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