src/jtag/drivers/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 <jtag/interface.h>
  29 #include <jtag/commands.h>
  30 #include "usb_common.h"
  31
  32
  33 #define VID 0x1366
  34 #define PID 0x0101
  35
  36 #define JLINK_WRITE_ENDPOINT    0x02
  37 #define JLINK_READ_ENDPOINT             0x81
  38
  39 static unsigned int jlink_write_ep = JLINK_WRITE_ENDPOINT;
  40 static unsigned int jlink_read_ep = JLINK_READ_ENDPOINT;
  41 static unsigned int jlink_hw_jtag_version = 2;
  42
  43 #define JLINK_USB_TIMEOUT               1000
  44
  45 // See Section 1.3.2 of the Segger JLink USB protocol manual
  46 /* 2048 is the max value we can use here */
  47 //#define JLINK_TAP_BUFFER_SIZE 2048
  48 #define JLINK_TAP_BUFFER_SIZE 256
  49 //#define JLINK_TAP_BUFFER_SIZE 384
  50
  51 #define JLINK_IN_BUFFER_SIZE                    2048
  52 #define JLINK_OUT_BUFFER_SIZE                   2*2048 + 4
  53 #define JLINK_EMU_RESULT_BUFFER_SIZE    64
  54
  55 /* Global USB buffers */
  56 static uint8_t usb_in_buffer[JLINK_IN_BUFFER_SIZE];
  57 static uint8_t usb_out_buffer[JLINK_OUT_BUFFER_SIZE];
  58 static uint8_t usb_emu_result_buffer[JLINK_EMU_RESULT_BUFFER_SIZE];
  59
  60 /* Constants for JLink command */
  61 #define EMU_CMD_VERSION         0x01
  62 #define EMU_CMD_SET_SPEED               0x05
  63 #define EMU_CMD_GET_STATE               0x07
  64 #define EMU_CMD_HW_CLOCK                        0xc8
  65 #define EMU_CMD_HW_TMS0                 0xc9
  66 #define EMU_CMD_HW_TMS1                 0xca
  67 #define EMU_CMD_HW_JTAG2                0xce
  68 #define EMU_CMD_HW_JTAG3                0xcf
  69 #define EMU_CMD_GET_MAX_MEM_BLOCK       0xd4
  70 #define EMU_CMD_HW_RESET0               0xdc
  71 #define EMU_CMD_HW_RESET1               0xdd
  72 #define EMU_CMD_HW_TRST0                0xde
  73 #define EMU_CMD_HW_TRST1                0xdf
  74 #define EMU_CMD_GET_CAPS                0xe8
  75 #define EMU_CMD_GET_HW_VERSION  0xf0
  76
  77 /* bits return from EMU_CMD_GET_CAPS */
  78 #define EMU_CAP_GET_HW_VERSION          1
  79 #define EMU_CAP_GET_MAX_BLOCK_SIZE      11
  80
  81 /* max speed 12MHz v5.0 jlink */
  82 #define JLINK_MAX_SPEED 12000
  83
  84 /* Queue command functions */
  85 static void jlink_end_state(tap_state_t state);
  86 static void jlink_state_move(void);
  87 static void jlink_path_move(int num_states, tap_state_t *path);
  88 static void jlink_runtest(int num_cycles);
  89 static void jlink_scan(bool ir_scan, enum scan_type type, uint8_t *buffer, int scan_size, struct scan_command *command);
  90 static void jlink_reset(int trst, int srst);
  91 static void jlink_simple_command(uint8_t command);
  92 static int jlink_get_status(void);
  93
  94 /* J-Link tap buffer functions */
  95 static void jlink_tap_init(void);
  96 static int jlink_tap_execute(void);
  97 static void jlink_tap_ensure_space(int scans, int bits);
  98 static void jlink_tap_append_step(int tms, int tdi);
  99 static void jlink_tap_append_scan(int length, uint8_t *buffer, struct scan_command *command);
 100
 101 /* Jlink lowlevel functions */
 102 struct jlink {
 103         struct usb_dev_handle* usb_handle;
 104 };
 105
 106 static struct jlink *jlink_usb_open(void);
 107 static void jlink_usb_close(struct jlink *jlink);
 108 static int jlink_usb_message(struct jlink *jlink, int out_length, int in_length);
 109 static int jlink_usb_write(struct jlink *jlink, int out_length);
 110 static int jlink_usb_read(struct jlink *jlink, int expected_size);
 111 static int jlink_usb_read_emu_result(struct jlink *jlink);
 112
 113 /* helper functions */
 114 static int jlink_get_version_info(void);
 115
 116 #ifdef _DEBUG_USB_COMMS_
 117 static void jlink_debug_buffer(uint8_t *buffer, int length);
 118 #endif
 119
 120 static enum tap_state jlink_last_state = TAP_RESET;
 121
 122 static struct jlink* jlink_handle;
 123
 124 /***************************************************************************/
 125 /* External interface implementation */
 126
 127 static void jlink_execute_runtest(struct jtag_command *cmd)
 128 {
 129         DEBUG_JTAG_IO("runtest %i cycles, end in %i",
 130                         cmd->cmd.runtest->num_cycles,
 131                         cmd->cmd.runtest->end_state);
 132
 133         jlink_end_state(cmd->cmd.runtest->end_state);
 134
 135         jlink_runtest(cmd->cmd.runtest->num_cycles);
 136 }
 137
 138 static void jlink_execute_statemove(struct jtag_command *cmd)
 139 {
 140         DEBUG_JTAG_IO("statemove end in %i", cmd->cmd.statemove->end_state);
 141
 142         jlink_end_state(cmd->cmd.statemove->end_state);
 143         jlink_state_move();
 144 }
 145
 146 static void jlink_execute_pathmove(struct jtag_command *cmd)
 147 {
 148         DEBUG_JTAG_IO("pathmove: %i states, end in %i",
 149                 cmd->cmd.pathmove->num_states,
 150                 cmd->cmd.pathmove->path[cmd->cmd.pathmove->num_states - 1]);
 151
 152         jlink_path_move(cmd->cmd.pathmove->num_states,
 153                         cmd->cmd.pathmove->path);
 154 }
 155
 156 static void jlink_execute_scan(struct jtag_command *cmd)
 157 {
 158         int scan_size;
 159         enum scan_type type;
 160         uint8_t *buffer;
 161
 162         DEBUG_JTAG_IO("scan end in %s", tap_state_name(cmd->cmd.scan->end_state));
 163
 164         jlink_end_state(cmd->cmd.scan->end_state);
 165
 166         scan_size = jtag_build_buffer(cmd->cmd.scan, &buffer);
 167         DEBUG_JTAG_IO("scan input, length = %d", scan_size);
 168
 169 #ifdef _DEBUG_USB_COMMS_
 170         jlink_debug_buffer(buffer, (scan_size + 7) / 8);
 171 #endif
 172         type = jtag_scan_type(cmd->cmd.scan);
 173         jlink_scan(cmd->cmd.scan->ir_scan,
 174                         type, buffer, scan_size, cmd->cmd.scan);
 175 }
 176
 177 static void jlink_execute_reset(struct jtag_command *cmd)
 178 {
 179         DEBUG_JTAG_IO("reset trst: %i srst %i",
 180                         cmd->cmd.reset->trst, cmd->cmd.reset->srst);
 181
 182         jlink_tap_execute();
 183         jlink_reset(cmd->cmd.reset->trst, cmd->cmd.reset->srst);
 184         jlink_tap_execute();
 185 }
 186
 187 static void jlink_execute_sleep(struct jtag_command *cmd)
 188 {
 189         DEBUG_JTAG_IO("sleep %" PRIi32 "", cmd->cmd.sleep->us);
 190         jlink_tap_execute();
 191         jtag_sleep(cmd->cmd.sleep->us);
 192 }
 193
 194 static void jlink_execute_command(struct jtag_command *cmd)
 195 {
 196         switch (cmd->type)
 197         {
 198         case JTAG_RUNTEST:   jlink_execute_runtest(cmd); break;
 199         case JTAG_STATEMOVE: jlink_execute_statemove(cmd); break;
 200         case JTAG_PATHMOVE:  jlink_execute_pathmove(cmd); break;
 201         case JTAG_SCAN:      jlink_execute_scan(cmd); break;
 202         case JTAG_RESET:     jlink_execute_reset(cmd); break;
 203         case JTAG_SLEEP:     jlink_execute_sleep(cmd); break;
 204         default:
 205                 LOG_ERROR("BUG: unknown JTAG command type encountered");
 206                 exit(-1);
 207         }
 208 }
 209
 210 static int jlink_execute_queue(void)
 211 {
 212         struct jtag_command *cmd = jtag_command_queue;
 213
 214         while (cmd != NULL)
 215         {
 216                 jlink_execute_command(cmd);
 217                 cmd = cmd->next;
 218         }
 219
 220         return jlink_tap_execute();
 221 }
 222
 223 /* Sets speed in kHz. */
 224 static int jlink_speed(int speed)
 225 {
 226         int result;
 227
 228         if (speed > JLINK_MAX_SPEED)
 229         {
 230                 LOG_INFO("Ignoring speed request: %dkHz exceeds %dkHz maximum",
 231                                 speed, JLINK_MAX_SPEED);
 232                 return ERROR_OK;
 233         }
 234
 235         /* check for RTCK setting */
 236         if (speed == 0)
 237                 speed = -1;
 238
 239         usb_out_buffer[0] = EMU_CMD_SET_SPEED;
 240         usb_out_buffer[1] = (speed >> 0) & 0xff;
 241         usb_out_buffer[2] = (speed >> 8) & 0xff;
 242
 243         result = jlink_usb_write(jlink_handle, 3);
 244         if (result != 3)
 245         {
 246                 LOG_ERROR("J-Link setting speed failed (%d)", result);
 247                 return ERROR_JTAG_DEVICE_ERROR;
 248         }
 249
 250         return ERROR_OK;
 251 }
 252
 253 static int jlink_speed_div(int speed, int* khz)
 254 {
 255         *khz = speed;
 256
 257         return ERROR_OK;
 258 }
 259
 260 static int jlink_khz(int khz, int *jtag_speed)
 261 {
 262         *jtag_speed = khz;
 263
 264         return ERROR_OK;
 265 }
 266
 267 static int jlink_init(void)
 268 {
 269         int i;
 270
 271         jlink_handle = jlink_usb_open();
 272
 273         if (jlink_handle == 0)
 274         {
 275                 LOG_ERROR("Cannot find jlink Interface! Please check connection and permissions.");
 276                 return ERROR_JTAG_INIT_FAILED;
 277         }
 278
 279         /*
 280          *  The next three instructions were added after discovering a problem while using an oscilloscope.  For the V8
 281          *      SAM-ICE dongle (and likely other j-link device variants), the reset line to the target microprocessor was found to
 282          *      cycle only intermittently during emulator startup (even after encountering the downstream reset instruction later
 283          *      in the code).  This was found to create two issues:  1) In general it is a bad practice to not reset a CPU to a known
 284          *      state when starting an emulator and 2) something critical happens inside the dongle when it does the first read
 285          *      following a new USB session.  Keeping the processor in reset during the first read collecting version information
 286          *      seems to prevent errant "J-Link command EMU_CMD_VERSION failed" issues.
 287          */
 288
 289         LOG_INFO("J-Link initialization started / target CPU reset initiated");
 290         jlink_simple_command(EMU_CMD_HW_TRST0);
 291         jlink_simple_command(EMU_CMD_HW_RESET0);
 292         usleep(1000);
 293
 294         jlink_hw_jtag_version = 2;
 295
 296         if (jlink_get_version_info() == ERROR_OK)
 297         {
 298                 /* attempt to get status */
 299                 jlink_get_status();
 300         }
 301
 302         LOG_INFO("J-Link JTAG Interface ready");
 303
 304         jlink_reset(0, 0);
 305         jtag_sleep(3000);
 306         jlink_tap_init();
 307         jlink_speed(jtag_get_speed());
 308
 309         /* v5/6 jlink seems to have an issue if the first tap move
 310          * is not divisible by 8, so we send a TLR on first power up */
 311         for (i = 0; i < 8; i++) {
 312                 jlink_tap_append_step(1, 0);
 313         }
 314         jlink_tap_execute();
 315
 316         return ERROR_OK;
 317 }
 318
 319 static int jlink_quit(void)
 320 {
 321         jlink_usb_close(jlink_handle);
 322         return ERROR_OK;
 323 }
 324
 325 /***************************************************************************/
 326 /* Queue command implementations */
 327
 328 static void jlink_end_state(tap_state_t state)
 329 {
 330         if (tap_is_state_stable(state))
 331         {
 332                 tap_set_end_state(state);
 333         }
 334         else
 335         {
 336                 LOG_ERROR("BUG: %i is not a valid end state", state);
 337                 exit(-1);
 338         }
 339 }
 340
 341 /* Goes to the end state. */
 342 static void jlink_state_move(void)
 343 {
 344         int i;
 345         int tms = 0;
 346         uint8_t tms_scan = tap_get_tms_path(tap_get_state(), tap_get_end_state());
 347         uint8_t tms_scan_bits = tap_get_tms_path_len(tap_get_state(), tap_get_end_state());
 348
 349         for (i = 0; i < tms_scan_bits; i++)
 350         {
 351                 tms = (tms_scan >> i) & 1;
 352                 jlink_tap_append_step(tms, 0);
 353         }
 354
 355         tap_set_state(tap_get_end_state());
 356 }
 357
 358 static void jlink_path_move(int num_states, tap_state_t *path)
 359 {
 360         int i;
 361
 362         for (i = 0; i < num_states; i++)
 363         {
 364                 if (path[i] == tap_state_transition(tap_get_state(), false))
 365                 {
 366                         jlink_tap_append_step(0, 0);
 367                 }
 368                 else if (path[i] == tap_state_transition(tap_get_state(), true))
 369                 {
 370                         jlink_tap_append_step(1, 0);
 371                 }
 372                 else
 373                 {
 374                         LOG_ERROR("BUG: %s -> %s isn't a valid TAP transition", tap_state_name(tap_get_state()), tap_state_name(path[i]));
 375                         exit(-1);
 376                 }
 377
 378                 tap_set_state(path[i]);
 379         }
 380
 381         tap_set_end_state(tap_get_state());
 382 }
 383
 384 static void jlink_runtest(int num_cycles)
 385 {
 386         int i;
 387
 388         tap_state_t saved_end_state = tap_get_end_state();
 389
 390         jlink_tap_ensure_space(1,num_cycles + 16);
 391
 392         /* only do a state_move when we're not already in IDLE */
 393         if (tap_get_state() != TAP_IDLE)
 394         {
 395                 jlink_end_state(TAP_IDLE);
 396                 jlink_state_move();
 397 //              num_cycles--;
 398         }
 399
 400         /* execute num_cycles */
 401         for (i = 0; i < num_cycles; i++)
 402         {
 403                 jlink_tap_append_step(0, 0);
 404         }
 405
 406         /* finish in end_state */
 407         jlink_end_state(saved_end_state);
 408         if (tap_get_state() != tap_get_end_state())
 409         {
 410                 jlink_state_move();
 411         }
 412 }
 413
 414 static void jlink_scan(bool ir_scan, enum scan_type type, uint8_t *buffer, int scan_size, struct scan_command *command)
 415 {
 416         tap_state_t saved_end_state;
 417
 418         jlink_tap_ensure_space(1, scan_size + 16);
 419
 420         saved_end_state = tap_get_end_state();
 421
 422         /* Move to appropriate scan state */
 423         jlink_end_state(ir_scan ? TAP_IRSHIFT : TAP_DRSHIFT);
 424
 425         /* Only move if we're not already there */
 426         if (tap_get_state() != tap_get_end_state())
 427                 jlink_state_move();
 428
 429         jlink_end_state(saved_end_state);
 430
 431         /* Scan */
 432         jlink_tap_append_scan(scan_size, buffer, command);
 433
 434         /* We are in Exit1, go to Pause */
 435         jlink_tap_append_step(0, 0);
 436
 437         tap_set_state(ir_scan ? TAP_IRPAUSE : TAP_DRPAUSE);
 438
 439         if (tap_get_state() != tap_get_end_state())
 440         {
 441                 jlink_state_move();
 442         }
 443 }
 444
 445 static void jlink_reset(int trst, int srst)
 446 {
 447         LOG_DEBUG("trst: %i, srst: %i", trst, srst);
 448
 449         /* Signals are active low */
 450         if (srst == 0)
 451         {
 452                 jlink_simple_command(EMU_CMD_HW_RESET1);
 453         }
 454         if (srst == 1)
 455         {
 456                 jlink_simple_command(EMU_CMD_HW_RESET0);
 457         }
 458
 459         if (trst == 1)
 460         {
 461                 jlink_simple_command(EMU_CMD_HW_TRST0);
 462         }
 463
 464         if (trst == 0)
 465         {
 466                 jlink_simple_command(EMU_CMD_HW_TRST1);
 467         }
 468 }
 469
 470 static void jlink_simple_command(uint8_t command)
 471 {
 472         int result;
 473
 474         DEBUG_JTAG_IO("0x%02x", command);
 475
 476         usb_out_buffer[0] = command;
 477         result = jlink_usb_write(jlink_handle, 1);
 478
 479         if (result != 1)
 480         {
 481                 LOG_ERROR("J-Link command 0x%02x failed (%d)", command, result);
 482         }
 483 }
 484
 485 static int jlink_get_status(void)
 486 {
 487         int result;
 488
 489         jlink_simple_command(EMU_CMD_GET_STATE);
 490
 491         result = jlink_usb_read(jlink_handle, 8);
 492         if (result != 8)
 493         {
 494                 LOG_ERROR("J-Link command EMU_CMD_GET_STATE failed (%d)\n", result);
 495                 return ERROR_JTAG_DEVICE_ERROR;
 496         }
 497
 498         int vref = usb_in_buffer[0] + (usb_in_buffer[1] << 8);
 499         LOG_INFO("Vref = %d.%d TCK = %d TDI = %d TDO = %d TMS = %d SRST = %d TRST = %d\n", \
 500                 vref / 1000, vref % 1000, \
 501                 usb_in_buffer[2], usb_in_buffer[3], usb_in_buffer[4], \
 502                 usb_in_buffer[5], usb_in_buffer[6], usb_in_buffer[7]);
 503
 504         if (vref < 1500)
 505                 LOG_ERROR("Vref too low. Check Target Power\n");
 506
 507         return ERROR_OK;
 508 }
 509
 510 static int jlink_get_version_info(void)
 511 {
 512         int result;
 513         int len;
 514         uint32_t jlink_caps, jlink_max_size;
 515
 516         /* query hardware version */
 517         jlink_simple_command(EMU_CMD_VERSION);
 518
 519         result = jlink_usb_read(jlink_handle, 2);
 520         if (2 != result)
 521         {
 522                 LOG_ERROR("J-Link command EMU_CMD_VERSION failed (%d)\n", result);
 523                 return ERROR_JTAG_DEVICE_ERROR;
 524         }
 525
 526         len = buf_get_u32(usb_in_buffer, 0, 16);
 527         if (len > JLINK_IN_BUFFER_SIZE)
 528         {
 529                 LOG_ERROR("J-Link command EMU_CMD_VERSION impossible return length 0x%0x", len);
 530                 len = JLINK_IN_BUFFER_SIZE;
 531         }
 532
 533         result = jlink_usb_read(jlink_handle, len);
 534         if (result != len)
 535         {
 536                 LOG_ERROR("J-Link command EMU_CMD_VERSION failed (%d)\n", result);
 537                 return ERROR_JTAG_DEVICE_ERROR;
 538         }
 539
 540         usb_in_buffer[result] = 0;
 541         LOG_INFO("%s", (char *)usb_in_buffer);
 542
 543         /* query hardware capabilities */
 544         jlink_simple_command(EMU_CMD_GET_CAPS);
 545
 546         result = jlink_usb_read(jlink_handle, 4);
 547         if (4 != result)
 548         {
 549                 LOG_ERROR("J-Link command EMU_CMD_GET_CAPS failed (%d)\n", result);
 550                 return ERROR_JTAG_DEVICE_ERROR;
 551         }
 552
 553         jlink_caps = buf_get_u32(usb_in_buffer, 0, 32);
 554         LOG_INFO("JLink caps 0x%x", (unsigned)jlink_caps);
 555
 556         if (jlink_caps & (1 << EMU_CAP_GET_HW_VERSION))
 557         {
 558                 /* query hardware version */
 559                 jlink_simple_command(EMU_CMD_GET_HW_VERSION);
 560
 561                 result = jlink_usb_read(jlink_handle, 4);
 562                 if (4 != result)
 563                 {
 564                         LOG_ERROR("J-Link command EMU_CMD_GET_HW_VERSION failed (%d)\n", result);
 565                         return ERROR_JTAG_DEVICE_ERROR;
 566                 }
 567
 568                 uint32_t jlink_hw_version = buf_get_u32(usb_in_buffer, 0, 32);
 569                 uint32_t major_revision = (jlink_hw_version / 10000) % 100;
 570                 if (major_revision >= 5)
 571                         jlink_hw_jtag_version = 3;
 572
 573                 LOG_INFO("JLink hw version %i", (int)jlink_hw_version);
 574         }
 575
 576         if (jlink_caps & (1 << EMU_CAP_GET_MAX_BLOCK_SIZE))
 577         {
 578                 /* query hardware maximum memory block */
 579                 jlink_simple_command(EMU_CMD_GET_MAX_MEM_BLOCK);
 580
 581                 result = jlink_usb_read(jlink_handle, 4);
 582                 if (4 != result)
 583                 {
 584                         LOG_ERROR("J-Link command EMU_CMD_GET_MAX_MEM_BLOCK failed (%d)\n", result);
 585                         return ERROR_JTAG_DEVICE_ERROR;
 586                 }
 587
 588                 jlink_max_size = buf_get_u32(usb_in_buffer, 0, 32);
 589                 LOG_INFO("JLink max mem block %i", (int)jlink_max_size);
 590         }
 591
 592         return ERROR_OK;
 593 }
 594
 595 COMMAND_HANDLER(jlink_handle_jlink_info_command)
 596 {
 597         if (jlink_get_version_info() == ERROR_OK)
 598         {
 599                 /* attempt to get status */
 600                 jlink_get_status();
 601         }
 602
 603         return ERROR_OK;
 604 }
 605
 606 COMMAND_HANDLER(jlink_handle_jlink_hw_jtag_command)
 607 {
 608         switch (CMD_ARGC) {
 609         case 0:
 610                 command_print(CMD_CTX, "jlink hw jtag  %i", jlink_hw_jtag_version);
 611                 break;
 612         case 1: {
 613                 int request_version = atoi(CMD_ARGV[0]);
 614                 switch (request_version) {
 615                 case 2: case 3:
 616                         jlink_hw_jtag_version = request_version;
 617                         break;
 618                 default:
 619                         return ERROR_COMMAND_SYNTAX_ERROR;
 620                 }
 621                 break;
 622         }
 623         default:
 624                 return ERROR_COMMAND_SYNTAX_ERROR;
 625         }
 626
 627         return ERROR_OK;
 628 }
 629
 630 static const struct command_registration jlink_command_handlers[] = {
 631         {
 632                 .name = "jlink_info",
 633                 .handler = &jlink_handle_jlink_info_command,
 634                 .mode = COMMAND_EXEC,
 635                 .help = "show jlink info",
 636         },
 637         {
 638                 .name = "jlink_hw_jtag",
 639                 .handler = &jlink_handle_jlink_hw_jtag_command,
 640                 .mode = COMMAND_EXEC,
 641                 .help = "access J-Link HW JTAG command version",
 642                 .usage = "[2|3]",
 643         },
 644         COMMAND_REGISTRATION_DONE
 645 };
 646
 647 struct jtag_interface jlink_interface = {
 648         .name = "jlink",
 649         .commands = jlink_command_handlers,
 650
 651         .execute_queue = jlink_execute_queue,
 652         .speed = jlink_speed,
 653         .speed_div = jlink_speed_div,
 654         .khz = jlink_khz,
 655         .init = jlink_init,
 656         .quit = jlink_quit,
 657 };
 658
 659 /***************************************************************************/
 660 /* J-Link tap functions */
 661
 662
 663 static unsigned tap_length = 0;
 664 static uint8_t tms_buffer[JLINK_TAP_BUFFER_SIZE];
 665 static uint8_t tdi_buffer[JLINK_TAP_BUFFER_SIZE];
 666 static uint8_t tdo_buffer[JLINK_TAP_BUFFER_SIZE];
 667
 668 struct pending_scan_result {
 669         int first;      /* First bit position in tdo_buffer to read */
 670         int length; /* Number of bits to read */
 671         struct scan_command *command; /* Corresponding scan command */
 672         uint8_t *buffer;
 673 };
 674
 675 #define MAX_PENDING_SCAN_RESULTS 256
 676
 677 static int pending_scan_results_length;
 678 static struct pending_scan_result pending_scan_results_buffer[MAX_PENDING_SCAN_RESULTS];
 679
 680 static void jlink_tap_init(void)
 681 {
 682         tap_length = 0;
 683         pending_scan_results_length = 0;
 684 }
 685
 686 static void jlink_tap_ensure_space(int scans, int bits)
 687 {
 688         int available_scans = MAX_PENDING_SCAN_RESULTS - pending_scan_results_length;
 689         int available_bits = JLINK_TAP_BUFFER_SIZE * 8 - tap_length - 32;
 690
 691         if (scans > available_scans || bits > available_bits)
 692         {
 693                 jlink_tap_execute();
 694         }
 695 }
 696
 697 static void jlink_tap_append_step(int tms, int tdi)
 698 {
 699         int index = tap_length / 8;
 700
 701         if (index >= JLINK_TAP_BUFFER_SIZE)
 702         {
 703                 LOG_ERROR("jlink_tap_append_step: overflow");
 704                 *(uint32_t *)0xFFFFFFFF = 0;
 705                 exit(-1);
 706         }
 707
 708         int bit_index = tap_length % 8;
 709         uint8_t bit = 1 << bit_index;
 710
 711         // we do not pad TMS, so be sure to initialize all bits
 712         if (0 == bit_index)
 713         {
 714                 tms_buffer[index] = tdi_buffer[index] = 0;
 715         }
 716
 717         if (tms)
 718                 tms_buffer[index] |= bit;
 719         else
 720                 tms_buffer[index] &= ~bit;
 721
 722         if (tdi)
 723                 tdi_buffer[index] |= bit;
 724         else
 725                 tdi_buffer[index] &= ~bit;
 726
 727         tap_length++;
 728 }
 729
 730 static void jlink_tap_append_scan(int length, uint8_t *buffer, struct scan_command *command)
 731 {
 732         struct pending_scan_result *pending_scan_result =
 733                 &pending_scan_results_buffer[pending_scan_results_length];
 734         int i;
 735
 736         pending_scan_result->first = tap_length;
 737         pending_scan_result->length = length;
 738         pending_scan_result->command = command;
 739         pending_scan_result->buffer = buffer;
 740
 741         for (i = 0; i < length; i++)
 742         {
 743                 int tms = (i < (length - 1)) ? 0 : 1;
 744                 int tdi = (buffer[i / 8] & (1 << (i % 8))) != 0;
 745                 jlink_tap_append_step(tms, tdi);
 746         }
 747         pending_scan_results_length++;
 748 }
 749
 750 /* Pad and send a tap sequence to the device, and receive the answer.
 751  * For the purpose of padding we assume that we are in idle or pause state. */
 752 static int jlink_tap_execute(void)
 753 {
 754         int byte_length;
 755         int i;
 756         int result;
 757
 758         if (!tap_length)
 759                 return ERROR_OK;
 760
 761         /* JLink returns an extra NULL in packet when size of incoming
 762          * message is a multiple of 64, creates problems with USB comms.
 763          * WARNING: This will interfere with tap state counting. */
 764         while ((DIV_ROUND_UP(tap_length, 8) % 64) == 0)
 765         {
 766                 jlink_tap_append_step((tap_get_state() == TAP_RESET)?1:0, 0);
 767         }
 768
 769         // number of full bytes (plus one if some would be left over)
 770         byte_length = DIV_ROUND_UP(tap_length, 8);
 771
 772         bool use_jtag3 = jlink_hw_jtag_version >= 3;
 773         usb_out_buffer[0] = use_jtag3 ? EMU_CMD_HW_JTAG3 : EMU_CMD_HW_JTAG2;
 774         usb_out_buffer[1] = 0;
 775         usb_out_buffer[2] = (tap_length >> 0) & 0xff;
 776         usb_out_buffer[3] = (tap_length >> 8) & 0xff;
 777         memcpy(usb_out_buffer + 4, tms_buffer, byte_length);
 778         memcpy(usb_out_buffer + 4 + byte_length, tdi_buffer, byte_length);
 779
 780         jlink_last_state = jtag_debug_state_machine(tms_buffer, tdi_buffer,
 781                         tap_length, jlink_last_state);
 782
 783         result = jlink_usb_message(jlink_handle, 4 + 2 * byte_length, byte_length);
 784         if (result != byte_length)
 785         {
 786                 LOG_ERROR("jlink_tap_execute, wrong result %d (expected %d)", result, byte_length);
 787                 jlink_tap_init();
 788                 return ERROR_JTAG_QUEUE_FAILED;
 789         }
 790
 791         memcpy(tdo_buffer, usb_in_buffer, byte_length);
 792
 793         for (i = 0; i < pending_scan_results_length; i++)
 794         {
 795                 struct pending_scan_result *pending_scan_result = &pending_scan_results_buffer[i];
 796                 uint8_t *buffer = pending_scan_result->buffer;
 797                 int length = pending_scan_result->length;
 798                 int first = pending_scan_result->first;
 799                 struct scan_command *command = pending_scan_result->command;
 800
 801                 /* Copy to buffer */
 802                 buf_set_buf(tdo_buffer, first, buffer, 0, length);
 803
 804                 DEBUG_JTAG_IO("pending scan result, length = %d", length);
 805
 806 #ifdef _DEBUG_USB_COMMS_
 807                 jlink_debug_buffer(buffer, DIV_ROUND_UP(length, 8));
 808 #endif
 809
 810                 if (jtag_read_buffer(buffer, command) != ERROR_OK)
 811                 {
 812                         jlink_tap_init();
 813                         return ERROR_JTAG_QUEUE_FAILED;
 814                 }
 815
 816                 if (pending_scan_result->buffer != NULL)
 817                 {
 818                         free(pending_scan_result->buffer);
 819                 }
 820         }
 821
 822         jlink_tap_init();
 823         return ERROR_OK;
 824 }
 825
 826 /*****************************************************************************/
 827 /* JLink USB low-level functions */
 828
 829 static struct jlink* jlink_usb_open()
 830 {
 831         usb_init();
 832
 833         const uint16_t vids[] = { VID, 0 };
 834         const uint16_t pids[] = { PID, 0 };
 835         struct usb_dev_handle *dev;
 836         if (jtag_usb_open(vids, pids, &dev) != ERROR_OK)
 837                 return NULL;
 838
 839         /* BE ***VERY CAREFUL*** ABOUT MAKING CHANGES IN THIS
 840          * AREA!!!!!!!!!!!  The behavior of libusb is not completely
 841          * consistent across Windows, Linux, and Mac OS X platforms.
 842          * The actions taken in the following compiler conditionals may
 843          * not agree with published documentation for libusb, but were
 844          * found to be necessary through trials and tribulations.  Even
 845          * little tweaks can break one or more platforms, so if you do
 846          * make changes test them carefully on all platforms before
 847          * committing them!
 848          */
 849
 850 #if IS_WIN32 == 0
 851
 852         usb_reset(dev);
 853
 854 #if IS_DARWIN == 0
 855
 856         int timeout = 5;
 857         /* reopen jlink after usb_reset
 858          * on win32 this may take a second or two to re-enumerate */
 859         int retval;
 860         while ((retval = jtag_usb_open(vids, pids, &dev)) != ERROR_OK)
 861         {
 862                 usleep(1000);
 863                 timeout--;
 864                 if (!timeout) {
 865                         break;
 866                 }
 867         }
 868         if (ERROR_OK != retval)
 869                 return NULL;
 870 #endif
 871
 872 #endif
 873
 874         /* usb_set_configuration required under win32 */
 875         struct usb_device *udev = usb_device(dev);
 876         usb_set_configuration(dev, udev->config[0].bConfigurationValue);
 877         usb_claim_interface(dev, 0);
 878
 879 #if 0
 880         /*
 881          * This makes problems under Mac OS X. And is not needed
 882          * under Windows. Hopefully this will not break a linux build
 883          */
 884         usb_set_altinterface(result->usb_handle, 0);
 885 #endif
 886         struct usb_interface *iface = udev->config->interface;
 887         struct usb_interface_descriptor *desc = iface->altsetting;
 888         for (int i = 0; i < desc->bNumEndpoints; i++)
 889         {
 890                 uint8_t epnum = desc->endpoint[i].bEndpointAddress;
 891                 bool is_input = epnum & 0x80;
 892                 LOG_DEBUG("usb ep %s %02x", is_input ? "in" : "out", epnum);
 893                 if (is_input)
 894                         jlink_read_ep = epnum;
 895                 else
 896                         jlink_write_ep = epnum;
 897         }
 898
 899         struct jlink *result = malloc(sizeof(struct jlink));
 900         result->usb_handle = dev;
 901         return result;
 902 }
 903
 904 static void jlink_usb_close(struct jlink *jlink)
 905 {
 906         usb_close(jlink->usb_handle);
 907         free(jlink);
 908 }
 909
 910 /* Send a message and receive the reply. */
 911 static int jlink_usb_message(struct jlink *jlink, int out_length, int in_length)
 912 {
 913         int result;
 914
 915         result = jlink_usb_write(jlink, out_length);
 916         if (result != out_length)
 917         {
 918                 LOG_ERROR("usb_bulk_write failed (requested=%d, result=%d)",
 919                                 out_length, result);
 920                 return ERROR_JTAG_DEVICE_ERROR;
 921         }
 922
 923         result = jlink_usb_read(jlink, in_length);
 924         if ((result != in_length) && (result != (in_length + 1)))
 925         {
 926                 LOG_ERROR("usb_bulk_read failed (requested=%d, result=%d)",
 927                                 in_length, result);
 928                 return ERROR_JTAG_DEVICE_ERROR;
 929         }
 930
 931         if (jlink_hw_jtag_version < 3)
 932                 return result;
 933
 934         int result2 = ERROR_OK;
 935         if (result == in_length)
 936         {
 937                 /* Must read the result from the EMU too */
 938                 result2 = jlink_usb_read_emu_result(jlink);
 939                 if (1 != result2)
 940                 {
 941                         LOG_ERROR("jlink_usb_read_emu_result retried requested = 1, result=%d, in_length=%i", result2,in_length);
 942                         /* Try again once, should only happen if (in_length%64 == 0) */
 943                         result2 = jlink_usb_read_emu_result(jlink);
 944                         if (1 != result2)
 945                         {
 946                                 LOG_ERROR("jlink_usb_read_emu_result failed "
 947                                         "(requested = 1, result=%d)", result2);
 948                                 return ERROR_JTAG_DEVICE_ERROR;
 949                         }
 950                 }
 951
 952                 /* Check the result itself */
 953                 result2 = usb_emu_result_buffer[0];
 954         }
 955         else
 956         {
 957                 /* Save the result, then remove it from return value */
 958                 result2 = usb_in_buffer[result--];
 959         }
 960
 961         if (result2)
 962         {
 963                 LOG_ERROR("jlink_usb_message failed with result=%d)", result2);
 964                 return ERROR_JTAG_DEVICE_ERROR;
 965         }
 966
 967         return result;
 968 }
 969
 970 /* calls the given usb_bulk_* function, allowing for the data to trickle in with some timeouts  */
 971 static int usb_bulk_with_retries(
 972                 int (*f)(usb_dev_handle *, int, char *, int, int),
 973                 usb_dev_handle *dev, int ep,
 974                 char *bytes, int size, int timeout)
 975 {
 976         int tries = 3, count = 0;
 977
 978         while (tries && (count < size))
 979         {
 980                 int result = f(dev, ep, bytes + count, size - count, timeout);
 981                 if (result > 0)
 982                         count += result;
 983                 else if ((-ETIMEDOUT != result) || !--tries)
 984                         return result;
 985         }
 986         return count;
 987 }
 988
 989 static int wrap_usb_bulk_write(usb_dev_handle *dev, int ep,
 990                                char *buff, int size, int timeout)
 991 {
 992         /* usb_bulk_write() takes const char *buff */
 993         return usb_bulk_write(dev, ep, buff, size, timeout);
 994 }
 995
 996 static inline int usb_bulk_write_ex(usb_dev_handle *dev, int ep,
 997                 char *bytes, int size, int timeout)
 998 {
 999         return usb_bulk_with_retries(&wrap_usb_bulk_write,
1000                         dev, ep, bytes, size, timeout);
1001 }
1002
1003 static inline int usb_bulk_read_ex(usb_dev_handle *dev, int ep,
1004                 char *bytes, int size, int timeout)
1005 {
1006         return usb_bulk_with_retries(&usb_bulk_read,
1007                         dev, ep, bytes, size, timeout);
1008 }
1009
1010 /* Write data from out_buffer to USB. */
1011 static int jlink_usb_write(struct jlink *jlink, int out_length)
1012 {
1013         int result;
1014
1015         if (out_length > JLINK_OUT_BUFFER_SIZE)
1016         {
1017                 LOG_ERROR("jlink_write illegal out_length=%d (max=%d)", out_length, JLINK_OUT_BUFFER_SIZE);
1018                 return -1;
1019         }
1020
1021         result = usb_bulk_write_ex(jlink->usb_handle, jlink_write_ep,
1022                 (char *)usb_out_buffer, out_length, JLINK_USB_TIMEOUT);
1023
1024         DEBUG_JTAG_IO("jlink_usb_write, out_length = %d, result = %d", out_length, result);
1025
1026 #ifdef _DEBUG_USB_COMMS_
1027         jlink_debug_buffer(usb_out_buffer, out_length);
1028 #endif
1029         return result;
1030 }
1031
1032 /* Read data from USB into in_buffer. */
1033 static int jlink_usb_read(struct jlink *jlink, int expected_size)
1034 {
1035         int result = usb_bulk_read_ex(jlink->usb_handle, jlink_read_ep,
1036                 (char *)usb_in_buffer, expected_size, JLINK_USB_TIMEOUT);
1037
1038         DEBUG_JTAG_IO("jlink_usb_read, result = %d", result);
1039
1040 #ifdef _DEBUG_USB_COMMS_
1041         jlink_debug_buffer(usb_in_buffer, result);
1042 #endif
1043         return result;
1044 }
1045
1046 /* Read the result from the previous EMU cmd into result_buffer. */
1047 static int jlink_usb_read_emu_result(struct jlink *jlink)
1048 {
1049         int result = usb_bulk_read_ex(jlink->usb_handle, jlink_read_ep,
1050                 (char *)usb_emu_result_buffer, 1 /* JLINK_EMU_RESULT_BUFFER_SIZE */,
1051                 JLINK_USB_TIMEOUT);
1052
1053         DEBUG_JTAG_IO("jlink_usb_read_result, result = %d", result);
1054
1055 #ifdef _DEBUG_USB_COMMS_
1056         jlink_debug_buffer(usb_emu_result_buffer, result);
1057 #endif
1058         return result;
1059 }
1060
1061 #ifdef _DEBUG_USB_COMMS_
1062 #define BYTES_PER_LINE  16
1063
1064 static void jlink_debug_buffer(uint8_t *buffer, int length)
1065 {
1066         char line[81];
1067         char s[4];
1068         int i;
1069         int j;
1070
1071         for (i = 0; i < length; i += BYTES_PER_LINE)
1072         {
1073                 snprintf(line, 5, "%04x", i);
1074                 for (j = i; j < i + BYTES_PER_LINE && j < length; j++)
1075                 {
1076                         snprintf(s, 4, " %02x", buffer[j]);
1077                         strcat(line, s);
1078                 }
1079                 LOG_DEBUG("%s", line);
1080         }
1081 }
1082 #endif
1083