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(cl, 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 size_t buf_sz; 106 107 cb = list_first_entry_or_null(&cl->rd_pending, struct mei_cl_cb, list); 108 if (!cb) { 109 if (!mei_cl_is_fixed_address(cl)) { 110 cl_err(dev, cl, "pending read cb not found\n"); 111 goto discard; 112 } 113 cb = mei_cl_alloc_cb(cl, mei_cl_mtu(cl), MEI_FOP_READ, cl->fp); 114 if (!cb) 115 goto discard; 116 list_add_tail(&cb->list, &cl->rd_pending); 117 } 118 119 if (!mei_cl_is_connected(cl)) { 120 cl_dbg(dev, cl, "not connected\n"); 121 cb->status = -ENODEV; 122 goto discard; 123 } 124 125 buf_sz = mei_hdr->length + cb->buf_idx; 126 /* catch for integer overflow */ 127 if (buf_sz < cb->buf_idx) { 128 cl_err(dev, cl, "message is too big len %d idx %zu\n", 129 mei_hdr->length, cb->buf_idx); 130 cb->status = -EMSGSIZE; 131 goto discard; 132 } 133 134 if (cb->buf.size < buf_sz) { 135 cl_dbg(dev, cl, "message overflow. size %zu len %d idx %zu\n", 136 cb->buf.size, mei_hdr->length, cb->buf_idx); 137 cb->status = -EMSGSIZE; 138 goto discard; 139 } 140 141 mei_read_slots(dev, cb->buf.data + cb->buf_idx, mei_hdr->length); 142 143 cb->buf_idx += mei_hdr->length; 144 145 if (mei_hdr->msg_complete) { 146 cl_dbg(dev, cl, "completed read length = %zu\n", cb->buf_idx); 147 list_move_tail(&cb->list, &complete_list->list); 148 } else { 149 pm_runtime_mark_last_busy(dev->dev); 150 pm_request_autosuspend(dev->dev); 151 } 152 153 return 0; 154 155 discard: 156 if (cb) 157 list_move_tail(&cb->list, &complete_list->list); 158 mei_irq_discard_msg(dev, mei_hdr); 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 if (!list_empty(&cl->rd_pending)) 210 return 0; 211 212 msg_slots = mei_data2slots(sizeof(struct hbm_flow_control)); 213 slots = mei_hbuf_empty_slots(dev); 214 215 if (slots < msg_slots) 216 return -EMSGSIZE; 217 218 ret = mei_hbm_cl_flow_control_req(dev, cl); 219 if (ret) { 220 cl->status = ret; 221 cb->buf_idx = 0; 222 list_move_tail(&cb->list, &cmpl_list->list); 223 return ret; 224 } 225 226 list_move_tail(&cb->list, &cl->rd_pending); 227 228 return 0; 229 } 230 231 static inline bool hdr_is_hbm(struct mei_msg_hdr *mei_hdr) 232 { 233 return mei_hdr->host_addr == 0 && mei_hdr->me_addr == 0; 234 } 235 236 static inline bool hdr_is_fixed(struct mei_msg_hdr *mei_hdr) 237 { 238 return mei_hdr->host_addr == 0 && mei_hdr->me_addr != 0; 239 } 240 241 /** 242 * mei_irq_read_handler - bottom half read routine after ISR to 243 * handle the read processing. 244 * 245 * @dev: the device structure 246 * @cmpl_list: An instance of our list structure 247 * @slots: slots to read. 248 * 249 * Return: 0 on success, <0 on failure. 250 */ 251 int mei_irq_read_handler(struct mei_device *dev, 252 struct mei_cl_cb *cmpl_list, s32 *slots) 253 { 254 struct mei_msg_hdr *mei_hdr; 255 struct mei_cl *cl; 256 int ret; 257 258 if (!dev->rd_msg_hdr) { 259 dev->rd_msg_hdr = mei_read_hdr(dev); 260 (*slots)--; 261 dev_dbg(dev->dev, "slots =%08x.\n", *slots); 262 } 263 mei_hdr = (struct mei_msg_hdr *) &dev->rd_msg_hdr; 264 dev_dbg(dev->dev, MEI_HDR_FMT, MEI_HDR_PRM(mei_hdr)); 265 266 if (mei_hdr->reserved || !dev->rd_msg_hdr) { 267 dev_err(dev->dev, "corrupted message header 0x%08X\n", 268 dev->rd_msg_hdr); 269 ret = -EBADMSG; 270 goto end; 271 } 272 273 if (mei_slots2data(*slots) < mei_hdr->length) { 274 dev_err(dev->dev, "less data available than length=%08x.\n", 275 *slots); 276 /* we can't read the message */ 277 ret = -ENODATA; 278 goto end; 279 } 280 281 /* HBM message */ 282 if (hdr_is_hbm(mei_hdr)) { 283 ret = mei_hbm_dispatch(dev, mei_hdr); 284 if (ret) { 285 dev_dbg(dev->dev, "mei_hbm_dispatch failed ret = %d\n", 286 ret); 287 goto end; 288 } 289 goto reset_slots; 290 } 291 292 /* find recipient cl */ 293 list_for_each_entry(cl, &dev->file_list, link) { 294 if (mei_cl_hbm_equal(cl, mei_hdr)) { 295 cl_dbg(dev, cl, "got a message\n"); 296 break; 297 } 298 } 299 300 /* if no recipient cl was found we assume corrupted header */ 301 if (&cl->link == &dev->file_list) { 302 /* A message for not connected fixed address clients 303 * should be silently discarded 304 */ 305 if (hdr_is_fixed(mei_hdr)) { 306 mei_irq_discard_msg(dev, mei_hdr); 307 ret = 0; 308 goto reset_slots; 309 } 310 dev_err(dev->dev, "no destination client found 0x%08X\n", 311 dev->rd_msg_hdr); 312 ret = -EBADMSG; 313 goto end; 314 } 315 316 if (cl == &dev->iamthif_cl) { 317 ret = mei_amthif_irq_read_msg(cl, mei_hdr, cmpl_list); 318 } else { 319 ret = mei_cl_irq_read_msg(cl, mei_hdr, cmpl_list); 320 } 321 322 323 reset_slots: 324 /* reset the number of slots and header */ 325 *slots = mei_count_full_read_slots(dev); 326 dev->rd_msg_hdr = 0; 327 328 if (*slots == -EOVERFLOW) { 329 /* overflow - reset */ 330 dev_err(dev->dev, "resetting due to slots overflow.\n"); 331 /* set the event since message has been read */ 332 ret = -ERANGE; 333 goto end; 334 } 335 end: 336 return ret; 337 } 338 EXPORT_SYMBOL_GPL(mei_irq_read_handler); 339 340 341 /** 342 * mei_irq_write_handler - dispatch write requests 343 * after irq received 344 * 345 * @dev: the device structure 346 * @cmpl_list: An instance of our list structure 347 * 348 * Return: 0 on success, <0 on failure. 349 */ 350 int mei_irq_write_handler(struct mei_device *dev, struct mei_cl_cb *cmpl_list) 351 { 352 353 struct mei_cl *cl; 354 struct mei_cl_cb *cb, *next; 355 struct mei_cl_cb *list; 356 s32 slots; 357 int ret; 358 359 360 if (!mei_hbuf_acquire(dev)) 361 return 0; 362 363 slots = mei_hbuf_empty_slots(dev); 364 if (slots <= 0) 365 return -EMSGSIZE; 366 367 /* complete all waiting for write CB */ 368 dev_dbg(dev->dev, "complete all waiting for write cb.\n"); 369 370 list = &dev->write_waiting_list; 371 list_for_each_entry_safe(cb, next, &list->list, list) { 372 cl = cb->cl; 373 374 cl->status = 0; 375 cl_dbg(dev, cl, "MEI WRITE COMPLETE\n"); 376 cl->writing_state = MEI_WRITE_COMPLETE; 377 list_move_tail(&cb->list, &cmpl_list->list); 378 } 379 380 /* complete control write list CB */ 381 dev_dbg(dev->dev, "complete control write list cb.\n"); 382 list_for_each_entry_safe(cb, next, &dev->ctrl_wr_list.list, list) { 383 cl = cb->cl; 384 switch (cb->fop_type) { 385 case MEI_FOP_DISCONNECT: 386 /* send disconnect message */ 387 ret = mei_cl_irq_disconnect(cl, cb, cmpl_list); 388 if (ret) 389 return ret; 390 391 break; 392 case MEI_FOP_READ: 393 /* send flow control message */ 394 ret = mei_cl_irq_read(cl, cb, cmpl_list); 395 if (ret) 396 return ret; 397 398 break; 399 case MEI_FOP_CONNECT: 400 /* connect message */ 401 ret = mei_cl_irq_connect(cl, cb, cmpl_list); 402 if (ret) 403 return ret; 404 405 break; 406 case MEI_FOP_DISCONNECT_RSP: 407 /* send disconnect resp */ 408 ret = mei_cl_irq_disconnect_rsp(cl, cb, cmpl_list); 409 if (ret) 410 return ret; 411 break; 412 413 case MEI_FOP_NOTIFY_START: 414 case MEI_FOP_NOTIFY_STOP: 415 ret = mei_cl_irq_notify(cl, cb, cmpl_list); 416 if (ret) 417 return ret; 418 break; 419 default: 420 BUG(); 421 } 422 423 } 424 /* complete write list CB */ 425 dev_dbg(dev->dev, "complete write list cb.\n"); 426 list_for_each_entry_safe(cb, next, &dev->write_list.list, list) { 427 cl = cb->cl; 428 if (cl == &dev->iamthif_cl) 429 ret = mei_amthif_irq_write(cl, cb, cmpl_list); 430 else 431 ret = mei_cl_irq_write(cl, cb, cmpl_list); 432 if (ret) 433 return ret; 434 } 435 return 0; 436 } 437 EXPORT_SYMBOL_GPL(mei_irq_write_handler); 438 439 440 /** 441 * mei_connect_timeout - connect/disconnect timeouts 442 * 443 * @cl: host client 444 */ 445 static void mei_connect_timeout(struct mei_cl *cl) 446 { 447 struct mei_device *dev = cl->dev; 448 449 if (cl->state == MEI_FILE_CONNECTING) { 450 if (dev->hbm_f_dot_supported) { 451 cl->state = MEI_FILE_DISCONNECT_REQUIRED; 452 wake_up(&cl->wait); 453 return; 454 } 455 } 456 mei_reset(dev); 457 } 458 459 #define MEI_STALL_TIMER_FREQ (2 * HZ) 460 /** 461 * mei_schedule_stall_timer - re-arm stall_timer work 462 * 463 * Schedule stall timer 464 * 465 * @dev: the device structure 466 */ 467 void mei_schedule_stall_timer(struct mei_device *dev) 468 { 469 schedule_delayed_work(&dev->timer_work, MEI_STALL_TIMER_FREQ); 470 } 471 472 /** 473 * mei_timer - timer function. 474 * 475 * @work: pointer to the work_struct structure 476 * 477 */ 478 void mei_timer(struct work_struct *work) 479 { 480 struct mei_cl *cl; 481 struct mei_device *dev = container_of(work, 482 struct mei_device, timer_work.work); 483 bool reschedule_timer = false; 484 485 mutex_lock(&dev->device_lock); 486 487 /* Catch interrupt stalls during HBM init handshake */ 488 if (dev->dev_state == MEI_DEV_INIT_CLIENTS && 489 dev->hbm_state != MEI_HBM_IDLE) { 490 491 if (dev->init_clients_timer) { 492 if (--dev->init_clients_timer == 0) { 493 dev_err(dev->dev, "timer: init clients timeout hbm_state = %d.\n", 494 dev->hbm_state); 495 mei_reset(dev); 496 goto out; 497 } 498 reschedule_timer = true; 499 } 500 } 501 502 if (dev->dev_state != MEI_DEV_ENABLED) 503 goto out; 504 505 /*** connect/disconnect timeouts ***/ 506 list_for_each_entry(cl, &dev->file_list, link) { 507 if (cl->timer_count) { 508 if (--cl->timer_count == 0) { 509 dev_err(dev->dev, "timer: connect/disconnect timeout.\n"); 510 mei_connect_timeout(cl); 511 goto out; 512 } 513 reschedule_timer = true; 514 } 515 } 516 517 if (!mei_cl_is_connected(&dev->iamthif_cl)) 518 goto out; 519 520 if (dev->iamthif_stall_timer) { 521 if (--dev->iamthif_stall_timer == 0) { 522 dev_err(dev->dev, "timer: amthif hanged.\n"); 523 mei_reset(dev); 524 525 mei_amthif_run_next_cmd(dev); 526 goto out; 527 } 528 reschedule_timer = true; 529 } 530 531 out: 532 if (dev->dev_state != MEI_DEV_DISABLED && reschedule_timer) 533 mei_schedule_stall_timer(dev); 534 535 mutex_unlock(&dev->device_lock); 536 } 537