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