1 // SPDX-License-Identifier: GPL-2.0 2 /** 3 * xhci-dbgcap.c - xHCI debug capability support 4 * 5 * Copyright (C) 2017 Intel Corporation 6 * 7 * Author: Lu Baolu <baolu.lu@linux.intel.com> 8 */ 9 #include <linux/dma-mapping.h> 10 #include <linux/slab.h> 11 #include <linux/nls.h> 12 13 #include "xhci.h" 14 #include "xhci-trace.h" 15 #include "xhci-dbgcap.h" 16 17 static inline void * 18 dbc_dma_alloc_coherent(struct xhci_hcd *xhci, size_t size, 19 dma_addr_t *dma_handle, gfp_t flags) 20 { 21 void *vaddr; 22 23 vaddr = dma_alloc_coherent(xhci_to_hcd(xhci)->self.sysdev, 24 size, dma_handle, flags); 25 return vaddr; 26 } 27 28 static inline void 29 dbc_dma_free_coherent(struct xhci_hcd *xhci, size_t size, 30 void *cpu_addr, dma_addr_t dma_handle) 31 { 32 if (cpu_addr) 33 dma_free_coherent(xhci_to_hcd(xhci)->self.sysdev, 34 size, cpu_addr, dma_handle); 35 } 36 37 static u32 xhci_dbc_populate_strings(struct dbc_str_descs *strings) 38 { 39 struct usb_string_descriptor *s_desc; 40 u32 string_length; 41 42 /* Serial string: */ 43 s_desc = (struct usb_string_descriptor *)strings->serial; 44 utf8s_to_utf16s(DBC_STRING_SERIAL, strlen(DBC_STRING_SERIAL), 45 UTF16_LITTLE_ENDIAN, (wchar_t *)s_desc->wData, 46 DBC_MAX_STRING_LENGTH); 47 48 s_desc->bLength = (strlen(DBC_STRING_SERIAL) + 1) * 2; 49 s_desc->bDescriptorType = USB_DT_STRING; 50 string_length = s_desc->bLength; 51 string_length <<= 8; 52 53 /* Product string: */ 54 s_desc = (struct usb_string_descriptor *)strings->product; 55 utf8s_to_utf16s(DBC_STRING_PRODUCT, strlen(DBC_STRING_PRODUCT), 56 UTF16_LITTLE_ENDIAN, (wchar_t *)s_desc->wData, 57 DBC_MAX_STRING_LENGTH); 58 59 s_desc->bLength = (strlen(DBC_STRING_PRODUCT) + 1) * 2; 60 s_desc->bDescriptorType = USB_DT_STRING; 61 string_length += s_desc->bLength; 62 string_length <<= 8; 63 64 /* Manufacture string: */ 65 s_desc = (struct usb_string_descriptor *)strings->manufacturer; 66 utf8s_to_utf16s(DBC_STRING_MANUFACTURER, 67 strlen(DBC_STRING_MANUFACTURER), 68 UTF16_LITTLE_ENDIAN, (wchar_t *)s_desc->wData, 69 DBC_MAX_STRING_LENGTH); 70 71 s_desc->bLength = (strlen(DBC_STRING_MANUFACTURER) + 1) * 2; 72 s_desc->bDescriptorType = USB_DT_STRING; 73 string_length += s_desc->bLength; 74 string_length <<= 8; 75 76 /* String0: */ 77 strings->string0[0] = 4; 78 strings->string0[1] = USB_DT_STRING; 79 strings->string0[2] = 0x09; 80 strings->string0[3] = 0x04; 81 string_length += 4; 82 83 return string_length; 84 } 85 86 static void xhci_dbc_init_contexts(struct xhci_hcd *xhci, u32 string_length) 87 { 88 struct xhci_dbc *dbc; 89 struct dbc_info_context *info; 90 struct xhci_ep_ctx *ep_ctx; 91 u32 dev_info; 92 dma_addr_t deq, dma; 93 unsigned int max_burst; 94 95 dbc = xhci->dbc; 96 if (!dbc) 97 return; 98 99 /* Populate info Context: */ 100 info = (struct dbc_info_context *)dbc->ctx->bytes; 101 dma = dbc->string_dma; 102 info->string0 = cpu_to_le64(dma); 103 info->manufacturer = cpu_to_le64(dma + DBC_MAX_STRING_LENGTH); 104 info->product = cpu_to_le64(dma + DBC_MAX_STRING_LENGTH * 2); 105 info->serial = cpu_to_le64(dma + DBC_MAX_STRING_LENGTH * 3); 106 info->length = cpu_to_le32(string_length); 107 108 /* Populate bulk out endpoint context: */ 109 ep_ctx = dbc_bulkout_ctx(dbc); 110 max_burst = DBC_CTRL_MAXBURST(readl(&dbc->regs->control)); 111 deq = dbc_bulkout_enq(dbc); 112 ep_ctx->ep_info = 0; 113 ep_ctx->ep_info2 = dbc_epctx_info2(BULK_OUT_EP, 1024, max_burst); 114 ep_ctx->deq = cpu_to_le64(deq | dbc->ring_out->cycle_state); 115 116 /* Populate bulk in endpoint context: */ 117 ep_ctx = dbc_bulkin_ctx(dbc); 118 deq = dbc_bulkin_enq(dbc); 119 ep_ctx->ep_info = 0; 120 ep_ctx->ep_info2 = dbc_epctx_info2(BULK_IN_EP, 1024, max_burst); 121 ep_ctx->deq = cpu_to_le64(deq | dbc->ring_in->cycle_state); 122 123 /* Set DbC context and info registers: */ 124 xhci_write_64(xhci, dbc->ctx->dma, &dbc->regs->dccp); 125 126 dev_info = cpu_to_le32((DBC_VENDOR_ID << 16) | DBC_PROTOCOL); 127 writel(dev_info, &dbc->regs->devinfo1); 128 129 dev_info = cpu_to_le32((DBC_DEVICE_REV << 16) | DBC_PRODUCT_ID); 130 writel(dev_info, &dbc->regs->devinfo2); 131 } 132 133 static void xhci_dbc_giveback(struct dbc_request *req, int status) 134 __releases(&dbc->lock) 135 __acquires(&dbc->lock) 136 { 137 struct dbc_ep *dep = req->dep; 138 struct xhci_dbc *dbc = dep->dbc; 139 struct xhci_hcd *xhci = dbc->xhci; 140 struct device *dev = xhci_to_hcd(dbc->xhci)->self.sysdev; 141 142 list_del_init(&req->list_pending); 143 req->trb_dma = 0; 144 req->trb = NULL; 145 146 if (req->status == -EINPROGRESS) 147 req->status = status; 148 149 trace_xhci_dbc_giveback_request(req); 150 151 dma_unmap_single(dev, 152 req->dma, 153 req->length, 154 dbc_ep_dma_direction(dep)); 155 156 /* Give back the transfer request: */ 157 spin_unlock(&dbc->lock); 158 req->complete(xhci, req); 159 spin_lock(&dbc->lock); 160 } 161 162 static void xhci_dbc_flush_single_request(struct dbc_request *req) 163 { 164 union xhci_trb *trb = req->trb; 165 166 trb->generic.field[0] = 0; 167 trb->generic.field[1] = 0; 168 trb->generic.field[2] = 0; 169 trb->generic.field[3] &= cpu_to_le32(TRB_CYCLE); 170 trb->generic.field[3] |= cpu_to_le32(TRB_TYPE(TRB_TR_NOOP)); 171 172 xhci_dbc_giveback(req, -ESHUTDOWN); 173 } 174 175 static void xhci_dbc_flush_endpoint_requests(struct dbc_ep *dep) 176 { 177 struct dbc_request *req, *tmp; 178 179 list_for_each_entry_safe(req, tmp, &dep->list_pending, list_pending) 180 xhci_dbc_flush_single_request(req); 181 } 182 183 static void xhci_dbc_flush_requests(struct xhci_dbc *dbc) 184 { 185 xhci_dbc_flush_endpoint_requests(&dbc->eps[BULK_OUT]); 186 xhci_dbc_flush_endpoint_requests(&dbc->eps[BULK_IN]); 187 } 188 189 struct dbc_request * 190 dbc_alloc_request(struct dbc_ep *dep, gfp_t gfp_flags) 191 { 192 struct dbc_request *req; 193 194 req = kzalloc(sizeof(*req), gfp_flags); 195 if (!req) 196 return NULL; 197 198 req->dep = dep; 199 INIT_LIST_HEAD(&req->list_pending); 200 INIT_LIST_HEAD(&req->list_pool); 201 req->direction = dep->direction; 202 203 trace_xhci_dbc_alloc_request(req); 204 205 return req; 206 } 207 208 void 209 dbc_free_request(struct dbc_ep *dep, struct dbc_request *req) 210 { 211 trace_xhci_dbc_free_request(req); 212 213 kfree(req); 214 } 215 216 static void 217 xhci_dbc_queue_trb(struct xhci_ring *ring, u32 field1, 218 u32 field2, u32 field3, u32 field4) 219 { 220 union xhci_trb *trb, *next; 221 222 trb = ring->enqueue; 223 trb->generic.field[0] = cpu_to_le32(field1); 224 trb->generic.field[1] = cpu_to_le32(field2); 225 trb->generic.field[2] = cpu_to_le32(field3); 226 trb->generic.field[3] = cpu_to_le32(field4); 227 228 trace_xhci_dbc_gadget_ep_queue(ring, &trb->generic); 229 230 ring->num_trbs_free--; 231 next = ++(ring->enqueue); 232 if (TRB_TYPE_LINK_LE32(next->link.control)) { 233 next->link.control ^= cpu_to_le32(TRB_CYCLE); 234 ring->enqueue = ring->enq_seg->trbs; 235 ring->cycle_state ^= 1; 236 } 237 } 238 239 static int xhci_dbc_queue_bulk_tx(struct dbc_ep *dep, 240 struct dbc_request *req) 241 { 242 u64 addr; 243 union xhci_trb *trb; 244 unsigned int num_trbs; 245 struct xhci_dbc *dbc = dep->dbc; 246 struct xhci_ring *ring = dep->ring; 247 u32 length, control, cycle; 248 249 num_trbs = count_trbs(req->dma, req->length); 250 WARN_ON(num_trbs != 1); 251 if (ring->num_trbs_free < num_trbs) 252 return -EBUSY; 253 254 addr = req->dma; 255 trb = ring->enqueue; 256 cycle = ring->cycle_state; 257 length = TRB_LEN(req->length); 258 control = TRB_TYPE(TRB_NORMAL) | TRB_IOC; 259 260 if (cycle) 261 control &= cpu_to_le32(~TRB_CYCLE); 262 else 263 control |= cpu_to_le32(TRB_CYCLE); 264 265 req->trb = ring->enqueue; 266 req->trb_dma = xhci_trb_virt_to_dma(ring->enq_seg, ring->enqueue); 267 xhci_dbc_queue_trb(ring, 268 lower_32_bits(addr), 269 upper_32_bits(addr), 270 length, control); 271 272 /* 273 * Add a barrier between writes of trb fields and flipping 274 * the cycle bit: 275 */ 276 wmb(); 277 278 if (cycle) 279 trb->generic.field[3] |= cpu_to_le32(TRB_CYCLE); 280 else 281 trb->generic.field[3] &= cpu_to_le32(~TRB_CYCLE); 282 283 writel(DBC_DOOR_BELL_TARGET(dep->direction), &dbc->regs->doorbell); 284 285 return 0; 286 } 287 288 static int 289 dbc_ep_do_queue(struct dbc_ep *dep, struct dbc_request *req) 290 { 291 int ret; 292 struct device *dev; 293 struct xhci_dbc *dbc = dep->dbc; 294 struct xhci_hcd *xhci = dbc->xhci; 295 296 dev = xhci_to_hcd(xhci)->self.sysdev; 297 298 if (!req->length || !req->buf) 299 return -EINVAL; 300 301 req->actual = 0; 302 req->status = -EINPROGRESS; 303 304 req->dma = dma_map_single(dev, 305 req->buf, 306 req->length, 307 dbc_ep_dma_direction(dep)); 308 if (dma_mapping_error(dev, req->dma)) { 309 xhci_err(xhci, "failed to map buffer\n"); 310 return -EFAULT; 311 } 312 313 ret = xhci_dbc_queue_bulk_tx(dep, req); 314 if (ret) { 315 xhci_err(xhci, "failed to queue trbs\n"); 316 dma_unmap_single(dev, 317 req->dma, 318 req->length, 319 dbc_ep_dma_direction(dep)); 320 return -EFAULT; 321 } 322 323 list_add_tail(&req->list_pending, &dep->list_pending); 324 325 return 0; 326 } 327 328 int dbc_ep_queue(struct dbc_ep *dep, struct dbc_request *req, 329 gfp_t gfp_flags) 330 { 331 unsigned long flags; 332 struct xhci_dbc *dbc = dep->dbc; 333 int ret = -ESHUTDOWN; 334 335 spin_lock_irqsave(&dbc->lock, flags); 336 if (dbc->state == DS_CONFIGURED) 337 ret = dbc_ep_do_queue(dep, req); 338 spin_unlock_irqrestore(&dbc->lock, flags); 339 340 mod_delayed_work(system_wq, &dbc->event_work, 0); 341 342 trace_xhci_dbc_queue_request(req); 343 344 return ret; 345 } 346 347 static inline void xhci_dbc_do_eps_init(struct xhci_hcd *xhci, bool direction) 348 { 349 struct dbc_ep *dep; 350 struct xhci_dbc *dbc = xhci->dbc; 351 352 dep = &dbc->eps[direction]; 353 dep->dbc = dbc; 354 dep->direction = direction; 355 dep->ring = direction ? dbc->ring_in : dbc->ring_out; 356 357 INIT_LIST_HEAD(&dep->list_pending); 358 } 359 360 static void xhci_dbc_eps_init(struct xhci_hcd *xhci) 361 { 362 xhci_dbc_do_eps_init(xhci, BULK_OUT); 363 xhci_dbc_do_eps_init(xhci, BULK_IN); 364 } 365 366 static void xhci_dbc_eps_exit(struct xhci_hcd *xhci) 367 { 368 struct xhci_dbc *dbc = xhci->dbc; 369 370 memset(dbc->eps, 0, sizeof(struct dbc_ep) * ARRAY_SIZE(dbc->eps)); 371 } 372 373 static int xhci_dbc_mem_init(struct xhci_hcd *xhci, gfp_t flags) 374 { 375 int ret; 376 dma_addr_t deq; 377 u32 string_length; 378 struct xhci_dbc *dbc = xhci->dbc; 379 380 /* Allocate various rings for events and transfers: */ 381 dbc->ring_evt = xhci_ring_alloc(xhci, 1, 1, TYPE_EVENT, 0, flags); 382 if (!dbc->ring_evt) 383 goto evt_fail; 384 385 dbc->ring_in = xhci_ring_alloc(xhci, 1, 1, TYPE_BULK, 0, flags); 386 if (!dbc->ring_in) 387 goto in_fail; 388 389 dbc->ring_out = xhci_ring_alloc(xhci, 1, 1, TYPE_BULK, 0, flags); 390 if (!dbc->ring_out) 391 goto out_fail; 392 393 /* Allocate and populate ERST: */ 394 ret = xhci_alloc_erst(xhci, dbc->ring_evt, &dbc->erst, flags); 395 if (ret) 396 goto erst_fail; 397 398 /* Allocate context data structure: */ 399 dbc->ctx = xhci_alloc_container_ctx(xhci, XHCI_CTX_TYPE_DEVICE, flags); 400 if (!dbc->ctx) 401 goto ctx_fail; 402 403 /* Allocate the string table: */ 404 dbc->string_size = sizeof(struct dbc_str_descs); 405 dbc->string = dbc_dma_alloc_coherent(xhci, 406 dbc->string_size, 407 &dbc->string_dma, 408 flags); 409 if (!dbc->string) 410 goto string_fail; 411 412 /* Setup ERST register: */ 413 writel(dbc->erst.erst_size, &dbc->regs->ersts); 414 xhci_write_64(xhci, dbc->erst.erst_dma_addr, &dbc->regs->erstba); 415 deq = xhci_trb_virt_to_dma(dbc->ring_evt->deq_seg, 416 dbc->ring_evt->dequeue); 417 xhci_write_64(xhci, deq, &dbc->regs->erdp); 418 419 /* Setup strings and contexts: */ 420 string_length = xhci_dbc_populate_strings(dbc->string); 421 xhci_dbc_init_contexts(xhci, string_length); 422 423 xhci_dbc_eps_init(xhci); 424 dbc->state = DS_INITIALIZED; 425 426 return 0; 427 428 string_fail: 429 xhci_free_container_ctx(xhci, dbc->ctx); 430 dbc->ctx = NULL; 431 ctx_fail: 432 xhci_free_erst(xhci, &dbc->erst); 433 erst_fail: 434 xhci_ring_free(xhci, dbc->ring_out); 435 dbc->ring_out = NULL; 436 out_fail: 437 xhci_ring_free(xhci, dbc->ring_in); 438 dbc->ring_in = NULL; 439 in_fail: 440 xhci_ring_free(xhci, dbc->ring_evt); 441 dbc->ring_evt = NULL; 442 evt_fail: 443 return -ENOMEM; 444 } 445 446 static void xhci_dbc_mem_cleanup(struct xhci_hcd *xhci) 447 { 448 struct xhci_dbc *dbc = xhci->dbc; 449 450 if (!dbc) 451 return; 452 453 xhci_dbc_eps_exit(xhci); 454 455 if (dbc->string) { 456 dbc_dma_free_coherent(xhci, 457 dbc->string_size, 458 dbc->string, dbc->string_dma); 459 dbc->string = NULL; 460 } 461 462 xhci_free_container_ctx(xhci, dbc->ctx); 463 dbc->ctx = NULL; 464 465 xhci_free_erst(xhci, &dbc->erst); 466 xhci_ring_free(xhci, dbc->ring_out); 467 xhci_ring_free(xhci, dbc->ring_in); 468 xhci_ring_free(xhci, dbc->ring_evt); 469 dbc->ring_in = NULL; 470 dbc->ring_out = NULL; 471 dbc->ring_evt = NULL; 472 } 473 474 static int xhci_do_dbc_start(struct xhci_hcd *xhci) 475 { 476 int ret; 477 u32 ctrl; 478 struct xhci_dbc *dbc = xhci->dbc; 479 480 if (dbc->state != DS_DISABLED) 481 return -EINVAL; 482 483 writel(0, &dbc->regs->control); 484 ret = xhci_handshake(&dbc->regs->control, 485 DBC_CTRL_DBC_ENABLE, 486 0, 1000); 487 if (ret) 488 return ret; 489 490 ret = xhci_dbc_mem_init(xhci, GFP_ATOMIC); 491 if (ret) 492 return ret; 493 494 ctrl = readl(&dbc->regs->control); 495 writel(ctrl | DBC_CTRL_DBC_ENABLE | DBC_CTRL_PORT_ENABLE, 496 &dbc->regs->control); 497 ret = xhci_handshake(&dbc->regs->control, 498 DBC_CTRL_DBC_ENABLE, 499 DBC_CTRL_DBC_ENABLE, 1000); 500 if (ret) 501 return ret; 502 503 dbc->state = DS_ENABLED; 504 505 return 0; 506 } 507 508 static int xhci_do_dbc_stop(struct xhci_hcd *xhci) 509 { 510 struct xhci_dbc *dbc = xhci->dbc; 511 512 if (dbc->state == DS_DISABLED) 513 return -1; 514 515 writel(0, &dbc->regs->control); 516 dbc->state = DS_DISABLED; 517 518 return 0; 519 } 520 521 static int xhci_dbc_start(struct xhci_hcd *xhci) 522 { 523 int ret; 524 unsigned long flags; 525 struct xhci_dbc *dbc = xhci->dbc; 526 527 WARN_ON(!dbc); 528 529 pm_runtime_get_sync(xhci_to_hcd(xhci)->self.controller); 530 531 spin_lock_irqsave(&dbc->lock, flags); 532 ret = xhci_do_dbc_start(xhci); 533 spin_unlock_irqrestore(&dbc->lock, flags); 534 535 if (ret) { 536 pm_runtime_put(xhci_to_hcd(xhci)->self.controller); 537 return ret; 538 } 539 540 return mod_delayed_work(system_wq, &dbc->event_work, 1); 541 } 542 543 static void xhci_dbc_stop(struct xhci_hcd *xhci) 544 { 545 int ret; 546 unsigned long flags; 547 struct xhci_dbc *dbc = xhci->dbc; 548 struct dbc_port *port = &dbc->port; 549 550 WARN_ON(!dbc); 551 552 cancel_delayed_work_sync(&dbc->event_work); 553 554 if (port->registered) 555 xhci_dbc_tty_unregister_device(xhci); 556 557 spin_lock_irqsave(&dbc->lock, flags); 558 ret = xhci_do_dbc_stop(xhci); 559 spin_unlock_irqrestore(&dbc->lock, flags); 560 561 if (!ret) { 562 xhci_dbc_mem_cleanup(xhci); 563 pm_runtime_put_sync(xhci_to_hcd(xhci)->self.controller); 564 } 565 } 566 567 static void 568 dbc_handle_port_status(struct xhci_hcd *xhci, union xhci_trb *event) 569 { 570 u32 portsc; 571 struct xhci_dbc *dbc = xhci->dbc; 572 573 portsc = readl(&dbc->regs->portsc); 574 if (portsc & DBC_PORTSC_CONN_CHANGE) 575 xhci_info(xhci, "DbC port connect change\n"); 576 577 if (portsc & DBC_PORTSC_RESET_CHANGE) 578 xhci_info(xhci, "DbC port reset change\n"); 579 580 if (portsc & DBC_PORTSC_LINK_CHANGE) 581 xhci_info(xhci, "DbC port link status change\n"); 582 583 if (portsc & DBC_PORTSC_CONFIG_CHANGE) 584 xhci_info(xhci, "DbC config error change\n"); 585 586 /* Port reset change bit will be cleared in other place: */ 587 writel(portsc & ~DBC_PORTSC_RESET_CHANGE, &dbc->regs->portsc); 588 } 589 590 static void dbc_handle_xfer_event(struct xhci_hcd *xhci, union xhci_trb *event) 591 { 592 struct dbc_ep *dep; 593 struct xhci_ring *ring; 594 int ep_id; 595 int status; 596 u32 comp_code; 597 size_t remain_length; 598 struct dbc_request *req = NULL, *r; 599 600 comp_code = GET_COMP_CODE(le32_to_cpu(event->generic.field[2])); 601 remain_length = EVENT_TRB_LEN(le32_to_cpu(event->generic.field[2])); 602 ep_id = TRB_TO_EP_ID(le32_to_cpu(event->generic.field[3])); 603 dep = (ep_id == EPID_OUT) ? 604 get_out_ep(xhci) : get_in_ep(xhci); 605 ring = dep->ring; 606 607 switch (comp_code) { 608 case COMP_SUCCESS: 609 remain_length = 0; 610 /* FALLTHROUGH */ 611 case COMP_SHORT_PACKET: 612 status = 0; 613 break; 614 case COMP_TRB_ERROR: 615 case COMP_BABBLE_DETECTED_ERROR: 616 case COMP_USB_TRANSACTION_ERROR: 617 case COMP_STALL_ERROR: 618 xhci_warn(xhci, "tx error %d detected\n", comp_code); 619 status = -comp_code; 620 break; 621 default: 622 xhci_err(xhci, "unknown tx error %d\n", comp_code); 623 status = -comp_code; 624 break; 625 } 626 627 /* Match the pending request: */ 628 list_for_each_entry(r, &dep->list_pending, list_pending) { 629 if (r->trb_dma == event->trans_event.buffer) { 630 req = r; 631 break; 632 } 633 } 634 635 if (!req) { 636 xhci_warn(xhci, "no matched request\n"); 637 return; 638 } 639 640 trace_xhci_dbc_handle_transfer(ring, &req->trb->generic); 641 642 ring->num_trbs_free++; 643 req->actual = req->length - remain_length; 644 xhci_dbc_giveback(req, status); 645 } 646 647 static enum evtreturn xhci_dbc_do_handle_events(struct xhci_dbc *dbc) 648 { 649 dma_addr_t deq; 650 struct dbc_ep *dep; 651 union xhci_trb *evt; 652 u32 ctrl, portsc; 653 struct xhci_hcd *xhci = dbc->xhci; 654 bool update_erdp = false; 655 656 /* DbC state machine: */ 657 switch (dbc->state) { 658 case DS_DISABLED: 659 case DS_INITIALIZED: 660 661 return EVT_ERR; 662 case DS_ENABLED: 663 portsc = readl(&dbc->regs->portsc); 664 if (portsc & DBC_PORTSC_CONN_STATUS) { 665 dbc->state = DS_CONNECTED; 666 xhci_info(xhci, "DbC connected\n"); 667 } 668 669 return EVT_DONE; 670 case DS_CONNECTED: 671 ctrl = readl(&dbc->regs->control); 672 if (ctrl & DBC_CTRL_DBC_RUN) { 673 dbc->state = DS_CONFIGURED; 674 xhci_info(xhci, "DbC configured\n"); 675 portsc = readl(&dbc->regs->portsc); 676 writel(portsc, &dbc->regs->portsc); 677 return EVT_GSER; 678 } 679 680 return EVT_DONE; 681 case DS_CONFIGURED: 682 /* Handle cable unplug event: */ 683 portsc = readl(&dbc->regs->portsc); 684 if (!(portsc & DBC_PORTSC_PORT_ENABLED) && 685 !(portsc & DBC_PORTSC_CONN_STATUS)) { 686 xhci_info(xhci, "DbC cable unplugged\n"); 687 dbc->state = DS_ENABLED; 688 xhci_dbc_flush_requests(dbc); 689 690 return EVT_DISC; 691 } 692 693 /* Handle debug port reset event: */ 694 if (portsc & DBC_PORTSC_RESET_CHANGE) { 695 xhci_info(xhci, "DbC port reset\n"); 696 writel(portsc, &dbc->regs->portsc); 697 dbc->state = DS_ENABLED; 698 xhci_dbc_flush_requests(dbc); 699 700 return EVT_DISC; 701 } 702 703 /* Handle endpoint stall event: */ 704 ctrl = readl(&dbc->regs->control); 705 if ((ctrl & DBC_CTRL_HALT_IN_TR) || 706 (ctrl & DBC_CTRL_HALT_OUT_TR)) { 707 xhci_info(xhci, "DbC Endpoint stall\n"); 708 dbc->state = DS_STALLED; 709 710 if (ctrl & DBC_CTRL_HALT_IN_TR) { 711 dep = get_in_ep(xhci); 712 xhci_dbc_flush_endpoint_requests(dep); 713 } 714 715 if (ctrl & DBC_CTRL_HALT_OUT_TR) { 716 dep = get_out_ep(xhci); 717 xhci_dbc_flush_endpoint_requests(dep); 718 } 719 720 return EVT_DONE; 721 } 722 723 /* Clear DbC run change bit: */ 724 if (ctrl & DBC_CTRL_DBC_RUN_CHANGE) { 725 writel(ctrl, &dbc->regs->control); 726 ctrl = readl(&dbc->regs->control); 727 } 728 729 break; 730 case DS_STALLED: 731 ctrl = readl(&dbc->regs->control); 732 if (!(ctrl & DBC_CTRL_HALT_IN_TR) && 733 !(ctrl & DBC_CTRL_HALT_OUT_TR) && 734 (ctrl & DBC_CTRL_DBC_RUN)) { 735 dbc->state = DS_CONFIGURED; 736 break; 737 } 738 739 return EVT_DONE; 740 default: 741 xhci_err(xhci, "Unknown DbC state %d\n", dbc->state); 742 break; 743 } 744 745 /* Handle the events in the event ring: */ 746 evt = dbc->ring_evt->dequeue; 747 while ((le32_to_cpu(evt->event_cmd.flags) & TRB_CYCLE) == 748 dbc->ring_evt->cycle_state) { 749 /* 750 * Add a barrier between reading the cycle flag and any 751 * reads of the event's flags/data below: 752 */ 753 rmb(); 754 755 trace_xhci_dbc_handle_event(dbc->ring_evt, &evt->generic); 756 757 switch (le32_to_cpu(evt->event_cmd.flags) & TRB_TYPE_BITMASK) { 758 case TRB_TYPE(TRB_PORT_STATUS): 759 dbc_handle_port_status(xhci, evt); 760 break; 761 case TRB_TYPE(TRB_TRANSFER): 762 dbc_handle_xfer_event(xhci, evt); 763 break; 764 default: 765 break; 766 } 767 768 inc_deq(xhci, dbc->ring_evt); 769 evt = dbc->ring_evt->dequeue; 770 update_erdp = true; 771 } 772 773 /* Update event ring dequeue pointer: */ 774 if (update_erdp) { 775 deq = xhci_trb_virt_to_dma(dbc->ring_evt->deq_seg, 776 dbc->ring_evt->dequeue); 777 xhci_write_64(xhci, deq, &dbc->regs->erdp); 778 } 779 780 return EVT_DONE; 781 } 782 783 static void xhci_dbc_handle_events(struct work_struct *work) 784 { 785 int ret; 786 enum evtreturn evtr; 787 struct xhci_dbc *dbc; 788 unsigned long flags; 789 struct xhci_hcd *xhci; 790 791 dbc = container_of(to_delayed_work(work), struct xhci_dbc, event_work); 792 xhci = dbc->xhci; 793 794 spin_lock_irqsave(&dbc->lock, flags); 795 evtr = xhci_dbc_do_handle_events(dbc); 796 spin_unlock_irqrestore(&dbc->lock, flags); 797 798 switch (evtr) { 799 case EVT_GSER: 800 ret = xhci_dbc_tty_register_device(xhci); 801 if (ret) { 802 xhci_err(xhci, "failed to alloc tty device\n"); 803 break; 804 } 805 806 xhci_info(xhci, "DbC now attached to /dev/ttyDBC0\n"); 807 break; 808 case EVT_DISC: 809 xhci_dbc_tty_unregister_device(xhci); 810 break; 811 case EVT_DONE: 812 break; 813 default: 814 xhci_info(xhci, "stop handling dbc events\n"); 815 return; 816 } 817 818 mod_delayed_work(system_wq, &dbc->event_work, 1); 819 } 820 821 static void xhci_do_dbc_exit(struct xhci_hcd *xhci) 822 { 823 unsigned long flags; 824 825 spin_lock_irqsave(&xhci->lock, flags); 826 kfree(xhci->dbc); 827 xhci->dbc = NULL; 828 spin_unlock_irqrestore(&xhci->lock, flags); 829 } 830 831 static int xhci_do_dbc_init(struct xhci_hcd *xhci) 832 { 833 u32 reg; 834 struct xhci_dbc *dbc; 835 unsigned long flags; 836 void __iomem *base; 837 int dbc_cap_offs; 838 839 base = &xhci->cap_regs->hc_capbase; 840 dbc_cap_offs = xhci_find_next_ext_cap(base, 0, XHCI_EXT_CAPS_DEBUG); 841 if (!dbc_cap_offs) 842 return -ENODEV; 843 844 dbc = kzalloc(sizeof(*dbc), GFP_KERNEL); 845 if (!dbc) 846 return -ENOMEM; 847 848 dbc->regs = base + dbc_cap_offs; 849 850 /* We will avoid using DbC in xhci driver if it's in use. */ 851 reg = readl(&dbc->regs->control); 852 if (reg & DBC_CTRL_DBC_ENABLE) { 853 kfree(dbc); 854 return -EBUSY; 855 } 856 857 spin_lock_irqsave(&xhci->lock, flags); 858 if (xhci->dbc) { 859 spin_unlock_irqrestore(&xhci->lock, flags); 860 kfree(dbc); 861 return -EBUSY; 862 } 863 xhci->dbc = dbc; 864 spin_unlock_irqrestore(&xhci->lock, flags); 865 866 dbc->xhci = xhci; 867 INIT_DELAYED_WORK(&dbc->event_work, xhci_dbc_handle_events); 868 spin_lock_init(&dbc->lock); 869 870 return 0; 871 } 872 873 static ssize_t dbc_show(struct device *dev, 874 struct device_attribute *attr, 875 char *buf) 876 { 877 const char *p; 878 struct xhci_dbc *dbc; 879 struct xhci_hcd *xhci; 880 881 xhci = hcd_to_xhci(dev_get_drvdata(dev)); 882 dbc = xhci->dbc; 883 884 switch (dbc->state) { 885 case DS_DISABLED: 886 p = "disabled"; 887 break; 888 case DS_INITIALIZED: 889 p = "initialized"; 890 break; 891 case DS_ENABLED: 892 p = "enabled"; 893 break; 894 case DS_CONNECTED: 895 p = "connected"; 896 break; 897 case DS_CONFIGURED: 898 p = "configured"; 899 break; 900 case DS_STALLED: 901 p = "stalled"; 902 break; 903 default: 904 p = "unknown"; 905 } 906 907 return sprintf(buf, "%s\n", p); 908 } 909 910 static ssize_t dbc_store(struct device *dev, 911 struct device_attribute *attr, 912 const char *buf, size_t count) 913 { 914 struct xhci_hcd *xhci; 915 916 xhci = hcd_to_xhci(dev_get_drvdata(dev)); 917 918 if (!strncmp(buf, "enable", 6)) 919 xhci_dbc_start(xhci); 920 else if (!strncmp(buf, "disable", 7)) 921 xhci_dbc_stop(xhci); 922 else 923 return -EINVAL; 924 925 return count; 926 } 927 928 static DEVICE_ATTR_RW(dbc); 929 930 int xhci_dbc_init(struct xhci_hcd *xhci) 931 { 932 int ret; 933 struct device *dev = xhci_to_hcd(xhci)->self.controller; 934 935 ret = xhci_do_dbc_init(xhci); 936 if (ret) 937 goto init_err3; 938 939 ret = xhci_dbc_tty_register_driver(xhci); 940 if (ret) 941 goto init_err2; 942 943 ret = device_create_file(dev, &dev_attr_dbc); 944 if (ret) 945 goto init_err1; 946 947 return 0; 948 949 init_err1: 950 xhci_dbc_tty_unregister_driver(); 951 init_err2: 952 xhci_do_dbc_exit(xhci); 953 init_err3: 954 return ret; 955 } 956 957 void xhci_dbc_exit(struct xhci_hcd *xhci) 958 { 959 struct device *dev = xhci_to_hcd(xhci)->self.controller; 960 961 if (!xhci->dbc) 962 return; 963 964 device_remove_file(dev, &dev_attr_dbc); 965 xhci_dbc_tty_unregister_driver(); 966 xhci_dbc_stop(xhci); 967 xhci_do_dbc_exit(xhci); 968 } 969 970 #ifdef CONFIG_PM 971 int xhci_dbc_suspend(struct xhci_hcd *xhci) 972 { 973 struct xhci_dbc *dbc = xhci->dbc; 974 975 if (!dbc) 976 return 0; 977 978 if (dbc->state == DS_CONFIGURED) 979 dbc->resume_required = 1; 980 981 xhci_dbc_stop(xhci); 982 983 return 0; 984 } 985 986 int xhci_dbc_resume(struct xhci_hcd *xhci) 987 { 988 int ret = 0; 989 struct xhci_dbc *dbc = xhci->dbc; 990 991 if (!dbc) 992 return 0; 993 994 if (dbc->resume_required) { 995 dbc->resume_required = 0; 996 xhci_dbc_start(xhci); 997 } 998 999 return ret; 1000 } 1001 #endif /* CONFIG_PM */ 1002