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

   1 /* -*- tab-width:8 -*- */
   2
   3 /*
   4  Copyright (C)  2011 Peter Zotov <whitequark@whitequark.org>
   5  Use of this source code is governed by a BSD-style
   6  license that can be found in the LICENSE file.
   7 */
   8
   9 #include <stdio.h>
  10 #include <string.h>
  11 #include <stdlib.h>
  12 #include <unistd.h>
  13 #include <sys/types.h>
  14 #include <sys/socket.h>
  15 #include <netinet/in.h>
  16 #include <arpa/inet.h>
  17 #include "gdb-remote.h"
  18 #include "stlink-hw.h"
  19
  20 static const char hex[] = "0123456789abcdef";
  21
  22 // configured for STM32F100RB
  23 static const char* const c_memory_map =
  24   "<?xml version=\"1.0\"?>"
  25   "<!DOCTYPE memory-map PUBLIC \"+//IDN gnu.org//DTD GDB Memory Map V1.0//EN\""
  26   "     \"http://sourceware.org/gdb/gdb-memory-map.dtd\">"
  27   "<memory-map>"
  28   "  <memory type=\"rom\" start=\"0x00000000\" length=\"0x20000\"/>"    // code = sram or flash
  29   "  <memory type=\"ram\" start=\"0x20000000\" length=\"0x2000\"/>"     // sram 8k
  30   "  <memory type=\"flash\" start=\"0x08000000\" length=\"0x20000\">"   // flash 128k
  31   "    <property name=\"blocksize\">0x400</property>"                   // 1k pages
  32   "  </memory>"
  33   "  <memory type=\"ram\" start=\"0x40000000\" length=\"0x1fffffff\"/>" // peripheral regs
  34   "  <memory type=\"ram\" start=\"0xe0000000\" length=\"0x1fffffff\"/>" // cortex regs
  35   "</memory-map>";
  36
  37 int serve(struct stlink* sl, int port);
  38
  39 int main(int argc, char** argv) {
  40         if(argc != 3) {
  41                 fprintf(stderr, "Usage: %s <port> /dev/sgX\n", argv[0]);
  42                 return 1;
  43         }
  44
  45         struct stlink *sl = stlink_quirk_open(argv[2], 0);
  46         if (sl == NULL)
  47                 return 1;
  48
  49         if(stlink_current_mode(sl) != STLINK_DEV_DEBUG_MODE)
  50                 stlink_enter_swd_mode(sl);
  51
  52         stlink_core_id(sl);
  53         printf("Debugging ARM core %08x.\n", sl->core_id);
  54
  55         int port = atoi(argv[1]);
  56
  57         while(serve(sl, port) == 0);
  58
  59         stlink_close(sl);
  60
  61         return 0;
  62 }
  63
  64 #define CODE_BREAK_NUM  6
  65
  66 #define CODE_BREAK_LOW  0x01
  67 #define CODE_BREAK_HIGH 0x02
  68
  69 struct code_hw_breakpoint {
  70         stm32_addr_t addr;
  71         int          type;
  72 };
  73
  74 struct code_hw_breakpoint code_breaks[CODE_BREAK_NUM];
  75
  76 static void init_code_breakpoints(struct stlink* sl) {
  77         memset(sl->q_buf, 0, 4);
  78         sl->q_buf[0] = 0x03; // KEY | ENABLE
  79         stlink_write_mem32(sl, 0xe0002000, 4);
  80
  81         memset(sl->q_buf, 0, 4);
  82         for(int i = 0; i < CODE_BREAK_NUM; i++) {
  83                 code_breaks[i].type = 0;
  84                 stlink_write_mem32(sl, 0xe0002008 + i * 4, 4);
  85         }
  86 }
  87
  88 static int update_code_breakpoint(struct stlink* sl, stm32_addr_t addr, int set) {
  89         stm32_addr_t fpb_addr = addr & ~0x3;
  90         int type = addr & 0x2 ? CODE_BREAK_HIGH : CODE_BREAK_LOW;
  91
  92         if(addr & 1) {
  93                 fprintf(stderr, "update_code_breakpoint: unaligned address %08x\n", addr);
  94                 return -1;
  95         }
  96
  97         int id = -1;
  98         for(int i = 0; i < CODE_BREAK_NUM; i++) {
  99                 if(fpb_addr == code_breaks[i].addr ||
 100                         (set && code_breaks[i].type == 0)) {
 101                         id = i;
 102                         break;
 103                 }
 104         }
 105
 106         if(id == -1) {
 107                 if(set) return -1; // Free slot not found
 108                 else    return 0;  // Breakpoint is already removed
 109         }
 110
 111         struct code_hw_breakpoint* brk = &code_breaks[id];
 112
 113         brk->addr = fpb_addr;
 114
 115         if(set) brk->type |= type;
 116         else    brk->type &= ~type;
 117
 118         memset(sl->q_buf, 0, 4);
 119
 120         if(brk->type == 0) {
 121                 #ifdef DEBUG
 122                 printf("clearing hw break %d\n", id);
 123                 #endif
 124
 125                 stlink_write_mem32(sl, 0xe0002008 + id * 4, 4);
 126         } else {
 127                 sl->q_buf[0] = ( brk->addr        & 0xff) | 1;
 128                 sl->q_buf[1] = ((brk->addr >> 8)  & 0xff);
 129                 sl->q_buf[2] = ((brk->addr >> 16) & 0xff);
 130                 sl->q_buf[3] = ((brk->addr >> 24) & 0xff) | (brk->type << 6);
 131
 132                 #ifdef DEBUG
 133                 printf("setting hw break %d at %08x (%d)\n",
 134                         id, brk->addr, brk->type);
 135                 printf("reg %02x %02x %02x %02x\n",
 136                         sl->q_buf[3], sl->q_buf[2], sl->q_buf[1], sl->q_buf[0]);
 137                 #endif
 138
 139                 stlink_write_mem32(sl, 0xe0002008 + id * 4, 4);
 140         }
 141
 142         return 0;
 143 }
 144
 145 #define FLASH_BASE 0x08000000
 146 #define FLASH_PAGE 0x400
 147 #define FLASH_PAGE_MASK (~((1 << 10) - 1))
 148 #define FLASH_SIZE (FLASH_PAGE * 128)
 149
 150 struct flash_block {
 151         stm32_addr_t addr;
 152         unsigned     length;
 153         uint8_t*     data;
 154
 155         struct flash_block* next;
 156 };
 157
 158 static struct flash_block* flash_root;
 159
 160 static int flash_add_block(stm32_addr_t addr, unsigned length) {
 161         if(addr < FLASH_BASE || addr + length > FLASH_BASE + FLASH_SIZE) {
 162                 fprintf(stderr, "flash_add_block: incorrect bounds\n");
 163                 return -1;
 164         }
 165
 166         if(addr % FLASH_PAGE != 0 || length % FLASH_PAGE != 0) {
 167                 fprintf(stderr, "flash_add_block: unaligned block\n");
 168                 return -1;
 169         }
 170
 171         struct flash_block* new = malloc(sizeof(struct flash_block));
 172         new->next = flash_root;
 173
 174         new->addr   = addr;
 175         new->length = length;
 176         new->data   = calloc(length, 1);
 177
 178         flash_root = new;
 179
 180         return 0;
 181 }
 182
 183 static int flash_populate(stm32_addr_t addr, uint8_t* data, unsigned length) {
 184         int fit_blocks = 0, fit_length = 0;
 185
 186         for(struct flash_block* fb = flash_root; fb; fb = fb->next) {
 187                 /* Block: ------X------Y--------
 188                  * Data:            a-----b
 189                  *                a--b
 190                  *            a-----------b
 191                  * Block intersects with data, if:
 192                  *  a < Y && b > x
 193                  */
 194
 195                 unsigned X = fb->addr, Y = fb->addr + fb->length;
 196                 unsigned a = addr, b = addr + length;
 197                 if(a < Y && b > X) {
 198                         // from start of the block
 199                         unsigned start = (a > X ? a : X) - X;
 200                         unsigned end   = (b > Y ? Y : b) - X;
 201
 202                         memcpy(fb->data + start, data, end - start);
 203
 204                         fit_blocks++;
 205                         fit_length += end - start;
 206                 }
 207         }
 208
 209         if(fit_blocks == 0) {
 210                 fprintf(stderr, "Unfit data block %08x -> %04x\n", addr, length);
 211                 return -1;
 212         }
 213
 214         if(fit_length != length) {
 215                 fprintf(stderr, "warning: data block %08x -> %04x truncated to %04x\n",
 216                         addr, length, fit_length);
 217                 fprintf(stderr, "(this is not an error, just a GDB glitch)\n");
 218         }
 219
 220         return 0;
 221 }
 222
 223 static int flash_go(struct stlink* sl) {
 224         int error = -1;
 225
 226         // Some kinds of clock settings do not allow writing to flash.
 227         stlink_reset(sl);
 228
 229         for(struct flash_block* fb = flash_root; fb; fb = fb->next) {
 230                 #ifdef DEBUG
 231                 printf("flash_do: block %08x -> %04x\n", fb->addr, fb->length);
 232                 #endif
 233
 234                 unsigned length = fb->length;
 235                 for(stm32_addr_t page = fb->addr; page < fb->addr + fb->length; page += 0x400) {
 236                         #ifdef DEBUG
 237                         printf("flash_do: page %08x\n", page);
 238                         #endif
 239
 240                         stlink_erase_flash_page(sl, page);
 241
 242                         if(stlink_write_flash(sl, page, fb->data + (page - fb->addr),
 243                                         length > 0x400 ? 0x400 : length) < 0)
 244                                 goto error;
 245                 }
 246
 247         }
 248
 249         stlink_reset(sl);
 250
 251         error = 0;
 252
 253 error:
 254         for(struct flash_block* fb = flash_root, *next; fb; fb = next) {
 255                 next = fb->next;
 256                 free(fb->data);
 257                 free(fb);
 258         }
 259
 260         flash_root = NULL;
 261
 262         return error;
 263 }
 264
 265 int serve(struct stlink* sl, int port) {
 266         int sock = socket(AF_INET, SOCK_STREAM, 0);
 267         if(sock < 0) {
 268                 perror("socket");
 269                 return 1;
 270         }
 271
 272         unsigned int val = 1;
 273         setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
 274
 275         struct sockaddr_in serv_addr = {0};
 276         serv_addr.sin_family = AF_INET;
 277         serv_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
 278         serv_addr.sin_port = htons(port);
 279
 280         if(bind(sock, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0) {
 281                 perror("bind");
 282                 return 1;
 283         }
 284
 285         if(listen(sock, 5) < 0) {
 286                 perror("listen");
 287                 return 1;
 288         }
 289
 290         stlink_force_debug(sl);
 291         stlink_reset(sl);
 292         init_code_breakpoints(sl);
 293
 294         printf("Listening at *:%d...\n", port);
 295
 296         int client = accept(sock, NULL, NULL);
 297         if(client < 0) {
 298                 perror("accept");
 299                 return 1;
 300         }
 301
 302         close(sock);
 303
 304         printf("GDB connected.\n");
 305
 306         /*
 307          * To allow resetting the chip from GDB it is required to
 308          * emulate attaching and detaching to target.
 309          */
 310         unsigned int attached = 1;
 311
 312         while(1) {
 313                 char* packet;
 314
 315                 int status = gdb_recv_packet(client, &packet);
 316                 if(status < 0) {
 317                         fprintf(stderr, "cannot recv: %d\n", status);
 318                         return 1;
 319                 }
 320
 321                 #ifdef DEBUG
 322                 printf("recv: %s\n", packet);
 323                 #endif
 324
 325                 char* reply = NULL;
 326
 327                 switch(packet[0]) {
 328                 case 'q': {
 329                         if(packet[1] == 'P' || packet[1] == 'C' || packet[1] == 'L') {
 330                                 reply = strdup("");
 331                                 break;
 332                         }
 333
 334                         char *separator = strstr(packet, ":"), *params = "";
 335                         if(separator == NULL) {
 336                                 separator = packet + strlen(packet);
 337                         } else {
 338                                 params = separator + 1;
 339                         }
 340
 341                         unsigned queryNameLength = (separator - &packet[1]);
 342                         char* queryName = calloc(queryNameLength + 1, 1);
 343                         strncpy(queryName, &packet[1], queryNameLength);
 344
 345                         #ifdef DEBUG
 346                         printf("query: %s;%s\n", queryName, params);
 347                         #endif
 348
 349                         if(!strcmp(queryName, "Supported")) {
 350                                 reply = strdup("PacketSize=3fff;qXfer:memory-map:read+");
 351                         } else if(!strcmp(queryName, "Xfer")) {
 352                                 char *type, *op, *annex, *s_addr, *s_length;
 353                                 char *tok = params;
 354
 355                                 type     = strsep(&tok, ":");
 356                                 op       = strsep(&tok, ":");
 357                                 annex    = strsep(&tok, ":");
 358                                 s_addr   = strsep(&tok, ",");
 359                                 s_length = tok;
 360
 361                                 unsigned addr = strtoul(s_addr, NULL, 16),
 362                                        length = strtoul(s_length, NULL, 16);
 363
 364                                 #ifdef DEBUG
 365                                 printf("Xfer: type:%s;op:%s;annex:%s;addr:%d;length:%d\n",
 366                                         type, op, annex, addr, length);
 367                                 #endif
 368
 369                                 const char* data = NULL;
 370
 371                                 if(!strcmp(type, "memory-map") && !strcmp(op, "read"))
 372                                         data = c_memory_map;
 373
 374                                 if(data) {
 375                                         unsigned data_length = strlen(data);
 376                                         if(addr + length > data_length)
 377                                                 length = data_length - addr;
 378
 379                                         if(length == 0) {
 380                                                 reply = strdup("l");
 381                                         } else {
 382                                                 reply = calloc(length + 2, 1);
 383                                                 reply[0] = 'm';
 384                                                 strncpy(&reply[1], data, length);
 385                                         }
 386                                 }
 387                         }
 388
 389                         if(reply == NULL)
 390                                 reply = strdup("");
 391
 392                         free(queryName);
 393
 394                         break;
 395                 }
 396
 397                 case 'v': {
 398                         char *params = NULL;
 399                         char *cmdName = strtok_r(packet, ":;", &params);
 400
 401                         cmdName++; // vCommand -> Command
 402
 403                         if(!strcmp(cmdName, "FlashErase")) {
 404                                 char *s_addr, *s_length;
 405                                 char *tok = params;
 406
 407                                 s_addr   = strsep(&tok, ",");
 408                                 s_length = tok;
 409
 410                                 unsigned addr = strtoul(s_addr, NULL, 16),
 411                                        length = strtoul(s_length, NULL, 16);
 412
 413                                 #ifdef DEBUG
 414                                 printf("FlashErase: addr:%08x,len:%04x\n",
 415                                         addr, length);
 416                                 #endif
 417
 418                                 if(flash_add_block(addr, length) < 0) {
 419                                         reply = strdup("E00");
 420                                 } else {
 421                                         reply = strdup("OK");
 422                                 }
 423                         } else if(!strcmp(cmdName, "FlashWrite")) {
 424                                 char *s_addr, *data;
 425                                 char *tok = params;
 426
 427                                 s_addr = strsep(&tok, ":");
 428                                 data   = tok;
 429
 430                                 unsigned addr = strtoul(s_addr, NULL, 16);
 431                                 unsigned data_length = status - (data - packet);
 432
 433                                 // Length of decoded data cannot be more than
 434                                 // encoded, as escapes are removed.
 435                                 // Additional byte is reserved for alignment fix.
 436                                 uint8_t *decoded = calloc(data_length + 1, 1);
 437                                 unsigned dec_index = 0;
 438                                 for(int i = 0; i < data_length; i++) {
 439                                         if(data[i] == 0x7d) {
 440                                                 i++;
 441                                                 decoded[dec_index++] = data[i] ^ 0x20;
 442                                         } else {
 443                                                 decoded[dec_index++] = data[i];
 444                                         }
 445                                 }
 446
 447                                 // Fix alignment
 448                                 if(dec_index % 2 != 0)
 449                                         dec_index++;
 450
 451                                 #ifdef DEBUG
 452                                 printf("binary packet %d -> %d\n", data_length, dec_index);
 453                                 #endif
 454
 455                                 if(flash_populate(addr, decoded, dec_index) < 0) {
 456                                         reply = strdup("E00");
 457                                 } else {
 458                                         reply = strdup("OK");
 459                                 }
 460                         } else if(!strcmp(cmdName, "FlashDone")) {
 461                                 if(flash_go(sl) < 0) {
 462                                         reply = strdup("E00");
 463                                 } else {
 464                                         reply = strdup("OK");
 465                                 }
 466                         } else if(!strcmp(cmdName, "Kill")) {
 467                                 attached = 0;
 468
 469                                 reply = strdup("OK");
 470                         }
 471
 472                         if(reply == NULL)
 473                                 reply = strdup("");
 474
 475                         break;
 476                 }
 477
 478                 case 'c':
 479                         stlink_run(sl);
 480
 481                         while(1) {
 482                                 int status = gdb_check_for_interrupt(client);
 483                                 if(status < 0) {
 484                                         fprintf(stderr, "cannot check for int: %d\n", status);
 485                                         return 1;
 486                                 }
 487
 488                                 if(status == 1) {
 489                                         stlink_force_debug(sl);
 490                                         break;
 491                                 }
 492
 493                                 stlink_status(sl);
 494                                 if(sl->core_stat == STLINK_CORE_HALTED) {
 495                                         break;
 496                                 }
 497
 498                                 usleep(100000);
 499                         }
 500
 501                         reply = strdup("S05"); // TRAP
 502                         break;
 503
 504                 case 's':
 505                         stlink_step(sl);
 506
 507                         reply = strdup("S05"); // TRAP
 508                         break;
 509
 510                 case '?':
 511                         if(attached) {
 512                                 reply = strdup("S05"); // TRAP
 513                         } else {
 514                                 /* Stub shall reply OK if not attached. */
 515                                 reply = strdup("OK");
 516                         }
 517                         break;
 518
 519                 case 'g':
 520                         stlink_read_all_regs(sl);
 521
 522                         reply = calloc(8 * 16 + 1, 1);
 523                         for(int i = 0; i < 16; i++)
 524                                 sprintf(&reply[i * 8], "%08x", htonl(sl->reg.r[i]));
 525
 526                         break;
 527
 528                 case 'p': {
 529                         unsigned id = strtoul(&packet[1], NULL, 16), reg = 0xDEADDEAD;
 530
 531                         if(id < 16) {
 532                                 stlink_read_reg(sl, id);
 533                                 reg = htonl(sl->reg.r[id]);
 534                         } else if(id == 0x19) {
 535                                 stlink_read_reg(sl, 16);
 536                                 reg = htonl(sl->reg.xpsr);
 537                         } else {
 538                                 reply = strdup("E00");
 539                         }
 540
 541                         reply = calloc(8 + 1, 1);
 542                         sprintf(reply, "%08x", reg);
 543
 544                         break;
 545                 }
 546
 547                 case 'P': {
 548                         char* s_reg = &packet[1];
 549                         char* s_value = strstr(&packet[1], "=") + 1;
 550
 551                         unsigned reg   = strtoul(s_reg,   NULL, 16);
 552                         unsigned value = strtoul(s_value, NULL, 16);
 553
 554                         if(reg < 16) {
 555                                 stlink_write_reg(sl, ntohl(value), reg);
 556                         } else if(reg == 0x19) {
 557                                 stlink_write_reg(sl, ntohl(value), 16);
 558                         } else {
 559                                 reply = strdup("E00");
 560                         }
 561
 562                         if(!reply) {
 563                                 reply = strdup("OK");
 564                         }
 565
 566                         break;
 567                 }
 568
 569                 case 'G':
 570                         for(int i = 0; i < 16; i++) {
 571                                 char str[9] = {0};
 572                                 strncpy(str, &packet[1 + i * 8], 8);
 573                                 uint32_t reg = strtoul(str, NULL, 16);
 574                                 stlink_write_reg(sl, ntohl(reg), i);
 575                         }
 576
 577                         reply = strdup("OK");
 578                         break;
 579
 580                 case 'm': {
 581                         char* s_start = &packet[1];
 582                         char* s_count = strstr(&packet[1], ",") + 1;
 583
 584                         stm32_addr_t start = strtoul(s_start, NULL, 16);
 585                         unsigned     count = strtoul(s_count, NULL, 16);
 586
 587                         unsigned adj_start = start % 4;
 588
 589                         stlink_read_mem32(sl, start - adj_start, (count % 4 == 0) ?
 590                                                 count : count + 4 - (count % 4));
 591
 592                         reply = calloc(count * 2 + 1, 1);
 593                         for(int i = 0; i < count; i++) {
 594                                 reply[i * 2 + 0] = hex[sl->q_buf[i + adj_start] >> 4];
 595                                 reply[i * 2 + 1] = hex[sl->q_buf[i + adj_start] & 0xf];
 596                         }
 597
 598                         break;
 599                 }
 600
 601                 case 'M': {
 602                         char* s_start = &packet[1];
 603                         char* s_count = strstr(&packet[1], ",") + 1;
 604                         char* hexdata = strstr(packet, ":") + 1;
 605
 606                         stm32_addr_t start = strtoul(s_start, NULL, 16);
 607                         unsigned     count = strtoul(s_count, NULL, 16);
 608
 609                         for(int i = 0; i < count; i ++) {
 610                                 char hex[3] = { hexdata[i*2], hexdata[i*2+1], 0 };
 611                                 uint8_t byte = strtoul(hex, NULL, 16);
 612                                 sl->q_buf[i] = byte;
 613                         }
 614
 615                         if((count % 4) == 0 && (start % 4) == 0) {
 616                                 stlink_write_mem32(sl, start, count);
 617                         } else {
 618                                 stlink_write_mem8(sl, start, count);
 619                         }
 620
 621                         reply = strdup("OK");
 622
 623                         break;
 624                 }
 625
 626                 case 'Z': {
 627                         if(packet[1] == '1') {
 628                                 stm32_addr_t addr = strtoul(&packet[3], NULL, 16);
 629                                 if(update_code_breakpoint(sl, addr, 1) < 0) {
 630                                         reply = strdup("E00");
 631                                 } else {
 632                                         reply = strdup("OK");
 633                                 }
 634                         } else {
 635                                 reply = strdup("");
 636                         }
 637
 638                         break;
 639                 }
 640
 641                 case 'z': {
 642                         if(packet[1] == '1') {
 643                                 stm32_addr_t addr = strtoul(&packet[3], NULL, 16);
 644                                 update_code_breakpoint(sl, addr, 0);
 645
 646                                 reply = strdup("OK");
 647                         } else {
 648                                 reply = strdup("");
 649                         }
 650
 651                         break;
 652                 }
 653
 654                 case '!': {
 655                         /*
 656                          * Enter extended mode which allows restarting.
 657                          * We do support that always.
 658                          */
 659
 660                         reply = strdup("OK");
 661
 662                         break;
 663                 }
 664
 665                 case 'R': {
 666                         /* Reset the core. */
 667
 668                         stlink_reset(sl);
 669                         init_code_breakpoints(sl);
 670
 671                         attached = 1;
 672
 673                         reply = strdup("OK");
 674
 675                         break;
 676                 }
 677
 678                 default:
 679                         reply = strdup("");
 680                 }
 681
 682                 if(reply) {
 683                         #ifdef DEBUG
 684                         printf("send: %s\n", reply);
 685                         #endif
 686
 687                         int result = gdb_send_packet(client, reply);
 688                         if(result != 0) {
 689                                 fprintf(stderr, "cannot send: %d\n", result);
 690                                 return 1;
 691                         }
 692
 693                         free(reply);
 694                 }
 695
 696                 free(packet);
 697         }
 698
 699         return 0;
 700 }