gem5/base/remote_gdb.cc
Kevin Lim e7825aab59 Changes to support automatic renaming of the shadow registers at decode time. This requires using an ExtMachInst (uint64_t) instead of the normal MachInst; the ExtMachInst is packed with extra decode context information. In the case of Alpha, the PAL mode is included.
The shadow registers are folded into the normal integer registers to ease renaming indexing.

Include the removed Opcdec class of instructions for faulting when a pal mode only instruction is decoded in non-pal mode.

arch/alpha/ev5.cc:
    Changes to automatically map the shadow registers if the instruction is in PAL mode.
arch/alpha/isa/branch.isa:
arch/alpha/isa/decoder.isa:
arch/alpha/isa/fp.isa:
arch/alpha/isa/int.isa:
arch/alpha/isa/mem.isa:
arch/alpha/isa/pal.isa:
arch/alpha/isa/unimp.isa:
    Changes for automatically using the shadow registers.  Now instructions must decode based on an ExtMachInst, which is a MachInst with any decode context information concatenated onto the higher order bits.
arch/alpha/isa/main.isa:
    Changes for automatically using the shadow registers.  Now instructions must decode based on an ExtMachInst, which is a MachInst with any decode context information concatenated onto the higher order bits.

    The decoder (for Alpha) uses the 32nd bit in order to determine if the machine is in PAL mode.  If it is, then it refers to the reg_redir table to determine the true index of the register it is using.

    Also include the opcdec instruction definition.
arch/alpha/isa_traits.hh:
    Define ExtMachInst type that is used by the static inst in order to decode the instruction, given the context of being in pal mode or not.

    Redefine the number of Int registers, splitting it into NumIntArchRegs (32) and NumIntRegs (32 + 8 shadow registers).

    Change the dependence tags to reflect the integer registers include the 8 shadow registers.

    Define function to make an ExtMachInst.  Currently it is somewhat specific to Alpha; in the future it must be decided to make this more generic and possibly slower, or leave it specific to each architecture and ifdef it within the CPU.
arch/isa_parser.py:
    Have static insts decode on the ExtMachInst.
base/remote_gdb.cc:
    Support the automatic remapping of shadow registers.  Remote GDB must now look at the PC being read in order to tell if it should use the normal register indices or the shadow register indices.
cpu/o3/regfile.hh:
    Comment out the pal registers; they are now a part of the integer registers.
cpu/simple/cpu.cc:
    Create an ExtMachInst to decode on, based on the normal MachInst and the PC of the instructoin.
cpu/static_inst.hh:
    Change from MachInst to ExtMachInst to support shadow register renaming.

--HG--
extra : convert_revision : 1d23eabf735e297068e1917445a6348e9f8c88d5
2006-03-03 15:28:25 -05:00

1232 lines
32 KiB
C++

/*
* Copyright (c) 2002-2005 The Regents of The University of Michigan
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met: redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer;
* redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution;
* neither the name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Copyright (c) 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* This software was developed by the Computer Systems Engineering group
* at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
* contributed to Berkeley.
*
* All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Lawrence Berkeley Laboratories.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)kgdb_stub.c 8.4 (Berkeley) 1/12/94
*/
/*-
* Copyright (c) 2001 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Jason R. Thorpe.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*
* $NetBSD: kgdb_stub.c,v 1.8 2001/07/07 22:58:00 wdk Exp $
*
* Taken from NetBSD
*
* "Stub" to allow remote cpu to debug over a serial line using gdb.
*/
#include <sys/signal.h>
#include <cstdio>
#include <string>
#include <unistd.h>
#include "base/intmath.hh"
#include "base/kgdb.h"
#include "base/remote_gdb.hh"
#include "base/socket.hh"
#include "base/trace.hh"
#include "cpu/exec_context.hh"
#include "cpu/static_inst.hh"
#include "mem/functional/physical.hh"
#include "sim/system.hh"
#include "arch/vtophys.hh"
using namespace std;
using namespace TheISA;
#ifndef NDEBUG
vector<RemoteGDB *> debuggers;
int current_debugger = -1;
void
debugger()
{
if (current_debugger >= 0 && current_debugger < debuggers.size()) {
RemoteGDB *gdb = debuggers[current_debugger];
if (!gdb->isattached())
gdb->listener->accept();
if (gdb->isattached())
gdb->trap(ALPHA_KENTRY_IF);
}
}
#endif
///////////////////////////////////////////////////////////
//
//
//
GDBListener::Event::Event(GDBListener *l, int fd, int e)
: PollEvent(fd, e), listener(l)
{}
void
GDBListener::Event::process(int revent)
{
listener->accept();
}
GDBListener::GDBListener(RemoteGDB *g, int p)
: event(NULL), gdb(g), port(p)
{
assert(!gdb->listener);
gdb->listener = this;
}
GDBListener::~GDBListener()
{
if (event)
delete event;
}
string
GDBListener::name()
{
return gdb->name() + ".listener";
}
void
GDBListener::listen()
{
while (!listener.listen(port, true)) {
DPRINTF(GDBMisc, "Can't bind port %d\n", port);
port++;
}
event = new Event(this, listener.getfd(), POLLIN);
pollQueue.schedule(event);
#ifndef NDEBUG
gdb->number = debuggers.size();
debuggers.push_back(gdb);
#endif
#ifndef NDEBUG
ccprintf(cerr, "%d: %s: listening for remote gdb #%d on port %d\n",
curTick, name(), gdb->number, port);
#else
ccprintf(cerr, "%d: %s: listening for remote gdb on port %d\n",
curTick, name(), port);
#endif
}
void
GDBListener::accept()
{
if (!listener.islistening())
panic("GDBListener::accept(): cannot accept if we're not listening!");
int sfd = listener.accept(true);
if (sfd != -1) {
if (gdb->isattached())
close(sfd);
else
gdb->attach(sfd);
}
}
///////////////////////////////////////////////////////////
//
//
//
int digit2i(char);
char i2digit(int);
void mem2hex(void *, const void *, int);
const char *hex2mem(void *, const char *, int);
Addr hex2i(const char **);
RemoteGDB::Event::Event(RemoteGDB *g, int fd, int e)
: PollEvent(fd, e), gdb(g)
{}
void
RemoteGDB::Event::process(int revent)
{
if (revent & POLLIN)
gdb->trap(ALPHA_KENTRY_IF);
else if (revent & POLLNVAL)
gdb->detach();
}
RemoteGDB::RemoteGDB(System *_system, ExecContext *c)
: event(NULL), listener(NULL), number(-1), fd(-1),
active(false), attached(false),
system(_system), pmem(_system->physmem), context(c)
{
memset(gdbregs, 0, sizeof(gdbregs));
}
RemoteGDB::~RemoteGDB()
{
if (event)
delete event;
}
string
RemoteGDB::name()
{
return system->name() + ".remote_gdb";
}
bool
RemoteGDB::isattached()
{ return attached; }
void
RemoteGDB::attach(int f)
{
fd = f;
event = new Event(this, fd, POLLIN);
pollQueue.schedule(event);
attached = true;
DPRINTFN("remote gdb attached\n");
}
void
RemoteGDB::detach()
{
attached = false;
close(fd);
fd = -1;
pollQueue.remove(event);
DPRINTFN("remote gdb detached\n");
}
const char *
gdb_command(char cmd)
{
switch (cmd) {
case KGDB_SIGNAL: return "KGDB_SIGNAL";
case KGDB_SET_BAUD: return "KGDB_SET_BAUD";
case KGDB_SET_BREAK: return "KGDB_SET_BREAK";
case KGDB_CONT: return "KGDB_CONT";
case KGDB_ASYNC_CONT: return "KGDB_ASYNC_CONT";
case KGDB_DEBUG: return "KGDB_DEBUG";
case KGDB_DETACH: return "KGDB_DETACH";
case KGDB_REG_R: return "KGDB_REG_R";
case KGDB_REG_W: return "KGDB_REG_W";
case KGDB_SET_THREAD: return "KGDB_SET_THREAD";
case KGDB_CYCLE_STEP: return "KGDB_CYCLE_STEP";
case KGDB_SIG_CYCLE_STEP: return "KGDB_SIG_CYCLE_STEP";
case KGDB_KILL: return "KGDB_KILL";
case KGDB_MEM_W: return "KGDB_MEM_W";
case KGDB_MEM_R: return "KGDB_MEM_R";
case KGDB_SET_REG: return "KGDB_SET_REG";
case KGDB_READ_REG: return "KGDB_READ_REG";
case KGDB_QUERY_VAR: return "KGDB_QUERY_VAR";
case KGDB_SET_VAR: return "KGDB_SET_VAR";
case KGDB_RESET: return "KGDB_RESET";
case KGDB_STEP: return "KGDB_STEP";
case KGDB_ASYNC_STEP: return "KGDB_ASYNC_STEP";
case KGDB_THREAD_ALIVE: return "KGDB_THREAD_ALIVE";
case KGDB_TARGET_EXIT: return "KGDB_TARGET_EXIT";
case KGDB_BINARY_DLOAD: return "KGDB_BINARY_DLOAD";
case KGDB_CLR_HW_BKPT: return "KGDB_CLR_HW_BKPT";
case KGDB_SET_HW_BKPT: return "KGDB_SET_HW_BKPT";
case KGDB_START: return "KGDB_START";
case KGDB_END: return "KGDB_END";
case KGDB_GOODP: return "KGDB_GOODP";
case KGDB_BADP: return "KGDB_BADP";
default: return "KGDB_UNKNOWN";
}
}
///////////////////////////////////////////////////////////
// RemoteGDB::acc
//
// Determine if the mapping at va..(va+len) is valid.
//
bool
RemoteGDB::acc(Addr va, size_t len)
{
Addr last_va;
va = TheISA::TruncPage(va);
last_va = TheISA::RoundPage(va + len);
do {
if (TheISA::IsK0Seg(va)) {
if (va < (TheISA::K0SegBase + pmem->size())) {
DPRINTF(GDBAcc, "acc: Mapping is valid K0SEG <= "
"%#x < K0SEG + size\n", va);
return true;
} else {
DPRINTF(GDBAcc, "acc: Mapping invalid %#x > K0SEG + size\n",
va);
return false;
}
}
/**
* This code says that all accesses to palcode (instruction and data)
* are valid since there isn't a va->pa mapping because palcode is
* accessed physically. At some point this should probably be cleaned up
* but there is no easy way to do it.
*/
if (AlphaISA::PcPAL(va) || va < 0x10000)
return true;
Addr ptbr = context->readMiscReg(AlphaISA::IPR_PALtemp20);
TheISA::PageTableEntry pte = kernel_pte_lookup(pmem, ptbr, va);
if (!pte.valid()) {
DPRINTF(GDBAcc, "acc: %#x pte is invalid\n", va);
return false;
}
va += TheISA::PageBytes;
} while (va < last_va);
DPRINTF(GDBAcc, "acc: %#x mapping is valid\n", va);
return true;
}
///////////////////////////////////////////////////////////
// RemoteGDB::signal
//
// Translate a trap number into a Unix-compatible signal number.
// (GDB only understands Unix signal numbers.)
//
int
RemoteGDB::signal(int type)
{
switch (type) {
case ALPHA_KENTRY_INT:
return (SIGTRAP);
case ALPHA_KENTRY_UNA:
return (SIGBUS);
case ALPHA_KENTRY_ARITH:
return (SIGFPE);
case ALPHA_KENTRY_IF:
return (SIGILL);
case ALPHA_KENTRY_MM:
return (SIGSEGV);
default:
panic("unknown signal type");
return 0;
}
}
///////////////////////////////////////////////////////////
// RemoteGDB::getregs
//
// Translate the kernel debugger register format into
// the GDB register format.
void
RemoteGDB::getregs()
{
memset(gdbregs, 0, sizeof(gdbregs));
gdbregs[KGDB_REG_PC] = context->readPC();
// @todo: Currently this is very Alpha specific.
if (AlphaISA::PcPAL(gdbregs[KGDB_REG_PC])) {
for (int i = 0; i < TheISA::NumIntArchRegs; ++i) {
gdbregs[i] = context->readIntReg(AlphaISA::reg_redir[i]);
}
} else {
for (int i = 0; i < TheISA::NumIntArchRegs; ++i) {
gdbregs[i] = context->readIntReg(i);
}
}
#ifdef KGDB_FP_REGS
for (int i = 0; i < TheISA::NumFloatArchRegs; ++i) {
gdbregs[i + KGDB_REG_F0] = context->readFloatRegInt(i);
}
#endif
}
///////////////////////////////////////////////////////////
// RemoteGDB::setregs
//
// Translate the GDB register format into the kernel
// debugger register format.
//
void
RemoteGDB::setregs()
{
// @todo: Currently this is very Alpha specific.
if (AlphaISA::PcPAL(gdbregs[KGDB_REG_PC])) {
for (int i = 0; i < TheISA::NumIntArchRegs; ++i) {
context->setIntReg(AlphaISA::reg_redir[i], gdbregs[i]);
}
} else {
for (int i = 0; i < TheISA::NumIntArchRegs; ++i) {
context->setIntReg(i, gdbregs[i]);
}
}
#ifdef KGDB_FP_REGS
for (int i = 0; i < TheISA::NumFloatArchRegs; ++i) {
context->setFloatRegInt(i, gdbregs[i + KGDB_REG_F0]);
}
#endif
context->regs.pc = gdbregs[KGDB_REG_PC];
}
void
RemoteGDB::setTempBreakpoint(TempBreakpoint &bkpt, Addr addr)
{
DPRINTF(GDBMisc, "setTempBreakpoint: addr=%#x\n", addr);
bkpt.address = addr;
insertHardBreak(addr, 4);
}
void
RemoteGDB::clearTempBreakpoint(TempBreakpoint &bkpt)
{
DPRINTF(GDBMisc, "setTempBreakpoint: addr=%#x\n",
bkpt.address);
removeHardBreak(bkpt.address, 4);
bkpt.address = 0;
}
void
RemoteGDB::clearSingleStep()
{
DPRINTF(GDBMisc, "clearSingleStep bt_addr=%#x nt_addr=%#x\n",
takenBkpt.address, notTakenBkpt.address);
if (takenBkpt.address != 0)
clearTempBreakpoint(takenBkpt);
if (notTakenBkpt.address != 0)
clearTempBreakpoint(notTakenBkpt);
}
void
RemoteGDB::setSingleStep()
{
Addr pc = context->regs.pc;
Addr npc, bpc;
bool set_bt = false;
npc = pc + sizeof(MachInst);
// User was stopped at pc, e.g. the instruction at pc was not
// executed.
MachInst inst = read<MachInst>(pc);
StaticInstPtr si(inst);
if (si->hasBranchTarget(pc, context, bpc)) {
// Don't bother setting a breakpoint on the taken branch if it
// is the same as the next pc
if (bpc != npc)
set_bt = true;
}
DPRINTF(GDBMisc, "setSingleStep bt_addr=%#x nt_addr=%#x\n",
takenBkpt.address, notTakenBkpt.address);
setTempBreakpoint(notTakenBkpt, npc);
if (set_bt)
setTempBreakpoint(takenBkpt, bpc);
}
/////////////////////////
//
//
uint8_t
RemoteGDB::getbyte()
{
uint8_t b;
::read(fd, &b, 1);
return b;
}
void
RemoteGDB::putbyte(uint8_t b)
{
::write(fd, &b, 1);
}
// Send a packet to gdb
void
RemoteGDB::send(const char *bp)
{
const char *p;
uint8_t csum, c;
DPRINTF(GDBSend, "send: %s\n", bp);
do {
p = bp;
putbyte(KGDB_START);
for (csum = 0; (c = *p); p++) {
putbyte(c);
csum += c;
}
putbyte(KGDB_END);
putbyte(i2digit(csum >> 4));
putbyte(i2digit(csum));
} while ((c = getbyte() & 0x7f) == KGDB_BADP);
}
// Receive a packet from gdb
int
RemoteGDB::recv(char *bp, int maxlen)
{
char *p;
int c, csum;
int len;
do {
p = bp;
csum = len = 0;
while ((c = getbyte()) != KGDB_START)
;
while ((c = getbyte()) != KGDB_END && len < maxlen) {
c &= 0x7f;
csum += c;
*p++ = c;
len++;
}
csum &= 0xff;
*p = '\0';
if (len >= maxlen) {
putbyte(KGDB_BADP);
continue;
}
csum -= digit2i(getbyte()) * 16;
csum -= digit2i(getbyte());
if (csum == 0) {
putbyte(KGDB_GOODP);
// Sequence present?
if (bp[2] == ':') {
putbyte(bp[0]);
putbyte(bp[1]);
len -= 3;
bcopy(bp + 3, bp, len);
}
break;
}
putbyte(KGDB_BADP);
} while (1);
DPRINTF(GDBRecv, "recv: %s: %s\n", gdb_command(*bp), bp);
return (len);
}
// Read bytes from kernel address space for debugger.
bool
RemoteGDB::read(Addr vaddr, size_t size, char *data)
{
static Addr lastaddr = 0;
static size_t lastsize = 0;
uint8_t *maddr;
if (vaddr < 10) {
DPRINTF(GDBRead, "read: reading memory location zero!\n");
vaddr = lastaddr + lastsize;
}
DPRINTF(GDBRead, "read: addr=%#x, size=%d", vaddr, size);
#if TRACING_ON
char *d = data;
size_t s = size;
#endif
lastaddr = vaddr;
lastsize = size;
size_t count = min((Addr)size,
VMPageSize - (vaddr & (VMPageSize - 1)));
maddr = vtomem(context, vaddr, count);
memcpy(data, maddr, count);
vaddr += count;
data += count;
size -= count;
while (size >= VMPageSize) {
maddr = vtomem(context, vaddr, count);
memcpy(data, maddr, VMPageSize);
vaddr += VMPageSize;
data += VMPageSize;
size -= VMPageSize;
}
if (size > 0) {
maddr = vtomem(context, vaddr, count);
memcpy(data, maddr, size);
}
#if TRACING_ON
if (DTRACE(GDBRead)) {
if (DTRACE(GDBExtra)) {
char buf[1024];
mem2hex(buf, d, s);
DPRINTFNR(": %s\n", buf);
} else
DPRINTFNR("\n");
}
#endif
return true;
}
// Write bytes to kernel address space for debugger.
bool
RemoteGDB::write(Addr vaddr, size_t size, const char *data)
{
static Addr lastaddr = 0;
static size_t lastsize = 0;
uint8_t *maddr;
if (vaddr < 10) {
DPRINTF(GDBWrite, "write: writing memory location zero!\n");
vaddr = lastaddr + lastsize;
}
if (DTRACE(GDBWrite)) {
DPRINTFN("write: addr=%#x, size=%d", vaddr, size);
if (DTRACE(GDBExtra)) {
char buf[1024];
mem2hex(buf, data, size);
DPRINTFNR(": %s\n", buf);
} else
DPRINTFNR("\n");
}
lastaddr = vaddr;
lastsize = size;
size_t count = min((Addr)size,
VMPageSize - (vaddr & (VMPageSize - 1)));
maddr = vtomem(context, vaddr, count);
memcpy(maddr, data, count);
vaddr += count;
data += count;
size -= count;
while (size >= VMPageSize) {
maddr = vtomem(context, vaddr, count);
memcpy(maddr, data, VMPageSize);
vaddr += VMPageSize;
data += VMPageSize;
size -= VMPageSize;
}
if (size > 0) {
maddr = vtomem(context, vaddr, count);
memcpy(maddr, data, size);
}
#ifdef IMB
alpha_pal_imb();
#endif
return true;
}
PCEventQueue *RemoteGDB::getPcEventQueue()
{
return &system->pcEventQueue;
}
RemoteGDB::HardBreakpoint::HardBreakpoint(RemoteGDB *_gdb, Addr pc)
: PCEvent(_gdb->getPcEventQueue(), "HardBreakpoint Event", pc),
gdb(_gdb), refcount(0)
{
DPRINTF(GDBMisc, "creating hardware breakpoint at %#x\n", evpc);
}
void
RemoteGDB::HardBreakpoint::process(ExecContext *xc)
{
DPRINTF(GDBMisc, "handling hardware breakpoint at %#x\n", pc());
if (xc == gdb->context)
gdb->trap(ALPHA_KENTRY_INT);
}
bool
RemoteGDB::insertSoftBreak(Addr addr, size_t len)
{
if (len != sizeof(MachInst))
panic("invalid length\n");
return insertHardBreak(addr, len);
}
bool
RemoteGDB::removeSoftBreak(Addr addr, size_t len)
{
if (len != sizeof(MachInst))
panic("invalid length\n");
return removeHardBreak(addr, len);
}
bool
RemoteGDB::insertHardBreak(Addr addr, size_t len)
{
if (len != sizeof(MachInst))
panic("invalid length\n");
DPRINTF(GDBMisc, "inserting hardware breakpoint at %#x\n", addr);
HardBreakpoint *&bkpt = hardBreakMap[addr];
if (bkpt == 0)
bkpt = new HardBreakpoint(this, addr);
bkpt->refcount++;
return true;
}
bool
RemoteGDB::removeHardBreak(Addr addr, size_t len)
{
if (len != sizeof(MachInst))
panic("invalid length\n");
DPRINTF(GDBMisc, "removing hardware breakpoint at %#x\n", addr);
break_iter_t i = hardBreakMap.find(addr);
if (i == hardBreakMap.end())
return false;
HardBreakpoint *hbp = (*i).second;
if (--hbp->refcount == 0) {
delete hbp;
hardBreakMap.erase(i);
}
return true;
}
const char *
break_type(char c)
{
switch(c) {
case '0': return "software breakpoint";
case '1': return "hardware breakpoint";
case '2': return "write watchpoint";
case '3': return "read watchpoint";
case '4': return "access watchpoint";
default: return "unknown breakpoint/watchpoint";
}
}
// This function does all command processing for interfacing to a
// remote gdb. Note that the error codes are ignored by gdb at
// present, but might eventually become meaningful. (XXX) It might
// makes sense to use POSIX errno values, because that is what the
// gdb/remote.c functions want to return.
bool
RemoteGDB::trap(int type)
{
uint64_t val;
size_t datalen, len;
char data[KGDB_BUFLEN + 1];
char buffer[sizeof(gdbregs) * 2 + 256];
char temp[KGDB_BUFLEN];
const char *p;
char command, subcmd;
string var;
bool ret;
if (!attached)
return false;
DPRINTF(GDBMisc, "trap: PC=%#x NPC=%#x\n",
context->regs.pc, context->regs.npc);
clearSingleStep();
/*
* The first entry to this function is normally through
* a breakpoint trap in kgdb_connect(), in which case we
* must advance past the breakpoint because gdb will not.
*
* On the first entry here, we expect that gdb is not yet
* listening to us, so just enter the interaction loop.
* After the debugger is "active" (connected) it will be
* waiting for a "signaled" message from us.
*/
if (!active)
active = true;
else
// Tell remote host that an exception has occurred.
snprintf((char *)buffer, sizeof(buffer), "S%02x", signal(type));
send(buffer);
// Stick frame regs into our reg cache.
getregs();
for (;;) {
datalen = recv(data, sizeof(data));
data[sizeof(data) - 1] = 0; // Sentinel
command = data[0];
subcmd = 0;
p = data + 1;
switch (command) {
case KGDB_SIGNAL:
// if this command came from a running gdb, answer it --
// the other guy has no way of knowing if we're in or out
// of this loop when he issues a "remote-signal".
snprintf((char *)buffer, sizeof(buffer), "S%02x", signal(type));
send(buffer);
continue;
case KGDB_REG_R:
if (2 * sizeof(gdbregs) > sizeof(buffer))
panic("buffer too small");
mem2hex(buffer, gdbregs, sizeof(gdbregs));
send(buffer);
continue;
case KGDB_REG_W:
p = hex2mem(gdbregs, p, sizeof(gdbregs));
if (p == NULL || *p != '\0')
send("E01");
else {
setregs();
send("OK");
}
continue;
#if 0
case KGDB_SET_REG:
val = hex2i(&p);
if (*p++ != '=') {
send("E01");
continue;
}
if (val < 0 && val >= KGDB_NUMREGS) {
send("E01");
continue;
}
gdbregs[val] = hex2i(&p);
setregs();
send("OK");
continue;
#endif
case KGDB_MEM_R:
val = hex2i(&p);
if (*p++ != ',') {
send("E02");
continue;
}
len = hex2i(&p);
if (*p != '\0') {
send("E03");
continue;
}
if (len > sizeof(buffer)) {
send("E04");
continue;
}
if (!acc(val, len)) {
send("E05");
continue;
}
if (read(val, (size_t)len, (char *)buffer)) {
mem2hex(temp, buffer, len);
send(temp);
} else {
send("E05");
}
continue;
case KGDB_MEM_W:
val = hex2i(&p);
if (*p++ != ',') {
send("E06");
continue;
}
len = hex2i(&p);
if (*p++ != ':') {
send("E07");
continue;
}
if (len > datalen - (p - data)) {
send("E08");
continue;
}
p = hex2mem(buffer, p, sizeof(buffer));
if (p == NULL) {
send("E09");
continue;
}
if (!acc(val, len)) {
send("E0A");
continue;
}
if (write(val, (size_t)len, (char *)buffer))
send("OK");
else
send("E0B");
continue;
case KGDB_SET_THREAD:
subcmd = *p++;
val = hex2i(&p);
if (val == 0)
send("OK");
else
send("E01");
continue;
case KGDB_DETACH:
case KGDB_KILL:
active = false;
clearSingleStep();
detach();
goto out;
case KGDB_ASYNC_CONT:
subcmd = hex2i(&p);
if (*p++ == ';') {
val = hex2i(&p);
context->regs.pc = val;
context->regs.npc = val + sizeof(MachInst);
}
clearSingleStep();
goto out;
case KGDB_CONT:
if (p - data < datalen) {
val = hex2i(&p);
context->regs.pc = val;
context->regs.npc = val + sizeof(MachInst);
}
clearSingleStep();
goto out;
case KGDB_ASYNC_STEP:
subcmd = hex2i(&p);
if (*p++ == ';') {
val = hex2i(&p);
context->regs.pc = val;
context->regs.npc = val + sizeof(MachInst);
}
setSingleStep();
goto out;
case KGDB_STEP:
if (p - data < datalen) {
val = hex2i(&p);
context->regs.pc = val;
context->regs.npc = val + sizeof(MachInst);
}
setSingleStep();
goto out;
case KGDB_CLR_HW_BKPT:
subcmd = *p++;
if (*p++ != ',') send("E0D");
val = hex2i(&p);
if (*p++ != ',') send("E0D");
len = hex2i(&p);
DPRINTF(GDBMisc, "clear %s, addr=%#x, len=%d\n",
break_type(subcmd), val, len);
ret = false;
switch (subcmd) {
case '0': // software breakpoint
ret = removeSoftBreak(val, len);
break;
case '1': // hardware breakpoint
ret = removeHardBreak(val, len);
break;
case '2': // write watchpoint
case '3': // read watchpoint
case '4': // access watchpoint
default: // unknown
send("");
break;
}
send(ret ? "OK" : "E0C");
continue;
case KGDB_SET_HW_BKPT:
subcmd = *p++;
if (*p++ != ',') send("E0D");
val = hex2i(&p);
if (*p++ != ',') send("E0D");
len = hex2i(&p);
DPRINTF(GDBMisc, "set %s, addr=%#x, len=%d\n",
break_type(subcmd), val, len);
ret = false;
switch (subcmd) {
case '0': // software breakpoint
ret = insertSoftBreak(val, len);
break;
case '1': // hardware breakpoint
ret = insertHardBreak(val, len);
break;
case '2': // write watchpoint
case '3': // read watchpoint
case '4': // access watchpoint
default: // unknown
send("");
break;
}
send(ret ? "OK" : "E0C");
continue;
case KGDB_QUERY_VAR:
var = string(p, datalen - 1);
if (var == "C")
send("QC0");
else
send("");
continue;
case KGDB_SET_BAUD:
case KGDB_SET_BREAK:
case KGDB_DEBUG:
case KGDB_CYCLE_STEP:
case KGDB_SIG_CYCLE_STEP:
case KGDB_READ_REG:
case KGDB_SET_VAR:
case KGDB_RESET:
case KGDB_THREAD_ALIVE:
case KGDB_TARGET_EXIT:
case KGDB_BINARY_DLOAD:
// Unsupported command
DPRINTF(GDBMisc, "Unsupported command: %s\n",
gdb_command(command));
DDUMP(GDBMisc, (uint8_t *)data, datalen);
send("");
continue;
default:
// Unknown command.
DPRINTF(GDBMisc, "Unknown command: %c(%#x)\n",
command, command);
send("");
continue;
}
}
out:
return true;
}
// Convert a hex digit into an integer.
// This returns -1 if the argument passed is no valid hex digit.
int
digit2i(char c)
{
if (c >= '0' && c <= '9')
return (c - '0');
else if (c >= 'a' && c <= 'f')
return (c - 'a' + 10);
else if (c >= 'A' && c <= 'F')
return (c - 'A' + 10);
else
return (-1);
}
// Convert the low 4 bits of an integer into an hex digit.
char
i2digit(int n)
{
return ("0123456789abcdef"[n & 0x0f]);
}
// Convert a byte array into an hex string.
void
mem2hex(void *vdst, const void *vsrc, int len)
{
char *dst = (char *)vdst;
const char *src = (const char *)vsrc;
while (len--) {
*dst++ = i2digit(*src >> 4);
*dst++ = i2digit(*src++);
}
*dst = '\0';
}
// Convert an hex string into a byte array.
// This returns a pointer to the character following the last valid
// hex digit. If the string ends in the middle of a byte, NULL is
// returned.
const char *
hex2mem(void *vdst, const char *src, int maxlen)
{
char *dst = (char *)vdst;
int msb, lsb;
while (*src && maxlen--) {
msb = digit2i(*src++);
if (msb < 0)
return (src - 1);
lsb = digit2i(*src++);
if (lsb < 0)
return (NULL);
*dst++ = (msb << 4) | lsb;
}
return (src);
}
// Convert an hex string into an integer.
// This returns a pointer to the character following the last valid
// hex digit.
Addr
hex2i(const char **srcp)
{
const char *src = *srcp;
Addr r = 0;
int nibble;
while ((nibble = digit2i(*src)) >= 0) {
r *= 16;
r += nibble;
src++;
}
*srcp = src;
return (r);
}