drivers/thunderbolt/tunnel.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Thunderbolt driver - Tunneling support
   4  *
   5  * Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com>
   6  * Copyright (C) 2019, Intel Corporation
   7  */
   8
   9 #include <linux/delay.h>
  10 #include <linux/slab.h>
  11 #include <linux/list.h>
  12
  13 #include "tunnel.h"
  14 #include "tb.h"
  15
  16 /* PCIe adapters use always HopID of 8 for both directions */
  17 #define TB_PCI_HOPID                    8
  18
  19 #define TB_PCI_PATH_DOWN                0
  20 #define TB_PCI_PATH_UP                  1
  21
  22 /* USB3 adapters use always HopID of 8 for both directions */
  23 #define TB_USB3_HOPID                   8
  24
  25 #define TB_USB3_PATH_DOWN               0
  26 #define TB_USB3_PATH_UP                 1
  27
  28 /* DP adapters use HopID 8 for AUX and 9 for Video */
  29 #define TB_DP_AUX_TX_HOPID              8
  30 #define TB_DP_AUX_RX_HOPID              8
  31 #define TB_DP_VIDEO_HOPID               9
  32
  33 #define TB_DP_VIDEO_PATH_OUT            0
  34 #define TB_DP_AUX_PATH_OUT              1
  35 #define TB_DP_AUX_PATH_IN               2
  36
  37 #define TB_DMA_PATH_OUT                 0
  38 #define TB_DMA_PATH_IN                  1
  39
  40 static const char * const tb_tunnel_names[] = { "PCI", "DP", "DMA", "USB3" };
  41
  42 #define __TB_TUNNEL_PRINT(level, tunnel, fmt, arg...)                   \
  43         do {                                                            \
  44                 struct tb_tunnel *__tunnel = (tunnel);                  \
  45                 level(__tunnel->tb, "%llx:%x <-> %llx:%x (%s): " fmt,   \
  46                       tb_route(__tunnel->src_port->sw),                 \
  47                       __tunnel->src_port->port,                         \
  48                       tb_route(__tunnel->dst_port->sw),                 \
  49                       __tunnel->dst_port->port,                         \
  50                       tb_tunnel_names[__tunnel->type],                  \
  51                       ## arg);                                          \
  52         } while (0)
  53
  54 #define tb_tunnel_WARN(tunnel, fmt, arg...) \
  55         __TB_TUNNEL_PRINT(tb_WARN, tunnel, fmt, ##arg)
  56 #define tb_tunnel_warn(tunnel, fmt, arg...) \
  57         __TB_TUNNEL_PRINT(tb_warn, tunnel, fmt, ##arg)
  58 #define tb_tunnel_info(tunnel, fmt, arg...) \
  59         __TB_TUNNEL_PRINT(tb_info, tunnel, fmt, ##arg)
  60 #define tb_tunnel_dbg(tunnel, fmt, arg...) \
  61         __TB_TUNNEL_PRINT(tb_dbg, tunnel, fmt, ##arg)
  62
  63 static struct tb_tunnel *tb_tunnel_alloc(struct tb *tb, size_t npaths,
  64                                          enum tb_tunnel_type type)
  65 {
  66         struct tb_tunnel *tunnel;
  67
  68         tunnel = kzalloc(sizeof(*tunnel), GFP_KERNEL);
  69         if (!tunnel)
  70                 return NULL;
  71
  72         tunnel->paths = kcalloc(npaths, sizeof(tunnel->paths[0]), GFP_KERNEL);
  73         if (!tunnel->paths) {
  74                 tb_tunnel_free(tunnel);
  75                 return NULL;
  76         }
  77
  78         INIT_LIST_HEAD(&tunnel->list);
  79         tunnel->tb = tb;
  80         tunnel->npaths = npaths;
  81         tunnel->type = type;
  82
  83         return tunnel;
  84 }
  85
  86 static int tb_pci_activate(struct tb_tunnel *tunnel, bool activate)
  87 {
  88         int res;
  89
  90         res = tb_pci_port_enable(tunnel->src_port, activate);
  91         if (res)
  92                 return res;
  93
  94         if (tb_port_is_pcie_up(tunnel->dst_port))
  95                 return tb_pci_port_enable(tunnel->dst_port, activate);
  96
  97         return 0;
  98 }
  99
 100 static int tb_initial_credits(const struct tb_switch *sw)
 101 {
 102         /* If the path is complete sw is not NULL */
 103         if (sw) {
 104                 /* More credits for faster link */
 105                 switch (sw->link_speed * sw->link_width) {
 106                 case 40:
 107                         return 32;
 108                 case 20:
 109                         return 24;
 110                 }
 111         }
 112
 113         return 16;
 114 }
 115
 116 static void tb_pci_init_path(struct tb_path *path)
 117 {
 118         path->egress_fc_enable = TB_PATH_SOURCE | TB_PATH_INTERNAL;
 119         path->egress_shared_buffer = TB_PATH_NONE;
 120         path->ingress_fc_enable = TB_PATH_ALL;
 121         path->ingress_shared_buffer = TB_PATH_NONE;
 122         path->priority = 3;
 123         path->weight = 1;
 124         path->drop_packages = 0;
 125         path->nfc_credits = 0;
 126         path->hops[0].initial_credits = 7;
 127         if (path->path_length > 1)
 128                 path->hops[1].initial_credits =
 129                         tb_initial_credits(path->hops[1].in_port->sw);
 130 }
 131
 132 /**
 133  * tb_tunnel_discover_pci() - Discover existing PCIe tunnels
 134  * @tb: Pointer to the domain structure
 135  * @down: PCIe downstream adapter
 136  *
 137  * If @down adapter is active, follows the tunnel to the PCIe upstream
 138  * adapter and back. Returns the discovered tunnel or %NULL if there was
 139  * no tunnel.
 140  */
 141 struct tb_tunnel *tb_tunnel_discover_pci(struct tb *tb, struct tb_port *down)
 142 {
 143         struct tb_tunnel *tunnel;
 144         struct tb_path *path;
 145
 146         if (!tb_pci_port_is_enabled(down))
 147                 return NULL;
 148
 149         tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_PCI);
 150         if (!tunnel)
 151                 return NULL;
 152
 153         tunnel->activate = tb_pci_activate;
 154         tunnel->src_port = down;
 155
 156         /*
 157          * Discover both paths even if they are not complete. We will
 158          * clean them up by calling tb_tunnel_deactivate() below in that
 159          * case.
 160          */
 161         path = tb_path_discover(down, TB_PCI_HOPID, NULL, -1,
 162                                 &tunnel->dst_port, "PCIe Up");
 163         if (!path) {
 164                 /* Just disable the downstream port */
 165                 tb_pci_port_enable(down, false);
 166                 goto err_free;
 167         }
 168         tunnel->paths[TB_PCI_PATH_UP] = path;
 169         tb_pci_init_path(tunnel->paths[TB_PCI_PATH_UP]);
 170
 171         path = tb_path_discover(tunnel->dst_port, -1, down, TB_PCI_HOPID, NULL,
 172                                 "PCIe Down");
 173         if (!path)
 174                 goto err_deactivate;
 175         tunnel->paths[TB_PCI_PATH_DOWN] = path;
 176         tb_pci_init_path(tunnel->paths[TB_PCI_PATH_DOWN]);
 177
 178         /* Validate that the tunnel is complete */
 179         if (!tb_port_is_pcie_up(tunnel->dst_port)) {
 180                 tb_port_warn(tunnel->dst_port,
 181                              "path does not end on a PCIe adapter, cleaning up\n");
 182                 goto err_deactivate;
 183         }
 184
 185         if (down != tunnel->src_port) {
 186                 tb_tunnel_warn(tunnel, "path is not complete, cleaning up\n");
 187                 goto err_deactivate;
 188         }
 189
 190         if (!tb_pci_port_is_enabled(tunnel->dst_port)) {
 191                 tb_tunnel_warn(tunnel,
 192                                "tunnel is not fully activated, cleaning up\n");
 193                 goto err_deactivate;
 194         }
 195
 196         tb_tunnel_dbg(tunnel, "discovered\n");
 197         return tunnel;
 198
 199 err_deactivate:
 200         tb_tunnel_deactivate(tunnel);
 201 err_free:
 202         tb_tunnel_free(tunnel);
 203
 204         return NULL;
 205 }
 206
 207 /**
 208  * tb_tunnel_alloc_pci() - allocate a pci tunnel
 209  * @tb: Pointer to the domain structure
 210  * @up: PCIe upstream adapter port
 211  * @down: PCIe downstream adapter port
 212  *
 213  * Allocate a PCI tunnel. The ports must be of type TB_TYPE_PCIE_UP and
 214  * TB_TYPE_PCIE_DOWN.
 215  *
 216  * Return: Returns a tb_tunnel on success or NULL on failure.
 217  */
 218 struct tb_tunnel *tb_tunnel_alloc_pci(struct tb *tb, struct tb_port *up,
 219                                       struct tb_port *down)
 220 {
 221         struct tb_tunnel *tunnel;
 222         struct tb_path *path;
 223
 224         tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_PCI);
 225         if (!tunnel)
 226                 return NULL;
 227
 228         tunnel->activate = tb_pci_activate;
 229         tunnel->src_port = down;
 230         tunnel->dst_port = up;
 231
 232         path = tb_path_alloc(tb, down, TB_PCI_HOPID, up, TB_PCI_HOPID, 0,
 233                              "PCIe Down");
 234         if (!path) {
 235                 tb_tunnel_free(tunnel);
 236                 return NULL;
 237         }
 238         tb_pci_init_path(path);
 239         tunnel->paths[TB_PCI_PATH_DOWN] = path;
 240
 241         path = tb_path_alloc(tb, up, TB_PCI_HOPID, down, TB_PCI_HOPID, 0,
 242                              "PCIe Up");
 243         if (!path) {
 244                 tb_tunnel_free(tunnel);
 245                 return NULL;
 246         }
 247         tb_pci_init_path(path);
 248         tunnel->paths[TB_PCI_PATH_UP] = path;
 249
 250         return tunnel;
 251 }
 252
 253 static bool tb_dp_is_usb4(const struct tb_switch *sw)
 254 {
 255         /* Titan Ridge DP adapters need the same treatment as USB4 */
 256         return tb_switch_is_usb4(sw) || tb_switch_is_titan_ridge(sw);
 257 }
 258
 259 static int tb_dp_cm_handshake(struct tb_port *in, struct tb_port *out)
 260 {
 261         int timeout = 10;
 262         u32 val;
 263         int ret;
 264
 265         /* Both ends need to support this */
 266         if (!tb_dp_is_usb4(in->sw) || !tb_dp_is_usb4(out->sw))
 267                 return 0;
 268
 269         ret = tb_port_read(out, &val, TB_CFG_PORT,
 270                            out->cap_adap + DP_STATUS_CTRL, 1);
 271         if (ret)
 272                 return ret;
 273
 274         val |= DP_STATUS_CTRL_UF | DP_STATUS_CTRL_CMHS;
 275
 276         ret = tb_port_write(out, &val, TB_CFG_PORT,
 277                             out->cap_adap + DP_STATUS_CTRL, 1);
 278         if (ret)
 279                 return ret;
 280
 281         do {
 282                 ret = tb_port_read(out, &val, TB_CFG_PORT,
 283                                    out->cap_adap + DP_STATUS_CTRL, 1);
 284                 if (ret)
 285                         return ret;
 286                 if (!(val & DP_STATUS_CTRL_CMHS))
 287                         return 0;
 288                 usleep_range(10, 100);
 289         } while (timeout--);
 290
 291         return -ETIMEDOUT;
 292 }
 293
 294 static inline u32 tb_dp_cap_get_rate(u32 val)
 295 {
 296         u32 rate = (val & DP_COMMON_CAP_RATE_MASK) >> DP_COMMON_CAP_RATE_SHIFT;
 297
 298         switch (rate) {
 299         case DP_COMMON_CAP_RATE_RBR:
 300                 return 1620;
 301         case DP_COMMON_CAP_RATE_HBR:
 302                 return 2700;
 303         case DP_COMMON_CAP_RATE_HBR2:
 304                 return 5400;
 305         case DP_COMMON_CAP_RATE_HBR3:
 306                 return 8100;
 307         default:
 308                 return 0;
 309         }
 310 }
 311
 312 static inline u32 tb_dp_cap_set_rate(u32 val, u32 rate)
 313 {
 314         val &= ~DP_COMMON_CAP_RATE_MASK;
 315         switch (rate) {
 316         default:
 317                 WARN(1, "invalid rate %u passed, defaulting to 1620 MB/s\n", rate);
 318                 fallthrough;
 319         case 1620:
 320                 val |= DP_COMMON_CAP_RATE_RBR << DP_COMMON_CAP_RATE_SHIFT;
 321                 break;
 322         case 2700:
 323                 val |= DP_COMMON_CAP_RATE_HBR << DP_COMMON_CAP_RATE_SHIFT;
 324                 break;
 325         case 5400:
 326                 val |= DP_COMMON_CAP_RATE_HBR2 << DP_COMMON_CAP_RATE_SHIFT;
 327                 break;
 328         case 8100:
 329                 val |= DP_COMMON_CAP_RATE_HBR3 << DP_COMMON_CAP_RATE_SHIFT;
 330                 break;
 331         }
 332         return val;
 333 }
 334
 335 static inline u32 tb_dp_cap_get_lanes(u32 val)
 336 {
 337         u32 lanes = (val & DP_COMMON_CAP_LANES_MASK) >> DP_COMMON_CAP_LANES_SHIFT;
 338
 339         switch (lanes) {
 340         case DP_COMMON_CAP_1_LANE:
 341                 return 1;
 342         case DP_COMMON_CAP_2_LANES:
 343                 return 2;
 344         case DP_COMMON_CAP_4_LANES:
 345                 return 4;
 346         default:
 347                 return 0;
 348         }
 349 }
 350
 351 static inline u32 tb_dp_cap_set_lanes(u32 val, u32 lanes)
 352 {
 353         val &= ~DP_COMMON_CAP_LANES_MASK;
 354         switch (lanes) {
 355         default:
 356                 WARN(1, "invalid number of lanes %u passed, defaulting to 1\n",
 357                      lanes);
 358                 fallthrough;
 359         case 1:
 360                 val |= DP_COMMON_CAP_1_LANE << DP_COMMON_CAP_LANES_SHIFT;
 361                 break;
 362         case 2:
 363                 val |= DP_COMMON_CAP_2_LANES << DP_COMMON_CAP_LANES_SHIFT;
 364                 break;
 365         case 4:
 366                 val |= DP_COMMON_CAP_4_LANES << DP_COMMON_CAP_LANES_SHIFT;
 367                 break;
 368         }
 369         return val;
 370 }
 371
 372 static unsigned int tb_dp_bandwidth(unsigned int rate, unsigned int lanes)
 373 {
 374         /* Tunneling removes the DP 8b/10b encoding */
 375         return rate * lanes * 8 / 10;
 376 }
 377
 378 static int tb_dp_reduce_bandwidth(int max_bw, u32 in_rate, u32 in_lanes,
 379                                   u32 out_rate, u32 out_lanes, u32 *new_rate,
 380                                   u32 *new_lanes)
 381 {
 382         static const u32 dp_bw[][2] = {
 383                 /* Mb/s, lanes */
 384                 { 8100, 4 }, /* 25920 Mb/s */
 385                 { 5400, 4 }, /* 17280 Mb/s */
 386                 { 8100, 2 }, /* 12960 Mb/s */
 387                 { 2700, 4 }, /* 8640 Mb/s */
 388                 { 5400, 2 }, /* 8640 Mb/s */
 389                 { 8100, 1 }, /* 6480 Mb/s */
 390                 { 1620, 4 }, /* 5184 Mb/s */
 391                 { 5400, 1 }, /* 4320 Mb/s */
 392                 { 2700, 2 }, /* 4320 Mb/s */
 393                 { 1620, 2 }, /* 2592 Mb/s */
 394                 { 2700, 1 }, /* 2160 Mb/s */
 395                 { 1620, 1 }, /* 1296 Mb/s */
 396         };
 397         unsigned int i;
 398
 399         /*
 400          * Find a combination that can fit into max_bw and does not
 401          * exceed the maximum rate and lanes supported by the DP OUT and
 402          * DP IN adapters.
 403          */
 404         for (i = 0; i < ARRAY_SIZE(dp_bw); i++) {
 405                 if (dp_bw[i][0] > out_rate || dp_bw[i][1] > out_lanes)
 406                         continue;
 407
 408                 if (dp_bw[i][0] > in_rate || dp_bw[i][1] > in_lanes)
 409                         continue;
 410
 411                 if (tb_dp_bandwidth(dp_bw[i][0], dp_bw[i][1]) <= max_bw) {
 412                         *new_rate = dp_bw[i][0];
 413                         *new_lanes = dp_bw[i][1];
 414                         return 0;
 415                 }
 416         }
 417
 418         return -ENOSR;
 419 }
 420
 421 static int tb_dp_xchg_caps(struct tb_tunnel *tunnel)
 422 {
 423         u32 out_dp_cap, out_rate, out_lanes, in_dp_cap, in_rate, in_lanes, bw;
 424         struct tb_port *out = tunnel->dst_port;
 425         struct tb_port *in = tunnel->src_port;
 426         int ret, max_bw;
 427
 428         /*
 429          * Copy DP_LOCAL_CAP register to DP_REMOTE_CAP register for
 430          * newer generation hardware.
 431          */
 432         if (in->sw->generation < 2 || out->sw->generation < 2)
 433                 return 0;
 434
 435         /*
 436          * Perform connection manager handshake between IN and OUT ports
 437          * before capabilities exchange can take place.
 438          */
 439         ret = tb_dp_cm_handshake(in, out);
 440         if (ret)
 441                 return ret;
 442
 443         /* Read both DP_LOCAL_CAP registers */
 444         ret = tb_port_read(in, &in_dp_cap, TB_CFG_PORT,
 445                            in->cap_adap + DP_LOCAL_CAP, 1);
 446         if (ret)
 447                 return ret;
 448
 449         ret = tb_port_read(out, &out_dp_cap, TB_CFG_PORT,
 450                            out->cap_adap + DP_LOCAL_CAP, 1);
 451         if (ret)
 452                 return ret;
 453
 454         /* Write IN local caps to OUT remote caps */
 455         ret = tb_port_write(out, &in_dp_cap, TB_CFG_PORT,
 456                             out->cap_adap + DP_REMOTE_CAP, 1);
 457         if (ret)
 458                 return ret;
 459
 460         in_rate = tb_dp_cap_get_rate(in_dp_cap);
 461         in_lanes = tb_dp_cap_get_lanes(in_dp_cap);
 462         tb_port_dbg(in, "maximum supported bandwidth %u Mb/s x%u = %u Mb/s\n",
 463                     in_rate, in_lanes, tb_dp_bandwidth(in_rate, in_lanes));
 464
 465         /*
 466          * If the tunnel bandwidth is limited (max_bw is set) then see
 467          * if we need to reduce bandwidth to fit there.
 468          */
 469         out_rate = tb_dp_cap_get_rate(out_dp_cap);
 470         out_lanes = tb_dp_cap_get_lanes(out_dp_cap);
 471         bw = tb_dp_bandwidth(out_rate, out_lanes);
 472         tb_port_dbg(out, "maximum supported bandwidth %u Mb/s x%u = %u Mb/s\n",
 473                     out_rate, out_lanes, bw);
 474
 475         if (in->sw->config.depth < out->sw->config.depth)
 476                 max_bw = tunnel->max_down;
 477         else
 478                 max_bw = tunnel->max_up;
 479
 480         if (max_bw && bw > max_bw) {
 481                 u32 new_rate, new_lanes, new_bw;
 482
 483                 ret = tb_dp_reduce_bandwidth(max_bw, in_rate, in_lanes,
 484                                              out_rate, out_lanes, &new_rate,
 485                                              &new_lanes);
 486                 if (ret) {
 487                         tb_port_info(out, "not enough bandwidth for DP tunnel\n");
 488                         return ret;
 489                 }
 490
 491                 new_bw = tb_dp_bandwidth(new_rate, new_lanes);
 492                 tb_port_dbg(out, "bandwidth reduced to %u Mb/s x%u = %u Mb/s\n",
 493                             new_rate, new_lanes, new_bw);
 494
 495                 /*
 496                  * Set new rate and number of lanes before writing it to
 497                  * the IN port remote caps.
 498                  */
 499                 out_dp_cap = tb_dp_cap_set_rate(out_dp_cap, new_rate);
 500                 out_dp_cap = tb_dp_cap_set_lanes(out_dp_cap, new_lanes);
 501         }
 502
 503         return tb_port_write(in, &out_dp_cap, TB_CFG_PORT,
 504                              in->cap_adap + DP_REMOTE_CAP, 1);
 505 }
 506
 507 static int tb_dp_activate(struct tb_tunnel *tunnel, bool active)
 508 {
 509         int ret;
 510
 511         if (active) {
 512                 struct tb_path **paths;
 513                 int last;
 514
 515                 paths = tunnel->paths;
 516                 last = paths[TB_DP_VIDEO_PATH_OUT]->path_length - 1;
 517
 518                 tb_dp_port_set_hops(tunnel->src_port,
 519                         paths[TB_DP_VIDEO_PATH_OUT]->hops[0].in_hop_index,
 520                         paths[TB_DP_AUX_PATH_OUT]->hops[0].in_hop_index,
 521                         paths[TB_DP_AUX_PATH_IN]->hops[last].next_hop_index);
 522
 523                 tb_dp_port_set_hops(tunnel->dst_port,
 524                         paths[TB_DP_VIDEO_PATH_OUT]->hops[last].next_hop_index,
 525                         paths[TB_DP_AUX_PATH_IN]->hops[0].in_hop_index,
 526                         paths[TB_DP_AUX_PATH_OUT]->hops[last].next_hop_index);
 527         } else {
 528                 tb_dp_port_hpd_clear(tunnel->src_port);
 529                 tb_dp_port_set_hops(tunnel->src_port, 0, 0, 0);
 530                 if (tb_port_is_dpout(tunnel->dst_port))
 531                         tb_dp_port_set_hops(tunnel->dst_port, 0, 0, 0);
 532         }
 533
 534         ret = tb_dp_port_enable(tunnel->src_port, active);
 535         if (ret)
 536                 return ret;
 537
 538         if (tb_port_is_dpout(tunnel->dst_port))
 539                 return tb_dp_port_enable(tunnel->dst_port, active);
 540
 541         return 0;
 542 }
 543
 544 static int tb_dp_consumed_bandwidth(struct tb_tunnel *tunnel, int *consumed_up,
 545                                     int *consumed_down)
 546 {
 547         struct tb_port *in = tunnel->src_port;
 548         const struct tb_switch *sw = in->sw;
 549         u32 val, rate = 0, lanes = 0;
 550         int ret;
 551
 552         if (tb_dp_is_usb4(sw)) {
 553                 int timeout = 20;
 554
 555                 /*
 556                  * Wait for DPRX done. Normally it should be already set
 557                  * for active tunnel.
 558                  */
 559                 do {
 560                         ret = tb_port_read(in, &val, TB_CFG_PORT,
 561                                            in->cap_adap + DP_COMMON_CAP, 1);
 562                         if (ret)
 563                                 return ret;
 564
 565                         if (val & DP_COMMON_CAP_DPRX_DONE) {
 566                                 rate = tb_dp_cap_get_rate(val);
 567                                 lanes = tb_dp_cap_get_lanes(val);
 568                                 break;
 569                         }
 570                         msleep(250);
 571                 } while (timeout--);
 572
 573                 if (!timeout)
 574                         return -ETIMEDOUT;
 575         } else if (sw->generation >= 2) {
 576                 /*
 577                  * Read from the copied remote cap so that we take into
 578                  * account if capabilities were reduced during exchange.
 579                  */
 580                 ret = tb_port_read(in, &val, TB_CFG_PORT,
 581                                    in->cap_adap + DP_REMOTE_CAP, 1);
 582                 if (ret)
 583                         return ret;
 584
 585                 rate = tb_dp_cap_get_rate(val);
 586                 lanes = tb_dp_cap_get_lanes(val);
 587         } else {
 588                 /* No bandwidth management for legacy devices  */
 589                 *consumed_up = 0;
 590                 *consumed_down = 0;
 591                 return 0;
 592         }
 593
 594         if (in->sw->config.depth < tunnel->dst_port->sw->config.depth) {
 595                 *consumed_up = 0;
 596                 *consumed_down = tb_dp_bandwidth(rate, lanes);
 597         } else {
 598                 *consumed_up = tb_dp_bandwidth(rate, lanes);
 599                 *consumed_down = 0;
 600         }
 601
 602         return 0;
 603 }
 604
 605 static void tb_dp_init_aux_path(struct tb_path *path)
 606 {
 607         int i;
 608
 609         path->egress_fc_enable = TB_PATH_SOURCE | TB_PATH_INTERNAL;
 610         path->egress_shared_buffer = TB_PATH_NONE;
 611         path->ingress_fc_enable = TB_PATH_ALL;
 612         path->ingress_shared_buffer = TB_PATH_NONE;
 613         path->priority = 2;
 614         path->weight = 1;
 615
 616         for (i = 0; i < path->path_length; i++)
 617                 path->hops[i].initial_credits = 1;
 618 }
 619
 620 static void tb_dp_init_video_path(struct tb_path *path, bool discover)
 621 {
 622         u32 nfc_credits = path->hops[0].in_port->config.nfc_credits;
 623
 624         path->egress_fc_enable = TB_PATH_NONE;
 625         path->egress_shared_buffer = TB_PATH_NONE;
 626         path->ingress_fc_enable = TB_PATH_NONE;
 627         path->ingress_shared_buffer = TB_PATH_NONE;
 628         path->priority = 1;
 629         path->weight = 1;
 630
 631         if (discover) {
 632                 path->nfc_credits = nfc_credits & ADP_CS_4_NFC_BUFFERS_MASK;
 633         } else {
 634                 u32 max_credits;
 635
 636                 max_credits = (nfc_credits & ADP_CS_4_TOTAL_BUFFERS_MASK) >>
 637                         ADP_CS_4_TOTAL_BUFFERS_SHIFT;
 638                 /* Leave some credits for AUX path */
 639                 path->nfc_credits = min(max_credits - 2, 12U);
 640         }
 641 }
 642
 643 /**
 644  * tb_tunnel_discover_dp() - Discover existing Display Port tunnels
 645  * @tb: Pointer to the domain structure
 646  * @in: DP in adapter
 647  *
 648  * If @in adapter is active, follows the tunnel to the DP out adapter
 649  * and back. Returns the discovered tunnel or %NULL if there was no
 650  * tunnel.
 651  *
 652  * Return: DP tunnel or %NULL if no tunnel found.
 653  */
 654 struct tb_tunnel *tb_tunnel_discover_dp(struct tb *tb, struct tb_port *in)
 655 {
 656         struct tb_tunnel *tunnel;
 657         struct tb_port *port;
 658         struct tb_path *path;
 659
 660         if (!tb_dp_port_is_enabled(in))
 661                 return NULL;
 662
 663         tunnel = tb_tunnel_alloc(tb, 3, TB_TUNNEL_DP);
 664         if (!tunnel)
 665                 return NULL;
 666
 667         tunnel->init = tb_dp_xchg_caps;
 668         tunnel->activate = tb_dp_activate;
 669         tunnel->consumed_bandwidth = tb_dp_consumed_bandwidth;
 670         tunnel->src_port = in;
 671
 672         path = tb_path_discover(in, TB_DP_VIDEO_HOPID, NULL, -1,
 673                                 &tunnel->dst_port, "Video");
 674         if (!path) {
 675                 /* Just disable the DP IN port */
 676                 tb_dp_port_enable(in, false);
 677                 goto err_free;
 678         }
 679         tunnel->paths[TB_DP_VIDEO_PATH_OUT] = path;
 680         tb_dp_init_video_path(tunnel->paths[TB_DP_VIDEO_PATH_OUT], true);
 681
 682         path = tb_path_discover(in, TB_DP_AUX_TX_HOPID, NULL, -1, NULL, "AUX TX");
 683         if (!path)
 684                 goto err_deactivate;
 685         tunnel->paths[TB_DP_AUX_PATH_OUT] = path;
 686         tb_dp_init_aux_path(tunnel->paths[TB_DP_AUX_PATH_OUT]);
 687
 688         path = tb_path_discover(tunnel->dst_port, -1, in, TB_DP_AUX_RX_HOPID,
 689                                 &port, "AUX RX");
 690         if (!path)
 691                 goto err_deactivate;
 692         tunnel->paths[TB_DP_AUX_PATH_IN] = path;
 693         tb_dp_init_aux_path(tunnel->paths[TB_DP_AUX_PATH_IN]);
 694
 695         /* Validate that the tunnel is complete */
 696         if (!tb_port_is_dpout(tunnel->dst_port)) {
 697                 tb_port_warn(in, "path does not end on a DP adapter, cleaning up\n");
 698                 goto err_deactivate;
 699         }
 700
 701         if (!tb_dp_port_is_enabled(tunnel->dst_port))
 702                 goto err_deactivate;
 703
 704         if (!tb_dp_port_hpd_is_active(tunnel->dst_port))
 705                 goto err_deactivate;
 706
 707         if (port != tunnel->src_port) {
 708                 tb_tunnel_warn(tunnel, "path is not complete, cleaning up\n");
 709                 goto err_deactivate;
 710         }
 711
 712         tb_tunnel_dbg(tunnel, "discovered\n");
 713         return tunnel;
 714
 715 err_deactivate:
 716         tb_tunnel_deactivate(tunnel);
 717 err_free:
 718         tb_tunnel_free(tunnel);
 719
 720         return NULL;
 721 }
 722
 723 /**
 724  * tb_tunnel_alloc_dp() - allocate a Display Port tunnel
 725  * @tb: Pointer to the domain structure
 726  * @in: DP in adapter port
 727  * @out: DP out adapter port
 728  * @max_up: Maximum available upstream bandwidth for the DP tunnel (%0
 729  *          if not limited)
 730  * @max_down: Maximum available downstream bandwidth for the DP tunnel
 731  *            (%0 if not limited)
 732  *
 733  * Allocates a tunnel between @in and @out that is capable of tunneling
 734  * Display Port traffic.
 735  *
 736  * Return: Returns a tb_tunnel on success or NULL on failure.
 737  */
 738 struct tb_tunnel *tb_tunnel_alloc_dp(struct tb *tb, struct tb_port *in,
 739                                      struct tb_port *out, int max_up,
 740                                      int max_down)
 741 {
 742         struct tb_tunnel *tunnel;
 743         struct tb_path **paths;
 744         struct tb_path *path;
 745
 746         if (WARN_ON(!in->cap_adap || !out->cap_adap))
 747                 return NULL;
 748
 749         tunnel = tb_tunnel_alloc(tb, 3, TB_TUNNEL_DP);
 750         if (!tunnel)
 751                 return NULL;
 752
 753         tunnel->init = tb_dp_xchg_caps;
 754         tunnel->activate = tb_dp_activate;
 755         tunnel->consumed_bandwidth = tb_dp_consumed_bandwidth;
 756         tunnel->src_port = in;
 757         tunnel->dst_port = out;
 758         tunnel->max_up = max_up;
 759         tunnel->max_down = max_down;
 760
 761         paths = tunnel->paths;
 762
 763         path = tb_path_alloc(tb, in, TB_DP_VIDEO_HOPID, out, TB_DP_VIDEO_HOPID,
 764                              1, "Video");
 765         if (!path)
 766                 goto err_free;
 767         tb_dp_init_video_path(path, false);
 768         paths[TB_DP_VIDEO_PATH_OUT] = path;
 769
 770         path = tb_path_alloc(tb, in, TB_DP_AUX_TX_HOPID, out,
 771                              TB_DP_AUX_TX_HOPID, 1, "AUX TX");
 772         if (!path)
 773                 goto err_free;
 774         tb_dp_init_aux_path(path);
 775         paths[TB_DP_AUX_PATH_OUT] = path;
 776
 777         path = tb_path_alloc(tb, out, TB_DP_AUX_RX_HOPID, in,
 778                              TB_DP_AUX_RX_HOPID, 1, "AUX RX");
 779         if (!path)
 780                 goto err_free;
 781         tb_dp_init_aux_path(path);
 782         paths[TB_DP_AUX_PATH_IN] = path;
 783
 784         return tunnel;
 785
 786 err_free:
 787         tb_tunnel_free(tunnel);
 788         return NULL;
 789 }
 790
 791 static u32 tb_dma_credits(struct tb_port *nhi)
 792 {
 793         u32 max_credits;
 794
 795         max_credits = (nhi->config.nfc_credits & ADP_CS_4_TOTAL_BUFFERS_MASK) >>
 796                 ADP_CS_4_TOTAL_BUFFERS_SHIFT;
 797         return min(max_credits, 13U);
 798 }
 799
 800 static int tb_dma_activate(struct tb_tunnel *tunnel, bool active)
 801 {
 802         struct tb_port *nhi = tunnel->src_port;
 803         u32 credits;
 804
 805         credits = active ? tb_dma_credits(nhi) : 0;
 806         return tb_port_set_initial_credits(nhi, credits);
 807 }
 808
 809 static void tb_dma_init_path(struct tb_path *path, unsigned int isb,
 810                              unsigned int efc, u32 credits)
 811 {
 812         int i;
 813
 814         path->egress_fc_enable = efc;
 815         path->ingress_fc_enable = TB_PATH_ALL;
 816         path->egress_shared_buffer = TB_PATH_NONE;
 817         path->ingress_shared_buffer = isb;
 818         path->priority = 5;
 819         path->weight = 1;
 820         path->clear_fc = true;
 821
 822         for (i = 0; i < path->path_length; i++)
 823                 path->hops[i].initial_credits = credits;
 824 }
 825
 826 /**
 827  * tb_tunnel_alloc_dma() - allocate a DMA tunnel
 828  * @tb: Pointer to the domain structure
 829  * @nhi: Host controller port
 830  * @dst: Destination null port which the other domain is connected to
 831  * @transmit_ring: NHI ring number used to send packets towards the
 832  *                 other domain
 833  * @transmit_path: HopID used for transmitting packets
 834  * @receive_ring: NHI ring number used to receive packets from the
 835  *                other domain
 836  * @reveive_path: HopID used for receiving packets
 837  *
 838  * Return: Returns a tb_tunnel on success or NULL on failure.
 839  */
 840 struct tb_tunnel *tb_tunnel_alloc_dma(struct tb *tb, struct tb_port *nhi,
 841                                       struct tb_port *dst, int transmit_ring,
 842                                       int transmit_path, int receive_ring,
 843                                       int receive_path)
 844 {
 845         struct tb_tunnel *tunnel;
 846         struct tb_path *path;
 847         u32 credits;
 848
 849         tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_DMA);
 850         if (!tunnel)
 851                 return NULL;
 852
 853         tunnel->activate = tb_dma_activate;
 854         tunnel->src_port = nhi;
 855         tunnel->dst_port = dst;
 856
 857         credits = tb_dma_credits(nhi);
 858
 859         path = tb_path_alloc(tb, dst, receive_path, nhi, receive_ring, 0, "DMA RX");
 860         if (!path) {
 861                 tb_tunnel_free(tunnel);
 862                 return NULL;
 863         }
 864         tb_dma_init_path(path, TB_PATH_NONE, TB_PATH_SOURCE | TB_PATH_INTERNAL,
 865                          credits);
 866         tunnel->paths[TB_DMA_PATH_IN] = path;
 867
 868         path = tb_path_alloc(tb, nhi, transmit_ring, dst, transmit_path, 0, "DMA TX");
 869         if (!path) {
 870                 tb_tunnel_free(tunnel);
 871                 return NULL;
 872         }
 873         tb_dma_init_path(path, TB_PATH_SOURCE, TB_PATH_ALL, credits);
 874         tunnel->paths[TB_DMA_PATH_OUT] = path;
 875
 876         return tunnel;
 877 }
 878
 879 static int tb_usb3_max_link_rate(struct tb_port *up, struct tb_port *down)
 880 {
 881         int ret, up_max_rate, down_max_rate;
 882
 883         ret = usb4_usb3_port_max_link_rate(up);
 884         if (ret < 0)
 885                 return ret;
 886         up_max_rate = ret;
 887
 888         ret = usb4_usb3_port_max_link_rate(down);
 889         if (ret < 0)
 890                 return ret;
 891         down_max_rate = ret;
 892
 893         return min(up_max_rate, down_max_rate);
 894 }
 895
 896 static int tb_usb3_init(struct tb_tunnel *tunnel)
 897 {
 898         tb_tunnel_dbg(tunnel, "allocating initial bandwidth %d/%d Mb/s\n",
 899                       tunnel->allocated_up, tunnel->allocated_down);
 900
 901         return usb4_usb3_port_allocate_bandwidth(tunnel->src_port,
 902                                                  &tunnel->allocated_up,
 903                                                  &tunnel->allocated_down);
 904 }
 905
 906 static int tb_usb3_activate(struct tb_tunnel *tunnel, bool activate)
 907 {
 908         int res;
 909
 910         res = tb_usb3_port_enable(tunnel->src_port, activate);
 911         if (res)
 912                 return res;
 913
 914         if (tb_port_is_usb3_up(tunnel->dst_port))
 915                 return tb_usb3_port_enable(tunnel->dst_port, activate);
 916
 917         return 0;
 918 }
 919
 920 static int tb_usb3_consumed_bandwidth(struct tb_tunnel *tunnel,
 921                 int *consumed_up, int *consumed_down)
 922 {
 923         /*
 924          * PCIe tunneling affects the USB3 bandwidth so take that it
 925          * into account here.
 926          */
 927         *consumed_up = tunnel->allocated_up * (3 + 1) / 3;
 928         *consumed_down = tunnel->allocated_down * (3 + 1) / 3;
 929         return 0;
 930 }
 931
 932 static int tb_usb3_release_unused_bandwidth(struct tb_tunnel *tunnel)
 933 {
 934         int ret;
 935
 936         ret = usb4_usb3_port_release_bandwidth(tunnel->src_port,
 937                                                &tunnel->allocated_up,
 938                                                &tunnel->allocated_down);
 939         if (ret)
 940                 return ret;
 941
 942         tb_tunnel_dbg(tunnel, "decreased bandwidth allocation to %d/%d Mb/s\n",
 943                       tunnel->allocated_up, tunnel->allocated_down);
 944         return 0;
 945 }
 946
 947 static void tb_usb3_reclaim_available_bandwidth(struct tb_tunnel *tunnel,
 948                                                 int *available_up,
 949                                                 int *available_down)
 950 {
 951         int ret, max_rate, allocate_up, allocate_down;
 952
 953         ret = usb4_usb3_port_actual_link_rate(tunnel->src_port);
 954         if (ret < 0) {
 955                 tb_tunnel_warn(tunnel, "failed to read actual link rate\n");
 956                 return;
 957         } else if (!ret) {
 958                 /* Use maximum link rate if the link valid is not set */
 959                 ret = usb4_usb3_port_max_link_rate(tunnel->src_port);
 960                 if (ret < 0) {
 961                         tb_tunnel_warn(tunnel, "failed to read maximum link rate\n");
 962                         return;
 963                 }
 964         }
 965
 966         /*
 967          * 90% of the max rate can be allocated for isochronous
 968          * transfers.
 969          */
 970         max_rate = ret * 90 / 100;
 971
 972         /* No need to reclaim if already at maximum */
 973         if (tunnel->allocated_up >= max_rate &&
 974             tunnel->allocated_down >= max_rate)
 975                 return;
 976
 977         /* Don't go lower than what is already allocated */
 978         allocate_up = min(max_rate, *available_up);
 979         if (allocate_up < tunnel->allocated_up)
 980                 allocate_up = tunnel->allocated_up;
 981
 982         allocate_down = min(max_rate, *available_down);
 983         if (allocate_down < tunnel->allocated_down)
 984                 allocate_down = tunnel->allocated_down;
 985
 986         /* If no changes no need to do more */
 987         if (allocate_up == tunnel->allocated_up &&
 988             allocate_down == tunnel->allocated_down)
 989                 return;
 990
 991         ret = usb4_usb3_port_allocate_bandwidth(tunnel->src_port, &allocate_up,
 992                                                 &allocate_down);
 993         if (ret) {
 994                 tb_tunnel_info(tunnel, "failed to allocate bandwidth\n");
 995                 return;
 996         }
 997
 998         tunnel->allocated_up = allocate_up;
 999         *available_up -= tunnel->allocated_up;
1000
1001         tunnel->allocated_down = allocate_down;
1002         *available_down -= tunnel->allocated_down;
1003
1004         tb_tunnel_dbg(tunnel, "increased bandwidth allocation to %d/%d Mb/s\n",
1005                       tunnel->allocated_up, tunnel->allocated_down);
1006 }
1007
1008 static void tb_usb3_init_path(struct tb_path *path)
1009 {
1010         path->egress_fc_enable = TB_PATH_SOURCE | TB_PATH_INTERNAL;
1011         path->egress_shared_buffer = TB_PATH_NONE;
1012         path->ingress_fc_enable = TB_PATH_ALL;
1013         path->ingress_shared_buffer = TB_PATH_NONE;
1014         path->priority = 3;
1015         path->weight = 3;
1016         path->drop_packages = 0;
1017         path->nfc_credits = 0;
1018         path->hops[0].initial_credits = 7;
1019         if (path->path_length > 1)
1020                 path->hops[1].initial_credits =
1021                         tb_initial_credits(path->hops[1].in_port->sw);
1022 }
1023
1024 /**
1025  * tb_tunnel_discover_usb3() - Discover existing USB3 tunnels
1026  * @tb: Pointer to the domain structure
1027  * @down: USB3 downstream adapter
1028  *
1029  * If @down adapter is active, follows the tunnel to the USB3 upstream
1030  * adapter and back. Returns the discovered tunnel or %NULL if there was
1031  * no tunnel.
1032  */
1033 struct tb_tunnel *tb_tunnel_discover_usb3(struct tb *tb, struct tb_port *down)
1034 {
1035         struct tb_tunnel *tunnel;
1036         struct tb_path *path;
1037
1038         if (!tb_usb3_port_is_enabled(down))
1039                 return NULL;
1040
1041         tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_USB3);
1042         if (!tunnel)
1043                 return NULL;
1044
1045         tunnel->activate = tb_usb3_activate;
1046         tunnel->src_port = down;
1047
1048         /*
1049          * Discover both paths even if they are not complete. We will
1050          * clean them up by calling tb_tunnel_deactivate() below in that
1051          * case.
1052          */
1053         path = tb_path_discover(down, TB_USB3_HOPID, NULL, -1,
1054                                 &tunnel->dst_port, "USB3 Down");
1055         if (!path) {
1056                 /* Just disable the downstream port */
1057                 tb_usb3_port_enable(down, false);
1058                 goto err_free;
1059         }
1060         tunnel->paths[TB_USB3_PATH_DOWN] = path;
1061         tb_usb3_init_path(tunnel->paths[TB_USB3_PATH_DOWN]);
1062
1063         path = tb_path_discover(tunnel->dst_port, -1, down, TB_USB3_HOPID, NULL,
1064                                 "USB3 Up");
1065         if (!path)
1066                 goto err_deactivate;
1067         tunnel->paths[TB_USB3_PATH_UP] = path;
1068         tb_usb3_init_path(tunnel->paths[TB_USB3_PATH_UP]);
1069
1070         /* Validate that the tunnel is complete */
1071         if (!tb_port_is_usb3_up(tunnel->dst_port)) {
1072                 tb_port_warn(tunnel->dst_port,
1073                              "path does not end on an USB3 adapter, cleaning up\n");
1074                 goto err_deactivate;
1075         }
1076
1077         if (down != tunnel->src_port) {
1078                 tb_tunnel_warn(tunnel, "path is not complete, cleaning up\n");
1079                 goto err_deactivate;
1080         }
1081
1082         if (!tb_usb3_port_is_enabled(tunnel->dst_port)) {
1083                 tb_tunnel_warn(tunnel,
1084                                "tunnel is not fully activated, cleaning up\n");
1085                 goto err_deactivate;
1086         }
1087
1088         if (!tb_route(down->sw)) {
1089                 int ret;
1090
1091                 /*
1092                  * Read the initial bandwidth allocation for the first
1093                  * hop tunnel.
1094                  */
1095                 ret = usb4_usb3_port_allocated_bandwidth(down,
1096                         &tunnel->allocated_up, &tunnel->allocated_down);
1097                 if (ret)
1098                         goto err_deactivate;
1099
1100                 tb_tunnel_dbg(tunnel, "currently allocated bandwidth %d/%d Mb/s\n",
1101                               tunnel->allocated_up, tunnel->allocated_down);
1102
1103                 tunnel->init = tb_usb3_init;
1104                 tunnel->consumed_bandwidth = tb_usb3_consumed_bandwidth;
1105                 tunnel->release_unused_bandwidth =
1106                         tb_usb3_release_unused_bandwidth;
1107                 tunnel->reclaim_available_bandwidth =
1108                         tb_usb3_reclaim_available_bandwidth;
1109         }
1110
1111         tb_tunnel_dbg(tunnel, "discovered\n");
1112         return tunnel;
1113
1114 err_deactivate:
1115         tb_tunnel_deactivate(tunnel);
1116 err_free:
1117         tb_tunnel_free(tunnel);
1118
1119         return NULL;
1120 }
1121
1122 /**
1123  * tb_tunnel_alloc_usb3() - allocate a USB3 tunnel
1124  * @tb: Pointer to the domain structure
1125  * @up: USB3 upstream adapter port
1126  * @down: USB3 downstream adapter port
1127  * @max_up: Maximum available upstream bandwidth for the USB3 tunnel (%0
1128  *          if not limited).
1129  * @max_down: Maximum available downstream bandwidth for the USB3 tunnel
1130  *            (%0 if not limited).
1131  *
1132  * Allocate an USB3 tunnel. The ports must be of type @TB_TYPE_USB3_UP and
1133  * @TB_TYPE_USB3_DOWN.
1134  *
1135  * Return: Returns a tb_tunnel on success or %NULL on failure.
1136  */
1137 struct tb_tunnel *tb_tunnel_alloc_usb3(struct tb *tb, struct tb_port *up,
1138                                        struct tb_port *down, int max_up,
1139                                        int max_down)
1140 {
1141         struct tb_tunnel *tunnel;
1142         struct tb_path *path;
1143         int max_rate = 0;
1144
1145         /*
1146          * Check that we have enough bandwidth available for the new
1147          * USB3 tunnel.
1148          */
1149         if (max_up > 0 || max_down > 0) {
1150                 max_rate = tb_usb3_max_link_rate(down, up);
1151                 if (max_rate < 0)
1152                         return NULL;
1153
1154                 /* Only 90% can be allocated for USB3 isochronous transfers */
1155                 max_rate = max_rate * 90 / 100;
1156                 tb_port_dbg(up, "required bandwidth for USB3 tunnel %d Mb/s\n",
1157                             max_rate);
1158
1159                 if (max_rate > max_up || max_rate > max_down) {
1160                         tb_port_warn(up, "not enough bandwidth for USB3 tunnel\n");
1161                         return NULL;
1162                 }
1163         }
1164
1165         tunnel = tb_tunnel_alloc(tb, 2, TB_TUNNEL_USB3);
1166         if (!tunnel)
1167                 return NULL;
1168
1169         tunnel->activate = tb_usb3_activate;
1170         tunnel->src_port = down;
1171         tunnel->dst_port = up;
1172         tunnel->max_up = max_up;
1173         tunnel->max_down = max_down;
1174
1175         path = tb_path_alloc(tb, down, TB_USB3_HOPID, up, TB_USB3_HOPID, 0,
1176                              "USB3 Down");
1177         if (!path) {
1178                 tb_tunnel_free(tunnel);
1179                 return NULL;
1180         }
1181         tb_usb3_init_path(path);
1182         tunnel->paths[TB_USB3_PATH_DOWN] = path;
1183
1184         path = tb_path_alloc(tb, up, TB_USB3_HOPID, down, TB_USB3_HOPID, 0,
1185                              "USB3 Up");
1186         if (!path) {
1187                 tb_tunnel_free(tunnel);
1188                 return NULL;
1189         }
1190         tb_usb3_init_path(path);
1191         tunnel->paths[TB_USB3_PATH_UP] = path;
1192
1193         if (!tb_route(down->sw)) {
1194                 tunnel->allocated_up = max_rate;
1195                 tunnel->allocated_down = max_rate;
1196
1197                 tunnel->init = tb_usb3_init;
1198                 tunnel->consumed_bandwidth = tb_usb3_consumed_bandwidth;
1199                 tunnel->release_unused_bandwidth =
1200                         tb_usb3_release_unused_bandwidth;
1201                 tunnel->reclaim_available_bandwidth =
1202                         tb_usb3_reclaim_available_bandwidth;
1203         }
1204
1205         return tunnel;
1206 }
1207
1208 /**
1209  * tb_tunnel_free() - free a tunnel
1210  * @tunnel: Tunnel to be freed
1211  *
1212  * Frees a tunnel. The tunnel does not need to be deactivated.
1213  */
1214 void tb_tunnel_free(struct tb_tunnel *tunnel)
1215 {
1216         int i;
1217
1218         if (!tunnel)
1219                 return;
1220
1221         for (i = 0; i < tunnel->npaths; i++) {
1222                 if (tunnel->paths[i])
1223                         tb_path_free(tunnel->paths[i]);
1224         }
1225
1226         kfree(tunnel->paths);
1227         kfree(tunnel);
1228 }
1229
1230 /**
1231  * tb_tunnel_is_invalid - check whether an activated path is still valid
1232  * @tunnel: Tunnel to check
1233  */
1234 bool tb_tunnel_is_invalid(struct tb_tunnel *tunnel)
1235 {
1236         int i;
1237
1238         for (i = 0; i < tunnel->npaths; i++) {
1239                 WARN_ON(!tunnel->paths[i]->activated);
1240                 if (tb_path_is_invalid(tunnel->paths[i]))
1241                         return true;
1242         }
1243
1244         return false;
1245 }
1246
1247 /**
1248  * tb_tunnel_restart() - activate a tunnel after a hardware reset
1249  * @tunnel: Tunnel to restart
1250  *
1251  * Return: 0 on success and negative errno in case if failure
1252  */
1253 int tb_tunnel_restart(struct tb_tunnel *tunnel)
1254 {
1255         int res, i;
1256
1257         tb_tunnel_dbg(tunnel, "activating\n");
1258
1259         /*
1260          * Make sure all paths are properly disabled before enabling
1261          * them again.
1262          */
1263         for (i = 0; i < tunnel->npaths; i++) {
1264                 if (tunnel->paths[i]->activated) {
1265                         tb_path_deactivate(tunnel->paths[i]);
1266                         tunnel->paths[i]->activated = false;
1267                 }
1268         }
1269
1270         if (tunnel->init) {
1271                 res = tunnel->init(tunnel);
1272                 if (res)
1273                         return res;
1274         }
1275
1276         for (i = 0; i < tunnel->npaths; i++) {
1277                 res = tb_path_activate(tunnel->paths[i]);
1278                 if (res)
1279                         goto err;
1280         }
1281
1282         if (tunnel->activate) {
1283                 res = tunnel->activate(tunnel, true);
1284                 if (res)
1285                         goto err;
1286         }
1287
1288         return 0;
1289
1290 err:
1291         tb_tunnel_warn(tunnel, "activation failed\n");
1292         tb_tunnel_deactivate(tunnel);
1293         return res;
1294 }
1295
1296 /**
1297  * tb_tunnel_activate() - activate a tunnel
1298  * @tunnel: Tunnel to activate
1299  *
1300  * Return: Returns 0 on success or an error code on failure.
1301  */
1302 int tb_tunnel_activate(struct tb_tunnel *tunnel)
1303 {
1304         int i;
1305
1306         for (i = 0; i < tunnel->npaths; i++) {
1307                 if (tunnel->paths[i]->activated) {
1308                         tb_tunnel_WARN(tunnel,
1309                                        "trying to activate an already activated tunnel\n");
1310                         return -EINVAL;
1311                 }
1312         }
1313
1314         return tb_tunnel_restart(tunnel);
1315 }
1316
1317 /**
1318  * tb_tunnel_deactivate() - deactivate a tunnel
1319  * @tunnel: Tunnel to deactivate
1320  */
1321 void tb_tunnel_deactivate(struct tb_tunnel *tunnel)
1322 {
1323         int i;
1324
1325         tb_tunnel_dbg(tunnel, "deactivating\n");
1326
1327         if (tunnel->activate)
1328                 tunnel->activate(tunnel, false);
1329
1330         for (i = 0; i < tunnel->npaths; i++) {
1331                 if (tunnel->paths[i] && tunnel->paths[i]->activated)
1332                         tb_path_deactivate(tunnel->paths[i]);
1333         }
1334 }
1335
1336 /**
1337  * tb_tunnel_port_on_path() - Does the tunnel go through port
1338  * @tunnel: Tunnel to check
1339  * @port: Port to check
1340  *
1341  * Returns true if @tunnel goes through @port (direction does not matter),
1342  * false otherwise.
1343  */
1344 bool tb_tunnel_port_on_path(const struct tb_tunnel *tunnel,
1345                             const struct tb_port *port)
1346 {
1347         int i;
1348
1349         for (i = 0; i < tunnel->npaths; i++) {
1350                 if (!tunnel->paths[i])
1351                         continue;
1352
1353                 if (tb_path_port_on_path(tunnel->paths[i], port))
1354                         return true;
1355         }
1356
1357         return false;
1358 }
1359
1360 static bool tb_tunnel_is_active(const struct tb_tunnel *tunnel)
1361 {
1362         int i;
1363
1364         for (i = 0; i < tunnel->npaths; i++) {
1365                 if (!tunnel->paths[i])
1366                         return false;
1367                 if (!tunnel->paths[i]->activated)
1368                         return false;
1369         }
1370
1371         return true;
1372 }
1373
1374 /**
1375  * tb_tunnel_consumed_bandwidth() - Return bandwidth consumed by the tunnel
1376  * @tunnel: Tunnel to check
1377  * @consumed_up: Consumed bandwidth in Mb/s from @dst_port to @src_port.
1378  *               Can be %NULL.
1379  * @consumed_down: Consumed bandwidth in Mb/s from @src_port to @dst_port.
1380  *                 Can be %NULL.
1381  *
1382  * Stores the amount of isochronous bandwidth @tunnel consumes in
1383  * @consumed_up and @consumed_down. In case of success returns %0,
1384  * negative errno otherwise.
1385  */
1386 int tb_tunnel_consumed_bandwidth(struct tb_tunnel *tunnel, int *consumed_up,
1387                                  int *consumed_down)
1388 {
1389         int up_bw = 0, down_bw = 0;
1390
1391         if (!tb_tunnel_is_active(tunnel))
1392                 goto out;
1393
1394         if (tunnel->consumed_bandwidth) {
1395                 int ret;
1396
1397                 ret = tunnel->consumed_bandwidth(tunnel, &up_bw, &down_bw);
1398                 if (ret)
1399                         return ret;
1400
1401                 tb_tunnel_dbg(tunnel, "consumed bandwidth %d/%d Mb/s\n", up_bw,
1402                               down_bw);
1403         }
1404
1405 out:
1406         if (consumed_up)
1407                 *consumed_up = up_bw;
1408         if (consumed_down)
1409                 *consumed_down = down_bw;
1410
1411         return 0;
1412 }
1413
1414 /**
1415  * tb_tunnel_release_unused_bandwidth() - Release unused bandwidth
1416  * @tunnel: Tunnel whose unused bandwidth to release
1417  *
1418  * If tunnel supports dynamic bandwidth management (USB3 tunnels at the
1419  * moment) this function makes it to release all the unused bandwidth.
1420  *
1421  * Returns %0 in case of success and negative errno otherwise.
1422  */
1423 int tb_tunnel_release_unused_bandwidth(struct tb_tunnel *tunnel)
1424 {
1425         if (!tb_tunnel_is_active(tunnel))
1426                 return 0;
1427
1428         if (tunnel->release_unused_bandwidth) {
1429                 int ret;
1430
1431                 ret = tunnel->release_unused_bandwidth(tunnel);
1432                 if (ret)
1433                         return ret;
1434         }
1435
1436         return 0;
1437 }
1438
1439 /**
1440  * tb_tunnel_reclaim_available_bandwidth() - Reclaim available bandwidth
1441  * @tunnel: Tunnel reclaiming available bandwidth
1442  * @available_up: Available upstream bandwidth (in Mb/s)
1443  * @available_down: Available downstream bandwidth (in Mb/s)
1444  *
1445  * Reclaims bandwidth from @available_up and @available_down and updates
1446  * the variables accordingly (e.g decreases both according to what was
1447  * reclaimed by the tunnel). If nothing was reclaimed the values are
1448  * kept as is.
1449  */
1450 void tb_tunnel_reclaim_available_bandwidth(struct tb_tunnel *tunnel,
1451                                            int *available_up,
1452                                            int *available_down)
1453 {
1454         if (!tb_tunnel_is_active(tunnel))
1455                 return;
1456
1457         if (tunnel->reclaim_available_bandwidth)
1458                 tunnel->reclaim_available_bandwidth(tunnel, available_up,
1459                                                     available_down);
1460 }