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