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 10
  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 = 10;
 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 (CONFIG_USE_LIBSG == 1)
 201                 if (strlen(state.devicename) == 0) {
 202                         const int DevNumMax = 99;
 203                         int ExistDevCount = 0;
 204
 205                         for (int DevNum = 0; DevNum <= DevNumMax; DevNum++) {
 206                                 if (DevNum < 10) {
 207                                         char DevName[] = "/dev/sgX";
 208                                         const int X_index = 7;
 209                                         DevName[X_index] = DevNum + '0';
 210                                         if (!access(DevName, F_OK)) {
 211                                                 sl = stlink_quirk_open(DevName, 0);
 212                                                 ExistDevCount++;
 213                                         }
 214                                 } else if (DevNum < 100) {
 215                                         char DevName[] = "/dev/sgXY";
 216                                         const int X_index = 7;
 217                                         const int Y_index = 8;
 218                                         DevName[X_index] = DevNum / 10 + '0';
 219                                         DevName[Y_index] = DevNum % 10 + '0';
 220                                         if (!access(DevName, F_OK)) {
 221                                                 sl = stlink_quirk_open(DevName, 0);
 222                                                 ExistDevCount++;
 223                                         }
 224                                 }
 225                                 if (sl != NULL) break;
 226                         }
 227
 228                         if (sl == NULL) {
 229                                 fprintf(stdout, "\nNumber of /dev/sgX devices found: %i \n",
 230                                         ExistDevCount);
 231                                 fprintf(stderr, "ST-LINK not found\n");
 232                                 return 1;
 233                         }
 234                 } else {
 235                         sl = stlink_quirk_open(state.devicename, state.logging_level);
 236                 }
 237                 break;
 238 #else
 239                 fprintf(stderr, "Support for stlink v1 disabled at build time...\n");
 240                 fprintf(stderr, "Perhaps you're on OSX, and we haven't finished removing the libsg deps?\n");
 241                 exit(EXIT_FAILURE);
 242 #endif
 243         }
 244
 245         if (stlink_current_mode(sl) == STLINK_DEV_DFU_MODE) {
 246                 stlink_exit_dfu_mode(sl);
 247         }
 248
 249         if(stlink_current_mode(sl) != STLINK_DEV_DEBUG_MODE) {
 250           stlink_enter_swd_mode(sl);
 251         }
 252
 253         uint32_t chip_id = stlink_chip_id(sl);
 254         uint32_t core_id = stlink_core_id(sl);
 255
 256         /* Fix chip_id for F4 */
 257         if (((chip_id & 0xFFF) == 0x411) && (core_id == CORE_M4_R0)) {
 258           printf("Fixing wrong chip_id for STM32F4 Rev A errata\n");
 259           chip_id = 0x413;
 260         }
 261
 262         printf("Chip ID is %08x, Core ID is  %08x.\n", chip_id, core_id);
 263
 264         const struct chip_params* params = NULL;
 265
 266         for(int i = 0; i < sizeof(devices) / sizeof(devices[0]); i++) {
 267                 if(devices[i].chip_id == (chip_id & 0xFFF)) {
 268                         params = &devices[i];
 269                         break;
 270                 }
 271         }
 272
 273         if(params == NULL) {
 274                 fprintf(stderr, "Cannot recognize the connected device!\n");
 275                 return 0;
 276         }
 277
 278         printf("Device connected: %s\n", params->description);
 279         printf("Device parameters: SRAM: 0x%x bytes, Flash: up to 0x%x bytes in pages of 0x%x bytes\n",
 280                 params->sram_size, params->max_flash_size, params->flash_pagesize);
 281
 282         FLASH_PAGE = params->flash_pagesize;
 283
 284         uint32_t flash_size;
 285
 286         stlink_read_mem32(sl, params->flash_size_reg, 4);
 287         flash_size = sl->q_buf[0] | (sl->q_buf[1] << 8);
 288
 289         printf("Flash size is %d KiB.\n", flash_size);
 290         // memory map is in 1k blocks.
 291         current_memory_map = make_memory_map(params, flash_size * 0x400);
 292
 293         while(serve(sl, state.listen_port) == 0);
 294
 295         /* Switch back to mass storage mode before closing. */
 296         stlink_run(sl);
 297         stlink_exit_debug_mode(sl);
 298         stlink_close(sl);
 299
 300         return 0;
 301 }
 302
 303 static const char* const memory_map_template =
 304   "<?xml version=\"1.0\"?>"
 305   "<!DOCTYPE memory-map PUBLIC \"+//IDN gnu.org//DTD GDB Memory Map V1.0//EN\""
 306   "     \"http://sourceware.org/gdb/gdb-memory-map.dtd\">"
 307   "<memory-map>"
 308   "  <memory type=\"rom\" start=\"0x00000000\" length=\"0x%x\"/>"       // code = sram, bootrom or flash; flash is bigger
 309   "  <memory type=\"ram\" start=\"0x20000000\" length=\"0x%x\"/>"       // sram 8k
 310   "  <memory type=\"flash\" start=\"0x08000000\" length=\"0x%x\">"
 311   "    <property name=\"blocksize\">0x%x</property>"
 312   "  </memory>"
 313   "  <memory type=\"ram\" start=\"0x40000000\" length=\"0x1fffffff\"/>" // peripheral regs
 314   "  <memory type=\"ram\" start=\"0xe0000000\" length=\"0x1fffffff\"/>" // cortex regs
 315   "  <memory type=\"rom\" start=\"0x%08x\" length=\"0x%x\"/>"           // bootrom
 316   "  <memory type=\"rom\" start=\"0x1ffff800\" length=\"0x8\"/>"        // option byte area
 317   "</memory-map>";
 318
 319 char* make_memory_map(const struct chip_params *params, uint32_t flash_size) {
 320         /* This will be freed in serve() */
 321         char* map = malloc(4096);
 322         map[0] = '\0';
 323
 324         snprintf(map, 4096, memory_map_template,
 325                         flash_size,
 326                         params->sram_size,
 327                         flash_size, params->flash_pagesize,
 328                         params->bootrom_base, params->bootrom_size);
 329
 330         return map;
 331 }
 332
 333
 334 /*
 335  * DWT_COMP0     0xE0001020
 336  * DWT_MASK0     0xE0001024
 337  * DWT_FUNCTION0 0xE0001028
 338  * DWT_COMP1     0xE0001030
 339  * DWT_MASK1     0xE0001034
 340  * DWT_FUNCTION1 0xE0001038
 341  * DWT_COMP2     0xE0001040
 342  * DWT_MASK2     0xE0001044
 343  * DWT_FUNCTION2 0xE0001048
 344  * DWT_COMP3     0xE0001050
 345  * DWT_MASK3     0xE0001054
 346  * DWT_FUNCTION3 0xE0001058
 347  */
 348
 349 #define DATA_WATCH_NUM 4
 350
 351 enum watchfun { WATCHDISABLED = 0, WATCHREAD = 5, WATCHWRITE = 6, WATCHACCESS = 7 };
 352
 353 struct code_hw_watchpoint {
 354         stm32_addr_t addr;
 355         uint8_t mask;
 356         enum watchfun fun;
 357 };
 358
 359 struct code_hw_watchpoint data_watches[DATA_WATCH_NUM];
 360
 361 static void init_data_watchpoints(stlink_t *sl) {
 362         #ifdef DEBUG
 363         printf("init watchpoints\n");
 364         #endif
 365
 366         // set trcena in debug command to turn on dwt unit
 367         stlink_read_mem32(sl, 0xE000EDFC, 4);
 368         sl->q_buf[3] |= 1;
 369         stlink_write_mem32(sl, 0xE000EDFC, 4);
 370
 371         // make sure all watchpoints are cleared
 372         memset(sl->q_buf, 0, 4);
 373         for(int i = 0; i < DATA_WATCH_NUM; i++) {
 374                 data_watches[i].fun = WATCHDISABLED;
 375                 stlink_write_mem32(sl, 0xe0001028 + i * 16, 4);
 376         }
 377 }
 378
 379 static int add_data_watchpoint(stlink_t *sl, enum watchfun wf, stm32_addr_t addr, unsigned int len)
 380 {
 381         int i = 0;
 382         uint32_t mask;
 383
 384         // computer mask
 385         // find a free watchpoint
 386         // configure
 387
 388         mask = -1;
 389         i = len;
 390         while(i) {
 391                 i >>= 1;
 392                 mask++;
 393         }
 394
 395         if((mask != -1) && (mask < 16)) {
 396                 for(i = 0; i < DATA_WATCH_NUM; i++) {
 397                         // is this an empty slot ?
 398                         if(data_watches[i].fun == WATCHDISABLED) {
 399                                 #ifdef DEBUG
 400                                 printf("insert watchpoint %d addr %x wf %u mask %u len %d\n", i, addr, wf, mask, len);
 401                                 #endif
 402
 403                                 data_watches[i].fun = wf;
 404                                 data_watches[i].addr = addr;
 405                                 data_watches[i].mask = mask;
 406
 407                                 // insert comparator address
 408                                 sl->q_buf[0] = (addr & 0xff);
 409                                 sl->q_buf[1] = ((addr >> 8) & 0xff);
 410                                 sl->q_buf[2] = ((addr >> 16) & 0xff);
 411                                 sl->q_buf[3] = ((addr >> 24)  & 0xff);
 412
 413                                 stlink_write_mem32(sl, 0xE0001020 + i * 16, 4);
 414
 415                                 // insert mask
 416                                 memset(sl->q_buf, 0, 4);
 417                                 sl->q_buf[0] = mask;
 418                                 stlink_write_mem32(sl, 0xE0001024 + i * 16, 4);
 419
 420                                 // insert function
 421                                 memset(sl->q_buf, 0, 4);
 422                                 sl->q_buf[0] = wf;
 423                                 stlink_write_mem32(sl, 0xE0001028 + i * 16, 4);
 424
 425                                 // just to make sure the matched bit is clear !
 426                                 stlink_read_mem32(sl,  0xE0001028 + i * 16, 4);
 427                                 return 0;
 428                         }
 429                 }
 430         }
 431
 432         #ifdef DEBUG
 433         printf("failure: add watchpoints addr %x wf %u len %u\n", addr, wf, len);
 434         #endif
 435         return -1;
 436 }
 437
 438 static int delete_data_watchpoint(stlink_t *sl, stm32_addr_t addr)
 439 {
 440         int i;
 441
 442         for(i = 0 ; i < DATA_WATCH_NUM; i++) {
 443                 if((data_watches[i].addr == addr) && (data_watches[i].fun != WATCHDISABLED)) {
 444                         #ifdef DEBUG
 445                         printf("delete watchpoint %d addr %x\n", i, addr);
 446                         #endif
 447
 448                         memset(sl->q_buf, 0, 4);
 449                         data_watches[i].fun = WATCHDISABLED;
 450                         stlink_write_mem32(sl, 0xe0001028 + i * 16, 4);
 451
 452                         return 0;
 453                 }
 454         }
 455
 456         #ifdef DEBUG
 457         printf("failure: delete watchpoint addr %x\n", addr);
 458         #endif
 459
 460         return -1;
 461 }
 462
 463 #define CODE_BREAK_NUM  6
 464 #define CODE_BREAK_LOW  0x01
 465 #define CODE_BREAK_HIGH 0x02
 466
 467 struct code_hw_breakpoint {
 468         stm32_addr_t addr;
 469         int          type;
 470 };
 471
 472 struct code_hw_breakpoint code_breaks[CODE_BREAK_NUM];
 473
 474 static void init_code_breakpoints(stlink_t *sl) {
 475         memset(sl->q_buf, 0, 4);
 476         sl->q_buf[0] = 0x03; // KEY | ENABLE
 477         stlink_write_mem32(sl, CM3_REG_FP_CTRL, 4);
 478         printf("KARL - should read back as 0x03, not 60 02 00 00\n");
 479         stlink_read_mem32(sl, CM3_REG_FP_CTRL, 4);
 480
 481         memset(sl->q_buf, 0, 4);
 482         for(int i = 0; i < CODE_BREAK_NUM; i++) {
 483                 code_breaks[i].type = 0;
 484                 stlink_write_mem32(sl, CM3_REG_FP_COMP0 + i * 4, 4);
 485         }
 486 }
 487
 488 static int update_code_breakpoint(stlink_t *sl, stm32_addr_t addr, int set) {
 489         stm32_addr_t fpb_addr = addr & ~0x3;
 490         int type = addr & 0x2 ? CODE_BREAK_HIGH : CODE_BREAK_LOW;
 491
 492         if(addr & 1) {
 493                 fprintf(stderr, "update_code_breakpoint: unaligned address %08x\n", addr);
 494                 return -1;
 495         }
 496
 497         int id = -1;
 498         for(int i = 0; i < CODE_BREAK_NUM; i++) {
 499                 if(fpb_addr == code_breaks[i].addr ||
 500                         (set && code_breaks[i].type == 0)) {
 501                         id = i;
 502                         break;
 503                 }
 504         }
 505
 506         if(id == -1) {
 507                 if(set) return -1; // Free slot not found
 508                 else    return 0;  // Breakpoint is already removed
 509         }
 510
 511         struct code_hw_breakpoint* brk = &code_breaks[id];
 512
 513         brk->addr = fpb_addr;
 514
 515         if(set) brk->type |= type;
 516         else    brk->type &= ~type;
 517
 518         memset(sl->q_buf, 0, 4);
 519
 520         if(brk->type == 0) {
 521                 #ifdef DEBUG
 522                 printf("clearing hw break %d\n", id);
 523                 #endif
 524
 525                 stlink_write_mem32(sl, 0xe0002008 + id * 4, 4);
 526         } else {
 527                 sl->q_buf[0] = ( brk->addr        & 0xff) | 1;
 528                 sl->q_buf[1] = ((brk->addr >> 8)  & 0xff);
 529                 sl->q_buf[2] = ((brk->addr >> 16) & 0xff);
 530                 sl->q_buf[3] = ((brk->addr >> 24) & 0xff) | (brk->type << 6);
 531
 532                 #ifdef DEBUG
 533                 printf("setting hw break %d at %08x (%d)\n",
 534                         id, brk->addr, brk->type);
 535                 printf("reg %02x %02x %02x %02x\n",
 536                         sl->q_buf[3], sl->q_buf[2], sl->q_buf[1], sl->q_buf[0]);
 537                 #endif
 538
 539                 stlink_write_mem32(sl, 0xe0002008 + id * 4, 4);
 540         }
 541
 542         return 0;
 543 }
 544
 545
 546 struct flash_block {
 547         stm32_addr_t addr;
 548         unsigned     length;
 549         uint8_t*     data;
 550
 551         struct flash_block* next;
 552 };
 553
 554 static struct flash_block* flash_root;
 555
 556 static int flash_add_block(stm32_addr_t addr, unsigned length,
 557                            stlink_t *sl) {
 558         if(addr < FLASH_BASE || addr + length > FLASH_BASE + FLASH_SIZE) {
 559                 fprintf(stderr, "flash_add_block: incorrect bounds\n");
 560                 return -1;
 561         }
 562
 563         if(addr % FLASH_PAGE != 0 || length % FLASH_PAGE != 0) {
 564                 fprintf(stderr, "flash_add_block: unaligned block\n");
 565                 return -1;
 566         }
 567
 568         struct flash_block* new = malloc(sizeof(struct flash_block));
 569         new->next = flash_root;
 570
 571         new->addr   = addr;
 572         new->length = length;
 573         new->data   = calloc(length, 1);
 574
 575         flash_root = new;
 576
 577         return 0;
 578 }
 579
 580 static int flash_populate(stm32_addr_t addr, uint8_t* data, unsigned length) {
 581         int fit_blocks = 0, fit_length = 0;
 582
 583         for(struct flash_block* fb = flash_root; fb; fb = fb->next) {
 584                 /* Block: ------X------Y--------
 585                  * Data:            a-----b
 586                  *                a--b
 587                  *            a-----------b
 588                  * Block intersects with data, if:
 589                  *  a < Y && b > x
 590                  */
 591
 592                 unsigned X = fb->addr, Y = fb->addr + fb->length;
 593                 unsigned a = addr, b = addr + length;
 594                 if(a < Y && b > X) {
 595                         // from start of the block
 596                         unsigned start = (a > X ? a : X) - X;
 597                         unsigned end   = (b > Y ? Y : b) - X;
 598
 599                         memcpy(fb->data + start, data, end - start);
 600
 601                         fit_blocks++;
 602                         fit_length += end - start;
 603                 }
 604         }
 605
 606         if(fit_blocks == 0) {
 607                 fprintf(stderr, "Unfit data block %08x -> %04x\n", addr, length);
 608                 return -1;
 609         }
 610
 611         if(fit_length != length) {
 612                 fprintf(stderr, "warning: data block %08x -> %04x truncated to %04x\n",
 613                         addr, length, fit_length);
 614                 fprintf(stderr, "(this is not an error, just a GDB glitch)\n");
 615         }
 616
 617         return 0;
 618 }
 619
 620 static int flash_go(stlink_t *sl) {
 621         int error = -1;
 622
 623         // Some kinds of clock settings do not allow writing to flash.
 624         stlink_reset(sl);
 625
 626         for(struct flash_block* fb = flash_root; fb; fb = fb->next) {
 627                 #ifdef DEBUG
 628                 printf("flash_do: block %08x -> %04x\n", fb->addr, fb->length);
 629                 #endif
 630
 631                 unsigned length = fb->length;
 632                 for(stm32_addr_t page = fb->addr; page < fb->addr + fb->length; page += FLASH_PAGE) {
 633                         #ifdef DEBUG
 634                         printf("flash_do: page %08x\n", page);
 635                         #endif
 636
 637                         stlink_erase_flash_page(sl, page);
 638
 639                         if(stlink_write_flash(sl, page, fb->data + (page - fb->addr),
 640                                         length > FLASH_PAGE ? FLASH_PAGE : length) < 0)
 641                                 goto error;
 642                 }
 643
 644         }
 645
 646         stlink_reset(sl);
 647
 648         error = 0;
 649
 650 error:
 651         for(struct flash_block* fb = flash_root, *next; fb; fb = next) {
 652                 next = fb->next;
 653                 free(fb->data);
 654                 free(fb);
 655         }
 656
 657         flash_root = NULL;
 658
 659         return error;
 660 }
 661
 662 int serve(stlink_t *sl, int port) {
 663         int sock = socket(AF_INET, SOCK_STREAM, 0);
 664         if(sock < 0) {
 665                 perror("socket");
 666                 return 1;
 667         }
 668
 669         unsigned int val = 1;
 670         setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
 671
 672         struct sockaddr_in serv_addr = {0};
 673         serv_addr.sin_family = AF_INET;
 674         serv_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
 675         serv_addr.sin_port = htons(port);
 676
 677         if(bind(sock, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0) {
 678                 perror("bind");
 679                 return 1;
 680         }
 681
 682         if(listen(sock, 5) < 0) {
 683                 perror("listen");
 684                 return 1;
 685         }
 686
 687         stlink_force_debug(sl);
 688         stlink_reset(sl);
 689         init_code_breakpoints(sl);
 690         init_data_watchpoints(sl);
 691
 692         printf("Listening at *:%d...\n", port);
 693
 694         int client = accept(sock, NULL, NULL);
 695         signal (SIGINT, SIG_DFL);
 696         if(client < 0) {
 697                 perror("accept");
 698                 return 1;
 699         }
 700
 701         close(sock);
 702
 703         printf("GDB connected.\n");
 704
 705         /*
 706          * To allow resetting the chip from GDB it is required to
 707          * emulate attaching and detaching to target.
 708          */
 709         unsigned int attached = 1;
 710
 711         while(1) {
 712                 char* packet;
 713
 714                 int status = gdb_recv_packet(client, &packet);
 715                 if(status < 0) {
 716                         fprintf(stderr, "cannot recv: %d\n", status);
 717                         return 1;
 718                 }
 719
 720                 #ifdef DEBUG
 721                 printf("recv: %s\n", packet);
 722                 #endif
 723
 724                 char* reply = NULL;
 725                 reg regp;
 726
 727                 switch(packet[0]) {
 728                 case 'q': {
 729                         if(packet[1] == 'P' || packet[1] == 'C' || packet[1] == 'L') {
 730                                 reply = strdup("");
 731                                 break;
 732                         }
 733
 734                         char *separator = strstr(packet, ":"), *params = "";
 735                         if(separator == NULL) {
 736                                 separator = packet + strlen(packet);
 737                         } else {
 738                                 params = separator + 1;
 739                         }
 740
 741                         unsigned queryNameLength = (separator - &packet[1]);
 742                         char* queryName = calloc(queryNameLength + 1, 1);
 743                         strncpy(queryName, &packet[1], queryNameLength);
 744
 745                         #ifdef DEBUG
 746                         printf("query: %s;%s\n", queryName, params);
 747                         #endif
 748
 749                         if(!strcmp(queryName, "Supported")) {
 750                                 reply = strdup("PacketSize=3fff;qXfer:memory-map:read+");
 751                         } else if(!strcmp(queryName, "Xfer")) {
 752                                 char *type, *op, *s_addr, *s_length;
 753                                 char *tok = params;
 754                                 char *annex __attribute__((unused));
 755
 756                                 type     = strsep(&tok, ":");
 757                                 op       = strsep(&tok, ":");
 758                                 annex    = strsep(&tok, ":");
 759                                 s_addr   = strsep(&tok, ",");
 760                                 s_length = tok;
 761
 762                                 unsigned addr = strtoul(s_addr, NULL, 16),
 763                                        length = strtoul(s_length, NULL, 16);
 764
 765                                 #ifdef DEBUG
 766                                 printf("Xfer: type:%s;op:%s;annex:%s;addr:%d;length:%d\n",
 767                                         type, op, annex, addr, length);
 768                                 #endif
 769
 770                                 const char* data = NULL;
 771
 772                                 if(!strcmp(type, "memory-map") && !strcmp(op, "read"))
 773                                         data = current_memory_map;
 774
 775                                 if(data) {
 776                                         unsigned data_length = strlen(data);
 777                                         if(addr + length > data_length)
 778                                                 length = data_length - addr;
 779
 780                                         if(length == 0) {
 781                                                 reply = strdup("l");
 782                                         } else {
 783                                                 reply = calloc(length + 2, 1);
 784                                                 reply[0] = 'm';
 785                                                 strncpy(&reply[1], data, length);
 786                                         }
 787                                 }
 788                         }
 789
 790                         if(reply == NULL)
 791                                 reply = strdup("");
 792
 793                         free(queryName);
 794
 795                         break;
 796                 }
 797
 798                 case 'v': {
 799                         char *params = NULL;
 800                         char *cmdName = strtok_r(packet, ":;", &params);
 801
 802                         cmdName++; // vCommand -> Command
 803
 804                         if(!strcmp(cmdName, "FlashErase")) {
 805                                 char *s_addr, *s_length;
 806                                 char *tok = params;
 807
 808                                 s_addr   = strsep(&tok, ",");
 809                                 s_length = tok;
 810
 811                                 unsigned addr = strtoul(s_addr, NULL, 16),
 812                                        length = strtoul(s_length, NULL, 16);
 813
 814                                 #ifdef DEBUG
 815                                 printf("FlashErase: addr:%08x,len:%04x\n",
 816                                         addr, length);
 817                                 #endif
 818
 819                                 if(flash_add_block(addr, length, sl) < 0) {
 820                                         reply = strdup("E00");
 821                                 } else {
 822                                         reply = strdup("OK");
 823                                 }
 824                         } else if(!strcmp(cmdName, "FlashWrite")) {
 825                                 char *s_addr, *data;
 826                                 char *tok = params;
 827
 828                                 s_addr = strsep(&tok, ":");
 829                                 data   = tok;
 830
 831                                 unsigned addr = strtoul(s_addr, NULL, 16);
 832                                 unsigned data_length = status - (data - packet);
 833
 834                                 // Length of decoded data cannot be more than
 835                                 // encoded, as escapes are removed.
 836                                 // Additional byte is reserved for alignment fix.
 837                                 uint8_t *decoded = calloc(data_length + 1, 1);
 838                                 unsigned dec_index = 0;
 839                                 for(int i = 0; i < data_length; i++) {
 840                                         if(data[i] == 0x7d) {
 841                                                 i++;
 842                                                 decoded[dec_index++] = data[i] ^ 0x20;
 843                                         } else {
 844                                                 decoded[dec_index++] = data[i];
 845                                         }
 846                                 }
 847
 848                                 // Fix alignment
 849                                 if(dec_index % 2 != 0)
 850                                         dec_index++;
 851
 852                                 #ifdef DEBUG
 853                                 printf("binary packet %d -> %d\n", data_length, dec_index);
 854                                 #endif
 855
 856                                 if(flash_populate(addr, decoded, dec_index) < 0) {
 857                                         reply = strdup("E00");
 858                                 } else {
 859                                         reply = strdup("OK");
 860                                 }
 861                         } else if(!strcmp(cmdName, "FlashDone")) {
 862                                 if(flash_go(sl) < 0) {
 863                                         reply = strdup("E00");
 864                                 } else {
 865                                         reply = strdup("OK");
 866                                 }
 867                         } else if(!strcmp(cmdName, "Kill")) {
 868                                 attached = 0;
 869
 870                                 reply = strdup("OK");
 871                         }
 872
 873                         if(reply == NULL)
 874                                 reply = strdup("");
 875
 876                         break;
 877                 }
 878
 879                 case 'c':
 880                         stlink_run(sl);
 881
 882                         while(1) {
 883                                 int status = gdb_check_for_interrupt(client);
 884                                 if(status < 0) {
 885                                         fprintf(stderr, "cannot check for int: %d\n", status);
 886                                         return 1;
 887                                 }
 888
 889                                 if(status == 1) {
 890                                         stlink_force_debug(sl);
 891                                         break;
 892                                 }
 893
 894                                 stlink_status(sl);
 895                                 if(sl->core_stat == STLINK_CORE_HALTED) {
 896                                         break;
 897                                 }
 898
 899                                 usleep(100000);
 900                         }
 901
 902                         reply = strdup("S05"); // TRAP
 903                         break;
 904
 905                 case 's':
 906                         stlink_step(sl);
 907
 908                         reply = strdup("S05"); // TRAP
 909                         break;
 910
 911                 case '?':
 912                         if(attached) {
 913                                 reply = strdup("S05"); // TRAP
 914                         } else {
 915                                 /* Stub shall reply OK if not attached. */
 916                                 reply = strdup("OK");
 917                         }
 918                         break;
 919
 920                 case 'g':
 921                         stlink_read_all_regs(sl, &regp);
 922
 923                         reply = calloc(8 * 16 + 1, 1);
 924                         for(int i = 0; i < 16; i++)
 925                                 sprintf(&reply[i * 8], "%08x", htonl(regp.r[i]));
 926
 927                         break;
 928
 929                 case 'p': {
 930                         unsigned id = strtoul(&packet[1], NULL, 16);
 931                         unsigned myreg = 0xDEADDEAD;
 932
 933                         if(id < 16) {
 934                                 stlink_read_reg(sl, id, &regp);
 935                                 myreg = htonl(regp.r[id]);
 936                         } else if(id == 0x19) {
 937                                 stlink_read_reg(sl, 16, &regp);
 938                                 myreg = htonl(regp.xpsr);
 939                         } else {
 940                                 reply = strdup("E00");
 941                         }
 942
 943                         reply = calloc(8 + 1, 1);
 944                         sprintf(reply, "%08x", myreg);
 945
 946                         break;
 947                 }
 948
 949                 case 'P': {
 950                         char* s_reg = &packet[1];
 951                         char* s_value = strstr(&packet[1], "=") + 1;
 952
 953                         unsigned reg   = strtoul(s_reg,   NULL, 16);
 954                         unsigned value = strtoul(s_value, NULL, 16);
 955
 956                         if(reg < 16) {
 957                                 stlink_write_reg(sl, ntohl(value), reg);
 958                         } else if(reg == 0x19) {
 959                                 stlink_write_reg(sl, ntohl(value), 16);
 960                         } else {
 961                                 reply = strdup("E00");
 962                         }
 963
 964                         if(!reply) {
 965                                 reply = strdup("OK");
 966                         }
 967
 968                         break;
 969                 }
 970
 971                 case 'G':
 972                         for(int i = 0; i < 16; i++) {
 973                                 char str[9] = {0};
 974                                 strncpy(str, &packet[1 + i * 8], 8);
 975                                 uint32_t reg = strtoul(str, NULL, 16);
 976                                 stlink_write_reg(sl, ntohl(reg), i);
 977                         }
 978
 979                         reply = strdup("OK");
 980                         break;
 981
 982                 case 'm': {
 983                         char* s_start = &packet[1];
 984                         char* s_count = strstr(&packet[1], ",") + 1;
 985
 986                         stm32_addr_t start = strtoul(s_start, NULL, 16);
 987                         unsigned     count = strtoul(s_count, NULL, 16);
 988
 989                         unsigned adj_start = start % 4;
 990
 991                         stlink_read_mem32(sl, start - adj_start, (count % 4 == 0) ?
 992                                                 count : count + 4 - (count % 4));
 993
 994                         reply = calloc(count * 2 + 1, 1);
 995                         for(int i = 0; i < count; i++) {
 996                                 reply[i * 2 + 0] = hex[sl->q_buf[i + adj_start] >> 4];
 997                                 reply[i * 2 + 1] = hex[sl->q_buf[i + adj_start] & 0xf];
 998                         }
 999
1000                         break;
1001                 }
1002
1003                 case 'M': {
1004                         char* s_start = &packet[1];
1005                         char* s_count = strstr(&packet[1], ",") + 1;
1006                         char* hexdata = strstr(packet, ":") + 1;
1007
1008                         stm32_addr_t start = strtoul(s_start, NULL, 16);
1009                         unsigned     count = strtoul(s_count, NULL, 16);
1010
1011                         for(int i = 0; i < count; i ++) {
1012                                 char hex[3] = { hexdata[i*2], hexdata[i*2+1], 0 };
1013                                 uint8_t byte = strtoul(hex, NULL, 16);
1014                                 sl->q_buf[i] = byte;
1015                         }
1016
1017                         if((count % 4) == 0 && (start % 4) == 0) {
1018                                 stlink_write_mem32(sl, start, count);
1019                         } else {
1020                                 stlink_write_mem8(sl, start, count);
1021                         }
1022
1023                         reply = strdup("OK");
1024
1025                         break;
1026                 }
1027
1028                 case 'Z': {
1029                         char *endptr;
1030                         stm32_addr_t addr = strtoul(&packet[3], &endptr, 16);
1031                         stm32_addr_t len  = strtoul(&endptr[1], NULL, 16);
1032
1033                         switch (packet[1]) {
1034                                 case '1':
1035                                 if(update_code_breakpoint(sl, addr, 1) < 0) {
1036                                         reply = strdup("E00");
1037                                 } else {
1038                                         reply = strdup("OK");
1039                                 }
1040                                 break;
1041
1042                                 case '2':   // insert write watchpoint
1043                                 case '3':   // insert read  watchpoint
1044                                 case '4':   // insert access watchpoint
1045                                 {
1046                                         enum watchfun wf;
1047                                         if(packet[1] == '2') {
1048                                                 wf = WATCHWRITE;
1049                                         } else if(packet[1] == '3') {
1050                                                 wf = WATCHREAD;
1051                                         } else {
1052                                                 wf = WATCHACCESS;
1053                                                 if(add_data_watchpoint(sl, wf, addr, len) < 0) {
1054                                                         reply = strdup("E00");
1055                                                 } else {
1056                                                         reply = strdup("OK");
1057                                                         break;
1058                                                 }
1059                                         }
1060                                 }
1061
1062                                 default:
1063                                 reply = strdup("");
1064                         }
1065                         break;
1066                 }
1067                 case 'z': {
1068                         char *endptr;
1069                         stm32_addr_t addr = strtoul(&packet[3], &endptr, 16);
1070                         //stm32_addr_t len  = strtoul(&endptr[1], NULL, 16);
1071
1072                         switch (packet[1]) {
1073                                 case '1': // remove breakpoint
1074                                 update_code_breakpoint(sl, addr, 0);
1075                                 reply = strdup("OK");
1076                                 break;
1077
1078                                 case '2' : // remove write watchpoint
1079                                 case '3' : // remove read watchpoint
1080                                 case '4' : // remove access watchpoint
1081                                 if(delete_data_watchpoint(sl, addr) < 0) {
1082                                         reply = strdup("E00");
1083                                 } else {
1084                                         reply = strdup("OK");
1085                                         break;
1086                                 }
1087
1088                                 default:
1089                                 reply = strdup("");
1090                         }
1091                         break;
1092                 }
1093
1094                 case '!': {
1095                         /*
1096                          * Enter extended mode which allows restarting.
1097                          * We do support that always.
1098                          */
1099
1100                         reply = strdup("OK");
1101
1102                         break;
1103                 }
1104
1105                 case 'R': {
1106                         /* Reset the core. */
1107
1108                         stlink_reset(sl);
1109                         init_code_breakpoints(sl);
1110                         init_data_watchpoints(sl);
1111
1112                         attached = 1;
1113
1114                         reply = strdup("OK");
1115
1116                         break;
1117                 }
1118
1119                 default:
1120                         reply = strdup("");
1121                 }
1122
1123                 if(reply) {
1124                         #ifdef DEBUG
1125                         printf("send: %s\n", reply);
1126                         #endif
1127
1128                         int result = gdb_send_packet(client, reply);
1129                         if(result != 0) {
1130                                 fprintf(stderr, "cannot send: %d\n", result);
1131                                 return 1;
1132                         }
1133
1134                         free(reply);
1135                 }
1136
1137                 free(packet);
1138         }
1139
1140         return 0;
1141 }