drivers/thunderbolt/tb.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Thunderbolt driver - bus logic (NHI independent)
   4  *
   5  * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com>
   6  * Copyright (C) 2019, Intel Corporation
   7  */
   8
   9 #include <linux/slab.h>
  10 #include <linux/errno.h>
  11 #include <linux/delay.h>
  12 #include <linux/pm_runtime.h>
  13 #include <linux/platform_data/x86/apple.h>
  14
  15 #include "tb.h"
  16 #include "tb_regs.h"
  17 #include "tunnel.h"
  18
  19 #define TB_TIMEOUT      100 /* ms */
  20
  21 /**
  22  * struct tb_cm - Simple Thunderbolt connection manager
  23  * @tunnel_list: List of active tunnels
  24  * @dp_resources: List of available DP resources for DP tunneling
  25  * @hotplug_active: tb_handle_hotplug will stop progressing plug
  26  *                  events and exit if this is not set (it needs to
  27  *                  acquire the lock one more time). Used to drain wq
  28  *                  after cfg has been paused.
  29  * @remove_work: Work used to remove any unplugged routers after
  30  *               runtime resume
  31  */
  32 struct tb_cm {
  33         struct list_head tunnel_list;
  34         struct list_head dp_resources;
  35         bool hotplug_active;
  36         struct delayed_work remove_work;
  37 };
  38
  39 static inline struct tb *tcm_to_tb(struct tb_cm *tcm)
  40 {
  41         return ((void *)tcm - sizeof(struct tb));
  42 }
  43
  44 struct tb_hotplug_event {
  45         struct work_struct work;
  46         struct tb *tb;
  47         u64 route;
  48         u8 port;
  49         bool unplug;
  50 };
  51
  52 static void tb_handle_hotplug(struct work_struct *work);
  53
  54 static void tb_queue_hotplug(struct tb *tb, u64 route, u8 port, bool unplug)
  55 {
  56         struct tb_hotplug_event *ev;
  57
  58         ev = kmalloc(sizeof(*ev), GFP_KERNEL);
  59         if (!ev)
  60                 return;
  61
  62         ev->tb = tb;
  63         ev->route = route;
  64         ev->port = port;
  65         ev->unplug = unplug;
  66         INIT_WORK(&ev->work, tb_handle_hotplug);
  67         queue_work(tb->wq, &ev->work);
  68 }
  69
  70 /* enumeration & hot plug handling */
  71
  72 static void tb_add_dp_resources(struct tb_switch *sw)
  73 {
  74         struct tb_cm *tcm = tb_priv(sw->tb);
  75         struct tb_port *port;
  76
  77         tb_switch_for_each_port(sw, port) {
  78                 if (!tb_port_is_dpin(port))
  79                         continue;
  80
  81                 if (!tb_switch_query_dp_resource(sw, port))
  82                         continue;
  83
  84                 list_add_tail(&port->list, &tcm->dp_resources);
  85                 tb_port_dbg(port, "DP IN resource available\n");
  86         }
  87 }
  88
  89 static void tb_remove_dp_resources(struct tb_switch *sw)
  90 {
  91         struct tb_cm *tcm = tb_priv(sw->tb);
  92         struct tb_port *port, *tmp;
  93
  94         /* Clear children resources first */
  95         tb_switch_for_each_port(sw, port) {
  96                 if (tb_port_has_remote(port))
  97                         tb_remove_dp_resources(port->remote->sw);
  98         }
  99
 100         list_for_each_entry_safe(port, tmp, &tcm->dp_resources, list) {
 101                 if (port->sw == sw) {
 102                         tb_port_dbg(port, "DP OUT resource unavailable\n");
 103                         list_del_init(&port->list);
 104                 }
 105         }
 106 }
 107
 108 static void tb_discover_dp_resource(struct tb *tb, struct tb_port *port)
 109 {
 110         struct tb_cm *tcm = tb_priv(tb);
 111         struct tb_port *p;
 112
 113         list_for_each_entry(p, &tcm->dp_resources, list) {
 114                 if (p == port)
 115                         return;
 116         }
 117
 118         tb_port_dbg(port, "DP %s resource available discovered\n",
 119                     tb_port_is_dpin(port) ? "IN" : "OUT");
 120         list_add_tail(&port->list, &tcm->dp_resources);
 121 }
 122
 123 static void tb_discover_dp_resources(struct tb *tb)
 124 {
 125         struct tb_cm *tcm = tb_priv(tb);
 126         struct tb_tunnel *tunnel;
 127
 128         list_for_each_entry(tunnel, &tcm->tunnel_list, list) {
 129                 if (tb_tunnel_is_dp(tunnel))
 130                         tb_discover_dp_resource(tb, tunnel->dst_port);
 131         }
 132 }
 133
 134 static void tb_switch_discover_tunnels(struct tb_switch *sw,
 135                                        struct list_head *list,
 136                                        bool alloc_hopids)
 137 {
 138         struct tb *tb = sw->tb;
 139         struct tb_port *port;
 140
 141         tb_switch_for_each_port(sw, port) {
 142                 struct tb_tunnel *tunnel = NULL;
 143
 144                 switch (port->config.type) {
 145                 case TB_TYPE_DP_HDMI_IN:
 146                         tunnel = tb_tunnel_discover_dp(tb, port, alloc_hopids);
 147                         /*
 148                          * In case of DP tunnel exists, change host router's
 149                          * 1st children TMU mode to HiFi for CL0s to work.
 150                          */
 151                         if (tunnel)
 152                                 tb_switch_enable_tmu_1st_child(tb->root_switch,
 153                                                 TB_SWITCH_TMU_RATE_HIFI);
 154                         break;
 155
 156                 case TB_TYPE_PCIE_DOWN:
 157                         tunnel = tb_tunnel_discover_pci(tb, port, alloc_hopids);
 158                         break;
 159
 160                 case TB_TYPE_USB3_DOWN:
 161                         tunnel = tb_tunnel_discover_usb3(tb, port, alloc_hopids);
 162                         break;
 163
 164                 default:
 165                         break;
 166                 }
 167
 168                 if (tunnel)
 169                         list_add_tail(&tunnel->list, list);
 170         }
 171
 172         tb_switch_for_each_port(sw, port) {
 173                 if (tb_port_has_remote(port)) {
 174                         tb_switch_discover_tunnels(port->remote->sw, list,
 175                                                    alloc_hopids);
 176                 }
 177         }
 178 }
 179
 180 static void tb_discover_tunnels(struct tb *tb)
 181 {
 182         struct tb_cm *tcm = tb_priv(tb);
 183         struct tb_tunnel *tunnel;
 184
 185         tb_switch_discover_tunnels(tb->root_switch, &tcm->tunnel_list, true);
 186
 187         list_for_each_entry(tunnel, &tcm->tunnel_list, list) {
 188                 if (tb_tunnel_is_pci(tunnel)) {
 189                         struct tb_switch *parent = tunnel->dst_port->sw;
 190
 191                         while (parent != tunnel->src_port->sw) {
 192                                 parent->boot = true;
 193                                 parent = tb_switch_parent(parent);
 194                         }
 195                 } else if (tb_tunnel_is_dp(tunnel)) {
 196                         /* Keep the domain from powering down */
 197                         pm_runtime_get_sync(&tunnel->src_port->sw->dev);
 198                         pm_runtime_get_sync(&tunnel->dst_port->sw->dev);
 199                 }
 200         }
 201 }
 202
 203 static int tb_port_configure_xdomain(struct tb_port *port, struct tb_xdomain *xd)
 204 {
 205         if (tb_switch_is_usb4(port->sw))
 206                 return usb4_port_configure_xdomain(port, xd);
 207         return tb_lc_configure_xdomain(port);
 208 }
 209
 210 static void tb_port_unconfigure_xdomain(struct tb_port *port)
 211 {
 212         if (tb_switch_is_usb4(port->sw))
 213                 usb4_port_unconfigure_xdomain(port);
 214         else
 215                 tb_lc_unconfigure_xdomain(port);
 216
 217         tb_port_enable(port->dual_link_port);
 218 }
 219
 220 static void tb_scan_xdomain(struct tb_port *port)
 221 {
 222         struct tb_switch *sw = port->sw;
 223         struct tb *tb = sw->tb;
 224         struct tb_xdomain *xd;
 225         u64 route;
 226
 227         if (!tb_is_xdomain_enabled())
 228                 return;
 229
 230         route = tb_downstream_route(port);
 231         xd = tb_xdomain_find_by_route(tb, route);
 232         if (xd) {
 233                 tb_xdomain_put(xd);
 234                 return;
 235         }
 236
 237         xd = tb_xdomain_alloc(tb, &sw->dev, route, tb->root_switch->uuid,
 238                               NULL);
 239         if (xd) {
 240                 tb_port_at(route, sw)->xdomain = xd;
 241                 tb_port_configure_xdomain(port, xd);
 242                 tb_xdomain_add(xd);
 243         }
 244 }
 245
 246 static int tb_enable_tmu(struct tb_switch *sw)
 247 {
 248         int ret;
 249
 250         /* If it is already enabled in correct mode, don't touch it */
 251         if (tb_switch_tmu_is_enabled(sw, sw->tmu.unidirectional_request))
 252                 return 0;
 253
 254         ret = tb_switch_tmu_disable(sw);
 255         if (ret)
 256                 return ret;
 257
 258         ret = tb_switch_tmu_post_time(sw);
 259         if (ret)
 260                 return ret;
 261
 262         return tb_switch_tmu_enable(sw);
 263 }
 264
 265 /**
 266  * tb_find_unused_port() - return the first inactive port on @sw
 267  * @sw: Switch to find the port on
 268  * @type: Port type to look for
 269  */
 270 static struct tb_port *tb_find_unused_port(struct tb_switch *sw,
 271                                            enum tb_port_type type)
 272 {
 273         struct tb_port *port;
 274
 275         tb_switch_for_each_port(sw, port) {
 276                 if (tb_is_upstream_port(port))
 277                         continue;
 278                 if (port->config.type != type)
 279                         continue;
 280                 if (!port->cap_adap)
 281                         continue;
 282                 if (tb_port_is_enabled(port))
 283                         continue;
 284                 return port;
 285         }
 286         return NULL;
 287 }
 288
 289 static struct tb_port *tb_find_usb3_down(struct tb_switch *sw,
 290                                          const struct tb_port *port)
 291 {
 292         struct tb_port *down;
 293
 294         down = usb4_switch_map_usb3_down(sw, port);
 295         if (down && !tb_usb3_port_is_enabled(down))
 296                 return down;
 297         return NULL;
 298 }
 299
 300 static struct tb_tunnel *tb_find_tunnel(struct tb *tb, enum tb_tunnel_type type,
 301                                         struct tb_port *src_port,
 302                                         struct tb_port *dst_port)
 303 {
 304         struct tb_cm *tcm = tb_priv(tb);
 305         struct tb_tunnel *tunnel;
 306
 307         list_for_each_entry(tunnel, &tcm->tunnel_list, list) {
 308                 if (tunnel->type == type &&
 309                     ((src_port && src_port == tunnel->src_port) ||
 310                      (dst_port && dst_port == tunnel->dst_port))) {
 311                         return tunnel;
 312                 }
 313         }
 314
 315         return NULL;
 316 }
 317
 318 static struct tb_tunnel *tb_find_first_usb3_tunnel(struct tb *tb,
 319                                                    struct tb_port *src_port,
 320                                                    struct tb_port *dst_port)
 321 {
 322         struct tb_port *port, *usb3_down;
 323         struct tb_switch *sw;
 324
 325         /* Pick the router that is deepest in the topology */
 326         if (dst_port->sw->config.depth > src_port->sw->config.depth)
 327                 sw = dst_port->sw;
 328         else
 329                 sw = src_port->sw;
 330
 331         /* Can't be the host router */
 332         if (sw == tb->root_switch)
 333                 return NULL;
 334
 335         /* Find the downstream USB4 port that leads to this router */
 336         port = tb_port_at(tb_route(sw), tb->root_switch);
 337         /* Find the corresponding host router USB3 downstream port */
 338         usb3_down = usb4_switch_map_usb3_down(tb->root_switch, port);
 339         if (!usb3_down)
 340                 return NULL;
 341
 342         return tb_find_tunnel(tb, TB_TUNNEL_USB3, usb3_down, NULL);
 343 }
 344
 345 static int tb_available_bandwidth(struct tb *tb, struct tb_port *src_port,
 346         struct tb_port *dst_port, int *available_up, int *available_down)
 347 {
 348         int usb3_consumed_up, usb3_consumed_down, ret;
 349         struct tb_cm *tcm = tb_priv(tb);
 350         struct tb_tunnel *tunnel;
 351         struct tb_port *port;
 352
 353         tb_port_dbg(dst_port, "calculating available bandwidth\n");
 354
 355         tunnel = tb_find_first_usb3_tunnel(tb, src_port, dst_port);
 356         if (tunnel) {
 357                 ret = tb_tunnel_consumed_bandwidth(tunnel, &usb3_consumed_up,
 358                                                    &usb3_consumed_down);
 359                 if (ret)
 360                         return ret;
 361         } else {
 362                 usb3_consumed_up = 0;
 363                 usb3_consumed_down = 0;
 364         }
 365
 366         *available_up = *available_down = 40000;
 367
 368         /* Find the minimum available bandwidth over all links */
 369         tb_for_each_port_on_path(src_port, dst_port, port) {
 370                 int link_speed, link_width, up_bw, down_bw;
 371
 372                 if (!tb_port_is_null(port))
 373                         continue;
 374
 375                 if (tb_is_upstream_port(port)) {
 376                         link_speed = port->sw->link_speed;
 377                 } else {
 378                         link_speed = tb_port_get_link_speed(port);
 379                         if (link_speed < 0)
 380                                 return link_speed;
 381                 }
 382
 383                 link_width = port->bonded ? 2 : 1;
 384
 385                 up_bw = link_speed * link_width * 1000; /* Mb/s */
 386                 /* Leave 10% guard band */
 387                 up_bw -= up_bw / 10;
 388                 down_bw = up_bw;
 389
 390                 tb_port_dbg(port, "link total bandwidth %d Mb/s\n", up_bw);
 391
 392                 /*
 393                  * Find all DP tunnels that cross the port and reduce
 394                  * their consumed bandwidth from the available.
 395                  */
 396                 list_for_each_entry(tunnel, &tcm->tunnel_list, list) {
 397                         int dp_consumed_up, dp_consumed_down;
 398
 399                         if (!tb_tunnel_is_dp(tunnel))
 400                                 continue;
 401
 402                         if (!tb_tunnel_port_on_path(tunnel, port))
 403                                 continue;
 404
 405                         ret = tb_tunnel_consumed_bandwidth(tunnel,
 406                                                            &dp_consumed_up,
 407                                                            &dp_consumed_down);
 408                         if (ret)
 409                                 return ret;
 410
 411                         up_bw -= dp_consumed_up;
 412                         down_bw -= dp_consumed_down;
 413                 }
 414
 415                 /*
 416                  * If USB3 is tunneled from the host router down to the
 417                  * branch leading to port we need to take USB3 consumed
 418                  * bandwidth into account regardless whether it actually
 419                  * crosses the port.
 420                  */
 421                 up_bw -= usb3_consumed_up;
 422                 down_bw -= usb3_consumed_down;
 423
 424                 if (up_bw < *available_up)
 425                         *available_up = up_bw;
 426                 if (down_bw < *available_down)
 427                         *available_down = down_bw;
 428         }
 429
 430         if (*available_up < 0)
 431                 *available_up = 0;
 432         if (*available_down < 0)
 433                 *available_down = 0;
 434
 435         return 0;
 436 }
 437
 438 static int tb_release_unused_usb3_bandwidth(struct tb *tb,
 439                                             struct tb_port *src_port,
 440                                             struct tb_port *dst_port)
 441 {
 442         struct tb_tunnel *tunnel;
 443
 444         tunnel = tb_find_first_usb3_tunnel(tb, src_port, dst_port);
 445         return tunnel ? tb_tunnel_release_unused_bandwidth(tunnel) : 0;
 446 }
 447
 448 static void tb_reclaim_usb3_bandwidth(struct tb *tb, struct tb_port *src_port,
 449                                       struct tb_port *dst_port)
 450 {
 451         int ret, available_up, available_down;
 452         struct tb_tunnel *tunnel;
 453
 454         tunnel = tb_find_first_usb3_tunnel(tb, src_port, dst_port);
 455         if (!tunnel)
 456                 return;
 457
 458         tb_dbg(tb, "reclaiming unused bandwidth for USB3\n");
 459
 460         /*
 461          * Calculate available bandwidth for the first hop USB3 tunnel.
 462          * That determines the whole USB3 bandwidth for this branch.
 463          */
 464         ret = tb_available_bandwidth(tb, tunnel->src_port, tunnel->dst_port,
 465                                      &available_up, &available_down);
 466         if (ret) {
 467                 tb_warn(tb, "failed to calculate available bandwidth\n");
 468                 return;
 469         }
 470
 471         tb_dbg(tb, "available bandwidth for USB3 %d/%d Mb/s\n",
 472                available_up, available_down);
 473
 474         tb_tunnel_reclaim_available_bandwidth(tunnel, &available_up, &available_down);
 475 }
 476
 477 static int tb_tunnel_usb3(struct tb *tb, struct tb_switch *sw)
 478 {
 479         struct tb_switch *parent = tb_switch_parent(sw);
 480         int ret, available_up, available_down;
 481         struct tb_port *up, *down, *port;
 482         struct tb_cm *tcm = tb_priv(tb);
 483         struct tb_tunnel *tunnel;
 484
 485         if (!tb_acpi_may_tunnel_usb3()) {
 486                 tb_dbg(tb, "USB3 tunneling disabled, not creating tunnel\n");
 487                 return 0;
 488         }
 489
 490         up = tb_switch_find_port(sw, TB_TYPE_USB3_UP);
 491         if (!up)
 492                 return 0;
 493
 494         if (!sw->link_usb4)
 495                 return 0;
 496
 497         /*
 498          * Look up available down port. Since we are chaining it should
 499          * be found right above this switch.
 500          */
 501         port = tb_port_at(tb_route(sw), parent);
 502         down = tb_find_usb3_down(parent, port);
 503         if (!down)
 504                 return 0;
 505
 506         if (tb_route(parent)) {
 507                 struct tb_port *parent_up;
 508                 /*
 509                  * Check first that the parent switch has its upstream USB3
 510                  * port enabled. Otherwise the chain is not complete and
 511                  * there is no point setting up a new tunnel.
 512                  */
 513                 parent_up = tb_switch_find_port(parent, TB_TYPE_USB3_UP);
 514                 if (!parent_up || !tb_port_is_enabled(parent_up))
 515                         return 0;
 516
 517                 /* Make all unused bandwidth available for the new tunnel */
 518                 ret = tb_release_unused_usb3_bandwidth(tb, down, up);
 519                 if (ret)
 520                         return ret;
 521         }
 522
 523         ret = tb_available_bandwidth(tb, down, up, &available_up,
 524                                      &available_down);
 525         if (ret)
 526                 goto err_reclaim;
 527
 528         tb_port_dbg(up, "available bandwidth for new USB3 tunnel %d/%d Mb/s\n",
 529                     available_up, available_down);
 530
 531         tunnel = tb_tunnel_alloc_usb3(tb, up, down, available_up,
 532                                       available_down);
 533         if (!tunnel) {
 534                 ret = -ENOMEM;
 535                 goto err_reclaim;
 536         }
 537
 538         if (tb_tunnel_activate(tunnel)) {
 539                 tb_port_info(up,
 540                              "USB3 tunnel activation failed, aborting\n");
 541                 ret = -EIO;
 542                 goto err_free;
 543         }
 544
 545         list_add_tail(&tunnel->list, &tcm->tunnel_list);
 546         if (tb_route(parent))
 547                 tb_reclaim_usb3_bandwidth(tb, down, up);
 548
 549         return 0;
 550
 551 err_free:
 552         tb_tunnel_free(tunnel);
 553 err_reclaim:
 554         if (tb_route(parent))
 555                 tb_reclaim_usb3_bandwidth(tb, down, up);
 556
 557         return ret;
 558 }
 559
 560 static int tb_create_usb3_tunnels(struct tb_switch *sw)
 561 {
 562         struct tb_port *port;
 563         int ret;
 564
 565         if (!tb_acpi_may_tunnel_usb3())
 566                 return 0;
 567
 568         if (tb_route(sw)) {
 569                 ret = tb_tunnel_usb3(sw->tb, sw);
 570                 if (ret)
 571                         return ret;
 572         }
 573
 574         tb_switch_for_each_port(sw, port) {
 575                 if (!tb_port_has_remote(port))
 576                         continue;
 577                 ret = tb_create_usb3_tunnels(port->remote->sw);
 578                 if (ret)
 579                         return ret;
 580         }
 581
 582         return 0;
 583 }
 584
 585 static void tb_scan_port(struct tb_port *port);
 586
 587 /*
 588  * tb_scan_switch() - scan for and initialize downstream switches
 589  */
 590 static void tb_scan_switch(struct tb_switch *sw)
 591 {
 592         struct tb_port *port;
 593
 594         pm_runtime_get_sync(&sw->dev);
 595
 596         tb_switch_for_each_port(sw, port)
 597                 tb_scan_port(port);
 598
 599         pm_runtime_mark_last_busy(&sw->dev);
 600         pm_runtime_put_autosuspend(&sw->dev);
 601 }
 602
 603 /*
 604  * tb_scan_port() - check for and initialize switches below port
 605  */
 606 static void tb_scan_port(struct tb_port *port)
 607 {
 608         struct tb_cm *tcm = tb_priv(port->sw->tb);
 609         struct tb_port *upstream_port;
 610         struct tb_switch *sw;
 611         int ret;
 612
 613         if (tb_is_upstream_port(port))
 614                 return;
 615
 616         if (tb_port_is_dpout(port) && tb_dp_port_hpd_is_active(port) == 1 &&
 617             !tb_dp_port_is_enabled(port)) {
 618                 tb_port_dbg(port, "DP adapter HPD set, queuing hotplug\n");
 619                 tb_queue_hotplug(port->sw->tb, tb_route(port->sw), port->port,
 620                                  false);
 621                 return;
 622         }
 623
 624         if (port->config.type != TB_TYPE_PORT)
 625                 return;
 626         if (port->dual_link_port && port->link_nr)
 627                 return; /*
 628                          * Downstream switch is reachable through two ports.
 629                          * Only scan on the primary port (link_nr == 0).
 630                          */
 631
 632         if (port->usb4)
 633                 pm_runtime_get_sync(&port->usb4->dev);
 634
 635         if (tb_wait_for_port(port, false) <= 0)
 636                 goto out_rpm_put;
 637         if (port->remote) {
 638                 tb_port_dbg(port, "port already has a remote\n");
 639                 goto out_rpm_put;
 640         }
 641
 642         tb_retimer_scan(port, true);
 643
 644         sw = tb_switch_alloc(port->sw->tb, &port->sw->dev,
 645                              tb_downstream_route(port));
 646         if (IS_ERR(sw)) {
 647                 /*
 648                  * If there is an error accessing the connected switch
 649                  * it may be connected to another domain. Also we allow
 650                  * the other domain to be connected to a max depth switch.
 651                  */
 652                 if (PTR_ERR(sw) == -EIO || PTR_ERR(sw) == -EADDRNOTAVAIL)
 653                         tb_scan_xdomain(port);
 654                 goto out_rpm_put;
 655         }
 656
 657         if (tb_switch_configure(sw)) {
 658                 tb_switch_put(sw);
 659                 goto out_rpm_put;
 660         }
 661
 662         /*
 663          * If there was previously another domain connected remove it
 664          * first.
 665          */
 666         if (port->xdomain) {
 667                 tb_xdomain_remove(port->xdomain);
 668                 tb_port_unconfigure_xdomain(port);
 669                 port->xdomain = NULL;
 670         }
 671
 672         /*
 673          * Do not send uevents until we have discovered all existing
 674          * tunnels and know which switches were authorized already by
 675          * the boot firmware.
 676          */
 677         if (!tcm->hotplug_active)
 678                 dev_set_uevent_suppress(&sw->dev, true);
 679
 680         /*
 681          * At the moment Thunderbolt 2 and beyond (devices with LC) we
 682          * can support runtime PM.
 683          */
 684         sw->rpm = sw->generation > 1;
 685
 686         if (tb_switch_add(sw)) {
 687                 tb_switch_put(sw);
 688                 goto out_rpm_put;
 689         }
 690
 691         /* Link the switches using both links if available */
 692         upstream_port = tb_upstream_port(sw);
 693         port->remote = upstream_port;
 694         upstream_port->remote = port;
 695         if (port->dual_link_port && upstream_port->dual_link_port) {
 696                 port->dual_link_port->remote = upstream_port->dual_link_port;
 697                 upstream_port->dual_link_port->remote = port->dual_link_port;
 698         }
 699
 700         /* Enable lane bonding if supported */
 701         tb_switch_lane_bonding_enable(sw);
 702         /* Set the link configured */
 703         tb_switch_configure_link(sw);
 704         /*
 705          * CL0s and CL1 are enabled and supported together.
 706          * Silently ignore CLx enabling in case CLx is not supported.
 707          */
 708         ret = tb_switch_enable_clx(sw, TB_CL1);
 709         if (ret && ret != -EOPNOTSUPP)
 710                 tb_sw_warn(sw, "failed to enable %s on upstream port\n",
 711                            tb_switch_clx_name(TB_CL1));
 712
 713         if (tb_switch_is_clx_enabled(sw, TB_CL1))
 714                 /*
 715                  * To support highest CLx state, we set router's TMU to
 716                  * Normal-Uni mode.
 717                  */
 718                 tb_switch_tmu_configure(sw, TB_SWITCH_TMU_RATE_NORMAL, true);
 719         else
 720                 /* If CLx disabled, configure router's TMU to HiFi-Bidir mode*/
 721                 tb_switch_tmu_configure(sw, TB_SWITCH_TMU_RATE_HIFI, false);
 722
 723         if (tb_enable_tmu(sw))
 724                 tb_sw_warn(sw, "failed to enable TMU\n");
 725
 726         /* Scan upstream retimers */
 727         tb_retimer_scan(upstream_port, true);
 728
 729         /*
 730          * Create USB 3.x tunnels only when the switch is plugged to the
 731          * domain. This is because we scan the domain also during discovery
 732          * and want to discover existing USB 3.x tunnels before we create
 733          * any new.
 734          */
 735         if (tcm->hotplug_active && tb_tunnel_usb3(sw->tb, sw))
 736                 tb_sw_warn(sw, "USB3 tunnel creation failed\n");
 737
 738         tb_add_dp_resources(sw);
 739         tb_scan_switch(sw);
 740
 741 out_rpm_put:
 742         if (port->usb4) {
 743                 pm_runtime_mark_last_busy(&port->usb4->dev);
 744                 pm_runtime_put_autosuspend(&port->usb4->dev);
 745         }
 746 }
 747
 748 static void tb_deactivate_and_free_tunnel(struct tb_tunnel *tunnel)
 749 {
 750         struct tb_port *src_port, *dst_port;
 751         struct tb *tb;
 752
 753         if (!tunnel)
 754                 return;
 755
 756         tb_tunnel_deactivate(tunnel);
 757         list_del(&tunnel->list);
 758
 759         tb = tunnel->tb;
 760         src_port = tunnel->src_port;
 761         dst_port = tunnel->dst_port;
 762
 763         switch (tunnel->type) {
 764         case TB_TUNNEL_DP:
 765                 /*
 766                  * In case of DP tunnel make sure the DP IN resource is
 767                  * deallocated properly.
 768                  */
 769                 tb_switch_dealloc_dp_resource(src_port->sw, src_port);
 770                 /* Now we can allow the domain to runtime suspend again */
 771                 pm_runtime_mark_last_busy(&dst_port->sw->dev);
 772                 pm_runtime_put_autosuspend(&dst_port->sw->dev);
 773                 pm_runtime_mark_last_busy(&src_port->sw->dev);
 774                 pm_runtime_put_autosuspend(&src_port->sw->dev);
 775                 fallthrough;
 776
 777         case TB_TUNNEL_USB3:
 778                 tb_reclaim_usb3_bandwidth(tb, src_port, dst_port);
 779                 break;
 780
 781         default:
 782                 /*
 783                  * PCIe and DMA tunnels do not consume guaranteed
 784                  * bandwidth.
 785                  */
 786                 break;
 787         }
 788
 789         tb_tunnel_free(tunnel);
 790 }
 791
 792 /*
 793  * tb_free_invalid_tunnels() - destroy tunnels of devices that have gone away
 794  */
 795 static void tb_free_invalid_tunnels(struct tb *tb)
 796 {
 797         struct tb_cm *tcm = tb_priv(tb);
 798         struct tb_tunnel *tunnel;
 799         struct tb_tunnel *n;
 800
 801         list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) {
 802                 if (tb_tunnel_is_invalid(tunnel))
 803                         tb_deactivate_and_free_tunnel(tunnel);
 804         }
 805 }
 806
 807 /*
 808  * tb_free_unplugged_children() - traverse hierarchy and free unplugged switches
 809  */
 810 static void tb_free_unplugged_children(struct tb_switch *sw)
 811 {
 812         struct tb_port *port;
 813
 814         tb_switch_for_each_port(sw, port) {
 815                 if (!tb_port_has_remote(port))
 816                         continue;
 817
 818                 if (port->remote->sw->is_unplugged) {
 819                         tb_retimer_remove_all(port);
 820                         tb_remove_dp_resources(port->remote->sw);
 821                         tb_switch_unconfigure_link(port->remote->sw);
 822                         tb_switch_lane_bonding_disable(port->remote->sw);
 823                         tb_switch_remove(port->remote->sw);
 824                         port->remote = NULL;
 825                         if (port->dual_link_port)
 826                                 port->dual_link_port->remote = NULL;
 827                 } else {
 828                         tb_free_unplugged_children(port->remote->sw);
 829                 }
 830         }
 831 }
 832
 833 static struct tb_port *tb_find_pcie_down(struct tb_switch *sw,
 834                                          const struct tb_port *port)
 835 {
 836         struct tb_port *down = NULL;
 837
 838         /*
 839          * To keep plugging devices consistently in the same PCIe
 840          * hierarchy, do mapping here for switch downstream PCIe ports.
 841          */
 842         if (tb_switch_is_usb4(sw)) {
 843                 down = usb4_switch_map_pcie_down(sw, port);
 844         } else if (!tb_route(sw)) {
 845                 int phy_port = tb_phy_port_from_link(port->port);
 846                 int index;
 847
 848                 /*
 849                  * Hard-coded Thunderbolt port to PCIe down port mapping
 850                  * per controller.
 851                  */
 852                 if (tb_switch_is_cactus_ridge(sw) ||
 853                     tb_switch_is_alpine_ridge(sw))
 854                         index = !phy_port ? 6 : 7;
 855                 else if (tb_switch_is_falcon_ridge(sw))
 856                         index = !phy_port ? 6 : 8;
 857                 else if (tb_switch_is_titan_ridge(sw))
 858                         index = !phy_port ? 8 : 9;
 859                 else
 860                         goto out;
 861
 862                 /* Validate the hard-coding */
 863                 if (WARN_ON(index > sw->config.max_port_number))
 864                         goto out;
 865
 866                 down = &sw->ports[index];
 867         }
 868
 869         if (down) {
 870                 if (WARN_ON(!tb_port_is_pcie_down(down)))
 871                         goto out;
 872                 if (tb_pci_port_is_enabled(down))
 873                         goto out;
 874
 875                 return down;
 876         }
 877
 878 out:
 879         return tb_find_unused_port(sw, TB_TYPE_PCIE_DOWN);
 880 }
 881
 882 static struct tb_port *tb_find_dp_out(struct tb *tb, struct tb_port *in)
 883 {
 884         struct tb_port *host_port, *port;
 885         struct tb_cm *tcm = tb_priv(tb);
 886
 887         host_port = tb_route(in->sw) ?
 888                 tb_port_at(tb_route(in->sw), tb->root_switch) : NULL;
 889
 890         list_for_each_entry(port, &tcm->dp_resources, list) {
 891                 if (!tb_port_is_dpout(port))
 892                         continue;
 893
 894                 if (tb_port_is_enabled(port)) {
 895                         tb_port_dbg(port, "in use\n");
 896                         continue;
 897                 }
 898
 899                 tb_port_dbg(port, "DP OUT available\n");
 900
 901                 /*
 902                  * Keep the DP tunnel under the topology starting from
 903                  * the same host router downstream port.
 904                  */
 905                 if (host_port && tb_route(port->sw)) {
 906                         struct tb_port *p;
 907
 908                         p = tb_port_at(tb_route(port->sw), tb->root_switch);
 909                         if (p != host_port)
 910                                 continue;
 911                 }
 912
 913                 return port;
 914         }
 915
 916         return NULL;
 917 }
 918
 919 static void tb_tunnel_dp(struct tb *tb)
 920 {
 921         int available_up, available_down, ret, link_nr;
 922         struct tb_cm *tcm = tb_priv(tb);
 923         struct tb_port *port, *in, *out;
 924         struct tb_tunnel *tunnel;
 925
 926         if (!tb_acpi_may_tunnel_dp()) {
 927                 tb_dbg(tb, "DP tunneling disabled, not creating tunnel\n");
 928                 return;
 929         }
 930
 931         /*
 932          * Find pair of inactive DP IN and DP OUT adapters and then
 933          * establish a DP tunnel between them.
 934          */
 935         tb_dbg(tb, "looking for DP IN <-> DP OUT pairs:\n");
 936
 937         in = NULL;
 938         out = NULL;
 939         list_for_each_entry(port, &tcm->dp_resources, list) {
 940                 if (!tb_port_is_dpin(port))
 941                         continue;
 942
 943                 if (tb_port_is_enabled(port)) {
 944                         tb_port_dbg(port, "in use\n");
 945                         continue;
 946                 }
 947
 948                 tb_port_dbg(port, "DP IN available\n");
 949
 950                 out = tb_find_dp_out(tb, port);
 951                 if (out) {
 952                         in = port;
 953                         break;
 954                 }
 955         }
 956
 957         if (!in) {
 958                 tb_dbg(tb, "no suitable DP IN adapter available, not tunneling\n");
 959                 return;
 960         }
 961         if (!out) {
 962                 tb_dbg(tb, "no suitable DP OUT adapter available, not tunneling\n");
 963                 return;
 964         }
 965
 966         /*
 967          * This is only applicable to links that are not bonded (so
 968          * when Thunderbolt 1 hardware is involved somewhere in the
 969          * topology). For these try to share the DP bandwidth between
 970          * the two lanes.
 971          */
 972         link_nr = 1;
 973         list_for_each_entry(tunnel, &tcm->tunnel_list, list) {
 974                 if (tb_tunnel_is_dp(tunnel)) {
 975                         link_nr = 0;
 976                         break;
 977                 }
 978         }
 979
 980         /*
 981          * DP stream needs the domain to be active so runtime resume
 982          * both ends of the tunnel.
 983          *
 984          * This should bring the routers in the middle active as well
 985          * and keeps the domain from runtime suspending while the DP
 986          * tunnel is active.
 987          */
 988         pm_runtime_get_sync(&in->sw->dev);
 989         pm_runtime_get_sync(&out->sw->dev);
 990
 991         if (tb_switch_alloc_dp_resource(in->sw, in)) {
 992                 tb_port_dbg(in, "no resource available for DP IN, not tunneling\n");
 993                 goto err_rpm_put;
 994         }
 995
 996         /* Make all unused USB3 bandwidth available for the new DP tunnel */
 997         ret = tb_release_unused_usb3_bandwidth(tb, in, out);
 998         if (ret) {
 999                 tb_warn(tb, "failed to release unused bandwidth\n");
1000                 goto err_dealloc_dp;
1001         }
1002
1003         ret = tb_available_bandwidth(tb, in, out, &available_up,
1004                                      &available_down);
1005         if (ret)
1006                 goto err_reclaim;
1007
1008         tb_dbg(tb, "available bandwidth for new DP tunnel %u/%u Mb/s\n",
1009                available_up, available_down);
1010
1011         tunnel = tb_tunnel_alloc_dp(tb, in, out, link_nr, available_up,
1012                                     available_down);
1013         if (!tunnel) {
1014                 tb_port_dbg(out, "could not allocate DP tunnel\n");
1015                 goto err_reclaim;
1016         }
1017
1018         if (tb_tunnel_activate(tunnel)) {
1019                 tb_port_info(out, "DP tunnel activation failed, aborting\n");
1020                 goto err_free;
1021         }
1022
1023         list_add_tail(&tunnel->list, &tcm->tunnel_list);
1024         tb_reclaim_usb3_bandwidth(tb, in, out);
1025         /*
1026          * In case of DP tunnel exists, change host router's 1st children
1027          * TMU mode to HiFi for CL0s to work.
1028          */
1029         tb_switch_enable_tmu_1st_child(tb->root_switch, TB_SWITCH_TMU_RATE_HIFI);
1030
1031         return;
1032
1033 err_free:
1034         tb_tunnel_free(tunnel);
1035 err_reclaim:
1036         tb_reclaim_usb3_bandwidth(tb, in, out);
1037 err_dealloc_dp:
1038         tb_switch_dealloc_dp_resource(in->sw, in);
1039 err_rpm_put:
1040         pm_runtime_mark_last_busy(&out->sw->dev);
1041         pm_runtime_put_autosuspend(&out->sw->dev);
1042         pm_runtime_mark_last_busy(&in->sw->dev);
1043         pm_runtime_put_autosuspend(&in->sw->dev);
1044 }
1045
1046 static void tb_dp_resource_unavailable(struct tb *tb, struct tb_port *port)
1047 {
1048         struct tb_port *in, *out;
1049         struct tb_tunnel *tunnel;
1050
1051         if (tb_port_is_dpin(port)) {
1052                 tb_port_dbg(port, "DP IN resource unavailable\n");
1053                 in = port;
1054                 out = NULL;
1055         } else {
1056                 tb_port_dbg(port, "DP OUT resource unavailable\n");
1057                 in = NULL;
1058                 out = port;
1059         }
1060
1061         tunnel = tb_find_tunnel(tb, TB_TUNNEL_DP, in, out);
1062         tb_deactivate_and_free_tunnel(tunnel);
1063         list_del_init(&port->list);
1064
1065         /*
1066          * See if there is another DP OUT port that can be used for
1067          * to create another tunnel.
1068          */
1069         tb_tunnel_dp(tb);
1070 }
1071
1072 static void tb_dp_resource_available(struct tb *tb, struct tb_port *port)
1073 {
1074         struct tb_cm *tcm = tb_priv(tb);
1075         struct tb_port *p;
1076
1077         if (tb_port_is_enabled(port))
1078                 return;
1079
1080         list_for_each_entry(p, &tcm->dp_resources, list) {
1081                 if (p == port)
1082                         return;
1083         }
1084
1085         tb_port_dbg(port, "DP %s resource available\n",
1086                     tb_port_is_dpin(port) ? "IN" : "OUT");
1087         list_add_tail(&port->list, &tcm->dp_resources);
1088
1089         /* Look for suitable DP IN <-> DP OUT pairs now */
1090         tb_tunnel_dp(tb);
1091 }
1092
1093 static void tb_disconnect_and_release_dp(struct tb *tb)
1094 {
1095         struct tb_cm *tcm = tb_priv(tb);
1096         struct tb_tunnel *tunnel, *n;
1097
1098         /*
1099          * Tear down all DP tunnels and release their resources. They
1100          * will be re-established after resume based on plug events.
1101          */
1102         list_for_each_entry_safe_reverse(tunnel, n, &tcm->tunnel_list, list) {
1103                 if (tb_tunnel_is_dp(tunnel))
1104                         tb_deactivate_and_free_tunnel(tunnel);
1105         }
1106
1107         while (!list_empty(&tcm->dp_resources)) {
1108                 struct tb_port *port;
1109
1110                 port = list_first_entry(&tcm->dp_resources,
1111                                         struct tb_port, list);
1112                 list_del_init(&port->list);
1113         }
1114 }
1115
1116 static int tb_disconnect_pci(struct tb *tb, struct tb_switch *sw)
1117 {
1118         struct tb_tunnel *tunnel;
1119         struct tb_port *up;
1120
1121         up = tb_switch_find_port(sw, TB_TYPE_PCIE_UP);
1122         if (WARN_ON(!up))
1123                 return -ENODEV;
1124
1125         tunnel = tb_find_tunnel(tb, TB_TUNNEL_PCI, NULL, up);
1126         if (WARN_ON(!tunnel))
1127                 return -ENODEV;
1128
1129         tb_switch_xhci_disconnect(sw);
1130
1131         tb_tunnel_deactivate(tunnel);
1132         list_del(&tunnel->list);
1133         tb_tunnel_free(tunnel);
1134         return 0;
1135 }
1136
1137 static int tb_tunnel_pci(struct tb *tb, struct tb_switch *sw)
1138 {
1139         struct tb_port *up, *down, *port;
1140         struct tb_cm *tcm = tb_priv(tb);
1141         struct tb_switch *parent_sw;
1142         struct tb_tunnel *tunnel;
1143
1144         up = tb_switch_find_port(sw, TB_TYPE_PCIE_UP);
1145         if (!up)
1146                 return 0;
1147
1148         /*
1149          * Look up available down port. Since we are chaining it should
1150          * be found right above this switch.
1151          */
1152         parent_sw = tb_to_switch(sw->dev.parent);
1153         port = tb_port_at(tb_route(sw), parent_sw);
1154         down = tb_find_pcie_down(parent_sw, port);
1155         if (!down)
1156                 return 0;
1157
1158         tunnel = tb_tunnel_alloc_pci(tb, up, down);
1159         if (!tunnel)
1160                 return -ENOMEM;
1161
1162         if (tb_tunnel_activate(tunnel)) {
1163                 tb_port_info(up,
1164                              "PCIe tunnel activation failed, aborting\n");
1165                 tb_tunnel_free(tunnel);
1166                 return -EIO;
1167         }
1168
1169         /*
1170          * PCIe L1 is needed to enable CL0s for Titan Ridge so enable it
1171          * here.
1172          */
1173         if (tb_switch_pcie_l1_enable(sw))
1174                 tb_sw_warn(sw, "failed to enable PCIe L1 for Titan Ridge\n");
1175
1176         if (tb_switch_xhci_connect(sw))
1177                 tb_sw_warn(sw, "failed to connect xHCI\n");
1178
1179         list_add_tail(&tunnel->list, &tcm->tunnel_list);
1180         return 0;
1181 }
1182
1183 static int tb_approve_xdomain_paths(struct tb *tb, struct tb_xdomain *xd,
1184                                     int transmit_path, int transmit_ring,
1185                                     int receive_path, int receive_ring)
1186 {
1187         struct tb_cm *tcm = tb_priv(tb);
1188         struct tb_port *nhi_port, *dst_port;
1189         struct tb_tunnel *tunnel;
1190         struct tb_switch *sw;
1191
1192         sw = tb_to_switch(xd->dev.parent);
1193         dst_port = tb_port_at(xd->route, sw);
1194         nhi_port = tb_switch_find_port(tb->root_switch, TB_TYPE_NHI);
1195
1196         mutex_lock(&tb->lock);
1197         tunnel = tb_tunnel_alloc_dma(tb, nhi_port, dst_port, transmit_path,
1198                                      transmit_ring, receive_path, receive_ring);
1199         if (!tunnel) {
1200                 mutex_unlock(&tb->lock);
1201                 return -ENOMEM;
1202         }
1203
1204         if (tb_tunnel_activate(tunnel)) {
1205                 tb_port_info(nhi_port,
1206                              "DMA tunnel activation failed, aborting\n");
1207                 tb_tunnel_free(tunnel);
1208                 mutex_unlock(&tb->lock);
1209                 return -EIO;
1210         }
1211
1212         list_add_tail(&tunnel->list, &tcm->tunnel_list);
1213         mutex_unlock(&tb->lock);
1214         return 0;
1215 }
1216
1217 static void __tb_disconnect_xdomain_paths(struct tb *tb, struct tb_xdomain *xd,
1218                                           int transmit_path, int transmit_ring,
1219                                           int receive_path, int receive_ring)
1220 {
1221         struct tb_cm *tcm = tb_priv(tb);
1222         struct tb_port *nhi_port, *dst_port;
1223         struct tb_tunnel *tunnel, *n;
1224         struct tb_switch *sw;
1225
1226         sw = tb_to_switch(xd->dev.parent);
1227         dst_port = tb_port_at(xd->route, sw);
1228         nhi_port = tb_switch_find_port(tb->root_switch, TB_TYPE_NHI);
1229
1230         list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) {
1231                 if (!tb_tunnel_is_dma(tunnel))
1232                         continue;
1233                 if (tunnel->src_port != nhi_port || tunnel->dst_port != dst_port)
1234                         continue;
1235
1236                 if (tb_tunnel_match_dma(tunnel, transmit_path, transmit_ring,
1237                                         receive_path, receive_ring))
1238                         tb_deactivate_and_free_tunnel(tunnel);
1239         }
1240 }
1241
1242 static int tb_disconnect_xdomain_paths(struct tb *tb, struct tb_xdomain *xd,
1243                                        int transmit_path, int transmit_ring,
1244                                        int receive_path, int receive_ring)
1245 {
1246         if (!xd->is_unplugged) {
1247                 mutex_lock(&tb->lock);
1248                 __tb_disconnect_xdomain_paths(tb, xd, transmit_path,
1249                                               transmit_ring, receive_path,
1250                                               receive_ring);
1251                 mutex_unlock(&tb->lock);
1252         }
1253         return 0;
1254 }
1255
1256 /* hotplug handling */
1257
1258 /*
1259  * tb_handle_hotplug() - handle hotplug event
1260  *
1261  * Executes on tb->wq.
1262  */
1263 static void tb_handle_hotplug(struct work_struct *work)
1264 {
1265         struct tb_hotplug_event *ev = container_of(work, typeof(*ev), work);
1266         struct tb *tb = ev->tb;
1267         struct tb_cm *tcm = tb_priv(tb);
1268         struct tb_switch *sw;
1269         struct tb_port *port;
1270
1271         /* Bring the domain back from sleep if it was suspended */
1272         pm_runtime_get_sync(&tb->dev);
1273
1274         mutex_lock(&tb->lock);
1275         if (!tcm->hotplug_active)
1276                 goto out; /* during init, suspend or shutdown */
1277
1278         sw = tb_switch_find_by_route(tb, ev->route);
1279         if (!sw) {
1280                 tb_warn(tb,
1281                         "hotplug event from non existent switch %llx:%x (unplug: %d)\n",
1282                         ev->route, ev->port, ev->unplug);
1283                 goto out;
1284         }
1285         if (ev->port > sw->config.max_port_number) {
1286                 tb_warn(tb,
1287                         "hotplug event from non existent port %llx:%x (unplug: %d)\n",
1288                         ev->route, ev->port, ev->unplug);
1289                 goto put_sw;
1290         }
1291         port = &sw->ports[ev->port];
1292         if (tb_is_upstream_port(port)) {
1293                 tb_dbg(tb, "hotplug event for upstream port %llx:%x (unplug: %d)\n",
1294                        ev->route, ev->port, ev->unplug);
1295                 goto put_sw;
1296         }
1297
1298         pm_runtime_get_sync(&sw->dev);
1299
1300         if (ev->unplug) {
1301                 tb_retimer_remove_all(port);
1302
1303                 if (tb_port_has_remote(port)) {
1304                         tb_port_dbg(port, "switch unplugged\n");
1305                         tb_sw_set_unplugged(port->remote->sw);
1306                         tb_free_invalid_tunnels(tb);
1307                         tb_remove_dp_resources(port->remote->sw);
1308                         tb_switch_tmu_disable(port->remote->sw);
1309                         tb_switch_unconfigure_link(port->remote->sw);
1310                         tb_switch_lane_bonding_disable(port->remote->sw);
1311                         tb_switch_remove(port->remote->sw);
1312                         port->remote = NULL;
1313                         if (port->dual_link_port)
1314                                 port->dual_link_port->remote = NULL;
1315                         /* Maybe we can create another DP tunnel */
1316                         tb_tunnel_dp(tb);
1317                 } else if (port->xdomain) {
1318                         struct tb_xdomain *xd = tb_xdomain_get(port->xdomain);
1319
1320                         tb_port_dbg(port, "xdomain unplugged\n");
1321                         /*
1322                          * Service drivers are unbound during
1323                          * tb_xdomain_remove() so setting XDomain as
1324                          * unplugged here prevents deadlock if they call
1325                          * tb_xdomain_disable_paths(). We will tear down
1326                          * all the tunnels below.
1327                          */
1328                         xd->is_unplugged = true;
1329                         tb_xdomain_remove(xd);
1330                         port->xdomain = NULL;
1331                         __tb_disconnect_xdomain_paths(tb, xd, -1, -1, -1, -1);
1332                         tb_xdomain_put(xd);
1333                         tb_port_unconfigure_xdomain(port);
1334                 } else if (tb_port_is_dpout(port) || tb_port_is_dpin(port)) {
1335                         tb_dp_resource_unavailable(tb, port);
1336                 } else if (!port->port) {
1337                         tb_sw_dbg(sw, "xHCI disconnect request\n");
1338                         tb_switch_xhci_disconnect(sw);
1339                 } else {
1340                         tb_port_dbg(port,
1341                                    "got unplug event for disconnected port, ignoring\n");
1342                 }
1343         } else if (port->remote) {
1344                 tb_port_dbg(port, "got plug event for connected port, ignoring\n");
1345         } else if (!port->port && sw->authorized) {
1346                 tb_sw_dbg(sw, "xHCI connect request\n");
1347                 tb_switch_xhci_connect(sw);
1348         } else {
1349                 if (tb_port_is_null(port)) {
1350                         tb_port_dbg(port, "hotplug: scanning\n");
1351                         tb_scan_port(port);
1352                         if (!port->remote)
1353                                 tb_port_dbg(port, "hotplug: no switch found\n");
1354                 } else if (tb_port_is_dpout(port) || tb_port_is_dpin(port)) {
1355                         tb_dp_resource_available(tb, port);
1356                 }
1357         }
1358
1359         pm_runtime_mark_last_busy(&sw->dev);
1360         pm_runtime_put_autosuspend(&sw->dev);
1361
1362 put_sw:
1363         tb_switch_put(sw);
1364 out:
1365         mutex_unlock(&tb->lock);
1366
1367         pm_runtime_mark_last_busy(&tb->dev);
1368         pm_runtime_put_autosuspend(&tb->dev);
1369
1370         kfree(ev);
1371 }
1372
1373 /*
1374  * tb_schedule_hotplug_handler() - callback function for the control channel
1375  *
1376  * Delegates to tb_handle_hotplug.
1377  */
1378 static void tb_handle_event(struct tb *tb, enum tb_cfg_pkg_type type,
1379                             const void *buf, size_t size)
1380 {
1381         const struct cfg_event_pkg *pkg = buf;
1382         u64 route;
1383
1384         if (type != TB_CFG_PKG_EVENT) {
1385                 tb_warn(tb, "unexpected event %#x, ignoring\n", type);
1386                 return;
1387         }
1388
1389         route = tb_cfg_get_route(&pkg->header);
1390
1391         if (tb_cfg_ack_plug(tb->ctl, route, pkg->port, pkg->unplug)) {
1392                 tb_warn(tb, "could not ack plug event on %llx:%x\n", route,
1393                         pkg->port);
1394         }
1395
1396         tb_queue_hotplug(tb, route, pkg->port, pkg->unplug);
1397 }
1398
1399 static void tb_stop(struct tb *tb)
1400 {
1401         struct tb_cm *tcm = tb_priv(tb);
1402         struct tb_tunnel *tunnel;
1403         struct tb_tunnel *n;
1404
1405         cancel_delayed_work(&tcm->remove_work);
1406         /* tunnels are only present after everything has been initialized */
1407         list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) {
1408                 /*
1409                  * DMA tunnels require the driver to be functional so we
1410                  * tear them down. Other protocol tunnels can be left
1411                  * intact.
1412                  */
1413                 if (tb_tunnel_is_dma(tunnel))
1414                         tb_tunnel_deactivate(tunnel);
1415                 tb_tunnel_free(tunnel);
1416         }
1417         tb_switch_remove(tb->root_switch);
1418         tcm->hotplug_active = false; /* signal tb_handle_hotplug to quit */
1419 }
1420
1421 static int tb_scan_finalize_switch(struct device *dev, void *data)
1422 {
1423         if (tb_is_switch(dev)) {
1424                 struct tb_switch *sw = tb_to_switch(dev);
1425
1426                 /*
1427                  * If we found that the switch was already setup by the
1428                  * boot firmware, mark it as authorized now before we
1429                  * send uevent to userspace.
1430                  */
1431                 if (sw->boot)
1432                         sw->authorized = 1;
1433
1434                 dev_set_uevent_suppress(dev, false);
1435                 kobject_uevent(&dev->kobj, KOBJ_ADD);
1436                 device_for_each_child(dev, NULL, tb_scan_finalize_switch);
1437         }
1438
1439         return 0;
1440 }
1441
1442 static int tb_start(struct tb *tb)
1443 {
1444         struct tb_cm *tcm = tb_priv(tb);
1445         int ret;
1446
1447         tb->root_switch = tb_switch_alloc(tb, &tb->dev, 0);
1448         if (IS_ERR(tb->root_switch))
1449                 return PTR_ERR(tb->root_switch);
1450
1451         /*
1452          * ICM firmware upgrade needs running firmware and in native
1453          * mode that is not available so disable firmware upgrade of the
1454          * root switch.
1455          *
1456          * However, USB4 routers support NVM firmware upgrade if they
1457          * implement the necessary router operations.
1458          */
1459         tb->root_switch->no_nvm_upgrade = !tb_switch_is_usb4(tb->root_switch);
1460         /* All USB4 routers support runtime PM */
1461         tb->root_switch->rpm = tb_switch_is_usb4(tb->root_switch);
1462
1463         ret = tb_switch_configure(tb->root_switch);
1464         if (ret) {
1465                 tb_switch_put(tb->root_switch);
1466                 return ret;
1467         }
1468
1469         /* Announce the switch to the world */
1470         ret = tb_switch_add(tb->root_switch);
1471         if (ret) {
1472                 tb_switch_put(tb->root_switch);
1473                 return ret;
1474         }
1475
1476         /*
1477          * To support highest CLx state, we set host router's TMU to
1478          * Normal mode.
1479          */
1480         tb_switch_tmu_configure(tb->root_switch, TB_SWITCH_TMU_RATE_NORMAL,
1481                                 false);
1482         /* Enable TMU if it is off */
1483         tb_switch_tmu_enable(tb->root_switch);
1484         /* Full scan to discover devices added before the driver was loaded. */
1485         tb_scan_switch(tb->root_switch);
1486         /* Find out tunnels created by the boot firmware */
1487         tb_discover_tunnels(tb);
1488         /* Add DP resources from the DP tunnels created by the boot firmware */
1489         tb_discover_dp_resources(tb);
1490         /*
1491          * If the boot firmware did not create USB 3.x tunnels create them
1492          * now for the whole topology.
1493          */
1494         tb_create_usb3_tunnels(tb->root_switch);
1495         /* Add DP IN resources for the root switch */
1496         tb_add_dp_resources(tb->root_switch);
1497         /* Make the discovered switches available to the userspace */
1498         device_for_each_child(&tb->root_switch->dev, NULL,
1499                               tb_scan_finalize_switch);
1500
1501         /* Allow tb_handle_hotplug to progress events */
1502         tcm->hotplug_active = true;
1503         return 0;
1504 }
1505
1506 static int tb_suspend_noirq(struct tb *tb)
1507 {
1508         struct tb_cm *tcm = tb_priv(tb);
1509
1510         tb_dbg(tb, "suspending...\n");
1511         tb_disconnect_and_release_dp(tb);
1512         tb_switch_suspend(tb->root_switch, false);
1513         tcm->hotplug_active = false; /* signal tb_handle_hotplug to quit */
1514         tb_dbg(tb, "suspend finished\n");
1515
1516         return 0;
1517 }
1518
1519 static void tb_restore_children(struct tb_switch *sw)
1520 {
1521         struct tb_port *port;
1522         int ret;
1523
1524         /* No need to restore if the router is already unplugged */
1525         if (sw->is_unplugged)
1526                 return;
1527
1528         /*
1529          * CL0s and CL1 are enabled and supported together.
1530          * Silently ignore CLx re-enabling in case CLx is not supported.
1531          */
1532         ret = tb_switch_enable_clx(sw, TB_CL1);
1533         if (ret && ret != -EOPNOTSUPP)
1534                 tb_sw_warn(sw, "failed to re-enable %s on upstream port\n",
1535                            tb_switch_clx_name(TB_CL1));
1536
1537         if (tb_switch_is_clx_enabled(sw, TB_CL1))
1538                 /*
1539                  * To support highest CLx state, we set router's TMU to
1540                  * Normal-Uni mode.
1541                  */
1542                 tb_switch_tmu_configure(sw, TB_SWITCH_TMU_RATE_NORMAL, true);
1543         else
1544                 /* If CLx disabled, configure router's TMU to HiFi-Bidir mode*/
1545                 tb_switch_tmu_configure(sw, TB_SWITCH_TMU_RATE_HIFI, false);
1546
1547         if (tb_enable_tmu(sw))
1548                 tb_sw_warn(sw, "failed to restore TMU configuration\n");
1549
1550         tb_switch_for_each_port(sw, port) {
1551                 if (!tb_port_has_remote(port) && !port->xdomain)
1552                         continue;
1553
1554                 if (port->remote) {
1555                         tb_switch_lane_bonding_enable(port->remote->sw);
1556                         tb_switch_configure_link(port->remote->sw);
1557
1558                         tb_restore_children(port->remote->sw);
1559                 } else if (port->xdomain) {
1560                         tb_port_configure_xdomain(port, port->xdomain);
1561                 }
1562         }
1563 }
1564
1565 static int tb_resume_noirq(struct tb *tb)
1566 {
1567         struct tb_cm *tcm = tb_priv(tb);
1568         struct tb_tunnel *tunnel, *n;
1569         unsigned int usb3_delay = 0;
1570         LIST_HEAD(tunnels);
1571
1572         tb_dbg(tb, "resuming...\n");
1573
1574         /* remove any pci devices the firmware might have setup */
1575         tb_switch_reset(tb->root_switch);
1576
1577         tb_switch_resume(tb->root_switch);
1578         tb_free_invalid_tunnels(tb);
1579         tb_free_unplugged_children(tb->root_switch);
1580         tb_restore_children(tb->root_switch);
1581
1582         /*
1583          * If we get here from suspend to disk the boot firmware or the
1584          * restore kernel might have created tunnels of its own. Since
1585          * we cannot be sure they are usable for us we find and tear
1586          * them down.
1587          */
1588         tb_switch_discover_tunnels(tb->root_switch, &tunnels, false);
1589         list_for_each_entry_safe_reverse(tunnel, n, &tunnels, list) {
1590                 if (tb_tunnel_is_usb3(tunnel))
1591                         usb3_delay = 500;
1592                 tb_tunnel_deactivate(tunnel);
1593                 tb_tunnel_free(tunnel);
1594         }
1595
1596         /* Re-create our tunnels now */
1597         list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list) {
1598                 /* USB3 requires delay before it can be re-activated */
1599                 if (tb_tunnel_is_usb3(tunnel)) {
1600                         msleep(usb3_delay);
1601                         /* Only need to do it once */
1602                         usb3_delay = 0;
1603                 }
1604                 tb_tunnel_restart(tunnel);
1605         }
1606         if (!list_empty(&tcm->tunnel_list)) {
1607                 /*
1608                  * the pcie links need some time to get going.
1609                  * 100ms works for me...
1610                  */
1611                 tb_dbg(tb, "tunnels restarted, sleeping for 100ms\n");
1612                 msleep(100);
1613         }
1614          /* Allow tb_handle_hotplug to progress events */
1615         tcm->hotplug_active = true;
1616         tb_dbg(tb, "resume finished\n");
1617
1618         return 0;
1619 }
1620
1621 static int tb_free_unplugged_xdomains(struct tb_switch *sw)
1622 {
1623         struct tb_port *port;
1624         int ret = 0;
1625
1626         tb_switch_for_each_port(sw, port) {
1627                 if (tb_is_upstream_port(port))
1628                         continue;
1629                 if (port->xdomain && port->xdomain->is_unplugged) {
1630                         tb_retimer_remove_all(port);
1631                         tb_xdomain_remove(port->xdomain);
1632                         tb_port_unconfigure_xdomain(port);
1633                         port->xdomain = NULL;
1634                         ret++;
1635                 } else if (port->remote) {
1636                         ret += tb_free_unplugged_xdomains(port->remote->sw);
1637                 }
1638         }
1639
1640         return ret;
1641 }
1642
1643 static int tb_freeze_noirq(struct tb *tb)
1644 {
1645         struct tb_cm *tcm = tb_priv(tb);
1646
1647         tcm->hotplug_active = false;
1648         return 0;
1649 }
1650
1651 static int tb_thaw_noirq(struct tb *tb)
1652 {
1653         struct tb_cm *tcm = tb_priv(tb);
1654
1655         tcm->hotplug_active = true;
1656         return 0;
1657 }
1658
1659 static void tb_complete(struct tb *tb)
1660 {
1661         /*
1662          * Release any unplugged XDomains and if there is a case where
1663          * another domain is swapped in place of unplugged XDomain we
1664          * need to run another rescan.
1665          */
1666         mutex_lock(&tb->lock);
1667         if (tb_free_unplugged_xdomains(tb->root_switch))
1668                 tb_scan_switch(tb->root_switch);
1669         mutex_unlock(&tb->lock);
1670 }
1671
1672 static int tb_runtime_suspend(struct tb *tb)
1673 {
1674         struct tb_cm *tcm = tb_priv(tb);
1675
1676         mutex_lock(&tb->lock);
1677         tb_switch_suspend(tb->root_switch, true);
1678         tcm->hotplug_active = false;
1679         mutex_unlock(&tb->lock);
1680
1681         return 0;
1682 }
1683
1684 static void tb_remove_work(struct work_struct *work)
1685 {
1686         struct tb_cm *tcm = container_of(work, struct tb_cm, remove_work.work);
1687         struct tb *tb = tcm_to_tb(tcm);
1688
1689         mutex_lock(&tb->lock);
1690         if (tb->root_switch) {
1691                 tb_free_unplugged_children(tb->root_switch);
1692                 tb_free_unplugged_xdomains(tb->root_switch);
1693         }
1694         mutex_unlock(&tb->lock);
1695 }
1696
1697 static int tb_runtime_resume(struct tb *tb)
1698 {
1699         struct tb_cm *tcm = tb_priv(tb);
1700         struct tb_tunnel *tunnel, *n;
1701
1702         mutex_lock(&tb->lock);
1703         tb_switch_resume(tb->root_switch);
1704         tb_free_invalid_tunnels(tb);
1705         tb_restore_children(tb->root_switch);
1706         list_for_each_entry_safe(tunnel, n, &tcm->tunnel_list, list)
1707                 tb_tunnel_restart(tunnel);
1708         tcm->hotplug_active = true;
1709         mutex_unlock(&tb->lock);
1710
1711         /*
1712          * Schedule cleanup of any unplugged devices. Run this in a
1713          * separate thread to avoid possible deadlock if the device
1714          * removal runtime resumes the unplugged device.
1715          */
1716         queue_delayed_work(tb->wq, &tcm->remove_work, msecs_to_jiffies(50));
1717         return 0;
1718 }
1719
1720 static const struct tb_cm_ops tb_cm_ops = {
1721         .start = tb_start,
1722         .stop = tb_stop,
1723         .suspend_noirq = tb_suspend_noirq,
1724         .resume_noirq = tb_resume_noirq,
1725         .freeze_noirq = tb_freeze_noirq,
1726         .thaw_noirq = tb_thaw_noirq,
1727         .complete = tb_complete,
1728         .runtime_suspend = tb_runtime_suspend,
1729         .runtime_resume = tb_runtime_resume,
1730         .handle_event = tb_handle_event,
1731         .disapprove_switch = tb_disconnect_pci,
1732         .approve_switch = tb_tunnel_pci,
1733         .approve_xdomain_paths = tb_approve_xdomain_paths,
1734         .disconnect_xdomain_paths = tb_disconnect_xdomain_paths,
1735 };
1736
1737 /*
1738  * During suspend the Thunderbolt controller is reset and all PCIe
1739  * tunnels are lost. The NHI driver will try to reestablish all tunnels
1740  * during resume. This adds device links between the tunneled PCIe
1741  * downstream ports and the NHI so that the device core will make sure
1742  * NHI is resumed first before the rest.
1743  */
1744 static void tb_apple_add_links(struct tb_nhi *nhi)
1745 {
1746         struct pci_dev *upstream, *pdev;
1747
1748         if (!x86_apple_machine)
1749                 return;
1750
1751         switch (nhi->pdev->device) {
1752         case PCI_DEVICE_ID_INTEL_LIGHT_RIDGE:
1753         case PCI_DEVICE_ID_INTEL_CACTUS_RIDGE_4C:
1754         case PCI_DEVICE_ID_INTEL_FALCON_RIDGE_2C_NHI:
1755         case PCI_DEVICE_ID_INTEL_FALCON_RIDGE_4C_NHI:
1756                 break;
1757         default:
1758                 return;
1759         }
1760
1761         upstream = pci_upstream_bridge(nhi->pdev);
1762         while (upstream) {
1763                 if (!pci_is_pcie(upstream))
1764                         return;
1765                 if (pci_pcie_type(upstream) == PCI_EXP_TYPE_UPSTREAM)
1766                         break;
1767                 upstream = pci_upstream_bridge(upstream);
1768         }
1769
1770         if (!upstream)
1771                 return;
1772
1773         /*
1774          * For each hotplug downstream port, create add device link
1775          * back to NHI so that PCIe tunnels can be re-established after
1776          * sleep.
1777          */
1778         for_each_pci_bridge(pdev, upstream->subordinate) {
1779                 const struct device_link *link;
1780
1781                 if (!pci_is_pcie(pdev))
1782                         continue;
1783                 if (pci_pcie_type(pdev) != PCI_EXP_TYPE_DOWNSTREAM ||
1784                     !pdev->is_hotplug_bridge)
1785                         continue;
1786
1787                 link = device_link_add(&pdev->dev, &nhi->pdev->dev,
1788                                        DL_FLAG_AUTOREMOVE_SUPPLIER |
1789                                        DL_FLAG_PM_RUNTIME);
1790                 if (link) {
1791                         dev_dbg(&nhi->pdev->dev, "created link from %s\n",
1792                                 dev_name(&pdev->dev));
1793                 } else {
1794                         dev_warn(&nhi->pdev->dev, "device link creation from %s failed\n",
1795                                  dev_name(&pdev->dev));
1796                 }
1797         }
1798 }
1799
1800 struct tb *tb_probe(struct tb_nhi *nhi)
1801 {
1802         struct tb_cm *tcm;
1803         struct tb *tb;
1804
1805         tb = tb_domain_alloc(nhi, TB_TIMEOUT, sizeof(*tcm));
1806         if (!tb)
1807                 return NULL;
1808
1809         if (tb_acpi_may_tunnel_pcie())
1810                 tb->security_level = TB_SECURITY_USER;
1811         else
1812                 tb->security_level = TB_SECURITY_NOPCIE;
1813
1814         tb->cm_ops = &tb_cm_ops;
1815
1816         tcm = tb_priv(tb);
1817         INIT_LIST_HEAD(&tcm->tunnel_list);
1818         INIT_LIST_HEAD(&tcm->dp_resources);
1819         INIT_DELAYED_WORK(&tcm->remove_work, tb_remove_work);
1820
1821         tb_dbg(tb, "using software connection manager\n");
1822
1823         tb_apple_add_links(nhi);
1824         tb_acpi_add_links(nhi);
1825
1826         return tb;
1827 }