1568{
1569	struct tb_bandwidth_group *group =
1570		container_of(work, typeof(*group), release_work.work);
1571	struct tb *tb = group->tb;
1572
1573	mutex_lock(&tb->lock);
1574	if (__release_group_bandwidth(group))
1575		tb_recalc_estimated_bandwidth(tb);
1576	__configure_group_sym(group);
1577	mutex_unlock(&tb->lock);
1578}
1579
1580static void tb_init_bandwidth_groups(struct tb_cm *tcm)
1581{
1582	int i;
1583
1584	for (i = 0; i < ARRAY_SIZE(tcm->groups); i++) {
1585		struct tb_bandwidth_group *group = &tcm->groups[i];
1586
1587		group->tb = tcm_to_tb(tcm);
1588		group->index = i + 1;
1589		INIT_LIST_HEAD(&group->ports);
1590		INIT_DELAYED_WORK(&group->release_work,
1591				  tb_bandwidth_group_release_work);
1592	}
1593}
1594
1595static void tb_bandwidth_group_attach_port(struct tb_bandwidth_group *group,
1596					   struct tb_port *in)
1597{
1598	if (!group || WARN_ON(in->group))
1599		return;
1600
1601	in->group = group;
1602	list_add_tail(&in->group_list, &group->ports);
1603
1604	tb_port_dbg(in, "attached to bandwidth group %d\n", group->index);
1605}
1606
1607static struct tb_bandwidth_group *tb_find_free_bandwidth_group(struct tb_cm *tcm)
1608{
1609	int i;
1610
1611	for (i = 0; i < ARRAY_SIZE(tcm->groups); i++) {
1612		struct tb_bandwidth_group *group = &tcm->groups[i];
1613
1614		if (list_empty(&group->ports))
1615			return group;
1616	}
1617
1618	return NULL;
1619}
1620
1621static struct tb_bandwidth_group *
1622tb_attach_bandwidth_group(struct tb_cm *tcm, struct tb_port *in,
1623			  struct tb_port *out)
1624{
1625	struct tb_bandwidth_group *group;
1626	struct tb_tunnel *tunnel;
1627
1628	/*
1629	 * Find all DP tunnels that go through all the same USB4 links
1630	 * as this one. Because we always setup tunnels the same way we
1631	 * can just check for the routers at both ends of the tunnels
1632	 * and if they are the same we have a match.
1633	 */
1634	list_for_each_entry(tunnel, &tcm->tunnel_list, list) {
1635		if (!tb_tunnel_is_dp(tunnel))
1636			continue;
1637
1638		if (tunnel->src_port->sw == in->sw &&
1639		    tunnel->dst_port->sw == out->sw) {
1640			group = tunnel->src_port->group;
1641			if (group) {
1642				tb_bandwidth_group_attach_port(group, in);
1643				return group;
1644			}
1645		}
1646	}
1647
1648	/* Pick up next available group then */
1649	group = tb_find_free_bandwidth_group(tcm);
1650	if (group)
1651		tb_bandwidth_group_attach_port(group, in);
1652	else
1653		tb_port_warn(in, "no available bandwidth groups\n");
1654
1655	return group;
1656}
1657
1658static void tb_discover_bandwidth_group(struct tb_cm *tcm, struct tb_port *in,
1659					struct tb_port *out)
1660{
1661	if (usb4_dp_port_bandwidth_mode_enabled(in)) {
1662		int index, i;
1663
1664		index = usb4_dp_port_group_id(in);
1665		for (i = 0; i < ARRAY_SIZE(tcm->groups); i++) {
1666			if (tcm->groups[i].index == index) {
1667				tb_bandwidth_group_attach_port(&tcm->groups[i], in);
1668				return;
1669			}
1670		}
1671	}
1672
1673	tb_attach_bandwidth_group(tcm, in, out);
1674}
1675
1676static void tb_detach_bandwidth_group(struct tb_port *in)
1677{
1678	struct tb_bandwidth_group *group = in->group;
1679
1680	if (group) {
1681		in->group = NULL;
1682		list_del_init(&in->group_list);
1683
1684		tb_port_dbg(in, "detached from bandwidth group %d\n", group->index);
1685
1686		/* No more tunnels so release the reserved bandwidth if any */
1687		if (list_empty(&group->ports)) {
1688			cancel_delayed_work(&group->release_work);
1689			__release_group_bandwidth(group);
1690		}
1691	}
1692}
1693
1694static void tb_discover_tunnels(struct tb *tb)
1695{
1696	struct tb_cm *tcm = tb_priv(tb);
1697	struct tb_tunnel *tunnel;
1698
1699	tb_switch_discover_tunnels(tb->root_switch, &tcm->tunnel_list, true);
1700
1701	list_for_each_entry(tunnel, &tcm->tunnel_list, list) {
1702		if (tb_tunnel_is_pci(tunnel)) {
1703			struct tb_switch *parent = tunnel->dst_port->sw;
1704
1705			while (parent != tunnel->src_port->sw) {
1706				parent->boot = true;
1707				parent = tb_switch_parent(parent);
1708			}
1709		} else if (tb_tunnel_is_dp(tunnel)) {
1710			struct tb_port *in = tunnel->src_port;
1711			struct tb_port *out = tunnel->dst_port;
1712
1713			/* Keep the domain from powering down */
1714			pm_runtime_get_sync(&in->sw->dev);
1715			pm_runtime_get_sync(&out->sw->dev);
1716
1717			tb_discover_bandwidth_group(tcm, in, out);
1718		}
1719	}
1720}
1721
1722static void tb_deactivate_and_free_tunnel(struct tb_tunnel *tunnel)
1723{
1724	struct tb_port *src_port, *dst_port;
1725	struct tb *tb;
1726
1727	if (!tunnel)
1728		return;
1729
1730	tb_tunnel_deactivate(tunnel);
1731	list_del(&tunnel->list);
1732
1733	tb = tunnel->tb;
1734	src_port = tunnel->src_port;
1735	dst_port = tunnel->dst_port;
1736
1737	switch (tunnel->type) {
1738	case TB_TUNNEL_DP:
1739		tb_detach_bandwidth_group(src_port);
1740		/*
1741		 * In case of DP tunnel make sure the DP IN resource is
1742		 * deallocated properly.
1743		 */
1744		tb_switch_dealloc_dp_resource(src_port->sw, src_port);
1745		/*
1746		 * If bandwidth on a link is < asym_threshold
1747		 * transition the link to symmetric.
1748		 */
1749		tb_configure_sym(tb, src_port, dst_port, true);
1750		/* Now we can allow the domain to runtime suspend again */
1751		pm_runtime_mark_last_busy(&dst_port->sw->dev);
1752		pm_runtime_put_autosuspend(&dst_port->sw->dev);
1753		pm_runtime_mark_last_busy(&src_port->sw->dev);
1754		pm_runtime_put_autosuspend(&src_port->sw->dev);
1755		fallthrough;
1756
1757	case TB_TUNNEL_USB3:
1758		tb_reclaim_usb3_bandwidth(tb, src_port, dst_port);
1759		break;
1760
1761	default:
1762		/*
1763		 * PCIe and DMA tunnels do not consume guaranteed
1764		 * bandwidth.
1765		 */
1766		break;
1767	}
1768
1769	tb_tunnel_put(tunnel);
1770}
1771
1772/*
1773 * tb_free_invalid_tunnels() - destroy tunnels of devices that have gone away
1774 */
1775static void tb_free_invalid_tunnels(struct tb *tb)
1776{
1777	struct tb_cm *tcm = tb_priv(tb);
1778	struct tb_tunnel *tunnel;
1779	struct tb_tunnel *n;
1780
1781	list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) {
1782		if (tb_tunnel_is_invalid(tunnel))
1783			tb_deactivate_and_free_tunnel(tunnel);
1784	}
1785}
1786
1787/*
1788 * tb_free_unplugged_children() - traverse hierarchy and free unplugged switches
1789 */
1790static void tb_free_unplugged_children(struct tb_switch *sw)
1791{
1792	struct tb_port *port;
1793
1794	tb_switch_for_each_port(sw, port) {
1795		if (!tb_port_has_remote(port))
1796			continue;
1797
1798		if (port->remote->sw->is_unplugged) {
1799			tb_retimer_remove_all(port);
1800			tb_remove_dp_resources(port->remote->sw);
1801			tb_switch_unconfigure_link(port->remote->sw);
1802			tb_switch_set_link_width(port->remote->sw,
1803						 TB_LINK_WIDTH_SINGLE);
1804			tb_switch_remove(port->remote->sw);
1805			port->remote = NULL;
1806			if (port->dual_link_port)
1807				port->dual_link_port->remote = NULL;
1808		} else {
1809			tb_free_unplugged_children(port->remote->sw);
1810		}
1811	}
1812}
1813
1814static struct tb_port *tb_find_pcie_down(struct tb_switch *sw,
1815					 const struct tb_port *port)
1816{
1817	struct tb_port *down = NULL;
1818
1819	/*
1820	 * To keep plugging devices consistently in the same PCIe
1821	 * hierarchy, do mapping here for switch downstream PCIe ports.
1822	 */
1823	if (tb_switch_is_usb4(sw)) {
1824		down = usb4_switch_map_pcie_down(sw, port);
1825	} else if (!tb_route(sw)) {
1826		int phy_port = tb_phy_port_from_link(port->port);
1827		int index;
1828
1829		/*
1830		 * Hard-coded Thunderbolt port to PCIe down port mapping
1831		 * per controller.
1832		 */
1833		if (tb_switch_is_cactus_ridge(sw) ||
1834		    tb_switch_is_alpine_ridge(sw))
1835			index = !phy_port ? 6 : 7;
1836		else if (tb_switch_is_falcon_ridge(sw))
1837			index = !phy_port ? 6 : 8;
1838		else if (tb_switch_is_titan_ridge(sw))
1839			index = !phy_port ? 8 : 9;
1840		else
1841			goto out;
1842
1843		/* Validate the hard-coding */
1844		if (WARN_ON(index > sw->config.max_port_number))
1845			goto out;
1846
1847		down = &sw->ports[index];
1848	}
1849
1850	if (down) {
1851		if (WARN_ON(!tb_port_is_pcie_down(down)))
1852			goto out;
1853		if (tb_pci_port_is_enabled(down))
1854			goto out;
1855
1856		return down;
1857	}
1858
1859out:
1860	return tb_find_unused_port(sw, TB_TYPE_PCIE_DOWN);
1861}
1862
1863static struct tb_port *tb_find_dp_out(struct tb *tb, struct tb_port *in)
1864{
1865	struct tb_port *host_port, *port;
1866	struct tb_cm *tcm = tb_priv(tb);
1867
1868	host_port = tb_route(in->sw) ?
1869		tb_port_at(tb_route(in->sw), tb->root_switch) : NULL;
1870
1871	list_for_each_entry(port, &tcm->dp_resources, list) {
1872		if (!tb_port_is_dpout(port))
1873			continue;
1874
1875		if (tb_port_is_enabled(port)) {
1876			tb_port_dbg(port, "DP OUT in use\n");
1877			continue;
1878		}
1879
1880		/* Needs to be on different routers */
1881		if (in->sw == port->sw) {
1882			tb_port_dbg(port, "skipping DP OUT on same router\n");
1883			continue;
1884		}
1885
1886		tb_port_dbg(port, "DP OUT available\n");
1887
1888		/*
1889		 * Keep the DP tunnel under the topology starting from
1890		 * the same host router downstream port.
1891		 */
1892		if (host_port && tb_route(port->sw)) {
1893			struct tb_port *p;
1894
1895			p = tb_port_at(tb_route(port->sw), tb->root_switch);
1896			if (p != host_port)
1897				continue;
1898		}
1899
1900		return port;
1901	}
1902
1903	return NULL;
1904}
1905
1906static void tb_dp_tunnel_active(struct tb_tunnel *tunnel, void *data)
1907{
1908	struct tb_port *in = tunnel->src_port;
1909	struct tb_port *out = tunnel->dst_port;
1910	struct tb *tb = data;
1911
1912	mutex_lock(&tb->lock);
1913	if (tb_tunnel_is_active(tunnel)) {
1914		int consumed_up, consumed_down, ret;
1915
1916		tb_tunnel_dbg(tunnel, "DPRX capabilities read completed\n");
1917
1918		/* If fail reading tunnel's consumed bandwidth, tear it down */
1919		ret = tb_tunnel_consumed_bandwidth(tunnel, &consumed_up,
1920						   &consumed_down);
1921		if (ret) {
1922			tb_tunnel_warn(tunnel,
1923				       "failed to read consumed bandwidth, tearing down\n");
1924			tb_deactivate_and_free_tunnel(tunnel);
1925		} else {
1926			tb_reclaim_usb3_bandwidth(tb, in, out);
1927			/*
1928			 * Transition the links to asymmetric if the
1929			 * consumption exceeds the threshold.
1930			 */
1931			tb_configure_asym(tb, in, out, consumed_up,
1932					  consumed_down);
1933			/*
1934			 * Update the domain with the new bandwidth
1935			 * estimation.
1936			 */
1937			tb_recalc_estimated_bandwidth(tb);
1938			/*
1939			 * In case DP tunnel exists, change host
1940			 * router's 1st children TMU mode to HiFi for
1941			 * CL0s to work.
1942			 */
1943			tb_increase_tmu_accuracy(tunnel);
1944		}
1945	} else {
1946		struct tb_port *in = tunnel->src_port;
1947
1948		/*
1949		 * This tunnel failed to establish. This means DPRX
1950		 * negotiation most likely did not complete which
1951		 * happens either because there is no graphics driver
1952		 * loaded or not all DP cables where connected to the
1953		 * discrete router.
1954		 *
1955		 * In both cases we remove the DP IN adapter from the
1956		 * available resources as it is not usable. This will
1957		 * also tear down the tunnel and try to re-use the
1958		 * released DP OUT.
1959		 *
1960		 * It will be added back only if there is hotplug for
1961		 * the DP IN again.
1962		 */
1963		tb_tunnel_warn(tunnel, "not active, tearing down\n");
1964		tb_dp_resource_unavailable(tb, in, "DPRX negotiation failed");
1965	}
1966	mutex_unlock(&tb->lock);
1967
1968	tb_domain_put(tb);
1969}
1970
1971static void tb_tunnel_one_dp(struct tb *tb, struct tb_port *in,
1972			     struct tb_port *out)
1973{
1974	int available_up, available_down, ret, link_nr;
1975	struct tb_cm *tcm = tb_priv(tb);
1976	struct tb_tunnel *tunnel;
1977
1978	/*
1979	 * This is only applicable to links that are not bonded (so
1980	 * when Thunderbolt 1 hardware is involved somewhere in the
1981	 * topology). For these try to share the DP bandwidth between
1982	 * the two lanes.
1983	 */
1984	link_nr = 1;
1985	list_for_each_entry(tunnel, &tcm->tunnel_list, list) {
1986		if (tb_tunnel_is_dp(tunnel)) {
1987			link_nr = 0;
1988			break;
1989		}
1990	}
1991
1992	/*
1993	 * DP stream needs the domain to be active so runtime resume
1994	 * both ends of the tunnel.
1995	 *
1996	 * This should bring the routers in the middle active as well
1997	 * and keeps the domain from runtime suspending while the DP
1998	 * tunnel is active.
1999	 */
2000	pm_runtime_get_sync(&in->sw->dev);
2001	pm_runtime_get_sync(&out->sw->dev);
2002
2003	if (tb_switch_alloc_dp_resource(in->sw, in)) {
2004		tb_port_dbg(in, "no resource available for DP IN, not tunneling\n");
2005		goto err_rpm_put;
2006	}
2007
2008	if (!tb_attach_bandwidth_group(tcm, in, out))
2009		goto err_dealloc_dp;
2010
2011	/* Make all unused USB3 bandwidth available for the new DP tunnel */
2012	ret = tb_release_unused_usb3_bandwidth(tb, in, out);
2013	if (ret) {
2014		tb_warn(tb, "failed to release unused bandwidth\n");
2015		goto err_detach_group;
2016	}
2017
2018	ret = tb_available_bandwidth(tb, in, out, &available_up, &available_down,
2019				     true);
2020	if (ret) {
2021		tb_tunnel_event(tb, TB_TUNNEL_NO_BANDWIDTH, TB_TUNNEL_DP, in, out);
2022		goto err_reclaim_usb;
2023	}
2024
2025	tb_dbg(tb, "available bandwidth for new DP tunnel %u/%u Mb/s\n",
2026	       available_up, available_down);
2027
2028	tunnel = tb_tunnel_alloc_dp(tb, in, out, link_nr, available_up,
2029				    available_down, tb_dp_tunnel_active,
2030				    tb_domain_get(tb));
2031	if (!tunnel) {
2032		tb_port_dbg(out, "could not allocate DP tunnel\n");
2033		goto err_reclaim_usb;
2034	}
2035
2036	list_add_tail(&tunnel->list, &tcm->tunnel_list);
2037
2038	ret = tb_tunnel_activate(tunnel);
2039	if (ret && ret != -EINPROGRESS) {
2040		tb_port_info(out, "DP tunnel activation failed, aborting\n");
2041		list_del(&tunnel->list);
2042		goto err_free;
2043	}
2044
2045	return;
2046
2047err_free:
2048	tb_tunnel_put(tunnel);
2049err_reclaim_usb:
2050	tb_reclaim_usb3_bandwidth(tb, in, out);
2051	tb_domain_put(tb);
2052err_detach_group:
2053	tb_detach_bandwidth_group(in);
2054err_dealloc_dp:
2055	tb_switch_dealloc_dp_resource(in->sw, in);
2056err_rpm_put:
2057	pm_runtime_mark_last_busy(&out->sw->dev);
2058	pm_runtime_put_autosuspend(&out->sw->dev);
2059	pm_runtime_mark_last_busy(&in->sw->dev);
2060	pm_runtime_put_autosuspend(&in->sw->dev);
2061}
2062
2063static void tb_tunnel_dp(struct tb *tb)
2064{
2065	struct tb_cm *tcm = tb_priv(tb);
2066	struct tb_port *port, *in, *out;
2067
2068	if (!tb_acpi_may_tunnel_dp()) {
2069		tb_dbg(tb, "DP tunneling disabled, not creating tunnel\n");
2070		return;
2071	}
2072
2073	/*
2074	 * Find pair of inactive DP IN and DP OUT adapters and then
2075	 * establish a DP tunnel between them.
2076	 */
2077	tb_dbg(tb, "looking for DP IN <-> DP OUT pairs:\n");
2078
2079	in = NULL;
2080	out = NULL;
2081	list_for_each_entry(port, &tcm->dp_resources, list) {
2082		if (!tb_port_is_dpin(port))
2083			continue;
2084
2085		if (tb_port_is_enabled(port)) {
2086			tb_port_dbg(port, "DP IN in use\n");
2087			continue;
2088		}
2089
2090		in = port;
2091		tb_port_dbg(in, "DP IN available\n");
2092
2093		out = tb_find_dp_out(tb, port);
2094		if (out)
2095			tb_tunnel_one_dp(tb, in, out);
2096		else
2097			tb_port_dbg(in, "no suitable DP OUT adapter available, not tunneling\n");
2098	}
2099
2100	if (!in)
2101		tb_dbg(tb, "no suitable DP IN adapter available, not tunneling\n");
2102}
2103
2104static void tb_enter_redrive(struct tb_port *port)
2105{
2106	struct tb_switch *sw = port->sw;
2107
2108	if (!(sw->quirks & QUIRK_KEEP_POWER_IN_DP_REDRIVE))
2109		return;
2110
2111	/*
2112	 * If we get hot-unplug for the DP IN port of the host router
2113	 * and the DP resource is not available anymore it means there
2114	 * is a monitor connected directly to the Type-C port and we are
2115	 * in "redrive" mode. For this to work we cannot enter RTD3 so
2116	 * we bump up the runtime PM reference count here.
2117	 */
2118	if (!tb_port_is_dpin(port))
2119		return;
2120	if (tb_route(sw))
2121		return;
2122	if (!tb_switch_query_dp_resource(sw, port)) {
2123		port->redrive = true;
2124		pm_runtime_get(&sw->dev);
2125		tb_port_dbg(port, "enter redrive mode, keeping powered\n");
2126	}
2127}
2128
2129static void tb_exit_redrive(struct tb_port *port)
2130{
2131	struct tb_switch *sw = port->sw;
2132
2133	if (!(sw->quirks & QUIRK_KEEP_POWER_IN_DP_REDRIVE))
2134		return;
2135
2136	if (!tb_port_is_dpin(port))
2137		return;
2138	if (tb_route(sw))
2139		return;
2140	if (port->redrive && tb_switch_query_dp_resource(sw, port)) {
2141		port->redrive = false;
2142		pm_runtime_put(&sw->dev);
2143		tb_port_dbg(port, "exit redrive mode\n");
2144	}
2145}
2146
2147static void tb_switch_enter_redrive(struct tb_switch *sw)
2148{
2149	struct tb_port *port;
2150
2151	tb_switch_for_each_port(sw, port)
2152		tb_enter_redrive(port);
2153}
2154
2155/*
2156 * Called during system and runtime suspend to forcefully exit redrive
2157 * mode without querying whether the resource is available.
2158 */
2159static void tb_switch_exit_redrive(struct tb_switch *sw)
2160{
2161	struct tb_port *port;
2162
2163	if (!(sw->quirks & QUIRK_KEEP_POWER_IN_DP_REDRIVE))
2164		return;
2165
2166	tb_switch_for_each_port(sw, port) {
2167		if (!tb_port_is_dpin(port))
2168			continue;
2169
2170		if (port->redrive) {
2171			port->redrive = false;
2172			pm_runtime_put(&sw->dev);
2173			tb_port_dbg(port, "exit redrive mode\n");
2174		}
2175	}
2176}
2177
2178static void tb_dp_resource_unavailable(struct tb *tb, struct tb_port *port,
2179				       const char *reason)
2180{
2181	struct tb_port *in, *out;
2182	struct tb_tunnel *tunnel;
2183
2184	if (tb_port_is_dpin(port)) {
2185		tb_port_dbg(port, "DP IN resource unavailable: %s\n", reason);
2186		in = port;
2187		out = NULL;
2188	} else {
2189		tb_port_dbg(port, "DP OUT resource unavailable: %s\n", reason);
2190		in = NULL;
2191		out = port;
2192	}
2193
2194	tunnel = tb_find_tunnel(tb, TB_TUNNEL_DP, in, out);
2195	if (tunnel)
2196		tb_deactivate_and_free_tunnel(tunnel);
2197	else
2198		tb_enter_redrive(port);
2199	list_del_init(&port->list);
2200
2201	/*
2202	 * See if there is another DP OUT port that can be used for
2203	 * to create another tunnel.
2204	 */
2205	tb_recalc_estimated_bandwidth(tb);
2206	tb_tunnel_dp(tb);
2207}
2208
2209static void tb_dp_resource_available(struct tb *tb, struct tb_port *port)
2210{
2211	struct tb_cm *tcm = tb_priv(tb);
2212	struct tb_port *p;
2213
2214	if (tb_port_is_enabled(port))
2215		return;
2216
2217	list_for_each_entry(p, &tcm->dp_resources, list) {
2218		if (p == port)
2219			return;
2220	}
2221
2222	tb_port_dbg(port, "DP %s resource available after hotplug\n",
2223		    tb_port_is_dpin(port) ? "IN" : "OUT");
2224	list_add_tail(&port->list, &tcm->dp_resources);
2225	tb_exit_redrive(port);
2226
2227	/* Look for suitable DP IN <-> DP OUT pairs now */
2228	tb_tunnel_dp(tb);
2229}
2230
2231static void tb_disconnect_and_release_dp(struct tb *tb)
2232{
2233	struct tb_cm *tcm = tb_priv(tb);
2234	struct tb_tunnel *tunnel, *n;
2235
2236	/*
2237	 * Tear down all DP tunnels and release their resources. They
2238	 * will be re-established after resume based on plug events.
2239	 */
2240	list_for_each_entry_safe_reverse(tunnel, n, &tcm->tunnel_list, list) {
2241		if (tb_tunnel_is_dp(tunnel))
2242			tb_deactivate_and_free_tunnel(tunnel);
2243	}
2244
2245	while (!list_empty(&tcm->dp_resources)) {
2246		struct tb_port *port;
2247
2248		port = list_first_entry(&tcm->dp_resources,
2249					struct tb_port, list);
2250		list_del_init(&port->list);
2251	}
2252}
2253
2254static int tb_disconnect_pci(struct tb *tb, struct tb_switch *sw)
2255{
2256	struct tb_tunnel *tunnel;
2257	struct tb_port *up;
2258
2259	up = tb_switch_find_port(sw, TB_TYPE_PCIE_UP);
2260	if (WARN_ON(!up))
2261		return -ENODEV;
2262
2263	tunnel = tb_find_tunnel(tb, TB_TUNNEL_PCI, NULL, up);
2264	if (WARN_ON(!tunnel))
2265		return -ENODEV;
2266
2267	tb_switch_xhci_disconnect(sw);
2268
2269	tb_tunnel_deactivate(tunnel);
2270	list_del(&tunnel->list);
2271	tb_tunnel_put(tunnel);
2272	return 0;
2273}
2274
2275static int tb_tunnel_pci(struct tb *tb, struct tb_switch *sw)
2276{
2277	struct tb_port *up, *down, *port;
2278	struct tb_cm *tcm = tb_priv(tb);
2279	struct tb_tunnel *tunnel;
2280
2281	up = tb_switch_find_port(sw, TB_TYPE_PCIE_UP);
2282	if (!up)
2283		return 0;
2284
2285	/*
2286	 * Look up available down port. Since we are chaining it should
2287	 * be found right above this switch.
2288	 */
2289	port = tb_switch_downstream_port(sw);
2290	down = tb_find_pcie_down(tb_switch_parent(sw), port);
2291	if (!down)
2292		return 0;
2293
2294	tunnel = tb_tunnel_alloc_pci(tb, up, down);
2295	if (!tunnel)
2296		return -ENOMEM;
2297
2298	if (tb_tunnel_activate(tunnel)) {
2299		tb_port_info(up,
2300			     "PCIe tunnel activation failed, aborting\n");
2301		tb_tunnel_put(tunnel);
2302		return -EIO;
2303	}
2304
2305	/*
2306	 * PCIe L1 is needed to enable CL0s for Titan Ridge so enable it
2307	 * here.
2308	 */
2309	if (tb_switch_pcie_l1_enable(sw))
2310		tb_sw_warn(sw, "failed to enable PCIe L1 for Titan Ridge\n");
2311
2312	if (tb_switch_xhci_connect(sw))
2313		tb_sw_warn(sw, "failed to connect xHCI\n");
2314
2315	list_add_tail(&tunnel->list, &tcm->tunnel_list);
2316	return 0;
2317}
2318
2319static int tb_approve_xdomain_paths(struct tb *tb, struct tb_xdomain *xd,
2320				    int transmit_path, int transmit_ring,
2321				    int receive_path, int receive_ring)
2322{
2323	struct tb_cm *tcm = tb_priv(tb);
2324	struct tb_port *nhi_port, *dst_port;
2325	struct tb_tunnel *tunnel;
2326	struct tb_switch *sw;
2327	int ret;
2328
2329	sw = tb_to_switch(xd->dev.parent);
2330	dst_port = tb_port_at(xd->route, sw);
2331	nhi_port = tb_switch_find_port(tb->root_switch, TB_TYPE_NHI);
2332
2333	mutex_lock(&tb->lock);
2334
2335	/*
2336	 * When tunneling DMA paths the link should not enter CL states
2337	 * so disable them now.
2338	 */
2339	tb_disable_clx(sw);
2340
2341	tunnel = tb_tunnel_alloc_dma(tb, nhi_port, dst_port, transmit_path,
2342				     transmit_ring, receive_path, receive_ring);
2343	if (!tunnel) {
2344		ret = -ENOMEM;
2345		goto err_clx;
2346	}
2347
2348	if (tb_tunnel_activate(tunnel)) {
2349		tb_port_info(nhi_port,
2350			     "DMA tunnel activation failed, aborting\n");
2351		ret = -EIO;
2352		goto err_free;
2353	}
2354
2355	list_add_tail(&tunnel->list, &tcm->tunnel_list);
2356	mutex_unlock(&tb->lock);
2357	return 0;
2358
2359err_free:
2360	tb_tunnel_put(tunnel);
2361err_clx:
2362	tb_enable_clx(sw);
2363	mutex_unlock(&tb->lock);
2364
2365	return ret;
2366}
2367
2368static void __tb_disconnect_xdomain_paths(struct tb *tb, struct tb_xdomain *xd,
2369					  int transmit_path, int transmit_ring,
2370					  int receive_path, int receive_ring)
2371{
2372	struct tb_cm *tcm = tb_priv(tb);
2373	struct tb_port *nhi_port, *dst_port;
2374	struct tb_tunnel *tunnel, *n;
2375	struct tb_switch *sw;
2376
2377	sw = tb_to_switch(xd->dev.parent);
2378	dst_port = tb_port_at(xd->route, sw);
2379	nhi_port = tb_switch_find_port(tb->root_switch, TB_TYPE_NHI);
2380
2381	list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) {
2382		if (!tb_tunnel_is_dma(tunnel))
2383			continue;
2384		if (tunnel->src_port != nhi_port || tunnel->dst_port != dst_port)
2385			continue;
2386
2387		if (tb_tunnel_match_dma(tunnel, transmit_path, transmit_ring,
2388					receive_path, receive_ring))
2389			tb_deactivate_and_free_tunnel(tunnel);
2390	}
2391
2392	/*
2393	 * Try to re-enable CL states now, it is OK if this fails
2394	 * because we may still have another DMA tunnel active through
2395	 * the same host router USB4 downstream port.
2396	 */
2397	tb_enable_clx(sw);
2398}
2399
2400static int tb_disconnect_xdomain_paths(struct tb *tb, struct tb_xdomain *xd,
2401				       int transmit_path, int transmit_ring,
2402				       int receive_path, int receive_ring)
2403{
2404	if (!xd->is_unplugged) {
2405		mutex_lock(&tb->lock);
2406		__tb_disconnect_xdomain_paths(tb, xd, transmit_path,
2407					      transmit_ring, receive_path,
2408					      receive_ring);
2409		mutex_unlock(&tb->lock);
2410	}
2411	return 0;
2412}
2413
2414/* hotplug handling */
2415
2416/*
2417 * tb_handle_hotplug() - handle hotplug event
2418 *
2419 * Executes on tb->wq.
2420 */
2421static void tb_handle_hotplug(struct work_struct *work)
2422{
2423	struct tb_hotplug_event *ev = container_of(work, typeof(*ev), work.work);
2424	struct tb *tb = ev->tb;
2425	struct tb_cm *tcm = tb_priv(tb);
2426	struct tb_switch *sw;
2427	struct tb_port *port;
2428
2429	/* Bring the domain back from sleep if it was suspended */
2430	pm_runtime_get_sync(&tb->dev);
2431
2432	mutex_lock(&tb->lock);
2433	if (!tcm->hotplug_active)
2434		goto out; /* during init, suspend or shutdown */
2435
2436	sw = tb_switch_find_by_route(tb, ev->route);
2437	if (!sw) {
2438		tb_warn(tb,
2439			"hotplug event from non existent switch %llx:%x (unplug: %d)\n",
2440			ev->route, ev->port, ev->unplug);
2441		goto out;
2442	}
2443	if (ev->port > sw->config.max_port_number) {
2444		tb_warn(tb,
2445			"hotplug event from non existent port %llx:%x (unplug: %d)\n",
2446			ev->route, ev->port, ev->unplug);
2447		goto put_sw;
2448	}
2449	port = &sw->ports[ev->port];
2450	if (tb_is_upstream_port(port)) {
2451		tb_dbg(tb, "hotplug event for upstream port %llx:%x (unplug: %d)\n",
2452		       ev->route, ev->port, ev->unplug);
2453		goto put_sw;
2454	}
2455
2456	pm_runtime_get_sync(&sw->dev);
2457
2458	if (ev->unplug) {
2459		tb_retimer_remove_all(port);
2460
2461		if (tb_port_has_remote(port)) {
2462			tb_port_dbg(port, "switch unplugged\n");
2463			tb_sw_set_unplugged(port->remote->sw);
2464			tb_free_invalid_tunnels(tb);
2465			tb_remove_dp_resources(port->remote->sw);
2466			tb_switch_tmu_disable(port->remote->sw);
2467			tb_switch_unconfigure_link(port->remote->sw);
2468			tb_switch_set_link_width(port->remote->sw,
2469						 TB_LINK_WIDTH_SINGLE);
2470			tb_switch_remove(port->remote->sw);
2471			port->remote = NULL;
2472			if (port->dual_link_port)
2473				port->dual_link_port->remote = NULL;
2474			/* Maybe we can create another DP tunnel */
2475			tb_recalc_estimated_bandwidth(tb);
2476			tb_tunnel_dp(tb);
2477		} else if (port->xdomain) {
2478			struct tb_xdomain *xd = tb_xdomain_get(port->xdomain);
2479
2480			tb_port_dbg(port, "xdomain unplugged\n");
2481			/*
2482			 * Service drivers are unbound during
2483			 * tb_xdomain_remove() so setting XDomain as
2484			 * unplugged here prevents deadlock if they call
2485			 * tb_xdomain_disable_paths(). We will tear down
2486			 * all the tunnels below.
2487			 */
2488			xd->is_unplugged = true;
2489			tb_xdomain_remove(xd);
2490			port->xdomain = NULL;
2491			__tb_disconnect_xdomain_paths(tb, xd, -1, -1, -1, -1);
2492			tb_xdomain_put(xd);
2493			tb_port_unconfigure_xdomain(port);
2494		} else if (tb_port_is_dpout(port) || tb_port_is_dpin(port)) {
2495			tb_dp_resource_unavailable(tb, port, "adapter unplug");
2496		} else if (!port->port) {
2497			tb_sw_dbg(sw, "xHCI disconnect request\n");
2498			tb_switch_xhci_disconnect(sw);
2499		} else {
2500			tb_port_dbg(port,
2501				   "got unplug event for disconnected port, ignoring\n");
2502		}
2503	} else if (port->remote) {
2504		tb_port_dbg(port, "got plug event for connected port, ignoring\n");
2505	} else if (!port->port && sw->authorized) {
2506		tb_sw_dbg(sw, "xHCI connect request\n");
2507		tb_switch_xhci_connect(sw);
2508	} else {
2509		if (tb_port_is_null(port)) {
2510			tb_port_dbg(port, "hotplug: scanning\n");
2511			tb_scan_port(port);
2512			if (!port->remote)
2513				tb_port_dbg(port, "hotplug: no switch found\n");
2514		} else if (tb_port_is_dpout(port) || tb_port_is_dpin(port)) {
2515			tb_dp_resource_available(tb, port);
2516		}
2517	}
2518
2519	pm_runtime_mark_last_busy(&sw->dev);
2520	pm_runtime_put_autosuspend(&sw->dev);
2521
2522put_sw:
2523	tb_switch_put(sw);
2524out:
2525	mutex_unlock(&tb->lock);
2526
2527	pm_runtime_mark_last_busy(&tb->dev);
2528	pm_runtime_put_autosuspend(&tb->dev);
2529
2530	kfree(ev);
2531}
2532
2533static int tb_alloc_dp_bandwidth(struct tb_tunnel *tunnel, int *requested_up,
2534				 int *requested_down)
2535{
2536	int allocated_up, allocated_down, available_up, available_down, ret;
2537	int requested_up_corrected, requested_down_corrected, granularity;
2538	int max_up, max_down, max_up_rounded, max_down_rounded;
2539	struct tb_bandwidth_group *group;
2540	struct tb *tb = tunnel->tb;
2541	struct tb_port *in, *out;
2542	bool downstream;
2543
2544	ret = tb_tunnel_allocated_bandwidth(tunnel, &allocated_up, &allocated_down);
2545	if (ret)
2546		return ret;
2547
2548	in = tunnel->src_port;
2549	out = tunnel->dst_port;
2550
2551	tb_tunnel_dbg(tunnel, "bandwidth allocated currently %d/%d Mb/s\n",
2552		      allocated_up, allocated_down);
2553
2554	/*
2555	 * If we get rounded up request from graphics side, say HBR2 x 4
2556	 * that is 17500 instead of 17280 (this is because of the
2557	 * granularity), we allow it too. Here the graphics has already
2558	 * negotiated with the DPRX the maximum possible rates (which is
2559	 * 17280 in this case).
2560	 *
2561	 * Since the link cannot go higher than 17280 we use that in our
2562	 * calculations but the DP IN adapter Allocated BW write must be
2563	 * the same value (17500) otherwise the adapter will mark it as
2564	 * failed for graphics.
2565	 */
2566	ret = tb_tunnel_maximum_bandwidth(tunnel, &max_up, &max_down);
2567	if (ret)
2568		goto fail;
2569
2570	ret = usb4_dp_port_granularity(in);
2571	if (ret < 0)
2572		goto fail;
2573	granularity = ret;
2574
2575	max_up_rounded = roundup(max_up, granularity);
2576	max_down_rounded = roundup(max_down, granularity);
2577
2578	/*
2579	 * This will "fix" the request down to the maximum supported
2580	 * rate * lanes if it is at the maximum rounded up level.
2581	 */
2582	requested_up_corrected = *requested_up;
2583	if (requested_up_corrected == max_up_rounded)
2584		requested_up_corrected = max_up;
2585	else if (requested_up_corrected < 0)
2586		requested_up_corrected = 0;
2587	requested_down_corrected = *requested_down;
2588	if (requested_down_corrected == max_down_rounded)
2589		requested_down_corrected = max_down;
2590	else if (requested_down_corrected < 0)
2591		requested_down_corrected = 0;
2592
2593	tb_tunnel_dbg(tunnel, "corrected bandwidth request %d/%d Mb/s\n",
2594		      requested_up_corrected, requested_down_corrected);
2595
2596	if ((*requested_up >= 0 && requested_up_corrected > max_up_rounded) ||
2597	    (*requested_down >= 0 && requested_down_corrected > max_down_rounded)) {
2598		tb_tunnel_dbg(tunnel,
2599			      "bandwidth request too high (%d/%d Mb/s > %d/%d Mb/s)\n",
2600			      requested_up_corrected, requested_down_corrected,
2601			      max_up_rounded, max_down_rounded);
2602		ret = -ENOBUFS;
2603		goto fail;
2604	}
2605
2606	downstream = tb_tunnel_direction_downstream(tunnel);
2607	group = in->group;
2608
2609	if ((*requested_up >= 0 && requested_up_corrected <= allocated_up) ||
2610	    (*requested_down >= 0 && requested_down_corrected <= allocated_down)) {
2611		if (tunnel->bw_mode) {
2612			int reserved;
2613			/*
2614			 * If requested bandwidth is less or equal than
2615			 * what is currently allocated to that tunnel we
2616			 * simply change the reservation of the tunnel
2617			 * and add the released bandwidth for the group
2618			 * for the next 10s. Then we release it for
2619			 * others to use.
2620			 */
2621			if (downstream)
2622				reserved = allocated_down - *requested_down;
2623			else
2624				reserved = allocated_up - *requested_up;
2625
2626			if (reserved > 0) {
2627				group->reserved += reserved;
2628				tb_dbg(tb, "group %d reserved %d total %d Mb/s\n",
2629				       group->index, reserved, group->reserved);
2630
2631				/*
2632				 * If it was not already pending,
2633				 * schedule release now. If it is then
2634				 * postpone it for the next 10s (unless
2635				 * it is already running in which case
2636				 * the 10s already expired and we should
2637				 * give the reserved back to others).
2638				 */
2639				mod_delayed_work(system_percpu_wq, &group->release_work,
2640					msecs_to_jiffies(TB_RELEASE_BW_TIMEOUT));
2641			}
2642		}
2643
2644		ret = tb_tunnel_alloc_bandwidth(tunnel, requested_up,
2645						requested_down);
2646		if (ret)
2647			goto fail;
2648
2649		return 0;
2650	}
2651
2652	/*
2653	 * More bandwidth is requested. Release all the potential
2654	 * bandwidth from USB3 first.
2655	 */
2656	ret = tb_release_unused_usb3_bandwidth(tb, in, out);
2657	if (ret)
2658		goto fail;
2659
2660	/*
2661	 * Then go over all tunnels that cross the same USB4 ports (they
2662	 * are also in the same group but we use the same function here
2663	 * that we use with the normal bandwidth allocation).
2664	 */
2665	ret = tb_available_bandwidth(tb, in, out, &available_up, &available_down,
2666				     true);
2667	if (ret)
2668		goto reclaim;
2669
2670	tb_tunnel_dbg(tunnel, "bandwidth available for allocation %d/%d (+ %u reserved) Mb/s\n",
2671		      available_up, available_down, group->reserved);
2672
2673	if ((*requested_up >= 0 &&
2674		available_up + group->reserved >= requested_up_corrected) ||
2675	    (*requested_down >= 0 &&
2676		available_down + group->reserved >= requested_down_corrected)) {
2677		int released = 0;
2678
2679		/*
2680		 * If bandwidth on a link is >= asym_threshold
2681		 * transition the link to asymmetric.
2682		 */
2683		ret = tb_configure_asym(tb, in, out, *requested_up,
2684					*requested_down);
2685		if (ret) {
2686			tb_configure_sym(tb, in, out, true);
2687			goto fail;
2688		}
2689
2690		ret = tb_tunnel_alloc_bandwidth(tunnel, requested_up,
2691						requested_down);
2692		if (ret) {
2693			tb_tunnel_warn(tunnel, "failed to allocate bandwidth\n");
2694			tb_configure_sym(tb, in, out, true);
2695		}
2696
2697		if (downstream) {
2698			if (*requested_down > available_down)
2699				released = *requested_down - available_down;
2700		} else {
2701			if (*requested_up > available_up)
2702				released = *requested_up - available_up;
2703		}
2704		if (released) {
2705			group->reserved -= released;
2706			tb_dbg(tb, "group %d released %d total %d Mb/s\n",
2707			       group->index, released, group->reserved);
2708		}
2709	} else {
2710		ret = -ENOBUFS;
2711	}
2712
2713reclaim:
2714	tb_reclaim_usb3_bandwidth(tb, in, out);
2715fail:
2716	if (ret && ret != -ENODEV) {
2717		/*
2718		 * Write back the same allocated (so no change), this
2719		 * makes the DPTX request fail on graphics side.
2720		 */
2721		tb_tunnel_dbg(tunnel,
2722			      "failing the request by rewriting allocated %d/%d Mb/s\n",
2723			      allocated_up, allocated_down);
2724		tb_tunnel_alloc_bandwidth(tunnel, &allocated_up, &allocated_down);
2725		tb_tunnel_event(tb, TB_TUNNEL_NO_BANDWIDTH, TB_TUNNEL_DP, in, out);
2726	}
2727
2728	return ret;
2729}
2730
2731static void tb_handle_dp_bandwidth_request(struct work_struct *work)
2732{
2733	struct tb_hotplug_event *ev = container_of(work, typeof(*ev), work.work);
2734	int requested_bw, requested_up, requested_down, ret;
2735	struct tb_tunnel *tunnel;
2736	struct tb *tb = ev->tb;
2737	struct tb_cm *tcm = tb_priv(tb);
2738	struct tb_switch *sw;
2739	struct tb_port *in;
2740
2741	pm_runtime_get_sync(&tb->dev);
2742
2743	mutex_lock(&tb->lock);
2744	if (!tcm->hotplug_active)
2745		goto unlock;
2746
2747	sw = tb_switch_find_by_route(tb, ev->route);
2748	if (!sw) {
2749		tb_warn(tb, "bandwidth request from non-existent router %llx\n",
2750			ev->route);
2751		goto unlock;
2752	}
2753
2754	in = &sw->ports[ev->port];
2755	if (!tb_port_is_dpin(in)) {
2756		tb_port_warn(in, "bandwidth request to non-DP IN adapter\n");
2757		goto put_sw;
2758	}
2759
2760	tb_port_dbg(in, "handling bandwidth allocation request, retry %d\n", ev->retry);
2761
2762	tunnel = tb_find_tunnel(tb, TB_TUNNEL_DP, in, NULL);
2763	if (!tunnel) {
2764		tb_port_warn(in, "failed to find tunnel\n");
2765		goto put_sw;
2766	}
2767
2768	if (!usb4_dp_port_bandwidth_mode_enabled(in)) {
2769		if (tunnel->bw_mode) {
2770			/*
2771			 * Reset the tunnel back to use the legacy
2772			 * allocation.
2773			 */
2774			tunnel->bw_mode = false;
2775			tb_port_dbg(in, "DPTX disabled bandwidth allocation mode\n");
2776		} else {
2777			tb_port_warn(in, "bandwidth allocation mode not enabled\n");
2778		}
2779		goto put_sw;
2780	}
2781
2782	ret = usb4_dp_port_requested_bandwidth(in);
2783	if (ret < 0) {
2784		if (ret == -ENODATA) {
2785			/*
2786			 * There is no request active so this means the
2787			 * BW allocation mode was enabled from graphics
2788			 * side. At this point we know that the graphics
2789			 * driver has read the DPRX capabilities so we
2790			 * can offer better bandwidth estimation.
2791			 */
2792			tb_port_dbg(in, "DPTX enabled bandwidth allocation mode, updating estimated bandwidth\n");
2793			tb_recalc_estimated_bandwidth(tb);
2794		} else {
2795			tb_port_warn(in, "failed to read requested bandwidth\n");
2796		}
2797		goto put_sw;
2798	}
2799	requested_bw = ret;
2800
2801	tb_port_dbg(in, "requested bandwidth %d Mb/s\n", requested_bw);
2802
2803	if (tb_tunnel_direction_downstream(tunnel)) {
2804		requested_up = -1;
2805		requested_down = requested_bw;
2806	} else {
2807		requested_up = requested_bw;
2808		requested_down = -1;
2809	}
2810
2811	ret = tb_alloc_dp_bandwidth(tunnel, &requested_up, &requested_down);
2812	if (ret) {
2813		if (ret == -ENOBUFS) {
2814			tb_tunnel_warn(tunnel,
2815				       "not enough bandwidth available\n");
2816		} else if (ret == -ENOTCONN) {
2817			tb_tunnel_dbg(tunnel, "not active yet\n");
2818			/*
2819			 * We got bandwidth allocation request but the
2820			 * tunnel is not yet active. This means that
2821			 * tb_dp_tunnel_active() is not yet called for
2822			 * this tunnel. Allow it some time and retry
2823			 * this request a couple of times.
2824			 */
2825			if (ev->retry < TB_BW_ALLOC_RETRIES) {
2826				tb_tunnel_dbg(tunnel,
2827					      "retrying bandwidth allocation request\n");
2828				tb_queue_dp_bandwidth_request(tb, ev->route,
2829							      ev->port,
2830							      ev->retry + 1,
2831							      msecs_to_jiffies(50));
2832			} else {
2833				tb_tunnel_dbg(tunnel,
2834					      "run out of retries, failing the request");
2835			}
2836		} else {
2837			tb_tunnel_warn(tunnel,
2838				       "failed to change bandwidth allocation\n");
2839		}
2840	} else {
2841		tb_tunnel_dbg(tunnel,
2842			      "bandwidth allocation changed to %d/%d Mb/s\n",
2843			      requested_up, requested_down);
2844
2845		/* Update other clients about the allocation change */
2846		tb_recalc_estimated_bandwidth(tb);
2847	}
2848
2849put_sw:
2850	tb_switch_put(sw);
2851unlock:
2852	mutex_unlock(&tb->lock);
2853
2854	pm_runtime_mark_last_busy(&tb->dev);
2855	pm_runtime_put_autosuspend(&tb->dev);
2856
2857	kfree(ev);
2858}
2859
2860static void tb_queue_dp_bandwidth_request(struct tb *tb, u64 route, u8 port,
2861					  int retry, unsigned long delay)
2862{
2863	struct tb_hotplug_event *ev;
2864
2865	ev = kmalloc(sizeof(*ev), GFP_KERNEL);
2866	if (!ev)
2867		return;
2868
2869	ev->tb = tb;
2870	ev->route = route;
2871	ev->port = port;
2872	ev->retry = retry;
2873	INIT_DELAYED_WORK(&ev->work, tb_handle_dp_bandwidth_request);
2874	queue_delayed_work(tb->wq, &ev->work, delay);
2875}
2876
2877static void tb_handle_notification(struct tb *tb, u64 route,
2878				   const struct cfg_error_pkg *error)
2879{
2880
2881	switch (error->error) {
2882	case TB_CFG_ERROR_PCIE_WAKE:
2883	case TB_CFG_ERROR_DP_CON_CHANGE:
2884	case TB_CFG_ERROR_DPTX_DISCOVERY:
2885		if (tb_cfg_ack_notification(tb->ctl, route, error))
2886			tb_warn(tb, "could not ack notification on %llx\n",
2887				route);
2888		break;
2889
2890	case TB_CFG_ERROR_DP_BW:
2891		if (tb_cfg_ack_notification(tb->ctl, route, error))
2892			tb_warn(tb, "could not ack notification on %llx\n",
2893				route);
2894		tb_queue_dp_bandwidth_request(tb, route, error->port, 0, 0);
2895		break;
2896
2897	default:
2898		/* Ignore for now */
2899		break;
2900	}
2901}
2902
2903/*
2904 * tb_schedule_hotplug_handler() - callback function for the control channel
2905 *
2906 * Delegates to tb_handle_hotplug.
2907 */
2908static void tb_handle_event(struct tb *tb, enum tb_cfg_pkg_type type,
2909			    const void *buf, size_t size)
2910{
2911	const struct cfg_event_pkg *pkg = buf;
2912	u64 route = tb_cfg_get_route(&pkg->header);
2913
2914	switch (type) {
2915	case TB_CFG_PKG_ERROR:
2916		tb_handle_notification(tb, route, (const struct cfg_error_pkg *)buf);
2917		return;
2918	case TB_CFG_PKG_EVENT:
2919		break;
2920	default:
2921		tb_warn(tb, "unexpected event %#x, ignoring\n", type);
2922		return;
2923	}
2924
2925	if (tb_cfg_ack_plug(tb->ctl, route, pkg->port, pkg->unplug)) {
2926		tb_warn(tb, "could not ack plug event on %llx:%x\n", route,
2927			pkg->port);
2928	}
2929
2930	tb_queue_hotplug(tb, route, pkg->port, pkg->unplug);
2931}
2932
2933static void tb_stop(struct tb *tb)
2934{
2935	struct tb_cm *tcm = tb_priv(tb);
2936	struct tb_tunnel *tunnel;
2937	struct tb_tunnel *n;
2938
2939	cancel_delayed_work(&tcm->remove_work);
2940	/* tunnels are only present after everything has been initialized */
2941	list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) {
2942		/*
2943		 * DMA tunnels require the driver to be functional so we
2944		 * tear them down. Other protocol tunnels can be left
2945		 * intact.
2946		 */
2947		if (tb_tunnel_is_dma(tunnel))
2948			tb_tunnel_deactivate(tunnel);
2949		tb_tunnel_put(tunnel);
2950	}
2951	tb_switch_remove(tb->root_switch);
2952	tcm->hotplug_active = false; /* signal tb_handle_hotplug to quit */
2953}
2954
2955static void tb_deinit(struct tb *tb)
2956{
2957	struct tb_cm *tcm = tb_priv(tb);
2958	int i;
2959
2960	/* Cancel all the release bandwidth workers */
2961	for (i = 0; i < ARRAY_SIZE(tcm->groups); i++)
2962		cancel_delayed_work_sync(&tcm->groups[i].release_work);
2963}
2964
2965static int tb_scan_finalize_switch(struct device *dev, void *data)
2966{
2967	if (tb_is_switch(dev)) {
2968		struct tb_switch *sw = tb_to_switch(dev);
2969
2970		/*
2971		 * If we found that the switch was already setup by the
2972		 * boot firmware, mark it as authorized now before we
2973		 * send uevent to userspace.
2974		 */
2975		if (sw->boot)
2976			sw->authorized = 1;
2977
2978		dev_set_uevent_suppress(dev, false);
2979		kobject_uevent(&dev->kobj, KOBJ_ADD);
2980		device_for_each_child(dev, NULL, tb_scan_finalize_switch);
2981	}
2982
2983	return 0;
2984}
2985
2986static int tb_start(struct tb *tb, bool reset)
2987{
2988	struct tb_cm *tcm = tb_priv(tb);
2989	bool discover = true;
2990	int ret;
2991
2992	tb->root_switch = tb_switch_alloc(tb, &tb->dev, 0);
2993	if (IS_ERR(tb->root_switch))
2994		return PTR_ERR(tb->root_switch);
2995
2996	/*
2997	 * ICM firmware upgrade needs running firmware and in native
2998	 * mode that is not available so disable firmware upgrade of the
2999	 * root switch.
3000	 *
3001	 * However, USB4 routers support NVM firmware upgrade if they
3002	 * implement the necessary router operations.
3003	 */
3004	tb->root_switch->no_nvm_upgrade = !tb_switch_is_usb4(tb->root_switch);
3005	/* All USB4 routers support runtime PM */
3006	tb->root_switch->rpm = tb_switch_is_usb4(tb->root_switch);
3007
3008	ret = tb_switch_configure(tb->root_switch);
3009	if (ret) {
3010		tb_switch_put(tb->root_switch);
3011		return ret;
3012	}
3013
3014	/* Announce the switch to the world */
3015	ret = tb_switch_add(tb->root_switch);
3016	if (ret) {
3017		tb_switch_put(tb->root_switch);
3018		return ret;
3019	}
3020
3021	/*
3022	 * To support highest CLx state, we set host router's TMU to
3023	 * Normal mode.
3024	 */
3025	tb_switch_tmu_configure(tb->root_switch, TB_SWITCH_TMU_MODE_LOWRES);
3026	/* Enable TMU if it is off */
3027	tb_switch_tmu_enable(tb->root_switch);
3028
3029	/*
3030	 * Boot firmware might have created tunnels of its own. Since we
3031	 * cannot be sure they are usable for us, tear them down and
3032	 * reset the ports to handle it as new hotplug for USB4 v1
3033	 * routers (for USB4 v2 and beyond we already do host reset).
3034	 */
3035	if (reset && tb_switch_is_usb4(tb->root_switch)) {
3036		discover = false;
3037		if (usb4_switch_version(tb->root_switch) == 1)
3038			tb_switch_reset(tb->root_switch);
3039	}
3040
3041	if (discover) {
3042		/* Full scan to discover devices added before the driver was loaded. */
3043		tb_scan_switch(tb->root_switch);
3044		/* Find out tunnels created by the boot firmware */
3045		tb_discover_tunnels(tb);
3046		/* Add DP resources from the DP tunnels created by the boot firmware */
3047		tb_discover_dp_resources(tb);
3048	}
3049
3050	/*
3051	 * If the boot firmware did not create USB 3.x tunnels create them
3052	 * now for the whole topology.
3053	 */
3054	tb_create_usb3_tunnels(tb->root_switch);
3055	/* Add DP IN resources for the root switch */
3056	tb_add_dp_resources(tb->root_switch);
3057	tb_switch_enter_redrive(tb->root_switch);
3058	/* Make the discovered switches available to the userspace */
3059	device_for_each_child(&tb->root_switch->dev, NULL,
3060			      tb_scan_finalize_switch);
3061
3062	/* Allow tb_handle_hotplug to progress events */
3063	tcm->hotplug_active = true;
3064	return 0;
3065}
3066
3067static int tb_suspend_noirq(struct tb *tb)
3068{
3069	struct tb_cm *tcm = tb_priv(tb);
3070
3071	tb_dbg(tb, "suspending...\n");
3072	tb_disconnect_and_release_dp(tb);
3073	tb_switch_exit_redrive(tb->root_switch);
3074	tb_switch_suspend(tb->root_switch, false);
3075	tcm->hotplug_active = false; /* signal tb_handle_hotplug to quit */
3076	tb_dbg(tb, "suspend finished\n");
3077
3078	return 0;
3079}
3080
3081static void tb_restore_children(struct tb_switch *sw)
3082{
3083	struct tb_port *port;
3084
3085	/* No need to restore if the router is already unplugged */
3086	if (sw->is_unplugged)
3087		return;
3088
3089	if (tb_enable_clx(sw))
3090		tb_sw_warn(sw, "failed to re-enable CL states\n");
3091
3092	if (tb_enable_tmu(sw))
3093		tb_sw_warn(sw, "failed to restore TMU configuration\n");
3094
3095	tb_switch_configuration_valid(sw);
3096
3097	tb_switch_for_each_port(sw, port) {
3098		if (!tb_port_has_remote(port) && !port->xdomain)
3099			continue;
3100
3101		if (port->remote) {
3102			tb_switch_set_link_width(port->remote->sw,
3103						 port->remote->sw->link_width);
3104			tb_switch_configure_link(port->remote->sw);
3105
3106			tb_restore_children(port->remote->sw);
3107		} else if (port->xdomain) {
3108			tb_port_configure_xdomain(port, port->xdomain);
3109		}
3110	}
3111}
3112
3113static int tb_resume_noirq(struct tb *tb)
3114{
3115	struct tb_cm *tcm = tb_priv(tb);
3116	struct tb_tunnel *tunnel, *n;
3117	unsigned int usb3_delay = 0;
3118	LIST_HEAD(tunnels);
3119
3120	tb_dbg(tb, "resuming...\n");
3121
3122	/*
3123	 * For non-USB4 hosts (Apple systems) remove any PCIe devices
3124	 * the firmware might have setup.
3125	 */
3126	if (!tb_switch_is_usb4(tb->root_switch))
3127		tb_switch_reset(tb->root_switch);
3128
3129	tb_switch_resume(tb->root_switch, false);
3130	tb_free_invalid_tunnels(tb);
3131	tb_free_unplugged_children(tb->root_switch);
3132	tb_restore_children(tb->root_switch);
3133
3134	/*
3135	 * If we get here from suspend to disk the boot firmware or the
3136	 * restore kernel might have created tunnels of its own. Since
3137	 * we cannot be sure they are usable for us we find and tear
3138	 * them down.
3139	 */
3140	tb_switch_discover_tunnels(tb->root_switch, &tunnels, false);
3141	list_for_each_entry_safe_reverse(tunnel, n, &tunnels, list) {
3142		if (tb_tunnel_is_usb3(tunnel))
3143			usb3_delay = 500;
3144		tb_tunnel_deactivate(tunnel);
3145		tb_tunnel_put(tunnel);
3146	}
3147
3148	/* Re-create our tunnels now */
3149	list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) {
3150		/* USB3 requires delay before it can be re-activated */
3151		if (tb_tunnel_is_usb3(tunnel)) {
3152			msleep(usb3_delay);
3153			/* Only need to do it once */
3154			usb3_delay = 0;
3155		}
3156		tb_tunnel_activate(tunnel);
3157	}
3158	if (!list_empty(&tcm->tunnel_list)) {
3159		/*
3160		 * the pcie links need some time to get going.
3161		 * 100ms works for me...
3162		 */
3163		tb_dbg(tb, "tunnels restarted, sleeping for 100ms\n");
3164		msleep(100);
3165	}
3166	tb_switch_enter_redrive(tb->root_switch);
3167	 /* Allow tb_handle_hotplug to progress events */
3168	tcm->hotplug_active = true;
3169	tb_dbg(tb, "resume finished\n");
3170
3171	return 0;
3172}
3173
3174static int tb_free_unplugged_xdomains(struct tb_switch *sw)
3175{
3176	struct tb_port *port;
3177	int ret = 0;
3178
3179	tb_switch_for_each_port(sw, port) {
3180		if (tb_is_upstream_port(port))
3181			continue;
3182		if (port->xdomain && port->xdomain->is_unplugged) {
3183			tb_retimer_remove_all(port);
3184			tb_xdomain_remove(port->xdomain);
3185			tb_port_unconfigure_xdomain(port);
3186			port->xdomain = NULL;
3187			ret++;
3188		} else if (port->remote) {
3189			ret += tb_free_unplugged_xdomains(port->remote->sw);
3190		}
3191	}
3192
3193	return ret;
3194}
3195
3196static int tb_freeze_noirq(struct tb *tb)
3197{
3198	struct tb_cm *tcm = tb_priv(tb);
3199
3200	tcm->hotplug_active = false;
3201	return 0;
3202}
3203
3204static int tb_thaw_noirq(struct tb *tb)
3205{
3206	struct tb_cm *tcm = tb_priv(tb);
3207
3208	tcm->hotplug_active = true;
3209	return 0;
3210}
3211
3212static void tb_complete(struct tb *tb)
3213{
3214	/*
3215	 * Release any unplugged XDomains and if there is a case where
3216	 * another domain is swapped in place of unplugged XDomain we
3217	 * need to run another rescan.
3218	 */
3219	mutex_lock(&tb->lock);
3220	if (tb_free_unplugged_xdomains(tb->root_switch))
3221		tb_scan_switch(tb->root_switch);
3222	mutex_unlock(&tb->lock);
3223}
3224
3225static int tb_runtime_suspend(struct tb *tb)
3226{
3227	struct tb_cm *tcm = tb_priv(tb);
3228
3229	mutex_lock(&tb->lock);
3230	/*
3231	 * The below call only releases DP resources to allow exiting and
3232	 * re-entering redrive mode.
3233	 */
3234	tb_disconnect_and_release_dp(tb);
3235	tb_switch_exit_redrive(tb->root_switch);
3236	tb_switch_suspend(tb->root_switch, true);
3237	tcm->hotplug_active = false;
3238	mutex_unlock(&tb->lock);
3239
3240	return 0;
3241}
3242
3243static void tb_remove_work(struct work_struct *work)
3244{
3245	struct tb_cm *tcm = container_of(work, struct tb_cm, remove_work.work);
3246	struct tb *tb = tcm_to_tb(tcm);
3247
3248	mutex_lock(&tb->lock);
3249	if (tb->root_switch) {
3250		tb_free_unplugged_children(tb->root_switch);
3251		tb_free_unplugged_xdomains(tb->root_switch);
3252	}
3253	mutex_unlock(&tb->lock);
3254}
3255
3256static int tb_runtime_resume(struct tb *tb)
3257{
3258	struct tb_cm *tcm = tb_priv(tb);
3259	struct tb_tunnel *tunnel, *n;
3260
3261	mutex_lock(&tb->lock);
3262	tb_switch_resume(tb->root_switch, true);
3263	tb_free_invalid_tunnels(tb);
3264	tb_restore_children(tb->root_switch);
3265	list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list)
3266		tb_tunnel_activate(tunnel);
3267	tb_switch_enter_redrive(tb->root_switch);
3268	tcm->hotplug_active = true;
3269	mutex_unlock(&tb->lock);
3270
3271	/*
3272	 * Schedule cleanup of any unplugged devices. Run this in a
3273	 * separate thread to avoid possible deadlock if the device
3274	 * removal runtime resumes the unplugged device.
3275	 */
3276	queue_delayed_work(tb->wq, &tcm->remove_work, msecs_to_jiffies(50));
3277	return 0;
3278}
3279
3280static const struct tb_cm_ops tb_cm_ops = {
3281	.start = tb_start,
3282	.stop = tb_stop,
3283	.deinit = tb_deinit,
3284	.suspend_noirq = tb_suspend_noirq,
3285	.resume_noirq = tb_resume_noirq,
3286	.freeze_noirq = tb_freeze_noirq,
3287	.thaw_noirq = tb_thaw_noirq,
3288	.complete = tb_complete,
3289	.runtime_suspend = tb_runtime_suspend,
3290	.runtime_resume = tb_runtime_resume,
3291	.handle_event = tb_handle_event,
3292	.disapprove_switch = tb_disconnect_pci,
3293	.approve_switch = tb_tunnel_pci,
3294	.approve_xdomain_paths = tb_approve_xdomain_paths,
3295	.disconnect_xdomain_paths = tb_disconnect_xdomain_paths,
3296};
3297
3298/*
3299 * During suspend the Thunderbolt controller is reset and all PCIe
3300 * tunnels are lost. The NHI driver will try to reestablish all tunnels
3301 * during resume. This adds device links between the tunneled PCIe
3302 * downstream ports and the NHI so that the device core will make sure
3303 * NHI is resumed first before the rest.
3304 */
3305static bool tb_apple_add_links(struct tb_nhi *nhi)
3306{
3307	struct pci_dev *upstream, *pdev;
3308	bool ret;
3309
3310	if (!x86_apple_machine)
3311		return false;
3312
3313	switch (nhi->pdev->device) {
3314	case PCI_DEVICE_ID_INTEL_LIGHT_RIDGE:
3315	case PCI_DEVICE_ID_INTEL_CACTUS_RIDGE_4C:
3316	case PCI_DEVICE_ID_INTEL_FALCON_RIDGE_2C_NHI:
3317	case PCI_DEVICE_ID_INTEL_FALCON_RIDGE_4C_NHI:
3318		break;
3319	default:
3320		return false;
3321	}
3322
3323	upstream = pci_upstream_bridge(nhi->pdev);
3324	while (upstream) {
3325		if (!pci_is_pcie(upstream))
3326			return false;
3327		if (pci_pcie_type(upstream) == PCI_EXP_TYPE_UPSTREAM)
3328			break;
3329		upstream = pci_upstream_bridge(upstream);
3330	}
3331
3332	if (!upstream)
3333		return false;
3334
3335	/*
3336	 * For each hotplug downstream port, create add device link
3337	 * back to NHI so that PCIe tunnels can be re-established after
3338	 * sleep.
3339	 */
3340	ret = false;
3341	for_each_pci_bridge(pdev, upstream->subordinate) {
3342		const struct device_link *link;
3343
3344		if (!pci_is_pcie(pdev))
3345			continue;
3346		if (pci_pcie_type(pdev) != PCI_EXP_TYPE_DOWNSTREAM ||
3347		    !pdev->is_pciehp)
3348			continue;
3349
3350		link = device_link_add(&pdev->dev, &nhi->pdev->dev,
3351				       DL_FLAG_AUTOREMOVE_SUPPLIER |
3352				       DL_FLAG_PM_RUNTIME);
3353		if (link) {
3354			dev_dbg(&nhi->pdev->dev, "created link from %s\n",
3355				dev_name(&pdev->dev));
3356			ret = true;
3357		} else {
3358			dev_warn(&nhi->pdev->dev, "device link creation from %s failed\n",
3359				 dev_name(&pdev->dev));
3360		}
3361	}
3362
3363	return ret;
3364}
3365
3366struct tb *tb_probe(struct tb_nhi *nhi)
3367{
3368	struct tb_cm *tcm;
3369	struct tb *tb;
3370
3371	tb = tb_domain_alloc(nhi, TB_TIMEOUT, sizeof(*tcm));
3372	if (!tb)
3373		return NULL;
3374
3375	if (tb_acpi_may_tunnel_pcie())
3376		tb->security_level = TB_SECURITY_USER;
3377	else
3378		tb->security_level = TB_SECURITY_NOPCIE;
3379
3380	tb->cm_ops = &tb_cm_ops;
3381
3382	tcm = tb_priv(tb);
3383	INIT_LIST_HEAD(&tcm->tunnel_list);
3384	INIT_LIST_HEAD(&tcm->dp_resources);
3385	INIT_DELAYED_WORK(&tcm->remove_work, tb_remove_work);
3386	tb_init_bandwidth_groups(tcm);
3387
3388	tb_dbg(tb, "using software connection manager\n");
3389
3390	/*
3391	 * Device links are needed to make sure we establish tunnels
3392	 * before the PCIe/USB stack is resumed so complain here if we
3393	 * found them missing.
3394	 */
3395	if (!tb_apple_add_links(nhi) && !tb_acpi_add_links(nhi))
3396		tb_warn(tb, "device links to tunneled native ports are missing!\n");
3397
3398	return tb;
3399}