drivers/misc/mei/interrupt.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
  18 #include <linux/export.h>
  19 #include <linux/kthread.h>
  20 #include <linux/interrupt.h>
  21 #include <linux/fs.h>
  22 #include <linux/jiffies.h>
  23 #include <linux/slab.h>
  24
  25 #include <linux/mei.h>
  26
  27 #include "mei_dev.h"
  28 #include "hbm.h"
  29 #include "client.h"
  30
  31
  32 /**
  33  * mei_irq_compl_handler - dispatch complete handlers
  34  *      for the completed callbacks
  35  *
  36  * @dev: mei device
  37  * @compl_list: list of completed cbs
  38  */
  39 void mei_irq_compl_handler(struct mei_device *dev, struct mei_cl_cb *compl_list)
  40 {
  41         struct mei_cl_cb *cb, *next;
  42         struct mei_cl *cl;
  43
  44         list_for_each_entry_safe(cb, next, &compl_list->list, list) {
  45                 cl = cb->cl;
  46                 list_del(&cb->list);
  47                 if (!cl)
  48                         continue;
  49
  50                 dev_dbg(dev->dev, "completing call back.\n");
  51                 if (cl == &dev->iamthif_cl)
  52                         mei_amthif_complete(dev, cb);
  53                 else
  54                         mei_cl_complete(cl, cb);
  55         }
  56 }
  57 EXPORT_SYMBOL_GPL(mei_irq_compl_handler);
  58
  59 /**
  60  * mei_cl_hbm_equal - check if hbm is addressed to the client
  61  *
  62  * @cl: host client
  63  * @mei_hdr: header of mei client message
  64  *
  65  * Return: true if matches, false otherwise
  66  */
  67 static inline int mei_cl_hbm_equal(struct mei_cl *cl,
  68                         struct mei_msg_hdr *mei_hdr)
  69 {
  70         return cl->host_client_id == mei_hdr->host_addr &&
  71                 cl->me_client_id == mei_hdr->me_addr;
  72 }
  73 /**
  74  * mei_cl_is_reading - checks if the client
  75  *              is the one to read this message
  76  *
  77  * @cl: mei client
  78  * @mei_hdr: header of mei message
  79  *
  80  * Return: true on match and false otherwise
  81  */
  82 static bool mei_cl_is_reading(struct mei_cl *cl, struct mei_msg_hdr *mei_hdr)
  83 {
  84         return mei_cl_hbm_equal(cl, mei_hdr) &&
  85                 cl->state == MEI_FILE_CONNECTED &&
  86                 cl->reading_state != MEI_READ_COMPLETE;
  87 }
  88
  89 /**
  90  * mei_cl_irq_read_msg - process client message
  91  *
  92  * @dev: the device structure
  93  * @mei_hdr: header of mei client message
  94  * @complete_list: An instance of our list structure
  95  *
  96  * Return: 0 on success, <0 on failure.
  97  */
  98 static int mei_cl_irq_read_msg(struct mei_device *dev,
  99                                struct mei_msg_hdr *mei_hdr,
 100                                struct mei_cl_cb *complete_list)
 101 {
 102         struct mei_cl *cl;
 103         struct mei_cl_cb *cb, *next;
 104         unsigned char *buffer = NULL;
 105
 106         list_for_each_entry_safe(cb, next, &dev->read_list.list, list) {
 107                 cl = cb->cl;
 108                 if (!cl || !mei_cl_is_reading(cl, mei_hdr))
 109                         continue;
 110
 111                 cl->reading_state = MEI_READING;
 112
 113                 if (cb->response_buffer.size == 0 ||
 114                     cb->response_buffer.data == NULL) {
 115                         cl_err(dev, cl, "response buffer is not allocated.\n");
 116                         list_del(&cb->list);
 117                         return -ENOMEM;
 118                 }
 119
 120                 if (cb->response_buffer.size < mei_hdr->length + cb->buf_idx) {
 121                         cl_dbg(dev, cl, "message overflow. size %d len %d idx %ld\n",
 122                                 cb->response_buffer.size,
 123                                 mei_hdr->length, cb->buf_idx);
 124                         buffer = krealloc(cb->response_buffer.data,
 125                                           mei_hdr->length + cb->buf_idx,
 126                                           GFP_KERNEL);
 127
 128                         if (!buffer) {
 129                                 list_del(&cb->list);
 130                                 return -ENOMEM;
 131                         }
 132                         cb->response_buffer.data = buffer;
 133                         cb->response_buffer.size =
 134                                 mei_hdr->length + cb->buf_idx;
 135                 }
 136
 137                 buffer = cb->response_buffer.data + cb->buf_idx;
 138                 mei_read_slots(dev, buffer, mei_hdr->length);
 139
 140                 cb->buf_idx += mei_hdr->length;
 141                 if (mei_hdr->msg_complete) {
 142                         cl->status = 0;
 143                         list_del(&cb->list);
 144                         cl_dbg(dev, cl, "completed read length = %lu\n",
 145                                 cb->buf_idx);
 146                         list_add_tail(&cb->list, &complete_list->list);
 147                 }
 148                 break;
 149         }
 150
 151         dev_dbg(dev->dev, "message read\n");
 152         if (!buffer) {
 153                 mei_read_slots(dev, dev->rd_msg_buf, mei_hdr->length);
 154                 dev_dbg(dev->dev, "discarding message " MEI_HDR_FMT "\n",
 155                                 MEI_HDR_PRM(mei_hdr));
 156         }
 157
 158         return 0;
 159 }
 160
 161 /**
 162  * mei_cl_irq_disconnect_rsp - send disconnection response message
 163  *
 164  * @cl: client
 165  * @cb: callback block.
 166  * @cmpl_list: complete list.
 167  *
 168  * Return: 0, OK; otherwise, error.
 169  */
 170 static int mei_cl_irq_disconnect_rsp(struct mei_cl *cl, struct mei_cl_cb *cb,
 171                                      struct mei_cl_cb *cmpl_list)
 172 {
 173         struct mei_device *dev = cl->dev;
 174         u32 msg_slots;
 175         int slots;
 176         int ret;
 177
 178         slots = mei_hbuf_empty_slots(dev);
 179         msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_response));
 180
 181         if (slots < msg_slots)
 182                 return -EMSGSIZE;
 183
 184         ret = mei_hbm_cl_disconnect_rsp(dev, cl);
 185
 186         cl->state = MEI_FILE_DISCONNECTED;
 187         cl->status = 0;
 188         list_del(&cb->list);
 189         mei_io_cb_free(cb);
 190
 191         return ret;
 192 }
 193
 194
 195
 196 /**
 197  * mei_cl_irq_disconnect - processes close related operation from
 198  *      interrupt thread context - send disconnect request
 199  *
 200  * @cl: client
 201  * @cb: callback block.
 202  * @cmpl_list: complete list.
 203  *
 204  * Return: 0, OK; otherwise, error.
 205  */
 206 static int mei_cl_irq_disconnect(struct mei_cl *cl, struct mei_cl_cb *cb,
 207                             struct mei_cl_cb *cmpl_list)
 208 {
 209         struct mei_device *dev = cl->dev;
 210         u32 msg_slots;
 211         int slots;
 212
 213         msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
 214         slots = mei_hbuf_empty_slots(dev);
 215
 216         if (slots < msg_slots)
 217                 return -EMSGSIZE;
 218
 219         if (mei_hbm_cl_disconnect_req(dev, cl)) {
 220                 cl->status = 0;
 221                 cb->buf_idx = 0;
 222                 list_move_tail(&cb->list, &cmpl_list->list);
 223                 return -EIO;
 224         }
 225
 226         cl->state = MEI_FILE_DISCONNECTING;
 227         cl->status = 0;
 228         cb->buf_idx = 0;
 229         list_move_tail(&cb->list, &dev->ctrl_rd_list.list);
 230         cl->timer_count = MEI_CONNECT_TIMEOUT;
 231
 232         return 0;
 233 }
 234
 235
 236 /**
 237  * mei_cl_irq_read - processes client read related operation from the
 238  *      interrupt thread context - request for flow control credits
 239  *
 240  * @cl: client
 241  * @cb: callback block.
 242  * @cmpl_list: complete list.
 243  *
 244  * Return: 0, OK; otherwise, error.
 245  */
 246 static int mei_cl_irq_read(struct mei_cl *cl, struct mei_cl_cb *cb,
 247                            struct mei_cl_cb *cmpl_list)
 248 {
 249         struct mei_device *dev = cl->dev;
 250         u32 msg_slots;
 251         int slots;
 252         int ret;
 253
 254         msg_slots = mei_data2slots(sizeof(struct hbm_flow_control));
 255         slots = mei_hbuf_empty_slots(dev);
 256
 257         if (slots < msg_slots)
 258                 return -EMSGSIZE;
 259
 260         ret = mei_hbm_cl_flow_control_req(dev, cl);
 261         if (ret) {
 262                 cl->status = ret;
 263                 cb->buf_idx = 0;
 264                 list_move_tail(&cb->list, &cmpl_list->list);
 265                 return ret;
 266         }
 267
 268         list_move_tail(&cb->list, &dev->read_list.list);
 269
 270         return 0;
 271 }
 272
 273
 274 /**
 275  * mei_cl_irq_connect - send connect request in irq_thread context
 276  *
 277  * @cl: client
 278  * @cb: callback block.
 279  * @cmpl_list: complete list.
 280  *
 281  * Return: 0, OK; otherwise, error.
 282  */
 283 static int mei_cl_irq_connect(struct mei_cl *cl, struct mei_cl_cb *cb,
 284                               struct mei_cl_cb *cmpl_list)
 285 {
 286         struct mei_device *dev = cl->dev;
 287         u32 msg_slots;
 288         int slots;
 289         int ret;
 290
 291         msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
 292         slots = mei_hbuf_empty_slots(dev);
 293
 294         if (mei_cl_is_other_connecting(cl))
 295                 return 0;
 296
 297         if (slots < msg_slots)
 298                 return -EMSGSIZE;
 299
 300         cl->state = MEI_FILE_CONNECTING;
 301
 302         ret = mei_hbm_cl_connect_req(dev, cl);
 303         if (ret) {
 304                 cl->status = ret;
 305                 cb->buf_idx = 0;
 306                 list_del(&cb->list);
 307                 return ret;
 308         }
 309
 310         list_move_tail(&cb->list, &dev->ctrl_rd_list.list);
 311         cl->timer_count = MEI_CONNECT_TIMEOUT;
 312         return 0;
 313 }
 314
 315
 316 /**
 317  * mei_irq_read_handler - bottom half read routine after ISR to
 318  * handle the read processing.
 319  *
 320  * @dev: the device structure
 321  * @cmpl_list: An instance of our list structure
 322  * @slots: slots to read.
 323  *
 324  * Return: 0 on success, <0 on failure.
 325  */
 326 int mei_irq_read_handler(struct mei_device *dev,
 327                 struct mei_cl_cb *cmpl_list, s32 *slots)
 328 {
 329         struct mei_msg_hdr *mei_hdr;
 330         struct mei_cl *cl;
 331         int ret;
 332
 333         if (!dev->rd_msg_hdr) {
 334                 dev->rd_msg_hdr = mei_read_hdr(dev);
 335                 (*slots)--;
 336                 dev_dbg(dev->dev, "slots =%08x.\n", *slots);
 337         }
 338         mei_hdr = (struct mei_msg_hdr *) &dev->rd_msg_hdr;
 339         dev_dbg(dev->dev, MEI_HDR_FMT, MEI_HDR_PRM(mei_hdr));
 340
 341         if (mei_hdr->reserved || !dev->rd_msg_hdr) {
 342                 dev_err(dev->dev, "corrupted message header 0x%08X\n",
 343                                 dev->rd_msg_hdr);
 344                 ret = -EBADMSG;
 345                 goto end;
 346         }
 347
 348         if (mei_slots2data(*slots) < mei_hdr->length) {
 349                 dev_err(dev->dev, "less data available than length=%08x.\n",
 350                                 *slots);
 351                 /* we can't read the message */
 352                 ret = -ENODATA;
 353                 goto end;
 354         }
 355
 356         /*  HBM message */
 357         if (mei_hdr->host_addr == 0 && mei_hdr->me_addr == 0) {
 358                 ret = mei_hbm_dispatch(dev, mei_hdr);
 359                 if (ret) {
 360                         dev_dbg(dev->dev, "mei_hbm_dispatch failed ret = %d\n",
 361                                         ret);
 362                         goto end;
 363                 }
 364                 goto reset_slots;
 365         }
 366
 367         /* find recipient cl */
 368         list_for_each_entry(cl, &dev->file_list, link) {
 369                 if (mei_cl_hbm_equal(cl, mei_hdr)) {
 370                         cl_dbg(dev, cl, "got a message\n");
 371                         break;
 372                 }
 373         }
 374
 375         /* if no recipient cl was found we assume corrupted header */
 376         if (&cl->link == &dev->file_list) {
 377                 dev_err(dev->dev, "no destination client found 0x%08X\n",
 378                                 dev->rd_msg_hdr);
 379                 ret = -EBADMSG;
 380                 goto end;
 381         }
 382
 383         if (mei_hdr->host_addr == dev->iamthif_cl.host_client_id &&
 384             MEI_FILE_CONNECTED == dev->iamthif_cl.state &&
 385             dev->iamthif_state == MEI_IAMTHIF_READING) {
 386
 387                 ret = mei_amthif_irq_read_msg(dev, mei_hdr, cmpl_list);
 388                 if (ret) {
 389                         dev_err(dev->dev, "mei_amthif_irq_read_msg failed = %d\n",
 390                                         ret);
 391                         goto end;
 392                 }
 393         } else {
 394                 ret = mei_cl_irq_read_msg(dev, mei_hdr, cmpl_list);
 395                 if (ret) {
 396                         dev_err(dev->dev, "mei_cl_irq_read_msg failed = %d\n",
 397                                         ret);
 398                         goto end;
 399                 }
 400         }
 401
 402 reset_slots:
 403         /* reset the number of slots and header */
 404         *slots = mei_count_full_read_slots(dev);
 405         dev->rd_msg_hdr = 0;
 406
 407         if (*slots == -EOVERFLOW) {
 408                 /* overflow - reset */
 409                 dev_err(dev->dev, "resetting due to slots overflow.\n");
 410                 /* set the event since message has been read */
 411                 ret = -ERANGE;
 412                 goto end;
 413         }
 414 end:
 415         return ret;
 416 }
 417 EXPORT_SYMBOL_GPL(mei_irq_read_handler);
 418
 419
 420 /**
 421  * mei_irq_write_handler -  dispatch write requests
 422  *  after irq received
 423  *
 424  * @dev: the device structure
 425  * @cmpl_list: An instance of our list structure
 426  *
 427  * Return: 0 on success, <0 on failure.
 428  */
 429 int mei_irq_write_handler(struct mei_device *dev, struct mei_cl_cb *cmpl_list)
 430 {
 431
 432         struct mei_cl *cl;
 433         struct mei_cl_cb *cb, *next;
 434         struct mei_cl_cb *list;
 435         s32 slots;
 436         int ret;
 437
 438
 439         if (!mei_hbuf_acquire(dev))
 440                 return 0;
 441
 442         slots = mei_hbuf_empty_slots(dev);
 443         if (slots <= 0)
 444                 return -EMSGSIZE;
 445
 446         /* complete all waiting for write CB */
 447         dev_dbg(dev->dev, "complete all waiting for write cb.\n");
 448
 449         list = &dev->write_waiting_list;
 450         list_for_each_entry_safe(cb, next, &list->list, list) {
 451                 cl = cb->cl;
 452                 if (cl == NULL)
 453                         continue;
 454
 455                 cl->status = 0;
 456                 list_del(&cb->list);
 457                 if (cb->fop_type == MEI_FOP_WRITE &&
 458                     cl != &dev->iamthif_cl) {
 459                         cl_dbg(dev, cl, "MEI WRITE COMPLETE\n");
 460                         cl->writing_state = MEI_WRITE_COMPLETE;
 461                         list_add_tail(&cb->list, &cmpl_list->list);
 462                 }
 463                 if (cl == &dev->iamthif_cl) {
 464                         cl_dbg(dev, cl, "check iamthif flow control.\n");
 465                         if (dev->iamthif_flow_control_pending) {
 466                                 ret = mei_amthif_irq_read(dev, &slots);
 467                                 if (ret)
 468                                         return ret;
 469                         }
 470                 }
 471         }
 472
 473         if (dev->wd_state == MEI_WD_STOPPING) {
 474                 dev->wd_state = MEI_WD_IDLE;
 475                 wake_up(&dev->wait_stop_wd);
 476         }
 477
 478         if (mei_cl_is_connected(&dev->wd_cl)) {
 479                 if (dev->wd_pending &&
 480                     mei_cl_flow_ctrl_creds(&dev->wd_cl) > 0) {
 481                         ret = mei_wd_send(dev);
 482                         if (ret)
 483                                 return ret;
 484                         dev->wd_pending = false;
 485                 }
 486         }
 487
 488         /* complete control write list CB */
 489         dev_dbg(dev->dev, "complete control write list cb.\n");
 490         list_for_each_entry_safe(cb, next, &dev->ctrl_wr_list.list, list) {
 491                 cl = cb->cl;
 492                 if (!cl) {
 493                         list_del(&cb->list);
 494                         return -ENODEV;
 495                 }
 496                 switch (cb->fop_type) {
 497                 case MEI_FOP_DISCONNECT:
 498                         /* send disconnect message */
 499                         ret = mei_cl_irq_disconnect(cl, cb, cmpl_list);
 500                         if (ret)
 501                                 return ret;
 502
 503                         break;
 504                 case MEI_FOP_READ:
 505                         /* send flow control message */
 506                         ret = mei_cl_irq_read(cl, cb, cmpl_list);
 507                         if (ret)
 508                                 return ret;
 509
 510                         break;
 511                 case MEI_FOP_CONNECT:
 512                         /* connect message */
 513                         ret = mei_cl_irq_connect(cl, cb, cmpl_list);
 514                         if (ret)
 515                                 return ret;
 516
 517                         break;
 518                 case MEI_FOP_DISCONNECT_RSP:
 519                         /* send disconnect resp */
 520                         ret = mei_cl_irq_disconnect_rsp(cl, cb, cmpl_list);
 521                         if (ret)
 522                                 return ret;
 523                         break;
 524                 default:
 525                         BUG();
 526                 }
 527
 528         }
 529         /* complete  write list CB */
 530         dev_dbg(dev->dev, "complete write list cb.\n");
 531         list_for_each_entry_safe(cb, next, &dev->write_list.list, list) {
 532                 cl = cb->cl;
 533                 if (cl == NULL)
 534                         continue;
 535                 if (cl == &dev->iamthif_cl)
 536                         ret = mei_amthif_irq_write(cl, cb, cmpl_list);
 537                 else
 538                         ret = mei_cl_irq_write(cl, cb, cmpl_list);
 539                 if (ret)
 540                         return ret;
 541         }
 542         return 0;
 543 }
 544 EXPORT_SYMBOL_GPL(mei_irq_write_handler);
 545
 546
 547
 548 /**
 549  * mei_timer - timer function.
 550  *
 551  * @work: pointer to the work_struct structure
 552  *
 553  */
 554 void mei_timer(struct work_struct *work)
 555 {
 556         unsigned long timeout;
 557         struct mei_cl *cl;
 558
 559         struct mei_device *dev = container_of(work,
 560                                         struct mei_device, timer_work.work);
 561
 562
 563         mutex_lock(&dev->device_lock);
 564
 565         /* Catch interrupt stalls during HBM init handshake */
 566         if (dev->dev_state == MEI_DEV_INIT_CLIENTS &&
 567             dev->hbm_state != MEI_HBM_IDLE) {
 568
 569                 if (dev->init_clients_timer) {
 570                         if (--dev->init_clients_timer == 0) {
 571                                 dev_err(dev->dev, "timer: init clients timeout hbm_state = %d.\n",
 572                                         dev->hbm_state);
 573                                 mei_reset(dev);
 574                                 goto out;
 575                         }
 576                 }
 577         }
 578
 579         if (dev->dev_state != MEI_DEV_ENABLED)
 580                 goto out;
 581
 582         /*** connect/disconnect timeouts ***/
 583         list_for_each_entry(cl, &dev->file_list, link) {
 584                 if (cl->timer_count) {
 585                         if (--cl->timer_count == 0) {
 586                                 dev_err(dev->dev, "timer: connect/disconnect timeout.\n");
 587                                 mei_reset(dev);
 588                                 goto out;
 589                         }
 590                 }
 591         }
 592
 593         if (!mei_cl_is_connected(&dev->iamthif_cl))
 594                 goto out;
 595
 596         if (dev->iamthif_stall_timer) {
 597                 if (--dev->iamthif_stall_timer == 0) {
 598                         dev_err(dev->dev, "timer: amthif  hanged.\n");
 599                         mei_reset(dev);
 600                         dev->iamthif_msg_buf_size = 0;
 601                         dev->iamthif_msg_buf_index = 0;
 602                         dev->iamthif_canceled = false;
 603                         dev->iamthif_ioctl = true;
 604                         dev->iamthif_state = MEI_IAMTHIF_IDLE;
 605                         dev->iamthif_timer = 0;
 606
 607                         mei_io_cb_free(dev->iamthif_current_cb);
 608                         dev->iamthif_current_cb = NULL;
 609
 610                         dev->iamthif_file_object = NULL;
 611                         mei_amthif_run_next_cmd(dev);
 612                 }
 613         }
 614
 615         if (dev->iamthif_timer) {
 616
 617                 timeout = dev->iamthif_timer +
 618                         mei_secs_to_jiffies(MEI_IAMTHIF_READ_TIMER);
 619
 620                 dev_dbg(dev->dev, "dev->iamthif_timer = %ld\n",
 621                                 dev->iamthif_timer);
 622                 dev_dbg(dev->dev, "timeout = %ld\n", timeout);
 623                 dev_dbg(dev->dev, "jiffies = %ld\n", jiffies);
 624                 if (time_after(jiffies, timeout)) {
 625                         /*
 626                          * User didn't read the AMTHI data on time (15sec)
 627                          * freeing AMTHI for other requests
 628                          */
 629
 630                         dev_dbg(dev->dev, "freeing AMTHI for other requests\n");
 631
 632                         mei_io_list_flush(&dev->amthif_rd_complete_list,
 633                                 &dev->iamthif_cl);
 634                         mei_io_cb_free(dev->iamthif_current_cb);
 635                         dev->iamthif_current_cb = NULL;
 636
 637                         dev->iamthif_file_object->private_data = NULL;
 638                         dev->iamthif_file_object = NULL;
 639                         dev->iamthif_timer = 0;
 640                         mei_amthif_run_next_cmd(dev);
 641
 642                 }
 643         }
 644 out:
 645         if (dev->dev_state != MEI_DEV_DISABLED)
 646                 schedule_delayed_work(&dev->timer_work, 2 * HZ);
 647         mutex_unlock(&dev->device_lock);
 648 }
 649