target *target_attach_n(int n, struct target_controller *tc)
{
target *t;
int i;
for(t = target_list, i = 1; t; t = t->next, i++)
if(i == n)
return target_attach(t, tc);
return NULL;
}
void
gdb_main(void)
{
int size;
bool single_step = false;
char last_activity = 0;
DEBUG("Entring GDB protocol main loop\n");
/* GDB protocol main loop */
while(1) {
SET_IDLE_STATE(1);
size = gdb_getpacket(pbuf, BUF_SIZE);
SET_IDLE_STATE(0);
continue_activity:
switch(pbuf[0]) {
/* Implementation of these is mandatory! */
case 'g': { /* 'g': Read general registers */
ERROR_IF_NO_TARGET();
uint8_t arm_regs[target_regs_size(cur_target)];
target_regs_read(cur_target, arm_regs);
gdb_putpacket(hexify(pbuf, arm_regs, sizeof(arm_regs)),
sizeof(arm_regs) * 2);
break;
}
case 'm': { /* 'm addr,len': Read len bytes from addr */
uint32_t addr, len;
ERROR_IF_NO_TARGET();
sscanf(pbuf, "m%" SCNx32 ",%" SCNx32, &addr, &len);
DEBUG("m packet: addr = %" PRIx32 ", len = %" PRIx32 "\n", addr, len);
uint8_t mem[len];
target_mem_read(cur_target, mem, addr, len);
if(target_check_error(cur_target))
gdb_putpacketz("E01");
else
gdb_putpacket(hexify(pbuf, mem, len), len*2);
break;
}
case 'G': { /* 'G XX': Write general registers */
ERROR_IF_NO_TARGET();
uint8_t arm_regs[target_regs_size(cur_target)];
unhexify(arm_regs, &pbuf[1], sizeof(arm_regs));
target_regs_write(cur_target, arm_regs);
gdb_putpacketz("OK");
break;
}
case 'M': { /* 'M addr,len:XX': Write len bytes to addr */
uint32_t addr, len;
int hex;
ERROR_IF_NO_TARGET();
sscanf(pbuf, "M%" SCNx32 ",%" SCNx32 ":%n", &addr, &len, &hex);
DEBUG("M packet: addr = %" PRIx32 ", len = %" PRIx32 "\n", addr, len);
uint8_t mem[len];
unhexify(mem, pbuf + hex, len);
target_mem_write(cur_target, addr, mem, len);
if(target_check_error(cur_target))
gdb_putpacketz("E01");
else
gdb_putpacketz("OK");
break;
}
case 's': /* 's [addr]': Single step [start at addr] */
single_step = true;
// Fall through to resume target
case 'c': /* 'c [addr]': Continue [at addr] */
if(!cur_target) {
gdb_putpacketz("X1D");
break;
}
target_halt_resume(cur_target, single_step);
SET_RUN_STATE(1);
single_step = false;
// Fall through to wait for target halt
case '?': { /* '?': Request reason for target halt */
/* This packet isn't documented as being mandatory,
* but GDB doesn't work without it. */
uint32_t watch_addr;
int sig;
if(!cur_target) {
/* Report "target exited" if no target */
gdb_putpacketz("W00");
break;
}
last_activity = pbuf[0];
/* Wait for target halt */
while(!(sig = target_halt_wait(cur_target))) {
unsigned char c = gdb_if_getchar_to(0);
if((c == '\x03') || (c == '\x04')) {
target_halt_request(cur_target);
last_activity = 's';
}
}
SET_RUN_STATE(0);
/* Negative signal indicates we're in a syscall */
if (sig < 0)
break;
/* Target disappeared */
if (cur_target == NULL) {
gdb_putpacket_f("X%02X", sig);
break;
}
/* Report reason for halt */
if(target_check_hw_wp(cur_target, &watch_addr)) {
/* Watchpoint hit */
gdb_putpacket_f("T%02Xwatch:%08X;", sig, watch_addr);
} else {
gdb_putpacket_f("T%02X", sig);
}
break;
}
case 'F': { /* Semihosting call finished */
int retcode, errcode, items;
char c, *p;
if (pbuf[1] == '-')
p = &pbuf[2];
else
p = &pbuf[1];
items = sscanf(p, "%x,%x,%c", &retcode, &errcode, &c);
if (pbuf[1] == '-')
retcode = -retcode;
target_hostio_reply(cur_target, retcode, errcode);
/* if break is requested */
if (items == 3 && c == 'C') {
gdb_putpacketz("T02");
break;
}
pbuf[0] = last_activity;
goto continue_activity;
}
/* Optional GDB packet support */
case '!': /* Enable Extended GDB Protocol. */
/* This doesn't do anything, we support the extended
* protocol anyway, but GDB will never send us a 'R'
* packet unless we answer 'OK' here.
*/
gdb_putpacketz("OK");
break;
case 0x04:
case 'D': /* GDB 'detach' command. */
if(cur_target)
target_detach(cur_target);
last_target = cur_target;
cur_target = NULL;
gdb_putpacketz("OK");
break;
case 'k': /* Kill the target */
if(cur_target) {
target_reset(cur_target);
target_detach(cur_target);
last_target = cur_target;
cur_target = NULL;
}
break;
case 'r': /* Reset the target system */
case 'R': /* Restart the target program */
if(cur_target)
target_reset(cur_target);
else if(last_target) {
cur_target = target_attach(last_target,
gdb_target_destroy_callback);
target_reset(cur_target);
}
break;
case 'X': { /* 'X addr,len:XX': Write binary data to addr */
uint32_t addr, len;
int bin;
ERROR_IF_NO_TARGET();
sscanf(pbuf, "X%" SCNx32 ",%" SCNx32 ":%n", &addr, &len, &bin);
DEBUG("X packet: addr = %" PRIx32 ", len = %" PRIx32 "\n", addr, len);
target_mem_write(cur_target, addr, pbuf+bin, len);
if(target_check_error(cur_target))
gdb_putpacketz("E01");
else
gdb_putpacketz("OK");
break;
}
case 'q': /* General query packet */
handle_q_packet(pbuf, size);
break;
case 'v': /* General query packet */
handle_v_packet(pbuf, size);
break;
/* These packet implement hardware break-/watchpoints */
case 'Z': /* Z type,addr,len: Set breakpoint packet */
case 'z': /* z type,addr,len: Clear breakpoint packet */
ERROR_IF_NO_TARGET();
handle_z_packet(pbuf, size);
break;
default: /* Packet not implemented */
DEBUG("*** Unsupported packet: %s\n", pbuf);
gdb_putpacketz("");
}
}
}
static void
handle_v_packet(char *packet, int plen)
{
unsigned long addr, len;
int bin;
static uint8_t flash_mode = 0;
if (sscanf(packet, "vAttach;%08lx", &addr) == 1) {
/* Attach to remote target processor */
target *t;
uint32_t i;
for(t = target_list, i = 1; t; t = t->next, i++)
if(i == addr) {
cur_target = target_attach(t,
gdb_target_destroy_callback);
break;
}
if(cur_target)
gdb_putpacketz("T05");
else
gdb_putpacketz("E01");
} else if (!strcmp(packet, "vRun;")) {
/* Run target program. For us (embedded) this means reset. */
if(cur_target) {
target_reset(cur_target);
gdb_putpacketz("T05");
} else if(last_target) {
cur_target = target_attach(last_target,
gdb_target_destroy_callback);
/* If we were able to attach to the target again */
if (cur_target) {
target_reset(cur_target);
gdb_putpacketz("T05");
} else gdb_putpacketz("E01");
} else gdb_putpacketz("E01");
} else if (sscanf(packet, "vFlashErase:%08lx,%08lx", &addr, &len) == 2) {
/* Erase Flash Memory */
DEBUG("Flash Erase %08lX %08lX\n", addr, len);
if(!cur_target) { gdb_putpacketz("EFF"); return; }
if(!flash_mode) {
/* Reset target if first flash command! */
/* This saves us if we're interrupted in IRQ context */
target_reset(cur_target);
flash_mode = 1;
}
if(target_flash_erase(cur_target, addr, len) == 0)
gdb_putpacketz("OK");
else
gdb_putpacketz("EFF");
} else if (sscanf(packet, "vFlashWrite:%08lx:%n", &addr, &bin) == 1) {
/* Write Flash Memory */
len = plen - bin;
DEBUG("Flash Write %08lX %08lX\n", addr, len);
if(cur_target && target_flash_write(cur_target, addr, (void*)packet + bin, len) == 0)
gdb_putpacketz("OK");
else
gdb_putpacketz("EFF");
} else if (!strcmp(packet, "vFlashDone")) {
/* Commit flash operations. */
gdb_putpacketz(target_flash_done(cur_target) ? "EFF" : "OK");
flash_mode = 0;
} else {
DEBUG("*** Unsupported packet: %s\n", packet);
gdb_putpacket("", 0);
}
}
static void
handle_q_packet(char *packet, int len)
{
uint32_t addr, alen;
if(!strncmp(packet, "qRcmd,", 6)) {
char *data;
int datalen;
/* calculate size and allocate buffer for command */
datalen = (len - 6) / 2;
data = alloca(datalen+1);
/* dehexify command */
unhexify(data, packet+6, datalen);
data[datalen] = 0; /* add terminating null */
int c = command_process(cur_target, data);
if(c < 0)
gdb_putpacketz("");
else if(c == 0)
gdb_putpacketz("OK");
else
gdb_putpacketz("E");
} else if (!strncmp (packet, "qSupported", 10)) {
/* Query supported protocol features */
gdb_putpacket_f("PacketSize=%X;qXfer:memory-map:read+;qXfer:features:read+", BUF_SIZE);
} else if (strncmp (packet, "qXfer:memory-map:read::", 23) == 0) {
/* Read target XML memory map */
if((!cur_target) && last_target) {
/* Attach to last target if detached. */
cur_target = target_attach(last_target,
gdb_target_destroy_callback);
}
if (!cur_target) {
gdb_putpacketz("E01");
return;
}
handle_q_string_reply(target_mem_map(cur_target), packet + 23);
} else if (strncmp (packet, "qXfer:features:read:target.xml:", 31) == 0) {
/* Read target description */
if((!cur_target) && last_target) {
/* Attach to last target if detached. */
cur_target = target_attach(last_target,
gdb_target_destroy_callback);
}
if (!cur_target) {
gdb_putpacketz("E01");
return;
}
handle_q_string_reply(target_tdesc(cur_target), packet + 31);
} else if (sscanf(packet, "qCRC:%" PRIx32 ",%" PRIx32, &addr, &alen) == 2) {
if(!cur_target) {
gdb_putpacketz("E01");
return;
}
gdb_putpacket_f("C%lx", generic_crc32(cur_target, addr, alen));
} else {
DEBUG("*** Unsupported packet: %s\n", packet);
gdb_putpacket("", 0);
}
}
int gdb_main_loop(struct target_controller *tc, bool in_syscall)
{
int size;
bool single_step = false;
/* GDB protocol main loop */
while(1) {
SET_IDLE_STATE(1);
size = gdb_getpacket(pbuf, BUF_SIZE);
SET_IDLE_STATE(0);
switch(pbuf[0]) {
/* Implementation of these is mandatory! */
case 'g': { /* 'g': Read general registers */
ERROR_IF_NO_TARGET();
uint8_t arm_regs[target_regs_size(cur_target)];
target_regs_read(cur_target, arm_regs);
gdb_putpacket(hexify(pbuf, arm_regs, sizeof(arm_regs)),
sizeof(arm_regs) * 2);
break;
}
case 'm': { /* 'm addr,len': Read len bytes from addr */
uint32_t addr, len;
ERROR_IF_NO_TARGET();
sscanf(pbuf, "m%" SCNx32 ",%" SCNx32, &addr, &len);
if (len > sizeof(pbuf) / 2) {
gdb_putpacketz("E02");
break;
}
DEBUG("m packet: addr = %" PRIx32 ", len = %" PRIx32 "\n", addr, len);
uint8_t mem[len];
if (target_mem_read(cur_target, mem, addr, len))
gdb_putpacketz("E01");
else
gdb_putpacket(hexify(pbuf, mem, len), len*2);
break;
}
case 'G': { /* 'G XX': Write general registers */
ERROR_IF_NO_TARGET();
uint8_t arm_regs[target_regs_size(cur_target)];
unhexify(arm_regs, &pbuf[1], sizeof(arm_regs));
target_regs_write(cur_target, arm_regs);
gdb_putpacketz("OK");
break;
}
case 'M': { /* 'M addr,len:XX': Write len bytes to addr */
uint32_t addr, len;
int hex;
ERROR_IF_NO_TARGET();
sscanf(pbuf, "M%" SCNx32 ",%" SCNx32 ":%n", &addr, &len, &hex);
if (len > (unsigned)(size - hex) / 2) {
gdb_putpacketz("E02");
break;
}
DEBUG("M packet: addr = %" PRIx32 ", len = %" PRIx32 "\n", addr, len);
uint8_t mem[len];
unhexify(mem, pbuf + hex, len);
if (target_mem_write(cur_target, addr, mem, len))
gdb_putpacketz("E01");
else
gdb_putpacketz("OK");
break;
}
case 's': /* 's [addr]': Single step [start at addr] */
single_step = true;
/* fall through */
case 'c': /* 'c [addr]': Continue [at addr] */
if(!cur_target) {
gdb_putpacketz("X1D");
break;
}
target_halt_resume(cur_target, single_step);
SET_RUN_STATE(1);
single_step = false;
/* fall through */
case '?': { /* '?': Request reason for target halt */
/* This packet isn't documented as being mandatory,
* but GDB doesn't work without it. */
target_addr watch;
enum target_halt_reason reason;
if(!cur_target) {
/* Report "target exited" if no target */
gdb_putpacketz("W00");
break;
}
/* Wait for target halt */
while(!(reason = target_halt_poll(cur_target, &watch))) {
unsigned char c = gdb_if_getchar_to(0);
if((c == '\x03') || (c == '\x04')) {
target_halt_request(cur_target);
}
}
SET_RUN_STATE(0);
/* Translate reason to GDB signal */
switch (reason) {
case TARGET_HALT_ERROR:
gdb_putpacket_f("X%02X", GDB_SIGLOST);
morse("TARGET LOST.", true);
break;
case TARGET_HALT_REQUEST:
gdb_putpacket_f("T%02X", GDB_SIGINT);
break;
case TARGET_HALT_WATCHPOINT:
gdb_putpacket_f("T%02Xwatch:%08X;", GDB_SIGTRAP, watch);
break;
case TARGET_HALT_FAULT:
gdb_putpacket_f("T%02X", GDB_SIGSEGV);
break;
default:
gdb_putpacket_f("T%02X", GDB_SIGTRAP);
}
break;
}
case 'F': /* Semihosting call finished */
if (in_syscall) {
return hostio_reply(tc, pbuf, size);
} else {
DEBUG("*** F packet when not in syscall! '%s'\n", pbuf);
gdb_putpacketz("");
}
break;
/* Optional GDB packet support */
case '!': /* Enable Extended GDB Protocol. */
/* This doesn't do anything, we support the extended
* protocol anyway, but GDB will never send us a 'R'
* packet unless we answer 'OK' here.
*/
gdb_putpacketz("OK");
break;
case 0x04:
case 'D': /* GDB 'detach' command. */
if(cur_target)
target_detach(cur_target);
last_target = cur_target;
cur_target = NULL;
gdb_putpacketz("OK");
break;
case 'k': /* Kill the target */
if(cur_target) {
target_reset(cur_target);
target_detach(cur_target);
last_target = cur_target;
cur_target = NULL;
}
break;
case 'r': /* Reset the target system */
case 'R': /* Restart the target program */
if(cur_target)
target_reset(cur_target);
else if(last_target) {
cur_target = target_attach(last_target,
&gdb_controller);
target_reset(cur_target);
}
break;
case 'X': { /* 'X addr,len:XX': Write binary data to addr */
uint32_t addr, len;
int bin;
ERROR_IF_NO_TARGET();
sscanf(pbuf, "X%" SCNx32 ",%" SCNx32 ":%n", &addr, &len, &bin);
if (len > (unsigned)(size - bin)) {
gdb_putpacketz("E02");
break;
}
DEBUG("X packet: addr = %" PRIx32 ", len = %" PRIx32 "\n", addr, len);
if (target_mem_write(cur_target, addr, pbuf+bin, len))
gdb_putpacketz("E01");
else
gdb_putpacketz("OK");
break;
}
case 'q': /* General query packet */
handle_q_packet(pbuf, size);
break;
case 'v': /* General query packet */
handle_v_packet(pbuf, size);
break;
/* These packet implement hardware break-/watchpoints */
case 'Z': /* Z type,addr,len: Set breakpoint packet */
case 'z': /* z type,addr,len: Clear breakpoint packet */
ERROR_IF_NO_TARGET();
handle_z_packet(pbuf, size);
break;
default: /* Packet not implemented */
DEBUG("*** Unsupported packet: %s\n", pbuf);
gdb_putpacketz("");
}
}
}