bool cortexa_attach(target *t)
{
struct cortexa_priv *priv = t->priv;
int tries;
/* Clear any pending fault condition */
target_check_error(t);
/* Enable halting debug mode */
uint32_t dbgdscr = apb_read(t, DBGDSCR);
dbgdscr |= DBGDSCR_HDBGEN | DBGDSCR_ITREN;
dbgdscr = (dbgdscr & ~DBGDSCR_EXTDCCMODE_MASK) | DBGDSCR_EXTDCCMODE_STALL;
apb_write(t, DBGDSCR, dbgdscr);
DEBUG("DBGDSCR = 0x%08"PRIx32"\n", dbgdscr);
target_halt_request(t);
tries = 10;
while(!platform_srst_get_val() && !target_halt_poll(t, NULL) && --tries)
platform_delay(200);
if(!tries)
return false;
/* Clear any stale breakpoints */
for(unsigned i = 0; i < priv->hw_breakpoint_max; i++) {
apb_write(t, DBGBCR(i), 0);
}
priv->hw_breakpoint_mask = 0;
priv->bcr0 = 0;
platform_srst_set_val(false);
return true;
}
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("");
}
}
}
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("");
}
}
}