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         default: return "unknown";
  56         }
  57 #undef MEI_CL_CCS
  58 }
  59
  60 const char *mei_hbm_state_str(enum mei_hbm_state state)
  61 {
  62 #define MEI_HBM_STATE(state) case MEI_HBM_##state: return #state
  63         switch (state) {
  64         MEI_HBM_STATE(IDLE);
  65         MEI_HBM_STATE(STARTING);
  66         MEI_HBM_STATE(STARTED);
  67         MEI_HBM_STATE(ENUM_CLIENTS);
  68         MEI_HBM_STATE(CLIENT_PROPERTIES);
  69         MEI_HBM_STATE(STOPPED);
  70         default:
  71                 return "unknown";
  72         }
  73 #undef MEI_HBM_STATE
  74 }
  75
  76 /**
  77  * mei_cl_conn_status_to_errno - convert client connect response
  78  * status to error code
  79  *
  80  * @status: client connect response status
  81  *
  82  * Return: corresponding error code
  83  */
  84 static int mei_cl_conn_status_to_errno(enum mei_cl_connect_status status)
  85 {
  86         switch (status) {
  87         case MEI_CL_CONN_SUCCESS:          return 0;
  88         case MEI_CL_CONN_NOT_FOUND:        return -ENOTTY;
  89         case MEI_CL_CONN_ALREADY_STARTED:  return -EBUSY;
  90         case MEI_CL_CONN_OUT_OF_RESOURCES: return -EBUSY;
  91         case MEI_CL_CONN_MESSAGE_SMALL:    return -EINVAL;
  92         default:                           return -EINVAL;
  93         }
  94 }
  95
  96 /**
  97  * mei_hbm_idle - set hbm to idle state
  98  *
  99  * @dev: the device structure
 100  */
 101 void mei_hbm_idle(struct mei_device *dev)
 102 {
 103         dev->init_clients_timer = 0;
 104         dev->hbm_state = MEI_HBM_IDLE;
 105 }
 106
 107 /**
 108  * mei_me_cl_remove_all - remove all me clients
 109  *
 110  * @dev: the device structure
 111  */
 112 static void mei_me_cl_remove_all(struct mei_device *dev)
 113 {
 114         struct mei_me_client *me_cl, *next;
 115
 116         list_for_each_entry_safe(me_cl, next, &dev->me_clients, list) {
 117                         list_del(&me_cl->list);
 118                         kfree(me_cl);
 119         }
 120 }
 121
 122 /**
 123  * mei_hbm_reset - reset hbm counters and book keeping data structurs
 124  *
 125  * @dev: the device structure
 126  */
 127 void mei_hbm_reset(struct mei_device *dev)
 128 {
 129         dev->me_client_index = 0;
 130
 131         mei_me_cl_remove_all(dev);
 132
 133         mei_hbm_idle(dev);
 134 }
 135
 136 /**
 137  * mei_hbm_hdr - construct hbm header
 138  *
 139  * @hdr: hbm header
 140  * @length: payload length
 141  */
 142
 143 static inline void mei_hbm_hdr(struct mei_msg_hdr *hdr, size_t length)
 144 {
 145         hdr->host_addr = 0;
 146         hdr->me_addr = 0;
 147         hdr->length = length;
 148         hdr->msg_complete = 1;
 149         hdr->reserved = 0;
 150 }
 151
 152 /**
 153  * mei_hbm_cl_hdr - construct client hbm header
 154  *
 155  * @cl: client
 156  * @hbm_cmd: host bus message command
 157  * @buf: buffer for cl header
 158  * @len: buffer length
 159  */
 160 static inline
 161 void mei_hbm_cl_hdr(struct mei_cl *cl, u8 hbm_cmd, void *buf, size_t len)
 162 {
 163         struct mei_hbm_cl_cmd *cmd = buf;
 164
 165         memset(cmd, 0, len);
 166
 167         cmd->hbm_cmd = hbm_cmd;
 168         cmd->host_addr = cl->host_client_id;
 169         cmd->me_addr = cl->me_client_id;
 170 }
 171
 172 /**
 173  * mei_hbm_cl_write - write simple hbm client message
 174  *
 175  * @dev: the device structure
 176  * @cl: client
 177  * @hbm_cmd: host bus message command
 178  * @len: buffer length
 179  *
 180  * Return: 0 on success, <0 on failure.
 181  */
 182 static inline
 183 int mei_hbm_cl_write(struct mei_device *dev,
 184                      struct mei_cl *cl, u8 hbm_cmd, size_t len)
 185 {
 186         struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
 187
 188         mei_hbm_hdr(mei_hdr, len);
 189         mei_hbm_cl_hdr(cl, hbm_cmd, dev->wr_msg.data, len);
 190
 191         return mei_write_message(dev, mei_hdr, dev->wr_msg.data);
 192 }
 193
 194 /**
 195  * mei_hbm_cl_addr_equal - check if the client's and
 196  *      the message address match
 197  *
 198  * @cl: client
 199  * @cmd: hbm client message
 200  *
 201  * Return: true if addresses are the same
 202  */
 203 static inline
 204 bool mei_hbm_cl_addr_equal(struct mei_cl *cl, struct mei_hbm_cl_cmd *cmd)
 205 {
 206         return cl->host_client_id == cmd->host_addr &&
 207                 cl->me_client_id == cmd->me_addr;
 208 }
 209
 210 /**
 211  * mei_hbm_cl_find_by_cmd - find recipient client
 212  *
 213  * @dev: the device structure
 214  * @buf: a buffer with hbm cl command
 215  *
 216  * Return: the recipient client or NULL if not found
 217  */
 218 static inline
 219 struct mei_cl *mei_hbm_cl_find_by_cmd(struct mei_device *dev, void *buf)
 220 {
 221         struct mei_hbm_cl_cmd *cmd = (struct mei_hbm_cl_cmd *)buf;
 222         struct mei_cl *cl;
 223
 224         list_for_each_entry(cl, &dev->file_list, link)
 225                 if (mei_hbm_cl_addr_equal(cl, cmd))
 226                         return cl;
 227         return NULL;
 228 }
 229
 230
 231 /**
 232  * mei_hbm_start_wait - wait for start response message.
 233  *
 234  * @dev: the device structure
 235  *
 236  * Return: 0 on success and < 0 on failure
 237  */
 238 int mei_hbm_start_wait(struct mei_device *dev)
 239 {
 240         int ret;
 241
 242         if (dev->hbm_state > MEI_HBM_STARTING)
 243                 return 0;
 244
 245         mutex_unlock(&dev->device_lock);
 246         ret = wait_event_timeout(dev->wait_hbm_start,
 247                         dev->hbm_state != MEI_HBM_STARTING,
 248                         mei_secs_to_jiffies(MEI_HBM_TIMEOUT));
 249         mutex_lock(&dev->device_lock);
 250
 251         if (ret == 0 && (dev->hbm_state <= MEI_HBM_STARTING)) {
 252                 dev->hbm_state = MEI_HBM_IDLE;
 253                 dev_err(dev->dev, "waiting for mei start failed\n");
 254                 return -ETIME;
 255         }
 256         return 0;
 257 }
 258
 259 /**
 260  * mei_hbm_start_req - sends start request message.
 261  *
 262  * @dev: the device structure
 263  *
 264  * Return: 0 on success and < 0 on failure
 265  */
 266 int mei_hbm_start_req(struct mei_device *dev)
 267 {
 268         struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
 269         struct hbm_host_version_request *start_req;
 270         const size_t len = sizeof(struct hbm_host_version_request);
 271         int ret;
 272
 273         mei_hbm_reset(dev);
 274
 275         mei_hbm_hdr(mei_hdr, len);
 276
 277         /* host start message */
 278         start_req = (struct hbm_host_version_request *)dev->wr_msg.data;
 279         memset(start_req, 0, len);
 280         start_req->hbm_cmd = HOST_START_REQ_CMD;
 281         start_req->host_version.major_version = HBM_MAJOR_VERSION;
 282         start_req->host_version.minor_version = HBM_MINOR_VERSION;
 283
 284         dev->hbm_state = MEI_HBM_IDLE;
 285         ret = mei_write_message(dev, mei_hdr, dev->wr_msg.data);
 286         if (ret) {
 287                 dev_err(dev->dev, "version message write failed: ret = %d\n",
 288                         ret);
 289                 return ret;
 290         }
 291
 292         dev->hbm_state = MEI_HBM_STARTING;
 293         dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
 294         return 0;
 295 }
 296
 297 /*
 298  * mei_hbm_enum_clients_req - sends enumeration client request message.
 299  *
 300  * @dev: the device structure
 301  *
 302  * Return: 0 on success and < 0 on failure
 303  */
 304 static int mei_hbm_enum_clients_req(struct mei_device *dev)
 305 {
 306         struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
 307         struct hbm_host_enum_request *enum_req;
 308         const size_t len = sizeof(struct hbm_host_enum_request);
 309         int ret;
 310
 311         /* enumerate clients */
 312         mei_hbm_hdr(mei_hdr, len);
 313
 314         enum_req = (struct hbm_host_enum_request *)dev->wr_msg.data;
 315         memset(enum_req, 0, len);
 316         enum_req->hbm_cmd = HOST_ENUM_REQ_CMD;
 317
 318         ret = mei_write_message(dev, mei_hdr, dev->wr_msg.data);
 319         if (ret) {
 320                 dev_err(dev->dev, "enumeration request write failed: ret = %d.\n",
 321                         ret);
 322                 return ret;
 323         }
 324         dev->hbm_state = MEI_HBM_ENUM_CLIENTS;
 325         dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
 326         return 0;
 327 }
 328
 329 /*
 330  * mei_hbm_me_cl_add - add new me client to the list
 331  *
 332  * @dev: the device structure
 333  * @res: hbm property response
 334  *
 335  * Return: 0 on success and -ENOMEM on allocation failure
 336  */
 337
 338 static int mei_hbm_me_cl_add(struct mei_device *dev,
 339                              struct hbm_props_response *res)
 340 {
 341         struct mei_me_client *me_cl;
 342
 343         me_cl = kzalloc(sizeof(struct mei_me_client), GFP_KERNEL);
 344         if (!me_cl)
 345                 return -ENOMEM;
 346
 347         me_cl->props = res->client_properties;
 348         me_cl->client_id = res->me_addr;
 349         me_cl->mei_flow_ctrl_creds = 0;
 350
 351         list_add(&me_cl->list, &dev->me_clients);
 352         return 0;
 353 }
 354
 355 /**
 356  * mei_hbm_prop_req - request property for a single client
 357  *
 358  * @dev: the device structure
 359  *
 360  * Return: 0 on success and < 0 on failure
 361  */
 362
 363 static int mei_hbm_prop_req(struct mei_device *dev)
 364 {
 365
 366         struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
 367         struct hbm_props_request *prop_req;
 368         const size_t len = sizeof(struct hbm_props_request);
 369         unsigned long next_client_index;
 370         int ret;
 371
 372         next_client_index = find_next_bit(dev->me_clients_map, MEI_CLIENTS_MAX,
 373                                           dev->me_client_index);
 374
 375         /* We got all client properties */
 376         if (next_client_index == MEI_CLIENTS_MAX) {
 377                 dev->hbm_state = MEI_HBM_STARTED;
 378                 schedule_work(&dev->init_work);
 379
 380                 return 0;
 381         }
 382
 383         mei_hbm_hdr(mei_hdr, len);
 384         prop_req = (struct hbm_props_request *)dev->wr_msg.data;
 385
 386         memset(prop_req, 0, sizeof(struct hbm_props_request));
 387
 388         prop_req->hbm_cmd = HOST_CLIENT_PROPERTIES_REQ_CMD;
 389         prop_req->me_addr = next_client_index;
 390
 391         ret = mei_write_message(dev, mei_hdr, dev->wr_msg.data);
 392         if (ret) {
 393                 dev_err(dev->dev, "properties request write failed: ret = %d\n",
 394                         ret);
 395                 return ret;
 396         }
 397
 398         dev->init_clients_timer = MEI_CLIENTS_INIT_TIMEOUT;
 399         dev->me_client_index = next_client_index;
 400
 401         return 0;
 402 }
 403
 404 /*
 405  * mei_hbm_pg - sends pg command
 406  *
 407  * @dev: the device structure
 408  * @pg_cmd: the pg command code
 409  *
 410  * Return: -EIO on write failure
 411  *         -EOPNOTSUPP if the operation is not supported by the protocol
 412  */
 413 int mei_hbm_pg(struct mei_device *dev, u8 pg_cmd)
 414 {
 415         struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
 416         struct hbm_power_gate *req;
 417         const size_t len = sizeof(struct hbm_power_gate);
 418         int ret;
 419
 420         if (!dev->hbm_f_pg_supported)
 421                 return -EOPNOTSUPP;
 422
 423         mei_hbm_hdr(mei_hdr, len);
 424
 425         req = (struct hbm_power_gate *)dev->wr_msg.data;
 426         memset(req, 0, len);
 427         req->hbm_cmd = pg_cmd;
 428
 429         ret = mei_write_message(dev, mei_hdr, dev->wr_msg.data);
 430         if (ret)
 431                 dev_err(dev->dev, "power gate command write failed.\n");
 432         return ret;
 433 }
 434 EXPORT_SYMBOL_GPL(mei_hbm_pg);
 435
 436 /**
 437  * mei_hbm_stop_req - send stop request message
 438  *
 439  * @dev: mei device
 440  *
 441  * Return: -EIO on write failure
 442  */
 443 static int mei_hbm_stop_req(struct mei_device *dev)
 444 {
 445         struct mei_msg_hdr *mei_hdr = &dev->wr_msg.hdr;
 446         struct hbm_host_stop_request *req =
 447                         (struct hbm_host_stop_request *)dev->wr_msg.data;
 448         const size_t len = sizeof(struct hbm_host_stop_request);
 449
 450         mei_hbm_hdr(mei_hdr, len);
 451
 452         memset(req, 0, len);
 453         req->hbm_cmd = HOST_STOP_REQ_CMD;
 454         req->reason = DRIVER_STOP_REQUEST;
 455
 456         return mei_write_message(dev, mei_hdr, dev->wr_msg.data);
 457 }
 458
 459 /**
 460  * mei_hbm_cl_flow_control_req - sends flow control request.
 461  *
 462  * @dev: the device structure
 463  * @cl: client info
 464  *
 465  * Return: -EIO on write failure
 466  */
 467 int mei_hbm_cl_flow_control_req(struct mei_device *dev, struct mei_cl *cl)
 468 {
 469         const size_t len = sizeof(struct hbm_flow_control);
 470
 471         cl_dbg(dev, cl, "sending flow control\n");
 472         return mei_hbm_cl_write(dev, cl, MEI_FLOW_CONTROL_CMD, len);
 473 }
 474
 475 /**
 476  * mei_hbm_add_single_flow_creds - adds single buffer credentials.
 477  *
 478  * @dev: the device structure
 479  * @flow: flow control.
 480  *
 481  * Return: 0 on success, < 0 otherwise
 482  */
 483 static int mei_hbm_add_single_flow_creds(struct mei_device *dev,
 484                                   struct hbm_flow_control *flow)
 485 {
 486         struct mei_me_client *me_cl;
 487
 488         me_cl = mei_me_cl_by_id(dev, flow->me_addr);
 489         if (!me_cl) {
 490                 dev_err(dev->dev, "no such me client %d\n",
 491                         flow->me_addr);
 492                 return -ENOENT;
 493         }
 494
 495         if (WARN_ON(me_cl->props.single_recv_buf == 0))
 496                 return -EINVAL;
 497
 498         me_cl->mei_flow_ctrl_creds++;
 499         dev_dbg(dev->dev, "recv flow ctrl msg ME %d (single) creds = %d.\n",
 500             flow->me_addr, me_cl->mei_flow_ctrl_creds);
 501
 502         return 0;
 503 }
 504
 505 /**
 506  * mei_hbm_cl_flow_control_res - flow control response from me
 507  *
 508  * @dev: the device structure
 509  * @flow_control: flow control response bus message
 510  */
 511 static void mei_hbm_cl_flow_control_res(struct mei_device *dev,
 512                                         struct hbm_flow_control *flow_control)
 513 {
 514         struct mei_cl *cl;
 515
 516         if (!flow_control->host_addr) {
 517                 /* single receive buffer */
 518                 mei_hbm_add_single_flow_creds(dev, flow_control);
 519                 return;
 520         }
 521
 522         cl = mei_hbm_cl_find_by_cmd(dev, flow_control);
 523         if (cl) {
 524                 cl->mei_flow_ctrl_creds++;
 525                 cl_dbg(dev, cl, "flow control creds = %d.\n",
 526                                 cl->mei_flow_ctrl_creds);
 527         }
 528 }
 529
 530
 531 /**
 532  * mei_hbm_cl_disconnect_req - sends disconnect message to fw.
 533  *
 534  * @dev: the device structure
 535  * @cl: a client to disconnect from
 536  *
 537  * Return: -EIO on write failure
 538  */
 539 int mei_hbm_cl_disconnect_req(struct mei_device *dev, struct mei_cl *cl)
 540 {
 541         const size_t len = sizeof(struct hbm_client_connect_request);
 542
 543         return mei_hbm_cl_write(dev, cl, CLIENT_DISCONNECT_REQ_CMD, len);
 544 }
 545
 546 /**
 547  * mei_hbm_cl_disconnect_rsp - sends disconnect respose to the FW
 548  *
 549  * @dev: the device structure
 550  * @cl: a client to disconnect from
 551  *
 552  * Return: -EIO on write failure
 553  */
 554 int mei_hbm_cl_disconnect_rsp(struct mei_device *dev, struct mei_cl *cl)
 555 {
 556         const size_t len = sizeof(struct hbm_client_connect_response);
 557
 558         return mei_hbm_cl_write(dev, cl, CLIENT_DISCONNECT_RES_CMD, len);
 559 }
 560
 561 /**
 562  * mei_hbm_cl_disconnect_res - update the client state according
 563  *       disconnect response
 564  *
 565  * @cl: mei host client
 566  * @cmd: disconnect client response host bus message
 567  */
 568 static void mei_hbm_cl_disconnect_res(struct mei_cl *cl,
 569                                       struct mei_hbm_cl_cmd *cmd)
 570 {
 571         struct hbm_client_connect_response *rs =
 572                 (struct hbm_client_connect_response *)cmd;
 573
 574         dev_dbg(cl->dev->dev, "hbm: disconnect response cl:host=%02d me=%02d status=%d\n",
 575                         rs->me_addr, rs->host_addr, rs->status);
 576
 577         if (rs->status == MEI_CL_DISCONN_SUCCESS)
 578                 cl->state = MEI_FILE_DISCONNECTED;
 579         cl->status = 0;
 580 }
 581
 582 /**
 583  * mei_hbm_cl_connect_req - send connection request to specific me client
 584  *
 585  * @dev: the device structure
 586  * @cl: a client to connect to
 587  *
 588  * Return: -EIO on write failure
 589  */
 590 int mei_hbm_cl_connect_req(struct mei_device *dev, struct mei_cl *cl)
 591 {
 592         const size_t len = sizeof(struct hbm_client_connect_request);
 593
 594         return mei_hbm_cl_write(dev, cl, CLIENT_CONNECT_REQ_CMD, len);
 595 }
 596
 597 /**
 598  * mei_hbm_cl_connect_res - update the client state according
 599  *        connection response
 600  *
 601  * @cl: mei host client
 602  * @cmd: connect client response host bus message
 603  */
 604 static void mei_hbm_cl_connect_res(struct mei_cl *cl,
 605                                    struct mei_hbm_cl_cmd *cmd)
 606 {
 607         struct hbm_client_connect_response *rs =
 608                 (struct hbm_client_connect_response *)cmd;
 609
 610         dev_dbg(cl->dev->dev, "hbm: connect response cl:host=%02d me=%02d status=%s\n",
 611                         rs->me_addr, rs->host_addr,
 612                         mei_cl_conn_status_str(rs->status));
 613
 614         if (rs->status == MEI_CL_CONN_SUCCESS)
 615                 cl->state = MEI_FILE_CONNECTED;
 616         else
 617                 cl->state = MEI_FILE_DISCONNECTED;
 618         cl->status = mei_cl_conn_status_to_errno(rs->status);
 619 }
 620
 621 /**
 622  * mei_hbm_cl_res - process hbm response received on behalf
 623  *         an client
 624  *
 625  * @dev: the device structure
 626  * @rs:  hbm client message
 627  * @fop_type: file operation type
 628  */
 629 static void mei_hbm_cl_res(struct mei_device *dev,
 630                            struct mei_hbm_cl_cmd *rs,
 631                            enum mei_cb_file_ops fop_type)
 632 {
 633         struct mei_cl *cl;
 634         struct mei_cl_cb *cb, *next;
 635
 636         cl = NULL;
 637         list_for_each_entry_safe(cb, next, &dev->ctrl_rd_list.list, list) {
 638
 639                 cl = cb->cl;
 640                 /* this should not happen */
 641                 if (WARN_ON(!cl)) {
 642                         list_del_init(&cb->list);
 643                         continue;
 644                 }
 645
 646                 if (cb->fop_type != fop_type)
 647                         continue;
 648
 649                 if (mei_hbm_cl_addr_equal(cl, rs)) {
 650                         list_del(&cb->list);
 651                         break;
 652                 }
 653         }
 654
 655         if (!cl)
 656                 return;
 657
 658         switch (fop_type) {
 659         case MEI_FOP_CONNECT:
 660                 mei_hbm_cl_connect_res(cl, rs);
 661                 break;
 662         case MEI_FOP_DISCONNECT:
 663                 mei_hbm_cl_disconnect_res(cl, rs);
 664                 break;
 665         default:
 666                 return;
 667         }
 668
 669         cl->timer_count = 0;
 670         wake_up(&cl->wait);
 671 }
 672
 673
 674 /**
 675  * mei_hbm_fw_disconnect_req - disconnect request initiated by ME firmware
 676  *  host sends disconnect response
 677  *
 678  * @dev: the device structure.
 679  * @disconnect_req: disconnect request bus message from the me
 680  *
 681  * Return: -ENOMEM on allocation failure
 682  */
 683 static int mei_hbm_fw_disconnect_req(struct mei_device *dev,
 684                 struct hbm_client_connect_request *disconnect_req)
 685 {
 686         struct mei_cl *cl;
 687         struct mei_cl_cb *cb;
 688
 689         cl = mei_hbm_cl_find_by_cmd(dev, disconnect_req);
 690         if (cl) {
 691                 cl_dbg(dev, cl, "disconnect request received\n");
 692                 cl->state = MEI_FILE_DISCONNECTED;
 693                 cl->timer_count = 0;
 694
 695                 cb = mei_io_cb_init(cl, NULL);
 696                 if (!cb)
 697                         return -ENOMEM;
 698                 cb->fop_type = MEI_FOP_DISCONNECT_RSP;
 699                 cl_dbg(dev, cl, "add disconnect response as first\n");
 700                 list_add(&cb->list, &dev->ctrl_wr_list.list);
 701         }
 702         return 0;
 703 }
 704
 705 /**
 706  * mei_hbm_config_features - check what hbm features and commands
 707  *        are supported by the fw
 708  *
 709  * @dev: the device structure
 710  */
 711 static void mei_hbm_config_features(struct mei_device *dev)
 712 {
 713         /* Power Gating Isolation Support */
 714         dev->hbm_f_pg_supported = 0;
 715         if (dev->version.major_version > HBM_MAJOR_VERSION_PGI)
 716                 dev->hbm_f_pg_supported = 1;
 717
 718         if (dev->version.major_version == HBM_MAJOR_VERSION_PGI &&
 719             dev->version.minor_version >= HBM_MINOR_VERSION_PGI)
 720                 dev->hbm_f_pg_supported = 1;
 721 }
 722
 723 /**
 724  * mei_hbm_version_is_supported - checks whether the driver can
 725  *     support the hbm version of the device
 726  *
 727  * @dev: the device structure
 728  * Return: true if driver can support hbm version of the device
 729  */
 730 bool mei_hbm_version_is_supported(struct mei_device *dev)
 731 {
 732         return  (dev->version.major_version < HBM_MAJOR_VERSION) ||
 733                 (dev->version.major_version == HBM_MAJOR_VERSION &&
 734                  dev->version.minor_version <= HBM_MINOR_VERSION);
 735 }
 736
 737 /**
 738  * mei_hbm_dispatch - bottom half read routine after ISR to
 739  * handle the read bus message cmd processing.
 740  *
 741  * @dev: the device structure
 742  * @hdr: header of bus message
 743  *
 744  * Return: 0 on success and < 0 on failure
 745  */
 746 int mei_hbm_dispatch(struct mei_device *dev, struct mei_msg_hdr *hdr)
 747 {
 748         struct mei_bus_message *mei_msg;
 749         struct hbm_host_version_response *version_res;
 750         struct hbm_props_response *props_res;
 751         struct hbm_host_enum_response *enum_res;
 752
 753         struct mei_hbm_cl_cmd *cl_cmd;
 754         struct hbm_client_connect_request *disconnect_req;
 755         struct hbm_flow_control *flow_control;
 756
 757         /* read the message to our buffer */
 758         BUG_ON(hdr->length >= sizeof(dev->rd_msg_buf));
 759         mei_read_slots(dev, dev->rd_msg_buf, hdr->length);
 760         mei_msg = (struct mei_bus_message *)dev->rd_msg_buf;
 761         cl_cmd  = (struct mei_hbm_cl_cmd *)mei_msg;
 762
 763         /* ignore spurious message and prevent reset nesting
 764          * hbm is put to idle during system reset
 765          */
 766         if (dev->hbm_state == MEI_HBM_IDLE) {
 767                 dev_dbg(dev->dev, "hbm: state is idle ignore spurious messages\n");
 768                 return 0;
 769         }
 770
 771         switch (mei_msg->hbm_cmd) {
 772         case HOST_START_RES_CMD:
 773                 dev_dbg(dev->dev, "hbm: start: response message received.\n");
 774
 775                 dev->init_clients_timer = 0;
 776
 777                 version_res = (struct hbm_host_version_response *)mei_msg;
 778
 779                 dev_dbg(dev->dev, "HBM VERSION: DRIVER=%02d:%02d DEVICE=%02d:%02d\n",
 780                                 HBM_MAJOR_VERSION, HBM_MINOR_VERSION,
 781                                 version_res->me_max_version.major_version,
 782                                 version_res->me_max_version.minor_version);
 783
 784                 if (version_res->host_version_supported) {
 785                         dev->version.major_version = HBM_MAJOR_VERSION;
 786                         dev->version.minor_version = HBM_MINOR_VERSION;
 787                 } else {
 788                         dev->version.major_version =
 789                                 version_res->me_max_version.major_version;
 790                         dev->version.minor_version =
 791                                 version_res->me_max_version.minor_version;
 792                 }
 793
 794                 if (!mei_hbm_version_is_supported(dev)) {
 795                         dev_warn(dev->dev, "hbm: start: version mismatch - stopping the driver.\n");
 796
 797                         dev->hbm_state = MEI_HBM_STOPPED;
 798                         if (mei_hbm_stop_req(dev)) {
 799                                 dev_err(dev->dev, "hbm: start: failed to send stop request\n");
 800                                 return -EIO;
 801                         }
 802                         break;
 803                 }
 804
 805                 mei_hbm_config_features(dev);
 806
 807                 if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
 808                     dev->hbm_state != MEI_HBM_STARTING) {
 809                         dev_err(dev->dev, "hbm: start: state mismatch, [%d, %d]\n",
 810                                 dev->dev_state, dev->hbm_state);
 811                         return -EPROTO;
 812                 }
 813
 814                 dev->hbm_state = MEI_HBM_STARTED;
 815
 816                 if (mei_hbm_enum_clients_req(dev)) {
 817                         dev_err(dev->dev, "hbm: start: failed to send enumeration request\n");
 818                         return -EIO;
 819                 }
 820
 821                 wake_up(&dev->wait_hbm_start);
 822                 break;
 823
 824         case CLIENT_CONNECT_RES_CMD:
 825                 dev_dbg(dev->dev, "hbm: client connect response: message received.\n");
 826                 mei_hbm_cl_res(dev, cl_cmd, MEI_FOP_CONNECT);
 827                 break;
 828
 829         case CLIENT_DISCONNECT_RES_CMD:
 830                 dev_dbg(dev->dev, "hbm: client disconnect response: message received.\n");
 831                 mei_hbm_cl_res(dev, cl_cmd, MEI_FOP_DISCONNECT);
 832                 break;
 833
 834         case MEI_FLOW_CONTROL_CMD:
 835                 dev_dbg(dev->dev, "hbm: client flow control response: message received.\n");
 836
 837                 flow_control = (struct hbm_flow_control *) mei_msg;
 838                 mei_hbm_cl_flow_control_res(dev, flow_control);
 839                 break;
 840
 841         case MEI_PG_ISOLATION_ENTRY_RES_CMD:
 842                 dev_dbg(dev->dev, "power gate isolation entry response received\n");
 843                 dev->pg_event = MEI_PG_EVENT_RECEIVED;
 844                 if (waitqueue_active(&dev->wait_pg))
 845                         wake_up(&dev->wait_pg);
 846                 break;
 847
 848         case MEI_PG_ISOLATION_EXIT_REQ_CMD:
 849                 dev_dbg(dev->dev, "power gate isolation exit request received\n");
 850                 dev->pg_event = MEI_PG_EVENT_RECEIVED;
 851                 if (waitqueue_active(&dev->wait_pg))
 852                         wake_up(&dev->wait_pg);
 853                 else
 854                         /*
 855                         * If the driver is not waiting on this then
 856                         * this is HW initiated exit from PG.
 857                         * Start runtime pm resume sequence to exit from PG.
 858                         */
 859                         pm_request_resume(dev->dev);
 860                 break;
 861
 862         case HOST_CLIENT_PROPERTIES_RES_CMD:
 863                 dev_dbg(dev->dev, "hbm: properties response: message received.\n");
 864
 865                 dev->init_clients_timer = 0;
 866
 867                 if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
 868                     dev->hbm_state != MEI_HBM_CLIENT_PROPERTIES) {
 869                         dev_err(dev->dev, "hbm: properties response: state mismatch, [%d, %d]\n",
 870                                 dev->dev_state, dev->hbm_state);
 871                         return -EPROTO;
 872                 }
 873
 874                 props_res = (struct hbm_props_response *)mei_msg;
 875
 876                 if (props_res->status) {
 877                         dev_err(dev->dev, "hbm: properties response: wrong status = %d %s\n",
 878                                 props_res->status,
 879                                 mei_hbm_status_str(props_res->status));
 880                         return -EPROTO;
 881                 }
 882
 883                 mei_hbm_me_cl_add(dev, props_res);
 884
 885                 dev->me_client_index++;
 886
 887                 /* request property for the next client */
 888                 if (mei_hbm_prop_req(dev))
 889                         return -EIO;
 890
 891                 break;
 892
 893         case HOST_ENUM_RES_CMD:
 894                 dev_dbg(dev->dev, "hbm: enumeration response: message received\n");
 895
 896                 dev->init_clients_timer = 0;
 897
 898                 enum_res = (struct hbm_host_enum_response *) mei_msg;
 899                 BUILD_BUG_ON(sizeof(dev->me_clients_map)
 900                                 < sizeof(enum_res->valid_addresses));
 901                 memcpy(dev->me_clients_map, enum_res->valid_addresses,
 902                                 sizeof(enum_res->valid_addresses));
 903
 904                 if (dev->dev_state != MEI_DEV_INIT_CLIENTS ||
 905                     dev->hbm_state != MEI_HBM_ENUM_CLIENTS) {
 906                         dev_err(dev->dev, "hbm: enumeration response: state mismatch, [%d, %d]\n",
 907                                 dev->dev_state, dev->hbm_state);
 908                         return -EPROTO;
 909                 }
 910
 911                 dev->hbm_state = MEI_HBM_CLIENT_PROPERTIES;
 912
 913                 /* first property request */
 914                 if (mei_hbm_prop_req(dev))
 915                         return -EIO;
 916
 917                 break;
 918
 919         case HOST_STOP_RES_CMD:
 920                 dev_dbg(dev->dev, "hbm: stop response: message received\n");
 921
 922                 dev->init_clients_timer = 0;
 923
 924                 if (dev->hbm_state != MEI_HBM_STOPPED) {
 925                         dev_err(dev->dev, "hbm: stop response: state mismatch, [%d, %d]\n",
 926                                 dev->dev_state, dev->hbm_state);
 927                         return -EPROTO;
 928                 }
 929
 930                 dev->dev_state = MEI_DEV_POWER_DOWN;
 931                 dev_info(dev->dev, "hbm: stop response: resetting.\n");
 932                 /* force the reset */
 933                 return -EPROTO;
 934                 break;
 935
 936         case CLIENT_DISCONNECT_REQ_CMD:
 937                 dev_dbg(dev->dev, "hbm: disconnect request: message received\n");
 938
 939                 disconnect_req = (struct hbm_client_connect_request *)mei_msg;
 940                 mei_hbm_fw_disconnect_req(dev, disconnect_req);
 941                 break;
 942
 943         case ME_STOP_REQ_CMD:
 944                 dev_dbg(dev->dev, "hbm: stop request: message received\n");
 945                 dev->hbm_state = MEI_HBM_STOPPED;
 946                 if (mei_hbm_stop_req(dev)) {
 947                         dev_err(dev->dev, "hbm: stop request: failed to send stop request\n");
 948                         return -EIO;
 949                 }
 950                 break;
 951         default:
 952                 BUG();
 953                 break;
 954
 955         }
 956         return 0;
 957 }
 958