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