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
150#ifndef NDEBUG
151vector<BaseRemoteGDB *> debuggers;
152
153void
154debugger()
155{
156 static int current_debugger = -1;
157 if (current_debugger >= 0 && current_debugger < (int)debuggers.size()) {
158 BaseRemoteGDB *gdb = debuggers[current_debugger];
159 if (!gdb->isattached())
160 gdb->listener->accept();
161 if (gdb->isattached())
162 gdb->trap(SIGILL);
163 }
164}
165#endif
166
167///////////////////////////////////////////////////////////
168//
169//
170//
171
172GDBListener::InputEvent::InputEvent(GDBListener *l, int fd, int e)
173 : PollEvent(fd, e), listener(l)
174{}
175
176void
177GDBListener::InputEvent::process(int revent)
178{
179 listener->accept();
180}
181
182GDBListener::GDBListener(BaseRemoteGDB *g, int p)
183 : inputEvent(NULL), gdb(g), port(p)
184{
185 assert(!gdb->listener);
186 gdb->listener = this;
187}
188
189GDBListener::~GDBListener()
190{
191 if (inputEvent)
192 delete inputEvent;
193}
194
195string
196GDBListener::name()
197{
198 return gdb->name() + ".listener";
199}
200
201void
202GDBListener::listen()
203{
204 if (ListenSocket::allDisabled()) {
205 warn_once("Sockets disabled, not accepting gdb connections");
206 return;
207 }
208
209 while (!listener.listen(port, true)) {
210 DPRINTF(GDBMisc, "Can't bind port %d\n", port);
211 port++;
212 }
213
214 inputEvent = new InputEvent(this, listener.getfd(), POLLIN);
215 pollQueue.schedule(inputEvent);
216
217#ifndef NDEBUG
218 gdb->number = debuggers.size();
219 debuggers.push_back(gdb);
220#endif
221
222#ifndef NDEBUG
223 ccprintf(cerr, "%d: %s: listening for remote gdb #%d on port %d\n",
224 curTick(), name(), gdb->number, port);
225#else
226 ccprintf(cerr, "%d: %s: listening for remote gdb on port %d\n",
227 curTick(), name(), port);
228#endif
229}
230
231void
232GDBListener::accept()
233{
234 if (!listener.islistening())
235 panic("GDBListener::accept(): cannot accept if we're not listening!");
236
237 int sfd = listener.accept(true);
238
239 if (sfd != -1) {
240 if (gdb->isattached())
241 close(sfd);
242 else
243 gdb->attach(sfd);
244 }
245}
246
247BaseRemoteGDB::InputEvent::InputEvent(BaseRemoteGDB *g, int fd, int e)
248 : PollEvent(fd, e), gdb(g)
249{}
250
251void
252BaseRemoteGDB::InputEvent::process(int revent)
253{
254 if (gdb->trapEvent.scheduled()) {
255 warn("GDB trap event has already been scheduled! "
256 "Ignoring this input event.");
257 return;
258 }
259
260 if (revent & POLLIN) {
261 gdb->trapEvent.type(SIGILL);
262 gdb->scheduleInstCommitEvent(&gdb->trapEvent, 0);
263 } else if (revent & POLLNVAL) {
264 gdb->descheduleInstCommitEvent(&gdb->trapEvent);
265 gdb->detach();
266 }
267}
268
269void
270BaseRemoteGDB::TrapEvent::process()
271{
272 gdb->trap(_type);
273}
274
275void
276BaseRemoteGDB::SingleStepEvent::process()
277{
278 if (!gdb->singleStepEvent.scheduled())
279 gdb->scheduleInstCommitEvent(&gdb->singleStepEvent, 1);
280 gdb->trap(SIGTRAP);
281}
282
283BaseRemoteGDB::BaseRemoteGDB(System *_system, ThreadContext *c) :
284 inputEvent(NULL), trapEvent(this), listener(NULL),
285 number(-1), fd(-1), active(false), attached(false), system(_system),
286 context(c), singleStepEvent(this)
287{
288}
289
290BaseRemoteGDB::~BaseRemoteGDB()
291{
292 if (inputEvent)
293 delete inputEvent;
294}
295
296string
297BaseRemoteGDB::name()
298{
299 return system->name() + ".remote_gdb";
300}
301
302bool
303BaseRemoteGDB::isattached()
304{ return attached; }
305
306void
307BaseRemoteGDB::attach(int f)
308{
309 fd = f;
310
311 inputEvent = new InputEvent(this, fd, POLLIN);
312 pollQueue.schedule(inputEvent);
313
314 attached = true;
315 DPRINTFN("remote gdb attached\n");
316}
317
318void
319BaseRemoteGDB::detach()
320{
321 attached = false;
322 close(fd);
323 fd = -1;
324
325 pollQueue.remove(inputEvent);
326 DPRINTFN("remote gdb detached\n");
327}
328
329const char *
330BaseRemoteGDB::gdb_command(char cmd)
331{
332 switch (cmd) {
333 case GDBSignal: return "KGDB_SIGNAL";
334 case GDBSetBaud: return "KGDB_SET_BAUD";
335 case GDBSetBreak: return "KGDB_SET_BREAK";
336 case GDBCont: return "KGDB_CONT";
337 case GDBAsyncCont: return "KGDB_ASYNC_CONT";
338 case GDBDebug: return "KGDB_DEBUG";
339 case GDBDetach: return "KGDB_DETACH";
340 case GDBRegR: return "KGDB_REG_R";
341 case GDBRegW: return "KGDB_REG_W";
342 case GDBSetThread: return "KGDB_SET_THREAD";
343 case GDBCycleStep: return "KGDB_CYCLE_STEP";
344 case GDBSigCycleStep: return "KGDB_SIG_CYCLE_STEP";
345 case GDBKill: return "KGDB_KILL";
346 case GDBMemW: return "KGDB_MEM_W";
347 case GDBMemR: return "KGDB_MEM_R";
348 case GDBSetReg: return "KGDB_SET_REG";
349 case GDBReadReg: return "KGDB_READ_REG";
350 case GDBQueryVar: return "KGDB_QUERY_VAR";
351 case GDBSetVar: return "KGDB_SET_VAR";
352 case GDBReset: return "KGDB_RESET";
353 case GDBStep: return "KGDB_STEP";
354 case GDBAsyncStep: return "KGDB_ASYNC_STEP";
355 case GDBThreadAlive: return "KGDB_THREAD_ALIVE";
356 case GDBTargetExit: return "KGDB_TARGET_EXIT";
357 case GDBBinaryDload: return "KGDB_BINARY_DLOAD";
358 case GDBClrHwBkpt: return "KGDB_CLR_HW_BKPT";
359 case GDBSetHwBkpt: return "KGDB_SET_HW_BKPT";
360 case GDBStart: return "KGDB_START";
361 case GDBEnd: return "KGDB_END";
362 case GDBGoodP: return "KGDB_GOODP";
363 case GDBBadP: return "KGDB_BADP";
364 default: return "KGDB_UNKNOWN";
365 }
366}
367
368/////////////////////////
369//
370//
371
372bool
373BaseRemoteGDB::getbyte(uint8_t &b)
374{
375 if (::read(fd, &b, sizeof(b)) == sizeof(b)) {
376 return true;
377 } else {
378 warn("Couldn't read data from debugger, detaching.");
379 detach();
380 return false;
381 }
382}
383
384bool
385BaseRemoteGDB::putbyte(uint8_t b)
386{
387 if (::write(fd, &b, sizeof(b)) == sizeof(b)) {
388 return true;
389 } else {
390 warn("Couldn't write data to the debugger, detaching.");
391 detach();
392 return false;
393 }
394}
395
396// Send a packet to gdb
397ssize_t
398BaseRemoteGDB::send(const char *bp)
399{
400 const char *p;
401 uint8_t csum, c;
402
403 DPRINTF(GDBSend, "send: %s\n", bp);
404
405 do {
406 p = bp;
407 //Start sending a packet
408 if (!putbyte(GDBStart))
409 return -1;
410 //Send the contents, and also keep a check sum.
411 for (csum = 0; (c = *p); p++) {
412 if (!putbyte(c))
413 return -1;
414 csum += c;
415 }
416 if (//Send the ending character.
417 !putbyte(GDBEnd) ||
418 //Sent the checksum.
419 !putbyte(i2digit(csum >> 4)) ||
420 !putbyte(i2digit(csum))) {
421 return -1;
422 }
423 //Try transmitting over and over again until the other end doesn't
424 //send an error back.
425 if (!getbyte(c))
426 return -1;
427 } while ((c & 0x7f) == GDBBadP);
428 return 0;
429}
430
431// Receive a packet from gdb
432int
433BaseRemoteGDB::recv(char *bp, int maxlen)
434{
435 char *p;
436 uint8_t c;
437 int csum;
438 int len;
439
440 do {
441 p = bp;
442 csum = len = 0;
443 //Find the beginning of a packet
444 do {
445 if (!getbyte(c))
446 return -1;
447 } while (c != GDBStart);
448
449 //Read until you find the end of the data in the packet, and keep
450 //track of the check sum.
451 while (len < maxlen) {
452 if (!getbyte(c))
453 return -1;
454 if (c == GDBEnd)
455 break;
456 c &= 0x7f;
457 csum += c;
458 *p++ = c;
459 len++;
460 }
461
462 //Mask the check sum, and terminate the command string.
463 csum &= 0xff;
464 *p = '\0';
465
466 //If the command was too long, report an error.
467 if (len >= maxlen) {
468 if (!putbyte(GDBBadP))
469 return -1;
470 continue;
471 }
472
473 //Bring in the checksum. If the check sum matches, csum will be 0.
474 uint8_t csum1, csum2;
475 if (!getbyte(csum1) || !getbyte(csum2))
476 return -1;
477 csum -= digit2i(csum1) * 16;
478 csum -= digit2i(csum2);
479
480 //If the check sum was correct
481 if (csum == 0) {
482 //Report that the packet was received correctly
483 if (!putbyte(GDBGoodP))
484 return -1;
485 // Sequence present?
486 if (bp[2] == ':') {
487 if (!putbyte(bp[0]) || !putbyte(bp[1]))
488 return -1;
489 len -= 3;
490 memcpy(bp, bp+3, len);
491 }
492 break;
493 }
494 //Otherwise, report that there was a mistake.
495 if (!putbyte(GDBBadP))
496 return -1;
497 } while (1);
498
499 DPRINTF(GDBRecv, "recv: %s: %s\n", gdb_command(*bp), bp);
500
501 return (len);
502}
503
504// Read bytes from kernel address space for debugger.
505bool
506BaseRemoteGDB::read(Addr vaddr, size_t size, char *data)
507{
508 static Addr lastaddr = 0;
509 static size_t lastsize = 0;
510
511 if (vaddr < 10) {
512 DPRINTF(GDBRead, "read: reading memory location zero!\n");
513 vaddr = lastaddr + lastsize;
514 }
515
516 DPRINTF(GDBRead, "read: addr=%#x, size=%d", vaddr, size);
517
518 if (FullSystem) {
519 FSTranslatingPortProxy &proxy = context->getVirtProxy();
520 proxy.readBlob(vaddr, (uint8_t*)data, size);
521 } else {
522 SETranslatingPortProxy &proxy = context->getMemProxy();
523 proxy.readBlob(vaddr, (uint8_t*)data, size);
524 }
525
526#if TRACING_ON
527 if (DTRACE(GDBRead)) {
528 if (DTRACE(GDBExtra)) {
529 char buf[1024];
530 mem2hex(buf, data, size);
531 DPRINTFNR(": %s\n", buf);
532 } else
533 DPRINTFNR("\n");
534 }
535#endif
536
537 return true;
538}
539
540// Write bytes to kernel address space for debugger.
541bool
542BaseRemoteGDB::write(Addr vaddr, size_t size, const char *data)
543{
544 static Addr lastaddr = 0;
545 static size_t lastsize = 0;
546
547 if (vaddr < 10) {
548 DPRINTF(GDBWrite, "write: writing memory location zero!\n");
549 vaddr = lastaddr + lastsize;
550 }
551
552 if (DTRACE(GDBWrite)) {
553 DPRINTFN("write: addr=%#x, size=%d", vaddr, size);
554 if (DTRACE(GDBExtra)) {
555 char buf[1024];
556 mem2hex(buf, data, size);
557 DPRINTFNR(": %s\n", buf);
558 } else
559 DPRINTFNR("\n");
560 }
561 if (FullSystem) {
562 FSTranslatingPortProxy &proxy = context->getVirtProxy();
563 proxy.writeBlob(vaddr, (uint8_t*)data, size);
564 } else {
565 SETranslatingPortProxy &proxy = context->getMemProxy();
566 proxy.writeBlob(vaddr, (uint8_t*)data, size);
567 }
568
569 return true;
570}
571
572void
573BaseRemoteGDB::clearSingleStep()
574{
575 descheduleInstCommitEvent(&singleStepEvent);
576}
577
578void
579BaseRemoteGDB::setSingleStep()
580{
581 if (!singleStepEvent.scheduled())
582 scheduleInstCommitEvent(&singleStepEvent, 1);
583}
584
585PCEventQueue *BaseRemoteGDB::getPcEventQueue()
586{
587 return &system->pcEventQueue;
588}
589
590EventQueue *
591BaseRemoteGDB::getComInstEventQueue()
592{
593 BaseCPU *cpu = context->getCpuPtr();
594 return cpu->comInstEventQueue[context->threadId()];
595}
596
597void
598BaseRemoteGDB::scheduleInstCommitEvent(Event *ev, int delta)
599{
600 EventQueue *eq = getComInstEventQueue();
601 // Here "ticks" aren't simulator ticks which measure time, they're
602 // instructions committed by the CPU.
603 eq->schedule(ev, eq->getCurTick() + delta);
604}
605
606void
607BaseRemoteGDB::descheduleInstCommitEvent(Event *ev)
608{
609 if (ev->scheduled())
610 getComInstEventQueue()->deschedule(ev);
611}
612
613bool
614BaseRemoteGDB::checkBpLen(size_t len)
615{
616 return len == sizeof(MachInst);
617}
618
619BaseRemoteGDB::HardBreakpoint::HardBreakpoint(BaseRemoteGDB *_gdb, Addr pc)
620 : PCEvent(_gdb->getPcEventQueue(), "HardBreakpoint Event", pc),
621 gdb(_gdb), refcount(0)
622{
623 DPRINTF(GDBMisc, "creating hardware breakpoint at %#x\n", evpc);
624}
625
626void
627BaseRemoteGDB::HardBreakpoint::process(ThreadContext *tc)
628{
629 DPRINTF(GDBMisc, "handling hardware breakpoint at %#x\n", pc());
630
631 if (tc == gdb->context)
632 gdb->trap(SIGTRAP);
633}
634
635bool
636BaseRemoteGDB::insertSoftBreak(Addr addr, size_t len)
637{
638 if (!checkBpLen(len))
639 panic("invalid length\n");
640
641 return insertHardBreak(addr, len);
642}
643
644bool
645BaseRemoteGDB::removeSoftBreak(Addr addr, size_t len)
646{
647 if (!checkBpLen(len))
648 panic("invalid length\n");
649
650 return removeHardBreak(addr, len);
651}
652
653bool
654BaseRemoteGDB::insertHardBreak(Addr addr, size_t len)
655{
656 if (!checkBpLen(len))
657 panic("invalid length\n");
658
659 DPRINTF(GDBMisc, "inserting hardware breakpoint at %#x\n", addr);
660
661 HardBreakpoint *&bkpt = hardBreakMap[addr];
662 if (bkpt == 0)
663 bkpt = new HardBreakpoint(this, addr);
664
665 bkpt->refcount++;
666
667 return true;
668}
669
670bool
671BaseRemoteGDB::removeHardBreak(Addr addr, size_t len)
672{
673 if (!checkBpLen(len))
674 panic("invalid length\n");
675
676 DPRINTF(GDBMisc, "removing hardware breakpoint at %#x\n", addr);
677
678 break_iter_t i = hardBreakMap.find(addr);
679 if (i == hardBreakMap.end())
680 return false;
681
682 HardBreakpoint *hbp = (*i).second;
683 if (--hbp->refcount == 0) {
684 delete hbp;
685 hardBreakMap.erase(i);
686 }
687
688 return true;
689}
690
691void
692BaseRemoteGDB::setTempBreakpoint(Addr bkpt)
693{
694 DPRINTF(GDBMisc, "setTempBreakpoint: addr=%#x\n", bkpt);
695 insertHardBreak(bkpt, sizeof(TheISA::MachInst));
696}
697
698void
699BaseRemoteGDB::clearTempBreakpoint(Addr &bkpt)
700{
701 DPRINTF(GDBMisc, "setTempBreakpoint: addr=%#x\n", bkpt);
702 removeHardBreak(bkpt, sizeof(TheISA::MachInst));
703 bkpt = 0;
704}
705
706const char *
707BaseRemoteGDB::break_type(char c)
708{
709 switch(c) {
710 case '0': return "software breakpoint";
711 case '1': return "hardware breakpoint";
712 case '2': return "write watchpoint";
713 case '3': return "read watchpoint";
714 case '4': return "access watchpoint";
715 default: return "unknown breakpoint/watchpoint";
716 }
717}
718
719// This function does all command processing for interfacing to a
720// remote gdb. Note that the error codes are ignored by gdb at
721// present, but might eventually become meaningful. (XXX) It might
722// makes sense to use POSIX errno values, because that is what the
723// gdb/remote.c functions want to return.
724bool
725BaseRemoteGDB::trap(int type)
726{
727 uint64_t val;
728 size_t datalen, len;
729 char data[GDBPacketBufLen + 1];
730 size_t bufferSize;
731 const char *p;
732 char command, subcmd;
733 string var;
734 bool ret;
735
736 if (!attached)
737 return false;
738
739 unique_ptr<BaseRemoteGDB::BaseGdbRegCache> regCache(gdbRegs());
740
741 bufferSize = regCache->size() * 2 + 256;
742 unique_ptr<char[]> buffer_mem(new char[bufferSize]);
743 char *buffer = buffer_mem.get();
744
745 DPRINTF(GDBMisc, "trap: PC=%s\n", context->pcState());
746
747 clearSingleStep();
748
749 /*
750 * The first entry to this function is normally through
751 * a breakpoint trap in kgdb_connect(), in which case we
752 * must advance past the breakpoint because gdb will not.
753 *
754 * On the first entry here, we expect that gdb is not yet
755 * listening to us, so just enter the interaction loop.
756 * After the debugger is "active" (connected) it will be
757 * waiting for a "signaled" message from us.
758 */
759 if (!active) {
760 active = true;
761 } else {
762 // Tell remote host that an exception has occurred.
763 snprintf(buffer, bufferSize, "S%02x", type);
764 if (send(buffer) < 0)
765 return true;
766 }
767
768 // Stick frame regs into our reg cache.
769 regCache->getRegs(context);
770
771 for (;;) {
772 int recved = recv(data, sizeof(data));
773 if (recved < 0)
774 return true;
775 datalen = recved;
776 data[sizeof(data) - 1] = 0; // Sentinel
777 command = data[0];
778 subcmd = 0;
779 p = data + 1;
780 switch (command) {
781
782 case GDBSignal:
783 // if this command came from a running gdb, answer it --
784 // the other guy has no way of knowing if we're in or out
785 // of this loop when he issues a "remote-signal".
786 snprintf(buffer, bufferSize,
787 "S%02x", type);
788 if (send(buffer) < 0)
789 return true;
790 continue;
791
792 case GDBRegR:
793 if (2 * regCache->size() > bufferSize)
794 panic("buffer too small");
795
796 mem2hex(buffer, regCache->data(), regCache->size());
797 if (send(buffer) < 0)
798 return true;
799 continue;
800
801 case GDBRegW:
802 p = hex2mem(regCache->data(), p, regCache->size());
803 if (p == NULL || *p != '\0') {
804 if (send("E01") < 0)
805 return true;
806 } else {
807 regCache->setRegs(context);
808 if (send("OK") < 0)
809 return true;
810 }
811 continue;
812
813 case GDBMemR:
814 val = hex2i(&p);
815 if (*p++ != ',') {
816 if (send("E02") < 0)
817 return true;
818 continue;
819 }
820 len = hex2i(&p);
821 if (*p != '\0') {
822 if (send("E03") < 0)
823 return true;
824 continue;
825 }
826 if (len > bufferSize) {
827 if (send("E04") < 0)
828 return true;
829 continue;
830 }
831 if (!acc(val, len)) {
832 if (send("E05") < 0)
833 return true;
834 continue;
835 }
836
837 if (read(val, (size_t)len, buffer)) {
838 // variable length array would be nice, but C++ doesn't
839 // officially support those...
840 char *temp = new char[2*len+1];
841 mem2hex(temp, buffer, len);
842 if (send(temp) < 0) {
843 delete [] temp;
844 return true;
845 }
846 delete [] temp;
847 } else {
848 if (send("E05") < 0)
849 return true;
850 }
851 continue;
852
853 case GDBMemW:
854 val = hex2i(&p);
855 if (*p++ != ',') {
856 if (send("E06") < 0)
857 return true;
858 continue;
859 }
860 len = hex2i(&p);
861 if (*p++ != ':') {
862 if (send("E07") < 0)
863 return true;
864 continue;
865 }
866 if (len > datalen - (p - data)) {
867 if (send("E08") < 0)
868 return true;
869 continue;
870 }
871 p = hex2mem(buffer, p, bufferSize);
872 if (p == NULL) {
873 if (send("E09") < 0)
874 return true;
875 continue;
876 }
877 if (!acc(val, len)) {
878 if (send("E0A") < 0)
879 return true;
880 continue;
881 }
882 if (write(val, (size_t)len, buffer)) {
883 if (send("OK") < 0)
884 return true;
885 } else {
886 if (send("E0B") < 0)
887 return true;
888 }
889 continue;
890
891 case GDBSetThread:
892 subcmd = *p++;
893 val = hex2i(&p);
894 if (val == 0) {
895 if (send("OK") < 0)
896 return true;
897 } else {
898 if (send("E01") < 0)
899 return true;
900 }
901 continue;
902
903 case GDBDetach:
904 case GDBKill:
905 active = false;
906 clearSingleStep();
907 detach();
908 return true;
909
910 case GDBAsyncCont:
911 subcmd = hex2i(&p);
912 if (*p++ == ';') {
913 val = hex2i(&p);
914 context->pcState(val);
915 }
916 clearSingleStep();
917 return true;
918
919 case GDBCont:
920 if (p - data < (ptrdiff_t)datalen) {
921 val = hex2i(&p);
922 context->pcState(val);
923 }
924 clearSingleStep();
925 return true;
926
927 case GDBAsyncStep:
928 subcmd = hex2i(&p);
929 if (*p++ == ';') {
930 val = hex2i(&p);
931 context->pcState(val);
932 }
933 setSingleStep();
934 return true;
935
936 case GDBStep:
937 if (p - data < (ptrdiff_t)datalen) {
938 val = hex2i(&p);
939 context->pcState(val);
940 }
941 setSingleStep();
942 return true;
943
944 case GDBClrHwBkpt:
945 subcmd = *p++;
946 if (*p++ != ',' && send("E0D") < 0)
947 return true;
948 val = hex2i(&p);
949 if (*p++ != ',' && send("E0D") < 0)
950 return true;
951 len = hex2i(&p);
952
953 DPRINTF(GDBMisc, "clear %s, addr=%#x, len=%d\n",
954 break_type(subcmd), val, len);
955
956 ret = false;
957
958 switch (subcmd) {
959 case '0': // software breakpoint
960 ret = removeSoftBreak(val, len);
961 break;
962
963 case '1': // hardware breakpoint
964 ret = removeHardBreak(val, len);
965 break;
966
967 case '2': // write watchpoint
968 case '3': // read watchpoint
969 case '4': // access watchpoint
970 default: // unknown
971 if (send("") < 0)
972 return true;
973 break;
974 }
975
976 if (send(ret ? "OK" : "E0C") < 0)
977 return true;
978 continue;
979
980 case GDBSetHwBkpt:
981 subcmd = *p++;
982 if (*p++ != ',' && send("E0D") < 0)
983 return true;
984 val = hex2i(&p);
985 if (*p++ != ',' && send("E0D") < 0)
986 return true;
987 len = hex2i(&p);
988
989 DPRINTF(GDBMisc, "set %s, addr=%#x, len=%d\n",
990 break_type(subcmd), val, len);
991
992 ret = false;
993
994 switch (subcmd) {
995 case '0': // software breakpoint
996 ret = insertSoftBreak(val, len);
997 break;
998
999 case '1': // hardware breakpoint
1000 ret = insertHardBreak(val, len);
1001 break;
1002
1003 case '2': // write watchpoint
1004 case '3': // read watchpoint
1005 case '4': // access watchpoint
1006 default: // unknown
1007 if (send("") < 0)
1008 return true;
1009 break;
1010 }
1011
1012 if (send(ret ? "OK" : "E0C") < 0)
1013 return true;
1014 continue;
1015
1016 case GDBQueryVar:
1017 var = string(p, datalen - 1);
1018 if (var == "C") {
1019 if (send("QC0") < 0)
1020 return true;
1021 } else {
1022 if (send("") < 0)
1023 return true;
1024 }
1025 continue;
1026
1027 case GDBSetBaud:
1028 case GDBSetBreak:
1029 case GDBDebug:
1030 case GDBCycleStep:
1031 case GDBSigCycleStep:
1032 case GDBReadReg:
1033 case GDBSetVar:
1034 case GDBReset:
1035 case GDBThreadAlive:
1036 case GDBTargetExit:
1037 case GDBBinaryDload:
1038 // Unsupported command
1039 DPRINTF(GDBMisc, "Unsupported command: %s\n",
1040 gdb_command(command));
1041 DDUMP(GDBMisc, (uint8_t *)data, datalen);
1042 if (send("") < 0)
1043 return true;
1044 continue;
1045
1046 default:
1047 // Unknown command.
1048 DPRINTF(GDBMisc, "Unknown command: %c(%#x)\n",
1049 command, command);
1050 if (send("") < 0)
1051 return true;
1052 continue;
1053
1054
1055 }
1056 }
1057
1058 return true;
1059}
1060
1061// Convert a hex digit into an integer.
1062// This returns -1 if the argument passed is no valid hex digit.
1063int
1064BaseRemoteGDB::digit2i(char c)
1065{
1066 if (c >= '0' && c <= '9')
1067 return (c - '0');
1068 else if (c >= 'a' && c <= 'f')
1069 return (c - 'a' + 10);
1070 else if (c >= 'A' && c <= 'F')
1071
1072 return (c - 'A' + 10);
1073 else
1074 return (-1);
1075}
1076
1077// Convert the low 4 bits of an integer into an hex digit.
1078char
1079BaseRemoteGDB::i2digit(int n)
1080{
1081 return ("0123456789abcdef"[n & 0x0f]);
1082}
1083
1084// Convert a byte array into an hex string.
1085void
1086BaseRemoteGDB::mem2hex(char *vdst, const char *vsrc, int len)
1087{
1088 char *dst = vdst;
1089 const char *src = vsrc;
1090
1091 while (len--) {
1092 *dst++ = i2digit(*src >> 4);
1093 *dst++ = i2digit(*src++);
1094 }
1095 *dst = '\0';
1096}
1097
1098// Convert an hex string into a byte array.
1099// This returns a pointer to the character following the last valid
1100// hex digit. If the string ends in the middle of a byte, NULL is
1101// returned.
1102const char *
1103BaseRemoteGDB::hex2mem(char *vdst, const char *src, int maxlen)
1104{
1105 char *dst = vdst;
1106 int msb, lsb;
1107
1108 while (*src && maxlen--) {
1109 msb = digit2i(*src++);
1110 if (msb < 0)
1111 return (src - 1);
1112 lsb = digit2i(*src++);
1113 if (lsb < 0)
1114 return (NULL);
1115 *dst++ = (msb << 4) | lsb;
1116 }
1117 return (src);
1118}
1119
1120// Convert an hex string into an integer.
1121// This returns a pointer to the character following the last valid
1122// hex digit.
1123Addr
1124BaseRemoteGDB::hex2i(const char **srcp)
1125{
1126 const char *src = *srcp;
1127 Addr r = 0;
1128 int nibble;
1129
1130 while ((nibble = digit2i(*src)) >= 0) {
1131 r *= 16;
1132 r += nibble;
1133 src++;
1134 }
1135 *srcp = src;
1136 return (r);
1137}
1138