1/*
2 * Copyright (c) 2002-2005 The Regents of The University of Michigan
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are
7 * met: redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer;
9 * redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution;
12 * neither the name of the copyright holders nor the names of its
13 * contributors may be used to endorse or promote products derived from
14 * this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 * Authors: Nathan Binkert
29 */
30
31/*
32 * Copyright (c) 1990, 1993
33 * The Regents of the University of California. All rights reserved.
34 *
35 * This software was developed by the Computer Systems Engineering group
36 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
37 * contributed to Berkeley.
38 *
39 * All advertising materials mentioning features or use of this software
40 * must display the following acknowledgement:
41 * This product includes software developed by the University of
42 * California, Lawrence Berkeley Laboratories.
43 *
44 * Redistribution and use in source and binary forms, with or without
45 * modification, are permitted provided that the following conditions
46 * are met:
47 * 1. Redistributions of source code must retain the above copyright
48 * notice, this list of conditions and the following disclaimer.
49 * 2. Redistributions in binary form must reproduce the above copyright
50 * notice, this list of conditions and the following disclaimer in the
51 * documentation and/or other materials provided with the distribution.
52 * 3. All advertising materials mentioning features or use of this software
53 * must display the following acknowledgement:
54 * This product includes software developed by the University of
55 * California, Berkeley and its contributors.
56 * 4. Neither the name of the University nor the names of its contributors
57 * may be used to endorse or promote products derived from this software
58 * without specific prior written permission.
59 *
60 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
61 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
62 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
63 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
64 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
65 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
66 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
67 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
68 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
69 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
70 * SUCH DAMAGE.
71 *
72 * @(#)kgdb_stub.c 8.4 (Berkeley) 1/12/94
73 */
74
75/*-
76 * Copyright (c) 2001 The NetBSD Foundation, Inc.
77 * All rights reserved.
78 *
79 * This code is derived from software contributed to The NetBSD Foundation
80 * by Jason R. Thorpe.
81 *
82 * Redistribution and use in source and binary forms, with or without
83 * modification, are permitted provided that the following conditions
84 * are met:
85 * 1. Redistributions of source code must retain the above copyright
86 * notice, this list of conditions and the following disclaimer.
87 * 2. Redistributions in binary form must reproduce the above copyright
88 * notice, this list of conditions and the following disclaimer in the
89 * documentation and/or other materials provided with the distribution.
90 * 3. All advertising materials mentioning features or use of this software
91 * must display the following acknowledgement:
92 * This product includes software developed by the NetBSD
93 * Foundation, Inc. and its contributors.
94 * 4. Neither the name of The NetBSD Foundation nor the names of its
95 * contributors may be used to endorse or promote products derived
96 * from this software without specific prior written permission.
97 *
98 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
99 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
100 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
101 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
102 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
103 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
104 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
105 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
106 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
107 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
108 * POSSIBILITY OF SUCH DAMAGE.
109 */
110
111/*
112 * $NetBSD: kgdb_stub.c,v 1.8 2001/07/07 22:58:00 wdk Exp $
113 *
114 * Taken from NetBSD
115 *
116 * "Stub" to allow remote cpu to debug over a serial line using gdb.
117 */
118
119#include <sys/signal.h>
120
121#include <string>
122#include <unistd.h>
123
124#include "arch/vtophys.hh"
125#include "base/intmath.hh"
126#include "base/kgdb.h"
127#include "base/remote_gdb.hh"
128#include "base/socket.hh"
129#include "base/trace.hh"
130#include "config/full_system.hh"
131#include "cpu/thread_context.hh"
132#include "cpu/static_inst.hh"
133#include "mem/physical.hh"
134#include "mem/port.hh"
135#include "sim/system.hh"
136
137using namespace std;
138using namespace TheISA;
139
140#ifndef NDEBUG
141vector debuggers;
142int current_debugger = -1;
143
144void
145debugger()
146{
147 if (current_debugger >= 0 && current_debugger < debuggers.size()) {
148 RemoteGDB *gdb = debuggers[current_debugger];
149 if (!gdb->isattached())
150 gdb->listener->accept();
151 if (gdb->isattached())
152 gdb->trap(ALPHA_KENTRY_IF);
153 }
154}
155#endif
156
157///////////////////////////////////////////////////////////
158//
159//
160//
161
162GDBListener::Event::Event(GDBListener *l, int fd, int e)
163 : PollEvent(fd, e), listener(l)
164{}
165
166void
167GDBListener::Event::process(int revent)
168{
169 listener->accept();
170}
171
172GDBListener::GDBListener(RemoteGDB *g, int p)
173 : event(NULL), gdb(g), port(p)
174{
175 assert(!gdb->listener);
176 gdb->listener = this;
177}
178
179GDBListener::~GDBListener()
180{
181 if (event)
182 delete event;
183}
184
185string
186GDBListener::name()
187{
188 return gdb->name() + ".listener";
189}
190
191void
192GDBListener::listen()
193{
194 while (!listener.listen(port, true)) {
195 DPRINTF(GDBMisc, "Can't bind port %d\n", port);
196 port++;
197 }
198
199 event = new Event(this, listener.getfd(), POLLIN);
200 pollQueue.schedule(event);
201
202#ifndef NDEBUG
203 gdb->number = debuggers.size();
204 debuggers.push_back(gdb);
205#endif
206
207#ifndef NDEBUG
208 ccprintf(cerr, "%d: %s: listening for remote gdb #%d on port %d\n",
209 curTick, name(), gdb->number, port);
210#else
211 ccprintf(cerr, "%d: %s: listening for remote gdb on port %d\n",
212 curTick, name(), port);
213#endif
214}
215
216void
217GDBListener::accept()
218{
219 if (!listener.islistening())
220 panic("GDBListener::accept(): cannot accept if we're not listening!");
221
222 int sfd = listener.accept(true);
223
224 if (sfd != -1) {
225 if (gdb->isattached())
226 close(sfd);
227 else
228 gdb->attach(sfd);
229 }
230}
231
232///////////////////////////////////////////////////////////
233//
234//
235//
236int digit2i(char);
237char i2digit(int);
238void mem2hex(void *, const void *, int);
239const char *hex2mem(void *, const char *, int);
240Addr hex2i(const char **);
241
242RemoteGDB::Event::Event(RemoteGDB *g, int fd, int e)
243 : PollEvent(fd, e), gdb(g)
244{}
245
246void
247RemoteGDB::Event::process(int revent)
248{
249 if (revent & POLLIN)
250 gdb->trap(ALPHA_KENTRY_IF);
251 else if (revent & POLLNVAL)
252 gdb->detach();
253}
254
255RemoteGDB::RemoteGDB(System *_system, ThreadContext *c)
256 : event(NULL), listener(NULL), number(-1), fd(-1),
257 active(false), attached(false),
258 system(_system), pmem(_system->physmem), context(c)
259{
260 memset(gdbregs, 0, sizeof(gdbregs));
261}
262
263RemoteGDB::~RemoteGDB()
264{
265 if (event)
266 delete event;
267}
268
269string
270RemoteGDB::name()
271{
272 return system->name() + ".remote_gdb";
273}
274
275bool
276RemoteGDB::isattached()
277{ return attached; }
278
279void
280RemoteGDB::attach(int f)
281{
282 fd = f;
283
284 event = new Event(this, fd, POLLIN);
285 pollQueue.schedule(event);
286
287 attached = true;
288 DPRINTFN("remote gdb attached\n");
289}
290
291void
292RemoteGDB::detach()
293{
294 attached = false;
295 close(fd);
296 fd = -1;
297
298 pollQueue.remove(event);
299 DPRINTFN("remote gdb detached\n");
300}
301
302const char *
303gdb_command(char cmd)
304{
305 switch (cmd) {
306 case KGDB_SIGNAL: return "KGDB_SIGNAL";
307 case KGDB_SET_BAUD: return "KGDB_SET_BAUD";
308 case KGDB_SET_BREAK: return "KGDB_SET_BREAK";
309 case KGDB_CONT: return "KGDB_CONT";
310 case KGDB_ASYNC_CONT: return "KGDB_ASYNC_CONT";
311 case KGDB_DEBUG: return "KGDB_DEBUG";
312 case KGDB_DETACH: return "KGDB_DETACH";
313 case KGDB_REG_R: return "KGDB_REG_R";
314 case KGDB_REG_W: return "KGDB_REG_W";
315 case KGDB_SET_THREAD: return "KGDB_SET_THREAD";
316 case KGDB_CYCLE_STEP: return "KGDB_CYCLE_STEP";
317 case KGDB_SIG_CYCLE_STEP: return "KGDB_SIG_CYCLE_STEP";
318 case KGDB_KILL: return "KGDB_KILL";
319 case KGDB_MEM_W: return "KGDB_MEM_W";
320 case KGDB_MEM_R: return "KGDB_MEM_R";
321 case KGDB_SET_REG: return "KGDB_SET_REG";
322 case KGDB_READ_REG: return "KGDB_READ_REG";
323 case KGDB_QUERY_VAR: return "KGDB_QUERY_VAR";
324 case KGDB_SET_VAR: return "KGDB_SET_VAR";
325 case KGDB_RESET: return "KGDB_RESET";
326 case KGDB_STEP: return "KGDB_STEP";
327 case KGDB_ASYNC_STEP: return "KGDB_ASYNC_STEP";
328 case KGDB_THREAD_ALIVE: return "KGDB_THREAD_ALIVE";
329 case KGDB_TARGET_EXIT: return "KGDB_TARGET_EXIT";
330 case KGDB_BINARY_DLOAD: return "KGDB_BINARY_DLOAD";
331 case KGDB_CLR_HW_BKPT: return "KGDB_CLR_HW_BKPT";
332 case KGDB_SET_HW_BKPT: return "KGDB_SET_HW_BKPT";
333 case KGDB_START: return "KGDB_START";
334 case KGDB_END: return "KGDB_END";
335 case KGDB_GOODP: return "KGDB_GOODP";
336 case KGDB_BADP: return "KGDB_BADP";
337 default: return "KGDB_UNKNOWN";
338 }
339}
340
341///////////////////////////////////////////////////////////
342// RemoteGDB::acc
343//
344// Determine if the mapping at va..(va+len) is valid.
345//
346bool
347RemoteGDB::acc(Addr va, size_t len)
348{
349 Addr last_va;
350
351 va = TheISA::TruncPage(va);
352 last_va = TheISA::RoundPage(va + len);
353
354 do {
355 if (TheISA::IsK0Seg(va)) {
356 if (va < (TheISA::K0SegBase + pmem->size())) {
357 DPRINTF(GDBAcc, "acc: Mapping is valid K0SEG <= "
358 "%#x < K0SEG + size\n", va);
359 return true;
360 } else {
361 DPRINTF(GDBAcc, "acc: Mapping invalid %#x > K0SEG + size\n",
362 va);
363 return false;
364 }
365 }
366
367 /**
368 * This code says that all accesses to palcode (instruction and data)
369 * are valid since there isn't a va->pa mapping because palcode is
370 * accessed physically. At some point this should probably be cleaned up
371 * but there is no easy way to do it.
372 */
373
374 if (AlphaISA::PcPAL(va) || va < 0x10000)
375 return true;
376
377 Addr ptbr = context->readMiscReg(AlphaISA::IPR_PALtemp20);
378 TheISA::PageTableEntry pte = TheISA::kernel_pte_lookup(context->getPhysPort(), ptbr, va);
379 if (!pte.valid()) {
380 DPRINTF(GDBAcc, "acc: %#x pte is invalid\n", va);
381 return false;
382 }
383 va += TheISA::PageBytes;
384 } while (va < last_va);
385
386 DPRINTF(GDBAcc, "acc: %#x mapping is valid\n", va);
387 return true;
388}
389
390///////////////////////////////////////////////////////////
391// RemoteGDB::signal
392//
393// Translate a trap number into a Unix-compatible signal number.
394// (GDB only understands Unix signal numbers.)
395//
396int
397RemoteGDB::signal(int type)
398{
399 switch (type) {
400 case ALPHA_KENTRY_INT:
401 return (SIGTRAP);
402
403 case ALPHA_KENTRY_UNA:
404 return (SIGBUS);
405
406 case ALPHA_KENTRY_ARITH:
407 return (SIGFPE);
408
409 case ALPHA_KENTRY_IF:
410 return (SIGILL);
411
412 case ALPHA_KENTRY_MM:
413 return (SIGSEGV);
414
415 default:
416 panic("unknown signal type");
417 return 0;
418 }
419}
420
421///////////////////////////////////////////////////////////
422// RemoteGDB::getregs
423//
424// Translate the kernel debugger register format into
425// the GDB register format.
426void
427RemoteGDB::getregs()
428{
429 memset(gdbregs, 0, sizeof(gdbregs));
430
431 gdbregs[KGDB_REG_PC] = context->readPC();
432
433 // @todo: Currently this is very Alpha specific.
434 if (AlphaISA::PcPAL(gdbregs[KGDB_REG_PC])) {
435 for (int i = 0; i < TheISA::NumIntArchRegs; ++i) {
436 gdbregs[i] = context->readIntReg(AlphaISA::reg_redir[i]);
437 }
438 } else {
439 for (int i = 0; i < TheISA::NumIntArchRegs; ++i) {
440 gdbregs[i] = context->readIntReg(i);
441 }
442 }
443
444#ifdef KGDB_FP_REGS
445 for (int i = 0; i < TheISA::NumFloatArchRegs; ++i) {
446 gdbregs[i + KGDB_REG_F0] = context->readFloatRegBits(i);
447 }
448#endif
449}
450
451///////////////////////////////////////////////////////////
452// RemoteGDB::setregs
453//
454// Translate the GDB register format into the kernel
455// debugger register format.
456//
457void
458RemoteGDB::setregs()
459{
460 // @todo: Currently this is very Alpha specific.
461 if (AlphaISA::PcPAL(gdbregs[KGDB_REG_PC])) {
462 for (int i = 0; i < TheISA::NumIntArchRegs; ++i) {
463 context->setIntReg(AlphaISA::reg_redir[i], gdbregs[i]);
464 }
465 } else {
466 for (int i = 0; i < TheISA::NumIntArchRegs; ++i) {
467 context->setIntReg(i, gdbregs[i]);
468 }
469 }
470
471#ifdef KGDB_FP_REGS
472 for (int i = 0; i < TheISA::NumFloatArchRegs; ++i) {
473 context->setFloatRegBits(i, gdbregs[i + KGDB_REG_F0]);
474 }
475#endif
476 context->setPC(gdbregs[KGDB_REG_PC]);
477}
478
479void
480RemoteGDB::setTempBreakpoint(TempBreakpoint &bkpt, Addr addr)
481{
482 DPRINTF(GDBMisc, "setTempBreakpoint: addr=%#x\n", addr);
483
484 bkpt.address = addr;
485 insertHardBreak(addr, 4);
486}
487
488void
489RemoteGDB::clearTempBreakpoint(TempBreakpoint &bkpt)
490{
491 DPRINTF(GDBMisc, "setTempBreakpoint: addr=%#x\n",
492 bkpt.address);
493
494
495 removeHardBreak(bkpt.address, 4);
496 bkpt.address = 0;
497}
498
499void
500RemoteGDB::clearSingleStep()
501{
502 DPRINTF(GDBMisc, "clearSingleStep bt_addr=%#x nt_addr=%#x\n",
503 takenBkpt.address, notTakenBkpt.address);
504
505 if (takenBkpt.address != 0)
506 clearTempBreakpoint(takenBkpt);
507
508 if (notTakenBkpt.address != 0)
509 clearTempBreakpoint(notTakenBkpt);
510}
511
512void
513RemoteGDB::setSingleStep()
514{
515 Addr pc = context->readPC();
516 Addr npc, bpc;
517 bool set_bt = false;
518
519 npc = pc + sizeof(MachInst);
520
521 // User was stopped at pc, e.g. the instruction at pc was not
522 // executed.
523 MachInst inst = read<MachInst>(pc);
524 StaticInstPtr si(inst);
525 if (si->hasBranchTarget(pc, context, bpc)) {
526 // Don't bother setting a breakpoint on the taken branch if it
527 // is the same as the next pc
528 if (bpc != npc)
529 set_bt = true;
530 }
531
532 DPRINTF(GDBMisc, "setSingleStep bt_addr=%#x nt_addr=%#x\n",
533 takenBkpt.address, notTakenBkpt.address);
534
535 setTempBreakpoint(notTakenBkpt, npc);
536
537 if (set_bt)
538 setTempBreakpoint(takenBkpt, bpc);
539}
540
541/////////////////////////
542//
543//
544
545uint8_t
546RemoteGDB::getbyte()
547{
548 uint8_t b;
549 ::read(fd, &b, 1);
550 return b;
551}
552
553void
554RemoteGDB::putbyte(uint8_t b)
555{
556 ::write(fd, &b, 1);
557}
558
559// Send a packet to gdb
560void
561RemoteGDB::send(const char *bp)
562{
563 const char *p;
564 uint8_t csum, c;
565
566 DPRINTF(GDBSend, "send: %s\n", bp);
567
568 do {
569 p = bp;
570 putbyte(KGDB_START);
571 for (csum = 0; (c = *p); p++) {
572 putbyte(c);
573 csum += c;
574 }
575 putbyte(KGDB_END);
576 putbyte(i2digit(csum >> 4));
577 putbyte(i2digit(csum));
578 } while ((c = getbyte() & 0x7f) == KGDB_BADP);
579}
580
581// Receive a packet from gdb
582int
583RemoteGDB::recv(char *bp, int maxlen)
584{
585 char *p;
586 int c, csum;
587 int len;
588
589 do {
590 p = bp;
591 csum = len = 0;
592 while ((c = getbyte()) != KGDB_START)
593 ;
594
595 while ((c = getbyte()) != KGDB_END && len < maxlen) {
596 c &= 0x7f;
597 csum += c;
598 *p++ = c;
599 len++;
600 }
601 csum &= 0xff;
602 *p = '\0';
603
604 if (len >= maxlen) {
605 putbyte(KGDB_BADP);
606 continue;
607 }
608
609 csum -= digit2i(getbyte()) * 16;
610 csum -= digit2i(getbyte());
611
612 if (csum == 0) {
613 putbyte(KGDB_GOODP);
614 // Sequence present?
615 if (bp[2] == ':') {
616 putbyte(bp[0]);
617 putbyte(bp[1]);
618 len -= 3;
619 bcopy(bp + 3, bp, len);
620 }
621 break;
622 }
623 putbyte(KGDB_BADP);
624 } while (1);
625
626 DPRINTF(GDBRecv, "recv: %s: %s\n", gdb_command(*bp), bp);
627
628 return (len);
629}
630
631// Read bytes from kernel address space for debugger.
632bool
633RemoteGDB::read(Addr vaddr, size_t size, char *data)
634{
635 static Addr lastaddr = 0;
636 static size_t lastsize = 0;
637
638 if (vaddr < 10) {
639 DPRINTF(GDBRead, "read: reading memory location zero!\n");
640 vaddr = lastaddr + lastsize;
641 }
642
643 DPRINTF(GDBRead, "read: addr=%#x, size=%d", vaddr, size);
644
645 VirtualPort *vp = context->getVirtPort(context);
646 vp->readBlob(vaddr, (uint8_t*)data, size);
647 context->delVirtPort(vp);
648
649#if TRACING_ON
650 if (DTRACE(GDBRead)) {
651 if (DTRACE(GDBExtra)) {
652 char buf[1024];
653 mem2hex(buf, data, size);
654 DPRINTFNR(": %s\n", buf);
655 } else
656 DPRINTFNR("\n");
657 }
658#endif
659
660 return true;
661}
662
663// Write bytes to kernel address space for debugger.
664bool
665RemoteGDB::write(Addr vaddr, size_t size, const char *data)
666{
667 static Addr lastaddr = 0;
668 static size_t lastsize = 0;
669
670 if (vaddr < 10) {
671 DPRINTF(GDBWrite, "write: writing memory location zero!\n");
672 vaddr = lastaddr + lastsize;
673 }
674
675 if (DTRACE(GDBWrite)) {
676 DPRINTFN("write: addr=%#x, size=%d", vaddr, size);
677 if (DTRACE(GDBExtra)) {
678 char buf[1024];
679 mem2hex(buf, data, size);
680 DPRINTFNR(": %s\n", buf);
681 } else
682 DPRINTFNR("\n");
683 }
684 VirtualPort *vp = context->getVirtPort(context);
685 vp->writeBlob(vaddr, (uint8_t*)data, size);
686 context->delVirtPort(vp);
687
688#ifdef IMB
689 alpha_pal_imb();
690#endif
691
692 return true;
693}
694
695
696PCEventQueue *RemoteGDB::getPcEventQueue()
697{
698 return &system->pcEventQueue;
699}
700
701
702RemoteGDB::HardBreakpoint::HardBreakpoint(RemoteGDB *_gdb, Addr pc)
703 : PCEvent(_gdb->getPcEventQueue(), "HardBreakpoint Event", pc),
704 gdb(_gdb), refcount(0)
705{
706 DPRINTF(GDBMisc, "creating hardware breakpoint at %#x\n", evpc);
707}
708
709void
710RemoteGDB::HardBreakpoint::process(ThreadContext *tc)
711{
712 DPRINTF(GDBMisc, "handling hardware breakpoint at %#x\n", pc());
713
714 if (tc == gdb->context)
715 gdb->trap(ALPHA_KENTRY_INT);
716}
717
718bool
719RemoteGDB::insertSoftBreak(Addr addr, size_t len)
720{
721 if (len != sizeof(MachInst))
722 panic("invalid length\n");
723
724 return insertHardBreak(addr, len);
725}
726
727bool
728RemoteGDB::removeSoftBreak(Addr addr, size_t len)
729{
730 if (len != sizeof(MachInst))
731 panic("invalid length\n");
732
733 return removeHardBreak(addr, len);
734}
735
736bool
737RemoteGDB::insertHardBreak(Addr addr, size_t len)
738{
739 if (len != sizeof(MachInst))
740 panic("invalid length\n");
741
742 DPRINTF(GDBMisc, "inserting hardware breakpoint at %#x\n", addr);
743
744 HardBreakpoint *&bkpt = hardBreakMap[addr];
745 if (bkpt == 0)
746 bkpt = new HardBreakpoint(this, addr);
747
748 bkpt->refcount++;
749
750 return true;
751}
752
753bool
754RemoteGDB::removeHardBreak(Addr addr, size_t len)
755{
756 if (len != sizeof(MachInst))
757 panic("invalid length\n");
758
759 DPRINTF(GDBMisc, "removing hardware breakpoint at %#x\n", addr);
760
761 break_iter_t i = hardBreakMap.find(addr);
762 if (i == hardBreakMap.end())
763 return false;
764
765 HardBreakpoint *hbp = (*i).second;
766 if (--hbp->refcount == 0) {
767 delete hbp;
768 hardBreakMap.erase(i);
769 }
770
771 return true;
772}
773
774const char *
775break_type(char c)
776{
777 switch(c) {
778 case '0': return "software breakpoint";
779 case '1': return "hardware breakpoint";
780 case '2': return "write watchpoint";
781 case '3': return "read watchpoint";
782 case '4': return "access watchpoint";
783 default: return "unknown breakpoint/watchpoint";
784 }
785}
786
787// This function does all command processing for interfacing to a
788// remote gdb. Note that the error codes are ignored by gdb at
789// present, but might eventually become meaningful. (XXX) It might
790// makes sense to use POSIX errno values, because that is what the
791// gdb/remote.c functions want to return.
792bool
793RemoteGDB::trap(int type)
794{
795 uint64_t val;
796 size_t datalen, len;
797 char data[KGDB_BUFLEN + 1];
798 char buffer[sizeof(gdbregs) * 2 + 256];
799 const char *p;
800 char command, subcmd;
801 string var;
802 bool ret;
803
804 if (!attached)
805 return false;
806
807 DPRINTF(GDBMisc, "trap: PC=%#x NPC=%#x\n",
808 context->readPC(), context->readNextPC());
809
810 clearSingleStep();
811
812 /*
813 * The first entry to this function is normally through
814 * a breakpoint trap in kgdb_connect(), in which case we
815 * must advance past the breakpoint because gdb will not.
816 *
817 * On the first entry here, we expect that gdb is not yet
818 * listening to us, so just enter the interaction loop.
819 * After the debugger is "active" (connected) it will be
820 * waiting for a "signaled" message from us.
821 */
822 if (!active)
823 active = true;
824 else
825 // Tell remote host that an exception has occurred.
826 snprintf((char *)buffer, sizeof(buffer), "S%02x", signal(type));
827 send(buffer);
828
829 // Stick frame regs into our reg cache.
830 getregs();
831
832 for (;;) {
833 datalen = recv(data, sizeof(data));
834 data[sizeof(data) - 1] = 0; // Sentinel
835 command = data[0];
836 subcmd = 0;
837 p = data + 1;
838 switch (command) {
839
840 case KGDB_SIGNAL:
841 // if this command came from a running gdb, answer it --
842 // the other guy has no way of knowing if we're in or out
843 // of this loop when he issues a "remote-signal".
844 snprintf((char *)buffer, sizeof(buffer), "S%02x", signal(type));
845 send(buffer);
846 continue;
847
848 case KGDB_REG_R:
849 if (2 * sizeof(gdbregs) > sizeof(buffer))
850 panic("buffer too small");
851
852 mem2hex(buffer, gdbregs, sizeof(gdbregs));
853 send(buffer);
854 continue;
855
856 case KGDB_REG_W:
857 p = hex2mem(gdbregs, p, sizeof(gdbregs));
858 if (p == NULL || *p != '\0')
859 send("E01");
860 else {
861 setregs();
862 send("OK");
863 }
864 continue;
865
866#if 0
867 case KGDB_SET_REG:
868 val = hex2i(&p);
869 if (*p++ != '=') {
870 send("E01");
871 continue;
872 }
873 if (val < 0 && val >= KGDB_NUMREGS) {
874 send("E01");
875 continue;
876 }
877
878 gdbregs[val] = hex2i(&p);
879 setregs();
880 send("OK");
881
882 continue;
883#endif
884
885 case KGDB_MEM_R:
886 val = hex2i(&p);
887 if (*p++ != ',') {
888 send("E02");
889 continue;
890 }
891 len = hex2i(&p);
892 if (*p != '\0') {
893 send("E03");
894 continue;
895 }
896 if (len > sizeof(buffer)) {
897 send("E04");
898 continue;
899 }
900 if (!acc(val, len)) {
901 send("E05");
902 continue;
903 }
904
905 if (read(val, (size_t)len, (char *)buffer)) {
906 // variable length array would be nice, but C++ doesn't
907 // officially support those...
908 char *temp = new char[2*len+1];
909 mem2hex(temp, buffer, len);
910 send(temp);
911 delete [] temp;
912 } else {
913 send("E05");
914 }
915 continue;
916
917 case KGDB_MEM_W:
918 val = hex2i(&p);
919 if (*p++ != ',') {
920 send("E06");
921 continue;
922 }
923 len = hex2i(&p);
924 if (*p++ != ':') {
925 send("E07");
926 continue;
927 }
928 if (len > datalen - (p - data)) {
929 send("E08");
930 continue;
931 }
932 p = hex2mem(buffer, p, sizeof(buffer));
933 if (p == NULL) {
934 send("E09");
935 continue;
936 }
937 if (!acc(val, len)) {
938 send("E0A");
939 continue;
940 }
941 if (write(val, (size_t)len, (char *)buffer))
942 send("OK");
943 else
944 send("E0B");
945 continue;
946
947 case KGDB_SET_THREAD:
948 subcmd = *p++;
949 val = hex2i(&p);
950 if (val == 0)
951 send("OK");
952 else
953 send("E01");
954 continue;
955
956 case KGDB_DETACH:
957 case KGDB_KILL:
958 active = false;
959 clearSingleStep();
960 detach();
961 goto out;
962
963 case KGDB_ASYNC_CONT:
964 subcmd = hex2i(&p);
965 if (*p++ == ';') {
966 val = hex2i(&p);
967 context->setPC(val);
968 context->setNextPC(val + sizeof(MachInst));
969 }
970 clearSingleStep();
971 goto out;
972
973 case KGDB_CONT:
974 if (p - data < datalen) {
975 val = hex2i(&p);
976 context->setPC(val);
977 context->setNextPC(val + sizeof(MachInst));
978 }
979 clearSingleStep();
980 goto out;
981
982 case KGDB_ASYNC_STEP:
983 subcmd = hex2i(&p);
984 if (*p++ == ';') {
985 val = hex2i(&p);
986 context->setPC(val);
987 context->setNextPC(val + sizeof(MachInst));
988 }
989 setSingleStep();
990 goto out;
991
992 case KGDB_STEP:
993 if (p - data < datalen) {
994 val = hex2i(&p);
995 context->setPC(val);
996 context->setNextPC(val + sizeof(MachInst));
997 }
998 setSingleStep();
999 goto out;
1000
1001 case KGDB_CLR_HW_BKPT:
1002 subcmd = *p++;
1003 if (*p++ != ',') send("E0D");
1004 val = hex2i(&p);
1005 if (*p++ != ',') send("E0D");
1006 len = hex2i(&p);
1007
1008 DPRINTF(GDBMisc, "clear %s, addr=%#x, len=%d\n",
1009 break_type(subcmd), val, len);
1010
1011 ret = false;
1012
1013 switch (subcmd) {
1014 case '0': // software breakpoint
1015 ret = removeSoftBreak(val, len);
1016 break;
1017
1018 case '1': // hardware breakpoint
1019 ret = removeHardBreak(val, len);
1020 break;
1021
1022 case '2': // write watchpoint
1023 case '3': // read watchpoint
1024 case '4': // access watchpoint
1025 default: // unknown
1026 send("");
1027 break;
1028 }
1029
1030 send(ret ? "OK" : "E0C");
1031 continue;
1032
1033 case KGDB_SET_HW_BKPT:
1034 subcmd = *p++;
1035 if (*p++ != ',') send("E0D");
1036 val = hex2i(&p);
1037 if (*p++ != ',') send("E0D");
1038 len = hex2i(&p);
1039
1040 DPRINTF(GDBMisc, "set %s, addr=%#x, len=%d\n",
1041 break_type(subcmd), val, len);
1042
1043 ret = false;
1044
1045 switch (subcmd) {
1046 case '0': // software breakpoint
1047 ret = insertSoftBreak(val, len);
1048 break;
1049
1050 case '1': // hardware breakpoint
1051 ret = insertHardBreak(val, len);
1052 break;
1053
1054 case '2': // write watchpoint
1055 case '3': // read watchpoint
1056 case '4': // access watchpoint
1057 default: // unknown
1058 send("");
1059 break;
1060 }
1061
1062 send(ret ? "OK" : "E0C");
1063 continue;
1064
1065 case KGDB_QUERY_VAR:
1066 var = string(p, datalen - 1);
1067 if (var == "C")
1068 send("QC0");
1069 else
1070 send("");
1071 continue;
1072
1073 case KGDB_SET_BAUD:
1074 case KGDB_SET_BREAK:
1075 case KGDB_DEBUG:
1076 case KGDB_CYCLE_STEP:
1077 case KGDB_SIG_CYCLE_STEP:
1078 case KGDB_READ_REG:
1079 case KGDB_SET_VAR:
1080 case KGDB_RESET:
1081 case KGDB_THREAD_ALIVE:
1082 case KGDB_TARGET_EXIT:
1083 case KGDB_BINARY_DLOAD:
1084 // Unsupported command
1085 DPRINTF(GDBMisc, "Unsupported command: %s\n",
1086 gdb_command(command));
1087 DDUMP(GDBMisc, (uint8_t *)data, datalen);
1088 send("");
1089 continue;
1090
1091 default:
1092 // Unknown command.
1093 DPRINTF(GDBMisc, "Unknown command: %c(%#x)\n",
1094 command, command);
1095 send("");
1096 continue;
1097
1098
1099 }
1100 }
1101
1102 out:
1103 return true;
1104}
1105
1106// Convert a hex digit into an integer.
1107// This returns -1 if the argument passed is no valid hex digit.
1108int
1109digit2i(char c)
1110{
1111 if (c >= '0' && c <= '9')
1112 return (c - '0');
1113 else if (c >= 'a' && c <= 'f')
1114 return (c - 'a' + 10);
1115 else if (c >= 'A' && c <= 'F')
1116
1117 return (c - 'A' + 10);
1118 else
1119 return (-1);
1120}
1121
1122// Convert the low 4 bits of an integer into an hex digit.
1123char
1124i2digit(int n)
1125{
1126 return ("0123456789abcdef"[n & 0x0f]);
1127}
1128
1129// Convert a byte array into an hex string.
1130void
1131mem2hex(void *vdst, const void *vsrc, int len)
1132{
1133 char *dst = (char *)vdst;
1134 const char *src = (const char *)vsrc;
1135
1136 while (len--) {
1137 *dst++ = i2digit(*src >> 4);
1138 *dst++ = i2digit(*src++);
1139 }
1140 *dst = '\0';
1141}
1142
1143// Convert an hex string into a byte array.
1144// This returns a pointer to the character following the last valid
1145// hex digit. If the string ends in the middle of a byte, NULL is
1146// returned.
1147const char *
1148hex2mem(void *vdst, const char *src, int maxlen)
1149{
1150 char *dst = (char *)vdst;
1151 int msb, lsb;
1152
1153 while (*src && maxlen--) {
1154 msb = digit2i(*src++);
1155 if (msb < 0)
1156 return (src - 1);
1157 lsb = digit2i(*src++);
1158 if (lsb < 0)
1159 return (NULL);
1160 *dst++ = (msb << 4) | lsb;
1161 }
1162 return (src);
1163}
1164
1165// Convert an hex string into an integer.
1166// This returns a pointer to the character following the last valid
1167// hex digit.
1168Addr
1169hex2i(const char **srcp)
1170{
1171 const char *src = *srcp;
1172 Addr r = 0;
1173 int nibble;
1174
1175 while ((nibble = digit2i(*src)) >= 0) {
1176 r *= 16;
1177 r += nibble;
1178 src++;
1179 }
1180 *srcp = src;
1181 return (r);
1182}
1183