drivers/thunderbolt/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
  21 /**
  22  * struct tb_cm - Simple Thunderbolt connection manager
  23  * @tunnel_list: List of active tunnels
  24  * @dp_resources: List of available DP resources for DP tunneling
  25  * @hotplug_active: tb_handle_hotplug will stop progressing plug
  26  *                  events and exit if this is not set (it needs to
  27  *                  acquire the lock one more time). Used to drain wq
  28  *                  after cfg has been paused.
  29  * @remove_work: Work used to remove any unplugged routers after
  30  *               runtime resume
  31  */
  32 struct tb_cm {
  33         struct list_head tunnel_list;
  34         struct list_head dp_resources;
  35         bool hotplug_active;
  36         struct delayed_work remove_work;
  37 };
  38
  39 static inline struct tb *tcm_to_tb(struct tb_cm *tcm)
  40 {
  41         return ((void *)tcm - sizeof(struct tb));
  42 }
  43
  44 struct tb_hotplug_event {
  45         struct work_struct work;
  46         struct tb *tb;
  47         u64 route;
  48         u8 port;
  49         bool unplug;
  50 };
  51
  52 static void tb_handle_hotplug(struct work_struct *work);
  53
  54 static void tb_queue_hotplug(struct tb *tb, u64 route, u8 port, bool unplug)
  55 {
  56         struct tb_hotplug_event *ev;
  57
  58         ev = kmalloc(sizeof(*ev), GFP_KERNEL);
  59         if (!ev)
  60                 return;
  61
  62         ev->tb = tb;
  63         ev->route = route;
  64         ev->port = port;
  65         ev->unplug = unplug;
  66         INIT_WORK(&ev->work, tb_handle_hotplug);
  67         queue_work(tb->wq, &ev->work);
  68 }
  69
  70 /* enumeration & hot plug handling */
  71
  72 static void tb_add_dp_resources(struct tb_switch *sw)
  73 {
  74         struct tb_cm *tcm = tb_priv(sw->tb);
  75         struct tb_port *port;
  76
  77         tb_switch_for_each_port(sw, port) {
  78                 if (!tb_port_is_dpin(port))
  79                         continue;
  80
  81                 if (!tb_switch_query_dp_resource(sw, port))
  82                         continue;
  83
  84                 list_add_tail(&port->list, &tcm->dp_resources);
  85                 tb_port_dbg(port, "DP IN resource available\n");
  86         }
  87 }
  88
  89 static void tb_remove_dp_resources(struct tb_switch *sw)
  90 {
  91         struct tb_cm *tcm = tb_priv(sw->tb);
  92         struct tb_port *port, *tmp;
  93
  94         /* Clear children resources first */
  95         tb_switch_for_each_port(sw, port) {
  96                 if (tb_port_has_remote(port))
  97                         tb_remove_dp_resources(port->remote->sw);
  98         }
  99
 100         list_for_each_entry_safe(port, tmp, &tcm->dp_resources, list) {
 101                 if (port->sw == sw) {
 102                         tb_port_dbg(port, "DP OUT resource unavailable\n");
 103                         list_del_init(&port->list);
 104                 }
 105         }
 106 }
 107
 108 static void tb_discover_tunnels(struct tb_switch *sw)
 109 {
 110         struct tb *tb = sw->tb;
 111         struct tb_cm *tcm = tb_priv(tb);
 112         struct tb_port *port;
 113
 114         tb_switch_for_each_port(sw, port) {
 115                 struct tb_tunnel *tunnel = NULL;
 116
 117                 switch (port->config.type) {
 118                 case TB_TYPE_DP_HDMI_IN:
 119                         tunnel = tb_tunnel_discover_dp(tb, port);
 120                         break;
 121
 122                 case TB_TYPE_PCIE_DOWN:
 123                         tunnel = tb_tunnel_discover_pci(tb, port);
 124                         break;
 125
 126                 case TB_TYPE_USB3_DOWN:
 127                         tunnel = tb_tunnel_discover_usb3(tb, port);
 128                         break;
 129
 130                 default:
 131                         break;
 132                 }
 133
 134                 if (!tunnel)
 135                         continue;
 136
 137                 if (tb_tunnel_is_pci(tunnel)) {
 138                         struct tb_switch *parent = tunnel->dst_port->sw;
 139
 140                         while (parent != tunnel->src_port->sw) {
 141                                 parent->boot = true;
 142                                 parent = tb_switch_parent(parent);
 143                         }
 144                 } else if (tb_tunnel_is_dp(tunnel)) {
 145                         /* Keep the domain from powering down */
 146                         pm_runtime_get_sync(&tunnel->src_port->sw->dev);
 147                         pm_runtime_get_sync(&tunnel->dst_port->sw->dev);
 148                 }
 149
 150                 list_add_tail(&tunnel->list, &tcm->tunnel_list);
 151         }
 152
 153         tb_switch_for_each_port(sw, port) {
 154                 if (tb_port_has_remote(port))
 155                         tb_discover_tunnels(port->remote->sw);
 156         }
 157 }
 158
 159 static int tb_port_configure_xdomain(struct tb_port *port)
 160 {
 161         /*
 162          * XDomain paths currently only support single lane so we must
 163          * disable the other lane according to USB4 spec.
 164          */
 165         tb_port_disable(port->dual_link_port);
 166
 167         if (tb_switch_is_usb4(port->sw))
 168                 return usb4_port_configure_xdomain(port);
 169         return tb_lc_configure_xdomain(port);
 170 }
 171
 172 static void tb_port_unconfigure_xdomain(struct tb_port *port)
 173 {
 174         if (tb_switch_is_usb4(port->sw))
 175                 usb4_port_unconfigure_xdomain(port);
 176         else
 177                 tb_lc_unconfigure_xdomain(port);
 178
 179         tb_port_enable(port->dual_link_port);
 180 }
 181
 182 static void tb_scan_xdomain(struct tb_port *port)
 183 {
 184         struct tb_switch *sw = port->sw;
 185         struct tb *tb = sw->tb;
 186         struct tb_xdomain *xd;
 187         u64 route;
 188
 189         if (!tb_is_xdomain_enabled())
 190                 return;
 191
 192         route = tb_downstream_route(port);
 193         xd = tb_xdomain_find_by_route(tb, route);
 194         if (xd) {
 195                 tb_xdomain_put(xd);
 196                 return;
 197         }
 198
 199         xd = tb_xdomain_alloc(tb, &sw->dev, route, tb->root_switch->uuid,
 200                               NULL);
 201         if (xd) {
 202                 tb_port_at(route, sw)->xdomain = xd;
 203                 tb_port_configure_xdomain(port);
 204                 tb_xdomain_add(xd);
 205         }
 206 }
 207
 208 static int tb_enable_tmu(struct tb_switch *sw)
 209 {
 210         int ret;
 211
 212         /* If it is already enabled in correct mode, don't touch it */
 213         if (tb_switch_tmu_is_enabled(sw))
 214                 return 0;
 215
 216         ret = tb_switch_tmu_disable(sw);
 217         if (ret)
 218                 return ret;
 219
 220         ret = tb_switch_tmu_post_time(sw);
 221         if (ret)
 222                 return ret;
 223
 224         return tb_switch_tmu_enable(sw);
 225 }
 226
 227 /**
 228  * tb_find_unused_port() - return the first inactive port on @sw
 229  * @sw: Switch to find the port on
 230  * @type: Port type to look for
 231  */
 232 static struct tb_port *tb_find_unused_port(struct tb_switch *sw,
 233                                            enum tb_port_type type)
 234 {
 235         struct tb_port *port;
 236
 237         tb_switch_for_each_port(sw, port) {
 238                 if (tb_is_upstream_port(port))
 239                         continue;
 240                 if (port->config.type != type)
 241                         continue;
 242                 if (!port->cap_adap)
 243                         continue;
 244                 if (tb_port_is_enabled(port))
 245                         continue;
 246                 return port;
 247         }
 248         return NULL;
 249 }
 250
 251 static struct tb_port *tb_find_usb3_down(struct tb_switch *sw,
 252                                          const struct tb_port *port)
 253 {
 254         struct tb_port *down;
 255
 256         down = usb4_switch_map_usb3_down(sw, port);
 257         if (down && !tb_usb3_port_is_enabled(down))
 258                 return down;
 259         return NULL;
 260 }
 261
 262 static struct tb_tunnel *tb_find_tunnel(struct tb *tb, enum tb_tunnel_type type,
 263                                         struct tb_port *src_port,
 264                                         struct tb_port *dst_port)
 265 {
 266         struct tb_cm *tcm = tb_priv(tb);
 267         struct tb_tunnel *tunnel;
 268
 269         list_for_each_entry(tunnel, &tcm->tunnel_list, list) {
 270                 if (tunnel->type == type &&
 271                     ((src_port && src_port == tunnel->src_port) ||
 272                      (dst_port && dst_port == tunnel->dst_port))) {
 273                         return tunnel;
 274                 }
 275         }
 276
 277         return NULL;
 278 }
 279
 280 static struct tb_tunnel *tb_find_first_usb3_tunnel(struct tb *tb,
 281                                                    struct tb_port *src_port,
 282                                                    struct tb_port *dst_port)
 283 {
 284         struct tb_port *port, *usb3_down;
 285         struct tb_switch *sw;
 286
 287         /* Pick the router that is deepest in the topology */
 288         if (dst_port->sw->config.depth > src_port->sw->config.depth)
 289                 sw = dst_port->sw;
 290         else
 291                 sw = src_port->sw;
 292
 293         /* Can't be the host router */
 294         if (sw == tb->root_switch)
 295                 return NULL;
 296
 297         /* Find the downstream USB4 port that leads to this router */
 298         port = tb_port_at(tb_route(sw), tb->root_switch);
 299         /* Find the corresponding host router USB3 downstream port */
 300         usb3_down = usb4_switch_map_usb3_down(tb->root_switch, port);
 301         if (!usb3_down)
 302                 return NULL;
 303
 304         return tb_find_tunnel(tb, TB_TUNNEL_USB3, usb3_down, NULL);
 305 }
 306
 307 static int tb_available_bandwidth(struct tb *tb, struct tb_port *src_port,
 308         struct tb_port *dst_port, int *available_up, int *available_down)
 309 {
 310         int usb3_consumed_up, usb3_consumed_down, ret;
 311         struct tb_cm *tcm = tb_priv(tb);
 312         struct tb_tunnel *tunnel;
 313         struct tb_port *port;
 314
 315         tb_port_dbg(dst_port, "calculating available bandwidth\n");
 316
 317         tunnel = tb_find_first_usb3_tunnel(tb, src_port, dst_port);
 318         if (tunnel) {
 319                 ret = tb_tunnel_consumed_bandwidth(tunnel, &usb3_consumed_up,
 320                                                    &usb3_consumed_down);
 321                 if (ret)
 322                         return ret;
 323         } else {
 324                 usb3_consumed_up = 0;
 325                 usb3_consumed_down = 0;
 326         }
 327
 328         *available_up = *available_down = 40000;
 329
 330         /* Find the minimum available bandwidth over all links */
 331         tb_for_each_port_on_path(src_port, dst_port, port) {
 332                 int link_speed, link_width, up_bw, down_bw;
 333
 334                 if (!tb_port_is_null(port))
 335                         continue;
 336
 337                 if (tb_is_upstream_port(port)) {
 338                         link_speed = port->sw->link_speed;
 339                 } else {
 340                         link_speed = tb_port_get_link_speed(port);
 341                         if (link_speed < 0)
 342                                 return link_speed;
 343                 }
 344
 345                 link_width = port->bonded ? 2 : 1;
 346
 347                 up_bw = link_speed * link_width * 1000; /* Mb/s */
 348                 /* Leave 10% guard band */
 349                 up_bw -= up_bw / 10;
 350                 down_bw = up_bw;
 351
 352                 tb_port_dbg(port, "link total bandwidth %d Mb/s\n", up_bw);
 353
 354                 /*
 355                  * Find all DP tunnels that cross the port and reduce
 356                  * their consumed bandwidth from the available.
 357                  */
 358                 list_for_each_entry(tunnel, &tcm->tunnel_list, list) {
 359                         int dp_consumed_up, dp_consumed_down;
 360
 361                         if (!tb_tunnel_is_dp(tunnel))
 362                                 continue;
 363
 364                         if (!tb_tunnel_port_on_path(tunnel, port))
 365                                 continue;
 366
 367                         ret = tb_tunnel_consumed_bandwidth(tunnel,
 368                                                            &dp_consumed_up,
 369                                                            &dp_consumed_down);
 370                         if (ret)
 371                                 return ret;
 372
 373                         up_bw -= dp_consumed_up;
 374                         down_bw -= dp_consumed_down;
 375                 }
 376
 377                 /*
 378                  * If USB3 is tunneled from the host router down to the
 379                  * branch leading to port we need to take USB3 consumed
 380                  * bandwidth into account regardless whether it actually
 381                  * crosses the port.
 382                  */
 383                 up_bw -= usb3_consumed_up;
 384                 down_bw -= usb3_consumed_down;
 385
 386                 if (up_bw < *available_up)
 387                         *available_up = up_bw;
 388                 if (down_bw < *available_down)
 389                         *available_down = down_bw;
 390         }
 391
 392         if (*available_up < 0)
 393                 *available_up = 0;
 394         if (*available_down < 0)
 395                 *available_down = 0;
 396
 397         return 0;
 398 }
 399
 400 static int tb_release_unused_usb3_bandwidth(struct tb *tb,
 401                                             struct tb_port *src_port,
 402                                             struct tb_port *dst_port)
 403 {
 404         struct tb_tunnel *tunnel;
 405
 406         tunnel = tb_find_first_usb3_tunnel(tb, src_port, dst_port);
 407         return tunnel ? tb_tunnel_release_unused_bandwidth(tunnel) : 0;
 408 }
 409
 410 static void tb_reclaim_usb3_bandwidth(struct tb *tb, struct tb_port *src_port,
 411                                       struct tb_port *dst_port)
 412 {
 413         int ret, available_up, available_down;
 414         struct tb_tunnel *tunnel;
 415
 416         tunnel = tb_find_first_usb3_tunnel(tb, src_port, dst_port);
 417         if (!tunnel)
 418                 return;
 419
 420         tb_dbg(tb, "reclaiming unused bandwidth for USB3\n");
 421
 422         /*
 423          * Calculate available bandwidth for the first hop USB3 tunnel.
 424          * That determines the whole USB3 bandwidth for this branch.
 425          */
 426         ret = tb_available_bandwidth(tb, tunnel->src_port, tunnel->dst_port,
 427                                      &available_up, &available_down);
 428         if (ret) {
 429                 tb_warn(tb, "failed to calculate available bandwidth\n");
 430                 return;
 431         }
 432
 433         tb_dbg(tb, "available bandwidth for USB3 %d/%d Mb/s\n",
 434                available_up, available_down);
 435
 436         tb_tunnel_reclaim_available_bandwidth(tunnel, &available_up, &available_down);
 437 }
 438
 439 static int tb_tunnel_usb3(struct tb *tb, struct tb_switch *sw)
 440 {
 441         struct tb_switch *parent = tb_switch_parent(sw);
 442         int ret, available_up, available_down;
 443         struct tb_port *up, *down, *port;
 444         struct tb_cm *tcm = tb_priv(tb);
 445         struct tb_tunnel *tunnel;
 446
 447         if (!tb_acpi_may_tunnel_usb3()) {
 448                 tb_dbg(tb, "USB3 tunneling disabled, not creating tunnel\n");
 449                 return 0;
 450         }
 451
 452         up = tb_switch_find_port(sw, TB_TYPE_USB3_UP);
 453         if (!up)
 454                 return 0;
 455
 456         if (!sw->link_usb4)
 457                 return 0;
 458
 459         /*
 460          * Look up available down port. Since we are chaining it should
 461          * be found right above this switch.
 462          */
 463         port = tb_port_at(tb_route(sw), parent);
 464         down = tb_find_usb3_down(parent, port);
 465         if (!down)
 466                 return 0;
 467
 468         if (tb_route(parent)) {
 469                 struct tb_port *parent_up;
 470                 /*
 471                  * Check first that the parent switch has its upstream USB3
 472                  * port enabled. Otherwise the chain is not complete and
 473                  * there is no point setting up a new tunnel.
 474                  */
 475                 parent_up = tb_switch_find_port(parent, TB_TYPE_USB3_UP);
 476                 if (!parent_up || !tb_port_is_enabled(parent_up))
 477                         return 0;
 478
 479                 /* Make all unused bandwidth available for the new tunnel */
 480                 ret = tb_release_unused_usb3_bandwidth(tb, down, up);
 481                 if (ret)
 482                         return ret;
 483         }
 484
 485         ret = tb_available_bandwidth(tb, down, up, &available_up,
 486                                      &available_down);
 487         if (ret)
 488                 goto err_reclaim;
 489
 490         tb_port_dbg(up, "available bandwidth for new USB3 tunnel %d/%d Mb/s\n",
 491                     available_up, available_down);
 492
 493         tunnel = tb_tunnel_alloc_usb3(tb, up, down, available_up,
 494                                       available_down);
 495         if (!tunnel) {
 496                 ret = -ENOMEM;
 497                 goto err_reclaim;
 498         }
 499
 500         if (tb_tunnel_activate(tunnel)) {
 501                 tb_port_info(up,
 502                              "USB3 tunnel activation failed, aborting\n");
 503                 ret = -EIO;
 504                 goto err_free;
 505         }
 506
 507         list_add_tail(&tunnel->list, &tcm->tunnel_list);
 508         if (tb_route(parent))
 509                 tb_reclaim_usb3_bandwidth(tb, down, up);
 510
 511         return 0;
 512
 513 err_free:
 514         tb_tunnel_free(tunnel);
 515 err_reclaim:
 516         if (tb_route(parent))
 517                 tb_reclaim_usb3_bandwidth(tb, down, up);
 518
 519         return ret;
 520 }
 521
 522 static int tb_create_usb3_tunnels(struct tb_switch *sw)
 523 {
 524         struct tb_port *port;
 525         int ret;
 526
 527         if (!tb_acpi_may_tunnel_usb3())
 528                 return 0;
 529
 530         if (tb_route(sw)) {
 531                 ret = tb_tunnel_usb3(sw->tb, sw);
 532                 if (ret)
 533                         return ret;
 534         }
 535
 536         tb_switch_for_each_port(sw, port) {
 537                 if (!tb_port_has_remote(port))
 538                         continue;
 539                 ret = tb_create_usb3_tunnels(port->remote->sw);
 540                 if (ret)
 541                         return ret;
 542         }
 543
 544         return 0;
 545 }
 546
 547 static void tb_scan_port(struct tb_port *port);
 548
 549 /*
 550  * tb_scan_switch() - scan for and initialize downstream switches
 551  */
 552 static void tb_scan_switch(struct tb_switch *sw)
 553 {
 554         struct tb_port *port;
 555
 556         pm_runtime_get_sync(&sw->dev);
 557
 558         tb_switch_for_each_port(sw, port)
 559                 tb_scan_port(port);
 560
 561         pm_runtime_mark_last_busy(&sw->dev);
 562         pm_runtime_put_autosuspend(&sw->dev);
 563 }
 564
 565 /*
 566  * tb_scan_port() - check for and initialize switches below port
 567  */
 568 static void tb_scan_port(struct tb_port *port)
 569 {
 570         struct tb_cm *tcm = tb_priv(port->sw->tb);
 571         struct tb_port *upstream_port;
 572         struct tb_switch *sw;
 573
 574         if (tb_is_upstream_port(port))
 575                 return;
 576
 577         if (tb_port_is_dpout(port) && tb_dp_port_hpd_is_active(port) == 1 &&
 578             !tb_dp_port_is_enabled(port)) {
 579                 tb_port_dbg(port, "DP adapter HPD set, queuing hotplug\n");
 580                 tb_queue_hotplug(port->sw->tb, tb_route(port->sw), port->port,
 581                                  false);
 582                 return;
 583         }
 584
 585         if (port->config.type != TB_TYPE_PORT)
 586                 return;
 587         if (port->dual_link_port && port->link_nr)
 588                 return; /*
 589                          * Downstream switch is reachable through two ports.
 590                          * Only scan on the primary port (link_nr == 0).
 591                          */
 592         if (tb_wait_for_port(port, false) <= 0)
 593                 return;
 594         if (port->remote) {
 595                 tb_port_dbg(port, "port already has a remote\n");
 596                 return;
 597         }
 598
 599         tb_retimer_scan(port, true);
 600
 601         sw = tb_switch_alloc(port->sw->tb, &port->sw->dev,
 602                              tb_downstream_route(port));
 603         if (IS_ERR(sw)) {
 604                 /*
 605                  * If there is an error accessing the connected switch
 606                  * it may be connected to another domain. Also we allow
 607                  * the other domain to be connected to a max depth switch.
 608                  */
 609                 if (PTR_ERR(sw) == -EIO || PTR_ERR(sw) == -EADDRNOTAVAIL)
 610                         tb_scan_xdomain(port);
 611                 return;
 612         }
 613
 614         if (tb_switch_configure(sw)) {
 615                 tb_switch_put(sw);
 616                 return;
 617         }
 618
 619         /*
 620          * If there was previously another domain connected remove it
 621          * first.
 622          */
 623         if (port->xdomain) {
 624                 tb_xdomain_remove(port->xdomain);
 625                 tb_port_unconfigure_xdomain(port);
 626                 port->xdomain = NULL;
 627         }
 628
 629         /*
 630          * Do not send uevents until we have discovered all existing
 631          * tunnels and know which switches were authorized already by
 632          * the boot firmware.
 633          */
 634         if (!tcm->hotplug_active)
 635                 dev_set_uevent_suppress(&sw->dev, true);
 636
 637         /*
 638          * At the moment Thunderbolt 2 and beyond (devices with LC) we
 639          * can support runtime PM.
 640          */
 641         sw->rpm = sw->generation > 1;
 642
 643         if (tb_switch_add(sw)) {
 644                 tb_switch_put(sw);
 645                 return;
 646         }
 647
 648         /* Link the switches using both links if available */
 649         upstream_port = tb_upstream_port(sw);
 650         port->remote = upstream_port;
 651         upstream_port->remote = port;
 652         if (port->dual_link_port && upstream_port->dual_link_port) {
 653                 port->dual_link_port->remote = upstream_port->dual_link_port;
 654                 upstream_port->dual_link_port->remote = port->dual_link_port;
 655         }
 656
 657         /* Enable lane bonding if supported */
 658         tb_switch_lane_bonding_enable(sw);
 659         /* Set the link configured */
 660         tb_switch_configure_link(sw);
 661
 662         if (tb_enable_tmu(sw))
 663                 tb_sw_warn(sw, "failed to enable TMU\n");
 664
 665         /* Scan upstream retimers */
 666         tb_retimer_scan(upstream_port, true);
 667
 668         /*
 669          * Create USB 3.x tunnels only when the switch is plugged to the
 670          * domain. This is because we scan the domain also during discovery
 671          * and want to discover existing USB 3.x tunnels before we create
 672          * any new.
 673          */
 674         if (tcm->hotplug_active && tb_tunnel_usb3(sw->tb, sw))
 675                 tb_sw_warn(sw, "USB3 tunnel creation failed\n");
 676
 677         tb_add_dp_resources(sw);
 678         tb_scan_switch(sw);
 679 }
 680
 681 static void tb_deactivate_and_free_tunnel(struct tb_tunnel *tunnel)
 682 {
 683         struct tb_port *src_port, *dst_port;
 684         struct tb *tb;
 685
 686         if (!tunnel)
 687                 return;
 688
 689         tb_tunnel_deactivate(tunnel);
 690         list_del(&tunnel->list);
 691
 692         tb = tunnel->tb;
 693         src_port = tunnel->src_port;
 694         dst_port = tunnel->dst_port;
 695
 696         switch (tunnel->type) {
 697         case TB_TUNNEL_DP:
 698                 /*
 699                  * In case of DP tunnel make sure the DP IN resource is
 700                  * deallocated properly.
 701                  */
 702                 tb_switch_dealloc_dp_resource(src_port->sw, src_port);
 703                 /* Now we can allow the domain to runtime suspend again */
 704                 pm_runtime_mark_last_busy(&dst_port->sw->dev);
 705                 pm_runtime_put_autosuspend(&dst_port->sw->dev);
 706                 pm_runtime_mark_last_busy(&src_port->sw->dev);
 707                 pm_runtime_put_autosuspend(&src_port->sw->dev);
 708                 fallthrough;
 709
 710         case TB_TUNNEL_USB3:
 711                 tb_reclaim_usb3_bandwidth(tb, src_port, dst_port);
 712                 break;
 713
 714         default:
 715                 /*
 716                  * PCIe and DMA tunnels do not consume guaranteed
 717                  * bandwidth.
 718                  */
 719                 break;
 720         }
 721
 722         tb_tunnel_free(tunnel);
 723 }
 724
 725 /*
 726  * tb_free_invalid_tunnels() - destroy tunnels of devices that have gone away
 727  */
 728 static void tb_free_invalid_tunnels(struct tb *tb)
 729 {
 730         struct tb_cm *tcm = tb_priv(tb);
 731         struct tb_tunnel *tunnel;
 732         struct tb_tunnel *n;
 733
 734         list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) {
 735                 if (tb_tunnel_is_invalid(tunnel))
 736                         tb_deactivate_and_free_tunnel(tunnel);
 737         }
 738 }
 739
 740 /*
 741  * tb_free_unplugged_children() - traverse hierarchy and free unplugged switches
 742  */
 743 static void tb_free_unplugged_children(struct tb_switch *sw)
 744 {
 745         struct tb_port *port;
 746
 747         tb_switch_for_each_port(sw, port) {
 748                 if (!tb_port_has_remote(port))
 749                         continue;
 750
 751                 if (port->remote->sw->is_unplugged) {
 752                         tb_retimer_remove_all(port);
 753                         tb_remove_dp_resources(port->remote->sw);
 754                         tb_switch_unconfigure_link(port->remote->sw);
 755                         tb_switch_lane_bonding_disable(port->remote->sw);
 756                         tb_switch_remove(port->remote->sw);
 757                         port->remote = NULL;
 758                         if (port->dual_link_port)
 759                                 port->dual_link_port->remote = NULL;
 760                 } else {
 761                         tb_free_unplugged_children(port->remote->sw);
 762                 }
 763         }
 764 }
 765
 766 static struct tb_port *tb_find_pcie_down(struct tb_switch *sw,
 767                                          const struct tb_port *port)
 768 {
 769         struct tb_port *down = NULL;
 770
 771         /*
 772          * To keep plugging devices consistently in the same PCIe
 773          * hierarchy, do mapping here for switch downstream PCIe ports.
 774          */
 775         if (tb_switch_is_usb4(sw)) {
 776                 down = usb4_switch_map_pcie_down(sw, port);
 777         } else if (!tb_route(sw)) {
 778                 int phy_port = tb_phy_port_from_link(port->port);
 779                 int index;
 780
 781                 /*
 782                  * Hard-coded Thunderbolt port to PCIe down port mapping
 783                  * per controller.
 784                  */
 785                 if (tb_switch_is_cactus_ridge(sw) ||
 786                     tb_switch_is_alpine_ridge(sw))
 787                         index = !phy_port ? 6 : 7;
 788                 else if (tb_switch_is_falcon_ridge(sw))
 789                         index = !phy_port ? 6 : 8;
 790                 else if (tb_switch_is_titan_ridge(sw))
 791                         index = !phy_port ? 8 : 9;
 792                 else
 793                         goto out;
 794
 795                 /* Validate the hard-coding */
 796                 if (WARN_ON(index > sw->config.max_port_number))
 797                         goto out;
 798
 799                 down = &sw->ports[index];
 800         }
 801
 802         if (down) {
 803                 if (WARN_ON(!tb_port_is_pcie_down(down)))
 804                         goto out;
 805                 if (tb_pci_port_is_enabled(down))
 806                         goto out;
 807
 808                 return down;
 809         }
 810
 811 out:
 812         return tb_find_unused_port(sw, TB_TYPE_PCIE_DOWN);
 813 }
 814
 815 static struct tb_port *tb_find_dp_out(struct tb *tb, struct tb_port *in)
 816 {
 817         struct tb_port *host_port, *port;
 818         struct tb_cm *tcm = tb_priv(tb);
 819
 820         host_port = tb_route(in->sw) ?
 821                 tb_port_at(tb_route(in->sw), tb->root_switch) : NULL;
 822
 823         list_for_each_entry(port, &tcm->dp_resources, list) {
 824                 if (!tb_port_is_dpout(port))
 825                         continue;
 826
 827                 if (tb_port_is_enabled(port)) {
 828                         tb_port_dbg(port, "in use\n");
 829                         continue;
 830                 }
 831
 832                 tb_port_dbg(port, "DP OUT available\n");
 833
 834                 /*
 835                  * Keep the DP tunnel under the topology starting from
 836                  * the same host router downstream port.
 837                  */
 838                 if (host_port && tb_route(port->sw)) {
 839                         struct tb_port *p;
 840
 841                         p = tb_port_at(tb_route(port->sw), tb->root_switch);
 842                         if (p != host_port)
 843                                 continue;
 844                 }
 845
 846                 return port;
 847         }
 848
 849         return NULL;
 850 }
 851
 852 static void tb_tunnel_dp(struct tb *tb)
 853 {
 854         int available_up, available_down, ret;
 855         struct tb_cm *tcm = tb_priv(tb);
 856         struct tb_port *port, *in, *out;
 857         struct tb_tunnel *tunnel;
 858
 859         if (!tb_acpi_may_tunnel_dp()) {
 860                 tb_dbg(tb, "DP tunneling disabled, not creating tunnel\n");
 861                 return;
 862         }
 863
 864         /*
 865          * Find pair of inactive DP IN and DP OUT adapters and then
 866          * establish a DP tunnel between them.
 867          */
 868         tb_dbg(tb, "looking for DP IN <-> DP OUT pairs:\n");
 869
 870         in = NULL;
 871         out = NULL;
 872         list_for_each_entry(port, &tcm->dp_resources, list) {
 873                 if (!tb_port_is_dpin(port))
 874                         continue;
 875
 876                 if (tb_port_is_enabled(port)) {
 877                         tb_port_dbg(port, "in use\n");
 878                         continue;
 879                 }
 880
 881                 tb_port_dbg(port, "DP IN available\n");
 882
 883                 out = tb_find_dp_out(tb, port);
 884                 if (out) {
 885                         in = port;
 886                         break;
 887                 }
 888         }
 889
 890         if (!in) {
 891                 tb_dbg(tb, "no suitable DP IN adapter available, not tunneling\n");
 892                 return;
 893         }
 894         if (!out) {
 895                 tb_dbg(tb, "no suitable DP OUT adapter available, not tunneling\n");
 896                 return;
 897         }
 898
 899         /*
 900          * DP stream needs the domain to be active so runtime resume
 901          * both ends of the tunnel.
 902          *
 903          * This should bring the routers in the middle active as well
 904          * and keeps the domain from runtime suspending while the DP
 905          * tunnel is active.
 906          */
 907         pm_runtime_get_sync(&in->sw->dev);
 908         pm_runtime_get_sync(&out->sw->dev);
 909
 910         if (tb_switch_alloc_dp_resource(in->sw, in)) {
 911                 tb_port_dbg(in, "no resource available for DP IN, not tunneling\n");
 912                 goto err_rpm_put;
 913         }
 914
 915         /* Make all unused USB3 bandwidth available for the new DP tunnel */
 916         ret = tb_release_unused_usb3_bandwidth(tb, in, out);
 917         if (ret) {
 918                 tb_warn(tb, "failed to release unused bandwidth\n");
 919                 goto err_dealloc_dp;
 920         }
 921
 922         ret = tb_available_bandwidth(tb, in, out, &available_up,
 923                                      &available_down);
 924         if (ret)
 925                 goto err_reclaim;
 926
 927         tb_dbg(tb, "available bandwidth for new DP tunnel %u/%u Mb/s\n",
 928                available_up, available_down);
 929
 930         tunnel = tb_tunnel_alloc_dp(tb, in, out, available_up, available_down);
 931         if (!tunnel) {
 932                 tb_port_dbg(out, "could not allocate DP tunnel\n");
 933                 goto err_reclaim;
 934         }
 935
 936         if (tb_tunnel_activate(tunnel)) {
 937                 tb_port_info(out, "DP tunnel activation failed, aborting\n");
 938                 goto err_free;
 939         }
 940
 941         list_add_tail(&tunnel->list, &tcm->tunnel_list);
 942         tb_reclaim_usb3_bandwidth(tb, in, out);
 943         return;
 944
 945 err_free:
 946         tb_tunnel_free(tunnel);
 947 err_reclaim:
 948         tb_reclaim_usb3_bandwidth(tb, in, out);
 949 err_dealloc_dp:
 950         tb_switch_dealloc_dp_resource(in->sw, in);
 951 err_rpm_put:
 952         pm_runtime_mark_last_busy(&out->sw->dev);
 953         pm_runtime_put_autosuspend(&out->sw->dev);
 954         pm_runtime_mark_last_busy(&in->sw->dev);
 955         pm_runtime_put_autosuspend(&in->sw->dev);
 956 }
 957
 958 static void tb_dp_resource_unavailable(struct tb *tb, struct tb_port *port)
 959 {
 960         struct tb_port *in, *out;
 961         struct tb_tunnel *tunnel;
 962
 963         if (tb_port_is_dpin(port)) {
 964                 tb_port_dbg(port, "DP IN resource unavailable\n");
 965                 in = port;
 966                 out = NULL;
 967         } else {
 968                 tb_port_dbg(port, "DP OUT resource unavailable\n");
 969                 in = NULL;
 970                 out = port;
 971         }
 972
 973         tunnel = tb_find_tunnel(tb, TB_TUNNEL_DP, in, out);
 974         tb_deactivate_and_free_tunnel(tunnel);
 975         list_del_init(&port->list);
 976
 977         /*
 978          * See if there is another DP OUT port that can be used for
 979          * to create another tunnel.
 980          */
 981         tb_tunnel_dp(tb);
 982 }
 983
 984 static void tb_dp_resource_available(struct tb *tb, struct tb_port *port)
 985 {
 986         struct tb_cm *tcm = tb_priv(tb);
 987         struct tb_port *p;
 988
 989         if (tb_port_is_enabled(port))
 990                 return;
 991
 992         list_for_each_entry(p, &tcm->dp_resources, list) {
 993                 if (p == port)
 994                         return;
 995         }
 996
 997         tb_port_dbg(port, "DP %s resource available\n",
 998                     tb_port_is_dpin(port) ? "IN" : "OUT");
 999         list_add_tail(&port->list, &tcm->dp_resources);
1000
1001         /* Look for suitable DP IN <-> DP OUT pairs now */
1002         tb_tunnel_dp(tb);
1003 }
1004
1005 static void tb_disconnect_and_release_dp(struct tb *tb)
1006 {
1007         struct tb_cm *tcm = tb_priv(tb);
1008         struct tb_tunnel *tunnel, *n;
1009
1010         /*
1011          * Tear down all DP tunnels and release their resources. They
1012          * will be re-established after resume based on plug events.
1013          */
1014         list_for_each_entry_safe_reverse(tunnel, n, &tcm->tunnel_list, list) {
1015                 if (tb_tunnel_is_dp(tunnel))
1016                         tb_deactivate_and_free_tunnel(tunnel);
1017         }
1018
1019         while (!list_empty(&tcm->dp_resources)) {
1020                 struct tb_port *port;
1021
1022                 port = list_first_entry(&tcm->dp_resources,
1023                                         struct tb_port, list);
1024                 list_del_init(&port->list);
1025         }
1026 }
1027
1028 static int tb_disconnect_pci(struct tb *tb, struct tb_switch *sw)
1029 {
1030         struct tb_tunnel *tunnel;
1031         struct tb_port *up;
1032
1033         up = tb_switch_find_port(sw, TB_TYPE_PCIE_UP);
1034         if (WARN_ON(!up))
1035                 return -ENODEV;
1036
1037         tunnel = tb_find_tunnel(tb, TB_TUNNEL_PCI, NULL, up);
1038         if (WARN_ON(!tunnel))
1039                 return -ENODEV;
1040
1041         tb_tunnel_deactivate(tunnel);
1042         list_del(&tunnel->list);
1043         tb_tunnel_free(tunnel);
1044         return 0;
1045 }
1046
1047 static int tb_tunnel_pci(struct tb *tb, struct tb_switch *sw)
1048 {
1049         struct tb_port *up, *down, *port;
1050         struct tb_cm *tcm = tb_priv(tb);
1051         struct tb_switch *parent_sw;
1052         struct tb_tunnel *tunnel;
1053
1054         up = tb_switch_find_port(sw, TB_TYPE_PCIE_UP);
1055         if (!up)
1056                 return 0;
1057
1058         /*
1059          * Look up available down port. Since we are chaining it should
1060          * be found right above this switch.
1061          */
1062         parent_sw = tb_to_switch(sw->dev.parent);
1063         port = tb_port_at(tb_route(sw), parent_sw);
1064         down = tb_find_pcie_down(parent_sw, port);
1065         if (!down)
1066                 return 0;
1067
1068         tunnel = tb_tunnel_alloc_pci(tb, up, down);
1069         if (!tunnel)
1070                 return -ENOMEM;
1071
1072         if (tb_tunnel_activate(tunnel)) {
1073                 tb_port_info(up,
1074                              "PCIe tunnel activation failed, aborting\n");
1075                 tb_tunnel_free(tunnel);
1076                 return -EIO;
1077         }
1078
1079         list_add_tail(&tunnel->list, &tcm->tunnel_list);
1080         return 0;
1081 }
1082
1083 static int tb_approve_xdomain_paths(struct tb *tb, struct tb_xdomain *xd,
1084                                     int transmit_path, int transmit_ring,
1085                                     int receive_path, int receive_ring)
1086 {
1087         struct tb_cm *tcm = tb_priv(tb);
1088         struct tb_port *nhi_port, *dst_port;
1089         struct tb_tunnel *tunnel;
1090         struct tb_switch *sw;
1091
1092         sw = tb_to_switch(xd->dev.parent);
1093         dst_port = tb_port_at(xd->route, sw);
1094         nhi_port = tb_switch_find_port(tb->root_switch, TB_TYPE_NHI);
1095
1096         mutex_lock(&tb->lock);
1097         tunnel = tb_tunnel_alloc_dma(tb, nhi_port, dst_port, transmit_path,
1098                                      transmit_ring, receive_path, receive_ring);
1099         if (!tunnel) {
1100                 mutex_unlock(&tb->lock);
1101                 return -ENOMEM;
1102         }
1103
1104         if (tb_tunnel_activate(tunnel)) {
1105                 tb_port_info(nhi_port,
1106                              "DMA tunnel activation failed, aborting\n");
1107                 tb_tunnel_free(tunnel);
1108                 mutex_unlock(&tb->lock);
1109                 return -EIO;
1110         }
1111
1112         list_add_tail(&tunnel->list, &tcm->tunnel_list);
1113         mutex_unlock(&tb->lock);
1114         return 0;
1115 }
1116
1117 static void __tb_disconnect_xdomain_paths(struct tb *tb, struct tb_xdomain *xd,
1118                                           int transmit_path, int transmit_ring,
1119                                           int receive_path, int receive_ring)
1120 {
1121         struct tb_cm *tcm = tb_priv(tb);
1122         struct tb_port *nhi_port, *dst_port;
1123         struct tb_tunnel *tunnel, *n;
1124         struct tb_switch *sw;
1125
1126         sw = tb_to_switch(xd->dev.parent);
1127         dst_port = tb_port_at(xd->route, sw);
1128         nhi_port = tb_switch_find_port(tb->root_switch, TB_TYPE_NHI);
1129
1130         list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) {
1131                 if (!tb_tunnel_is_dma(tunnel))
1132                         continue;
1133                 if (tunnel->src_port != nhi_port || tunnel->dst_port != dst_port)
1134                         continue;
1135
1136                 if (tb_tunnel_match_dma(tunnel, transmit_path, transmit_ring,
1137                                         receive_path, receive_ring))
1138                         tb_deactivate_and_free_tunnel(tunnel);
1139         }
1140 }
1141
1142 static int tb_disconnect_xdomain_paths(struct tb *tb, struct tb_xdomain *xd,
1143                                        int transmit_path, int transmit_ring,
1144                                        int receive_path, int receive_ring)
1145 {
1146         if (!xd->is_unplugged) {
1147                 mutex_lock(&tb->lock);
1148                 __tb_disconnect_xdomain_paths(tb, xd, transmit_path,
1149                                               transmit_ring, receive_path,
1150                                               receive_ring);
1151                 mutex_unlock(&tb->lock);
1152         }
1153         return 0;
1154 }
1155
1156 /* hotplug handling */
1157
1158 /*
1159  * tb_handle_hotplug() - handle hotplug event
1160  *
1161  * Executes on tb->wq.
1162  */
1163 static void tb_handle_hotplug(struct work_struct *work)
1164 {
1165         struct tb_hotplug_event *ev = container_of(work, typeof(*ev), work);
1166         struct tb *tb = ev->tb;
1167         struct tb_cm *tcm = tb_priv(tb);
1168         struct tb_switch *sw;
1169         struct tb_port *port;
1170
1171         /* Bring the domain back from sleep if it was suspended */
1172         pm_runtime_get_sync(&tb->dev);
1173
1174         mutex_lock(&tb->lock);
1175         if (!tcm->hotplug_active)
1176                 goto out; /* during init, suspend or shutdown */
1177
1178         sw = tb_switch_find_by_route(tb, ev->route);
1179         if (!sw) {
1180                 tb_warn(tb,
1181                         "hotplug event from non existent switch %llx:%x (unplug: %d)\n",
1182                         ev->route, ev->port, ev->unplug);
1183                 goto out;
1184         }
1185         if (ev->port > sw->config.max_port_number) {
1186                 tb_warn(tb,
1187                         "hotplug event from non existent port %llx:%x (unplug: %d)\n",
1188                         ev->route, ev->port, ev->unplug);
1189                 goto put_sw;
1190         }
1191         port = &sw->ports[ev->port];
1192         if (tb_is_upstream_port(port)) {
1193                 tb_dbg(tb, "hotplug event for upstream port %llx:%x (unplug: %d)\n",
1194                        ev->route, ev->port, ev->unplug);
1195                 goto put_sw;
1196         }
1197
1198         pm_runtime_get_sync(&sw->dev);
1199
1200         if (ev->unplug) {
1201                 tb_retimer_remove_all(port);
1202
1203                 if (tb_port_has_remote(port)) {
1204                         tb_port_dbg(port, "switch unplugged\n");
1205                         tb_sw_set_unplugged(port->remote->sw);
1206                         tb_free_invalid_tunnels(tb);
1207                         tb_remove_dp_resources(port->remote->sw);
1208                         tb_switch_tmu_disable(port->remote->sw);
1209                         tb_switch_unconfigure_link(port->remote->sw);
1210                         tb_switch_lane_bonding_disable(port->remote->sw);
1211                         tb_switch_remove(port->remote->sw);
1212                         port->remote = NULL;
1213                         if (port->dual_link_port)
1214                                 port->dual_link_port->remote = NULL;
1215                         /* Maybe we can create another DP tunnel */
1216                         tb_tunnel_dp(tb);
1217                 } else if (port->xdomain) {
1218                         struct tb_xdomain *xd = tb_xdomain_get(port->xdomain);
1219
1220                         tb_port_dbg(port, "xdomain unplugged\n");
1221                         /*
1222                          * Service drivers are unbound during
1223                          * tb_xdomain_remove() so setting XDomain as
1224                          * unplugged here prevents deadlock if they call
1225                          * tb_xdomain_disable_paths(). We will tear down
1226                          * all the tunnels below.
1227                          */
1228                         xd->is_unplugged = true;
1229                         tb_xdomain_remove(xd);
1230                         port->xdomain = NULL;
1231                         __tb_disconnect_xdomain_paths(tb, xd, -1, -1, -1, -1);
1232                         tb_xdomain_put(xd);
1233                         tb_port_unconfigure_xdomain(port);
1234                 } else if (tb_port_is_dpout(port) || tb_port_is_dpin(port)) {
1235                         tb_dp_resource_unavailable(tb, port);
1236                 } else {
1237                         tb_port_dbg(port,
1238                                    "got unplug event for disconnected port, ignoring\n");
1239                 }
1240         } else if (port->remote) {
1241                 tb_port_dbg(port, "got plug event for connected port, ignoring\n");
1242         } else {
1243                 if (tb_port_is_null(port)) {
1244                         tb_port_dbg(port, "hotplug: scanning\n");
1245                         tb_scan_port(port);
1246                         if (!port->remote)
1247                                 tb_port_dbg(port, "hotplug: no switch found\n");
1248                 } else if (tb_port_is_dpout(port) || tb_port_is_dpin(port)) {
1249                         tb_dp_resource_available(tb, port);
1250                 }
1251         }
1252
1253         pm_runtime_mark_last_busy(&sw->dev);
1254         pm_runtime_put_autosuspend(&sw->dev);
1255
1256 put_sw:
1257         tb_switch_put(sw);
1258 out:
1259         mutex_unlock(&tb->lock);
1260
1261         pm_runtime_mark_last_busy(&tb->dev);
1262         pm_runtime_put_autosuspend(&tb->dev);
1263
1264         kfree(ev);
1265 }
1266
1267 /*
1268  * tb_schedule_hotplug_handler() - callback function for the control channel
1269  *
1270  * Delegates to tb_handle_hotplug.
1271  */
1272 static void tb_handle_event(struct tb *tb, enum tb_cfg_pkg_type type,
1273                             const void *buf, size_t size)
1274 {
1275         const struct cfg_event_pkg *pkg = buf;
1276         u64 route;
1277
1278         if (type != TB_CFG_PKG_EVENT) {
1279                 tb_warn(tb, "unexpected event %#x, ignoring\n", type);
1280                 return;
1281         }
1282
1283         route = tb_cfg_get_route(&pkg->header);
1284
1285         if (tb_cfg_ack_plug(tb->ctl, route, pkg->port, pkg->unplug)) {
1286                 tb_warn(tb, "could not ack plug event on %llx:%x\n", route,
1287                         pkg->port);
1288         }
1289
1290         tb_queue_hotplug(tb, route, pkg->port, pkg->unplug);
1291 }
1292
1293 static void tb_stop(struct tb *tb)
1294 {
1295         struct tb_cm *tcm = tb_priv(tb);
1296         struct tb_tunnel *tunnel;
1297         struct tb_tunnel *n;
1298
1299         cancel_delayed_work(&tcm->remove_work);
1300         /* tunnels are only present after everything has been initialized */
1301         list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) {
1302                 /*
1303                  * DMA tunnels require the driver to be functional so we
1304                  * tear them down. Other protocol tunnels can be left
1305                  * intact.
1306                  */
1307                 if (tb_tunnel_is_dma(tunnel))
1308                         tb_tunnel_deactivate(tunnel);
1309                 tb_tunnel_free(tunnel);
1310         }
1311         tb_switch_remove(tb->root_switch);
1312         tcm->hotplug_active = false; /* signal tb_handle_hotplug to quit */
1313 }
1314
1315 static int tb_scan_finalize_switch(struct device *dev, void *data)
1316 {
1317         if (tb_is_switch(dev)) {
1318                 struct tb_switch *sw = tb_to_switch(dev);
1319
1320                 /*
1321                  * If we found that the switch was already setup by the
1322                  * boot firmware, mark it as authorized now before we
1323                  * send uevent to userspace.
1324                  */
1325                 if (sw->boot)
1326                         sw->authorized = 1;
1327
1328                 dev_set_uevent_suppress(dev, false);
1329                 kobject_uevent(&dev->kobj, KOBJ_ADD);
1330                 device_for_each_child(dev, NULL, tb_scan_finalize_switch);
1331         }
1332
1333         return 0;
1334 }
1335
1336 static int tb_start(struct tb *tb)
1337 {
1338         struct tb_cm *tcm = tb_priv(tb);
1339         int ret;
1340
1341         tb->root_switch = tb_switch_alloc(tb, &tb->dev, 0);
1342         if (IS_ERR(tb->root_switch))
1343                 return PTR_ERR(tb->root_switch);
1344
1345         /*
1346          * ICM firmware upgrade needs running firmware and in native
1347          * mode that is not available so disable firmware upgrade of the
1348          * root switch.
1349          */
1350         tb->root_switch->no_nvm_upgrade = true;
1351         /* All USB4 routers support runtime PM */
1352         tb->root_switch->rpm = tb_switch_is_usb4(tb->root_switch);
1353
1354         ret = tb_switch_configure(tb->root_switch);
1355         if (ret) {
1356                 tb_switch_put(tb->root_switch);
1357                 return ret;
1358         }
1359
1360         /* Announce the switch to the world */
1361         ret = tb_switch_add(tb->root_switch);
1362         if (ret) {
1363                 tb_switch_put(tb->root_switch);
1364                 return ret;
1365         }
1366
1367         /* Enable TMU if it is off */
1368         tb_switch_tmu_enable(tb->root_switch);
1369         /* Full scan to discover devices added before the driver was loaded. */
1370         tb_scan_switch(tb->root_switch);
1371         /* Find out tunnels created by the boot firmware */
1372         tb_discover_tunnels(tb->root_switch);
1373         /*
1374          * If the boot firmware did not create USB 3.x tunnels create them
1375          * now for the whole topology.
1376          */
1377         tb_create_usb3_tunnels(tb->root_switch);
1378         /* Add DP IN resources for the root switch */
1379         tb_add_dp_resources(tb->root_switch);
1380         /* Make the discovered switches available to the userspace */
1381         device_for_each_child(&tb->root_switch->dev, NULL,
1382                               tb_scan_finalize_switch);
1383
1384         /* Allow tb_handle_hotplug to progress events */
1385         tcm->hotplug_active = true;
1386         return 0;
1387 }
1388
1389 static int tb_suspend_noirq(struct tb *tb)
1390 {
1391         struct tb_cm *tcm = tb_priv(tb);
1392
1393         tb_dbg(tb, "suspending...\n");
1394         tb_disconnect_and_release_dp(tb);
1395         tb_switch_suspend(tb->root_switch, false);
1396         tcm->hotplug_active = false; /* signal tb_handle_hotplug to quit */
1397         tb_dbg(tb, "suspend finished\n");
1398
1399         return 0;
1400 }
1401
1402 static void tb_restore_children(struct tb_switch *sw)
1403 {
1404         struct tb_port *port;
1405
1406         /* No need to restore if the router is already unplugged */
1407         if (sw->is_unplugged)
1408                 return;
1409
1410         if (tb_enable_tmu(sw))
1411                 tb_sw_warn(sw, "failed to restore TMU configuration\n");
1412
1413         tb_switch_for_each_port(sw, port) {
1414                 if (!tb_port_has_remote(port) && !port->xdomain)
1415                         continue;
1416
1417                 if (port->remote) {
1418                         tb_switch_lane_bonding_enable(port->remote->sw);
1419                         tb_switch_configure_link(port->remote->sw);
1420
1421                         tb_restore_children(port->remote->sw);
1422                 } else if (port->xdomain) {
1423                         tb_port_configure_xdomain(port);
1424                 }
1425         }
1426 }
1427
1428 static int tb_resume_noirq(struct tb *tb)
1429 {
1430         struct tb_cm *tcm = tb_priv(tb);
1431         struct tb_tunnel *tunnel, *n;
1432
1433         tb_dbg(tb, "resuming...\n");
1434
1435         /* remove any pci devices the firmware might have setup */
1436         tb_switch_reset(tb->root_switch);
1437
1438         tb_switch_resume(tb->root_switch);
1439         tb_free_invalid_tunnels(tb);
1440         tb_free_unplugged_children(tb->root_switch);
1441         tb_restore_children(tb->root_switch);
1442         list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list)
1443                 tb_tunnel_restart(tunnel);
1444         if (!list_empty(&tcm->tunnel_list)) {
1445                 /*
1446                  * the pcie links need some time to get going.
1447                  * 100ms works for me...
1448                  */
1449                 tb_dbg(tb, "tunnels restarted, sleeping for 100ms\n");
1450                 msleep(100);
1451         }
1452          /* Allow tb_handle_hotplug to progress events */
1453         tcm->hotplug_active = true;
1454         tb_dbg(tb, "resume finished\n");
1455
1456         return 0;
1457 }
1458
1459 static int tb_free_unplugged_xdomains(struct tb_switch *sw)
1460 {
1461         struct tb_port *port;
1462         int ret = 0;
1463
1464         tb_switch_for_each_port(sw, port) {
1465                 if (tb_is_upstream_port(port))
1466                         continue;
1467                 if (port->xdomain && port->xdomain->is_unplugged) {
1468                         tb_retimer_remove_all(port);
1469                         tb_xdomain_remove(port->xdomain);
1470                         tb_port_unconfigure_xdomain(port);
1471                         port->xdomain = NULL;
1472                         ret++;
1473                 } else if (port->remote) {
1474                         ret += tb_free_unplugged_xdomains(port->remote->sw);
1475                 }
1476         }
1477
1478         return ret;
1479 }
1480
1481 static int tb_freeze_noirq(struct tb *tb)
1482 {
1483         struct tb_cm *tcm = tb_priv(tb);
1484
1485         tcm->hotplug_active = false;
1486         return 0;
1487 }
1488
1489 static int tb_thaw_noirq(struct tb *tb)
1490 {
1491         struct tb_cm *tcm = tb_priv(tb);
1492
1493         tcm->hotplug_active = true;
1494         return 0;
1495 }
1496
1497 static void tb_complete(struct tb *tb)
1498 {
1499         /*
1500          * Release any unplugged XDomains and if there is a case where
1501          * another domain is swapped in place of unplugged XDomain we
1502          * need to run another rescan.
1503          */
1504         mutex_lock(&tb->lock);
1505         if (tb_free_unplugged_xdomains(tb->root_switch))
1506                 tb_scan_switch(tb->root_switch);
1507         mutex_unlock(&tb->lock);
1508 }
1509
1510 static int tb_runtime_suspend(struct tb *tb)
1511 {
1512         struct tb_cm *tcm = tb_priv(tb);
1513
1514         mutex_lock(&tb->lock);
1515         tb_switch_suspend(tb->root_switch, true);
1516         tcm->hotplug_active = false;
1517         mutex_unlock(&tb->lock);
1518
1519         return 0;
1520 }
1521
1522 static void tb_remove_work(struct work_struct *work)
1523 {
1524         struct tb_cm *tcm = container_of(work, struct tb_cm, remove_work.work);
1525         struct tb *tb = tcm_to_tb(tcm);
1526
1527         mutex_lock(&tb->lock);
1528         if (tb->root_switch) {
1529                 tb_free_unplugged_children(tb->root_switch);
1530                 tb_free_unplugged_xdomains(tb->root_switch);
1531         }
1532         mutex_unlock(&tb->lock);
1533 }
1534
1535 static int tb_runtime_resume(struct tb *tb)
1536 {
1537         struct tb_cm *tcm = tb_priv(tb);
1538         struct tb_tunnel *tunnel, *n;
1539
1540         mutex_lock(&tb->lock);
1541         tb_switch_resume(tb->root_switch);
1542         tb_free_invalid_tunnels(tb);
1543         tb_restore_children(tb->root_switch);
1544         list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list)
1545                 tb_tunnel_restart(tunnel);
1546         tcm->hotplug_active = true;
1547         mutex_unlock(&tb->lock);
1548
1549         /*
1550          * Schedule cleanup of any unplugged devices. Run this in a
1551          * separate thread to avoid possible deadlock if the device
1552          * removal runtime resumes the unplugged device.
1553          */
1554         queue_delayed_work(tb->wq, &tcm->remove_work, msecs_to_jiffies(50));
1555         return 0;
1556 }
1557
1558 static const struct tb_cm_ops tb_cm_ops = {
1559         .start = tb_start,
1560         .stop = tb_stop,
1561         .suspend_noirq = tb_suspend_noirq,
1562         .resume_noirq = tb_resume_noirq,
1563         .freeze_noirq = tb_freeze_noirq,
1564         .thaw_noirq = tb_thaw_noirq,
1565         .complete = tb_complete,
1566         .runtime_suspend = tb_runtime_suspend,
1567         .runtime_resume = tb_runtime_resume,
1568         .handle_event = tb_handle_event,
1569         .disapprove_switch = tb_disconnect_pci,
1570         .approve_switch = tb_tunnel_pci,
1571         .approve_xdomain_paths = tb_approve_xdomain_paths,
1572         .disconnect_xdomain_paths = tb_disconnect_xdomain_paths,
1573 };
1574
1575 /*
1576  * During suspend the Thunderbolt controller is reset and all PCIe
1577  * tunnels are lost. The NHI driver will try to reestablish all tunnels
1578  * during resume. This adds device links between the tunneled PCIe
1579  * downstream ports and the NHI so that the device core will make sure
1580  * NHI is resumed first before the rest.
1581  */
1582 static void tb_apple_add_links(struct tb_nhi *nhi)
1583 {
1584         struct pci_dev *upstream, *pdev;
1585
1586         if (!x86_apple_machine)
1587                 return;
1588
1589         switch (nhi->pdev->device) {
1590         case PCI_DEVICE_ID_INTEL_LIGHT_RIDGE:
1591         case PCI_DEVICE_ID_INTEL_CACTUS_RIDGE_4C:
1592         case PCI_DEVICE_ID_INTEL_FALCON_RIDGE_2C_NHI:
1593         case PCI_DEVICE_ID_INTEL_FALCON_RIDGE_4C_NHI:
1594                 break;
1595         default:
1596                 return;
1597         }
1598
1599         upstream = pci_upstream_bridge(nhi->pdev);
1600         while (upstream) {
1601                 if (!pci_is_pcie(upstream))
1602                         return;
1603                 if (pci_pcie_type(upstream) == PCI_EXP_TYPE_UPSTREAM)
1604                         break;
1605                 upstream = pci_upstream_bridge(upstream);
1606         }
1607
1608         if (!upstream)
1609                 return;
1610
1611         /*
1612          * For each hotplug downstream port, create add device link
1613          * back to NHI so that PCIe tunnels can be re-established after
1614          * sleep.
1615          */
1616         for_each_pci_bridge(pdev, upstream->subordinate) {
1617                 const struct device_link *link;
1618
1619                 if (!pci_is_pcie(pdev))
1620                         continue;
1621                 if (pci_pcie_type(pdev) != PCI_EXP_TYPE_DOWNSTREAM ||
1622                     !pdev->is_hotplug_bridge)
1623                         continue;
1624
1625                 link = device_link_add(&pdev->dev, &nhi->pdev->dev,
1626                                        DL_FLAG_AUTOREMOVE_SUPPLIER |
1627                                        DL_FLAG_PM_RUNTIME);
1628                 if (link) {
1629                         dev_dbg(&nhi->pdev->dev, "created link from %s\n",
1630                                 dev_name(&pdev->dev));
1631                 } else {
1632                         dev_warn(&nhi->pdev->dev, "device link creation from %s failed\n",
1633                                  dev_name(&pdev->dev));
1634                 }
1635         }
1636 }
1637
1638 struct tb *tb_probe(struct tb_nhi *nhi)
1639 {
1640         struct tb_cm *tcm;
1641         struct tb *tb;
1642
1643         tb = tb_domain_alloc(nhi, TB_TIMEOUT, sizeof(*tcm));
1644         if (!tb)
1645                 return NULL;
1646
1647         if (tb_acpi_may_tunnel_pcie())
1648                 tb->security_level = TB_SECURITY_USER;
1649         else
1650                 tb->security_level = TB_SECURITY_NOPCIE;
1651
1652         tb->cm_ops = &tb_cm_ops;
1653
1654         tcm = tb_priv(tb);
1655         INIT_LIST_HEAD(&tcm->tunnel_list);
1656         INIT_LIST_HEAD(&tcm->dp_resources);
1657         INIT_DELAYED_WORK(&tcm->remove_work, tb_remove_work);
1658
1659         tb_dbg(tb, "using software connection manager\n");
1660
1661         tb_apple_add_links(nhi);
1662         tb_acpi_add_links(nhi);
1663
1664         return tb;
1665 }