1 // SPDX-License-Identifier: GPL-2.0 2 /** 3 * xhci-dbc.c - xHCI debug capability early driver 4 * 5 * Copyright (C) 2016 Intel Corporation 6 * 7 * Author: Lu Baolu <baolu.lu@linux.intel.com> 8 */ 9 10 #define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__ 11 12 #include <linux/console.h> 13 #include <linux/pci_regs.h> 14 #include <linux/pci_ids.h> 15 #include <linux/bootmem.h> 16 #include <linux/io.h> 17 #include <asm/pci-direct.h> 18 #include <asm/fixmap.h> 19 #include <linux/bcd.h> 20 #include <linux/export.h> 21 #include <linux/version.h> 22 #include <linux/module.h> 23 #include <linux/delay.h> 24 #include <linux/kthread.h> 25 26 #include "../host/xhci.h" 27 #include "xhci-dbc.h" 28 29 static struct xdbc_state xdbc; 30 static bool early_console_keep; 31 32 #ifdef XDBC_TRACE 33 #define xdbc_trace trace_printk 34 #else 35 static inline void xdbc_trace(const char *fmt, ...) { } 36 #endif /* XDBC_TRACE */ 37 38 static void __iomem * __init xdbc_map_pci_mmio(u32 bus, u32 dev, u32 func) 39 { 40 u64 val64, sz64, mask64; 41 void __iomem *base; 42 u32 val, sz; 43 u8 byte; 44 45 val = read_pci_config(bus, dev, func, PCI_BASE_ADDRESS_0); 46 write_pci_config(bus, dev, func, PCI_BASE_ADDRESS_0, ~0); 47 sz = read_pci_config(bus, dev, func, PCI_BASE_ADDRESS_0); 48 write_pci_config(bus, dev, func, PCI_BASE_ADDRESS_0, val); 49 50 if (val == 0xffffffff || sz == 0xffffffff) { 51 pr_notice("invalid mmio bar\n"); 52 return NULL; 53 } 54 55 val64 = val & PCI_BASE_ADDRESS_MEM_MASK; 56 sz64 = sz & PCI_BASE_ADDRESS_MEM_MASK; 57 mask64 = PCI_BASE_ADDRESS_MEM_MASK; 58 59 if ((val & PCI_BASE_ADDRESS_MEM_TYPE_MASK) == PCI_BASE_ADDRESS_MEM_TYPE_64) { 60 val = read_pci_config(bus, dev, func, PCI_BASE_ADDRESS_0 + 4); 61 write_pci_config(bus, dev, func, PCI_BASE_ADDRESS_0 + 4, ~0); 62 sz = read_pci_config(bus, dev, func, PCI_BASE_ADDRESS_0 + 4); 63 write_pci_config(bus, dev, func, PCI_BASE_ADDRESS_0 + 4, val); 64 65 val64 |= (u64)val << 32; 66 sz64 |= (u64)sz << 32; 67 mask64 |= ~0ULL << 32; 68 } 69 70 sz64 &= mask64; 71 72 if (!sz64) { 73 pr_notice("invalid mmio address\n"); 74 return NULL; 75 } 76 77 sz64 = 1ULL << __ffs64(sz64); 78 79 /* Check if the mem space is enabled: */ 80 byte = read_pci_config_byte(bus, dev, func, PCI_COMMAND); 81 if (!(byte & PCI_COMMAND_MEMORY)) { 82 byte |= PCI_COMMAND_MEMORY; 83 write_pci_config_byte(bus, dev, func, PCI_COMMAND, byte); 84 } 85 86 xdbc.xhci_start = val64; 87 xdbc.xhci_length = sz64; 88 base = early_ioremap(val64, sz64); 89 90 return base; 91 } 92 93 static void * __init xdbc_get_page(dma_addr_t *dma_addr) 94 { 95 void *virt; 96 97 virt = alloc_bootmem_pages_nopanic(PAGE_SIZE); 98 if (!virt) 99 return NULL; 100 101 if (dma_addr) 102 *dma_addr = (dma_addr_t)__pa(virt); 103 104 return virt; 105 } 106 107 static u32 __init xdbc_find_dbgp(int xdbc_num, u32 *b, u32 *d, u32 *f) 108 { 109 u32 bus, dev, func, class; 110 111 for (bus = 0; bus < XDBC_PCI_MAX_BUSES; bus++) { 112 for (dev = 0; dev < XDBC_PCI_MAX_DEVICES; dev++) { 113 for (func = 0; func < XDBC_PCI_MAX_FUNCTION; func++) { 114 115 class = read_pci_config(bus, dev, func, PCI_CLASS_REVISION); 116 if ((class >> 8) != PCI_CLASS_SERIAL_USB_XHCI) 117 continue; 118 119 if (xdbc_num-- != 0) 120 continue; 121 122 *b = bus; 123 *d = dev; 124 *f = func; 125 126 return 0; 127 } 128 } 129 } 130 131 return -1; 132 } 133 134 static int handshake(void __iomem *ptr, u32 mask, u32 done, int wait, int delay) 135 { 136 u32 result; 137 138 do { 139 result = readl(ptr); 140 result &= mask; 141 if (result == done) 142 return 0; 143 udelay(delay); 144 wait -= delay; 145 } while (wait > 0); 146 147 return -ETIMEDOUT; 148 } 149 150 static void __init xdbc_bios_handoff(void) 151 { 152 int offset, timeout; 153 u32 val; 154 155 offset = xhci_find_next_ext_cap(xdbc.xhci_base, 0, XHCI_EXT_CAPS_LEGACY); 156 val = readl(xdbc.xhci_base + offset); 157 158 if (val & XHCI_HC_BIOS_OWNED) { 159 writel(val | XHCI_HC_OS_OWNED, xdbc.xhci_base + offset); 160 timeout = handshake(xdbc.xhci_base + offset, XHCI_HC_BIOS_OWNED, 0, 5000, 10); 161 162 if (timeout) { 163 pr_notice("failed to hand over xHCI control from BIOS\n"); 164 writel(val & ~XHCI_HC_BIOS_OWNED, xdbc.xhci_base + offset); 165 } 166 } 167 168 /* Disable BIOS SMIs and clear all SMI events: */ 169 val = readl(xdbc.xhci_base + offset + XHCI_LEGACY_CONTROL_OFFSET); 170 val &= XHCI_LEGACY_DISABLE_SMI; 171 val |= XHCI_LEGACY_SMI_EVENTS; 172 writel(val, xdbc.xhci_base + offset + XHCI_LEGACY_CONTROL_OFFSET); 173 } 174 175 static int __init 176 xdbc_alloc_ring(struct xdbc_segment *seg, struct xdbc_ring *ring) 177 { 178 seg->trbs = xdbc_get_page(&seg->dma); 179 if (!seg->trbs) 180 return -ENOMEM; 181 182 ring->segment = seg; 183 184 return 0; 185 } 186 187 static void __init xdbc_free_ring(struct xdbc_ring *ring) 188 { 189 struct xdbc_segment *seg = ring->segment; 190 191 if (!seg) 192 return; 193 194 free_bootmem(seg->dma, PAGE_SIZE); 195 ring->segment = NULL; 196 } 197 198 static void xdbc_reset_ring(struct xdbc_ring *ring) 199 { 200 struct xdbc_segment *seg = ring->segment; 201 struct xdbc_trb *link_trb; 202 203 memset(seg->trbs, 0, PAGE_SIZE); 204 205 ring->enqueue = seg->trbs; 206 ring->dequeue = seg->trbs; 207 ring->cycle_state = 1; 208 209 if (ring != &xdbc.evt_ring) { 210 link_trb = &seg->trbs[XDBC_TRBS_PER_SEGMENT - 1]; 211 link_trb->field[0] = cpu_to_le32(lower_32_bits(seg->dma)); 212 link_trb->field[1] = cpu_to_le32(upper_32_bits(seg->dma)); 213 link_trb->field[3] = cpu_to_le32(TRB_TYPE(TRB_LINK)) | cpu_to_le32(LINK_TOGGLE); 214 } 215 } 216 217 static inline void xdbc_put_utf16(u16 *s, const char *c, size_t size) 218 { 219 int i; 220 221 for (i = 0; i < size; i++) 222 s[i] = cpu_to_le16(c[i]); 223 } 224 225 static void xdbc_mem_init(void) 226 { 227 struct xdbc_ep_context *ep_in, *ep_out; 228 struct usb_string_descriptor *s_desc; 229 struct xdbc_erst_entry *entry; 230 struct xdbc_strings *strings; 231 struct xdbc_context *ctx; 232 unsigned int max_burst; 233 u32 string_length; 234 int index = 0; 235 u32 dev_info; 236 237 xdbc_reset_ring(&xdbc.evt_ring); 238 xdbc_reset_ring(&xdbc.in_ring); 239 xdbc_reset_ring(&xdbc.out_ring); 240 memset(xdbc.table_base, 0, PAGE_SIZE); 241 memset(xdbc.out_buf, 0, PAGE_SIZE); 242 243 /* Initialize event ring segment table: */ 244 xdbc.erst_size = 16; 245 xdbc.erst_base = xdbc.table_base + index * XDBC_TABLE_ENTRY_SIZE; 246 xdbc.erst_dma = xdbc.table_dma + index * XDBC_TABLE_ENTRY_SIZE; 247 248 index += XDBC_ERST_ENTRY_NUM; 249 entry = (struct xdbc_erst_entry *)xdbc.erst_base; 250 251 entry->seg_addr = cpu_to_le64(xdbc.evt_seg.dma); 252 entry->seg_size = cpu_to_le32(XDBC_TRBS_PER_SEGMENT); 253 entry->__reserved_0 = 0; 254 255 /* Initialize ERST registers: */ 256 writel(1, &xdbc.xdbc_reg->ersts); 257 xdbc_write64(xdbc.erst_dma, &xdbc.xdbc_reg->erstba); 258 xdbc_write64(xdbc.evt_seg.dma, &xdbc.xdbc_reg->erdp); 259 260 /* Debug capability contexts: */ 261 xdbc.dbcc_size = 64 * 3; 262 xdbc.dbcc_base = xdbc.table_base + index * XDBC_TABLE_ENTRY_SIZE; 263 xdbc.dbcc_dma = xdbc.table_dma + index * XDBC_TABLE_ENTRY_SIZE; 264 265 index += XDBC_DBCC_ENTRY_NUM; 266 267 /* Popluate the strings: */ 268 xdbc.string_size = sizeof(struct xdbc_strings); 269 xdbc.string_base = xdbc.table_base + index * XDBC_TABLE_ENTRY_SIZE; 270 xdbc.string_dma = xdbc.table_dma + index * XDBC_TABLE_ENTRY_SIZE; 271 strings = (struct xdbc_strings *)xdbc.string_base; 272 273 index += XDBC_STRING_ENTRY_NUM; 274 275 /* Serial string: */ 276 s_desc = (struct usb_string_descriptor *)strings->serial; 277 s_desc->bLength = (strlen(XDBC_STRING_SERIAL) + 1) * 2; 278 s_desc->bDescriptorType = USB_DT_STRING; 279 280 xdbc_put_utf16(s_desc->wData, XDBC_STRING_SERIAL, strlen(XDBC_STRING_SERIAL)); 281 string_length = s_desc->bLength; 282 string_length <<= 8; 283 284 /* Product string: */ 285 s_desc = (struct usb_string_descriptor *)strings->product; 286 s_desc->bLength = (strlen(XDBC_STRING_PRODUCT) + 1) * 2; 287 s_desc->bDescriptorType = USB_DT_STRING; 288 289 xdbc_put_utf16(s_desc->wData, XDBC_STRING_PRODUCT, strlen(XDBC_STRING_PRODUCT)); 290 string_length += s_desc->bLength; 291 string_length <<= 8; 292 293 /* Manufacture string: */ 294 s_desc = (struct usb_string_descriptor *)strings->manufacturer; 295 s_desc->bLength = (strlen(XDBC_STRING_MANUFACTURER) + 1) * 2; 296 s_desc->bDescriptorType = USB_DT_STRING; 297 298 xdbc_put_utf16(s_desc->wData, XDBC_STRING_MANUFACTURER, strlen(XDBC_STRING_MANUFACTURER)); 299 string_length += s_desc->bLength; 300 string_length <<= 8; 301 302 /* String0: */ 303 strings->string0[0] = 4; 304 strings->string0[1] = USB_DT_STRING; 305 strings->string0[2] = 0x09; 306 strings->string0[3] = 0x04; 307 308 string_length += 4; 309 310 /* Populate info Context: */ 311 ctx = (struct xdbc_context *)xdbc.dbcc_base; 312 313 ctx->info.string0 = cpu_to_le64(xdbc.string_dma); 314 ctx->info.manufacturer = cpu_to_le64(xdbc.string_dma + XDBC_MAX_STRING_LENGTH); 315 ctx->info.product = cpu_to_le64(xdbc.string_dma + XDBC_MAX_STRING_LENGTH * 2); 316 ctx->info.serial = cpu_to_le64(xdbc.string_dma + XDBC_MAX_STRING_LENGTH * 3); 317 ctx->info.length = cpu_to_le32(string_length); 318 319 /* Populate bulk out endpoint context: */ 320 max_burst = DEBUG_MAX_BURST(readl(&xdbc.xdbc_reg->control)); 321 ep_out = (struct xdbc_ep_context *)&ctx->out; 322 323 ep_out->ep_info1 = 0; 324 ep_out->ep_info2 = cpu_to_le32(EP_TYPE(BULK_OUT_EP) | MAX_PACKET(1024) | MAX_BURST(max_burst)); 325 ep_out->deq = cpu_to_le64(xdbc.out_seg.dma | xdbc.out_ring.cycle_state); 326 327 /* Populate bulk in endpoint context: */ 328 ep_in = (struct xdbc_ep_context *)&ctx->in; 329 330 ep_in->ep_info1 = 0; 331 ep_in->ep_info2 = cpu_to_le32(EP_TYPE(BULK_IN_EP) | MAX_PACKET(1024) | MAX_BURST(max_burst)); 332 ep_in->deq = cpu_to_le64(xdbc.in_seg.dma | xdbc.in_ring.cycle_state); 333 334 /* Set DbC context and info registers: */ 335 xdbc_write64(xdbc.dbcc_dma, &xdbc.xdbc_reg->dccp); 336 337 dev_info = cpu_to_le32((XDBC_VENDOR_ID << 16) | XDBC_PROTOCOL); 338 writel(dev_info, &xdbc.xdbc_reg->devinfo1); 339 340 dev_info = cpu_to_le32((XDBC_DEVICE_REV << 16) | XDBC_PRODUCT_ID); 341 writel(dev_info, &xdbc.xdbc_reg->devinfo2); 342 343 xdbc.in_buf = xdbc.out_buf + XDBC_MAX_PACKET; 344 xdbc.in_dma = xdbc.out_dma + XDBC_MAX_PACKET; 345 } 346 347 static void xdbc_do_reset_debug_port(u32 id, u32 count) 348 { 349 void __iomem *ops_reg; 350 void __iomem *portsc; 351 u32 val, cap_length; 352 int i; 353 354 cap_length = readl(xdbc.xhci_base) & 0xff; 355 ops_reg = xdbc.xhci_base + cap_length; 356 357 id--; 358 for (i = id; i < (id + count); i++) { 359 portsc = ops_reg + 0x400 + i * 0x10; 360 val = readl(portsc); 361 if (!(val & PORT_CONNECT)) 362 writel(val | PORT_RESET, portsc); 363 } 364 } 365 366 static void xdbc_reset_debug_port(void) 367 { 368 u32 val, port_offset, port_count; 369 int offset = 0; 370 371 do { 372 offset = xhci_find_next_ext_cap(xdbc.xhci_base, offset, XHCI_EXT_CAPS_PROTOCOL); 373 if (!offset) 374 break; 375 376 val = readl(xdbc.xhci_base + offset); 377 if (XHCI_EXT_PORT_MAJOR(val) != 0x3) 378 continue; 379 380 val = readl(xdbc.xhci_base + offset + 8); 381 port_offset = XHCI_EXT_PORT_OFF(val); 382 port_count = XHCI_EXT_PORT_COUNT(val); 383 384 xdbc_do_reset_debug_port(port_offset, port_count); 385 } while (1); 386 } 387 388 static void 389 xdbc_queue_trb(struct xdbc_ring *ring, u32 field1, u32 field2, u32 field3, u32 field4) 390 { 391 struct xdbc_trb *trb, *link_trb; 392 393 trb = ring->enqueue; 394 trb->field[0] = cpu_to_le32(field1); 395 trb->field[1] = cpu_to_le32(field2); 396 trb->field[2] = cpu_to_le32(field3); 397 trb->field[3] = cpu_to_le32(field4); 398 399 ++(ring->enqueue); 400 if (ring->enqueue >= &ring->segment->trbs[TRBS_PER_SEGMENT - 1]) { 401 link_trb = ring->enqueue; 402 if (ring->cycle_state) 403 link_trb->field[3] |= cpu_to_le32(TRB_CYCLE); 404 else 405 link_trb->field[3] &= cpu_to_le32(~TRB_CYCLE); 406 407 ring->enqueue = ring->segment->trbs; 408 ring->cycle_state ^= 1; 409 } 410 } 411 412 static void xdbc_ring_doorbell(int target) 413 { 414 writel(DOOR_BELL_TARGET(target), &xdbc.xdbc_reg->doorbell); 415 } 416 417 static int xdbc_start(void) 418 { 419 u32 ctrl, status; 420 int ret; 421 422 ctrl = readl(&xdbc.xdbc_reg->control); 423 writel(ctrl | CTRL_DBC_ENABLE | CTRL_PORT_ENABLE, &xdbc.xdbc_reg->control); 424 ret = handshake(&xdbc.xdbc_reg->control, CTRL_DBC_ENABLE, CTRL_DBC_ENABLE, 100000, 100); 425 if (ret) { 426 xdbc_trace("failed to initialize hardware\n"); 427 return ret; 428 } 429 430 /* Reset port to avoid bus hang: */ 431 if (xdbc.vendor == PCI_VENDOR_ID_INTEL) 432 xdbc_reset_debug_port(); 433 434 /* Wait for port connection: */ 435 ret = handshake(&xdbc.xdbc_reg->portsc, PORTSC_CONN_STATUS, PORTSC_CONN_STATUS, 5000000, 100); 436 if (ret) { 437 xdbc_trace("waiting for connection timed out\n"); 438 return ret; 439 } 440 441 /* Wait for debug device to be configured: */ 442 ret = handshake(&xdbc.xdbc_reg->control, CTRL_DBC_RUN, CTRL_DBC_RUN, 5000000, 100); 443 if (ret) { 444 xdbc_trace("waiting for device configuration timed out\n"); 445 return ret; 446 } 447 448 /* Check port number: */ 449 status = readl(&xdbc.xdbc_reg->status); 450 if (!DCST_DEBUG_PORT(status)) { 451 xdbc_trace("invalid root hub port number\n"); 452 return -ENODEV; 453 } 454 455 xdbc.port_number = DCST_DEBUG_PORT(status); 456 457 xdbc_trace("DbC is running now, control 0x%08x port ID %d\n", 458 readl(&xdbc.xdbc_reg->control), xdbc.port_number); 459 460 return 0; 461 } 462 463 static int xdbc_bulk_transfer(void *data, int size, bool read) 464 { 465 struct xdbc_ring *ring; 466 struct xdbc_trb *trb; 467 u32 length, control; 468 u32 cycle; 469 u64 addr; 470 471 if (size > XDBC_MAX_PACKET) { 472 xdbc_trace("bad parameter, size %d\n", size); 473 return -EINVAL; 474 } 475 476 if (!(xdbc.flags & XDBC_FLAGS_INITIALIZED) || 477 !(xdbc.flags & XDBC_FLAGS_CONFIGURED) || 478 (!read && (xdbc.flags & XDBC_FLAGS_OUT_STALL)) || 479 (read && (xdbc.flags & XDBC_FLAGS_IN_STALL))) { 480 481 xdbc_trace("connection not ready, flags %08x\n", xdbc.flags); 482 return -EIO; 483 } 484 485 ring = (read ? &xdbc.in_ring : &xdbc.out_ring); 486 trb = ring->enqueue; 487 cycle = ring->cycle_state; 488 length = TRB_LEN(size); 489 control = TRB_TYPE(TRB_NORMAL) | TRB_IOC; 490 491 if (cycle) 492 control &= cpu_to_le32(~TRB_CYCLE); 493 else 494 control |= cpu_to_le32(TRB_CYCLE); 495 496 if (read) { 497 memset(xdbc.in_buf, 0, XDBC_MAX_PACKET); 498 addr = xdbc.in_dma; 499 xdbc.flags |= XDBC_FLAGS_IN_PROCESS; 500 } else { 501 memset(xdbc.out_buf, 0, XDBC_MAX_PACKET); 502 memcpy(xdbc.out_buf, data, size); 503 addr = xdbc.out_dma; 504 xdbc.flags |= XDBC_FLAGS_OUT_PROCESS; 505 } 506 507 xdbc_queue_trb(ring, lower_32_bits(addr), upper_32_bits(addr), length, control); 508 509 /* 510 * Add a barrier between writes of trb fields and flipping 511 * the cycle bit: 512 */ 513 wmb(); 514 if (cycle) 515 trb->field[3] |= cpu_to_le32(cycle); 516 else 517 trb->field[3] &= cpu_to_le32(~TRB_CYCLE); 518 519 xdbc_ring_doorbell(read ? IN_EP_DOORBELL : OUT_EP_DOORBELL); 520 521 return size; 522 } 523 524 static int xdbc_handle_external_reset(void) 525 { 526 int ret = 0; 527 528 xdbc.flags = 0; 529 writel(0, &xdbc.xdbc_reg->control); 530 ret = handshake(&xdbc.xdbc_reg->control, CTRL_DBC_ENABLE, 0, 100000, 10); 531 if (ret) 532 goto reset_out; 533 534 xdbc_mem_init(); 535 536 mmiowb(); 537 538 ret = xdbc_start(); 539 if (ret < 0) 540 goto reset_out; 541 542 xdbc_trace("dbc recovered\n"); 543 544 xdbc.flags |= XDBC_FLAGS_INITIALIZED | XDBC_FLAGS_CONFIGURED; 545 546 xdbc_bulk_transfer(NULL, XDBC_MAX_PACKET, true); 547 548 return 0; 549 550 reset_out: 551 xdbc_trace("failed to recover from external reset\n"); 552 return ret; 553 } 554 555 static int __init xdbc_early_setup(void) 556 { 557 int ret; 558 559 writel(0, &xdbc.xdbc_reg->control); 560 ret = handshake(&xdbc.xdbc_reg->control, CTRL_DBC_ENABLE, 0, 100000, 100); 561 if (ret) 562 return ret; 563 564 /* Allocate the table page: */ 565 xdbc.table_base = xdbc_get_page(&xdbc.table_dma); 566 if (!xdbc.table_base) 567 return -ENOMEM; 568 569 /* Get and store the transfer buffer: */ 570 xdbc.out_buf = xdbc_get_page(&xdbc.out_dma); 571 if (!xdbc.out_buf) 572 return -ENOMEM; 573 574 /* Allocate the event ring: */ 575 ret = xdbc_alloc_ring(&xdbc.evt_seg, &xdbc.evt_ring); 576 if (ret < 0) 577 return ret; 578 579 /* Allocate IN/OUT endpoint transfer rings: */ 580 ret = xdbc_alloc_ring(&xdbc.in_seg, &xdbc.in_ring); 581 if (ret < 0) 582 return ret; 583 584 ret = xdbc_alloc_ring(&xdbc.out_seg, &xdbc.out_ring); 585 if (ret < 0) 586 return ret; 587 588 xdbc_mem_init(); 589 590 mmiowb(); 591 592 ret = xdbc_start(); 593 if (ret < 0) { 594 writel(0, &xdbc.xdbc_reg->control); 595 return ret; 596 } 597 598 xdbc.flags |= XDBC_FLAGS_INITIALIZED | XDBC_FLAGS_CONFIGURED; 599 600 xdbc_bulk_transfer(NULL, XDBC_MAX_PACKET, true); 601 602 return 0; 603 } 604 605 int __init early_xdbc_parse_parameter(char *s) 606 { 607 unsigned long dbgp_num = 0; 608 u32 bus, dev, func, offset; 609 int ret; 610 611 if (!early_pci_allowed()) 612 return -EPERM; 613 614 if (strstr(s, "keep")) 615 early_console_keep = true; 616 617 if (xdbc.xdbc_reg) 618 return 0; 619 620 if (*s && kstrtoul(s, 0, &dbgp_num)) 621 dbgp_num = 0; 622 623 pr_notice("dbgp_num: %lu\n", dbgp_num); 624 625 /* Locate the host controller: */ 626 ret = xdbc_find_dbgp(dbgp_num, &bus, &dev, &func); 627 if (ret) { 628 pr_notice("failed to locate xhci host\n"); 629 return -ENODEV; 630 } 631 632 xdbc.vendor = read_pci_config_16(bus, dev, func, PCI_VENDOR_ID); 633 xdbc.device = read_pci_config_16(bus, dev, func, PCI_DEVICE_ID); 634 xdbc.bus = bus; 635 xdbc.dev = dev; 636 xdbc.func = func; 637 638 /* Map the IO memory: */ 639 xdbc.xhci_base = xdbc_map_pci_mmio(bus, dev, func); 640 if (!xdbc.xhci_base) 641 return -EINVAL; 642 643 /* Locate DbC registers: */ 644 offset = xhci_find_next_ext_cap(xdbc.xhci_base, 0, XHCI_EXT_CAPS_DEBUG); 645 if (!offset) { 646 pr_notice("xhci host doesn't support debug capability\n"); 647 early_iounmap(xdbc.xhci_base, xdbc.xhci_length); 648 xdbc.xhci_base = NULL; 649 xdbc.xhci_length = 0; 650 651 return -ENODEV; 652 } 653 xdbc.xdbc_reg = (struct xdbc_regs __iomem *)(xdbc.xhci_base + offset); 654 655 return 0; 656 } 657 658 int __init early_xdbc_setup_hardware(void) 659 { 660 int ret; 661 662 if (!xdbc.xdbc_reg) 663 return -ENODEV; 664 665 xdbc_bios_handoff(); 666 667 raw_spin_lock_init(&xdbc.lock); 668 669 ret = xdbc_early_setup(); 670 if (ret) { 671 pr_notice("failed to setup the connection to host\n"); 672 673 xdbc_free_ring(&xdbc.evt_ring); 674 xdbc_free_ring(&xdbc.out_ring); 675 xdbc_free_ring(&xdbc.in_ring); 676 677 if (xdbc.table_dma) 678 free_bootmem(xdbc.table_dma, PAGE_SIZE); 679 680 if (xdbc.out_dma) 681 free_bootmem(xdbc.out_dma, PAGE_SIZE); 682 683 xdbc.table_base = NULL; 684 xdbc.out_buf = NULL; 685 } 686 687 return ret; 688 } 689 690 static void xdbc_handle_port_status(struct xdbc_trb *evt_trb) 691 { 692 u32 port_reg; 693 694 port_reg = readl(&xdbc.xdbc_reg->portsc); 695 if (port_reg & PORTSC_CONN_CHANGE) { 696 xdbc_trace("connect status change event\n"); 697 698 /* Check whether cable unplugged: */ 699 if (!(port_reg & PORTSC_CONN_STATUS)) { 700 xdbc.flags = 0; 701 xdbc_trace("cable unplugged\n"); 702 } 703 } 704 705 if (port_reg & PORTSC_RESET_CHANGE) 706 xdbc_trace("port reset change event\n"); 707 708 if (port_reg & PORTSC_LINK_CHANGE) 709 xdbc_trace("port link status change event\n"); 710 711 if (port_reg & PORTSC_CONFIG_CHANGE) 712 xdbc_trace("config error change\n"); 713 714 /* Write back the value to clear RW1C bits: */ 715 writel(port_reg, &xdbc.xdbc_reg->portsc); 716 } 717 718 static void xdbc_handle_tx_event(struct xdbc_trb *evt_trb) 719 { 720 size_t remain_length; 721 u32 comp_code; 722 int ep_id; 723 724 comp_code = GET_COMP_CODE(le32_to_cpu(evt_trb->field[2])); 725 remain_length = EVENT_TRB_LEN(le32_to_cpu(evt_trb->field[2])); 726 ep_id = TRB_TO_EP_ID(le32_to_cpu(evt_trb->field[3])); 727 728 switch (comp_code) { 729 case COMP_SUCCESS: 730 remain_length = 0; 731 case COMP_SHORT_PACKET: 732 break; 733 case COMP_TRB_ERROR: 734 case COMP_BABBLE_DETECTED_ERROR: 735 case COMP_USB_TRANSACTION_ERROR: 736 case COMP_STALL_ERROR: 737 default: 738 if (ep_id == XDBC_EPID_OUT) 739 xdbc.flags |= XDBC_FLAGS_OUT_STALL; 740 if (ep_id == XDBC_EPID_IN) 741 xdbc.flags |= XDBC_FLAGS_IN_STALL; 742 743 xdbc_trace("endpoint %d stalled\n", ep_id); 744 break; 745 } 746 747 if (ep_id == XDBC_EPID_IN) { 748 xdbc.flags &= ~XDBC_FLAGS_IN_PROCESS; 749 xdbc_bulk_transfer(NULL, XDBC_MAX_PACKET, true); 750 } else if (ep_id == XDBC_EPID_OUT) { 751 xdbc.flags &= ~XDBC_FLAGS_OUT_PROCESS; 752 } else { 753 xdbc_trace("invalid endpoint id %d\n", ep_id); 754 } 755 } 756 757 static void xdbc_handle_events(void) 758 { 759 struct xdbc_trb *evt_trb; 760 bool update_erdp = false; 761 u32 reg; 762 u8 cmd; 763 764 cmd = read_pci_config_byte(xdbc.bus, xdbc.dev, xdbc.func, PCI_COMMAND); 765 if (!(cmd & PCI_COMMAND_MASTER)) { 766 cmd |= PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY; 767 write_pci_config_byte(xdbc.bus, xdbc.dev, xdbc.func, PCI_COMMAND, cmd); 768 } 769 770 if (!(xdbc.flags & XDBC_FLAGS_INITIALIZED)) 771 return; 772 773 /* Handle external reset events: */ 774 reg = readl(&xdbc.xdbc_reg->control); 775 if (!(reg & CTRL_DBC_ENABLE)) { 776 if (xdbc_handle_external_reset()) { 777 xdbc_trace("failed to recover connection\n"); 778 return; 779 } 780 } 781 782 /* Handle configure-exit event: */ 783 reg = readl(&xdbc.xdbc_reg->control); 784 if (reg & CTRL_DBC_RUN_CHANGE) { 785 writel(reg, &xdbc.xdbc_reg->control); 786 if (reg & CTRL_DBC_RUN) 787 xdbc.flags |= XDBC_FLAGS_CONFIGURED; 788 else 789 xdbc.flags &= ~XDBC_FLAGS_CONFIGURED; 790 } 791 792 /* Handle endpoint stall event: */ 793 reg = readl(&xdbc.xdbc_reg->control); 794 if (reg & CTRL_HALT_IN_TR) { 795 xdbc.flags |= XDBC_FLAGS_IN_STALL; 796 } else { 797 xdbc.flags &= ~XDBC_FLAGS_IN_STALL; 798 if (!(xdbc.flags & XDBC_FLAGS_IN_PROCESS)) 799 xdbc_bulk_transfer(NULL, XDBC_MAX_PACKET, true); 800 } 801 802 if (reg & CTRL_HALT_OUT_TR) 803 xdbc.flags |= XDBC_FLAGS_OUT_STALL; 804 else 805 xdbc.flags &= ~XDBC_FLAGS_OUT_STALL; 806 807 /* Handle the events in the event ring: */ 808 evt_trb = xdbc.evt_ring.dequeue; 809 while ((le32_to_cpu(evt_trb->field[3]) & TRB_CYCLE) == xdbc.evt_ring.cycle_state) { 810 /* 811 * Add a barrier between reading the cycle flag and any 812 * reads of the event's flags/data below: 813 */ 814 rmb(); 815 816 switch ((le32_to_cpu(evt_trb->field[3]) & TRB_TYPE_BITMASK)) { 817 case TRB_TYPE(TRB_PORT_STATUS): 818 xdbc_handle_port_status(evt_trb); 819 break; 820 case TRB_TYPE(TRB_TRANSFER): 821 xdbc_handle_tx_event(evt_trb); 822 break; 823 default: 824 break; 825 } 826 827 ++(xdbc.evt_ring.dequeue); 828 if (xdbc.evt_ring.dequeue == &xdbc.evt_seg.trbs[TRBS_PER_SEGMENT]) { 829 xdbc.evt_ring.dequeue = xdbc.evt_seg.trbs; 830 xdbc.evt_ring.cycle_state ^= 1; 831 } 832 833 evt_trb = xdbc.evt_ring.dequeue; 834 update_erdp = true; 835 } 836 837 /* Update event ring dequeue pointer: */ 838 if (update_erdp) 839 xdbc_write64(__pa(xdbc.evt_ring.dequeue), &xdbc.xdbc_reg->erdp); 840 } 841 842 static int xdbc_bulk_write(const char *bytes, int size) 843 { 844 int ret, timeout = 0; 845 unsigned long flags; 846 847 retry: 848 if (in_nmi()) { 849 if (!raw_spin_trylock_irqsave(&xdbc.lock, flags)) 850 return -EAGAIN; 851 } else { 852 raw_spin_lock_irqsave(&xdbc.lock, flags); 853 } 854 855 xdbc_handle_events(); 856 857 /* Check completion of the previous request: */ 858 if ((xdbc.flags & XDBC_FLAGS_OUT_PROCESS) && (timeout < 2000000)) { 859 raw_spin_unlock_irqrestore(&xdbc.lock, flags); 860 udelay(100); 861 timeout += 100; 862 goto retry; 863 } 864 865 if (xdbc.flags & XDBC_FLAGS_OUT_PROCESS) { 866 raw_spin_unlock_irqrestore(&xdbc.lock, flags); 867 xdbc_trace("previous transfer not completed yet\n"); 868 869 return -ETIMEDOUT; 870 } 871 872 ret = xdbc_bulk_transfer((void *)bytes, size, false); 873 raw_spin_unlock_irqrestore(&xdbc.lock, flags); 874 875 return ret; 876 } 877 878 static void early_xdbc_write(struct console *con, const char *str, u32 n) 879 { 880 static char buf[XDBC_MAX_PACKET]; 881 int chunk, ret; 882 int use_cr = 0; 883 884 if (!xdbc.xdbc_reg) 885 return; 886 memset(buf, 0, XDBC_MAX_PACKET); 887 while (n > 0) { 888 for (chunk = 0; chunk < XDBC_MAX_PACKET && n > 0; str++, chunk++, n--) { 889 890 if (!use_cr && *str == '\n') { 891 use_cr = 1; 892 buf[chunk] = '\r'; 893 str--; 894 n++; 895 continue; 896 } 897 898 if (use_cr) 899 use_cr = 0; 900 buf[chunk] = *str; 901 } 902 903 if (chunk > 0) { 904 ret = xdbc_bulk_write(buf, chunk); 905 if (ret < 0) 906 xdbc_trace("missed message {%s}\n", buf); 907 } 908 } 909 } 910 911 static struct console early_xdbc_console = { 912 .name = "earlyxdbc", 913 .write = early_xdbc_write, 914 .flags = CON_PRINTBUFFER, 915 .index = -1, 916 }; 917 918 void __init early_xdbc_register_console(void) 919 { 920 if (early_console) 921 return; 922 923 early_console = &early_xdbc_console; 924 if (early_console_keep) 925 early_console->flags &= ~CON_BOOT; 926 else 927 early_console->flags |= CON_BOOT; 928 register_console(early_console); 929 } 930 931 static void xdbc_unregister_console(void) 932 { 933 if (early_xdbc_console.flags & CON_ENABLED) 934 unregister_console(&early_xdbc_console); 935 } 936 937 static int xdbc_scrub_function(void *ptr) 938 { 939 unsigned long flags; 940 941 while (true) { 942 raw_spin_lock_irqsave(&xdbc.lock, flags); 943 xdbc_handle_events(); 944 945 if (!(xdbc.flags & XDBC_FLAGS_INITIALIZED)) { 946 raw_spin_unlock_irqrestore(&xdbc.lock, flags); 947 break; 948 } 949 950 raw_spin_unlock_irqrestore(&xdbc.lock, flags); 951 schedule_timeout_interruptible(1); 952 } 953 954 xdbc_unregister_console(); 955 writel(0, &xdbc.xdbc_reg->control); 956 xdbc_trace("dbc scrub function exits\n"); 957 958 return 0; 959 } 960 961 static int __init xdbc_init(void) 962 { 963 unsigned long flags; 964 void __iomem *base; 965 int ret = 0; 966 u32 offset; 967 968 if (!(xdbc.flags & XDBC_FLAGS_INITIALIZED)) 969 return 0; 970 971 /* 972 * It's time to shut down the DbC, so that the debug 973 * port can be reused by the host controller: 974 */ 975 if (early_xdbc_console.index == -1 || 976 (early_xdbc_console.flags & CON_BOOT)) { 977 xdbc_trace("hardware not used anymore\n"); 978 goto free_and_quit; 979 } 980 981 base = ioremap_nocache(xdbc.xhci_start, xdbc.xhci_length); 982 if (!base) { 983 xdbc_trace("failed to remap the io address\n"); 984 ret = -ENOMEM; 985 goto free_and_quit; 986 } 987 988 raw_spin_lock_irqsave(&xdbc.lock, flags); 989 early_iounmap(xdbc.xhci_base, xdbc.xhci_length); 990 xdbc.xhci_base = base; 991 offset = xhci_find_next_ext_cap(xdbc.xhci_base, 0, XHCI_EXT_CAPS_DEBUG); 992 xdbc.xdbc_reg = (struct xdbc_regs __iomem *)(xdbc.xhci_base + offset); 993 raw_spin_unlock_irqrestore(&xdbc.lock, flags); 994 995 kthread_run(xdbc_scrub_function, NULL, "%s", "xdbc"); 996 997 return 0; 998 999 free_and_quit: 1000 xdbc_free_ring(&xdbc.evt_ring); 1001 xdbc_free_ring(&xdbc.out_ring); 1002 xdbc_free_ring(&xdbc.in_ring); 1003 free_bootmem(xdbc.table_dma, PAGE_SIZE); 1004 free_bootmem(xdbc.out_dma, PAGE_SIZE); 1005 writel(0, &xdbc.xdbc_reg->control); 1006 early_iounmap(xdbc.xhci_base, xdbc.xhci_length); 1007 1008 return ret; 1009 } 1010 subsys_initcall(xdbc_init); 1011