git.gag.com Git - fw/stlink/blob - gdbserver/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 <signal.h>
  18
  19 #include <stlink-common.h>
  20
  21 #include "gdb-remote.h"
  22
  23 #define FLASH_BASE 0x08000000
  24 #define FLASH_PAGE (sl->flash_pgsz)
  25 #define FLASH_PAGE_MASK (~((1 << 10) - 1))
  26 #define FLASH_SIZE (FLASH_PAGE * 128)
  27
  28 volatile int do_exit = 0;
  29 void ctrl_c(int sig)
  30 {
  31   do_exit = 1;
  32 }
  33
  34 static const char hex[] = "0123456789abcdef";
  35
  36 static const char* current_memory_map = NULL;
  37
  38 /*
  39  * Chip IDs are explained in the appropriate programming manual for the
  40  * DBGMCU_IDCODE register (0xE0042000)
  41  */
  42
  43 #define CORE_M3_R1 0x1BA00477
  44 #define CORE_M3_R2 0x4BA00477
  45 #define CORE_M4_R0 0x2BA01477
  46
  47 struct chip_params {
  48         uint32_t chip_id;
  49         char* description;
  50         uint32_t flash_size_reg;
  51         uint32_t max_flash_size, flash_pagesize;
  52         uint32_t sram_size;
  53         uint32_t bootrom_base, bootrom_size;
  54 } const devices[] = {
  55         { 0x410, "F1 Medium-density device", 0x1ffff7e0,
  56           0x20000,  0x400, 0x5000,  0x1ffff000, 0x800  }, // table 2, pm0063
  57         { 0x411, "F2 device", 0, /* No flash size register found in the docs*/
  58           0x100000,   0x20000, 0x20000, 0x1fff0000, 0x7800  }, // table 1, pm0059
  59         { 0x412, "F1 Low-density device", 0x1ffff7e0,
  60           0x8000,   0x400, 0x2800,  0x1ffff000, 0x800  }, // table 1, pm0063
  61         { 0x413, "F4 device", 0x1FFF7A10,
  62           0x100000,   0x20000, 0x30000,  0x1fff0000, 0x7800  }, // table 1, pm0081
  63         { 0x414, "F1 High-density device", 0x1ffff7e0,
  64           0x80000,  0x800, 0x10000, 0x1ffff000, 0x800  },  // table 3 pm0063
  65           // This ignores the EEPROM! (and uses the page erase size,
  66           // not the sector write protection...)
  67         { 0x416, "L1 Med-density device", 0x1FF8004C, // table 1, pm0062
  68           0x20000, 0x100, 0x4000, 0x1ff00000, 0x1000 },
  69         { 0x418, "F1 Connectivity line device", 0x1ffff7e0,
  70           0x40000,  0x800, 0x10000, 0x1fffb000, 0x4800 },
  71         { 0x420, "F1 Medium-density value line device", 0x1ffff7e0,
  72           0x20000,  0x400, 0x2000,  0x1ffff000, 0x800  },
  73         { 0x428, "F1 High-density value line device", 0x1ffff7e0,
  74           0x80000,  0x800, 0x8000,  0x1ffff000, 0x800  },
  75         { 0x430, "F1 XL-density device", 0x1ffff7e0,  // pm0068
  76           0x100000, 0x800, 0x18000, 0x1fffe000, 0x1800 },
  77         { 0 }
  78 };
  79
  80 int serve(stlink_t *sl, int port);
  81 char* make_memory_map(const struct chip_params *params, uint32_t flash_size);
  82
  83 int main(int argc, char** argv) {
  84
  85         stlink_t *sl = NULL;
  86
  87         const char * HelpStr =  "Usage:\n"
  88                                                                 "\t st-util port [/dev/sgX]\n"
  89                                                                 "\t st-util [port]\n"
  90                                                                 "\t st-util --help\n";
  91
  92         switch(argc) {
  93
  94                 default: {
  95                         fprintf(stderr, HelpStr, NULL);
  96                         return 1;
  97                 }
  98
  99                 case 3 : {
 100                         //sl = stlink_quirk_open(argv[2], 0);
 101                         // FIXME - hardcoded to usb....
 102                         sl = stlink_open_usb(10);
 103                         if(sl == NULL) return 1;
 104                         break;
 105                 }
 106
 107                 case 2 : {
 108                         if (strcmp(argv[1], "--help") == 0) {
 109                                 fprintf(stdout, HelpStr, NULL);
 110                                 return 1;
 111                         }
 112                 }
 113
 114                 case 1 : { // Search ST-LINK (from /dev/sg0 to /dev/sg99)
 115                         const int DevNumMax = 99;
 116                         int ExistDevCount = 0;
 117
 118                         for(int DevNum = 0; DevNum <= DevNumMax; DevNum++)
 119                         {
 120                                 if(DevNum < 10) {
 121                                         char DevName[] = "/dev/sgX";
 122                                         const int X_index = 7;
 123                                         DevName[X_index] = DevNum + '0';
 124                                         if ( !access(DevName, F_OK) ) {
 125                                                 sl = stlink_quirk_open(DevName, 0);
 126                                                 ExistDevCount++;
 127                                         }
 128                                 }
 129                                 else if(DevNum < 100) {
 130                                         char DevName[] = "/dev/sgXY";
 131                                         const int X_index = 7;
 132                                         const int Y_index = 8;
 133                                         DevName[X_index] = DevNum/10 + '0';
 134                                         DevName[Y_index] = DevNum%10 + '0';
 135                                         if ( !access(DevName, F_OK) ) {
 136                                                 sl = stlink_quirk_open(DevName, 0);
 137                                                 ExistDevCount++;
 138                                         }
 139                                 }
 140                                 if(sl != NULL) break;
 141                         }
 142
 143                         if(sl == NULL) {
 144                                 fprintf(stdout, "\nNumber of /dev/sgX devices found: %i \n",
 145                                                 ExistDevCount);
 146                                 fprintf(stderr, "ST-LINK not found\n");
 147                                 return 1;
 148                         }
 149                         break;
 150                 }
 151         }
 152
 153         if (stlink_current_mode(sl) == STLINK_DEV_DFU_MODE) {
 154             stlink_exit_dfu_mode(sl);
 155         }
 156
 157         if(stlink_current_mode(sl) != STLINK_DEV_DEBUG_MODE) {
 158           stlink_enter_swd_mode(sl);
 159         }
 160
 161         uint32_t chip_id = stlink_chip_id(sl);
 162         uint32_t core_id = stlink_core_id(sl);
 163
 164         /* Fix chip_id for F4 */
 165         if (((chip_id & 0xFFF) == 0x411) && (core_id == CORE_M4_R0)) {
 166           printf("Fixing wrong chip_id for STM32F4 Rev A errata\n");
 167           chip_id = 0x413;
 168         }
 169
 170         printf("Chip ID is %08x, Core ID is  %08x.\n", chip_id, core_id);
 171
 172         const struct chip_params* params = NULL;
 173
 174         for(int i = 0; i < sizeof(devices) / sizeof(devices[0]); i++) {
 175                 if(devices[i].chip_id == (chip_id & 0xFFF)) {
 176                         params = &devices[i];
 177                         break;
 178                 }
 179         }
 180
 181         if(params == NULL) {
 182                 fprintf(stderr, "Cannot recognize the connected device!\n");
 183                 return 0;
 184         }
 185
 186         printf("Device connected: %s\n", params->description);
 187         printf("Device parameters: SRAM: 0x%x bytes, Flash: up to 0x%x bytes in pages of 0x%x bytes\n",
 188                 params->sram_size, params->max_flash_size, params->flash_pagesize);
 189
 190         FLASH_PAGE = params->flash_pagesize;
 191
 192         uint32_t flash_size;
 193
 194         stlink_read_mem32(sl, params->flash_size_reg, 4);
 195         flash_size = sl->q_buf[0] | (sl->q_buf[1] << 8);
 196
 197         printf("Flash size is %d KiB.\n", flash_size);
 198         // memory map is in 1k blocks.
 199         current_memory_map = make_memory_map(params, flash_size * 0x400);
 200
 201         int port = 4242;
 202
 203         while(serve(sl, port) == 0);
 204
 205         /* Switch back to mass storage mode before closing. */
 206         stlink_run(sl);
 207         stlink_exit_debug_mode(sl);
 208         stlink_close(sl);
 209
 210         return 0;
 211 }
 212
 213 static const char* const memory_map_template =
 214   "<?xml version=\"1.0\"?>"
 215   "<!DOCTYPE memory-map PUBLIC \"+//IDN gnu.org//DTD GDB Memory Map V1.0//EN\""
 216   "     \"http://sourceware.org/gdb/gdb-memory-map.dtd\">"
 217   "<memory-map>"
 218   "  <memory type=\"rom\" start=\"0x00000000\" length=\"0x%x\"/>"       // code = sram, bootrom or flash; flash is bigger
 219   "  <memory type=\"ram\" start=\"0x20000000\" length=\"0x%x\"/>"       // sram 8k
 220   "  <memory type=\"flash\" start=\"0x08000000\" length=\"0x%x\">"
 221   "    <property name=\"blocksize\">0x%x</property>"
 222   "  </memory>"
 223   "  <memory type=\"ram\" start=\"0x40000000\" length=\"0x1fffffff\"/>" // peripheral regs
 224   "  <memory type=\"ram\" start=\"0xe0000000\" length=\"0x1fffffff\"/>" // cortex regs
 225   "  <memory type=\"rom\" start=\"0x%08x\" length=\"0x%x\"/>"           // bootrom
 226   "  <memory type=\"rom\" start=\"0x1ffff800\" length=\"0x8\"/>"        // option byte area
 227   "</memory-map>";
 228
 229 char* make_memory_map(const struct chip_params *params, uint32_t flash_size) {
 230         /* This will be freed in serve() */
 231         char* map = malloc(4096);
 232         map[0] = '\0';
 233
 234         snprintf(map, 4096, memory_map_template,
 235                         flash_size,
 236                         params->sram_size,
 237                         flash_size, params->flash_pagesize,
 238                         params->bootrom_base, params->bootrom_size);
 239
 240         return map;
 241 }
 242
 243
 244 /*
 245  * DWT_COMP0     0xE0001020
 246  * DWT_MASK0     0xE0001024
 247  * DWT_FUNCTION0 0xE0001028
 248  * DWT_COMP1     0xE0001030
 249  * DWT_MASK1     0xE0001034
 250  * DWT_FUNCTION1 0xE0001038
 251  * DWT_COMP2     0xE0001040
 252  * DWT_MASK2     0xE0001044
 253  * DWT_FUNCTION2 0xE0001048
 254  * DWT_COMP3     0xE0001050
 255  * DWT_MASK3     0xE0001054
 256  * DWT_FUNCTION3 0xE0001058
 257  */
 258
 259 #define DATA_WATCH_NUM 4
 260
 261 enum watchfun { WATCHDISABLED = 0, WATCHREAD = 5, WATCHWRITE = 6, WATCHACCESS = 7 };
 262
 263 struct code_hw_watchpoint {
 264         stm32_addr_t addr;
 265         uint8_t mask;
 266         enum watchfun fun;
 267 };
 268
 269 struct code_hw_watchpoint data_watches[DATA_WATCH_NUM];
 270
 271 static void init_data_watchpoints(stlink_t *sl) {
 272         #ifdef DEBUG
 273         printf("init watchpoints\n");
 274         #endif
 275
 276         // set trcena in debug command to turn on dwt unit
 277         stlink_read_mem32(sl, 0xE000EDFC, 4);
 278         sl->q_buf[3] |= 1;
 279         stlink_write_mem32(sl, 0xE000EDFC, 4);
 280
 281         // make sure all watchpoints are cleared
 282         memset(sl->q_buf, 0, 4);
 283         for(int i = 0; i < DATA_WATCH_NUM; i++) {
 284                 data_watches[i].fun = WATCHDISABLED;
 285                 stlink_write_mem32(sl, 0xe0001028 + i * 16, 4);
 286         }
 287 }
 288
 289 static int add_data_watchpoint(stlink_t *sl, enum watchfun wf, stm32_addr_t addr, unsigned int len)
 290 {
 291         int i = 0;
 292         uint32_t mask;
 293
 294         // computer mask
 295         // find a free watchpoint
 296         // configure
 297
 298         mask = -1;
 299         i = len;
 300         while(i) {
 301                 i >>= 1;
 302                 mask++;
 303         }
 304
 305         if((mask != -1) && (mask < 16)) {
 306                 for(i = 0; i < DATA_WATCH_NUM; i++) {
 307                         // is this an empty slot ?
 308                         if(data_watches[i].fun == WATCHDISABLED) {
 309                                 #ifdef DEBUG
 310                                 printf("insert watchpoint %d addr %x wf %u mask %u len %d\n", i, addr, wf, mask, len);
 311                                 #endif
 312
 313                                 data_watches[i].fun = wf;
 314                                 data_watches[i].addr = addr;
 315                                 data_watches[i].mask = mask;
 316
 317                                 // insert comparator address
 318                                 sl->q_buf[0] = (addr & 0xff);
 319                                 sl->q_buf[1] = ((addr >> 8) & 0xff);
 320                                 sl->q_buf[2] = ((addr >> 16) & 0xff);
 321                                 sl->q_buf[3] = ((addr >> 24)  & 0xff);
 322
 323                                 stlink_write_mem32(sl, 0xE0001020 + i * 16, 4);
 324
 325                                 // insert mask
 326                                 memset(sl->q_buf, 0, 4);
 327                                 sl->q_buf[0] = mask;
 328                                 stlink_write_mem32(sl, 0xE0001024 + i * 16, 4);
 329
 330                                 // insert function
 331                                 memset(sl->q_buf, 0, 4);
 332                                 sl->q_buf[0] = wf;
 333                                 stlink_write_mem32(sl, 0xE0001028 + i * 16, 4);
 334
 335                                 // just to make sure the matched bit is clear !
 336                                 stlink_read_mem32(sl,  0xE0001028 + i * 16, 4);
 337                                 return 0;
 338                         }
 339                 }
 340         }
 341
 342         #ifdef DEBUG
 343         printf("failure: add watchpoints addr %x wf %u len %u\n", addr, wf, len);
 344         #endif
 345         return -1;
 346 }
 347
 348 static int delete_data_watchpoint(stlink_t *sl, stm32_addr_t addr)
 349 {
 350         int i;
 351
 352         for(i = 0 ; i < DATA_WATCH_NUM; i++) {
 353                 if((data_watches[i].addr == addr) && (data_watches[i].fun != WATCHDISABLED)) {
 354                         #ifdef DEBUG
 355                         printf("delete watchpoint %d addr %x\n", i, addr);
 356                         #endif
 357
 358                         memset(sl->q_buf, 0, 4);
 359                         data_watches[i].fun = WATCHDISABLED;
 360                         stlink_write_mem32(sl, 0xe0001028 + i * 16, 4);
 361
 362                         return 0;
 363                 }
 364         }
 365
 366         #ifdef DEBUG
 367         printf("failure: delete watchpoint addr %x\n", addr);
 368         #endif
 369
 370         return -1;
 371 }
 372
 373 #define CODE_BREAK_NUM  6
 374 #define CODE_BREAK_LOW  0x01
 375 #define CODE_BREAK_HIGH 0x02
 376
 377 struct code_hw_breakpoint {
 378         stm32_addr_t addr;
 379         int          type;
 380 };
 381
 382 struct code_hw_breakpoint code_breaks[CODE_BREAK_NUM];
 383
 384 static void init_code_breakpoints(stlink_t *sl) {
 385         memset(sl->q_buf, 0, 4);
 386         sl->q_buf[0] = 0x03; // KEY | ENABLE
 387         stlink_write_mem32(sl, CM3_REG_FP_CTRL, 4);
 388         printf("KARL - should read back as 0x03, not 60 02 00 00\n");
 389         stlink_read_mem32(sl, CM3_REG_FP_CTRL, 4);
 390
 391         memset(sl->q_buf, 0, 4);
 392         for(int i = 0; i < CODE_BREAK_NUM; i++) {
 393                 code_breaks[i].type = 0;
 394                 stlink_write_mem32(sl, CM3_REG_FP_COMP0 + i * 4, 4);
 395         }
 396 }
 397
 398 static int update_code_breakpoint(stlink_t *sl, stm32_addr_t addr, int set) {
 399         stm32_addr_t fpb_addr = addr & ~0x3;
 400         int type = addr & 0x2 ? CODE_BREAK_HIGH : CODE_BREAK_LOW;
 401
 402         if(addr & 1) {
 403                 fprintf(stderr, "update_code_breakpoint: unaligned address %08x\n", addr);
 404                 return -1;
 405         }
 406
 407         int id = -1;
 408         for(int i = 0; i < CODE_BREAK_NUM; i++) {
 409                 if(fpb_addr == code_breaks[i].addr ||
 410                         (set && code_breaks[i].type == 0)) {
 411                         id = i;
 412                         break;
 413                 }
 414         }
 415
 416         if(id == -1) {
 417                 if(set) return -1; // Free slot not found
 418                 else    return 0;  // Breakpoint is already removed
 419         }
 420
 421         struct code_hw_breakpoint* brk = &code_breaks[id];
 422
 423         brk->addr = fpb_addr;
 424
 425         if(set) brk->type |= type;
 426         else    brk->type &= ~type;
 427
 428         memset(sl->q_buf, 0, 4);
 429
 430         if(brk->type == 0) {
 431                 #ifdef DEBUG
 432                 printf("clearing hw break %d\n", id);
 433                 #endif
 434
 435                 stlink_write_mem32(sl, 0xe0002008 + id * 4, 4);
 436         } else {
 437                 sl->q_buf[0] = ( brk->addr        & 0xff) | 1;
 438                 sl->q_buf[1] = ((brk->addr >> 8)  & 0xff);
 439                 sl->q_buf[2] = ((brk->addr >> 16) & 0xff);
 440                 sl->q_buf[3] = ((brk->addr >> 24) & 0xff) | (brk->type << 6);
 441
 442                 #ifdef DEBUG
 443                 printf("setting hw break %d at %08x (%d)\n",
 444                         id, brk->addr, brk->type);
 445                 printf("reg %02x %02x %02x %02x\n",
 446                         sl->q_buf[3], sl->q_buf[2], sl->q_buf[1], sl->q_buf[0]);
 447                 #endif
 448
 449                 stlink_write_mem32(sl, 0xe0002008 + id * 4, 4);
 450         }
 451
 452         return 0;
 453 }
 454
 455
 456 struct flash_block {
 457         stm32_addr_t addr;
 458         unsigned     length;
 459         uint8_t*     data;
 460
 461         struct flash_block* next;
 462 };
 463
 464 static struct flash_block* flash_root;
 465
 466 static int flash_add_block(stm32_addr_t addr, unsigned length,
 467                            stlink_t *sl) {
 468         if(addr < FLASH_BASE || addr + length > FLASH_BASE + FLASH_SIZE) {
 469                 fprintf(stderr, "flash_add_block: incorrect bounds\n");
 470                 return -1;
 471         }
 472
 473         if(addr % FLASH_PAGE != 0 || length % FLASH_PAGE != 0) {
 474                 fprintf(stderr, "flash_add_block: unaligned block\n");
 475                 return -1;
 476         }
 477
 478         struct flash_block* new = malloc(sizeof(struct flash_block));
 479         new->next = flash_root;
 480
 481         new->addr   = addr;
 482         new->length = length;
 483         new->data   = calloc(length, 1);
 484
 485         flash_root = new;
 486
 487         return 0;
 488 }
 489
 490 static int flash_populate(stm32_addr_t addr, uint8_t* data, unsigned length) {
 491         int fit_blocks = 0, fit_length = 0;
 492
 493         for(struct flash_block* fb = flash_root; fb; fb = fb->next) {
 494                 /* Block: ------X------Y--------
 495                  * Data:            a-----b
 496                  *                a--b
 497                  *            a-----------b
 498                  * Block intersects with data, if:
 499                  *  a < Y && b > x
 500                  */
 501
 502                 unsigned X = fb->addr, Y = fb->addr + fb->length;
 503                 unsigned a = addr, b = addr + length;
 504                 if(a < Y && b > X) {
 505                         // from start of the block
 506                         unsigned start = (a > X ? a : X) - X;
 507                         unsigned end   = (b > Y ? Y : b) - X;
 508
 509                         memcpy(fb->data + start, data, end - start);
 510
 511                         fit_blocks++;
 512                         fit_length += end - start;
 513                 }
 514         }
 515
 516         if(fit_blocks == 0) {
 517                 fprintf(stderr, "Unfit data block %08x -> %04x\n", addr, length);
 518                 return -1;
 519         }
 520
 521         if(fit_length != length) {
 522                 fprintf(stderr, "warning: data block %08x -> %04x truncated to %04x\n",
 523                         addr, length, fit_length);
 524                 fprintf(stderr, "(this is not an error, just a GDB glitch)\n");
 525         }
 526
 527         return 0;
 528 }
 529
 530 static int flash_go(stlink_t *sl) {
 531         int error = -1;
 532
 533         // Some kinds of clock settings do not allow writing to flash.
 534         stlink_reset(sl);
 535
 536         for(struct flash_block* fb = flash_root; fb; fb = fb->next) {
 537                 #ifdef DEBUG
 538                 printf("flash_do: block %08x -> %04x\n", fb->addr, fb->length);
 539                 #endif
 540
 541                 unsigned length = fb->length;
 542                 for(stm32_addr_t page = fb->addr; page < fb->addr + fb->length; page += FLASH_PAGE) {
 543                         #ifdef DEBUG
 544                         printf("flash_do: page %08x\n", page);
 545                         #endif
 546
 547                         stlink_erase_flash_page(sl, page);
 548
 549                         if(stlink_write_flash(sl, page, fb->data + (page - fb->addr),
 550                                         length > FLASH_PAGE ? FLASH_PAGE : length) < 0)
 551                                 goto error;
 552                 }
 553
 554         }
 555
 556         stlink_reset(sl);
 557
 558         error = 0;
 559
 560 error:
 561         for(struct flash_block* fb = flash_root, *next; fb; fb = next) {
 562                 next = fb->next;
 563                 free(fb->data);
 564                 free(fb);
 565         }
 566
 567         flash_root = NULL;
 568
 569         return error;
 570 }
 571
 572 int serve(stlink_t *sl, int port) {
 573         int sock = socket(AF_INET, SOCK_STREAM, 0);
 574         if(sock < 0) {
 575                 perror("socket");
 576                 return 1;
 577         }
 578
 579         unsigned int val = 1;
 580         setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
 581
 582         struct sockaddr_in serv_addr = {0};
 583         serv_addr.sin_family = AF_INET;
 584         serv_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
 585         serv_addr.sin_port = htons(port);
 586
 587         if(bind(sock, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0) {
 588                 perror("bind");
 589                 return 1;
 590         }
 591
 592         if(listen(sock, 5) < 0) {
 593                 perror("listen");
 594                 return 1;
 595         }
 596
 597         stlink_force_debug(sl);
 598         stlink_reset(sl);
 599         init_code_breakpoints(sl);
 600         init_data_watchpoints(sl);
 601
 602         printf("Listening at *:%d...\n", port);
 603
 604         (void) signal (SIGINT, ctrl_c);
 605         int client = accept(sock, NULL, NULL);
 606         signal (SIGINT, SIG_DFL);
 607         if(client < 0) {
 608                 perror("accept");
 609                 return 1;
 610         }
 611
 612         close(sock);
 613
 614         printf("GDB connected.\n");
 615
 616         /*
 617          * To allow resetting the chip from GDB it is required to
 618          * emulate attaching and detaching to target.
 619          */
 620         unsigned int attached = 1;
 621
 622         while(1) {
 623                 char* packet;
 624
 625                 int status = gdb_recv_packet(client, &packet);
 626                 if(status < 0) {
 627                         fprintf(stderr, "cannot recv: %d\n", status);
 628                         return 1;
 629                 }
 630
 631                 #ifdef DEBUG
 632                 printf("recv: %s\n", packet);
 633                 #endif
 634
 635                 char* reply = NULL;
 636                 reg regp;
 637
 638                 switch(packet[0]) {
 639                 case 'q': {
 640                         if(packet[1] == 'P' || packet[1] == 'C' || packet[1] == 'L') {
 641                                 reply = strdup("");
 642                                 break;
 643                         }
 644
 645                         char *separator = strstr(packet, ":"), *params = "";
 646                         if(separator == NULL) {
 647                                 separator = packet + strlen(packet);
 648                         } else {
 649                                 params = separator + 1;
 650                         }
 651
 652                         unsigned queryNameLength = (separator - &packet[1]);
 653                         char* queryName = calloc(queryNameLength + 1, 1);
 654                         strncpy(queryName, &packet[1], queryNameLength);
 655
 656                         #ifdef DEBUG
 657                         printf("query: %s;%s\n", queryName, params);
 658                         #endif
 659
 660                         if(!strcmp(queryName, "Supported")) {
 661                                 reply = strdup("PacketSize=3fff;qXfer:memory-map:read+");
 662                         } else if(!strcmp(queryName, "Xfer")) {
 663                                 char *type, *op, *s_addr, *s_length;
 664                                 char *tok = params;
 665                                 char *annex __attribute__((unused));
 666
 667                                 type     = strsep(&tok, ":");
 668                                 op       = strsep(&tok, ":");
 669                                 annex    = strsep(&tok, ":");
 670                                 s_addr   = strsep(&tok, ",");
 671                                 s_length = tok;
 672
 673                                 unsigned addr = strtoul(s_addr, NULL, 16),
 674                                        length = strtoul(s_length, NULL, 16);
 675
 676                                 #ifdef DEBUG
 677                                 printf("Xfer: type:%s;op:%s;annex:%s;addr:%d;length:%d\n",
 678                                         type, op, annex, addr, length);
 679                                 #endif
 680
 681                                 const char* data = NULL;
 682
 683                                 if(!strcmp(type, "memory-map") && !strcmp(op, "read"))
 684                                         data = current_memory_map;
 685
 686                                 if(data) {
 687                                         unsigned data_length = strlen(data);
 688                                         if(addr + length > data_length)
 689                                                 length = data_length - addr;
 690
 691                                         if(length == 0) {
 692                                                 reply = strdup("l");
 693                                         } else {
 694                                                 reply = calloc(length + 2, 1);
 695                                                 reply[0] = 'm';
 696                                                 strncpy(&reply[1], data, length);
 697                                         }
 698                                 }
 699                         }
 700
 701                         if(reply == NULL)
 702                                 reply = strdup("");
 703
 704                         free(queryName);
 705
 706                         break;
 707                 }
 708
 709                 case 'v': {
 710                         char *params = NULL;
 711                         char *cmdName = strtok_r(packet, ":;", &params);
 712
 713                         cmdName++; // vCommand -> Command
 714
 715                         if(!strcmp(cmdName, "FlashErase")) {
 716                                 char *s_addr, *s_length;
 717                                 char *tok = params;
 718
 719                                 s_addr   = strsep(&tok, ",");
 720                                 s_length = tok;
 721
 722                                 unsigned addr = strtoul(s_addr, NULL, 16),
 723                                        length = strtoul(s_length, NULL, 16);
 724
 725                                 #ifdef DEBUG
 726                                 printf("FlashErase: addr:%08x,len:%04x\n",
 727                                         addr, length);
 728                                 #endif
 729
 730                                 if(flash_add_block(addr, length, sl) < 0) {
 731                                         reply = strdup("E00");
 732                                 } else {
 733                                         reply = strdup("OK");
 734                                 }
 735                         } else if(!strcmp(cmdName, "FlashWrite")) {
 736                                 char *s_addr, *data;
 737                                 char *tok = params;
 738
 739                                 s_addr = strsep(&tok, ":");
 740                                 data   = tok;
 741
 742                                 unsigned addr = strtoul(s_addr, NULL, 16);
 743                                 unsigned data_length = status - (data - packet);
 744
 745                                 // Length of decoded data cannot be more than
 746                                 // encoded, as escapes are removed.
 747                                 // Additional byte is reserved for alignment fix.
 748                                 uint8_t *decoded = calloc(data_length + 1, 1);
 749                                 unsigned dec_index = 0;
 750                                 for(int i = 0; i < data_length; i++) {
 751                                         if(data[i] == 0x7d) {
 752                                                 i++;
 753                                                 decoded[dec_index++] = data[i] ^ 0x20;
 754                                         } else {
 755                                                 decoded[dec_index++] = data[i];
 756                                         }
 757                                 }
 758
 759                                 // Fix alignment
 760                                 if(dec_index % 2 != 0)
 761                                         dec_index++;
 762
 763                                 #ifdef DEBUG
 764                                 printf("binary packet %d -> %d\n", data_length, dec_index);
 765                                 #endif
 766
 767                                 if(flash_populate(addr, decoded, dec_index) < 0) {
 768                                         reply = strdup("E00");
 769                                 } else {
 770                                         reply = strdup("OK");
 771                                 }
 772                         } else if(!strcmp(cmdName, "FlashDone")) {
 773                                 if(flash_go(sl) < 0) {
 774                                         reply = strdup("E00");
 775                                 } else {
 776                                         reply = strdup("OK");
 777                                 }
 778                         } else if(!strcmp(cmdName, "Kill")) {
 779                                 attached = 0;
 780
 781                                 reply = strdup("OK");
 782                         }
 783
 784                         if(reply == NULL)
 785                                 reply = strdup("");
 786
 787                         break;
 788                 }
 789
 790                 case 'c':
 791                         stlink_run(sl);
 792
 793                         while(1) {
 794                                 int status = gdb_check_for_interrupt(client);
 795                                 if(status < 0) {
 796                                         fprintf(stderr, "cannot check for int: %d\n", status);
 797                                         return 1;
 798                                 }
 799
 800                                 if(status == 1) {
 801                                         stlink_force_debug(sl);
 802                                         break;
 803                                 }
 804
 805                                 stlink_status(sl);
 806                                 if(sl->core_stat == STLINK_CORE_HALTED) {
 807                                         break;
 808                                 }
 809
 810                                 usleep(100000);
 811                         }
 812
 813                         reply = strdup("S05"); // TRAP
 814                         break;
 815
 816                 case 's':
 817                         stlink_step(sl);
 818
 819                         reply = strdup("S05"); // TRAP
 820                         break;
 821
 822                 case '?':
 823                         if(attached) {
 824                                 reply = strdup("S05"); // TRAP
 825                         } else {
 826                                 /* Stub shall reply OK if not attached. */
 827                                 reply = strdup("OK");
 828                         }
 829                         break;
 830
 831                 case 'g':
 832                         stlink_read_all_regs(sl, &regp);
 833
 834                         reply = calloc(8 * 16 + 1, 1);
 835                         for(int i = 0; i < 16; i++)
 836                                 sprintf(&reply[i * 8], "%08x", htonl(regp.r[i]));
 837
 838                         break;
 839
 840                 case 'p': {
 841                         unsigned id = strtoul(&packet[1], NULL, 16);
 842                         unsigned myreg = 0xDEADDEAD;
 843
 844                         if(id < 16) {
 845                                 stlink_read_reg(sl, id, &regp);
 846                                 myreg = htonl(regp.r[id]);
 847                         } else if(id == 0x19) {
 848                                 stlink_read_reg(sl, 16, &regp);
 849                                 myreg = htonl(regp.xpsr);
 850                         } else {
 851                                 reply = strdup("E00");
 852                         }
 853
 854                         reply = calloc(8 + 1, 1);
 855                         sprintf(reply, "%08x", myreg);
 856
 857                         break;
 858                 }
 859
 860                 case 'P': {
 861                         char* s_reg = &packet[1];
 862                         char* s_value = strstr(&packet[1], "=") + 1;
 863
 864                         unsigned reg   = strtoul(s_reg,   NULL, 16);
 865                         unsigned value = strtoul(s_value, NULL, 16);
 866
 867                         if(reg < 16) {
 868                                 stlink_write_reg(sl, ntohl(value), reg);
 869                         } else if(reg == 0x19) {
 870                                 stlink_write_reg(sl, ntohl(value), 16);
 871                         } else {
 872                                 reply = strdup("E00");
 873                         }
 874
 875                         if(!reply) {
 876                                 reply = strdup("OK");
 877                         }
 878
 879                         break;
 880                 }
 881
 882                 case 'G':
 883                         for(int i = 0; i < 16; i++) {
 884                                 char str[9] = {0};
 885                                 strncpy(str, &packet[1 + i * 8], 8);
 886                                 uint32_t reg = strtoul(str, NULL, 16);
 887                                 stlink_write_reg(sl, ntohl(reg), i);
 888                         }
 889
 890                         reply = strdup("OK");
 891                         break;
 892
 893                 case 'm': {
 894                         char* s_start = &packet[1];
 895                         char* s_count = strstr(&packet[1], ",") + 1;
 896
 897                         stm32_addr_t start = strtoul(s_start, NULL, 16);
 898                         unsigned     count = strtoul(s_count, NULL, 16);
 899
 900                         unsigned adj_start = start % 4;
 901
 902                         stlink_read_mem32(sl, start - adj_start, (count % 4 == 0) ?
 903                                                 count : count + 4 - (count % 4));
 904
 905                         reply = calloc(count * 2 + 1, 1);
 906                         for(int i = 0; i < count; i++) {
 907                                 reply[i * 2 + 0] = hex[sl->q_buf[i + adj_start] >> 4];
 908                                 reply[i * 2 + 1] = hex[sl->q_buf[i + adj_start] & 0xf];
 909                         }
 910
 911                         break;
 912                 }
 913
 914                 case 'M': {
 915                         char* s_start = &packet[1];
 916                         char* s_count = strstr(&packet[1], ",") + 1;
 917                         char* hexdata = strstr(packet, ":") + 1;
 918
 919                         stm32_addr_t start = strtoul(s_start, NULL, 16);
 920                         unsigned     count = strtoul(s_count, NULL, 16);
 921
 922                         for(int i = 0; i < count; i ++) {
 923                                 char hex[3] = { hexdata[i*2], hexdata[i*2+1], 0 };
 924                                 uint8_t byte = strtoul(hex, NULL, 16);
 925                                 sl->q_buf[i] = byte;
 926                         }
 927
 928                         if((count % 4) == 0 && (start % 4) == 0) {
 929                                 stlink_write_mem32(sl, start, count);
 930                         } else {
 931                                 stlink_write_mem8(sl, start, count);
 932                         }
 933
 934                         reply = strdup("OK");
 935
 936                         break;
 937                 }
 938
 939                 case 'Z': {
 940                         char *endptr;
 941                         stm32_addr_t addr = strtoul(&packet[3], &endptr, 16);
 942                         stm32_addr_t len  = strtoul(&endptr[1], NULL, 16);
 943
 944                         switch (packet[1]) {
 945                                 case '1':
 946                                 if(update_code_breakpoint(sl, addr, 1) < 0) {
 947                                         reply = strdup("E00");
 948                                 } else {
 949                                         reply = strdup("OK");
 950                                 }
 951                                 break;
 952
 953                                 case '2':   // insert write watchpoint
 954                                 case '3':   // insert read  watchpoint
 955                                 case '4':   // insert access watchpoint
 956                                 {
 957                                         enum watchfun wf;
 958                                         if(packet[1] == '2') {
 959                                                 wf = WATCHWRITE;
 960                                         } else if(packet[1] == '3') {
 961                                                 wf = WATCHREAD;
 962                                         } else {
 963                                                 wf = WATCHACCESS;
 964                                                 if(add_data_watchpoint(sl, wf, addr, len) < 0) {
 965                                                         reply = strdup("E00");
 966                                                 } else {
 967                                                         reply = strdup("OK");
 968                                                         break;
 969                                                 }
 970                                         }
 971                                 }
 972
 973                                 default:
 974                                 reply = strdup("");
 975                         }
 976                         break;
 977                 }
 978                 case 'z': {
 979                         char *endptr;
 980                         stm32_addr_t addr = strtoul(&packet[3], &endptr, 16);
 981                         //stm32_addr_t len  = strtoul(&endptr[1], NULL, 16);
 982
 983                         switch (packet[1]) {
 984                                 case '1': // remove breakpoint
 985                                 update_code_breakpoint(sl, addr, 0);
 986                                 reply = strdup("OK");
 987                                 break;
 988
 989                                 case '2' : // remove write watchpoint
 990                                 case '3' : // remove read watchpoint
 991                                 case '4' : // remove access watchpoint
 992                                 if(delete_data_watchpoint(sl, addr) < 0) {
 993                                         reply = strdup("E00");
 994                                 } else {
 995                                         reply = strdup("OK");
 996                                         break;
 997                                 }
 998
 999                                 default:
1000                                 reply = strdup("");
1001                         }
1002                         break;
1003                 }
1004
1005                 case '!': {
1006                         /*
1007                          * Enter extended mode which allows restarting.
1008                          * We do support that always.
1009                          */
1010
1011                         reply = strdup("OK");
1012
1013                         break;
1014                 }
1015
1016                 case 'R': {
1017                         /* Reset the core. */
1018
1019                         stlink_reset(sl);
1020                         init_code_breakpoints(sl);
1021                         init_data_watchpoints(sl);
1022
1023                         attached = 1;
1024
1025                         reply = strdup("OK");
1026
1027                         break;
1028                 }
1029
1030                 default:
1031                         reply = strdup("");
1032                 }
1033
1034                 if(reply) {
1035                         #ifdef DEBUG
1036                         printf("send: %s\n", reply);
1037                         #endif
1038
1039                         int result = gdb_send_packet(client, reply);
1040                         if(result != 0) {
1041                                 fprintf(stderr, "cannot send: %d\n", result);
1042                                 return 1;
1043                         }
1044
1045                         free(reply);
1046                 }
1047
1048                 free(packet);
1049         }
1050
1051         return 0;
1052 }