remote_gdb.cc revision 12125:0066d9926c1a
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::processSingleStepEvent() 293{ 294 if (!singleStepEvent.scheduled()) 295 scheduleInstCommitEvent(&singleStepEvent, 1); 296 trap(SIGTRAP); 297} 298 299BaseRemoteGDB::BaseRemoteGDB(System *_system, ThreadContext *c) : 300 inputEvent(NULL), trapEvent(this), listener(NULL), number(-1), 301 fd(-1), active(false), attached(false), system(_system), 302 context(c), 303 singleStepEvent([this]{ processSingleStepEvent(); }, name()) 304{ 305} 306 307BaseRemoteGDB::~BaseRemoteGDB() 308{ 309 if (inputEvent) 310 delete inputEvent; 311} 312 313string 314BaseRemoteGDB::name() 315{ 316 return system->name() + ".remote_gdb"; 317} 318 319bool 320BaseRemoteGDB::isattached() 321{ return attached; } 322 323void 324BaseRemoteGDB::attach(int f) 325{ 326 fd = f; 327 328 inputEvent = new InputEvent(this, fd, POLLIN); 329 pollQueue.schedule(inputEvent); 330 331 attached = true; 332 DPRINTFN("remote gdb attached\n"); 333} 334 335void 336BaseRemoteGDB::detach() 337{ 338 attached = false; 339 active = false; 340 clearSingleStep(); 341 close(fd); 342 fd = -1; 343 344 pollQueue.remove(inputEvent); 345 DPRINTFN("remote gdb detached\n"); 346} 347 348///////////////////////// 349// 350// 351 352uint8_t 353BaseRemoteGDB::getbyte() 354{ 355 uint8_t b; 356 if (::read(fd, &b, sizeof(b)) == sizeof(b)) 357 return b; 358 359 throw BadClient("Couldn't read data from debugger."); 360} 361 362void 363BaseRemoteGDB::putbyte(uint8_t b) 364{ 365 if (::write(fd, &b, sizeof(b)) == sizeof(b)) 366 return; 367 368 throw BadClient("Couldn't write data to the debugger."); 369} 370 371// Send a packet to gdb 372void 373BaseRemoteGDB::send(const char *bp) 374{ 375 const char *p; 376 uint8_t csum, c; 377 378 DPRINTF(GDBSend, "send: %s\n", bp); 379 380 do { 381 p = bp; 382 // Start sending a packet 383 putbyte(GDBStart); 384 // Send the contents, and also keep a check sum. 385 for (csum = 0; (c = *p); p++) { 386 putbyte(c); 387 csum += c; 388 } 389 // Send the ending character. 390 putbyte(GDBEnd); 391 // Send the checksum. 392 putbyte(i2digit(csum >> 4)); 393 putbyte(i2digit(csum)); 394 // Try transmitting over and over again until the other end doesn't 395 // send an error back. 396 c = getbyte(); 397 } while ((c & 0x7f) == GDBBadP); 398} 399 400// Receive a packet from gdb 401int 402BaseRemoteGDB::recv(char *bp, int maxlen) 403{ 404 char *p; 405 uint8_t c; 406 int csum; 407 int len; 408 409 do { 410 p = bp; 411 csum = len = 0; 412 // Find the beginning of a packet 413 while ((c = getbyte()) != GDBStart); 414 415 // Read until you find the end of the data in the packet, and keep 416 // track of the check sum. 417 while (len < maxlen) { 418 c = getbyte(); 419 if (c == GDBEnd) 420 break; 421 c &= 0x7f; 422 csum += c; 423 *p++ = c; 424 len++; 425 } 426 427 // Mask the check sum, and terminate the command string. 428 csum &= 0xff; 429 *p = '\0'; 430 431 // If the command was too long, report an error. 432 if (len >= maxlen) { 433 putbyte(GDBBadP); 434 continue; 435 } 436 437 // Bring in the checksum. If the check sum matches, csum will be 0. 438 csum -= digit2i(getbyte()) * 16; 439 csum -= digit2i(getbyte()); 440 441 // If the check sum was correct 442 if (csum == 0) { 443 // Report that the packet was received correctly 444 putbyte(GDBGoodP); 445 // Sequence present? 446 if (bp[2] == ':') { 447 putbyte(bp[0]); 448 putbyte(bp[1]); 449 len -= 3; 450 memcpy(bp, bp+3, len); 451 } 452 break; 453 } 454 // Otherwise, report that there was a mistake. 455 putbyte(GDBBadP); 456 } while (1); 457 458 DPRINTF(GDBRecv, "recv: %s\n", bp); 459 460 return len; 461} 462 463// Read bytes from kernel address space for debugger. 464bool 465BaseRemoteGDB::read(Addr vaddr, size_t size, char *data) 466{ 467 static Addr lastaddr = 0; 468 static size_t lastsize = 0; 469 470 if (vaddr < 10) { 471 DPRINTF(GDBRead, "read: reading memory location zero!\n"); 472 vaddr = lastaddr + lastsize; 473 } 474 475 DPRINTF(GDBRead, "read: addr=%#x, size=%d", vaddr, size); 476 477 if (FullSystem) { 478 FSTranslatingPortProxy &proxy = context->getVirtProxy(); 479 proxy.readBlob(vaddr, (uint8_t*)data, size); 480 } else { 481 SETranslatingPortProxy &proxy = context->getMemProxy(); 482 proxy.readBlob(vaddr, (uint8_t*)data, size); 483 } 484 485#if TRACING_ON 486 if (DTRACE(GDBRead)) { 487 if (DTRACE(GDBExtra)) { 488 char buf[1024]; 489 mem2hex(buf, data, size); 490 DPRINTFNR(": %s\n", buf); 491 } else 492 DPRINTFNR("\n"); 493 } 494#endif 495 496 return true; 497} 498 499// Write bytes to kernel address space for debugger. 500bool 501BaseRemoteGDB::write(Addr vaddr, size_t size, const char *data) 502{ 503 static Addr lastaddr = 0; 504 static size_t lastsize = 0; 505 506 if (vaddr < 10) { 507 DPRINTF(GDBWrite, "write: writing memory location zero!\n"); 508 vaddr = lastaddr + lastsize; 509 } 510 511 if (DTRACE(GDBWrite)) { 512 DPRINTFN("write: addr=%#x, size=%d", vaddr, size); 513 if (DTRACE(GDBExtra)) { 514 char buf[1024]; 515 mem2hex(buf, data, size); 516 DPRINTFNR(": %s\n", buf); 517 } else 518 DPRINTFNR("\n"); 519 } 520 if (FullSystem) { 521 FSTranslatingPortProxy &proxy = context->getVirtProxy(); 522 proxy.writeBlob(vaddr, (uint8_t*)data, size); 523 } else { 524 SETranslatingPortProxy &proxy = context->getMemProxy(); 525 proxy.writeBlob(vaddr, (uint8_t*)data, size); 526 } 527 528 return true; 529} 530 531void 532BaseRemoteGDB::clearSingleStep() 533{ 534 descheduleInstCommitEvent(&singleStepEvent); 535} 536 537void 538BaseRemoteGDB::setSingleStep() 539{ 540 if (!singleStepEvent.scheduled()) 541 scheduleInstCommitEvent(&singleStepEvent, 1); 542} 543 544PCEventQueue *BaseRemoteGDB::getPcEventQueue() 545{ 546 return &system->pcEventQueue; 547} 548 549EventQueue * 550BaseRemoteGDB::getComInstEventQueue() 551{ 552 BaseCPU *cpu = context->getCpuPtr(); 553 return cpu->comInstEventQueue[context->threadId()]; 554} 555 556void 557BaseRemoteGDB::scheduleInstCommitEvent(Event *ev, int delta) 558{ 559 EventQueue *eq = getComInstEventQueue(); 560 // Here "ticks" aren't simulator ticks which measure time, they're 561 // instructions committed by the CPU. 562 eq->schedule(ev, eq->getCurTick() + delta); 563} 564 565void 566BaseRemoteGDB::descheduleInstCommitEvent(Event *ev) 567{ 568 if (ev->scheduled()) 569 getComInstEventQueue()->deschedule(ev); 570} 571 572bool 573BaseRemoteGDB::checkBpLen(size_t len) 574{ 575 return len == sizeof(MachInst); 576} 577 578BaseRemoteGDB::HardBreakpoint::HardBreakpoint(BaseRemoteGDB *_gdb, Addr pc) 579 : PCEvent(_gdb->getPcEventQueue(), "HardBreakpoint Event", pc), 580 gdb(_gdb), refcount(0) 581{ 582 DPRINTF(GDBMisc, "creating hardware breakpoint at %#x\n", evpc); 583} 584 585void 586BaseRemoteGDB::HardBreakpoint::process(ThreadContext *tc) 587{ 588 DPRINTF(GDBMisc, "handling hardware breakpoint at %#x\n", pc()); 589 590 if (tc == gdb->context) 591 gdb->trap(SIGTRAP); 592} 593 594void 595BaseRemoteGDB::insertSoftBreak(Addr addr, size_t len) 596{ 597 if (!checkBpLen(len)) 598 throw BadClient("Invalid breakpoint length\n"); 599 600 return insertHardBreak(addr, len); 601} 602 603void 604BaseRemoteGDB::removeSoftBreak(Addr addr, size_t len) 605{ 606 if (!checkBpLen(len)) 607 throw BadClient("Invalid breakpoint length.\n"); 608 609 return removeHardBreak(addr, len); 610} 611 612void 613BaseRemoteGDB::insertHardBreak(Addr addr, size_t len) 614{ 615 if (!checkBpLen(len)) 616 throw BadClient("Invalid breakpoint length\n"); 617 618 DPRINTF(GDBMisc, "Inserting hardware breakpoint at %#x\n", addr); 619 620 HardBreakpoint *&bkpt = hardBreakMap[addr]; 621 if (bkpt == 0) 622 bkpt = new HardBreakpoint(this, addr); 623 624 bkpt->refcount++; 625} 626 627void 628BaseRemoteGDB::removeHardBreak(Addr addr, size_t len) 629{ 630 if (!checkBpLen(len)) 631 throw BadClient("Invalid breakpoint length\n"); 632 633 DPRINTF(GDBMisc, "Removing hardware breakpoint at %#x\n", addr); 634 635 break_iter_t i = hardBreakMap.find(addr); 636 if (i == hardBreakMap.end()) 637 throw CmdError("E0C"); 638 639 HardBreakpoint *hbp = (*i).second; 640 if (--hbp->refcount == 0) { 641 delete hbp; 642 hardBreakMap.erase(i); 643 } 644} 645 646void 647BaseRemoteGDB::setTempBreakpoint(Addr bkpt) 648{ 649 DPRINTF(GDBMisc, "setTempBreakpoint: addr=%#x\n", bkpt); 650 insertHardBreak(bkpt, sizeof(TheISA::MachInst)); 651} 652 653void 654BaseRemoteGDB::clearTempBreakpoint(Addr &bkpt) 655{ 656 DPRINTF(GDBMisc, "setTempBreakpoint: addr=%#x\n", bkpt); 657 removeHardBreak(bkpt, sizeof(TheISA::MachInst)); 658 bkpt = 0; 659} 660 661enum GdbBreakpointType { 662 GdbSoftBp = '0', 663 GdbHardBp = '1', 664 GdbWriteWp = '2', 665 GdbReadWp = '3', 666 GdbAccWp = '4', 667}; 668 669const char * 670BaseRemoteGDB::break_type(char c) 671{ 672 switch(c) { 673 case GdbSoftBp: return "software breakpoint"; 674 case GdbHardBp: return "hardware breakpoint"; 675 case GdbWriteWp: return "write watchpoint"; 676 case GdbReadWp: return "read watchpoint"; 677 case GdbAccWp: return "access watchpoint"; 678 default: return "unknown breakpoint/watchpoint"; 679 } 680} 681 682std::map<char, GdbCommand> BaseRemoteGDB::command_map = { 683 // last signal 684 { '?', { "KGDB_SIGNAL", &BaseRemoteGDB::cmd_signal } }, 685 // set baud (deprecated) 686 { 'b', { "KGDB_SET_BAUD", &BaseRemoteGDB::cmd_unsupported } }, 687 // set breakpoint (deprecated) 688 { 'B', { "KGDB_SET_BREAK", &BaseRemoteGDB::cmd_unsupported } }, 689 // resume 690 { 'c', { "KGDB_CONT", &BaseRemoteGDB::cmd_cont } }, 691 // continue with signal 692 { 'C', { "KGDB_ASYNC_CONT", &BaseRemoteGDB::cmd_async_cont } }, 693 // toggle debug flags (deprecated) 694 { 'd', { "KGDB_DEBUG", &BaseRemoteGDB::cmd_unsupported } }, 695 // detach remote gdb 696 { 'D', { "KGDB_DETACH", &BaseRemoteGDB::cmd_detach } }, 697 // read general registers 698 { 'g', { "KGDB_REG_R", &BaseRemoteGDB::cmd_reg_r } }, 699 // write general registers 700 { 'G', { "KGDB_REG_W", &BaseRemoteGDB::cmd_reg_w } }, 701 // set thread 702 { 'H', { "KGDB_SET_THREAD", &BaseRemoteGDB::cmd_set_thread } }, 703 // step a single cycle 704 { 'i', { "KGDB_CYCLE_STEP", &BaseRemoteGDB::cmd_unsupported } }, 705 // signal then cycle step 706 { 'I', { "KGDB_SIG_CYCLE_STEP", &BaseRemoteGDB::cmd_unsupported } }, 707 // kill program 708 { 'k', { "KGDB_KILL", &BaseRemoteGDB::cmd_detach } }, 709 // read memory 710 { 'm', { "KGDB_MEM_R", &BaseRemoteGDB::cmd_mem_r } }, 711 // write memory 712 { 'M', { "KGDB_MEM_W", &BaseRemoteGDB::cmd_mem_w } }, 713 // read register 714 { 'p', { "KGDB_READ_REG", &BaseRemoteGDB::cmd_unsupported } }, 715 // write register 716 { 'P', { "KGDB_SET_REG", &BaseRemoteGDB::cmd_unsupported } }, 717 // query variable 718 { 'q', { "KGDB_QUERY_VAR", &BaseRemoteGDB::cmd_query_var } }, 719 // set variable 720 { 'Q', { "KGDB_SET_VAR", &BaseRemoteGDB::cmd_unsupported } }, 721 // reset system (deprecated) 722 { 'r', { "KGDB_RESET", &BaseRemoteGDB::cmd_unsupported } }, 723 // step 724 { 's', { "KGDB_STEP", &BaseRemoteGDB::cmd_step } }, 725 // signal and step 726 { 'S', { "KGDB_ASYNC_STEP", &BaseRemoteGDB::cmd_async_step } }, 727 // find out if the thread is alive 728 { 'T', { "KGDB_THREAD_ALIVE", &BaseRemoteGDB::cmd_unsupported } }, 729 // target exited 730 { 'W', { "KGDB_TARGET_EXIT", &BaseRemoteGDB::cmd_unsupported } }, 731 // write memory 732 { 'X', { "KGDB_BINARY_DLOAD", &BaseRemoteGDB::cmd_unsupported } }, 733 // remove breakpoint or watchpoint 734 { 'z', { "KGDB_CLR_HW_BKPT", &BaseRemoteGDB::cmd_clr_hw_bkpt } }, 735 // insert breakpoint or watchpoint 736 { 'Z', { "KGDB_SET_HW_BKPT", &BaseRemoteGDB::cmd_set_hw_bkpt } }, 737}; 738 739 740bool 741BaseRemoteGDB::cmd_unsupported(GdbCommand::Context &ctx) 742{ 743 DPRINTF(GDBMisc, "Unsupported command: %s\n", ctx.cmd->name); 744 DDUMP(GDBMisc, ctx.data, ctx.len); 745 throw Unsupported(); 746} 747 748 749bool 750BaseRemoteGDB::cmd_signal(GdbCommand::Context &ctx) 751{ 752 send(csprintf("S%02x", ctx.type).c_str()); 753 return true; 754} 755 756bool 757BaseRemoteGDB::cmd_cont(GdbCommand::Context &ctx) 758{ 759 const char *p = ctx.data; 760 if (ctx.len) { 761 Addr newPc = hex2i(&p); 762 context->pcState(newPc); 763 } 764 clearSingleStep(); 765 return false; 766} 767 768bool 769BaseRemoteGDB::cmd_async_cont(GdbCommand::Context &ctx) 770{ 771 const char *p = ctx.data; 772 hex2i(&p); 773 if (*p++ == ';') { 774 Addr newPc = hex2i(&p); 775 context->pcState(newPc); 776 } 777 clearSingleStep(); 778 return false; 779} 780 781bool 782BaseRemoteGDB::cmd_detach(GdbCommand::Context &ctx) 783{ 784 detach(); 785 return false; 786} 787 788bool 789BaseRemoteGDB::cmd_reg_r(GdbCommand::Context &ctx) 790{ 791 char buf[2 * regCachePtr->size() + 1]; 792 buf[2 * regCachePtr->size()] = '\0'; 793 mem2hex(buf, regCachePtr->data(), regCachePtr->size()); 794 send(buf); 795 return true; 796} 797 798bool 799BaseRemoteGDB::cmd_reg_w(GdbCommand::Context &ctx) 800{ 801 const char *p = ctx.data; 802 p = hex2mem(regCachePtr->data(), p, regCachePtr->size()); 803 if (p == NULL || *p != '\0') 804 throw CmdError("E01"); 805 806 regCachePtr->setRegs(context); 807 send("OK"); 808 809 return true; 810} 811 812bool 813BaseRemoteGDB::cmd_set_thread(GdbCommand::Context &ctx) 814{ 815 const char *p = ctx.data + 1; // Ignore the subcommand byte. 816 if (hex2i(&p) != 0) 817 throw CmdError("E01"); 818 send("OK"); 819 return true; 820} 821 822bool 823BaseRemoteGDB::cmd_mem_r(GdbCommand::Context &ctx) 824{ 825 const char *p = ctx.data; 826 Addr addr = hex2i(&p); 827 if (*p++ != ',') 828 throw CmdError("E02"); 829 size_t len = hex2i(&p); 830 if (*p != '\0') 831 throw CmdError("E03"); 832 if (!acc(addr, len)) 833 throw CmdError("E05"); 834 835 char buf[len]; 836 if (!read(addr, len, buf)) 837 throw CmdError("E05"); 838 839 char temp[2 * len + 1]; 840 temp[2 * len] = '\0'; 841 mem2hex(temp, buf, len); 842 send(temp); 843 return true; 844} 845 846bool 847BaseRemoteGDB::cmd_mem_w(GdbCommand::Context &ctx) 848{ 849 const char *p = ctx.data; 850 Addr addr = hex2i(&p); 851 if (*p++ != ',') 852 throw CmdError("E06"); 853 size_t len = hex2i(&p); 854 if (*p++ != ':') 855 throw CmdError("E07"); 856 if (len * 2 > ctx.len - (p - ctx.data)) 857 throw CmdError("E08"); 858 char buf[len]; 859 p = (char *)hex2mem(buf, p, len); 860 if (p == NULL) 861 throw CmdError("E09"); 862 if (!acc(addr, len)) 863 throw CmdError("E0A"); 864 if (!write(addr, len, buf)) 865 throw CmdError("E0B"); 866 send("OK"); 867 return true; 868} 869 870bool 871BaseRemoteGDB::cmd_query_var(GdbCommand::Context &ctx) 872{ 873 if (string(ctx.data, ctx.len - 1) != "C") 874 throw Unsupported(); 875 send("QC0"); 876 return true; 877} 878 879bool 880BaseRemoteGDB::cmd_async_step(GdbCommand::Context &ctx) 881{ 882 const char *p = ctx.data; 883 hex2i(&p); // Ignore the subcommand byte. 884 if (*p++ == ';') { 885 Addr newPc = hex2i(&p); 886 context->pcState(newPc); 887 } 888 setSingleStep(); 889 return false; 890} 891 892bool 893BaseRemoteGDB::cmd_step(GdbCommand::Context &ctx) 894{ 895 if (ctx.len) { 896 const char *p = ctx.data; 897 Addr newPc = hex2i(&p); 898 context->pcState(newPc); 899 } 900 setSingleStep(); 901 return false; 902} 903 904bool 905BaseRemoteGDB::cmd_clr_hw_bkpt(GdbCommand::Context &ctx) 906{ 907 const char *p = ctx.data; 908 char subcmd = *p++; 909 if (*p++ != ',') 910 throw CmdError("E0D"); 911 Addr addr = hex2i(&p); 912 if (*p++ != ',') 913 throw CmdError("E0D"); 914 size_t len = hex2i(&p); 915 916 DPRINTF(GDBMisc, "clear %s, addr=%#x, len=%d\n", 917 break_type(subcmd), addr, len); 918 919 switch (subcmd) { 920 case GdbSoftBp: 921 removeSoftBreak(addr, len); 922 break; 923 case GdbHardBp: 924 removeHardBreak(addr, len); 925 break; 926 case GdbWriteWp: 927 case GdbReadWp: 928 case GdbAccWp: 929 default: // unknown 930 throw Unsupported(); 931 } 932 send("OK"); 933 934 return true; 935} 936 937bool 938BaseRemoteGDB::cmd_set_hw_bkpt(GdbCommand::Context &ctx) 939{ 940 const char *p = ctx.data; 941 char subcmd = *p++; 942 if (*p++ != ',') 943 throw CmdError("E0D"); 944 Addr addr = hex2i(&p); 945 if (*p++ != ',') 946 throw CmdError("E0D"); 947 size_t len = hex2i(&p); 948 949 DPRINTF(GDBMisc, "set %s, addr=%#x, len=%d\n", 950 break_type(subcmd), addr, len); 951 952 switch (subcmd) { 953 case GdbSoftBp: 954 insertSoftBreak(addr, len); 955 break; 956 case GdbHardBp: 957 insertHardBreak(addr, len); 958 break; 959 case GdbWriteWp: 960 case GdbReadWp: 961 case GdbAccWp: 962 default: // unknown 963 throw Unsupported(); 964 } 965 send("OK"); 966 967 return true; 968} 969 970 971// This function does all command processing for interfacing to a 972// remote gdb. Note that the error codes are ignored by gdb at 973// present, but might eventually become meaningful. (XXX) It might 974// makes sense to use POSIX errno values, because that is what the 975// gdb/remote.c functions want to return. 976bool 977BaseRemoteGDB::trap(int type) 978{ 979 980 if (!attached) 981 return false; 982 983 DPRINTF(GDBMisc, "trap: PC=%s\n", context->pcState()); 984 985 clearSingleStep(); 986 987 /* 988 * The first entry to this function is normally through 989 * a breakpoint trap in kgdb_connect(), in which case we 990 * must advance past the breakpoint because gdb will not. 991 * 992 * On the first entry here, we expect that gdb is not yet 993 * listening to us, so just enter the interaction loop. 994 * After the debugger is "active" (connected) it will be 995 * waiting for a "signaled" message from us. 996 */ 997 if (!active) { 998 active = true; 999 } else { 1000 // Tell remote host that an exception has occurred. 1001 send(csprintf("S%02x", type).c_str()); 1002 } 1003 1004 // Stick frame regs into our reg cache. 1005 regCachePtr = gdbRegs(); 1006 regCachePtr->getRegs(context); 1007 1008 char data[GDBPacketBufLen + 1]; 1009 GdbCommand::Context cmdCtx; 1010 cmdCtx.type = type; 1011 cmdCtx.data = &data[1]; 1012 1013 for (;;) { 1014 try { 1015 size_t datalen = recv(data, sizeof(data)); 1016 if (datalen < 1) 1017 throw BadClient(); 1018 1019 data[datalen] = 0; // Sentinel 1020 cmdCtx.cmd_byte = data[0]; 1021 cmdCtx.len = datalen - 1; 1022 1023 auto cmdIt = command_map.find(cmdCtx.cmd_byte); 1024 if (cmdIt == command_map.end()) { 1025 DPRINTF(GDBMisc, "Unknown command: %c(%#x)\n", 1026 cmdCtx.cmd_byte, cmdCtx.cmd_byte); 1027 throw Unsupported(); 1028 } 1029 cmdCtx.cmd = &(cmdIt->second); 1030 1031 if (!(this->*(cmdCtx.cmd->func))(cmdCtx)) 1032 break; 1033 1034 } catch (BadClient &e) { 1035 if (e.warning) 1036 warn(e.warning); 1037 detach(); 1038 break; 1039 } catch (Unsupported &e) { 1040 send(""); 1041 } catch (CmdError &e) { 1042 send(e.error.c_str()); 1043 } catch (...) { 1044 panic("Unrecognzied GDB exception."); 1045 } 1046 } 1047 1048 return true; 1049} 1050 1051// Convert a hex digit into an integer. 1052// This returns -1 if the argument passed is no valid hex digit. 1053int 1054BaseRemoteGDB::digit2i(char c) 1055{ 1056 if (c >= '0' && c <= '9') 1057 return (c - '0'); 1058 else if (c >= 'a' && c <= 'f') 1059 return (c - 'a' + 10); 1060 else if (c >= 'A' && c <= 'F') 1061 return (c - 'A' + 10); 1062 else 1063 return (-1); 1064} 1065 1066// Convert the low 4 bits of an integer into an hex digit. 1067char 1068BaseRemoteGDB::i2digit(int n) 1069{ 1070 return ("0123456789abcdef"[n & 0x0f]); 1071} 1072 1073// Convert a byte array into an hex string. 1074void 1075BaseRemoteGDB::mem2hex(char *vdst, const char *vsrc, int len) 1076{ 1077 char *dst = vdst; 1078 const char *src = vsrc; 1079 1080 while (len--) { 1081 *dst++ = i2digit(*src >> 4); 1082 *dst++ = i2digit(*src++); 1083 } 1084 *dst = '\0'; 1085} 1086 1087// Convert an hex string into a byte array. 1088// This returns a pointer to the character following the last valid 1089// hex digit. If the string ends in the middle of a byte, NULL is 1090// returned. 1091const char * 1092BaseRemoteGDB::hex2mem(char *vdst, const char *src, int maxlen) 1093{ 1094 char *dst = vdst; 1095 int msb, lsb; 1096 1097 while (*src && maxlen--) { 1098 msb = digit2i(*src++); 1099 if (msb < 0) 1100 return (src - 1); 1101 lsb = digit2i(*src++); 1102 if (lsb < 0) 1103 return (NULL); 1104 *dst++ = (msb << 4) | lsb; 1105 } 1106 return src; 1107} 1108 1109// Convert an hex string into an integer. 1110// This returns a pointer to the character following the last valid 1111// hex digit. 1112Addr 1113BaseRemoteGDB::hex2i(const char **srcp) 1114{ 1115 const char *src = *srcp; 1116 Addr r = 0; 1117 int nibble; 1118 1119 while ((nibble = digit2i(*src)) >= 0) { 1120 r *= 16; 1121 r += nibble; 1122 src++; 1123 } 1124 *srcp = src; 1125 return r; 1126} 1127