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