git.sur5r.net Git - openocd/blob - src/jtag/jlink.c

   1 /***************************************************************************
   2  *   Copyright (C) 2007 by Juergen Stuber <juergen@jstuber.net>            *
   3  *   based on Dominic Rath's and Benedikt Sauter's usbprog.c               *
   4  *                                                                         *
   5  *   This program is free software; you can redistribute it and/or modify  *
   6  *   it under the terms of the GNU General Public License as published by  *
   7  *   the Free Software Foundation; either version 2 of the License, or     *
   8  *   (at your option) any later version.                                   *
   9  *                                                                         *
  10  *   This program is distributed in the hope that it will be useful,       *
  11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  13  *   GNU General Public License for more details.                          *
  14  *                                                                         *
  15  *   You should have received a copy of the GNU General Public License     *
  16  *   along with this program; if not, write to the                         *
  17  *   Free Software Foundation, Inc.,                                       *
  18  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
  19  ***************************************************************************/
  20
  21 #ifdef HAVE_CONFIG_H
  22 #include "config.h"
  23 #endif
  24
  25 #include "replacements.h"
  26
  27 #include "jtag.h"
  28
  29 #include <usb.h>
  30 #include <string.h>
  31
  32 #include "log.h"
  33
  34 /* enable this to debug communication
  35  */
  36 #if 0
  37 #define _DEBUG_USB_COMMS_
  38 #endif
  39
  40 #ifdef _DEBUG_JTAG_IO_
  41 #define DEBUG_JTAG_IO(expr ...) LOG_DEBUG(expr)
  42 #else
  43 #define DEBUG_JTAG_IO(expr ...)
  44 #endif
  45
  46 #define VID 0x1366
  47 #define PID 0x0101
  48
  49 #define JLINK_WRITE_ENDPOINT    0x02
  50 #define JLINK_READ_ENDPOINT             0x81
  51
  52 #define JLINK_USB_TIMEOUT               100
  53
  54 #define JLINK_IN_BUFFER_SIZE                    8192
  55 #define JLINK_OUT_BUFFER_SIZE                   8192
  56 #define JLINK_EMU_RESULT_BUFFER_SIZE    64
  57
  58 /* Global USB buffers */
  59 static u8 usb_in_buffer[JLINK_IN_BUFFER_SIZE];
  60 static u8 usb_out_buffer[JLINK_OUT_BUFFER_SIZE];
  61 static u8 usb_emu_result_buffer[JLINK_EMU_RESULT_BUFFER_SIZE];
  62
  63 /* Constants for JLink command */
  64 #define EMU_CMD_VERSION     0x01
  65 #define EMU_CMD_SET_SPEED   0x05
  66 #define EMU_CMD_GET_STATE   0x07
  67 #define EMU_CMD_HW_JTAG3    0xcf
  68 #define EMU_CMD_HW_RESET0   0xdc
  69 #define EMU_CMD_HW_RESET1   0xdd
  70 #define EMU_CMD_HW_TRST0    0xde
  71 #define EMU_CMD_HW_TRST1    0xdf
  72
  73 /* max speed 12MHz v5.0 jlink */
  74 #define JLINK_MAX_SPEED 12000
  75
  76 /* External interface functions */
  77 int jlink_execute_queue(void);
  78 int jlink_speed(int speed);
  79 int jlink_khz(int khz, int *jtag_speed);
  80 int jlink_register_commands(struct command_context_s *cmd_ctx);
  81 int jlink_init(void);
  82 int jlink_quit(void);
  83
  84 /* CLI command handler functions */
  85 int jlink_handle_jlink_info_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
  86
  87 /* Queue command functions */
  88 void jlink_end_state(enum tap_state state);
  89 void jlink_state_move(void);
  90 void jlink_path_move(int num_states, enum tap_state *path);
  91 void jlink_runtest(int num_cycles);
  92 void jlink_scan(int ir_scan, enum scan_type type, u8 *buffer, int scan_size, scan_command_t *command);
  93 void jlink_reset(int trst, int srst);
  94 void jlink_simple_command(u8 command);
  95 int jlink_get_status(void);
  96
  97 /* J-Link tap buffer functions */
  98 void jlink_tap_init();
  99 int jlink_tap_execute();
 100 void jlink_tap_ensure_space(int scans, int bits);
 101 void jlink_tap_append_step(int tms, int tdi);
 102 void jlink_tap_append_scan(int length, u8 *buffer, scan_command_t *command);
 103
 104 /* Jlink lowlevel functions */
 105 typedef struct jlink_jtag
 106 {
 107         struct usb_dev_handle* usb_handle;
 108 } jlink_jtag_t;
 109
 110 jlink_jtag_t *jlink_usb_open(void);
 111 void jlink_usb_close(jlink_jtag_t *jlink_jtag);
 112 int jlink_usb_message(jlink_jtag_t *jlink_jtag, int out_length, int in_length);
 113 int jlink_usb_write(jlink_jtag_t *jlink_jtag, int out_length);
 114 int jlink_usb_read(jlink_jtag_t *jlink_jtag);
 115 int jlink_usb_read_emu_result(jlink_jtag_t *jlink_jtag);
 116
 117 /* helper functions */
 118 int jlink_get_version_info(void);
 119
 120 #ifdef _DEBUG_USB_COMMS_
 121 void jlink_debug_buffer(u8 *buffer, int length);
 122 #endif
 123
 124 jlink_jtag_t* jlink_jtag_handle;
 125
 126 /***************************************************************************/
 127 /* External interface implementation */
 128
 129 jtag_interface_t jlink_interface =
 130 {
 131         .name = "jlink",
 132         .execute_queue = jlink_execute_queue,
 133         .speed = jlink_speed,
 134         .khz = jlink_khz,
 135         .register_commands = jlink_register_commands,
 136         .init = jlink_init,
 137         .quit = jlink_quit
 138 };
 139
 140 int jlink_execute_queue(void)
 141 {
 142         jtag_command_t *cmd = jtag_command_queue;
 143         int scan_size;
 144         enum scan_type type;
 145         u8 *buffer;
 146
 147         while (cmd != NULL)
 148         {
 149                 switch (cmd->type)
 150                 {
 151                         case JTAG_END_STATE:
 152                                 DEBUG_JTAG_IO("end_state: %i", cmd->cmd.end_state->end_state);
 153
 154                                 if (cmd->cmd.end_state->end_state != -1)
 155                                 {
 156                                         jlink_end_state(cmd->cmd.end_state->end_state);
 157                                 }
 158                                 break;
 159
 160                         case JTAG_RUNTEST:
 161                                 DEBUG_JTAG_IO( "runtest %i cycles, end in %i", cmd->cmd.runtest->num_cycles, \
 162                                         cmd->cmd.runtest->end_state);
 163
 164                                 if (cmd->cmd.runtest->end_state != -1)
 165                                 {
 166                                         jlink_end_state(cmd->cmd.runtest->end_state);
 167                                 }
 168                                 jlink_runtest(cmd->cmd.runtest->num_cycles);
 169                                 break;
 170
 171                         case JTAG_STATEMOVE:
 172                                 DEBUG_JTAG_IO("statemove end in %i", cmd->cmd.statemove->end_state);
 173
 174                                 if (cmd->cmd.statemove->end_state != -1)
 175                                 {
 176                                         jlink_end_state(cmd->cmd.statemove->end_state);
 177                                 }
 178                                 jlink_state_move();
 179                                 break;
 180
 181                         case JTAG_PATHMOVE:
 182                                 DEBUG_JTAG_IO("pathmove: %i states, end in %i", \
 183                                         cmd->cmd.pathmove->num_states, \
 184                                         cmd->cmd.pathmove->path[cmd->cmd.pathmove->num_states - 1]);
 185
 186                                 jlink_path_move(cmd->cmd.pathmove->num_states, cmd->cmd.pathmove->path);
 187                                 break;
 188
 189                         case JTAG_SCAN:
 190                                 DEBUG_JTAG_IO("scan end in %i", cmd->cmd.scan->end_state);
 191
 192                                 if (cmd->cmd.scan->end_state != -1)
 193                                 {
 194                                         jlink_end_state(cmd->cmd.scan->end_state);
 195                                 }
 196
 197                                 scan_size = jtag_build_buffer(cmd->cmd.scan, &buffer);
 198                                 DEBUG_JTAG_IO("scan input, length = %d", scan_size);
 199
 200 #ifdef _DEBUG_USB_COMMS_
 201                                 jlink_debug_buffer(buffer, (scan_size + 7) / 8);
 202 #endif
 203                                 type = jtag_scan_type(cmd->cmd.scan);
 204                                 jlink_scan(cmd->cmd.scan->ir_scan, type, buffer, scan_size, cmd->cmd.scan);
 205                                 break;
 206
 207                         case JTAG_RESET:
 208                                 DEBUG_JTAG_IO("reset trst: %i srst %i", cmd->cmd.reset->trst, cmd->cmd.reset->srst);
 209
 210                                 jlink_tap_execute();
 211
 212                                 if (cmd->cmd.reset->trst == 1)
 213                                 {
 214                                         cur_state = TAP_TLR;
 215                                 }
 216                                 jlink_reset(cmd->cmd.reset->trst, cmd->cmd.reset->srst);
 217                                 break;
 218
 219                         case JTAG_SLEEP:
 220                                 DEBUG_JTAG_IO("sleep %i", cmd->cmd.sleep->us);
 221                                 jlink_tap_execute();
 222                                 jtag_sleep(cmd->cmd.sleep->us);
 223                                 break;
 224
 225                         default:
 226                                 LOG_ERROR("BUG: unknown JTAG command type encountered");
 227                                 exit(-1);
 228                 }
 229                 cmd = cmd->next;
 230         }
 231
 232         return jlink_tap_execute();
 233 }
 234
 235 /* Sets speed in kHz. */
 236 int jlink_speed(int speed)
 237 {
 238         int result;
 239
 240         if (speed <= JLINK_MAX_SPEED)
 241         {
 242                 /* check for RTCK setting */
 243                 if (speed == 0)
 244                         speed = -1;
 245
 246                 usb_out_buffer[0] = EMU_CMD_SET_SPEED;
 247                 usb_out_buffer[1] = (speed >> 0) & 0xff;
 248                 usb_out_buffer[2] = (speed >> 8) & 0xff;
 249
 250                 result = jlink_usb_write(jlink_jtag_handle, 3);
 251
 252                 if (result == 3)
 253                 {
 254                         return ERROR_OK;
 255                 }
 256                 else
 257                 {
 258                         LOG_ERROR("J-Link setting speed failed (%d)", result);
 259                         return ERROR_JTAG_DEVICE_ERROR;
 260                 }
 261         }
 262         else
 263         {
 264                 LOG_INFO("Requested speed %dkHz exceeds maximum of %dkHz, ignored", speed, JLINK_MAX_SPEED);
 265         }
 266
 267         return ERROR_OK;
 268 }
 269
 270 int jlink_khz(int khz, int *jtag_speed)
 271 {
 272         *jtag_speed = khz;
 273
 274         return ERROR_OK;
 275 }
 276
 277 int jlink_register_commands(struct command_context_s *cmd_ctx)
 278 {
 279         register_command(cmd_ctx, NULL, "jlink_info", jlink_handle_jlink_info_command, COMMAND_EXEC,
 280                 "query jlink info");
 281         return ERROR_OK;
 282 }
 283
 284 int jlink_init(void)
 285 {
 286         int check_cnt;
 287
 288         jlink_jtag_handle = jlink_usb_open();
 289
 290         if (jlink_jtag_handle == 0)
 291         {
 292                 LOG_ERROR("Cannot find jlink Interface! Please check connection and permissions.");
 293                 return ERROR_JTAG_INIT_FAILED;
 294         }
 295
 296         check_cnt = 0;
 297         while (check_cnt < 3)
 298         {
 299                 if (jlink_get_version_info() == ERROR_OK)
 300                 {
 301                         /* attempt to get status */
 302                         jlink_get_status();
 303                         break;
 304                 }
 305
 306                 check_cnt++;
 307         }
 308
 309         if (check_cnt == 3)
 310         {
 311                 LOG_INFO("J-Link initial read failed, don't worry");
 312         }
 313
 314         LOG_INFO("J-Link JTAG Interface ready");
 315
 316         jlink_reset(0, 0);
 317         jlink_tap_init();
 318
 319         return ERROR_OK;
 320 }
 321
 322 int jlink_quit(void)
 323 {
 324         jlink_usb_close(jlink_jtag_handle);
 325         return ERROR_OK;
 326 }
 327
 328 /***************************************************************************/
 329 /* Queue command implementations */
 330
 331 void jlink_end_state(enum tap_state state)
 332 {
 333         if (tap_move_map[state] != -1)
 334         {
 335                 end_state = state;
 336         }
 337         else
 338         {
 339                 LOG_ERROR("BUG: %i is not a valid end state", state);
 340                 exit(-1);
 341         }
 342 }
 343
 344 /* Goes to the end state. */
 345 void jlink_state_move(void)
 346 {
 347         int i;
 348         int tms = 0;
 349         u8 tms_scan = TAP_MOVE(cur_state, end_state);
 350
 351         for (i = 0; i < 7; i++)
 352         {
 353                 tms = (tms_scan >> i) & 1;
 354                 jlink_tap_append_step(tms, 0);
 355         }
 356
 357         cur_state = end_state;
 358 }
 359
 360 void jlink_path_move(int num_states, enum tap_state *path)
 361 {
 362         int i;
 363
 364         for (i = 0; i < num_states; i++)
 365         {
 366                 if (path[i] == tap_transitions[cur_state].low)
 367                 {
 368                         jlink_tap_append_step(0, 0);
 369                 }
 370                 else if (path[i] == tap_transitions[cur_state].high)
 371                 {
 372                         jlink_tap_append_step(1, 0);
 373                 }
 374                 else
 375                 {
 376                         LOG_ERROR("BUG: %s -> %s isn't a valid TAP transition", tap_state_strings[cur_state], tap_state_strings[path[i]]);
 377                         exit(-1);
 378                 }
 379
 380                 cur_state = path[i];
 381         }
 382
 383         end_state = cur_state;
 384 }
 385
 386 void jlink_runtest(int num_cycles)
 387 {
 388         int i;
 389
 390         enum tap_state saved_end_state = end_state;
 391
 392         /* only do a state_move when we're not already in RTI */
 393         if (cur_state != TAP_RTI)
 394         {
 395                 jlink_end_state(TAP_RTI);
 396                 jlink_state_move();
 397         }
 398
 399         /* execute num_cycles */
 400         for (i = 0; i < num_cycles; i++)
 401         {
 402                 jlink_tap_append_step(0, 0);
 403         }
 404
 405         /* finish in end_state */
 406         jlink_end_state(saved_end_state);
 407         if (cur_state != end_state)
 408         {
 409                 jlink_state_move();
 410         }
 411 }
 412
 413 void jlink_scan(int ir_scan, enum scan_type type, u8 *buffer, int scan_size, scan_command_t *command)
 414 {
 415         enum tap_state saved_end_state;
 416
 417         jlink_tap_ensure_space(1, scan_size + 8);
 418
 419         saved_end_state = end_state;
 420
 421         /* Move to appropriate scan state */
 422         jlink_end_state(ir_scan ? TAP_SI : TAP_SD);
 423
 424         jlink_state_move();
 425         jlink_end_state(saved_end_state);
 426
 427         /* Scan */
 428         jlink_tap_append_scan(scan_size, buffer, command);
 429
 430         /* We are in Exit1, go to Pause */
 431         jlink_tap_append_step(0, 0);
 432
 433         cur_state = ir_scan ? TAP_PI : TAP_PD;
 434
 435         if (cur_state != end_state)
 436         {
 437                 jlink_state_move();
 438         }
 439 }
 440
 441 void jlink_reset(int trst, int srst)
 442 {
 443         LOG_DEBUG("trst: %i, srst: %i", trst, srst);
 444
 445         /* Signals are active low */
 446         if (srst == 0)
 447         {
 448                 jlink_simple_command(EMU_CMD_HW_RESET1);
 449         }
 450         else if (srst == 1)
 451         {
 452                 jlink_simple_command(EMU_CMD_HW_RESET0);
 453         }
 454
 455         if (trst == 0)
 456         {
 457                 jlink_simple_command(EMU_CMD_HW_TRST1);
 458         }
 459         else if (trst == 1)
 460         {
 461                 jlink_simple_command(EMU_CMD_HW_TRST0);
 462         }
 463 }
 464
 465 void jlink_simple_command(u8 command)
 466 {
 467         int result;
 468
 469         DEBUG_JTAG_IO("0x%02x", command);
 470
 471         usb_out_buffer[0] = command;
 472         result = jlink_usb_write(jlink_jtag_handle, 1);
 473
 474         if (result != 1)
 475         {
 476                 LOG_ERROR("J-Link command 0x%02x failed (%d)", command, result);
 477         }
 478 }
 479
 480 int jlink_get_status(void)
 481 {
 482         int result;
 483
 484         jlink_simple_command(EMU_CMD_GET_STATE);
 485         result = jlink_usb_read(jlink_jtag_handle);
 486
 487         if (result == 8)
 488         {
 489                 int vref = usb_in_buffer[0] + (usb_in_buffer[1] << 8);
 490                 LOG_INFO("Vref = %d.%d TCK = %d TDI = %d TDO = %d TMS = %d SRST = %d TRST = %d\n", \
 491                         vref / 1000, vref % 1000, \
 492                         usb_in_buffer[2], usb_in_buffer[3], usb_in_buffer[4], \
 493                         usb_in_buffer[5], usb_in_buffer[6], usb_in_buffer[7]);
 494
 495                 if (vref < 1500)
 496                 {
 497                         LOG_ERROR("Vref too low. Check Target Power\n");
 498                 }
 499         }
 500         else
 501         {
 502                 LOG_ERROR("J-Link command EMU_CMD_GET_STATE failed (%d)\n", result);
 503         }
 504
 505         return ERROR_OK;
 506 }
 507
 508 int jlink_get_version_info(void)
 509 {
 510         int result;
 511         int len = 0;
 512
 513         /* query hardware version */
 514         jlink_simple_command(EMU_CMD_VERSION);
 515         result = jlink_usb_read(jlink_jtag_handle);
 516
 517         if (result == 2)
 518         {
 519                 len = buf_get_u32(usb_in_buffer, 0, 16);
 520                 result = jlink_usb_read(jlink_jtag_handle);
 521
 522                 if (result == len)
 523                 {
 524                         usb_in_buffer[result] = 0;
 525                         LOG_INFO(usb_in_buffer);
 526                         return ERROR_OK;
 527                 }
 528         }
 529
 530         LOG_ERROR("J-Link command EMU_CMD_VERSION failed (%d)\n", result);
 531         return ERROR_JTAG_DEVICE_ERROR;
 532 }
 533
 534 int jlink_handle_jlink_info_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 535 {
 536         if (jlink_get_version_info() == ERROR_OK)
 537         {
 538                 /* attempt to get status */
 539                 jlink_get_status();
 540         }
 541
 542         return ERROR_OK;
 543 }
 544
 545 /***************************************************************************/
 546 /* J-Link tap functions */
 547
 548 /* 2048 is the max value we can use here */
 549 #define JLINK_TAP_BUFFER_SIZE 2048
 550
 551 static int tap_length;
 552 static u8 tms_buffer[JLINK_TAP_BUFFER_SIZE];
 553 static u8 tdi_buffer[JLINK_TAP_BUFFER_SIZE];
 554 static u8 tdo_buffer[JLINK_TAP_BUFFER_SIZE];
 555
 556 typedef struct
 557 {
 558         int first;      /* First bit position in tdo_buffer to read */
 559         int length; /* Number of bits to read */
 560         scan_command_t *command; /* Corresponding scan command */
 561         u8 *buffer;
 562 } pending_scan_result_t;
 563
 564 #define MAX_PENDING_SCAN_RESULTS 256
 565
 566 static int pending_scan_results_length;
 567 static pending_scan_result_t pending_scan_results_buffer[MAX_PENDING_SCAN_RESULTS];
 568
 569 static int last_tms;
 570
 571 void jlink_tap_init()
 572 {
 573         tap_length = 0;
 574         pending_scan_results_length = 0;
 575 }
 576
 577 void jlink_tap_ensure_space(int scans, int bits)
 578 {
 579         int available_scans = MAX_PENDING_SCAN_RESULTS - pending_scan_results_length;
 580         int available_bits = JLINK_TAP_BUFFER_SIZE * 8 - tap_length;
 581
 582         if (scans > available_scans || bits > available_bits)
 583         {
 584                 jlink_tap_execute();
 585         }
 586 }
 587
 588 void jlink_tap_append_step(int tms, int tdi)
 589 {
 590         last_tms = tms;
 591         int index = tap_length / 8;
 592
 593         if (index < JLINK_TAP_BUFFER_SIZE)
 594         {
 595                 int bit_index = tap_length % 8;
 596                 u8 bit = 1 << bit_index;
 597
 598                 if (tms)
 599                 {
 600                         tms_buffer[index] |= bit;
 601                 }
 602                 else
 603                 {
 604                         tms_buffer[index] &= ~bit;
 605                 }
 606
 607                 if (tdi)
 608                 {
 609                         tdi_buffer[index] |= bit;
 610                 }
 611                 else
 612                 {
 613                         tdi_buffer[index] &= ~bit;
 614                 }
 615
 616                 tap_length++;
 617         }
 618         else
 619         {
 620                 LOG_ERROR("jlink_tap_append_step, overflow");
 621         }
 622 }
 623
 624 void jlink_tap_append_scan(int length, u8 *buffer, scan_command_t *command)
 625 {
 626         pending_scan_result_t *pending_scan_result = &pending_scan_results_buffer[pending_scan_results_length];
 627         int i;
 628
 629         pending_scan_result->first = tap_length;
 630         pending_scan_result->length = length;
 631         pending_scan_result->command = command;
 632         pending_scan_result->buffer = buffer;
 633
 634         for (i = 0; i < length; i++)
 635         {
 636                 jlink_tap_append_step((i < length-1 ? 0 : 1), (buffer[i/8] >> (i%8)) & 1);
 637         }
 638         pending_scan_results_length++;
 639 }
 640
 641 /* Pad and send a tap sequence to the device, and receive the answer.
 642  * For the purpose of padding we assume that we are in idle or pause state. */
 643 int jlink_tap_execute()
 644 {
 645         int byte_length;
 646         int tms_offset;
 647         int tdi_offset;
 648         int i;
 649         int result;
 650
 651         if (tap_length > 0)
 652         {
 653                 /* Pad last byte so that tap_length is divisible by 8 */
 654                 while (tap_length % 8 != 0)
 655                 {
 656                         /* More of the last TMS value keeps us in the same state,
 657                          * analogous to free-running JTAG interfaces. */
 658                         jlink_tap_append_step(last_tms, 0);
 659                 }
 660
 661                 byte_length = tap_length / 8;
 662
 663                 usb_out_buffer[0] = EMU_CMD_HW_JTAG3;
 664                 usb_out_buffer[1] = 0;
 665                 usb_out_buffer[2] = (tap_length >> 0) & 0xff;
 666                 usb_out_buffer[3] = (tap_length >> 8) & 0xff;
 667
 668                 tms_offset = 4;
 669                 for (i = 0; i < byte_length; i++)
 670                 {
 671                         usb_out_buffer[tms_offset + i] = tms_buffer[i];
 672                 }
 673
 674                 tdi_offset = tms_offset + byte_length;
 675                 for (i = 0; i < byte_length; i++)
 676                 {
 677                         usb_out_buffer[tdi_offset + i] = tdi_buffer[i];
 678                 }
 679
 680                 result = jlink_usb_message(jlink_jtag_handle, 4 + 2 * byte_length, byte_length);
 681
 682                 if (result == byte_length)
 683                 {
 684                         for (i = 0; i < byte_length; i++)
 685                         {
 686                                 tdo_buffer[i] = usb_in_buffer[i];
 687                         }
 688
 689                         for (i = 0; i < pending_scan_results_length; i++)
 690                         {
 691                                 pending_scan_result_t *pending_scan_result = &pending_scan_results_buffer[i];
 692                                 u8 *buffer = pending_scan_result->buffer;
 693                                 int length = pending_scan_result->length;
 694                                 int first = pending_scan_result->first;
 695                                 scan_command_t *command = pending_scan_result->command;
 696
 697                                 /* Copy to buffer */
 698                                 buf_set_buf(tdo_buffer, first, buffer, 0, length);
 699
 700                                 DEBUG_JTAG_IO("pending scan result, length = %d", length);
 701
 702 #ifdef _DEBUG_USB_COMMS_
 703                                 jlink_debug_buffer(buffer, byte_length);
 704 #endif
 705
 706                                 if (jtag_read_buffer(buffer, command) != ERROR_OK)
 707                                 {
 708                                         jlink_tap_init();
 709                                         return ERROR_JTAG_QUEUE_FAILED;
 710                                 }
 711
 712                                 if (pending_scan_result->buffer != NULL)
 713                                 {
 714                                         free(pending_scan_result->buffer);
 715                                 }
 716                         }
 717                 }
 718                 else
 719                 {
 720                         LOG_ERROR("jlink_tap_execute, wrong result %d, expected %d", result, byte_length);
 721                         return ERROR_JTAG_QUEUE_FAILED;
 722                 }
 723
 724                 jlink_tap_init();
 725         }
 726
 727         return ERROR_OK;
 728 }
 729
 730 /*****************************************************************************/
 731 /* JLink USB low-level functions */
 732
 733 jlink_jtag_t* jlink_usb_open()
 734 {
 735         struct usb_bus *busses;
 736         struct usb_bus *bus;
 737         struct usb_device *dev;
 738
 739         jlink_jtag_t *result;
 740
 741         result = (jlink_jtag_t*) malloc(sizeof(jlink_jtag_t));
 742
 743         usb_init();
 744         usb_find_busses();
 745         usb_find_devices();
 746
 747         busses = usb_get_busses();
 748
 749         /* find jlink_jtag device in usb bus */
 750
 751         for (bus = busses; bus; bus = bus->next)
 752         {
 753                 for (dev = bus->devices; dev; dev = dev->next)
 754                 {
 755                         if ((dev->descriptor.idVendor == VID) && (dev->descriptor.idProduct == PID))
 756                         {
 757                                 result->usb_handle = usb_open(dev);
 758
 759                                 /* usb_set_configuration required under win32 */
 760                                 usb_set_configuration(result->usb_handle, dev->config[0].bConfigurationValue);
 761                                 usb_claim_interface(result->usb_handle, 0);
 762
 763 #if 0
 764                                 /*
 765                                  * This makes problems under Mac OS X. And is not needed
 766                                  * under Windows. Hopefully this will not break a linux build
 767                                  */
 768                                 usb_set_altinterface(result->usb_handle, 0);
 769 #endif
 770                                 return result;
 771                         }
 772                 }
 773         }
 774
 775         free(result);
 776         return NULL;
 777 }
 778
 779 void jlink_usb_close(jlink_jtag_t *jlink_jtag)
 780 {
 781         usb_close(jlink_jtag->usb_handle);
 782         free(jlink_jtag);
 783 }
 784
 785 /* Send a message and receive the reply. */
 786 int jlink_usb_message(jlink_jtag_t *jlink_jtag, int out_length, int in_length)
 787 {
 788         int result;
 789         int result2;
 790
 791         result = jlink_usb_write(jlink_jtag, out_length);
 792         if (result == out_length)
 793         {
 794                 result = jlink_usb_read(jlink_jtag);
 795                 if (result == in_length || result == in_length+1)
 796                 {
 797                         if (result == in_length)
 798                         {
 799                                 /* Must read the result from the EMU too */
 800                                 result2 = jlink_usb_read_emu_result(jlink_jtag);
 801                                 if (1 == result2)
 802                                 {
 803                                         /* Check the result itself */
 804                                         if (0 == usb_emu_result_buffer[0])
 805                                         {
 806                                                 return result;
 807                                         }
 808                                         else
 809                                         {
 810                                                 LOG_ERROR("jlink_usb_read_emu_result (requested=0, result=%d)", usb_emu_result_buffer[0]);
 811                                                 return -1;
 812                                         }
 813                                 }
 814                                 else
 815                                 {
 816                                         LOG_ERROR("jlink_usb_read_emu_result len (requested=1, result=%d)", result2);
 817                                         return -1;
 818                                 }
 819                         }
 820                         else
 821                         {
 822                                 /* Check the result itself */
 823                                 if (0 == usb_in_buffer[result-1])
 824                                 {
 825                                         return result-1;
 826                                 }
 827                                 else
 828                                 {
 829                                         LOG_ERROR("jlink_usb_read_emu_result (requested=0, result=%d)", usb_in_buffer[result]);
 830                                         return -1;
 831                                 }
 832                         }
 833                 }
 834                 else
 835                 {
 836                         LOG_ERROR("usb_bulk_read failed (requested=%d, result=%d)", in_length, result);
 837                         return -1;
 838                 }
 839         }
 840         else
 841         {
 842                 LOG_ERROR("usb_bulk_write failed (requested=%d, result=%d)", out_length, result);
 843                 return -1;
 844         }
 845 }
 846
 847 /* Write data from out_buffer to USB. */
 848 int jlink_usb_write(jlink_jtag_t *jlink_jtag, int out_length)
 849 {
 850         int result;
 851
 852         if (out_length > JLINK_OUT_BUFFER_SIZE)
 853         {
 854                 LOG_ERROR("jlink_jtag_write illegal out_length=%d (max=%d)", out_length, JLINK_OUT_BUFFER_SIZE);
 855                 return -1;
 856         }
 857
 858         result = usb_bulk_write(jlink_jtag->usb_handle, JLINK_WRITE_ENDPOINT, \
 859                 usb_out_buffer, out_length, JLINK_USB_TIMEOUT);
 860
 861         DEBUG_JTAG_IO("jlink_usb_write, out_length = %d, result = %d", out_length, result);
 862
 863 #ifdef _DEBUG_USB_COMMS_
 864         jlink_debug_buffer(usb_out_buffer, out_length);
 865 #endif
 866         return result;
 867 }
 868
 869 /* Read data from USB into in_buffer. */
 870 int jlink_usb_read(jlink_jtag_t *jlink_jtag)
 871 {
 872         int result = usb_bulk_read(jlink_jtag->usb_handle, JLINK_READ_ENDPOINT, \
 873                 usb_in_buffer, JLINK_IN_BUFFER_SIZE, JLINK_USB_TIMEOUT);
 874
 875         DEBUG_JTAG_IO("jlink_usb_read, result = %d", result);
 876
 877 #ifdef _DEBUG_USB_COMMS_
 878         jlink_debug_buffer(usb_in_buffer, result);
 879 #endif
 880         return result;
 881 }
 882
 883 /* Read the result from the previous EMU cmd into result_buffer. */
 884 int jlink_usb_read_emu_result(jlink_jtag_t *jlink_jtag)
 885 {
 886         int result = usb_bulk_read(jlink_jtag->usb_handle, JLINK_READ_ENDPOINT, \
 887                 usb_emu_result_buffer, JLINK_EMU_RESULT_BUFFER_SIZE, JLINK_USB_TIMEOUT);
 888
 889         DEBUG_JTAG_IO("jlink_usb_read_result, result = %d", result);
 890
 891 #ifdef _DEBUG_USB_COMMS_
 892         jlink_debug_buffer(usb_emu_result_buffer, result);
 893 #endif
 894         return result;
 895 }
 896
 897 #ifdef _DEBUG_USB_COMMS_
 898 #define BYTES_PER_LINE  16
 899
 900 void jlink_debug_buffer(u8 *buffer, int length)
 901 {
 902         char line[81];
 903         char s[4];
 904         int i;
 905         int j;
 906
 907         for (i = 0; i < length; i += BYTES_PER_LINE)
 908         {
 909                 snprintf(line, 5, "%04x", i);
 910                 for (j = i; j < i + BYTES_PER_LINE && j < length; j++)
 911                 {
 912                         snprintf(s, 4, " %02x", buffer[j]);
 913                         strcat(line, s);
 914                 }
 915                 LOG_DEBUG(line);
 916         }
 917 }
 918 #endif