1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (c) 2003-2018, Intel Corporation. All rights reserved. 4 * Intel Management Engine Interface (Intel MEI) Linux driver 5 */ 6 7 #include <linux/export.h> 8 #include <linux/kthread.h> 9 #include <linux/interrupt.h> 10 #include <linux/fs.h> 11 #include <linux/jiffies.h> 12 #include <linux/slab.h> 13 #include <linux/pm_runtime.h> 14 15 #include <linux/mei.h> 16 17 #include "mei_dev.h" 18 #include "hbm.h" 19 #include "client.h" 20 21 22 /** 23 * mei_irq_compl_handler - dispatch complete handlers 24 * for the completed callbacks 25 * 26 * @dev: mei device 27 * @cmpl_list: list of completed cbs 28 */ 29 void mei_irq_compl_handler(struct mei_device *dev, struct list_head *cmpl_list) 30 { 31 struct mei_cl_cb *cb, *next; 32 struct mei_cl *cl; 33 34 list_for_each_entry_safe(cb, next, cmpl_list, list) { 35 cl = cb->cl; 36 list_del_init(&cb->list); 37 38 dev_dbg(dev->dev, "completing call back.\n"); 39 mei_cl_complete(cl, cb); 40 } 41 } 42 EXPORT_SYMBOL_GPL(mei_irq_compl_handler); 43 44 /** 45 * mei_cl_hbm_equal - check if hbm is addressed to the client 46 * 47 * @cl: host client 48 * @mei_hdr: header of mei client message 49 * 50 * Return: true if matches, false otherwise 51 */ 52 static inline int mei_cl_hbm_equal(struct mei_cl *cl, 53 struct mei_msg_hdr *mei_hdr) 54 { 55 return mei_cl_host_addr(cl) == mei_hdr->host_addr && 56 mei_cl_me_id(cl) == mei_hdr->me_addr; 57 } 58 59 /** 60 * mei_irq_discard_msg - discard received message 61 * 62 * @dev: mei device 63 * @hdr: message header 64 * @discard_len: the length of the message to discard (excluding header) 65 */ 66 static void mei_irq_discard_msg(struct mei_device *dev, struct mei_msg_hdr *hdr, 67 size_t discard_len) 68 { 69 if (hdr->dma_ring) { 70 mei_dma_ring_read(dev, NULL, 71 hdr->extension[dev->rd_msg_hdr_count - 2]); 72 discard_len = 0; 73 } 74 /* 75 * no need to check for size as it is guarantied 76 * that length fits into rd_msg_buf 77 */ 78 mei_read_slots(dev, dev->rd_msg_buf, discard_len); 79 dev_dbg(dev->dev, "discarding message " MEI_HDR_FMT "\n", 80 MEI_HDR_PRM(hdr)); 81 } 82 83 /** 84 * mei_cl_irq_read_msg - process client message 85 * 86 * @cl: reading client 87 * @mei_hdr: header of mei client message 88 * @meta: extend meta header 89 * @cmpl_list: completion list 90 * 91 * Return: always 0 92 */ 93 static int mei_cl_irq_read_msg(struct mei_cl *cl, 94 struct mei_msg_hdr *mei_hdr, 95 struct mei_ext_meta_hdr *meta, 96 struct list_head *cmpl_list) 97 { 98 struct mei_device *dev = cl->dev; 99 struct mei_cl_cb *cb; 100 101 struct mei_ext_hdr_vtag *vtag_hdr = NULL; 102 struct mei_ext_hdr_gsc_f2h *gsc_f2h = NULL; 103 104 size_t buf_sz; 105 u32 length; 106 u32 ext_len; 107 108 length = mei_hdr->length; 109 ext_len = 0; 110 if (mei_hdr->extended) { 111 ext_len = sizeof(*meta) + mei_slots2data(meta->size); 112 length -= ext_len; 113 } 114 115 cb = list_first_entry_or_null(&cl->rd_pending, struct mei_cl_cb, list); 116 if (!cb) { 117 if (!mei_cl_is_fixed_address(cl)) { 118 cl_err(dev, cl, "pending read cb not found\n"); 119 goto discard; 120 } 121 cb = mei_cl_alloc_cb(cl, mei_cl_mtu(cl), MEI_FOP_READ, cl->fp); 122 if (!cb) 123 goto discard; 124 list_add_tail(&cb->list, &cl->rd_pending); 125 } 126 127 if (mei_hdr->extended) { 128 struct mei_ext_hdr *ext = mei_ext_begin(meta); 129 do { 130 switch (ext->type) { 131 case MEI_EXT_HDR_VTAG: 132 vtag_hdr = (struct mei_ext_hdr_vtag *)ext; 133 break; 134 case MEI_EXT_HDR_GSC: 135 gsc_f2h = (struct mei_ext_hdr_gsc_f2h *)ext; 136 cb->ext_hdr = kzalloc(sizeof(*gsc_f2h), GFP_KERNEL); 137 if (!cb->ext_hdr) { 138 cb->status = -ENOMEM; 139 goto discard; 140 } 141 break; 142 case MEI_EXT_HDR_NONE: 143 fallthrough; 144 default: 145 cl_err(dev, cl, "unknown extended header\n"); 146 cb->status = -EPROTO; 147 break; 148 } 149 150 ext = mei_ext_next(ext); 151 } while (!mei_ext_last(meta, ext)); 152 153 if (!vtag_hdr && !gsc_f2h) { 154 cl_dbg(dev, cl, "no vtag or gsc found in extended header.\n"); 155 cb->status = -EPROTO; 156 goto discard; 157 } 158 } 159 160 if (vtag_hdr) { 161 cl_dbg(dev, cl, "vtag: %d\n", vtag_hdr->vtag); 162 if (cb->vtag && cb->vtag != vtag_hdr->vtag) { 163 cl_err(dev, cl, "mismatched tag: %d != %d\n", 164 cb->vtag, vtag_hdr->vtag); 165 cb->status = -EPROTO; 166 goto discard; 167 } 168 cb->vtag = vtag_hdr->vtag; 169 } 170 171 if (gsc_f2h) { 172 u32 ext_hdr_len = mei_ext_hdr_len(&gsc_f2h->hdr); 173 174 if (!dev->hbm_f_gsc_supported) { 175 cl_err(dev, cl, "gsc extended header is not supported\n"); 176 cb->status = -EPROTO; 177 goto discard; 178 } 179 180 if (length) { 181 cl_err(dev, cl, "no data allowed in cb with gsc\n"); 182 cb->status = -EPROTO; 183 goto discard; 184 } 185 if (ext_hdr_len > sizeof(*gsc_f2h)) { 186 cl_err(dev, cl, "gsc extended header is too big %u\n", ext_hdr_len); 187 cb->status = -EPROTO; 188 goto discard; 189 } 190 memcpy(cb->ext_hdr, gsc_f2h, ext_hdr_len); 191 } 192 193 if (!mei_cl_is_connected(cl)) { 194 cl_dbg(dev, cl, "not connected\n"); 195 cb->status = -ENODEV; 196 goto discard; 197 } 198 199 if (mei_hdr->dma_ring) 200 length = mei_hdr->extension[mei_data2slots(ext_len)]; 201 202 buf_sz = length + cb->buf_idx; 203 /* catch for integer overflow */ 204 if (buf_sz < cb->buf_idx) { 205 cl_err(dev, cl, "message is too big len %d idx %zu\n", 206 length, cb->buf_idx); 207 cb->status = -EMSGSIZE; 208 goto discard; 209 } 210 211 if (cb->buf.size < buf_sz) { 212 cl_dbg(dev, cl, "message overflow. size %zu len %d idx %zu\n", 213 cb->buf.size, length, cb->buf_idx); 214 cb->status = -EMSGSIZE; 215 goto discard; 216 } 217 218 if (mei_hdr->dma_ring) { 219 mei_dma_ring_read(dev, cb->buf.data + cb->buf_idx, length); 220 /* for DMA read 0 length to generate interrupt to the device */ 221 mei_read_slots(dev, cb->buf.data + cb->buf_idx, 0); 222 } else { 223 mei_read_slots(dev, cb->buf.data + cb->buf_idx, length); 224 } 225 226 cb->buf_idx += length; 227 228 if (mei_hdr->msg_complete) { 229 cl_dbg(dev, cl, "completed read length = %zu\n", cb->buf_idx); 230 list_move_tail(&cb->list, cmpl_list); 231 } else { 232 pm_runtime_mark_last_busy(dev->dev); 233 pm_request_autosuspend(dev->dev); 234 } 235 236 return 0; 237 238 discard: 239 if (cb) 240 list_move_tail(&cb->list, cmpl_list); 241 mei_irq_discard_msg(dev, mei_hdr, length); 242 return 0; 243 } 244 245 /** 246 * mei_cl_irq_disconnect_rsp - send disconnection response message 247 * 248 * @cl: client 249 * @cb: callback block. 250 * @cmpl_list: complete list. 251 * 252 * Return: 0, OK; otherwise, error. 253 */ 254 static int mei_cl_irq_disconnect_rsp(struct mei_cl *cl, struct mei_cl_cb *cb, 255 struct list_head *cmpl_list) 256 { 257 struct mei_device *dev = cl->dev; 258 u32 msg_slots; 259 int slots; 260 int ret; 261 262 msg_slots = mei_hbm2slots(sizeof(struct hbm_client_connect_response)); 263 slots = mei_hbuf_empty_slots(dev); 264 if (slots < 0) 265 return -EOVERFLOW; 266 267 if ((u32)slots < msg_slots) 268 return -EMSGSIZE; 269 270 ret = mei_hbm_cl_disconnect_rsp(dev, cl); 271 list_move_tail(&cb->list, cmpl_list); 272 273 return ret; 274 } 275 276 /** 277 * mei_cl_irq_read - processes client read related operation from the 278 * interrupt thread context - request for flow control credits 279 * 280 * @cl: client 281 * @cb: callback block. 282 * @cmpl_list: complete list. 283 * 284 * Return: 0, OK; otherwise, error. 285 */ 286 static int mei_cl_irq_read(struct mei_cl *cl, struct mei_cl_cb *cb, 287 struct list_head *cmpl_list) 288 { 289 struct mei_device *dev = cl->dev; 290 u32 msg_slots; 291 int slots; 292 int ret; 293 294 if (!list_empty(&cl->rd_pending)) 295 return 0; 296 297 msg_slots = mei_hbm2slots(sizeof(struct hbm_flow_control)); 298 slots = mei_hbuf_empty_slots(dev); 299 if (slots < 0) 300 return -EOVERFLOW; 301 302 if ((u32)slots < msg_slots) 303 return -EMSGSIZE; 304 305 ret = mei_hbm_cl_flow_control_req(dev, cl); 306 if (ret) { 307 cl->status = ret; 308 cb->buf_idx = 0; 309 list_move_tail(&cb->list, cmpl_list); 310 return ret; 311 } 312 313 pm_runtime_mark_last_busy(dev->dev); 314 pm_request_autosuspend(dev->dev); 315 316 list_move_tail(&cb->list, &cl->rd_pending); 317 318 return 0; 319 } 320 321 static inline bool hdr_is_hbm(struct mei_msg_hdr *mei_hdr) 322 { 323 return mei_hdr->host_addr == 0 && mei_hdr->me_addr == 0; 324 } 325 326 static inline bool hdr_is_fixed(struct mei_msg_hdr *mei_hdr) 327 { 328 return mei_hdr->host_addr == 0 && mei_hdr->me_addr != 0; 329 } 330 331 static inline int hdr_is_valid(u32 msg_hdr) 332 { 333 struct mei_msg_hdr *mei_hdr; 334 u32 expected_len = 0; 335 336 mei_hdr = (struct mei_msg_hdr *)&msg_hdr; 337 if (!msg_hdr || mei_hdr->reserved) 338 return -EBADMSG; 339 340 if (mei_hdr->dma_ring) 341 expected_len += MEI_SLOT_SIZE; 342 if (mei_hdr->extended) 343 expected_len += MEI_SLOT_SIZE; 344 if (mei_hdr->length < expected_len) 345 return -EBADMSG; 346 347 return 0; 348 } 349 350 /** 351 * mei_irq_read_handler - bottom half read routine after ISR to 352 * handle the read processing. 353 * 354 * @dev: the device structure 355 * @cmpl_list: An instance of our list structure 356 * @slots: slots to read. 357 * 358 * Return: 0 on success, <0 on failure. 359 */ 360 int mei_irq_read_handler(struct mei_device *dev, 361 struct list_head *cmpl_list, s32 *slots) 362 { 363 struct mei_msg_hdr *mei_hdr; 364 struct mei_ext_meta_hdr *meta_hdr = NULL; 365 struct mei_cl *cl; 366 int ret; 367 u32 hdr_size_left; 368 u32 hdr_size_ext; 369 int i; 370 int ext_hdr_end; 371 372 if (!dev->rd_msg_hdr[0]) { 373 dev->rd_msg_hdr[0] = mei_read_hdr(dev); 374 dev->rd_msg_hdr_count = 1; 375 (*slots)--; 376 dev_dbg(dev->dev, "slots =%08x.\n", *slots); 377 378 ret = hdr_is_valid(dev->rd_msg_hdr[0]); 379 if (ret) { 380 dev_err(dev->dev, "corrupted message header 0x%08X\n", 381 dev->rd_msg_hdr[0]); 382 goto end; 383 } 384 } 385 386 mei_hdr = (struct mei_msg_hdr *)dev->rd_msg_hdr; 387 dev_dbg(dev->dev, MEI_HDR_FMT, MEI_HDR_PRM(mei_hdr)); 388 389 if (mei_slots2data(*slots) < mei_hdr->length) { 390 dev_err(dev->dev, "less data available than length=%08x.\n", 391 *slots); 392 /* we can't read the message */ 393 ret = -ENODATA; 394 goto end; 395 } 396 397 ext_hdr_end = 1; 398 hdr_size_left = mei_hdr->length; 399 400 if (mei_hdr->extended) { 401 if (!dev->rd_msg_hdr[1]) { 402 dev->rd_msg_hdr[1] = mei_read_hdr(dev); 403 dev->rd_msg_hdr_count++; 404 (*slots)--; 405 dev_dbg(dev->dev, "extended header is %08x\n", dev->rd_msg_hdr[1]); 406 } 407 meta_hdr = ((struct mei_ext_meta_hdr *)&dev->rd_msg_hdr[1]); 408 if (check_add_overflow((u32)sizeof(*meta_hdr), 409 mei_slots2data(meta_hdr->size), 410 &hdr_size_ext)) { 411 dev_err(dev->dev, "extended message size too big %d\n", 412 meta_hdr->size); 413 return -EBADMSG; 414 } 415 if (hdr_size_left < hdr_size_ext) { 416 dev_err(dev->dev, "corrupted message header len %d\n", 417 mei_hdr->length); 418 return -EBADMSG; 419 } 420 hdr_size_left -= hdr_size_ext; 421 422 ext_hdr_end = meta_hdr->size + 2; 423 for (i = dev->rd_msg_hdr_count; i < ext_hdr_end; i++) { 424 dev->rd_msg_hdr[i] = mei_read_hdr(dev); 425 dev_dbg(dev->dev, "extended header %d is %08x\n", i, 426 dev->rd_msg_hdr[i]); 427 dev->rd_msg_hdr_count++; 428 (*slots)--; 429 } 430 } 431 432 if (mei_hdr->dma_ring) { 433 if (hdr_size_left != sizeof(dev->rd_msg_hdr[ext_hdr_end])) { 434 dev_err(dev->dev, "corrupted message header len %d\n", 435 mei_hdr->length); 436 return -EBADMSG; 437 } 438 439 dev->rd_msg_hdr[ext_hdr_end] = mei_read_hdr(dev); 440 dev->rd_msg_hdr_count++; 441 (*slots)--; 442 mei_hdr->length -= sizeof(dev->rd_msg_hdr[ext_hdr_end]); 443 } 444 445 /* HBM message */ 446 if (hdr_is_hbm(mei_hdr)) { 447 ret = mei_hbm_dispatch(dev, mei_hdr); 448 if (ret) { 449 dev_dbg(dev->dev, "mei_hbm_dispatch failed ret = %d\n", 450 ret); 451 goto end; 452 } 453 goto reset_slots; 454 } 455 456 /* find recipient cl */ 457 list_for_each_entry(cl, &dev->file_list, link) { 458 if (mei_cl_hbm_equal(cl, mei_hdr)) { 459 cl_dbg(dev, cl, "got a message\n"); 460 ret = mei_cl_irq_read_msg(cl, mei_hdr, meta_hdr, cmpl_list); 461 goto reset_slots; 462 } 463 } 464 465 /* if no recipient cl was found we assume corrupted header */ 466 /* A message for not connected fixed address clients 467 * should be silently discarded 468 * On power down client may be force cleaned, 469 * silently discard such messages 470 */ 471 if (hdr_is_fixed(mei_hdr) || 472 dev->dev_state == MEI_DEV_POWER_DOWN) { 473 mei_irq_discard_msg(dev, mei_hdr, mei_hdr->length); 474 ret = 0; 475 goto reset_slots; 476 } 477 dev_err(dev->dev, "no destination client found 0x%08X\n", dev->rd_msg_hdr[0]); 478 ret = -EBADMSG; 479 goto end; 480 481 reset_slots: 482 /* reset the number of slots and header */ 483 memset(dev->rd_msg_hdr, 0, sizeof(dev->rd_msg_hdr)); 484 dev->rd_msg_hdr_count = 0; 485 *slots = mei_count_full_read_slots(dev); 486 if (*slots == -EOVERFLOW) { 487 /* overflow - reset */ 488 dev_err(dev->dev, "resetting due to slots overflow.\n"); 489 /* set the event since message has been read */ 490 ret = -ERANGE; 491 goto end; 492 } 493 end: 494 return ret; 495 } 496 EXPORT_SYMBOL_GPL(mei_irq_read_handler); 497 498 499 /** 500 * mei_irq_write_handler - dispatch write requests 501 * after irq received 502 * 503 * @dev: the device structure 504 * @cmpl_list: An instance of our list structure 505 * 506 * Return: 0 on success, <0 on failure. 507 */ 508 int mei_irq_write_handler(struct mei_device *dev, struct list_head *cmpl_list) 509 { 510 511 struct mei_cl *cl; 512 struct mei_cl_cb *cb, *next; 513 s32 slots; 514 int ret; 515 516 517 if (!mei_hbuf_acquire(dev)) 518 return 0; 519 520 slots = mei_hbuf_empty_slots(dev); 521 if (slots < 0) 522 return -EOVERFLOW; 523 524 if (slots == 0) 525 return -EMSGSIZE; 526 527 /* complete all waiting for write CB */ 528 dev_dbg(dev->dev, "complete all waiting for write cb.\n"); 529 530 list_for_each_entry_safe(cb, next, &dev->write_waiting_list, list) { 531 cl = cb->cl; 532 533 cl->status = 0; 534 cl_dbg(dev, cl, "MEI WRITE COMPLETE\n"); 535 cl->writing_state = MEI_WRITE_COMPLETE; 536 list_move_tail(&cb->list, cmpl_list); 537 } 538 539 /* complete control write list CB */ 540 dev_dbg(dev->dev, "complete control write list cb.\n"); 541 list_for_each_entry_safe(cb, next, &dev->ctrl_wr_list, list) { 542 cl = cb->cl; 543 switch (cb->fop_type) { 544 case MEI_FOP_DISCONNECT: 545 /* send disconnect message */ 546 ret = mei_cl_irq_disconnect(cl, cb, cmpl_list); 547 if (ret) 548 return ret; 549 550 break; 551 case MEI_FOP_READ: 552 /* send flow control message */ 553 ret = mei_cl_irq_read(cl, cb, cmpl_list); 554 if (ret) 555 return ret; 556 557 break; 558 case MEI_FOP_CONNECT: 559 /* connect message */ 560 ret = mei_cl_irq_connect(cl, cb, cmpl_list); 561 if (ret) 562 return ret; 563 564 break; 565 case MEI_FOP_DISCONNECT_RSP: 566 /* send disconnect resp */ 567 ret = mei_cl_irq_disconnect_rsp(cl, cb, cmpl_list); 568 if (ret) 569 return ret; 570 break; 571 572 case MEI_FOP_NOTIFY_START: 573 case MEI_FOP_NOTIFY_STOP: 574 ret = mei_cl_irq_notify(cl, cb, cmpl_list); 575 if (ret) 576 return ret; 577 break; 578 case MEI_FOP_DMA_MAP: 579 ret = mei_cl_irq_dma_map(cl, cb, cmpl_list); 580 if (ret) 581 return ret; 582 break; 583 case MEI_FOP_DMA_UNMAP: 584 ret = mei_cl_irq_dma_unmap(cl, cb, cmpl_list); 585 if (ret) 586 return ret; 587 break; 588 default: 589 BUG(); 590 } 591 592 } 593 /* complete write list CB */ 594 dev_dbg(dev->dev, "complete write list cb.\n"); 595 list_for_each_entry_safe(cb, next, &dev->write_list, list) { 596 cl = cb->cl; 597 ret = mei_cl_irq_write(cl, cb, cmpl_list); 598 if (ret) 599 return ret; 600 } 601 return 0; 602 } 603 EXPORT_SYMBOL_GPL(mei_irq_write_handler); 604 605 606 /** 607 * mei_connect_timeout - connect/disconnect timeouts 608 * 609 * @cl: host client 610 */ 611 static void mei_connect_timeout(struct mei_cl *cl) 612 { 613 struct mei_device *dev = cl->dev; 614 615 if (cl->state == MEI_FILE_CONNECTING) { 616 if (dev->hbm_f_dot_supported) { 617 cl->state = MEI_FILE_DISCONNECT_REQUIRED; 618 wake_up(&cl->wait); 619 return; 620 } 621 } 622 mei_reset(dev); 623 } 624 625 #define MEI_STALL_TIMER_FREQ (2 * HZ) 626 /** 627 * mei_schedule_stall_timer - re-arm stall_timer work 628 * 629 * Schedule stall timer 630 * 631 * @dev: the device structure 632 */ 633 void mei_schedule_stall_timer(struct mei_device *dev) 634 { 635 schedule_delayed_work(&dev->timer_work, MEI_STALL_TIMER_FREQ); 636 } 637 638 /** 639 * mei_timer - timer function. 640 * 641 * @work: pointer to the work_struct structure 642 * 643 */ 644 void mei_timer(struct work_struct *work) 645 { 646 struct mei_cl *cl; 647 struct mei_device *dev = container_of(work, 648 struct mei_device, timer_work.work); 649 bool reschedule_timer = false; 650 651 mutex_lock(&dev->device_lock); 652 653 /* Catch interrupt stalls during HBM init handshake */ 654 if (dev->dev_state == MEI_DEV_INIT_CLIENTS && 655 dev->hbm_state != MEI_HBM_IDLE) { 656 657 if (dev->init_clients_timer) { 658 if (--dev->init_clients_timer == 0) { 659 dev_err(dev->dev, "timer: init clients timeout hbm_state = %d.\n", 660 dev->hbm_state); 661 mei_reset(dev); 662 goto out; 663 } 664 reschedule_timer = true; 665 } 666 } 667 668 if (dev->dev_state != MEI_DEV_ENABLED) 669 goto out; 670 671 /*** connect/disconnect timeouts ***/ 672 list_for_each_entry(cl, &dev->file_list, link) { 673 if (cl->timer_count) { 674 if (--cl->timer_count == 0) { 675 dev_err(dev->dev, "timer: connect/disconnect timeout.\n"); 676 mei_connect_timeout(cl); 677 goto out; 678 } 679 reschedule_timer = true; 680 } 681 } 682 683 out: 684 if (dev->dev_state != MEI_DEV_DISABLED && reschedule_timer) 685 mei_schedule_stall_timer(dev); 686 687 mutex_unlock(&dev->device_lock); 688 } 689