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 #define VID 0x1366
  38 #define PID 0x0101
  39
  40 #define JLINK_WRITE_ENDPOINT    0x02
  41 #define JLINK_READ_ENDPOINT             0x81
  42
  43 #define JLINK_USB_TIMEOUT               1000
  44
  45 // See Section 1.3.2 of the Segger JLink USB protocol manual
  46 #define JLINK_IN_BUFFER_SIZE                    2048
  47 #define JLINK_OUT_BUFFER_SIZE                   2*2048+4
  48 #define JLINK_EMU_RESULT_BUFFER_SIZE    64
  49
  50 /* Global USB buffers */
  51 static u8 usb_in_buffer[JLINK_IN_BUFFER_SIZE];
  52 static u8 usb_out_buffer[JLINK_OUT_BUFFER_SIZE];
  53 static u8 usb_emu_result_buffer[JLINK_EMU_RESULT_BUFFER_SIZE];
  54
  55 /* Constants for JLink command */
  56 #define EMU_CMD_VERSION                 0x01
  57 #define EMU_CMD_SET_SPEED               0x05
  58 #define EMU_CMD_GET_STATE               0x07
  59 #define EMU_CMD_HW_JTAG3                0xcf
  60 #define EMU_CMD_GET_MAX_MEM_BLOCK   0xd4
  61 #define EMU_CMD_HW_RESET0               0xdc
  62 #define EMU_CMD_HW_RESET1               0xdd
  63 #define EMU_CMD_HW_TRST0                0xde
  64 #define EMU_CMD_HW_TRST1                0xdf
  65 #define EMU_CMD_GET_CAPS                0xe8
  66
  67 /* max speed 12MHz v5.0 jlink */
  68 #define JLINK_MAX_SPEED 12000
  69
  70 /* External interface functions */
  71 static int jlink_execute_queue(void);
  72 static int jlink_speed(int speed);
  73 static int jlink_speed_div(int speed, int* khz);
  74 static int jlink_khz(int khz, int *jtag_speed);
  75 static int jlink_register_commands(struct command_context_s *cmd_ctx);
  76 static int jlink_init(void);
  77 static int jlink_quit(void);
  78
  79 /* CLI command handler functions */
  80 static int jlink_handle_jlink_info_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
  81
  82 /* Queue command functions */
  83 static void jlink_end_state(tap_state_t state);
  84 static void jlink_state_move(void);
  85 static void jlink_path_move(int num_states, tap_state_t *path);
  86 static void jlink_runtest(int num_cycles);
  87 static void jlink_scan(int ir_scan, enum scan_type type, u8 *buffer, int scan_size, scan_command_t *command);
  88 static void jlink_reset(int trst, int srst);
  89 static void jlink_simple_command(u8 command);
  90 static int jlink_get_status(void);
  91
  92 /* J-Link tap buffer functions */
  93 static void jlink_tap_init(void);
  94 static int jlink_tap_execute(void);
  95 static void jlink_tap_ensure_space(int scans, int bits);
  96 static void jlink_tap_append_step(int tms, int tdi);
  97 static void jlink_tap_append_scan(int length, u8 *buffer, scan_command_t *command);
  98
  99 /* Jlink lowlevel functions */
 100 typedef struct jlink_jtag
 101 {
 102         struct usb_dev_handle* usb_handle;
 103 } jlink_jtag_t;
 104
 105 static jlink_jtag_t *jlink_usb_open(void);
 106 static void jlink_usb_close(jlink_jtag_t *jlink_jtag);
 107 static int jlink_usb_message(jlink_jtag_t *jlink_jtag, int out_length, int in_length);
 108 static int jlink_usb_write(jlink_jtag_t *jlink_jtag, int out_length);
 109 static int jlink_usb_read(jlink_jtag_t *jlink_jtag, int expected_size);
 110 static int jlink_usb_read_emu_result(jlink_jtag_t *jlink_jtag);
 111
 112 /* helper functions */
 113 static int jlink_get_version_info(void);
 114
 115 #ifdef _DEBUG_USB_COMMS_
 116 static void jlink_debug_buffer(u8 *buffer, int length);
 117 #endif
 118
 119 static enum tap_state jlink_last_state = TAP_RESET;
 120
 121 static jlink_jtag_t* jlink_jtag_handle;
 122
 123 /***************************************************************************/
 124 /* External interface implementation */
 125
 126 jtag_interface_t jlink_interface =
 127 {
 128         .name = "jlink",
 129         .execute_queue = jlink_execute_queue,
 130         .speed = jlink_speed,
 131         .speed_div = jlink_speed_div,
 132         .khz = jlink_khz,
 133         .register_commands = jlink_register_commands,
 134         .init = jlink_init,
 135         .quit = jlink_quit
 136 };
 137
 138 static void jlink_execute_end_state(jtag_command_t *cmd)
 139 {
 140         DEBUG_JTAG_IO("end_state: %i", cmd->cmd.end_state->end_state);
 141
 142         if (cmd->cmd.end_state->end_state != TAP_INVALID)
 143                 jlink_end_state(cmd->cmd.end_state->end_state);
 144 }
 145
 146 static void jlink_execute_runtest(jtag_command_t *cmd)
 147 {
 148         DEBUG_JTAG_IO("runtest %i cycles, end in %i",
 149                         cmd->cmd.runtest->num_cycles,
 150                         cmd->cmd.runtest->end_state);
 151
 152         if (cmd->cmd.runtest->end_state != TAP_INVALID)
 153                 jlink_end_state(cmd->cmd.runtest->end_state);
 154
 155         jlink_runtest(cmd->cmd.runtest->num_cycles);
 156 }
 157
 158 static void jlink_execute_statemove(jtag_command_t *cmd)
 159 {
 160         DEBUG_JTAG_IO("statemove end in %i", cmd->cmd.statemove->end_state);
 161
 162         if (cmd->cmd.statemove->end_state != TAP_INVALID)
 163         {
 164                 jlink_end_state(cmd->cmd.statemove->end_state);
 165         }
 166         jlink_state_move();
 167 }
 168
 169 static void jlink_execute_pathmove(jtag_command_t *cmd)
 170 {
 171         DEBUG_JTAG_IO("pathmove: %i states, end in %i",
 172                 cmd->cmd.pathmove->num_states,
 173                 cmd->cmd.pathmove->path[cmd->cmd.pathmove->num_states - 1]);
 174
 175         jlink_path_move(cmd->cmd.pathmove->num_states,
 176                         cmd->cmd.pathmove->path);
 177 }
 178
 179 static void jlink_execute_scan(jtag_command_t *cmd)
 180 {
 181         int scan_size;
 182         enum scan_type type;
 183         u8 *buffer;
 184
 185         DEBUG_JTAG_IO("scan end in %i", cmd->cmd.scan->end_state);
 186
 187         if (cmd->cmd.scan->end_state != TAP_INVALID)
 188                 jlink_end_state(cmd->cmd.scan->end_state);
 189
 190         scan_size = jtag_build_buffer(cmd->cmd.scan, &buffer);
 191         DEBUG_JTAG_IO("scan input, length = %d", scan_size);
 192
 193 #ifdef _DEBUG_USB_COMMS_
 194         jlink_debug_buffer(buffer, (scan_size + 7) / 8);
 195 #endif
 196         type = jtag_scan_type(cmd->cmd.scan);
 197         jlink_scan(cmd->cmd.scan->ir_scan,
 198                         type, buffer, scan_size, cmd->cmd.scan);
 199 }
 200
 201 static void jlink_execute_reset(jtag_command_t *cmd)
 202 {
 203         DEBUG_JTAG_IO("reset trst: %i srst %i",
 204                         cmd->cmd.reset->trst, cmd->cmd.reset->srst);
 205
 206         jlink_tap_execute();
 207
 208         if (cmd->cmd.reset->trst == 1)
 209                 tap_set_state(TAP_RESET);
 210
 211         jlink_reset(cmd->cmd.reset->trst, cmd->cmd.reset->srst);
 212 }
 213
 214 static void jlink_execute_sleep(jtag_command_t *cmd)
 215 {
 216         DEBUG_JTAG_IO("sleep %i", cmd->cmd.sleep->us);
 217         jlink_tap_execute();
 218         jtag_sleep(cmd->cmd.sleep->us);
 219 }
 220
 221 static void jlink_execute_command(jtag_command_t *cmd)
 222 {
 223         switch (cmd->type)
 224         {
 225         case JTAG_END_STATE: jlink_execute_end_state(cmd); break;
 226         case JTAG_RUNTEST:   jlink_execute_runtest(cmd); break;
 227         case JTAG_STATEMOVE: jlink_execute_statemove(cmd); break;
 228         case JTAG_PATHMOVE:  jlink_execute_pathmove(cmd); break;
 229         case JTAG_SCAN:      jlink_execute_scan(cmd); break;
 230         case JTAG_RESET:     jlink_execute_reset(cmd); break;
 231         case JTAG_SLEEP:     jlink_execute_sleep(cmd); break;
 232         default:
 233                 LOG_ERROR("BUG: unknown JTAG command type encountered");
 234                 exit(-1);
 235         }
 236 }
 237
 238 static int jlink_execute_queue(void)
 239 {
 240         jtag_command_t *cmd = jtag_command_queue;
 241
 242         while (cmd != NULL)
 243         {
 244                 jlink_execute_command(cmd);
 245                 cmd = cmd->next;
 246         }
 247
 248         return jlink_tap_execute();
 249 }
 250
 251 /* Sets speed in kHz. */
 252 static int jlink_speed(int speed)
 253 {
 254         int result;
 255
 256         if (speed > JLINK_MAX_SPEED)
 257         {
 258                 LOG_INFO("Ignoring speed request: %dkHz exceeds %dkHz maximum",
 259                                 speed, JLINK_MAX_SPEED);
 260                 return ERROR_OK;
 261         }
 262
 263         /* check for RTCK setting */
 264         if (speed == 0)
 265                 speed = -1;
 266
 267         usb_out_buffer[0] = EMU_CMD_SET_SPEED;
 268         usb_out_buffer[1] = (speed >> 0) & 0xff;
 269         usb_out_buffer[2] = (speed >> 8) & 0xff;
 270
 271         result = jlink_usb_write(jlink_jtag_handle, 3);
 272         if (result != 3)
 273         {
 274                 LOG_ERROR("J-Link setting speed failed (%d)", result);
 275                 return ERROR_JTAG_DEVICE_ERROR;
 276         }
 277
 278         return ERROR_OK;
 279 }
 280
 281 static int jlink_speed_div(int speed, int* khz)
 282 {
 283         *khz = speed;
 284
 285         return ERROR_OK;
 286 }
 287
 288 static int jlink_khz(int khz, int *jtag_speed)
 289 {
 290         *jtag_speed = khz;
 291
 292         return ERROR_OK;
 293 }
 294
 295 static int jlink_register_commands(struct command_context_s *cmd_ctx)
 296 {
 297         register_command(cmd_ctx, NULL, "jlink_info", jlink_handle_jlink_info_command, COMMAND_EXEC,
 298                 "query jlink info");
 299         return ERROR_OK;
 300 }
 301
 302 static int jlink_init(void)
 303 {
 304         int check_cnt;
 305
 306         jlink_jtag_handle = jlink_usb_open();
 307
 308         if (jlink_jtag_handle == 0)
 309         {
 310                 LOG_ERROR("Cannot find jlink Interface! Please check connection and permissions.");
 311                 return ERROR_JTAG_INIT_FAILED;
 312         }
 313
 314         check_cnt = 0;
 315         while (check_cnt < 3)
 316         {
 317                 if (jlink_get_version_info() == ERROR_OK)
 318                 {
 319                         /* attempt to get status */
 320                         jlink_get_status();
 321                         break;
 322                 }
 323
 324                 check_cnt++;
 325         }
 326
 327         if (check_cnt == 3)
 328         {
 329                 LOG_INFO("J-Link initial read failed, don't worry");
 330         }
 331
 332         LOG_INFO("J-Link JTAG Interface ready");
 333
 334         jlink_reset(0, 0);
 335         jlink_tap_init();
 336         jlink_speed(jtag_speed);
 337
 338         return ERROR_OK;
 339 }
 340
 341 static int jlink_quit(void)
 342 {
 343         jlink_usb_close(jlink_jtag_handle);
 344         return ERROR_OK;
 345 }
 346
 347 /***************************************************************************/
 348 /* Queue command implementations */
 349
 350 static void jlink_end_state(tap_state_t state)
 351 {
 352         if (tap_is_state_stable(state))
 353         {
 354                 tap_set_end_state(state);
 355         }
 356         else
 357         {
 358                 LOG_ERROR("BUG: %i is not a valid end state", state);
 359                 exit(-1);
 360         }
 361 }
 362
 363 /* Goes to the end state. */
 364 static void jlink_state_move(void)
 365 {
 366         int i;
 367         int tms = 0;
 368         u8 tms_scan = tap_get_tms_path(tap_get_state(), tap_get_end_state());
 369
 370         for (i = 0; i < 7; i++)
 371         {
 372                 tms = (tms_scan >> i) & 1;
 373                 jlink_tap_append_step(tms, 0);
 374         }
 375
 376         tap_set_state(tap_get_end_state());
 377 }
 378
 379 static void jlink_path_move(int num_states, tap_state_t *path)
 380 {
 381         int i;
 382
 383         for (i = 0; i < num_states; i++)
 384         {
 385                 if (path[i] == tap_state_transition(tap_get_state(), false))
 386                 {
 387                         jlink_tap_append_step(0, 0);
 388                 }
 389                 else if (path[i] == tap_state_transition(tap_get_state(), true))
 390                 {
 391                         jlink_tap_append_step(1, 0);
 392                 }
 393                 else
 394                 {
 395                         LOG_ERROR("BUG: %s -> %s isn't a valid TAP transition", tap_state_name(tap_get_state()), tap_state_name(path[i]));
 396                         exit(-1);
 397                 }
 398
 399                 tap_set_state(path[i]);
 400         }
 401
 402         tap_set_end_state(tap_get_state());
 403 }
 404
 405 static void jlink_runtest(int num_cycles)
 406 {
 407         int i;
 408
 409         tap_state_t saved_end_state = tap_get_end_state();
 410
 411         /* only do a state_move when we're not already in IDLE */
 412         if (tap_get_state() != TAP_IDLE)
 413         {
 414                 jlink_end_state(TAP_IDLE);
 415                 jlink_state_move();
 416         }
 417
 418         /* execute num_cycles */
 419         for (i = 0; i < num_cycles; i++)
 420         {
 421                 jlink_tap_append_step(0, 0);
 422         }
 423
 424         /* finish in end_state */
 425         jlink_end_state(saved_end_state);
 426         if (tap_get_state() != tap_get_end_state())
 427         {
 428                 jlink_state_move();
 429         }
 430 }
 431
 432 static void jlink_scan(int ir_scan, enum scan_type type, u8 *buffer, int scan_size, scan_command_t *command)
 433 {
 434         tap_state_t saved_end_state;
 435
 436         jlink_tap_ensure_space(1, scan_size + 8);
 437
 438         saved_end_state = tap_get_end_state();
 439
 440         /* Move to appropriate scan state */
 441         jlink_end_state(ir_scan ? TAP_IRSHIFT : TAP_DRSHIFT);
 442
 443         /* Only move if we're not already there */
 444         if (tap_get_state() != tap_get_end_state())
 445                 jlink_state_move();
 446
 447         jlink_end_state(saved_end_state);
 448
 449         /* Scan */
 450         jlink_tap_append_scan(scan_size, buffer, command);
 451
 452         /* We are in Exit1, go to Pause */
 453         jlink_tap_append_step(0, 0);
 454
 455         tap_set_state(ir_scan ? TAP_IRPAUSE : TAP_DRPAUSE);
 456
 457         if (tap_get_state() != tap_get_end_state())
 458         {
 459                 jlink_state_move();
 460         }
 461 }
 462
 463 static void jlink_reset(int trst, int srst)
 464 {
 465         LOG_DEBUG("trst: %i, srst: %i", trst, srst);
 466
 467         /* Signals are active low */
 468         if (srst == 0)
 469         {
 470                 jlink_simple_command(EMU_CMD_HW_RESET1);
 471                 jlink_end_state(TAP_RESET);
 472                 jlink_state_move();
 473         }
 474         else if (srst == 1)
 475         {
 476                 jlink_simple_command(EMU_CMD_HW_RESET0);
 477         }
 478
 479         if (trst == 0)
 480         {
 481                 jlink_simple_command(EMU_CMD_HW_TRST1);
 482                 jlink_end_state(TAP_RESET);
 483                 jlink_state_move();
 484         }
 485         else if (trst == 1)
 486         {
 487                 jlink_simple_command(EMU_CMD_HW_TRST0);
 488         }
 489 }
 490
 491 static void jlink_simple_command(u8 command)
 492 {
 493         int result;
 494
 495         DEBUG_JTAG_IO("0x%02x", command);
 496
 497         usb_out_buffer[0] = command;
 498         result = jlink_usb_write(jlink_jtag_handle, 1);
 499
 500         if (result != 1)
 501         {
 502                 LOG_ERROR("J-Link command 0x%02x failed (%d)", command, result);
 503         }
 504 }
 505
 506 static int jlink_get_status(void)
 507 {
 508         int result;
 509
 510         jlink_simple_command(EMU_CMD_GET_STATE);
 511
 512         result = jlink_usb_read(jlink_jtag_handle, 8);
 513         if (result != 8)
 514         {
 515                 LOG_ERROR("J-Link command EMU_CMD_GET_STATE failed (%d)\n", result);
 516                 return ERROR_JTAG_DEVICE_ERROR;
 517         }
 518
 519         int vref = usb_in_buffer[0] + (usb_in_buffer[1] << 8);
 520         LOG_INFO("Vref = %d.%d TCK = %d TDI = %d TDO = %d TMS = %d SRST = %d TRST = %d\n", \
 521                 vref / 1000, vref % 1000, \
 522                 usb_in_buffer[2], usb_in_buffer[3], usb_in_buffer[4], \
 523                 usb_in_buffer[5], usb_in_buffer[6], usb_in_buffer[7]);
 524
 525         if (vref < 1500)
 526                 LOG_ERROR("Vref too low. Check Target Power\n");
 527
 528         return ERROR_OK;
 529 }
 530
 531 static int jlink_get_version_info(void)
 532 {
 533         int result;
 534         int len;
 535         u32 jlink_caps, jlink_max_size;
 536
 537         /* query hardware version */
 538         jlink_simple_command(EMU_CMD_VERSION);
 539
 540         result = jlink_usb_read(jlink_jtag_handle, 2);
 541         if (2 != result)
 542         {
 543                 LOG_ERROR("J-Link command EMU_CMD_VERSION failed (%d)\n", result);
 544                 return ERROR_JTAG_DEVICE_ERROR;
 545         }
 546
 547         len = buf_get_u32(usb_in_buffer, 0, 16);
 548         result = jlink_usb_read(jlink_jtag_handle, len);
 549         if (result != len)
 550         {
 551                 LOG_ERROR("J-Link command EMU_CMD_VERSION failed (%d)\n", result);
 552                 return ERROR_JTAG_DEVICE_ERROR;
 553         }
 554
 555         usb_in_buffer[result] = 0;
 556         LOG_INFO("%s", (char *)usb_in_buffer);
 557
 558         /* query hardware capabilities */
 559         jlink_simple_command(EMU_CMD_GET_CAPS);
 560
 561         result = jlink_usb_read(jlink_jtag_handle, 4);
 562         if (4 != result)
 563         {
 564                 LOG_ERROR("J-Link command EMU_CMD_GET_CAPS failed (%d)\n", result);
 565                 return ERROR_JTAG_DEVICE_ERROR;
 566         }
 567
 568         jlink_caps = buf_get_u32(usb_in_buffer, 0, 32);
 569         LOG_INFO("JLink caps 0x%x", jlink_caps);
 570
 571
 572         /* query hardware maximum memory block */
 573         jlink_simple_command(EMU_CMD_GET_MAX_MEM_BLOCK);
 574
 575         result = jlink_usb_read(jlink_jtag_handle, 4);
 576         if (4 != result)
 577         {
 578                 LOG_ERROR("J-Link command EMU_CMD_GET_MAX_MEM_BLOCK failed (%d)\n", result);
 579                 return ERROR_JTAG_DEVICE_ERROR;
 580         }
 581
 582         jlink_max_size = buf_get_u32(usb_in_buffer, 0, 32);
 583         LOG_INFO("JLink max mem block %i", jlink_max_size);
 584
 585
 586         return ERROR_OK;
 587 }
 588
 589 static int jlink_handle_jlink_info_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 590 {
 591         if (jlink_get_version_info() == ERROR_OK)
 592         {
 593                 /* attempt to get status */
 594                 jlink_get_status();
 595         }
 596
 597         return ERROR_OK;
 598 }
 599
 600 /***************************************************************************/
 601 /* J-Link tap functions */
 602
 603 /* 2048 is the max value we can use here */
 604 #define JLINK_TAP_BUFFER_SIZE 2048
 605
 606 static unsigned tap_length;
 607 static u8 tms_buffer[JLINK_TAP_BUFFER_SIZE];
 608 static u8 tdi_buffer[JLINK_TAP_BUFFER_SIZE];
 609 static u8 tdo_buffer[JLINK_TAP_BUFFER_SIZE];
 610
 611 typedef struct
 612 {
 613         int first;      /* First bit position in tdo_buffer to read */
 614         int length; /* Number of bits to read */
 615         scan_command_t *command; /* Corresponding scan command */
 616         u8 *buffer;
 617 } pending_scan_result_t;
 618
 619 #define MAX_PENDING_SCAN_RESULTS 256
 620
 621 static int pending_scan_results_length;
 622 static pending_scan_result_t pending_scan_results_buffer[MAX_PENDING_SCAN_RESULTS];
 623
 624 static void jlink_tap_init(void)
 625 {
 626         tap_length = 0;
 627         pending_scan_results_length = 0;
 628 }
 629
 630 static void jlink_tap_ensure_space(int scans, int bits)
 631 {
 632         int available_scans = MAX_PENDING_SCAN_RESULTS - pending_scan_results_length;
 633         int available_bits = JLINK_TAP_BUFFER_SIZE * 8 - tap_length;
 634
 635         if (scans > available_scans || bits > available_bits)
 636         {
 637                 jlink_tap_execute();
 638         }
 639 }
 640
 641 static void jlink_tap_append_step(int tms, int tdi)
 642 {
 643         int index = tap_length / 8;
 644
 645         if (index >= JLINK_TAP_BUFFER_SIZE)
 646         {
 647                 LOG_ERROR("jlink_tap_append_step: overflow");
 648                 exit(-1);
 649         }
 650
 651         int bit_index = tap_length % 8;
 652         u8 bit = 1 << bit_index;
 653
 654         // we do not pad TMS, so be sure to initialize all bits
 655         if (0 == bit_index)
 656                 tms_buffer[index] = tdi_buffer[index] = 0;
 657
 658         if (tms)
 659                 tms_buffer[index] |= bit;
 660         else
 661                 tms_buffer[index] &= ~bit;
 662
 663         if (tdi)
 664                 tdi_buffer[index] |= bit;
 665         else
 666                 tdi_buffer[index] &= ~bit;
 667
 668         tap_length++;
 669 }
 670
 671 static void jlink_tap_append_scan(int length, u8 *buffer, scan_command_t *command)
 672 {
 673         pending_scan_result_t *pending_scan_result =
 674                 &pending_scan_results_buffer[pending_scan_results_length];
 675         int i;
 676
 677         pending_scan_result->first = tap_length;
 678         pending_scan_result->length = length;
 679         pending_scan_result->command = command;
 680         pending_scan_result->buffer = buffer;
 681
 682         for (i = 0; i < length; i++)
 683         {
 684                 int tms = i < length - 1 ? 0 : 1;
 685                 int tdi = buffer[i / 8] & (1 << (i % 8));
 686                 jlink_tap_append_step(tms, tdi);
 687         }
 688         pending_scan_results_length++;
 689 }
 690
 691 /* Pad and send a tap sequence to the device, and receive the answer.
 692  * For the purpose of padding we assume that we are in idle or pause state. */
 693 static int jlink_tap_execute(void)
 694 {
 695         int byte_length;
 696         int i;
 697         int result;
 698
 699         if (!tap_length)
 700                 return ERROR_OK;
 701
 702         // number of full bytes (plus one if some would be left over)
 703         byte_length = TAP_SCAN_BYTES(tap_length);
 704
 705         usb_out_buffer[0] = EMU_CMD_HW_JTAG3;
 706         usb_out_buffer[1] = 0;
 707         usb_out_buffer[2] = (tap_length >> 0) & 0xff;
 708         usb_out_buffer[3] = (tap_length >> 8) & 0xff;
 709         memcpy(usb_out_buffer + 4, tms_buffer, byte_length);
 710         memcpy(usb_out_buffer + 4 + byte_length, tdi_buffer, byte_length);
 711
 712         jlink_last_state = jtag_debug_state_machine(tms_buffer, tdi_buffer,
 713                         tap_length, jlink_last_state);
 714
 715         result = jlink_usb_message(jlink_jtag_handle, 4 + 2 * byte_length, byte_length);
 716         if (result != byte_length)
 717         {
 718                 LOG_ERROR("jlink_tap_execute, wrong result %d (expected %d)", result, byte_length);
 719                 jlink_tap_init();
 720                 return ERROR_JTAG_QUEUE_FAILED;
 721         }
 722
 723         memcpy(tdo_buffer, usb_in_buffer, byte_length);
 724
 725         for (i = 0; i < pending_scan_results_length; i++)
 726         {
 727                 pending_scan_result_t *pending_scan_result = &pending_scan_results_buffer[i];
 728                 u8 *buffer = pending_scan_result->buffer;
 729                 int length = pending_scan_result->length;
 730                 int first = pending_scan_result->first;
 731                 scan_command_t *command = pending_scan_result->command;
 732
 733                 /* Copy to buffer */
 734                 buf_set_buf(tdo_buffer, first, buffer, 0, length);
 735
 736                 DEBUG_JTAG_IO("pending scan result, length = %d", length);
 737
 738 #ifdef _DEBUG_USB_COMMS_
 739                 jlink_debug_buffer(buffer, byte_length);
 740 #endif
 741
 742                 if (jtag_read_buffer(buffer, command) != ERROR_OK)
 743                 {
 744                         jlink_tap_init();
 745                         return ERROR_JTAG_QUEUE_FAILED;
 746                 }
 747
 748                 if (pending_scan_result->buffer != NULL)
 749                 {
 750                         free(pending_scan_result->buffer);
 751                 }
 752         }
 753
 754         jlink_tap_init();
 755         return ERROR_OK;
 756 }
 757
 758 /*****************************************************************************/
 759 /* JLink USB low-level functions */
 760
 761 static jlink_jtag_t* jlink_usb_open()
 762 {
 763         struct usb_bus *busses;
 764         struct usb_bus *bus;
 765         struct usb_device *dev;
 766
 767         jlink_jtag_t *result;
 768
 769         result = (jlink_jtag_t*) malloc(sizeof(jlink_jtag_t));
 770
 771         usb_init();
 772         usb_find_busses();
 773         usb_find_devices();
 774
 775         busses = usb_get_busses();
 776
 777         /* find jlink_jtag device in usb bus */
 778
 779         for (bus = busses; bus; bus = bus->next)
 780         {
 781                 for (dev = bus->devices; dev; dev = dev->next)
 782                 {
 783                         if ((dev->descriptor.idVendor == VID) && (dev->descriptor.idProduct == PID))
 784                         {
 785                                 result->usb_handle = usb_open(dev);
 786
 787                                 /* usb_set_configuration required under win32 */
 788                                 usb_set_configuration(result->usb_handle, dev->config[0].bConfigurationValue);
 789                                 usb_claim_interface(result->usb_handle, 0);
 790
 791 #if 0
 792                                 /*
 793                                  * This makes problems under Mac OS X. And is not needed
 794                                  * under Windows. Hopefully this will not break a linux build
 795                                  */
 796                                 usb_set_altinterface(result->usb_handle, 0);
 797 #endif
 798                                 return result;
 799                         }
 800                 }
 801         }
 802
 803         free(result);
 804         return NULL;
 805 }
 806
 807 static void jlink_usb_close(jlink_jtag_t *jlink_jtag)
 808 {
 809         usb_close(jlink_jtag->usb_handle);
 810         free(jlink_jtag);
 811 }
 812
 813 /* Send a message and receive the reply. */
 814 static int jlink_usb_message(jlink_jtag_t *jlink_jtag, int out_length, int in_length)
 815 {
 816         int result;
 817         int result2;
 818
 819         result = jlink_usb_write(jlink_jtag, out_length);
 820         if (result != out_length)
 821         {
 822                 LOG_ERROR("usb_bulk_write failed (requested=%d, result=%d)",
 823                                 out_length, result);
 824                 return ERROR_JTAG_DEVICE_ERROR;
 825         }
 826
 827         result = jlink_usb_read(jlink_jtag, in_length);
 828         if ((result != in_length) && (result != (in_length + 1)))
 829         {
 830                 LOG_ERROR("usb_bulk_read failed (requested=%d, result=%d)",
 831                                 in_length, result);
 832                 return ERROR_JTAG_DEVICE_ERROR;
 833         }
 834
 835         if (result == in_length)
 836         {
 837                 /* Must read the result from the EMU too */
 838                 result2 = jlink_usb_read_emu_result(jlink_jtag);
 839                 if (1 != result2)
 840                 {
 841                         LOG_ERROR("jlink_usb_read_emu_result failed "
 842                                 "(requested=1, result=%d)", result2);
 843                         return ERROR_JTAG_DEVICE_ERROR;
 844                 }
 845
 846                 /* Check the result itself */
 847                 result2 = usb_emu_result_buffer[0];
 848         }
 849         else
 850         {
 851                 /* Save the result, then remove it from return value */
 852                 result2 = usb_in_buffer[result--];
 853         }
 854
 855         if (result2)
 856         {
 857                 LOG_ERROR("jlink_usb_message failed with result=%d)", result2);
 858                 return ERROR_JTAG_DEVICE_ERROR;
 859         }
 860
 861         return result;
 862 }
 863
 864 /* calls the given usb_bulk_* function, allowing for the data to trickle in with some timeouts  */
 865 static int usb_bulk_with_retries(
 866                 int (*f)(usb_dev_handle *, int, char *, int, int),
 867                 usb_dev_handle *dev, int ep,
 868                 char *bytes, int size, int timeout)
 869 {
 870         int rc = 0, tries = 3, this_size;
 871
 872         while (tries && size) {
 873
 874                 this_size = f(dev, ep, bytes, size, timeout);
 875                 if (this_size > 0) {
 876
 877                         size -= this_size;
 878                         rc += this_size;
 879                         bytes += this_size;
 880
 881                 } else
 882                         tries --;
 883         }
 884         return rc;
 885 }
 886
 887 static int wrap_usb_bulk_write(usb_dev_handle *dev, int ep,
 888                                char *buff, int size, int timeout)
 889 {
 890         /* usb_bulk_write() takes const char *buff */
 891         return usb_bulk_write(dev, ep, buff, size, timeout);
 892 }
 893
 894 static inline int usb_bulk_write_ex(usb_dev_handle *dev, int ep,
 895                 char *bytes, int size, int timeout)
 896 {
 897         return usb_bulk_with_retries(&wrap_usb_bulk_write,
 898                         dev, ep, bytes, size, timeout);
 899 }
 900
 901 static inline int usb_bulk_read_ex(usb_dev_handle *dev, int ep,
 902                 char *bytes, int size, int timeout)
 903 {
 904         return usb_bulk_with_retries(&usb_bulk_read,
 905                         dev, ep, bytes, size, timeout);
 906 }
 907
 908 /* Write data from out_buffer to USB. */
 909 static int jlink_usb_write(jlink_jtag_t *jlink_jtag, int out_length)
 910 {
 911         int result;
 912
 913         if (out_length > JLINK_OUT_BUFFER_SIZE)
 914         {
 915                 LOG_ERROR("jlink_jtag_write illegal out_length=%d (max=%d)", out_length, JLINK_OUT_BUFFER_SIZE);
 916                 return -1;
 917         }
 918
 919         result = usb_bulk_write_ex(jlink_jtag->usb_handle, JLINK_WRITE_ENDPOINT,
 920                 (char *)usb_out_buffer, out_length, JLINK_USB_TIMEOUT);
 921
 922         DEBUG_JTAG_IO("jlink_usb_write, out_length = %d, result = %d", out_length, result);
 923
 924 #ifdef _DEBUG_USB_COMMS_
 925         jlink_debug_buffer(usb_out_buffer, out_length);
 926 #endif
 927         return result;
 928 }
 929
 930 /* Read data from USB into in_buffer. */
 931 static int jlink_usb_read(jlink_jtag_t *jlink_jtag, int expected_size)
 932 {
 933         int result = usb_bulk_read_ex(jlink_jtag->usb_handle, JLINK_READ_ENDPOINT,
 934                 (char *)usb_in_buffer, expected_size, JLINK_USB_TIMEOUT);
 935
 936         DEBUG_JTAG_IO("jlink_usb_read, result = %d", result);
 937
 938 #ifdef _DEBUG_USB_COMMS_
 939         jlink_debug_buffer(usb_in_buffer, result);
 940 #endif
 941         return result;
 942 }
 943
 944 /* Read the result from the previous EMU cmd into result_buffer. */
 945 static int jlink_usb_read_emu_result(jlink_jtag_t *jlink_jtag)
 946 {
 947         int result = usb_bulk_read_ex(jlink_jtag->usb_handle, JLINK_READ_ENDPOINT,
 948                 (char *)usb_emu_result_buffer, 1 /* JLINK_EMU_RESULT_BUFFER_SIZE */,
 949                 JLINK_USB_TIMEOUT);
 950
 951         DEBUG_JTAG_IO("jlink_usb_read_result, result = %d", result);
 952
 953 #ifdef _DEBUG_USB_COMMS_
 954         jlink_debug_buffer(usb_emu_result_buffer, result);
 955 #endif
 956         return result;
 957 }
 958
 959 #ifdef _DEBUG_USB_COMMS_
 960 #define BYTES_PER_LINE  16
 961
 962 static void jlink_debug_buffer(u8 *buffer, int length)
 963 {
 964         char line[81];
 965         char s[4];
 966         int i;
 967         int j;
 968
 969         for (i = 0; i < length; i += BYTES_PER_LINE)
 970         {
 971                 snprintf(line, 5, "%04x", i);
 972                 for (j = i; j < i + BYTES_PER_LINE && j < length; j++)
 973                 {
 974                         snprintf(s, 4, " %02x", buffer[j]);
 975                         strcat(line, s);
 976                 }
 977                 LOG_DEBUG("%s", line);
 978         }
 979 }
 980 #endif