git.gag.com Git - fw/stlink/blob - src/gdb-server.c

   1 /* -*- tab-width:8 -*- */
   2
   3 /*
   4  Copyright (C)  2011 Peter Zotov <whitequark@whitequark.org>
   5  Use of this source code is governed by a BSD-style
   6  license that can be found in the LICENSE file.
   7 */
   8
   9 #include <stdio.h>
  10 #include <string.h>
  11 #include <stdlib.h>
  12 #include <unistd.h>
  13 #include <sys/types.h>
  14 #include <sys/socket.h>
  15 #include <netinet/in.h>
  16 #include <arpa/inet.h>
  17 #include "gdb-remote.h"
  18 #include "stlink-hw.h"
  19
  20 static const char hex[] = "0123456789abcdef";
  21
  22 static const char* current_memory_map = NULL;
  23
  24 struct chip_params {
  25         uint32_t chip_id;
  26         char* description;
  27         uint32_t flash_size, flash_pagesize;
  28         uint32_t sram_size;
  29         uint32_t bootrom_base, bootrom_size;
  30 } const devices[] = {
  31         { 0x412, "Low-density device",
  32           0x8000,   0x400, 0x2800,  0x1ffff000, 0x800  },
  33         { 0x410, "Medium-density device",
  34           0x20000,  0x400, 0x5000,  0x1ffff000, 0x800  },
  35         { 0x414, "High-density device",
  36           0x80000,  0x800, 0x10000, 0x1ffff000, 0x800  },
  37         { 0x418, "Connectivity line device",
  38           0x40000,  0x800, 0x10000, 0x1fffb000, 0x4800 },
  39         { 0x420, "Medium-density value line device",
  40           0x20000,  0x400, 0x2000,  0x1ffff000, 0x800  },
  41         { 0x428, "High-density value line device",
  42           0x80000,  0x800, 0x8000,  0x1ffff000, 0x800  },
  43         { 0x430, "XL-density device",
  44           0x100000, 0x800, 0x18000, 0x1fffe000, 0x1800 },
  45         { 0 }
  46 };
  47
  48 int serve(struct stlink* sl, int port);
  49 char* make_memory_map(const struct chip_params *params);
  50
  51 int main(int argc, char** argv) {
  52         if(argc != 3) {
  53                 fprintf(stderr, "Usage: %s <port> /dev/sgX\n", argv[0]);
  54                 return 1;
  55         }
  56
  57         struct stlink *sl = stlink_quirk_open(argv[2], 0);
  58         if (sl == NULL)
  59                 return 1;
  60
  61         if(stlink_current_mode(sl) != STLINK_DEV_DEBUG_MODE)
  62                 stlink_enter_swd_mode(sl);
  63
  64         uint32_t chip_id;
  65
  66         stlink_read_mem32(sl, 0xE0042000, 4);
  67         chip_id = sl->q_buf[0] | (sl->q_buf[1] << 8) | (sl->q_buf[2] << 16) |
  68                 (sl->q_buf[3] << 24);
  69
  70         printf("Chip ID is %08x.\n", chip_id);
  71
  72         const struct chip_params* params = NULL;
  73
  74         for(int i = 0; i < sizeof(devices) / sizeof(devices[0]); i++) {
  75                 if(devices[i].chip_id == chip_id) {
  76                         params = &devices[i];
  77                         break;
  78                 }
  79         }
  80
  81         if(params == NULL) {
  82                 fprintf(stderr, "Cannot recognize the connected device!\n");
  83                 return 0;
  84         }
  85
  86         printf("Device connected: %s\n", params->description);
  87         printf("Device parameters: SRAM: 0x%x bytes, Flash: 0x%x bytes in pages of %x bytes\n",
  88                 params->sram_size, params->flash_size, params->flash_pagesize);
  89
  90         current_memory_map = make_memory_map(params);
  91
  92         int port = atoi(argv[1]);
  93
  94         while(serve(sl, port) == 0);
  95
  96         stlink_close(sl);
  97
  98         return 0;
  99 }
 100
 101 static const char* const memory_map_template =
 102   "<?xml version=\"1.0\"?>"
 103   "<!DOCTYPE memory-map PUBLIC \"+//IDN gnu.org//DTD GDB Memory Map V1.0//EN\""
 104   "     \"http://sourceware.org/gdb/gdb-memory-map.dtd\">"
 105   "<memory-map>"
 106   "  <memory type=\"rom\" start=\"0x00000000\" length=\"0x%x\"/>"       // code = sram, bootrom or flash; flash is bigger
 107   "  <memory type=\"ram\" start=\"0x20000000\" length=\"0x%x\"/>"       // sram 8k
 108   "  <memory type=\"flash\" start=\"0x08000000\" length=\"0x%x\">"
 109   "    <property name=\"blocksize\">0x%x</property>"
 110   "  </memory>"
 111   "  <memory type=\"ram\" start=\"0x40000000\" length=\"0x1fffffff\"/>" // peripheral regs
 112   "  <memory type=\"ram\" start=\"0xe0000000\" length=\"0x1fffffff\"/>" // cortex regs
 113   "  <memory type=\"rom\" start=\"0x%08x\" length=\"0x%x\"/>"           // bootrom
 114   "  <memory type=\"rom\" start=\"0x1ffff800\" length=\"0x8\"/>"        // option byte area
 115   "</memory-map>";
 116
 117 char* make_memory_map(const struct chip_params *params) {
 118         /* This will be freed in serve() */
 119         char* map = malloc(4096);
 120         map[0] = '\0';
 121
 122         snprintf(map, 4096, memory_map_template,
 123                         params->flash_size,
 124                         params->sram_size,
 125                         params->flash_size, params->flash_pagesize,
 126                         params->bootrom_base, params->bootrom_size);
 127
 128         return map;
 129 }
 130
 131 #define CODE_BREAK_NUM  6
 132
 133 #define CODE_BREAK_LOW  0x01
 134 #define CODE_BREAK_HIGH 0x02
 135
 136 struct code_hw_breakpoint {
 137         stm32_addr_t addr;
 138         int          type;
 139 };
 140
 141 struct code_hw_breakpoint code_breaks[CODE_BREAK_NUM];
 142
 143 static void init_code_breakpoints(struct stlink* sl) {
 144         memset(sl->q_buf, 0, 4);
 145         sl->q_buf[0] = 0x03; // KEY | ENABLE
 146         stlink_write_mem32(sl, 0xe0002000, 4);
 147
 148         memset(sl->q_buf, 0, 4);
 149         for(int i = 0; i < CODE_BREAK_NUM; i++) {
 150                 code_breaks[i].type = 0;
 151                 stlink_write_mem32(sl, 0xe0002008 + i * 4, 4);
 152         }
 153 }
 154
 155 static int update_code_breakpoint(struct stlink* sl, stm32_addr_t addr, int set) {
 156         stm32_addr_t fpb_addr = addr & ~0x3;
 157         int type = addr & 0x2 ? CODE_BREAK_HIGH : CODE_BREAK_LOW;
 158
 159         if(addr & 1) {
 160                 fprintf(stderr, "update_code_breakpoint: unaligned address %08x\n", addr);
 161                 return -1;
 162         }
 163
 164         int id = -1;
 165         for(int i = 0; i < CODE_BREAK_NUM; i++) {
 166                 if(fpb_addr == code_breaks[i].addr ||
 167                         (set && code_breaks[i].type == 0)) {
 168                         id = i;
 169                         break;
 170                 }
 171         }
 172
 173         if(id == -1) {
 174                 if(set) return -1; // Free slot not found
 175                 else    return 0;  // Breakpoint is already removed
 176         }
 177
 178         struct code_hw_breakpoint* brk = &code_breaks[id];
 179
 180         brk->addr = fpb_addr;
 181
 182         if(set) brk->type |= type;
 183         else    brk->type &= ~type;
 184
 185         memset(sl->q_buf, 0, 4);
 186
 187         if(brk->type == 0) {
 188                 #ifdef DEBUG
 189                 printf("clearing hw break %d\n", id);
 190                 #endif
 191
 192                 stlink_write_mem32(sl, 0xe0002008 + id * 4, 4);
 193         } else {
 194                 sl->q_buf[0] = ( brk->addr        & 0xff) | 1;
 195                 sl->q_buf[1] = ((brk->addr >> 8)  & 0xff);
 196                 sl->q_buf[2] = ((brk->addr >> 16) & 0xff);
 197                 sl->q_buf[3] = ((brk->addr >> 24) & 0xff) | (brk->type << 6);
 198
 199                 #ifdef DEBUG
 200                 printf("setting hw break %d at %08x (%d)\n",
 201                         id, brk->addr, brk->type);
 202                 printf("reg %02x %02x %02x %02x\n",
 203                         sl->q_buf[3], sl->q_buf[2], sl->q_buf[1], sl->q_buf[0]);
 204                 #endif
 205
 206                 stlink_write_mem32(sl, 0xe0002008 + id * 4, 4);
 207         }
 208
 209         return 0;
 210 }
 211
 212 #define FLASH_BASE 0x08000000
 213 #define FLASH_PAGE 0x400
 214 #define FLASH_PAGE_MASK (~((1 << 10) - 1))
 215 #define FLASH_SIZE (FLASH_PAGE * 128)
 216
 217 struct flash_block {
 218         stm32_addr_t addr;
 219         unsigned     length;
 220         uint8_t*     data;
 221
 222         struct flash_block* next;
 223 };
 224
 225 static struct flash_block* flash_root;
 226
 227 static int flash_add_block(stm32_addr_t addr, unsigned length) {
 228         if(addr < FLASH_BASE || addr + length > FLASH_BASE + FLASH_SIZE) {
 229                 fprintf(stderr, "flash_add_block: incorrect bounds\n");
 230                 return -1;
 231         }
 232
 233         if(addr % FLASH_PAGE != 0 || length % FLASH_PAGE != 0) {
 234                 fprintf(stderr, "flash_add_block: unaligned block\n");
 235                 return -1;
 236         }
 237
 238         struct flash_block* new = malloc(sizeof(struct flash_block));
 239         new->next = flash_root;
 240
 241         new->addr   = addr;
 242         new->length = length;
 243         new->data   = calloc(length, 1);
 244
 245         flash_root = new;
 246
 247         return 0;
 248 }
 249
 250 static int flash_populate(stm32_addr_t addr, uint8_t* data, unsigned length) {
 251         int fit_blocks = 0, fit_length = 0;
 252
 253         for(struct flash_block* fb = flash_root; fb; fb = fb->next) {
 254                 /* Block: ------X------Y--------
 255                  * Data:            a-----b
 256                  *                a--b
 257                  *            a-----------b
 258                  * Block intersects with data, if:
 259                  *  a < Y && b > x
 260                  */
 261
 262                 unsigned X = fb->addr, Y = fb->addr + fb->length;
 263                 unsigned a = addr, b = addr + length;
 264                 if(a < Y && b > X) {
 265                         // from start of the block
 266                         unsigned start = (a > X ? a : X) - X;
 267                         unsigned end   = (b > Y ? Y : b) - X;
 268
 269                         memcpy(fb->data + start, data, end - start);
 270
 271                         fit_blocks++;
 272                         fit_length += end - start;
 273                 }
 274         }
 275
 276         if(fit_blocks == 0) {
 277                 fprintf(stderr, "Unfit data block %08x -> %04x\n", addr, length);
 278                 return -1;
 279         }
 280
 281         if(fit_length != length) {
 282                 fprintf(stderr, "warning: data block %08x -> %04x truncated to %04x\n",
 283                         addr, length, fit_length);
 284                 fprintf(stderr, "(this is not an error, just a GDB glitch)\n");
 285         }
 286
 287         return 0;
 288 }
 289
 290 static int flash_go(struct stlink* sl) {
 291         int error = -1;
 292
 293         // Some kinds of clock settings do not allow writing to flash.
 294         stlink_reset(sl);
 295
 296         for(struct flash_block* fb = flash_root; fb; fb = fb->next) {
 297                 #ifdef DEBUG
 298                 printf("flash_do: block %08x -> %04x\n", fb->addr, fb->length);
 299                 #endif
 300
 301                 unsigned length = fb->length;
 302                 for(stm32_addr_t page = fb->addr; page < fb->addr + fb->length; page += 0x400) {
 303                         #ifdef DEBUG
 304                         printf("flash_do: page %08x\n", page);
 305                         #endif
 306
 307                         stlink_erase_flash_page(sl, page);
 308
 309                         if(stlink_write_flash(sl, page, fb->data + (page - fb->addr),
 310                                         length > 0x400 ? 0x400 : length) < 0)
 311                                 goto error;
 312                 }
 313
 314         }
 315
 316         stlink_reset(sl);
 317
 318         error = 0;
 319
 320 error:
 321         for(struct flash_block* fb = flash_root, *next; fb; fb = next) {
 322                 next = fb->next;
 323                 free(fb->data);
 324                 free(fb);
 325         }
 326
 327         flash_root = NULL;
 328
 329         return error;
 330 }
 331
 332 int serve(struct stlink* sl, int port) {
 333         int sock = socket(AF_INET, SOCK_STREAM, 0);
 334         if(sock < 0) {
 335                 perror("socket");
 336                 return 1;
 337         }
 338
 339         unsigned int val = 1;
 340         setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
 341
 342         struct sockaddr_in serv_addr = {0};
 343         serv_addr.sin_family = AF_INET;
 344         serv_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
 345         serv_addr.sin_port = htons(port);
 346
 347         if(bind(sock, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0) {
 348                 perror("bind");
 349                 return 1;
 350         }
 351
 352         if(listen(sock, 5) < 0) {
 353                 perror("listen");
 354                 return 1;
 355         }
 356
 357         stlink_force_debug(sl);
 358         stlink_reset(sl);
 359         init_code_breakpoints(sl);
 360
 361         printf("Listening at *:%d...\n", port);
 362
 363         int client = accept(sock, NULL, NULL);
 364         if(client < 0) {
 365                 perror("accept");
 366                 return 1;
 367         }
 368
 369         close(sock);
 370
 371         printf("GDB connected.\n");
 372
 373         /*
 374          * To allow resetting the chip from GDB it is required to
 375          * emulate attaching and detaching to target.
 376          */
 377         unsigned int attached = 1;
 378
 379         while(1) {
 380                 char* packet;
 381
 382                 int status = gdb_recv_packet(client, &packet);
 383                 if(status < 0) {
 384                         fprintf(stderr, "cannot recv: %d\n", status);
 385                         return 1;
 386                 }
 387
 388                 #ifdef DEBUG
 389                 printf("recv: %s\n", packet);
 390                 #endif
 391
 392                 char* reply = NULL;
 393
 394                 switch(packet[0]) {
 395                 case 'q': {
 396                         if(packet[1] == 'P' || packet[1] == 'C' || packet[1] == 'L') {
 397                                 reply = strdup("");
 398                                 break;
 399                         }
 400
 401                         char *separator = strstr(packet, ":"), *params = "";
 402                         if(separator == NULL) {
 403                                 separator = packet + strlen(packet);
 404                         } else {
 405                                 params = separator + 1;
 406                         }
 407
 408                         unsigned queryNameLength = (separator - &packet[1]);
 409                         char* queryName = calloc(queryNameLength + 1, 1);
 410                         strncpy(queryName, &packet[1], queryNameLength);
 411
 412                         #ifdef DEBUG
 413                         printf("query: %s;%s\n", queryName, params);
 414                         #endif
 415
 416                         if(!strcmp(queryName, "Supported")) {
 417                                 reply = strdup("PacketSize=3fff;qXfer:memory-map:read+");
 418                         } else if(!strcmp(queryName, "Xfer")) {
 419                                 char *type, *op, *annex, *s_addr, *s_length;
 420                                 char *tok = params;
 421
 422                                 type     = strsep(&tok, ":");
 423                                 op       = strsep(&tok, ":");
 424                                 annex    = strsep(&tok, ":");
 425                                 s_addr   = strsep(&tok, ",");
 426                                 s_length = tok;
 427
 428                                 unsigned addr = strtoul(s_addr, NULL, 16),
 429                                        length = strtoul(s_length, NULL, 16);
 430
 431                                 #ifdef DEBUG
 432                                 printf("Xfer: type:%s;op:%s;annex:%s;addr:%d;length:%d\n",
 433                                         type, op, annex, addr, length);
 434                                 #endif
 435
 436                                 const char* data = NULL;
 437
 438                                 if(!strcmp(type, "memory-map") && !strcmp(op, "read"))
 439                                         data = current_memory_map;
 440
 441                                 if(data) {
 442                                         unsigned data_length = strlen(data);
 443                                         if(addr + length > data_length)
 444                                                 length = data_length - addr;
 445
 446                                         if(length == 0) {
 447                                                 reply = strdup("l");
 448                                         } else {
 449                                                 reply = calloc(length + 2, 1);
 450                                                 reply[0] = 'm';
 451                                                 strncpy(&reply[1], data, length);
 452                                         }
 453                                 }
 454                         }
 455
 456                         if(reply == NULL)
 457                                 reply = strdup("");
 458
 459                         free(queryName);
 460
 461                         break;
 462                 }
 463
 464                 case 'v': {
 465                         char *params = NULL;
 466                         char *cmdName = strtok_r(packet, ":;", &params);
 467
 468                         cmdName++; // vCommand -> Command
 469
 470                         if(!strcmp(cmdName, "FlashErase")) {
 471                                 char *s_addr, *s_length;
 472                                 char *tok = params;
 473
 474                                 s_addr   = strsep(&tok, ",");
 475                                 s_length = tok;
 476
 477                                 unsigned addr = strtoul(s_addr, NULL, 16),
 478                                        length = strtoul(s_length, NULL, 16);
 479
 480                                 #ifdef DEBUG
 481                                 printf("FlashErase: addr:%08x,len:%04x\n",
 482                                         addr, length);
 483                                 #endif
 484
 485                                 if(flash_add_block(addr, length) < 0) {
 486                                         reply = strdup("E00");
 487                                 } else {
 488                                         reply = strdup("OK");
 489                                 }
 490                         } else if(!strcmp(cmdName, "FlashWrite")) {
 491                                 char *s_addr, *data;
 492                                 char *tok = params;
 493
 494                                 s_addr = strsep(&tok, ":");
 495                                 data   = tok;
 496
 497                                 unsigned addr = strtoul(s_addr, NULL, 16);
 498                                 unsigned data_length = status - (data - packet);
 499
 500                                 // Length of decoded data cannot be more than
 501                                 // encoded, as escapes are removed.
 502                                 // Additional byte is reserved for alignment fix.
 503                                 uint8_t *decoded = calloc(data_length + 1, 1);
 504                                 unsigned dec_index = 0;
 505                                 for(int i = 0; i < data_length; i++) {
 506                                         if(data[i] == 0x7d) {
 507                                                 i++;
 508                                                 decoded[dec_index++] = data[i] ^ 0x20;
 509                                         } else {
 510                                                 decoded[dec_index++] = data[i];
 511                                         }
 512                                 }
 513
 514                                 // Fix alignment
 515                                 if(dec_index % 2 != 0)
 516                                         dec_index++;
 517
 518                                 #ifdef DEBUG
 519                                 printf("binary packet %d -> %d\n", data_length, dec_index);
 520                                 #endif
 521
 522                                 if(flash_populate(addr, decoded, dec_index) < 0) {
 523                                         reply = strdup("E00");
 524                                 } else {
 525                                         reply = strdup("OK");
 526                                 }
 527                         } else if(!strcmp(cmdName, "FlashDone")) {
 528                                 if(flash_go(sl) < 0) {
 529                                         reply = strdup("E00");
 530                                 } else {
 531                                         reply = strdup("OK");
 532                                 }
 533                         } else if(!strcmp(cmdName, "Kill")) {
 534                                 attached = 0;
 535
 536                                 reply = strdup("OK");
 537                         }
 538
 539                         if(reply == NULL)
 540                                 reply = strdup("");
 541
 542                         break;
 543                 }
 544
 545                 case 'c':
 546                         stlink_run(sl);
 547
 548                         while(1) {
 549                                 int status = gdb_check_for_interrupt(client);
 550                                 if(status < 0) {
 551                                         fprintf(stderr, "cannot check for int: %d\n", status);
 552                                         return 1;
 553                                 }
 554
 555                                 if(status == 1) {
 556                                         stlink_force_debug(sl);
 557                                         break;
 558                                 }
 559
 560                                 stlink_status(sl);
 561                                 if(sl->core_stat == STLINK_CORE_HALTED) {
 562                                         break;
 563                                 }
 564
 565                                 usleep(100000);
 566                         }
 567
 568                         reply = strdup("S05"); // TRAP
 569                         break;
 570
 571                 case 's':
 572                         stlink_step(sl);
 573
 574                         reply = strdup("S05"); // TRAP
 575                         break;
 576
 577                 case '?':
 578                         if(attached) {
 579                                 reply = strdup("S05"); // TRAP
 580                         } else {
 581                                 /* Stub shall reply OK if not attached. */
 582                                 reply = strdup("OK");
 583                         }
 584                         break;
 585
 586                 case 'g':
 587                         stlink_read_all_regs(sl);
 588
 589                         reply = calloc(8 * 16 + 1, 1);
 590                         for(int i = 0; i < 16; i++)
 591                                 sprintf(&reply[i * 8], "%08x", htonl(sl->reg.r[i]));
 592
 593                         break;
 594
 595                 case 'p': {
 596                         unsigned id = strtoul(&packet[1], NULL, 16), reg = 0xDEADDEAD;
 597
 598                         if(id < 16) {
 599                                 stlink_read_reg(sl, id);
 600                                 reg = htonl(sl->reg.r[id]);
 601                         } else if(id == 0x19) {
 602                                 stlink_read_reg(sl, 16);
 603                                 reg = htonl(sl->reg.xpsr);
 604                         } else {
 605                                 reply = strdup("E00");
 606                         }
 607
 608                         reply = calloc(8 + 1, 1);
 609                         sprintf(reply, "%08x", reg);
 610
 611                         break;
 612                 }
 613
 614                 case 'P': {
 615                         char* s_reg = &packet[1];
 616                         char* s_value = strstr(&packet[1], "=") + 1;
 617
 618                         unsigned reg   = strtoul(s_reg,   NULL, 16);
 619                         unsigned value = strtoul(s_value, NULL, 16);
 620
 621                         if(reg < 16) {
 622                                 stlink_write_reg(sl, ntohl(value), reg);
 623                         } else if(reg == 0x19) {
 624                                 stlink_write_reg(sl, ntohl(value), 16);
 625                         } else {
 626                                 reply = strdup("E00");
 627                         }
 628
 629                         if(!reply) {
 630                                 reply = strdup("OK");
 631                         }
 632
 633                         break;
 634                 }
 635
 636                 case 'G':
 637                         for(int i = 0; i < 16; i++) {
 638                                 char str[9] = {0};
 639                                 strncpy(str, &packet[1 + i * 8], 8);
 640                                 uint32_t reg = strtoul(str, NULL, 16);
 641                                 stlink_write_reg(sl, ntohl(reg), i);
 642                         }
 643
 644                         reply = strdup("OK");
 645                         break;
 646
 647                 case 'm': {
 648                         char* s_start = &packet[1];
 649                         char* s_count = strstr(&packet[1], ",") + 1;
 650
 651                         stm32_addr_t start = strtoul(s_start, NULL, 16);
 652                         unsigned     count = strtoul(s_count, NULL, 16);
 653
 654                         unsigned adj_start = start % 4;
 655
 656                         stlink_read_mem32(sl, start - adj_start, (count % 4 == 0) ?
 657                                                 count : count + 4 - (count % 4));
 658
 659                         reply = calloc(count * 2 + 1, 1);
 660                         for(int i = 0; i < count; i++) {
 661                                 reply[i * 2 + 0] = hex[sl->q_buf[i + adj_start] >> 4];
 662                                 reply[i * 2 + 1] = hex[sl->q_buf[i + adj_start] & 0xf];
 663                         }
 664
 665                         break;
 666                 }
 667
 668                 case 'M': {
 669                         char* s_start = &packet[1];
 670                         char* s_count = strstr(&packet[1], ",") + 1;
 671                         char* hexdata = strstr(packet, ":") + 1;
 672
 673                         stm32_addr_t start = strtoul(s_start, NULL, 16);
 674                         unsigned     count = strtoul(s_count, NULL, 16);
 675
 676                         for(int i = 0; i < count; i ++) {
 677                                 char hex[3] = { hexdata[i*2], hexdata[i*2+1], 0 };
 678                                 uint8_t byte = strtoul(hex, NULL, 16);
 679                                 sl->q_buf[i] = byte;
 680                         }
 681
 682                         if((count % 4) == 0 && (start % 4) == 0) {
 683                                 stlink_write_mem32(sl, start, count);
 684                         } else {
 685                                 stlink_write_mem8(sl, start, count);
 686                         }
 687
 688                         reply = strdup("OK");
 689
 690                         break;
 691                 }
 692
 693                 case 'Z': {
 694                         if(packet[1] == '1') {
 695                                 stm32_addr_t addr = strtoul(&packet[3], NULL, 16);
 696                                 if(update_code_breakpoint(sl, addr, 1) < 0) {
 697                                         reply = strdup("E00");
 698                                 } else {
 699                                         reply = strdup("OK");
 700                                 }
 701                         } else {
 702                                 reply = strdup("");
 703                         }
 704
 705                         break;
 706                 }
 707
 708                 case 'z': {
 709                         if(packet[1] == '1') {
 710                                 stm32_addr_t addr = strtoul(&packet[3], NULL, 16);
 711                                 update_code_breakpoint(sl, addr, 0);
 712
 713                                 reply = strdup("OK");
 714                         } else {
 715                                 reply = strdup("");
 716                         }
 717
 718                         break;
 719                 }
 720
 721                 case '!': {
 722                         /*
 723                          * Enter extended mode which allows restarting.
 724                          * We do support that always.
 725                          */
 726
 727                         reply = strdup("OK");
 728
 729                         break;
 730                 }
 731
 732                 case 'R': {
 733                         /* Reset the core. */
 734
 735                         stlink_reset(sl);
 736                         init_code_breakpoints(sl);
 737
 738                         attached = 1;
 739
 740                         reply = strdup("OK");
 741
 742                         break;
 743                 }
 744
 745                 default:
 746                         reply = strdup("");
 747                 }
 748
 749                 if(reply) {
 750                         #ifdef DEBUG
 751                         printf("send: %s\n", reply);
 752                         #endif
 753
 754                         int result = gdb_send_packet(client, reply);
 755                         if(result != 0) {
 756                                 fprintf(stderr, "cannot send: %d\n", result);
 757                                 return 1;
 758                         }
 759
 760                         free(reply);
 761                 }
 762
 763                 free(packet);
 764         }
 765
 766         return 0;
 767 }