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 #include <linux/pm_runtime.h>
  25
  26 #include <linux/mei.h>
  27
  28 #include "mei_dev.h"
  29 #include "hbm.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_init(&cb->list);
  48
  49                 dev_dbg(dev->dev, "completing call back.\n");
  50                 if (cl == &dev->iamthif_cl)
  51                         mei_amthif_complete(dev, cb);
  52                 else
  53                         mei_cl_complete(cl, cb);
  54         }
  55 }
  56 EXPORT_SYMBOL_GPL(mei_irq_compl_handler);
  57
  58 /**
  59  * mei_cl_hbm_equal - check if hbm is addressed to the client
  60  *
  61  * @cl: host client
  62  * @mei_hdr: header of mei client message
  63  *
  64  * Return: true if matches, false otherwise
  65  */
  66 static inline int mei_cl_hbm_equal(struct mei_cl *cl,
  67                         struct mei_msg_hdr *mei_hdr)
  68 {
  69         return  mei_cl_host_addr(cl) == mei_hdr->host_addr &&
  70                 mei_cl_me_id(cl) == mei_hdr->me_addr;
  71 }
  72
  73 /**
  74  * mei_irq_discard_msg  - discard received message
  75  *
  76  * @dev: mei device
  77  * @hdr: message header
  78  */
  79 static inline
  80 void mei_irq_discard_msg(struct mei_device *dev, struct mei_msg_hdr *hdr)
  81 {
  82         /*
  83          * no need to check for size as it is guarantied
  84          * that length fits into rd_msg_buf
  85          */
  86         mei_read_slots(dev, dev->rd_msg_buf, hdr->length);
  87         dev_dbg(dev->dev, "discarding message " MEI_HDR_FMT "\n",
  88                 MEI_HDR_PRM(hdr));
  89 }
  90
  91 /**
  92  * mei_cl_irq_read_msg - process client message
  93  *
  94  * @cl: reading client
  95  * @mei_hdr: header of mei client message
  96  * @complete_list: completion list
  97  *
  98  * Return: always 0
  99  */
 100 int mei_cl_irq_read_msg(struct mei_cl *cl,
 101                        struct mei_msg_hdr *mei_hdr,
 102                        struct mei_cl_cb *complete_list)
 103 {
 104         struct mei_device *dev = cl->dev;
 105         struct mei_cl_cb *cb;
 106         unsigned char *buffer = NULL;
 107
 108         cb = list_first_entry_or_null(&cl->rd_pending, struct mei_cl_cb, list);
 109         if (!cb) {
 110                 cl_err(dev, cl, "pending read cb not found\n");
 111                 goto out;
 112         }
 113
 114         if (!mei_cl_is_connected(cl)) {
 115                 cl_dbg(dev, cl, "not connected\n");
 116                 cb->status = -ENODEV;
 117                 goto out;
 118         }
 119
 120         if (cb->buf.size == 0 || cb->buf.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->buf.size < mei_hdr->length + cb->buf_idx) {
 128                 cl_dbg(dev, cl, "message overflow. size %d len %d idx %ld\n",
 129                         cb->buf.size, mei_hdr->length, cb->buf_idx);
 130                 buffer = krealloc(cb->buf.data, mei_hdr->length + cb->buf_idx,
 131                                   GFP_KERNEL);
 132
 133                 if (!buffer) {
 134                         cb->status = -ENOMEM;
 135                         list_move_tail(&cb->list, &complete_list->list);
 136                         goto out;
 137                 }
 138                 cb->buf.data = buffer;
 139                 cb->buf.size = mei_hdr->length + cb->buf_idx;
 140         }
 141
 142         buffer = cb->buf.data + cb->buf_idx;
 143         mei_read_slots(dev, buffer, mei_hdr->length);
 144
 145         cb->buf_idx += mei_hdr->length;
 146
 147         if (mei_hdr->msg_complete) {
 148                 cb->read_time = jiffies;
 149                 cl_dbg(dev, cl, "completed read length = %lu\n", cb->buf_idx);
 150                 list_move_tail(&cb->list, &complete_list->list);
 151         } else {
 152                 pm_runtime_mark_last_busy(dev->dev);
 153                 pm_request_autosuspend(dev->dev);
 154         }
 155
 156 out:
 157         if (!buffer)
 158                 mei_irq_discard_msg(dev, mei_hdr);
 159
 160         return 0;
 161 }
 162
 163 /**
 164  * mei_cl_irq_disconnect_rsp - send disconnection response message
 165  *
 166  * @cl: client
 167  * @cb: callback block.
 168  * @cmpl_list: complete list.
 169  *
 170  * Return: 0, OK; otherwise, error.
 171  */
 172 static int mei_cl_irq_disconnect_rsp(struct mei_cl *cl, struct mei_cl_cb *cb,
 173                                      struct mei_cl_cb *cmpl_list)
 174 {
 175         struct mei_device *dev = cl->dev;
 176         u32 msg_slots;
 177         int slots;
 178         int ret;
 179
 180         slots = mei_hbuf_empty_slots(dev);
 181         msg_slots = mei_data2slots(sizeof(struct hbm_client_connect_response));
 182
 183         if (slots < msg_slots)
 184                 return -EMSGSIZE;
 185
 186         ret = mei_hbm_cl_disconnect_rsp(dev, cl);
 187         list_move_tail(&cb->list, &cmpl_list->list);
 188
 189         return ret;
 190 }
 191
 192 /**
 193  * mei_cl_irq_read - processes client read related operation from the
 194  *      interrupt thread context - request for flow control credits
 195  *
 196  * @cl: client
 197  * @cb: callback block.
 198  * @cmpl_list: complete list.
 199  *
 200  * Return: 0, OK; otherwise, error.
 201  */
 202 static int mei_cl_irq_read(struct mei_cl *cl, struct mei_cl_cb *cb,
 203                            struct mei_cl_cb *cmpl_list)
 204 {
 205         struct mei_device *dev = cl->dev;
 206         u32 msg_slots;
 207         int slots;
 208         int ret;
 209
 210         msg_slots = mei_data2slots(sizeof(struct hbm_flow_control));
 211         slots = mei_hbuf_empty_slots(dev);
 212
 213         if (slots < msg_slots)
 214                 return -EMSGSIZE;
 215
 216         ret = mei_hbm_cl_flow_control_req(dev, cl);
 217         if (ret) {
 218                 cl->status = ret;
 219                 cb->buf_idx = 0;
 220                 list_move_tail(&cb->list, &cmpl_list->list);
 221                 return ret;
 222         }
 223
 224         list_move_tail(&cb->list, &cl->rd_pending);
 225
 226         return 0;
 227 }
 228
 229 /**
 230  * mei_irq_read_handler - bottom half read routine after ISR to
 231  * handle the read processing.
 232  *
 233  * @dev: the device structure
 234  * @cmpl_list: An instance of our list structure
 235  * @slots: slots to read.
 236  *
 237  * Return: 0 on success, <0 on failure.
 238  */
 239 int mei_irq_read_handler(struct mei_device *dev,
 240                 struct mei_cl_cb *cmpl_list, s32 *slots)
 241 {
 242         struct mei_msg_hdr *mei_hdr;
 243         struct mei_cl *cl;
 244         int ret;
 245
 246         if (!dev->rd_msg_hdr) {
 247                 dev->rd_msg_hdr = mei_read_hdr(dev);
 248                 (*slots)--;
 249                 dev_dbg(dev->dev, "slots =%08x.\n", *slots);
 250         }
 251         mei_hdr = (struct mei_msg_hdr *) &dev->rd_msg_hdr;
 252         dev_dbg(dev->dev, MEI_HDR_FMT, MEI_HDR_PRM(mei_hdr));
 253
 254         if (mei_hdr->reserved || !dev->rd_msg_hdr) {
 255                 dev_err(dev->dev, "corrupted message header 0x%08X\n",
 256                                 dev->rd_msg_hdr);
 257                 ret = -EBADMSG;
 258                 goto end;
 259         }
 260
 261         if (mei_slots2data(*slots) < mei_hdr->length) {
 262                 dev_err(dev->dev, "less data available than length=%08x.\n",
 263                                 *slots);
 264                 /* we can't read the message */
 265                 ret = -ENODATA;
 266                 goto end;
 267         }
 268
 269         /*  HBM message */
 270         if (mei_hdr->host_addr == 0 && mei_hdr->me_addr == 0) {
 271                 ret = mei_hbm_dispatch(dev, mei_hdr);
 272                 if (ret) {
 273                         dev_dbg(dev->dev, "mei_hbm_dispatch failed ret = %d\n",
 274                                         ret);
 275                         goto end;
 276                 }
 277                 goto reset_slots;
 278         }
 279
 280         /* find recipient cl */
 281         list_for_each_entry(cl, &dev->file_list, link) {
 282                 if (mei_cl_hbm_equal(cl, mei_hdr)) {
 283                         cl_dbg(dev, cl, "got a message\n");
 284                         break;
 285                 }
 286         }
 287
 288         /* if no recipient cl was found we assume corrupted header */
 289         if (&cl->link == &dev->file_list) {
 290                 dev_err(dev->dev, "no destination client found 0x%08X\n",
 291                                 dev->rd_msg_hdr);
 292                 ret = -EBADMSG;
 293                 goto end;
 294         }
 295
 296         if (cl == &dev->iamthif_cl) {
 297                 ret = mei_amthif_irq_read_msg(cl, mei_hdr, cmpl_list);
 298         } else {
 299                 ret = mei_cl_irq_read_msg(cl, mei_hdr, cmpl_list);
 300         }
 301
 302
 303 reset_slots:
 304         /* reset the number of slots and header */
 305         *slots = mei_count_full_read_slots(dev);
 306         dev->rd_msg_hdr = 0;
 307
 308         if (*slots == -EOVERFLOW) {
 309                 /* overflow - reset */
 310                 dev_err(dev->dev, "resetting due to slots overflow.\n");
 311                 /* set the event since message has been read */
 312                 ret = -ERANGE;
 313                 goto end;
 314         }
 315 end:
 316         return ret;
 317 }
 318 EXPORT_SYMBOL_GPL(mei_irq_read_handler);
 319
 320
 321 /**
 322  * mei_irq_write_handler -  dispatch write requests
 323  *  after irq received
 324  *
 325  * @dev: the device structure
 326  * @cmpl_list: An instance of our list structure
 327  *
 328  * Return: 0 on success, <0 on failure.
 329  */
 330 int mei_irq_write_handler(struct mei_device *dev, struct mei_cl_cb *cmpl_list)
 331 {
 332
 333         struct mei_cl *cl;
 334         struct mei_cl_cb *cb, *next;
 335         struct mei_cl_cb *list;
 336         s32 slots;
 337         int ret;
 338
 339
 340         if (!mei_hbuf_acquire(dev))
 341                 return 0;
 342
 343         slots = mei_hbuf_empty_slots(dev);
 344         if (slots <= 0)
 345                 return -EMSGSIZE;
 346
 347         /* complete all waiting for write CB */
 348         dev_dbg(dev->dev, "complete all waiting for write cb.\n");
 349
 350         list = &dev->write_waiting_list;
 351         list_for_each_entry_safe(cb, next, &list->list, list) {
 352                 cl = cb->cl;
 353
 354                 cl->status = 0;
 355                 cl_dbg(dev, cl, "MEI WRITE COMPLETE\n");
 356                 cl->writing_state = MEI_WRITE_COMPLETE;
 357                 list_move_tail(&cb->list, &cmpl_list->list);
 358         }
 359
 360         if (dev->wd_state == MEI_WD_STOPPING) {
 361                 dev->wd_state = MEI_WD_IDLE;
 362                 wake_up(&dev->wait_stop_wd);
 363         }
 364
 365         if (mei_cl_is_connected(&dev->wd_cl)) {
 366                 if (dev->wd_pending &&
 367                     mei_cl_flow_ctrl_creds(&dev->wd_cl) > 0) {
 368                         ret = mei_wd_send(dev);
 369                         if (ret)
 370                                 return ret;
 371                         dev->wd_pending = false;
 372                 }
 373         }
 374
 375         /* complete control write list CB */
 376         dev_dbg(dev->dev, "complete control write list cb.\n");
 377         list_for_each_entry_safe(cb, next, &dev->ctrl_wr_list.list, list) {
 378                 cl = cb->cl;
 379                 switch (cb->fop_type) {
 380                 case MEI_FOP_DISCONNECT:
 381                         /* send disconnect message */
 382                         ret = mei_cl_irq_disconnect(cl, cb, cmpl_list);
 383                         if (ret)
 384                                 return ret;
 385
 386                         break;
 387                 case MEI_FOP_READ:
 388                         /* send flow control message */
 389                         ret = mei_cl_irq_read(cl, cb, cmpl_list);
 390                         if (ret)
 391                                 return ret;
 392
 393                         break;
 394                 case MEI_FOP_CONNECT:
 395                         /* connect message */
 396                         ret = mei_cl_irq_connect(cl, cb, cmpl_list);
 397                         if (ret)
 398                                 return ret;
 399
 400                         break;
 401                 case MEI_FOP_DISCONNECT_RSP:
 402                         /* send disconnect resp */
 403                         ret = mei_cl_irq_disconnect_rsp(cl, cb, cmpl_list);
 404                         if (ret)
 405                                 return ret;
 406                         break;
 407
 408                 case MEI_FOP_NOTIFY_START:
 409                 case MEI_FOP_NOTIFY_STOP:
 410                         ret = mei_cl_irq_notify(cl, cb, cmpl_list);
 411                         if (ret)
 412                                 return ret;
 413                         break;
 414                 default:
 415                         BUG();
 416                 }
 417
 418         }
 419         /* complete  write list CB */
 420         dev_dbg(dev->dev, "complete write list cb.\n");
 421         list_for_each_entry_safe(cb, next, &dev->write_list.list, list) {
 422                 cl = cb->cl;
 423                 if (cl == &dev->iamthif_cl)
 424                         ret = mei_amthif_irq_write(cl, cb, cmpl_list);
 425                 else
 426                         ret = mei_cl_irq_write(cl, cb, cmpl_list);
 427                 if (ret)
 428                         return ret;
 429         }
 430         return 0;
 431 }
 432 EXPORT_SYMBOL_GPL(mei_irq_write_handler);
 433
 434
 435 /**
 436  * mei_connect_timeout  - connect/disconnect timeouts
 437  *
 438  * @cl: host client
 439  */
 440 static void mei_connect_timeout(struct mei_cl *cl)
 441 {
 442         struct mei_device *dev = cl->dev;
 443
 444         if (cl->state == MEI_FILE_CONNECTING) {
 445                 if (dev->hbm_f_dot_supported) {
 446                         cl->state = MEI_FILE_DISCONNECT_REQUIRED;
 447                         wake_up(&cl->wait);
 448                         return;
 449                 }
 450         }
 451         mei_reset(dev);
 452 }
 453
 454 /**
 455  * mei_timer - timer function.
 456  *
 457  * @work: pointer to the work_struct structure
 458  *
 459  */
 460 void mei_timer(struct work_struct *work)
 461 {
 462         unsigned long timeout;
 463         struct mei_cl *cl;
 464
 465         struct mei_device *dev = container_of(work,
 466                                         struct mei_device, timer_work.work);
 467
 468
 469         mutex_lock(&dev->device_lock);
 470
 471         /* Catch interrupt stalls during HBM init handshake */
 472         if (dev->dev_state == MEI_DEV_INIT_CLIENTS &&
 473             dev->hbm_state != MEI_HBM_IDLE) {
 474
 475                 if (dev->init_clients_timer) {
 476                         if (--dev->init_clients_timer == 0) {
 477                                 dev_err(dev->dev, "timer: init clients timeout hbm_state = %d.\n",
 478                                         dev->hbm_state);
 479                                 mei_reset(dev);
 480                                 goto out;
 481                         }
 482                 }
 483         }
 484
 485         if (dev->dev_state != MEI_DEV_ENABLED)
 486                 goto out;
 487
 488         /*** connect/disconnect timeouts ***/
 489         list_for_each_entry(cl, &dev->file_list, link) {
 490                 if (cl->timer_count) {
 491                         if (--cl->timer_count == 0) {
 492                                 dev_err(dev->dev, "timer: connect/disconnect timeout.\n");
 493                                 mei_connect_timeout(cl);
 494                                 goto out;
 495                         }
 496                 }
 497         }
 498
 499         if (!mei_cl_is_connected(&dev->iamthif_cl))
 500                 goto out;
 501
 502         if (dev->iamthif_stall_timer) {
 503                 if (--dev->iamthif_stall_timer == 0) {
 504                         dev_err(dev->dev, "timer: amthif  hanged.\n");
 505                         mei_reset(dev);
 506                         dev->iamthif_canceled = false;
 507                         dev->iamthif_state = MEI_IAMTHIF_IDLE;
 508                         dev->iamthif_timer = 0;
 509
 510                         mei_io_cb_free(dev->iamthif_current_cb);
 511                         dev->iamthif_current_cb = NULL;
 512
 513                         dev->iamthif_file_object = NULL;
 514                         mei_amthif_run_next_cmd(dev);
 515                 }
 516         }
 517
 518         if (dev->iamthif_timer) {
 519
 520                 timeout = dev->iamthif_timer +
 521                         mei_secs_to_jiffies(MEI_IAMTHIF_READ_TIMER);
 522
 523                 dev_dbg(dev->dev, "dev->iamthif_timer = %ld\n",
 524                                 dev->iamthif_timer);
 525                 dev_dbg(dev->dev, "timeout = %ld\n", timeout);
 526                 dev_dbg(dev->dev, "jiffies = %ld\n", jiffies);
 527                 if (time_after(jiffies, timeout)) {
 528                         /*
 529                          * User didn't read the AMTHI data on time (15sec)
 530                          * freeing AMTHI for other requests
 531                          */
 532
 533                         dev_dbg(dev->dev, "freeing AMTHI for other requests\n");
 534
 535                         mei_io_list_flush(&dev->amthif_rd_complete_list,
 536                                 &dev->iamthif_cl);
 537                         mei_io_cb_free(dev->iamthif_current_cb);
 538                         dev->iamthif_current_cb = NULL;
 539
 540                         dev->iamthif_file_object->private_data = NULL;
 541                         dev->iamthif_file_object = NULL;
 542                         dev->iamthif_timer = 0;
 543                         mei_amthif_run_next_cmd(dev);
 544
 545                 }
 546         }
 547 out:
 548         if (dev->dev_state != MEI_DEV_DISABLED)
 549                 schedule_delayed_work(&dev->timer_work, 2 * HZ);
 550         mutex_unlock(&dev->device_lock);
 551 }