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