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 #define INCLUDE_JTAG_INTERFACE_H
  29 #include "jtag.h"
  30
  31 #include <usb.h>
  32
  33
  34 #define VID 0x1366
  35 #define PID 0x0101
  36
  37 #define JLINK_WRITE_ENDPOINT    0x02
  38 #define JLINK_READ_ENDPOINT             0x81
  39
  40 static unsigned int jlink_write_ep = JLINK_WRITE_ENDPOINT;
  41 static unsigned int jlink_read_ep = JLINK_READ_ENDPOINT;
  42 static unsigned int jlink_hw_jtag_version = 2;
  43
  44 #define JLINK_USB_TIMEOUT               1000
  45
  46 // See Section 1.3.2 of the Segger JLink USB protocol manual
  47 /* 2048 is the max value we can use here */
  48 //#define JLINK_TAP_BUFFER_SIZE 2048
  49 #define JLINK_TAP_BUFFER_SIZE 256
  50 //#define JLINK_TAP_BUFFER_SIZE 384
  51
  52 #define JLINK_IN_BUFFER_SIZE                    2048
  53 #define JLINK_OUT_BUFFER_SIZE                   2*2048+4
  54 #define JLINK_EMU_RESULT_BUFFER_SIZE    64
  55
  56 /* Global USB buffers */
  57 static u8 usb_in_buffer[JLINK_IN_BUFFER_SIZE];
  58 static u8 usb_out_buffer[JLINK_OUT_BUFFER_SIZE];
  59 static u8 usb_emu_result_buffer[JLINK_EMU_RESULT_BUFFER_SIZE];
  60
  61 /* Constants for JLink command */
  62 #define EMU_CMD_VERSION                 0x01
  63 #define EMU_CMD_SET_SPEED               0x05
  64 #define EMU_CMD_GET_STATE               0x07
  65 #define EMU_CMD_HW_CLOCK                        0xc8
  66 #define EMU_CMD_HW_TMS0                         0xc9
  67 #define EMU_CMD_HW_TMS1                         0xca
  68 #define EMU_CMD_HW_JTAG2                0xce
  69 #define EMU_CMD_HW_JTAG3                0xcf
  70 #define EMU_CMD_GET_MAX_MEM_BLOCK       0xd4
  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 #define EMU_CMD_GET_CAPS                0xe8
  76 #define EMU_CMD_GET_HW_VERSION          0xf0
  77
  78 /* bits return from EMU_CMD_GET_CAPS */
  79 #define EMU_CAP_GET_HW_VERSION          1
  80 #define EMU_CAP_GET_MAX_BLOCK_SIZE      11
  81
  82 /* max speed 12MHz v5.0 jlink */
  83 #define JLINK_MAX_SPEED 12000
  84
  85 /* External interface functions */
  86 static int jlink_execute_queue(void);
  87 static int jlink_speed(int speed);
  88 static int jlink_speed_div(int speed, int* khz);
  89 static int jlink_khz(int khz, int *jtag_speed);
  90 static int jlink_register_commands(struct command_context_s *cmd_ctx);
  91 static int jlink_init(void);
  92 static int jlink_quit(void);
  93
  94 /* CLI command handler functions */
  95 static int jlink_handle_jlink_info_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
  96 static int jlink_handle_jlink_hw_jtag_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
  97
  98 /* Queue command functions */
  99 static void jlink_end_state(tap_state_t state);
 100 static void jlink_state_move(void);
 101 static void jlink_path_move(int num_states, tap_state_t *path);
 102 static void jlink_runtest(int num_cycles);
 103 static void jlink_scan(bool ir_scan, enum scan_type type, u8 *buffer, int scan_size, scan_command_t *command);
 104 static void jlink_reset(int trst, int srst);
 105 static void jlink_simple_command(u8 command);
 106 static int jlink_get_status(void);
 107
 108 /* J-Link tap buffer functions */
 109 static void jlink_tap_init(void);
 110 static int jlink_tap_execute(void);
 111 static void jlink_tap_ensure_space(int scans, int bits);
 112 static void jlink_tap_append_step(int tms, int tdi);
 113 static void jlink_tap_append_scan(int length, u8 *buffer, scan_command_t *command);
 114
 115 /* Jlink lowlevel functions */
 116 typedef struct jlink_jtag
 117 {
 118         struct usb_dev_handle* usb_handle;
 119 } jlink_jtag_t;
 120
 121 static jlink_jtag_t *jlink_usb_open(void);
 122 static void jlink_usb_close(jlink_jtag_t *jlink_jtag);
 123 static int jlink_usb_message(jlink_jtag_t *jlink_jtag, int out_length, int in_length);
 124 static int jlink_usb_write(jlink_jtag_t *jlink_jtag, int out_length);
 125 static int jlink_usb_read(jlink_jtag_t *jlink_jtag, int expected_size);
 126 static int jlink_usb_read_emu_result(jlink_jtag_t *jlink_jtag);
 127
 128 /* helper functions */
 129 static int jlink_get_version_info(void);
 130
 131 #ifdef _DEBUG_USB_COMMS_
 132 static void jlink_debug_buffer(u8 *buffer, int length);
 133 #endif
 134
 135 static enum tap_state jlink_last_state = TAP_RESET;
 136
 137 static jlink_jtag_t* jlink_jtag_handle;
 138
 139 /***************************************************************************/
 140 /* External interface implementation */
 141
 142 jtag_interface_t jlink_interface =
 143 {
 144         .name = "jlink",
 145         .execute_queue = jlink_execute_queue,
 146         .speed = jlink_speed,
 147         .speed_div = jlink_speed_div,
 148         .khz = jlink_khz,
 149         .register_commands = jlink_register_commands,
 150         .init = jlink_init,
 151         .quit = jlink_quit
 152 };
 153
 154 static void jlink_execute_runtest(jtag_command_t *cmd)
 155 {
 156         DEBUG_JTAG_IO("runtest %i cycles, end in %i",
 157                         cmd->cmd.runtest->num_cycles,
 158                         cmd->cmd.runtest->end_state);
 159
 160         jlink_end_state(cmd->cmd.runtest->end_state);
 161
 162         jlink_runtest(cmd->cmd.runtest->num_cycles);
 163 }
 164
 165 static void jlink_execute_statemove(jtag_command_t *cmd)
 166 {
 167         DEBUG_JTAG_IO("statemove end in %i", cmd->cmd.statemove->end_state);
 168
 169         jlink_end_state(cmd->cmd.statemove->end_state);
 170         jlink_state_move();
 171 }
 172
 173 static void jlink_execute_pathmove(jtag_command_t *cmd)
 174 {
 175         DEBUG_JTAG_IO("pathmove: %i states, end in %i",
 176                 cmd->cmd.pathmove->num_states,
 177                 cmd->cmd.pathmove->path[cmd->cmd.pathmove->num_states - 1]);
 178
 179         jlink_path_move(cmd->cmd.pathmove->num_states,
 180                         cmd->cmd.pathmove->path);
 181 }
 182
 183 static void jlink_execute_scan(jtag_command_t *cmd)
 184 {
 185         int scan_size;
 186         enum scan_type type;
 187         u8 *buffer;
 188
 189         DEBUG_JTAG_IO("scan end in %s", tap_state_name(cmd->cmd.scan->end_state));
 190
 191         jlink_end_state(cmd->cmd.scan->end_state);
 192
 193         scan_size = jtag_build_buffer(cmd->cmd.scan, &buffer);
 194         DEBUG_JTAG_IO("scan input, length = %d", scan_size);
 195
 196 #ifdef _DEBUG_USB_COMMS_
 197         jlink_debug_buffer(buffer, (scan_size + 7) / 8);
 198 #endif
 199         type = jtag_scan_type(cmd->cmd.scan);
 200         jlink_scan(cmd->cmd.scan->ir_scan,
 201                         type, buffer, scan_size, cmd->cmd.scan);
 202 }
 203
 204 static void jlink_execute_reset(jtag_command_t *cmd)
 205 {
 206         DEBUG_JTAG_IO("reset trst: %i srst %i",
 207                         cmd->cmd.reset->trst, cmd->cmd.reset->srst);
 208
 209         jlink_tap_execute();
 210         jlink_reset(cmd->cmd.reset->trst, cmd->cmd.reset->srst);
 211         jlink_tap_execute();
 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_RUNTEST:   jlink_execute_runtest(cmd); break;
 226         case JTAG_STATEMOVE: jlink_execute_statemove(cmd); break;
 227         case JTAG_PATHMOVE:  jlink_execute_pathmove(cmd); break;
 228         case JTAG_SCAN:      jlink_execute_scan(cmd); break;
 229         case JTAG_RESET:     jlink_execute_reset(cmd); break;
 230         case JTAG_SLEEP:     jlink_execute_sleep(cmd); break;
 231         default:
 232                 LOG_ERROR("BUG: unknown JTAG command type encountered");
 233                 exit(-1);
 234         }
 235 }
 236
 237 static int jlink_execute_queue(void)
 238 {
 239         jtag_command_t *cmd = jtag_command_queue;
 240
 241         while (cmd != NULL)
 242         {
 243                 jlink_execute_command(cmd);
 244                 cmd = cmd->next;
 245         }
 246
 247         return jlink_tap_execute();
 248 }
 249
 250 /* Sets speed in kHz. */
 251 static int jlink_speed(int speed)
 252 {
 253         int result;
 254
 255         if (speed > JLINK_MAX_SPEED)
 256         {
 257                 LOG_INFO("Ignoring speed request: %dkHz exceeds %dkHz maximum",
 258                                 speed, JLINK_MAX_SPEED);
 259                 return ERROR_OK;
 260         }
 261
 262         /* check for RTCK setting */
 263         if (speed == 0)
 264                 speed = -1;
 265
 266         usb_out_buffer[0] = EMU_CMD_SET_SPEED;
 267         usb_out_buffer[1] = (speed >> 0) & 0xff;
 268         usb_out_buffer[2] = (speed >> 8) & 0xff;
 269
 270         result = jlink_usb_write(jlink_jtag_handle, 3);
 271         if (result != 3)
 272         {
 273                 LOG_ERROR("J-Link setting speed failed (%d)", result);
 274                 return ERROR_JTAG_DEVICE_ERROR;
 275         }
 276
 277         return ERROR_OK;
 278 }
 279
 280 static int jlink_speed_div(int speed, int* khz)
 281 {
 282         *khz = speed;
 283
 284         return ERROR_OK;
 285 }
 286
 287 static int jlink_khz(int khz, int *jtag_speed)
 288 {
 289         *jtag_speed = khz;
 290
 291         return ERROR_OK;
 292 }
 293
 294 static int jlink_register_commands(struct command_context_s *cmd_ctx)
 295 {
 296
 297         register_command(cmd_ctx, NULL, "jlink_info",
 298                 &jlink_handle_jlink_info_command, COMMAND_EXEC,
 299                 "query jlink info");
 300         register_command(cmd_ctx, NULL, "jlink_hw_jtag",
 301                 &jlink_handle_jlink_hw_jtag_command, COMMAND_EXEC,
 302                 "set/get jlink hw jtag command version [2|3]");
 303         return ERROR_OK;
 304 }
 305
 306 static int jlink_init(void)
 307 {
 308         int check_cnt;
 309
 310         jlink_jtag_handle = jlink_usb_open();
 311
 312         if (jlink_jtag_handle == 0)
 313         {
 314                 LOG_ERROR("Cannot find jlink Interface! Please check connection and permissions.");
 315                 return ERROR_JTAG_INIT_FAILED;
 316         }
 317
 318         jlink_hw_jtag_version = 2;
 319         check_cnt = 0;
 320         while (check_cnt < 3)
 321         {
 322                 if (jlink_get_version_info() == ERROR_OK)
 323                 {
 324                         /* attempt to get status */
 325                         jlink_get_status();
 326                         break;
 327                 }
 328
 329                 check_cnt++;
 330         }
 331
 332         if (check_cnt == 3)
 333         {
 334                 LOG_INFO("J-Link initial read failed, don't worry");
 335         }
 336
 337         LOG_INFO("J-Link JTAG Interface ready");
 338
 339         jlink_reset(0, 0);
 340         jtag_sleep(3000);
 341         jlink_tap_init();
 342         jlink_speed(jtag_speed);
 343
 344         return ERROR_OK;
 345 }
 346
 347 static int jlink_quit(void)
 348 {
 349         jlink_usb_close(jlink_jtag_handle);
 350         return ERROR_OK;
 351 }
 352
 353 /***************************************************************************/
 354 /* Queue command implementations */
 355
 356 static void jlink_end_state(tap_state_t state)
 357 {
 358         if (tap_is_state_stable(state))
 359         {
 360                 tap_set_end_state(state);
 361         }
 362         else
 363         {
 364                 LOG_ERROR("BUG: %i is not a valid end state", state);
 365                 exit(-1);
 366         }
 367 }
 368
 369 /* Goes to the end state. */
 370 static void jlink_state_move(void)
 371 {
 372         int i;
 373         int tms = 0;
 374         u8 tms_scan = tap_get_tms_path(tap_get_state(), tap_get_end_state());
 375         u8 tms_scan_bits = tap_get_tms_path_len(tap_get_state(), tap_get_end_state());
 376
 377         for (i = 0; i < tms_scan_bits; i++)
 378         {
 379                 tms = (tms_scan >> i) & 1;
 380                 jlink_tap_append_step(tms, 0);
 381         }
 382
 383         tap_set_state(tap_get_end_state());
 384 }
 385
 386 static void jlink_path_move(int num_states, tap_state_t *path)
 387 {
 388         int i;
 389
 390         for (i = 0; i < num_states; i++)
 391         {
 392                 if (path[i] == tap_state_transition(tap_get_state(), false))
 393                 {
 394                         jlink_tap_append_step(0, 0);
 395                 }
 396                 else if (path[i] == tap_state_transition(tap_get_state(), true))
 397                 {
 398                         jlink_tap_append_step(1, 0);
 399                 }
 400                 else
 401                 {
 402                         LOG_ERROR("BUG: %s -> %s isn't a valid TAP transition", tap_state_name(tap_get_state()), tap_state_name(path[i]));
 403                         exit(-1);
 404                 }
 405
 406                 tap_set_state(path[i]);
 407         }
 408
 409         tap_set_end_state(tap_get_state());
 410 }
 411
 412 static void jlink_runtest(int num_cycles)
 413 {
 414         int i;
 415
 416         tap_state_t saved_end_state = tap_get_end_state();
 417
 418         jlink_tap_ensure_space(1,num_cycles + 16);
 419
 420         /* only do a state_move when we're not already in IDLE */
 421         if (tap_get_state() != TAP_IDLE)
 422         {
 423                 jlink_end_state(TAP_IDLE);
 424                 jlink_state_move();
 425 //              num_cycles--;
 426         }
 427
 428         /* execute num_cycles */
 429         for (i = 0; i < num_cycles; i++)
 430         {
 431                 jlink_tap_append_step(0, 0);
 432         }
 433
 434         /* finish in end_state */
 435         jlink_end_state(saved_end_state);
 436         if (tap_get_state() != tap_get_end_state())
 437         {
 438                 jlink_state_move();
 439         }
 440 }
 441
 442 static void jlink_scan(bool ir_scan, enum scan_type type, u8 *buffer, int scan_size, scan_command_t *command)
 443 {
 444         tap_state_t saved_end_state;
 445
 446         jlink_tap_ensure_space(1, scan_size + 16);
 447
 448         saved_end_state = tap_get_end_state();
 449
 450         /* Move to appropriate scan state */
 451         jlink_end_state(ir_scan ? TAP_IRSHIFT : TAP_DRSHIFT);
 452
 453         /* Only move if we're not already there */
 454         if (tap_get_state() != tap_get_end_state())
 455                 jlink_state_move();
 456
 457         jlink_end_state(saved_end_state);
 458
 459         /* Scan */
 460         jlink_tap_append_scan(scan_size, buffer, command);
 461
 462         /* We are in Exit1, go to Pause */
 463         jlink_tap_append_step(0, 0);
 464
 465         tap_set_state(ir_scan ? TAP_IRPAUSE : TAP_DRPAUSE);
 466
 467         if (tap_get_state() != tap_get_end_state())
 468         {
 469                 jlink_state_move();
 470         }
 471 }
 472
 473 static void jlink_reset(int trst, int srst)
 474 {
 475         LOG_DEBUG("trst: %i, srst: %i", trst, srst);
 476
 477         /* Signals are active low */
 478         if (srst == 0)
 479         {
 480                 jlink_simple_command(EMU_CMD_HW_RESET1);
 481         }
 482         if (srst == 1)
 483         {
 484                 jlink_simple_command(EMU_CMD_HW_RESET0);
 485         }
 486
 487         if (trst == 1)
 488         {
 489                 jlink_simple_command(EMU_CMD_HW_TRST0);
 490         }
 491         if (trst == 0)
 492         {
 493                 jlink_simple_command(EMU_CMD_HW_TRST1);
 494                 jtag_sleep(5000);
 495                 jlink_end_state(TAP_RESET);
 496                 jlink_state_move();
 497         }
 498 }
 499
 500 static void jlink_simple_command(u8 command)
 501 {
 502         int result;
 503
 504         DEBUG_JTAG_IO("0x%02x", command);
 505
 506         usb_out_buffer[0] = command;
 507         result = jlink_usb_write(jlink_jtag_handle, 1);
 508
 509         if (result != 1)
 510         {
 511                 LOG_ERROR("J-Link command 0x%02x failed (%d)", command, result);
 512         }
 513 }
 514
 515 static int jlink_get_status(void)
 516 {
 517         int result;
 518
 519         jlink_simple_command(EMU_CMD_GET_STATE);
 520
 521         result = jlink_usb_read(jlink_jtag_handle, 8);
 522         if (result != 8)
 523         {
 524                 LOG_ERROR("J-Link command EMU_CMD_GET_STATE failed (%d)\n", result);
 525                 return ERROR_JTAG_DEVICE_ERROR;
 526         }
 527
 528         int vref = usb_in_buffer[0] + (usb_in_buffer[1] << 8);
 529         LOG_INFO("Vref = %d.%d TCK = %d TDI = %d TDO = %d TMS = %d SRST = %d TRST = %d\n", \
 530                 vref / 1000, vref % 1000, \
 531                 usb_in_buffer[2], usb_in_buffer[3], usb_in_buffer[4], \
 532                 usb_in_buffer[5], usb_in_buffer[6], usb_in_buffer[7]);
 533
 534         if (vref < 1500)
 535                 LOG_ERROR("Vref too low. Check Target Power\n");
 536
 537         return ERROR_OK;
 538 }
 539
 540 static int jlink_get_version_info(void)
 541 {
 542         int result;
 543         int len;
 544         u32 jlink_caps, jlink_max_size;
 545
 546         /* query hardware version */
 547         jlink_simple_command(EMU_CMD_VERSION);
 548
 549         result = jlink_usb_read(jlink_jtag_handle, 2);
 550         if (2 != result)
 551         {
 552                 LOG_ERROR("J-Link command EMU_CMD_VERSION failed (%d)\n", result);
 553                 return ERROR_JTAG_DEVICE_ERROR;
 554         }
 555
 556         len = buf_get_u32(usb_in_buffer, 0, 16);
 557         if (len > JLINK_IN_BUFFER_SIZE)
 558         {
 559                 LOG_ERROR("J-Link command EMU_CMD_VERSION impossible return length 0x%0x", len);
 560                 len = JLINK_IN_BUFFER_SIZE;
 561         }
 562
 563         result = jlink_usb_read(jlink_jtag_handle, len);
 564         if (result != len)
 565         {
 566                 LOG_ERROR("J-Link command EMU_CMD_VERSION failed (%d)\n", result);
 567                 return ERROR_JTAG_DEVICE_ERROR;
 568         }
 569
 570         usb_in_buffer[result] = 0;
 571         LOG_INFO("%s", (char *)usb_in_buffer);
 572
 573         /* query hardware capabilities */
 574         jlink_simple_command(EMU_CMD_GET_CAPS);
 575
 576         result = jlink_usb_read(jlink_jtag_handle, 4);
 577         if (4 != result)
 578         {
 579                 LOG_ERROR("J-Link command EMU_CMD_GET_CAPS failed (%d)\n", result);
 580                 return ERROR_JTAG_DEVICE_ERROR;
 581         }
 582
 583         jlink_caps = buf_get_u32(usb_in_buffer, 0, 32);
 584         LOG_INFO("JLink caps 0x%x", jlink_caps);
 585
 586         if (jlink_caps & (1 << EMU_CAP_GET_HW_VERSION))
 587         {
 588                 /* query hardware version */
 589                 jlink_simple_command(EMU_CMD_GET_HW_VERSION);
 590
 591                 result = jlink_usb_read(jlink_jtag_handle, 4);
 592                 if (4 != result)
 593                 {
 594                         LOG_ERROR("J-Link command EMU_CMD_GET_HW_VERSION failed (%d)\n", result);
 595                         return ERROR_JTAG_DEVICE_ERROR;
 596                 }
 597
 598                 u32 jlink_hw_version = buf_get_u32(usb_in_buffer, 0, 32);
 599                 u32 major_revision = (jlink_hw_version / 10000) % 100;
 600                 if (major_revision >= 5)
 601                         jlink_hw_jtag_version = 3;
 602
 603                 LOG_INFO("JLink hw version %i", jlink_hw_version);
 604         }
 605
 606         if (jlink_caps & (1 << EMU_CAP_GET_MAX_BLOCK_SIZE))
 607         {
 608                 /* query hardware maximum memory block */
 609                 jlink_simple_command(EMU_CMD_GET_MAX_MEM_BLOCK);
 610
 611                 result = jlink_usb_read(jlink_jtag_handle, 4);
 612                 if (4 != result)
 613                 {
 614                         LOG_ERROR("J-Link command EMU_CMD_GET_MAX_MEM_BLOCK failed (%d)\n", result);
 615                         return ERROR_JTAG_DEVICE_ERROR;
 616                 }
 617
 618                 jlink_max_size = buf_get_u32(usb_in_buffer, 0, 32);
 619                 LOG_INFO("JLink max mem block %i", jlink_max_size);
 620         }
 621
 622         return ERROR_OK;
 623 }
 624
 625 static int jlink_handle_jlink_info_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 626 {
 627         if (jlink_get_version_info() == ERROR_OK)
 628         {
 629                 /* attempt to get status */
 630                 jlink_get_status();
 631         }
 632
 633         return ERROR_OK;
 634 }
 635
 636 static int jlink_handle_jlink_hw_jtag_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 637 {
 638         switch (argc) {
 639         case 0:
 640                 command_print(cmd_ctx, "jlink hw jtag  %i", jlink_hw_jtag_version);
 641                 break;
 642         case 1: {
 643                 int request_version = atoi(args[0]);
 644                 switch (request_version) {
 645                 case 2: case 3:
 646                         jlink_hw_jtag_version = request_version;
 647                         break;
 648                 default:
 649                         return ERROR_COMMAND_SYNTAX_ERROR;
 650                 }
 651                 break;
 652         }
 653         default:
 654                 return ERROR_COMMAND_SYNTAX_ERROR;
 655         }
 656
 657         return ERROR_OK;
 658 }
 659
 660 /***************************************************************************/
 661 /* J-Link tap functions */
 662
 663
 664 static unsigned tap_length=0;
 665 static u8 tms_buffer[JLINK_TAP_BUFFER_SIZE];
 666 static u8 tdi_buffer[JLINK_TAP_BUFFER_SIZE];
 667 static u8 tdo_buffer[JLINK_TAP_BUFFER_SIZE];
 668
 669 typedef struct
 670 {
 671         int first;      /* First bit position in tdo_buffer to read */
 672         int length; /* Number of bits to read */
 673         scan_command_t *command; /* Corresponding scan command */
 674         u8 *buffer;
 675 } pending_scan_result_t;
 676
 677 #define MAX_PENDING_SCAN_RESULTS 256
 678
 679 static int pending_scan_results_length;
 680 static pending_scan_result_t pending_scan_results_buffer[MAX_PENDING_SCAN_RESULTS];
 681
 682 static void jlink_tap_init(void)
 683 {
 684         tap_length = 0;
 685         pending_scan_results_length = 0;
 686 }
 687
 688 static void jlink_tap_ensure_space(int scans, int bits)
 689 {
 690         int available_scans = MAX_PENDING_SCAN_RESULTS - pending_scan_results_length;
 691         int available_bits = JLINK_TAP_BUFFER_SIZE * 8 - tap_length - 32;
 692
 693         if (scans > available_scans || bits > available_bits)
 694         {
 695                 jlink_tap_execute();
 696         }
 697 }
 698
 699 static void jlink_tap_append_step(int tms, int tdi)
 700 {
 701         int index = tap_length / 8;
 702
 703         if (index >= JLINK_TAP_BUFFER_SIZE)
 704         {
 705                 LOG_ERROR("jlink_tap_append_step: overflow");
 706                 *(u32 *)0xFFFFFFFF = 0;
 707                 exit(-1);
 708         }
 709
 710         int bit_index = tap_length % 8;
 711         u8 bit = 1 << bit_index;
 712
 713         // we do not pad TMS, so be sure to initialize all bits
 714         if (0 == bit_index)
 715         {
 716                 tms_buffer[index] = tdi_buffer[index] = 0;
 717         }
 718
 719         if (tms)
 720                 tms_buffer[index] |= bit;
 721         else
 722                 tms_buffer[index] &= ~bit;
 723
 724         if (tdi)
 725                 tdi_buffer[index] |= bit;
 726         else
 727                 tdi_buffer[index] &= ~bit;
 728
 729         tap_length++;
 730 }
 731
 732 static void jlink_tap_append_scan(int length, u8 *buffer, scan_command_t *command)
 733 {
 734         pending_scan_result_t *pending_scan_result =
 735                 &pending_scan_results_buffer[pending_scan_results_length];
 736         int i;
 737
 738         pending_scan_result->first = tap_length;
 739         pending_scan_result->length = length;
 740         pending_scan_result->command = command;
 741         pending_scan_result->buffer = buffer;
 742
 743         for (i = 0; i < length; i++)
 744         {
 745                 int tms = (i < (length - 1)) ? 0 : 1;
 746                 int tdi = (buffer[i / 8] & (1 << (i % 8)))!=0;
 747                 jlink_tap_append_step(tms, tdi);
 748         }
 749         pending_scan_results_length++;
 750 }
 751
 752 /* Pad and send a tap sequence to the device, and receive the answer.
 753  * For the purpose of padding we assume that we are in idle or pause state. */
 754 static int jlink_tap_execute(void)
 755 {
 756         int byte_length;
 757         int i;
 758         int result;
 759
 760         if (!tap_length)
 761                 return ERROR_OK;
 762
 763         /* JLink returns an extra NULL in packet when size of in message is a multiple of 64, creates problems with usb comms */
 764         /* WARNING This will interfere with tap state counting */
 765         while ((TAP_SCAN_BYTES(tap_length)%64)==0)
 766         {
 767                 jlink_tap_append_step((tap_get_state() == TAP_RESET)?1:0, 0);
 768         }
 769
 770         // number of full bytes (plus one if some would be left over)
 771         byte_length = TAP_SCAN_BYTES(tap_length);
 772
 773         bool use_jtag3 = jlink_hw_jtag_version >= 3;
 774         usb_out_buffer[0] = use_jtag3 ? EMU_CMD_HW_JTAG3 : EMU_CMD_HW_JTAG2;
 775         usb_out_buffer[1] = 0;
 776         usb_out_buffer[2] = (tap_length >> 0) & 0xff;
 777         usb_out_buffer[3] = (tap_length >> 8) & 0xff;
 778         memcpy(usb_out_buffer + 4, tms_buffer, byte_length);
 779         memcpy(usb_out_buffer + 4 + byte_length, tdi_buffer, byte_length);
 780
 781         jlink_last_state = jtag_debug_state_machine(tms_buffer, tdi_buffer,
 782                         tap_length, jlink_last_state);
 783
 784         result = jlink_usb_message(jlink_jtag_handle, 4 + 2 * byte_length, byte_length);
 785         if (result != byte_length)
 786         {
 787                 LOG_ERROR("jlink_tap_execute, wrong result %d (expected %d)", result, byte_length);
 788                 jlink_tap_init();
 789                 return ERROR_JTAG_QUEUE_FAILED;
 790         }
 791
 792         memcpy(tdo_buffer, usb_in_buffer, byte_length);
 793
 794         for (i = 0; i < pending_scan_results_length; i++)
 795         {
 796                 pending_scan_result_t *pending_scan_result = &pending_scan_results_buffer[i];
 797                 u8 *buffer = pending_scan_result->buffer;
 798                 int length = pending_scan_result->length;
 799                 int first = pending_scan_result->first;
 800                 scan_command_t *command = pending_scan_result->command;
 801
 802                 /* Copy to buffer */
 803                 buf_set_buf(tdo_buffer, first, buffer, 0, length);
 804
 805                 DEBUG_JTAG_IO("pending scan result, length = %d", length);
 806
 807 #ifdef _DEBUG_USB_COMMS_
 808                 jlink_debug_buffer(buffer, TAP_SCAN_BYTES(length));
 809 #endif
 810
 811                 if (jtag_read_buffer(buffer, command) != ERROR_OK)
 812                 {
 813                         jlink_tap_init();
 814                         return ERROR_JTAG_QUEUE_FAILED;
 815                 }
 816
 817                 if (pending_scan_result->buffer != NULL)
 818                 {
 819                         free(pending_scan_result->buffer);
 820                 }
 821         }
 822
 823         jlink_tap_init();
 824         return ERROR_OK;
 825 }
 826
 827 /*****************************************************************************/
 828 /* JLink USB low-level functions */
 829
 830 static jlink_jtag_t* jlink_usb_open()
 831 {
 832         struct usb_bus *busses;
 833         struct usb_bus *bus;
 834         struct usb_device *dev;
 835
 836         jlink_jtag_t *result;
 837
 838         result = (jlink_jtag_t*) malloc(sizeof(jlink_jtag_t));
 839
 840         usb_init();
 841         usb_find_busses();
 842         usb_find_devices();
 843
 844         busses = usb_get_busses();
 845
 846         /* find jlink_jtag device in usb bus */
 847
 848         for (bus = busses; bus; bus = bus->next)
 849         {
 850                 for (dev = bus->devices; dev; dev = dev->next)
 851                 {
 852                         if ((dev->descriptor.idVendor == VID) && (dev->descriptor.idProduct == PID))
 853                         {
 854                                 result->usb_handle = usb_open(dev);
 855
 856                                 /* usb_set_configuration required under win32 */
 857                                 usb_set_configuration(result->usb_handle, dev->config[0].bConfigurationValue);
 858                                 usb_claim_interface(result->usb_handle, 0);
 859
 860 #if 0
 861                                 /*
 862                                  * This makes problems under Mac OS X. And is not needed
 863                                  * under Windows. Hopefully this will not break a linux build
 864                                  */
 865                                 usb_set_altinterface(result->usb_handle, 0);
 866 #endif
 867                                 struct usb_interface *iface = dev->config->interface;
 868                                 struct usb_interface_descriptor *desc = iface->altsetting;
 869                                 for (int i = 0; i < desc->bNumEndpoints; i++)
 870                                 {
 871                                         u8 epnum = desc->endpoint[i].bEndpointAddress;
 872                                         bool is_input = epnum & 0x80;
 873                                         LOG_DEBUG("usb ep %s %02x", is_input ? "in" : "out", epnum);
 874                                         if (is_input)
 875                                                 jlink_read_ep = epnum;
 876                                         else
 877                                                 jlink_write_ep = epnum;
 878                                 }
 879
 880                                 return result;
 881                         }
 882                 }
 883         }
 884
 885         free(result);
 886         return NULL;
 887 }
 888
 889 static void jlink_usb_close(jlink_jtag_t *jlink_jtag)
 890 {
 891         usb_close(jlink_jtag->usb_handle);
 892         free(jlink_jtag);
 893 }
 894
 895 /* Send a message and receive the reply. */
 896 static int jlink_usb_message(jlink_jtag_t *jlink_jtag, int out_length, int in_length)
 897 {
 898         int result;
 899
 900         result = jlink_usb_write(jlink_jtag, out_length);
 901         if (result != out_length)
 902         {
 903                 LOG_ERROR("usb_bulk_write failed (requested=%d, result=%d)",
 904                                 out_length, result);
 905                 return ERROR_JTAG_DEVICE_ERROR;
 906         }
 907
 908         result = jlink_usb_read(jlink_jtag, in_length);
 909         if ((result != in_length) && (result != (in_length + 1)))
 910         {
 911                 LOG_ERROR("usb_bulk_read failed (requested=%d, result=%d)",
 912                                 in_length, result);
 913                 return ERROR_JTAG_DEVICE_ERROR;
 914         }
 915
 916         if (jlink_hw_jtag_version < 3)
 917                 return result;
 918
 919         int result2 = ERROR_OK;
 920         if (result == in_length)
 921         {
 922                 /* Must read the result from the EMU too */
 923                 result2 = jlink_usb_read_emu_result(jlink_jtag);
 924                 if (1 != result2)
 925                 {
 926                         LOG_ERROR("jlink_usb_read_emu_result retried requested=1, result=%d, in_length=%i", result2,in_length);
 927                         /* Try again once, should only happen if (in_length%64==0) */
 928                         result2 = jlink_usb_read_emu_result(jlink_jtag);
 929                         if (1 != result2)
 930                         {
 931                                 LOG_ERROR("jlink_usb_read_emu_result failed "
 932                                         "(requested=1, result=%d)", result2);
 933                                 return ERROR_JTAG_DEVICE_ERROR;
 934                         }
 935                 }
 936
 937                 /* Check the result itself */
 938                 result2 = usb_emu_result_buffer[0];
 939         }
 940         else
 941         {
 942                 /* Save the result, then remove it from return value */
 943                 result2 = usb_in_buffer[result--];
 944         }
 945
 946         if (result2)
 947         {
 948                 LOG_ERROR("jlink_usb_message failed with result=%d)", result2);
 949                 return ERROR_JTAG_DEVICE_ERROR;
 950         }
 951
 952         return result;
 953 }
 954
 955 /* calls the given usb_bulk_* function, allowing for the data to trickle in with some timeouts  */
 956 static int usb_bulk_with_retries(
 957                 int (*f)(usb_dev_handle *, int, char *, int, int),
 958                 usb_dev_handle *dev, int ep,
 959                 char *bytes, int size, int timeout)
 960 {
 961         int tries = 3, count = 0;
 962
 963         while (tries && (count < size))
 964         {
 965                 int result = f(dev, ep, bytes + count, size - count, timeout);
 966                 if (result > 0)
 967                         count += result;
 968                 else if ((-ETIMEDOUT != result) || !--tries)
 969                         return result;
 970         }
 971         return count;
 972 }
 973
 974 static int wrap_usb_bulk_write(usb_dev_handle *dev, int ep,
 975                                char *buff, int size, int timeout)
 976 {
 977         /* usb_bulk_write() takes const char *buff */
 978         return usb_bulk_write(dev, ep, buff, size, timeout);
 979 }
 980
 981 static inline int usb_bulk_write_ex(usb_dev_handle *dev, int ep,
 982                 char *bytes, int size, int timeout)
 983 {
 984         return usb_bulk_with_retries(&wrap_usb_bulk_write,
 985                         dev, ep, bytes, size, timeout);
 986 }
 987
 988 static inline int usb_bulk_read_ex(usb_dev_handle *dev, int ep,
 989                 char *bytes, int size, int timeout)
 990 {
 991         return usb_bulk_with_retries(&usb_bulk_read,
 992                         dev, ep, bytes, size, timeout);
 993 }
 994
 995 /* Write data from out_buffer to USB. */
 996 static int jlink_usb_write(jlink_jtag_t *jlink_jtag, int out_length)
 997 {
 998         int result;
 999
1000         if (out_length > JLINK_OUT_BUFFER_SIZE)
1001         {
1002                 LOG_ERROR("jlink_jtag_write illegal out_length=%d (max=%d)", out_length, JLINK_OUT_BUFFER_SIZE);
1003                 return -1;
1004         }
1005
1006         result = usb_bulk_write_ex(jlink_jtag->usb_handle, jlink_write_ep,
1007                 (char *)usb_out_buffer, out_length, JLINK_USB_TIMEOUT);
1008
1009         DEBUG_JTAG_IO("jlink_usb_write, out_length = %d, result = %d", out_length, result);
1010
1011 #ifdef _DEBUG_USB_COMMS_
1012         jlink_debug_buffer(usb_out_buffer, out_length);
1013 #endif
1014         return result;
1015 }
1016
1017 /* Read data from USB into in_buffer. */
1018 static int jlink_usb_read(jlink_jtag_t *jlink_jtag, int expected_size)
1019 {
1020         int result = usb_bulk_read_ex(jlink_jtag->usb_handle, jlink_read_ep,
1021                 (char *)usb_in_buffer, expected_size, JLINK_USB_TIMEOUT);
1022
1023         DEBUG_JTAG_IO("jlink_usb_read, result = %d", result);
1024
1025 #ifdef _DEBUG_USB_COMMS_
1026         jlink_debug_buffer(usb_in_buffer, result);
1027 #endif
1028         return result;
1029 }
1030
1031 /* Read the result from the previous EMU cmd into result_buffer. */
1032 static int jlink_usb_read_emu_result(jlink_jtag_t *jlink_jtag)
1033 {
1034         int result = usb_bulk_read_ex(jlink_jtag->usb_handle, jlink_read_ep,
1035                 (char *)usb_emu_result_buffer, 1 /* JLINK_EMU_RESULT_BUFFER_SIZE */,
1036                 JLINK_USB_TIMEOUT);
1037
1038         DEBUG_JTAG_IO("jlink_usb_read_result, result = %d", result);
1039
1040 #ifdef _DEBUG_USB_COMMS_
1041         jlink_debug_buffer(usb_emu_result_buffer, result);
1042 #endif
1043         return result;
1044 }
1045
1046 #ifdef _DEBUG_USB_COMMS_
1047 #define BYTES_PER_LINE  16
1048
1049 static void jlink_debug_buffer(u8 *buffer, int length)
1050 {
1051         char line[81];
1052         char s[4];
1053         int i;
1054         int j;
1055
1056         for (i = 0; i < length; i += BYTES_PER_LINE)
1057         {
1058                 snprintf(line, 5, "%04x", i);
1059                 for (j = i; j < i + BYTES_PER_LINE && j < length; j++)
1060                 {
1061                         snprintf(s, 4, " %02x", buffer[j]);
1062                         strcat(line, s);
1063                 }
1064                 LOG_DEBUG("%s", line);
1065         }
1066 }
1067 #endif
1068