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_switch *sw = tb_to_switch(xd->dev.parent);
 541         struct tb_xdp_link_state_status_response res;
 542         struct tb_port *port = tb_port_at(xd->route, sw);
 543         u32 val[2];
 544         int ret;
 545
 546         memset(&res, 0, sizeof(res));
 547         tb_xdp_fill_header(&res.hdr, xd->route, sequence,
 548                            LINK_STATE_STATUS_RESPONSE, sizeof(res));
 549
 550         ret = tb_port_read(port, val, TB_CFG_PORT,
 551                            port->cap_phy + LANE_ADP_CS_0, ARRAY_SIZE(val));
 552         if (ret)
 553                 return ret;
 554
 555         res.slw = (val[0] & LANE_ADP_CS_0_SUPPORTED_WIDTH_MASK) >>
 556                         LANE_ADP_CS_0_SUPPORTED_WIDTH_SHIFT;
 557         res.sls = (val[0] & LANE_ADP_CS_0_SUPPORTED_SPEED_MASK) >>
 558                         LANE_ADP_CS_0_SUPPORTED_SPEED_SHIFT;
 559         res.tls = val[1] & LANE_ADP_CS_1_TARGET_SPEED_MASK;
 560         res.tlw = (val[1] & LANE_ADP_CS_1_TARGET_WIDTH_MASK) >>
 561                         LANE_ADP_CS_1_TARGET_WIDTH_SHIFT;
 562
 563         return __tb_xdomain_response(ctl, &res, sizeof(res),
 564                                      TB_CFG_PKG_XDOMAIN_RESP);
 565 }
 566
 567 static int tb_xdp_link_state_change_request(struct tb_ctl *ctl, u64 route,
 568                                             u8 sequence, u8 tlw, u8 tls)
 569 {
 570         struct tb_xdp_link_state_change_response res;
 571         struct tb_xdp_link_state_change req;
 572         int ret;
 573
 574         memset(&req, 0, sizeof(req));
 575         tb_xdp_fill_header(&req.hdr, route, sequence, LINK_STATE_CHANGE_REQUEST,
 576                            sizeof(req));
 577         req.tlw = tlw;
 578         req.tls = tls;
 579
 580         memset(&res, 0, sizeof(res));
 581         ret = __tb_xdomain_request(ctl, &req, sizeof(req), TB_CFG_PKG_XDOMAIN_REQ,
 582                                    &res, sizeof(res), TB_CFG_PKG_XDOMAIN_RESP,
 583                                    XDOMAIN_DEFAULT_TIMEOUT);
 584         if (ret)
 585                 return ret;
 586
 587         ret = tb_xdp_handle_error(&res.err);
 588         if (ret)
 589                 return ret;
 590
 591         return res.status != 0 ? -EREMOTEIO : 0;
 592 }
 593
 594 static int tb_xdp_link_state_change_response(struct tb_ctl *ctl, u64 route,
 595                                              u8 sequence, u32 status)
 596 {
 597         struct tb_xdp_link_state_change_response res;
 598
 599         memset(&res, 0, sizeof(res));
 600         tb_xdp_fill_header(&res.hdr, route, sequence, LINK_STATE_CHANGE_RESPONSE,
 601                            sizeof(res));
 602
 603         res.status = status;
 604
 605         return __tb_xdomain_response(ctl, &res, sizeof(res),
 606                                      TB_CFG_PKG_XDOMAIN_RESP);
 607 }
 608
 609 /**
 610  * tb_register_protocol_handler() - Register protocol handler
 611  * @handler: Handler to register
 612  *
 613  * This allows XDomain service drivers to hook into incoming XDomain
 614  * messages. After this function is called the service driver needs to
 615  * be able to handle calls to callback whenever a package with the
 616  * registered protocol is received.
 617  */
 618 int tb_register_protocol_handler(struct tb_protocol_handler *handler)
 619 {
 620         if (!handler->uuid || !handler->callback)
 621                 return -EINVAL;
 622         if (uuid_equal(handler->uuid, &tb_xdp_uuid))
 623                 return -EINVAL;
 624
 625         mutex_lock(&xdomain_lock);
 626         list_add_tail(&handler->list, &protocol_handlers);
 627         mutex_unlock(&xdomain_lock);
 628
 629         return 0;
 630 }
 631 EXPORT_SYMBOL_GPL(tb_register_protocol_handler);
 632
 633 /**
 634  * tb_unregister_protocol_handler() - Unregister protocol handler
 635  * @handler: Handler to unregister
 636  *
 637  * Removes the previously registered protocol handler.
 638  */
 639 void tb_unregister_protocol_handler(struct tb_protocol_handler *handler)
 640 {
 641         mutex_lock(&xdomain_lock);
 642         list_del_init(&handler->list);
 643         mutex_unlock(&xdomain_lock);
 644 }
 645 EXPORT_SYMBOL_GPL(tb_unregister_protocol_handler);
 646
 647 static void update_property_block(struct tb_xdomain *xd)
 648 {
 649         mutex_lock(&xdomain_lock);
 650         mutex_lock(&xd->lock);
 651         /*
 652          * If the local property block is not up-to-date, rebuild it now
 653          * based on the global property template.
 654          */
 655         if (!xd->local_property_block ||
 656             xd->local_property_block_gen < xdomain_property_block_gen) {
 657                 struct tb_property_dir *dir;
 658                 int ret, block_len;
 659                 u32 *block;
 660
 661                 dir = tb_property_copy_dir(xdomain_property_dir);
 662                 if (!dir) {
 663                         dev_warn(&xd->dev, "failed to copy properties\n");
 664                         goto out_unlock;
 665                 }
 666
 667                 /* Fill in non-static properties now */
 668                 tb_property_add_text(dir, "deviceid", utsname()->nodename);
 669                 tb_property_add_immediate(dir, "maxhopid", xd->local_max_hopid);
 670
 671                 ret = tb_property_format_dir(dir, NULL, 0);
 672                 if (ret < 0) {
 673                         dev_warn(&xd->dev, "local property block creation failed\n");
 674                         tb_property_free_dir(dir);
 675                         goto out_unlock;
 676                 }
 677
 678                 block_len = ret;
 679                 block = kcalloc(block_len, sizeof(*block), GFP_KERNEL);
 680                 if (!block) {
 681                         tb_property_free_dir(dir);
 682                         goto out_unlock;
 683                 }
 684
 685                 ret = tb_property_format_dir(dir, block, block_len);
 686                 if (ret) {
 687                         dev_warn(&xd->dev, "property block generation failed\n");
 688                         tb_property_free_dir(dir);
 689                         kfree(block);
 690                         goto out_unlock;
 691                 }
 692
 693                 tb_property_free_dir(dir);
 694                 /* Release the previous block */
 695                 kfree(xd->local_property_block);
 696                 /* Assign new one */
 697                 xd->local_property_block = block;
 698                 xd->local_property_block_len = block_len;
 699                 xd->local_property_block_gen = xdomain_property_block_gen;
 700         }
 701
 702 out_unlock:
 703         mutex_unlock(&xd->lock);
 704         mutex_unlock(&xdomain_lock);
 705 }
 706
 707 static void tb_xdp_handle_request(struct work_struct *work)
 708 {
 709         struct xdomain_request_work *xw = container_of(work, typeof(*xw), work);
 710         const struct tb_xdp_header *pkg = xw->pkg;
 711         const struct tb_xdomain_header *xhdr = &pkg->xd_hdr;
 712         struct tb *tb = xw->tb;
 713         struct tb_ctl *ctl = tb->ctl;
 714         struct tb_xdomain *xd;
 715         const uuid_t *uuid;
 716         int ret = 0;
 717         u32 sequence;
 718         u64 route;
 719
 720         route = ((u64)xhdr->route_hi << 32 | xhdr->route_lo) & ~BIT_ULL(63);
 721         sequence = xhdr->length_sn & TB_XDOMAIN_SN_MASK;
 722         sequence >>= TB_XDOMAIN_SN_SHIFT;
 723
 724         mutex_lock(&tb->lock);
 725         if (tb->root_switch)
 726                 uuid = tb->root_switch->uuid;
 727         else
 728                 uuid = NULL;
 729         mutex_unlock(&tb->lock);
 730
 731         if (!uuid) {
 732                 tb_xdp_error_response(ctl, route, sequence, ERROR_NOT_READY);
 733                 goto out;
 734         }
 735
 736         xd = tb_xdomain_find_by_route_locked(tb, route);
 737         if (xd)
 738                 update_property_block(xd);
 739
 740         switch (pkg->type) {
 741         case PROPERTIES_REQUEST:
 742                 tb_dbg(tb, "%llx: received XDomain properties request\n", route);
 743                 if (xd) {
 744                         ret = tb_xdp_properties_response(tb, ctl, xd, sequence,
 745                                 (const struct tb_xdp_properties *)pkg);
 746                 }
 747                 break;
 748
 749         case PROPERTIES_CHANGED_REQUEST:
 750                 tb_dbg(tb, "%llx: received XDomain properties changed request\n",
 751                        route);
 752
 753                 ret = tb_xdp_properties_changed_response(ctl, route, sequence);
 754
 755                 /*
 756                  * Since the properties have been changed, let's update
 757                  * the xdomain related to this connection as well in
 758                  * case there is a change in services it offers.
 759                  */
 760                 if (xd && device_is_registered(&xd->dev))
 761                         queue_delayed_work(tb->wq, &xd->state_work,
 762                                            msecs_to_jiffies(XDOMAIN_SHORT_TIMEOUT));
 763                 break;
 764
 765         case UUID_REQUEST_OLD:
 766         case UUID_REQUEST:
 767                 tb_dbg(tb, "%llx: received XDomain UUID request\n", route);
 768                 ret = tb_xdp_uuid_response(ctl, route, sequence, uuid);
 769                 break;
 770
 771         case LINK_STATE_STATUS_REQUEST:
 772                 tb_dbg(tb, "%llx: received XDomain link state status request\n",
 773                        route);
 774
 775                 if (xd) {
 776                         ret = tb_xdp_link_state_status_response(tb, ctl, xd,
 777                                                                 sequence);
 778                 } else {
 779                         tb_xdp_error_response(ctl, route, sequence,
 780                                               ERROR_NOT_READY);
 781                 }
 782                 break;
 783
 784         case LINK_STATE_CHANGE_REQUEST:
 785                 tb_dbg(tb, "%llx: received XDomain link state change request\n",
 786                        route);
 787
 788                 if (xd && xd->state == XDOMAIN_STATE_BONDING_UUID_HIGH) {
 789                         const struct tb_xdp_link_state_change *lsc =
 790                                 (const struct tb_xdp_link_state_change *)pkg;
 791
 792                         ret = tb_xdp_link_state_change_response(ctl, route,
 793                                                                 sequence, 0);
 794                         xd->target_link_width = lsc->tlw;
 795                         queue_delayed_work(tb->wq, &xd->state_work,
 796                                            msecs_to_jiffies(XDOMAIN_SHORT_TIMEOUT));
 797                 } else {
 798                         tb_xdp_error_response(ctl, route, sequence,
 799                                               ERROR_NOT_READY);
 800                 }
 801                 break;
 802
 803         default:
 804                 tb_dbg(tb, "%llx: unknown XDomain request %#x\n", route, pkg->type);
 805                 tb_xdp_error_response(ctl, route, sequence,
 806                                       ERROR_NOT_SUPPORTED);
 807                 break;
 808         }
 809
 810         tb_xdomain_put(xd);
 811
 812         if (ret) {
 813                 tb_warn(tb, "failed to send XDomain response for %#x\n",
 814                         pkg->type);
 815         }
 816
 817 out:
 818         kfree(xw->pkg);
 819         kfree(xw);
 820
 821         tb_domain_put(tb);
 822 }
 823
 824 static bool
 825 tb_xdp_schedule_request(struct tb *tb, const struct tb_xdp_header *hdr,
 826                         size_t size)
 827 {
 828         struct xdomain_request_work *xw;
 829
 830         xw = kmalloc(sizeof(*xw), GFP_KERNEL);
 831         if (!xw)
 832                 return false;
 833
 834         INIT_WORK(&xw->work, tb_xdp_handle_request);
 835         xw->pkg = kmemdup(hdr, size, GFP_KERNEL);
 836         if (!xw->pkg) {
 837                 kfree(xw);
 838                 return false;
 839         }
 840         xw->tb = tb_domain_get(tb);
 841
 842         schedule_work(&xw->work);
 843         return true;
 844 }
 845
 846 /**
 847  * tb_register_service_driver() - Register XDomain service driver
 848  * @drv: Driver to register
 849  *
 850  * Registers new service driver from @drv to the bus.
 851  */
 852 int tb_register_service_driver(struct tb_service_driver *drv)
 853 {
 854         drv->driver.bus = &tb_bus_type;
 855         return driver_register(&drv->driver);
 856 }
 857 EXPORT_SYMBOL_GPL(tb_register_service_driver);
 858
 859 /**
 860  * tb_unregister_service_driver() - Unregister XDomain service driver
 861  * @drv: Driver to unregister
 862  *
 863  * Unregisters XDomain service driver from the bus.
 864  */
 865 void tb_unregister_service_driver(struct tb_service_driver *drv)
 866 {
 867         driver_unregister(&drv->driver);
 868 }
 869 EXPORT_SYMBOL_GPL(tb_unregister_service_driver);
 870
 871 static ssize_t key_show(struct device *dev, struct device_attribute *attr,
 872                         char *buf)
 873 {
 874         struct tb_service *svc = container_of(dev, struct tb_service, dev);
 875
 876         /*
 877          * It should be null terminated but anything else is pretty much
 878          * allowed.
 879          */
 880         return sysfs_emit(buf, "%*pE\n", (int)strlen(svc->key), svc->key);
 881 }
 882 static DEVICE_ATTR_RO(key);
 883
 884 static int get_modalias(const struct tb_service *svc, char *buf, size_t size)
 885 {
 886         return snprintf(buf, size, "tbsvc:k%sp%08Xv%08Xr%08X", svc->key,
 887                         svc->prtcid, svc->prtcvers, svc->prtcrevs);
 888 }
 889
 890 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
 891                              char *buf)
 892 {
 893         struct tb_service *svc = container_of(dev, struct tb_service, dev);
 894
 895         /* Full buffer size except new line and null termination */
 896         get_modalias(svc, buf, PAGE_SIZE - 2);
 897         return strlen(strcat(buf, "\n"));
 898 }
 899 static DEVICE_ATTR_RO(modalias);
 900
 901 static ssize_t prtcid_show(struct device *dev, struct device_attribute *attr,
 902                            char *buf)
 903 {
 904         struct tb_service *svc = container_of(dev, struct tb_service, dev);
 905
 906         return sysfs_emit(buf, "%u\n", svc->prtcid);
 907 }
 908 static DEVICE_ATTR_RO(prtcid);
 909
 910 static ssize_t prtcvers_show(struct device *dev, struct device_attribute *attr,
 911                              char *buf)
 912 {
 913         struct tb_service *svc = container_of(dev, struct tb_service, dev);
 914
 915         return sysfs_emit(buf, "%u\n", svc->prtcvers);
 916 }
 917 static DEVICE_ATTR_RO(prtcvers);
 918
 919 static ssize_t prtcrevs_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         return sysfs_emit(buf, "%u\n", svc->prtcrevs);
 925 }
 926 static DEVICE_ATTR_RO(prtcrevs);
 927
 928 static ssize_t prtcstns_show(struct device *dev, struct device_attribute *attr,
 929                              char *buf)
 930 {
 931         struct tb_service *svc = container_of(dev, struct tb_service, dev);
 932
 933         return sysfs_emit(buf, "0x%08x\n", svc->prtcstns);
 934 }
 935 static DEVICE_ATTR_RO(prtcstns);
 936
 937 static struct attribute *tb_service_attrs[] = {
 938         &dev_attr_key.attr,
 939         &dev_attr_modalias.attr,
 940         &dev_attr_prtcid.attr,
 941         &dev_attr_prtcvers.attr,
 942         &dev_attr_prtcrevs.attr,
 943         &dev_attr_prtcstns.attr,
 944         NULL,
 945 };
 946
 947 static const struct attribute_group tb_service_attr_group = {
 948         .attrs = tb_service_attrs,
 949 };
 950
 951 static const struct attribute_group *tb_service_attr_groups[] = {
 952         &tb_service_attr_group,
 953         NULL,
 954 };
 955
 956 static int tb_service_uevent(const struct device *dev, struct kobj_uevent_env *env)
 957 {
 958         const struct tb_service *svc = container_of_const(dev, struct tb_service, dev);
 959         char modalias[64];
 960
 961         get_modalias(svc, modalias, sizeof(modalias));
 962         return add_uevent_var(env, "MODALIAS=%s", modalias);
 963 }
 964
 965 static void tb_service_release(struct device *dev)
 966 {
 967         struct tb_service *svc = container_of(dev, struct tb_service, dev);
 968         struct tb_xdomain *xd = tb_service_parent(svc);
 969
 970         tb_service_debugfs_remove(svc);
 971         ida_simple_remove(&xd->service_ids, svc->id);
 972         kfree(svc->key);
 973         kfree(svc);
 974 }
 975
 976 struct device_type tb_service_type = {
 977         .name = "thunderbolt_service",
 978         .groups = tb_service_attr_groups,
 979         .uevent = tb_service_uevent,
 980         .release = tb_service_release,
 981 };
 982 EXPORT_SYMBOL_GPL(tb_service_type);
 983
 984 static int remove_missing_service(struct device *dev, void *data)
 985 {
 986         struct tb_xdomain *xd = data;
 987         struct tb_service *svc;
 988
 989         svc = tb_to_service(dev);
 990         if (!svc)
 991                 return 0;
 992
 993         if (!tb_property_find(xd->remote_properties, svc->key,
 994                               TB_PROPERTY_TYPE_DIRECTORY))
 995                 device_unregister(dev);
 996
 997         return 0;
 998 }
 999
1000 static int find_service(struct device *dev, void *data)
1001 {
1002         const struct tb_property *p = data;
1003         struct tb_service *svc;
1004
1005         svc = tb_to_service(dev);
1006         if (!svc)
1007                 return 0;
1008
1009         return !strcmp(svc->key, p->key);
1010 }
1011
1012 static int populate_service(struct tb_service *svc,
1013                             struct tb_property *property)
1014 {
1015         struct tb_property_dir *dir = property->value.dir;
1016         struct tb_property *p;
1017
1018         /* Fill in standard properties */
1019         p = tb_property_find(dir, "prtcid", TB_PROPERTY_TYPE_VALUE);
1020         if (p)
1021                 svc->prtcid = p->value.immediate;
1022         p = tb_property_find(dir, "prtcvers", TB_PROPERTY_TYPE_VALUE);
1023         if (p)
1024                 svc->prtcvers = p->value.immediate;
1025         p = tb_property_find(dir, "prtcrevs", TB_PROPERTY_TYPE_VALUE);
1026         if (p)
1027                 svc->prtcrevs = p->value.immediate;
1028         p = tb_property_find(dir, "prtcstns", TB_PROPERTY_TYPE_VALUE);
1029         if (p)
1030                 svc->prtcstns = p->value.immediate;
1031
1032         svc->key = kstrdup(property->key, GFP_KERNEL);
1033         if (!svc->key)
1034                 return -ENOMEM;
1035
1036         return 0;
1037 }
1038
1039 static void enumerate_services(struct tb_xdomain *xd)
1040 {
1041         struct tb_service *svc;
1042         struct tb_property *p;
1043         struct device *dev;
1044         int id;
1045
1046         /*
1047          * First remove all services that are not available anymore in
1048          * the updated property block.
1049          */
1050         device_for_each_child_reverse(&xd->dev, xd, remove_missing_service);
1051
1052         /* Then re-enumerate properties creating new services as we go */
1053         tb_property_for_each(xd->remote_properties, p) {
1054                 if (p->type != TB_PROPERTY_TYPE_DIRECTORY)
1055                         continue;
1056
1057                 /* If the service exists already we are fine */
1058                 dev = device_find_child(&xd->dev, p, find_service);
1059                 if (dev) {
1060                         put_device(dev);
1061                         continue;
1062                 }
1063
1064                 svc = kzalloc(sizeof(*svc), GFP_KERNEL);
1065                 if (!svc)
1066                         break;
1067
1068                 if (populate_service(svc, p)) {
1069                         kfree(svc);
1070                         break;
1071                 }
1072
1073                 id = ida_simple_get(&xd->service_ids, 0, 0, GFP_KERNEL);
1074                 if (id < 0) {
1075                         kfree(svc->key);
1076                         kfree(svc);
1077                         break;
1078                 }
1079                 svc->id = id;
1080                 svc->dev.bus = &tb_bus_type;
1081                 svc->dev.type = &tb_service_type;
1082                 svc->dev.parent = &xd->dev;
1083                 dev_set_name(&svc->dev, "%s.%d", dev_name(&xd->dev), svc->id);
1084
1085                 tb_service_debugfs_init(svc);
1086
1087                 if (device_register(&svc->dev)) {
1088                         put_device(&svc->dev);
1089                         break;
1090                 }
1091         }
1092 }
1093
1094 static int populate_properties(struct tb_xdomain *xd,
1095                                struct tb_property_dir *dir)
1096 {
1097         const struct tb_property *p;
1098
1099         /* Required properties */
1100         p = tb_property_find(dir, "deviceid", TB_PROPERTY_TYPE_VALUE);
1101         if (!p)
1102                 return -EINVAL;
1103         xd->device = p->value.immediate;
1104
1105         p = tb_property_find(dir, "vendorid", TB_PROPERTY_TYPE_VALUE);
1106         if (!p)
1107                 return -EINVAL;
1108         xd->vendor = p->value.immediate;
1109
1110         p = tb_property_find(dir, "maxhopid", TB_PROPERTY_TYPE_VALUE);
1111         /*
1112          * USB4 inter-domain spec suggests using 15 as HopID if the
1113          * other end does not announce it in a property. This is for
1114          * TBT3 compatibility.
1115          */
1116         xd->remote_max_hopid = p ? p->value.immediate : XDOMAIN_DEFAULT_MAX_HOPID;
1117
1118         kfree(xd->device_name);
1119         xd->device_name = NULL;
1120         kfree(xd->vendor_name);
1121         xd->vendor_name = NULL;
1122
1123         /* Optional properties */
1124         p = tb_property_find(dir, "deviceid", TB_PROPERTY_TYPE_TEXT);
1125         if (p)
1126                 xd->device_name = kstrdup(p->value.text, GFP_KERNEL);
1127         p = tb_property_find(dir, "vendorid", TB_PROPERTY_TYPE_TEXT);
1128         if (p)
1129                 xd->vendor_name = kstrdup(p->value.text, GFP_KERNEL);
1130
1131         return 0;
1132 }
1133
1134 static int tb_xdomain_update_link_attributes(struct tb_xdomain *xd)
1135 {
1136         bool change = false;
1137         struct tb_port *port;
1138         int ret;
1139
1140         port = tb_port_at(xd->route, tb_xdomain_parent(xd));
1141
1142         ret = tb_port_get_link_speed(port);
1143         if (ret < 0)
1144                 return ret;
1145
1146         if (xd->link_speed != ret)
1147                 change = true;
1148
1149         xd->link_speed = ret;
1150
1151         ret = tb_port_get_link_width(port);
1152         if (ret < 0)
1153                 return ret;
1154
1155         if (xd->link_width != ret)
1156                 change = true;
1157
1158         xd->link_width = ret;
1159
1160         if (change)
1161                 kobject_uevent(&xd->dev.kobj, KOBJ_CHANGE);
1162
1163         return 0;
1164 }
1165
1166 static int tb_xdomain_get_uuid(struct tb_xdomain *xd)
1167 {
1168         struct tb *tb = xd->tb;
1169         uuid_t uuid;
1170         u64 route;
1171         int ret;
1172
1173         dev_dbg(&xd->dev, "requesting remote UUID\n");
1174
1175         ret = tb_xdp_uuid_request(tb->ctl, xd->route, xd->state_retries, &uuid,
1176                                   &route);
1177         if (ret < 0) {
1178                 if (xd->state_retries-- > 0) {
1179                         dev_dbg(&xd->dev, "failed to request UUID, retrying\n");
1180                         return -EAGAIN;
1181                 }
1182                 dev_dbg(&xd->dev, "failed to read remote UUID\n");
1183                 return ret;
1184         }
1185
1186         dev_dbg(&xd->dev, "got remote UUID %pUb\n", &uuid);
1187
1188         if (uuid_equal(&uuid, xd->local_uuid)) {
1189                 if (route == xd->route)
1190                         dev_dbg(&xd->dev, "loop back detected\n");
1191                 else
1192                         dev_dbg(&xd->dev, "intra-domain loop detected\n");
1193
1194                 /* Don't bond lanes automatically for loops */
1195                 xd->bonding_possible = false;
1196         }
1197
1198         /*
1199          * If the UUID is different, there is another domain connected
1200          * so mark this one unplugged and wait for the connection
1201          * manager to replace it.
1202          */
1203         if (xd->remote_uuid && !uuid_equal(&uuid, xd->remote_uuid)) {
1204                 dev_dbg(&xd->dev, "remote UUID is different, unplugging\n");
1205                 xd->is_unplugged = true;
1206                 return -ENODEV;
1207         }
1208
1209         /* First time fill in the missing UUID */
1210         if (!xd->remote_uuid) {
1211                 xd->remote_uuid = kmemdup(&uuid, sizeof(uuid_t), GFP_KERNEL);
1212                 if (!xd->remote_uuid)
1213                         return -ENOMEM;
1214         }
1215
1216         return 0;
1217 }
1218
1219 static int tb_xdomain_get_link_status(struct tb_xdomain *xd)
1220 {
1221         struct tb *tb = xd->tb;
1222         u8 slw, tlw, sls, tls;
1223         int ret;
1224
1225         dev_dbg(&xd->dev, "sending link state status request to %pUb\n",
1226                 xd->remote_uuid);
1227
1228         ret = tb_xdp_link_state_status_request(tb->ctl, xd->route,
1229                                                xd->state_retries, &slw, &tlw, &sls,
1230                                                &tls);
1231         if (ret) {
1232                 if (ret != -EOPNOTSUPP && xd->state_retries-- > 0) {
1233                         dev_dbg(&xd->dev,
1234                                 "failed to request remote link status, retrying\n");
1235                         return -EAGAIN;
1236                 }
1237                 dev_dbg(&xd->dev, "failed to receive remote link status\n");
1238                 return ret;
1239         }
1240
1241         dev_dbg(&xd->dev, "remote link supports width %#x speed %#x\n", slw, sls);
1242
1243         if (slw < LANE_ADP_CS_0_SUPPORTED_WIDTH_DUAL) {
1244                 dev_dbg(&xd->dev, "remote adapter is single lane only\n");
1245                 return -EOPNOTSUPP;
1246         }
1247
1248         return 0;
1249 }
1250
1251 static int tb_xdomain_link_state_change(struct tb_xdomain *xd,
1252                                         unsigned int width)
1253 {
1254         struct tb_switch *sw = tb_to_switch(xd->dev.parent);
1255         struct tb_port *port = tb_port_at(xd->route, sw);
1256         struct tb *tb = xd->tb;
1257         u8 tlw, tls;
1258         u32 val;
1259         int ret;
1260
1261         if (width == 2)
1262                 tlw = LANE_ADP_CS_1_TARGET_WIDTH_DUAL;
1263         else if (width == 1)
1264                 tlw = LANE_ADP_CS_1_TARGET_WIDTH_SINGLE;
1265         else
1266                 return -EINVAL;
1267
1268         /* Use the current target speed */
1269         ret = tb_port_read(port, &val, TB_CFG_PORT, port->cap_phy + LANE_ADP_CS_1, 1);
1270         if (ret)
1271                 return ret;
1272         tls = val & LANE_ADP_CS_1_TARGET_SPEED_MASK;
1273
1274         dev_dbg(&xd->dev, "sending link state change request with width %#x speed %#x\n",
1275                 tlw, tls);
1276
1277         ret = tb_xdp_link_state_change_request(tb->ctl, xd->route,
1278                                                xd->state_retries, tlw, tls);
1279         if (ret) {
1280                 if (ret != -EOPNOTSUPP && xd->state_retries-- > 0) {
1281                         dev_dbg(&xd->dev,
1282                                 "failed to change remote link state, retrying\n");
1283                         return -EAGAIN;
1284                 }
1285                 dev_err(&xd->dev, "failed request link state change, aborting\n");
1286                 return ret;
1287         }
1288
1289         dev_dbg(&xd->dev, "received link state change response\n");
1290         return 0;
1291 }
1292
1293 static int tb_xdomain_bond_lanes_uuid_high(struct tb_xdomain *xd)
1294 {
1295         struct tb_port *port;
1296         int ret, width;
1297
1298         if (xd->target_link_width == LANE_ADP_CS_1_TARGET_WIDTH_SINGLE) {
1299                 width = 1;
1300         } else if (xd->target_link_width == LANE_ADP_CS_1_TARGET_WIDTH_DUAL) {
1301                 width = 2;
1302         } else {
1303                 if (xd->state_retries-- > 0) {
1304                         dev_dbg(&xd->dev,
1305                                 "link state change request not received yet, retrying\n");
1306                         return -EAGAIN;
1307                 }
1308                 dev_dbg(&xd->dev, "timeout waiting for link change request\n");
1309                 return -ETIMEDOUT;
1310         }
1311
1312         port = tb_port_at(xd->route, tb_xdomain_parent(xd));
1313
1314         /*
1315          * We can't use tb_xdomain_lane_bonding_enable() here because it
1316          * is the other side that initiates lane bonding. So here we
1317          * just set the width to both lane adapters and wait for the
1318          * link to transition bonded.
1319          */
1320         ret = tb_port_set_link_width(port->dual_link_port, width);
1321         if (ret) {
1322                 tb_port_warn(port->dual_link_port,
1323                              "failed to set link width to %d\n", width);
1324                 return ret;
1325         }
1326
1327         ret = tb_port_set_link_width(port, width);
1328         if (ret) {
1329                 tb_port_warn(port, "failed to set link width to %d\n", width);
1330                 return ret;
1331         }
1332
1333         ret = tb_port_wait_for_link_width(port, width, XDOMAIN_BONDING_TIMEOUT);
1334         if (ret) {
1335                 dev_warn(&xd->dev, "error waiting for link width to become %d\n",
1336                          width);
1337                 return ret;
1338         }
1339
1340         port->bonded = width == 2;
1341         port->dual_link_port->bonded = width == 2;
1342
1343         tb_port_update_credits(port);
1344         tb_xdomain_update_link_attributes(xd);
1345
1346         dev_dbg(&xd->dev, "lane bonding %s\n", str_enabled_disabled(width == 2));
1347         return 0;
1348 }
1349
1350 static int tb_xdomain_get_properties(struct tb_xdomain *xd)
1351 {
1352         struct tb_property_dir *dir;
1353         struct tb *tb = xd->tb;
1354         bool update = false;
1355         u32 *block = NULL;
1356         u32 gen = 0;
1357         int ret;
1358
1359         dev_dbg(&xd->dev, "requesting remote properties\n");
1360
1361         ret = tb_xdp_properties_request(tb->ctl, xd->route, xd->local_uuid,
1362                                         xd->remote_uuid, xd->state_retries,
1363                                         &block, &gen);
1364         if (ret < 0) {
1365                 if (xd->state_retries-- > 0) {
1366                         dev_dbg(&xd->dev,
1367                                 "failed to request remote properties, retrying\n");
1368                         return -EAGAIN;
1369                 }
1370                 /* Give up now */
1371                 dev_err(&xd->dev, "failed read XDomain properties from %pUb\n",
1372                         xd->remote_uuid);
1373
1374                 return ret;
1375         }
1376
1377         mutex_lock(&xd->lock);
1378
1379         /* Only accept newer generation properties */
1380         if (xd->remote_properties && gen <= xd->remote_property_block_gen) {
1381                 ret = 0;
1382                 goto err_free_block;
1383         }
1384
1385         dir = tb_property_parse_dir(block, ret);
1386         if (!dir) {
1387                 dev_err(&xd->dev, "failed to parse XDomain properties\n");
1388                 ret = -ENOMEM;
1389                 goto err_free_block;
1390         }
1391
1392         ret = populate_properties(xd, dir);
1393         if (ret) {
1394                 dev_err(&xd->dev, "missing XDomain properties in response\n");
1395                 goto err_free_dir;
1396         }
1397
1398         /* Release the existing one */
1399         if (xd->remote_properties) {
1400                 tb_property_free_dir(xd->remote_properties);
1401                 update = true;
1402         }
1403
1404         xd->remote_properties = dir;
1405         xd->remote_property_block_gen = gen;
1406
1407         tb_xdomain_update_link_attributes(xd);
1408
1409         mutex_unlock(&xd->lock);
1410
1411         kfree(block);
1412
1413         /*
1414          * Now the device should be ready enough so we can add it to the
1415          * bus and let userspace know about it. If the device is already
1416          * registered, we notify the userspace that it has changed.
1417          */
1418         if (!update) {
1419                 /*
1420                  * Now disable lane 1 if bonding was not enabled. Do
1421                  * this only if bonding was possible at the beginning
1422                  * (that is we are the connection manager and there are
1423                  * two lanes).
1424                  */
1425                 if (xd->bonding_possible) {
1426                         struct tb_port *port;
1427
1428                         port = tb_port_at(xd->route, tb_xdomain_parent(xd));
1429                         if (!port->bonded)
1430                                 tb_port_disable(port->dual_link_port);
1431                 }
1432
1433                 if (device_add(&xd->dev)) {
1434                         dev_err(&xd->dev, "failed to add XDomain device\n");
1435                         return -ENODEV;
1436                 }
1437                 dev_info(&xd->dev, "new host found, vendor=%#x device=%#x\n",
1438                          xd->vendor, xd->device);
1439                 if (xd->vendor_name && xd->device_name)
1440                         dev_info(&xd->dev, "%s %s\n", xd->vendor_name,
1441                                  xd->device_name);
1442
1443                 tb_xdomain_debugfs_init(xd);
1444         } else {
1445                 kobject_uevent(&xd->dev.kobj, KOBJ_CHANGE);
1446         }
1447
1448         enumerate_services(xd);
1449         return 0;
1450
1451 err_free_dir:
1452         tb_property_free_dir(dir);
1453 err_free_block:
1454         kfree(block);
1455         mutex_unlock(&xd->lock);
1456
1457         return ret;
1458 }
1459
1460 static void tb_xdomain_queue_uuid(struct tb_xdomain *xd)
1461 {
1462         xd->state = XDOMAIN_STATE_UUID;
1463         xd->state_retries = XDOMAIN_RETRIES;
1464         queue_delayed_work(xd->tb->wq, &xd->state_work,
1465                            msecs_to_jiffies(XDOMAIN_SHORT_TIMEOUT));
1466 }
1467
1468 static void tb_xdomain_queue_link_status(struct tb_xdomain *xd)
1469 {
1470         xd->state = XDOMAIN_STATE_LINK_STATUS;
1471         xd->state_retries = XDOMAIN_RETRIES;
1472         queue_delayed_work(xd->tb->wq, &xd->state_work,
1473                            msecs_to_jiffies(XDOMAIN_DEFAULT_TIMEOUT));
1474 }
1475
1476 static void tb_xdomain_queue_link_status2(struct tb_xdomain *xd)
1477 {
1478         xd->state = XDOMAIN_STATE_LINK_STATUS2;
1479         xd->state_retries = XDOMAIN_RETRIES;
1480         queue_delayed_work(xd->tb->wq, &xd->state_work,
1481                            msecs_to_jiffies(XDOMAIN_DEFAULT_TIMEOUT));
1482 }
1483
1484 static void tb_xdomain_queue_bonding(struct tb_xdomain *xd)
1485 {
1486         if (memcmp(xd->local_uuid, xd->remote_uuid, UUID_SIZE) > 0) {
1487                 dev_dbg(&xd->dev, "we have higher UUID, other side bonds the lanes\n");
1488                 xd->state = XDOMAIN_STATE_BONDING_UUID_HIGH;
1489         } else {
1490                 dev_dbg(&xd->dev, "we have lower UUID, bonding lanes\n");
1491                 xd->state = XDOMAIN_STATE_LINK_STATE_CHANGE;
1492         }
1493
1494         xd->state_retries = XDOMAIN_RETRIES;
1495         queue_delayed_work(xd->tb->wq, &xd->state_work,
1496                            msecs_to_jiffies(XDOMAIN_DEFAULT_TIMEOUT));
1497 }
1498
1499 static void tb_xdomain_queue_bonding_uuid_low(struct tb_xdomain *xd)
1500 {
1501         xd->state = XDOMAIN_STATE_BONDING_UUID_LOW;
1502         xd->state_retries = XDOMAIN_RETRIES;
1503         queue_delayed_work(xd->tb->wq, &xd->state_work,
1504                            msecs_to_jiffies(XDOMAIN_DEFAULT_TIMEOUT));
1505 }
1506
1507 static void tb_xdomain_queue_properties(struct tb_xdomain *xd)
1508 {
1509         xd->state = XDOMAIN_STATE_PROPERTIES;
1510         xd->state_retries = XDOMAIN_RETRIES;
1511         queue_delayed_work(xd->tb->wq, &xd->state_work,
1512                            msecs_to_jiffies(XDOMAIN_DEFAULT_TIMEOUT));
1513 }
1514
1515 static void tb_xdomain_queue_properties_changed(struct tb_xdomain *xd)
1516 {
1517         xd->properties_changed_retries = XDOMAIN_RETRIES;
1518         queue_delayed_work(xd->tb->wq, &xd->properties_changed_work,
1519                            msecs_to_jiffies(XDOMAIN_SHORT_TIMEOUT));
1520 }
1521
1522 static void tb_xdomain_state_work(struct work_struct *work)
1523 {
1524         struct tb_xdomain *xd = container_of(work, typeof(*xd), state_work.work);
1525         int ret, state = xd->state;
1526
1527         if (WARN_ON_ONCE(state < XDOMAIN_STATE_INIT ||
1528                          state > XDOMAIN_STATE_ERROR))
1529                 return;
1530
1531         dev_dbg(&xd->dev, "running state %s\n", state_names[state]);
1532
1533         switch (state) {
1534         case XDOMAIN_STATE_INIT:
1535                 if (xd->needs_uuid) {
1536                         tb_xdomain_queue_uuid(xd);
1537                 } else {
1538                         tb_xdomain_queue_properties_changed(xd);
1539                         tb_xdomain_queue_properties(xd);
1540                 }
1541                 break;
1542
1543         case XDOMAIN_STATE_UUID:
1544                 ret = tb_xdomain_get_uuid(xd);
1545                 if (ret) {
1546                         if (ret == -EAGAIN)
1547                                 goto retry_state;
1548                         xd->state = XDOMAIN_STATE_ERROR;
1549                 } else {
1550                         tb_xdomain_queue_properties_changed(xd);
1551                         if (xd->bonding_possible)
1552                                 tb_xdomain_queue_link_status(xd);
1553                         else
1554                                 tb_xdomain_queue_properties(xd);
1555                 }
1556                 break;
1557
1558         case XDOMAIN_STATE_LINK_STATUS:
1559                 ret = tb_xdomain_get_link_status(xd);
1560                 if (ret) {
1561                         if (ret == -EAGAIN)
1562                                 goto retry_state;
1563
1564                         /*
1565                          * If any of the lane bonding states fail we skip
1566                          * bonding completely and try to continue from
1567                          * reading properties.
1568                          */
1569                         tb_xdomain_queue_properties(xd);
1570                 } else {
1571                         tb_xdomain_queue_bonding(xd);
1572                 }
1573                 break;
1574
1575         case XDOMAIN_STATE_LINK_STATE_CHANGE:
1576                 ret = tb_xdomain_link_state_change(xd, 2);
1577                 if (ret) {
1578                         if (ret == -EAGAIN)
1579                                 goto retry_state;
1580                         tb_xdomain_queue_properties(xd);
1581                 } else {
1582                         tb_xdomain_queue_link_status2(xd);
1583                 }
1584                 break;
1585
1586         case XDOMAIN_STATE_LINK_STATUS2:
1587                 ret = tb_xdomain_get_link_status(xd);
1588                 if (ret) {
1589                         if (ret == -EAGAIN)
1590                                 goto retry_state;
1591                         tb_xdomain_queue_properties(xd);
1592                 } else {
1593                         tb_xdomain_queue_bonding_uuid_low(xd);
1594                 }
1595                 break;
1596
1597         case XDOMAIN_STATE_BONDING_UUID_LOW:
1598                 tb_xdomain_lane_bonding_enable(xd);
1599                 tb_xdomain_queue_properties(xd);
1600                 break;
1601
1602         case XDOMAIN_STATE_BONDING_UUID_HIGH:
1603                 if (tb_xdomain_bond_lanes_uuid_high(xd) == -EAGAIN)
1604                         goto retry_state;
1605                 tb_xdomain_queue_properties(xd);
1606                 break;
1607
1608         case XDOMAIN_STATE_PROPERTIES:
1609                 ret = tb_xdomain_get_properties(xd);
1610                 if (ret) {
1611                         if (ret == -EAGAIN)
1612                                 goto retry_state;
1613                         xd->state = XDOMAIN_STATE_ERROR;
1614                 } else {
1615                         xd->state = XDOMAIN_STATE_ENUMERATED;
1616                 }
1617                 break;
1618
1619         case XDOMAIN_STATE_ENUMERATED:
1620                 tb_xdomain_queue_properties(xd);
1621                 break;
1622
1623         case XDOMAIN_STATE_ERROR:
1624                 break;
1625
1626         default:
1627                 dev_warn(&xd->dev, "unexpected state %d\n", state);
1628                 break;
1629         }
1630
1631         return;
1632
1633 retry_state:
1634         queue_delayed_work(xd->tb->wq, &xd->state_work,
1635                            msecs_to_jiffies(XDOMAIN_DEFAULT_TIMEOUT));
1636 }
1637
1638 static void tb_xdomain_properties_changed(struct work_struct *work)
1639 {
1640         struct tb_xdomain *xd = container_of(work, typeof(*xd),
1641                                              properties_changed_work.work);
1642         int ret;
1643
1644         dev_dbg(&xd->dev, "sending properties changed notification\n");
1645
1646         ret = tb_xdp_properties_changed_request(xd->tb->ctl, xd->route,
1647                                 xd->properties_changed_retries, xd->local_uuid);
1648         if (ret) {
1649                 if (xd->properties_changed_retries-- > 0) {
1650                         dev_dbg(&xd->dev,
1651                                 "failed to send properties changed notification, retrying\n");
1652                         queue_delayed_work(xd->tb->wq,
1653                                            &xd->properties_changed_work,
1654                                            msecs_to_jiffies(XDOMAIN_DEFAULT_TIMEOUT));
1655                 }
1656                 dev_err(&xd->dev, "failed to send properties changed notification\n");
1657                 return;
1658         }
1659
1660         xd->properties_changed_retries = XDOMAIN_RETRIES;
1661 }
1662
1663 static ssize_t device_show(struct device *dev, struct device_attribute *attr,
1664                            char *buf)
1665 {
1666         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1667
1668         return sysfs_emit(buf, "%#x\n", xd->device);
1669 }
1670 static DEVICE_ATTR_RO(device);
1671
1672 static ssize_t
1673 device_name_show(struct device *dev, struct device_attribute *attr, char *buf)
1674 {
1675         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1676         int ret;
1677
1678         if (mutex_lock_interruptible(&xd->lock))
1679                 return -ERESTARTSYS;
1680         ret = sysfs_emit(buf, "%s\n", xd->device_name ?: "");
1681         mutex_unlock(&xd->lock);
1682
1683         return ret;
1684 }
1685 static DEVICE_ATTR_RO(device_name);
1686
1687 static ssize_t maxhopid_show(struct device *dev, struct device_attribute *attr,
1688                              char *buf)
1689 {
1690         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1691
1692         return sysfs_emit(buf, "%d\n", xd->remote_max_hopid);
1693 }
1694 static DEVICE_ATTR_RO(maxhopid);
1695
1696 static ssize_t vendor_show(struct device *dev, struct device_attribute *attr,
1697                            char *buf)
1698 {
1699         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1700
1701         return sysfs_emit(buf, "%#x\n", xd->vendor);
1702 }
1703 static DEVICE_ATTR_RO(vendor);
1704
1705 static ssize_t
1706 vendor_name_show(struct device *dev, struct device_attribute *attr, char *buf)
1707 {
1708         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1709         int ret;
1710
1711         if (mutex_lock_interruptible(&xd->lock))
1712                 return -ERESTARTSYS;
1713         ret = sysfs_emit(buf, "%s\n", xd->vendor_name ?: "");
1714         mutex_unlock(&xd->lock);
1715
1716         return ret;
1717 }
1718 static DEVICE_ATTR_RO(vendor_name);
1719
1720 static ssize_t unique_id_show(struct device *dev, struct device_attribute *attr,
1721                               char *buf)
1722 {
1723         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1724
1725         return sysfs_emit(buf, "%pUb\n", xd->remote_uuid);
1726 }
1727 static DEVICE_ATTR_RO(unique_id);
1728
1729 static ssize_t speed_show(struct device *dev, struct device_attribute *attr,
1730                           char *buf)
1731 {
1732         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1733
1734         return sysfs_emit(buf, "%u.0 Gb/s\n", xd->link_speed);
1735 }
1736
1737 static DEVICE_ATTR(rx_speed, 0444, speed_show, NULL);
1738 static DEVICE_ATTR(tx_speed, 0444, speed_show, NULL);
1739
1740 static ssize_t lanes_show(struct device *dev, struct device_attribute *attr,
1741                           char *buf)
1742 {
1743         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1744
1745         return sysfs_emit(buf, "%u\n", xd->link_width);
1746 }
1747
1748 static DEVICE_ATTR(rx_lanes, 0444, lanes_show, NULL);
1749 static DEVICE_ATTR(tx_lanes, 0444, lanes_show, NULL);
1750
1751 static struct attribute *xdomain_attrs[] = {
1752         &dev_attr_device.attr,
1753         &dev_attr_device_name.attr,
1754         &dev_attr_maxhopid.attr,
1755         &dev_attr_rx_lanes.attr,
1756         &dev_attr_rx_speed.attr,
1757         &dev_attr_tx_lanes.attr,
1758         &dev_attr_tx_speed.attr,
1759         &dev_attr_unique_id.attr,
1760         &dev_attr_vendor.attr,
1761         &dev_attr_vendor_name.attr,
1762         NULL,
1763 };
1764
1765 static const struct attribute_group xdomain_attr_group = {
1766         .attrs = xdomain_attrs,
1767 };
1768
1769 static const struct attribute_group *xdomain_attr_groups[] = {
1770         &xdomain_attr_group,
1771         NULL,
1772 };
1773
1774 static void tb_xdomain_release(struct device *dev)
1775 {
1776         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1777
1778         put_device(xd->dev.parent);
1779
1780         kfree(xd->local_property_block);
1781         tb_property_free_dir(xd->remote_properties);
1782         ida_destroy(&xd->out_hopids);
1783         ida_destroy(&xd->in_hopids);
1784         ida_destroy(&xd->service_ids);
1785
1786         kfree(xd->local_uuid);
1787         kfree(xd->remote_uuid);
1788         kfree(xd->device_name);
1789         kfree(xd->vendor_name);
1790         kfree(xd);
1791 }
1792
1793 static void start_handshake(struct tb_xdomain *xd)
1794 {
1795         xd->state = XDOMAIN_STATE_INIT;
1796         queue_delayed_work(xd->tb->wq, &xd->state_work,
1797                            msecs_to_jiffies(XDOMAIN_SHORT_TIMEOUT));
1798 }
1799
1800 static void stop_handshake(struct tb_xdomain *xd)
1801 {
1802         cancel_delayed_work_sync(&xd->properties_changed_work);
1803         cancel_delayed_work_sync(&xd->state_work);
1804         xd->properties_changed_retries = 0;
1805         xd->state_retries = 0;
1806 }
1807
1808 static int __maybe_unused tb_xdomain_suspend(struct device *dev)
1809 {
1810         stop_handshake(tb_to_xdomain(dev));
1811         return 0;
1812 }
1813
1814 static int __maybe_unused tb_xdomain_resume(struct device *dev)
1815 {
1816         start_handshake(tb_to_xdomain(dev));
1817         return 0;
1818 }
1819
1820 static const struct dev_pm_ops tb_xdomain_pm_ops = {
1821         SET_SYSTEM_SLEEP_PM_OPS(tb_xdomain_suspend, tb_xdomain_resume)
1822 };
1823
1824 struct device_type tb_xdomain_type = {
1825         .name = "thunderbolt_xdomain",
1826         .release = tb_xdomain_release,
1827         .pm = &tb_xdomain_pm_ops,
1828 };
1829 EXPORT_SYMBOL_GPL(tb_xdomain_type);
1830
1831 /**
1832  * tb_xdomain_alloc() - Allocate new XDomain object
1833  * @tb: Domain where the XDomain belongs
1834  * @parent: Parent device (the switch through the connection to the
1835  *          other domain is reached).
1836  * @route: Route string used to reach the other domain
1837  * @local_uuid: Our local domain UUID
1838  * @remote_uuid: UUID of the other domain (optional)
1839  *
1840  * Allocates new XDomain structure and returns pointer to that. The
1841  * object must be released by calling tb_xdomain_put().
1842  */
1843 struct tb_xdomain *tb_xdomain_alloc(struct tb *tb, struct device *parent,
1844                                     u64 route, const uuid_t *local_uuid,
1845                                     const uuid_t *remote_uuid)
1846 {
1847         struct tb_switch *parent_sw = tb_to_switch(parent);
1848         struct tb_xdomain *xd;
1849         struct tb_port *down;
1850
1851         /* Make sure the downstream domain is accessible */
1852         down = tb_port_at(route, parent_sw);
1853         tb_port_unlock(down);
1854
1855         xd = kzalloc(sizeof(*xd), GFP_KERNEL);
1856         if (!xd)
1857                 return NULL;
1858
1859         xd->tb = tb;
1860         xd->route = route;
1861         xd->local_max_hopid = down->config.max_in_hop_id;
1862         ida_init(&xd->service_ids);
1863         ida_init(&xd->in_hopids);
1864         ida_init(&xd->out_hopids);
1865         mutex_init(&xd->lock);
1866         INIT_DELAYED_WORK(&xd->state_work, tb_xdomain_state_work);
1867         INIT_DELAYED_WORK(&xd->properties_changed_work,
1868                           tb_xdomain_properties_changed);
1869
1870         xd->local_uuid = kmemdup(local_uuid, sizeof(uuid_t), GFP_KERNEL);
1871         if (!xd->local_uuid)
1872                 goto err_free;
1873
1874         if (remote_uuid) {
1875                 xd->remote_uuid = kmemdup(remote_uuid, sizeof(uuid_t),
1876                                           GFP_KERNEL);
1877                 if (!xd->remote_uuid)
1878                         goto err_free_local_uuid;
1879         } else {
1880                 xd->needs_uuid = true;
1881                 xd->bonding_possible = !!down->dual_link_port;
1882         }
1883
1884         device_initialize(&xd->dev);
1885         xd->dev.parent = get_device(parent);
1886         xd->dev.bus = &tb_bus_type;
1887         xd->dev.type = &tb_xdomain_type;
1888         xd->dev.groups = xdomain_attr_groups;
1889         dev_set_name(&xd->dev, "%u-%llx", tb->index, route);
1890
1891         dev_dbg(&xd->dev, "local UUID %pUb\n", local_uuid);
1892         if (remote_uuid)
1893                 dev_dbg(&xd->dev, "remote UUID %pUb\n", remote_uuid);
1894
1895         /*
1896          * This keeps the DMA powered on as long as we have active
1897          * connection to another host.
1898          */
1899         pm_runtime_set_active(&xd->dev);
1900         pm_runtime_get_noresume(&xd->dev);
1901         pm_runtime_enable(&xd->dev);
1902
1903         return xd;
1904
1905 err_free_local_uuid:
1906         kfree(xd->local_uuid);
1907 err_free:
1908         kfree(xd);
1909
1910         return NULL;
1911 }
1912
1913 /**
1914  * tb_xdomain_add() - Add XDomain to the bus
1915  * @xd: XDomain to add
1916  *
1917  * This function starts XDomain discovery protocol handshake and
1918  * eventually adds the XDomain to the bus. After calling this function
1919  * the caller needs to call tb_xdomain_remove() in order to remove and
1920  * release the object regardless whether the handshake succeeded or not.
1921  */
1922 void tb_xdomain_add(struct tb_xdomain *xd)
1923 {
1924         /* Start exchanging properties with the other host */
1925         start_handshake(xd);
1926 }
1927
1928 static int unregister_service(struct device *dev, void *data)
1929 {
1930         device_unregister(dev);
1931         return 0;
1932 }
1933
1934 /**
1935  * tb_xdomain_remove() - Remove XDomain from the bus
1936  * @xd: XDomain to remove
1937  *
1938  * This will stop all ongoing configuration work and remove the XDomain
1939  * along with any services from the bus. When the last reference to @xd
1940  * is released the object will be released as well.
1941  */
1942 void tb_xdomain_remove(struct tb_xdomain *xd)
1943 {
1944         tb_xdomain_debugfs_remove(xd);
1945
1946         stop_handshake(xd);
1947
1948         device_for_each_child_reverse(&xd->dev, xd, unregister_service);
1949
1950         /*
1951          * Undo runtime PM here explicitly because it is possible that
1952          * the XDomain was never added to the bus and thus device_del()
1953          * is not called for it (device_del() would handle this otherwise).
1954          */
1955         pm_runtime_disable(&xd->dev);
1956         pm_runtime_put_noidle(&xd->dev);
1957         pm_runtime_set_suspended(&xd->dev);
1958
1959         if (!device_is_registered(&xd->dev)) {
1960                 put_device(&xd->dev);
1961         } else {
1962                 dev_info(&xd->dev, "host disconnected\n");
1963                 device_unregister(&xd->dev);
1964         }
1965 }
1966
1967 /**
1968  * tb_xdomain_lane_bonding_enable() - Enable lane bonding on XDomain
1969  * @xd: XDomain connection
1970  *
1971  * Lane bonding is disabled by default for XDomains. This function tries
1972  * to enable bonding by first enabling the port and waiting for the CL0
1973  * state.
1974  *
1975  * Return: %0 in case of success and negative errno in case of error.
1976  */
1977 int tb_xdomain_lane_bonding_enable(struct tb_xdomain *xd)
1978 {
1979         struct tb_port *port;
1980         int ret;
1981
1982         port = tb_port_at(xd->route, tb_xdomain_parent(xd));
1983         if (!port->dual_link_port)
1984                 return -ENODEV;
1985
1986         ret = tb_port_enable(port->dual_link_port);
1987         if (ret)
1988                 return ret;
1989
1990         ret = tb_wait_for_port(port->dual_link_port, true);
1991         if (ret < 0)
1992                 return ret;
1993         if (!ret)
1994                 return -ENOTCONN;
1995
1996         ret = tb_port_lane_bonding_enable(port);
1997         if (ret) {
1998                 tb_port_warn(port, "failed to enable lane bonding\n");
1999                 return ret;
2000         }
2001
2002         ret = tb_port_wait_for_link_width(port, 2, XDOMAIN_BONDING_TIMEOUT);
2003         if (ret) {
2004                 tb_port_warn(port, "failed to enable lane bonding\n");
2005                 return ret;
2006         }
2007
2008         tb_port_update_credits(port);
2009         tb_xdomain_update_link_attributes(xd);
2010
2011         dev_dbg(&xd->dev, "lane bonding enabled\n");
2012         return 0;
2013 }
2014 EXPORT_SYMBOL_GPL(tb_xdomain_lane_bonding_enable);
2015
2016 /**
2017  * tb_xdomain_lane_bonding_disable() - Disable lane bonding
2018  * @xd: XDomain connection
2019  *
2020  * Lane bonding is disabled by default for XDomains. If bonding has been
2021  * enabled, this function can be used to disable it.
2022  */
2023 void tb_xdomain_lane_bonding_disable(struct tb_xdomain *xd)
2024 {
2025         struct tb_port *port;
2026
2027         port = tb_port_at(xd->route, tb_xdomain_parent(xd));
2028         if (port->dual_link_port) {
2029                 tb_port_lane_bonding_disable(port);
2030                 if (tb_port_wait_for_link_width(port, 1, 100) == -ETIMEDOUT)
2031                         tb_port_warn(port, "timeout disabling lane bonding\n");
2032                 tb_port_disable(port->dual_link_port);
2033                 tb_port_update_credits(port);
2034                 tb_xdomain_update_link_attributes(xd);
2035
2036                 dev_dbg(&xd->dev, "lane bonding disabled\n");
2037         }
2038 }
2039 EXPORT_SYMBOL_GPL(tb_xdomain_lane_bonding_disable);
2040
2041 /**
2042  * tb_xdomain_alloc_in_hopid() - Allocate input HopID for tunneling
2043  * @xd: XDomain connection
2044  * @hopid: Preferred HopID or %-1 for next available
2045  *
2046  * Returns allocated HopID or negative errno. Specifically returns
2047  * %-ENOSPC if there are no more available HopIDs. Returned HopID is
2048  * guaranteed to be within range supported by the input lane adapter.
2049  * Call tb_xdomain_release_in_hopid() to release the allocated HopID.
2050  */
2051 int tb_xdomain_alloc_in_hopid(struct tb_xdomain *xd, int hopid)
2052 {
2053         if (hopid < 0)
2054                 hopid = TB_PATH_MIN_HOPID;
2055         if (hopid < TB_PATH_MIN_HOPID || hopid > xd->local_max_hopid)
2056                 return -EINVAL;
2057
2058         return ida_alloc_range(&xd->in_hopids, hopid, xd->local_max_hopid,
2059                                GFP_KERNEL);
2060 }
2061 EXPORT_SYMBOL_GPL(tb_xdomain_alloc_in_hopid);
2062
2063 /**
2064  * tb_xdomain_alloc_out_hopid() - Allocate output HopID for tunneling
2065  * @xd: XDomain connection
2066  * @hopid: Preferred HopID or %-1 for next available
2067  *
2068  * Returns allocated HopID or negative errno. Specifically returns
2069  * %-ENOSPC if there are no more available HopIDs. Returned HopID is
2070  * guaranteed to be within range supported by the output lane adapter.
2071  * Call tb_xdomain_release_in_hopid() to release the allocated HopID.
2072  */
2073 int tb_xdomain_alloc_out_hopid(struct tb_xdomain *xd, int hopid)
2074 {
2075         if (hopid < 0)
2076                 hopid = TB_PATH_MIN_HOPID;
2077         if (hopid < TB_PATH_MIN_HOPID || hopid > xd->remote_max_hopid)
2078                 return -EINVAL;
2079
2080         return ida_alloc_range(&xd->out_hopids, hopid, xd->remote_max_hopid,
2081                                GFP_KERNEL);
2082 }
2083 EXPORT_SYMBOL_GPL(tb_xdomain_alloc_out_hopid);
2084
2085 /**
2086  * tb_xdomain_release_in_hopid() - Release input HopID
2087  * @xd: XDomain connection
2088  * @hopid: HopID to release
2089  */
2090 void tb_xdomain_release_in_hopid(struct tb_xdomain *xd, int hopid)
2091 {
2092         ida_free(&xd->in_hopids, hopid);
2093 }
2094 EXPORT_SYMBOL_GPL(tb_xdomain_release_in_hopid);
2095
2096 /**
2097  * tb_xdomain_release_out_hopid() - Release output HopID
2098  * @xd: XDomain connection
2099  * @hopid: HopID to release
2100  */
2101 void tb_xdomain_release_out_hopid(struct tb_xdomain *xd, int hopid)
2102 {
2103         ida_free(&xd->out_hopids, hopid);
2104 }
2105 EXPORT_SYMBOL_GPL(tb_xdomain_release_out_hopid);
2106
2107 /**
2108  * tb_xdomain_enable_paths() - Enable DMA paths for XDomain connection
2109  * @xd: XDomain connection
2110  * @transmit_path: HopID we are using to send out packets
2111  * @transmit_ring: DMA ring used to send out packets
2112  * @receive_path: HopID the other end is using to send packets to us
2113  * @receive_ring: DMA ring used to receive packets from @receive_path
2114  *
2115  * The function enables DMA paths accordingly so that after successful
2116  * return the caller can send and receive packets using high-speed DMA
2117  * path. If a transmit or receive path is not needed, pass %-1 for those
2118  * parameters.
2119  *
2120  * Return: %0 in case of success and negative errno in case of error
2121  */
2122 int tb_xdomain_enable_paths(struct tb_xdomain *xd, int transmit_path,
2123                             int transmit_ring, int receive_path,
2124                             int receive_ring)
2125 {
2126         return tb_domain_approve_xdomain_paths(xd->tb, xd, transmit_path,
2127                                                transmit_ring, receive_path,
2128                                                receive_ring);
2129 }
2130 EXPORT_SYMBOL_GPL(tb_xdomain_enable_paths);
2131
2132 /**
2133  * tb_xdomain_disable_paths() - Disable DMA paths for XDomain connection
2134  * @xd: XDomain connection
2135  * @transmit_path: HopID we are using to send out packets
2136  * @transmit_ring: DMA ring used to send out packets
2137  * @receive_path: HopID the other end is using to send packets to us
2138  * @receive_ring: DMA ring used to receive packets from @receive_path
2139  *
2140  * This does the opposite of tb_xdomain_enable_paths(). After call to
2141  * this the caller is not expected to use the rings anymore. Passing %-1
2142  * as path/ring parameter means don't care. Normally the callers should
2143  * pass the same values here as they do when paths are enabled.
2144  *
2145  * Return: %0 in case of success and negative errno in case of error
2146  */
2147 int tb_xdomain_disable_paths(struct tb_xdomain *xd, int transmit_path,
2148                              int transmit_ring, int receive_path,
2149                              int receive_ring)
2150 {
2151         return tb_domain_disconnect_xdomain_paths(xd->tb, xd, transmit_path,
2152                                                   transmit_ring, receive_path,
2153                                                   receive_ring);
2154 }
2155 EXPORT_SYMBOL_GPL(tb_xdomain_disable_paths);
2156
2157 struct tb_xdomain_lookup {
2158         const uuid_t *uuid;
2159         u8 link;
2160         u8 depth;
2161         u64 route;
2162 };
2163
2164 static struct tb_xdomain *switch_find_xdomain(struct tb_switch *sw,
2165         const struct tb_xdomain_lookup *lookup)
2166 {
2167         struct tb_port *port;
2168
2169         tb_switch_for_each_port(sw, port) {
2170                 struct tb_xdomain *xd;
2171
2172                 if (port->xdomain) {
2173                         xd = port->xdomain;
2174
2175                         if (lookup->uuid) {
2176                                 if (xd->remote_uuid &&
2177                                     uuid_equal(xd->remote_uuid, lookup->uuid))
2178                                         return xd;
2179                         } else {
2180                                 if (lookup->link && lookup->link == xd->link &&
2181                                     lookup->depth == xd->depth)
2182                                         return xd;
2183                                 if (lookup->route && lookup->route == xd->route)
2184                                         return xd;
2185                         }
2186                 } else if (tb_port_has_remote(port)) {
2187                         xd = switch_find_xdomain(port->remote->sw, lookup);
2188                         if (xd)
2189                                 return xd;
2190                 }
2191         }
2192
2193         return NULL;
2194 }
2195
2196 /**
2197  * tb_xdomain_find_by_uuid() - Find an XDomain by UUID
2198  * @tb: Domain where the XDomain belongs to
2199  * @uuid: UUID to look for
2200  *
2201  * Finds XDomain by walking through the Thunderbolt topology below @tb.
2202  * The returned XDomain will have its reference count increased so the
2203  * caller needs to call tb_xdomain_put() when it is done with the
2204  * object.
2205  *
2206  * This will find all XDomains including the ones that are not yet added
2207  * to the bus (handshake is still in progress).
2208  *
2209  * The caller needs to hold @tb->lock.
2210  */
2211 struct tb_xdomain *tb_xdomain_find_by_uuid(struct tb *tb, const uuid_t *uuid)
2212 {
2213         struct tb_xdomain_lookup lookup;
2214         struct tb_xdomain *xd;
2215
2216         memset(&lookup, 0, sizeof(lookup));
2217         lookup.uuid = uuid;
2218
2219         xd = switch_find_xdomain(tb->root_switch, &lookup);
2220         return tb_xdomain_get(xd);
2221 }
2222 EXPORT_SYMBOL_GPL(tb_xdomain_find_by_uuid);
2223
2224 /**
2225  * tb_xdomain_find_by_link_depth() - Find an XDomain by link and depth
2226  * @tb: Domain where the XDomain belongs to
2227  * @link: Root switch link number
2228  * @depth: Depth in the link
2229  *
2230  * Finds XDomain by walking through the Thunderbolt topology below @tb.
2231  * The returned XDomain will have its reference count increased so the
2232  * caller needs to call tb_xdomain_put() when it is done with the
2233  * object.
2234  *
2235  * This will find all XDomains including the ones that are not yet added
2236  * to the bus (handshake is still in progress).
2237  *
2238  * The caller needs to hold @tb->lock.
2239  */
2240 struct tb_xdomain *tb_xdomain_find_by_link_depth(struct tb *tb, u8 link,
2241                                                  u8 depth)
2242 {
2243         struct tb_xdomain_lookup lookup;
2244         struct tb_xdomain *xd;
2245
2246         memset(&lookup, 0, sizeof(lookup));
2247         lookup.link = link;
2248         lookup.depth = depth;
2249
2250         xd = switch_find_xdomain(tb->root_switch, &lookup);
2251         return tb_xdomain_get(xd);
2252 }
2253
2254 /**
2255  * tb_xdomain_find_by_route() - Find an XDomain by route string
2256  * @tb: Domain where the XDomain belongs to
2257  * @route: XDomain route string
2258  *
2259  * Finds XDomain by walking through the Thunderbolt topology below @tb.
2260  * The returned XDomain will have its reference count increased so the
2261  * caller needs to call tb_xdomain_put() when it is done with the
2262  * object.
2263  *
2264  * This will find all XDomains including the ones that are not yet added
2265  * to the bus (handshake is still in progress).
2266  *
2267  * The caller needs to hold @tb->lock.
2268  */
2269 struct tb_xdomain *tb_xdomain_find_by_route(struct tb *tb, u64 route)
2270 {
2271         struct tb_xdomain_lookup lookup;
2272         struct tb_xdomain *xd;
2273
2274         memset(&lookup, 0, sizeof(lookup));
2275         lookup.route = route;
2276
2277         xd = switch_find_xdomain(tb->root_switch, &lookup);
2278         return tb_xdomain_get(xd);
2279 }
2280 EXPORT_SYMBOL_GPL(tb_xdomain_find_by_route);
2281
2282 bool tb_xdomain_handle_request(struct tb *tb, enum tb_cfg_pkg_type type,
2283                                const void *buf, size_t size)
2284 {
2285         const struct tb_protocol_handler *handler, *tmp;
2286         const struct tb_xdp_header *hdr = buf;
2287         unsigned int length;
2288         int ret = 0;
2289
2290         /* We expect the packet is at least size of the header */
2291         length = hdr->xd_hdr.length_sn & TB_XDOMAIN_LENGTH_MASK;
2292         if (length != size / 4 - sizeof(hdr->xd_hdr) / 4)
2293                 return true;
2294         if (length < sizeof(*hdr) / 4 - sizeof(hdr->xd_hdr) / 4)
2295                 return true;
2296
2297         /*
2298          * Handle XDomain discovery protocol packets directly here. For
2299          * other protocols (based on their UUID) we call registered
2300          * handlers in turn.
2301          */
2302         if (uuid_equal(&hdr->uuid, &tb_xdp_uuid)) {
2303                 if (type == TB_CFG_PKG_XDOMAIN_REQ)
2304                         return tb_xdp_schedule_request(tb, hdr, size);
2305                 return false;
2306         }
2307
2308         mutex_lock(&xdomain_lock);
2309         list_for_each_entry_safe(handler, tmp, &protocol_handlers, list) {
2310                 if (!uuid_equal(&hdr->uuid, handler->uuid))
2311                         continue;
2312
2313                 mutex_unlock(&xdomain_lock);
2314                 ret = handler->callback(buf, size, handler->data);
2315                 mutex_lock(&xdomain_lock);
2316
2317                 if (ret)
2318                         break;
2319         }
2320         mutex_unlock(&xdomain_lock);
2321
2322         return ret > 0;
2323 }
2324
2325 static int update_xdomain(struct device *dev, void *data)
2326 {
2327         struct tb_xdomain *xd;
2328
2329         xd = tb_to_xdomain(dev);
2330         if (xd) {
2331                 queue_delayed_work(xd->tb->wq, &xd->properties_changed_work,
2332                                    msecs_to_jiffies(50));
2333         }
2334
2335         return 0;
2336 }
2337
2338 static void update_all_xdomains(void)
2339 {
2340         bus_for_each_dev(&tb_bus_type, NULL, NULL, update_xdomain);
2341 }
2342
2343 static bool remove_directory(const char *key, const struct tb_property_dir *dir)
2344 {
2345         struct tb_property *p;
2346
2347         p = tb_property_find(xdomain_property_dir, key,
2348                              TB_PROPERTY_TYPE_DIRECTORY);
2349         if (p && p->value.dir == dir) {
2350                 tb_property_remove(p);
2351                 return true;
2352         }
2353         return false;
2354 }
2355
2356 /**
2357  * tb_register_property_dir() - Register property directory to the host
2358  * @key: Key (name) of the directory to add
2359  * @dir: Directory to add
2360  *
2361  * Service drivers can use this function to add new property directory
2362  * to the host available properties. The other connected hosts are
2363  * notified so they can re-read properties of this host if they are
2364  * interested.
2365  *
2366  * Return: %0 on success and negative errno on failure
2367  */
2368 int tb_register_property_dir(const char *key, struct tb_property_dir *dir)
2369 {
2370         int ret;
2371
2372         if (WARN_ON(!xdomain_property_dir))
2373                 return -EAGAIN;
2374
2375         if (!key || strlen(key) > 8)
2376                 return -EINVAL;
2377
2378         mutex_lock(&xdomain_lock);
2379         if (tb_property_find(xdomain_property_dir, key,
2380                              TB_PROPERTY_TYPE_DIRECTORY)) {
2381                 ret = -EEXIST;
2382                 goto err_unlock;
2383         }
2384
2385         ret = tb_property_add_dir(xdomain_property_dir, key, dir);
2386         if (ret)
2387                 goto err_unlock;
2388
2389         xdomain_property_block_gen++;
2390
2391         mutex_unlock(&xdomain_lock);
2392         update_all_xdomains();
2393         return 0;
2394
2395 err_unlock:
2396         mutex_unlock(&xdomain_lock);
2397         return ret;
2398 }
2399 EXPORT_SYMBOL_GPL(tb_register_property_dir);
2400
2401 /**
2402  * tb_unregister_property_dir() - Removes property directory from host
2403  * @key: Key (name) of the directory
2404  * @dir: Directory to remove
2405  *
2406  * This will remove the existing directory from this host and notify the
2407  * connected hosts about the change.
2408  */
2409 void tb_unregister_property_dir(const char *key, struct tb_property_dir *dir)
2410 {
2411         int ret = 0;
2412
2413         mutex_lock(&xdomain_lock);
2414         if (remove_directory(key, dir))
2415                 xdomain_property_block_gen++;
2416         mutex_unlock(&xdomain_lock);
2417
2418         if (!ret)
2419                 update_all_xdomains();
2420 }
2421 EXPORT_SYMBOL_GPL(tb_unregister_property_dir);
2422
2423 int tb_xdomain_init(void)
2424 {
2425         xdomain_property_dir = tb_property_create_dir(NULL);
2426         if (!xdomain_property_dir)
2427                 return -ENOMEM;
2428
2429         /*
2430          * Initialize standard set of properties without any service
2431          * directories. Those will be added by service drivers
2432          * themselves when they are loaded.
2433          *
2434          * Rest of the properties are filled dynamically based on these
2435          * when the P2P connection is made.
2436          */
2437         tb_property_add_immediate(xdomain_property_dir, "vendorid",
2438                                   PCI_VENDOR_ID_INTEL);
2439         tb_property_add_text(xdomain_property_dir, "vendorid", "Intel Corp.");
2440         tb_property_add_immediate(xdomain_property_dir, "deviceid", 0x1);
2441         tb_property_add_immediate(xdomain_property_dir, "devicerv", 0x80000100);
2442
2443         xdomain_property_block_gen = get_random_u32();
2444         return 0;
2445 }
2446
2447 void tb_xdomain_exit(void)
2448 {
2449         tb_property_free_dir(xdomain_property_dir);
2450 }