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 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         mei_cl_set_disconnected(cl);
 188         mei_io_cb_free(cb);
 189         mei_me_cl_put(cl->me_cl);
 190         cl->me_cl = NULL;
 191
 192         return ret;
 193 }
 194
 195 /**
 196  * mei_cl_irq_read - processes client read related operation from the
 197  *      interrupt thread context - request for flow control credits
 198  *
 199  * @cl: client
 200  * @cb: callback block.
 201  * @cmpl_list: complete list.
 202  *
 203  * Return: 0, OK; otherwise, error.
 204  */
 205 static int mei_cl_irq_read(struct mei_cl *cl, struct mei_cl_cb *cb,
 206                            struct mei_cl_cb *cmpl_list)
 207 {
 208         struct mei_device *dev = cl->dev;
 209         u32 msg_slots;
 210         int slots;
 211         int ret;
 212
 213         msg_slots = mei_data2slots(sizeof(struct hbm_flow_control));
 214         slots = mei_hbuf_empty_slots(dev);
 215
 216         if (slots < msg_slots)
 217                 return -EMSGSIZE;
 218
 219         ret = mei_hbm_cl_flow_control_req(dev, cl);
 220         if (ret) {
 221                 cl->status = ret;
 222                 cb->buf_idx = 0;
 223                 list_move_tail(&cb->list, &cmpl_list->list);
 224                 return ret;
 225         }
 226
 227         list_move_tail(&cb->list, &cl->rd_pending);
 228
 229         return 0;
 230 }
 231
 232 /**
 233  * mei_irq_read_handler - bottom half read routine after ISR to
 234  * handle the read processing.
 235  *
 236  * @dev: the device structure
 237  * @cmpl_list: An instance of our list structure
 238  * @slots: slots to read.
 239  *
 240  * Return: 0 on success, <0 on failure.
 241  */
 242 int mei_irq_read_handler(struct mei_device *dev,
 243                 struct mei_cl_cb *cmpl_list, s32 *slots)
 244 {
 245         struct mei_msg_hdr *mei_hdr;
 246         struct mei_cl *cl;
 247         int ret;
 248
 249         if (!dev->rd_msg_hdr) {
 250                 dev->rd_msg_hdr = mei_read_hdr(dev);
 251                 (*slots)--;
 252                 dev_dbg(dev->dev, "slots =%08x.\n", *slots);
 253         }
 254         mei_hdr = (struct mei_msg_hdr *) &dev->rd_msg_hdr;
 255         dev_dbg(dev->dev, MEI_HDR_FMT, MEI_HDR_PRM(mei_hdr));
 256
 257         if (mei_hdr->reserved || !dev->rd_msg_hdr) {
 258                 dev_err(dev->dev, "corrupted message header 0x%08X\n",
 259                                 dev->rd_msg_hdr);
 260                 ret = -EBADMSG;
 261                 goto end;
 262         }
 263
 264         if (mei_slots2data(*slots) < mei_hdr->length) {
 265                 dev_err(dev->dev, "less data available than length=%08x.\n",
 266                                 *slots);
 267                 /* we can't read the message */
 268                 ret = -ENODATA;
 269                 goto end;
 270         }
 271
 272         /*  HBM message */
 273         if (mei_hdr->host_addr == 0 && mei_hdr->me_addr == 0) {
 274                 ret = mei_hbm_dispatch(dev, mei_hdr);
 275                 if (ret) {
 276                         dev_dbg(dev->dev, "mei_hbm_dispatch failed ret = %d\n",
 277                                         ret);
 278                         goto end;
 279                 }
 280                 goto reset_slots;
 281         }
 282
 283         /* find recipient cl */
 284         list_for_each_entry(cl, &dev->file_list, link) {
 285                 if (mei_cl_hbm_equal(cl, mei_hdr)) {
 286                         cl_dbg(dev, cl, "got a message\n");
 287                         break;
 288                 }
 289         }
 290
 291         /* if no recipient cl was found we assume corrupted header */
 292         if (&cl->link == &dev->file_list) {
 293                 dev_err(dev->dev, "no destination client found 0x%08X\n",
 294                                 dev->rd_msg_hdr);
 295                 ret = -EBADMSG;
 296                 goto end;
 297         }
 298
 299         if (cl == &dev->iamthif_cl) {
 300                 ret = mei_amthif_irq_read_msg(cl, mei_hdr, cmpl_list);
 301         } else {
 302                 ret = mei_cl_irq_read_msg(cl, mei_hdr, cmpl_list);
 303         }
 304
 305
 306 reset_slots:
 307         /* reset the number of slots and header */
 308         *slots = mei_count_full_read_slots(dev);
 309         dev->rd_msg_hdr = 0;
 310
 311         if (*slots == -EOVERFLOW) {
 312                 /* overflow - reset */
 313                 dev_err(dev->dev, "resetting due to slots overflow.\n");
 314                 /* set the event since message has been read */
 315                 ret = -ERANGE;
 316                 goto end;
 317         }
 318 end:
 319         return ret;
 320 }
 321 EXPORT_SYMBOL_GPL(mei_irq_read_handler);
 322
 323
 324 /**
 325  * mei_irq_write_handler -  dispatch write requests
 326  *  after irq received
 327  *
 328  * @dev: the device structure
 329  * @cmpl_list: An instance of our list structure
 330  *
 331  * Return: 0 on success, <0 on failure.
 332  */
 333 int mei_irq_write_handler(struct mei_device *dev, struct mei_cl_cb *cmpl_list)
 334 {
 335
 336         struct mei_cl *cl;
 337         struct mei_cl_cb *cb, *next;
 338         struct mei_cl_cb *list;
 339         s32 slots;
 340         int ret;
 341
 342
 343         if (!mei_hbuf_acquire(dev))
 344                 return 0;
 345
 346         slots = mei_hbuf_empty_slots(dev);
 347         if (slots <= 0)
 348                 return -EMSGSIZE;
 349
 350         /* complete all waiting for write CB */
 351         dev_dbg(dev->dev, "complete all waiting for write cb.\n");
 352
 353         list = &dev->write_waiting_list;
 354         list_for_each_entry_safe(cb, next, &list->list, list) {
 355                 cl = cb->cl;
 356
 357                 cl->status = 0;
 358                 cl_dbg(dev, cl, "MEI WRITE COMPLETE\n");
 359                 cl->writing_state = MEI_WRITE_COMPLETE;
 360                 list_move_tail(&cb->list, &cmpl_list->list);
 361         }
 362
 363         if (dev->wd_state == MEI_WD_STOPPING) {
 364                 dev->wd_state = MEI_WD_IDLE;
 365                 wake_up(&dev->wait_stop_wd);
 366         }
 367
 368         if (mei_cl_is_connected(&dev->wd_cl)) {
 369                 if (dev->wd_pending &&
 370                     mei_cl_flow_ctrl_creds(&dev->wd_cl) > 0) {
 371                         ret = mei_wd_send(dev);
 372                         if (ret)
 373                                 return ret;
 374                         dev->wd_pending = false;
 375                 }
 376         }
 377
 378         /* complete control write list CB */
 379         dev_dbg(dev->dev, "complete control write list cb.\n");
 380         list_for_each_entry_safe(cb, next, &dev->ctrl_wr_list.list, list) {
 381                 cl = cb->cl;
 382                 switch (cb->fop_type) {
 383                 case MEI_FOP_DISCONNECT:
 384                         /* send disconnect message */
 385                         ret = mei_cl_irq_disconnect(cl, cb, cmpl_list);
 386                         if (ret)
 387                                 return ret;
 388
 389                         break;
 390                 case MEI_FOP_READ:
 391                         /* send flow control message */
 392                         ret = mei_cl_irq_read(cl, cb, cmpl_list);
 393                         if (ret)
 394                                 return ret;
 395
 396                         break;
 397                 case MEI_FOP_CONNECT:
 398                         /* connect message */
 399                         ret = mei_cl_irq_connect(cl, cb, cmpl_list);
 400                         if (ret)
 401                                 return ret;
 402
 403                         break;
 404                 case MEI_FOP_DISCONNECT_RSP:
 405                         /* send disconnect resp */
 406                         ret = mei_cl_irq_disconnect_rsp(cl, cb, cmpl_list);
 407                         if (ret)
 408                                 return ret;
 409                         break;
 410
 411                 case MEI_FOP_NOTIFY_START:
 412                 case MEI_FOP_NOTIFY_STOP:
 413                         ret = mei_cl_irq_notify(cl, cb, cmpl_list);
 414                         if (ret)
 415                                 return ret;
 416                         break;
 417                 default:
 418                         BUG();
 419                 }
 420
 421         }
 422         /* complete  write list CB */
 423         dev_dbg(dev->dev, "complete write list cb.\n");
 424         list_for_each_entry_safe(cb, next, &dev->write_list.list, list) {
 425                 cl = cb->cl;
 426                 if (cl == &dev->iamthif_cl)
 427                         ret = mei_amthif_irq_write(cl, cb, cmpl_list);
 428                 else
 429                         ret = mei_cl_irq_write(cl, cb, cmpl_list);
 430                 if (ret)
 431                         return ret;
 432         }
 433         return 0;
 434 }
 435 EXPORT_SYMBOL_GPL(mei_irq_write_handler);
 436
 437
 438 /**
 439  * mei_connect_timeout  - connect/disconnect timeouts
 440  *
 441  * @cl: host client
 442  */
 443 static void mei_connect_timeout(struct mei_cl *cl)
 444 {
 445         struct mei_device *dev = cl->dev;
 446
 447         if (cl->state == MEI_FILE_CONNECTING) {
 448                 if (dev->hbm_f_dot_supported) {
 449                         cl->state = MEI_FILE_DISCONNECT_REQUIRED;
 450                         wake_up(&cl->wait);
 451                         return;
 452                 }
 453         }
 454         mei_reset(dev);
 455 }
 456
 457 /**
 458  * mei_timer - timer function.
 459  *
 460  * @work: pointer to the work_struct structure
 461  *
 462  */
 463 void mei_timer(struct work_struct *work)
 464 {
 465         unsigned long timeout;
 466         struct mei_cl *cl;
 467
 468         struct mei_device *dev = container_of(work,
 469                                         struct mei_device, timer_work.work);
 470
 471
 472         mutex_lock(&dev->device_lock);
 473
 474         /* Catch interrupt stalls during HBM init handshake */
 475         if (dev->dev_state == MEI_DEV_INIT_CLIENTS &&
 476             dev->hbm_state != MEI_HBM_IDLE) {
 477
 478                 if (dev->init_clients_timer) {
 479                         if (--dev->init_clients_timer == 0) {
 480                                 dev_err(dev->dev, "timer: init clients timeout hbm_state = %d.\n",
 481                                         dev->hbm_state);
 482                                 mei_reset(dev);
 483                                 goto out;
 484                         }
 485                 }
 486         }
 487
 488         if (dev->dev_state != MEI_DEV_ENABLED)
 489                 goto out;
 490
 491         /*** connect/disconnect timeouts ***/
 492         list_for_each_entry(cl, &dev->file_list, link) {
 493                 if (cl->timer_count) {
 494                         if (--cl->timer_count == 0) {
 495                                 dev_err(dev->dev, "timer: connect/disconnect timeout.\n");
 496                                 mei_connect_timeout(cl);
 497                                 goto out;
 498                         }
 499                 }
 500         }
 501
 502         if (!mei_cl_is_connected(&dev->iamthif_cl))
 503                 goto out;
 504
 505         if (dev->iamthif_stall_timer) {
 506                 if (--dev->iamthif_stall_timer == 0) {
 507                         dev_err(dev->dev, "timer: amthif  hanged.\n");
 508                         mei_reset(dev);
 509                         dev->iamthif_canceled = false;
 510                         dev->iamthif_state = MEI_IAMTHIF_IDLE;
 511                         dev->iamthif_timer = 0;
 512
 513                         mei_io_cb_free(dev->iamthif_current_cb);
 514                         dev->iamthif_current_cb = NULL;
 515
 516                         dev->iamthif_file_object = NULL;
 517                         mei_amthif_run_next_cmd(dev);
 518                 }
 519         }
 520
 521         if (dev->iamthif_timer) {
 522
 523                 timeout = dev->iamthif_timer +
 524                         mei_secs_to_jiffies(MEI_IAMTHIF_READ_TIMER);
 525
 526                 dev_dbg(dev->dev, "dev->iamthif_timer = %ld\n",
 527                                 dev->iamthif_timer);
 528                 dev_dbg(dev->dev, "timeout = %ld\n", timeout);
 529                 dev_dbg(dev->dev, "jiffies = %ld\n", jiffies);
 530                 if (time_after(jiffies, timeout)) {
 531                         /*
 532                          * User didn't read the AMTHI data on time (15sec)
 533                          * freeing AMTHI for other requests
 534                          */
 535
 536                         dev_dbg(dev->dev, "freeing AMTHI for other requests\n");
 537
 538                         mei_io_list_flush(&dev->amthif_rd_complete_list,
 539                                 &dev->iamthif_cl);
 540                         mei_io_cb_free(dev->iamthif_current_cb);
 541                         dev->iamthif_current_cb = NULL;
 542
 543                         dev->iamthif_file_object->private_data = NULL;
 544                         dev->iamthif_file_object = NULL;
 545                         dev->iamthif_timer = 0;
 546                         mei_amthif_run_next_cmd(dev);
 547
 548                 }
 549         }
 550 out:
 551         if (dev->dev_state != MEI_DEV_DISABLED)
 552                 schedule_delayed_work(&dev->timer_work, 2 * HZ);
 553         mutex_unlock(&dev->device_lock);
 554 }