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/utsname.h>
  17 #include <linux/uuid.h>
  18 #include <linux/workqueue.h>
  19
  20 #include "tb.h"
  21
  22 #define XDOMAIN_SHORT_TIMEOUT                   100     /* ms */
  23 #define XDOMAIN_DEFAULT_TIMEOUT                 1000    /* ms */
  24 #define XDOMAIN_BONDING_TIMEOUT                 10000   /* ms */
  25 #define XDOMAIN_RETRIES                         10
  26 #define XDOMAIN_DEFAULT_MAX_HOPID               15
  27
  28 enum {
  29         XDOMAIN_STATE_INIT,
  30         XDOMAIN_STATE_UUID,
  31         XDOMAIN_STATE_LINK_STATUS,
  32         XDOMAIN_STATE_LINK_STATE_CHANGE,
  33         XDOMAIN_STATE_LINK_STATUS2,
  34         XDOMAIN_STATE_BONDING_UUID_LOW,
  35         XDOMAIN_STATE_BONDING_UUID_HIGH,
  36         XDOMAIN_STATE_PROPERTIES,
  37         XDOMAIN_STATE_ENUMERATED,
  38         XDOMAIN_STATE_ERROR,
  39 };
  40
  41 static const char * const state_names[] = {
  42         [XDOMAIN_STATE_INIT] = "INIT",
  43         [XDOMAIN_STATE_UUID] = "UUID",
  44         [XDOMAIN_STATE_LINK_STATUS] = "LINK_STATUS",
  45         [XDOMAIN_STATE_LINK_STATE_CHANGE] = "LINK_STATE_CHANGE",
  46         [XDOMAIN_STATE_LINK_STATUS2] = "LINK_STATUS2",
  47         [XDOMAIN_STATE_BONDING_UUID_LOW] = "BONDING_UUID_LOW",
  48         [XDOMAIN_STATE_BONDING_UUID_HIGH] = "BONDING_UUID_HIGH",
  49         [XDOMAIN_STATE_PROPERTIES] = "PROPERTIES",
  50         [XDOMAIN_STATE_ENUMERATED] = "ENUMERATED",
  51         [XDOMAIN_STATE_ERROR] = "ERROR",
  52 };
  53
  54 struct xdomain_request_work {
  55         struct work_struct work;
  56         struct tb_xdp_header *pkg;
  57         struct tb *tb;
  58 };
  59
  60 static bool tb_xdomain_enabled = true;
  61 module_param_named(xdomain, tb_xdomain_enabled, bool, 0444);
  62 MODULE_PARM_DESC(xdomain, "allow XDomain protocol (default: true)");
  63
  64 /*
  65  * Serializes access to the properties and protocol handlers below. If
  66  * you need to take both this lock and the struct tb_xdomain lock, take
  67  * this one first.
  68  */
  69 static DEFINE_MUTEX(xdomain_lock);
  70
  71 /* Properties exposed to the remote domains */
  72 static struct tb_property_dir *xdomain_property_dir;
  73 static u32 xdomain_property_block_gen;
  74
  75 /* Additional protocol handlers */
  76 static LIST_HEAD(protocol_handlers);
  77
  78 /* UUID for XDomain discovery protocol: b638d70e-42ff-40bb-97c2-90e2c0b2ff07 */
  79 static const uuid_t tb_xdp_uuid =
  80         UUID_INIT(0xb638d70e, 0x42ff, 0x40bb,
  81                   0x97, 0xc2, 0x90, 0xe2, 0xc0, 0xb2, 0xff, 0x07);
  82
  83 bool tb_is_xdomain_enabled(void)
  84 {
  85         return tb_xdomain_enabled && tb_acpi_is_xdomain_allowed();
  86 }
  87
  88 static bool tb_xdomain_match(const struct tb_cfg_request *req,
  89                              const struct ctl_pkg *pkg)
  90 {
  91         switch (pkg->frame.eof) {
  92         case TB_CFG_PKG_ERROR:
  93                 return true;
  94
  95         case TB_CFG_PKG_XDOMAIN_RESP: {
  96                 const struct tb_xdp_header *res_hdr = pkg->buffer;
  97                 const struct tb_xdp_header *req_hdr = req->request;
  98
  99                 if (pkg->frame.size < req->response_size / 4)
 100                         return false;
 101
 102                 /* Make sure route matches */
 103                 if ((res_hdr->xd_hdr.route_hi & ~BIT(31)) !=
 104                      req_hdr->xd_hdr.route_hi)
 105                         return false;
 106                 if ((res_hdr->xd_hdr.route_lo) != req_hdr->xd_hdr.route_lo)
 107                         return false;
 108
 109                 /* Check that the XDomain protocol matches */
 110                 if (!uuid_equal(&res_hdr->uuid, &req_hdr->uuid))
 111                         return false;
 112
 113                 return true;
 114         }
 115
 116         default:
 117                 return false;
 118         }
 119 }
 120
 121 static bool tb_xdomain_copy(struct tb_cfg_request *req,
 122                             const struct ctl_pkg *pkg)
 123 {
 124         memcpy(req->response, pkg->buffer, req->response_size);
 125         req->result.err = 0;
 126         return true;
 127 }
 128
 129 static void response_ready(void *data)
 130 {
 131         tb_cfg_request_put(data);
 132 }
 133
 134 static int __tb_xdomain_response(struct tb_ctl *ctl, const void *response,
 135                                  size_t size, enum tb_cfg_pkg_type type)
 136 {
 137         struct tb_cfg_request *req;
 138
 139         req = tb_cfg_request_alloc();
 140         if (!req)
 141                 return -ENOMEM;
 142
 143         req->match = tb_xdomain_match;
 144         req->copy = tb_xdomain_copy;
 145         req->request = response;
 146         req->request_size = size;
 147         req->request_type = type;
 148
 149         return tb_cfg_request(ctl, req, response_ready, req);
 150 }
 151
 152 /**
 153  * tb_xdomain_response() - Send a XDomain response message
 154  * @xd: XDomain to send the message
 155  * @response: Response to send
 156  * @size: Size of the response
 157  * @type: PDF type of the response
 158  *
 159  * This can be used to send a XDomain response message to the other
 160  * domain. No response for the message is expected.
 161  *
 162  * Return: %0 in case of success and negative errno in case of failure
 163  */
 164 int tb_xdomain_response(struct tb_xdomain *xd, const void *response,
 165                         size_t size, enum tb_cfg_pkg_type type)
 166 {
 167         return __tb_xdomain_response(xd->tb->ctl, response, size, type);
 168 }
 169 EXPORT_SYMBOL_GPL(tb_xdomain_response);
 170
 171 static int __tb_xdomain_request(struct tb_ctl *ctl, const void *request,
 172         size_t request_size, enum tb_cfg_pkg_type request_type, void *response,
 173         size_t response_size, enum tb_cfg_pkg_type response_type,
 174         unsigned int timeout_msec)
 175 {
 176         struct tb_cfg_request *req;
 177         struct tb_cfg_result res;
 178
 179         req = tb_cfg_request_alloc();
 180         if (!req)
 181                 return -ENOMEM;
 182
 183         req->match = tb_xdomain_match;
 184         req->copy = tb_xdomain_copy;
 185         req->request = request;
 186         req->request_size = request_size;
 187         req->request_type = request_type;
 188         req->response = response;
 189         req->response_size = response_size;
 190         req->response_type = response_type;
 191
 192         res = tb_cfg_request_sync(ctl, req, timeout_msec);
 193
 194         tb_cfg_request_put(req);
 195
 196         return res.err == 1 ? -EIO : res.err;
 197 }
 198
 199 /**
 200  * tb_xdomain_request() - Send a XDomain request
 201  * @xd: XDomain to send the request
 202  * @request: Request to send
 203  * @request_size: Size of the request in bytes
 204  * @request_type: PDF type of the request
 205  * @response: Response is copied here
 206  * @response_size: Expected size of the response in bytes
 207  * @response_type: Expected PDF type of the response
 208  * @timeout_msec: Timeout in milliseconds to wait for the response
 209  *
 210  * This function can be used to send XDomain control channel messages to
 211  * the other domain. The function waits until the response is received
 212  * or when timeout triggers. Whichever comes first.
 213  *
 214  * Return: %0 in case of success and negative errno in case of failure
 215  */
 216 int tb_xdomain_request(struct tb_xdomain *xd, const void *request,
 217         size_t request_size, enum tb_cfg_pkg_type request_type,
 218         void *response, size_t response_size,
 219         enum tb_cfg_pkg_type response_type, unsigned int timeout_msec)
 220 {
 221         return __tb_xdomain_request(xd->tb->ctl, request, request_size,
 222                                     request_type, response, response_size,
 223                                     response_type, timeout_msec);
 224 }
 225 EXPORT_SYMBOL_GPL(tb_xdomain_request);
 226
 227 static inline void tb_xdp_fill_header(struct tb_xdp_header *hdr, u64 route,
 228         u8 sequence, enum tb_xdp_type type, size_t size)
 229 {
 230         u32 length_sn;
 231
 232         length_sn = (size - sizeof(hdr->xd_hdr)) / 4;
 233         length_sn |= (sequence << TB_XDOMAIN_SN_SHIFT) & TB_XDOMAIN_SN_MASK;
 234
 235         hdr->xd_hdr.route_hi = upper_32_bits(route);
 236         hdr->xd_hdr.route_lo = lower_32_bits(route);
 237         hdr->xd_hdr.length_sn = length_sn;
 238         hdr->type = type;
 239         memcpy(&hdr->uuid, &tb_xdp_uuid, sizeof(tb_xdp_uuid));
 240 }
 241
 242 static int tb_xdp_handle_error(const struct tb_xdp_error_response *res)
 243 {
 244         if (res->hdr.type != ERROR_RESPONSE)
 245                 return 0;
 246
 247         switch (res->error) {
 248         case ERROR_UNKNOWN_PACKET:
 249         case ERROR_UNKNOWN_DOMAIN:
 250                 return -EIO;
 251         case ERROR_NOT_SUPPORTED:
 252                 return -ENOTSUPP;
 253         case ERROR_NOT_READY:
 254                 return -EAGAIN;
 255         default:
 256                 break;
 257         }
 258
 259         return 0;
 260 }
 261
 262 static int tb_xdp_uuid_request(struct tb_ctl *ctl, u64 route, int retry,
 263                                uuid_t *uuid, u64 *remote_route)
 264 {
 265         struct tb_xdp_uuid_response res;
 266         struct tb_xdp_uuid req;
 267         int ret;
 268
 269         memset(&req, 0, sizeof(req));
 270         tb_xdp_fill_header(&req.hdr, route, retry % 4, UUID_REQUEST,
 271                            sizeof(req));
 272
 273         memset(&res, 0, sizeof(res));
 274         ret = __tb_xdomain_request(ctl, &req, sizeof(req),
 275                                    TB_CFG_PKG_XDOMAIN_REQ, &res, sizeof(res),
 276                                    TB_CFG_PKG_XDOMAIN_RESP,
 277                                    XDOMAIN_DEFAULT_TIMEOUT);
 278         if (ret)
 279                 return ret;
 280
 281         ret = tb_xdp_handle_error(&res.err);
 282         if (ret)
 283                 return ret;
 284
 285         uuid_copy(uuid, &res.src_uuid);
 286         *remote_route = (u64)res.src_route_hi << 32 | res.src_route_lo;
 287
 288         return 0;
 289 }
 290
 291 static int tb_xdp_uuid_response(struct tb_ctl *ctl, u64 route, u8 sequence,
 292                                 const uuid_t *uuid)
 293 {
 294         struct tb_xdp_uuid_response res;
 295
 296         memset(&res, 0, sizeof(res));
 297         tb_xdp_fill_header(&res.hdr, route, sequence, UUID_RESPONSE,
 298                            sizeof(res));
 299
 300         uuid_copy(&res.src_uuid, uuid);
 301         res.src_route_hi = upper_32_bits(route);
 302         res.src_route_lo = lower_32_bits(route);
 303
 304         return __tb_xdomain_response(ctl, &res, sizeof(res),
 305                                      TB_CFG_PKG_XDOMAIN_RESP);
 306 }
 307
 308 static int tb_xdp_error_response(struct tb_ctl *ctl, u64 route, u8 sequence,
 309                                  enum tb_xdp_error error)
 310 {
 311         struct tb_xdp_error_response res;
 312
 313         memset(&res, 0, sizeof(res));
 314         tb_xdp_fill_header(&res.hdr, route, sequence, ERROR_RESPONSE,
 315                            sizeof(res));
 316         res.error = error;
 317
 318         return __tb_xdomain_response(ctl, &res, sizeof(res),
 319                                      TB_CFG_PKG_XDOMAIN_RESP);
 320 }
 321
 322 static int tb_xdp_properties_request(struct tb_ctl *ctl, u64 route,
 323         const uuid_t *src_uuid, const uuid_t *dst_uuid, int retry,
 324         u32 **block, u32 *generation)
 325 {
 326         struct tb_xdp_properties_response *res;
 327         struct tb_xdp_properties req;
 328         u16 data_len, len;
 329         size_t total_size;
 330         u32 *data = NULL;
 331         int ret;
 332
 333         total_size = sizeof(*res) + TB_XDP_PROPERTIES_MAX_DATA_LENGTH * 4;
 334         res = kzalloc(total_size, GFP_KERNEL);
 335         if (!res)
 336                 return -ENOMEM;
 337
 338         memset(&req, 0, sizeof(req));
 339         tb_xdp_fill_header(&req.hdr, route, retry % 4, PROPERTIES_REQUEST,
 340                            sizeof(req));
 341         memcpy(&req.src_uuid, src_uuid, sizeof(*src_uuid));
 342         memcpy(&req.dst_uuid, dst_uuid, sizeof(*dst_uuid));
 343
 344         len = 0;
 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(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(struct device *dev, struct kobj_uevent_env *env)
 957 {
 958         struct tb_service *svc = container_of(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                 } else {
1182                         dev_dbg(&xd->dev, "failed to read remote UUID\n");
1183                 }
1184                 return ret;
1185         }
1186
1187         dev_dbg(&xd->dev, "got remote UUID %pUb\n", &uuid);
1188
1189         if (uuid_equal(&uuid, xd->local_uuid)) {
1190                 if (route == xd->route)
1191                         dev_dbg(&xd->dev, "loop back detected\n");
1192                 else
1193                         dev_dbg(&xd->dev, "intra-domain loop detected\n");
1194
1195                 /* Don't bond lanes automatically for loops */
1196                 xd->bonding_possible = false;
1197         }
1198
1199         /*
1200          * If the UUID is different, there is another domain connected
1201          * so mark this one unplugged and wait for the connection
1202          * manager to replace it.
1203          */
1204         if (xd->remote_uuid && !uuid_equal(&uuid, xd->remote_uuid)) {
1205                 dev_dbg(&xd->dev, "remote UUID is different, unplugging\n");
1206                 xd->is_unplugged = true;
1207                 return -ENODEV;
1208         }
1209
1210         /* First time fill in the missing UUID */
1211         if (!xd->remote_uuid) {
1212                 xd->remote_uuid = kmemdup(&uuid, sizeof(uuid_t), GFP_KERNEL);
1213                 if (!xd->remote_uuid)
1214                         return -ENOMEM;
1215         }
1216
1217         return 0;
1218 }
1219
1220 static int tb_xdomain_get_link_status(struct tb_xdomain *xd)
1221 {
1222         struct tb *tb = xd->tb;
1223         u8 slw, tlw, sls, tls;
1224         int ret;
1225
1226         dev_dbg(&xd->dev, "sending link state status request to %pUb\n",
1227                 xd->remote_uuid);
1228
1229         ret = tb_xdp_link_state_status_request(tb->ctl, xd->route,
1230                                                xd->state_retries, &slw, &tlw, &sls,
1231                                                &tls);
1232         if (ret) {
1233                 if (ret != -EOPNOTSUPP && xd->state_retries-- > 0) {
1234                         dev_dbg(&xd->dev,
1235                                 "failed to request remote link status, retrying\n");
1236                         return -EAGAIN;
1237                 }
1238                 dev_dbg(&xd->dev, "failed to receive remote link status\n");
1239                 return ret;
1240         }
1241
1242         dev_dbg(&xd->dev, "remote link supports width %#x speed %#x\n", slw, sls);
1243
1244         if (slw < LANE_ADP_CS_0_SUPPORTED_WIDTH_DUAL) {
1245                 dev_dbg(&xd->dev, "remote adapter is single lane only\n");
1246                 return -EOPNOTSUPP;
1247         }
1248
1249         return 0;
1250 }
1251
1252 static int tb_xdomain_link_state_change(struct tb_xdomain *xd,
1253                                         unsigned int width)
1254 {
1255         struct tb_switch *sw = tb_to_switch(xd->dev.parent);
1256         struct tb_port *port = tb_port_at(xd->route, sw);
1257         struct tb *tb = xd->tb;
1258         u8 tlw, tls;
1259         u32 val;
1260         int ret;
1261
1262         if (width == 2)
1263                 tlw = LANE_ADP_CS_1_TARGET_WIDTH_DUAL;
1264         else if (width == 1)
1265                 tlw = LANE_ADP_CS_1_TARGET_WIDTH_SINGLE;
1266         else
1267                 return -EINVAL;
1268
1269         /* Use the current target speed */
1270         ret = tb_port_read(port, &val, TB_CFG_PORT, port->cap_phy + LANE_ADP_CS_1, 1);
1271         if (ret)
1272                 return ret;
1273         tls = val & LANE_ADP_CS_1_TARGET_SPEED_MASK;
1274
1275         dev_dbg(&xd->dev, "sending link state change request with width %#x speed %#x\n",
1276                 tlw, tls);
1277
1278         ret = tb_xdp_link_state_change_request(tb->ctl, xd->route,
1279                                                xd->state_retries, tlw, tls);
1280         if (ret) {
1281                 if (ret != -EOPNOTSUPP && xd->state_retries-- > 0) {
1282                         dev_dbg(&xd->dev,
1283                                 "failed to change remote link state, retrying\n");
1284                         return -EAGAIN;
1285                 }
1286                 dev_err(&xd->dev, "failed request link state change, aborting\n");
1287                 return ret;
1288         }
1289
1290         dev_dbg(&xd->dev, "received link state change response\n");
1291         return 0;
1292 }
1293
1294 static int tb_xdomain_bond_lanes_uuid_high(struct tb_xdomain *xd)
1295 {
1296         struct tb_port *port;
1297         int ret, width;
1298
1299         if (xd->target_link_width == LANE_ADP_CS_1_TARGET_WIDTH_SINGLE) {
1300                 width = 1;
1301         } else if (xd->target_link_width == LANE_ADP_CS_1_TARGET_WIDTH_DUAL) {
1302                 width = 2;
1303         } else {
1304                 if (xd->state_retries-- > 0) {
1305                         dev_dbg(&xd->dev,
1306                                 "link state change request not received yet, retrying\n");
1307                         return -EAGAIN;
1308                 }
1309                 dev_dbg(&xd->dev, "timeout waiting for link change request\n");
1310                 return -ETIMEDOUT;
1311         }
1312
1313         port = tb_port_at(xd->route, tb_xdomain_parent(xd));
1314
1315         /*
1316          * We can't use tb_xdomain_lane_bonding_enable() here because it
1317          * is the other side that initiates lane bonding. So here we
1318          * just set the width to both lane adapters and wait for the
1319          * link to transition bonded.
1320          */
1321         ret = tb_port_set_link_width(port->dual_link_port, width);
1322         if (ret) {
1323                 tb_port_warn(port->dual_link_port,
1324                              "failed to set link width to %d\n", width);
1325                 return ret;
1326         }
1327
1328         ret = tb_port_set_link_width(port, width);
1329         if (ret) {
1330                 tb_port_warn(port, "failed to set link width to %d\n", width);
1331                 return ret;
1332         }
1333
1334         ret = tb_port_wait_for_link_width(port, width, XDOMAIN_BONDING_TIMEOUT);
1335         if (ret) {
1336                 dev_warn(&xd->dev, "error waiting for link width to become %d\n",
1337                          width);
1338                 return ret;
1339         }
1340
1341         port->bonded = width == 2;
1342         port->dual_link_port->bonded = width == 2;
1343
1344         tb_port_update_credits(port);
1345         tb_xdomain_update_link_attributes(xd);
1346
1347         dev_dbg(&xd->dev, "lane bonding %sabled\n", width == 2 ? "en" : "dis");
1348         return 0;
1349 }
1350
1351 static int tb_xdomain_get_properties(struct tb_xdomain *xd)
1352 {
1353         struct tb_property_dir *dir;
1354         struct tb *tb = xd->tb;
1355         bool update = false;
1356         u32 *block = NULL;
1357         u32 gen = 0;
1358         int ret;
1359
1360         dev_dbg(&xd->dev, "requesting remote properties\n");
1361
1362         ret = tb_xdp_properties_request(tb->ctl, xd->route, xd->local_uuid,
1363                                         xd->remote_uuid, xd->state_retries,
1364                                         &block, &gen);
1365         if (ret < 0) {
1366                 if (xd->state_retries-- > 0) {
1367                         dev_dbg(&xd->dev,
1368                                 "failed to request remote properties, retrying\n");
1369                         return -EAGAIN;
1370                 } else {
1371                         /* Give up now */
1372                         dev_err(&xd->dev,
1373                                 "failed read XDomain properties from %pUb\n",
1374                                 xd->remote_uuid);
1375                 }
1376
1377                 return ret;
1378         }
1379
1380         mutex_lock(&xd->lock);
1381
1382         /* Only accept newer generation properties */
1383         if (xd->remote_properties && gen <= xd->remote_property_block_gen) {
1384                 ret = 0;
1385                 goto err_free_block;
1386         }
1387
1388         dir = tb_property_parse_dir(block, ret);
1389         if (!dir) {
1390                 dev_err(&xd->dev, "failed to parse XDomain properties\n");
1391                 ret = -ENOMEM;
1392                 goto err_free_block;
1393         }
1394
1395         ret = populate_properties(xd, dir);
1396         if (ret) {
1397                 dev_err(&xd->dev, "missing XDomain properties in response\n");
1398                 goto err_free_dir;
1399         }
1400
1401         /* Release the existing one */
1402         if (xd->remote_properties) {
1403                 tb_property_free_dir(xd->remote_properties);
1404                 update = true;
1405         }
1406
1407         xd->remote_properties = dir;
1408         xd->remote_property_block_gen = gen;
1409
1410         tb_xdomain_update_link_attributes(xd);
1411
1412         mutex_unlock(&xd->lock);
1413
1414         kfree(block);
1415
1416         /*
1417          * Now the device should be ready enough so we can add it to the
1418          * bus and let userspace know about it. If the device is already
1419          * registered, we notify the userspace that it has changed.
1420          */
1421         if (!update) {
1422                 struct tb_port *port;
1423
1424                 /* Now disable lane 1 if bonding was not enabled */
1425                 port = tb_port_at(xd->route, tb_xdomain_parent(xd));
1426                 if (!port->bonded)
1427                         tb_port_disable(port->dual_link_port);
1428
1429                 if (device_add(&xd->dev)) {
1430                         dev_err(&xd->dev, "failed to add XDomain device\n");
1431                         return -ENODEV;
1432                 }
1433                 dev_info(&xd->dev, "new host found, vendor=%#x device=%#x\n",
1434                          xd->vendor, xd->device);
1435                 if (xd->vendor_name && xd->device_name)
1436                         dev_info(&xd->dev, "%s %s\n", xd->vendor_name,
1437                                  xd->device_name);
1438
1439                 tb_xdomain_debugfs_init(xd);
1440         } else {
1441                 kobject_uevent(&xd->dev.kobj, KOBJ_CHANGE);
1442         }
1443
1444         enumerate_services(xd);
1445         return 0;
1446
1447 err_free_dir:
1448         tb_property_free_dir(dir);
1449 err_free_block:
1450         kfree(block);
1451         mutex_unlock(&xd->lock);
1452
1453         return ret;
1454 }
1455
1456 static void tb_xdomain_queue_uuid(struct tb_xdomain *xd)
1457 {
1458         xd->state = XDOMAIN_STATE_UUID;
1459         xd->state_retries = XDOMAIN_RETRIES;
1460         queue_delayed_work(xd->tb->wq, &xd->state_work,
1461                            msecs_to_jiffies(XDOMAIN_SHORT_TIMEOUT));
1462 }
1463
1464 static void tb_xdomain_queue_link_status(struct tb_xdomain *xd)
1465 {
1466         xd->state = XDOMAIN_STATE_LINK_STATUS;
1467         xd->state_retries = XDOMAIN_RETRIES;
1468         queue_delayed_work(xd->tb->wq, &xd->state_work,
1469                            msecs_to_jiffies(XDOMAIN_DEFAULT_TIMEOUT));
1470 }
1471
1472 static void tb_xdomain_queue_link_status2(struct tb_xdomain *xd)
1473 {
1474         xd->state = XDOMAIN_STATE_LINK_STATUS2;
1475         xd->state_retries = XDOMAIN_RETRIES;
1476         queue_delayed_work(xd->tb->wq, &xd->state_work,
1477                            msecs_to_jiffies(XDOMAIN_DEFAULT_TIMEOUT));
1478 }
1479
1480 static void tb_xdomain_queue_bonding(struct tb_xdomain *xd)
1481 {
1482         if (memcmp(xd->local_uuid, xd->remote_uuid, UUID_SIZE) > 0) {
1483                 dev_dbg(&xd->dev, "we have higher UUID, other side bonds the lanes\n");
1484                 xd->state = XDOMAIN_STATE_BONDING_UUID_HIGH;
1485         } else {
1486                 dev_dbg(&xd->dev, "we have lower UUID, bonding lanes\n");
1487                 xd->state = XDOMAIN_STATE_LINK_STATE_CHANGE;
1488         }
1489
1490         xd->state_retries = XDOMAIN_RETRIES;
1491         queue_delayed_work(xd->tb->wq, &xd->state_work,
1492                            msecs_to_jiffies(XDOMAIN_DEFAULT_TIMEOUT));
1493 }
1494
1495 static void tb_xdomain_queue_bonding_uuid_low(struct tb_xdomain *xd)
1496 {
1497         xd->state = XDOMAIN_STATE_BONDING_UUID_LOW;
1498         xd->state_retries = XDOMAIN_RETRIES;
1499         queue_delayed_work(xd->tb->wq, &xd->state_work,
1500                            msecs_to_jiffies(XDOMAIN_DEFAULT_TIMEOUT));
1501 }
1502
1503 static void tb_xdomain_queue_properties(struct tb_xdomain *xd)
1504 {
1505         xd->state = XDOMAIN_STATE_PROPERTIES;
1506         xd->state_retries = XDOMAIN_RETRIES;
1507         queue_delayed_work(xd->tb->wq, &xd->state_work,
1508                            msecs_to_jiffies(XDOMAIN_DEFAULT_TIMEOUT));
1509 }
1510
1511 static void tb_xdomain_queue_properties_changed(struct tb_xdomain *xd)
1512 {
1513         xd->properties_changed_retries = XDOMAIN_RETRIES;
1514         queue_delayed_work(xd->tb->wq, &xd->properties_changed_work,
1515                            msecs_to_jiffies(XDOMAIN_SHORT_TIMEOUT));
1516 }
1517
1518 static void tb_xdomain_state_work(struct work_struct *work)
1519 {
1520         struct tb_xdomain *xd = container_of(work, typeof(*xd), state_work.work);
1521         int ret, state = xd->state;
1522
1523         if (WARN_ON_ONCE(state < XDOMAIN_STATE_INIT ||
1524                          state > XDOMAIN_STATE_ERROR))
1525                 return;
1526
1527         dev_dbg(&xd->dev, "running state %s\n", state_names[state]);
1528
1529         switch (state) {
1530         case XDOMAIN_STATE_INIT:
1531                 if (xd->needs_uuid) {
1532                         tb_xdomain_queue_uuid(xd);
1533                 } else {
1534                         tb_xdomain_queue_properties_changed(xd);
1535                         tb_xdomain_queue_properties(xd);
1536                 }
1537                 break;
1538
1539         case XDOMAIN_STATE_UUID:
1540                 ret = tb_xdomain_get_uuid(xd);
1541                 if (ret) {
1542                         if (ret == -EAGAIN)
1543                                 goto retry_state;
1544                         xd->state = XDOMAIN_STATE_ERROR;
1545                 } else {
1546                         tb_xdomain_queue_properties_changed(xd);
1547                         if (xd->bonding_possible)
1548                                 tb_xdomain_queue_link_status(xd);
1549                         else
1550                                 tb_xdomain_queue_properties(xd);
1551                 }
1552                 break;
1553
1554         case XDOMAIN_STATE_LINK_STATUS:
1555                 ret = tb_xdomain_get_link_status(xd);
1556                 if (ret) {
1557                         if (ret == -EAGAIN)
1558                                 goto retry_state;
1559
1560                         /*
1561                          * If any of the lane bonding states fail we skip
1562                          * bonding completely and try to continue from
1563                          * reading properties.
1564                          */
1565                         tb_xdomain_queue_properties(xd);
1566                 } else {
1567                         tb_xdomain_queue_bonding(xd);
1568                 }
1569                 break;
1570
1571         case XDOMAIN_STATE_LINK_STATE_CHANGE:
1572                 ret = tb_xdomain_link_state_change(xd, 2);
1573                 if (ret) {
1574                         if (ret == -EAGAIN)
1575                                 goto retry_state;
1576                         tb_xdomain_queue_properties(xd);
1577                 } else {
1578                         tb_xdomain_queue_link_status2(xd);
1579                 }
1580                 break;
1581
1582         case XDOMAIN_STATE_LINK_STATUS2:
1583                 ret = tb_xdomain_get_link_status(xd);
1584                 if (ret) {
1585                         if (ret == -EAGAIN)
1586                                 goto retry_state;
1587                         tb_xdomain_queue_properties(xd);
1588                 } else {
1589                         tb_xdomain_queue_bonding_uuid_low(xd);
1590                 }
1591                 break;
1592
1593         case XDOMAIN_STATE_BONDING_UUID_LOW:
1594                 tb_xdomain_lane_bonding_enable(xd);
1595                 tb_xdomain_queue_properties(xd);
1596                 break;
1597
1598         case XDOMAIN_STATE_BONDING_UUID_HIGH:
1599                 if (tb_xdomain_bond_lanes_uuid_high(xd) == -EAGAIN)
1600                         goto retry_state;
1601                 tb_xdomain_queue_properties(xd);
1602                 break;
1603
1604         case XDOMAIN_STATE_PROPERTIES:
1605                 ret = tb_xdomain_get_properties(xd);
1606                 if (ret) {
1607                         if (ret == -EAGAIN)
1608                                 goto retry_state;
1609                         xd->state = XDOMAIN_STATE_ERROR;
1610                 } else {
1611                         xd->state = XDOMAIN_STATE_ENUMERATED;
1612                 }
1613                 break;
1614
1615         case XDOMAIN_STATE_ENUMERATED:
1616                 tb_xdomain_queue_properties(xd);
1617                 break;
1618
1619         case XDOMAIN_STATE_ERROR:
1620                 break;
1621
1622         default:
1623                 dev_warn(&xd->dev, "unexpected state %d\n", state);
1624                 break;
1625         }
1626
1627         return;
1628
1629 retry_state:
1630         queue_delayed_work(xd->tb->wq, &xd->state_work,
1631                            msecs_to_jiffies(XDOMAIN_DEFAULT_TIMEOUT));
1632 }
1633
1634 static void tb_xdomain_properties_changed(struct work_struct *work)
1635 {
1636         struct tb_xdomain *xd = container_of(work, typeof(*xd),
1637                                              properties_changed_work.work);
1638         int ret;
1639
1640         dev_dbg(&xd->dev, "sending properties changed notification\n");
1641
1642         ret = tb_xdp_properties_changed_request(xd->tb->ctl, xd->route,
1643                                 xd->properties_changed_retries, xd->local_uuid);
1644         if (ret) {
1645                 if (xd->properties_changed_retries-- > 0) {
1646                         dev_dbg(&xd->dev,
1647                                 "failed to send properties changed notification, retrying\n");
1648                         queue_delayed_work(xd->tb->wq,
1649                                            &xd->properties_changed_work,
1650                                            msecs_to_jiffies(XDOMAIN_DEFAULT_TIMEOUT));
1651                 }
1652                 dev_err(&xd->dev, "failed to send properties changed notification\n");
1653                 return;
1654         }
1655
1656         xd->properties_changed_retries = XDOMAIN_RETRIES;
1657 }
1658
1659 static ssize_t device_show(struct device *dev, struct device_attribute *attr,
1660                            char *buf)
1661 {
1662         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1663
1664         return sysfs_emit(buf, "%#x\n", xd->device);
1665 }
1666 static DEVICE_ATTR_RO(device);
1667
1668 static ssize_t
1669 device_name_show(struct device *dev, struct device_attribute *attr, char *buf)
1670 {
1671         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1672         int ret;
1673
1674         if (mutex_lock_interruptible(&xd->lock))
1675                 return -ERESTARTSYS;
1676         ret = sysfs_emit(buf, "%s\n", xd->device_name ?: "");
1677         mutex_unlock(&xd->lock);
1678
1679         return ret;
1680 }
1681 static DEVICE_ATTR_RO(device_name);
1682
1683 static ssize_t maxhopid_show(struct device *dev, struct device_attribute *attr,
1684                              char *buf)
1685 {
1686         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1687
1688         return sysfs_emit(buf, "%d\n", xd->remote_max_hopid);
1689 }
1690 static DEVICE_ATTR_RO(maxhopid);
1691
1692 static ssize_t vendor_show(struct device *dev, struct device_attribute *attr,
1693                            char *buf)
1694 {
1695         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1696
1697         return sysfs_emit(buf, "%#x\n", xd->vendor);
1698 }
1699 static DEVICE_ATTR_RO(vendor);
1700
1701 static ssize_t
1702 vendor_name_show(struct device *dev, struct device_attribute *attr, char *buf)
1703 {
1704         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1705         int ret;
1706
1707         if (mutex_lock_interruptible(&xd->lock))
1708                 return -ERESTARTSYS;
1709         ret = sysfs_emit(buf, "%s\n", xd->vendor_name ?: "");
1710         mutex_unlock(&xd->lock);
1711
1712         return ret;
1713 }
1714 static DEVICE_ATTR_RO(vendor_name);
1715
1716 static ssize_t unique_id_show(struct device *dev, struct device_attribute *attr,
1717                               char *buf)
1718 {
1719         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1720
1721         return sysfs_emit(buf, "%pUb\n", xd->remote_uuid);
1722 }
1723 static DEVICE_ATTR_RO(unique_id);
1724
1725 static ssize_t speed_show(struct device *dev, struct device_attribute *attr,
1726                           char *buf)
1727 {
1728         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1729
1730         return sysfs_emit(buf, "%u.0 Gb/s\n", xd->link_speed);
1731 }
1732
1733 static DEVICE_ATTR(rx_speed, 0444, speed_show, NULL);
1734 static DEVICE_ATTR(tx_speed, 0444, speed_show, NULL);
1735
1736 static ssize_t lanes_show(struct device *dev, struct device_attribute *attr,
1737                           char *buf)
1738 {
1739         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1740
1741         return sysfs_emit(buf, "%u\n", xd->link_width);
1742 }
1743
1744 static DEVICE_ATTR(rx_lanes, 0444, lanes_show, NULL);
1745 static DEVICE_ATTR(tx_lanes, 0444, lanes_show, NULL);
1746
1747 static struct attribute *xdomain_attrs[] = {
1748         &dev_attr_device.attr,
1749         &dev_attr_device_name.attr,
1750         &dev_attr_maxhopid.attr,
1751         &dev_attr_rx_lanes.attr,
1752         &dev_attr_rx_speed.attr,
1753         &dev_attr_tx_lanes.attr,
1754         &dev_attr_tx_speed.attr,
1755         &dev_attr_unique_id.attr,
1756         &dev_attr_vendor.attr,
1757         &dev_attr_vendor_name.attr,
1758         NULL,
1759 };
1760
1761 static const struct attribute_group xdomain_attr_group = {
1762         .attrs = xdomain_attrs,
1763 };
1764
1765 static const struct attribute_group *xdomain_attr_groups[] = {
1766         &xdomain_attr_group,
1767         NULL,
1768 };
1769
1770 static void tb_xdomain_release(struct device *dev)
1771 {
1772         struct tb_xdomain *xd = container_of(dev, struct tb_xdomain, dev);
1773
1774         put_device(xd->dev.parent);
1775
1776         kfree(xd->local_property_block);
1777         tb_property_free_dir(xd->remote_properties);
1778         ida_destroy(&xd->out_hopids);
1779         ida_destroy(&xd->in_hopids);
1780         ida_destroy(&xd->service_ids);
1781
1782         kfree(xd->local_uuid);
1783         kfree(xd->remote_uuid);
1784         kfree(xd->device_name);
1785         kfree(xd->vendor_name);
1786         kfree(xd);
1787 }
1788
1789 static void start_handshake(struct tb_xdomain *xd)
1790 {
1791         xd->state = XDOMAIN_STATE_INIT;
1792         queue_delayed_work(xd->tb->wq, &xd->state_work,
1793                            msecs_to_jiffies(XDOMAIN_SHORT_TIMEOUT));
1794 }
1795
1796 static void stop_handshake(struct tb_xdomain *xd)
1797 {
1798         cancel_delayed_work_sync(&xd->properties_changed_work);
1799         cancel_delayed_work_sync(&xd->state_work);
1800         xd->properties_changed_retries = 0;
1801         xd->state_retries = 0;
1802 }
1803
1804 static int __maybe_unused tb_xdomain_suspend(struct device *dev)
1805 {
1806         stop_handshake(tb_to_xdomain(dev));
1807         return 0;
1808 }
1809
1810 static int __maybe_unused tb_xdomain_resume(struct device *dev)
1811 {
1812         start_handshake(tb_to_xdomain(dev));
1813         return 0;
1814 }
1815
1816 static const struct dev_pm_ops tb_xdomain_pm_ops = {
1817         SET_SYSTEM_SLEEP_PM_OPS(tb_xdomain_suspend, tb_xdomain_resume)
1818 };
1819
1820 struct device_type tb_xdomain_type = {
1821         .name = "thunderbolt_xdomain",
1822         .release = tb_xdomain_release,
1823         .pm = &tb_xdomain_pm_ops,
1824 };
1825 EXPORT_SYMBOL_GPL(tb_xdomain_type);
1826
1827 /**
1828  * tb_xdomain_alloc() - Allocate new XDomain object
1829  * @tb: Domain where the XDomain belongs
1830  * @parent: Parent device (the switch through the connection to the
1831  *          other domain is reached).
1832  * @route: Route string used to reach the other domain
1833  * @local_uuid: Our local domain UUID
1834  * @remote_uuid: UUID of the other domain (optional)
1835  *
1836  * Allocates new XDomain structure and returns pointer to that. The
1837  * object must be released by calling tb_xdomain_put().
1838  */
1839 struct tb_xdomain *tb_xdomain_alloc(struct tb *tb, struct device *parent,
1840                                     u64 route, const uuid_t *local_uuid,
1841                                     const uuid_t *remote_uuid)
1842 {
1843         struct tb_switch *parent_sw = tb_to_switch(parent);
1844         struct tb_xdomain *xd;
1845         struct tb_port *down;
1846
1847         /* Make sure the downstream domain is accessible */
1848         down = tb_port_at(route, parent_sw);
1849         tb_port_unlock(down);
1850
1851         xd = kzalloc(sizeof(*xd), GFP_KERNEL);
1852         if (!xd)
1853                 return NULL;
1854
1855         xd->tb = tb;
1856         xd->route = route;
1857         xd->local_max_hopid = down->config.max_in_hop_id;
1858         ida_init(&xd->service_ids);
1859         ida_init(&xd->in_hopids);
1860         ida_init(&xd->out_hopids);
1861         mutex_init(&xd->lock);
1862         INIT_DELAYED_WORK(&xd->state_work, tb_xdomain_state_work);
1863         INIT_DELAYED_WORK(&xd->properties_changed_work,
1864                           tb_xdomain_properties_changed);
1865
1866         xd->local_uuid = kmemdup(local_uuid, sizeof(uuid_t), GFP_KERNEL);
1867         if (!xd->local_uuid)
1868                 goto err_free;
1869
1870         if (remote_uuid) {
1871                 xd->remote_uuid = kmemdup(remote_uuid, sizeof(uuid_t),
1872                                           GFP_KERNEL);
1873                 if (!xd->remote_uuid)
1874                         goto err_free_local_uuid;
1875         } else {
1876                 xd->needs_uuid = true;
1877                 xd->bonding_possible = !!down->dual_link_port;
1878         }
1879
1880         device_initialize(&xd->dev);
1881         xd->dev.parent = get_device(parent);
1882         xd->dev.bus = &tb_bus_type;
1883         xd->dev.type = &tb_xdomain_type;
1884         xd->dev.groups = xdomain_attr_groups;
1885         dev_set_name(&xd->dev, "%u-%llx", tb->index, route);
1886
1887         dev_dbg(&xd->dev, "local UUID %pUb\n", local_uuid);
1888         if (remote_uuid)
1889                 dev_dbg(&xd->dev, "remote UUID %pUb\n", remote_uuid);
1890
1891         /*
1892          * This keeps the DMA powered on as long as we have active
1893          * connection to another host.
1894          */
1895         pm_runtime_set_active(&xd->dev);
1896         pm_runtime_get_noresume(&xd->dev);
1897         pm_runtime_enable(&xd->dev);
1898
1899         return xd;
1900
1901 err_free_local_uuid:
1902         kfree(xd->local_uuid);
1903 err_free:
1904         kfree(xd);
1905
1906         return NULL;
1907 }
1908
1909 /**
1910  * tb_xdomain_add() - Add XDomain to the bus
1911  * @xd: XDomain to add
1912  *
1913  * This function starts XDomain discovery protocol handshake and
1914  * eventually adds the XDomain to the bus. After calling this function
1915  * the caller needs to call tb_xdomain_remove() in order to remove and
1916  * release the object regardless whether the handshake succeeded or not.
1917  */
1918 void tb_xdomain_add(struct tb_xdomain *xd)
1919 {
1920         /* Start exchanging properties with the other host */
1921         start_handshake(xd);
1922 }
1923
1924 static int unregister_service(struct device *dev, void *data)
1925 {
1926         device_unregister(dev);
1927         return 0;
1928 }
1929
1930 /**
1931  * tb_xdomain_remove() - Remove XDomain from the bus
1932  * @xd: XDomain to remove
1933  *
1934  * This will stop all ongoing configuration work and remove the XDomain
1935  * along with any services from the bus. When the last reference to @xd
1936  * is released the object will be released as well.
1937  */
1938 void tb_xdomain_remove(struct tb_xdomain *xd)
1939 {
1940         tb_xdomain_debugfs_remove(xd);
1941
1942         stop_handshake(xd);
1943
1944         device_for_each_child_reverse(&xd->dev, xd, unregister_service);
1945
1946         /*
1947          * Undo runtime PM here explicitly because it is possible that
1948          * the XDomain was never added to the bus and thus device_del()
1949          * is not called for it (device_del() would handle this otherwise).
1950          */
1951         pm_runtime_disable(&xd->dev);
1952         pm_runtime_put_noidle(&xd->dev);
1953         pm_runtime_set_suspended(&xd->dev);
1954
1955         if (!device_is_registered(&xd->dev)) {
1956                 put_device(&xd->dev);
1957         } else {
1958                 dev_info(&xd->dev, "host disconnected\n");
1959                 device_unregister(&xd->dev);
1960         }
1961 }
1962
1963 /**
1964  * tb_xdomain_lane_bonding_enable() - Enable lane bonding on XDomain
1965  * @xd: XDomain connection
1966  *
1967  * Lane bonding is disabled by default for XDomains. This function tries
1968  * to enable bonding by first enabling the port and waiting for the CL0
1969  * state.
1970  *
1971  * Return: %0 in case of success and negative errno in case of error.
1972  */
1973 int tb_xdomain_lane_bonding_enable(struct tb_xdomain *xd)
1974 {
1975         struct tb_port *port;
1976         int ret;
1977
1978         port = tb_port_at(xd->route, tb_xdomain_parent(xd));
1979         if (!port->dual_link_port)
1980                 return -ENODEV;
1981
1982         ret = tb_port_enable(port->dual_link_port);
1983         if (ret)
1984                 return ret;
1985
1986         ret = tb_wait_for_port(port->dual_link_port, true);
1987         if (ret < 0)
1988                 return ret;
1989         if (!ret)
1990                 return -ENOTCONN;
1991
1992         ret = tb_port_lane_bonding_enable(port);
1993         if (ret) {
1994                 tb_port_warn(port, "failed to enable lane bonding\n");
1995                 return ret;
1996         }
1997
1998         ret = tb_port_wait_for_link_width(port, 2, XDOMAIN_BONDING_TIMEOUT);
1999         if (ret) {
2000                 tb_port_warn(port, "failed to enable lane bonding\n");
2001                 return ret;
2002         }
2003
2004         tb_port_update_credits(port);
2005         tb_xdomain_update_link_attributes(xd);
2006
2007         dev_dbg(&xd->dev, "lane bonding enabled\n");
2008         return 0;
2009 }
2010 EXPORT_SYMBOL_GPL(tb_xdomain_lane_bonding_enable);
2011
2012 /**
2013  * tb_xdomain_lane_bonding_disable() - Disable lane bonding
2014  * @xd: XDomain connection
2015  *
2016  * Lane bonding is disabled by default for XDomains. If bonding has been
2017  * enabled, this function can be used to disable it.
2018  */
2019 void tb_xdomain_lane_bonding_disable(struct tb_xdomain *xd)
2020 {
2021         struct tb_port *port;
2022
2023         port = tb_port_at(xd->route, tb_xdomain_parent(xd));
2024         if (port->dual_link_port) {
2025                 tb_port_lane_bonding_disable(port);
2026                 if (tb_port_wait_for_link_width(port, 1, 100) == -ETIMEDOUT)
2027                         tb_port_warn(port, "timeout disabling lane bonding\n");
2028                 tb_port_disable(port->dual_link_port);
2029                 tb_port_update_credits(port);
2030                 tb_xdomain_update_link_attributes(xd);
2031
2032                 dev_dbg(&xd->dev, "lane bonding disabled\n");
2033         }
2034 }
2035 EXPORT_SYMBOL_GPL(tb_xdomain_lane_bonding_disable);
2036
2037 /**
2038  * tb_xdomain_alloc_in_hopid() - Allocate input HopID for tunneling
2039  * @xd: XDomain connection
2040  * @hopid: Preferred HopID or %-1 for next available
2041  *
2042  * Returns allocated HopID or negative errno. Specifically returns
2043  * %-ENOSPC if there are no more available HopIDs. Returned HopID is
2044  * guaranteed to be within range supported by the input lane adapter.
2045  * Call tb_xdomain_release_in_hopid() to release the allocated HopID.
2046  */
2047 int tb_xdomain_alloc_in_hopid(struct tb_xdomain *xd, int hopid)
2048 {
2049         if (hopid < 0)
2050                 hopid = TB_PATH_MIN_HOPID;
2051         if (hopid < TB_PATH_MIN_HOPID || hopid > xd->local_max_hopid)
2052                 return -EINVAL;
2053
2054         return ida_alloc_range(&xd->in_hopids, hopid, xd->local_max_hopid,
2055                                GFP_KERNEL);
2056 }
2057 EXPORT_SYMBOL_GPL(tb_xdomain_alloc_in_hopid);
2058
2059 /**
2060  * tb_xdomain_alloc_out_hopid() - Allocate output HopID for tunneling
2061  * @xd: XDomain connection
2062  * @hopid: Preferred HopID or %-1 for next available
2063  *
2064  * Returns allocated HopID or negative errno. Specifically returns
2065  * %-ENOSPC if there are no more available HopIDs. Returned HopID is
2066  * guaranteed to be within range supported by the output lane adapter.
2067  * Call tb_xdomain_release_in_hopid() to release the allocated HopID.
2068  */
2069 int tb_xdomain_alloc_out_hopid(struct tb_xdomain *xd, int hopid)
2070 {
2071         if (hopid < 0)
2072                 hopid = TB_PATH_MIN_HOPID;
2073         if (hopid < TB_PATH_MIN_HOPID || hopid > xd->remote_max_hopid)
2074                 return -EINVAL;
2075
2076         return ida_alloc_range(&xd->out_hopids, hopid, xd->remote_max_hopid,
2077                                GFP_KERNEL);
2078 }
2079 EXPORT_SYMBOL_GPL(tb_xdomain_alloc_out_hopid);
2080
2081 /**
2082  * tb_xdomain_release_in_hopid() - Release input HopID
2083  * @xd: XDomain connection
2084  * @hopid: HopID to release
2085  */
2086 void tb_xdomain_release_in_hopid(struct tb_xdomain *xd, int hopid)
2087 {
2088         ida_free(&xd->in_hopids, hopid);
2089 }
2090 EXPORT_SYMBOL_GPL(tb_xdomain_release_in_hopid);
2091
2092 /**
2093  * tb_xdomain_release_out_hopid() - Release output HopID
2094  * @xd: XDomain connection
2095  * @hopid: HopID to release
2096  */
2097 void tb_xdomain_release_out_hopid(struct tb_xdomain *xd, int hopid)
2098 {
2099         ida_free(&xd->out_hopids, hopid);
2100 }
2101 EXPORT_SYMBOL_GPL(tb_xdomain_release_out_hopid);
2102
2103 /**
2104  * tb_xdomain_enable_paths() - Enable DMA paths for XDomain connection
2105  * @xd: XDomain connection
2106  * @transmit_path: HopID we are using to send out packets
2107  * @transmit_ring: DMA ring used to send out packets
2108  * @receive_path: HopID the other end is using to send packets to us
2109  * @receive_ring: DMA ring used to receive packets from @receive_path
2110  *
2111  * The function enables DMA paths accordingly so that after successful
2112  * return the caller can send and receive packets using high-speed DMA
2113  * path. If a transmit or receive path is not needed, pass %-1 for those
2114  * parameters.
2115  *
2116  * Return: %0 in case of success and negative errno in case of error
2117  */
2118 int tb_xdomain_enable_paths(struct tb_xdomain *xd, int transmit_path,
2119                             int transmit_ring, int receive_path,
2120                             int receive_ring)
2121 {
2122         return tb_domain_approve_xdomain_paths(xd->tb, xd, transmit_path,
2123                                                transmit_ring, receive_path,
2124                                                receive_ring);
2125 }
2126 EXPORT_SYMBOL_GPL(tb_xdomain_enable_paths);
2127
2128 /**
2129  * tb_xdomain_disable_paths() - Disable DMA paths for XDomain connection
2130  * @xd: XDomain connection
2131  * @transmit_path: HopID we are using to send out packets
2132  * @transmit_ring: DMA ring used to send out packets
2133  * @receive_path: HopID the other end is using to send packets to us
2134  * @receive_ring: DMA ring used to receive packets from @receive_path
2135  *
2136  * This does the opposite of tb_xdomain_enable_paths(). After call to
2137  * this the caller is not expected to use the rings anymore. Passing %-1
2138  * as path/ring parameter means don't care. Normally the callers should
2139  * pass the same values here as they do when paths are enabled.
2140  *
2141  * Return: %0 in case of success and negative errno in case of error
2142  */
2143 int tb_xdomain_disable_paths(struct tb_xdomain *xd, int transmit_path,
2144                              int transmit_ring, int receive_path,
2145                              int receive_ring)
2146 {
2147         return tb_domain_disconnect_xdomain_paths(xd->tb, xd, transmit_path,
2148                                                   transmit_ring, receive_path,
2149                                                   receive_ring);
2150 }
2151 EXPORT_SYMBOL_GPL(tb_xdomain_disable_paths);
2152
2153 struct tb_xdomain_lookup {
2154         const uuid_t *uuid;
2155         u8 link;
2156         u8 depth;
2157         u64 route;
2158 };
2159
2160 static struct tb_xdomain *switch_find_xdomain(struct tb_switch *sw,
2161         const struct tb_xdomain_lookup *lookup)
2162 {
2163         struct tb_port *port;
2164
2165         tb_switch_for_each_port(sw, port) {
2166                 struct tb_xdomain *xd;
2167
2168                 if (port->xdomain) {
2169                         xd = port->xdomain;
2170
2171                         if (lookup->uuid) {
2172                                 if (xd->remote_uuid &&
2173                                     uuid_equal(xd->remote_uuid, lookup->uuid))
2174                                         return xd;
2175                         } else if (lookup->link &&
2176                                    lookup->link == xd->link &&
2177                                    lookup->depth == xd->depth) {
2178                                 return xd;
2179                         } else if (lookup->route &&
2180                                    lookup->route == xd->route) {
2181                                 return xd;
2182                         }
2183                 } else if (tb_port_has_remote(port)) {
2184                         xd = switch_find_xdomain(port->remote->sw, lookup);
2185                         if (xd)
2186                                 return xd;
2187                 }
2188         }
2189
2190         return NULL;
2191 }
2192
2193 /**
2194  * tb_xdomain_find_by_uuid() - Find an XDomain by UUID
2195  * @tb: Domain where the XDomain belongs to
2196  * @uuid: UUID to look for
2197  *
2198  * Finds XDomain by walking through the Thunderbolt topology below @tb.
2199  * The returned XDomain will have its reference count increased so the
2200  * caller needs to call tb_xdomain_put() when it is done with the
2201  * object.
2202  *
2203  * This will find all XDomains including the ones that are not yet added
2204  * to the bus (handshake is still in progress).
2205  *
2206  * The caller needs to hold @tb->lock.
2207  */
2208 struct tb_xdomain *tb_xdomain_find_by_uuid(struct tb *tb, const uuid_t *uuid)
2209 {
2210         struct tb_xdomain_lookup lookup;
2211         struct tb_xdomain *xd;
2212
2213         memset(&lookup, 0, sizeof(lookup));
2214         lookup.uuid = uuid;
2215
2216         xd = switch_find_xdomain(tb->root_switch, &lookup);
2217         return tb_xdomain_get(xd);
2218 }
2219 EXPORT_SYMBOL_GPL(tb_xdomain_find_by_uuid);
2220
2221 /**
2222  * tb_xdomain_find_by_link_depth() - Find an XDomain by link and depth
2223  * @tb: Domain where the XDomain belongs to
2224  * @link: Root switch link number
2225  * @depth: Depth in the link
2226  *
2227  * Finds XDomain by walking through the Thunderbolt topology below @tb.
2228  * The returned XDomain will have its reference count increased so the
2229  * caller needs to call tb_xdomain_put() when it is done with the
2230  * object.
2231  *
2232  * This will find all XDomains including the ones that are not yet added
2233  * to the bus (handshake is still in progress).
2234  *
2235  * The caller needs to hold @tb->lock.
2236  */
2237 struct tb_xdomain *tb_xdomain_find_by_link_depth(struct tb *tb, u8 link,
2238                                                  u8 depth)
2239 {
2240         struct tb_xdomain_lookup lookup;
2241         struct tb_xdomain *xd;
2242
2243         memset(&lookup, 0, sizeof(lookup));
2244         lookup.link = link;
2245         lookup.depth = depth;
2246
2247         xd = switch_find_xdomain(tb->root_switch, &lookup);
2248         return tb_xdomain_get(xd);
2249 }
2250
2251 /**
2252  * tb_xdomain_find_by_route() - Find an XDomain by route string
2253  * @tb: Domain where the XDomain belongs to
2254  * @route: XDomain route string
2255  *
2256  * Finds XDomain by walking through the Thunderbolt topology below @tb.
2257  * The returned XDomain will have its reference count increased so the
2258  * caller needs to call tb_xdomain_put() when it is done with the
2259  * object.
2260  *
2261  * This will find all XDomains including the ones that are not yet added
2262  * to the bus (handshake is still in progress).
2263  *
2264  * The caller needs to hold @tb->lock.
2265  */
2266 struct tb_xdomain *tb_xdomain_find_by_route(struct tb *tb, u64 route)
2267 {
2268         struct tb_xdomain_lookup lookup;
2269         struct tb_xdomain *xd;
2270
2271         memset(&lookup, 0, sizeof(lookup));
2272         lookup.route = route;
2273
2274         xd = switch_find_xdomain(tb->root_switch, &lookup);
2275         return tb_xdomain_get(xd);
2276 }
2277 EXPORT_SYMBOL_GPL(tb_xdomain_find_by_route);
2278
2279 bool tb_xdomain_handle_request(struct tb *tb, enum tb_cfg_pkg_type type,
2280                                const void *buf, size_t size)
2281 {
2282         const struct tb_protocol_handler *handler, *tmp;
2283         const struct tb_xdp_header *hdr = buf;
2284         unsigned int length;
2285         int ret = 0;
2286
2287         /* We expect the packet is at least size of the header */
2288         length = hdr->xd_hdr.length_sn & TB_XDOMAIN_LENGTH_MASK;
2289         if (length != size / 4 - sizeof(hdr->xd_hdr) / 4)
2290                 return true;
2291         if (length < sizeof(*hdr) / 4 - sizeof(hdr->xd_hdr) / 4)
2292                 return true;
2293
2294         /*
2295          * Handle XDomain discovery protocol packets directly here. For
2296          * other protocols (based on their UUID) we call registered
2297          * handlers in turn.
2298          */
2299         if (uuid_equal(&hdr->uuid, &tb_xdp_uuid)) {
2300                 if (type == TB_CFG_PKG_XDOMAIN_REQ)
2301                         return tb_xdp_schedule_request(tb, hdr, size);
2302                 return false;
2303         }
2304
2305         mutex_lock(&xdomain_lock);
2306         list_for_each_entry_safe(handler, tmp, &protocol_handlers, list) {
2307                 if (!uuid_equal(&hdr->uuid, handler->uuid))
2308                         continue;
2309
2310                 mutex_unlock(&xdomain_lock);
2311                 ret = handler->callback(buf, size, handler->data);
2312                 mutex_lock(&xdomain_lock);
2313
2314                 if (ret)
2315                         break;
2316         }
2317         mutex_unlock(&xdomain_lock);
2318
2319         return ret > 0;
2320 }
2321
2322 static int update_xdomain(struct device *dev, void *data)
2323 {
2324         struct tb_xdomain *xd;
2325
2326         xd = tb_to_xdomain(dev);
2327         if (xd) {
2328                 queue_delayed_work(xd->tb->wq, &xd->properties_changed_work,
2329                                    msecs_to_jiffies(50));
2330         }
2331
2332         return 0;
2333 }
2334
2335 static void update_all_xdomains(void)
2336 {
2337         bus_for_each_dev(&tb_bus_type, NULL, NULL, update_xdomain);
2338 }
2339
2340 static bool remove_directory(const char *key, const struct tb_property_dir *dir)
2341 {
2342         struct tb_property *p;
2343
2344         p = tb_property_find(xdomain_property_dir, key,
2345                              TB_PROPERTY_TYPE_DIRECTORY);
2346         if (p && p->value.dir == dir) {
2347                 tb_property_remove(p);
2348                 return true;
2349         }
2350         return false;
2351 }
2352
2353 /**
2354  * tb_register_property_dir() - Register property directory to the host
2355  * @key: Key (name) of the directory to add
2356  * @dir: Directory to add
2357  *
2358  * Service drivers can use this function to add new property directory
2359  * to the host available properties. The other connected hosts are
2360  * notified so they can re-read properties of this host if they are
2361  * interested.
2362  *
2363  * Return: %0 on success and negative errno on failure
2364  */
2365 int tb_register_property_dir(const char *key, struct tb_property_dir *dir)
2366 {
2367         int ret;
2368
2369         if (WARN_ON(!xdomain_property_dir))
2370                 return -EAGAIN;
2371
2372         if (!key || strlen(key) > 8)
2373                 return -EINVAL;
2374
2375         mutex_lock(&xdomain_lock);
2376         if (tb_property_find(xdomain_property_dir, key,
2377                              TB_PROPERTY_TYPE_DIRECTORY)) {
2378                 ret = -EEXIST;
2379                 goto err_unlock;
2380         }
2381
2382         ret = tb_property_add_dir(xdomain_property_dir, key, dir);
2383         if (ret)
2384                 goto err_unlock;
2385
2386         xdomain_property_block_gen++;
2387
2388         mutex_unlock(&xdomain_lock);
2389         update_all_xdomains();
2390         return 0;
2391
2392 err_unlock:
2393         mutex_unlock(&xdomain_lock);
2394         return ret;
2395 }
2396 EXPORT_SYMBOL_GPL(tb_register_property_dir);
2397
2398 /**
2399  * tb_unregister_property_dir() - Removes property directory from host
2400  * @key: Key (name) of the directory
2401  * @dir: Directory to remove
2402  *
2403  * This will remove the existing directory from this host and notify the
2404  * connected hosts about the change.
2405  */
2406 void tb_unregister_property_dir(const char *key, struct tb_property_dir *dir)
2407 {
2408         int ret = 0;
2409
2410         mutex_lock(&xdomain_lock);
2411         if (remove_directory(key, dir))
2412                 xdomain_property_block_gen++;
2413         mutex_unlock(&xdomain_lock);
2414
2415         if (!ret)
2416                 update_all_xdomains();
2417 }
2418 EXPORT_SYMBOL_GPL(tb_unregister_property_dir);
2419
2420 int tb_xdomain_init(void)
2421 {
2422         xdomain_property_dir = tb_property_create_dir(NULL);
2423         if (!xdomain_property_dir)
2424                 return -ENOMEM;
2425
2426         /*
2427          * Initialize standard set of properties without any service
2428          * directories. Those will be added by service drivers
2429          * themselves when they are loaded.
2430          *
2431          * Rest of the properties are filled dynamically based on these
2432          * when the P2P connection is made.
2433          */
2434         tb_property_add_immediate(xdomain_property_dir, "vendorid",
2435                                   PCI_VENDOR_ID_INTEL);
2436         tb_property_add_text(xdomain_property_dir, "vendorid", "Intel Corp.");
2437         tb_property_add_immediate(xdomain_property_dir, "deviceid", 0x1);
2438         tb_property_add_immediate(xdomain_property_dir, "devicerv", 0x80000100);
2439
2440         xdomain_property_block_gen = get_random_u32();
2441         return 0;
2442 }
2443
2444 void tb_xdomain_exit(void)
2445 {
2446         tb_property_free_dir(xdomain_property_dir);
2447 }