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  *   Copyright (C) 2008 by Spencer Oliver                                  *
   6  *   spen@spen-soft.co.uk                                                  *
   7  *                                                                         *
   8  *   This program is free software; you can redistribute it and/or modify  *
   9  *   it under the terms of the GNU General Public License as published by  *
  10  *   the Free Software Foundation; either version 2 of the License, or     *
  11  *   (at your option) any later version.                                   *
  12  *                                                                         *
  13  *   This program is distributed in the hope that it will be useful,       *
  14  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  15  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  16  *   GNU General Public License for more details.                          *
  17  *                                                                         *
  18  *   You should have received a copy of the GNU General Public License     *
  19  *   along with this program; if not, write to the                         *
  20  *   Free Software Foundation, Inc.,                                       *
  21  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
  22  ***************************************************************************/
  23
  24 #ifdef HAVE_CONFIG_H
  25 #include "config.h"
  26 #endif
  27
  28 #include "replacements.h"
  29
  30 #include "jtag.h"
  31
  32 #include <usb.h>
  33 #include <string.h>
  34
  35 #include "log.h"
  36
  37 /* enable this to debug communication
  38  */
  39 #if 0
  40 #define _DEBUG_USB_COMMS_
  41 #endif
  42
  43 #ifdef _DEBUG_JTAG_IO_
  44 #define DEBUG_JTAG_IO(expr ...) LOG_DEBUG(expr)
  45 #else
  46 #define DEBUG_JTAG_IO(expr ...)
  47 #endif
  48
  49 #define VID 0x1366
  50 #define PID 0x0101
  51
  52 #define JLINK_WRITE_ENDPOINT    0x02
  53 #define JLINK_READ_ENDPOINT             0x81
  54
  55 #define JLINK_USB_TIMEOUT               1000
  56
  57 #define JLINK_IN_BUFFER_SIZE                    8192
  58 #define JLINK_OUT_BUFFER_SIZE                   8192
  59 #define JLINK_EMU_RESULT_BUFFER_SIZE    64
  60
  61 /* Global USB buffers */
  62 static u8 usb_in_buffer[JLINK_IN_BUFFER_SIZE];
  63 static u8 usb_out_buffer[JLINK_OUT_BUFFER_SIZE];
  64 static u8 usb_emu_result_buffer[JLINK_EMU_RESULT_BUFFER_SIZE];
  65
  66 /* Constants for JLink command */
  67 #define EMU_CMD_VERSION     0x01
  68 #define EMU_CMD_SET_SPEED   0x05
  69 #define EMU_CMD_GET_STATE   0x07
  70 #define EMU_CMD_HW_JTAG3    0xcf
  71 #define EMU_CMD_HW_RESET0   0xdc
  72 #define EMU_CMD_HW_RESET1   0xdd
  73 #define EMU_CMD_HW_TRST0    0xde
  74 #define EMU_CMD_HW_TRST1    0xdf
  75
  76 /* max speed 12MHz v5.0 jlink */
  77 #define JLINK_MAX_SPEED 12000
  78
  79 /* External interface functions */
  80 int jlink_execute_queue(void);
  81 int jlink_speed(int speed);
  82 int jlink_speed_div(int speed, int* khz);
  83 int jlink_khz(int khz, int *jtag_speed);
  84 int jlink_register_commands(struct command_context_s *cmd_ctx);
  85 int jlink_init(void);
  86 int jlink_quit(void);
  87
  88 /* CLI command handler functions */
  89 int jlink_handle_jlink_info_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
  90
  91 /* Queue command functions */
  92 void jlink_end_state(tap_state_t state);
  93 void jlink_state_move(void);
  94 void jlink_path_move(int num_states, tap_state_t *path);
  95 void jlink_runtest(int num_cycles);
  96 void jlink_scan(int ir_scan, enum scan_type type, u8 *buffer, int scan_size, scan_command_t *command);
  97 void jlink_reset(int trst, int srst);
  98 void jlink_simple_command(u8 command);
  99 int jlink_get_status(void);
 100
 101 /* J-Link tap buffer functions */
 102 void jlink_tap_init(void);
 103 int jlink_tap_execute(void);
 104 void jlink_tap_ensure_space(int scans, int bits);
 105 void jlink_tap_append_step(int tms, int tdi);
 106 void jlink_tap_append_scan(int length, u8 *buffer, scan_command_t *command);
 107
 108 /* Jlink lowlevel functions */
 109 typedef struct jlink_jtag
 110 {
 111         struct usb_dev_handle* usb_handle;
 112 } jlink_jtag_t;
 113
 114 jlink_jtag_t *jlink_usb_open(void);
 115 void jlink_usb_close(jlink_jtag_t *jlink_jtag);
 116 int jlink_usb_message(jlink_jtag_t *jlink_jtag, int out_length, int in_length);
 117 int jlink_usb_write(jlink_jtag_t *jlink_jtag, int out_length);
 118 int jlink_usb_read(jlink_jtag_t *jlink_jtag);
 119 int jlink_usb_read_emu_result(jlink_jtag_t *jlink_jtag);
 120
 121 /* helper functions */
 122 int jlink_get_version_info(void);
 123
 124 #ifdef _DEBUG_USB_COMMS_
 125 void jlink_debug_buffer(u8 *buffer, int length);
 126 #endif
 127
 128 jlink_jtag_t* jlink_jtag_handle;
 129
 130 /***************************************************************************/
 131 /* External interface implementation */
 132
 133 jtag_interface_t jlink_interface =
 134 {
 135         .name = "jlink",
 136         .execute_queue = jlink_execute_queue,
 137         .speed = jlink_speed,
 138         .speed_div = jlink_speed_div,
 139         .khz = jlink_khz,
 140         .register_commands = jlink_register_commands,
 141         .init = jlink_init,
 142         .quit = jlink_quit
 143 };
 144
 145 int jlink_execute_queue(void)
 146 {
 147         jtag_command_t *cmd = jtag_command_queue;
 148         int scan_size;
 149         enum scan_type type;
 150         u8 *buffer;
 151
 152         while (cmd != NULL)
 153         {
 154                 switch (cmd->type)
 155                 {
 156                         case JTAG_END_STATE:
 157                                 DEBUG_JTAG_IO("end_state: %i", cmd->cmd.end_state->end_state);
 158
 159                                 if (cmd->cmd.end_state->end_state != TAP_INVALID)
 160                                 {
 161                                         jlink_end_state(cmd->cmd.end_state->end_state);
 162                                 }
 163                                 break;
 164
 165                         case JTAG_RUNTEST:
 166                                 DEBUG_JTAG_IO( "runtest %i cycles, end in %i", cmd->cmd.runtest->num_cycles, \
 167                                         cmd->cmd.runtest->end_state);
 168
 169                                 if (cmd->cmd.runtest->end_state != TAP_INVALID)
 170                                 {
 171                                         jlink_end_state(cmd->cmd.runtest->end_state);
 172                                 }
 173                                 jlink_runtest(cmd->cmd.runtest->num_cycles);
 174                                 break;
 175
 176                         case JTAG_STATEMOVE:
 177                                 DEBUG_JTAG_IO("statemove end in %i", cmd->cmd.statemove->end_state);
 178
 179                                 if (cmd->cmd.statemove->end_state != TAP_INVALID)
 180                                 {
 181                                         jlink_end_state(cmd->cmd.statemove->end_state);
 182                                 }
 183                                 jlink_state_move();
 184                                 break;
 185
 186                         case JTAG_PATHMOVE:
 187                                 DEBUG_JTAG_IO("pathmove: %i states, end in %i", \
 188                                         cmd->cmd.pathmove->num_states, \
 189                                         cmd->cmd.pathmove->path[cmd->cmd.pathmove->num_states - 1]);
 190
 191                                 jlink_path_move(cmd->cmd.pathmove->num_states, cmd->cmd.pathmove->path);
 192                                 break;
 193
 194                         case JTAG_SCAN:
 195                                 DEBUG_JTAG_IO("scan end in %i", cmd->cmd.scan->end_state);
 196
 197                                 if (cmd->cmd.scan->end_state != TAP_INVALID)
 198                                 {
 199                                         jlink_end_state(cmd->cmd.scan->end_state);
 200                                 }
 201
 202                                 scan_size = jtag_build_buffer(cmd->cmd.scan, &buffer);
 203                                 DEBUG_JTAG_IO("scan input, length = %d", scan_size);
 204
 205 #ifdef _DEBUG_USB_COMMS_
 206                                 jlink_debug_buffer(buffer, (scan_size + 7) / 8);
 207 #endif
 208                                 type = jtag_scan_type(cmd->cmd.scan);
 209                                 jlink_scan(cmd->cmd.scan->ir_scan, type, buffer, scan_size, cmd->cmd.scan);
 210                                 break;
 211
 212                         case JTAG_RESET:
 213                                 DEBUG_JTAG_IO("reset trst: %i srst %i", cmd->cmd.reset->trst, cmd->cmd.reset->srst);
 214
 215                                 jlink_tap_execute();
 216
 217                                 if (cmd->cmd.reset->trst == 1)
 218                                 {
 219                                         tap_set_state(TAP_RESET);
 220                                 }
 221                                 jlink_reset(cmd->cmd.reset->trst, cmd->cmd.reset->srst);
 222                                 break;
 223
 224                         case JTAG_SLEEP:
 225                                 DEBUG_JTAG_IO("sleep %i", cmd->cmd.sleep->us);
 226                                 jlink_tap_execute();
 227                                 jtag_sleep(cmd->cmd.sleep->us);
 228                                 break;
 229
 230                         default:
 231                                 LOG_ERROR("BUG: unknown JTAG command type encountered");
 232                                 exit(-1);
 233                 }
 234                 cmd = cmd->next;
 235         }
 236
 237         return jlink_tap_execute();
 238 }
 239
 240 /* Sets speed in kHz. */
 241 int jlink_speed(int speed)
 242 {
 243         int result;
 244
 245         if (speed <= JLINK_MAX_SPEED)
 246         {
 247                 /* check for RTCK setting */
 248                 if (speed == 0)
 249                         speed = -1;
 250
 251                 usb_out_buffer[0] = EMU_CMD_SET_SPEED;
 252                 usb_out_buffer[1] = (speed >> 0) & 0xff;
 253                 usb_out_buffer[2] = (speed >> 8) & 0xff;
 254
 255                 result = jlink_usb_write(jlink_jtag_handle, 3);
 256
 257                 if (result == 3)
 258                 {
 259                         return ERROR_OK;
 260                 }
 261                 else
 262                 {
 263                         LOG_ERROR("J-Link setting speed failed (%d)", result);
 264                         return ERROR_JTAG_DEVICE_ERROR;
 265                 }
 266         }
 267         else
 268         {
 269                 LOG_INFO("Requested speed %dkHz exceeds maximum of %dkHz, ignored", speed, JLINK_MAX_SPEED);
 270         }
 271
 272         return ERROR_OK;
 273 }
 274
 275 int jlink_speed_div(int speed, int* khz)
 276 {
 277         *khz = speed;
 278
 279         return ERROR_OK;
 280 }
 281
 282 int jlink_khz(int khz, int *jtag_speed)
 283 {
 284         *jtag_speed = khz;
 285
 286         return ERROR_OK;
 287 }
 288
 289 int jlink_register_commands(struct command_context_s *cmd_ctx)
 290 {
 291         register_command(cmd_ctx, NULL, "jlink_info", jlink_handle_jlink_info_command, COMMAND_EXEC,
 292                 "query jlink info");
 293         return ERROR_OK;
 294 }
 295
 296 int jlink_init(void)
 297 {
 298         int check_cnt;
 299
 300         jlink_jtag_handle = jlink_usb_open();
 301
 302         if (jlink_jtag_handle == 0)
 303         {
 304                 LOG_ERROR("Cannot find jlink Interface! Please check connection and permissions.");
 305                 return ERROR_JTAG_INIT_FAILED;
 306         }
 307
 308         check_cnt = 0;
 309         while (check_cnt < 3)
 310         {
 311                 if (jlink_get_version_info() == ERROR_OK)
 312                 {
 313                         /* attempt to get status */
 314                         jlink_get_status();
 315                         break;
 316                 }
 317
 318                 check_cnt++;
 319         }
 320
 321         if (check_cnt == 3)
 322         {
 323                 LOG_INFO("J-Link initial read failed, don't worry");
 324         }
 325
 326         LOG_INFO("J-Link JTAG Interface ready");
 327
 328         jlink_reset(0, 0);
 329         jlink_tap_init();
 330
 331         return ERROR_OK;
 332 }
 333
 334 int jlink_quit(void)
 335 {
 336         jlink_usb_close(jlink_jtag_handle);
 337         return ERROR_OK;
 338 }
 339
 340 /***************************************************************************/
 341 /* Queue command implementations */
 342
 343 void jlink_end_state(tap_state_t state)
 344 {
 345         if (tap_is_state_stable(state))
 346         {
 347                 tap_set_end_state(state);
 348         }
 349         else
 350         {
 351                 LOG_ERROR("BUG: %i is not a valid end state", state);
 352                 exit(-1);
 353         }
 354 }
 355
 356 /* Goes to the end state. */
 357 void jlink_state_move(void)
 358 {
 359         int i;
 360         int tms = 0;
 361         u8 tms_scan = tap_get_tms_path(tap_get_state(), tap_get_end_state());
 362
 363         for (i = 0; i < 7; i++)
 364         {
 365                 tms = (tms_scan >> i) & 1;
 366                 jlink_tap_append_step(tms, 0);
 367         }
 368
 369         tap_set_state(tap_get_end_state());
 370 }
 371
 372 void jlink_path_move(int num_states, tap_state_t *path)
 373 {
 374         int i;
 375
 376         for (i = 0; i < num_states; i++)
 377         {
 378                 if (path[i] == tap_state_transition(tap_get_state(), false))
 379                 {
 380                         jlink_tap_append_step(0, 0);
 381                 }
 382                 else if (path[i] == tap_state_transition(tap_get_state(), true))
 383                 {
 384                         jlink_tap_append_step(1, 0);
 385                 }
 386                 else
 387                 {
 388                         LOG_ERROR("BUG: %s -> %s isn't a valid TAP transition", tap_state_name(tap_get_state()), tap_state_name(path[i]));
 389                         exit(-1);
 390                 }
 391
 392                 tap_set_state(path[i]);
 393         }
 394
 395         tap_set_end_state(tap_get_state());
 396 }
 397
 398 void jlink_runtest(int num_cycles)
 399 {
 400         int i;
 401
 402         tap_state_t saved_end_state = tap_get_end_state();
 403
 404         /* only do a state_move when we're not already in IDLE */
 405         if (tap_get_state() != TAP_IDLE)
 406         {
 407                 jlink_end_state(TAP_IDLE);
 408                 jlink_state_move();
 409         }
 410
 411         /* execute num_cycles */
 412         for (i = 0; i < num_cycles; i++)
 413         {
 414                 jlink_tap_append_step(0, 0);
 415         }
 416
 417         /* finish in end_state */
 418         jlink_end_state(saved_end_state);
 419         if (tap_get_state() != tap_get_end_state())
 420         {
 421                 jlink_state_move();
 422         }
 423 }
 424
 425 void jlink_scan(int ir_scan, enum scan_type type, u8 *buffer, int scan_size, scan_command_t *command)
 426 {
 427         tap_state_t saved_end_state;
 428
 429         jlink_tap_ensure_space(1, scan_size + 8);
 430
 431         saved_end_state = tap_get_end_state();
 432
 433         /* Move to appropriate scan state */
 434         jlink_end_state(ir_scan ? TAP_IRSHIFT : TAP_DRSHIFT);
 435
 436         jlink_state_move();
 437         jlink_end_state(saved_end_state);
 438
 439         /* Scan */
 440         jlink_tap_append_scan(scan_size, buffer, command);
 441
 442         /* We are in Exit1, go to Pause */
 443         jlink_tap_append_step(0, 0);
 444
 445         tap_set_state(ir_scan ? TAP_IRPAUSE : TAP_DRPAUSE);
 446
 447         if (tap_get_state() != tap_get_end_state())
 448         {
 449                 jlink_state_move();
 450         }
 451 }
 452
 453 void jlink_reset(int trst, int srst)
 454 {
 455         LOG_DEBUG("trst: %i, srst: %i", trst, srst);
 456
 457         /* Signals are active low */
 458         if (srst == 0)
 459         {
 460                 jlink_simple_command(EMU_CMD_HW_RESET1);
 461         }
 462         else if (srst == 1)
 463         {
 464                 jlink_simple_command(EMU_CMD_HW_RESET0);
 465         }
 466
 467         if (trst == 0)
 468         {
 469                 jlink_simple_command(EMU_CMD_HW_TRST1);
 470         }
 471         else if (trst == 1)
 472         {
 473                 jlink_simple_command(EMU_CMD_HW_TRST0);
 474         }
 475 }
 476
 477 void jlink_simple_command(u8 command)
 478 {
 479         int result;
 480
 481         DEBUG_JTAG_IO("0x%02x", command);
 482
 483         usb_out_buffer[0] = command;
 484         result = jlink_usb_write(jlink_jtag_handle, 1);
 485
 486         if (result != 1)
 487         {
 488                 LOG_ERROR("J-Link command 0x%02x failed (%d)", command, result);
 489         }
 490 }
 491
 492 int jlink_get_status(void)
 493 {
 494         int result;
 495
 496         jlink_simple_command(EMU_CMD_GET_STATE);
 497         result = jlink_usb_read(jlink_jtag_handle);
 498
 499         if (result == 8)
 500         {
 501                 int vref = usb_in_buffer[0] + (usb_in_buffer[1] << 8);
 502                 LOG_INFO("Vref = %d.%d TCK = %d TDI = %d TDO = %d TMS = %d SRST = %d TRST = %d\n", \
 503                         vref / 1000, vref % 1000, \
 504                         usb_in_buffer[2], usb_in_buffer[3], usb_in_buffer[4], \
 505                         usb_in_buffer[5], usb_in_buffer[6], usb_in_buffer[7]);
 506
 507                 if (vref < 1500)
 508                 {
 509                         LOG_ERROR("Vref too low. Check Target Power\n");
 510                 }
 511         }
 512         else
 513         {
 514                 LOG_ERROR("J-Link command EMU_CMD_GET_STATE failed (%d)\n", result);
 515         }
 516
 517         return ERROR_OK;
 518 }
 519
 520 int jlink_get_version_info(void)
 521 {
 522         int result;
 523         int len = 0;
 524
 525         /* query hardware version */
 526         jlink_simple_command(EMU_CMD_VERSION);
 527         result = jlink_usb_read(jlink_jtag_handle);
 528
 529         if (result == 2)
 530         {
 531                 len = buf_get_u32(usb_in_buffer, 0, 16);
 532                 result = jlink_usb_read(jlink_jtag_handle);
 533
 534                 if (result == len)
 535                 {
 536                         usb_in_buffer[result] = 0;
 537                         LOG_INFO((char *)usb_in_buffer);
 538                         return ERROR_OK;
 539                 }
 540         }
 541
 542         LOG_ERROR("J-Link command EMU_CMD_VERSION failed (%d)\n", result);
 543         return ERROR_JTAG_DEVICE_ERROR;
 544 }
 545
 546 int jlink_handle_jlink_info_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 547 {
 548         if (jlink_get_version_info() == ERROR_OK)
 549         {
 550                 /* attempt to get status */
 551                 jlink_get_status();
 552         }
 553
 554         return ERROR_OK;
 555 }
 556
 557 /***************************************************************************/
 558 /* J-Link tap functions */
 559
 560 /* 2048 is the max value we can use here */
 561 #define JLINK_TAP_BUFFER_SIZE 2048
 562
 563 static int tap_length;
 564 static u8 tms_buffer[JLINK_TAP_BUFFER_SIZE];
 565 static u8 tdi_buffer[JLINK_TAP_BUFFER_SIZE];
 566 static u8 tdo_buffer[JLINK_TAP_BUFFER_SIZE];
 567
 568 typedef struct
 569 {
 570         int first;      /* First bit position in tdo_buffer to read */
 571         int length; /* Number of bits to read */
 572         scan_command_t *command; /* Corresponding scan command */
 573         u8 *buffer;
 574 } pending_scan_result_t;
 575
 576 #define MAX_PENDING_SCAN_RESULTS 256
 577
 578 static int pending_scan_results_length;
 579 static pending_scan_result_t pending_scan_results_buffer[MAX_PENDING_SCAN_RESULTS];
 580
 581 static int last_tms;
 582
 583 void jlink_tap_init(void)
 584 {
 585         tap_length = 0;
 586         pending_scan_results_length = 0;
 587 }
 588
 589 void jlink_tap_ensure_space(int scans, int bits)
 590 {
 591         int available_scans = MAX_PENDING_SCAN_RESULTS - pending_scan_results_length;
 592         int available_bits = JLINK_TAP_BUFFER_SIZE * 8 - tap_length;
 593
 594         if (scans > available_scans || bits > available_bits)
 595         {
 596                 jlink_tap_execute();
 597         }
 598 }
 599
 600 void jlink_tap_append_step(int tms, int tdi)
 601 {
 602         last_tms = tms;
 603         int index = tap_length / 8;
 604
 605         if (index < JLINK_TAP_BUFFER_SIZE)
 606         {
 607                 int bit_index = tap_length % 8;
 608                 u8 bit = 1 << bit_index;
 609
 610                 if (tms)
 611                 {
 612                         tms_buffer[index] |= bit;
 613                 }
 614                 else
 615                 {
 616                         tms_buffer[index] &= ~bit;
 617                 }
 618
 619                 if (tdi)
 620                 {
 621                         tdi_buffer[index] |= bit;
 622                 }
 623                 else
 624                 {
 625                         tdi_buffer[index] &= ~bit;
 626                 }
 627
 628                 tap_length++;
 629         }
 630         else
 631         {
 632                 LOG_ERROR("jlink_tap_append_step, overflow");
 633         }
 634 }
 635
 636 void jlink_tap_append_scan(int length, u8 *buffer, scan_command_t *command)
 637 {
 638         pending_scan_result_t *pending_scan_result = &pending_scan_results_buffer[pending_scan_results_length];
 639         int i;
 640
 641         pending_scan_result->first = tap_length;
 642         pending_scan_result->length = length;
 643         pending_scan_result->command = command;
 644         pending_scan_result->buffer = buffer;
 645
 646         for (i = 0; i < length; i++)
 647         {
 648                 jlink_tap_append_step((i < length-1 ? 0 : 1), (buffer[i/8] >> (i%8)) & 1);
 649         }
 650         pending_scan_results_length++;
 651 }
 652
 653 /* Pad and send a tap sequence to the device, and receive the answer.
 654  * For the purpose of padding we assume that we are in idle or pause state. */
 655 int jlink_tap_execute(void)
 656 {
 657         int byte_length;
 658         int tms_offset;
 659         int tdi_offset;
 660         int i;
 661         int result;
 662
 663         if (tap_length > 0)
 664         {
 665                 /* Pad last byte so that tap_length is divisible by 8 */
 666                 while (tap_length % 8 != 0)
 667                 {
 668                         /* More of the last TMS value keeps us in the same state,
 669                          * analogous to free-running JTAG interfaces. */
 670                         jlink_tap_append_step(last_tms, 0);
 671                 }
 672
 673                 byte_length = tap_length / 8;
 674
 675                 usb_out_buffer[0] = EMU_CMD_HW_JTAG3;
 676                 usb_out_buffer[1] = 0;
 677                 usb_out_buffer[2] = (tap_length >> 0) & 0xff;
 678                 usb_out_buffer[3] = (tap_length >> 8) & 0xff;
 679
 680                 tms_offset = 4;
 681                 for (i = 0; i < byte_length; i++)
 682                 {
 683                         usb_out_buffer[tms_offset + i] = tms_buffer[i];
 684                 }
 685
 686                 tdi_offset = tms_offset + byte_length;
 687                 for (i = 0; i < byte_length; i++)
 688                 {
 689                         usb_out_buffer[tdi_offset + i] = tdi_buffer[i];
 690                 }
 691
 692                 result = jlink_usb_message(jlink_jtag_handle, 4 + 2 * byte_length, byte_length);
 693
 694                 if (result == byte_length)
 695                 {
 696                         for (i = 0; i < byte_length; i++)
 697                         {
 698                                 tdo_buffer[i] = usb_in_buffer[i];
 699                         }
 700
 701                         for (i = 0; i < pending_scan_results_length; i++)
 702                         {
 703                                 pending_scan_result_t *pending_scan_result = &pending_scan_results_buffer[i];
 704                                 u8 *buffer = pending_scan_result->buffer;
 705                                 int length = pending_scan_result->length;
 706                                 int first = pending_scan_result->first;
 707                                 scan_command_t *command = pending_scan_result->command;
 708
 709                                 /* Copy to buffer */
 710                                 buf_set_buf(tdo_buffer, first, buffer, 0, length);
 711
 712                                 DEBUG_JTAG_IO("pending scan result, length = %d", length);
 713
 714 #ifdef _DEBUG_USB_COMMS_
 715                                 jlink_debug_buffer(buffer, byte_length);
 716 #endif
 717
 718                                 if (jtag_read_buffer(buffer, command) != ERROR_OK)
 719                                 {
 720                                         jlink_tap_init();
 721                                         return ERROR_JTAG_QUEUE_FAILED;
 722                                 }
 723
 724                                 if (pending_scan_result->buffer != NULL)
 725                                 {
 726                                         free(pending_scan_result->buffer);
 727                                 }
 728                         }
 729                 }
 730                 else
 731                 {
 732                         LOG_ERROR("jlink_tap_execute, wrong result %d, expected %d", result, byte_length);
 733                         return ERROR_JTAG_QUEUE_FAILED;
 734                 }
 735
 736                 jlink_tap_init();
 737         }
 738
 739         return ERROR_OK;
 740 }
 741
 742 /*****************************************************************************/
 743 /* JLink USB low-level functions */
 744
 745 jlink_jtag_t* jlink_usb_open()
 746 {
 747         struct usb_bus *busses;
 748         struct usb_bus *bus;
 749         struct usb_device *dev;
 750
 751         jlink_jtag_t *result;
 752
 753         result = (jlink_jtag_t*) malloc(sizeof(jlink_jtag_t));
 754
 755         usb_init();
 756         usb_find_busses();
 757         usb_find_devices();
 758
 759         busses = usb_get_busses();
 760
 761         /* find jlink_jtag device in usb bus */
 762
 763         for (bus = busses; bus; bus = bus->next)
 764         {
 765                 for (dev = bus->devices; dev; dev = dev->next)
 766                 {
 767                         if ((dev->descriptor.idVendor == VID) && (dev->descriptor.idProduct == PID))
 768                         {
 769                                 result->usb_handle = usb_open(dev);
 770
 771                                 /* usb_set_configuration required under win32 */
 772                                 usb_set_configuration(result->usb_handle, dev->config[0].bConfigurationValue);
 773                                 usb_claim_interface(result->usb_handle, 0);
 774
 775 #if 0
 776                                 /*
 777                                  * This makes problems under Mac OS X. And is not needed
 778                                  * under Windows. Hopefully this will not break a linux build
 779                                  */
 780                                 usb_set_altinterface(result->usb_handle, 0);
 781 #endif
 782                                 return result;
 783                         }
 784                 }
 785         }
 786
 787         free(result);
 788         return NULL;
 789 }
 790
 791 void jlink_usb_close(jlink_jtag_t *jlink_jtag)
 792 {
 793         usb_close(jlink_jtag->usb_handle);
 794         free(jlink_jtag);
 795 }
 796
 797 /* Send a message and receive the reply. */
 798 int jlink_usb_message(jlink_jtag_t *jlink_jtag, int out_length, int in_length)
 799 {
 800         int result;
 801         int result2;
 802
 803         result = jlink_usb_write(jlink_jtag, out_length);
 804         if (result == out_length)
 805         {
 806                 result = jlink_usb_read(jlink_jtag);
 807                 if (result == in_length || result == in_length+1)
 808                 {
 809                         if (result == in_length)
 810                         {
 811                                 /* Must read the result from the EMU too */
 812                                 result2 = jlink_usb_read_emu_result(jlink_jtag);
 813                                 if (1 == result2)
 814                                 {
 815                                         /* Check the result itself */
 816                                         if (0 == usb_emu_result_buffer[0])
 817                                         {
 818                                                 return result;
 819                                         }
 820                                         else
 821                                         {
 822                                                 LOG_ERROR("jlink_usb_read_emu_result (requested=0, result=%d)", usb_emu_result_buffer[0]);
 823                                                 return -1;
 824                                         }
 825                                 }
 826                                 else
 827                                 {
 828                                         LOG_ERROR("jlink_usb_read_emu_result len (requested=1, result=%d)", result2);
 829                                         return -1;
 830                                 }
 831                         }
 832                         else
 833                         {
 834                                 /* Check the result itself */
 835                                 if (0 == usb_in_buffer[result-1])
 836                                 {
 837                                         return result-1;
 838                                 }
 839                                 else
 840                                 {
 841                                         LOG_ERROR("jlink_usb_read_emu_result (requested=0, result=%d)", usb_in_buffer[result]);
 842                                         return -1;
 843                                 }
 844                         }
 845                 }
 846                 else
 847                 {
 848                         LOG_ERROR("usb_bulk_read failed (requested=%d, result=%d)", in_length, result);
 849                         return -1;
 850                 }
 851         }
 852         else
 853         {
 854                 LOG_ERROR("usb_bulk_write failed (requested=%d, result=%d)", out_length, result);
 855                 return -1;
 856         }
 857 }
 858
 859 /* Write data from out_buffer to USB. */
 860 int jlink_usb_write(jlink_jtag_t *jlink_jtag, int out_length)
 861 {
 862         int result;
 863
 864         if (out_length > JLINK_OUT_BUFFER_SIZE)
 865         {
 866                 LOG_ERROR("jlink_jtag_write illegal out_length=%d (max=%d)", out_length, JLINK_OUT_BUFFER_SIZE);
 867                 return -1;
 868         }
 869
 870         result = usb_bulk_write(jlink_jtag->usb_handle, JLINK_WRITE_ENDPOINT,
 871                 (char *)usb_out_buffer, out_length, JLINK_USB_TIMEOUT);
 872
 873         DEBUG_JTAG_IO("jlink_usb_write, out_length = %d, result = %d", out_length, result);
 874
 875 #ifdef _DEBUG_USB_COMMS_
 876         jlink_debug_buffer(usb_out_buffer, out_length);
 877 #endif
 878         return result;
 879 }
 880
 881 /* Read data from USB into in_buffer. */
 882 int jlink_usb_read(jlink_jtag_t *jlink_jtag)
 883 {
 884         int result = usb_bulk_read(jlink_jtag->usb_handle, JLINK_READ_ENDPOINT,
 885                 (char *)usb_in_buffer, JLINK_IN_BUFFER_SIZE, JLINK_USB_TIMEOUT);
 886
 887         DEBUG_JTAG_IO("jlink_usb_read, result = %d", result);
 888
 889 #ifdef _DEBUG_USB_COMMS_
 890         jlink_debug_buffer(usb_in_buffer, result);
 891 #endif
 892         return result;
 893 }
 894
 895 /* Read the result from the previous EMU cmd into result_buffer. */
 896 int jlink_usb_read_emu_result(jlink_jtag_t *jlink_jtag)
 897 {
 898         int result = usb_bulk_read(jlink_jtag->usb_handle, JLINK_READ_ENDPOINT,
 899                 (char *)usb_emu_result_buffer, JLINK_EMU_RESULT_BUFFER_SIZE,
 900                 JLINK_USB_TIMEOUT);
 901
 902         DEBUG_JTAG_IO("jlink_usb_read_result, result = %d", result);
 903
 904 #ifdef _DEBUG_USB_COMMS_
 905         jlink_debug_buffer(usb_emu_result_buffer, result);
 906 #endif
 907         return result;
 908 }
 909
 910 #ifdef _DEBUG_USB_COMMS_
 911 #define BYTES_PER_LINE  16
 912
 913 void jlink_debug_buffer(u8 *buffer, int length)
 914 {
 915         char line[81];
 916         char s[4];
 917         int i;
 918         int j;
 919
 920         for (i = 0; i < length; i += BYTES_PER_LINE)
 921         {
 922                 snprintf(line, 5, "%04x", i);
 923                 for (j = i; j < i + BYTES_PER_LINE && j < length; j++)
 924                 {
 925                         snprintf(s, 4, " %02x", buffer[j]);
 926                         strcat(line, s);
 927                 }
 928                 LOG_DEBUG(line);
 929         }
 930 }
 931 #endif