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
  14 #include "tb.h"
  15 #include "tb_regs.h"
  16 #include "tunnel.h"
  17
  18 /**
  19  * struct tb_cm - Simple Thunderbolt connection manager
  20  * @tunnel_list: List of active tunnels
  21  * @dp_resources: List of available DP resources for DP tunneling
  22  * @hotplug_active: tb_handle_hotplug will stop progressing plug
  23  *                  events and exit if this is not set (it needs to
  24  *                  acquire the lock one more time). Used to drain wq
  25  *                  after cfg has been paused.
  26  * @remove_work: Work used to remove any unplugged routers after
  27  *               runtime resume
  28  */
  29 struct tb_cm {
  30         struct list_head tunnel_list;
  31         struct list_head dp_resources;
  32         bool hotplug_active;
  33         struct delayed_work remove_work;
  34 };
  35
  36 static inline struct tb *tcm_to_tb(struct tb_cm *tcm)
  37 {
  38         return ((void *)tcm - sizeof(struct tb));
  39 }
  40
  41 struct tb_hotplug_event {
  42         struct work_struct work;
  43         struct tb *tb;
  44         u64 route;
  45         u8 port;
  46         bool unplug;
  47 };
  48
  49 static void tb_handle_hotplug(struct work_struct *work);
  50
  51 static void tb_queue_hotplug(struct tb *tb, u64 route, u8 port, bool unplug)
  52 {
  53         struct tb_hotplug_event *ev;
  54
  55         ev = kmalloc(sizeof(*ev), GFP_KERNEL);
  56         if (!ev)
  57                 return;
  58
  59         ev->tb = tb;
  60         ev->route = route;
  61         ev->port = port;
  62         ev->unplug = unplug;
  63         INIT_WORK(&ev->work, tb_handle_hotplug);
  64         queue_work(tb->wq, &ev->work);
  65 }
  66
  67 /* enumeration & hot plug handling */
  68
  69 static void tb_add_dp_resources(struct tb_switch *sw)
  70 {
  71         struct tb_cm *tcm = tb_priv(sw->tb);
  72         struct tb_port *port;
  73
  74         tb_switch_for_each_port(sw, port) {
  75                 if (!tb_port_is_dpin(port))
  76                         continue;
  77
  78                 if (!tb_switch_query_dp_resource(sw, port))
  79                         continue;
  80
  81                 list_add_tail(&port->list, &tcm->dp_resources);
  82                 tb_port_dbg(port, "DP IN resource available\n");
  83         }
  84 }
  85
  86 static void tb_remove_dp_resources(struct tb_switch *sw)
  87 {
  88         struct tb_cm *tcm = tb_priv(sw->tb);
  89         struct tb_port *port, *tmp;
  90
  91         /* Clear children resources first */
  92         tb_switch_for_each_port(sw, port) {
  93                 if (tb_port_has_remote(port))
  94                         tb_remove_dp_resources(port->remote->sw);
  95         }
  96
  97         list_for_each_entry_safe(port, tmp, &tcm->dp_resources, list) {
  98                 if (port->sw == sw) {
  99                         tb_port_dbg(port, "DP OUT resource unavailable\n");
 100                         list_del_init(&port->list);
 101                 }
 102         }
 103 }
 104
 105 static void tb_discover_tunnels(struct tb_switch *sw)
 106 {
 107         struct tb *tb = sw->tb;
 108         struct tb_cm *tcm = tb_priv(tb);
 109         struct tb_port *port;
 110
 111         tb_switch_for_each_port(sw, port) {
 112                 struct tb_tunnel *tunnel = NULL;
 113
 114                 switch (port->config.type) {
 115                 case TB_TYPE_DP_HDMI_IN:
 116                         tunnel = tb_tunnel_discover_dp(tb, port);
 117                         break;
 118
 119                 case TB_TYPE_PCIE_DOWN:
 120                         tunnel = tb_tunnel_discover_pci(tb, port);
 121                         break;
 122
 123                 case TB_TYPE_USB3_DOWN:
 124                         tunnel = tb_tunnel_discover_usb3(tb, port);
 125                         break;
 126
 127                 default:
 128                         break;
 129                 }
 130
 131                 if (!tunnel)
 132                         continue;
 133
 134                 if (tb_tunnel_is_pci(tunnel)) {
 135                         struct tb_switch *parent = tunnel->dst_port->sw;
 136
 137                         while (parent != tunnel->src_port->sw) {
 138                                 parent->boot = true;
 139                                 parent = tb_switch_parent(parent);
 140                         }
 141                 }
 142
 143                 list_add_tail(&tunnel->list, &tcm->tunnel_list);
 144         }
 145
 146         tb_switch_for_each_port(sw, port) {
 147                 if (tb_port_has_remote(port))
 148                         tb_discover_tunnels(port->remote->sw);
 149         }
 150 }
 151
 152 static int tb_port_configure_xdomain(struct tb_port *port)
 153 {
 154         /*
 155          * XDomain paths currently only support single lane so we must
 156          * disable the other lane according to USB4 spec.
 157          */
 158         tb_port_disable(port->dual_link_port);
 159
 160         if (tb_switch_is_usb4(port->sw))
 161                 return usb4_port_configure_xdomain(port);
 162         return tb_lc_configure_xdomain(port);
 163 }
 164
 165 static void tb_port_unconfigure_xdomain(struct tb_port *port)
 166 {
 167         if (tb_switch_is_usb4(port->sw))
 168                 usb4_port_unconfigure_xdomain(port);
 169         else
 170                 tb_lc_unconfigure_xdomain(port);
 171
 172         tb_port_enable(port->dual_link_port);
 173 }
 174
 175 static void tb_scan_xdomain(struct tb_port *port)
 176 {
 177         struct tb_switch *sw = port->sw;
 178         struct tb *tb = sw->tb;
 179         struct tb_xdomain *xd;
 180         u64 route;
 181
 182         if (!tb_is_xdomain_enabled())
 183                 return;
 184
 185         route = tb_downstream_route(port);
 186         xd = tb_xdomain_find_by_route(tb, route);
 187         if (xd) {
 188                 tb_xdomain_put(xd);
 189                 return;
 190         }
 191
 192         xd = tb_xdomain_alloc(tb, &sw->dev, route, tb->root_switch->uuid,
 193                               NULL);
 194         if (xd) {
 195                 tb_port_at(route, sw)->xdomain = xd;
 196                 tb_port_configure_xdomain(port);
 197                 tb_xdomain_add(xd);
 198         }
 199 }
 200
 201 static int tb_enable_tmu(struct tb_switch *sw)
 202 {
 203         int ret;
 204
 205         /* If it is already enabled in correct mode, don't touch it */
 206         if (tb_switch_tmu_is_enabled(sw))
 207                 return 0;
 208
 209         ret = tb_switch_tmu_disable(sw);
 210         if (ret)
 211                 return ret;
 212
 213         ret = tb_switch_tmu_post_time(sw);
 214         if (ret)
 215                 return ret;
 216
 217         return tb_switch_tmu_enable(sw);
 218 }
 219
 220 /**
 221  * tb_find_unused_port() - return the first inactive port on @sw
 222  * @sw: Switch to find the port on
 223  * @type: Port type to look for
 224  */
 225 static struct tb_port *tb_find_unused_port(struct tb_switch *sw,
 226                                            enum tb_port_type type)
 227 {
 228         struct tb_port *port;
 229
 230         tb_switch_for_each_port(sw, port) {
 231                 if (tb_is_upstream_port(port))
 232                         continue;
 233                 if (port->config.type != type)
 234                         continue;
 235                 if (!port->cap_adap)
 236                         continue;
 237                 if (tb_port_is_enabled(port))
 238                         continue;
 239                 return port;
 240         }
 241         return NULL;
 242 }
 243
 244 static struct tb_port *tb_find_usb3_down(struct tb_switch *sw,
 245                                          const struct tb_port *port)
 246 {
 247         struct tb_port *down;
 248
 249         down = usb4_switch_map_usb3_down(sw, port);
 250         if (down && !tb_usb3_port_is_enabled(down))
 251                 return down;
 252         return NULL;
 253 }
 254
 255 static struct tb_tunnel *tb_find_tunnel(struct tb *tb, enum tb_tunnel_type type,
 256                                         struct tb_port *src_port,
 257                                         struct tb_port *dst_port)
 258 {
 259         struct tb_cm *tcm = tb_priv(tb);
 260         struct tb_tunnel *tunnel;
 261
 262         list_for_each_entry(tunnel, &tcm->tunnel_list, list) {
 263                 if (tunnel->type == type &&
 264                     ((src_port && src_port == tunnel->src_port) ||
 265                      (dst_port && dst_port == tunnel->dst_port))) {
 266                         return tunnel;
 267                 }
 268         }
 269
 270         return NULL;
 271 }
 272
 273 static struct tb_tunnel *tb_find_first_usb3_tunnel(struct tb *tb,
 274                                                    struct tb_port *src_port,
 275                                                    struct tb_port *dst_port)
 276 {
 277         struct tb_port *port, *usb3_down;
 278         struct tb_switch *sw;
 279
 280         /* Pick the router that is deepest in the topology */
 281         if (dst_port->sw->config.depth > src_port->sw->config.depth)
 282                 sw = dst_port->sw;
 283         else
 284                 sw = src_port->sw;
 285
 286         /* Can't be the host router */
 287         if (sw == tb->root_switch)
 288                 return NULL;
 289
 290         /* Find the downstream USB4 port that leads to this router */
 291         port = tb_port_at(tb_route(sw), tb->root_switch);
 292         /* Find the corresponding host router USB3 downstream port */
 293         usb3_down = usb4_switch_map_usb3_down(tb->root_switch, port);
 294         if (!usb3_down)
 295                 return NULL;
 296
 297         return tb_find_tunnel(tb, TB_TUNNEL_USB3, usb3_down, NULL);
 298 }
 299
 300 static int tb_available_bandwidth(struct tb *tb, struct tb_port *src_port,
 301         struct tb_port *dst_port, int *available_up, int *available_down)
 302 {
 303         int usb3_consumed_up, usb3_consumed_down, ret;
 304         struct tb_cm *tcm = tb_priv(tb);
 305         struct tb_tunnel *tunnel;
 306         struct tb_port *port;
 307
 308         tb_port_dbg(dst_port, "calculating available bandwidth\n");
 309
 310         tunnel = tb_find_first_usb3_tunnel(tb, src_port, dst_port);
 311         if (tunnel) {
 312                 ret = tb_tunnel_consumed_bandwidth(tunnel, &usb3_consumed_up,
 313                                                    &usb3_consumed_down);
 314                 if (ret)
 315                         return ret;
 316         } else {
 317                 usb3_consumed_up = 0;
 318                 usb3_consumed_down = 0;
 319         }
 320
 321         *available_up = *available_down = 40000;
 322
 323         /* Find the minimum available bandwidth over all links */
 324         tb_for_each_port_on_path(src_port, dst_port, port) {
 325                 int link_speed, link_width, up_bw, down_bw;
 326
 327                 if (!tb_port_is_null(port))
 328                         continue;
 329
 330                 if (tb_is_upstream_port(port)) {
 331                         link_speed = port->sw->link_speed;
 332                 } else {
 333                         link_speed = tb_port_get_link_speed(port);
 334                         if (link_speed < 0)
 335                                 return link_speed;
 336                 }
 337
 338                 link_width = port->bonded ? 2 : 1;
 339
 340                 up_bw = link_speed * link_width * 1000; /* Mb/s */
 341                 /* Leave 10% guard band */
 342                 up_bw -= up_bw / 10;
 343                 down_bw = up_bw;
 344
 345                 tb_port_dbg(port, "link total bandwidth %d Mb/s\n", up_bw);
 346
 347                 /*
 348                  * Find all DP tunnels that cross the port and reduce
 349                  * their consumed bandwidth from the available.
 350                  */
 351                 list_for_each_entry(tunnel, &tcm->tunnel_list, list) {
 352                         int dp_consumed_up, dp_consumed_down;
 353
 354                         if (!tb_tunnel_is_dp(tunnel))
 355                                 continue;
 356
 357                         if (!tb_tunnel_port_on_path(tunnel, port))
 358                                 continue;
 359
 360                         ret = tb_tunnel_consumed_bandwidth(tunnel,
 361                                                            &dp_consumed_up,
 362                                                            &dp_consumed_down);
 363                         if (ret)
 364                                 return ret;
 365
 366                         up_bw -= dp_consumed_up;
 367                         down_bw -= dp_consumed_down;
 368                 }
 369
 370                 /*
 371                  * If USB3 is tunneled from the host router down to the
 372                  * branch leading to port we need to take USB3 consumed
 373                  * bandwidth into account regardless whether it actually
 374                  * crosses the port.
 375                  */
 376                 up_bw -= usb3_consumed_up;
 377                 down_bw -= usb3_consumed_down;
 378
 379                 if (up_bw < *available_up)
 380                         *available_up = up_bw;
 381                 if (down_bw < *available_down)
 382                         *available_down = down_bw;
 383         }
 384
 385         if (*available_up < 0)
 386                 *available_up = 0;
 387         if (*available_down < 0)
 388                 *available_down = 0;
 389
 390         return 0;
 391 }
 392
 393 static int tb_release_unused_usb3_bandwidth(struct tb *tb,
 394                                             struct tb_port *src_port,
 395                                             struct tb_port *dst_port)
 396 {
 397         struct tb_tunnel *tunnel;
 398
 399         tunnel = tb_find_first_usb3_tunnel(tb, src_port, dst_port);
 400         return tunnel ? tb_tunnel_release_unused_bandwidth(tunnel) : 0;
 401 }
 402
 403 static void tb_reclaim_usb3_bandwidth(struct tb *tb, struct tb_port *src_port,
 404                                       struct tb_port *dst_port)
 405 {
 406         int ret, available_up, available_down;
 407         struct tb_tunnel *tunnel;
 408
 409         tunnel = tb_find_first_usb3_tunnel(tb, src_port, dst_port);
 410         if (!tunnel)
 411                 return;
 412
 413         tb_dbg(tb, "reclaiming unused bandwidth for USB3\n");
 414
 415         /*
 416          * Calculate available bandwidth for the first hop USB3 tunnel.
 417          * That determines the whole USB3 bandwidth for this branch.
 418          */
 419         ret = tb_available_bandwidth(tb, tunnel->src_port, tunnel->dst_port,
 420                                      &available_up, &available_down);
 421         if (ret) {
 422                 tb_warn(tb, "failed to calculate available bandwidth\n");
 423                 return;
 424         }
 425
 426         tb_dbg(tb, "available bandwidth for USB3 %d/%d Mb/s\n",
 427                available_up, available_down);
 428
 429         tb_tunnel_reclaim_available_bandwidth(tunnel, &available_up, &available_down);
 430 }
 431
 432 static int tb_tunnel_usb3(struct tb *tb, struct tb_switch *sw)
 433 {
 434         struct tb_switch *parent = tb_switch_parent(sw);
 435         int ret, available_up, available_down;
 436         struct tb_port *up, *down, *port;
 437         struct tb_cm *tcm = tb_priv(tb);
 438         struct tb_tunnel *tunnel;
 439
 440         if (!tb_acpi_may_tunnel_usb3()) {
 441                 tb_dbg(tb, "USB3 tunneling disabled, not creating tunnel\n");
 442                 return 0;
 443         }
 444
 445         up = tb_switch_find_port(sw, TB_TYPE_USB3_UP);
 446         if (!up)
 447                 return 0;
 448
 449         if (!sw->link_usb4)
 450                 return 0;
 451
 452         /*
 453          * Look up available down port. Since we are chaining it should
 454          * be found right above this switch.
 455          */
 456         port = tb_port_at(tb_route(sw), parent);
 457         down = tb_find_usb3_down(parent, port);
 458         if (!down)
 459                 return 0;
 460
 461         if (tb_route(parent)) {
 462                 struct tb_port *parent_up;
 463                 /*
 464                  * Check first that the parent switch has its upstream USB3
 465                  * port enabled. Otherwise the chain is not complete and
 466                  * there is no point setting up a new tunnel.
 467                  */
 468                 parent_up = tb_switch_find_port(parent, TB_TYPE_USB3_UP);
 469                 if (!parent_up || !tb_port_is_enabled(parent_up))
 470                         return 0;
 471
 472                 /* Make all unused bandwidth available for the new tunnel */
 473                 ret = tb_release_unused_usb3_bandwidth(tb, down, up);
 474                 if (ret)
 475                         return ret;
 476         }
 477
 478         ret = tb_available_bandwidth(tb, down, up, &available_up,
 479                                      &available_down);
 480         if (ret)
 481                 goto err_reclaim;
 482
 483         tb_port_dbg(up, "available bandwidth for new USB3 tunnel %d/%d Mb/s\n",
 484                     available_up, available_down);
 485
 486         tunnel = tb_tunnel_alloc_usb3(tb, up, down, available_up,
 487                                       available_down);
 488         if (!tunnel) {
 489                 ret = -ENOMEM;
 490                 goto err_reclaim;
 491         }
 492
 493         if (tb_tunnel_activate(tunnel)) {
 494                 tb_port_info(up,
 495                              "USB3 tunnel activation failed, aborting\n");
 496                 ret = -EIO;
 497                 goto err_free;
 498         }
 499
 500         list_add_tail(&tunnel->list, &tcm->tunnel_list);
 501         if (tb_route(parent))
 502                 tb_reclaim_usb3_bandwidth(tb, down, up);
 503
 504         return 0;
 505
 506 err_free:
 507         tb_tunnel_free(tunnel);
 508 err_reclaim:
 509         if (tb_route(parent))
 510                 tb_reclaim_usb3_bandwidth(tb, down, up);
 511
 512         return ret;
 513 }
 514
 515 static int tb_create_usb3_tunnels(struct tb_switch *sw)
 516 {
 517         struct tb_port *port;
 518         int ret;
 519
 520         if (!tb_acpi_may_tunnel_usb3())
 521                 return 0;
 522
 523         if (tb_route(sw)) {
 524                 ret = tb_tunnel_usb3(sw->tb, sw);
 525                 if (ret)
 526                         return ret;
 527         }
 528
 529         tb_switch_for_each_port(sw, port) {
 530                 if (!tb_port_has_remote(port))
 531                         continue;
 532                 ret = tb_create_usb3_tunnels(port->remote->sw);
 533                 if (ret)
 534                         return ret;
 535         }
 536
 537         return 0;
 538 }
 539
 540 static void tb_scan_port(struct tb_port *port);
 541
 542 /*
 543  * tb_scan_switch() - scan for and initialize downstream switches
 544  */
 545 static void tb_scan_switch(struct tb_switch *sw)
 546 {
 547         struct tb_port *port;
 548
 549         pm_runtime_get_sync(&sw->dev);
 550
 551         tb_switch_for_each_port(sw, port)
 552                 tb_scan_port(port);
 553
 554         pm_runtime_mark_last_busy(&sw->dev);
 555         pm_runtime_put_autosuspend(&sw->dev);
 556 }
 557
 558 /*
 559  * tb_scan_port() - check for and initialize switches below port
 560  */
 561 static void tb_scan_port(struct tb_port *port)
 562 {
 563         struct tb_cm *tcm = tb_priv(port->sw->tb);
 564         struct tb_port *upstream_port;
 565         struct tb_switch *sw;
 566
 567         if (tb_is_upstream_port(port))
 568                 return;
 569
 570         if (tb_port_is_dpout(port) && tb_dp_port_hpd_is_active(port) == 1 &&
 571             !tb_dp_port_is_enabled(port)) {
 572                 tb_port_dbg(port, "DP adapter HPD set, queuing hotplug\n");
 573                 tb_queue_hotplug(port->sw->tb, tb_route(port->sw), port->port,
 574                                  false);
 575                 return;
 576         }
 577
 578         if (port->config.type != TB_TYPE_PORT)
 579                 return;
 580         if (port->dual_link_port && port->link_nr)
 581                 return; /*
 582                          * Downstream switch is reachable through two ports.
 583                          * Only scan on the primary port (link_nr == 0).
 584                          */
 585         if (tb_wait_for_port(port, false) <= 0)
 586                 return;
 587         if (port->remote) {
 588                 tb_port_dbg(port, "port already has a remote\n");
 589                 return;
 590         }
 591
 592         tb_retimer_scan(port);
 593
 594         sw = tb_switch_alloc(port->sw->tb, &port->sw->dev,
 595                              tb_downstream_route(port));
 596         if (IS_ERR(sw)) {
 597                 /*
 598                  * If there is an error accessing the connected switch
 599                  * it may be connected to another domain. Also we allow
 600                  * the other domain to be connected to a max depth switch.
 601                  */
 602                 if (PTR_ERR(sw) == -EIO || PTR_ERR(sw) == -EADDRNOTAVAIL)
 603                         tb_scan_xdomain(port);
 604                 return;
 605         }
 606
 607         if (tb_switch_configure(sw)) {
 608                 tb_switch_put(sw);
 609                 return;
 610         }
 611
 612         /*
 613          * If there was previously another domain connected remove it
 614          * first.
 615          */
 616         if (port->xdomain) {
 617                 tb_xdomain_remove(port->xdomain);
 618                 tb_port_unconfigure_xdomain(port);
 619                 port->xdomain = NULL;
 620         }
 621
 622         /*
 623          * Do not send uevents until we have discovered all existing
 624          * tunnels and know which switches were authorized already by
 625          * the boot firmware.
 626          */
 627         if (!tcm->hotplug_active)
 628                 dev_set_uevent_suppress(&sw->dev, true);
 629
 630         /*
 631          * At the moment Thunderbolt 2 and beyond (devices with LC) we
 632          * can support runtime PM.
 633          */
 634         sw->rpm = sw->generation > 1;
 635
 636         if (tb_switch_add(sw)) {
 637                 tb_switch_put(sw);
 638                 return;
 639         }
 640
 641         /* Link the switches using both links if available */
 642         upstream_port = tb_upstream_port(sw);
 643         port->remote = upstream_port;
 644         upstream_port->remote = port;
 645         if (port->dual_link_port && upstream_port->dual_link_port) {
 646                 port->dual_link_port->remote = upstream_port->dual_link_port;
 647                 upstream_port->dual_link_port->remote = port->dual_link_port;
 648         }
 649
 650         /* Enable lane bonding if supported */
 651         tb_switch_lane_bonding_enable(sw);
 652         /* Set the link configured */
 653         tb_switch_configure_link(sw);
 654
 655         if (tb_enable_tmu(sw))
 656                 tb_sw_warn(sw, "failed to enable TMU\n");
 657
 658         /* Scan upstream retimers */
 659         tb_retimer_scan(upstream_port);
 660
 661         /*
 662          * Create USB 3.x tunnels only when the switch is plugged to the
 663          * domain. This is because we scan the domain also during discovery
 664          * and want to discover existing USB 3.x tunnels before we create
 665          * any new.
 666          */
 667         if (tcm->hotplug_active && tb_tunnel_usb3(sw->tb, sw))
 668                 tb_sw_warn(sw, "USB3 tunnel creation failed\n");
 669
 670         tb_add_dp_resources(sw);
 671         tb_scan_switch(sw);
 672 }
 673
 674 static void tb_deactivate_and_free_tunnel(struct tb_tunnel *tunnel)
 675 {
 676         struct tb_port *src_port, *dst_port;
 677         struct tb *tb;
 678
 679         if (!tunnel)
 680                 return;
 681
 682         tb_tunnel_deactivate(tunnel);
 683         list_del(&tunnel->list);
 684
 685         tb = tunnel->tb;
 686         src_port = tunnel->src_port;
 687         dst_port = tunnel->dst_port;
 688
 689         switch (tunnel->type) {
 690         case TB_TUNNEL_DP:
 691                 /*
 692                  * In case of DP tunnel make sure the DP IN resource is
 693                  * deallocated properly.
 694                  */
 695                 tb_switch_dealloc_dp_resource(src_port->sw, src_port);
 696                 /* Now we can allow the domain to runtime suspend again */
 697                 pm_runtime_mark_last_busy(&dst_port->sw->dev);
 698                 pm_runtime_put_autosuspend(&dst_port->sw->dev);
 699                 pm_runtime_mark_last_busy(&src_port->sw->dev);
 700                 pm_runtime_put_autosuspend(&src_port->sw->dev);
 701                 fallthrough;
 702
 703         case TB_TUNNEL_USB3:
 704                 tb_reclaim_usb3_bandwidth(tb, src_port, dst_port);
 705                 break;
 706
 707         default:
 708                 /*
 709                  * PCIe and DMA tunnels do not consume guaranteed
 710                  * bandwidth.
 711                  */
 712                 break;
 713         }
 714
 715         tb_tunnel_free(tunnel);
 716 }
 717
 718 /*
 719  * tb_free_invalid_tunnels() - destroy tunnels of devices that have gone away
 720  */
 721 static void tb_free_invalid_tunnels(struct tb *tb)
 722 {
 723         struct tb_cm *tcm = tb_priv(tb);
 724         struct tb_tunnel *tunnel;
 725         struct tb_tunnel *n;
 726
 727         list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) {
 728                 if (tb_tunnel_is_invalid(tunnel))
 729                         tb_deactivate_and_free_tunnel(tunnel);
 730         }
 731 }
 732
 733 /*
 734  * tb_free_unplugged_children() - traverse hierarchy and free unplugged switches
 735  */
 736 static void tb_free_unplugged_children(struct tb_switch *sw)
 737 {
 738         struct tb_port *port;
 739
 740         tb_switch_for_each_port(sw, port) {
 741                 if (!tb_port_has_remote(port))
 742                         continue;
 743
 744                 if (port->remote->sw->is_unplugged) {
 745                         tb_retimer_remove_all(port);
 746                         tb_remove_dp_resources(port->remote->sw);
 747                         tb_switch_unconfigure_link(port->remote->sw);
 748                         tb_switch_lane_bonding_disable(port->remote->sw);
 749                         tb_switch_remove(port->remote->sw);
 750                         port->remote = NULL;
 751                         if (port->dual_link_port)
 752                                 port->dual_link_port->remote = NULL;
 753                 } else {
 754                         tb_free_unplugged_children(port->remote->sw);
 755                 }
 756         }
 757 }
 758
 759 static struct tb_port *tb_find_pcie_down(struct tb_switch *sw,
 760                                          const struct tb_port *port)
 761 {
 762         struct tb_port *down = NULL;
 763
 764         /*
 765          * To keep plugging devices consistently in the same PCIe
 766          * hierarchy, do mapping here for switch downstream PCIe ports.
 767          */
 768         if (tb_switch_is_usb4(sw)) {
 769                 down = usb4_switch_map_pcie_down(sw, port);
 770         } else if (!tb_route(sw)) {
 771                 int phy_port = tb_phy_port_from_link(port->port);
 772                 int index;
 773
 774                 /*
 775                  * Hard-coded Thunderbolt port to PCIe down port mapping
 776                  * per controller.
 777                  */
 778                 if (tb_switch_is_cactus_ridge(sw) ||
 779                     tb_switch_is_alpine_ridge(sw))
 780                         index = !phy_port ? 6 : 7;
 781                 else if (tb_switch_is_falcon_ridge(sw))
 782                         index = !phy_port ? 6 : 8;
 783                 else if (tb_switch_is_titan_ridge(sw))
 784                         index = !phy_port ? 8 : 9;
 785                 else
 786                         goto out;
 787
 788                 /* Validate the hard-coding */
 789                 if (WARN_ON(index > sw->config.max_port_number))
 790                         goto out;
 791
 792                 down = &sw->ports[index];
 793         }
 794
 795         if (down) {
 796                 if (WARN_ON(!tb_port_is_pcie_down(down)))
 797                         goto out;
 798                 if (tb_pci_port_is_enabled(down))
 799                         goto out;
 800
 801                 return down;
 802         }
 803
 804 out:
 805         return tb_find_unused_port(sw, TB_TYPE_PCIE_DOWN);
 806 }
 807
 808 static struct tb_port *tb_find_dp_out(struct tb *tb, struct tb_port *in)
 809 {
 810         struct tb_port *host_port, *port;
 811         struct tb_cm *tcm = tb_priv(tb);
 812
 813         host_port = tb_route(in->sw) ?
 814                 tb_port_at(tb_route(in->sw), tb->root_switch) : NULL;
 815
 816         list_for_each_entry(port, &tcm->dp_resources, list) {
 817                 if (!tb_port_is_dpout(port))
 818                         continue;
 819
 820                 if (tb_port_is_enabled(port)) {
 821                         tb_port_dbg(port, "in use\n");
 822                         continue;
 823                 }
 824
 825                 tb_port_dbg(port, "DP OUT available\n");
 826
 827                 /*
 828                  * Keep the DP tunnel under the topology starting from
 829                  * the same host router downstream port.
 830                  */
 831                 if (host_port && tb_route(port->sw)) {
 832                         struct tb_port *p;
 833
 834                         p = tb_port_at(tb_route(port->sw), tb->root_switch);
 835                         if (p != host_port)
 836                                 continue;
 837                 }
 838
 839                 return port;
 840         }
 841
 842         return NULL;
 843 }
 844
 845 static void tb_tunnel_dp(struct tb *tb)
 846 {
 847         int available_up, available_down, ret;
 848         struct tb_cm *tcm = tb_priv(tb);
 849         struct tb_port *port, *in, *out;
 850         struct tb_tunnel *tunnel;
 851
 852         if (!tb_acpi_may_tunnel_dp()) {
 853                 tb_dbg(tb, "DP tunneling disabled, not creating tunnel\n");
 854                 return;
 855         }
 856
 857         /*
 858          * Find pair of inactive DP IN and DP OUT adapters and then
 859          * establish a DP tunnel between them.
 860          */
 861         tb_dbg(tb, "looking for DP IN <-> DP OUT pairs:\n");
 862
 863         in = NULL;
 864         out = NULL;
 865         list_for_each_entry(port, &tcm->dp_resources, list) {
 866                 if (!tb_port_is_dpin(port))
 867                         continue;
 868
 869                 if (tb_port_is_enabled(port)) {
 870                         tb_port_dbg(port, "in use\n");
 871                         continue;
 872                 }
 873
 874                 tb_port_dbg(port, "DP IN available\n");
 875
 876                 out = tb_find_dp_out(tb, port);
 877                 if (out) {
 878                         in = port;
 879                         break;
 880                 }
 881         }
 882
 883         if (!in) {
 884                 tb_dbg(tb, "no suitable DP IN adapter available, not tunneling\n");
 885                 return;
 886         }
 887         if (!out) {
 888                 tb_dbg(tb, "no suitable DP OUT adapter available, not tunneling\n");
 889                 return;
 890         }
 891
 892         /*
 893          * DP stream needs the domain to be active so runtime resume
 894          * both ends of the tunnel.
 895          *
 896          * This should bring the routers in the middle active as well
 897          * and keeps the domain from runtime suspending while the DP
 898          * tunnel is active.
 899          */
 900         pm_runtime_get_sync(&in->sw->dev);
 901         pm_runtime_get_sync(&out->sw->dev);
 902
 903         if (tb_switch_alloc_dp_resource(in->sw, in)) {
 904                 tb_port_dbg(in, "no resource available for DP IN, not tunneling\n");
 905                 goto err_rpm_put;
 906         }
 907
 908         /* Make all unused USB3 bandwidth available for the new DP tunnel */
 909         ret = tb_release_unused_usb3_bandwidth(tb, in, out);
 910         if (ret) {
 911                 tb_warn(tb, "failed to release unused bandwidth\n");
 912                 goto err_dealloc_dp;
 913         }
 914
 915         ret = tb_available_bandwidth(tb, in, out, &available_up,
 916                                      &available_down);
 917         if (ret)
 918                 goto err_reclaim;
 919
 920         tb_dbg(tb, "available bandwidth for new DP tunnel %u/%u Mb/s\n",
 921                available_up, available_down);
 922
 923         tunnel = tb_tunnel_alloc_dp(tb, in, out, available_up, available_down);
 924         if (!tunnel) {
 925                 tb_port_dbg(out, "could not allocate DP tunnel\n");
 926                 goto err_reclaim;
 927         }
 928
 929         if (tb_tunnel_activate(tunnel)) {
 930                 tb_port_info(out, "DP tunnel activation failed, aborting\n");
 931                 goto err_free;
 932         }
 933
 934         list_add_tail(&tunnel->list, &tcm->tunnel_list);
 935         tb_reclaim_usb3_bandwidth(tb, in, out);
 936         return;
 937
 938 err_free:
 939         tb_tunnel_free(tunnel);
 940 err_reclaim:
 941         tb_reclaim_usb3_bandwidth(tb, in, out);
 942 err_dealloc_dp:
 943         tb_switch_dealloc_dp_resource(in->sw, in);
 944 err_rpm_put:
 945         pm_runtime_mark_last_busy(&out->sw->dev);
 946         pm_runtime_put_autosuspend(&out->sw->dev);
 947         pm_runtime_mark_last_busy(&in->sw->dev);
 948         pm_runtime_put_autosuspend(&in->sw->dev);
 949 }
 950
 951 static void tb_dp_resource_unavailable(struct tb *tb, struct tb_port *port)
 952 {
 953         struct tb_port *in, *out;
 954         struct tb_tunnel *tunnel;
 955
 956         if (tb_port_is_dpin(port)) {
 957                 tb_port_dbg(port, "DP IN resource unavailable\n");
 958                 in = port;
 959                 out = NULL;
 960         } else {
 961                 tb_port_dbg(port, "DP OUT resource unavailable\n");
 962                 in = NULL;
 963                 out = port;
 964         }
 965
 966         tunnel = tb_find_tunnel(tb, TB_TUNNEL_DP, in, out);
 967         tb_deactivate_and_free_tunnel(tunnel);
 968         list_del_init(&port->list);
 969
 970         /*
 971          * See if there is another DP OUT port that can be used for
 972          * to create another tunnel.
 973          */
 974         tb_tunnel_dp(tb);
 975 }
 976
 977 static void tb_dp_resource_available(struct tb *tb, struct tb_port *port)
 978 {
 979         struct tb_cm *tcm = tb_priv(tb);
 980         struct tb_port *p;
 981
 982         if (tb_port_is_enabled(port))
 983                 return;
 984
 985         list_for_each_entry(p, &tcm->dp_resources, list) {
 986                 if (p == port)
 987                         return;
 988         }
 989
 990         tb_port_dbg(port, "DP %s resource available\n",
 991                     tb_port_is_dpin(port) ? "IN" : "OUT");
 992         list_add_tail(&port->list, &tcm->dp_resources);
 993
 994         /* Look for suitable DP IN <-> DP OUT pairs now */
 995         tb_tunnel_dp(tb);
 996 }
 997
 998 static void tb_disconnect_and_release_dp(struct tb *tb)
 999 {
1000         struct tb_cm *tcm = tb_priv(tb);
1001         struct tb_tunnel *tunnel, *n;
1002
1003         /*
1004          * Tear down all DP tunnels and release their resources. They
1005          * will be re-established after resume based on plug events.
1006          */
1007         list_for_each_entry_safe_reverse(tunnel, n, &tcm->tunnel_list, list) {
1008                 if (tb_tunnel_is_dp(tunnel))
1009                         tb_deactivate_and_free_tunnel(tunnel);
1010         }
1011
1012         while (!list_empty(&tcm->dp_resources)) {
1013                 struct tb_port *port;
1014
1015                 port = list_first_entry(&tcm->dp_resources,
1016                                         struct tb_port, list);
1017                 list_del_init(&port->list);
1018         }
1019 }
1020
1021 static int tb_disconnect_pci(struct tb *tb, struct tb_switch *sw)
1022 {
1023         struct tb_tunnel *tunnel;
1024         struct tb_port *up;
1025
1026         up = tb_switch_find_port(sw, TB_TYPE_PCIE_UP);
1027         if (WARN_ON(!up))
1028                 return -ENODEV;
1029
1030         tunnel = tb_find_tunnel(tb, TB_TUNNEL_PCI, NULL, up);
1031         if (WARN_ON(!tunnel))
1032                 return -ENODEV;
1033
1034         tb_tunnel_deactivate(tunnel);
1035         list_del(&tunnel->list);
1036         tb_tunnel_free(tunnel);
1037         return 0;
1038 }
1039
1040 static int tb_tunnel_pci(struct tb *tb, struct tb_switch *sw)
1041 {
1042         struct tb_port *up, *down, *port;
1043         struct tb_cm *tcm = tb_priv(tb);
1044         struct tb_switch *parent_sw;
1045         struct tb_tunnel *tunnel;
1046
1047         up = tb_switch_find_port(sw, TB_TYPE_PCIE_UP);
1048         if (!up)
1049                 return 0;
1050
1051         /*
1052          * Look up available down port. Since we are chaining it should
1053          * be found right above this switch.
1054          */
1055         parent_sw = tb_to_switch(sw->dev.parent);
1056         port = tb_port_at(tb_route(sw), parent_sw);
1057         down = tb_find_pcie_down(parent_sw, port);
1058         if (!down)
1059                 return 0;
1060
1061         tunnel = tb_tunnel_alloc_pci(tb, up, down);
1062         if (!tunnel)
1063                 return -ENOMEM;
1064
1065         if (tb_tunnel_activate(tunnel)) {
1066                 tb_port_info(up,
1067                              "PCIe tunnel activation failed, aborting\n");
1068                 tb_tunnel_free(tunnel);
1069                 return -EIO;
1070         }
1071
1072         list_add_tail(&tunnel->list, &tcm->tunnel_list);
1073         return 0;
1074 }
1075
1076 static int tb_approve_xdomain_paths(struct tb *tb, struct tb_xdomain *xd)
1077 {
1078         struct tb_cm *tcm = tb_priv(tb);
1079         struct tb_port *nhi_port, *dst_port;
1080         struct tb_tunnel *tunnel;
1081         struct tb_switch *sw;
1082
1083         sw = tb_to_switch(xd->dev.parent);
1084         dst_port = tb_port_at(xd->route, sw);
1085         nhi_port = tb_switch_find_port(tb->root_switch, TB_TYPE_NHI);
1086
1087         mutex_lock(&tb->lock);
1088         tunnel = tb_tunnel_alloc_dma(tb, nhi_port, dst_port, xd->transmit_ring,
1089                                      xd->transmit_path, xd->receive_ring,
1090                                      xd->receive_path);
1091         if (!tunnel) {
1092                 mutex_unlock(&tb->lock);
1093                 return -ENOMEM;
1094         }
1095
1096         if (tb_tunnel_activate(tunnel)) {
1097                 tb_port_info(nhi_port,
1098                              "DMA tunnel activation failed, aborting\n");
1099                 tb_tunnel_free(tunnel);
1100                 mutex_unlock(&tb->lock);
1101                 return -EIO;
1102         }
1103
1104         list_add_tail(&tunnel->list, &tcm->tunnel_list);
1105         mutex_unlock(&tb->lock);
1106         return 0;
1107 }
1108
1109 static void __tb_disconnect_xdomain_paths(struct tb *tb, struct tb_xdomain *xd)
1110 {
1111         struct tb_port *dst_port;
1112         struct tb_tunnel *tunnel;
1113         struct tb_switch *sw;
1114
1115         sw = tb_to_switch(xd->dev.parent);
1116         dst_port = tb_port_at(xd->route, sw);
1117
1118         /*
1119          * It is possible that the tunnel was already teared down (in
1120          * case of cable disconnect) so it is fine if we cannot find it
1121          * here anymore.
1122          */
1123         tunnel = tb_find_tunnel(tb, TB_TUNNEL_DMA, NULL, dst_port);
1124         tb_deactivate_and_free_tunnel(tunnel);
1125 }
1126
1127 static int tb_disconnect_xdomain_paths(struct tb *tb, struct tb_xdomain *xd)
1128 {
1129         if (!xd->is_unplugged) {
1130                 mutex_lock(&tb->lock);
1131                 __tb_disconnect_xdomain_paths(tb, xd);
1132                 mutex_unlock(&tb->lock);
1133         }
1134         return 0;
1135 }
1136
1137 /* hotplug handling */
1138
1139 /*
1140  * tb_handle_hotplug() - handle hotplug event
1141  *
1142  * Executes on tb->wq.
1143  */
1144 static void tb_handle_hotplug(struct work_struct *work)
1145 {
1146         struct tb_hotplug_event *ev = container_of(work, typeof(*ev), work);
1147         struct tb *tb = ev->tb;
1148         struct tb_cm *tcm = tb_priv(tb);
1149         struct tb_switch *sw;
1150         struct tb_port *port;
1151
1152         /* Bring the domain back from sleep if it was suspended */
1153         pm_runtime_get_sync(&tb->dev);
1154
1155         mutex_lock(&tb->lock);
1156         if (!tcm->hotplug_active)
1157                 goto out; /* during init, suspend or shutdown */
1158
1159         sw = tb_switch_find_by_route(tb, ev->route);
1160         if (!sw) {
1161                 tb_warn(tb,
1162                         "hotplug event from non existent switch %llx:%x (unplug: %d)\n",
1163                         ev->route, ev->port, ev->unplug);
1164                 goto out;
1165         }
1166         if (ev->port > sw->config.max_port_number) {
1167                 tb_warn(tb,
1168                         "hotplug event from non existent port %llx:%x (unplug: %d)\n",
1169                         ev->route, ev->port, ev->unplug);
1170                 goto put_sw;
1171         }
1172         port = &sw->ports[ev->port];
1173         if (tb_is_upstream_port(port)) {
1174                 tb_dbg(tb, "hotplug event for upstream port %llx:%x (unplug: %d)\n",
1175                        ev->route, ev->port, ev->unplug);
1176                 goto put_sw;
1177         }
1178
1179         pm_runtime_get_sync(&sw->dev);
1180
1181         if (ev->unplug) {
1182                 tb_retimer_remove_all(port);
1183
1184                 if (tb_port_has_remote(port)) {
1185                         tb_port_dbg(port, "switch unplugged\n");
1186                         tb_sw_set_unplugged(port->remote->sw);
1187                         tb_free_invalid_tunnels(tb);
1188                         tb_remove_dp_resources(port->remote->sw);
1189                         tb_switch_tmu_disable(port->remote->sw);
1190                         tb_switch_unconfigure_link(port->remote->sw);
1191                         tb_switch_lane_bonding_disable(port->remote->sw);
1192                         tb_switch_remove(port->remote->sw);
1193                         port->remote = NULL;
1194                         if (port->dual_link_port)
1195                                 port->dual_link_port->remote = NULL;
1196                         /* Maybe we can create another DP tunnel */
1197                         tb_tunnel_dp(tb);
1198                 } else if (port->xdomain) {
1199                         struct tb_xdomain *xd = tb_xdomain_get(port->xdomain);
1200
1201                         tb_port_dbg(port, "xdomain unplugged\n");
1202                         /*
1203                          * Service drivers are unbound during
1204                          * tb_xdomain_remove() so setting XDomain as
1205                          * unplugged here prevents deadlock if they call
1206                          * tb_xdomain_disable_paths(). We will tear down
1207                          * the path below.
1208                          */
1209                         xd->is_unplugged = true;
1210                         tb_xdomain_remove(xd);
1211                         port->xdomain = NULL;
1212                         __tb_disconnect_xdomain_paths(tb, xd);
1213                         tb_xdomain_put(xd);
1214                         tb_port_unconfigure_xdomain(port);
1215                 } else if (tb_port_is_dpout(port) || tb_port_is_dpin(port)) {
1216                         tb_dp_resource_unavailable(tb, port);
1217                 } else {
1218                         tb_port_dbg(port,
1219                                    "got unplug event for disconnected port, ignoring\n");
1220                 }
1221         } else if (port->remote) {
1222                 tb_port_dbg(port, "got plug event for connected port, ignoring\n");
1223         } else {
1224                 if (tb_port_is_null(port)) {
1225                         tb_port_dbg(port, "hotplug: scanning\n");
1226                         tb_scan_port(port);
1227                         if (!port->remote)
1228                                 tb_port_dbg(port, "hotplug: no switch found\n");
1229                 } else if (tb_port_is_dpout(port) || tb_port_is_dpin(port)) {
1230                         tb_dp_resource_available(tb, port);
1231                 }
1232         }
1233
1234         pm_runtime_mark_last_busy(&sw->dev);
1235         pm_runtime_put_autosuspend(&sw->dev);
1236
1237 put_sw:
1238         tb_switch_put(sw);
1239 out:
1240         mutex_unlock(&tb->lock);
1241
1242         pm_runtime_mark_last_busy(&tb->dev);
1243         pm_runtime_put_autosuspend(&tb->dev);
1244
1245         kfree(ev);
1246 }
1247
1248 /*
1249  * tb_schedule_hotplug_handler() - callback function for the control channel
1250  *
1251  * Delegates to tb_handle_hotplug.
1252  */
1253 static void tb_handle_event(struct tb *tb, enum tb_cfg_pkg_type type,
1254                             const void *buf, size_t size)
1255 {
1256         const struct cfg_event_pkg *pkg = buf;
1257         u64 route;
1258
1259         if (type != TB_CFG_PKG_EVENT) {
1260                 tb_warn(tb, "unexpected event %#x, ignoring\n", type);
1261                 return;
1262         }
1263
1264         route = tb_cfg_get_route(&pkg->header);
1265
1266         if (tb_cfg_ack_plug(tb->ctl, route, pkg->port, pkg->unplug)) {
1267                 tb_warn(tb, "could not ack plug event on %llx:%x\n", route,
1268                         pkg->port);
1269         }
1270
1271         tb_queue_hotplug(tb, route, pkg->port, pkg->unplug);
1272 }
1273
1274 static void tb_stop(struct tb *tb)
1275 {
1276         struct tb_cm *tcm = tb_priv(tb);
1277         struct tb_tunnel *tunnel;
1278         struct tb_tunnel *n;
1279
1280         cancel_delayed_work(&tcm->remove_work);
1281         /* tunnels are only present after everything has been initialized */
1282         list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) {
1283                 /*
1284                  * DMA tunnels require the driver to be functional so we
1285                  * tear them down. Other protocol tunnels can be left
1286                  * intact.
1287                  */
1288                 if (tb_tunnel_is_dma(tunnel))
1289                         tb_tunnel_deactivate(tunnel);
1290                 tb_tunnel_free(tunnel);
1291         }
1292         tb_switch_remove(tb->root_switch);
1293         tcm->hotplug_active = false; /* signal tb_handle_hotplug to quit */
1294 }
1295
1296 static int tb_scan_finalize_switch(struct device *dev, void *data)
1297 {
1298         if (tb_is_switch(dev)) {
1299                 struct tb_switch *sw = tb_to_switch(dev);
1300
1301                 /*
1302                  * If we found that the switch was already setup by the
1303                  * boot firmware, mark it as authorized now before we
1304                  * send uevent to userspace.
1305                  */
1306                 if (sw->boot)
1307                         sw->authorized = 1;
1308
1309                 dev_set_uevent_suppress(dev, false);
1310                 kobject_uevent(&dev->kobj, KOBJ_ADD);
1311                 device_for_each_child(dev, NULL, tb_scan_finalize_switch);
1312         }
1313
1314         return 0;
1315 }
1316
1317 static int tb_start(struct tb *tb)
1318 {
1319         struct tb_cm *tcm = tb_priv(tb);
1320         int ret;
1321
1322         tb->root_switch = tb_switch_alloc(tb, &tb->dev, 0);
1323         if (IS_ERR(tb->root_switch))
1324                 return PTR_ERR(tb->root_switch);
1325
1326         /*
1327          * ICM firmware upgrade needs running firmware and in native
1328          * mode that is not available so disable firmware upgrade of the
1329          * root switch.
1330          */
1331         tb->root_switch->no_nvm_upgrade = true;
1332         /* All USB4 routers support runtime PM */
1333         tb->root_switch->rpm = tb_switch_is_usb4(tb->root_switch);
1334
1335         ret = tb_switch_configure(tb->root_switch);
1336         if (ret) {
1337                 tb_switch_put(tb->root_switch);
1338                 return ret;
1339         }
1340
1341         /* Announce the switch to the world */
1342         ret = tb_switch_add(tb->root_switch);
1343         if (ret) {
1344                 tb_switch_put(tb->root_switch);
1345                 return ret;
1346         }
1347
1348         /* Enable TMU if it is off */
1349         tb_switch_tmu_enable(tb->root_switch);
1350         /* Full scan to discover devices added before the driver was loaded. */
1351         tb_scan_switch(tb->root_switch);
1352         /* Find out tunnels created by the boot firmware */
1353         tb_discover_tunnels(tb->root_switch);
1354         /*
1355          * If the boot firmware did not create USB 3.x tunnels create them
1356          * now for the whole topology.
1357          */
1358         tb_create_usb3_tunnels(tb->root_switch);
1359         /* Add DP IN resources for the root switch */
1360         tb_add_dp_resources(tb->root_switch);
1361         /* Make the discovered switches available to the userspace */
1362         device_for_each_child(&tb->root_switch->dev, NULL,
1363                               tb_scan_finalize_switch);
1364
1365         /* Allow tb_handle_hotplug to progress events */
1366         tcm->hotplug_active = true;
1367         return 0;
1368 }
1369
1370 static int tb_suspend_noirq(struct tb *tb)
1371 {
1372         struct tb_cm *tcm = tb_priv(tb);
1373
1374         tb_dbg(tb, "suspending...\n");
1375         tb_disconnect_and_release_dp(tb);
1376         tb_switch_suspend(tb->root_switch, false);
1377         tcm->hotplug_active = false; /* signal tb_handle_hotplug to quit */
1378         tb_dbg(tb, "suspend finished\n");
1379
1380         return 0;
1381 }
1382
1383 static void tb_restore_children(struct tb_switch *sw)
1384 {
1385         struct tb_port *port;
1386
1387         /* No need to restore if the router is already unplugged */
1388         if (sw->is_unplugged)
1389                 return;
1390
1391         if (tb_enable_tmu(sw))
1392                 tb_sw_warn(sw, "failed to restore TMU configuration\n");
1393
1394         tb_switch_for_each_port(sw, port) {
1395                 if (!tb_port_has_remote(port) && !port->xdomain)
1396                         continue;
1397
1398                 if (port->remote) {
1399                         tb_switch_lane_bonding_enable(port->remote->sw);
1400                         tb_switch_configure_link(port->remote->sw);
1401
1402                         tb_restore_children(port->remote->sw);
1403                 } else if (port->xdomain) {
1404                         tb_port_configure_xdomain(port);
1405                 }
1406         }
1407 }
1408
1409 static int tb_resume_noirq(struct tb *tb)
1410 {
1411         struct tb_cm *tcm = tb_priv(tb);
1412         struct tb_tunnel *tunnel, *n;
1413
1414         tb_dbg(tb, "resuming...\n");
1415
1416         /* remove any pci devices the firmware might have setup */
1417         tb_switch_reset(tb->root_switch);
1418
1419         tb_switch_resume(tb->root_switch);
1420         tb_free_invalid_tunnels(tb);
1421         tb_free_unplugged_children(tb->root_switch);
1422         tb_restore_children(tb->root_switch);
1423         list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list)
1424                 tb_tunnel_restart(tunnel);
1425         if (!list_empty(&tcm->tunnel_list)) {
1426                 /*
1427                  * the pcie links need some time to get going.
1428                  * 100ms works for me...
1429                  */
1430                 tb_dbg(tb, "tunnels restarted, sleeping for 100ms\n");
1431                 msleep(100);
1432         }
1433          /* Allow tb_handle_hotplug to progress events */
1434         tcm->hotplug_active = true;
1435         tb_dbg(tb, "resume finished\n");
1436
1437         return 0;
1438 }
1439
1440 static int tb_free_unplugged_xdomains(struct tb_switch *sw)
1441 {
1442         struct tb_port *port;
1443         int ret = 0;
1444
1445         tb_switch_for_each_port(sw, port) {
1446                 if (tb_is_upstream_port(port))
1447                         continue;
1448                 if (port->xdomain && port->xdomain->is_unplugged) {
1449                         tb_retimer_remove_all(port);
1450                         tb_xdomain_remove(port->xdomain);
1451                         tb_port_unconfigure_xdomain(port);
1452                         port->xdomain = NULL;
1453                         ret++;
1454                 } else if (port->remote) {
1455                         ret += tb_free_unplugged_xdomains(port->remote->sw);
1456                 }
1457         }
1458
1459         return ret;
1460 }
1461
1462 static int tb_freeze_noirq(struct tb *tb)
1463 {
1464         struct tb_cm *tcm = tb_priv(tb);
1465
1466         tcm->hotplug_active = false;
1467         return 0;
1468 }
1469
1470 static int tb_thaw_noirq(struct tb *tb)
1471 {
1472         struct tb_cm *tcm = tb_priv(tb);
1473
1474         tcm->hotplug_active = true;
1475         return 0;
1476 }
1477
1478 static void tb_complete(struct tb *tb)
1479 {
1480         /*
1481          * Release any unplugged XDomains and if there is a case where
1482          * another domain is swapped in place of unplugged XDomain we
1483          * need to run another rescan.
1484          */
1485         mutex_lock(&tb->lock);
1486         if (tb_free_unplugged_xdomains(tb->root_switch))
1487                 tb_scan_switch(tb->root_switch);
1488         mutex_unlock(&tb->lock);
1489 }
1490
1491 static int tb_runtime_suspend(struct tb *tb)
1492 {
1493         struct tb_cm *tcm = tb_priv(tb);
1494
1495         mutex_lock(&tb->lock);
1496         tb_switch_suspend(tb->root_switch, true);
1497         tcm->hotplug_active = false;
1498         mutex_unlock(&tb->lock);
1499
1500         return 0;
1501 }
1502
1503 static void tb_remove_work(struct work_struct *work)
1504 {
1505         struct tb_cm *tcm = container_of(work, struct tb_cm, remove_work.work);
1506         struct tb *tb = tcm_to_tb(tcm);
1507
1508         mutex_lock(&tb->lock);
1509         if (tb->root_switch) {
1510                 tb_free_unplugged_children(tb->root_switch);
1511                 tb_free_unplugged_xdomains(tb->root_switch);
1512         }
1513         mutex_unlock(&tb->lock);
1514 }
1515
1516 static int tb_runtime_resume(struct tb *tb)
1517 {
1518         struct tb_cm *tcm = tb_priv(tb);
1519         struct tb_tunnel *tunnel, *n;
1520
1521         mutex_lock(&tb->lock);
1522         tb_switch_resume(tb->root_switch);
1523         tb_free_invalid_tunnels(tb);
1524         tb_restore_children(tb->root_switch);
1525         list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list)
1526                 tb_tunnel_restart(tunnel);
1527         tcm->hotplug_active = true;
1528         mutex_unlock(&tb->lock);
1529
1530         /*
1531          * Schedule cleanup of any unplugged devices. Run this in a
1532          * separate thread to avoid possible deadlock if the device
1533          * removal runtime resumes the unplugged device.
1534          */
1535         queue_delayed_work(tb->wq, &tcm->remove_work, msecs_to_jiffies(50));
1536         return 0;
1537 }
1538
1539 static const struct tb_cm_ops tb_cm_ops = {
1540         .start = tb_start,
1541         .stop = tb_stop,
1542         .suspend_noirq = tb_suspend_noirq,
1543         .resume_noirq = tb_resume_noirq,
1544         .freeze_noirq = tb_freeze_noirq,
1545         .thaw_noirq = tb_thaw_noirq,
1546         .complete = tb_complete,
1547         .runtime_suspend = tb_runtime_suspend,
1548         .runtime_resume = tb_runtime_resume,
1549         .handle_event = tb_handle_event,
1550         .disapprove_switch = tb_disconnect_pci,
1551         .approve_switch = tb_tunnel_pci,
1552         .approve_xdomain_paths = tb_approve_xdomain_paths,
1553         .disconnect_xdomain_paths = tb_disconnect_xdomain_paths,
1554 };
1555
1556 struct tb *tb_probe(struct tb_nhi *nhi)
1557 {
1558         struct tb_cm *tcm;
1559         struct tb *tb;
1560
1561         tb = tb_domain_alloc(nhi, sizeof(*tcm));
1562         if (!tb)
1563                 return NULL;
1564
1565         if (tb_acpi_may_tunnel_pcie())
1566                 tb->security_level = TB_SECURITY_USER;
1567         else
1568                 tb->security_level = TB_SECURITY_NOPCIE;
1569
1570         tb->cm_ops = &tb_cm_ops;
1571
1572         tcm = tb_priv(tb);
1573         INIT_LIST_HEAD(&tcm->tunnel_list);
1574         INIT_LIST_HEAD(&tcm->dp_resources);
1575         INIT_DELAYED_WORK(&tcm->remove_work, tb_remove_work);
1576
1577         tb_dbg(tb, "using software connection manager\n");
1578
1579         return tb;
1580 }