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