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

   1 /* -*- tab-width:8 -*- */
   2 #define DEBUG 0
   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 <getopt.h>
  10 #include <stdio.h>
  11 #include <string.h>
  12 #include <stdlib.h>
  13 #include <unistd.h>
  14 #include <sys/types.h>
  15 #ifdef __MINGW32__
  16 #include "mingw.h"
  17 #else
  18 #include <sys/socket.h>
  19 #include <netinet/in.h>
  20 #include <arpa/inet.h>
  21 #include <signal.h>
  22 #endif
  23
  24 #include <stlink-common.h>
  25
  26 #include "gdb-remote.h"
  27
  28 #define DEFAULT_LOGGING_LEVEL 50
  29 #define DEFAULT_GDB_LISTEN_PORT 4242
  30
  31 #define STRINGIFY_inner(name) #name
  32 #define STRINGIFY(name) STRINGIFY_inner(name)
  33
  34 #define FLASH_BASE 0x08000000
  35
  36 //Allways update the FLASH_PAGE before each use, by calling stlink_calculate_pagesize
  37 #define FLASH_PAGE (sl->flash_pgsz)
  38
  39 stlink_t *connected_stlink = NULL;
  40
  41 static const char hex[] = "0123456789abcdef";
  42
  43 static const char* current_memory_map = NULL;
  44
  45 typedef struct _st_state_t {
  46     // things from command line, bleh
  47     int stlink_version;
  48     // "/dev/serial/by-id/usb-FTDI_TTL232R-3V3_FTE531X6-if00-port0" is only 58 chars
  49     char devicename[100];
  50     int logging_level;
  51         int listen_port;
  52     int persistent;
  53     int reset;
  54 } st_state_t;
  55
  56
  57 int serve(stlink_t *sl, st_state_t *st);
  58 char* make_memory_map(stlink_t *sl);
  59
  60 static void cleanup(int signal __attribute__((unused))) {
  61     if (connected_stlink) {
  62         /* Switch back to mass storage mode before closing. */
  63         stlink_run(connected_stlink);
  64         stlink_exit_debug_mode(connected_stlink);
  65         stlink_close(connected_stlink);
  66     }
  67
  68     exit(1);
  69 }
  70
  71
  72
  73 int parse_options(int argc, char** argv, st_state_t *st) {
  74     static struct option long_options[] = {
  75         {"help", no_argument, NULL, 'h'},
  76         {"verbose", optional_argument, NULL, 'v'},
  77         {"device", required_argument, NULL, 'd'},
  78         {"stlink_version", required_argument, NULL, 's'},
  79         {"stlinkv1", no_argument, NULL, '1'},
  80                 {"listen_port", required_argument, NULL, 'p'},
  81                 {"multi", optional_argument, NULL, 'm'},
  82                 {"no-reset", optional_argument, NULL, 'n'},
  83         {0, 0, 0, 0},
  84     };
  85         const char * help_str = "%s - usage:\n\n"
  86         "  -h, --help\t\tPrint this help\n"
  87         "  -vXX, --verbose=XX\tspecify a specific verbosity level (0..99)\n"
  88         "  -v, --verbose\tspecify generally verbose logging\n"
  89         "  -d <device>, --device=/dev/stlink2_1\n"
  90         "\t\t\tWhere is your stlink device connected?\n"
  91         "  -s X, --stlink_version=X\n"
  92         "\t\t\tChoose what version of stlink to use, (defaults to 2)\n"
  93         "  -1, --stlinkv1\tForce stlink version 1\n"
  94         "  -p 4242, --listen_port=1234\n"
  95         "\t\t\tSet the gdb server listen port. "
  96         "(default port: " STRINGIFY(DEFAULT_GDB_LISTEN_PORT) ")\n"
  97     "  -m, --multi\n"
  98     "\t\t\tSet gdb server to extended mode.\n"
  99     "\t\t\tst-util will continue listening for connections after disconnect.\n"
 100     "  -n, --no-reset\n"
 101     "\t\t\tDo not reset board on connection.\n"
 102         ;
 103
 104
 105     int option_index = 0;
 106     int c;
 107     int q;
 108     while ((c = getopt_long(argc, argv, "hv::d:s:1p:mn", long_options, &option_index)) != -1) {
 109         switch (c) {
 110         case 0:
 111             printf("XXXXX Shouldn't really normally come here, only if there's no corresponding option\n");
 112             printf("option %s", long_options[option_index].name);
 113             if (optarg) {
 114                 printf(" with arg %s", optarg);
 115             }
 116             printf("\n");
 117             break;
 118         case 'h':
 119             printf(help_str, argv[0]);
 120             exit(EXIT_SUCCESS);
 121             break;
 122         case 'v':
 123             if (optarg) {
 124                 st->logging_level = atoi(optarg);
 125             } else {
 126                 st->logging_level = DEFAULT_LOGGING_LEVEL;
 127             }
 128             break;
 129         case 'd':
 130             if (strlen(optarg) > sizeof (st->devicename)) {
 131                 fprintf(stderr, "device name too long: %zd\n", strlen(optarg));
 132             } else {
 133                 strcpy(st->devicename, optarg);
 134             }
 135             break;
 136                 case '1':
 137                         st->stlink_version = 1;
 138                         break;
 139                 case 's':
 140                         sscanf(optarg, "%i", &q);
 141                         if (q < 0 || q > 2) {
 142                                 fprintf(stderr, "stlink version %d unknown!\n", q);
 143                                 exit(EXIT_FAILURE);
 144                         }
 145                         st->stlink_version = q;
 146                         break;
 147                 case 'p':
 148                         sscanf(optarg, "%i", &q);
 149                         if (q < 0) {
 150                                 fprintf(stderr, "Can't use a negative port to listen on: %d\n", q);
 151                                 exit(EXIT_FAILURE);
 152                         }
 153                         st->listen_port = q;
 154                         break;
 155                 case 'm':
 156                         st->persistent = 1;
 157                         break;
 158                 case 'n':
 159                         st->reset = 0;
 160                         break;
 161         }
 162     }
 163
 164     if (optind < argc) {
 165         printf("non-option ARGV-elements: ");
 166         while (optind < argc)
 167             printf("%s ", argv[optind++]);
 168         printf("\n");
 169     }
 170     return 0;
 171 }
 172
 173
 174 int main(int argc, char** argv) {
 175
 176         stlink_t *sl = NULL;
 177
 178         st_state_t state;
 179         memset(&state, 0, sizeof(state));
 180         // set defaults...
 181         state.stlink_version = 2;
 182         state.logging_level = DEFAULT_LOGGING_LEVEL;
 183         state.listen_port = DEFAULT_GDB_LISTEN_PORT;
 184         state.reset = 1;    /* By default, reset board */
 185         parse_options(argc, argv, &state);
 186         switch (state.stlink_version) {
 187         case 2:
 188                 sl = stlink_open_usb(state.logging_level, 0);
 189                 if(sl == NULL) return 1;
 190                 break;
 191         case 1:
 192                 sl = stlink_v1_open(state.logging_level, 0);
 193                 if(sl == NULL) return 1;
 194                 break;
 195     }
 196
 197     connected_stlink = sl;
 198     signal(SIGINT, &cleanup);
 199     signal(SIGTERM, &cleanup);
 200
 201     if (state.reset) {
 202                 stlink_reset(sl);
 203     }
 204
 205         printf("Chip ID is %08x, Core ID is  %08x.\n", sl->chip_id, sl->core_id);
 206
 207         sl->verbose=0;
 208
 209         current_memory_map = make_memory_map(sl);
 210
 211 #ifdef __MINGW32__
 212         WSADATA wsadata;
 213         if (WSAStartup(MAKEWORD(2,2),&wsadata) !=0 ) {
 214                 goto winsock_error;
 215         }
 216 #endif
 217
 218         do {
 219                 serve(sl, &state);
 220
 221                 /* Continue */
 222                 stlink_run(sl);
 223         } while (state.persistent);
 224
 225 #ifdef __MINGW32__
 226 winsock_error:
 227         WSACleanup();
 228 #endif
 229
 230         /* Switch back to mass storage mode before closing. */
 231         stlink_exit_debug_mode(sl);
 232         stlink_close(sl);
 233
 234         return 0;
 235 }
 236
 237 static const char* const target_description_F4 =
 238     "<?xml version=\"1.0\"?>"
 239     "<!DOCTYPE target SYSTEM \"gdb-target.dtd\">"
 240     "<target version=\"1.0\">"
 241     "   <architecture>arm</architecture>"
 242     "   <feature name=\"org.gnu.gdb.arm.m-profile\">"
 243     "       <reg name=\"r0\" bitsize=\"32\"/>"
 244     "       <reg name=\"r1\" bitsize=\"32\"/>"
 245     "       <reg name=\"r2\" bitsize=\"32\"/>"
 246     "       <reg name=\"r3\" bitsize=\"32\"/>"
 247     "       <reg name=\"r4\" bitsize=\"32\"/>"
 248     "       <reg name=\"r5\" bitsize=\"32\"/>"
 249     "       <reg name=\"r6\" bitsize=\"32\"/>"
 250     "       <reg name=\"r7\" bitsize=\"32\"/>"
 251     "       <reg name=\"r8\" bitsize=\"32\"/>"
 252     "       <reg name=\"r9\" bitsize=\"32\"/>"
 253     "       <reg name=\"r10\" bitsize=\"32\"/>"
 254     "       <reg name=\"r11\" bitsize=\"32\"/>"
 255     "       <reg name=\"r12\" bitsize=\"32\"/>"
 256     "       <reg name=\"sp\" bitsize=\"32\" type=\"data_ptr\"/>"
 257     "       <reg name=\"lr\" bitsize=\"32\"/>"
 258     "       <reg name=\"pc\" bitsize=\"32\" type=\"code_ptr\"/>"
 259     "       <reg name=\"xpsr\" bitsize=\"32\" regnum=\"25\"/>"
 260     "       <reg name=\"msp\" bitsize=\"32\" regnum=\"26\" type=\"data_ptr\" group=\"general\" />"
 261     "       <reg name=\"psp\" bitsize=\"32\" regnum=\"27\" type=\"data_ptr\" group=\"general\" />"
 262     "       <reg name=\"control\" bitsize=\"8\" regnum=\"28\" type=\"int\" group=\"general\" />"
 263     "       <reg name=\"faultmask\" bitsize=\"8\" regnum=\"29\" type=\"int\" group=\"general\" />"
 264     "       <reg name=\"basepri\" bitsize=\"8\" regnum=\"30\" type=\"int\" group=\"general\" />"
 265     "       <reg name=\"primask\" bitsize=\"8\" regnum=\"31\" type=\"int\" group=\"general\" />"
 266     "       <reg name=\"s0\" bitsize=\"32\" regnum=\"32\" type=\"float\" group=\"float\" />"
 267     "       <reg name=\"s1\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 268     "       <reg name=\"s2\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 269     "       <reg name=\"s3\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 270     "       <reg name=\"s4\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 271     "       <reg name=\"s5\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 272     "       <reg name=\"s6\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 273     "       <reg name=\"s7\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 274     "       <reg name=\"s8\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 275     "       <reg name=\"s9\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 276     "       <reg name=\"s10\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 277     "       <reg name=\"s11\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 278     "       <reg name=\"s12\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 279     "       <reg name=\"s13\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 280     "       <reg name=\"s14\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 281     "       <reg name=\"s15\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 282     "       <reg name=\"s16\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 283     "       <reg name=\"s17\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 284     "       <reg name=\"s18\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 285     "       <reg name=\"s19\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 286     "       <reg name=\"s20\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 287     "       <reg name=\"s21\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 288     "       <reg name=\"s22\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 289     "       <reg name=\"s23\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 290     "       <reg name=\"s24\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 291     "       <reg name=\"s25\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 292     "       <reg name=\"s26\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 293     "       <reg name=\"s27\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 294     "       <reg name=\"s28\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 295     "       <reg name=\"s29\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 296     "       <reg name=\"s30\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 297     "       <reg name=\"s31\" bitsize=\"32\" type=\"float\" group=\"float\" />"
 298     "       <reg name=\"fpscr\" bitsize=\"32\" type=\"int\" group=\"float\" />"
 299     "   </feature>"
 300     "</target>";
 301
 302 static const char* const memory_map_template_F4 =
 303   "<?xml version=\"1.0\"?>"
 304   "<!DOCTYPE memory-map PUBLIC \"+//IDN gnu.org//DTD GDB Memory Map V1.0//EN\""
 305   "     \"http://sourceware.org/gdb/gdb-memory-map.dtd\">"
 306   "<memory-map>"
 307   "  <memory type=\"rom\" start=\"0x00000000\" length=\"0x100000\"/>"       // code = sram, bootrom or flash; flash is bigger
 308   "  <memory type=\"ram\" start=\"0x10000000\" length=\"0x10000\"/>"        // ccm ram
 309   "  <memory type=\"ram\" start=\"0x20000000\" length=\"0x20000\"/>"        // sram
 310   "  <memory type=\"flash\" start=\"0x08000000\" length=\"0x10000\">"           //Sectors 0..3
 311   "    <property name=\"blocksize\">0x4000</property>"                                          //16kB
 312   "  </memory>"
 313   "  <memory type=\"flash\" start=\"0x08010000\" length=\"0x10000\">"           //Sector 4
 314   "    <property name=\"blocksize\">0x10000</property>"                                         //64kB
 315   "  </memory>"
 316   "  <memory type=\"flash\" start=\"0x08020000\" length=\"0x70000\">"           //Sectors 5..11
 317   "    <property name=\"blocksize\">0x20000</property>"                                         //128kB
 318   "  </memory>"
 319   "  <memory type=\"ram\" start=\"0x40000000\" length=\"0x1fffffff\"/>"         // peripheral regs
 320   "  <memory type=\"ram\" start=\"0xe0000000\" length=\"0x1fffffff\"/>"         // cortex regs
 321   "  <memory type=\"rom\" start=\"0x1fff0000\" length=\"0x7800\"/>"         // bootrom
 322   "  <memory type=\"rom\" start=\"0x1fffc000\" length=\"0x10\"/>"               // option byte area
 323   "</memory-map>";
 324
 325 static const char* const memory_map_template =
 326   "<?xml version=\"1.0\"?>"
 327   "<!DOCTYPE memory-map PUBLIC \"+//IDN gnu.org//DTD GDB Memory Map V1.0//EN\""
 328   "     \"http://sourceware.org/gdb/gdb-memory-map.dtd\">"
 329   "<memory-map>"
 330   "  <memory type=\"rom\" start=\"0x00000000\" length=\"0x%zx\"/>"       // code = sram, bootrom or flash; flash is bigger
 331   "  <memory type=\"ram\" start=\"0x20000000\" length=\"0x%zx\"/>"       // sram 8k
 332   "  <memory type=\"flash\" start=\"0x08000000\" length=\"0x%zx\">"
 333   "    <property name=\"blocksize\">0x%zx</property>"
 334   "  </memory>"
 335   "  <memory type=\"ram\" start=\"0x40000000\" length=\"0x1fffffff\"/>" // peripheral regs
 336   "  <memory type=\"ram\" start=\"0xe0000000\" length=\"0x1fffffff\"/>" // cortex regs
 337   "  <memory type=\"rom\" start=\"0x%08x\" length=\"0x%zx\"/>"           // bootrom
 338   "  <memory type=\"rom\" start=\"0x1ffff800\" length=\"0x10\"/>"        // option byte area
 339   "</memory-map>";
 340
 341 char* make_memory_map(stlink_t *sl) {
 342         /* This will be freed in serve() */
 343         char* map = malloc(4096);
 344         map[0] = '\0';
 345
 346         if(sl->chip_id==STM32_CHIPID_F4) {
 347         strcpy(map, memory_map_template_F4);
 348     } else {
 349         snprintf(map, 4096, memory_map_template,
 350                         sl->flash_size,
 351                         sl->sram_size,
 352                         sl->flash_size, sl->flash_pgsz,
 353                         sl->sys_base, sl->sys_size);
 354     }
 355         return map;
 356 }
 357
 358
 359 /*
 360  * DWT_COMP0     0xE0001020
 361  * DWT_MASK0     0xE0001024
 362  * DWT_FUNCTION0 0xE0001028
 363  * DWT_COMP1     0xE0001030
 364  * DWT_MASK1     0xE0001034
 365  * DWT_FUNCTION1 0xE0001038
 366  * DWT_COMP2     0xE0001040
 367  * DWT_MASK2     0xE0001044
 368  * DWT_FUNCTION2 0xE0001048
 369  * DWT_COMP3     0xE0001050
 370  * DWT_MASK3     0xE0001054
 371  * DWT_FUNCTION3 0xE0001058
 372  */
 373
 374 #define DATA_WATCH_NUM 4
 375
 376 enum watchfun { WATCHDISABLED = 0, WATCHREAD = 5, WATCHWRITE = 6, WATCHACCESS = 7 };
 377
 378 struct code_hw_watchpoint {
 379         stm32_addr_t addr;
 380         uint8_t mask;
 381         enum watchfun fun;
 382 };
 383
 384 struct code_hw_watchpoint data_watches[DATA_WATCH_NUM];
 385
 386 static void init_data_watchpoints(stlink_t *sl) {
 387         #if DEBUG
 388         printf("init watchpoints\n");
 389         #endif
 390
 391         // set trcena in debug command to turn on dwt unit
 392         stlink_write_debug32(sl, 0xE000EDFC,
 393                              stlink_read_debug32(sl, 0xE000EDFC) | (1<<24));
 394
 395         // make sure all watchpoints are cleared
 396         for(int i = 0; i < DATA_WATCH_NUM; i++) {
 397                 data_watches[i].fun = WATCHDISABLED;
 398                 stlink_write_debug32(sl, 0xe0001028 + i * 16, 0);
 399         }
 400 }
 401
 402 static int add_data_watchpoint(stlink_t *sl, enum watchfun wf, stm32_addr_t addr, unsigned int len)
 403 {
 404         int i = 0;
 405         uint32_t mask;
 406
 407         // computer mask
 408         // find a free watchpoint
 409         // configure
 410
 411         mask = -1;
 412         i = len;
 413         while(i) {
 414                 i >>= 1;
 415                 mask++;
 416         }
 417
 418         if((mask != (uint32_t)-1) && (mask < 16)) {
 419                 for(i = 0; i < DATA_WATCH_NUM; i++) {
 420                         // is this an empty slot ?
 421                         if(data_watches[i].fun == WATCHDISABLED) {
 422                                 #if DEBUG
 423                                 printf("insert watchpoint %d addr %x wf %u mask %u len %d\n", i, addr, wf, mask, len);
 424                                 #endif
 425
 426                                 data_watches[i].fun = wf;
 427                                 data_watches[i].addr = addr;
 428                                 data_watches[i].mask = mask;
 429
 430                                 // insert comparator address
 431                                 stlink_write_debug32(sl, 0xE0001020 + i * 16, addr);
 432
 433                                 // insert mask
 434                                 stlink_write_debug32(sl, 0xE0001024 + i * 16, mask);
 435
 436                                 // insert function
 437                                 stlink_write_debug32(sl, 0xE0001028 + i * 16, wf);
 438
 439                                 // just to make sure the matched bit is clear !
 440                                 stlink_read_debug32(sl,  0xE0001028 + i * 16);
 441                                 return 0;
 442                         }
 443                 }
 444         }
 445
 446         #if DEBUG
 447         printf("failure: add watchpoints addr %x wf %u len %u\n", addr, wf, len);
 448         #endif
 449         return -1;
 450 }
 451
 452 static int delete_data_watchpoint(stlink_t *sl, stm32_addr_t addr)
 453 {
 454         int i;
 455
 456         for(i = 0 ; i < DATA_WATCH_NUM; i++) {
 457                 if((data_watches[i].addr == addr) && (data_watches[i].fun != WATCHDISABLED)) {
 458                         #if DEBUG
 459                         printf("delete watchpoint %d addr %x\n", i, addr);
 460                         #endif
 461
 462                         data_watches[i].fun = WATCHDISABLED;
 463                         stlink_write_debug32(sl, 0xe0001028 + i * 16, 0);
 464
 465                         return 0;
 466                 }
 467         }
 468
 469         #if DEBUG
 470         printf("failure: delete watchpoint addr %x\n", addr);
 471         #endif
 472
 473         return -1;
 474 }
 475
 476 #define CODE_BREAK_NUM  6
 477 #define CODE_BREAK_LOW  0x01
 478 #define CODE_BREAK_HIGH 0x02
 479
 480 struct code_hw_breakpoint {
 481         stm32_addr_t addr;
 482         int          type;
 483 };
 484
 485 struct code_hw_breakpoint code_breaks[CODE_BREAK_NUM];
 486
 487 static void init_code_breakpoints(stlink_t *sl) {
 488         memset(sl->q_buf, 0, 4);
 489         stlink_write_debug32(sl, CM3_REG_FP_CTRL, 0x03 /*KEY | ENABLE4*/);
 490         printf("KARL - should read back as 0x03, not 60 02 00 00\n");
 491         stlink_read_debug32(sl, CM3_REG_FP_CTRL);
 492
 493         for(int i = 0; i < CODE_BREAK_NUM; i++) {
 494                 code_breaks[i].type = 0;
 495                 stlink_write_debug32(sl, CM3_REG_FP_COMP0 + i * 4, 0);
 496         }
 497 }
 498
 499 static int update_code_breakpoint(stlink_t *sl, stm32_addr_t addr, int set) {
 500         stm32_addr_t fpb_addr = addr & ~0x3;
 501         int type = addr & 0x2 ? CODE_BREAK_HIGH : CODE_BREAK_LOW;
 502
 503         if(addr & 1) {
 504                 fprintf(stderr, "update_code_breakpoint: unaligned address %08x\n", addr);
 505                 return -1;
 506         }
 507
 508         int id = -1;
 509         for(int i = 0; i < CODE_BREAK_NUM; i++) {
 510                 if(fpb_addr == code_breaks[i].addr ||
 511                         (set && code_breaks[i].type == 0)) {
 512                         id = i;
 513                         break;
 514                 }
 515         }
 516
 517         if(id == -1) {
 518                 if(set) return -1; // Free slot not found
 519                 else    return 0;  // Breakpoint is already removed
 520         }
 521
 522         struct code_hw_breakpoint* brk = &code_breaks[id];
 523
 524         brk->addr = fpb_addr;
 525
 526         if(set) brk->type |= type;
 527         else    brk->type &= ~type;
 528
 529         if(brk->type == 0) {
 530                 #if DEBUG
 531                 printf("clearing hw break %d\n", id);
 532                 #endif
 533
 534                 stlink_write_debug32(sl, 0xe0002008 + id * 4, 0);
 535         } else {
 536                 uint32_t mask = (brk->addr) | 1 | (brk->type << 30);
 537
 538                 #if DEBUG
 539                 printf("setting hw break %d at %08x (%d)\n",
 540                         id, brk->addr, brk->type);
 541                 printf("reg %08x \n",
 542                         mask);
 543                 #endif
 544
 545                 stlink_write_debug32(sl, 0xe0002008 + id * 4, mask);
 546         }
 547
 548         return 0;
 549 }
 550
 551
 552 struct flash_block {
 553         stm32_addr_t addr;
 554         unsigned     length;
 555         uint8_t*     data;
 556
 557         struct flash_block* next;
 558 };
 559
 560 static struct flash_block* flash_root;
 561
 562 static int flash_add_block(stm32_addr_t addr, unsigned length, stlink_t *sl) {
 563
 564         if(addr < FLASH_BASE || addr + length > FLASH_BASE + sl->flash_size) {
 565                 fprintf(stderr, "flash_add_block: incorrect bounds\n");
 566                 return -1;
 567         }
 568
 569         stlink_calculate_pagesize(sl, addr);
 570         if(addr % FLASH_PAGE != 0 || length % FLASH_PAGE != 0) {
 571                 fprintf(stderr, "flash_add_block: unaligned block\n");
 572                 return -1;
 573         }
 574
 575         struct flash_block* new = malloc(sizeof(struct flash_block));
 576         new->next = flash_root;
 577
 578         new->addr   = addr;
 579         new->length = length;
 580         new->data   = calloc(length, 1);
 581
 582         flash_root = new;
 583
 584         return 0;
 585 }
 586
 587 static int flash_populate(stm32_addr_t addr, uint8_t* data, unsigned length) {
 588         unsigned int fit_blocks = 0, fit_length = 0;
 589
 590         for(struct flash_block* fb = flash_root; fb; fb = fb->next) {
 591                 /* Block: ------X------Y--------
 592                  * Data:            a-----b
 593                  *                a--b
 594                  *            a-----------b
 595                  * Block intersects with data, if:
 596                  *  a < Y && b > x
 597                  */
 598
 599                 unsigned X = fb->addr, Y = fb->addr + fb->length;
 600                 unsigned a = addr, b = addr + length;
 601                 if(a < Y && b > X) {
 602                         // from start of the block
 603                         unsigned start = (a > X ? a : X) - X;
 604                         unsigned end   = (b > Y ? Y : b) - X;
 605
 606                         memcpy(fb->data + start, data, end - start);
 607
 608                         fit_blocks++;
 609                         fit_length += end - start;
 610                 }
 611         }
 612
 613         if(fit_blocks == 0) {
 614                 fprintf(stderr, "Unfit data block %08x -> %04x\n", addr, length);
 615                 return -1;
 616         }
 617
 618         if(fit_length != length) {
 619                 fprintf(stderr, "warning: data block %08x -> %04x truncated to %04x\n",
 620                         addr, length, fit_length);
 621                 fprintf(stderr, "(this is not an error, just a GDB glitch)\n");
 622         }
 623
 624         return 0;
 625 }
 626
 627 static int flash_go(stlink_t *sl) {
 628         int error = -1;
 629
 630         // Some kinds of clock settings do not allow writing to flash.
 631         stlink_reset(sl);
 632
 633         for(struct flash_block* fb = flash_root; fb; fb = fb->next) {
 634                 #if DEBUG
 635                 printf("flash_do: block %08x -> %04x\n", fb->addr, fb->length);
 636                 #endif
 637
 638                 unsigned length = fb->length;
 639                 for(stm32_addr_t page = fb->addr; page < fb->addr + fb->length; page += FLASH_PAGE) {
 640
 641                         //Update FLASH_PAGE
 642                         stlink_calculate_pagesize(sl, page);
 643
 644                         #if DEBUG
 645                         printf("flash_do: page %08x\n", page);
 646                         #endif
 647
 648                         if(stlink_write_flash(sl, page, fb->data + (page - fb->addr),
 649                                         length > FLASH_PAGE ? FLASH_PAGE : length) < 0)
 650                                 goto error;
 651                         }
 652         }
 653
 654         stlink_reset(sl);
 655
 656         error = 0;
 657
 658 error:
 659         for(struct flash_block* fb = flash_root, *next; fb; fb = next) {
 660                 next = fb->next;
 661                 free(fb->data);
 662                 free(fb);
 663         }
 664
 665         flash_root = NULL;
 666
 667         return error;
 668 }
 669
 670 int serve(stlink_t *sl, st_state_t *st) {
 671         int sock = socket(AF_INET, SOCK_STREAM, 0);
 672         if(sock < 0) {
 673                 perror("socket");
 674                 return 1;
 675         }
 676
 677         unsigned int val = 1;
 678         setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (char *)&val, sizeof(val));
 679
 680         struct sockaddr_in serv_addr;
 681         memset(&serv_addr,0,sizeof(struct sockaddr_in));
 682         serv_addr.sin_family = AF_INET;
 683         serv_addr.sin_addr.s_addr = INADDR_ANY;
 684         serv_addr.sin_port = htons(st->listen_port);
 685
 686         if(bind(sock, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0) {
 687                 perror("bind");
 688                 return 1;
 689         }
 690
 691         if(listen(sock, 5) < 0) {
 692                 perror("listen");
 693                 return 1;
 694         }
 695
 696         printf("Listening at *:%d...\n", st->listen_port);
 697
 698         int client = accept(sock, NULL, NULL);
 699         //signal (SIGINT, SIG_DFL);
 700         if(client < 0) {
 701                 perror("accept");
 702                 return 1;
 703         }
 704
 705         close(sock);
 706
 707         stlink_force_debug(sl);
 708         if (st->reset) {
 709                 stlink_reset(sl);
 710     }
 711         init_code_breakpoints(sl);
 712         init_data_watchpoints(sl);
 713
 714         printf("GDB connected.\n");
 715
 716         /*
 717          * To allow resetting the chip from GDB it is required to
 718          * emulate attaching and detaching to target.
 719          */
 720         unsigned int attached = 1;
 721
 722         while(1) {
 723                 char* packet;
 724
 725                 int status = gdb_recv_packet(client, &packet);
 726                 if(status < 0) {
 727                         fprintf(stderr, "cannot recv: %d\n", status);
 728                         return 1;
 729                 }
 730
 731                 #if DEBUG
 732                 printf("recv: %s\n", packet);
 733                 #endif
 734
 735                 char* reply = NULL;
 736                 reg regp;
 737
 738                 switch(packet[0]) {
 739                 case 'q': {
 740                         if(packet[1] == 'P' || packet[1] == 'C' || packet[1] == 'L') {
 741                                 reply = strdup("");
 742                                 break;
 743                         }
 744
 745                         char *separator = strstr(packet, ":"), *params = "";
 746                         if(separator == NULL) {
 747                                 separator = packet + strlen(packet);
 748                         } else {
 749                                 params = separator + 1;
 750                         }
 751
 752                         unsigned queryNameLength = (separator - &packet[1]);
 753                         char* queryName = calloc(queryNameLength + 1, 1);
 754                         strncpy(queryName, &packet[1], queryNameLength);
 755
 756                         #if DEBUG
 757                         printf("query: %s;%s\n", queryName, params);
 758                         #endif
 759
 760                         if(!strcmp(queryName, "Supported")) {
 761                 if(sl->chip_id==STM32_CHIPID_F4) {
 762                     reply = strdup("PacketSize=3fff;qXfer:memory-map:read+;qXfer:features:read+");
 763                 }
 764                 else {
 765                     reply = strdup("PacketSize=3fff;qXfer:memory-map:read+");
 766                 }
 767                         } else if(!strcmp(queryName, "Xfer")) {
 768                                 char *type, *op, *__s_addr, *s_length;
 769                                 char *tok = params;
 770                                 char *annex __attribute__((unused));
 771
 772                                 type     = strsep(&tok, ":");
 773                                 op       = strsep(&tok, ":");
 774                                 annex    = strsep(&tok, ":");
 775                                 __s_addr   = strsep(&tok, ",");
 776                                 s_length = tok;
 777
 778                                 unsigned addr = strtoul(__s_addr, NULL, 16),
 779                                        length = strtoul(s_length, NULL, 16);
 780
 781                                 #if DEBUG
 782                                 printf("Xfer: type:%s;op:%s;annex:%s;addr:%d;length:%d\n",
 783                                         type, op, annex, addr, length);
 784                                 #endif
 785
 786                                 const char* data = NULL;
 787
 788                                 if(!strcmp(type, "memory-map") && !strcmp(op, "read"))
 789                                         data = current_memory_map;
 790
 791                                 if(!strcmp(type, "features") && !strcmp(op, "read"))
 792                                         data = target_description_F4;
 793
 794                                 if(data) {
 795                                         unsigned data_length = strlen(data);
 796                                         if(addr + length > data_length)
 797                                                 length = data_length - addr;
 798
 799                                         if(length == 0) {
 800                                                 reply = strdup("l");
 801                                         } else {
 802                                                 reply = calloc(length + 2, 1);
 803                                                 reply[0] = 'm';
 804                                                 strncpy(&reply[1], data, length);
 805                                         }
 806                                 }
 807                         } else if(!strncmp(queryName, "Rcmd,",4)) {
 808                                 // Rcmd uses the wrong separator
 809                                 char *separator = strstr(packet, ","), *params = "";
 810                                 if(separator == NULL) {
 811                                         separator = packet + strlen(packet);
 812                                 } else {
 813                                         params = separator + 1;
 814                                 }
 815
 816
 817                                 if (!strncmp(params,"726573756d65",12)) {// resume
 818 #if DEBUG
 819                                         printf("Rcmd: resume\n");
 820 #endif
 821                                         stlink_run(sl);
 822
 823                                         reply = strdup("OK");
 824                 } else if (!strncmp(params,"68616c74",8)) { //halt
 825                                         reply = strdup("OK");
 826
 827                                         stlink_force_debug(sl);
 828
 829 #if DEBUG
 830                                         printf("Rcmd: halt\n");
 831 #endif
 832                 } else if (!strncmp(params,"6a7461675f7265736574",20)) { //jtag_reset
 833                                         reply = strdup("OK");
 834
 835                                         stlink_jtag_reset(sl, 1);
 836                                         stlink_jtag_reset(sl, 0);
 837                                         stlink_force_debug(sl);
 838
 839 #if DEBUG
 840                                         printf("Rcmd: jtag_reset\n");
 841 #endif
 842                 } else if (!strncmp(params,"7265736574",10)) { //reset
 843                                         reply = strdup("OK");
 844
 845                                         stlink_force_debug(sl);
 846                                         stlink_reset(sl);
 847                                         init_code_breakpoints(sl);
 848                                         init_data_watchpoints(sl);
 849
 850 #if DEBUG
 851                                         printf("Rcmd: reset\n");
 852 #endif
 853                                 } else {
 854 #if DEBUG
 855                                         printf("Rcmd: %s\n", params);
 856 #endif
 857
 858                                 }
 859
 860                         }
 861
 862                         if(reply == NULL)
 863                                 reply = strdup("");
 864
 865                         free(queryName);
 866
 867                         break;
 868                 }
 869
 870                 case 'v': {
 871                         char *params = NULL;
 872                         char *cmdName = strtok_r(packet, ":;", &params);
 873
 874                         cmdName++; // vCommand -> Command
 875
 876                         if(!strcmp(cmdName, "FlashErase")) {
 877                                 char *__s_addr, *s_length;
 878                                 char *tok = params;
 879
 880                                 __s_addr   = strsep(&tok, ",");
 881                                 s_length = tok;
 882
 883                                 unsigned addr = strtoul(__s_addr, NULL, 16),
 884                                        length = strtoul(s_length, NULL, 16);
 885
 886                                 #if DEBUG
 887                                 printf("FlashErase: addr:%08x,len:%04x\n",
 888                                         addr, length);
 889                                 #endif
 890
 891                                 if(flash_add_block(addr, length, sl) < 0) {
 892                                         reply = strdup("E00");
 893                                 } else {
 894                                         reply = strdup("OK");
 895                                 }
 896                         } else if(!strcmp(cmdName, "FlashWrite")) {
 897                                 char *__s_addr, *data;
 898                                 char *tok = params;
 899
 900                                 __s_addr = strsep(&tok, ":");
 901                                 data   = tok;
 902
 903                                 unsigned addr = strtoul(__s_addr, NULL, 16);
 904                                 unsigned data_length = status - (data - packet);
 905
 906                                 // Length of decoded data cannot be more than
 907                                 // encoded, as escapes are removed.
 908                                 // Additional byte is reserved for alignment fix.
 909                                 uint8_t *decoded = calloc(data_length + 1, 1);
 910                                 unsigned dec_index = 0;
 911                                 for(unsigned int i = 0; i < data_length; i++) {
 912                                         if(data[i] == 0x7d) {
 913                                                 i++;
 914                                                 decoded[dec_index++] = data[i] ^ 0x20;
 915                                         } else {
 916                                                 decoded[dec_index++] = data[i];
 917                                         }
 918                                 }
 919
 920                                 // Fix alignment
 921                                 if(dec_index % 2 != 0)
 922                                         dec_index++;
 923
 924                                 #if DEBUG
 925                                 printf("binary packet %d -> %d\n", data_length, dec_index);
 926                                 #endif
 927
 928                                 if(flash_populate(addr, decoded, dec_index) < 0) {
 929                                         reply = strdup("E00");
 930                                 } else {
 931                                         reply = strdup("OK");
 932                                 }
 933                         } else if(!strcmp(cmdName, "FlashDone")) {
 934                                 if(flash_go(sl) < 0) {
 935                                         reply = strdup("E00");
 936                                 } else {
 937                                         reply = strdup("OK");
 938                                 }
 939                         } else if(!strcmp(cmdName, "Kill")) {
 940                                 attached = 0;
 941
 942                                 reply = strdup("OK");
 943                         }
 944
 945                         if(reply == NULL)
 946                                 reply = strdup("");
 947
 948                         break;
 949                 }
 950
 951                 case 'c':
 952                         stlink_run(sl);
 953
 954                         while(1) {
 955                                 int status = gdb_check_for_interrupt(client);
 956                                 if(status < 0) {
 957                                         fprintf(stderr, "cannot check for int: %d\n", status);
 958                                         return 1;
 959                                 }
 960
 961                                 if(status == 1) {
 962                                         stlink_force_debug(sl);
 963                                         break;
 964                                 }
 965
 966                                 stlink_status(sl);
 967                                 if(sl->core_stat == STLINK_CORE_HALTED) {
 968                                         break;
 969                                 }
 970
 971                                 usleep(100000);
 972                         }
 973
 974                         reply = strdup("S05"); // TRAP
 975                         break;
 976
 977                 case 's':
 978                         stlink_step(sl);
 979
 980                         reply = strdup("S05"); // TRAP
 981                         break;
 982
 983                 case '?':
 984                         if(attached) {
 985                                 reply = strdup("S05"); // TRAP
 986                         } else {
 987                                 /* Stub shall reply OK if not attached. */
 988                                 reply = strdup("OK");
 989                         }
 990                         break;
 991
 992                 case 'g':
 993                         stlink_read_all_regs(sl, &regp);
 994
 995                         reply = calloc(8 * 16 + 1, 1);
 996                         for(int i = 0; i < 16; i++)
 997                                 sprintf(&reply[i * 8], "%08x", htonl(regp.r[i]));
 998
 999                         break;
1000
1001                 case 'p': {
1002                         unsigned id = strtoul(&packet[1], NULL, 16);
1003                         unsigned myreg = 0xDEADDEAD;
1004
1005                         if(id < 16) {
1006                                 stlink_read_reg(sl, id, &regp);
1007                                 myreg = htonl(regp.r[id]);
1008                         } else if(id == 0x19) {
1009                                 stlink_read_reg(sl, 16, &regp);
1010                                 myreg = htonl(regp.xpsr);
1011                         } else if(id == 0x1A) {
1012                                 stlink_read_reg(sl, 17, &regp);
1013                                 myreg = htonl(regp.main_sp);
1014                         } else if(id == 0x1B) {
1015                                 stlink_read_reg(sl, 18, &regp);
1016                                 myreg = htonl(regp.process_sp);
1017                         } else if(id == 0x1C) {
1018                                 stlink_read_unsupported_reg(sl, id, &regp);
1019                                 myreg = htonl(regp.control);
1020                         } else if(id == 0x1D) {
1021                                 stlink_read_unsupported_reg(sl, id, &regp);
1022                                 myreg = htonl(regp.faultmask);
1023                         } else if(id == 0x1E) {
1024                                 stlink_read_unsupported_reg(sl, id, &regp);
1025                                 myreg = htonl(regp.basepri);
1026                         } else if(id == 0x1F) {
1027                                 stlink_read_unsupported_reg(sl, id, &regp);
1028                                 myreg = htonl(regp.primask);
1029             } else if(id >= 0x20 && id < 0x40) {
1030                 stlink_read_unsupported_reg(sl, id, &regp);
1031                 myreg = htonl(regp.s[id-0x20]);
1032                         } else if(id == 0x40) {
1033                 stlink_read_unsupported_reg(sl, id, &regp);
1034                 myreg = htonl(regp.fpscr);
1035                         } else {
1036                                 reply = strdup("E00");
1037                         }
1038
1039                         reply = calloc(8 + 1, 1);
1040                         sprintf(reply, "%08x", myreg);
1041
1042                         break;
1043                 }
1044
1045                 case 'P': {
1046                         char* s_reg = &packet[1];
1047                         char* s_value = strstr(&packet[1], "=") + 1;
1048
1049                         unsigned reg   = strtoul(s_reg,   NULL, 16);
1050                         unsigned value = strtoul(s_value, NULL, 16);
1051
1052                         if(reg < 16) {
1053                                 stlink_write_reg(sl, ntohl(value), reg);
1054                         } else if(reg == 0x19) {
1055                                 stlink_write_reg(sl, ntohl(value), 16);
1056                         } else if(reg == 0x1A) {
1057                                 stlink_write_reg(sl, ntohl(value), 17);
1058                         } else if(reg == 0x1B) {
1059                                 stlink_write_reg(sl, ntohl(value), 18);
1060                         } else if(reg == 0x1C) {
1061                                 stlink_write_unsupported_reg(sl, ntohl(value), reg, &regp);
1062                         } else if(reg == 0x1D) {
1063                                 stlink_write_unsupported_reg(sl, ntohl(value), reg, &regp);
1064                         } else if(reg == 0x1E) {
1065                                 stlink_write_unsupported_reg(sl, ntohl(value), reg, &regp);
1066                         } else if(reg == 0x1F) {
1067                                 stlink_write_unsupported_reg(sl, ntohl(value), reg, &regp);
1068             } else if(reg >= 0x20 && reg < 0x40) {
1069                 stlink_write_unsupported_reg(sl, ntohl(value), reg, &regp);
1070                         } else if(reg == 0x40) {
1071                 stlink_write_unsupported_reg(sl, ntohl(value), reg, &regp);
1072                         } else {
1073                                 reply = strdup("E00");
1074                         }
1075
1076                         if(!reply) {
1077                                 reply = strdup("OK");
1078                         }
1079
1080                         break;
1081                 }
1082
1083                 case 'G':
1084                         for(int i = 0; i < 16; i++) {
1085                                 char str[9] = {0};
1086                                 strncpy(str, &packet[1 + i * 8], 8);
1087                                 uint32_t reg = strtoul(str, NULL, 16);
1088                                 stlink_write_reg(sl, ntohl(reg), i);
1089                         }
1090
1091                         reply = strdup("OK");
1092                         break;
1093
1094                 case 'm': {
1095                         char* s_start = &packet[1];
1096                         char* s_count = strstr(&packet[1], ",") + 1;
1097
1098                         stm32_addr_t start = strtoul(s_start, NULL, 16);
1099                         unsigned     count = strtoul(s_count, NULL, 16);
1100
1101                         unsigned adj_start = start % 4;
1102                         unsigned count_rnd = (count + adj_start + 4 - 1) / 4 * 4;
1103
1104                         stlink_read_mem32(sl, start - adj_start, count_rnd);
1105
1106                         reply = calloc(count * 2 + 1, 1);
1107                         for(unsigned int i = 0; i < count; i++) {
1108                                 reply[i * 2 + 0] = hex[sl->q_buf[i + adj_start] >> 4];
1109                                 reply[i * 2 + 1] = hex[sl->q_buf[i + adj_start] & 0xf];
1110                         }
1111
1112                         break;
1113                 }
1114
1115                 case 'M': {
1116                         char* s_start = &packet[1];
1117                         char* s_count = strstr(&packet[1], ",") + 1;
1118                         char* hexdata = strstr(packet, ":") + 1;
1119
1120                         stm32_addr_t start = strtoul(s_start, NULL, 16);
1121                         unsigned     count = strtoul(s_count, NULL, 16);
1122
1123                         if(start % 4) {
1124                           unsigned align_count = 4 - start % 4;
1125                           if (align_count > count) align_count = count;
1126                           for(unsigned int i = 0; i < align_count; i ++) {
1127                                 char hex[3] = { hexdata[i*2], hexdata[i*2+1], 0 };
1128                                 uint8_t byte = strtoul(hex, NULL, 16);
1129                                 sl->q_buf[i] = byte;
1130                           }
1131                           stlink_write_mem8(sl, start, align_count);
1132                           start += align_count;
1133                           count -= align_count;
1134                           hexdata += 2*align_count;
1135                         }
1136
1137                         if(count - count % 4) {
1138                           unsigned aligned_count = count - count % 4;
1139
1140                           for(unsigned int i = 0; i < aligned_count; i ++) {
1141                             char hex[3] = { hexdata[i*2], hexdata[i*2+1], 0 };
1142                             uint8_t byte = strtoul(hex, NULL, 16);
1143                             sl->q_buf[i] = byte;
1144                           }
1145                           stlink_write_mem32(sl, start, aligned_count);
1146                           count -= aligned_count;
1147                           start += aligned_count;
1148                           hexdata += 2*aligned_count;
1149                         }
1150
1151                         if(count) {
1152                           for(unsigned int i = 0; i < count; i ++) {
1153                             char hex[3] = { hexdata[i*2], hexdata[i*2+1], 0 };
1154                             uint8_t byte = strtoul(hex, NULL, 16);
1155                             sl->q_buf[i] = byte;
1156                           }
1157                           stlink_write_mem8(sl, start, count);
1158                         }
1159                         reply = strdup("OK");
1160                         break;
1161                 }
1162
1163                 case 'Z': {
1164                         char *endptr;
1165                         stm32_addr_t addr = strtoul(&packet[3], &endptr, 16);
1166                         stm32_addr_t len  = strtoul(&endptr[1], NULL, 16);
1167
1168                         switch (packet[1]) {
1169                                 case '1':
1170                                 if(update_code_breakpoint(sl, addr, 1) < 0) {
1171                                         reply = strdup("E00");
1172                                 } else {
1173                                         reply = strdup("OK");
1174                                 }
1175                                 break;
1176
1177                                 case '2':   // insert write watchpoint
1178                                 case '3':   // insert read  watchpoint
1179                                 case '4':   // insert access watchpoint
1180                                 {
1181                                         enum watchfun wf;
1182                                         if(packet[1] == '2') {
1183                                                 wf = WATCHWRITE;
1184                                         } else if(packet[1] == '3') {
1185                                                 wf = WATCHREAD;
1186                                         } else {
1187                                                 wf = WATCHACCESS;
1188                                         }
1189
1190                     if(add_data_watchpoint(sl, wf, addr, len) < 0) {
1191                         reply = strdup("E00");
1192                     } else {
1193                         reply = strdup("OK");
1194                         break;
1195                     }
1196                                 }
1197
1198                                 default:
1199                                 reply = strdup("");
1200                         }
1201                         break;
1202                 }
1203                 case 'z': {
1204                         char *endptr;
1205                         stm32_addr_t addr = strtoul(&packet[3], &endptr, 16);
1206                         //stm32_addr_t len  = strtoul(&endptr[1], NULL, 16);
1207
1208                         switch (packet[1]) {
1209                                 case '1': // remove breakpoint
1210                                 update_code_breakpoint(sl, addr, 0);
1211                                 reply = strdup("OK");
1212                                 break;
1213
1214                                 case '2' : // remove write watchpoint
1215                                 case '3' : // remove read watchpoint
1216                                 case '4' : // remove access watchpoint
1217                                 if(delete_data_watchpoint(sl, addr) < 0) {
1218                                         reply = strdup("E00");
1219                                 } else {
1220                                         reply = strdup("OK");
1221                                         break;
1222                                 }
1223
1224                                 default:
1225                                 reply = strdup("");
1226                         }
1227                         break;
1228                 }
1229
1230                 case '!': {
1231                         /*
1232                          * Enter extended mode which allows restarting.
1233                          * We do support that always.
1234                          */
1235
1236                         /*
1237                          * Also, set to persistent mode
1238                          * to allow GDB disconnect.
1239                          */
1240                         st->persistent = 1;
1241
1242                         reply = strdup("OK");
1243
1244                         break;
1245                 }
1246
1247                 case 'R': {
1248                         /* Reset the core. */
1249
1250                         stlink_reset(sl);
1251                         init_code_breakpoints(sl);
1252                         init_data_watchpoints(sl);
1253
1254                         attached = 1;
1255
1256                         reply = strdup("OK");
1257
1258                         break;
1259                 }
1260
1261                 default:
1262                         reply = strdup("");
1263                 }
1264
1265                 if(reply) {
1266                         #if DEBUG
1267                         printf("send: %s\n", reply);
1268                         #endif
1269
1270                         int result = gdb_send_packet(client, reply);
1271                         if(result != 0) {
1272                                 fprintf(stderr, "cannot send: %d\n", result);
1273                                 free(reply);
1274                                 free(packet);
1275                                 return 1;
1276                         }
1277
1278                         free(reply);
1279                 }
1280
1281                 free(packet);
1282         }
1283
1284         return 0;
1285 }