drivers/thunderbolt/xdomain.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Thunderbolt XDomain discovery protocol support
   4  *
   5  * Copyright (C) 2017, Intel Corporation
   6  * Authors: Michael Jamet <michael.jamet@intel.com>
   7  *          Mika Westerberg <mika.westerberg@linux.intel.com>
   8  */
   9
  10 #include <linux/device.h>
  11 #include <linux/delay.h>
  12 #include <linux/kmod.h>
  13 #include <linux/module.h>
  14 #include <linux/pm_runtime.h>
  15 #include <linux/prandom.h>
  16 #include <linux/string_helpers.h>
  17 #include <linux/utsname.h>
  18 #include <linux/uuid.h>
  19 #include <linux/workqueue.h>
  20
  21 #include "tb.h"
  22
  23 #define XDOMAIN_SHORT_TIMEOUT                   100     /* ms */
  24 #define XDOMAIN_DEFAULT_TIMEOUT                 1000    /* ms */
  25 #define XDOMAIN_BONDING_TIMEOUT                 10000   /* ms */
  26 #define XDOMAIN_RETRIES                         10
  27 #define XDOMAIN_DEFAULT_MAX_HOPID               15
  28
  29 enum {
  30         XDOMAIN_STATE_INIT,
  31         XDOMAIN_STATE_UUID,
  32         XDOMAIN_STATE_LINK_STATUS,
  33         XDOMAIN_STATE_LINK_STATE_CHANGE,
  34         XDOMAIN_STATE_LINK_STATUS2,
  35         XDOMAIN_STATE_BONDING_UUID_LOW,
  36         XDOMAIN_STATE_BONDING_UUID_HIGH,
  37         XDOMAIN_STATE_PROPERTIES,
  38         XDOMAIN_STATE_ENUMERATED,
  39         XDOMAIN_STATE_ERROR,
  40 };
  41
  42 static const char * const state_names[] = {
  43         [XDOMAIN_STATE_INIT] = "INIT",
  44         [XDOMAIN_STATE_UUID] = "UUID",
  45         [XDOMAIN_STATE_LINK_STATUS] = "LINK_STATUS",
  46         [XDOMAIN_STATE_LINK_STATE_CHANGE] = "LINK_STATE_CHANGE",
  47         [XDOMAIN_STATE_LINK_STATUS2] = "LINK_STATUS2",
  48         [XDOMAIN_STATE_BONDING_UUID_LOW] = "BONDING_UUID_LOW",
  49         [XDOMAIN_STATE_BONDING_UUID_HIGH] = "BONDING_UUID_HIGH",
  50         [XDOMAIN_STATE_PROPERTIES] = "PROPERTIES",
  51         [XDOMAIN_STATE_ENUMERATED] = "ENUMERATED",
  52         [XDOMAIN_STATE_ERROR] = "ERROR",
  53 };
  54
  55 struct xdomain_request_work {
  56         struct work_struct work;
  57         struct tb_xdp_header *pkg;
  58         struct tb *tb;
  59 };
  60
  61 static bool tb_xdomain_enabled = true;
  62 module_param_named(xdomain, tb_xdomain_enabled, bool, 0444);
  63 MODULE_PARM_DESC(xdomain, "allow XDomain protocol (default: true)");
  64
  65 /*
  66  * Serializes access to the properties and protocol handlers below. If
  67  * you need to take both this lock and the struct tb_xdomain lock, take
  68  * this one first.
  69  */
  70 static DEFINE_MUTEX(xdomain_lock);
  71
  72 /* Properties exposed to the remote domains */
  73 static struct tb_property_dir *xdomain_property_dir;
  74 static u32 xdomain_property_block_gen;
  75
  76 /* Additional protocol handlers */
  77 static LIST_HEAD(protocol_handlers);
  78
  79 /* UUID for XDomain discovery protocol: b638d70e-42ff-40bb-97c2-90e2c0b2ff07 */
  80 static const uuid_t tb_xdp_uuid =
  81         UUID_INIT(0xb638d70e, 0x42ff, 0x40bb,
  82                   0x97, 0xc2, 0x90, 0xe2, 0xc0, 0xb2, 0xff, 0x07);
  83
  84 bool tb_is_xdomain_enabled(void)
  85 {
  86         return tb_xdomain_enabled && tb_acpi_is_xdomain_allowed();
  87 }
  88
  89 static bool tb_xdomain_match(const struct tb_cfg_request *req,
  90                              const struct ctl_pkg *pkg)
  91 {
  92         switch (pkg->frame.eof) {
  93         case TB_CFG_PKG_ERROR:
  94                 return true;
  95
  96         case TB_CFG_PKG_XDOMAIN_RESP: {
  97                 const struct tb_xdp_header *res_hdr = pkg->buffer;
  98                 const struct tb_xdp_header *req_hdr = req->request;
  99
 100                 if (pkg->frame.size < req->response_size / 4)
 101                         return false;
 102
 103                 /* Make sure route matches */
 104                 if ((res_hdr->xd_hdr.route_hi & ~BIT(31)) !=
 105                      req_hdr->xd_hdr.route_hi)
 106                         return false;
 107                 if ((res_hdr->xd_hdr.route_lo) != req_hdr->xd_hdr.route_lo)
 108                         return false;
 109
 110                 /* Check that the XDomain protocol matches */
 111                 if (!uuid_equal(&res_hdr->uuid, &req_hdr->uuid))
 112                         return false;
 113
 114                 return true;
 115         }
 116
 117         default:
 118                 return false;
 119         }
 120 }
 121
 122 static bool tb_xdomain_copy(struct tb_cfg_request *req,
 123                             const struct ctl_pkg *pkg)
 124 {
 125         memcpy(req->response, pkg->buffer, req->response_size);
 126         req->result.err = 0;
 127         return true;
 128 }
 129
 130 static void response_ready(void *data)
 131 {
 132         tb_cfg_request_put(data);
 133 }
 134
 135 static int __tb_xdomain_response(struct tb_ctl *ctl, const void *response,
 136                                  size_t size, enum tb_cfg_pkg_type type)
 137 {
 138         struct tb_cfg_request *req;
 139
 140         req = tb_cfg_request_alloc();
 141         if (!req)
 142                 return -ENOMEM;
 143
 144         req->match = tb_xdomain_match;
 145         req->copy = tb_xdomain_copy;
 146         req->request = response;
 147         req->request_size = size;
 148         req->request_type = type;
 149
 150         return tb_cfg_request(ctl, req, response_ready, req);
 151 }
 152
 153 /**
 154  * tb_xdomain_response() - Send a XDomain response message
 155  * @xd: XDomain to send the message
 156  * @response: Response to send
 157  * @size: Size of the response
 158  * @type: PDF type of the response
 159  *
 160  * This can be used to send a XDomain response message to the other
 161  * domain. No response for the message is expected.
 162  *
 163  * Return: %0 in case of success and negative errno in case of failure
 164  */
 165 int tb_xdomain_response(struct tb_xdomain *xd, const void *response,
 166                         size_t size, enum tb_cfg_pkg_type type)
 167 {
 168         return __tb_xdomain_response(xd->tb->ctl, response, size, type);
 169 }
 170 EXPORT_SYMBOL_GPL(tb_xdomain_response);
 171
 172 static int __tb_xdomain_request(struct tb_ctl *ctl, const void *request,
 173         size_t request_size, enum tb_cfg_pkg_type request_type, void *response,
 174         size_t response_size, enum tb_cfg_pkg_type response_type,
 175         unsigned int timeout_msec)
 176 {
 177         struct tb_cfg_request *req;
 178         struct tb_cfg_result res;
 179
 180         req = tb_cfg_request_alloc();
 181         if (!req)
 182                 return -ENOMEM;
 183
 184         req->match = tb_xdomain_match;
 185         req->copy = tb_xdomain_copy;
 186         req->request = request;
 187         req->request_size = request_size;
 188         req->request_type = request_type;
 189         req->response = response;
 190         req->response_size = response_size;
 191         req->response_type = response_type;
 192
 193         res = tb_cfg_request_sync(ctl, req, timeout_msec);
 194
 195         tb_cfg_request_put(req);
 196
 197         return res.err == 1 ? -EIO : res.err;
 198 }
 199
 200 /**
 201  * tb_xdomain_request() - Send a XDomain request
 202  * @xd: XDomain to send the request
 203  * @request: Request to send
 204  * @request_size: Size of the request in bytes
 205  * @request_type: PDF type of the request
 206  * @response: Response is copied here
 207  * @response_size: Expected size of the response in bytes
 208  * @response_type: Expected PDF type of the response
 209  * @timeout_msec: Timeout in milliseconds to wait for the response
 210  *
 211  * This function can be used to send XDomain control channel messages to
 212  * the other domain. The function waits until the response is received
 213  * or when timeout triggers. Whichever comes first.
 214  *
 215  * Return: %0 in case of success and negative errno in case of failure
 216  */
 217 int tb_xdomain_request(struct tb_xdomain *xd, const void *request,
 218         size_t request_size, enum tb_cfg_pkg_type request_type,
 219         void *response, size_t response_size,
 220         enum tb_cfg_pkg_type response_type, unsigned int timeout_msec)
 221 {
 222         return __tb_xdomain_request(xd->tb->ctl, request, request_size,
 223                                     request_type, response, response_size,
 224                                     response_type, timeout_msec);
 225 }
 226 EXPORT_SYMBOL_GPL(tb_xdomain_request);
 227
 228 static inline void tb_xdp_fill_header(struct tb_xdp_header *hdr, u64 route,
 229         u8 sequence, enum tb_xdp_type type, size_t size)
 230 {
 231         u32 length_sn;
 232
 233         length_sn = (size - sizeof(hdr->xd_hdr)) / 4;
 234         length_sn |= (sequence << TB_XDOMAIN_SN_SHIFT) & TB_XDOMAIN_SN_MASK;
 235
 236         hdr->xd_hdr.route_hi = upper_32_bits(route);
 237         hdr->xd_hdr.route_lo = lower_32_bits(route);
 238         hdr->xd_hdr.length_sn = length_sn;
 239         hdr->type = type;
 240         memcpy(&hdr->uuid, &tb_xdp_uuid, sizeof(tb_xdp_uuid));
 241 }
 242
 243 static int tb_xdp_handle_error(const struct tb_xdp_error_response *res)
 244 {
 245         if (res->hdr.type != ERROR_RESPONSE)
 246                 return 0;
 247
 248         switch (res->error) {
 249         case ERROR_UNKNOWN_PACKET:
 250         case ERROR_UNKNOWN_DOMAIN:
 251                 return -EIO;
 252         case ERROR_NOT_SUPPORTED:
 253                 return -ENOTSUPP;
 254         case ERROR_NOT_READY:
 255                 return -EAGAIN;
 256         default:
 257                 break;
 258         }
 259
 260         return 0;
 261 }
 262
 263 static int tb_xdp_uuid_request(struct tb_ctl *ctl, u64 route, int retry,
 264                                uuid_t *uuid, u64 *remote_route)
 265 {
 266         struct tb_xdp_uuid_response res;
 267         struct tb_xdp_uuid req;
 268         int ret;
 269
 270         memset(&req, 0, sizeof(req));
 271         tb_xdp_fill_header(&req.hdr, route, retry % 4, UUID_REQUEST,
 272                            sizeof(req));
 273
 274         memset(&res, 0, sizeof(res));
 275         ret = __tb_xdomain_request(ctl, &req, sizeof(req),
 276                                    TB_CFG_PKG_XDOMAIN_REQ, &res, sizeof(res),
 277                                    TB_CFG_PKG_XDOMAIN_RESP,
 278                                    XDOMAIN_DEFAULT_TIMEOUT);
 279         if (ret)
 280                 return ret;
 281
 282         ret = tb_xdp_handle_error(&res.err);
 283         if (ret)
 284                 return ret;
 285
 286         uuid_copy(uuid, &res.src_uuid);
 287         *remote_route = (u64)res.src_route_hi << 32 | res.src_route_lo;
 288
 289         return 0;
 290 }
 291
 292 static int tb_xdp_uuid_response(struct tb_ctl *ctl, u64 route, u8 sequence,
 293                                 const uuid_t *uuid)
 294 {
 295         struct tb_xdp_uuid_response res;
 296
 297         memset(&res, 0, sizeof(res));
 298         tb_xdp_fill_header(&res.hdr, route, sequence, UUID_RESPONSE,
 299                            sizeof(res));
 300
 301         uuid_copy(&res.src_uuid, uuid);
 302         res.src_route_hi = upper_32_bits(route);
 303         res.src_route_lo = lower_32_bits(route);
 304
 305         return __tb_xdomain_response(ctl, &res, sizeof(res),
 306                                      TB_CFG_PKG_XDOMAIN_RESP);
 307 }
 308
 309 static int tb_xdp_error_response(struct tb_ctl *ctl, u64 route, u8 sequence,
 310                                  enum tb_xdp_error error)
 311 {
 312         struct tb_xdp_error_response res;
 313
 314         memset(&res, 0, sizeof(res));
 315         tb_xdp_fill_header(&res.hdr, route, sequence, ERROR_RESPONSE,
 316                            sizeof(res));
 317         res.error = error;
 318
 319         return __tb_xdomain_response(ctl, &res, sizeof(res),
 320                                      TB_CFG_PKG_XDOMAIN_RESP);
 321 }
 322
 323 static int tb_xdp_properties_request(struct tb_ctl *ctl, u64 route,
 324         const uuid_t *src_uuid, const uuid_t *dst_uuid, int retry,
 325         u32 **block, u32 *generation)
 326 {
 327         struct tb_xdp_properties_response *res;
 328         struct tb_xdp_properties req;
 329         u16 data_len, len;
 330         size_t total_size;
 331         u32 *data = NULL;
 332         int ret;
 333
 334         total_size = sizeof(*res) + TB_XDP_PROPERTIES_MAX_DATA_LENGTH * 4;
 335         res = kzalloc(total_size, GFP_KERNEL);
 336         if (!res)
 337                 return -ENOMEM;
 338
 339         memset(&req, 0, sizeof(req));
 340         tb_xdp_fill_header(&req.hdr, route, retry % 4, PROPERTIES_REQUEST,
 341                            sizeof(req));
 342         memcpy(&req.src_uuid, src_uuid, sizeof(*src_uuid));
 343         memcpy(&req.dst_uuid, dst_uuid, sizeof(*dst_uuid));
 344
 345         data_len = 0;
 346
 347         do {
 348                 ret = __tb_xdomain_request(ctl, &req, sizeof(req),
 349                                            TB_CFG_PKG_XDOMAIN_REQ, res,
 350                                            total_size, TB_CFG_PKG_XDOMAIN_RESP,
 351                                            XDOMAIN_DEFAULT_TIMEOUT);
 352                 if (ret)
 353                         goto err;
 354
 355                 ret = tb_xdp_handle_error(&res->err);
 356                 if (ret)
 357                         goto err;
 358
 359                 /*
 360                  * Package length includes the whole payload without the
 361                  * XDomain header. Validate first that the package is at
 362                  * least size of the response structure.
 363                  */
 364                 len = res->hdr.xd_hdr.length_sn & TB_XDOMAIN_LENGTH_MASK;
 365                 if (len < sizeof(*res) / 4) {
 366                         ret = -EINVAL;
 367                         goto err;
 368                 }
 369
 370                 len += sizeof(res->hdr.xd_hdr) / 4;
 371                 len -= sizeof(*res) / 4;
 372
 373                 if (res->offset != req.offset) {
 374                         ret = -EINVAL;
 375                         goto err;
 376                 }
 377
 378                 /*
 379                  * First time allocate block that has enough space for
 380                  * the whole properties block.
 381                  */
 382                 if (!data) {
 383                         data_len = res->data_length;
 384                         if (data_len > TB_XDP_PROPERTIES_MAX_LENGTH) {
 385                                 ret = -E2BIG;
 386                                 goto err;
 387                         }
 388
 389                         data = kcalloc(data_len, sizeof(u32), GFP_KERNEL);
 390                         if (!data) {
 391                                 ret = -ENOMEM;
 392                                 goto err;
 393                         }
 394                 }
 395
 396                 memcpy(data + req.offset, res->data, len * 4);
 397                 req.offset += len;
 398         } while (!data_len || req.offset < data_len);
 399
 400         *block = data;
 401         *generation = res->generation;
 402
 403         kfree(res);
 404
 405         return data_len;
 406
 407 err:
 408         kfree(data);
 409         kfree(res);
 410
 411         return ret;
 412 }
 413
 414 static int tb_xdp_properties_response(struct tb *tb, struct tb_ctl *ctl,
 415         struct tb_xdomain *xd, u8 sequence, const struct tb_xdp_properties *req)
 416 {
 417         struct tb_xdp_properties_response *res;
 418         size_t total_size;
 419         u16 len;
 420         int ret;
 421
 422         /*
 423          * Currently we expect all requests to be directed to us. The
 424          * protocol supports forwarding, though which we might add
 425          * support later on.
 426          */
 427         if (!uuid_equal(xd->local_uuid, &req->dst_uuid)) {
 428                 tb_xdp_error_response(ctl, xd->route, sequence,
 429                                       ERROR_UNKNOWN_DOMAIN);
 430                 return 0;
 431         }
 432
 433         mutex_lock(&xd->lock);
 434
 435         if (req->offset >= xd->local_property_block_len) {
 436                 mutex_unlock(&xd->lock);
 437                 return -EINVAL;
 438         }
 439
 440         len = xd->local_property_block_len - req->offset;
 441         len = min_t(u16, len, TB_XDP_PROPERTIES_MAX_DATA_LENGTH);
 442         total_size = sizeof(*res) + len * 4;
 443
 444         res = kzalloc(total_size, GFP_KERNEL);
 445         if (!res) {
 446                 mutex_unlock(&xd->lock);
 447                 return -ENOMEM;
 448         }
 449
 450         tb_xdp_fill_header(&res->hdr, xd->route, sequence, PROPERTIES_RESPONSE,
 451                            total_size);
 452         res->generation = xd->local_property_block_gen;
 453         res->data_length = xd->local_property_block_len;
 454         res->offset = req->offset;
 455         uuid_copy(&res->src_uuid, xd->local_uuid);
 456         uuid_copy(&res->dst_uuid, &req->src_uuid);
 457         memcpy(res->data, &xd->local_property_block[req->offset], len * 4);
 458
 459         mutex_unlock(&xd->lock);
 460
 461         ret = __tb_xdomain_response(ctl, res, total_size,
 462                                     TB_CFG_PKG_XDOMAIN_RESP);
 463
 464         kfree(res);
 465         return ret;
 466 }
 467
 468 static int tb_xdp_properties_changed_request(struct tb_ctl *ctl, u64 route,
 469                                              int retry, const uuid_t *uuid)
 470 {
 471         struct tb_xdp_properties_changed_response res;
 472         struct tb_xdp_properties_changed req;
 473         int ret;
 474
 475         memset(&req, 0, sizeof(req));
 476         tb_xdp_fill_header(&req.hdr, route, retry % 4,
 477                            PROPERTIES_CHANGED_REQUEST, sizeof(req));
 478         uuid_copy(&req.src_uuid, uuid);
 479
 480         memset(&res, 0, sizeof(res));
 481         ret = __tb_xdomain_request(ctl, &req, sizeof(req),
 482                                    TB_CFG_PKG_XDOMAIN_REQ, &res, sizeof(res),
 483                                    TB_CFG_PKG_XDOMAIN_RESP,
 484                                    XDOMAIN_DEFAULT_TIMEOUT);
 485         if (ret)
 486                 return ret;
 487
 488         return tb_xdp_handle_error(&res.err);
 489 }
 490
 491 static int
 492 tb_xdp_properties_changed_response(struct tb_ctl *ctl, u64 route, u8 sequence)
 493 {
 494         struct tb_xdp_properties_changed_response res;
 495
 496         memset(&res, 0, sizeof(res));
 497         tb_xdp_fill_header(&res.hdr, route, sequence,
 498                            PROPERTIES_CHANGED_RESPONSE, sizeof(res));
 499         return __tb_xdomain_response(ctl, &res, sizeof(res),
 500                                      TB_CFG_PKG_XDOMAIN_RESP);
 501 }
 502
 503 static int tb_xdp_link_state_status_request(struct tb_ctl *ctl, u64 route,
 504                                             u8 sequence, u8 *slw, u8 *tlw,
 505                                             u8 *sls, u8 *tls)
 506 {
 507         struct tb_xdp_link_state_status_response res;
 508         struct tb_xdp_link_state_status req;
 509         int ret;
 510
 511         memset(&req, 0, sizeof(req));
 512         tb_xdp_fill_header(&req.hdr, route, sequence, LINK_STATE_STATUS_REQUEST,
 513                            sizeof(req));
 514
 515         memset(&res, 0, sizeof(res));
 516         ret = __tb_xdomain_request(ctl, &req, sizeof(req), TB_CFG_PKG_XDOMAIN_REQ,
 517                                    &res, sizeof(res), TB_CFG_PKG_XDOMAIN_RESP,
 518                                    XDOMAIN_DEFAULT_TIMEOUT);
 519         if (ret)
 520                 return ret;
 521
 522         ret = tb_xdp_handle_error(&res.err);
 523         if (ret)
 524                 return ret;
 525
 526         if (res.status != 0)
 527                 return -EREMOTEIO;
 528
 529         *slw = res.slw;
 530         *tlw = res.tlw;
 531         *sls = res.sls;
 532         *tls = res.tls;
 533
 534         return 0;
 535 }
 536
 537 static int tb_xdp_link_state_status_response(struct tb *tb, struct tb_ctl *ctl,
 538                                              struct tb_xdomain *xd, u8 sequence)
 539 {
 540         struct tb_xdp_link_state_status_response res;
 541         struct tb_port *port = tb_xdomain_downstream_port(xd);
 542         u32 val[2];
 543         int ret;
 544
 545         memset(&res, 0, sizeof(res));
 546         tb_xdp_fill_header(&res.hdr, xd->route, sequence,
 547                            LINK_STATE_STATUS_RESPONSE, sizeof(res));
 548
 549         ret = tb_port_read(port, val, TB_CFG_PORT,
 550                            port->cap_phy + LANE_ADP_CS_0, ARRAY_SIZE(val));
 551         if (ret)
 552                 return ret;
 553
 554         res.slw = (val[0] & LANE_ADP_CS_0_SUPPORTED_WIDTH_MASK) >>
 555                         LANE_ADP_CS_0_SUPPORTED_WIDTH_SHIFT;
 556         res.sls = (val[0] & LANE_ADP_CS_0_SUPPORTED_SPEED_MASK) >>
 557                         LANE_ADP_CS_0_SUPPORTED_SPEED_SHIFT;
 558         res.tls = val[1] & LANE_ADP_CS_1_TARGET_SPEED_MASK;
 559         res.tlw = (val[1] & LANE_ADP_CS_1_TARGET_WIDTH_MASK) >>
 560                         LANE_ADP_CS_1_TARGET_WIDTH_SHIFT;
 561
 562         return __tb_xdomain_response(ctl, &res, sizeof(res),
 563                                      TB_CFG_PKG_XDOMAIN_RESP);
 564 }
 565
 566 static int tb_xdp_link_state_change_request(struct tb_ctl *ctl, u64 route,
 567                                             u8 sequence, u8 tlw, u8 tls)
 568 {
 569         struct tb_xdp_link_state_change_response res;
 570         struct tb_xdp_link_state_change req;
 571         int ret;
 572
 573         memset(&req, 0, sizeof(req));
 574         tb_xdp_fill_header(&req.hdr, route, sequence, LINK_STATE_CHANGE_REQUEST,
 575                            sizeof(req));
 576         req.tlw = tlw;
 577         req.tls = tls;
 578
 579         memset(&res, 0, sizeof(res));
 580         ret = __tb_xdomain_request(ctl, &req, sizeof(req), TB_CFG_PKG_XDOMAIN_REQ,
 581                                    &res, sizeof(res), TB_CFG_PKG_XDOMAIN_RESP,
 582                                    XDOMAIN_DEFAULT_TIMEOUT);
 583         if (ret)
 584                 return ret;
 585
 586         ret = tb_xdp_handle_error(&res.err);
 587         if (ret)
 588                 return ret;
 589
 590         return res.status != 0 ? -EREMOTEIO : 0;
 591 }
 592
 593 static int tb_xdp_link_state_change_response(struct tb_ctl *ctl, u64 route,
 594                                              u8 sequence, u32 status)
 595 {
 596         struct tb_xdp_link_state_change_response res;
 597
 598         memset(&res, 0, sizeof(res));
 599         tb_xdp_fill_header(&res.hdr, route, sequence, LINK_STATE_CHANGE_RESPONSE,
 600                            sizeof(res));
 601
 602         res.status = status;
 603
 604         return __tb_xdomain_response(ctl, &res, sizeof(res),
 605                                      TB_CFG_PKG_XDOMAIN_RESP);
 606 }
 607
 608 /**
 609  * tb_register_protocol_handler() - Register protocol handler
 610  * @handler: Handler to register
 611  *
 612  * This allows XDomain service drivers to hook into incoming XDomain
 613  * messages. After this function is called the service driver needs to
 614  * be able to handle calls to callback whenever a package with the
 615  * registered protocol is received.
 616  */
 617 int tb_register_protocol_handler(struct tb_protocol_handler *handler)
 618 {
 619         if (!handler->uuid || !handler->callback)
 620                 return -EINVAL;
 621         if (uuid_equal(handler->uuid, &tb_xdp_uuid))
 622                 return -EINVAL;
 623
 624         mutex_lock(&xdomain_lock);
 625         list_add_tail(&handler->list, &protocol_handlers);
 626         mutex_unlock(&xdomain_lock);
 627
 628         return 0;
 629 }
 630 EXPORT_SYMBOL_GPL(tb_register_protocol_handler);
 631
 632 /**
 633  * tb_unregister_protocol_handler() - Unregister protocol handler
 634  * @handler: Handler to unregister
 635  *
 636  * Removes the previously registered protocol handler.
 637  */
 638 void tb_unregister_protocol_handler(struct tb_protocol_handler *handler)
 639 {
 640         mutex_lock(&xdomain_lock);
 641         list_del_init(&handler->list);
 642         mutex_unlock(&xdomain_lock);
 643 }
 644 EXPORT_SYMBOL_GPL(tb_unregister_protocol_handler);
 645
 646 static void update_property_block(struct tb_xdomain *xd)
 647 {
 648         mutex_lock(&xdomain_lock);
 649         mutex_lock(&xd->lock);
 650         /*
 651          * If the local property block is not up-to-date, rebuild it now
 652          * based on the global property template.
 653          */
 654         if (!xd->local_property_block ||
 655             xd->local_property_block_gen < xdomain_property_block_gen) {
 656                 struct tb_property_dir *dir;
 657                 int ret, block_len;
 658                 u32 *block;
 659
 660                 dir = tb_property_copy_dir(xdomain_property_dir);
 661                 if (!dir) {
 662                         dev_warn(&xd->dev, "failed to copy properties\n");
 663                         goto out_unlock;
 664                 }
 665
 666                 /* Fill in non-static properties now */
 667                 tb_property_add_text(dir, "deviceid", utsname()->nodename);
 668                 tb_property_add_immediate(dir, "maxhopid", xd->local_max_hopid);
 669
 670                 ret = tb_property_format_dir(dir, NULL, 0);
 671                 if (ret < 0) {
 672                         dev_warn(&xd->dev, "local property block creation failed\n");
 673                         tb_property_free_dir(dir);
 674                         goto out_unlock;
 675                 }
 676
 677                 block_len = ret;
 678                 block = kcalloc(block_len, sizeof(*block), GFP_KERNEL);
 679                 if (!block) {
 680                         tb_property_free_dir(dir);
 681                         goto out_unlock;
 682                 }
 683
 684                 ret = tb_property_format_dir(dir, block, block_len);
 685                 if (ret) {
 686                         dev_warn(&xd->dev, "property block generation failed\n");
 687                         tb_property_free_dir(dir);
 688                         kfree(block);
 689                         goto out_unlock;
 690                 }
 691
 692                 tb_property_free_dir(dir);
 693                 /* Release the previous block */
 694                 kfree(xd->local_property_block);
 695                 /* Assign new one */
 696                 xd->local_property_block = block;
 697                 xd->local_property_block_len = block_len;
 698                 xd->local_property_block_gen = xdomain_property_block_gen;
 699         }
 700
 701 out_unlock:
 702         mutex_unlock(&xd->lock);
 703         mutex_unlock(&xdomain_lock);
 704 }
 705
 706 static void start_handshake(struct tb_xdomain *xd)
 707 {
 708         xd->state = XDOMAIN_STATE_INIT;
 709         queue_delayed_work(xd->tb->wq, &xd->state_work,
 710                            msecs_to_jiffies(XDOMAIN_SHORT_TIMEOUT));
 711 }
 712
 713 /* Can be called from state_work */
 714 static void __stop_handshake(struct tb_xdomain *xd)
 715 {
 716         cancel_delayed_work_sync(&xd->properties_changed_work);
 717         xd->properties_changed_retries = 0;
 718         xd->state_retries = 0;
 719 }
 720
 721 static void stop_handshake(struct tb_xdomain *xd)
 722 {
 723         cancel_delayed_work_sync(&xd->state_work);
 724         __stop_handshake(xd);
 725 }
 726
 727 static void tb_xdp_handle_request(struct work_struct *work)
 728 {
 729         struct xdomain_request_work *xw = container_of(work, typeof(*xw), work);
 730         const struct tb_xdp_header *pkg = xw->pkg;
 731         const struct tb_xdomain_header *xhdr = &pkg->xd_hdr;
 732         struct tb *tb = xw->tb;
 733         struct tb_ctl *ctl = tb->ctl;
 734         struct tb_xdomain *xd;
 735         const uuid_t *uuid;
 736         int ret = 0;
 737         u32 sequence;
 738         u64 route;
 739
 740         route = ((u64)xhdr->route_hi << 32 | xhdr->route_lo) & ~BIT_ULL(63);
 741         sequence = xhdr->length_sn & TB_XDOMAIN_SN_MASK;
 742         sequence >>= TB_XDOMAIN_SN_SHIFT;
 743
 744         mutex_lock(&tb->lock);
 745         if (tb->root_switch)
 746                 uuid = tb->root_switch->uuid;
 747         else
 748                 uuid = NULL;
 749         mutex_unlock(&tb->lock);
 750
 751         if (!uuid) {
 752                 tb_xdp_error_response(ctl, route, sequence, ERROR_NOT_READY);
 753                 goto out;
 754         }
 755
 756         xd = tb_xdomain_find_by_route_locked(tb, route);
 757         if (xd)
 758                 update_property_block(xd);
 759
 760         switch (pkg->type) {
 761         case PROPERTIES_REQUEST:
 762                 tb_dbg(tb, "%llx: received XDomain properties request\n", route);
 763                 if (xd) {
 764                         ret = tb_xdp_properties_response(tb, ctl, xd, sequence,
 765                                 (const struct tb_xdp_properties *)pkg);
 766                 }
 767                 break;
 768
 769         case PROPERTIES_CHANGED_REQUEST:
 770                 tb_dbg(tb, "%llx: received XDomain properties changed request\n",
 771                        route);
 772
 773                 ret = tb_xdp_properties_changed_response(ctl, route, sequence);
 774
 775                 /*
 776                  * Since the properties have been changed, let's update
 777                  * the xdomain related to this connection as well in
 778                  * case there is a change in services it offers.
 779                  */
 780                 if (xd && device_is_registered(&xd->dev))
 781                         queue_delayed_work(tb->wq, &xd->state_work,
 782                                            msecs_to_jiffies(XDOMAIN_SHORT_TIMEOUT));
 783                 break;
 784
 785         case UUID_REQUEST_OLD:
 786         case UUID_REQUEST:
 787                 tb_dbg(tb, "%llx: received XDomain UUID request\n", route);
 788                 ret = tb_xdp_uuid_response(ctl, route, sequence, uuid);
 789                 /*
 790                  * If we've stopped the discovery with an error such as
 791                  * timing out, we will restart the handshake now that we
 792                  * received UUID request from the remote host.
 793                  */
 794                 if (!ret && xd && xd->state == XDOMAIN_STATE_ERROR) {
 795                         dev_dbg(&xd->dev, "restarting handshake\n");
 796                         start_handshake(xd);
 797                 }
 798                 break;
 799
 800         case LINK_STATE_STATUS_REQUEST:
 801                 tb_dbg(tb, "%llx: received XDomain link state status request\n",
 802                        route);
 803
 804                 if (xd) {
 805                         ret = tb_xdp_link_state_status_response(tb, ctl, xd,
 806                                                                 sequence);
 807                 } else {
 808                         tb_xdp_error_response(ctl, route, sequence,
 809                                               ERROR_NOT_READY);
 810                 }
 811                 break;
 812
 813         case LINK_STATE_CHANGE_REQUEST:
 814                 tb_dbg(tb, "%llx: received XDomain link state change request\n",
 815                        route);
 816
 817                 if (xd && xd->state == XDOMAIN_STATE_BONDING_UUID_HIGH) {
 818                         const struct tb_xdp_link_state_change *lsc =
 819                                 (const struct tb_xdp_link_state_change *)pkg;
 820
 821                         ret = tb_xdp_link_state_change_response(ctl, route,
 822                                                                 sequence, 0);
 823                         xd->target_link_width = lsc->tlw;
 824                         queue_delayed_work(tb->wq, &xd->state_work,
 825                                            msecs_to_jiffies(XDOMAIN_SHORT_TIMEOUT));
 826                 } else {
 827                         tb_xdp_error_response(ctl, route, sequence,
 828                                               ERROR_NOT_READY);
 829                 }
 830                 break;
 831
 832         default:
 833                 tb_dbg(tb, "%llx: unknown XDomain request %#x\n", route, pkg->type);
 834                 tb_xdp_error_response(ctl, route, sequence,
 835                                       ERROR_NOT_SUPPORTED);
 836                 break;
 837         }
 838
 839         tb_xdomain_put(xd);
 840
 841         if (ret) {
 842                 tb_warn(tb, "failed to send XDomain response for %#x\n",
 843                         pkg->type);
 844         }
 845
 846 out:
 847         kfree(xw->pkg);
 848         kfree(xw);
 849
 850         tb_domain_put(tb);
 851 }
 852
 853 static bool
 854 tb_xdp_schedule_request(struct tb *tb, const struct tb_xdp_header *hdr,
 855                         size_t size)
 856 {
 857         struct xdomain_request_work *xw;
 858
 859         xw = kmalloc(sizeof(*xw), GFP_KERNEL);
 860         if (!xw)
 861                 return false;
 862
 863         INIT_WORK(&xw->work, tb_xdp_handle_request);
 864         xw->pkg = kmemdup(hdr, size, GFP_KERNEL);
 865         if (!xw->pkg) {
 866                 kfree(xw);
 867                 return false;
 868         }
 869         xw->tb = tb_domain_get(tb);
 870
 871         schedule_work(&xw->work);
 872         return true;
 873 }
 874
 875 /**
 876  * tb_register_service_driver() - Register XDomain service driver
 877  * @drv: Driver to register
 878  *
 879  * Registers new service driver from @drv to the bus.
 880  */
 881 int tb_register_service_driver(struct tb_service_driver *drv)
 882 {
 883         drv->driver.bus = &tb_bus_type;
 884         return driver_register(&drv->driver);
 885 }
 886 EXPORT_SYMBOL_GPL(tb_register_service_driver);
 887
 888 /**
 889  * tb_unregister_service_driver() - Unregister XDomain service driver
 890  * @drv: Driver to unregister
 891  *
 892  * Unregisters XDomain service driver from the bus.
 893  */
 894 void tb_unregister_service_driver(struct tb_service_driver *drv)
 895 {
 896         driver_unregister(&drv->driver);
 897 }
 898 EXPORT_SYMBOL_GPL(tb_unregister_service_driver);
 899
 900 static ssize_t key_show(struct device *dev, struct device_attribute *attr,
 901                         char *buf)
 902 {
 903         struct tb_service *svc = container_of(dev, struct tb_service, dev);
 904
 905         /*
 906          * It should be null terminated but anything else is pretty much
 907          * allowed.
 908          */
 909         return sysfs_emit(buf, "%*pE\n", (int)strlen(svc->key), svc->key);
 910 }
 911 static DEVICE_ATTR_RO(key);
 912
 913 static int get_modalias(const struct tb_service *svc, char *buf, size_t size)
 914 {
 915         return snprintf(buf, size, "tbsvc:k%sp%08Xv%08Xr%08X", svc->key,
 916                         svc->prtcid, svc->prtcvers, svc->prtcrevs);
 917 }
 918
 919 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
 920                              char *buf)
 921 {
 922         struct tb_service *svc = container_of(dev, struct tb_service, dev);
 923
 924         /* Full buffer size except new line and null termination */
 925         get_modalias(svc, buf, PAGE_SIZE - 2);
 926         return strlen(strcat(buf, "\n"));
 927 }
 928 static DEVICE_ATTR_RO(modalias);
 929
 930 static ssize_t prtcid_show(struct device *dev, struct device_attribute *attr,
 931                            char *buf)
 932 {
 933         struct tb_service *svc = container_of(dev, struct tb_service, dev);
 934
 935         return sysfs_emit(buf, "%u\n", svc->prtcid);
 936 }
 937 static DEVICE_ATTR_RO(prtcid);
 938
 939 static ssize_t prtcvers_show(struct device *dev, struct device_attribute *attr,
 940                              char *buf)
 941 {
 942         struct tb_service *svc = container_of(dev, struct tb_service, dev);
 943
 944         return sysfs_emit(buf, "%u\n", svc->prtcvers);
 945 }
 946 static DEVICE_ATTR_RO(prtcvers);
 947
 948 static ssize_t prtcrevs_show(struct device *dev, struct device_attribute *attr,
 949                              char *buf)
 950 {
 951         struct tb_service *svc = container_of(dev, struct tb_service, dev);
 952
 953         return sysfs_emit(buf, "%u\n", svc->prtcrevs);
 954 }
 955 static DEVICE_ATTR_RO(prtcrevs);
 956
 957 static ssize_t prtcstns_show(struct device *dev, struct device_attribute *attr,
 958                              char *buf)
 959 {
 960         struct tb_service *svc = container_of(dev, struct tb_service, dev);
 961
 962         return sysfs_emit(buf, "0x%08x\n", svc->prtcstns);
 963 }
 964 static DEVICE_ATTR_RO(prtcstns);
 965
 966 static struct attribute *tb_service_attrs[] = {
 967         &dev_attr_key.attr,
 968         &dev_attr_modalias.attr,
 969         &dev_attr_prtcid.attr,
 970         &dev_attr_prtcvers.attr,
 971         &dev_attr_prtcrevs.attr,
 972         &dev_attr_prtcstns.attr,
 973         NULL,
 974 };
 975
 976 static const struct attribute_group tb_service_attr_group = {
 977         .attrs = tb_service_attrs,
 978 };
 979
 980 static const struct attribute_group *tb_service_attr_groups[] = {
 981         &tb_service_attr_group,
 982         NULL,
 983 };
 984
 985 static int tb_service_uevent(const struct device *dev, struct kobj_uevent_env *env)
 986 {
 987         const struct tb_service *svc = container_of_const(dev, struct tb_service, dev);
 988         char modalias[64];
 989
 990         get_modalias(svc, modalias, sizeof(modalias));
 991         return add_uevent_var(env, "MODALIAS=%s", modalias);
 992 }
 993
 994 static void tb_service_release(struct device *dev)
 995 {
 996         struct tb_service *svc = container_of(dev, struct tb_service, dev);
 997         struct tb_xdomain *xd = tb_service_parent(svc);
 998
 999         tb_service_debugfs_remove(svc);
1000         ida_simple_remove(&xd->service_ids, svc->id);
1001         kfree(svc->key);
1002         kfree(svc);
1003 }
1004
1005 struct device_type tb_service_type = {
1006         .name = "thunderbolt_service",
1007         .groups = tb_service_attr_groups,
1008         .uevent = tb_service_uevent,
1009         .release = tb_service_release,
1010 };
1011 EXPORT_SYMBOL_GPL(tb_service_type);
1012
1013 static int remove_missing_service(struct device *dev, void *data)
1014 {
1015         struct tb_xdomain *xd = data;
1016         struct tb_service *svc;
1017
1018         svc = tb_to_service(dev);
1019         if (!svc)
1020                 return 0;
1021
1022         if (!tb_property_find(xd->remote_properties, svc->key,
1023                               TB_PROPERTY_TYPE_DIRECTORY))
1024                 device_unregister(dev);
1025
1026         return 0;
1027 }
1028
1029 static int find_service(struct device *dev, void *data)
1030 {
1031         const struct tb_property *p = data;
1032         struct tb_service *svc;
1033
1034         svc = tb_to_service(dev);
1035         if (!svc)
1036                 return 0;
1037
1038         return !strcmp(svc->key, p->key);
1039 }
1040
1041 static int populate_service(struct tb_service *svc,
1042                             struct tb_property *property)
1043 {
1044         struct tb_property_dir *dir = property->value.dir;
1045         struct tb_property *p;
1046
1047         /* Fill in standard properties */
1048         p = tb_property_find(dir, "prtcid", TB_PROPERTY_TYPE_VALUE);
1049         if (p)
1050                 svc->prtcid = p->value.immediate;
1051         p = tb_property_find(dir, "prtcvers", TB_PROPERTY_TYPE_VALUE);
1052         if (p)
1053                 svc->prtcvers = p->value.immediate;
1054         p = tb_property_find(dir, "prtcrevs", TB_PROPERTY_TYPE_VALUE);
1055         if (p)
1056                 svc->prtcrevs = p->value.immediate;
1057         p = tb_property_find(dir, "prtcstns", TB_PROPERTY_TYPE_VALUE);
1058         if (p)
1059                 svc->prtcstns = p->value.immediate;
1060
1061         svc->key = kstrdup(property->key, GFP_KERNEL);
1062         if (!svc->key)
1063                 return -ENOMEM;
1064
1065         return 0;
1066 }
1067
1068 static void enumerate_services(struct tb_xdomain *xd)
1069 {
1070         struct tb_service *svc;
1071         struct tb_property *p;
1072         struct device *dev;
1073         int id;
1074
1075         /*
1076          * First remove all services that are not available anymore in
1077          * the updated property block.
1078          */
1079         device_for_each_child_reverse(&xd->dev, xd, remove_missing_service);
1080
1081         /* Then re-enumerate properties creating new services as we go */
1082         tb_property_for_each(xd->remote_properties, p) {
1083                 if (p->type != TB_PROPERTY_TYPE_DIRECTORY)
1084                         continue;
1085
1086                 /* If the service exists already we are fine */
1087                 dev = device_find_child(&xd->dev, p, find_service);
1088                 if (dev) {
1089                         put_device(dev);
1090                         continue;
1091                 }
1092
1093                 svc = kzalloc(sizeof(*svc), GFP_KERNEL);
1094                 if (!svc)
1095                         break;
1096
1097                 if (populate_service(svc, p)) {
1098                         kfree(svc);
1099                         break;
1100                 }
1101
1102                 id = ida_simple_get(&xd->service_ids, 0, 0, GFP_KERNEL);
1103                 if (id < 0) {
1104                         kfree(svc->key);
1105                         kfree(svc);
1106                         break;
1107                 }
1108                 svc->id = id;
1109                 svc->dev.bus = &tb_bus_type;
1110                 svc->dev.type = &tb_service_type;
1111                 svc->dev.parent = &xd->dev;
1112                 dev_set_name(&svc->dev, "%s.%d", dev_name(&xd->dev), svc->id);
1113
1114                 tb_service_debugfs_init(svc);
1115
1116                 if (device_register(&svc->dev)) {
1117                         put_device(&svc->dev);
1118                         break;
1119                 }
1120         }
1121 }
1122
1123 static int populate_properties(struct tb_xdomain *xd,
1124                                struct tb_property_dir *dir)
1125 {
1126         const struct tb_property *p;
1127
1128         /* Required properties */
1129         p = tb_property_find(dir, "deviceid", TB_PROPERTY_TYPE_VALUE);
1130         if (!p)
1131                 return -EINVAL;
1132         xd->device = p->value.immediate;
1133
1134         p = tb_property_find(dir, "vendorid", TB_PROPERTY_TYPE_VALUE);
1135         if (!p)
1136                 return -EINVAL;
1137         xd->vendor = p->value.immediate;
1138
1139         p = tb_property_find(dir, "maxhopid", TB_PROPERTY_TYPE_VALUE);
1140         /*
1141          * USB4 inter-domain spec suggests using 15 as HopID if the
1142          * other end does not announce it in a property. This is for
1143          * TBT3 compatibility.
1144          */
1145         xd->remote_max_hopid = p ? p->value.immediate : XDOMAIN_DEFAULT_MAX_HOPID;
1146
1147         kfree(xd->device_name);
1148         xd->device_name = NULL;
1149         kfree(xd->vendor_name);
1150         xd->vendor_name = NULL;
1151
1152         /* Optional properties */
1153         p = tb_property_find(dir, "deviceid", TB_PROPERTY_TYPE_TEXT);
1154         if (p)
1155                 xd->device_name = kstrdup(p->value.text, GFP_KERNEL);
1156         p = tb_property_find(dir, "vendorid", TB_PROPERTY_TYPE_TEXT);
1157         if (p)
1158                 xd->vendor_name = kstrdup(p->value.text, GFP_KERNEL);
1159
1160         return 0;
1161 }
1162
1163 static int tb_xdomain_update_link_attributes(struct tb_xdomain *xd)
1164 {
1165         bool change = false;
1166         struct tb_port *port;
1167         int ret;
1168
1169         port = tb_xdomain_downstream_port(xd);
1170
1171         ret = tb_port_get_link_speed(port);
1172         if (ret < 0)
1173                 return ret;
1174
1175         if (xd->link_speed != ret)
1176                 change = true;
1177
1178         xd->link_speed = ret;
1179
1180         ret = tb_port_get_link_width(port);
1181         if (ret < 0)
1182                 return ret;
1183
1184         if (xd->link_width != ret)
1185                 change = true;
1186
1187         xd->link_width = ret;
1188
1189         if (change)
1190                 kobject_uevent(&xd->dev.kobj, KOBJ_CHANGE);
1191
1192         return 0;
1193 }
1194
1195 static int tb_xdomain_get_uuid(struct tb_xdomain *xd)
1196 {
1197         struct tb *tb = xd->tb;
1198         uuid_t uuid;
1199         u64 route;
1200         int ret;
1201
1202         dev_dbg(&xd->dev, "requesting remote UUID\n");
1203
1204         ret = tb_xdp_uuid_request(tb->ctl, xd->route, xd->state_retries, &uuid,
1205                                   &route);
1206         if (ret < 0) {
1207                 if (xd->state_retries-- > 0) {
1208                         dev_dbg(&xd->dev, "failed to request UUID, retrying\n");
1209                         return -EAGAIN;
1210                 }
1211                 dev_dbg(&xd->dev, "failed to read remote UUID\n");
1212                 return ret;
1213         }
1214
1215         dev_dbg(&xd->dev, "got remote UUID %pUb\n", &uuid);
1216
1217         if (uuid_equal(&uuid, xd->local_uuid)) {
1218                 if (route == xd->route)
1219                         dev_dbg(&xd->dev, "loop back detected\n");
1220                 else
1221                         dev_dbg(&xd->dev, "intra-domain loop detected\n");
1222
1223                 /* Don't bond lanes automatically for loops */
1224                 xd->bonding_possible = false;
1225         }
1226
1227         /*
1228          * If the UUID is different, there is another domain connected
1229          * so mark this one unplugged and wait for the connection
1230          * manager to replace it.
1231          */
1232         if (xd->remote_uuid && !uuid_equal(&uuid, xd->remote_uuid)) {
1233                 dev_dbg(&xd->dev, "remote UUID is different, unplugging\n");
1234                 xd->is_unplugged = true;
1235                 return -ENODEV;
1236         }
1237
1238         /* First time fill in the missing UUID */
1239         if (!xd->remote_uuid) {
1240                 xd->remote_uuid = kmemdup(&uuid, sizeof(uuid_t), GFP_KERNEL);
1241                 if (!xd->remote_uuid)
1242                         return -ENOMEM;
1243         }
1244
1245         return 0;
1246 }
1247
1248 static int tb_xdomain_get_link_status(struct tb_xdomain *xd)
1249 {
1250         struct tb *tb = xd->tb;
1251         u8 slw, tlw, sls, tls;
1252         int ret;
1253
1254         dev_dbg(&xd->dev, "sending link state status request to %pUb\n",
1255                 xd->remote_uuid);
1256
1257         ret = tb_xdp_link_state_status_request(tb->ctl, xd->route,
1258                                                xd->state_retries, &slw, &tlw, &sls,
1259                                                &tls);
1260         if (ret) {
1261                 if (ret != -EOPNOTSUPP && xd->state_retries-- > 0) {
1262                         dev_dbg(&xd->dev,
1263                                 "failed to request remote link status, retrying\n");
1264                         return -EAGAIN;
1265                 }
1266                 dev_dbg(&xd->dev, "failed to receive remote link status\n");
1267                 return ret;
1268         }
1269
1270         dev_dbg(&xd->dev, "remote link supports width %#x speed %#x\n", slw, sls);
1271
1272         if (slw < LANE_ADP_CS_0_SUPPORTED_WIDTH_DUAL) {
1273                 dev_dbg(&xd->dev, "remote adapter is single lane only\n");
1274                 return -EOPNOTSUPP;
1275         }
1276
1277         return 0;
1278 }
1279
1280 static int tb_xdomain_link_state_change(struct tb_xdomain *xd,
1281                                         unsigned int width)
1282 {
1283         struct tb_port *port = tb_xdomain_downstream_port(xd);
1284         struct tb *tb = xd->tb;
1285         u8 tlw, tls;
1286         u32 val;
1287         int ret;
1288
1289         if (width == 2)
1290                 tlw = LANE_ADP_CS_1_TARGET_WIDTH_DUAL;
1291         else if (width == 1)
1292                 tlw = LANE_ADP_CS_1_TARGET_WIDTH_SINGLE;
1293         else
1294                 return -EINVAL;
1295
1296         /* Use the current target speed */
1297         ret = tb_port_read(port, &val, TB_CFG_PORT, port->cap_phy + LANE_ADP_CS_1, 1);
1298         if (ret)
1299                 return ret;
1300         tls = val & LANE_ADP_CS_1_TARGET_SPEED_MASK;
1301
1302         dev_dbg(&xd->dev, "sending link state change request with width %#x speed %#x\n",
1303                 tlw, tls);
1304
1305         ret = tb_xdp_link_state_change_request(tb->ctl, xd->route,
1306                                                xd->state_retries, tlw, tls);
1307         if (ret) {
1308                 if (ret != -EOPNOTSUPP && xd->state_retries-- > 0) {
1309                         dev_dbg(&xd->dev,
1310                                 "failed to change remote link state, retrying\n");
1311                         return -EAGAIN;
1312                 }
1313                 dev_err(&xd->dev, "failed request link state change, aborting\n");
1314                 return ret;
1315         }
1316
1317         dev_dbg(&xd->dev, "received link state change response\n");
1318         return 0;
1319 }
1320
1321 static int tb_xdomain_bond_lanes_uuid_high(struct tb_xdomain *xd)
1322 {
1323         unsigned int width, width_mask;
1324         struct tb_port *port;
1325         int ret;
1326
1327         if (xd->target_link_width == LANE_ADP_CS_1_TARGET_WIDTH_SINGLE) {
1328                 width = TB_LINK_WIDTH_SINGLE;
1329                 width_mask = width;
1330         } else if (xd->target_link_width == LANE_ADP_CS_1_TARGET_WIDTH_DUAL) {
1331                 width = TB_LINK_WIDTH_DUAL;
1332                 width_mask = width | TB_LINK_WIDTH_ASYM_TX | TB_LINK_WIDTH_ASYM_RX;
1333         } else {
1334                 if (xd->state_retries-- > 0) {
1335                         dev_dbg(&xd->dev,
1336                                 "link state change request not received yet, retrying\n");
1337                         return -EAGAIN;
1338                 }
1339                 dev_dbg(&xd->dev, "timeout waiting for link change request\n");
1340                 return -ETIMEDOUT;
1341         }
1342
1343         port = tb_xdomain_downstream_port(xd);
1344
1345         /*
1346          * We can't use tb_xdomain_lane_bonding_enable() here because it
1347          * is the other side that initiates lane bonding. So here we
1348          * just set the width to both lane adapters and wait for the
1349          * link to transition bonded.
1350          */
1351         ret = tb_port_set_link_width(port->dual_link_port, width);
1352         if (ret) {
1353                 tb_port_warn(port->dual_link_port,
1354                              "failed to set link width to %d\n", width);
1355                 return ret;
1356         }
1357
1358         ret = tb_port_set_link_width(port, width);
1359         if (ret) {
1360                 tb_port_warn(port, "failed to set link width to %d\n", width);
1361                 return ret;
1362         }
1363
1364         ret = tb_port_wait_for_link_width(port, width_mask,
1365                                           XDOMAIN_BONDING_TIMEOUT);
1366         if (ret) {
1367                 dev_warn(&xd->dev, "error waiting for link width to become %d\n",
1368                          width_mask);
1369                 return ret;
1370         }
1371
1372         port->bonded = width > TB_LINK_WIDTH_SINGLE;
1373         port->dual_link_port->bonded = width > TB_LINK_WIDTH_SINGLE;
1374
1375         tb_port_update_credits(port);
1376         tb_xdomain_update_link_attributes(xd);
1377
1378         dev_dbg(&xd->dev, "lane bonding %s\n", str_enabled_disabled(width == 2));
1379         return 0;
1380 }
1381
1382 static int tb_xdomain_get_properties(struct tb_xdomain *xd)
1383 {
1384         struct tb_property_dir *dir;
1385         struct tb *tb = xd->tb;
1386         bool update = false;
1387         u32 *block = NULL;
1388         u32 gen = 0;
1389         int ret;
1390
1391         dev_dbg(&xd->dev, "requesting remote properties\n");
1392
1393         ret = tb_xdp_properties_request(tb->ctl, xd->route, xd->local_uuid,
1394                                         xd->remote_uuid, xd->state_retries,
1395                                         &block, &gen);
1396         if (ret < 0) {
1397                 if (xd->state_retries-- > 0) {
1398                         dev_dbg(&xd->dev,
1399                                 "failed to request remote properties, retrying\n");
1400                         return -EAGAIN;
1401                 }
1402                 /* Give up now */
1403                 dev_err(&xd->dev, "failed read XDomain properties from %pUb\n",
1404                         xd->remote_uuid);
1405
1406                 return ret;
1407         }
1408
1409         mutex_lock(&xd->lock);
1410
1411         /* Only accept newer generation properties */
1412         if (xd->remote_properties && gen <= xd->remote_property_block_gen) {
1413                 ret = 0;
1414                 goto err_free_block;
1415         }
1416
1417         dir = tb_property_parse_dir(block, ret);
1418         if (!dir) {
1419                 dev_err(&xd->dev, "failed to parse XDomain properties\n");
1420                 ret = -ENOMEM;
1421                 goto err_free_block;
1422         }
1423
1424         ret = populate_properties(xd, dir);
1425         if (ret) {
1426                 dev_err(&xd->dev, "missing XDomain properties in response\n");
1427                 goto err_free_dir;
1428         }
1429
1430         /* Release the existing one */
1431         if (xd->remote_properties) {
1432                 tb_property_free_dir(xd->remote_properties);
1433                 update = true;
1434         }
1435
1436         xd->remote_properties = dir;
1437         xd->remote_property_block_gen = gen;
1438
1439         tb_xdomain_update_link_attributes(xd);
1440
1441         mutex_unlock(&xd->lock);
1442
1443         kfree(block);
1444
1445         /*
1446          * Now the device should be ready enough so we can add it to the
1447          * bus and let userspace know about it. If the device is already
1448          * registered, we notify the userspace that it has changed.
1449          */
1450         if (!update) {
1451                 /*
1452                  * Now disable lane 1 if bonding was not enabled. Do
1453                  * this only if bonding was possible at the beginning
1454                  * (that is we are the connection manager and there are
1455                  * two lanes).
1456                  */
1457                 if (xd->bonding_possible) {
1458                         struct tb_port *port;
1459
1460                         port = tb_xdomain_downstream_port(xd);
1461                         if (!port->bonded)
1462                                 tb_port_disable(port->dual_link_port);
1463                 }
1464
1465                 if (device_add(&xd->dev)) {
1466                         dev_err(&xd->dev, "failed to add XDomain device\n");
1467                         return -ENODEV;
1468                 }
1469                 dev_info(&xd->dev, "new host found, vendor=%#x device=%#x\n",
1470                          xd->vendor, xd->device);
1471                 if (xd->vendor_name && xd->device_name)
1472                         dev_info(&xd->dev, "%s %s\n", xd->vendor_name,
1473                                  xd->device_name);
1474
1475                 tb_xdomain_debugfs_init(xd);
1476         } else {
1477                 kobject_uevent(&xd->dev.kobj, KOBJ_CHANGE);
1478         }
1479
1480         enumerate_services(xd);
1481         return 0;
1482
1483 err_free_dir:
1484         tb_property_free_dir(dir);
1485 err_free_block:
1486         kfree(block);
1487         mutex_unlock(&xd->lock);
1488
1489         return ret;
1490 }
1491
1492 static void tb_xdomain_queue_uuid(struct tb_xdomain *xd)
1493 {
1494         xd->state = XDOMAIN_STATE_UUID;
1495         xd->state_retries = XDOMAIN_RETRIES;
1496         queue_delayed_work(xd->tb->wq, &xd->state_work,
1497                            msecs_to_jiffies(XDOMAIN_SHORT_TIMEOUT));
1498 }
1499
1500 static void tb_xdomain_queue_link_status(struct tb_xdomain *xd)
1501 {
1502         xd->state = XDOMAIN_STATE_LINK_STATUS;
1503         xd->state_retries = XDOMAIN_RETRIES;
1504         queue_delayed_work(xd->tb->wq, &xd->state_work,
1505                            msecs_to_jiffies(XDOMAIN_DEFAULT_TIMEOUT));
1506 }
1507
1508 static void tb_xdomain_queue_link_status2(struct tb_xdomain *xd)
1509 {
1510         xd->state = XDOMAIN_STATE_LINK_STATUS2;
1511         xd->state_retries = XDOMAIN_RETRIES;
1512         queue_delayed_work(xd->tb->wq, &xd->state_work,
1513                            msecs_to_jiffies(XDOMAIN_DEFAULT_TIMEOUT));
1514 }
1515
1516 static void tb_xdomain_queue_bonding(struct tb_xdomain *xd)
1517 {
1518         if (memcmp(xd->local_uuid, xd->remote_uuid, UUID_SIZE) > 0) {
1519                 dev_dbg(&xd->dev, "we have higher UUID, other side bonds the lanes\n");
1520                 xd->state = XDOMAIN_STATE_BONDING_UUID_HIGH;
1521         } else {
1522                 dev_dbg(&xd->dev, "we have lower UUID, bonding lanes\n");
1523                 xd->state = XDOMAIN_STATE_LINK_STATE_CHANGE;
1524         }
1525
1526         xd->state_retries = XDOMAIN_RETRIES;
1527         queue_delayed_work(xd->tb->wq, &xd->state_work,
1528                            msecs_to_jiffies(XDOMAIN_DEFAULT_TIMEOUT));
1529 }
1530
1531 static void tb_xdomain_queue_bonding_uuid_low(struct tb_xdomain *xd)
1532 {
1533         xd->state = XDOMAIN_STATE_BONDING_UUID_LOW;
1534         xd->state_retries = XDOMAIN_RETRIES;
1535         queue_delayed_work(xd->tb->wq, &xd->state_work,
1536                            msecs_to_jiffies(XDOMAIN_DEFAULT_TIMEOUT));
1537 }
1538
1539 static void tb_xdomain_queue_properties(struct tb_xdomain *xd)
1540 {
1541         xd->state = XDOMAIN_STATE_PROPERTIES;
1542         xd->state_retries = XDOMAIN_RETRIES;
1543         queue_delayed_work(xd->tb->wq, &xd->state_work,
1544                            msecs_to_jiffies(XDOMAIN_DEFAULT_TIMEOUT));
1545 }
1546
1547 static void tb_xdomain_queue_properties_changed(struct tb_xdomain *xd)
1548 {
1549         xd->properties_changed_retries = XDOMAIN_RETRIES;
1550         queue_delayed_work(xd->tb->wq, &xd->properties_changed_work,
1551                            msecs_to_jiffies(XDOMAIN_SHORT_TIMEOUT));
1552 }
1553
1554 static void tb_xdomain_failed(struct tb_xdomain *xd)
1555 {
1556         xd->state = XDOMAIN_STATE_ERROR;
1557         queue_delayed_work(xd->tb->wq, &xd->state_work,
1558                            msecs_to_jiffies(XDOMAIN_DEFAULT_TIMEOUT));
1559 }
1560
1561 static void tb_xdomain_state_work(struct work_struct *work)
1562 {
1563         struct tb_xdomain *xd = container_of(work, typeof(*xd), state_work.work);
1564         int ret, state = xd->state;
1565
1566         if (WARN_ON_ONCE(state < XDOMAIN_STATE_INIT ||
1567                          state > XDOMAIN_STATE_ERROR))
1568                 return;
1569
1570         dev_dbg(&xd->dev, "running state %s\n", state_names[state]);
1571
1572         switch (state) {
1573         case XDOMAIN_STATE_INIT:
1574                 if (xd->needs_uuid) {
1575                         tb_xdomain_queue_uuid(xd);
1576                 } else {
1577                         tb_xdomain_queue_properties_changed(xd);
1578                         tb_xdomain_queue_properties(xd);
1579                 }
1580                 break;
1581
1582         case XDOMAIN_STATE_UUID:
1583                 ret = tb_xdomain_get_uuid(xd);
1584                 if (ret) {
1585                         if (ret == -EAGAIN)
1586                                 goto retry_state;
1587                         tb_xdomain_failed(xd);
1588                 } else {
1589                         tb_xdomain_queue_properties_changed(xd);
1590                         if (xd->bonding_possible)
1591                                 tb_xdomain_queue_link_status(xd);
1592                         else
1593                                 tb_xdomain_queue_properties(xd);
1594                 }
1595                 break;
1596
1597         case XDOMAIN_STATE_LINK_STATUS:
1598                 ret = tb_xdomain_get_link_status(xd);
1599                 if (ret) {
1600                         if (ret == -EAGAIN)
1601                                 goto retry_state;
1602
1603                         /*
1604                          * If any of the lane bonding states fail we skip
1605                          * bonding completely and try to continue from
1606                          * reading properties.
1607                          */
1608                         tb_xdomain_queue_properties(xd);
1609                 } else {
1610                         tb_xdomain_queue_bonding(xd);
1611                 }
1612                 break;
1613
1614         case XDOMAIN_STATE_LINK_STATE_CHANGE:
1615                 ret = tb_xdomain_link_state_change(xd, 2);
1616                 if (ret) {
1617                         if (ret == -EAGAIN)
1618                                 goto retry_state;
1619                         tb_xdomain_queue_properties(xd);
1620                 } else {
1621                         tb_xdomain_queue_link_status2(xd);
1622                 }
1623                 break;
1624
1625         case XDOMAIN_STATE_LINK_STATUS2:
1626                 ret = tb_xdomain_get_link_status(xd);
1627                 if (ret) {
1628                         if (ret == -EAGAIN)
1629                                 goto retry_state;
1630                         tb_xdomain_queue_properties(xd);
1631                 } else {
1632                         tb_xdomain_queue_bonding_uuid_low(xd);
1633                 }
1634                 break;
1635
1636         case XDOMAIN_STATE_BONDING_UUID_LOW:
1637                 tb_xdomain_lane_bonding_enable(xd);
1638                 tb_xdomain_queue_properties(xd);
1639                 break;
1640
1641         case XDOMAIN_STATE_BONDING_UUID_HIGH:
1642                 if (tb_xdomain_bond_lanes_uuid_high(xd) == -EAGAIN)
1643                         goto retry_state;
1644                 tb_xdomain_queue_properties(xd);
1645                 break;
1646
1647         case XDOMAIN_STATE_PROPERTIES:
1648                 ret = tb_xdomain_get_properties(xd);
1649                 if (ret) {
1650                         if (ret == -EAGAIN)
1651                                 goto retry_state;
1652                         tb_xdomain_failed(xd);
1653                 } else {
1654                         xd->state = XDOMAIN_STATE_ENUMERATED;
1655                 }
1656                 break;
1657
1658         case XDOMAIN_STATE_ENUMERATED:
1659                 tb_xdomain_queue_properties(xd);
1660                 break;
1661
1662         case XDOMAIN_STATE_ERROR:
1663                 dev_dbg(&xd->dev, "discovery failed, stopping handshake\n");
1664                 __stop_handshake(xd);
1665                 break;
1666
1667         default:
1668                 dev_warn(&xd->dev, "unexpected state %d\n", state);
1669                 break;
1670         }
1671
1672         return;
1673
1674 retry_state:
1675         queue_delayed_work(xd->tb->wq, &xd->state_work,
1676                            msecs_to_jiffies(XDOMAIN_DEFAULT_TIMEOUT));
1677 }
1678
1679 static void tb_xdomain_properties_changed(struct work_struct *work)
1680 {
1681         struct tb_xdomain *xd = container_of(work, typeof(*xd),
1682                                              properties_changed_work.work);
1683         int ret;
1684
1685         dev_dbg(&xd->dev, "sending properties changed notification\n");
1686
1687         ret = tb_xdp_properties_changed_request(xd->tb->ctl, xd->route,
1688                                 xd->properties_changed_retries, xd->local_uuid);
1689         if (ret) {
1690                 if (xd->properties_changed_retries-- > 0) {
1691                         dev_dbg(&xd->dev,
1692                                 "failed to send properties changed notification, retrying\n");
1693                         queue_delayed_work(xd->tb->wq,
1694                                            &xd->properties_changed_work,
1695                                            msecs_to_jiffies(XDOMAIN_DEFAULT_TIMEOUT));
1696                 }
1697                 dev_err(&xd->dev, "failed to send properties changed notification\n");
1698                 return;
1699         }
1700
1701         xd->properties_changed_retries = XDOMAIN_RETRIES;
1702 }
1703
1704 static ssize_t device_show(struct device *dev, struct device_attribute *attr,
1705                            char *buf)
1706 {
1707         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1708
1709         return sysfs_emit(buf, "%#x\n", xd->device);
1710 }
1711 static DEVICE_ATTR_RO(device);
1712
1713 static ssize_t
1714 device_name_show(struct device *dev, struct device_attribute *attr, char *buf)
1715 {
1716         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1717         int ret;
1718
1719         if (mutex_lock_interruptible(&xd->lock))
1720                 return -ERESTARTSYS;
1721         ret = sysfs_emit(buf, "%s\n", xd->device_name ?: "");
1722         mutex_unlock(&xd->lock);
1723
1724         return ret;
1725 }
1726 static DEVICE_ATTR_RO(device_name);
1727
1728 static ssize_t maxhopid_show(struct device *dev, struct device_attribute *attr,
1729                              char *buf)
1730 {
1731         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1732
1733         return sysfs_emit(buf, "%d\n", xd->remote_max_hopid);
1734 }
1735 static DEVICE_ATTR_RO(maxhopid);
1736
1737 static ssize_t vendor_show(struct device *dev, struct device_attribute *attr,
1738                            char *buf)
1739 {
1740         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1741
1742         return sysfs_emit(buf, "%#x\n", xd->vendor);
1743 }
1744 static DEVICE_ATTR_RO(vendor);
1745
1746 static ssize_t
1747 vendor_name_show(struct device *dev, struct device_attribute *attr, char *buf)
1748 {
1749         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1750         int ret;
1751
1752         if (mutex_lock_interruptible(&xd->lock))
1753                 return -ERESTARTSYS;
1754         ret = sysfs_emit(buf, "%s\n", xd->vendor_name ?: "");
1755         mutex_unlock(&xd->lock);
1756
1757         return ret;
1758 }
1759 static DEVICE_ATTR_RO(vendor_name);
1760
1761 static ssize_t unique_id_show(struct device *dev, struct device_attribute *attr,
1762                               char *buf)
1763 {
1764         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1765
1766         return sysfs_emit(buf, "%pUb\n", xd->remote_uuid);
1767 }
1768 static DEVICE_ATTR_RO(unique_id);
1769
1770 static ssize_t speed_show(struct device *dev, struct device_attribute *attr,
1771                           char *buf)
1772 {
1773         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1774
1775         return sysfs_emit(buf, "%u.0 Gb/s\n", xd->link_speed);
1776 }
1777
1778 static DEVICE_ATTR(rx_speed, 0444, speed_show, NULL);
1779 static DEVICE_ATTR(tx_speed, 0444, speed_show, NULL);
1780
1781 static ssize_t rx_lanes_show(struct device *dev, struct device_attribute *attr,
1782                              char *buf)
1783 {
1784         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1785         unsigned int width;
1786
1787         switch (xd->link_width) {
1788         case TB_LINK_WIDTH_SINGLE:
1789         case TB_LINK_WIDTH_ASYM_RX:
1790                 width = 1;
1791                 break;
1792         case TB_LINK_WIDTH_DUAL:
1793                 width = 2;
1794                 break;
1795         case TB_LINK_WIDTH_ASYM_TX:
1796                 width = 3;
1797                 break;
1798         default:
1799                 WARN_ON_ONCE(1);
1800                 return -EINVAL;
1801         }
1802
1803         return sysfs_emit(buf, "%u\n", width);
1804 }
1805 static DEVICE_ATTR(rx_lanes, 0444, rx_lanes_show, NULL);
1806
1807 static ssize_t tx_lanes_show(struct device *dev, struct device_attribute *attr,
1808                              char *buf)
1809 {
1810         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1811         unsigned int width;
1812
1813         switch (xd->link_width) {
1814         case TB_LINK_WIDTH_SINGLE:
1815         case TB_LINK_WIDTH_ASYM_TX:
1816                 width = 1;
1817                 break;
1818         case TB_LINK_WIDTH_DUAL:
1819                 width = 2;
1820                 break;
1821         case TB_LINK_WIDTH_ASYM_RX:
1822                 width = 3;
1823                 break;
1824         default:
1825                 WARN_ON_ONCE(1);
1826                 return -EINVAL;
1827         }
1828
1829         return sysfs_emit(buf, "%u\n", width);
1830 }
1831 static DEVICE_ATTR(tx_lanes, 0444, tx_lanes_show, NULL);
1832
1833 static struct attribute *xdomain_attrs[] = {
1834         &dev_attr_device.attr,
1835         &dev_attr_device_name.attr,
1836         &dev_attr_maxhopid.attr,
1837         &dev_attr_rx_lanes.attr,
1838         &dev_attr_rx_speed.attr,
1839         &dev_attr_tx_lanes.attr,
1840         &dev_attr_tx_speed.attr,
1841         &dev_attr_unique_id.attr,
1842         &dev_attr_vendor.attr,
1843         &dev_attr_vendor_name.attr,
1844         NULL,
1845 };
1846
1847 static const struct attribute_group xdomain_attr_group = {
1848         .attrs = xdomain_attrs,
1849 };
1850
1851 static const struct attribute_group *xdomain_attr_groups[] = {
1852         &xdomain_attr_group,
1853         NULL,
1854 };
1855
1856 static void tb_xdomain_release(struct device *dev)
1857 {
1858         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1859
1860         put_device(xd->dev.parent);
1861
1862         kfree(xd->local_property_block);
1863         tb_property_free_dir(xd->remote_properties);
1864         ida_destroy(&xd->out_hopids);
1865         ida_destroy(&xd->in_hopids);
1866         ida_destroy(&xd->service_ids);
1867
1868         kfree(xd->local_uuid);
1869         kfree(xd->remote_uuid);
1870         kfree(xd->device_name);
1871         kfree(xd->vendor_name);
1872         kfree(xd);
1873 }
1874
1875 static int __maybe_unused tb_xdomain_suspend(struct device *dev)
1876 {
1877         stop_handshake(tb_to_xdomain(dev));
1878         return 0;
1879 }
1880
1881 static int __maybe_unused tb_xdomain_resume(struct device *dev)
1882 {
1883         start_handshake(tb_to_xdomain(dev));
1884         return 0;
1885 }
1886
1887 static const struct dev_pm_ops tb_xdomain_pm_ops = {
1888         SET_SYSTEM_SLEEP_PM_OPS(tb_xdomain_suspend, tb_xdomain_resume)
1889 };
1890
1891 struct device_type tb_xdomain_type = {
1892         .name = "thunderbolt_xdomain",
1893         .release = tb_xdomain_release,
1894         .pm = &tb_xdomain_pm_ops,
1895 };
1896 EXPORT_SYMBOL_GPL(tb_xdomain_type);
1897
1898 /**
1899  * tb_xdomain_alloc() - Allocate new XDomain object
1900  * @tb: Domain where the XDomain belongs
1901  * @parent: Parent device (the switch through the connection to the
1902  *          other domain is reached).
1903  * @route: Route string used to reach the other domain
1904  * @local_uuid: Our local domain UUID
1905  * @remote_uuid: UUID of the other domain (optional)
1906  *
1907  * Allocates new XDomain structure and returns pointer to that. The
1908  * object must be released by calling tb_xdomain_put().
1909  */
1910 struct tb_xdomain *tb_xdomain_alloc(struct tb *tb, struct device *parent,
1911                                     u64 route, const uuid_t *local_uuid,
1912                                     const uuid_t *remote_uuid)
1913 {
1914         struct tb_switch *parent_sw = tb_to_switch(parent);
1915         struct tb_xdomain *xd;
1916         struct tb_port *down;
1917
1918         /* Make sure the downstream domain is accessible */
1919         down = tb_port_at(route, parent_sw);
1920         tb_port_unlock(down);
1921
1922         xd = kzalloc(sizeof(*xd), GFP_KERNEL);
1923         if (!xd)
1924                 return NULL;
1925
1926         xd->tb = tb;
1927         xd->route = route;
1928         xd->local_max_hopid = down->config.max_in_hop_id;
1929         ida_init(&xd->service_ids);
1930         ida_init(&xd->in_hopids);
1931         ida_init(&xd->out_hopids);
1932         mutex_init(&xd->lock);
1933         INIT_DELAYED_WORK(&xd->state_work, tb_xdomain_state_work);
1934         INIT_DELAYED_WORK(&xd->properties_changed_work,
1935                           tb_xdomain_properties_changed);
1936
1937         xd->local_uuid = kmemdup(local_uuid, sizeof(uuid_t), GFP_KERNEL);
1938         if (!xd->local_uuid)
1939                 goto err_free;
1940
1941         if (remote_uuid) {
1942                 xd->remote_uuid = kmemdup(remote_uuid, sizeof(uuid_t),
1943                                           GFP_KERNEL);
1944                 if (!xd->remote_uuid)
1945                         goto err_free_local_uuid;
1946         } else {
1947                 xd->needs_uuid = true;
1948                 xd->bonding_possible = !!down->dual_link_port;
1949         }
1950
1951         device_initialize(&xd->dev);
1952         xd->dev.parent = get_device(parent);
1953         xd->dev.bus = &tb_bus_type;
1954         xd->dev.type = &tb_xdomain_type;
1955         xd->dev.groups = xdomain_attr_groups;
1956         dev_set_name(&xd->dev, "%u-%llx", tb->index, route);
1957
1958         dev_dbg(&xd->dev, "local UUID %pUb\n", local_uuid);
1959         if (remote_uuid)
1960                 dev_dbg(&xd->dev, "remote UUID %pUb\n", remote_uuid);
1961
1962         /*
1963          * This keeps the DMA powered on as long as we have active
1964          * connection to another host.
1965          */
1966         pm_runtime_set_active(&xd->dev);
1967         pm_runtime_get_noresume(&xd->dev);
1968         pm_runtime_enable(&xd->dev);
1969
1970         return xd;
1971
1972 err_free_local_uuid:
1973         kfree(xd->local_uuid);
1974 err_free:
1975         kfree(xd);
1976
1977         return NULL;
1978 }
1979
1980 /**
1981  * tb_xdomain_add() - Add XDomain to the bus
1982  * @xd: XDomain to add
1983  *
1984  * This function starts XDomain discovery protocol handshake and
1985  * eventually adds the XDomain to the bus. After calling this function
1986  * the caller needs to call tb_xdomain_remove() in order to remove and
1987  * release the object regardless whether the handshake succeeded or not.
1988  */
1989 void tb_xdomain_add(struct tb_xdomain *xd)
1990 {
1991         /* Start exchanging properties with the other host */
1992         start_handshake(xd);
1993 }
1994
1995 static int unregister_service(struct device *dev, void *data)
1996 {
1997         device_unregister(dev);
1998         return 0;
1999 }
2000
2001 /**
2002  * tb_xdomain_remove() - Remove XDomain from the bus
2003  * @xd: XDomain to remove
2004  *
2005  * This will stop all ongoing configuration work and remove the XDomain
2006  * along with any services from the bus. When the last reference to @xd
2007  * is released the object will be released as well.
2008  */
2009 void tb_xdomain_remove(struct tb_xdomain *xd)
2010 {
2011         tb_xdomain_debugfs_remove(xd);
2012
2013         stop_handshake(xd);
2014
2015         device_for_each_child_reverse(&xd->dev, xd, unregister_service);
2016
2017         /*
2018          * Undo runtime PM here explicitly because it is possible that
2019          * the XDomain was never added to the bus and thus device_del()
2020          * is not called for it (device_del() would handle this otherwise).
2021          */
2022         pm_runtime_disable(&xd->dev);
2023         pm_runtime_put_noidle(&xd->dev);
2024         pm_runtime_set_suspended(&xd->dev);
2025
2026         if (!device_is_registered(&xd->dev)) {
2027                 put_device(&xd->dev);
2028         } else {
2029                 dev_info(&xd->dev, "host disconnected\n");
2030                 device_unregister(&xd->dev);
2031         }
2032 }
2033
2034 /**
2035  * tb_xdomain_lane_bonding_enable() - Enable lane bonding on XDomain
2036  * @xd: XDomain connection
2037  *
2038  * Lane bonding is disabled by default for XDomains. This function tries
2039  * to enable bonding by first enabling the port and waiting for the CL0
2040  * state.
2041  *
2042  * Return: %0 in case of success and negative errno in case of error.
2043  */
2044 int tb_xdomain_lane_bonding_enable(struct tb_xdomain *xd)
2045 {
2046         unsigned int width_mask;
2047         struct tb_port *port;
2048         int ret;
2049
2050         port = tb_xdomain_downstream_port(xd);
2051         if (!port->dual_link_port)
2052                 return -ENODEV;
2053
2054         ret = tb_port_enable(port->dual_link_port);
2055         if (ret)
2056                 return ret;
2057
2058         ret = tb_wait_for_port(port->dual_link_port, true);
2059         if (ret < 0)
2060                 return ret;
2061         if (!ret)
2062                 return -ENOTCONN;
2063
2064         ret = tb_port_lane_bonding_enable(port);
2065         if (ret) {
2066                 tb_port_warn(port, "failed to enable lane bonding\n");
2067                 return ret;
2068         }
2069
2070         /* Any of the widths are all bonded */
2071         width_mask = TB_LINK_WIDTH_DUAL | TB_LINK_WIDTH_ASYM_TX |
2072                      TB_LINK_WIDTH_ASYM_RX;
2073
2074         ret = tb_port_wait_for_link_width(port, width_mask,
2075                                           XDOMAIN_BONDING_TIMEOUT);
2076         if (ret) {
2077                 tb_port_warn(port, "failed to enable lane bonding\n");
2078                 return ret;
2079         }
2080
2081         tb_port_update_credits(port);
2082         tb_xdomain_update_link_attributes(xd);
2083
2084         dev_dbg(&xd->dev, "lane bonding enabled\n");
2085         return 0;
2086 }
2087 EXPORT_SYMBOL_GPL(tb_xdomain_lane_bonding_enable);
2088
2089 /**
2090  * tb_xdomain_lane_bonding_disable() - Disable lane bonding
2091  * @xd: XDomain connection
2092  *
2093  * Lane bonding is disabled by default for XDomains. If bonding has been
2094  * enabled, this function can be used to disable it.
2095  */
2096 void tb_xdomain_lane_bonding_disable(struct tb_xdomain *xd)
2097 {
2098         struct tb_port *port;
2099
2100         port = tb_xdomain_downstream_port(xd);
2101         if (port->dual_link_port) {
2102                 int ret;
2103
2104                 tb_port_lane_bonding_disable(port);
2105                 ret = tb_port_wait_for_link_width(port, TB_LINK_WIDTH_SINGLE, 100);
2106                 if (ret == -ETIMEDOUT)
2107                         tb_port_warn(port, "timeout disabling lane bonding\n");
2108                 tb_port_disable(port->dual_link_port);
2109                 tb_port_update_credits(port);
2110                 tb_xdomain_update_link_attributes(xd);
2111
2112                 dev_dbg(&xd->dev, "lane bonding disabled\n");
2113         }
2114 }
2115 EXPORT_SYMBOL_GPL(tb_xdomain_lane_bonding_disable);
2116
2117 /**
2118  * tb_xdomain_alloc_in_hopid() - Allocate input HopID for tunneling
2119  * @xd: XDomain connection
2120  * @hopid: Preferred HopID or %-1 for next available
2121  *
2122  * Returns allocated HopID or negative errno. Specifically returns
2123  * %-ENOSPC if there are no more available HopIDs. Returned HopID is
2124  * guaranteed to be within range supported by the input lane adapter.
2125  * Call tb_xdomain_release_in_hopid() to release the allocated HopID.
2126  */
2127 int tb_xdomain_alloc_in_hopid(struct tb_xdomain *xd, int hopid)
2128 {
2129         if (hopid < 0)
2130                 hopid = TB_PATH_MIN_HOPID;
2131         if (hopid < TB_PATH_MIN_HOPID || hopid > xd->local_max_hopid)
2132                 return -EINVAL;
2133
2134         return ida_alloc_range(&xd->in_hopids, hopid, xd->local_max_hopid,
2135                                GFP_KERNEL);
2136 }
2137 EXPORT_SYMBOL_GPL(tb_xdomain_alloc_in_hopid);
2138
2139 /**
2140  * tb_xdomain_alloc_out_hopid() - Allocate output HopID for tunneling
2141  * @xd: XDomain connection
2142  * @hopid: Preferred HopID or %-1 for next available
2143  *
2144  * Returns allocated HopID or negative errno. Specifically returns
2145  * %-ENOSPC if there are no more available HopIDs. Returned HopID is
2146  * guaranteed to be within range supported by the output lane adapter.
2147  * Call tb_xdomain_release_in_hopid() to release the allocated HopID.
2148  */
2149 int tb_xdomain_alloc_out_hopid(struct tb_xdomain *xd, int hopid)
2150 {
2151         if (hopid < 0)
2152                 hopid = TB_PATH_MIN_HOPID;
2153         if (hopid < TB_PATH_MIN_HOPID || hopid > xd->remote_max_hopid)
2154                 return -EINVAL;
2155
2156         return ida_alloc_range(&xd->out_hopids, hopid, xd->remote_max_hopid,
2157                                GFP_KERNEL);
2158 }
2159 EXPORT_SYMBOL_GPL(tb_xdomain_alloc_out_hopid);
2160
2161 /**
2162  * tb_xdomain_release_in_hopid() - Release input HopID
2163  * @xd: XDomain connection
2164  * @hopid: HopID to release
2165  */
2166 void tb_xdomain_release_in_hopid(struct tb_xdomain *xd, int hopid)
2167 {
2168         ida_free(&xd->in_hopids, hopid);
2169 }
2170 EXPORT_SYMBOL_GPL(tb_xdomain_release_in_hopid);
2171
2172 /**
2173  * tb_xdomain_release_out_hopid() - Release output HopID
2174  * @xd: XDomain connection
2175  * @hopid: HopID to release
2176  */
2177 void tb_xdomain_release_out_hopid(struct tb_xdomain *xd, int hopid)
2178 {
2179         ida_free(&xd->out_hopids, hopid);
2180 }
2181 EXPORT_SYMBOL_GPL(tb_xdomain_release_out_hopid);
2182
2183 /**
2184  * tb_xdomain_enable_paths() - Enable DMA paths for XDomain connection
2185  * @xd: XDomain connection
2186  * @transmit_path: HopID we are using to send out packets
2187  * @transmit_ring: DMA ring used to send out packets
2188  * @receive_path: HopID the other end is using to send packets to us
2189  * @receive_ring: DMA ring used to receive packets from @receive_path
2190  *
2191  * The function enables DMA paths accordingly so that after successful
2192  * return the caller can send and receive packets using high-speed DMA
2193  * path. If a transmit or receive path is not needed, pass %-1 for those
2194  * parameters.
2195  *
2196  * Return: %0 in case of success and negative errno in case of error
2197  */
2198 int tb_xdomain_enable_paths(struct tb_xdomain *xd, int transmit_path,
2199                             int transmit_ring, int receive_path,
2200                             int receive_ring)
2201 {
2202         return tb_domain_approve_xdomain_paths(xd->tb, xd, transmit_path,
2203                                                transmit_ring, receive_path,
2204                                                receive_ring);
2205 }
2206 EXPORT_SYMBOL_GPL(tb_xdomain_enable_paths);
2207
2208 /**
2209  * tb_xdomain_disable_paths() - Disable DMA paths for XDomain connection
2210  * @xd: XDomain connection
2211  * @transmit_path: HopID we are using to send out packets
2212  * @transmit_ring: DMA ring used to send out packets
2213  * @receive_path: HopID the other end is using to send packets to us
2214  * @receive_ring: DMA ring used to receive packets from @receive_path
2215  *
2216  * This does the opposite of tb_xdomain_enable_paths(). After call to
2217  * this the caller is not expected to use the rings anymore. Passing %-1
2218  * as path/ring parameter means don't care. Normally the callers should
2219  * pass the same values here as they do when paths are enabled.
2220  *
2221  * Return: %0 in case of success and negative errno in case of error
2222  */
2223 int tb_xdomain_disable_paths(struct tb_xdomain *xd, int transmit_path,
2224                              int transmit_ring, int receive_path,
2225                              int receive_ring)
2226 {
2227         return tb_domain_disconnect_xdomain_paths(xd->tb, xd, transmit_path,
2228                                                   transmit_ring, receive_path,
2229                                                   receive_ring);
2230 }
2231 EXPORT_SYMBOL_GPL(tb_xdomain_disable_paths);
2232
2233 struct tb_xdomain_lookup {
2234         const uuid_t *uuid;
2235         u8 link;
2236         u8 depth;
2237         u64 route;
2238 };
2239
2240 static struct tb_xdomain *switch_find_xdomain(struct tb_switch *sw,
2241         const struct tb_xdomain_lookup *lookup)
2242 {
2243         struct tb_port *port;
2244
2245         tb_switch_for_each_port(sw, port) {
2246                 struct tb_xdomain *xd;
2247
2248                 if (port->xdomain) {
2249                         xd = port->xdomain;
2250
2251                         if (lookup->uuid) {
2252                                 if (xd->remote_uuid &&
2253                                     uuid_equal(xd->remote_uuid, lookup->uuid))
2254                                         return xd;
2255                         } else {
2256                                 if (lookup->link && lookup->link == xd->link &&
2257                                     lookup->depth == xd->depth)
2258                                         return xd;
2259                                 if (lookup->route && lookup->route == xd->route)
2260                                         return xd;
2261                         }
2262                 } else if (tb_port_has_remote(port)) {
2263                         xd = switch_find_xdomain(port->remote->sw, lookup);
2264                         if (xd)
2265                                 return xd;
2266                 }
2267         }
2268
2269         return NULL;
2270 }
2271
2272 /**
2273  * tb_xdomain_find_by_uuid() - Find an XDomain by UUID
2274  * @tb: Domain where the XDomain belongs to
2275  * @uuid: UUID to look for
2276  *
2277  * Finds XDomain by walking through the Thunderbolt topology below @tb.
2278  * The returned XDomain will have its reference count increased so the
2279  * caller needs to call tb_xdomain_put() when it is done with the
2280  * object.
2281  *
2282  * This will find all XDomains including the ones that are not yet added
2283  * to the bus (handshake is still in progress).
2284  *
2285  * The caller needs to hold @tb->lock.
2286  */
2287 struct tb_xdomain *tb_xdomain_find_by_uuid(struct tb *tb, const uuid_t *uuid)
2288 {
2289         struct tb_xdomain_lookup lookup;
2290         struct tb_xdomain *xd;
2291
2292         memset(&lookup, 0, sizeof(lookup));
2293         lookup.uuid = uuid;
2294
2295         xd = switch_find_xdomain(tb->root_switch, &lookup);
2296         return tb_xdomain_get(xd);
2297 }
2298 EXPORT_SYMBOL_GPL(tb_xdomain_find_by_uuid);
2299
2300 /**
2301  * tb_xdomain_find_by_link_depth() - Find an XDomain by link and depth
2302  * @tb: Domain where the XDomain belongs to
2303  * @link: Root switch link number
2304  * @depth: Depth in the link
2305  *
2306  * Finds XDomain by walking through the Thunderbolt topology below @tb.
2307  * The returned XDomain will have its reference count increased so the
2308  * caller needs to call tb_xdomain_put() when it is done with the
2309  * object.
2310  *
2311  * This will find all XDomains including the ones that are not yet added
2312  * to the bus (handshake is still in progress).
2313  *
2314  * The caller needs to hold @tb->lock.
2315  */
2316 struct tb_xdomain *tb_xdomain_find_by_link_depth(struct tb *tb, u8 link,
2317                                                  u8 depth)
2318 {
2319         struct tb_xdomain_lookup lookup;
2320         struct tb_xdomain *xd;
2321
2322         memset(&lookup, 0, sizeof(lookup));
2323         lookup.link = link;
2324         lookup.depth = depth;
2325
2326         xd = switch_find_xdomain(tb->root_switch, &lookup);
2327         return tb_xdomain_get(xd);
2328 }
2329
2330 /**
2331  * tb_xdomain_find_by_route() - Find an XDomain by route string
2332  * @tb: Domain where the XDomain belongs to
2333  * @route: XDomain route string
2334  *
2335  * Finds XDomain by walking through the Thunderbolt topology below @tb.
2336  * The returned XDomain will have its reference count increased so the
2337  * caller needs to call tb_xdomain_put() when it is done with the
2338  * object.
2339  *
2340  * This will find all XDomains including the ones that are not yet added
2341  * to the bus (handshake is still in progress).
2342  *
2343  * The caller needs to hold @tb->lock.
2344  */
2345 struct tb_xdomain *tb_xdomain_find_by_route(struct tb *tb, u64 route)
2346 {
2347         struct tb_xdomain_lookup lookup;
2348         struct tb_xdomain *xd;
2349
2350         memset(&lookup, 0, sizeof(lookup));
2351         lookup.route = route;
2352
2353         xd = switch_find_xdomain(tb->root_switch, &lookup);
2354         return tb_xdomain_get(xd);
2355 }
2356 EXPORT_SYMBOL_GPL(tb_xdomain_find_by_route);
2357
2358 bool tb_xdomain_handle_request(struct tb *tb, enum tb_cfg_pkg_type type,
2359                                const void *buf, size_t size)
2360 {
2361         const struct tb_protocol_handler *handler, *tmp;
2362         const struct tb_xdp_header *hdr = buf;
2363         unsigned int length;
2364         int ret = 0;
2365
2366         /* We expect the packet is at least size of the header */
2367         length = hdr->xd_hdr.length_sn & TB_XDOMAIN_LENGTH_MASK;
2368         if (length != size / 4 - sizeof(hdr->xd_hdr) / 4)
2369                 return true;
2370         if (length < sizeof(*hdr) / 4 - sizeof(hdr->xd_hdr) / 4)
2371                 return true;
2372
2373         /*
2374          * Handle XDomain discovery protocol packets directly here. For
2375          * other protocols (based on their UUID) we call registered
2376          * handlers in turn.
2377          */
2378         if (uuid_equal(&hdr->uuid, &tb_xdp_uuid)) {
2379                 if (type == TB_CFG_PKG_XDOMAIN_REQ)
2380                         return tb_xdp_schedule_request(tb, hdr, size);
2381                 return false;
2382         }
2383
2384         mutex_lock(&xdomain_lock);
2385         list_for_each_entry_safe(handler, tmp, &protocol_handlers, list) {
2386                 if (!uuid_equal(&hdr->uuid, handler->uuid))
2387                         continue;
2388
2389                 mutex_unlock(&xdomain_lock);
2390                 ret = handler->callback(buf, size, handler->data);
2391                 mutex_lock(&xdomain_lock);
2392
2393                 if (ret)
2394                         break;
2395         }
2396         mutex_unlock(&xdomain_lock);
2397
2398         return ret > 0;
2399 }
2400
2401 static int update_xdomain(struct device *dev, void *data)
2402 {
2403         struct tb_xdomain *xd;
2404
2405         xd = tb_to_xdomain(dev);
2406         if (xd) {
2407                 queue_delayed_work(xd->tb->wq, &xd->properties_changed_work,
2408                                    msecs_to_jiffies(50));
2409         }
2410
2411         return 0;
2412 }
2413
2414 static void update_all_xdomains(void)
2415 {
2416         bus_for_each_dev(&tb_bus_type, NULL, NULL, update_xdomain);
2417 }
2418
2419 static bool remove_directory(const char *key, const struct tb_property_dir *dir)
2420 {
2421         struct tb_property *p;
2422
2423         p = tb_property_find(xdomain_property_dir, key,
2424                              TB_PROPERTY_TYPE_DIRECTORY);
2425         if (p && p->value.dir == dir) {
2426                 tb_property_remove(p);
2427                 return true;
2428         }
2429         return false;
2430 }
2431
2432 /**
2433  * tb_register_property_dir() - Register property directory to the host
2434  * @key: Key (name) of the directory to add
2435  * @dir: Directory to add
2436  *
2437  * Service drivers can use this function to add new property directory
2438  * to the host available properties. The other connected hosts are
2439  * notified so they can re-read properties of this host if they are
2440  * interested.
2441  *
2442  * Return: %0 on success and negative errno on failure
2443  */
2444 int tb_register_property_dir(const char *key, struct tb_property_dir *dir)
2445 {
2446         int ret;
2447
2448         if (WARN_ON(!xdomain_property_dir))
2449                 return -EAGAIN;
2450
2451         if (!key || strlen(key) > 8)
2452                 return -EINVAL;
2453
2454         mutex_lock(&xdomain_lock);
2455         if (tb_property_find(xdomain_property_dir, key,
2456                              TB_PROPERTY_TYPE_DIRECTORY)) {
2457                 ret = -EEXIST;
2458                 goto err_unlock;
2459         }
2460
2461         ret = tb_property_add_dir(xdomain_property_dir, key, dir);
2462         if (ret)
2463                 goto err_unlock;
2464
2465         xdomain_property_block_gen++;
2466
2467         mutex_unlock(&xdomain_lock);
2468         update_all_xdomains();
2469         return 0;
2470
2471 err_unlock:
2472         mutex_unlock(&xdomain_lock);
2473         return ret;
2474 }
2475 EXPORT_SYMBOL_GPL(tb_register_property_dir);
2476
2477 /**
2478  * tb_unregister_property_dir() - Removes property directory from host
2479  * @key: Key (name) of the directory
2480  * @dir: Directory to remove
2481  *
2482  * This will remove the existing directory from this host and notify the
2483  * connected hosts about the change.
2484  */
2485 void tb_unregister_property_dir(const char *key, struct tb_property_dir *dir)
2486 {
2487         int ret = 0;
2488
2489         mutex_lock(&xdomain_lock);
2490         if (remove_directory(key, dir))
2491                 xdomain_property_block_gen++;
2492         mutex_unlock(&xdomain_lock);
2493
2494         if (!ret)
2495                 update_all_xdomains();
2496 }
2497 EXPORT_SYMBOL_GPL(tb_unregister_property_dir);
2498
2499 int tb_xdomain_init(void)
2500 {
2501         xdomain_property_dir = tb_property_create_dir(NULL);
2502         if (!xdomain_property_dir)
2503                 return -ENOMEM;
2504
2505         /*
2506          * Initialize standard set of properties without any service
2507          * directories. Those will be added by service drivers
2508          * themselves when they are loaded.
2509          *
2510          * Rest of the properties are filled dynamically based on these
2511          * when the P2P connection is made.
2512          */
2513         tb_property_add_immediate(xdomain_property_dir, "vendorid",
2514                                   PCI_VENDOR_ID_INTEL);
2515         tb_property_add_text(xdomain_property_dir, "vendorid", "Intel Corp.");
2516         tb_property_add_immediate(xdomain_property_dir, "deviceid", 0x1);
2517         tb_property_add_immediate(xdomain_property_dir, "devicerv", 0x80000100);
2518
2519         xdomain_property_block_gen = get_random_u32();
2520         return 0;
2521 }
2522
2523 void tb_xdomain_exit(void)
2524 {
2525         tb_property_free_dir(xdomain_property_dir);
2526 }