drivers/thunderbolt/tb.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Thunderbolt driver - bus logic (NHI independent)
   4  *
   5  * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com>
   6  * Copyright (C) 2019, Intel Corporation
   7  */
   8
   9 #include <linux/slab.h>
  10 #include <linux/errno.h>
  11 #include <linux/delay.h>
  12 #include <linux/pm_runtime.h>
  13 #include <linux/platform_data/x86/apple.h>
  14
  15 #include "tb.h"
  16 #include "tb_regs.h"
  17 #include "tunnel.h"
  18
  19 #define TB_TIMEOUT      100 /* ms */
  20
  21 /**
  22  * struct tb_cm - Simple Thunderbolt connection manager
  23  * @tunnel_list: List of active tunnels
  24  * @dp_resources: List of available DP resources for DP tunneling
  25  * @hotplug_active: tb_handle_hotplug will stop progressing plug
  26  *                  events and exit if this is not set (it needs to
  27  *                  acquire the lock one more time). Used to drain wq
  28  *                  after cfg has been paused.
  29  * @remove_work: Work used to remove any unplugged routers after
  30  *               runtime resume
  31  */
  32 struct tb_cm {
  33         struct list_head tunnel_list;
  34         struct list_head dp_resources;
  35         bool hotplug_active;
  36         struct delayed_work remove_work;
  37 };
  38
  39 static inline struct tb *tcm_to_tb(struct tb_cm *tcm)
  40 {
  41         return ((void *)tcm - sizeof(struct tb));
  42 }
  43
  44 struct tb_hotplug_event {
  45         struct work_struct work;
  46         struct tb *tb;
  47         u64 route;
  48         u8 port;
  49         bool unplug;
  50 };
  51
  52 static void tb_handle_hotplug(struct work_struct *work);
  53
  54 static void tb_queue_hotplug(struct tb *tb, u64 route, u8 port, bool unplug)
  55 {
  56         struct tb_hotplug_event *ev;
  57
  58         ev = kmalloc(sizeof(*ev), GFP_KERNEL);
  59         if (!ev)
  60                 return;
  61
  62         ev->tb = tb;
  63         ev->route = route;
  64         ev->port = port;
  65         ev->unplug = unplug;
  66         INIT_WORK(&ev->work, tb_handle_hotplug);
  67         queue_work(tb->wq, &ev->work);
  68 }
  69
  70 /* enumeration & hot plug handling */
  71
  72 static void tb_add_dp_resources(struct tb_switch *sw)
  73 {
  74         struct tb_cm *tcm = tb_priv(sw->tb);
  75         struct tb_port *port;
  76
  77         tb_switch_for_each_port(sw, port) {
  78                 if (!tb_port_is_dpin(port))
  79                         continue;
  80
  81                 if (!tb_switch_query_dp_resource(sw, port))
  82                         continue;
  83
  84                 list_add_tail(&port->list, &tcm->dp_resources);
  85                 tb_port_dbg(port, "DP IN resource available\n");
  86         }
  87 }
  88
  89 static void tb_remove_dp_resources(struct tb_switch *sw)
  90 {
  91         struct tb_cm *tcm = tb_priv(sw->tb);
  92         struct tb_port *port, *tmp;
  93
  94         /* Clear children resources first */
  95         tb_switch_for_each_port(sw, port) {
  96                 if (tb_port_has_remote(port))
  97                         tb_remove_dp_resources(port->remote->sw);
  98         }
  99
 100         list_for_each_entry_safe(port, tmp, &tcm->dp_resources, list) {
 101                 if (port->sw == sw) {
 102                         tb_port_dbg(port, "DP OUT resource unavailable\n");
 103                         list_del_init(&port->list);
 104                 }
 105         }
 106 }
 107
 108 static void tb_switch_discover_tunnels(struct tb_switch *sw,
 109                                        struct list_head *list,
 110                                        bool alloc_hopids)
 111 {
 112         struct tb *tb = sw->tb;
 113         struct tb_port *port;
 114
 115         tb_switch_for_each_port(sw, port) {
 116                 struct tb_tunnel *tunnel = NULL;
 117
 118                 switch (port->config.type) {
 119                 case TB_TYPE_DP_HDMI_IN:
 120                         tunnel = tb_tunnel_discover_dp(tb, port, alloc_hopids);
 121                         break;
 122
 123                 case TB_TYPE_PCIE_DOWN:
 124                         tunnel = tb_tunnel_discover_pci(tb, port, alloc_hopids);
 125                         break;
 126
 127                 case TB_TYPE_USB3_DOWN:
 128                         tunnel = tb_tunnel_discover_usb3(tb, port, alloc_hopids);
 129                         break;
 130
 131                 default:
 132                         break;
 133                 }
 134
 135                 if (tunnel)
 136                         list_add_tail(&tunnel->list, list);
 137         }
 138
 139         tb_switch_for_each_port(sw, port) {
 140                 if (tb_port_has_remote(port)) {
 141                         tb_switch_discover_tunnels(port->remote->sw, list,
 142                                                    alloc_hopids);
 143                 }
 144         }
 145 }
 146
 147 static void tb_discover_tunnels(struct tb *tb)
 148 {
 149         struct tb_cm *tcm = tb_priv(tb);
 150         struct tb_tunnel *tunnel;
 151
 152         tb_switch_discover_tunnels(tb->root_switch, &tcm->tunnel_list, true);
 153
 154         list_for_each_entry(tunnel, &tcm->tunnel_list, list) {
 155                 if (tb_tunnel_is_pci(tunnel)) {
 156                         struct tb_switch *parent = tunnel->dst_port->sw;
 157
 158                         while (parent != tunnel->src_port->sw) {
 159                                 parent->boot = true;
 160                                 parent = tb_switch_parent(parent);
 161                         }
 162                 } else if (tb_tunnel_is_dp(tunnel)) {
 163                         /* Keep the domain from powering down */
 164                         pm_runtime_get_sync(&tunnel->src_port->sw->dev);
 165                         pm_runtime_get_sync(&tunnel->dst_port->sw->dev);
 166                 }
 167         }
 168 }
 169
 170 static int tb_port_configure_xdomain(struct tb_port *port)
 171 {
 172         if (tb_switch_is_usb4(port->sw))
 173                 return usb4_port_configure_xdomain(port);
 174         return tb_lc_configure_xdomain(port);
 175 }
 176
 177 static void tb_port_unconfigure_xdomain(struct tb_port *port)
 178 {
 179         if (tb_switch_is_usb4(port->sw))
 180                 usb4_port_unconfigure_xdomain(port);
 181         else
 182                 tb_lc_unconfigure_xdomain(port);
 183
 184         tb_port_enable(port->dual_link_port);
 185 }
 186
 187 static void tb_scan_xdomain(struct tb_port *port)
 188 {
 189         struct tb_switch *sw = port->sw;
 190         struct tb *tb = sw->tb;
 191         struct tb_xdomain *xd;
 192         u64 route;
 193
 194         if (!tb_is_xdomain_enabled())
 195                 return;
 196
 197         route = tb_downstream_route(port);
 198         xd = tb_xdomain_find_by_route(tb, route);
 199         if (xd) {
 200                 tb_xdomain_put(xd);
 201                 return;
 202         }
 203
 204         xd = tb_xdomain_alloc(tb, &sw->dev, route, tb->root_switch->uuid,
 205                               NULL);
 206         if (xd) {
 207                 tb_port_at(route, sw)->xdomain = xd;
 208                 tb_port_configure_xdomain(port);
 209                 tb_xdomain_add(xd);
 210         }
 211 }
 212
 213 static int tb_enable_tmu(struct tb_switch *sw)
 214 {
 215         int ret;
 216
 217         /* If it is already enabled in correct mode, don't touch it */
 218         if (tb_switch_tmu_hifi_is_enabled(sw, sw->tmu.unidirectional_request))
 219                 return 0;
 220
 221         ret = tb_switch_tmu_disable(sw);
 222         if (ret)
 223                 return ret;
 224
 225         ret = tb_switch_tmu_post_time(sw);
 226         if (ret)
 227                 return ret;
 228
 229         return tb_switch_tmu_enable(sw);
 230 }
 231
 232 /**
 233  * tb_find_unused_port() - return the first inactive port on @sw
 234  * @sw: Switch to find the port on
 235  * @type: Port type to look for
 236  */
 237 static struct tb_port *tb_find_unused_port(struct tb_switch *sw,
 238                                            enum tb_port_type type)
 239 {
 240         struct tb_port *port;
 241
 242         tb_switch_for_each_port(sw, port) {
 243                 if (tb_is_upstream_port(port))
 244                         continue;
 245                 if (port->config.type != type)
 246                         continue;
 247                 if (!port->cap_adap)
 248                         continue;
 249                 if (tb_port_is_enabled(port))
 250                         continue;
 251                 return port;
 252         }
 253         return NULL;
 254 }
 255
 256 static struct tb_port *tb_find_usb3_down(struct tb_switch *sw,
 257                                          const struct tb_port *port)
 258 {
 259         struct tb_port *down;
 260
 261         down = usb4_switch_map_usb3_down(sw, port);
 262         if (down && !tb_usb3_port_is_enabled(down))
 263                 return down;
 264         return NULL;
 265 }
 266
 267 static struct tb_tunnel *tb_find_tunnel(struct tb *tb, enum tb_tunnel_type type,
 268                                         struct tb_port *src_port,
 269                                         struct tb_port *dst_port)
 270 {
 271         struct tb_cm *tcm = tb_priv(tb);
 272         struct tb_tunnel *tunnel;
 273
 274         list_for_each_entry(tunnel, &tcm->tunnel_list, list) {
 275                 if (tunnel->type == type &&
 276                     ((src_port && src_port == tunnel->src_port) ||
 277                      (dst_port && dst_port == tunnel->dst_port))) {
 278                         return tunnel;
 279                 }
 280         }
 281
 282         return NULL;
 283 }
 284
 285 static struct tb_tunnel *tb_find_first_usb3_tunnel(struct tb *tb,
 286                                                    struct tb_port *src_port,
 287                                                    struct tb_port *dst_port)
 288 {
 289         struct tb_port *port, *usb3_down;
 290         struct tb_switch *sw;
 291
 292         /* Pick the router that is deepest in the topology */
 293         if (dst_port->sw->config.depth > src_port->sw->config.depth)
 294                 sw = dst_port->sw;
 295         else
 296                 sw = src_port->sw;
 297
 298         /* Can't be the host router */
 299         if (sw == tb->root_switch)
 300                 return NULL;
 301
 302         /* Find the downstream USB4 port that leads to this router */
 303         port = tb_port_at(tb_route(sw), tb->root_switch);
 304         /* Find the corresponding host router USB3 downstream port */
 305         usb3_down = usb4_switch_map_usb3_down(tb->root_switch, port);
 306         if (!usb3_down)
 307                 return NULL;
 308
 309         return tb_find_tunnel(tb, TB_TUNNEL_USB3, usb3_down, NULL);
 310 }
 311
 312 static int tb_available_bandwidth(struct tb *tb, struct tb_port *src_port,
 313         struct tb_port *dst_port, int *available_up, int *available_down)
 314 {
 315         int usb3_consumed_up, usb3_consumed_down, ret;
 316         struct tb_cm *tcm = tb_priv(tb);
 317         struct tb_tunnel *tunnel;
 318         struct tb_port *port;
 319
 320         tb_port_dbg(dst_port, "calculating available bandwidth\n");
 321
 322         tunnel = tb_find_first_usb3_tunnel(tb, src_port, dst_port);
 323         if (tunnel) {
 324                 ret = tb_tunnel_consumed_bandwidth(tunnel, &usb3_consumed_up,
 325                                                    &usb3_consumed_down);
 326                 if (ret)
 327                         return ret;
 328         } else {
 329                 usb3_consumed_up = 0;
 330                 usb3_consumed_down = 0;
 331         }
 332
 333         *available_up = *available_down = 40000;
 334
 335         /* Find the minimum available bandwidth over all links */
 336         tb_for_each_port_on_path(src_port, dst_port, port) {
 337                 int link_speed, link_width, up_bw, down_bw;
 338
 339                 if (!tb_port_is_null(port))
 340                         continue;
 341
 342                 if (tb_is_upstream_port(port)) {
 343                         link_speed = port->sw->link_speed;
 344                 } else {
 345                         link_speed = tb_port_get_link_speed(port);
 346                         if (link_speed < 0)
 347                                 return link_speed;
 348                 }
 349
 350                 link_width = port->bonded ? 2 : 1;
 351
 352                 up_bw = link_speed * link_width * 1000; /* Mb/s */
 353                 /* Leave 10% guard band */
 354                 up_bw -= up_bw / 10;
 355                 down_bw = up_bw;
 356
 357                 tb_port_dbg(port, "link total bandwidth %d Mb/s\n", up_bw);
 358
 359                 /*
 360                  * Find all DP tunnels that cross the port and reduce
 361                  * their consumed bandwidth from the available.
 362                  */
 363                 list_for_each_entry(tunnel, &tcm->tunnel_list, list) {
 364                         int dp_consumed_up, dp_consumed_down;
 365
 366                         if (!tb_tunnel_is_dp(tunnel))
 367                                 continue;
 368
 369                         if (!tb_tunnel_port_on_path(tunnel, port))
 370                                 continue;
 371
 372                         ret = tb_tunnel_consumed_bandwidth(tunnel,
 373                                                            &dp_consumed_up,
 374                                                            &dp_consumed_down);
 375                         if (ret)
 376                                 return ret;
 377
 378                         up_bw -= dp_consumed_up;
 379                         down_bw -= dp_consumed_down;
 380                 }
 381
 382                 /*
 383                  * If USB3 is tunneled from the host router down to the
 384                  * branch leading to port we need to take USB3 consumed
 385                  * bandwidth into account regardless whether it actually
 386                  * crosses the port.
 387                  */
 388                 up_bw -= usb3_consumed_up;
 389                 down_bw -= usb3_consumed_down;
 390
 391                 if (up_bw < *available_up)
 392                         *available_up = up_bw;
 393                 if (down_bw < *available_down)
 394                         *available_down = down_bw;
 395         }
 396
 397         if (*available_up < 0)
 398                 *available_up = 0;
 399         if (*available_down < 0)
 400                 *available_down = 0;
 401
 402         return 0;
 403 }
 404
 405 static int tb_release_unused_usb3_bandwidth(struct tb *tb,
 406                                             struct tb_port *src_port,
 407                                             struct tb_port *dst_port)
 408 {
 409         struct tb_tunnel *tunnel;
 410
 411         tunnel = tb_find_first_usb3_tunnel(tb, src_port, dst_port);
 412         return tunnel ? tb_tunnel_release_unused_bandwidth(tunnel) : 0;
 413 }
 414
 415 static void tb_reclaim_usb3_bandwidth(struct tb *tb, struct tb_port *src_port,
 416                                       struct tb_port *dst_port)
 417 {
 418         int ret, available_up, available_down;
 419         struct tb_tunnel *tunnel;
 420
 421         tunnel = tb_find_first_usb3_tunnel(tb, src_port, dst_port);
 422         if (!tunnel)
 423                 return;
 424
 425         tb_dbg(tb, "reclaiming unused bandwidth for USB3\n");
 426
 427         /*
 428          * Calculate available bandwidth for the first hop USB3 tunnel.
 429          * That determines the whole USB3 bandwidth for this branch.
 430          */
 431         ret = tb_available_bandwidth(tb, tunnel->src_port, tunnel->dst_port,
 432                                      &available_up, &available_down);
 433         if (ret) {
 434                 tb_warn(tb, "failed to calculate available bandwidth\n");
 435                 return;
 436         }
 437
 438         tb_dbg(tb, "available bandwidth for USB3 %d/%d Mb/s\n",
 439                available_up, available_down);
 440
 441         tb_tunnel_reclaim_available_bandwidth(tunnel, &available_up, &available_down);
 442 }
 443
 444 static int tb_tunnel_usb3(struct tb *tb, struct tb_switch *sw)
 445 {
 446         struct tb_switch *parent = tb_switch_parent(sw);
 447         int ret, available_up, available_down;
 448         struct tb_port *up, *down, *port;
 449         struct tb_cm *tcm = tb_priv(tb);
 450         struct tb_tunnel *tunnel;
 451
 452         if (!tb_acpi_may_tunnel_usb3()) {
 453                 tb_dbg(tb, "USB3 tunneling disabled, not creating tunnel\n");
 454                 return 0;
 455         }
 456
 457         up = tb_switch_find_port(sw, TB_TYPE_USB3_UP);
 458         if (!up)
 459                 return 0;
 460
 461         if (!sw->link_usb4)
 462                 return 0;
 463
 464         /*
 465          * Look up available down port. Since we are chaining it should
 466          * be found right above this switch.
 467          */
 468         port = tb_port_at(tb_route(sw), parent);
 469         down = tb_find_usb3_down(parent, port);
 470         if (!down)
 471                 return 0;
 472
 473         if (tb_route(parent)) {
 474                 struct tb_port *parent_up;
 475                 /*
 476                  * Check first that the parent switch has its upstream USB3
 477                  * port enabled. Otherwise the chain is not complete and
 478                  * there is no point setting up a new tunnel.
 479                  */
 480                 parent_up = tb_switch_find_port(parent, TB_TYPE_USB3_UP);
 481                 if (!parent_up || !tb_port_is_enabled(parent_up))
 482                         return 0;
 483
 484                 /* Make all unused bandwidth available for the new tunnel */
 485                 ret = tb_release_unused_usb3_bandwidth(tb, down, up);
 486                 if (ret)
 487                         return ret;
 488         }
 489
 490         ret = tb_available_bandwidth(tb, down, up, &available_up,
 491                                      &available_down);
 492         if (ret)
 493                 goto err_reclaim;
 494
 495         tb_port_dbg(up, "available bandwidth for new USB3 tunnel %d/%d Mb/s\n",
 496                     available_up, available_down);
 497
 498         tunnel = tb_tunnel_alloc_usb3(tb, up, down, available_up,
 499                                       available_down);
 500         if (!tunnel) {
 501                 ret = -ENOMEM;
 502                 goto err_reclaim;
 503         }
 504
 505         if (tb_tunnel_activate(tunnel)) {
 506                 tb_port_info(up,
 507                              "USB3 tunnel activation failed, aborting\n");
 508                 ret = -EIO;
 509                 goto err_free;
 510         }
 511
 512         list_add_tail(&tunnel->list, &tcm->tunnel_list);
 513         if (tb_route(parent))
 514                 tb_reclaim_usb3_bandwidth(tb, down, up);
 515
 516         return 0;
 517
 518 err_free:
 519         tb_tunnel_free(tunnel);
 520 err_reclaim:
 521         if (tb_route(parent))
 522                 tb_reclaim_usb3_bandwidth(tb, down, up);
 523
 524         return ret;
 525 }
 526
 527 static int tb_create_usb3_tunnels(struct tb_switch *sw)
 528 {
 529         struct tb_port *port;
 530         int ret;
 531
 532         if (!tb_acpi_may_tunnel_usb3())
 533                 return 0;
 534
 535         if (tb_route(sw)) {
 536                 ret = tb_tunnel_usb3(sw->tb, sw);
 537                 if (ret)
 538                         return ret;
 539         }
 540
 541         tb_switch_for_each_port(sw, port) {
 542                 if (!tb_port_has_remote(port))
 543                         continue;
 544                 ret = tb_create_usb3_tunnels(port->remote->sw);
 545                 if (ret)
 546                         return ret;
 547         }
 548
 549         return 0;
 550 }
 551
 552 static void tb_scan_port(struct tb_port *port);
 553
 554 /*
 555  * tb_scan_switch() - scan for and initialize downstream switches
 556  */
 557 static void tb_scan_switch(struct tb_switch *sw)
 558 {
 559         struct tb_port *port;
 560
 561         pm_runtime_get_sync(&sw->dev);
 562
 563         tb_switch_for_each_port(sw, port)
 564                 tb_scan_port(port);
 565
 566         pm_runtime_mark_last_busy(&sw->dev);
 567         pm_runtime_put_autosuspend(&sw->dev);
 568 }
 569
 570 /*
 571  * tb_scan_port() - check for and initialize switches below port
 572  */
 573 static void tb_scan_port(struct tb_port *port)
 574 {
 575         struct tb_cm *tcm = tb_priv(port->sw->tb);
 576         struct tb_port *upstream_port;
 577         struct tb_switch *sw;
 578
 579         if (tb_is_upstream_port(port))
 580                 return;
 581
 582         if (tb_port_is_dpout(port) && tb_dp_port_hpd_is_active(port) == 1 &&
 583             !tb_dp_port_is_enabled(port)) {
 584                 tb_port_dbg(port, "DP adapter HPD set, queuing hotplug\n");
 585                 tb_queue_hotplug(port->sw->tb, tb_route(port->sw), port->port,
 586                                  false);
 587                 return;
 588         }
 589
 590         if (port->config.type != TB_TYPE_PORT)
 591                 return;
 592         if (port->dual_link_port && port->link_nr)
 593                 return; /*
 594                          * Downstream switch is reachable through two ports.
 595                          * Only scan on the primary port (link_nr == 0).
 596                          */
 597         if (tb_wait_for_port(port, false) <= 0)
 598                 return;
 599         if (port->remote) {
 600                 tb_port_dbg(port, "port already has a remote\n");
 601                 return;
 602         }
 603
 604         tb_retimer_scan(port, true);
 605
 606         sw = tb_switch_alloc(port->sw->tb, &port->sw->dev,
 607                              tb_downstream_route(port));
 608         if (IS_ERR(sw)) {
 609                 /*
 610                  * If there is an error accessing the connected switch
 611                  * it may be connected to another domain. Also we allow
 612                  * the other domain to be connected to a max depth switch.
 613                  */
 614                 if (PTR_ERR(sw) == -EIO || PTR_ERR(sw) == -EADDRNOTAVAIL)
 615                         tb_scan_xdomain(port);
 616                 return;
 617         }
 618
 619         if (tb_switch_configure(sw)) {
 620                 tb_switch_put(sw);
 621                 return;
 622         }
 623
 624         /*
 625          * If there was previously another domain connected remove it
 626          * first.
 627          */
 628         if (port->xdomain) {
 629                 tb_xdomain_remove(port->xdomain);
 630                 tb_port_unconfigure_xdomain(port);
 631                 port->xdomain = NULL;
 632         }
 633
 634         /*
 635          * Do not send uevents until we have discovered all existing
 636          * tunnels and know which switches were authorized already by
 637          * the boot firmware.
 638          */
 639         if (!tcm->hotplug_active)
 640                 dev_set_uevent_suppress(&sw->dev, true);
 641
 642         /*
 643          * At the moment Thunderbolt 2 and beyond (devices with LC) we
 644          * can support runtime PM.
 645          */
 646         sw->rpm = sw->generation > 1;
 647
 648         if (tb_switch_add(sw)) {
 649                 tb_switch_put(sw);
 650                 return;
 651         }
 652
 653         /* Link the switches using both links if available */
 654         upstream_port = tb_upstream_port(sw);
 655         port->remote = upstream_port;
 656         upstream_port->remote = port;
 657         if (port->dual_link_port && upstream_port->dual_link_port) {
 658                 port->dual_link_port->remote = upstream_port->dual_link_port;
 659                 upstream_port->dual_link_port->remote = port->dual_link_port;
 660         }
 661
 662         /* Enable lane bonding if supported */
 663         tb_switch_lane_bonding_enable(sw);
 664         /* Set the link configured */
 665         tb_switch_configure_link(sw);
 666         if (tb_switch_enable_clx(sw, TB_CL0S))
 667                 tb_sw_warn(sw, "failed to enable CLx on upstream port\n");
 668
 669         tb_switch_tmu_configure(sw, TB_SWITCH_TMU_RATE_HIFI,
 670                                 tb_switch_is_clx_enabled(sw));
 671
 672         if (tb_enable_tmu(sw))
 673                 tb_sw_warn(sw, "failed to enable TMU\n");
 674
 675         /* Scan upstream retimers */
 676         tb_retimer_scan(upstream_port, true);
 677
 678         /*
 679          * Create USB 3.x tunnels only when the switch is plugged to the
 680          * domain. This is because we scan the domain also during discovery
 681          * and want to discover existing USB 3.x tunnels before we create
 682          * any new.
 683          */
 684         if (tcm->hotplug_active && tb_tunnel_usb3(sw->tb, sw))
 685                 tb_sw_warn(sw, "USB3 tunnel creation failed\n");
 686
 687         tb_add_dp_resources(sw);
 688         tb_scan_switch(sw);
 689 }
 690
 691 static void tb_deactivate_and_free_tunnel(struct tb_tunnel *tunnel)
 692 {
 693         struct tb_port *src_port, *dst_port;
 694         struct tb *tb;
 695
 696         if (!tunnel)
 697                 return;
 698
 699         tb_tunnel_deactivate(tunnel);
 700         list_del(&tunnel->list);
 701
 702         tb = tunnel->tb;
 703         src_port = tunnel->src_port;
 704         dst_port = tunnel->dst_port;
 705
 706         switch (tunnel->type) {
 707         case TB_TUNNEL_DP:
 708                 /*
 709                  * In case of DP tunnel make sure the DP IN resource is
 710                  * deallocated properly.
 711                  */
 712                 tb_switch_dealloc_dp_resource(src_port->sw, src_port);
 713                 /* Now we can allow the domain to runtime suspend again */
 714                 pm_runtime_mark_last_busy(&dst_port->sw->dev);
 715                 pm_runtime_put_autosuspend(&dst_port->sw->dev);
 716                 pm_runtime_mark_last_busy(&src_port->sw->dev);
 717                 pm_runtime_put_autosuspend(&src_port->sw->dev);
 718                 fallthrough;
 719
 720         case TB_TUNNEL_USB3:
 721                 tb_reclaim_usb3_bandwidth(tb, src_port, dst_port);
 722                 break;
 723
 724         default:
 725                 /*
 726                  * PCIe and DMA tunnels do not consume guaranteed
 727                  * bandwidth.
 728                  */
 729                 break;
 730         }
 731
 732         tb_tunnel_free(tunnel);
 733 }
 734
 735 /*
 736  * tb_free_invalid_tunnels() - destroy tunnels of devices that have gone away
 737  */
 738 static void tb_free_invalid_tunnels(struct tb *tb)
 739 {
 740         struct tb_cm *tcm = tb_priv(tb);
 741         struct tb_tunnel *tunnel;
 742         struct tb_tunnel *n;
 743
 744         list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) {
 745                 if (tb_tunnel_is_invalid(tunnel))
 746                         tb_deactivate_and_free_tunnel(tunnel);
 747         }
 748 }
 749
 750 /*
 751  * tb_free_unplugged_children() - traverse hierarchy and free unplugged switches
 752  */
 753 static void tb_free_unplugged_children(struct tb_switch *sw)
 754 {
 755         struct tb_port *port;
 756
 757         tb_switch_for_each_port(sw, port) {
 758                 if (!tb_port_has_remote(port))
 759                         continue;
 760
 761                 if (port->remote->sw->is_unplugged) {
 762                         tb_retimer_remove_all(port);
 763                         tb_remove_dp_resources(port->remote->sw);
 764                         tb_switch_unconfigure_link(port->remote->sw);
 765                         tb_switch_lane_bonding_disable(port->remote->sw);
 766                         tb_switch_remove(port->remote->sw);
 767                         port->remote = NULL;
 768                         if (port->dual_link_port)
 769                                 port->dual_link_port->remote = NULL;
 770                 } else {
 771                         tb_free_unplugged_children(port->remote->sw);
 772                 }
 773         }
 774 }
 775
 776 static struct tb_port *tb_find_pcie_down(struct tb_switch *sw,
 777                                          const struct tb_port *port)
 778 {
 779         struct tb_port *down = NULL;
 780
 781         /*
 782          * To keep plugging devices consistently in the same PCIe
 783          * hierarchy, do mapping here for switch downstream PCIe ports.
 784          */
 785         if (tb_switch_is_usb4(sw)) {
 786                 down = usb4_switch_map_pcie_down(sw, port);
 787         } else if (!tb_route(sw)) {
 788                 int phy_port = tb_phy_port_from_link(port->port);
 789                 int index;
 790
 791                 /*
 792                  * Hard-coded Thunderbolt port to PCIe down port mapping
 793                  * per controller.
 794                  */
 795                 if (tb_switch_is_cactus_ridge(sw) ||
 796                     tb_switch_is_alpine_ridge(sw))
 797                         index = !phy_port ? 6 : 7;
 798                 else if (tb_switch_is_falcon_ridge(sw))
 799                         index = !phy_port ? 6 : 8;
 800                 else if (tb_switch_is_titan_ridge(sw))
 801                         index = !phy_port ? 8 : 9;
 802                 else
 803                         goto out;
 804
 805                 /* Validate the hard-coding */
 806                 if (WARN_ON(index > sw->config.max_port_number))
 807                         goto out;
 808
 809                 down = &sw->ports[index];
 810         }
 811
 812         if (down) {
 813                 if (WARN_ON(!tb_port_is_pcie_down(down)))
 814                         goto out;
 815                 if (tb_pci_port_is_enabled(down))
 816                         goto out;
 817
 818                 return down;
 819         }
 820
 821 out:
 822         return tb_find_unused_port(sw, TB_TYPE_PCIE_DOWN);
 823 }
 824
 825 static struct tb_port *tb_find_dp_out(struct tb *tb, struct tb_port *in)
 826 {
 827         struct tb_port *host_port, *port;
 828         struct tb_cm *tcm = tb_priv(tb);
 829
 830         host_port = tb_route(in->sw) ?
 831                 tb_port_at(tb_route(in->sw), tb->root_switch) : NULL;
 832
 833         list_for_each_entry(port, &tcm->dp_resources, list) {
 834                 if (!tb_port_is_dpout(port))
 835                         continue;
 836
 837                 if (tb_port_is_enabled(port)) {
 838                         tb_port_dbg(port, "in use\n");
 839                         continue;
 840                 }
 841
 842                 tb_port_dbg(port, "DP OUT available\n");
 843
 844                 /*
 845                  * Keep the DP tunnel under the topology starting from
 846                  * the same host router downstream port.
 847                  */
 848                 if (host_port && tb_route(port->sw)) {
 849                         struct tb_port *p;
 850
 851                         p = tb_port_at(tb_route(port->sw), tb->root_switch);
 852                         if (p != host_port)
 853                                 continue;
 854                 }
 855
 856                 return port;
 857         }
 858
 859         return NULL;
 860 }
 861
 862 static void tb_tunnel_dp(struct tb *tb)
 863 {
 864         int available_up, available_down, ret, link_nr;
 865         struct tb_cm *tcm = tb_priv(tb);
 866         struct tb_port *port, *in, *out;
 867         struct tb_tunnel *tunnel;
 868
 869         if (!tb_acpi_may_tunnel_dp()) {
 870                 tb_dbg(tb, "DP tunneling disabled, not creating tunnel\n");
 871                 return;
 872         }
 873
 874         /*
 875          * Find pair of inactive DP IN and DP OUT adapters and then
 876          * establish a DP tunnel between them.
 877          */
 878         tb_dbg(tb, "looking for DP IN <-> DP OUT pairs:\n");
 879
 880         in = NULL;
 881         out = NULL;
 882         list_for_each_entry(port, &tcm->dp_resources, list) {
 883                 if (!tb_port_is_dpin(port))
 884                         continue;
 885
 886                 if (tb_port_is_enabled(port)) {
 887                         tb_port_dbg(port, "in use\n");
 888                         continue;
 889                 }
 890
 891                 tb_port_dbg(port, "DP IN available\n");
 892
 893                 out = tb_find_dp_out(tb, port);
 894                 if (out) {
 895                         in = port;
 896                         break;
 897                 }
 898         }
 899
 900         if (!in) {
 901                 tb_dbg(tb, "no suitable DP IN adapter available, not tunneling\n");
 902                 return;
 903         }
 904         if (!out) {
 905                 tb_dbg(tb, "no suitable DP OUT adapter available, not tunneling\n");
 906                 return;
 907         }
 908
 909         /*
 910          * This is only applicable to links that are not bonded (so
 911          * when Thunderbolt 1 hardware is involved somewhere in the
 912          * topology). For these try to share the DP bandwidth between
 913          * the two lanes.
 914          */
 915         link_nr = 1;
 916         list_for_each_entry(tunnel, &tcm->tunnel_list, list) {
 917                 if (tb_tunnel_is_dp(tunnel)) {
 918                         link_nr = 0;
 919                         break;
 920                 }
 921         }
 922
 923         /*
 924          * DP stream needs the domain to be active so runtime resume
 925          * both ends of the tunnel.
 926          *
 927          * This should bring the routers in the middle active as well
 928          * and keeps the domain from runtime suspending while the DP
 929          * tunnel is active.
 930          */
 931         pm_runtime_get_sync(&in->sw->dev);
 932         pm_runtime_get_sync(&out->sw->dev);
 933
 934         if (tb_switch_alloc_dp_resource(in->sw, in)) {
 935                 tb_port_dbg(in, "no resource available for DP IN, not tunneling\n");
 936                 goto err_rpm_put;
 937         }
 938
 939         /* Make all unused USB3 bandwidth available for the new DP tunnel */
 940         ret = tb_release_unused_usb3_bandwidth(tb, in, out);
 941         if (ret) {
 942                 tb_warn(tb, "failed to release unused bandwidth\n");
 943                 goto err_dealloc_dp;
 944         }
 945
 946         ret = tb_available_bandwidth(tb, in, out, &available_up,
 947                                      &available_down);
 948         if (ret)
 949                 goto err_reclaim;
 950
 951         tb_dbg(tb, "available bandwidth for new DP tunnel %u/%u Mb/s\n",
 952                available_up, available_down);
 953
 954         tunnel = tb_tunnel_alloc_dp(tb, in, out, link_nr, available_up,
 955                                     available_down);
 956         if (!tunnel) {
 957                 tb_port_dbg(out, "could not allocate DP tunnel\n");
 958                 goto err_reclaim;
 959         }
 960
 961         if (tb_tunnel_activate(tunnel)) {
 962                 tb_port_info(out, "DP tunnel activation failed, aborting\n");
 963                 goto err_free;
 964         }
 965
 966         list_add_tail(&tunnel->list, &tcm->tunnel_list);
 967         tb_reclaim_usb3_bandwidth(tb, in, out);
 968         return;
 969
 970 err_free:
 971         tb_tunnel_free(tunnel);
 972 err_reclaim:
 973         tb_reclaim_usb3_bandwidth(tb, in, out);
 974 err_dealloc_dp:
 975         tb_switch_dealloc_dp_resource(in->sw, in);
 976 err_rpm_put:
 977         pm_runtime_mark_last_busy(&out->sw->dev);
 978         pm_runtime_put_autosuspend(&out->sw->dev);
 979         pm_runtime_mark_last_busy(&in->sw->dev);
 980         pm_runtime_put_autosuspend(&in->sw->dev);
 981 }
 982
 983 static void tb_dp_resource_unavailable(struct tb *tb, struct tb_port *port)
 984 {
 985         struct tb_port *in, *out;
 986         struct tb_tunnel *tunnel;
 987
 988         if (tb_port_is_dpin(port)) {
 989                 tb_port_dbg(port, "DP IN resource unavailable\n");
 990                 in = port;
 991                 out = NULL;
 992         } else {
 993                 tb_port_dbg(port, "DP OUT resource unavailable\n");
 994                 in = NULL;
 995                 out = port;
 996         }
 997
 998         tunnel = tb_find_tunnel(tb, TB_TUNNEL_DP, in, out);
 999         tb_deactivate_and_free_tunnel(tunnel);
1000         list_del_init(&port->list);
1001
1002         /*
1003          * See if there is another DP OUT port that can be used for
1004          * to create another tunnel.
1005          */
1006         tb_tunnel_dp(tb);
1007 }
1008
1009 static void tb_dp_resource_available(struct tb *tb, struct tb_port *port)
1010 {
1011         struct tb_cm *tcm = tb_priv(tb);
1012         struct tb_port *p;
1013
1014         if (tb_port_is_enabled(port))
1015                 return;
1016
1017         list_for_each_entry(p, &tcm->dp_resources, list) {
1018                 if (p == port)
1019                         return;
1020         }
1021
1022         tb_port_dbg(port, "DP %s resource available\n",
1023                     tb_port_is_dpin(port) ? "IN" : "OUT");
1024         list_add_tail(&port->list, &tcm->dp_resources);
1025
1026         /* Look for suitable DP IN <-> DP OUT pairs now */
1027         tb_tunnel_dp(tb);
1028 }
1029
1030 static void tb_disconnect_and_release_dp(struct tb *tb)
1031 {
1032         struct tb_cm *tcm = tb_priv(tb);
1033         struct tb_tunnel *tunnel, *n;
1034
1035         /*
1036          * Tear down all DP tunnels and release their resources. They
1037          * will be re-established after resume based on plug events.
1038          */
1039         list_for_each_entry_safe_reverse(tunnel, n, &tcm->tunnel_list, list) {
1040                 if (tb_tunnel_is_dp(tunnel))
1041                         tb_deactivate_and_free_tunnel(tunnel);
1042         }
1043
1044         while (!list_empty(&tcm->dp_resources)) {
1045                 struct tb_port *port;
1046
1047                 port = list_first_entry(&tcm->dp_resources,
1048                                         struct tb_port, list);
1049                 list_del_init(&port->list);
1050         }
1051 }
1052
1053 static int tb_disconnect_pci(struct tb *tb, struct tb_switch *sw)
1054 {
1055         struct tb_tunnel *tunnel;
1056         struct tb_port *up;
1057
1058         up = tb_switch_find_port(sw, TB_TYPE_PCIE_UP);
1059         if (WARN_ON(!up))
1060                 return -ENODEV;
1061
1062         tunnel = tb_find_tunnel(tb, TB_TUNNEL_PCI, NULL, up);
1063         if (WARN_ON(!tunnel))
1064                 return -ENODEV;
1065
1066         tb_switch_xhci_disconnect(sw);
1067
1068         tb_tunnel_deactivate(tunnel);
1069         list_del(&tunnel->list);
1070         tb_tunnel_free(tunnel);
1071         return 0;
1072 }
1073
1074 static int tb_tunnel_pci(struct tb *tb, struct tb_switch *sw)
1075 {
1076         struct tb_port *up, *down, *port;
1077         struct tb_cm *tcm = tb_priv(tb);
1078         struct tb_switch *parent_sw;
1079         struct tb_tunnel *tunnel;
1080
1081         up = tb_switch_find_port(sw, TB_TYPE_PCIE_UP);
1082         if (!up)
1083                 return 0;
1084
1085         /*
1086          * Look up available down port. Since we are chaining it should
1087          * be found right above this switch.
1088          */
1089         parent_sw = tb_to_switch(sw->dev.parent);
1090         port = tb_port_at(tb_route(sw), parent_sw);
1091         down = tb_find_pcie_down(parent_sw, port);
1092         if (!down)
1093                 return 0;
1094
1095         tunnel = tb_tunnel_alloc_pci(tb, up, down);
1096         if (!tunnel)
1097                 return -ENOMEM;
1098
1099         if (tb_tunnel_activate(tunnel)) {
1100                 tb_port_info(up,
1101                              "PCIe tunnel activation failed, aborting\n");
1102                 tb_tunnel_free(tunnel);
1103                 return -EIO;
1104         }
1105
1106         /*
1107          * PCIe L1 is needed to enable CL0s for Titan Ridge so enable it
1108          * here.
1109          */
1110         if (tb_switch_pcie_l1_enable(sw))
1111                 tb_sw_warn(sw, "failed to enable PCIe L1 for Titan Ridge\n");
1112
1113         if (tb_switch_xhci_connect(sw))
1114                 tb_sw_warn(sw, "failed to connect xHCI\n");
1115
1116         list_add_tail(&tunnel->list, &tcm->tunnel_list);
1117         return 0;
1118 }
1119
1120 static int tb_approve_xdomain_paths(struct tb *tb, struct tb_xdomain *xd,
1121                                     int transmit_path, int transmit_ring,
1122                                     int receive_path, int receive_ring)
1123 {
1124         struct tb_cm *tcm = tb_priv(tb);
1125         struct tb_port *nhi_port, *dst_port;
1126         struct tb_tunnel *tunnel;
1127         struct tb_switch *sw;
1128
1129         sw = tb_to_switch(xd->dev.parent);
1130         dst_port = tb_port_at(xd->route, sw);
1131         nhi_port = tb_switch_find_port(tb->root_switch, TB_TYPE_NHI);
1132
1133         mutex_lock(&tb->lock);
1134         tunnel = tb_tunnel_alloc_dma(tb, nhi_port, dst_port, transmit_path,
1135                                      transmit_ring, receive_path, receive_ring);
1136         if (!tunnel) {
1137                 mutex_unlock(&tb->lock);
1138                 return -ENOMEM;
1139         }
1140
1141         if (tb_tunnel_activate(tunnel)) {
1142                 tb_port_info(nhi_port,
1143                              "DMA tunnel activation failed, aborting\n");
1144                 tb_tunnel_free(tunnel);
1145                 mutex_unlock(&tb->lock);
1146                 return -EIO;
1147         }
1148
1149         list_add_tail(&tunnel->list, &tcm->tunnel_list);
1150         mutex_unlock(&tb->lock);
1151         return 0;
1152 }
1153
1154 static void __tb_disconnect_xdomain_paths(struct tb *tb, struct tb_xdomain *xd,
1155                                           int transmit_path, int transmit_ring,
1156                                           int receive_path, int receive_ring)
1157 {
1158         struct tb_cm *tcm = tb_priv(tb);
1159         struct tb_port *nhi_port, *dst_port;
1160         struct tb_tunnel *tunnel, *n;
1161         struct tb_switch *sw;
1162
1163         sw = tb_to_switch(xd->dev.parent);
1164         dst_port = tb_port_at(xd->route, sw);
1165         nhi_port = tb_switch_find_port(tb->root_switch, TB_TYPE_NHI);
1166
1167         list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) {
1168                 if (!tb_tunnel_is_dma(tunnel))
1169                         continue;
1170                 if (tunnel->src_port != nhi_port || tunnel->dst_port != dst_port)
1171                         continue;
1172
1173                 if (tb_tunnel_match_dma(tunnel, transmit_path, transmit_ring,
1174                                         receive_path, receive_ring))
1175                         tb_deactivate_and_free_tunnel(tunnel);
1176         }
1177 }
1178
1179 static int tb_disconnect_xdomain_paths(struct tb *tb, struct tb_xdomain *xd,
1180                                        int transmit_path, int transmit_ring,
1181                                        int receive_path, int receive_ring)
1182 {
1183         if (!xd->is_unplugged) {
1184                 mutex_lock(&tb->lock);
1185                 __tb_disconnect_xdomain_paths(tb, xd, transmit_path,
1186                                               transmit_ring, receive_path,
1187                                               receive_ring);
1188                 mutex_unlock(&tb->lock);
1189         }
1190         return 0;
1191 }
1192
1193 /* hotplug handling */
1194
1195 /*
1196  * tb_handle_hotplug() - handle hotplug event
1197  *
1198  * Executes on tb->wq.
1199  */
1200 static void tb_handle_hotplug(struct work_struct *work)
1201 {
1202         struct tb_hotplug_event *ev = container_of(work, typeof(*ev), work);
1203         struct tb *tb = ev->tb;
1204         struct tb_cm *tcm = tb_priv(tb);
1205         struct tb_switch *sw;
1206         struct tb_port *port;
1207
1208         /* Bring the domain back from sleep if it was suspended */
1209         pm_runtime_get_sync(&tb->dev);
1210
1211         mutex_lock(&tb->lock);
1212         if (!tcm->hotplug_active)
1213                 goto out; /* during init, suspend or shutdown */
1214
1215         sw = tb_switch_find_by_route(tb, ev->route);
1216         if (!sw) {
1217                 tb_warn(tb,
1218                         "hotplug event from non existent switch %llx:%x (unplug: %d)\n",
1219                         ev->route, ev->port, ev->unplug);
1220                 goto out;
1221         }
1222         if (ev->port > sw->config.max_port_number) {
1223                 tb_warn(tb,
1224                         "hotplug event from non existent port %llx:%x (unplug: %d)\n",
1225                         ev->route, ev->port, ev->unplug);
1226                 goto put_sw;
1227         }
1228         port = &sw->ports[ev->port];
1229         if (tb_is_upstream_port(port)) {
1230                 tb_dbg(tb, "hotplug event for upstream port %llx:%x (unplug: %d)\n",
1231                        ev->route, ev->port, ev->unplug);
1232                 goto put_sw;
1233         }
1234
1235         pm_runtime_get_sync(&sw->dev);
1236
1237         if (ev->unplug) {
1238                 tb_retimer_remove_all(port);
1239
1240                 if (tb_port_has_remote(port)) {
1241                         tb_port_dbg(port, "switch unplugged\n");
1242                         tb_sw_set_unplugged(port->remote->sw);
1243                         tb_free_invalid_tunnels(tb);
1244                         tb_remove_dp_resources(port->remote->sw);
1245                         tb_switch_tmu_disable(port->remote->sw);
1246                         tb_switch_unconfigure_link(port->remote->sw);
1247                         tb_switch_lane_bonding_disable(port->remote->sw);
1248                         tb_switch_remove(port->remote->sw);
1249                         port->remote = NULL;
1250                         if (port->dual_link_port)
1251                                 port->dual_link_port->remote = NULL;
1252                         /* Maybe we can create another DP tunnel */
1253                         tb_tunnel_dp(tb);
1254                 } else if (port->xdomain) {
1255                         struct tb_xdomain *xd = tb_xdomain_get(port->xdomain);
1256
1257                         tb_port_dbg(port, "xdomain unplugged\n");
1258                         /*
1259                          * Service drivers are unbound during
1260                          * tb_xdomain_remove() so setting XDomain as
1261                          * unplugged here prevents deadlock if they call
1262                          * tb_xdomain_disable_paths(). We will tear down
1263                          * all the tunnels below.
1264                          */
1265                         xd->is_unplugged = true;
1266                         tb_xdomain_remove(xd);
1267                         port->xdomain = NULL;
1268                         __tb_disconnect_xdomain_paths(tb, xd, -1, -1, -1, -1);
1269                         tb_xdomain_put(xd);
1270                         tb_port_unconfigure_xdomain(port);
1271                 } else if (tb_port_is_dpout(port) || tb_port_is_dpin(port)) {
1272                         tb_dp_resource_unavailable(tb, port);
1273                 } else if (!port->port) {
1274                         tb_sw_dbg(sw, "xHCI disconnect request\n");
1275                         tb_switch_xhci_disconnect(sw);
1276                 } else {
1277                         tb_port_dbg(port,
1278                                    "got unplug event for disconnected port, ignoring\n");
1279                 }
1280         } else if (port->remote) {
1281                 tb_port_dbg(port, "got plug event for connected port, ignoring\n");
1282         } else if (!port->port && sw->authorized) {
1283                 tb_sw_dbg(sw, "xHCI connect request\n");
1284                 tb_switch_xhci_connect(sw);
1285         } else {
1286                 if (tb_port_is_null(port)) {
1287                         tb_port_dbg(port, "hotplug: scanning\n");
1288                         tb_scan_port(port);
1289                         if (!port->remote)
1290                                 tb_port_dbg(port, "hotplug: no switch found\n");
1291                 } else if (tb_port_is_dpout(port) || tb_port_is_dpin(port)) {
1292                         tb_dp_resource_available(tb, port);
1293                 }
1294         }
1295
1296         pm_runtime_mark_last_busy(&sw->dev);
1297         pm_runtime_put_autosuspend(&sw->dev);
1298
1299 put_sw:
1300         tb_switch_put(sw);
1301 out:
1302         mutex_unlock(&tb->lock);
1303
1304         pm_runtime_mark_last_busy(&tb->dev);
1305         pm_runtime_put_autosuspend(&tb->dev);
1306
1307         kfree(ev);
1308 }
1309
1310 /*
1311  * tb_schedule_hotplug_handler() - callback function for the control channel
1312  *
1313  * Delegates to tb_handle_hotplug.
1314  */
1315 static void tb_handle_event(struct tb *tb, enum tb_cfg_pkg_type type,
1316                             const void *buf, size_t size)
1317 {
1318         const struct cfg_event_pkg *pkg = buf;
1319         u64 route;
1320
1321         if (type != TB_CFG_PKG_EVENT) {
1322                 tb_warn(tb, "unexpected event %#x, ignoring\n", type);
1323                 return;
1324         }
1325
1326         route = tb_cfg_get_route(&pkg->header);
1327
1328         if (tb_cfg_ack_plug(tb->ctl, route, pkg->port, pkg->unplug)) {
1329                 tb_warn(tb, "could not ack plug event on %llx:%x\n", route,
1330                         pkg->port);
1331         }
1332
1333         tb_queue_hotplug(tb, route, pkg->port, pkg->unplug);
1334 }
1335
1336 static void tb_stop(struct tb *tb)
1337 {
1338         struct tb_cm *tcm = tb_priv(tb);
1339         struct tb_tunnel *tunnel;
1340         struct tb_tunnel *n;
1341
1342         cancel_delayed_work(&tcm->remove_work);
1343         /* tunnels are only present after everything has been initialized */
1344         list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) {
1345                 /*
1346                  * DMA tunnels require the driver to be functional so we
1347                  * tear them down. Other protocol tunnels can be left
1348                  * intact.
1349                  */
1350                 if (tb_tunnel_is_dma(tunnel))
1351                         tb_tunnel_deactivate(tunnel);
1352                 tb_tunnel_free(tunnel);
1353         }
1354         tb_switch_remove(tb->root_switch);
1355         tcm->hotplug_active = false; /* signal tb_handle_hotplug to quit */
1356 }
1357
1358 static int tb_scan_finalize_switch(struct device *dev, void *data)
1359 {
1360         if (tb_is_switch(dev)) {
1361                 struct tb_switch *sw = tb_to_switch(dev);
1362
1363                 /*
1364                  * If we found that the switch was already setup by the
1365                  * boot firmware, mark it as authorized now before we
1366                  * send uevent to userspace.
1367                  */
1368                 if (sw->boot)
1369                         sw->authorized = 1;
1370
1371                 dev_set_uevent_suppress(dev, false);
1372                 kobject_uevent(&dev->kobj, KOBJ_ADD);
1373                 device_for_each_child(dev, NULL, tb_scan_finalize_switch);
1374         }
1375
1376         return 0;
1377 }
1378
1379 static int tb_start(struct tb *tb)
1380 {
1381         struct tb_cm *tcm = tb_priv(tb);
1382         int ret;
1383
1384         tb->root_switch = tb_switch_alloc(tb, &tb->dev, 0);
1385         if (IS_ERR(tb->root_switch))
1386                 return PTR_ERR(tb->root_switch);
1387
1388         /*
1389          * ICM firmware upgrade needs running firmware and in native
1390          * mode that is not available so disable firmware upgrade of the
1391          * root switch.
1392          */
1393         tb->root_switch->no_nvm_upgrade = true;
1394         /* All USB4 routers support runtime PM */
1395         tb->root_switch->rpm = tb_switch_is_usb4(tb->root_switch);
1396
1397         ret = tb_switch_configure(tb->root_switch);
1398         if (ret) {
1399                 tb_switch_put(tb->root_switch);
1400                 return ret;
1401         }
1402
1403         /* Announce the switch to the world */
1404         ret = tb_switch_add(tb->root_switch);
1405         if (ret) {
1406                 tb_switch_put(tb->root_switch);
1407                 return ret;
1408         }
1409
1410         tb_switch_tmu_configure(tb->root_switch, TB_SWITCH_TMU_RATE_HIFI, false);
1411         /* Enable TMU if it is off */
1412         tb_switch_tmu_enable(tb->root_switch);
1413         /* Full scan to discover devices added before the driver was loaded. */
1414         tb_scan_switch(tb->root_switch);
1415         /* Find out tunnels created by the boot firmware */
1416         tb_discover_tunnels(tb);
1417         /*
1418          * If the boot firmware did not create USB 3.x tunnels create them
1419          * now for the whole topology.
1420          */
1421         tb_create_usb3_tunnels(tb->root_switch);
1422         /* Add DP IN resources for the root switch */
1423         tb_add_dp_resources(tb->root_switch);
1424         /* Make the discovered switches available to the userspace */
1425         device_for_each_child(&tb->root_switch->dev, NULL,
1426                               tb_scan_finalize_switch);
1427
1428         /* Allow tb_handle_hotplug to progress events */
1429         tcm->hotplug_active = true;
1430         return 0;
1431 }
1432
1433 static int tb_suspend_noirq(struct tb *tb)
1434 {
1435         struct tb_cm *tcm = tb_priv(tb);
1436
1437         tb_dbg(tb, "suspending...\n");
1438         tb_disconnect_and_release_dp(tb);
1439         tb_switch_suspend(tb->root_switch, false);
1440         tcm->hotplug_active = false; /* signal tb_handle_hotplug to quit */
1441         tb_dbg(tb, "suspend finished\n");
1442
1443         return 0;
1444 }
1445
1446 static void tb_restore_children(struct tb_switch *sw)
1447 {
1448         struct tb_port *port;
1449
1450         /* No need to restore if the router is already unplugged */
1451         if (sw->is_unplugged)
1452                 return;
1453
1454         if (tb_switch_enable_clx(sw, TB_CL0S))
1455                 tb_sw_warn(sw, "failed to re-enable CLx on upstream port\n");
1456
1457         /*
1458          * tb_switch_tmu_configure() was already called when the switch was
1459          * added before entering system sleep or runtime suspend,
1460          * so no need to call it again before enabling TMU.
1461          */
1462         if (tb_enable_tmu(sw))
1463                 tb_sw_warn(sw, "failed to restore TMU configuration\n");
1464
1465         tb_switch_for_each_port(sw, port) {
1466                 if (!tb_port_has_remote(port) && !port->xdomain)
1467                         continue;
1468
1469                 if (port->remote) {
1470                         tb_switch_lane_bonding_enable(port->remote->sw);
1471                         tb_switch_configure_link(port->remote->sw);
1472
1473                         tb_restore_children(port->remote->sw);
1474                 } else if (port->xdomain) {
1475                         tb_port_configure_xdomain(port);
1476                 }
1477         }
1478 }
1479
1480 static int tb_resume_noirq(struct tb *tb)
1481 {
1482         struct tb_cm *tcm = tb_priv(tb);
1483         struct tb_tunnel *tunnel, *n;
1484         unsigned int usb3_delay = 0;
1485         LIST_HEAD(tunnels);
1486
1487         tb_dbg(tb, "resuming...\n");
1488
1489         /* remove any pci devices the firmware might have setup */
1490         tb_switch_reset(tb->root_switch);
1491
1492         tb_switch_resume(tb->root_switch);
1493         tb_free_invalid_tunnels(tb);
1494         tb_free_unplugged_children(tb->root_switch);
1495         tb_restore_children(tb->root_switch);
1496
1497         /*
1498          * If we get here from suspend to disk the boot firmware or the
1499          * restore kernel might have created tunnels of its own. Since
1500          * we cannot be sure they are usable for us we find and tear
1501          * them down.
1502          */
1503         tb_switch_discover_tunnels(tb->root_switch, &tunnels, false);
1504         list_for_each_entry_safe_reverse(tunnel, n, &tunnels, list) {
1505                 if (tb_tunnel_is_usb3(tunnel))
1506                         usb3_delay = 500;
1507                 tb_tunnel_deactivate(tunnel);
1508                 tb_tunnel_free(tunnel);
1509         }
1510
1511         /* Re-create our tunnels now */
1512         list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) {
1513                 /* USB3 requires delay before it can be re-activated */
1514                 if (tb_tunnel_is_usb3(tunnel)) {
1515                         msleep(usb3_delay);
1516                         /* Only need to do it once */
1517                         usb3_delay = 0;
1518                 }
1519                 tb_tunnel_restart(tunnel);
1520         }
1521         if (!list_empty(&tcm->tunnel_list)) {
1522                 /*
1523                  * the pcie links need some time to get going.
1524                  * 100ms works for me...
1525                  */
1526                 tb_dbg(tb, "tunnels restarted, sleeping for 100ms\n");
1527                 msleep(100);
1528         }
1529          /* Allow tb_handle_hotplug to progress events */
1530         tcm->hotplug_active = true;
1531         tb_dbg(tb, "resume finished\n");
1532
1533         return 0;
1534 }
1535
1536 static int tb_free_unplugged_xdomains(struct tb_switch *sw)
1537 {
1538         struct tb_port *port;
1539         int ret = 0;
1540
1541         tb_switch_for_each_port(sw, port) {
1542                 if (tb_is_upstream_port(port))
1543                         continue;
1544                 if (port->xdomain && port->xdomain->is_unplugged) {
1545                         tb_retimer_remove_all(port);
1546                         tb_xdomain_remove(port->xdomain);
1547                         tb_port_unconfigure_xdomain(port);
1548                         port->xdomain = NULL;
1549                         ret++;
1550                 } else if (port->remote) {
1551                         ret += tb_free_unplugged_xdomains(port->remote->sw);
1552                 }
1553         }
1554
1555         return ret;
1556 }
1557
1558 static int tb_freeze_noirq(struct tb *tb)
1559 {
1560         struct tb_cm *tcm = tb_priv(tb);
1561
1562         tcm->hotplug_active = false;
1563         return 0;
1564 }
1565
1566 static int tb_thaw_noirq(struct tb *tb)
1567 {
1568         struct tb_cm *tcm = tb_priv(tb);
1569
1570         tcm->hotplug_active = true;
1571         return 0;
1572 }
1573
1574 static void tb_complete(struct tb *tb)
1575 {
1576         /*
1577          * Release any unplugged XDomains and if there is a case where
1578          * another domain is swapped in place of unplugged XDomain we
1579          * need to run another rescan.
1580          */
1581         mutex_lock(&tb->lock);
1582         if (tb_free_unplugged_xdomains(tb->root_switch))
1583                 tb_scan_switch(tb->root_switch);
1584         mutex_unlock(&tb->lock);
1585 }
1586
1587 static int tb_runtime_suspend(struct tb *tb)
1588 {
1589         struct tb_cm *tcm = tb_priv(tb);
1590
1591         mutex_lock(&tb->lock);
1592         tb_switch_suspend(tb->root_switch, true);
1593         tcm->hotplug_active = false;
1594         mutex_unlock(&tb->lock);
1595
1596         return 0;
1597 }
1598
1599 static void tb_remove_work(struct work_struct *work)
1600 {
1601         struct tb_cm *tcm = container_of(work, struct tb_cm, remove_work.work);
1602         struct tb *tb = tcm_to_tb(tcm);
1603
1604         mutex_lock(&tb->lock);
1605         if (tb->root_switch) {
1606                 tb_free_unplugged_children(tb->root_switch);
1607                 tb_free_unplugged_xdomains(tb->root_switch);
1608         }
1609         mutex_unlock(&tb->lock);
1610 }
1611
1612 static int tb_runtime_resume(struct tb *tb)
1613 {
1614         struct tb_cm *tcm = tb_priv(tb);
1615         struct tb_tunnel *tunnel, *n;
1616
1617         mutex_lock(&tb->lock);
1618         tb_switch_resume(tb->root_switch);
1619         tb_free_invalid_tunnels(tb);
1620         tb_restore_children(tb->root_switch);
1621         list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list)
1622                 tb_tunnel_restart(tunnel);
1623         tcm->hotplug_active = true;
1624         mutex_unlock(&tb->lock);
1625
1626         /*
1627          * Schedule cleanup of any unplugged devices. Run this in a
1628          * separate thread to avoid possible deadlock if the device
1629          * removal runtime resumes the unplugged device.
1630          */
1631         queue_delayed_work(tb->wq, &tcm->remove_work, msecs_to_jiffies(50));
1632         return 0;
1633 }
1634
1635 static const struct tb_cm_ops tb_cm_ops = {
1636         .start = tb_start,
1637         .stop = tb_stop,
1638         .suspend_noirq = tb_suspend_noirq,
1639         .resume_noirq = tb_resume_noirq,
1640         .freeze_noirq = tb_freeze_noirq,
1641         .thaw_noirq = tb_thaw_noirq,
1642         .complete = tb_complete,
1643         .runtime_suspend = tb_runtime_suspend,
1644         .runtime_resume = tb_runtime_resume,
1645         .handle_event = tb_handle_event,
1646         .disapprove_switch = tb_disconnect_pci,
1647         .approve_switch = tb_tunnel_pci,
1648         .approve_xdomain_paths = tb_approve_xdomain_paths,
1649         .disconnect_xdomain_paths = tb_disconnect_xdomain_paths,
1650 };
1651
1652 /*
1653  * During suspend the Thunderbolt controller is reset and all PCIe
1654  * tunnels are lost. The NHI driver will try to reestablish all tunnels
1655  * during resume. This adds device links between the tunneled PCIe
1656  * downstream ports and the NHI so that the device core will make sure
1657  * NHI is resumed first before the rest.
1658  */
1659 static void tb_apple_add_links(struct tb_nhi *nhi)
1660 {
1661         struct pci_dev *upstream, *pdev;
1662
1663         if (!x86_apple_machine)
1664                 return;
1665
1666         switch (nhi->pdev->device) {
1667         case PCI_DEVICE_ID_INTEL_LIGHT_RIDGE:
1668         case PCI_DEVICE_ID_INTEL_CACTUS_RIDGE_4C:
1669         case PCI_DEVICE_ID_INTEL_FALCON_RIDGE_2C_NHI:
1670         case PCI_DEVICE_ID_INTEL_FALCON_RIDGE_4C_NHI:
1671                 break;
1672         default:
1673                 return;
1674         }
1675
1676         upstream = pci_upstream_bridge(nhi->pdev);
1677         while (upstream) {
1678                 if (!pci_is_pcie(upstream))
1679                         return;
1680                 if (pci_pcie_type(upstream) == PCI_EXP_TYPE_UPSTREAM)
1681                         break;
1682                 upstream = pci_upstream_bridge(upstream);
1683         }
1684
1685         if (!upstream)
1686                 return;
1687
1688         /*
1689          * For each hotplug downstream port, create add device link
1690          * back to NHI so that PCIe tunnels can be re-established after
1691          * sleep.
1692          */
1693         for_each_pci_bridge(pdev, upstream->subordinate) {
1694                 const struct device_link *link;
1695
1696                 if (!pci_is_pcie(pdev))
1697                         continue;
1698                 if (pci_pcie_type(pdev) != PCI_EXP_TYPE_DOWNSTREAM ||
1699                     !pdev->is_hotplug_bridge)
1700                         continue;
1701
1702                 link = device_link_add(&pdev->dev, &nhi->pdev->dev,
1703                                        DL_FLAG_AUTOREMOVE_SUPPLIER |
1704                                        DL_FLAG_PM_RUNTIME);
1705                 if (link) {
1706                         dev_dbg(&nhi->pdev->dev, "created link from %s\n",
1707                                 dev_name(&pdev->dev));
1708                 } else {
1709                         dev_warn(&nhi->pdev->dev, "device link creation from %s failed\n",
1710                                  dev_name(&pdev->dev));
1711                 }
1712         }
1713 }
1714
1715 struct tb *tb_probe(struct tb_nhi *nhi)
1716 {
1717         struct tb_cm *tcm;
1718         struct tb *tb;
1719
1720         tb = tb_domain_alloc(nhi, TB_TIMEOUT, sizeof(*tcm));
1721         if (!tb)
1722                 return NULL;
1723
1724         if (tb_acpi_may_tunnel_pcie())
1725                 tb->security_level = TB_SECURITY_USER;
1726         else
1727                 tb->security_level = TB_SECURITY_NOPCIE;
1728
1729         tb->cm_ops = &tb_cm_ops;
1730
1731         tcm = tb_priv(tb);
1732         INIT_LIST_HEAD(&tcm->tunnel_list);
1733         INIT_LIST_HEAD(&tcm->dp_resources);
1734         INIT_DELAYED_WORK(&tcm->remove_work, tb_remove_work);
1735
1736         tb_dbg(tb, "using software connection manager\n");
1737
1738         tb_apple_add_links(nhi);
1739         tb_acpi_add_links(nhi);
1740
1741         return tb;
1742 }