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_base, flash_size, flash_pagesize;
  28         uint32_t bootrom_base, bootrom_size;
  29         uint32_t sram_base, sram_size;
  30 } const devices[] = {
  31         { 0x10016420, "STM32F100 on Discovery",
  32           0x08000000, 128  * 1024, 1024,
  33           0x1ffff000, 2    * 1024,
  34           0x20000000, 8    * 1024},
  35         { 0x10016412, "Low-density device",
  36           0x08000000, 32   * 1024, 1024,
  37           0x1ffff000, 2    * 1024,
  38           0x20000000, 4    * 1024},
  39         { 0x10016410, "Medium-density device",
  40           0x08000000, 128  * 1024, 1024,
  41           0x1ffff000, 2    * 1024,
  42           0x20000000, 8    * 1024},
  43         { 0x10016414, "High-density device",
  44           0x08000000, 512  * 1024, 1024,
  45           0x1ffff000, 2    * 1024,
  46           0x20000000, 8    * 1024},
  47         { 0x10016430, "XL-density device",
  48           0x08000000, 1024 * 1024, 2048,
  49           0x1fffe000, 6    * 1024,
  50           0x20000000, 8    * 1024},
  51         { 0x10016418, "Connectivity line device",
  52           0x08000000, 256  * 1024, 2048,
  53           0x1fffb000, 18   * 1024,
  54           0x20000000, 8    * 1024},
  55         { 0, }
  56 };
  57
  58 int serve(struct stlink* sl, int port);
  59 char* make_memory_map(const struct chip_params *params);
  60
  61 int main(int argc, char** argv) {
  62         if(argc != 3) {
  63                 fprintf(stderr, "Usage: %s <port> /dev/sgX\n", argv[0]);
  64                 return 1;
  65         }
  66
  67         struct stlink *sl = stlink_quirk_open(argv[2], 0);
  68         if (sl == NULL)
  69                 return 1;
  70
  71         if(stlink_current_mode(sl) != STLINK_DEV_DEBUG_MODE)
  72                 stlink_enter_swd_mode(sl);
  73
  74         uint32_t chip_id;
  75
  76         stlink_read_mem32(sl, 0xE0042000, 4);
  77         chip_id = sl->q_buf[0] | (sl->q_buf[1] << 8) | (sl->q_buf[2] << 16) |
  78                 (sl->q_buf[3] << 24);
  79
  80         printf("Chip ID is %08x.\n", chip_id);
  81
  82         const struct chip_params* params = NULL;
  83
  84         for(int i = 0; i < sizeof(devices) / sizeof(devices[0]); i++) {
  85                 if(devices[i].chip_id == chip_id) {
  86                         params = &devices[i];
  87                         break;
  88                 }
  89         }
  90
  91         if(params == NULL) {
  92                 fprintf(stderr, "Cannot recognize the connected device!\n");
  93                 return 0;
  94         }
  95
  96         printf("Device connected: %s\n", params->description);
  97         printf("Device parameters: SRAM @%08x: %x, Flash @%08x: %x (pages of %x bytes), Boot ROM: @%08x, %x\n",
  98                 params->sram_base, params->sram_size,
  99                 params->flash_base, params->flash_size, params->flash_pagesize,
 100                 params->bootrom_base, params->bootrom_size);
 101
 102         current_memory_map = make_memory_map(params);
 103
 104         int port = atoi(argv[1]);
 105
 106         while(serve(sl, port) == 0);
 107
 108         stlink_close(sl);
 109
 110         return 0;
 111 }
 112
 113 static const char* const memory_map_template =
 114   "<?xml version=\"1.0\"?>"
 115   "<!DOCTYPE memory-map PUBLIC \"+//IDN gnu.org//DTD GDB Memory Map V1.0//EN\""
 116   "     \"http://sourceware.org/gdb/gdb-memory-map.dtd\">"
 117   "<memory-map>"
 118   "  <memory type=\"rom\" start=\"0x00000000\" length=\"0x%x\"/>" // code = sram, bootrom or flash; flash is bigger
 119   "  <memory type=\"ram\" start=\"0x%08x\" length=\"0x%x\"/>"     // sram 8k
 120   "  <memory type=\"flash\" start=\"0x%08x\" length=\"0x%x\">"
 121   "    <property name=\"blocksize\">0x%x</property>"
 122   "  </memory>"
 123   "  <memory type=\"ram\" start=\"0x40000000\" length=\"0x1fffffff\"/>" // peripheral regs
 124   "  <memory type=\"ram\" start=\"0xe0000000\" length=\"0x1fffffff\"/>" // cortex regs
 125   "  <memory type=\"rom\" start=\"0x%08x\" length=\"0x%x\"/>"           // bootrom
 126   "</memory-map>";
 127
 128 char* make_memory_map(const struct chip_params *params) {
 129         /* This will be freed in serve() */
 130         char* map = malloc(4096);
 131         map[0] = '\0';
 132
 133         snprintf(map, 4096, memory_map_template,
 134                             params->flash_size,
 135                             params->sram_base, params->sram_size,
 136                             params->flash_base, params->flash_size, params->flash_pagesize,
 137                             params->bootrom_base, params->bootrom_size);
 138
 139         return map;
 140 }
 141
 142 #define CODE_BREAK_NUM  6
 143
 144 #define CODE_BREAK_LOW  0x01
 145 #define CODE_BREAK_HIGH 0x02
 146
 147 struct code_hw_breakpoint {
 148         stm32_addr_t addr;
 149         int          type;
 150 };
 151
 152 struct code_hw_breakpoint code_breaks[CODE_BREAK_NUM];
 153
 154 static void init_code_breakpoints(struct stlink* sl) {
 155         memset(sl->q_buf, 0, 4);
 156         sl->q_buf[0] = 0x03; // KEY | ENABLE
 157         stlink_write_mem32(sl, 0xe0002000, 4);
 158
 159         memset(sl->q_buf, 0, 4);
 160         for(int i = 0; i < CODE_BREAK_NUM; i++) {
 161                 code_breaks[i].type = 0;
 162                 stlink_write_mem32(sl, 0xe0002008 + i * 4, 4);
 163         }
 164 }
 165
 166 static int update_code_breakpoint(struct stlink* sl, stm32_addr_t addr, int set) {
 167         stm32_addr_t fpb_addr = addr & ~0x3;
 168         int type = addr & 0x2 ? CODE_BREAK_HIGH : CODE_BREAK_LOW;
 169
 170         if(addr & 1) {
 171                 fprintf(stderr, "update_code_breakpoint: unaligned address %08x\n", addr);
 172                 return -1;
 173         }
 174
 175         int id = -1;
 176         for(int i = 0; i < CODE_BREAK_NUM; i++) {
 177                 if(fpb_addr == code_breaks[i].addr ||
 178                         (set && code_breaks[i].type == 0)) {
 179                         id = i;
 180                         break;
 181                 }
 182         }
 183
 184         if(id == -1) {
 185                 if(set) return -1; // Free slot not found
 186                 else    return 0;  // Breakpoint is already removed
 187         }
 188
 189         struct code_hw_breakpoint* brk = &code_breaks[id];
 190
 191         brk->addr = fpb_addr;
 192
 193         if(set) brk->type |= type;
 194         else    brk->type &= ~type;
 195
 196         memset(sl->q_buf, 0, 4);
 197
 198         if(brk->type == 0) {
 199                 #ifdef DEBUG
 200                 printf("clearing hw break %d\n", id);
 201                 #endif
 202
 203                 stlink_write_mem32(sl, 0xe0002008 + id * 4, 4);
 204         } else {
 205                 sl->q_buf[0] = ( brk->addr        & 0xff) | 1;
 206                 sl->q_buf[1] = ((brk->addr >> 8)  & 0xff);
 207                 sl->q_buf[2] = ((brk->addr >> 16) & 0xff);
 208                 sl->q_buf[3] = ((brk->addr >> 24) & 0xff) | (brk->type << 6);
 209
 210                 #ifdef DEBUG
 211                 printf("setting hw break %d at %08x (%d)\n",
 212                         id, brk->addr, brk->type);
 213                 printf("reg %02x %02x %02x %02x\n",
 214                         sl->q_buf[3], sl->q_buf[2], sl->q_buf[1], sl->q_buf[0]);
 215                 #endif
 216
 217                 stlink_write_mem32(sl, 0xe0002008 + id * 4, 4);
 218         }
 219
 220         return 0;
 221 }
 222
 223 #define FLASH_BASE 0x08000000
 224 #define FLASH_PAGE 0x400
 225 #define FLASH_PAGE_MASK (~((1 << 10) - 1))
 226 #define FLASH_SIZE (FLASH_PAGE * 128)
 227
 228 struct flash_block {
 229         stm32_addr_t addr;
 230         unsigned     length;
 231         uint8_t*     data;
 232
 233         struct flash_block* next;
 234 };
 235
 236 static struct flash_block* flash_root;
 237
 238 static int flash_add_block(stm32_addr_t addr, unsigned length) {
 239         if(addr < FLASH_BASE || addr + length > FLASH_BASE + FLASH_SIZE) {
 240                 fprintf(stderr, "flash_add_block: incorrect bounds\n");
 241                 return -1;
 242         }
 243
 244         if(addr % FLASH_PAGE != 0 || length % FLASH_PAGE != 0) {
 245                 fprintf(stderr, "flash_add_block: unaligned block\n");
 246                 return -1;
 247         }
 248
 249         struct flash_block* new = malloc(sizeof(struct flash_block));
 250         new->next = flash_root;
 251
 252         new->addr   = addr;
 253         new->length = length;
 254         new->data   = calloc(length, 1);
 255
 256         flash_root = new;
 257
 258         return 0;
 259 }
 260
 261 static int flash_populate(stm32_addr_t addr, uint8_t* data, unsigned length) {
 262         int fit_blocks = 0, fit_length = 0;
 263
 264         for(struct flash_block* fb = flash_root; fb; fb = fb->next) {
 265                 /* Block: ------X------Y--------
 266                  * Data:            a-----b
 267                  *                a--b
 268                  *            a-----------b
 269                  * Block intersects with data, if:
 270                  *  a < Y && b > x
 271                  */
 272
 273                 unsigned X = fb->addr, Y = fb->addr + fb->length;
 274                 unsigned a = addr, b = addr + length;
 275                 if(a < Y && b > X) {
 276                         // from start of the block
 277                         unsigned start = (a > X ? a : X) - X;
 278                         unsigned end   = (b > Y ? Y : b) - X;
 279
 280                         memcpy(fb->data + start, data, end - start);
 281
 282                         fit_blocks++;
 283                         fit_length += end - start;
 284                 }
 285         }
 286
 287         if(fit_blocks == 0) {
 288                 fprintf(stderr, "Unfit data block %08x -> %04x\n", addr, length);
 289                 return -1;
 290         }
 291
 292         if(fit_length != length) {
 293                 fprintf(stderr, "warning: data block %08x -> %04x truncated to %04x\n",
 294                         addr, length, fit_length);
 295                 fprintf(stderr, "(this is not an error, just a GDB glitch)\n");
 296         }
 297
 298         return 0;
 299 }
 300
 301 static int flash_go(struct stlink* sl) {
 302         int error = -1;
 303
 304         // Some kinds of clock settings do not allow writing to flash.
 305         stlink_reset(sl);
 306
 307         for(struct flash_block* fb = flash_root; fb; fb = fb->next) {
 308                 #ifdef DEBUG
 309                 printf("flash_do: block %08x -> %04x\n", fb->addr, fb->length);
 310                 #endif
 311
 312                 unsigned length = fb->length;
 313                 for(stm32_addr_t page = fb->addr; page < fb->addr + fb->length; page += 0x400) {
 314                         #ifdef DEBUG
 315                         printf("flash_do: page %08x\n", page);
 316                         #endif
 317
 318                         stlink_erase_flash_page(sl, page);
 319
 320                         if(stlink_write_flash(sl, page, fb->data + (page - fb->addr),
 321                                         length > 0x400 ? 0x400 : length) < 0)
 322                                 goto error;
 323                 }
 324
 325         }
 326
 327         stlink_reset(sl);
 328
 329         error = 0;
 330
 331 error:
 332         for(struct flash_block* fb = flash_root, *next; fb; fb = next) {
 333                 next = fb->next;
 334                 free(fb->data);
 335                 free(fb);
 336         }
 337
 338         flash_root = NULL;
 339
 340         return error;
 341 }
 342
 343 int serve(struct stlink* sl, int port) {
 344         int sock = socket(AF_INET, SOCK_STREAM, 0);
 345         if(sock < 0) {
 346                 perror("socket");
 347                 return 1;
 348         }
 349
 350         unsigned int val = 1;
 351         setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
 352
 353         struct sockaddr_in serv_addr = {0};
 354         serv_addr.sin_family = AF_INET;
 355         serv_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
 356         serv_addr.sin_port = htons(port);
 357
 358         if(bind(sock, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0) {
 359                 perror("bind");
 360                 return 1;
 361         }
 362
 363         if(listen(sock, 5) < 0) {
 364                 perror("listen");
 365                 return 1;
 366         }
 367
 368         stlink_force_debug(sl);
 369         stlink_reset(sl);
 370         init_code_breakpoints(sl);
 371
 372         printf("Listening at *:%d...\n", port);
 373
 374         int client = accept(sock, NULL, NULL);
 375         if(client < 0) {
 376                 perror("accept");
 377                 return 1;
 378         }
 379
 380         close(sock);
 381
 382         printf("GDB connected.\n");
 383
 384         /*
 385          * To allow resetting the chip from GDB it is required to
 386          * emulate attaching and detaching to target.
 387          */
 388         unsigned int attached = 1;
 389
 390         while(1) {
 391                 char* packet;
 392
 393                 int status = gdb_recv_packet(client, &packet);
 394                 if(status < 0) {
 395                         fprintf(stderr, "cannot recv: %d\n", status);
 396                         return 1;
 397                 }
 398
 399                 #ifdef DEBUG
 400                 printf("recv: %s\n", packet);
 401                 #endif
 402
 403                 char* reply = NULL;
 404
 405                 switch(packet[0]) {
 406                 case 'q': {
 407                         if(packet[1] == 'P' || packet[1] == 'C' || packet[1] == 'L') {
 408                                 reply = strdup("");
 409                                 break;
 410                         }
 411
 412                         char *separator = strstr(packet, ":"), *params = "";
 413                         if(separator == NULL) {
 414                                 separator = packet + strlen(packet);
 415                         } else {
 416                                 params = separator + 1;
 417                         }
 418
 419                         unsigned queryNameLength = (separator - &packet[1]);
 420                         char* queryName = calloc(queryNameLength + 1, 1);
 421                         strncpy(queryName, &packet[1], queryNameLength);
 422
 423                         #ifdef DEBUG
 424                         printf("query: %s;%s\n", queryName, params);
 425                         #endif
 426
 427                         if(!strcmp(queryName, "Supported")) {
 428                                 reply = strdup("PacketSize=3fff;qXfer:memory-map:read+");
 429                         } else if(!strcmp(queryName, "Xfer")) {
 430                                 char *type, *op, *annex, *s_addr, *s_length;
 431                                 char *tok = params;
 432
 433                                 type     = strsep(&tok, ":");
 434                                 op       = strsep(&tok, ":");
 435                                 annex    = strsep(&tok, ":");
 436                                 s_addr   = strsep(&tok, ",");
 437                                 s_length = tok;
 438
 439                                 unsigned addr = strtoul(s_addr, NULL, 16),
 440                                        length = strtoul(s_length, NULL, 16);
 441
 442                                 #ifdef DEBUG
 443                                 printf("Xfer: type:%s;op:%s;annex:%s;addr:%d;length:%d\n",
 444                                         type, op, annex, addr, length);
 445                                 #endif
 446
 447                                 const char* data = NULL;
 448
 449                                 if(!strcmp(type, "memory-map") && !strcmp(op, "read"))
 450                                         data = current_memory_map;
 451
 452                                 if(data) {
 453                                         unsigned data_length = strlen(data);
 454                                         if(addr + length > data_length)
 455                                                 length = data_length - addr;
 456
 457                                         if(length == 0) {
 458                                                 reply = strdup("l");
 459                                         } else {
 460                                                 reply = calloc(length + 2, 1);
 461                                                 reply[0] = 'm';
 462                                                 strncpy(&reply[1], data, length);
 463                                         }
 464                                 }
 465                         }
 466
 467                         if(reply == NULL)
 468                                 reply = strdup("");
 469
 470                         free(queryName);
 471
 472                         break;
 473                 }
 474
 475                 case 'v': {
 476                         char *params = NULL;
 477                         char *cmdName = strtok_r(packet, ":;", &params);
 478
 479                         cmdName++; // vCommand -> Command
 480
 481                         if(!strcmp(cmdName, "FlashErase")) {
 482                                 char *s_addr, *s_length;
 483                                 char *tok = params;
 484
 485                                 s_addr   = strsep(&tok, ",");
 486                                 s_length = tok;
 487
 488                                 unsigned addr = strtoul(s_addr, NULL, 16),
 489                                        length = strtoul(s_length, NULL, 16);
 490
 491                                 #ifdef DEBUG
 492                                 printf("FlashErase: addr:%08x,len:%04x\n",
 493                                         addr, length);
 494                                 #endif
 495
 496                                 if(flash_add_block(addr, length) < 0) {
 497                                         reply = strdup("E00");
 498                                 } else {
 499                                         reply = strdup("OK");
 500                                 }
 501                         } else if(!strcmp(cmdName, "FlashWrite")) {
 502                                 char *s_addr, *data;
 503                                 char *tok = params;
 504
 505                                 s_addr = strsep(&tok, ":");
 506                                 data   = tok;
 507
 508                                 unsigned addr = strtoul(s_addr, NULL, 16);
 509                                 unsigned data_length = status - (data - packet);
 510
 511                                 // Length of decoded data cannot be more than
 512                                 // encoded, as escapes are removed.
 513                                 // Additional byte is reserved for alignment fix.
 514                                 uint8_t *decoded = calloc(data_length + 1, 1);
 515                                 unsigned dec_index = 0;
 516                                 for(int i = 0; i < data_length; i++) {
 517                                         if(data[i] == 0x7d) {
 518                                                 i++;
 519                                                 decoded[dec_index++] = data[i] ^ 0x20;
 520                                         } else {
 521                                                 decoded[dec_index++] = data[i];
 522                                         }
 523                                 }
 524
 525                                 // Fix alignment
 526                                 if(dec_index % 2 != 0)
 527                                         dec_index++;
 528
 529                                 #ifdef DEBUG
 530                                 printf("binary packet %d -> %d\n", data_length, dec_index);
 531                                 #endif
 532
 533                                 if(flash_populate(addr, decoded, dec_index) < 0) {
 534                                         reply = strdup("E00");
 535                                 } else {
 536                                         reply = strdup("OK");
 537                                 }
 538                         } else if(!strcmp(cmdName, "FlashDone")) {
 539                                 if(flash_go(sl) < 0) {
 540                                         reply = strdup("E00");
 541                                 } else {
 542                                         reply = strdup("OK");
 543                                 }
 544                         } else if(!strcmp(cmdName, "Kill")) {
 545                                 attached = 0;
 546
 547                                 reply = strdup("OK");
 548                         }
 549
 550                         if(reply == NULL)
 551                                 reply = strdup("");
 552
 553                         break;
 554                 }
 555
 556                 case 'c':
 557                         stlink_run(sl);
 558
 559                         while(1) {
 560                                 int status = gdb_check_for_interrupt(client);
 561                                 if(status < 0) {
 562                                         fprintf(stderr, "cannot check for int: %d\n", status);
 563                                         return 1;
 564                                 }
 565
 566                                 if(status == 1) {
 567                                         stlink_force_debug(sl);
 568                                         break;
 569                                 }
 570
 571                                 stlink_status(sl);
 572                                 if(sl->core_stat == STLINK_CORE_HALTED) {
 573                                         break;
 574                                 }
 575
 576                                 usleep(100000);
 577                         }
 578
 579                         reply = strdup("S05"); // TRAP
 580                         break;
 581
 582                 case 's':
 583                         stlink_step(sl);
 584
 585                         reply = strdup("S05"); // TRAP
 586                         break;
 587
 588                 case '?':
 589                         if(attached) {
 590                                 reply = strdup("S05"); // TRAP
 591                         } else {
 592                                 /* Stub shall reply OK if not attached. */
 593                                 reply = strdup("OK");
 594                         }
 595                         break;
 596
 597                 case 'g':
 598                         stlink_read_all_regs(sl);
 599
 600                         reply = calloc(8 * 16 + 1, 1);
 601                         for(int i = 0; i < 16; i++)
 602                                 sprintf(&reply[i * 8], "%08x", htonl(sl->reg.r[i]));
 603
 604                         break;
 605
 606                 case 'p': {
 607                         unsigned id = strtoul(&packet[1], NULL, 16), reg = 0xDEADDEAD;
 608
 609                         if(id < 16) {
 610                                 stlink_read_reg(sl, id);
 611                                 reg = htonl(sl->reg.r[id]);
 612                         } else if(id == 0x19) {
 613                                 stlink_read_reg(sl, 16);
 614                                 reg = htonl(sl->reg.xpsr);
 615                         } else {
 616                                 reply = strdup("E00");
 617                         }
 618
 619                         reply = calloc(8 + 1, 1);
 620                         sprintf(reply, "%08x", reg);
 621
 622                         break;
 623                 }
 624
 625                 case 'P': {
 626                         char* s_reg = &packet[1];
 627                         char* s_value = strstr(&packet[1], "=") + 1;
 628
 629                         unsigned reg   = strtoul(s_reg,   NULL, 16);
 630                         unsigned value = strtoul(s_value, NULL, 16);
 631
 632                         if(reg < 16) {
 633                                 stlink_write_reg(sl, ntohl(value), reg);
 634                         } else if(reg == 0x19) {
 635                                 stlink_write_reg(sl, ntohl(value), 16);
 636                         } else {
 637                                 reply = strdup("E00");
 638                         }
 639
 640                         if(!reply) {
 641                                 reply = strdup("OK");
 642                         }
 643
 644                         break;
 645                 }
 646
 647                 case 'G':
 648                         for(int i = 0; i < 16; i++) {
 649                                 char str[9] = {0};
 650                                 strncpy(str, &packet[1 + i * 8], 8);
 651                                 uint32_t reg = strtoul(str, NULL, 16);
 652                                 stlink_write_reg(sl, ntohl(reg), i);
 653                         }
 654
 655                         reply = strdup("OK");
 656                         break;
 657
 658                 case 'm': {
 659                         char* s_start = &packet[1];
 660                         char* s_count = strstr(&packet[1], ",") + 1;
 661
 662                         stm32_addr_t start = strtoul(s_start, NULL, 16);
 663                         unsigned     count = strtoul(s_count, NULL, 16);
 664
 665                         unsigned adj_start = start % 4;
 666
 667                         stlink_read_mem32(sl, start - adj_start, (count % 4 == 0) ?
 668                                                 count : count + 4 - (count % 4));
 669
 670                         reply = calloc(count * 2 + 1, 1);
 671                         for(int i = 0; i < count; i++) {
 672                                 reply[i * 2 + 0] = hex[sl->q_buf[i + adj_start] >> 4];
 673                                 reply[i * 2 + 1] = hex[sl->q_buf[i + adj_start] & 0xf];
 674                         }
 675
 676                         break;
 677                 }
 678
 679                 case 'M': {
 680                         char* s_start = &packet[1];
 681                         char* s_count = strstr(&packet[1], ",") + 1;
 682                         char* hexdata = strstr(packet, ":") + 1;
 683
 684                         stm32_addr_t start = strtoul(s_start, NULL, 16);
 685                         unsigned     count = strtoul(s_count, NULL, 16);
 686
 687                         for(int i = 0; i < count; i ++) {
 688                                 char hex[3] = { hexdata[i*2], hexdata[i*2+1], 0 };
 689                                 uint8_t byte = strtoul(hex, NULL, 16);
 690                                 sl->q_buf[i] = byte;
 691                         }
 692
 693                         if((count % 4) == 0 && (start % 4) == 0) {
 694                                 stlink_write_mem32(sl, start, count);
 695                         } else {
 696                                 stlink_write_mem8(sl, start, count);
 697                         }
 698
 699                         reply = strdup("OK");
 700
 701                         break;
 702                 }
 703
 704                 case 'Z': {
 705                         if(packet[1] == '1') {
 706                                 stm32_addr_t addr = strtoul(&packet[3], NULL, 16);
 707                                 if(update_code_breakpoint(sl, addr, 1) < 0) {
 708                                         reply = strdup("E00");
 709                                 } else {
 710                                         reply = strdup("OK");
 711                                 }
 712                         } else {
 713                                 reply = strdup("");
 714                         }
 715
 716                         break;
 717                 }
 718
 719                 case 'z': {
 720                         if(packet[1] == '1') {
 721                                 stm32_addr_t addr = strtoul(&packet[3], NULL, 16);
 722                                 update_code_breakpoint(sl, addr, 0);
 723
 724                                 reply = strdup("OK");
 725                         } else {
 726                                 reply = strdup("");
 727                         }
 728
 729                         break;
 730                 }
 731
 732                 case '!': {
 733                         /*
 734                          * Enter extended mode which allows restarting.
 735                          * We do support that always.
 736                          */
 737
 738                         reply = strdup("OK");
 739
 740                         break;
 741                 }
 742
 743                 case 'R': {
 744                         /* Reset the core. */
 745
 746                         stlink_reset(sl);
 747                         init_code_breakpoints(sl);
 748
 749                         attached = 1;
 750
 751                         reply = strdup("OK");
 752
 753                         break;
 754                 }
 755
 756                 default:
 757                         reply = strdup("");
 758                 }
 759
 760                 if(reply) {
 761                         #ifdef DEBUG
 762                         printf("send: %s\n", reply);
 763                         #endif
 764
 765                         int result = gdb_send_packet(client, reply);
 766                         if(result != 0) {
 767                                 fprintf(stderr, "cannot send: %d\n", result);
 768                                 return 1;
 769                         }
 770
 771                         free(reply);
 772                 }
 773
 774                 free(packet);
 775         }
 776
 777         return 0;
 778 }