1/* 2 * Standalone EHCI usb debug driver 3 * 4 * Originally written by: 5 * Eric W. Biederman" <ebiederm@xmission.com> and 6 * Yinghai Lu <yhlu.kernel@gmail.com> 7 * 8 * Changes for early/late printk and HW errata: 9 * Jason Wessel <jason.wessel@windriver.com> 10 * Copyright (C) 2009 Wind River Systems, Inc. 11 * 12 */ 13 14#include <linux/console.h> 15#include <linux/errno.h> 16#include <linux/module.h> 17#include <linux/pci_regs.h> 18#include <linux/pci_ids.h> 19#include <linux/usb/ch9.h> 20#include <linux/usb/ehci_def.h> 21#include <linux/delay.h> 22#include <linux/serial_core.h> 23#include <linux/kgdb.h> 24#include <linux/kthread.h> 25#include <asm/io.h> 26#include <asm/pci-direct.h> 27#include <asm/fixmap.h> 28 29/* The code here is intended to talk directly to the EHCI debug port 30 * and does not require that you have any kind of USB host controller 31 * drivers or USB device drivers compiled into the kernel. 32 * 33 * If you make a change to anything in here, the following test cases 34 * need to pass where a USB debug device works in the following 35 * configurations. 36 * 37 * 1. boot args: earlyprintk=dbgp 38 * o kernel compiled with # CONFIG_USB_EHCI_HCD is not set 39 * o kernel compiled with CONFIG_USB_EHCI_HCD=y 40 * 2. boot args: earlyprintk=dbgp,keep 41 * o kernel compiled with # CONFIG_USB_EHCI_HCD is not set 42 * o kernel compiled with CONFIG_USB_EHCI_HCD=y 43 * 3. boot args: earlyprintk=dbgp console=ttyUSB0 44 * o kernel has CONFIG_USB_EHCI_HCD=y and 45 * CONFIG_USB_SERIAL_DEBUG=y 46 * 4. boot args: earlyprintk=vga,dbgp 47 * o kernel compiled with # CONFIG_USB_EHCI_HCD is not set 48 * o kernel compiled with CONFIG_USB_EHCI_HCD=y 49 * 50 * For the 4th configuration you can turn on or off the DBGP_DEBUG 51 * such that you can debug the dbgp device's driver code. 52 */ 53 54static int dbgp_phys_port = 1; 55 56static struct ehci_caps __iomem *ehci_caps; 57static struct ehci_regs __iomem *ehci_regs; 58static struct ehci_dbg_port __iomem *ehci_debug; 59static int dbgp_not_safe; /* Cannot use debug device during ehci reset */ 60static unsigned int dbgp_endpoint_out; 61static unsigned int dbgp_endpoint_in; 62 63struct ehci_dev { 64 u32 bus; 65 u32 slot; 66 u32 func; 67}; 68 69static struct ehci_dev ehci_dev; 70 71#define USB_DEBUG_DEVNUM 127 72 73#ifdef DBGP_DEBUG 74#define dbgp_printk printk 75static void dbgp_ehci_status(char *str) 76{ 77 if (!ehci_debug) 78 return; 79 dbgp_printk("dbgp: %s\n", str); 80 dbgp_printk(" Debug control: %08x", readl(&ehci_debug->control)); 81 dbgp_printk(" ehci cmd : %08x", readl(&ehci_regs->command)); 82 dbgp_printk(" ehci conf flg: %08x\n", 83 readl(&ehci_regs->configured_flag)); 84 dbgp_printk(" ehci status : %08x", readl(&ehci_regs->status)); 85 dbgp_printk(" ehci portsc : %08x\n", 86 readl(&ehci_regs->port_status[dbgp_phys_port - 1])); 87} 88#else 89static inline void dbgp_ehci_status(char *str) { } 90static inline void dbgp_printk(const char *fmt, ...) { } 91#endif 92 93static inline u32 dbgp_len_update(u32 x, u32 len) 94{ 95 return (x & ~0x0f) | (len & 0x0f); 96} 97 98#ifdef CONFIG_KGDB 99static struct kgdb_io kgdbdbgp_io_ops; 100#define dbgp_kgdb_mode (dbg_io_ops == &kgdbdbgp_io_ops) 101#else 102#define dbgp_kgdb_mode (0) 103#endif 104 105/* 106 * USB Packet IDs (PIDs) 107 */ 108 109/* token */ 110#define USB_PID_OUT 0xe1 111#define USB_PID_IN 0x69 112#define USB_PID_SOF 0xa5 113#define USB_PID_SETUP 0x2d 114/* handshake */ 115#define USB_PID_ACK 0xd2 116#define USB_PID_NAK 0x5a 117#define USB_PID_STALL 0x1e 118#define USB_PID_NYET 0x96 119/* data */ 120#define USB_PID_DATA0 0xc3 121#define USB_PID_DATA1 0x4b 122#define USB_PID_DATA2 0x87 123#define USB_PID_MDATA 0x0f 124/* Special */ 125#define USB_PID_PREAMBLE 0x3c 126#define USB_PID_ERR 0x3c 127#define USB_PID_SPLIT 0x78 128#define USB_PID_PING 0xb4 129#define USB_PID_UNDEF_0 0xf0 130 131#define USB_PID_DATA_TOGGLE 0x88 132#define DBGP_CLAIM (DBGP_OWNER | DBGP_ENABLED | DBGP_INUSE) 133 134#define PCI_CAP_ID_EHCI_DEBUG 0xa 135 136#define HUB_ROOT_RESET_TIME 50 /* times are in msec */ 137#define HUB_SHORT_RESET_TIME 10 138#define HUB_LONG_RESET_TIME 200 139#define HUB_RESET_TIMEOUT 500 140 141#define DBGP_MAX_PACKET 8 142#define DBGP_TIMEOUT (250 * 1000) 143#define DBGP_LOOPS 1000 144 145static inline u32 dbgp_pid_write_update(u32 x, u32 tok) 146{ 147 static int data0 = USB_PID_DATA1; 148 data0 ^= USB_PID_DATA_TOGGLE; 149 return (x & 0xffff0000) | (data0 << 8) | (tok & 0xff); 150} 151 152static inline u32 dbgp_pid_read_update(u32 x, u32 tok) 153{ 154 return (x & 0xffff0000) | (USB_PID_DATA0 << 8) | (tok & 0xff); 155} 156 157static int dbgp_wait_until_complete(void) 158{ 159 u32 ctrl; 160 int loop = DBGP_TIMEOUT; 161 162 do { 163 ctrl = readl(&ehci_debug->control); 164 /* Stop when the transaction is finished */ 165 if (ctrl & DBGP_DONE) 166 break; 167 udelay(1); 168 } while (--loop > 0); 169 170 if (!loop) 171 return -DBGP_TIMEOUT; 172 173 /* 174 * Now that we have observed the completed transaction, 175 * clear the done bit. 176 */ 177 writel(ctrl | DBGP_DONE, &ehci_debug->control); 178 return (ctrl & DBGP_ERROR) ? -DBGP_ERRCODE(ctrl) : DBGP_LEN(ctrl); 179} 180 181static inline void dbgp_mdelay(int ms) 182{ 183 int i; 184 185 while (ms--) { 186 for (i = 0; i < 1000; i++) 187 outb(0x1, 0x80); 188 } 189} 190 191static void dbgp_breath(void) 192{ 193 /* Sleep to give the debug port a chance to breathe */ 194} 195 196static int dbgp_wait_until_done(unsigned ctrl, int loop) 197{ 198 u32 pids, lpid; 199 int ret; 200 201retry: 202 writel(ctrl | DBGP_GO, &ehci_debug->control); 203 ret = dbgp_wait_until_complete(); 204 pids = readl(&ehci_debug->pids); 205 lpid = DBGP_PID_GET(pids); 206 207 if (ret < 0) { 208 /* A -DBGP_TIMEOUT failure here means the device has 209 * failed, perhaps because it was unplugged, in which 210 * case we do not want to hang the system so the dbgp 211 * will be marked as unsafe to use. EHCI reset is the 212 * only way to recover if you unplug the dbgp device. 213 */ 214 if (ret == -DBGP_TIMEOUT && !dbgp_not_safe) 215 dbgp_not_safe = 1; 216 if (ret == -DBGP_ERR_BAD && --loop > 0) 217 goto retry; 218 return ret; 219 } 220 221 /* 222 * If the port is getting full or it has dropped data 223 * start pacing ourselves, not necessary but it's friendly. 224 */ 225 if ((lpid == USB_PID_NAK) || (lpid == USB_PID_NYET)) 226 dbgp_breath(); 227 228 /* If I get a NACK reissue the transmission */ 229 if (lpid == USB_PID_NAK) { 230 if (--loop > 0) 231 goto retry; 232 } 233 234 return ret; 235} 236 237static inline void dbgp_set_data(const void *buf, int size) 238{ 239 const unsigned char *bytes = buf; 240 u32 lo, hi; 241 int i; 242 243 lo = hi = 0; 244 for (i = 0; i < 4 && i < size; i++) 245 lo |= bytes[i] << (8*i); 246 for (; i < 8 && i < size; i++) 247 hi |= bytes[i] << (8*(i - 4)); 248 writel(lo, &ehci_debug->data03); 249 writel(hi, &ehci_debug->data47); 250} 251 252static inline void dbgp_get_data(void *buf, int size) 253{ 254 unsigned char *bytes = buf; 255 u32 lo, hi; 256 int i; 257 258 lo = readl(&ehci_debug->data03); 259 hi = readl(&ehci_debug->data47); 260 for (i = 0; i < 4 && i < size; i++) 261 bytes[i] = (lo >> (8*i)) & 0xff; 262 for (; i < 8 && i < size; i++) 263 bytes[i] = (hi >> (8*(i - 4))) & 0xff; 264} 265 266static int dbgp_bulk_write(unsigned devnum, unsigned endpoint, 267 const char *bytes, int size) 268{ 269 int ret; 270 u32 addr; 271 u32 pids, ctrl; 272 273 if (size > DBGP_MAX_PACKET) 274 return -1; 275 276 addr = DBGP_EPADDR(devnum, endpoint); 277 278 pids = readl(&ehci_debug->pids); 279 pids = dbgp_pid_write_update(pids, USB_PID_OUT); 280 281 ctrl = readl(&ehci_debug->control); 282 ctrl = dbgp_len_update(ctrl, size); 283 ctrl |= DBGP_OUT; 284 ctrl |= DBGP_GO; 285 286 dbgp_set_data(bytes, size); 287 writel(addr, &ehci_debug->address); 288 writel(pids, &ehci_debug->pids); 289 ret = dbgp_wait_until_done(ctrl, DBGP_LOOPS); 290 291 return ret; 292} 293 294static int dbgp_bulk_read(unsigned devnum, unsigned endpoint, void *data, 295 int size, int loops) 296{ 297 u32 pids, addr, ctrl; 298 int ret; 299 300 if (size > DBGP_MAX_PACKET) 301 return -1; 302 303 addr = DBGP_EPADDR(devnum, endpoint); 304 305 pids = readl(&ehci_debug->pids); 306 pids = dbgp_pid_read_update(pids, USB_PID_IN); 307 308 ctrl = readl(&ehci_debug->control); 309 ctrl = dbgp_len_update(ctrl, size); 310 ctrl &= ~DBGP_OUT; 311 ctrl |= DBGP_GO; 312 313 writel(addr, &ehci_debug->address); 314 writel(pids, &ehci_debug->pids); 315 ret = dbgp_wait_until_done(ctrl, loops); 316 if (ret < 0) 317 return ret; 318 319 if (size > ret) 320 size = ret; 321 dbgp_get_data(data, size); 322 return ret; 323} 324 325static int dbgp_control_msg(unsigned devnum, int requesttype, 326 int request, int value, int index, void *data, int size) 327{ 328 u32 pids, addr, ctrl; 329 struct usb_ctrlrequest req; 330 int read; 331 int ret; 332 333 read = (requesttype & USB_DIR_IN) != 0; 334 if (size > (read ? DBGP_MAX_PACKET:0)) 335 return -1; 336 337 /* Compute the control message */ 338 req.bRequestType = requesttype; 339 req.bRequest = request; 340 req.wValue = cpu_to_le16(value); 341 req.wIndex = cpu_to_le16(index); 342 req.wLength = cpu_to_le16(size); 343 344 pids = DBGP_PID_SET(USB_PID_DATA0, USB_PID_SETUP); 345 addr = DBGP_EPADDR(devnum, 0); 346 347 ctrl = readl(&ehci_debug->control); 348 ctrl = dbgp_len_update(ctrl, sizeof(req)); 349 ctrl |= DBGP_OUT; 350 ctrl |= DBGP_GO; 351 352 /* Send the setup message */ 353 dbgp_set_data(&req, sizeof(req)); 354 writel(addr, &ehci_debug->address); 355 writel(pids, &ehci_debug->pids); 356 ret = dbgp_wait_until_done(ctrl, DBGP_LOOPS); 357 if (ret < 0) 358 return ret; 359 360 /* Read the result */ 361 return dbgp_bulk_read(devnum, 0, data, size, DBGP_LOOPS); 362} 363 364/* Find a PCI capability */ 365static u32 __init find_cap(u32 num, u32 slot, u32 func, int cap) 366{ 367 u8 pos; 368 int bytes; 369 370 if (!(read_pci_config_16(num, slot, func, PCI_STATUS) & 371 PCI_STATUS_CAP_LIST)) 372 return 0; 373 374 pos = read_pci_config_byte(num, slot, func, PCI_CAPABILITY_LIST); 375 for (bytes = 0; bytes < 48 && pos >= 0x40; bytes++) { 376 u8 id; 377 378 pos &= ~3; 379 id = read_pci_config_byte(num, slot, func, pos+PCI_CAP_LIST_ID); 380 if (id == 0xff) 381 break; 382 if (id == cap) 383 return pos; 384 385 pos = read_pci_config_byte(num, slot, func, 386 pos+PCI_CAP_LIST_NEXT); 387 } 388 return 0; 389} 390 391static u32 __init __find_dbgp(u32 bus, u32 slot, u32 func) 392{ 393 u32 class; 394 395 class = read_pci_config(bus, slot, func, PCI_CLASS_REVISION); 396 if ((class >> 8) != PCI_CLASS_SERIAL_USB_EHCI) 397 return 0; 398 399 return find_cap(bus, slot, func, PCI_CAP_ID_EHCI_DEBUG); 400} 401 402static u32 __init find_dbgp(int ehci_num, u32 *rbus, u32 *rslot, u32 *rfunc) 403{ 404 u32 bus, slot, func; 405 406 for (bus = 0; bus < 256; bus++) { 407 for (slot = 0; slot < 32; slot++) { 408 for (func = 0; func < 8; func++) { 409 unsigned cap; 410 411 cap = __find_dbgp(bus, slot, func); 412 413 if (!cap) 414 continue; 415 if (ehci_num-- != 0) 416 continue; 417 *rbus = bus; 418 *rslot = slot; 419 *rfunc = func; 420 return cap; 421 } 422 } 423 } 424 return 0; 425} 426 427static int dbgp_ehci_startup(void) 428{ 429 u32 ctrl, cmd, status; 430 int loop; 431 432 /* Claim ownership, but do not enable yet */ 433 ctrl = readl(&ehci_debug->control); 434 ctrl |= DBGP_OWNER; 435 ctrl &= ~(DBGP_ENABLED | DBGP_INUSE); 436 writel(ctrl, &ehci_debug->control); 437 udelay(1); 438 439 dbgp_ehci_status("EHCI startup"); 440 /* Start the ehci running */ 441 cmd = readl(&ehci_regs->command); 442 cmd &= ~(CMD_LRESET | CMD_IAAD | CMD_PSE | CMD_ASE | CMD_RESET); 443 cmd |= CMD_RUN; 444 writel(cmd, &ehci_regs->command); 445 446 /* Ensure everything is routed to the EHCI */ 447 writel(FLAG_CF, &ehci_regs->configured_flag); 448 449 /* Wait until the controller is no longer halted */ 450 loop = 10; 451 do { 452 status = readl(&ehci_regs->status); 453 if (!(status & STS_HALT)) 454 break; 455 udelay(1); 456 } while (--loop > 0); 457 458 if (!loop) { 459 dbgp_printk("ehci can not be started\n"); 460 return -ENODEV; 461 } 462 dbgp_printk("ehci started\n"); 463 return 0; 464} 465 466static int dbgp_ehci_controller_reset(void) 467{ 468 int loop = 250 * 1000; 469 u32 cmd; 470 471 /* Reset the EHCI controller */ 472 cmd = readl(&ehci_regs->command); 473 cmd |= CMD_RESET; 474 writel(cmd, &ehci_regs->command); 475 do { 476 cmd = readl(&ehci_regs->command); 477 } while ((cmd & CMD_RESET) && (--loop > 0)); 478 479 if (!loop) { 480 dbgp_printk("can not reset ehci\n"); 481 return -1; 482 } 483 dbgp_ehci_status("ehci reset done"); 484 return 0; 485} 486static int ehci_wait_for_port(int port); 487/* Return 0 on success 488 * Return -ENODEV for any general failure 489 * Return -EIO if wait for port fails 490 */ 491int dbgp_external_startup(void) 492{ 493 int devnum; 494 struct usb_debug_descriptor dbgp_desc; 495 int ret; 496 u32 ctrl, portsc, cmd; 497 int dbg_port = dbgp_phys_port; 498 int tries = 3; 499 int reset_port_tries = 1; 500 int try_hard_once = 1; 501 502try_port_reset_again: 503 ret = dbgp_ehci_startup(); 504 if (ret) 505 return ret; 506 507 /* Wait for a device to show up in the debug port */ 508 ret = ehci_wait_for_port(dbg_port); 509 if (ret < 0) { 510 portsc = readl(&ehci_regs->port_status[dbg_port - 1]); 511 if (!(portsc & PORT_CONNECT) && try_hard_once) { 512 /* Last ditch effort to try to force enable 513 * the debug device by using the packet test 514 * ehci command to try and wake it up. */ 515 try_hard_once = 0; 516 cmd = readl(&ehci_regs->command); 517 cmd &= ~CMD_RUN; 518 writel(cmd, &ehci_regs->command); 519 portsc = readl(&ehci_regs->port_status[dbg_port - 1]); 520 portsc |= PORT_TEST_PKT; 521 writel(portsc, &ehci_regs->port_status[dbg_port - 1]); 522 dbgp_ehci_status("Trying to force debug port online"); 523 mdelay(50); 524 dbgp_ehci_controller_reset(); 525 goto try_port_reset_again; 526 } else if (reset_port_tries--) { 527 goto try_port_reset_again; 528 } 529 dbgp_printk("No device found in debug port\n"); 530 return -EIO; 531 } 532 dbgp_ehci_status("wait for port done"); 533 534 /* Enable the debug port */ 535 ctrl = readl(&ehci_debug->control); 536 ctrl |= DBGP_CLAIM; 537 writel(ctrl, &ehci_debug->control); 538 ctrl = readl(&ehci_debug->control); 539 if ((ctrl & DBGP_CLAIM) != DBGP_CLAIM) { 540 dbgp_printk("No device in debug port\n"); 541 writel(ctrl & ~DBGP_CLAIM, &ehci_debug->control); 542 return -ENODEV; 543 } 544 dbgp_ehci_status("debug ported enabled"); 545 546 /* Completely transfer the debug device to the debug controller */ 547 portsc = readl(&ehci_regs->port_status[dbg_port - 1]); 548 portsc &= ~PORT_PE; 549 writel(portsc, &ehci_regs->port_status[dbg_port - 1]); 550 551 dbgp_mdelay(100); 552 553try_again: 554 /* Find the debug device and make it device number 127 */ 555 for (devnum = 0; devnum <= 127; devnum++) { 556 ret = dbgp_control_msg(devnum, 557 USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE, 558 USB_REQ_GET_DESCRIPTOR, (USB_DT_DEBUG << 8), 0, 559 &dbgp_desc, sizeof(dbgp_desc)); 560 if (ret > 0) 561 break; 562 } 563 if (devnum > 127) { 564 dbgp_printk("Could not find attached debug device\n"); 565 goto err; 566 } 567 if (ret < 0) { 568 dbgp_printk("Attached device is not a debug device\n"); 569 goto err; 570 } 571 dbgp_endpoint_out = dbgp_desc.bDebugOutEndpoint; 572 dbgp_endpoint_in = dbgp_desc.bDebugInEndpoint; 573 574 /* Move the device to 127 if it isn't already there */ 575 if (devnum != USB_DEBUG_DEVNUM) { 576 ret = dbgp_control_msg(devnum, 577 USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE, 578 USB_REQ_SET_ADDRESS, USB_DEBUG_DEVNUM, 0, NULL, 0); 579 if (ret < 0) { 580 dbgp_printk("Could not move attached device to %d\n", 581 USB_DEBUG_DEVNUM); 582 goto err; 583 } 584 devnum = USB_DEBUG_DEVNUM; 585 dbgp_printk("debug device renamed to 127\n"); 586 } 587 588 /* Enable the debug interface */ 589 ret = dbgp_control_msg(USB_DEBUG_DEVNUM, 590 USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE, 591 USB_REQ_SET_FEATURE, USB_DEVICE_DEBUG_MODE, 0, NULL, 0); 592 if (ret < 0) { 593 dbgp_printk(" Could not enable the debug device\n"); 594 goto err; 595 } 596 dbgp_printk("debug interface enabled\n"); 597 /* Perform a small write to get the even/odd data state in sync 598 */ 599 ret = dbgp_bulk_write(USB_DEBUG_DEVNUM, dbgp_endpoint_out, " ", 1); 600 if (ret < 0) { 601 dbgp_printk("dbgp_bulk_write failed: %d\n", ret); 602 goto err; 603 } 604 dbgp_printk("small write doned\n"); 605 dbgp_not_safe = 0; 606 607 return 0; 608err: 609 if (tries--) 610 goto try_again; 611 return -ENODEV; 612} 613EXPORT_SYMBOL_GPL(dbgp_external_startup); 614 615static int ehci_reset_port(int port) 616{ 617 u32 portsc; 618 u32 delay_time, delay; 619 int loop; 620 621 dbgp_ehci_status("reset port"); 622 /* Reset the usb debug port */ 623 portsc = readl(&ehci_regs->port_status[port - 1]); 624 portsc &= ~PORT_PE; 625 portsc |= PORT_RESET; 626 writel(portsc, &ehci_regs->port_status[port - 1]); 627 628 delay = HUB_ROOT_RESET_TIME; 629 for (delay_time = 0; delay_time < HUB_RESET_TIMEOUT; 630 delay_time += delay) { 631 dbgp_mdelay(delay); 632 portsc = readl(&ehci_regs->port_status[port - 1]); 633 if (!(portsc & PORT_RESET)) 634 break; 635 } 636 if (portsc & PORT_RESET) { 637 /* force reset to complete */ 638 loop = 100 * 1000; 639 writel(portsc & ~(PORT_RWC_BITS | PORT_RESET), 640 &ehci_regs->port_status[port - 1]); 641 do { 642 udelay(1); 643 portsc = readl(&ehci_regs->port_status[port-1]); 644 } while ((portsc & PORT_RESET) && (--loop > 0)); 645 } 646 647 /* Device went away? */ 648 if (!(portsc & PORT_CONNECT)) 649 return -ENOTCONN; 650 651 /* bomb out completely if something weird happend */ 652 if ((portsc & PORT_CSC)) 653 return -EINVAL; 654 655 /* If we've finished resetting, then break out of the loop */ 656 if (!(portsc & PORT_RESET) && (portsc & PORT_PE)) 657 return 0; 658 return -EBUSY; 659} 660 661static int ehci_wait_for_port(int port) 662{ 663 u32 status; 664 int ret, reps; 665 666 for (reps = 0; reps < 300; reps++) { 667 status = readl(&ehci_regs->status); 668 if (status & STS_PCD) 669 break; 670 dbgp_mdelay(1); 671 } 672 ret = ehci_reset_port(port); 673 if (ret == 0) 674 return 0; 675 return -ENOTCONN; 676} 677 678typedef void (*set_debug_port_t)(int port); 679 680static void __init default_set_debug_port(int port) 681{ 682} 683 684static set_debug_port_t __initdata set_debug_port = default_set_debug_port; 685 686static void __init nvidia_set_debug_port(int port) 687{ 688 u32 dword; 689 dword = read_pci_config(ehci_dev.bus, ehci_dev.slot, ehci_dev.func, 690 0x74); 691 dword &= ~(0x0f<<12); 692 dword |= ((port & 0x0f)<<12); 693 write_pci_config(ehci_dev.bus, ehci_dev.slot, ehci_dev.func, 0x74, 694 dword); 695 dbgp_printk("set debug port to %d\n", port); 696} 697 698static void __init detect_set_debug_port(void) 699{ 700 u32 vendorid; 701 702 vendorid = read_pci_config(ehci_dev.bus, ehci_dev.slot, ehci_dev.func, 703 0x00); 704 705 if ((vendorid & 0xffff) == 0x10de) { 706 dbgp_printk("using nvidia set_debug_port\n"); 707 set_debug_port = nvidia_set_debug_port; 708 } 709} 710 711/* The code in early_ehci_bios_handoff() is derived from the usb pci 712 * quirk initialization, but altered so as to use the early PCI 713 * routines. */ 714#define EHCI_USBLEGSUP_BIOS (1 << 16) /* BIOS semaphore */ 715#define EHCI_USBLEGCTLSTS 4 /* legacy control/status */ 716static void __init early_ehci_bios_handoff(void) 717{ 718 u32 hcc_params = readl(&ehci_caps->hcc_params); 719 int offset = (hcc_params >> 8) & 0xff; 720 u32 cap; 721 int msec; 722 723 if (!offset) 724 return; 725 726 cap = read_pci_config(ehci_dev.bus, ehci_dev.slot, 727 ehci_dev.func, offset); 728 dbgp_printk("dbgp: ehci BIOS state %08x\n", cap); 729 730 if ((cap & 0xff) == 1 && (cap & EHCI_USBLEGSUP_BIOS)) { 731 dbgp_printk("dbgp: BIOS handoff\n"); 732 write_pci_config_byte(ehci_dev.bus, ehci_dev.slot, 733 ehci_dev.func, offset + 3, 1); 734 } 735 736 /* if boot firmware now owns EHCI, spin till it hands it over. */ 737 msec = 1000; 738 while ((cap & EHCI_USBLEGSUP_BIOS) && (msec > 0)) { 739 mdelay(10); 740 msec -= 10; 741 cap = read_pci_config(ehci_dev.bus, ehci_dev.slot, 742 ehci_dev.func, offset); 743 } 744 745 if (cap & EHCI_USBLEGSUP_BIOS) { 746 /* well, possibly buggy BIOS... try to shut it down, 747 * and hope nothing goes too wrong */ 748 dbgp_printk("dbgp: BIOS handoff failed: %08x\n", cap); 749 write_pci_config_byte(ehci_dev.bus, ehci_dev.slot, 750 ehci_dev.func, offset + 2, 0); 751 } 752 753 /* just in case, always disable EHCI SMIs */ 754 write_pci_config_byte(ehci_dev.bus, ehci_dev.slot, ehci_dev.func, 755 offset + EHCI_USBLEGCTLSTS, 0); 756} 757 758static int __init ehci_setup(void) 759{ 760 u32 ctrl, portsc, hcs_params; 761 u32 debug_port, new_debug_port = 0, n_ports; 762 int ret, i; 763 int port_map_tried; 764 int playtimes = 3; 765 766 early_ehci_bios_handoff(); 767 768try_next_time: 769 port_map_tried = 0; 770 771try_next_port: 772 773 hcs_params = readl(&ehci_caps->hcs_params); 774 debug_port = HCS_DEBUG_PORT(hcs_params); 775 dbgp_phys_port = debug_port; 776 n_ports = HCS_N_PORTS(hcs_params); 777 778 dbgp_printk("debug_port: %d\n", debug_port); 779 dbgp_printk("n_ports: %d\n", n_ports); 780 dbgp_ehci_status(""); 781 782 for (i = 1; i <= n_ports; i++) { 783 portsc = readl(&ehci_regs->port_status[i-1]); 784 dbgp_printk("portstatus%d: %08x\n", i, portsc); 785 } 786 787 if (port_map_tried && (new_debug_port != debug_port)) { 788 if (--playtimes) { 789 set_debug_port(new_debug_port); 790 goto try_next_time; 791 } 792 return -1; 793 } 794 795 /* Only reset the controller if it is not already in the 796 * configured state */ 797 if (!(readl(&ehci_regs->configured_flag) & FLAG_CF)) { 798 if (dbgp_ehci_controller_reset() != 0) 799 return -1; 800 } else { 801 dbgp_ehci_status("ehci skip - already configured"); 802 } 803 804 ret = dbgp_external_startup(); 805 if (ret == -EIO) 806 goto next_debug_port; 807 808 if (ret < 0) { 809 /* Things didn't work so remove my claim */ 810 ctrl = readl(&ehci_debug->control); 811 ctrl &= ~(DBGP_CLAIM | DBGP_OUT); 812 writel(ctrl, &ehci_debug->control); 813 return -1; 814 } 815 return 0; 816 817next_debug_port: 818 port_map_tried |= (1<<(debug_port - 1)); 819 new_debug_port = ((debug_port-1+1)%n_ports) + 1; 820 if (port_map_tried != ((1<<n_ports) - 1)) { 821 set_debug_port(new_debug_port); 822 goto try_next_port; 823 } 824 if (--playtimes) { 825 set_debug_port(new_debug_port); 826 goto try_next_time; 827 } 828 829 return -1; 830} 831 832int __init early_dbgp_init(char *s) 833{ 834 u32 debug_port, bar, offset; 835 u32 bus, slot, func, cap; 836 void __iomem *ehci_bar; 837 u32 dbgp_num; 838 u32 bar_val; 839 char *e; 840 int ret; 841 u8 byte; 842 843 if (!early_pci_allowed()) 844 return -1; 845 846 dbgp_num = 0; 847 if (*s) 848 dbgp_num = simple_strtoul(s, &e, 10); 849 dbgp_printk("dbgp_num: %d\n", dbgp_num); 850 851 cap = find_dbgp(dbgp_num, &bus, &slot, &func); 852 if (!cap) 853 return -1; 854 855 dbgp_printk("Found EHCI debug port on %02x:%02x.%1x\n", bus, slot, 856 func); 857 858 debug_port = read_pci_config(bus, slot, func, cap); 859 bar = (debug_port >> 29) & 0x7; 860 bar = (bar * 4) + 0xc; 861 offset = (debug_port >> 16) & 0xfff; 862 dbgp_printk("bar: %02x offset: %03x\n", bar, offset); 863 if (bar != PCI_BASE_ADDRESS_0) { 864 dbgp_printk("only debug ports on bar 1 handled.\n"); 865 866 return -1; 867 } 868 869 bar_val = read_pci_config(bus, slot, func, PCI_BASE_ADDRESS_0); 870 dbgp_printk("bar_val: %02x offset: %03x\n", bar_val, offset); 871 if (bar_val & ~PCI_BASE_ADDRESS_MEM_MASK) { 872 dbgp_printk("only simple 32bit mmio bars supported\n"); 873 874 return -1; 875 } 876 877 /* double check if the mem space is enabled */ 878 byte = read_pci_config_byte(bus, slot, func, 0x04); 879 if (!(byte & 0x2)) { 880 byte |= 0x02; 881 write_pci_config_byte(bus, slot, func, 0x04, byte); 882 dbgp_printk("mmio for ehci enabled\n"); 883 } 884 885 set_fixmap_nocache(FIX_DBGP_BASE, bar_val & PAGE_MASK); 886 ehci_bar = (void __iomem *)__fix_to_virt(FIX_DBGP_BASE); 887 ehci_bar += bar_val & ~PAGE_MASK; 888 dbgp_printk("ehci_bar: %p\n", ehci_bar); 889 890 ehci_caps = ehci_bar; 891 ehci_regs = ehci_bar + HC_LENGTH(readl(&ehci_caps->hc_capbase)); 892 ehci_debug = ehci_bar + offset; 893 ehci_dev.bus = bus; 894 ehci_dev.slot = slot; 895 ehci_dev.func = func; 896 897 detect_set_debug_port(); 898 899 ret = ehci_setup(); 900 if (ret < 0) { 901 dbgp_printk("ehci_setup failed\n"); 902 ehci_debug = NULL; 903 904 return -1; 905 } 906 dbgp_ehci_status("early_init_complete"); 907 908 return 0; 909} 910 911static void early_dbgp_write(struct console *con, const char *str, u32 n) 912{ 913 int chunk, ret; 914 char buf[DBGP_MAX_PACKET]; 915 int use_cr = 0; 916 u32 cmd, ctrl; 917 int reset_run = 0; 918 919 if (!ehci_debug || dbgp_not_safe) 920 return; 921 922 cmd = readl(&ehci_regs->command); 923 if (unlikely(!(cmd & CMD_RUN))) { 924 /* If the ehci controller is not in the run state do extended 925 * checks to see if the acpi or some other initialization also 926 * reset the ehci debug port */ 927 ctrl = readl(&ehci_debug->control); 928 if (!(ctrl & DBGP_ENABLED)) { 929 dbgp_not_safe = 1; 930 dbgp_external_startup(); 931 } else { 932 cmd |= CMD_RUN; 933 writel(cmd, &ehci_regs->command); 934 reset_run = 1; 935 } 936 } 937 while (n > 0) { 938 for (chunk = 0; chunk < DBGP_MAX_PACKET && n > 0; 939 str++, chunk++, n--) { 940 if (!use_cr && *str == '\n') { 941 use_cr = 1; 942 buf[chunk] = '\r'; 943 str--; 944 n++; 945 continue; 946 } 947 if (use_cr) 948 use_cr = 0; 949 buf[chunk] = *str; 950 } 951 if (chunk > 0) { 952 ret = dbgp_bulk_write(USB_DEBUG_DEVNUM, 953 dbgp_endpoint_out, buf, chunk); 954 } 955 } 956 if (unlikely(reset_run)) { 957 cmd = readl(&ehci_regs->command); 958 cmd &= ~CMD_RUN; 959 writel(cmd, &ehci_regs->command); 960 } 961} 962 963struct console early_dbgp_console = { 964 .name = "earlydbg", 965 .write = early_dbgp_write, 966 .flags = CON_PRINTBUFFER, 967 .index = -1, 968}; 969 970int dbgp_reset_prep(void) 971{ 972 u32 ctrl; 973 974 dbgp_not_safe = 1; 975 if (!ehci_debug) 976 return 0; 977 978 if ((early_dbgp_console.index != -1 && 979 !(early_dbgp_console.flags & CON_BOOT)) || 980 dbgp_kgdb_mode) 981 return 1; 982 /* This means the console is not initialized, or should get 983 * shutdown so as to allow for reuse of the usb device, which 984 * means it is time to shutdown the usb debug port. */ 985 ctrl = readl(&ehci_debug->control); 986 if (ctrl & DBGP_ENABLED) { 987 ctrl &= ~(DBGP_CLAIM); 988 writel(ctrl, &ehci_debug->control); 989 } 990 return 0; 991} 992EXPORT_SYMBOL_GPL(dbgp_reset_prep); 993 994#ifdef CONFIG_KGDB 995 996static char kgdbdbgp_buf[DBGP_MAX_PACKET]; 997static int kgdbdbgp_buf_sz; 998static int kgdbdbgp_buf_idx; 999static int kgdbdbgp_loop_cnt = DBGP_LOOPS; 1000 1001static int kgdbdbgp_read_char(void) 1002{ 1003 int ret; 1004 1005 if (kgdbdbgp_buf_idx < kgdbdbgp_buf_sz) { 1006 char ch = kgdbdbgp_buf[kgdbdbgp_buf_idx++]; 1007 return ch; 1008 } 1009 1010 ret = dbgp_bulk_read(USB_DEBUG_DEVNUM, dbgp_endpoint_in, 1011 &kgdbdbgp_buf, DBGP_MAX_PACKET, 1012 kgdbdbgp_loop_cnt); 1013 if (ret <= 0) 1014 return NO_POLL_CHAR; 1015 kgdbdbgp_buf_sz = ret; 1016 kgdbdbgp_buf_idx = 1; 1017 return kgdbdbgp_buf[0]; 1018} 1019 1020static void kgdbdbgp_write_char(u8 chr) 1021{ 1022 early_dbgp_write(NULL, &chr, 1); 1023} 1024 1025static struct kgdb_io kgdbdbgp_io_ops = { 1026 .name = "kgdbdbgp", 1027 .read_char = kgdbdbgp_read_char, 1028 .write_char = kgdbdbgp_write_char, 1029}; 1030 1031static int kgdbdbgp_wait_time; 1032 1033static int __init kgdbdbgp_parse_config(char *str) 1034{ 1035 char *ptr; 1036 1037 if (!ehci_debug) { 1038 if (early_dbgp_init(str)) 1039 return -1; 1040 } 1041 ptr = strchr(str, ','); 1042 if (ptr) { 1043 ptr++; 1044 kgdbdbgp_wait_time = simple_strtoul(ptr, &ptr, 10); 1045 } 1046 kgdb_register_io_module(&kgdbdbgp_io_ops); 1047 kgdbdbgp_io_ops.is_console = early_dbgp_console.index != -1; 1048 1049 return 0; 1050} 1051early_param("kgdbdbgp", kgdbdbgp_parse_config); 1052 1053static int kgdbdbgp_reader_thread(void *ptr) 1054{ 1055 int ret; 1056 1057 while (readl(&ehci_debug->control) & DBGP_ENABLED) { 1058 kgdbdbgp_loop_cnt = 1; 1059 ret = kgdbdbgp_read_char(); 1060 kgdbdbgp_loop_cnt = DBGP_LOOPS; 1061 if (ret != NO_POLL_CHAR) { 1062 if (ret == 0x3 || ret == '$') { 1063 if (ret == '$') 1064 kgdbdbgp_buf_idx--; 1065 kgdb_breakpoint(); 1066 } 1067 continue; 1068 } 1069 schedule_timeout_interruptible(kgdbdbgp_wait_time * HZ); 1070 } 1071 return 0; 1072} 1073 1074static int __init kgdbdbgp_start_thread(void) 1075{ 1076 if (dbgp_kgdb_mode && kgdbdbgp_wait_time) 1077 kthread_run(kgdbdbgp_reader_thread, NULL, "%s", "dbgp"); 1078 1079 return 0; 1080} 1081module_init(kgdbdbgp_start_thread); 1082#endif /* CONFIG_KGDB */ 1083