remote_gdb.cc revision 12122:20512f6810d7
1/* 2 * Copyright 2015 LabWare 3 * Copyright 2014 Google, Inc. 4 * Copyright (c) 2002-2005 The Regents of The University of Michigan 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions are 9 * met: redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer; 11 * redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution; 14 * neither the name of the copyright holders nor the names of its 15 * contributors may be used to endorse or promote products derived from 16 * this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 * 30 * Authors: Nathan Binkert 31 * Boris Shingarov 32 */ 33 34/* 35 * Copyright (c) 1990, 1993 The Regents of the University of California 36 * All rights reserved 37 * 38 * This software was developed by the Computer Systems Engineering group 39 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and 40 * contributed to Berkeley. 41 * 42 * All advertising materials mentioning features or use of this software 43 * must display the following acknowledgement: 44 * This product includes software developed by the University of 45 * California, Lawrence Berkeley Laboratories. 46 * 47 * Redistribution and use in source and binary forms, with or without 48 * modification, are permitted provided that the following conditions 49 * are met: 50 * 1. Redistributions of source code must retain the above copyright 51 * notice, this list of conditions and the following disclaimer. 52 * 2. Redistributions in binary form must reproduce the above copyright 53 * notice, this list of conditions and the following disclaimer in the 54 * documentation and/or other materials provided with the distribution. 55 * 3. All advertising materials mentioning features or use of this software 56 * must display the following acknowledgement: 57 * This product includes software developed by the University of 58 * California, Berkeley and its contributors. 59 * 4. Neither the name of the University nor the names of its contributors 60 * may be used to endorse or promote products derived from this software 61 * without specific prior written permission. 62 * 63 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 64 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 65 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 66 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 67 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 68 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 69 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 70 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 71 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 72 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 73 * SUCH DAMAGE. 74 * 75 * @(#)kgdb_stub.c 8.4 (Berkeley) 1/12/94 76 */ 77 78/*- 79 * Copyright (c) 2001 The NetBSD Foundation, Inc. 80 * All rights reserved. 81 * 82 * This code is derived from software contributed to The NetBSD Foundation 83 * by Jason R. Thorpe. 84 * 85 * Redistribution and use in source and binary forms, with or without 86 * modification, are permitted provided that the following conditions 87 * are met: 88 * 1. Redistributions of source code must retain the above copyright 89 * notice, this list of conditions and the following disclaimer. 90 * 2. Redistributions in binary form must reproduce the above copyright 91 * notice, this list of conditions and the following disclaimer in the 92 * documentation and/or other materials provided with the distribution. 93 * 3. All advertising materials mentioning features or use of this software 94 * must display the following acknowledgement: 95 * This product includes software developed by the NetBSD 96 * Foundation, Inc. and its contributors. 97 * 4. Neither the name of The NetBSD Foundation nor the names of its 98 * contributors may be used to endorse or promote products derived 99 * from this software without specific prior written permission. 100 * 101 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 102 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 103 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 104 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 105 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 106 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 107 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 108 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 109 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 110 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 111 * POSSIBILITY OF SUCH DAMAGE. 112 */ 113 114/* 115 * $NetBSD: kgdb_stub.c,v 1.8 2001/07/07 22:58:00 wdk Exp $ 116 * 117 * Taken from NetBSD 118 * 119 * "Stub" to allow remote cpu to debug over a serial line using gdb. 120 */ 121 122#include "base/remote_gdb.hh" 123 124#include <sys/signal.h> 125#include <unistd.h> 126 127#include <csignal> 128#include <cstdint> 129#include <cstdio> 130#include <string> 131 132#include "arch/vtophys.hh" 133#include "base/intmath.hh" 134#include "base/socket.hh" 135#include "base/trace.hh" 136#include "config/the_isa.hh" 137#include "cpu/base.hh" 138#include "cpu/static_inst.hh" 139#include "cpu/thread_context.hh" 140#include "debug/GDBAll.hh" 141#include "mem/fs_translating_port_proxy.hh" 142#include "mem/port.hh" 143#include "mem/se_translating_port_proxy.hh" 144#include "sim/full_system.hh" 145#include "sim/system.hh" 146 147using namespace std; 148using namespace TheISA; 149 150static const char GDBStart = '$'; 151static const char GDBEnd = '#'; 152static const char GDBGoodP = '+'; 153static const char GDBBadP = '-'; 154 155static const int GDBPacketBufLen = 1024; 156 157#ifndef NDEBUG 158vector<BaseRemoteGDB *> debuggers; 159 160void 161debugger() 162{ 163 static int current_debugger = -1; 164 if (current_debugger >= 0 && current_debugger < (int)debuggers.size()) { 165 BaseRemoteGDB *gdb = debuggers[current_debugger]; 166 if (!gdb->isattached()) 167 gdb->listener->accept(); 168 if (gdb->isattached()) 169 gdb->trap(SIGILL); 170 } 171} 172#endif 173 174/////////////////////////////////////////////////////////// 175// 176// 177// 178 179GDBListener::InputEvent::InputEvent(GDBListener *l, int fd, int e) 180 : PollEvent(fd, e), listener(l) 181{} 182 183void 184GDBListener::InputEvent::process(int revent) 185{ 186 listener->accept(); 187} 188 189GDBListener::GDBListener(BaseRemoteGDB *g, int p) 190 : inputEvent(NULL), gdb(g), port(p) 191{ 192 assert(!gdb->listener); 193 gdb->listener = this; 194} 195 196GDBListener::~GDBListener() 197{ 198 delete inputEvent; 199} 200 201string 202GDBListener::name() 203{ 204 return gdb->name() + ".listener"; 205} 206 207void 208GDBListener::listen() 209{ 210 if (ListenSocket::allDisabled()) { 211 warn_once("Sockets disabled, not accepting gdb connections"); 212 return; 213 } 214 215 while (!listener.listen(port, true)) { 216 DPRINTF(GDBMisc, "Can't bind port %d\n", port); 217 port++; 218 } 219 220 inputEvent = new InputEvent(this, listener.getfd(), POLLIN); 221 pollQueue.schedule(inputEvent); 222 223#ifndef NDEBUG 224 gdb->number = debuggers.size(); 225 debuggers.push_back(gdb); 226#endif 227 228#ifndef NDEBUG 229 ccprintf(cerr, "%d: %s: listening for remote gdb #%d on port %d\n", 230 curTick(), name(), gdb->number, port); 231#else 232 ccprintf(cerr, "%d: %s: listening for remote gdb on port %d\n", 233 curTick(), name(), port); 234#endif 235} 236 237void 238GDBListener::accept() 239{ 240 if (!listener.islistening()) 241 panic("GDBListener::accept(): cannot accept if we're not listening!"); 242 243 int sfd = listener.accept(true); 244 245 if (sfd != -1) { 246 if (gdb->isattached()) 247 close(sfd); 248 else 249 gdb->attach(sfd); 250 } 251} 252 253int 254GDBListener::getPort() const 255{ 256 panic_if(!listener.islistening(), 257 "Remote GDB port is unknown until GDBListener::listen() has " 258 "been called.\n"); 259 260 return port; 261} 262 263BaseRemoteGDB::InputEvent::InputEvent(BaseRemoteGDB *g, int fd, int e) 264 : PollEvent(fd, e), gdb(g) 265{} 266 267void 268BaseRemoteGDB::InputEvent::process(int revent) 269{ 270 if (gdb->trapEvent.scheduled()) { 271 warn("GDB trap event has already been scheduled! " 272 "Ignoring this input event."); 273 return; 274 } 275 276 if (revent & POLLIN) { 277 gdb->trapEvent.type(SIGILL); 278 gdb->scheduleInstCommitEvent(&gdb->trapEvent, 0); 279 } else if (revent & POLLNVAL) { 280 gdb->descheduleInstCommitEvent(&gdb->trapEvent); 281 gdb->detach(); 282 } 283} 284 285void 286BaseRemoteGDB::TrapEvent::process() 287{ 288 gdb->trap(_type); 289} 290 291void 292BaseRemoteGDB::SingleStepEvent::process() 293{ 294 if (!gdb->singleStepEvent.scheduled()) 295 gdb->scheduleInstCommitEvent(&gdb->singleStepEvent, 1); 296 gdb->trap(SIGTRAP); 297} 298 299BaseRemoteGDB::BaseRemoteGDB(System *_system, ThreadContext *c) : 300 inputEvent(NULL), trapEvent(this), listener(NULL), 301 number(-1), fd(-1), active(false), attached(false), system(_system), 302 context(c), singleStepEvent(this) 303{ 304} 305 306BaseRemoteGDB::~BaseRemoteGDB() 307{ 308 if (inputEvent) 309 delete inputEvent; 310} 311 312string 313BaseRemoteGDB::name() 314{ 315 return system->name() + ".remote_gdb"; 316} 317 318bool 319BaseRemoteGDB::isattached() 320{ return attached; } 321 322void 323BaseRemoteGDB::attach(int f) 324{ 325 fd = f; 326 327 inputEvent = new InputEvent(this, fd, POLLIN); 328 pollQueue.schedule(inputEvent); 329 330 attached = true; 331 DPRINTFN("remote gdb attached\n"); 332} 333 334void 335BaseRemoteGDB::detach() 336{ 337 attached = false; 338 active = false; 339 clearSingleStep(); 340 close(fd); 341 fd = -1; 342 343 pollQueue.remove(inputEvent); 344 DPRINTFN("remote gdb detached\n"); 345} 346 347///////////////////////// 348// 349// 350 351uint8_t 352BaseRemoteGDB::getbyte() 353{ 354 uint8_t b; 355 if (::read(fd, &b, sizeof(b)) == sizeof(b)) 356 return b; 357 358 throw BadClient("Couldn't read data from debugger."); 359} 360 361void 362BaseRemoteGDB::putbyte(uint8_t b) 363{ 364 if (::write(fd, &b, sizeof(b)) == sizeof(b)) 365 return; 366 367 throw BadClient("Couldn't write data to the debugger."); 368} 369 370// Send a packet to gdb 371void 372BaseRemoteGDB::send(const char *bp) 373{ 374 const char *p; 375 uint8_t csum, c; 376 377 DPRINTF(GDBSend, "send: %s\n", bp); 378 379 do { 380 p = bp; 381 // Start sending a packet 382 putbyte(GDBStart); 383 // Send the contents, and also keep a check sum. 384 for (csum = 0; (c = *p); p++) { 385 putbyte(c); 386 csum += c; 387 } 388 // Send the ending character. 389 putbyte(GDBEnd); 390 // Send the checksum. 391 putbyte(i2digit(csum >> 4)); 392 putbyte(i2digit(csum)); 393 // Try transmitting over and over again until the other end doesn't 394 // send an error back. 395 c = getbyte(); 396 } while ((c & 0x7f) == GDBBadP); 397} 398 399// Receive a packet from gdb 400int 401BaseRemoteGDB::recv(char *bp, int maxlen) 402{ 403 char *p; 404 uint8_t c; 405 int csum; 406 int len; 407 408 do { 409 p = bp; 410 csum = len = 0; 411 // Find the beginning of a packet 412 while ((c = getbyte()) != GDBStart); 413 414 // Read until you find the end of the data in the packet, and keep 415 // track of the check sum. 416 while (len < maxlen) { 417 c = getbyte(); 418 if (c == GDBEnd) 419 break; 420 c &= 0x7f; 421 csum += c; 422 *p++ = c; 423 len++; 424 } 425 426 // Mask the check sum, and terminate the command string. 427 csum &= 0xff; 428 *p = '\0'; 429 430 // If the command was too long, report an error. 431 if (len >= maxlen) { 432 putbyte(GDBBadP); 433 continue; 434 } 435 436 // Bring in the checksum. If the check sum matches, csum will be 0. 437 csum -= digit2i(getbyte()) * 16; 438 csum -= digit2i(getbyte()); 439 440 // If the check sum was correct 441 if (csum == 0) { 442 // Report that the packet was received correctly 443 putbyte(GDBGoodP); 444 // Sequence present? 445 if (bp[2] == ':') { 446 putbyte(bp[0]); 447 putbyte(bp[1]); 448 len -= 3; 449 memcpy(bp, bp+3, len); 450 } 451 break; 452 } 453 // Otherwise, report that there was a mistake. 454 putbyte(GDBBadP); 455 } while (1); 456 457 DPRINTF(GDBRecv, "recv: %s\n", bp); 458 459 return len; 460} 461 462// Read bytes from kernel address space for debugger. 463bool 464BaseRemoteGDB::read(Addr vaddr, size_t size, char *data) 465{ 466 static Addr lastaddr = 0; 467 static size_t lastsize = 0; 468 469 if (vaddr < 10) { 470 DPRINTF(GDBRead, "read: reading memory location zero!\n"); 471 vaddr = lastaddr + lastsize; 472 } 473 474 DPRINTF(GDBRead, "read: addr=%#x, size=%d", vaddr, size); 475 476 if (FullSystem) { 477 FSTranslatingPortProxy &proxy = context->getVirtProxy(); 478 proxy.readBlob(vaddr, (uint8_t*)data, size); 479 } else { 480 SETranslatingPortProxy &proxy = context->getMemProxy(); 481 proxy.readBlob(vaddr, (uint8_t*)data, size); 482 } 483 484#if TRACING_ON 485 if (DTRACE(GDBRead)) { 486 if (DTRACE(GDBExtra)) { 487 char buf[1024]; 488 mem2hex(buf, data, size); 489 DPRINTFNR(": %s\n", buf); 490 } else 491 DPRINTFNR("\n"); 492 } 493#endif 494 495 return true; 496} 497 498// Write bytes to kernel address space for debugger. 499bool 500BaseRemoteGDB::write(Addr vaddr, size_t size, const char *data) 501{ 502 static Addr lastaddr = 0; 503 static size_t lastsize = 0; 504 505 if (vaddr < 10) { 506 DPRINTF(GDBWrite, "write: writing memory location zero!\n"); 507 vaddr = lastaddr + lastsize; 508 } 509 510 if (DTRACE(GDBWrite)) { 511 DPRINTFN("write: addr=%#x, size=%d", vaddr, size); 512 if (DTRACE(GDBExtra)) { 513 char buf[1024]; 514 mem2hex(buf, data, size); 515 DPRINTFNR(": %s\n", buf); 516 } else 517 DPRINTFNR("\n"); 518 } 519 if (FullSystem) { 520 FSTranslatingPortProxy &proxy = context->getVirtProxy(); 521 proxy.writeBlob(vaddr, (uint8_t*)data, size); 522 } else { 523 SETranslatingPortProxy &proxy = context->getMemProxy(); 524 proxy.writeBlob(vaddr, (uint8_t*)data, size); 525 } 526 527 return true; 528} 529 530void 531BaseRemoteGDB::clearSingleStep() 532{ 533 descheduleInstCommitEvent(&singleStepEvent); 534} 535 536void 537BaseRemoteGDB::setSingleStep() 538{ 539 if (!singleStepEvent.scheduled()) 540 scheduleInstCommitEvent(&singleStepEvent, 1); 541} 542 543PCEventQueue *BaseRemoteGDB::getPcEventQueue() 544{ 545 return &system->pcEventQueue; 546} 547 548EventQueue * 549BaseRemoteGDB::getComInstEventQueue() 550{ 551 BaseCPU *cpu = context->getCpuPtr(); 552 return cpu->comInstEventQueue[context->threadId()]; 553} 554 555void 556BaseRemoteGDB::scheduleInstCommitEvent(Event *ev, int delta) 557{ 558 EventQueue *eq = getComInstEventQueue(); 559 // Here "ticks" aren't simulator ticks which measure time, they're 560 // instructions committed by the CPU. 561 eq->schedule(ev, eq->getCurTick() + delta); 562} 563 564void 565BaseRemoteGDB::descheduleInstCommitEvent(Event *ev) 566{ 567 if (ev->scheduled()) 568 getComInstEventQueue()->deschedule(ev); 569} 570 571bool 572BaseRemoteGDB::checkBpLen(size_t len) 573{ 574 return len == sizeof(MachInst); 575} 576 577BaseRemoteGDB::HardBreakpoint::HardBreakpoint(BaseRemoteGDB *_gdb, Addr pc) 578 : PCEvent(_gdb->getPcEventQueue(), "HardBreakpoint Event", pc), 579 gdb(_gdb), refcount(0) 580{ 581 DPRINTF(GDBMisc, "creating hardware breakpoint at %#x\n", evpc); 582} 583 584void 585BaseRemoteGDB::HardBreakpoint::process(ThreadContext *tc) 586{ 587 DPRINTF(GDBMisc, "handling hardware breakpoint at %#x\n", pc()); 588 589 if (tc == gdb->context) 590 gdb->trap(SIGTRAP); 591} 592 593void 594BaseRemoteGDB::insertSoftBreak(Addr addr, size_t len) 595{ 596 if (!checkBpLen(len)) 597 throw BadClient("Invalid breakpoint length\n"); 598 599 return insertHardBreak(addr, len); 600} 601 602void 603BaseRemoteGDB::removeSoftBreak(Addr addr, size_t len) 604{ 605 if (!checkBpLen(len)) 606 throw BadClient("Invalid breakpoint length.\n"); 607 608 return removeHardBreak(addr, len); 609} 610 611void 612BaseRemoteGDB::insertHardBreak(Addr addr, size_t len) 613{ 614 if (!checkBpLen(len)) 615 throw BadClient("Invalid breakpoint length\n"); 616 617 DPRINTF(GDBMisc, "Inserting hardware breakpoint at %#x\n", addr); 618 619 HardBreakpoint *&bkpt = hardBreakMap[addr]; 620 if (bkpt == 0) 621 bkpt = new HardBreakpoint(this, addr); 622 623 bkpt->refcount++; 624} 625 626void 627BaseRemoteGDB::removeHardBreak(Addr addr, size_t len) 628{ 629 if (!checkBpLen(len)) 630 throw BadClient("Invalid breakpoint length\n"); 631 632 DPRINTF(GDBMisc, "Removing hardware breakpoint at %#x\n", addr); 633 634 break_iter_t i = hardBreakMap.find(addr); 635 if (i == hardBreakMap.end()) 636 throw CmdError("E0C"); 637 638 HardBreakpoint *hbp = (*i).second; 639 if (--hbp->refcount == 0) { 640 delete hbp; 641 hardBreakMap.erase(i); 642 } 643} 644 645void 646BaseRemoteGDB::setTempBreakpoint(Addr bkpt) 647{ 648 DPRINTF(GDBMisc, "setTempBreakpoint: addr=%#x\n", bkpt); 649 insertHardBreak(bkpt, sizeof(TheISA::MachInst)); 650} 651 652void 653BaseRemoteGDB::clearTempBreakpoint(Addr &bkpt) 654{ 655 DPRINTF(GDBMisc, "setTempBreakpoint: addr=%#x\n", bkpt); 656 removeHardBreak(bkpt, sizeof(TheISA::MachInst)); 657 bkpt = 0; 658} 659 660enum GdbBreakpointType { 661 GdbSoftBp = '0', 662 GdbHardBp = '1', 663 GdbWriteWp = '2', 664 GdbReadWp = '3', 665 GdbAccWp = '4', 666}; 667 668const char * 669BaseRemoteGDB::break_type(char c) 670{ 671 switch(c) { 672 case GdbSoftBp: return "software breakpoint"; 673 case GdbHardBp: return "hardware breakpoint"; 674 case GdbWriteWp: return "write watchpoint"; 675 case GdbReadWp: return "read watchpoint"; 676 case GdbAccWp: return "access watchpoint"; 677 default: return "unknown breakpoint/watchpoint"; 678 } 679} 680 681std::map<char, GdbCommand> BaseRemoteGDB::command_map = { 682 // last signal 683 { '?', { "KGDB_SIGNAL", &BaseRemoteGDB::cmd_signal } }, 684 // set baud (deprecated) 685 { 'b', { "KGDB_SET_BAUD", &BaseRemoteGDB::cmd_unsupported } }, 686 // set breakpoint (deprecated) 687 { 'B', { "KGDB_SET_BREAK", &BaseRemoteGDB::cmd_unsupported } }, 688 // resume 689 { 'c', { "KGDB_CONT", &BaseRemoteGDB::cmd_cont } }, 690 // continue with signal 691 { 'C', { "KGDB_ASYNC_CONT", &BaseRemoteGDB::cmd_async_cont } }, 692 // toggle debug flags (deprecated) 693 { 'd', { "KGDB_DEBUG", &BaseRemoteGDB::cmd_unsupported } }, 694 // detach remote gdb 695 { 'D', { "KGDB_DETACH", &BaseRemoteGDB::cmd_detach } }, 696 // read general registers 697 { 'g', { "KGDB_REG_R", &BaseRemoteGDB::cmd_reg_r } }, 698 // write general registers 699 { 'G', { "KGDB_REG_W", &BaseRemoteGDB::cmd_reg_w } }, 700 // set thread 701 { 'H', { "KGDB_SET_THREAD", &BaseRemoteGDB::cmd_set_thread } }, 702 // step a single cycle 703 { 'i', { "KGDB_CYCLE_STEP", &BaseRemoteGDB::cmd_unsupported } }, 704 // signal then cycle step 705 { 'I', { "KGDB_SIG_CYCLE_STEP", &BaseRemoteGDB::cmd_unsupported } }, 706 // kill program 707 { 'k', { "KGDB_KILL", &BaseRemoteGDB::cmd_detach } }, 708 // read memory 709 { 'm', { "KGDB_MEM_R", &BaseRemoteGDB::cmd_mem_r } }, 710 // write memory 711 { 'M', { "KGDB_MEM_W", &BaseRemoteGDB::cmd_mem_w } }, 712 // read register 713 { 'p', { "KGDB_READ_REG", &BaseRemoteGDB::cmd_unsupported } }, 714 // write register 715 { 'P', { "KGDB_SET_REG", &BaseRemoteGDB::cmd_unsupported } }, 716 // query variable 717 { 'q', { "KGDB_QUERY_VAR", &BaseRemoteGDB::cmd_query_var } }, 718 // set variable 719 { 'Q', { "KGDB_SET_VAR", &BaseRemoteGDB::cmd_unsupported } }, 720 // reset system (deprecated) 721 { 'r', { "KGDB_RESET", &BaseRemoteGDB::cmd_unsupported } }, 722 // step 723 { 's', { "KGDB_STEP", &BaseRemoteGDB::cmd_step } }, 724 // signal and step 725 { 'S', { "KGDB_ASYNC_STEP", &BaseRemoteGDB::cmd_async_step } }, 726 // find out if the thread is alive 727 { 'T', { "KGDB_THREAD_ALIVE", &BaseRemoteGDB::cmd_unsupported } }, 728 // target exited 729 { 'W', { "KGDB_TARGET_EXIT", &BaseRemoteGDB::cmd_unsupported } }, 730 // write memory 731 { 'X', { "KGDB_BINARY_DLOAD", &BaseRemoteGDB::cmd_unsupported } }, 732 // remove breakpoint or watchpoint 733 { 'z', { "KGDB_CLR_HW_BKPT", &BaseRemoteGDB::cmd_clr_hw_bkpt } }, 734 // insert breakpoint or watchpoint 735 { 'Z', { "KGDB_SET_HW_BKPT", &BaseRemoteGDB::cmd_set_hw_bkpt } }, 736}; 737 738 739bool 740BaseRemoteGDB::cmd_unsupported(GdbCommand::Context &ctx) 741{ 742 DPRINTF(GDBMisc, "Unsupported command: %s\n", ctx.cmd->name); 743 DDUMP(GDBMisc, ctx.data, ctx.len); 744 throw Unsupported(); 745} 746 747 748bool 749BaseRemoteGDB::cmd_signal(GdbCommand::Context &ctx) 750{ 751 send(csprintf("S%02x", ctx.type).c_str()); 752 return true; 753} 754 755bool 756BaseRemoteGDB::cmd_cont(GdbCommand::Context &ctx) 757{ 758 const char *p = ctx.data; 759 if (ctx.len) { 760 Addr newPc = hex2i(&p); 761 context->pcState(newPc); 762 } 763 clearSingleStep(); 764 return false; 765} 766 767bool 768BaseRemoteGDB::cmd_async_cont(GdbCommand::Context &ctx) 769{ 770 const char *p = ctx.data; 771 hex2i(&p); 772 if (*p++ == ';') { 773 Addr newPc = hex2i(&p); 774 context->pcState(newPc); 775 } 776 clearSingleStep(); 777 return false; 778} 779 780bool 781BaseRemoteGDB::cmd_detach(GdbCommand::Context &ctx) 782{ 783 detach(); 784 return false; 785} 786 787bool 788BaseRemoteGDB::cmd_reg_r(GdbCommand::Context &ctx) 789{ 790 char buf[2 * regCachePtr->size() + 1]; 791 buf[2 * regCachePtr->size()] = '\0'; 792 mem2hex(buf, regCachePtr->data(), regCachePtr->size()); 793 send(buf); 794 return true; 795} 796 797bool 798BaseRemoteGDB::cmd_reg_w(GdbCommand::Context &ctx) 799{ 800 const char *p = ctx.data; 801 p = hex2mem(regCachePtr->data(), p, regCachePtr->size()); 802 if (p == NULL || *p != '\0') 803 throw CmdError("E01"); 804 805 regCachePtr->setRegs(context); 806 send("OK"); 807 808 return true; 809} 810 811bool 812BaseRemoteGDB::cmd_set_thread(GdbCommand::Context &ctx) 813{ 814 const char *p = ctx.data + 1; // Ignore the subcommand byte. 815 if (hex2i(&p) != 0) 816 throw CmdError("E01"); 817 send("OK"); 818 return true; 819} 820 821bool 822BaseRemoteGDB::cmd_mem_r(GdbCommand::Context &ctx) 823{ 824 const char *p = ctx.data; 825 Addr addr = hex2i(&p); 826 if (*p++ != ',') 827 throw CmdError("E02"); 828 size_t len = hex2i(&p); 829 if (*p != '\0') 830 throw CmdError("E03"); 831 if (!acc(addr, len)) 832 throw CmdError("E05"); 833 834 char buf[len]; 835 if (!read(addr, len, buf)) 836 throw CmdError("E05"); 837 838 char temp[2 * len + 1]; 839 temp[2 * len] = '\0'; 840 mem2hex(temp, buf, len); 841 send(temp); 842 return true; 843} 844 845bool 846BaseRemoteGDB::cmd_mem_w(GdbCommand::Context &ctx) 847{ 848 const char *p = ctx.data; 849 Addr addr = hex2i(&p); 850 if (*p++ != ',') 851 throw CmdError("E06"); 852 size_t len = hex2i(&p); 853 if (*p++ != ':') 854 throw CmdError("E07"); 855 if (len * 2 > ctx.len - (p - ctx.data)) 856 throw CmdError("E08"); 857 char buf[len]; 858 p = (char *)hex2mem(buf, p, len); 859 if (p == NULL) 860 throw CmdError("E09"); 861 if (!acc(addr, len)) 862 throw CmdError("E0A"); 863 if (!write(addr, len, buf)) 864 throw CmdError("E0B"); 865 send("OK"); 866 return true; 867} 868 869bool 870BaseRemoteGDB::cmd_query_var(GdbCommand::Context &ctx) 871{ 872 if (string(ctx.data, ctx.len - 1) != "C") 873 throw Unsupported(); 874 send("QC0"); 875 return true; 876} 877 878bool 879BaseRemoteGDB::cmd_async_step(GdbCommand::Context &ctx) 880{ 881 const char *p = ctx.data; 882 hex2i(&p); // Ignore the subcommand byte. 883 if (*p++ == ';') { 884 Addr newPc = hex2i(&p); 885 context->pcState(newPc); 886 } 887 setSingleStep(); 888 return false; 889} 890 891bool 892BaseRemoteGDB::cmd_step(GdbCommand::Context &ctx) 893{ 894 if (ctx.len) { 895 const char *p = ctx.data; 896 Addr newPc = hex2i(&p); 897 context->pcState(newPc); 898 } 899 setSingleStep(); 900 return false; 901} 902 903bool 904BaseRemoteGDB::cmd_clr_hw_bkpt(GdbCommand::Context &ctx) 905{ 906 const char *p = ctx.data; 907 char subcmd = *p++; 908 if (*p++ != ',') 909 throw CmdError("E0D"); 910 Addr addr = hex2i(&p); 911 if (*p++ != ',') 912 throw CmdError("E0D"); 913 size_t len = hex2i(&p); 914 915 DPRINTF(GDBMisc, "clear %s, addr=%#x, len=%d\n", 916 break_type(subcmd), addr, len); 917 918 switch (subcmd) { 919 case GdbSoftBp: 920 removeSoftBreak(addr, len); 921 break; 922 case GdbHardBp: 923 removeHardBreak(addr, len); 924 break; 925 case GdbWriteWp: 926 case GdbReadWp: 927 case GdbAccWp: 928 default: // unknown 929 throw Unsupported(); 930 } 931 send("OK"); 932 933 return true; 934} 935 936bool 937BaseRemoteGDB::cmd_set_hw_bkpt(GdbCommand::Context &ctx) 938{ 939 const char *p = ctx.data; 940 char subcmd = *p++; 941 if (*p++ != ',') 942 throw CmdError("E0D"); 943 Addr addr = hex2i(&p); 944 if (*p++ != ',') 945 throw CmdError("E0D"); 946 size_t len = hex2i(&p); 947 948 DPRINTF(GDBMisc, "set %s, addr=%#x, len=%d\n", 949 break_type(subcmd), addr, len); 950 951 switch (subcmd) { 952 case GdbSoftBp: 953 insertSoftBreak(addr, len); 954 break; 955 case GdbHardBp: 956 insertHardBreak(addr, len); 957 break; 958 case GdbWriteWp: 959 case GdbReadWp: 960 case GdbAccWp: 961 default: // unknown 962 throw Unsupported(); 963 } 964 send("OK"); 965 966 return true; 967} 968 969 970// This function does all command processing for interfacing to a 971// remote gdb. Note that the error codes are ignored by gdb at 972// present, but might eventually become meaningful. (XXX) It might 973// makes sense to use POSIX errno values, because that is what the 974// gdb/remote.c functions want to return. 975bool 976BaseRemoteGDB::trap(int type) 977{ 978 979 if (!attached) 980 return false; 981 982 DPRINTF(GDBMisc, "trap: PC=%s\n", context->pcState()); 983 984 clearSingleStep(); 985 986 /* 987 * The first entry to this function is normally through 988 * a breakpoint trap in kgdb_connect(), in which case we 989 * must advance past the breakpoint because gdb will not. 990 * 991 * On the first entry here, we expect that gdb is not yet 992 * listening to us, so just enter the interaction loop. 993 * After the debugger is "active" (connected) it will be 994 * waiting for a "signaled" message from us. 995 */ 996 if (!active) { 997 active = true; 998 } else { 999 // Tell remote host that an exception has occurred. 1000 send(csprintf("S%02x", type).c_str()); 1001 } 1002 1003 // Stick frame regs into our reg cache. 1004 regCachePtr = gdbRegs(); 1005 regCachePtr->getRegs(context); 1006 1007 char data[GDBPacketBufLen + 1]; 1008 GdbCommand::Context cmdCtx; 1009 cmdCtx.type = type; 1010 cmdCtx.data = &data[1]; 1011 1012 for (;;) { 1013 try { 1014 size_t datalen = recv(data, sizeof(data)); 1015 if (datalen < 1) 1016 throw BadClient(); 1017 1018 data[datalen] = 0; // Sentinel 1019 cmdCtx.cmd_byte = data[0]; 1020 cmdCtx.len = datalen - 1; 1021 1022 auto cmdIt = command_map.find(cmdCtx.cmd_byte); 1023 if (cmdIt == command_map.end()) { 1024 DPRINTF(GDBMisc, "Unknown command: %c(%#x)\n", 1025 cmdCtx.cmd_byte, cmdCtx.cmd_byte); 1026 throw Unsupported(); 1027 } 1028 cmdCtx.cmd = &(cmdIt->second); 1029 1030 if (!(this->*(cmdCtx.cmd->func))(cmdCtx)) 1031 break; 1032 1033 } catch (BadClient &e) { 1034 if (e.warning) 1035 warn(e.warning); 1036 detach(); 1037 break; 1038 } catch (Unsupported &e) { 1039 send(""); 1040 } catch (CmdError &e) { 1041 send(e.error.c_str()); 1042 } catch (...) { 1043 panic("Unrecognzied GDB exception."); 1044 } 1045 } 1046 1047 return true; 1048} 1049 1050// Convert a hex digit into an integer. 1051// This returns -1 if the argument passed is no valid hex digit. 1052int 1053BaseRemoteGDB::digit2i(char c) 1054{ 1055 if (c >= '0' && c <= '9') 1056 return (c - '0'); 1057 else if (c >= 'a' && c <= 'f') 1058 return (c - 'a' + 10); 1059 else if (c >= 'A' && c <= 'F') 1060 return (c - 'A' + 10); 1061 else 1062 return (-1); 1063} 1064 1065// Convert the low 4 bits of an integer into an hex digit. 1066char 1067BaseRemoteGDB::i2digit(int n) 1068{ 1069 return ("0123456789abcdef"[n & 0x0f]); 1070} 1071 1072// Convert a byte array into an hex string. 1073void 1074BaseRemoteGDB::mem2hex(char *vdst, const char *vsrc, int len) 1075{ 1076 char *dst = vdst; 1077 const char *src = vsrc; 1078 1079 while (len--) { 1080 *dst++ = i2digit(*src >> 4); 1081 *dst++ = i2digit(*src++); 1082 } 1083 *dst = '\0'; 1084} 1085 1086// Convert an hex string into a byte array. 1087// This returns a pointer to the character following the last valid 1088// hex digit. If the string ends in the middle of a byte, NULL is 1089// returned. 1090const char * 1091BaseRemoteGDB::hex2mem(char *vdst, const char *src, int maxlen) 1092{ 1093 char *dst = vdst; 1094 int msb, lsb; 1095 1096 while (*src && maxlen--) { 1097 msb = digit2i(*src++); 1098 if (msb < 0) 1099 return (src - 1); 1100 lsb = digit2i(*src++); 1101 if (lsb < 0) 1102 return (NULL); 1103 *dst++ = (msb << 4) | lsb; 1104 } 1105 return src; 1106} 1107 1108// Convert an hex string into an integer. 1109// This returns a pointer to the character following the last valid 1110// hex digit. 1111Addr 1112BaseRemoteGDB::hex2i(const char **srcp) 1113{ 1114 const char *src = *srcp; 1115 Addr r = 0; 1116 int nibble; 1117 1118 while ((nibble = digit2i(*src)) >= 0) { 1119 r *= 16; 1120 r += nibble; 1121 src++; 1122 } 1123 *srcp = src; 1124 return r; 1125} 1126 1127