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/pci.h>
  20 #include <linux/kthread.h>
  21 #include <linux/interrupt.h>
  22 #include <linux/fs.h>
  23 #include <linux/jiffies.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->pdev->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  * returns 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  * returns 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_irq_read_client_message - 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  * returns 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                                 cl_err(dev, cl, "allocation failed.\n");
 130                                 list_del(&cb->list);
 131                                 return -ENOMEM;
 132                         }
 133                         cb->response_buffer.data = buffer;
 134                         cb->response_buffer.size =
 135                                 mei_hdr->length + cb->buf_idx;
 136                 }
 137
 138                 buffer = cb->response_buffer.data + cb->buf_idx;
 139                 mei_read_slots(dev, buffer, mei_hdr->length);
 140
 141                 cb->buf_idx += mei_hdr->length;
 142                 if (mei_hdr->msg_complete) {
 143                         cl->status = 0;
 144                         list_del(&cb->list);
 145                         cl_dbg(dev, cl, "completed read length = %lu\n",
 146                                 cb->buf_idx);
 147                         list_add_tail(&cb->list, &complete_list->list);
 148                 }
 149                 break;
 150         }
 151
 152         dev_dbg(&dev->pdev->dev, "message read\n");
 153         if (!buffer) {
 154                 mei_read_slots(dev, dev->rd_msg_buf, mei_hdr->length);
 155                 dev_dbg(&dev->pdev->dev, "discarding message " MEI_HDR_FMT "\n",
 156                                 MEI_HDR_PRM(mei_hdr));
 157         }
 158
 159         return 0;
 160 }
 161
 162 /**
 163  * mei_cl_irq_disconnect_rsp - send disconnection response message
 164  *
 165  * @cl: client
 166  * @cb: callback block.
 167  * @cmpl_list: complete list.
 168  *
 169  * returns 0, OK; otherwise, error.
 170  */
 171 static int mei_cl_irq_disconnect_rsp(struct mei_cl *cl, struct mei_cl_cb *cb,
 172                                      struct mei_cl_cb *cmpl_list)
 173 {
 174         struct mei_device *dev = cl->dev;
 175         u32 msg_slots;
 176         int slots;
 177         int ret;
 178
 179         slots = mei_hbuf_empty_slots(dev);
 180         msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_response));
 181
 182         if (slots < msg_slots)
 183                 return -EMSGSIZE;
 184
 185         ret = mei_hbm_cl_disconnect_rsp(dev, cl);
 186
 187         cl->state = MEI_FILE_DISCONNECTED;
 188         cl->status = 0;
 189         list_del(&cb->list);
 190         mei_io_cb_free(cb);
 191
 192         return ret;
 193 }
 194
 195
 196
 197 /**
 198  * mei_cl_irq_close - processes close related operation from
 199  *      interrupt thread context - send disconnect request
 200  *
 201  * @cl: client
 202  * @cb: callback block.
 203  * @cmpl_list: complete list.
 204  *
 205  * returns 0, OK; otherwise, error.
 206  */
 207 static int mei_cl_irq_close(struct mei_cl *cl, struct mei_cl_cb *cb,
 208                             struct mei_cl_cb *cmpl_list)
 209 {
 210         struct mei_device *dev = cl->dev;
 211         u32 msg_slots;
 212         int slots;
 213
 214         msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
 215         slots = mei_hbuf_empty_slots(dev);
 216
 217         if (slots < msg_slots)
 218                 return -EMSGSIZE;
 219
 220         if (mei_hbm_cl_disconnect_req(dev, cl)) {
 221                 cl->status = 0;
 222                 cb->buf_idx = 0;
 223                 list_move_tail(&cb->list, &cmpl_list->list);
 224                 return -EIO;
 225         }
 226
 227         cl->state = MEI_FILE_DISCONNECTING;
 228         cl->status = 0;
 229         cb->buf_idx = 0;
 230         list_move_tail(&cb->list, &dev->ctrl_rd_list.list);
 231         cl->timer_count = MEI_CONNECT_TIMEOUT;
 232
 233         return 0;
 234 }
 235
 236
 237 /**
 238  * mei_cl_irq_close - processes client read related operation from the
 239  *      interrupt thread context - request for flow control credits
 240  *
 241  * @cl: client
 242  * @cb: callback block.
 243  * @cmpl_list: complete list.
 244  *
 245  * returns 0, OK; otherwise, error.
 246  */
 247 static int mei_cl_irq_read(struct mei_cl *cl, struct mei_cl_cb *cb,
 248                            struct mei_cl_cb *cmpl_list)
 249 {
 250         struct mei_device *dev = cl->dev;
 251         u32 msg_slots;
 252         int slots;
 253         int ret;
 254
 255         msg_slots = mei_data2slots(sizeof(struct hbm_flow_control));
 256         slots = mei_hbuf_empty_slots(dev);
 257
 258         if (slots < msg_slots)
 259                 return -EMSGSIZE;
 260
 261         ret = mei_hbm_cl_flow_control_req(dev, cl);
 262         if (ret) {
 263                 cl->status = ret;
 264                 cb->buf_idx = 0;
 265                 list_move_tail(&cb->list, &cmpl_list->list);
 266                 return ret;
 267         }
 268
 269         list_move_tail(&cb->list, &dev->read_list.list);
 270
 271         return 0;
 272 }
 273
 274
 275 /**
 276  * mei_cl_irq_connect - send connect request in irq_thread context
 277  *
 278  * @cl: client
 279  * @cb: callback block.
 280  * @cmpl_list: complete list.
 281  *
 282  * returns 0, OK; otherwise, error.
 283  */
 284 static int mei_cl_irq_connect(struct mei_cl *cl, struct mei_cl_cb *cb,
 285                               struct mei_cl_cb *cmpl_list)
 286 {
 287         struct mei_device *dev = cl->dev;
 288         u32 msg_slots;
 289         int slots;
 290         int ret;
 291
 292         msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_request));
 293         slots = mei_hbuf_empty_slots(dev);
 294
 295         if (mei_cl_is_other_connecting(cl))
 296                 return 0;
 297
 298         if (slots < msg_slots)
 299                 return -EMSGSIZE;
 300
 301         cl->state = MEI_FILE_CONNECTING;
 302
 303         ret = mei_hbm_cl_connect_req(dev, cl);
 304         if (ret) {
 305                 cl->status = ret;
 306                 cb->buf_idx = 0;
 307                 list_del(&cb->list);
 308                 return ret;
 309         }
 310
 311         list_move_tail(&cb->list, &dev->ctrl_rd_list.list);
 312         cl->timer_count = MEI_CONNECT_TIMEOUT;
 313         return 0;
 314 }
 315
 316
 317 /**
 318  * mei_irq_read_handler - bottom half read routine after ISR to
 319  * handle the read processing.
 320  *
 321  * @dev: the device structure
 322  * @cmpl_list: An instance of our list structure
 323  * @slots: slots to read.
 324  *
 325  * returns 0 on success, <0 on failure.
 326  */
 327 int mei_irq_read_handler(struct mei_device *dev,
 328                 struct mei_cl_cb *cmpl_list, s32 *slots)
 329 {
 330         struct mei_msg_hdr *mei_hdr;
 331         struct mei_cl *cl;
 332         int ret;
 333
 334         if (!dev->rd_msg_hdr) {
 335                 dev->rd_msg_hdr = mei_read_hdr(dev);
 336                 (*slots)--;
 337                 dev_dbg(&dev->pdev->dev, "slots =%08x.\n", *slots);
 338         }
 339         mei_hdr = (struct mei_msg_hdr *) &dev->rd_msg_hdr;
 340         dev_dbg(&dev->pdev->dev, MEI_HDR_FMT, MEI_HDR_PRM(mei_hdr));
 341
 342         if (mei_hdr->reserved || !dev->rd_msg_hdr) {
 343                 dev_err(&dev->pdev->dev, "corrupted message header 0x%08X\n",
 344                                 dev->rd_msg_hdr);
 345                 ret = -EBADMSG;
 346                 goto end;
 347         }
 348
 349         if (mei_slots2data(*slots) < mei_hdr->length) {
 350                 dev_err(&dev->pdev->dev, "less data available than length=%08x.\n",
 351                                 *slots);
 352                 /* we can't read the message */
 353                 ret = -ENODATA;
 354                 goto end;
 355         }
 356
 357         /*  HBM message */
 358         if (mei_hdr->host_addr == 0 && mei_hdr->me_addr == 0) {
 359                 ret = mei_hbm_dispatch(dev, mei_hdr);
 360                 if (ret) {
 361                         dev_dbg(&dev->pdev->dev, "mei_hbm_dispatch failed ret = %d\n",
 362                                         ret);
 363                         goto end;
 364                 }
 365                 goto reset_slots;
 366         }
 367
 368         /* find recipient cl */
 369         list_for_each_entry(cl, &dev->file_list, link) {
 370                 if (mei_cl_hbm_equal(cl, mei_hdr)) {
 371                         cl_dbg(dev, cl, "got a message\n");
 372                         break;
 373                 }
 374         }
 375
 376         /* if no recipient cl was found we assume corrupted header */
 377         if (&cl->link == &dev->file_list) {
 378                 dev_err(&dev->pdev->dev, "no destination client found 0x%08X\n",
 379                                 dev->rd_msg_hdr);
 380                 ret = -EBADMSG;
 381                 goto end;
 382         }
 383
 384         if (mei_hdr->host_addr == dev->iamthif_cl.host_client_id &&
 385             MEI_FILE_CONNECTED == dev->iamthif_cl.state &&
 386             dev->iamthif_state == MEI_IAMTHIF_READING) {
 387
 388                 ret = mei_amthif_irq_read_msg(dev, mei_hdr, cmpl_list);
 389                 if (ret) {
 390                         dev_err(&dev->pdev->dev, "mei_amthif_irq_read_msg failed = %d\n",
 391                                         ret);
 392                         goto end;
 393                 }
 394         } else {
 395                 ret = mei_cl_irq_read_msg(dev, mei_hdr, cmpl_list);
 396                 if (ret) {
 397                         dev_err(&dev->pdev->dev, "mei_cl_irq_read_msg failed = %d\n",
 398                                         ret);
 399                         goto end;
 400                 }
 401         }
 402
 403 reset_slots:
 404         /* reset the number of slots and header */
 405         *slots = mei_count_full_read_slots(dev);
 406         dev->rd_msg_hdr = 0;
 407
 408         if (*slots == -EOVERFLOW) {
 409                 /* overflow - reset */
 410                 dev_err(&dev->pdev->dev, "resetting due to slots overflow.\n");
 411                 /* set the event since message has been read */
 412                 ret = -ERANGE;
 413                 goto end;
 414         }
 415 end:
 416         return ret;
 417 }
 418 EXPORT_SYMBOL_GPL(mei_irq_read_handler);
 419
 420
 421 /**
 422  * mei_irq_write_handler -  dispatch write requests
 423  *  after irq received
 424  *
 425  * @dev: the device structure
 426  * @cmpl_list: An instance of our list structure
 427  *
 428  * returns 0 on success, <0 on failure.
 429  */
 430 int mei_irq_write_handler(struct mei_device *dev, struct mei_cl_cb *cmpl_list)
 431 {
 432
 433         struct mei_cl *cl;
 434         struct mei_cl_cb *cb, *next;
 435         struct mei_cl_cb *list;
 436         s32 slots;
 437         int ret;
 438
 439
 440         if (!mei_hbuf_acquire(dev))
 441                 return 0;
 442
 443         slots = mei_hbuf_empty_slots(dev);
 444         if (slots <= 0)
 445                 return -EMSGSIZE;
 446
 447         /* complete all waiting for write CB */
 448         dev_dbg(&dev->pdev->dev, "complete all waiting for write cb.\n");
 449
 450         list = &dev->write_waiting_list;
 451         list_for_each_entry_safe(cb, next, &list->list, list) {
 452                 cl = cb->cl;
 453                 if (cl == NULL)
 454                         continue;
 455
 456                 cl->status = 0;
 457                 list_del(&cb->list);
 458                 if (MEI_WRITING == cl->writing_state &&
 459                     cb->fop_type == MEI_FOP_WRITE &&
 460                     cl != &dev->iamthif_cl) {
 461                         cl_dbg(dev, cl, "MEI WRITE COMPLETE\n");
 462                         cl->writing_state = MEI_WRITE_COMPLETE;
 463                         list_add_tail(&cb->list, &cmpl_list->list);
 464                 }
 465                 if (cl == &dev->iamthif_cl) {
 466                         cl_dbg(dev, cl, "check iamthif flow control.\n");
 467                         if (dev->iamthif_flow_control_pending) {
 468                                 ret = mei_amthif_irq_read(dev, &slots);
 469                                 if (ret)
 470                                         return ret;
 471                         }
 472                 }
 473         }
 474
 475         if (dev->wd_state == MEI_WD_STOPPING) {
 476                 dev->wd_state = MEI_WD_IDLE;
 477                 wake_up(&dev->wait_stop_wd);
 478         }
 479
 480         if (mei_cl_is_connected(&dev->wd_cl)) {
 481                 if (dev->wd_pending &&
 482                     mei_cl_flow_ctrl_creds(&dev->wd_cl) > 0) {
 483                         ret = mei_wd_send(dev);
 484                         if (ret)
 485                                 return ret;
 486                         dev->wd_pending = false;
 487                 }
 488         }
 489
 490         /* complete control write list CB */
 491         dev_dbg(&dev->pdev->dev, "complete control write list cb.\n");
 492         list_for_each_entry_safe(cb, next, &dev->ctrl_wr_list.list, list) {
 493                 cl = cb->cl;
 494                 if (!cl) {
 495                         list_del(&cb->list);
 496                         return -ENODEV;
 497                 }
 498                 switch (cb->fop_type) {
 499                 case MEI_FOP_CLOSE:
 500                         /* send disconnect message */
 501                         ret = mei_cl_irq_close(cl, cb, cmpl_list);
 502                         if (ret)
 503                                 return ret;
 504
 505                         break;
 506                 case MEI_FOP_READ:
 507                         /* send flow control message */
 508                         ret = mei_cl_irq_read(cl, cb, cmpl_list);
 509                         if (ret)
 510                                 return ret;
 511
 512                         break;
 513                 case MEI_FOP_CONNECT:
 514                         /* connect message */
 515                         ret = mei_cl_irq_connect(cl, cb, cmpl_list);
 516                         if (ret)
 517                                 return ret;
 518
 519                         break;
 520                 case MEI_FOP_DISCONNECT_RSP:
 521                         /* send disconnect resp */
 522                         ret = mei_cl_irq_disconnect_rsp(cl, cb, cmpl_list);
 523                         if (ret)
 524                                 return ret;
 525                         break;
 526                 default:
 527                         BUG();
 528                 }
 529
 530         }
 531         /* complete  write list CB */
 532         dev_dbg(&dev->pdev->dev, "complete write list cb.\n");
 533         list_for_each_entry_safe(cb, next, &dev->write_list.list, list) {
 534                 cl = cb->cl;
 535                 if (cl == NULL)
 536                         continue;
 537                 if (cl == &dev->iamthif_cl)
 538                         ret = mei_amthif_irq_write(cl, cb, cmpl_list);
 539                 else
 540                         ret = mei_cl_irq_write(cl, cb, cmpl_list);
 541                 if (ret)
 542                         return ret;
 543         }
 544         return 0;
 545 }
 546 EXPORT_SYMBOL_GPL(mei_irq_write_handler);
 547
 548
 549
 550 /**
 551  * mei_timer - timer function.
 552  *
 553  * @work: pointer to the work_struct structure
 554  *
 555  */
 556 void mei_timer(struct work_struct *work)
 557 {
 558         unsigned long timeout;
 559         struct mei_cl *cl;
 560         struct mei_cl_cb  *cb_pos = NULL;
 561         struct mei_cl_cb  *cb_next = NULL;
 562
 563         struct mei_device *dev = container_of(work,
 564                                         struct mei_device, timer_work.work);
 565
 566
 567         mutex_lock(&dev->device_lock);
 568
 569         /* Catch interrupt stalls during HBM init handshake */
 570         if (dev->dev_state == MEI_DEV_INIT_CLIENTS &&
 571             dev->hbm_state != MEI_HBM_IDLE) {
 572
 573                 if (dev->init_clients_timer) {
 574                         if (--dev->init_clients_timer == 0) {
 575                                 dev_err(&dev->pdev->dev, "timer: init clients timeout hbm_state = %d.\n",
 576                                         dev->hbm_state);
 577                                 mei_reset(dev);
 578                                 goto out;
 579                         }
 580                 }
 581         }
 582
 583         if (dev->dev_state != MEI_DEV_ENABLED)
 584                 goto out;
 585
 586         /*** connect/disconnect timeouts ***/
 587         list_for_each_entry(cl, &dev->file_list, link) {
 588                 if (cl->timer_count) {
 589                         if (--cl->timer_count == 0) {
 590                                 dev_err(&dev->pdev->dev, "timer: connect/disconnect timeout.\n");
 591                                 mei_reset(dev);
 592                                 goto out;
 593                         }
 594                 }
 595         }
 596
 597         if (!mei_cl_is_connected(&dev->iamthif_cl))
 598                 goto out;
 599
 600         if (dev->iamthif_stall_timer) {
 601                 if (--dev->iamthif_stall_timer == 0) {
 602                         dev_err(&dev->pdev->dev, "timer: amthif  hanged.\n");
 603                         mei_reset(dev);
 604                         dev->iamthif_msg_buf_size = 0;
 605                         dev->iamthif_msg_buf_index = 0;
 606                         dev->iamthif_canceled = false;
 607                         dev->iamthif_ioctl = true;
 608                         dev->iamthif_state = MEI_IAMTHIF_IDLE;
 609                         dev->iamthif_timer = 0;
 610
 611                         mei_io_cb_free(dev->iamthif_current_cb);
 612                         dev->iamthif_current_cb = NULL;
 613
 614                         dev->iamthif_file_object = NULL;
 615                         mei_amthif_run_next_cmd(dev);
 616                 }
 617         }
 618
 619         if (dev->iamthif_timer) {
 620
 621                 timeout = dev->iamthif_timer +
 622                         mei_secs_to_jiffies(MEI_IAMTHIF_READ_TIMER);
 623
 624                 dev_dbg(&dev->pdev->dev, "dev->iamthif_timer = %ld\n",
 625                                 dev->iamthif_timer);
 626                 dev_dbg(&dev->pdev->dev, "timeout = %ld\n", timeout);
 627                 dev_dbg(&dev->pdev->dev, "jiffies = %ld\n", jiffies);
 628                 if (time_after(jiffies, timeout)) {
 629                         /*
 630                          * User didn't read the AMTHI data on time (15sec)
 631                          * freeing AMTHI for other requests
 632                          */
 633
 634                         dev_dbg(&dev->pdev->dev, "freeing AMTHI for other requests\n");
 635
 636                         list_for_each_entry_safe(cb_pos, cb_next,
 637                                 &dev->amthif_rd_complete_list.list, list) {
 638
 639                                 cl = cb_pos->file_object->private_data;
 640
 641                                 /* Finding the AMTHI entry. */
 642                                 if (cl == &dev->iamthif_cl)
 643                                         list_del(&cb_pos->list);
 644                         }
 645                         mei_io_cb_free(dev->iamthif_current_cb);
 646                         dev->iamthif_current_cb = NULL;
 647
 648                         dev->iamthif_file_object->private_data = NULL;
 649                         dev->iamthif_file_object = NULL;
 650                         dev->iamthif_timer = 0;
 651                         mei_amthif_run_next_cmd(dev);
 652
 653                 }
 654         }
 655 out:
 656         if (dev->dev_state != MEI_DEV_DISABLED)
 657                 schedule_delayed_work(&dev->timer_work, 2 * HZ);
 658         mutex_unlock(&dev->device_lock);
 659 }
 660