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 <getopt.h>
  10 #include <stdio.h>
  11 #include <string.h>
  12 #include <stdlib.h>
  13 #include <unistd.h>
  14 #include <sys/types.h>
  15 #include <sys/socket.h>
  16 #include <netinet/in.h>
  17 #include <arpa/inet.h>
  18 #include <signal.h>
  19
  20 #include <stlink-common.h>
  21
  22 #include "gdb-remote.h"
  23
  24 #define DEFAULT_LOGGING_LEVEL 100
  25 #define DEFAULT_GDB_LISTEN_PORT 4242
  26
  27 #define STRINGIFY_inner(name) #name
  28 #define STRINGIFY(name) STRINGIFY_inner(name)
  29
  30 #define FLASH_BASE 0x08000000
  31 #define FLASH_PAGE (sl->flash_pgsz)
  32 #define FLASH_PAGE_MASK (~((1 << 10) - 1))
  33 #define FLASH_SIZE (FLASH_PAGE * 128)
  34
  35 static const char hex[] = "0123456789abcdef";
  36
  37 static const char* current_memory_map = NULL;
  38
  39 /*
  40  * Chip IDs are explained in the appropriate programming manual for the
  41  * DBGMCU_IDCODE register (0xE0042000)
  42  */
  43
  44 #define CORE_M3_R1 0x1BA00477
  45 #define CORE_M3_R2 0x4BA00477
  46 #define CORE_M4_R0 0x2BA01477
  47
  48 struct chip_params {
  49         uint32_t chip_id;
  50         char* description;
  51         uint32_t flash_size_reg;
  52         uint32_t max_flash_size, flash_pagesize;
  53         uint32_t sram_size;
  54         uint32_t bootrom_base, bootrom_size;
  55 } const devices[] = {
  56         { 0x410, "F1 Medium-density device", 0x1ffff7e0,
  57           0x20000,  0x400, 0x5000,  0x1ffff000, 0x800  }, // table 2, pm0063
  58         { 0x411, "F2 device", 0, /* No flash size register found in the docs*/
  59           0x100000,   0x20000, 0x20000, 0x1fff0000, 0x7800  }, // table 1, pm0059
  60         { 0x412, "F1 Low-density device", 0x1ffff7e0,
  61           0x8000,   0x400, 0x2800,  0x1ffff000, 0x800  }, // table 1, pm0063
  62         { 0x413, "F4 device", 0x1FFF7A10,
  63           0x100000,   0x20000, 0x30000,  0x1fff0000, 0x7800  }, // table 1, pm0081
  64         { 0x414, "F1 High-density device", 0x1ffff7e0,
  65           0x80000,  0x800, 0x10000, 0x1ffff000, 0x800  },  // table 3 pm0063
  66           // This ignores the EEPROM! (and uses the page erase size,
  67           // not the sector write protection...)
  68         { 0x416, "L1 Med-density device", 0x1FF8004C, // table 1, pm0062
  69           0x20000, 0x100, 0x4000, 0x1ff00000, 0x1000 },
  70         { 0x418, "F1 Connectivity line device", 0x1ffff7e0,
  71           0x40000,  0x800, 0x10000, 0x1fffb000, 0x4800 },
  72         { 0x420, "F1 Medium-density value line device", 0x1ffff7e0,
  73           0x20000,  0x400, 0x2000,  0x1ffff000, 0x800  },
  74         { 0x428, "F1 High-density value line device", 0x1ffff7e0,
  75           0x80000,  0x800, 0x8000,  0x1ffff000, 0x800  },
  76         { 0x430, "F1 XL-density device", 0x1ffff7e0,  // pm0068
  77           0x100000, 0x800, 0x18000, 0x1fffe000, 0x1800 },
  78         { 0 }
  79 };
  80
  81 typedef struct _st_state_t {
  82     // things from command line, bleh
  83     int stlink_version;
  84     // "/dev/serial/by-id/usb-FTDI_TTL232R-3V3_FTE531X6-if00-port0" is only 58 chars
  85     char devicename[100];
  86     int logging_level;
  87         int listen_port;
  88 } st_state_t;
  89
  90
  91 int serve(stlink_t *sl, int port);
  92 char* make_memory_map(const struct chip_params *params, uint32_t flash_size);
  93
  94
  95 int parse_options(int argc, char** argv, st_state_t *st) {
  96     static struct option long_options[] = {
  97         {"help", no_argument, NULL, 'h'},
  98         {"verbose", optional_argument, NULL, 'v'},
  99         {"device", required_argument, NULL, 'd'},
 100         {"stlink_version", required_argument, NULL, 's'},
 101         {"stlinkv1", no_argument, NULL, '1'},
 102                 {"listen_port", required_argument, NULL, 'p'},
 103         {0, 0, 0, 0},
 104     };
 105         const char * help_str = "%s - usage:\n\n"
 106         "  -h, --help\t\tPrint this help\n"
 107         "  -vXX, --verbose=XX\tspecify a specific verbosity level (0..99)\n"
 108         "  -v, --verbose\tspecify generally verbose logging\n"
 109         "  -d <device>, --device=/dev/stlink2_1\n"
 110         "\t\t\tWhere is your stlink device connected?\n"
 111         "  -s X, --stlink_version=X\n"
 112         "\t\t\tChoose what version of stlink to use, (defaults to 2)\n"
 113         "  -1, --stlinkv1\tForce stlink version 1\n"
 114         "  -p 4242, --listen_port=1234\n"
 115         "\t\t\tSet the gdb server listen port. "
 116         "(default port: " STRINGIFY(DEFAULT_GDB_LISTEN_PORT) ")\n"
 117         ;
 118
 119
 120     int option_index = 0;
 121     int c;
 122     int q;
 123     while ((c = getopt_long(argc, argv, "hv::d:s:1p:", long_options, &option_index)) != -1) {
 124         switch (c) {
 125         case 0:
 126             printf("XXXXX Shouldn't really normally come here, only if there's no corresponding option\n");
 127             printf("option %s", long_options[option_index].name);
 128             if (optarg) {
 129                 printf(" with arg %s", optarg);
 130             }
 131             printf("\n");
 132             break;
 133         case 'h':
 134             printf(help_str, argv[0]);
 135             exit(EXIT_SUCCESS);
 136             break;
 137         case 'v':
 138             if (optarg) {
 139                 st->logging_level = atoi(optarg);
 140             } else {
 141                 st->logging_level = DEFAULT_LOGGING_LEVEL;
 142             }
 143             break;
 144         case 'd':
 145             if (strlen(optarg) > sizeof (st->devicename)) {
 146                 fprintf(stderr, "device name too long: %ld\n", strlen(optarg));
 147             } else {
 148                 strcpy(st->devicename, optarg);
 149             }
 150             break;
 151                 case '1':
 152                         st->stlink_version = 1;
 153                         break;
 154                 case 's':
 155                         sscanf(optarg, "%i", &q);
 156                         if (q < 0 || q > 2) {
 157                                 fprintf(stderr, "stlink version %d unknown!\n", q);
 158                                 exit(EXIT_FAILURE);
 159                         }
 160                         st->stlink_version = q;
 161                         break;
 162                 case 'p':
 163                         sscanf(optarg, "%i", &q);
 164                         if (q < 0) {
 165                                 fprintf(stderr, "Can't use a negative port to listen on: %d\n", q);
 166                                 exit(EXIT_FAILURE);
 167                         }
 168                         st->listen_port = q;
 169                         break;
 170         }
 171     }
 172
 173     if (optind < argc) {
 174         printf("non-option ARGV-elements: ");
 175         while (optind < argc)
 176             printf("%s ", argv[optind++]);
 177         printf("\n");
 178     }
 179     return 0;
 180 }
 181
 182
 183 int main(int argc, char** argv) {
 184
 185         stlink_t *sl = NULL;
 186
 187         st_state_t state;
 188         memset(&state, 0, sizeof(state));
 189         // set defaults...
 190         state.stlink_version = 2;
 191         state.logging_level = DEFAULT_LOGGING_LEVEL;
 192         state.listen_port = DEFAULT_GDB_LISTEN_PORT;
 193         parse_options(argc, argv, &state);
 194         switch (state.stlink_version) {
 195         case 2:
 196                 sl = stlink_open_usb(state.logging_level);
 197                 if(sl == NULL) return 1;
 198                 break;
 199         case 1:
 200                 if (strlen(state.devicename) == 0) {
 201                         const int DevNumMax = 99;
 202                         int ExistDevCount = 0;
 203
 204                         for (int DevNum = 0; DevNum <= DevNumMax; DevNum++) {
 205                                 if (DevNum < 10) {
 206                                         char DevName[] = "/dev/sgX";
 207                                         const int X_index = 7;
 208                                         DevName[X_index] = DevNum + '0';
 209                                         if (!access(DevName, F_OK)) {
 210                                                 sl = stlink_v1_open(DevName, 0);
 211                                                 ExistDevCount++;
 212                                         }
 213                                 } else if (DevNum < 100) {
 214                                         char DevName[] = "/dev/sgXY";
 215                                         const int X_index = 7;
 216                                         const int Y_index = 8;
 217                                         DevName[X_index] = DevNum / 10 + '0';
 218                                         DevName[Y_index] = DevNum % 10 + '0';
 219                                         if (!access(DevName, F_OK)) {
 220                                                 sl = stlink_v1_open(DevName, 0);
 221                                                 ExistDevCount++;
 222                                         }
 223                                 }
 224                                 if (sl != NULL) break;
 225                         }
 226
 227                         if (sl == NULL) {
 228                                 fprintf(stdout, "\nNumber of /dev/sgX devices found: %i \n",
 229                                         ExistDevCount);
 230                                 fprintf(stderr, "ST-LINK not found\n");
 231                                 return 1;
 232                         }
 233                 } else {
 234                         sl = stlink_v1_open(state.devicename, state.logging_level);
 235                 }
 236                 break;
 237     }
 238
 239     if (stlink_current_mode(sl) != STLINK_DEV_DEBUG_MODE) {
 240         if (stlink_current_mode(sl) == STLINK_DEV_DFU_MODE) {
 241             stlink_exit_dfu_mode(sl);
 242         }
 243         stlink_enter_swd_mode(sl);
 244     }
 245
 246         uint32_t chip_id = stlink_chip_id(sl);
 247         uint32_t core_id = stlink_core_id(sl);
 248
 249         /* Fix chip_id for F4 */
 250         if (((chip_id & 0xFFF) == 0x411) && (core_id == CORE_M4_R0)) {
 251           printf("Fixing wrong chip_id for STM32F4 Rev A errata\n");
 252           chip_id = 0x413;
 253         }
 254
 255         printf("Chip ID is %08x, Core ID is  %08x.\n", chip_id, core_id);
 256
 257         const struct chip_params* params = NULL;
 258
 259         for(int i = 0; i < sizeof(devices) / sizeof(devices[0]); i++) {
 260                 if(devices[i].chip_id == (chip_id & 0xFFF)) {
 261                         params = &devices[i];
 262                         break;
 263                 }
 264         }
 265
 266         if(params == NULL) {
 267                 fprintf(stderr, "Cannot recognize the connected device!\n");
 268                 return 0;
 269         }
 270
 271         printf("Device connected: %s\n", params->description);
 272         printf("Device parameters: SRAM: 0x%x bytes, Flash: up to 0x%x bytes in pages of 0x%x bytes\n",
 273                 params->sram_size, params->max_flash_size, params->flash_pagesize);
 274
 275         FLASH_PAGE = params->flash_pagesize;
 276
 277         uint32_t flash_size;
 278
 279         stlink_read_mem32(sl, params->flash_size_reg, 4);
 280         flash_size = sl->q_buf[0] | (sl->q_buf[1] << 8);
 281
 282         printf("Flash size is %d KiB.\n", flash_size);
 283         // memory map is in 1k blocks.
 284         current_memory_map = make_memory_map(params, flash_size * 0x400);
 285
 286         while(serve(sl, state.listen_port) == 0);
 287
 288         /* Switch back to mass storage mode before closing. */
 289         stlink_run(sl);
 290         stlink_exit_debug_mode(sl);
 291         stlink_close(sl);
 292
 293         return 0;
 294 }
 295
 296 static const char* const memory_map_template =
 297   "<?xml version=\"1.0\"?>"
 298   "<!DOCTYPE memory-map PUBLIC \"+//IDN gnu.org//DTD GDB Memory Map V1.0//EN\""
 299   "     \"http://sourceware.org/gdb/gdb-memory-map.dtd\">"
 300   "<memory-map>"
 301   "  <memory type=\"rom\" start=\"0x00000000\" length=\"0x%x\"/>"       // code = sram, bootrom or flash; flash is bigger
 302   "  <memory type=\"ram\" start=\"0x20000000\" length=\"0x%x\"/>"       // sram 8k
 303   "  <memory type=\"flash\" start=\"0x08000000\" length=\"0x%x\">"
 304   "    <property name=\"blocksize\">0x%x</property>"
 305   "  </memory>"
 306   "  <memory type=\"ram\" start=\"0x40000000\" length=\"0x1fffffff\"/>" // peripheral regs
 307   "  <memory type=\"ram\" start=\"0xe0000000\" length=\"0x1fffffff\"/>" // cortex regs
 308   "  <memory type=\"rom\" start=\"0x%08x\" length=\"0x%x\"/>"           // bootrom
 309   "  <memory type=\"rom\" start=\"0x1ffff800\" length=\"0x8\"/>"        // option byte area
 310   "</memory-map>";
 311
 312 char* make_memory_map(const struct chip_params *params, uint32_t flash_size) {
 313         /* This will be freed in serve() */
 314         char* map = malloc(4096);
 315         map[0] = '\0';
 316
 317         snprintf(map, 4096, memory_map_template,
 318                         flash_size,
 319                         params->sram_size,
 320                         flash_size, params->flash_pagesize,
 321                         params->bootrom_base, params->bootrom_size);
 322
 323         return map;
 324 }
 325
 326
 327 /*
 328  * DWT_COMP0     0xE0001020
 329  * DWT_MASK0     0xE0001024
 330  * DWT_FUNCTION0 0xE0001028
 331  * DWT_COMP1     0xE0001030
 332  * DWT_MASK1     0xE0001034
 333  * DWT_FUNCTION1 0xE0001038
 334  * DWT_COMP2     0xE0001040
 335  * DWT_MASK2     0xE0001044
 336  * DWT_FUNCTION2 0xE0001048
 337  * DWT_COMP3     0xE0001050
 338  * DWT_MASK3     0xE0001054
 339  * DWT_FUNCTION3 0xE0001058
 340  */
 341
 342 #define DATA_WATCH_NUM 4
 343
 344 enum watchfun { WATCHDISABLED = 0, WATCHREAD = 5, WATCHWRITE = 6, WATCHACCESS = 7 };
 345
 346 struct code_hw_watchpoint {
 347         stm32_addr_t addr;
 348         uint8_t mask;
 349         enum watchfun fun;
 350 };
 351
 352 struct code_hw_watchpoint data_watches[DATA_WATCH_NUM];
 353
 354 static void init_data_watchpoints(stlink_t *sl) {
 355         #ifdef DEBUG
 356         printf("init watchpoints\n");
 357         #endif
 358
 359         // set trcena in debug command to turn on dwt unit
 360         stlink_read_mem32(sl, 0xE000EDFC, 4);
 361         sl->q_buf[3] |= 1;
 362         stlink_write_mem32(sl, 0xE000EDFC, 4);
 363
 364         // make sure all watchpoints are cleared
 365         memset(sl->q_buf, 0, 4);
 366         for(int i = 0; i < DATA_WATCH_NUM; i++) {
 367                 data_watches[i].fun = WATCHDISABLED;
 368                 stlink_write_mem32(sl, 0xe0001028 + i * 16, 4);
 369         }
 370 }
 371
 372 static int add_data_watchpoint(stlink_t *sl, enum watchfun wf, stm32_addr_t addr, unsigned int len)
 373 {
 374         int i = 0;
 375         uint32_t mask;
 376
 377         // computer mask
 378         // find a free watchpoint
 379         // configure
 380
 381         mask = -1;
 382         i = len;
 383         while(i) {
 384                 i >>= 1;
 385                 mask++;
 386         }
 387
 388         if((mask != -1) && (mask < 16)) {
 389                 for(i = 0; i < DATA_WATCH_NUM; i++) {
 390                         // is this an empty slot ?
 391                         if(data_watches[i].fun == WATCHDISABLED) {
 392                                 #ifdef DEBUG
 393                                 printf("insert watchpoint %d addr %x wf %u mask %u len %d\n", i, addr, wf, mask, len);
 394                                 #endif
 395
 396                                 data_watches[i].fun = wf;
 397                                 data_watches[i].addr = addr;
 398                                 data_watches[i].mask = mask;
 399
 400                                 // insert comparator address
 401                                 sl->q_buf[0] = (addr & 0xff);
 402                                 sl->q_buf[1] = ((addr >> 8) & 0xff);
 403                                 sl->q_buf[2] = ((addr >> 16) & 0xff);
 404                                 sl->q_buf[3] = ((addr >> 24)  & 0xff);
 405
 406                                 stlink_write_mem32(sl, 0xE0001020 + i * 16, 4);
 407
 408                                 // insert mask
 409                                 memset(sl->q_buf, 0, 4);
 410                                 sl->q_buf[0] = mask;
 411                                 stlink_write_mem32(sl, 0xE0001024 + i * 16, 4);
 412
 413                                 // insert function
 414                                 memset(sl->q_buf, 0, 4);
 415                                 sl->q_buf[0] = wf;
 416                                 stlink_write_mem32(sl, 0xE0001028 + i * 16, 4);
 417
 418                                 // just to make sure the matched bit is clear !
 419                                 stlink_read_mem32(sl,  0xE0001028 + i * 16, 4);
 420                                 return 0;
 421                         }
 422                 }
 423         }
 424
 425         #ifdef DEBUG
 426         printf("failure: add watchpoints addr %x wf %u len %u\n", addr, wf, len);
 427         #endif
 428         return -1;
 429 }
 430
 431 static int delete_data_watchpoint(stlink_t *sl, stm32_addr_t addr)
 432 {
 433         int i;
 434
 435         for(i = 0 ; i < DATA_WATCH_NUM; i++) {
 436                 if((data_watches[i].addr == addr) && (data_watches[i].fun != WATCHDISABLED)) {
 437                         #ifdef DEBUG
 438                         printf("delete watchpoint %d addr %x\n", i, addr);
 439                         #endif
 440
 441                         memset(sl->q_buf, 0, 4);
 442                         data_watches[i].fun = WATCHDISABLED;
 443                         stlink_write_mem32(sl, 0xe0001028 + i * 16, 4);
 444
 445                         return 0;
 446                 }
 447         }
 448
 449         #ifdef DEBUG
 450         printf("failure: delete watchpoint addr %x\n", addr);
 451         #endif
 452
 453         return -1;
 454 }
 455
 456 #define CODE_BREAK_NUM  6
 457 #define CODE_BREAK_LOW  0x01
 458 #define CODE_BREAK_HIGH 0x02
 459
 460 struct code_hw_breakpoint {
 461         stm32_addr_t addr;
 462         int          type;
 463 };
 464
 465 struct code_hw_breakpoint code_breaks[CODE_BREAK_NUM];
 466
 467 static void init_code_breakpoints(stlink_t *sl) {
 468         memset(sl->q_buf, 0, 4);
 469         sl->q_buf[0] = 0x03; // KEY | ENABLE
 470         stlink_write_mem32(sl, CM3_REG_FP_CTRL, 4);
 471         printf("KARL - should read back as 0x03, not 60 02 00 00\n");
 472         stlink_read_mem32(sl, CM3_REG_FP_CTRL, 4);
 473
 474         memset(sl->q_buf, 0, 4);
 475         for(int i = 0; i < CODE_BREAK_NUM; i++) {
 476                 code_breaks[i].type = 0;
 477                 stlink_write_mem32(sl, CM3_REG_FP_COMP0 + i * 4, 4);
 478         }
 479 }
 480
 481 static int update_code_breakpoint(stlink_t *sl, stm32_addr_t addr, int set) {
 482         stm32_addr_t fpb_addr = addr & ~0x3;
 483         int type = addr & 0x2 ? CODE_BREAK_HIGH : CODE_BREAK_LOW;
 484
 485         if(addr & 1) {
 486                 fprintf(stderr, "update_code_breakpoint: unaligned address %08x\n", addr);
 487                 return -1;
 488         }
 489
 490         int id = -1;
 491         for(int i = 0; i < CODE_BREAK_NUM; i++) {
 492                 if(fpb_addr == code_breaks[i].addr ||
 493                         (set && code_breaks[i].type == 0)) {
 494                         id = i;
 495                         break;
 496                 }
 497         }
 498
 499         if(id == -1) {
 500                 if(set) return -1; // Free slot not found
 501                 else    return 0;  // Breakpoint is already removed
 502         }
 503
 504         struct code_hw_breakpoint* brk = &code_breaks[id];
 505
 506         brk->addr = fpb_addr;
 507
 508         if(set) brk->type |= type;
 509         else    brk->type &= ~type;
 510
 511         memset(sl->q_buf, 0, 4);
 512
 513         if(brk->type == 0) {
 514                 #ifdef DEBUG
 515                 printf("clearing hw break %d\n", id);
 516                 #endif
 517
 518                 stlink_write_mem32(sl, 0xe0002008 + id * 4, 4);
 519         } else {
 520                 sl->q_buf[0] = ( brk->addr        & 0xff) | 1;
 521                 sl->q_buf[1] = ((brk->addr >> 8)  & 0xff);
 522                 sl->q_buf[2] = ((brk->addr >> 16) & 0xff);
 523                 sl->q_buf[3] = ((brk->addr >> 24) & 0xff) | (brk->type << 6);
 524
 525                 #ifdef DEBUG
 526                 printf("setting hw break %d at %08x (%d)\n",
 527                         id, brk->addr, brk->type);
 528                 printf("reg %02x %02x %02x %02x\n",
 529                         sl->q_buf[3], sl->q_buf[2], sl->q_buf[1], sl->q_buf[0]);
 530                 #endif
 531
 532                 stlink_write_mem32(sl, 0xe0002008 + id * 4, 4);
 533         }
 534
 535         return 0;
 536 }
 537
 538
 539 struct flash_block {
 540         stm32_addr_t addr;
 541         unsigned     length;
 542         uint8_t*     data;
 543
 544         struct flash_block* next;
 545 };
 546
 547 static struct flash_block* flash_root;
 548
 549 static int flash_add_block(stm32_addr_t addr, unsigned length,
 550                            stlink_t *sl) {
 551         if(addr < FLASH_BASE || addr + length > FLASH_BASE + FLASH_SIZE) {
 552                 fprintf(stderr, "flash_add_block: incorrect bounds\n");
 553                 return -1;
 554         }
 555
 556         if(addr % FLASH_PAGE != 0 || length % FLASH_PAGE != 0) {
 557                 fprintf(stderr, "flash_add_block: unaligned block\n");
 558                 return -1;
 559         }
 560
 561         struct flash_block* new = malloc(sizeof(struct flash_block));
 562         new->next = flash_root;
 563
 564         new->addr   = addr;
 565         new->length = length;
 566         new->data   = calloc(length, 1);
 567
 568         flash_root = new;
 569
 570         return 0;
 571 }
 572
 573 static int flash_populate(stm32_addr_t addr, uint8_t* data, unsigned length) {
 574         int fit_blocks = 0, fit_length = 0;
 575
 576         for(struct flash_block* fb = flash_root; fb; fb = fb->next) {
 577                 /* Block: ------X------Y--------
 578                  * Data:            a-----b
 579                  *                a--b
 580                  *            a-----------b
 581                  * Block intersects with data, if:
 582                  *  a < Y && b > x
 583                  */
 584
 585                 unsigned X = fb->addr, Y = fb->addr + fb->length;
 586                 unsigned a = addr, b = addr + length;
 587                 if(a < Y && b > X) {
 588                         // from start of the block
 589                         unsigned start = (a > X ? a : X) - X;
 590                         unsigned end   = (b > Y ? Y : b) - X;
 591
 592                         memcpy(fb->data + start, data, end - start);
 593
 594                         fit_blocks++;
 595                         fit_length += end - start;
 596                 }
 597         }
 598
 599         if(fit_blocks == 0) {
 600                 fprintf(stderr, "Unfit data block %08x -> %04x\n", addr, length);
 601                 return -1;
 602         }
 603
 604         if(fit_length != length) {
 605                 fprintf(stderr, "warning: data block %08x -> %04x truncated to %04x\n",
 606                         addr, length, fit_length);
 607                 fprintf(stderr, "(this is not an error, just a GDB glitch)\n");
 608         }
 609
 610         return 0;
 611 }
 612
 613 static int flash_go(stlink_t *sl) {
 614         int error = -1;
 615
 616         // Some kinds of clock settings do not allow writing to flash.
 617         stlink_reset(sl);
 618
 619         for(struct flash_block* fb = flash_root; fb; fb = fb->next) {
 620                 #ifdef DEBUG
 621                 printf("flash_do: block %08x -> %04x\n", fb->addr, fb->length);
 622                 #endif
 623
 624                 unsigned length = fb->length;
 625                 for(stm32_addr_t page = fb->addr; page < fb->addr + fb->length; page += FLASH_PAGE) {
 626                         #ifdef DEBUG
 627                         printf("flash_do: page %08x\n", page);
 628                         #endif
 629
 630                         stlink_erase_flash_page(sl, page);
 631
 632                         if(stlink_write_flash(sl, page, fb->data + (page - fb->addr),
 633                                         length > FLASH_PAGE ? FLASH_PAGE : length) < 0)
 634                                 goto error;
 635                 }
 636
 637         }
 638
 639         stlink_reset(sl);
 640
 641         error = 0;
 642
 643 error:
 644         for(struct flash_block* fb = flash_root, *next; fb; fb = next) {
 645                 next = fb->next;
 646                 free(fb->data);
 647                 free(fb);
 648         }
 649
 650         flash_root = NULL;
 651
 652         return error;
 653 }
 654
 655 int serve(stlink_t *sl, int port) {
 656         int sock = socket(AF_INET, SOCK_STREAM, 0);
 657         if(sock < 0) {
 658                 perror("socket");
 659                 return 1;
 660         }
 661
 662         unsigned int val = 1;
 663         setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
 664
 665         struct sockaddr_in serv_addr = {0};
 666         serv_addr.sin_family = AF_INET;
 667         serv_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
 668         serv_addr.sin_port = htons(port);
 669
 670         if(bind(sock, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0) {
 671                 perror("bind");
 672                 return 1;
 673         }
 674
 675         if(listen(sock, 5) < 0) {
 676                 perror("listen");
 677                 return 1;
 678         }
 679
 680         stlink_force_debug(sl);
 681         stlink_reset(sl);
 682         init_code_breakpoints(sl);
 683         init_data_watchpoints(sl);
 684
 685         printf("Listening at *:%d...\n", port);
 686
 687         int client = accept(sock, NULL, NULL);
 688         signal (SIGINT, SIG_DFL);
 689         if(client < 0) {
 690                 perror("accept");
 691                 return 1;
 692         }
 693
 694         close(sock);
 695
 696         printf("GDB connected.\n");
 697
 698         /*
 699          * To allow resetting the chip from GDB it is required to
 700          * emulate attaching and detaching to target.
 701          */
 702         unsigned int attached = 1;
 703
 704         while(1) {
 705                 char* packet;
 706
 707                 int status = gdb_recv_packet(client, &packet);
 708                 if(status < 0) {
 709                         fprintf(stderr, "cannot recv: %d\n", status);
 710                         return 1;
 711                 }
 712
 713                 #ifdef DEBUG
 714                 printf("recv: %s\n", packet);
 715                 #endif
 716
 717                 char* reply = NULL;
 718                 reg regp;
 719
 720                 switch(packet[0]) {
 721                 case 'q': {
 722                         if(packet[1] == 'P' || packet[1] == 'C' || packet[1] == 'L') {
 723                                 reply = strdup("");
 724                                 break;
 725                         }
 726
 727                         char *separator = strstr(packet, ":"), *params = "";
 728                         if(separator == NULL) {
 729                                 separator = packet + strlen(packet);
 730                         } else {
 731                                 params = separator + 1;
 732                         }
 733
 734                         unsigned queryNameLength = (separator - &packet[1]);
 735                         char* queryName = calloc(queryNameLength + 1, 1);
 736                         strncpy(queryName, &packet[1], queryNameLength);
 737
 738                         #ifdef DEBUG
 739                         printf("query: %s;%s\n", queryName, params);
 740                         #endif
 741
 742                         if(!strcmp(queryName, "Supported")) {
 743                                 reply = strdup("PacketSize=3fff;qXfer:memory-map:read+");
 744                         } else if(!strcmp(queryName, "Xfer")) {
 745                                 char *type, *op, *s_addr, *s_length;
 746                                 char *tok = params;
 747                                 char *annex __attribute__((unused));
 748
 749                                 type     = strsep(&tok, ":");
 750                                 op       = strsep(&tok, ":");
 751                                 annex    = strsep(&tok, ":");
 752                                 s_addr   = strsep(&tok, ",");
 753                                 s_length = tok;
 754
 755                                 unsigned addr = strtoul(s_addr, NULL, 16),
 756                                        length = strtoul(s_length, NULL, 16);
 757
 758                                 #ifdef DEBUG
 759                                 printf("Xfer: type:%s;op:%s;annex:%s;addr:%d;length:%d\n",
 760                                         type, op, annex, addr, length);
 761                                 #endif
 762
 763                                 const char* data = NULL;
 764
 765                                 if(!strcmp(type, "memory-map") && !strcmp(op, "read"))
 766                                         data = current_memory_map;
 767
 768                                 if(data) {
 769                                         unsigned data_length = strlen(data);
 770                                         if(addr + length > data_length)
 771                                                 length = data_length - addr;
 772
 773                                         if(length == 0) {
 774                                                 reply = strdup("l");
 775                                         } else {
 776                                                 reply = calloc(length + 2, 1);
 777                                                 reply[0] = 'm';
 778                                                 strncpy(&reply[1], data, length);
 779                                         }
 780                                 }
 781                         }
 782
 783                         if(reply == NULL)
 784                                 reply = strdup("");
 785
 786                         free(queryName);
 787
 788                         break;
 789                 }
 790
 791                 case 'v': {
 792                         char *params = NULL;
 793                         char *cmdName = strtok_r(packet, ":;", &params);
 794
 795                         cmdName++; // vCommand -> Command
 796
 797                         if(!strcmp(cmdName, "FlashErase")) {
 798                                 char *s_addr, *s_length;
 799                                 char *tok = params;
 800
 801                                 s_addr   = strsep(&tok, ",");
 802                                 s_length = tok;
 803
 804                                 unsigned addr = strtoul(s_addr, NULL, 16),
 805                                        length = strtoul(s_length, NULL, 16);
 806
 807                                 #ifdef DEBUG
 808                                 printf("FlashErase: addr:%08x,len:%04x\n",
 809                                         addr, length);
 810                                 #endif
 811
 812                                 if(flash_add_block(addr, length, sl) < 0) {
 813                                         reply = strdup("E00");
 814                                 } else {
 815                                         reply = strdup("OK");
 816                                 }
 817                         } else if(!strcmp(cmdName, "FlashWrite")) {
 818                                 char *s_addr, *data;
 819                                 char *tok = params;
 820
 821                                 s_addr = strsep(&tok, ":");
 822                                 data   = tok;
 823
 824                                 unsigned addr = strtoul(s_addr, NULL, 16);
 825                                 unsigned data_length = status - (data - packet);
 826
 827                                 // Length of decoded data cannot be more than
 828                                 // encoded, as escapes are removed.
 829                                 // Additional byte is reserved for alignment fix.
 830                                 uint8_t *decoded = calloc(data_length + 1, 1);
 831                                 unsigned dec_index = 0;
 832                                 for(int i = 0; i < data_length; i++) {
 833                                         if(data[i] == 0x7d) {
 834                                                 i++;
 835                                                 decoded[dec_index++] = data[i] ^ 0x20;
 836                                         } else {
 837                                                 decoded[dec_index++] = data[i];
 838                                         }
 839                                 }
 840
 841                                 // Fix alignment
 842                                 if(dec_index % 2 != 0)
 843                                         dec_index++;
 844
 845                                 #ifdef DEBUG
 846                                 printf("binary packet %d -> %d\n", data_length, dec_index);
 847                                 #endif
 848
 849                                 if(flash_populate(addr, decoded, dec_index) < 0) {
 850                                         reply = strdup("E00");
 851                                 } else {
 852                                         reply = strdup("OK");
 853                                 }
 854                         } else if(!strcmp(cmdName, "FlashDone")) {
 855                                 if(flash_go(sl) < 0) {
 856                                         reply = strdup("E00");
 857                                 } else {
 858                                         reply = strdup("OK");
 859                                 }
 860                         } else if(!strcmp(cmdName, "Kill")) {
 861                                 attached = 0;
 862
 863                                 reply = strdup("OK");
 864                         }
 865
 866                         if(reply == NULL)
 867                                 reply = strdup("");
 868
 869                         break;
 870                 }
 871
 872                 case 'c':
 873                         stlink_run(sl);
 874
 875                         while(1) {
 876                                 int status = gdb_check_for_interrupt(client);
 877                                 if(status < 0) {
 878                                         fprintf(stderr, "cannot check for int: %d\n", status);
 879                                         return 1;
 880                                 }
 881
 882                                 if(status == 1) {
 883                                         stlink_force_debug(sl);
 884                                         break;
 885                                 }
 886
 887                                 stlink_status(sl);
 888                                 if(sl->core_stat == STLINK_CORE_HALTED) {
 889                                         break;
 890                                 }
 891
 892                                 usleep(100000);
 893                         }
 894
 895                         reply = strdup("S05"); // TRAP
 896                         break;
 897
 898                 case 's':
 899                         stlink_step(sl);
 900
 901                         reply = strdup("S05"); // TRAP
 902                         break;
 903
 904                 case '?':
 905                         if(attached) {
 906                                 reply = strdup("S05"); // TRAP
 907                         } else {
 908                                 /* Stub shall reply OK if not attached. */
 909                                 reply = strdup("OK");
 910                         }
 911                         break;
 912
 913                 case 'g':
 914                         stlink_read_all_regs(sl, &regp);
 915
 916                         reply = calloc(8 * 16 + 1, 1);
 917                         for(int i = 0; i < 16; i++)
 918                                 sprintf(&reply[i * 8], "%08x", htonl(regp.r[i]));
 919
 920                         break;
 921
 922                 case 'p': {
 923                         unsigned id = strtoul(&packet[1], NULL, 16);
 924                         unsigned myreg = 0xDEADDEAD;
 925
 926                         if(id < 16) {
 927                                 stlink_read_reg(sl, id, &regp);
 928                                 myreg = htonl(regp.r[id]);
 929                         } else if(id == 0x19) {
 930                                 stlink_read_reg(sl, 16, &regp);
 931                                 myreg = htonl(regp.xpsr);
 932                         } else {
 933                                 reply = strdup("E00");
 934                         }
 935
 936                         reply = calloc(8 + 1, 1);
 937                         sprintf(reply, "%08x", myreg);
 938
 939                         break;
 940                 }
 941
 942                 case 'P': {
 943                         char* s_reg = &packet[1];
 944                         char* s_value = strstr(&packet[1], "=") + 1;
 945
 946                         unsigned reg   = strtoul(s_reg,   NULL, 16);
 947                         unsigned value = strtoul(s_value, NULL, 16);
 948
 949                         if(reg < 16) {
 950                                 stlink_write_reg(sl, ntohl(value), reg);
 951                         } else if(reg == 0x19) {
 952                                 stlink_write_reg(sl, ntohl(value), 16);
 953                         } else {
 954                                 reply = strdup("E00");
 955                         }
 956
 957                         if(!reply) {
 958                                 reply = strdup("OK");
 959                         }
 960
 961                         break;
 962                 }
 963
 964                 case 'G':
 965                         for(int i = 0; i < 16; i++) {
 966                                 char str[9] = {0};
 967                                 strncpy(str, &packet[1 + i * 8], 8);
 968                                 uint32_t reg = strtoul(str, NULL, 16);
 969                                 stlink_write_reg(sl, ntohl(reg), i);
 970                         }
 971
 972                         reply = strdup("OK");
 973                         break;
 974
 975                 case 'm': {
 976                         char* s_start = &packet[1];
 977                         char* s_count = strstr(&packet[1], ",") + 1;
 978
 979                         stm32_addr_t start = strtoul(s_start, NULL, 16);
 980                         unsigned     count = strtoul(s_count, NULL, 16);
 981
 982                         unsigned adj_start = start % 4;
 983
 984                         stlink_read_mem32(sl, start - adj_start, (count % 4 == 0) ?
 985                                                 count : count + 4 - (count % 4));
 986
 987                         reply = calloc(count * 2 + 1, 1);
 988                         for(int i = 0; i < count; i++) {
 989                                 reply[i * 2 + 0] = hex[sl->q_buf[i + adj_start] >> 4];
 990                                 reply[i * 2 + 1] = hex[sl->q_buf[i + adj_start] & 0xf];
 991                         }
 992
 993                         break;
 994                 }
 995
 996                 case 'M': {
 997                         char* s_start = &packet[1];
 998                         char* s_count = strstr(&packet[1], ",") + 1;
 999                         char* hexdata = strstr(packet, ":") + 1;
1000
1001                         stm32_addr_t start = strtoul(s_start, NULL, 16);
1002                         unsigned     count = strtoul(s_count, NULL, 16);
1003
1004                         for(int i = 0; i < count; i ++) {
1005                                 char hex[3] = { hexdata[i*2], hexdata[i*2+1], 0 };
1006                                 uint8_t byte = strtoul(hex, NULL, 16);
1007                                 sl->q_buf[i] = byte;
1008                         }
1009
1010                         if((count % 4) == 0 && (start % 4) == 0) {
1011                                 stlink_write_mem32(sl, start, count);
1012                         } else {
1013                                 stlink_write_mem8(sl, start, count);
1014                         }
1015
1016                         reply = strdup("OK");
1017
1018                         break;
1019                 }
1020
1021                 case 'Z': {
1022                         char *endptr;
1023                         stm32_addr_t addr = strtoul(&packet[3], &endptr, 16);
1024                         stm32_addr_t len  = strtoul(&endptr[1], NULL, 16);
1025
1026                         switch (packet[1]) {
1027                                 case '1':
1028                                 if(update_code_breakpoint(sl, addr, 1) < 0) {
1029                                         reply = strdup("E00");
1030                                 } else {
1031                                         reply = strdup("OK");
1032                                 }
1033                                 break;
1034
1035                                 case '2':   // insert write watchpoint
1036                                 case '3':   // insert read  watchpoint
1037                                 case '4':   // insert access watchpoint
1038                                 {
1039                                         enum watchfun wf;
1040                                         if(packet[1] == '2') {
1041                                                 wf = WATCHWRITE;
1042                                         } else if(packet[1] == '3') {
1043                                                 wf = WATCHREAD;
1044                                         } else {
1045                                                 wf = WATCHACCESS;
1046                                                 if(add_data_watchpoint(sl, wf, addr, len) < 0) {
1047                                                         reply = strdup("E00");
1048                                                 } else {
1049                                                         reply = strdup("OK");
1050                                                         break;
1051                                                 }
1052                                         }
1053                                 }
1054
1055                                 default:
1056                                 reply = strdup("");
1057                         }
1058                         break;
1059                 }
1060                 case 'z': {
1061                         char *endptr;
1062                         stm32_addr_t addr = strtoul(&packet[3], &endptr, 16);
1063                         //stm32_addr_t len  = strtoul(&endptr[1], NULL, 16);
1064
1065                         switch (packet[1]) {
1066                                 case '1': // remove breakpoint
1067                                 update_code_breakpoint(sl, addr, 0);
1068                                 reply = strdup("OK");
1069                                 break;
1070
1071                                 case '2' : // remove write watchpoint
1072                                 case '3' : // remove read watchpoint
1073                                 case '4' : // remove access watchpoint
1074                                 if(delete_data_watchpoint(sl, addr) < 0) {
1075                                         reply = strdup("E00");
1076                                 } else {
1077                                         reply = strdup("OK");
1078                                         break;
1079                                 }
1080
1081                                 default:
1082                                 reply = strdup("");
1083                         }
1084                         break;
1085                 }
1086
1087                 case '!': {
1088                         /*
1089                          * Enter extended mode which allows restarting.
1090                          * We do support that always.
1091                          */
1092
1093                         reply = strdup("OK");
1094
1095                         break;
1096                 }
1097
1098                 case 'R': {
1099                         /* Reset the core. */
1100
1101                         stlink_reset(sl);
1102                         init_code_breakpoints(sl);
1103                         init_data_watchpoints(sl);
1104
1105                         attached = 1;
1106
1107                         reply = strdup("OK");
1108
1109                         break;
1110                 }
1111
1112                 default:
1113                         reply = strdup("");
1114                 }
1115
1116                 if(reply) {
1117                         #ifdef DEBUG
1118                         printf("send: %s\n", reply);
1119                         #endif
1120
1121                         int result = gdb_send_packet(client, reply);
1122                         if(result != 0) {
1123                                 fprintf(stderr, "cannot send: %d\n", result);
1124                                 return 1;
1125                         }
1126
1127                         free(reply);
1128                 }
1129
1130                 free(packet);
1131         }
1132
1133         return 0;
1134 }