drivers/misc/mei/hbm.c

   1 /*
   2  *
   3  * Intel Management Engine Interface (Intel MEI) Linux driver
   4  * Copyright (c) 2003-2012, Intel Corporation.
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms and conditions of the GNU General Public License,
   8  * version 2, as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  *
  15  */
  16
  17 #include <linux/export.h>
  18 #include <linux/sched.h>
  19 #include <linux/wait.h>
  20 #include <linux/pm_runtime.h>
  21 #include <linux/slab.h>
  22
  23 #include <linux/mei.h>
  24
  25 #include "mei_dev.h"
  26 #include "hbm.h"
  27 #include "client.h"
  28
  29 static const char *mei_hbm_status_str(enum mei_hbm_status status)
  30 {
  31 #define MEI_HBM_STATUS(status) case MEI_HBMS_##status: return #status
  32         switch (status) {
  33         MEI_HBM_STATUS(SUCCESS);
  34         MEI_HBM_STATUS(CLIENT_NOT_FOUND);
  35         MEI_HBM_STATUS(ALREADY_EXISTS);
  36         MEI_HBM_STATUS(REJECTED);
  37         MEI_HBM_STATUS(INVALID_PARAMETER);
  38         MEI_HBM_STATUS(NOT_ALLOWED);
  39         MEI_HBM_STATUS(ALREADY_STARTED);
  40         MEI_HBM_STATUS(NOT_STARTED);
  41         default: return "unknown";
  42         }
  43 #undef MEI_HBM_STATUS
  44 };
  45
  46 static const char *mei_cl_conn_status_str(enum mei_cl_connect_status status)
  47 {
  48 #define MEI_CL_CS(status) case MEI_CL_CONN_##status: return #status
  49         switch (status) {
  50         MEI_CL_CS(SUCCESS);
  51         MEI_CL_CS(NOT_FOUND);
  52         MEI_CL_CS(ALREADY_STARTED);
  53         MEI_CL_CS(OUT_OF_RESOURCES);
  54         MEI_CL_CS(MESSAGE_SMALL);
  55         MEI_CL_CS(NOT_ALLOWED);
  56         default: return "unknown";
  57         }
  58 #undef MEI_CL_CCS
  59 }
  60
  61 const char *mei_hbm_state_str(enum mei_hbm_state state)
  62 {
  63 #define MEI_HBM_STATE(state) case MEI_HBM_##state: return #state
  64         switch (state) {
  65         MEI_HBM_STATE(IDLE);
  66         MEI_HBM_STATE(STARTING);
  67         MEI_HBM_STATE(STARTED);
  68         MEI_HBM_STATE(ENUM_CLIENTS);
  69         MEI_HBM_STATE(CLIENT_PROPERTIES);
  70         MEI_HBM_STATE(STOPPED);
  71         default:
  72                 return "unknown";
  73         }
  74 #undef MEI_HBM_STATE
  75 }
  76
  77 /**
  78  * mei_cl_conn_status_to_errno - convert client connect response
  79  * status to error code
  80  *
  81  * @status: client connect response status
  82  *
  83  * Return: corresponding error code
  84  */
  85 static int mei_cl_conn_status_to_errno(enum mei_cl_connect_status status)
  86 {
  87         switch (status) {
  88         case MEI_CL_CONN_SUCCESS:          return 0;
  89         case MEI_CL_CONN_NOT_FOUND:        return -ENOTTY;
  90         case MEI_CL_CONN_ALREADY_STARTED:  return -EBUSY;
  91         case MEI_CL_CONN_OUT_OF_RESOURCES: return -EBUSY;
  92         case MEI_CL_CONN_MESSAGE_SMALL:    return -EINVAL;
  93         case MEI_CL_CONN_NOT_ALLOWED:      return -EBUSY;
  94         default:                           return -EINVAL;
  95         }
  96 }
  97
  98 /**
  99  * mei_hbm_idle - set hbm to idle state
 100  *
 101  * @dev: the device structure
 102  */
 103 void mei_hbm_idle(struct mei_device *dev)
 104 {
 105         dev->init_clients_timer = 0;
 106         dev->hbm_state = MEI_HBM_IDLE;
 107 }
 108
 109 /**
 110  * mei_hbm_reset - reset hbm counters and book keeping data structurs
 111  *
 112  * @dev: the device structure
 113  */
 114 void mei_hbm_reset(struct mei_device *dev)
 115 {
 116         dev->me_client_index = 0;
 117
 118         mei_me_cl_rm_all(dev);
 119
 120         mei_hbm_idle(dev);
 121 }
 122
 123 /**
 124  * mei_hbm_hdr - construct hbm header
 125  *
 126  * @hdr: hbm header
 127  * @length: payload length
 128  */
 129
 130 static inline void mei_hbm_hdr(struct mei_msg_hdr *hdr, size_t length)
 131 {
 132         hdr->host_addr = 0;
 133         hdr->me_addr = 0;
 134         hdr->length = length;
 135         hdr->msg_complete = 1;
 136         hdr->reserved = 0;
 137 }
 138
 139 /**
 140  * mei_hbm_cl_hdr - construct client hbm header
 141  *
 142  * @cl: client
 143  * @hbm_cmd: host bus message command
 144  * @buf: buffer for cl header
 145  * @len: buffer length
 146  */
 147 static inline
 148 void mei_hbm_cl_hdr(struct mei_cl *cl, u8 hbm_cmd, void *buf, size_t len)
 149 {
 150         struct mei_hbm_cl_cmd *cmd = buf;
 151
 152         memset(cmd, 0, len);
 153
 154         cmd->hbm_cmd = hbm_cmd;
 155         cmd->host_addr = mei_cl_host_addr(cl);
 156         cmd->me_addr = mei_cl_me_id(cl);
 157 }
 158
 159 /**
 160  * mei_hbm_cl_write - write simple hbm client message
 161  *
 162  * @dev: the device structure
 163  * @cl: client
 164  * @hbm_cmd: host bus message command
 165  * @len: buffer length
 166  *
 167  * Return: 0 on success, <0 on failure.
 168  */
 169 static inline
 170 int mei_hbm_cl_write(struct mei_device *dev,
 171                      struct mei_cl *cl, u8 hbm_cmd, size_t len)
 172 {
 173         struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
 174
 175         mei_hbm_hdr(mei_hdr, len);
 176         mei_hbm_cl_hdr(cl, hbm_cmd, dev->wr_msg.data, len);
 177
 178         return mei_write_message(dev, mei_hdr, dev->wr_msg.data);
 179 }
 180
 181 /**
 182  * mei_hbm_cl_addr_equal - check if the client's and
 183  *      the message address match
 184  *
 185  * @cl: client
 186  * @cmd: hbm client message
 187  *
 188  * Return: true if addresses are the same
 189  */
 190 static inline
 191 bool mei_hbm_cl_addr_equal(struct mei_cl *cl, struct mei_hbm_cl_cmd *cmd)
 192 {
 193         return  mei_cl_host_addr(cl) == cmd->host_addr &&
 194                 mei_cl_me_id(cl) == cmd->me_addr;
 195 }
 196
 197 /**
 198  * mei_hbm_cl_find_by_cmd - find recipient client
 199  *
 200  * @dev: the device structure
 201  * @buf: a buffer with hbm cl command
 202  *
 203  * Return: the recipient client or NULL if not found
 204  */
 205 static inline
 206 struct mei_cl *mei_hbm_cl_find_by_cmd(struct mei_device *dev, void *buf)
 207 {
 208         struct mei_hbm_cl_cmd *cmd = (struct mei_hbm_cl_cmd *)buf;
 209         struct mei_cl *cl;
 210
 211         list_for_each_entry(cl, &dev->file_list, link)
 212                 if (mei_hbm_cl_addr_equal(cl, cmd))
 213                         return cl;
 214         return NULL;
 215 }
 216
 217
 218 /**
 219  * mei_hbm_start_wait - wait for start response message.
 220  *
 221  * @dev: the device structure
 222  *
 223  * Return: 0 on success and < 0 on failure
 224  */
 225 int mei_hbm_start_wait(struct mei_device *dev)
 226 {
 227         int ret;
 228
 229         if (dev->hbm_state > MEI_HBM_STARTING)
 230                 return 0;
 231
 232         mutex_unlock(&dev->device_lock);
 233         ret = wait_event_timeout(dev->wait_hbm_start,
 234                         dev->hbm_state != MEI_HBM_STARTING,
 235                         mei_secs_to_jiffies(MEI_HBM_TIMEOUT));
 236         mutex_lock(&dev->device_lock);
 237
 238         if (ret == 0 && (dev->hbm_state <= MEI_HBM_STARTING)) {
 239                 dev->hbm_state = MEI_HBM_IDLE;
 240                 dev_err(dev->dev, "waiting for mei start failed\n");
 241                 return -ETIME;
 242         }
 243         return 0;
 244 }
 245
 246 /**
 247  * mei_hbm_start_req - sends start request message.
 248  *
 249  * @dev: the device structure
 250  *
 251  * Return: 0 on success and < 0 on failure
 252  */
 253 int mei_hbm_start_req(struct mei_device *dev)
 254 {
 255         struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
 256         struct hbm_host_version_request *start_req;
 257         const size_t len = sizeof(struct hbm_host_version_request);
 258         int ret;
 259
 260         mei_hbm_reset(dev);
 261
 262         mei_hbm_hdr(mei_hdr, len);
 263
 264         /* host start message */
 265         start_req = (struct hbm_host_version_request *)dev->wr_msg.data;
 266         memset(start_req, 0, len);
 267         start_req->hbm_cmd = HOST_START_REQ_CMD;
 268         start_req->host_version.major_version = HBM_MAJOR_VERSION;
 269         start_req->host_version.minor_version = HBM_MINOR_VERSION;
 270
 271         dev->hbm_state = MEI_HBM_IDLE;
 272         ret = mei_write_message(dev, mei_hdr, dev->wr_msg.data);
 273         if (ret) {
 274                 dev_err(dev->dev, "version message write failed: ret = %d\n",
 275                         ret);
 276                 return ret;
 277         }
 278
 279         dev->hbm_state = MEI_HBM_STARTING;
 280         dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
 281         return 0;
 282 }
 283
 284 /**
 285  * mei_hbm_enum_clients_req - sends enumeration client request message.
 286  *
 287  * @dev: the device structure
 288  *
 289  * Return: 0 on success and < 0 on failure
 290  */
 291 static int mei_hbm_enum_clients_req(struct mei_device *dev)
 292 {
 293         struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
 294         struct hbm_host_enum_request *enum_req;
 295         const size_t len = sizeof(struct hbm_host_enum_request);
 296         int ret;
 297
 298         /* enumerate clients */
 299         mei_hbm_hdr(mei_hdr, len);
 300
 301         enum_req = (struct hbm_host_enum_request *)dev->wr_msg.data;
 302         memset(enum_req, 0, len);
 303         enum_req->hbm_cmd = HOST_ENUM_REQ_CMD;
 304         enum_req->flags |= dev->hbm_f_dc_supported ?
 305                            MEI_HBM_ENUM_F_ALLOW_ADD : 0;
 306         enum_req->flags |= dev->hbm_f_ie_supported ?
 307                            MEI_HBM_ENUM_F_IMMEDIATE_ENUM : 0;
 308
 309         ret = mei_write_message(dev, mei_hdr, dev->wr_msg.data);
 310         if (ret) {
 311                 dev_err(dev->dev, "enumeration request write failed: ret = %d.\n",
 312                         ret);
 313                 return ret;
 314         }
 315         dev->hbm_state = MEI_HBM_ENUM_CLIENTS;
 316         dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
 317         return 0;
 318 }
 319
 320 /**
 321  * mei_hbm_me_cl_add - add new me client to the list
 322  *
 323  * @dev: the device structure
 324  * @res: hbm property response
 325  *
 326  * Return: 0 on success and -ENOMEM on allocation failure
 327  */
 328
 329 static int mei_hbm_me_cl_add(struct mei_device *dev,
 330                              struct hbm_props_response *res)
 331 {
 332         struct mei_me_client *me_cl;
 333         const uuid_le *uuid = &res->client_properties.protocol_name;
 334
 335         mei_me_cl_rm_by_uuid(dev, uuid);
 336
 337         me_cl = kzalloc(sizeof(struct mei_me_client), GFP_KERNEL);
 338         if (!me_cl)
 339                 return -ENOMEM;
 340
 341         mei_me_cl_init(me_cl);
 342
 343         me_cl->props = res->client_properties;
 344         me_cl->client_id = res->me_addr;
 345         me_cl->mei_flow_ctrl_creds = 0;
 346
 347         mei_me_cl_add(dev, me_cl);
 348
 349         return 0;
 350 }
 351
 352 /**
 353  * mei_hbm_add_cl_resp - send response to fw on client add request
 354  *
 355  * @dev: the device structure
 356  * @addr: me address
 357  * @status: response status
 358  *
 359  * Return: 0 on success and < 0 on failure
 360  */
 361 static int mei_hbm_add_cl_resp(struct mei_device *dev, u8 addr, u8 status)
 362 {
 363         struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
 364         struct hbm_add_client_response *resp;
 365         const size_t len = sizeof(struct hbm_add_client_response);
 366         int ret;
 367
 368         dev_dbg(dev->dev, "adding client response\n");
 369
 370         resp = (struct hbm_add_client_response *)dev->wr_msg.data;
 371
 372         mei_hbm_hdr(mei_hdr, len);
 373         memset(resp, 0, sizeof(struct hbm_add_client_response));
 374
 375         resp->hbm_cmd = MEI_HBM_ADD_CLIENT_RES_CMD;
 376         resp->me_addr = addr;
 377         resp->status  = status;
 378
 379         ret = mei_write_message(dev, mei_hdr, dev->wr_msg.data);
 380         if (ret)
 381                 dev_err(dev->dev, "add client response write failed: ret = %d\n",
 382                         ret);
 383         return ret;
 384 }
 385
 386 /**
 387  * mei_hbm_fw_add_cl_req - request from the fw to add a client
 388  *
 389  * @dev: the device structure
 390  * @req: add client request
 391  *
 392  * Return: 0 on success and < 0 on failure
 393  */
 394 static int mei_hbm_fw_add_cl_req(struct mei_device *dev,
 395                               struct hbm_add_client_request *req)
 396 {
 397         int ret;
 398         u8 status = MEI_HBMS_SUCCESS;
 399
 400         BUILD_BUG_ON(sizeof(struct hbm_add_client_request) !=
 401                         sizeof(struct hbm_props_response));
 402
 403         ret = mei_hbm_me_cl_add(dev, (struct hbm_props_response *)req);
 404         if (ret)
 405                 status = !MEI_HBMS_SUCCESS;
 406
 407         if (dev->dev_state == MEI_DEV_ENABLED)
 408                 schedule_work(&dev->bus_rescan_work);
 409
 410         return mei_hbm_add_cl_resp(dev, req->me_addr, status);
 411 }
 412
 413 /**
 414  * mei_hbm_cl_notify_req - send notification request
 415  *
 416  * @dev: the device structure
 417  * @cl: a client to disconnect from
 418  * @start: true for start false for stop
 419  *
 420  * Return: 0 on success and -EIO on write failure
 421  */
 422 int mei_hbm_cl_notify_req(struct mei_device *dev,
 423                           struct mei_cl *cl, u8 start)
 424 {
 425
 426         struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
 427         struct hbm_notification_request *req;
 428         const size_t len = sizeof(struct hbm_notification_request);
 429         int ret;
 430
 431         mei_hbm_hdr(mei_hdr, len);
 432         mei_hbm_cl_hdr(cl, MEI_HBM_NOTIFY_REQ_CMD, dev->wr_msg.data, len);
 433
 434         req = (struct hbm_notification_request *)dev->wr_msg.data;
 435         req->start = start;
 436
 437         ret = mei_write_message(dev, mei_hdr, dev->wr_msg.data);
 438         if (ret)
 439                 dev_err(dev->dev, "notify request failed: ret = %d\n", ret);
 440
 441         return ret;
 442 }
 443
 444 /**
 445  *  notify_res_to_fop - convert notification response to the proper
 446  *      notification FOP
 447  *
 448  * @cmd: client notification start response command
 449  *
 450  * Return:  MEI_FOP_NOTIFY_START or MEI_FOP_NOTIFY_STOP;
 451  */
 452 static inline enum mei_cb_file_ops notify_res_to_fop(struct mei_hbm_cl_cmd *cmd)
 453 {
 454         struct hbm_notification_response *rs =
 455                 (struct hbm_notification_response *)cmd;
 456
 457         return mei_cl_notify_req2fop(rs->start);
 458 }
 459
 460 /**
 461  * mei_hbm_cl_notify_start_res - update the client state according
 462  *       notify start response
 463  *
 464  * @dev: the device structure
 465  * @cl: mei host client
 466  * @cmd: client notification start response command
 467  */
 468 static void mei_hbm_cl_notify_start_res(struct mei_device *dev,
 469                                         struct mei_cl *cl,
 470                                         struct mei_hbm_cl_cmd *cmd)
 471 {
 472         struct hbm_notification_response *rs =
 473                 (struct hbm_notification_response *)cmd;
 474
 475         cl_dbg(dev, cl, "hbm: notify start response status=%d\n", rs->status);
 476
 477         if (rs->status == MEI_HBMS_SUCCESS ||
 478             rs->status == MEI_HBMS_ALREADY_STARTED) {
 479                 cl->notify_en = true;
 480                 cl->status = 0;
 481         } else {
 482                 cl->status = -EINVAL;
 483         }
 484 }
 485
 486 /**
 487  * mei_hbm_cl_notify_stop_res - update the client state according
 488  *       notify stop response
 489  *
 490  * @dev: the device structure
 491  * @cl: mei host client
 492  * @cmd: client notification stop response command
 493  */
 494 static void mei_hbm_cl_notify_stop_res(struct mei_device *dev,
 495                                        struct mei_cl *cl,
 496                                        struct mei_hbm_cl_cmd *cmd)
 497 {
 498         struct hbm_notification_response *rs =
 499                 (struct hbm_notification_response *)cmd;
 500
 501         cl_dbg(dev, cl, "hbm: notify stop response status=%d\n", rs->status);
 502
 503         if (rs->status == MEI_HBMS_SUCCESS ||
 504             rs->status == MEI_HBMS_NOT_STARTED) {
 505                 cl->notify_en = false;
 506                 cl->status = 0;
 507         } else {
 508                 /* TODO: spec is not clear yet about other possible issues */
 509                 cl->status = -EINVAL;
 510         }
 511 }
 512
 513 /**
 514  * mei_hbm_cl_notify - signal notification event
 515  *
 516  * @dev: the device structure
 517  * @cmd: notification client message
 518  */
 519 static void mei_hbm_cl_notify(struct mei_device *dev,
 520                               struct mei_hbm_cl_cmd *cmd)
 521 {
 522         struct mei_cl *cl;
 523
 524         cl = mei_hbm_cl_find_by_cmd(dev, cmd);
 525         if (cl)
 526                 mei_cl_notify(cl);
 527 }
 528
 529 /**
 530  * mei_hbm_prop_req - request property for a single client
 531  *
 532  * @dev: the device structure
 533  *
 534  * Return: 0 on success and < 0 on failure
 535  */
 536
 537 static int mei_hbm_prop_req(struct mei_device *dev)
 538 {
 539
 540         struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
 541         struct hbm_props_request *prop_req;
 542         const size_t len = sizeof(struct hbm_props_request);
 543         unsigned long next_client_index;
 544         int ret;
 545
 546         next_client_index = find_next_bit(dev->me_clients_map, MEI_CLIENTS_MAX,
 547                                           dev->me_client_index);
 548
 549         /* We got all client properties */
 550         if (next_client_index == MEI_CLIENTS_MAX) {
 551                 dev->hbm_state = MEI_HBM_STARTED;
 552                 mei_host_client_init(dev);
 553
 554                 return 0;
 555         }
 556
 557         mei_hbm_hdr(mei_hdr, len);
 558         prop_req = (struct hbm_props_request *)dev->wr_msg.data;
 559
 560         memset(prop_req, 0, sizeof(struct hbm_props_request));
 561
 562         prop_req->hbm_cmd = HOST_CLIENT_PROPERTIES_REQ_CMD;
 563         prop_req->me_addr = next_client_index;
 564
 565         ret = mei_write_message(dev, mei_hdr, dev->wr_msg.data);
 566         if (ret) {
 567                 dev_err(dev->dev, "properties request write failed: ret = %d\n",
 568                         ret);
 569                 return ret;
 570         }
 571
 572         dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
 573         dev->me_client_index = next_client_index;
 574
 575         return 0;
 576 }
 577
 578 /**
 579  * mei_hbm_pg - sends pg command
 580  *
 581  * @dev: the device structure
 582  * @pg_cmd: the pg command code
 583  *
 584  * Return: -EIO on write failure
 585  *         -EOPNOTSUPP if the operation is not supported by the protocol
 586  */
 587 int mei_hbm_pg(struct mei_device *dev, u8 pg_cmd)
 588 {
 589         struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
 590         struct hbm_power_gate *req;
 591         const size_t len = sizeof(struct hbm_power_gate);
 592         int ret;
 593
 594         if (!dev->hbm_f_pg_supported)
 595                 return -EOPNOTSUPP;
 596
 597         mei_hbm_hdr(mei_hdr, len);
 598
 599         req = (struct hbm_power_gate *)dev->wr_msg.data;
 600         memset(req, 0, len);
 601         req->hbm_cmd = pg_cmd;
 602
 603         ret = mei_write_message(dev, mei_hdr, dev->wr_msg.data);
 604         if (ret)
 605                 dev_err(dev->dev, "power gate command write failed.\n");
 606         return ret;
 607 }
 608 EXPORT_SYMBOL_GPL(mei_hbm_pg);
 609
 610 /**
 611  * mei_hbm_stop_req - send stop request message
 612  *
 613  * @dev: mei device
 614  *
 615  * Return: -EIO on write failure
 616  */
 617 static int mei_hbm_stop_req(struct mei_device *dev)
 618 {
 619         struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
 620         struct hbm_host_stop_request *req =
 621                         (struct hbm_host_stop_request *)dev->wr_msg.data;
 622         const size_t len = sizeof(struct hbm_host_stop_request);
 623
 624         mei_hbm_hdr(mei_hdr, len);
 625
 626         memset(req, 0, len);
 627         req->hbm_cmd = HOST_STOP_REQ_CMD;
 628         req->reason = DRIVER_STOP_REQUEST;
 629
 630         return mei_write_message(dev, mei_hdr, dev->wr_msg.data);
 631 }
 632
 633 /**
 634  * mei_hbm_cl_flow_control_req - sends flow control request.
 635  *
 636  * @dev: the device structure
 637  * @cl: client info
 638  *
 639  * Return: -EIO on write failure
 640  */
 641 int mei_hbm_cl_flow_control_req(struct mei_device *dev, struct mei_cl *cl)
 642 {
 643         const size_t len = sizeof(struct hbm_flow_control);
 644
 645         cl_dbg(dev, cl, "sending flow control\n");
 646         return mei_hbm_cl_write(dev, cl, MEI_FLOW_CONTROL_CMD, len);
 647 }
 648
 649 /**
 650  * mei_hbm_add_single_flow_creds - adds single buffer credentials.
 651  *
 652  * @dev: the device structure
 653  * @flow: flow control.
 654  *
 655  * Return: 0 on success, < 0 otherwise
 656  */
 657 static int mei_hbm_add_single_flow_creds(struct mei_device *dev,
 658                                   struct hbm_flow_control *flow)
 659 {
 660         struct mei_me_client *me_cl;
 661         int rets;
 662
 663         me_cl = mei_me_cl_by_id(dev, flow->me_addr);
 664         if (!me_cl) {
 665                 dev_err(dev->dev, "no such me client %d\n",
 666                         flow->me_addr);
 667                 return -ENOENT;
 668         }
 669
 670         if (WARN_ON(me_cl->props.single_recv_buf == 0)) {
 671                 rets = -EINVAL;
 672                 goto out;
 673         }
 674
 675         me_cl->mei_flow_ctrl_creds++;
 676         dev_dbg(dev->dev, "recv flow ctrl msg ME %d (single) creds = %d.\n",
 677             flow->me_addr, me_cl->mei_flow_ctrl_creds);
 678
 679         rets = 0;
 680 out:
 681         mei_me_cl_put(me_cl);
 682         return rets;
 683 }
 684
 685 /**
 686  * mei_hbm_cl_flow_control_res - flow control response from me
 687  *
 688  * @dev: the device structure
 689  * @flow_control: flow control response bus message
 690  */
 691 static void mei_hbm_cl_flow_control_res(struct mei_device *dev,
 692                                         struct hbm_flow_control *flow_control)
 693 {
 694         struct mei_cl *cl;
 695
 696         if (!flow_control->host_addr) {
 697                 /* single receive buffer */
 698                 mei_hbm_add_single_flow_creds(dev, flow_control);
 699                 return;
 700         }
 701
 702         cl = mei_hbm_cl_find_by_cmd(dev, flow_control);
 703         if (cl) {
 704                 cl->mei_flow_ctrl_creds++;
 705                 cl_dbg(dev, cl, "flow control creds = %d.\n",
 706                                 cl->mei_flow_ctrl_creds);
 707         }
 708 }
 709
 710
 711 /**
 712  * mei_hbm_cl_disconnect_req - sends disconnect message to fw.
 713  *
 714  * @dev: the device structure
 715  * @cl: a client to disconnect from
 716  *
 717  * Return: -EIO on write failure
 718  */
 719 int mei_hbm_cl_disconnect_req(struct mei_device *dev, struct mei_cl *cl)
 720 {
 721         const size_t len = sizeof(struct hbm_client_connect_request);
 722
 723         return mei_hbm_cl_write(dev, cl, CLIENT_DISCONNECT_REQ_CMD, len);
 724 }
 725
 726 /**
 727  * mei_hbm_cl_disconnect_rsp - sends disconnect respose to the FW
 728  *
 729  * @dev: the device structure
 730  * @cl: a client to disconnect from
 731  *
 732  * Return: -EIO on write failure
 733  */
 734 int mei_hbm_cl_disconnect_rsp(struct mei_device *dev, struct mei_cl *cl)
 735 {
 736         const size_t len = sizeof(struct hbm_client_connect_response);
 737
 738         return mei_hbm_cl_write(dev, cl, CLIENT_DISCONNECT_RES_CMD, len);
 739 }
 740
 741 /**
 742  * mei_hbm_cl_disconnect_res - update the client state according
 743  *       disconnect response
 744  *
 745  * @dev: the device structure
 746  * @cl: mei host client
 747  * @cmd: disconnect client response host bus message
 748  */
 749 static void mei_hbm_cl_disconnect_res(struct mei_device *dev, struct mei_cl *cl,
 750                                       struct mei_hbm_cl_cmd *cmd)
 751 {
 752         struct hbm_client_connect_response *rs =
 753                 (struct hbm_client_connect_response *)cmd;
 754
 755         cl_dbg(dev, cl, "hbm: disconnect response status=%d\n", rs->status);
 756
 757         if (rs->status == MEI_CL_DISCONN_SUCCESS)
 758                 cl->state = MEI_FILE_DISCONNECT_REPLY;
 759         cl->status = 0;
 760 }
 761
 762 /**
 763  * mei_hbm_cl_connect_req - send connection request to specific me client
 764  *
 765  * @dev: the device structure
 766  * @cl: a client to connect to
 767  *
 768  * Return: -EIO on write failure
 769  */
 770 int mei_hbm_cl_connect_req(struct mei_device *dev, struct mei_cl *cl)
 771 {
 772         const size_t len = sizeof(struct hbm_client_connect_request);
 773
 774         return mei_hbm_cl_write(dev, cl, CLIENT_CONNECT_REQ_CMD, len);
 775 }
 776
 777 /**
 778  * mei_hbm_cl_connect_res - update the client state according
 779  *        connection response
 780  *
 781  * @dev: the device structure
 782  * @cl: mei host client
 783  * @cmd: connect client response host bus message
 784  */
 785 static void mei_hbm_cl_connect_res(struct mei_device *dev, struct mei_cl *cl,
 786                                    struct mei_hbm_cl_cmd *cmd)
 787 {
 788         struct hbm_client_connect_response *rs =
 789                 (struct hbm_client_connect_response *)cmd;
 790
 791         cl_dbg(dev, cl, "hbm: connect response status=%s\n",
 792                         mei_cl_conn_status_str(rs->status));
 793
 794         if (rs->status == MEI_CL_CONN_SUCCESS)
 795                 cl->state = MEI_FILE_CONNECTED;
 796         else {
 797                 cl->state = MEI_FILE_DISCONNECT_REPLY;
 798                 if (rs->status == MEI_CL_CONN_NOT_FOUND) {
 799                         mei_me_cl_del(dev, cl->me_cl);
 800                         if (dev->dev_state == MEI_DEV_ENABLED)
 801                                 schedule_work(&dev->bus_rescan_work);
 802                 }
 803         }
 804         cl->status = mei_cl_conn_status_to_errno(rs->status);
 805 }
 806
 807 /**
 808  * mei_hbm_cl_res - process hbm response received on behalf
 809  *         an client
 810  *
 811  * @dev: the device structure
 812  * @rs:  hbm client message
 813  * @fop_type: file operation type
 814  */
 815 static void mei_hbm_cl_res(struct mei_device *dev,
 816                            struct mei_hbm_cl_cmd *rs,
 817                            enum mei_cb_file_ops fop_type)
 818 {
 819         struct mei_cl *cl;
 820         struct mei_cl_cb *cb, *next;
 821
 822         cl = NULL;
 823         list_for_each_entry_safe(cb, next, &dev->ctrl_rd_list.list, list) {
 824
 825                 cl = cb->cl;
 826
 827                 if (cb->fop_type != fop_type)
 828                         continue;
 829
 830                 if (mei_hbm_cl_addr_equal(cl, rs)) {
 831                         list_del_init(&cb->list);
 832                         break;
 833                 }
 834         }
 835
 836         if (!cl)
 837                 return;
 838
 839         switch (fop_type) {
 840         case MEI_FOP_CONNECT:
 841                 mei_hbm_cl_connect_res(dev, cl, rs);
 842                 break;
 843         case MEI_FOP_DISCONNECT:
 844                 mei_hbm_cl_disconnect_res(dev, cl, rs);
 845                 break;
 846         case MEI_FOP_NOTIFY_START:
 847                 mei_hbm_cl_notify_start_res(dev, cl, rs);
 848                 break;
 849         case MEI_FOP_NOTIFY_STOP:
 850                 mei_hbm_cl_notify_stop_res(dev, cl, rs);
 851                 break;
 852         default:
 853                 return;
 854         }
 855
 856         cl->timer_count = 0;
 857         wake_up(&cl->wait);
 858 }
 859
 860
 861 /**
 862  * mei_hbm_fw_disconnect_req - disconnect request initiated by ME firmware
 863  *  host sends disconnect response
 864  *
 865  * @dev: the device structure.
 866  * @disconnect_req: disconnect request bus message from the me
 867  *
 868  * Return: -ENOMEM on allocation failure
 869  */
 870 static int mei_hbm_fw_disconnect_req(struct mei_device *dev,
 871                 struct hbm_client_connect_request *disconnect_req)
 872 {
 873         struct mei_cl *cl;
 874         struct mei_cl_cb *cb;
 875
 876         cl = mei_hbm_cl_find_by_cmd(dev, disconnect_req);
 877         if (cl) {
 878                 cl_warn(dev, cl, "fw disconnect request received\n");
 879                 cl->state = MEI_FILE_DISCONNECTING;
 880                 cl->timer_count = 0;
 881
 882                 cb = mei_io_cb_init(cl, MEI_FOP_DISCONNECT_RSP, NULL);
 883                 if (!cb)
 884                         return -ENOMEM;
 885                 cl_dbg(dev, cl, "add disconnect response as first\n");
 886                 list_add(&cb->list, &dev->ctrl_wr_list.list);
 887         }
 888         return 0;
 889 }
 890
 891 /**
 892  * mei_hbm_pg_enter_res - PG enter response received
 893  *
 894  * @dev: the device structure.
 895  *
 896  * Return: 0 on success, -EPROTO on state mismatch
 897  */
 898 static int mei_hbm_pg_enter_res(struct mei_device *dev)
 899 {
 900         if (mei_pg_state(dev) != MEI_PG_OFF ||
 901             dev->pg_event != MEI_PG_EVENT_WAIT) {
 902                 dev_err(dev->dev, "hbm: pg entry response: state mismatch [%s, %d]\n",
 903                         mei_pg_state_str(mei_pg_state(dev)), dev->pg_event);
 904                 return -EPROTO;
 905         }
 906
 907         dev->pg_event = MEI_PG_EVENT_RECEIVED;
 908         wake_up(&dev->wait_pg);
 909
 910         return 0;
 911 }
 912
 913 /**
 914  * mei_hbm_pg_resume - process with PG resume
 915  *
 916  * @dev: the device structure.
 917  */
 918 void mei_hbm_pg_resume(struct mei_device *dev)
 919 {
 920         pm_request_resume(dev->dev);
 921 }
 922 EXPORT_SYMBOL_GPL(mei_hbm_pg_resume);
 923
 924 /**
 925  * mei_hbm_pg_exit_res - PG exit response received
 926  *
 927  * @dev: the device structure.
 928  *
 929  * Return: 0 on success, -EPROTO on state mismatch
 930  */
 931 static int mei_hbm_pg_exit_res(struct mei_device *dev)
 932 {
 933         if (mei_pg_state(dev) != MEI_PG_ON ||
 934             (dev->pg_event != MEI_PG_EVENT_WAIT &&
 935              dev->pg_event != MEI_PG_EVENT_IDLE)) {
 936                 dev_err(dev->dev, "hbm: pg exit response: state mismatch [%s, %d]\n",
 937                         mei_pg_state_str(mei_pg_state(dev)), dev->pg_event);
 938                 return -EPROTO;
 939         }
 940
 941         switch (dev->pg_event) {
 942         case MEI_PG_EVENT_WAIT:
 943                 dev->pg_event = MEI_PG_EVENT_RECEIVED;
 944                 wake_up(&dev->wait_pg);
 945                 break;
 946         case MEI_PG_EVENT_IDLE:
 947                 /*
 948                 * If the driver is not waiting on this then
 949                 * this is HW initiated exit from PG.
 950                 * Start runtime pm resume sequence to exit from PG.
 951                 */
 952                 dev->pg_event = MEI_PG_EVENT_RECEIVED;
 953                 mei_hbm_pg_resume(dev);
 954                 break;
 955         default:
 956                 WARN(1, "hbm: pg exit response: unexpected pg event = %d\n",
 957                      dev->pg_event);
 958                 return -EPROTO;
 959         }
 960
 961         return 0;
 962 }
 963
 964 /**
 965  * mei_hbm_config_features - check what hbm features and commands
 966  *        are supported by the fw
 967  *
 968  * @dev: the device structure
 969  */
 970 static void mei_hbm_config_features(struct mei_device *dev)
 971 {
 972         /* Power Gating Isolation Support */
 973         dev->hbm_f_pg_supported = 0;
 974         if (dev->version.major_version > HBM_MAJOR_VERSION_PGI)
 975                 dev->hbm_f_pg_supported = 1;
 976
 977         if (dev->version.major_version == HBM_MAJOR_VERSION_PGI &&
 978             dev->version.minor_version >= HBM_MINOR_VERSION_PGI)
 979                 dev->hbm_f_pg_supported = 1;
 980
 981         if (dev->version.major_version >= HBM_MAJOR_VERSION_DC)
 982                 dev->hbm_f_dc_supported = 1;
 983
 984         if (dev->version.major_version >= HBM_MAJOR_VERSION_IE)
 985                 dev->hbm_f_ie_supported = 1;
 986
 987         /* disconnect on connect timeout instead of link reset */
 988         if (dev->version.major_version >= HBM_MAJOR_VERSION_DOT)
 989                 dev->hbm_f_dot_supported = 1;
 990
 991         /* Notification Event Support */
 992         if (dev->version.major_version >= HBM_MAJOR_VERSION_EV)
 993                 dev->hbm_f_ev_supported = 1;
 994
 995         /* Fixed Address Client Support */
 996         if (dev->version.major_version >= HBM_MAJOR_VERSION_FA)
 997                 dev->hbm_f_fa_supported = 1;
 998 }
 999
1000 /**
1001  * mei_hbm_version_is_supported - checks whether the driver can
1002  *     support the hbm version of the device
1003  *
1004  * @dev: the device structure
1005  * Return: true if driver can support hbm version of the device
1006  */
1007 bool mei_hbm_version_is_supported(struct mei_device *dev)
1008 {
1009         return  (dev->version.major_version < HBM_MAJOR_VERSION) ||
1010                 (dev->version.major_version == HBM_MAJOR_VERSION &&
1011                  dev->version.minor_version <= HBM_MINOR_VERSION);
1012 }
1013
1014 /**
1015  * mei_hbm_dispatch - bottom half read routine after ISR to
1016  * handle the read bus message cmd processing.
1017  *
1018  * @dev: the device structure
1019  * @hdr: header of bus message
1020  *
1021  * Return: 0 on success and < 0 on failure
1022  */
1023 int mei_hbm_dispatch(struct mei_device *dev, struct mei_msg_hdr *hdr)
1024 {
1025         struct mei_bus_message *mei_msg;
1026         struct hbm_host_version_response *version_res;
1027         struct hbm_props_response *props_res;
1028         struct hbm_host_enum_response *enum_res;
1029         struct hbm_add_client_request *add_cl_req;
1030         int ret;
1031
1032         struct mei_hbm_cl_cmd *cl_cmd;
1033         struct hbm_client_connect_request *disconnect_req;
1034         struct hbm_flow_control *flow_control;
1035
1036         /* read the message to our buffer */
1037         BUG_ON(hdr->length >= sizeof(dev->rd_msg_buf));
1038         mei_read_slots(dev, dev->rd_msg_buf, hdr->length);
1039         mei_msg = (struct mei_bus_message *)dev->rd_msg_buf;
1040         cl_cmd  = (struct mei_hbm_cl_cmd *)mei_msg;
1041
1042         /* ignore spurious message and prevent reset nesting
1043          * hbm is put to idle during system reset
1044          */
1045         if (dev->hbm_state == MEI_HBM_IDLE) {
1046                 dev_dbg(dev->dev, "hbm: state is idle ignore spurious messages\n");
1047                 return 0;
1048         }
1049
1050         switch (mei_msg->hbm_cmd) {
1051         case HOST_START_RES_CMD:
1052                 dev_dbg(dev->dev, "hbm: start: response message received.\n");
1053
1054                 dev->init_clients_timer = 0;
1055
1056                 version_res = (struct hbm_host_version_response *)mei_msg;
1057
1058                 dev_dbg(dev->dev, "HBM VERSION: DRIVER=%02d:%02d DEVICE=%02d:%02d\n",
1059                                 HBM_MAJOR_VERSION, HBM_MINOR_VERSION,
1060                                 version_res->me_max_version.major_version,
1061                                 version_res->me_max_version.minor_version);
1062
1063                 if (version_res->host_version_supported) {
1064                         dev->version.major_version = HBM_MAJOR_VERSION;
1065                         dev->version.minor_version = HBM_MINOR_VERSION;
1066                 } else {
1067                         dev->version.major_version =
1068                                 version_res->me_max_version.major_version;
1069                         dev->version.minor_version =
1070                                 version_res->me_max_version.minor_version;
1071                 }
1072
1073                 if (!mei_hbm_version_is_supported(dev)) {
1074                         dev_warn(dev->dev, "hbm: start: version mismatch - stopping the driver.\n");
1075
1076                         dev->hbm_state = MEI_HBM_STOPPED;
1077                         if (mei_hbm_stop_req(dev)) {
1078                                 dev_err(dev->dev, "hbm: start: failed to send stop request\n");
1079                                 return -EIO;
1080                         }
1081                         break;
1082                 }
1083
1084                 mei_hbm_config_features(dev);
1085
1086                 if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
1087                     dev->hbm_state != MEI_HBM_STARTING) {
1088                         dev_err(dev->dev, "hbm: start: state mismatch, [%d, %d]\n",
1089                                 dev->dev_state, dev->hbm_state);
1090                         return -EPROTO;
1091                 }
1092
1093                 if (mei_hbm_enum_clients_req(dev)) {
1094                         dev_err(dev->dev, "hbm: start: failed to send enumeration request\n");
1095                         return -EIO;
1096                 }
1097
1098                 wake_up(&dev->wait_hbm_start);
1099                 break;
1100
1101         case CLIENT_CONNECT_RES_CMD:
1102                 dev_dbg(dev->dev, "hbm: client connect response: message received.\n");
1103                 mei_hbm_cl_res(dev, cl_cmd, MEI_FOP_CONNECT);
1104                 break;
1105
1106         case CLIENT_DISCONNECT_RES_CMD:
1107                 dev_dbg(dev->dev, "hbm: client disconnect response: message received.\n");
1108                 mei_hbm_cl_res(dev, cl_cmd, MEI_FOP_DISCONNECT);
1109                 break;
1110
1111         case MEI_FLOW_CONTROL_CMD:
1112                 dev_dbg(dev->dev, "hbm: client flow control response: message received.\n");
1113
1114                 flow_control = (struct hbm_flow_control *) mei_msg;
1115                 mei_hbm_cl_flow_control_res(dev, flow_control);
1116                 break;
1117
1118         case MEI_PG_ISOLATION_ENTRY_RES_CMD:
1119                 dev_dbg(dev->dev, "hbm: power gate isolation entry response received\n");
1120                 ret = mei_hbm_pg_enter_res(dev);
1121                 if (ret)
1122                         return ret;
1123                 break;
1124
1125         case MEI_PG_ISOLATION_EXIT_REQ_CMD:
1126                 dev_dbg(dev->dev, "hbm: power gate isolation exit request received\n");
1127                 ret = mei_hbm_pg_exit_res(dev);
1128                 if (ret)
1129                         return ret;
1130                 break;
1131
1132         case HOST_CLIENT_PROPERTIES_RES_CMD:
1133                 dev_dbg(dev->dev, "hbm: properties response: message received.\n");
1134
1135                 dev->init_clients_timer = 0;
1136
1137                 if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
1138                     dev->hbm_state != MEI_HBM_CLIENT_PROPERTIES) {
1139                         dev_err(dev->dev, "hbm: properties response: state mismatch, [%d, %d]\n",
1140                                 dev->dev_state, dev->hbm_state);
1141                         return -EPROTO;
1142                 }
1143
1144                 props_res = (struct hbm_props_response *)mei_msg;
1145
1146                 if (props_res->status) {
1147                         dev_err(dev->dev, "hbm: properties response: wrong status = %d %s\n",
1148                                 props_res->status,
1149                                 mei_hbm_status_str(props_res->status));
1150                         return -EPROTO;
1151                 }
1152
1153                 mei_hbm_me_cl_add(dev, props_res);
1154
1155                 dev->me_client_index++;
1156
1157                 /* request property for the next client */
1158                 if (mei_hbm_prop_req(dev))
1159                         return -EIO;
1160
1161                 break;
1162
1163         case HOST_ENUM_RES_CMD:
1164                 dev_dbg(dev->dev, "hbm: enumeration response: message received\n");
1165
1166                 dev->init_clients_timer = 0;
1167
1168                 enum_res = (struct hbm_host_enum_response *) mei_msg;
1169                 BUILD_BUG_ON(sizeof(dev->me_clients_map)
1170                                 < sizeof(enum_res->valid_addresses));
1171                 memcpy(dev->me_clients_map, enum_res->valid_addresses,
1172                                 sizeof(enum_res->valid_addresses));
1173
1174                 if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
1175                     dev->hbm_state != MEI_HBM_ENUM_CLIENTS) {
1176                         dev_err(dev->dev, "hbm: enumeration response: state mismatch, [%d, %d]\n",
1177                                 dev->dev_state, dev->hbm_state);
1178                         return -EPROTO;
1179                 }
1180
1181                 dev->hbm_state = MEI_HBM_CLIENT_PROPERTIES;
1182
1183                 /* first property request */
1184                 if (mei_hbm_prop_req(dev))
1185                         return -EIO;
1186
1187                 break;
1188
1189         case HOST_STOP_RES_CMD:
1190                 dev_dbg(dev->dev, "hbm: stop response: message received\n");
1191
1192                 dev->init_clients_timer = 0;
1193
1194                 if (dev->hbm_state != MEI_HBM_STOPPED) {
1195                         dev_err(dev->dev, "hbm: stop response: state mismatch, [%d, %d]\n",
1196                                 dev->dev_state, dev->hbm_state);
1197                         return -EPROTO;
1198                 }
1199
1200                 dev->dev_state = MEI_DEV_POWER_DOWN;
1201                 dev_info(dev->dev, "hbm: stop response: resetting.\n");
1202                 /* force the reset */
1203                 return -EPROTO;
1204                 break;
1205
1206         case CLIENT_DISCONNECT_REQ_CMD:
1207                 dev_dbg(dev->dev, "hbm: disconnect request: message received\n");
1208
1209                 disconnect_req = (struct hbm_client_connect_request *)mei_msg;
1210                 mei_hbm_fw_disconnect_req(dev, disconnect_req);
1211                 break;
1212
1213         case ME_STOP_REQ_CMD:
1214                 dev_dbg(dev->dev, "hbm: stop request: message received\n");
1215                 dev->hbm_state = MEI_HBM_STOPPED;
1216                 if (mei_hbm_stop_req(dev)) {
1217                         dev_err(dev->dev, "hbm: stop request: failed to send stop request\n");
1218                         return -EIO;
1219                 }
1220                 break;
1221
1222         case MEI_HBM_ADD_CLIENT_REQ_CMD:
1223                 dev_dbg(dev->dev, "hbm: add client request received\n");
1224                 /*
1225                  * after the host receives the enum_resp
1226                  * message clients may be added or removed
1227                  */
1228                 if (dev->hbm_state <= MEI_HBM_ENUM_CLIENTS ||
1229                     dev->hbm_state >= MEI_HBM_STOPPED) {
1230                         dev_err(dev->dev, "hbm: add client: state mismatch, [%d, %d]\n",
1231                                 dev->dev_state, dev->hbm_state);
1232                         return -EPROTO;
1233                 }
1234                 add_cl_req = (struct hbm_add_client_request *)mei_msg;
1235                 ret = mei_hbm_fw_add_cl_req(dev, add_cl_req);
1236                 if (ret) {
1237                         dev_err(dev->dev, "hbm: add client: failed to send response %d\n",
1238                                 ret);
1239                         return -EIO;
1240                 }
1241                 dev_dbg(dev->dev, "hbm: add client request processed\n");
1242                 break;
1243
1244         case MEI_HBM_NOTIFY_RES_CMD:
1245                 dev_dbg(dev->dev, "hbm: notify response received\n");
1246                 mei_hbm_cl_res(dev, cl_cmd, notify_res_to_fop(cl_cmd));
1247                 break;
1248
1249         case MEI_HBM_NOTIFICATION_CMD:
1250                 dev_dbg(dev->dev, "hbm: notification\n");
1251                 mei_hbm_cl_notify(dev, cl_cmd);
1252                 break;
1253
1254         default:
1255                 BUG();
1256                 break;
1257
1258         }
1259         return 0;
1260 }
1261