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   1 // vim:ts=4 sw=4:
   2
   3 /***************************************************************************
   4  *   Copyright (C) 2009 by Dimitar Dimitrov <dinuxbg@gmail.com>            *
   5  *   based on Dominic Rath's and Benedikt Sauter's usbprog.c               *
   6  *                                                                         *
   7  *   This program is free software; you can redistribute it and/or modify  *
   8  *   it under the terms of the GNU General Public License as published by  *
   9  *   the Free Software Foundation; either version 2 of the License, or     *
  10  *   (at your option) any later version.                                   *
  11  *                                                                         *
  12  *   This program is distributed in the hope that it will be useful,       *
  13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  15  *   GNU General Public License for more details.                          *
  16  *                                                                         *
  17  *   You should have received a copy of the GNU General Public License     *
  18  *   along with this program; if not, write to the                         *
  19  *   Free Software Foundation, Inc.,                                       *
  20  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
  21  ***************************************************************************/
  22
  23 #ifdef HAVE_CONFIG_H
  24 #include "config.h"
  25 #endif
  26
  27 #include "jtag.h"
  28 #include <usb.h>
  29
  30
  31 #define USB_VID                                         0x15ba
  32 #define USB_PID                                         0x001e
  33
  34 #define ARMJTAGEW_EPT_BULK_OUT          0x01u
  35 #define ARMJTAGEW_EPT_BULK_IN           0x82u
  36
  37 #define ARMJTAGEW_USB_TIMEOUT           2000
  38
  39 #define ARMJTAGEW_IN_BUFFER_SIZE        (4*1024)
  40 #define ARMJTAGEW_OUT_BUFFER_SIZE       (4*1024)
  41
  42
  43 /* USB command request codes. */
  44 #define CMD_GET_VERSION                         0x00
  45 #define CMD_SELECT_DPIMPL                       0x10
  46 #define CMD_SET_TCK_FREQUENCY           0x11
  47 #define CMD_GET_TCK_FREQUENCY           0x12
  48 #define CMD_MEASURE_MAX_TCK_FREQ        0x15
  49 #define CMD_MEASURE_RTCK_RESPONSE       0x16
  50 #define CMD_TAP_SHIFT                           0x17
  51 #define CMD_SET_TAPHW_STATE                     0x20
  52 #define CMD_GET_TAPHW_STATE                     0x21
  53 #define CMD_TGPWR_SETUP                         0x22
  54
  55 /* Global USB buffers */
  56 static u8 usb_in_buffer[ARMJTAGEW_IN_BUFFER_SIZE];
  57 static u8 usb_out_buffer[ARMJTAGEW_OUT_BUFFER_SIZE];
  58
  59 /* External interface functions */
  60 static int armjtagew_execute_queue(void);
  61 static int armjtagew_speed(int speed);
  62 static int armjtagew_khz(int khz, int *jtag_speed);
  63 static int armjtagew_register_commands(struct command_context_s *cmd_ctx);
  64 static int armjtagew_init(void);
  65 static int armjtagew_quit(void);
  66
  67 /* CLI command handler functions */
  68 static int armjtagew_handle_armjtagew_info_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
  69
  70 /* Queue command functions */
  71 static void armjtagew_end_state(tap_state_t state);
  72 static void armjtagew_state_move(void);
  73 static void armjtagew_path_move(int num_states, tap_state_t *path);
  74 static void armjtagew_runtest(int num_cycles);
  75 static void armjtagew_scan(bool ir_scan, enum scan_type type, u8 *buffer, int scan_size, scan_command_t *command);
  76 static void armjtagew_reset(int trst, int srst);
  77 //static void armjtagew_simple_command(u8 command);
  78 static int armjtagew_get_status(void);
  79
  80 /* tap buffer functions */
  81 static void armjtagew_tap_init(void);
  82 static int armjtagew_tap_execute(void);
  83 static void armjtagew_tap_ensure_space(int scans, int bits);
  84 static void armjtagew_tap_append_step(int tms, int tdi);
  85 static void armjtagew_tap_append_scan(int length, u8 *buffer, scan_command_t *command);
  86
  87 /* ARM-JTAG-EW lowlevel functions */
  88 typedef struct armjtagew_jtag
  89 {
  90         struct usb_dev_handle* usb_handle;
  91 } armjtagew_jtag_t;
  92
  93 static armjtagew_jtag_t *armjtagew_usb_open(void);
  94 static void armjtagew_usb_close(armjtagew_jtag_t *armjtagew_jtag);
  95 static int armjtagew_usb_message(armjtagew_jtag_t *armjtagew_jtag, int out_length, int in_length);
  96 static int armjtagew_usb_write(armjtagew_jtag_t *armjtagew_jtag, int out_length);
  97 static int armjtagew_usb_read(armjtagew_jtag_t *armjtagew_jtag, int exp_in_length);
  98
  99 /* helper functions */
 100 static int armjtagew_get_version_info(void);
 101
 102 #ifdef _DEBUG_USB_COMMS_
 103 static void armjtagew_debug_buffer(u8 *buffer, int length);
 104 #endif
 105
 106 static armjtagew_jtag_t* armjtagew_jtag_handle;
 107
 108
 109
 110 /***************************************************************************/
 111 /* External interface implementation */
 112
 113 jtag_interface_t armjtagew_interface =
 114 {
 115         .name = "arm-jtag-ew",
 116         .execute_queue = armjtagew_execute_queue,
 117         .speed = armjtagew_speed,
 118         .khz = armjtagew_khz,
 119         .register_commands = armjtagew_register_commands,
 120         .init = armjtagew_init,
 121         .quit = armjtagew_quit
 122 };
 123
 124
 125 static int armjtagew_execute_queue(void)
 126 {
 127         jtag_command_t *cmd = jtag_command_queue;
 128         int scan_size;
 129         enum scan_type type;
 130         u8 *buffer;
 131
 132         while (cmd != NULL)
 133         {
 134                 switch (cmd->type)
 135                 {
 136                         case JTAG_END_STATE:
 137                                 DEBUG_JTAG_IO("end_state: %i", cmd->cmd.end_state->end_state);
 138
 139                                 if (cmd->cmd.end_state->end_state != TAP_INVALID)
 140                                 {
 141                                         armjtagew_end_state(cmd->cmd.end_state->end_state);
 142                                 }
 143                                 break;
 144
 145                         case JTAG_RUNTEST:
 146                                 DEBUG_JTAG_IO( "runtest %i cycles, end in %i", cmd->cmd.runtest->num_cycles, \
 147                                         cmd->cmd.runtest->end_state);
 148
 149                                 if (cmd->cmd.runtest->end_state != TAP_INVALID)
 150                                 {
 151                                         armjtagew_end_state(cmd->cmd.runtest->end_state);
 152                                 }
 153                                 armjtagew_runtest(cmd->cmd.runtest->num_cycles);
 154                                 break;
 155
 156                         case JTAG_STATEMOVE:
 157                                 DEBUG_JTAG_IO("statemove end in %i", cmd->cmd.statemove->end_state);
 158
 159                                 if (cmd->cmd.statemove->end_state != TAP_INVALID)
 160                                 {
 161                                         armjtagew_end_state(cmd->cmd.statemove->end_state);
 162                                 }
 163                                 armjtagew_state_move();
 164                                 break;
 165
 166                         case JTAG_PATHMOVE:
 167                                 DEBUG_JTAG_IO("pathmove: %i states, end in %i", \
 168                                         cmd->cmd.pathmove->num_states, \
 169                                         cmd->cmd.pathmove->path[cmd->cmd.pathmove->num_states - 1]);
 170
 171                                 armjtagew_path_move(cmd->cmd.pathmove->num_states, cmd->cmd.pathmove->path);
 172                                 break;
 173
 174                         case JTAG_SCAN:
 175                                 DEBUG_JTAG_IO("scan end in %i", cmd->cmd.scan->end_state);
 176
 177                                 if (cmd->cmd.scan->end_state != TAP_INVALID)
 178                                 {
 179                                         armjtagew_end_state(cmd->cmd.scan->end_state);
 180                                 }
 181
 182                                 scan_size = jtag_build_buffer(cmd->cmd.scan, &buffer);
 183                                 DEBUG_JTAG_IO("scan input, length = %d", scan_size);
 184
 185 #ifdef _DEBUG_USB_COMMS_
 186                                 armjtagew_debug_buffer(buffer, (scan_size + 7) / 8);
 187 #endif
 188                                 type = jtag_scan_type(cmd->cmd.scan);
 189                                 armjtagew_scan(cmd->cmd.scan->ir_scan, type, buffer, scan_size, cmd->cmd.scan);
 190                                 break;
 191
 192                         case JTAG_RESET:
 193                                 DEBUG_JTAG_IO("reset trst: %i srst %i", cmd->cmd.reset->trst, cmd->cmd.reset->srst);
 194
 195                                 armjtagew_tap_execute();
 196
 197                                 if (cmd->cmd.reset->trst == 1)
 198                                 {
 199                                         tap_set_state(TAP_RESET);
 200                                 }
 201                                 armjtagew_reset(cmd->cmd.reset->trst, cmd->cmd.reset->srst);
 202                                 break;
 203
 204                         case JTAG_SLEEP:
 205                                 DEBUG_JTAG_IO("sleep %i", cmd->cmd.sleep->us);
 206                                 armjtagew_tap_execute();
 207                                 jtag_sleep(cmd->cmd.sleep->us);
 208                                 break;
 209
 210                         default:
 211                                 LOG_ERROR("BUG: unknown JTAG command type encountered");
 212                                 exit(-1);
 213                 }
 214                 cmd = cmd->next;
 215         }
 216
 217         return armjtagew_tap_execute();
 218 }
 219
 220
 221 /* Sets speed in kHz. */
 222 static int armjtagew_speed(int speed)
 223 {
 224     int result;
 225     int speed_real;
 226
 227
 228     usb_out_buffer[0] = CMD_SET_TCK_FREQUENCY;
 229         buf_set_u32(usb_out_buffer+1, 0, 32, speed);
 230
 231     result = armjtagew_usb_message(armjtagew_jtag_handle, 4, 4);
 232
 233     if (result < 0)
 234     {
 235         LOG_ERROR("ARM-JTAG-EW setting speed failed (%d)", result);
 236         return ERROR_JTAG_DEVICE_ERROR;
 237     }
 238
 239         usb_out_buffer[0] = CMD_GET_TCK_FREQUENCY;
 240     result = armjtagew_usb_message(armjtagew_jtag_handle, 1, 4);
 241         speed_real = (int)buf_get_u32(usb_in_buffer,0,32);
 242         if(result < 0)
 243         {
 244         LOG_ERROR("ARM-JTAG-EW getting speed failed (%d)", result);
 245         return ERROR_JTAG_DEVICE_ERROR;
 246         }
 247         else
 248         {
 249         LOG_INFO("Requested speed %dkHz, emulator reported %dkHz.", speed, speed_real);
 250         }
 251
 252     return ERROR_OK;
 253 }
 254
 255
 256 static int armjtagew_khz(int khz, int *jtag_speed)
 257 {
 258         *jtag_speed = khz;
 259
 260         return ERROR_OK;
 261 }
 262
 263 static int armjtagew_register_commands(struct command_context_s *cmd_ctx)
 264 {
 265         register_command(cmd_ctx, NULL, "armjtagew_info", armjtagew_handle_armjtagew_info_command, COMMAND_EXEC,
 266                 "query armjtagew info");
 267         return ERROR_OK;
 268 }
 269
 270 static int armjtagew_init(void)
 271 {
 272         int check_cnt;
 273
 274         armjtagew_jtag_handle = armjtagew_usb_open();
 275
 276         if (armjtagew_jtag_handle == 0)
 277         {
 278                 LOG_ERROR("Cannot find ARM-JTAG-EW Interface! Please check connection and permissions.");
 279                 return ERROR_JTAG_INIT_FAILED;
 280         }
 281
 282         check_cnt = 0;
 283         while (check_cnt < 3)
 284         {
 285                 if (armjtagew_get_version_info() == ERROR_OK)
 286                 {
 287                         /* attempt to get status */
 288                         armjtagew_get_status();
 289                         break;
 290                 }
 291
 292                 check_cnt++;
 293         }
 294
 295         if (check_cnt == 3)
 296         {
 297                 LOG_INFO("ARM-JTAG-EW initial read failed, don't worry");
 298         }
 299
 300         LOG_INFO("ARM-JTAG-EW JTAG Interface ready");
 301
 302         armjtagew_reset(0, 0);
 303         armjtagew_tap_init();
 304
 305         return ERROR_OK;
 306 }
 307
 308 static int armjtagew_quit(void)
 309 {
 310         armjtagew_usb_close(armjtagew_jtag_handle);
 311         return ERROR_OK;
 312 }
 313
 314 /***************************************************************************/
 315 /* Queue command implementations */
 316
 317 static void armjtagew_end_state(tap_state_t state)
 318 {
 319         if (tap_is_state_stable(state))
 320         {
 321                 tap_set_end_state(state);
 322         }
 323         else
 324         {
 325                 LOG_ERROR("BUG: %i is not a valid end state", state);
 326                 exit(-1);
 327         }
 328 }
 329
 330 /* Goes to the end state. */
 331 static void armjtagew_state_move(void)
 332 {
 333         int i;
 334         int tms = 0;
 335         u8 tms_scan = tap_get_tms_path(tap_get_state(), tap_get_end_state());
 336
 337         for (i = 0; i < 7; i++)
 338         {
 339                 tms = (tms_scan >> i) & 1;
 340                 armjtagew_tap_append_step(tms, 0);
 341         }
 342
 343         tap_set_state(tap_get_end_state());
 344 }
 345
 346 static void armjtagew_path_move(int num_states, tap_state_t *path)
 347 {
 348         int i;
 349
 350         for (i = 0; i < num_states; i++)
 351         {
 352                 /*
 353                  * TODO: The ARM-JTAG-EW hardware delays TDI with 3 TCK cycles when in RTCK mode.
 354                  * Either handle that here, or update the documentation with examples
 355                  * how to fix that in the configuration files.
 356                  */
 357                 if (path[i] == tap_state_transition(tap_get_state(), false))
 358                 {
 359                         armjtagew_tap_append_step(0, 0);
 360                 }
 361                 else if (path[i] == tap_state_transition(tap_get_state(), true))
 362                 {
 363                         armjtagew_tap_append_step(1, 0);
 364                 }
 365                 else
 366                 {
 367                         LOG_ERROR("BUG: %s -> %s isn't a valid TAP transition", tap_state_name(tap_get_state()), tap_state_name(path[i]));
 368                         exit(-1);
 369                 }
 370
 371                 tap_set_state(path[i]);
 372         }
 373
 374         tap_set_end_state(tap_get_state());
 375 }
 376
 377 static void armjtagew_runtest(int num_cycles)
 378 {
 379         int i;
 380
 381         tap_state_t saved_end_state = tap_get_end_state();
 382
 383         /* only do a state_move when we're not already in IDLE */
 384         if (tap_get_state() != TAP_IDLE)
 385         {
 386                 armjtagew_end_state(TAP_IDLE);
 387                 armjtagew_state_move();
 388         }
 389
 390         /* execute num_cycles */
 391         for (i = 0; i < num_cycles; i++)
 392         {
 393                 armjtagew_tap_append_step(0, 0);
 394         }
 395
 396         /* finish in end_state */
 397         armjtagew_end_state(saved_end_state);
 398         if (tap_get_state() != tap_get_end_state())
 399         {
 400                 armjtagew_state_move();
 401         }
 402 }
 403
 404 static void armjtagew_scan(bool ir_scan, enum scan_type type, u8 *buffer, int scan_size, scan_command_t *command)
 405 {
 406         tap_state_t saved_end_state;
 407
 408         armjtagew_tap_ensure_space(1, scan_size + 8);
 409
 410         saved_end_state = tap_get_end_state();
 411
 412         /* Move to appropriate scan state */
 413         armjtagew_end_state(ir_scan ? TAP_IRSHIFT : TAP_DRSHIFT);
 414
 415         armjtagew_state_move();
 416         armjtagew_end_state(saved_end_state);
 417
 418         /* Scan */
 419         armjtagew_tap_append_scan(scan_size, buffer, command);
 420
 421         /* We are in Exit1, go to Pause */
 422         armjtagew_tap_append_step(0, 0);
 423
 424         tap_set_state(ir_scan ? TAP_IRPAUSE : TAP_DRPAUSE);
 425
 426         if (tap_get_state() != tap_get_end_state())
 427         {
 428                 armjtagew_state_move();
 429         }
 430 }
 431
 432 static void armjtagew_reset(int trst, int srst)
 433 {
 434         const u8 trst_mask = (1u<<5);
 435         const u8 srst_mask = (1u<<6);
 436         u8 val = 0;
 437         u8 outp_en = 0;
 438         u8 change_mask = 0;
 439         int result;
 440
 441         LOG_DEBUG("trst: %i, srst: %i", trst, srst);
 442
 443         if (srst == 0)
 444         {
 445                 val |= srst_mask;
 446                 outp_en &= ~srst_mask;          /* tristate */
 447                 change_mask |= srst_mask;
 448         }
 449         else if (srst == 1)
 450         {
 451                 val &= ~srst_mask;
 452                 outp_en |= srst_mask;
 453                 change_mask |= srst_mask;
 454         }
 455
 456         if (trst == 0)
 457         {
 458                 val |= trst_mask;
 459                 outp_en &= ~trst_mask;          /* tristate */
 460                 change_mask |= trst_mask;
 461         }
 462         else if (trst == 1)
 463         {
 464                 val &= ~trst_mask;
 465                 outp_en |= trst_mask;
 466                 change_mask |= trst_mask;
 467         }
 468
 469         usb_out_buffer[0] = CMD_SET_TAPHW_STATE;
 470         usb_out_buffer[1] = val;
 471         usb_out_buffer[2] = outp_en;
 472         usb_out_buffer[3] = change_mask;
 473         result = armjtagew_usb_write(armjtagew_jtag_handle, 4);
 474         if (result != 4)
 475         {
 476                 LOG_ERROR("ARM-JTAG-EW TRST/SRST pin set failed failed (%d)", result);
 477         }
 478 }
 479
 480
 481 static int armjtagew_get_status(void)
 482 {
 483         int result;
 484
 485         usb_out_buffer[0] = CMD_GET_TAPHW_STATE;
 486         result = armjtagew_usb_message(armjtagew_jtag_handle, 1, 12);
 487
 488         if (result == 0)
 489         {
 490                 unsigned int u_tg = buf_get_u32(usb_in_buffer, 0, 16);
 491                 LOG_INFO("U_tg = %d mV, U_aux = %d mV, U_tgpwr = %d mV, I_tgpwr = %d mA, D1 = %d, Target power %s %s\n", \
 492                         buf_get_u32(usb_in_buffer + 0, 0, 16), \
 493                         buf_get_u32(usb_in_buffer + 2, 0, 16), \
 494                         buf_get_u32(usb_in_buffer + 4, 0, 16), \
 495                         buf_get_u32(usb_in_buffer + 6, 0, 16), \
 496                         usb_in_buffer[9], \
 497                         usb_in_buffer[11] ? "OVERCURRENT" : "OK", \
 498                         usb_in_buffer[10] ? "enabled" : "disabled");
 499
 500                 if (u_tg < 1500)
 501                 {
 502                         LOG_ERROR("Vref too low. Check Target Power\n");
 503                 }
 504         }
 505         else
 506         {
 507                 LOG_ERROR("ARM-JTAG-EW command CMD_GET_TAPHW_STATE failed (%d)\n", result);
 508         }
 509
 510         return ERROR_OK;
 511 }
 512
 513 static int armjtagew_get_version_info(void)
 514 {
 515         int result;
 516         char sn[16];
 517         char auxinfo[257];
 518
 519         /* query hardware version */
 520         usb_out_buffer[0] = CMD_GET_VERSION;
 521         result = armjtagew_usb_message(armjtagew_jtag_handle, 1, 4+15+256);
 522
 523         if (result != 0)
 524         {
 525                 LOG_ERROR("ARM-JTAG-EW command CMD_GET_VERSION failed (%d)\n", result);
 526                 return ERROR_JTAG_DEVICE_ERROR;
 527         }
 528
 529
 530         memcpy(sn, usb_in_buffer+4, 15);
 531         sn[15] = '\0';
 532         memcpy(auxinfo, usb_in_buffer+4+15, 256);
 533         auxinfo[256] = '\0';
 534
 535         LOG_INFO("ARM-JTAG-EW firmware version %d.%d, hardware revision %c, SN=%s, Additional info: %s", \
 536                         usb_in_buffer[1], usb_in_buffer[0], \
 537                         isgraph(usb_in_buffer[2]) ? usb_in_buffer[2] : 'X', \
 538                         sn, auxinfo);
 539         return ERROR_OK;
 540 }
 541
 542 static int armjtagew_handle_armjtagew_info_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 543 {
 544         if (armjtagew_get_version_info() == ERROR_OK)
 545         {
 546                 /* attempt to get status */
 547                 armjtagew_get_status();
 548         }
 549
 550         return ERROR_OK;
 551 }
 552
 553 /***************************************************************************/
 554 /* ARM-JTAG-EW tap functions */
 555
 556 /* 2048 is the max value we can use here */
 557 #define ARMJTAGEW_TAP_BUFFER_SIZE 2048
 558
 559 static int tap_length;
 560 static u8 tms_buffer[ARMJTAGEW_TAP_BUFFER_SIZE];
 561 static u8 tdi_buffer[ARMJTAGEW_TAP_BUFFER_SIZE];
 562 static u8 tdo_buffer[ARMJTAGEW_TAP_BUFFER_SIZE];
 563
 564 typedef struct
 565 {
 566         int first;      /* First bit position in tdo_buffer to read */
 567         int length; /* Number of bits to read */
 568         scan_command_t *command; /* Corresponding scan command */
 569         u8 *buffer;
 570 } pending_scan_result_t;
 571
 572 #define MAX_PENDING_SCAN_RESULTS 256
 573
 574 static int pending_scan_results_length;
 575 static pending_scan_result_t pending_scan_results_buffer[MAX_PENDING_SCAN_RESULTS];
 576
 577 static int last_tms;
 578
 579 static void armjtagew_tap_init(void)
 580 {
 581         tap_length = 0;
 582         pending_scan_results_length = 0;
 583 }
 584
 585 static void armjtagew_tap_ensure_space(int scans, int bits)
 586 {
 587         int available_scans = MAX_PENDING_SCAN_RESULTS - pending_scan_results_length;
 588         int available_bits = ARMJTAGEW_TAP_BUFFER_SIZE * 8 - tap_length;
 589
 590         if (scans > available_scans || bits > available_bits)
 591         {
 592                 armjtagew_tap_execute();
 593         }
 594 }
 595
 596 static void armjtagew_tap_append_step(int tms, int tdi)
 597 {
 598         last_tms = tms;
 599         int index = tap_length / 8;
 600
 601         if (index < ARMJTAGEW_TAP_BUFFER_SIZE)
 602         {
 603                 int bit_index = tap_length % 8;
 604                 u8 bit = 1 << bit_index;
 605
 606                 if (tms)
 607                 {
 608                         tms_buffer[index] |= bit;
 609                 }
 610                 else
 611                 {
 612                         tms_buffer[index] &= ~bit;
 613                 }
 614
 615                 if (tdi)
 616                 {
 617                         tdi_buffer[index] |= bit;
 618                 }
 619                 else
 620                 {
 621                         tdi_buffer[index] &= ~bit;
 622                 }
 623
 624                 tap_length++;
 625         }
 626         else
 627         {
 628                 LOG_ERROR("armjtagew_tap_append_step, overflow");
 629         }
 630 }
 631
 632 void armjtagew_tap_append_scan(int length, u8 *buffer, scan_command_t *command)
 633 {
 634         pending_scan_result_t *pending_scan_result = &pending_scan_results_buffer[pending_scan_results_length];
 635         int i;
 636
 637         pending_scan_result->first = tap_length;
 638         pending_scan_result->length = length;
 639         pending_scan_result->command = command;
 640         pending_scan_result->buffer = buffer;
 641
 642         for (i = 0; i < length; i++)
 643         {
 644                 armjtagew_tap_append_step((i < length-1 ? 0 : 1), (buffer[i/8] >> (i%8)) & 1);
 645         }
 646         pending_scan_results_length++;
 647 }
 648
 649 /* Pad and send a tap sequence to the device, and receive the answer.
 650  * For the purpose of padding we assume that we are in idle or pause state. */
 651 static int armjtagew_tap_execute(void)
 652 {
 653         int byte_length;
 654         int tms_offset;
 655         int tdi_offset;
 656         int i;
 657         int result;
 658
 659         if (tap_length > 0)
 660         {
 661                 /* Pad last byte so that tap_length is divisible by 8 */
 662                 while (tap_length % 8 != 0)
 663                 {
 664                         /* More of the last TMS value keeps us in the same state,
 665                          * analogous to free-running JTAG interfaces. */
 666                         armjtagew_tap_append_step(last_tms, 0);
 667                 }
 668
 669                 byte_length = tap_length / 8;
 670
 671                 usb_out_buffer[0] = CMD_TAP_SHIFT;
 672                 buf_set_u32(usb_out_buffer+1, 0, 16, byte_length);
 673
 674                 tms_offset = 3;
 675                 for (i = 0; i < byte_length; i++)
 676                 {
 677                         usb_out_buffer[tms_offset + i] = flip_u32(tms_buffer[i],8);
 678                 }
 679
 680                 tdi_offset = tms_offset + byte_length;
 681                 for (i = 0; i < byte_length; i++)
 682                 {
 683                         usb_out_buffer[tdi_offset + i] = flip_u32(tdi_buffer[i],8);
 684                 }
 685
 686                 result = armjtagew_usb_message(armjtagew_jtag_handle, 3 + 2 * byte_length, byte_length + 4);
 687
 688                 if (result == 0)
 689                 {
 690                         int stat;
 691
 692                         stat = (int)buf_get_u32(usb_in_buffer + byte_length, 0, 32);
 693                         if(stat) {
 694                                 LOG_ERROR("armjtagew_tap_execute, emulator returned error code %d for a CMD_TAP_SHIFT command", stat);
 695                                 return ERROR_JTAG_QUEUE_FAILED;
 696                         }
 697
 698                         for (i = 0; i < byte_length; i++)
 699                         {
 700                                 tdo_buffer[i] = flip_u32(usb_in_buffer[i],8);
 701                         }
 702
 703                         for (i = 0; i < pending_scan_results_length; i++)
 704                         {
 705                                 pending_scan_result_t *pending_scan_result = &pending_scan_results_buffer[i];
 706                                 u8 *buffer = pending_scan_result->buffer;
 707                                 int length = pending_scan_result->length;
 708                                 int first = pending_scan_result->first;
 709                                 scan_command_t *command = pending_scan_result->command;
 710
 711                                 /* Copy to buffer */
 712                                 buf_set_buf(tdo_buffer, first, buffer, 0, length);
 713
 714                                 DEBUG_JTAG_IO("pending scan result, length = %d", length);
 715
 716 #ifdef _DEBUG_USB_COMMS_
 717                                 armjtagew_debug_buffer(buffer, byte_length);
 718 #endif
 719
 720                                 if (jtag_read_buffer(buffer, command) != ERROR_OK)
 721                                 {
 722                                         armjtagew_tap_init();
 723                                         return ERROR_JTAG_QUEUE_FAILED;
 724                                 }
 725
 726                                 if (pending_scan_result->buffer != NULL)
 727                                 {
 728                                         free(pending_scan_result->buffer);
 729                                 }
 730                         }
 731                 }
 732                 else
 733                 {
 734                         LOG_ERROR("armjtagew_tap_execute, wrong result %d, expected %d", result, byte_length);
 735                         return ERROR_JTAG_QUEUE_FAILED;
 736                 }
 737
 738                 armjtagew_tap_init();
 739         }
 740
 741         return ERROR_OK;
 742 }
 743
 744 /*****************************************************************************/
 745 /* JLink USB low-level functions */
 746
 747 static armjtagew_jtag_t* armjtagew_usb_open()
 748 {
 749         struct usb_bus *busses;
 750         struct usb_bus *bus;
 751         struct usb_device *dev;
 752
 753         armjtagew_jtag_t *result;
 754
 755         result = (armjtagew_jtag_t*) malloc(sizeof(armjtagew_jtag_t));
 756
 757         usb_init();
 758         usb_find_busses();
 759         usb_find_devices();
 760
 761         busses = usb_get_busses();
 762
 763         /* find armjtagew_jtag device in usb bus */
 764
 765         for (bus = busses; bus; bus = bus->next)
 766         {
 767                 for (dev = bus->devices; dev; dev = dev->next)
 768                 {
 769                         if ((dev->descriptor.idVendor == USB_VID) && (dev->descriptor.idProduct == USB_PID))
 770                         {
 771                                 result->usb_handle = usb_open(dev);
 772
 773 #if 0
 774                                 /* usb_set_configuration required under win32 */
 775                                 usb_set_configuration(result->usb_handle, dev->config[0].bConfigurationValue);
 776 #endif
 777                                 usb_claim_interface(result->usb_handle, 0);
 778
 779 #if 0
 780                                 /*
 781                                  * This makes problems under Mac OS X. And is not needed
 782                                  * under Windows. Hopefully this will not break a linux build
 783                                  */
 784                                 usb_set_altinterface(result->usb_handle, 0);
 785 #endif
 786                                 return result;
 787                         }
 788                 }
 789         }
 790
 791         free(result);
 792         return NULL;
 793 }
 794
 795 static void armjtagew_usb_close(armjtagew_jtag_t *armjtagew_jtag)
 796 {
 797         usb_close(armjtagew_jtag->usb_handle);
 798         free(armjtagew_jtag);
 799 }
 800
 801 /* Send a message and receive the reply. */
 802 static int armjtagew_usb_message(armjtagew_jtag_t *armjtagew_jtag, int out_length, int in_length)
 803 {
 804         int result;
 805
 806         result = armjtagew_usb_write(armjtagew_jtag, out_length);
 807         if (result == out_length)
 808         {
 809                 result = armjtagew_usb_read(armjtagew_jtag, in_length);
 810                 if (result != in_length)
 811                 {
 812                         LOG_ERROR("usb_bulk_read failed (requested=%d, result=%d)", in_length, result);
 813                         return -1;
 814                 }
 815         }
 816         else
 817         {
 818                 LOG_ERROR("usb_bulk_write failed (requested=%d, result=%d)", out_length, result);
 819                 return -1;
 820         }
 821         return 0;
 822 }
 823
 824 /* Write data from out_buffer to USB. */
 825 static int armjtagew_usb_write(armjtagew_jtag_t *armjtagew_jtag, int out_length)
 826 {
 827         int result;
 828
 829         if (out_length > ARMJTAGEW_OUT_BUFFER_SIZE)
 830         {
 831                 LOG_ERROR("armjtagew_jtag_write illegal out_length=%d (max=%d)", out_length, ARMJTAGEW_OUT_BUFFER_SIZE);
 832                 return -1;
 833         }
 834
 835         result = usb_bulk_write(armjtagew_jtag->usb_handle, ARMJTAGEW_EPT_BULK_OUT, \
 836                 (char*)usb_out_buffer, out_length, ARMJTAGEW_USB_TIMEOUT);
 837
 838         DEBUG_JTAG_IO("armjtagew_usb_write, out_length = %d, result = %d", out_length, result);
 839
 840 #ifdef _DEBUG_USB_COMMS_
 841         armjtagew_debug_buffer(usb_out_buffer, out_length);
 842 #endif
 843         return result;
 844 }
 845
 846 /* Read data from USB into in_buffer. */
 847 static int armjtagew_usb_read(armjtagew_jtag_t *armjtagew_jtag, int exp_in_length)
 848 {
 849         int result = usb_bulk_read(armjtagew_jtag->usb_handle, ARMJTAGEW_EPT_BULK_IN, \
 850                 (char*)usb_in_buffer, exp_in_length, ARMJTAGEW_USB_TIMEOUT);
 851
 852         DEBUG_JTAG_IO("armjtagew_usb_read, result = %d", result);
 853
 854 #ifdef _DEBUG_USB_COMMS_
 855         armjtagew_debug_buffer(usb_in_buffer, result);
 856 #endif
 857         return result;
 858 }
 859
 860
 861 #ifdef _DEBUG_USB_COMMS_
 862 #define BYTES_PER_LINE  16
 863
 864 static void armjtagew_debug_buffer(u8 *buffer, int length)
 865 {
 866         char line[81];
 867         char s[4];
 868         int i;
 869         int j;
 870
 871         for (i = 0; i < length; i += BYTES_PER_LINE)
 872         {
 873                 snprintf(line, 5, "%04x", i);
 874                 for (j = i; j < i + BYTES_PER_LINE && j < length; j++)
 875                 {
 876                         snprintf(s, 4, " %02x", buffer[j]);
 877                         strcat(line, s);
 878                 }
 879                 LOG_DEBUG("%s", line);
 880         }
 881 }
 882 #endif
 883