git.gag.com Git - fw/openocd/blob - src/jtag/core.c

   1 /***************************************************************************
   2  *   Copyright (C) 2009 Zachary T Welch                                    *
   3  *   zw@superlucidity.net                                                  *
   4  *                                                                         *
   5  *   Copyright (C) 2007,2008,2009 Øyvind Harboe                            *
   6  *   oyvind.harboe@zylin.com                                               *
   7  *                                                                         *
   8  *   Copyright (C) 2009 SoftPLC Corporation                                *
   9  *       http://softplc.com                                                *
  10  *   dick@softplc.com                                                      *
  11  *                                                                         *
  12  *   Copyright (C) 2005 by Dominic Rath                                    *
  13  *   Dominic.Rath@gmx.de                                                   *
  14  *                                                                         *
  15  *   This program is free software; you can redistribute it and/or modify  *
  16  *   it under the terms of the GNU General Public License as published by  *
  17  *   the Free Software Foundation; either version 2 of the License, or     *
  18  *   (at your option) any later version.                                   *
  19  *                                                                         *
  20  *   This program is distributed in the hope that it will be useful,       *
  21  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  22  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  23  *   GNU General Public License for more details.                          *
  24  *                                                                         *
  25  *   You should have received a copy of the GNU General Public License     *
  26  *   along with this program; if not, write to the                         *
  27  *   Free Software Foundation, Inc.,                                       *
  28  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
  29  ***************************************************************************/
  30 #ifdef HAVE_CONFIG_H
  31 #include "config.h"
  32 #endif
  33
  34 #include "jtag.h"
  35 #include "interface.h"
  36
  37 #ifdef HAVE_STRINGS_H
  38 #include <strings.h>
  39 #endif
  40
  41
  42 /// The number of JTAG queue flushes (for profiling and debugging purposes).
  43 static int jtag_flush_queue_count;
  44
  45 static void jtag_add_scan_check(struct jtag_tap *active,
  46                 void (*jtag_add_scan)(struct jtag_tap *active, int in_num_fields, const struct scan_field *in_fields, tap_state_t state),
  47                 int in_num_fields, struct scan_field *in_fields, tap_state_t state);
  48
  49 /**
  50  * The jtag_error variable is set when an error occurs while executing
  51  * the queue.  Application code may set this using jtag_set_error(),
  52  * when an error occurs during processing that should be reported during
  53  * jtag_execute_queue().
  54  *
  55  * Tts value may be checked with jtag_get_error() and cleared with
  56  * jtag_error_clear().  This value is returned (and cleared) by
  57  * jtag_execute_queue().
  58  */
  59 static int jtag_error = ERROR_OK;
  60
  61 static const char *jtag_event_strings[] =
  62 {
  63         [JTAG_TRST_ASSERTED] = "TAP reset",
  64         [JTAG_TAP_EVENT_SETUP] = "TAP setup",
  65         [JTAG_TAP_EVENT_ENABLE] = "TAP enabled",
  66         [JTAG_TAP_EVENT_DISABLE] = "TAP disabled",
  67 };
  68
  69 /*
  70  * JTAG adapters must initialize with TRST and SRST de-asserted
  71  * (they're negative logic, so that means *high*).  But some
  72  * hardware doesn't necessarily work that way ... so set things
  73  * up so that jtag_init() always forces that state.
  74  */
  75 static int jtag_trst = -1;
  76 static int jtag_srst = -1;
  77
  78 /**
  79  * List all TAPs that have been created.
  80  */
  81 static struct jtag_tap *__jtag_all_taps = NULL;
  82 /**
  83  * The number of TAPs in the __jtag_all_taps list, used to track the
  84  * assigned chain position to new TAPs
  85  */
  86 static unsigned jtag_num_taps = 0;
  87
  88 static enum reset_types jtag_reset_config = RESET_NONE;
  89 static tap_state_t cmd_queue_end_state = TAP_RESET;
  90 tap_state_t cmd_queue_cur_state = TAP_RESET;
  91
  92 static bool jtag_verify_capture_ir = true;
  93 static int jtag_verify = 1;
  94
  95 /* how long the OpenOCD should wait before attempting JTAG communication after reset lines deasserted (in ms) */
  96 static int jtag_nsrst_delay = 0; /* default to no nSRST delay */
  97 static int jtag_ntrst_delay = 0; /* default to no nTRST delay */
  98 static int jtag_nsrst_assert_width = 0; /* width of assertion */
  99 static int jtag_ntrst_assert_width = 0; /* width of assertion */
 100
 101 /**
 102  * Contains a single callback along with a pointer that will be passed
 103  * when an event occurs.
 104  */
 105 struct jtag_event_callback {
 106         /// a event callback
 107         jtag_event_handler_t callback;
 108         /// the private data to pass to the callback
 109         void* priv;
 110         /// the next callback
 111         struct jtag_event_callback* next;
 112 };
 113
 114 /* callbacks to inform high-level handlers about JTAG state changes */
 115 static struct jtag_event_callback *jtag_event_callbacks;
 116
 117 /* speed in kHz*/
 118 static int speed_khz = 0;
 119 /* speed to fallback to when RCLK is requested but not supported */
 120 static int rclk_fallback_speed_khz = 0;
 121 static enum {CLOCK_MODE_SPEED, CLOCK_MODE_KHZ, CLOCK_MODE_RCLK} clock_mode;
 122 static int jtag_speed = 0;
 123
 124 static struct jtag_interface *jtag = NULL;
 125
 126 /* configuration */
 127 struct jtag_interface *jtag_interface = NULL;
 128
 129 void jtag_set_error(int error)
 130 {
 131         if ((error == ERROR_OK) || (jtag_error != ERROR_OK))
 132                 return;
 133         jtag_error = error;
 134 }
 135 int jtag_get_error(void)
 136 {
 137         return jtag_error;
 138 }
 139 int jtag_error_clear(void)
 140 {
 141         int temp = jtag_error;
 142         jtag_error = ERROR_OK;
 143         return temp;
 144 }
 145
 146 /************/
 147
 148 static bool jtag_poll = 1;
 149
 150 bool is_jtag_poll_safe(void)
 151 {
 152         /* Polling can be disabled explicitly with set_enabled(false).
 153          * It is also implicitly disabled while TRST is active and
 154          * while SRST is gating the JTAG clock.
 155          */
 156         if (!jtag_poll || jtag_trst != 0)
 157                 return false;
 158         return jtag_srst == 0 || (jtag_reset_config & RESET_SRST_NO_GATING);
 159 }
 160
 161 bool jtag_poll_get_enabled(void)
 162 {
 163         return jtag_poll;
 164 }
 165
 166 void jtag_poll_set_enabled(bool value)
 167 {
 168         jtag_poll = value;
 169 }
 170
 171 /************/
 172
 173 struct jtag_tap *jtag_all_taps(void)
 174 {
 175         return __jtag_all_taps;
 176 };
 177
 178 unsigned jtag_tap_count(void)
 179 {
 180         return jtag_num_taps;
 181 }
 182
 183 unsigned jtag_tap_count_enabled(void)
 184 {
 185         struct jtag_tap *t = jtag_all_taps();
 186         unsigned n = 0;
 187         while (t)
 188         {
 189                 if (t->enabled)
 190                         n++;
 191                 t = t->next_tap;
 192         }
 193         return n;
 194 }
 195
 196 /// Append a new TAP to the chain of all taps.
 197 void jtag_tap_add(struct jtag_tap *t)
 198 {
 199         t->abs_chain_position = jtag_num_taps++;
 200
 201         struct jtag_tap **tap = &__jtag_all_taps;
 202         while (*tap != NULL)
 203                 tap = &(*tap)->next_tap;
 204         *tap = t;
 205 }
 206
 207 /* returns a pointer to the n-th device in the scan chain */
 208 static inline struct jtag_tap *jtag_tap_by_position(unsigned n)
 209 {
 210         struct jtag_tap *t = jtag_all_taps();
 211
 212         while (t && n-- > 0)
 213                 t = t->next_tap;
 214
 215         return t;
 216 }
 217
 218 struct jtag_tap *jtag_tap_by_string(const char *s)
 219 {
 220         /* try by name first */
 221         struct jtag_tap *t = jtag_all_taps();
 222
 223         while (t)
 224         {
 225                 if (0 == strcmp(t->dotted_name, s))
 226                         return t;
 227                 t = t->next_tap;
 228         }
 229
 230         /* no tap found by name, so try to parse the name as a number */
 231         unsigned n;
 232         if (parse_uint(s, &n) != ERROR_OK)
 233                 return NULL;
 234
 235         /* FIXME remove this numeric fallback code late June 2010, along
 236          * with all info in the User's Guide that TAPs have numeric IDs.
 237          * Also update "scan_chain" output to not display the numbers.
 238          */
 239         t = jtag_tap_by_position(n);
 240         if (t)
 241                 LOG_WARNING("Specify TAP '%s' by name, not number %u",
 242                         t->dotted_name, n);
 243
 244         return t;
 245 }
 246
 247 struct jtag_tap* jtag_tap_next_enabled(struct jtag_tap* p)
 248 {
 249         p = p ? p->next_tap : jtag_all_taps();
 250         while (p)
 251         {
 252                 if (p->enabled)
 253                         return p;
 254                 p = p->next_tap;
 255         }
 256         return NULL;
 257 }
 258
 259 const char *jtag_tap_name(const struct jtag_tap *tap)
 260 {
 261         return (tap == NULL) ? "(unknown)" : tap->dotted_name;
 262 }
 263
 264
 265 int jtag_register_event_callback(jtag_event_handler_t callback, void *priv)
 266 {
 267         struct jtag_event_callback **callbacks_p = &jtag_event_callbacks;
 268
 269         if (callback == NULL)
 270         {
 271                 return ERROR_INVALID_ARGUMENTS;
 272         }
 273
 274         if (*callbacks_p)
 275         {
 276                 while ((*callbacks_p)->next)
 277                         callbacks_p = &((*callbacks_p)->next);
 278                 callbacks_p = &((*callbacks_p)->next);
 279         }
 280
 281         (*callbacks_p) = malloc(sizeof(struct jtag_event_callback));
 282         (*callbacks_p)->callback = callback;
 283         (*callbacks_p)->priv = priv;
 284         (*callbacks_p)->next = NULL;
 285
 286         return ERROR_OK;
 287 }
 288
 289 int jtag_unregister_event_callback(jtag_event_handler_t callback, void *priv)
 290 {
 291         struct jtag_event_callback **callbacks_p;
 292         struct jtag_event_callback **next;
 293
 294         if (callback == NULL)
 295         {
 296                 return ERROR_INVALID_ARGUMENTS;
 297         }
 298
 299         for (callbacks_p = &jtag_event_callbacks;
 300                         *callbacks_p != NULL;
 301                         callbacks_p = next)
 302         {
 303                 next = &((*callbacks_p)->next);
 304
 305                 if ((*callbacks_p)->priv != priv)
 306                         continue;
 307
 308                 if ((*callbacks_p)->callback == callback)
 309                 {
 310                         free(*callbacks_p);
 311                         *callbacks_p = *next;
 312                 }
 313         }
 314
 315         return ERROR_OK;
 316 }
 317
 318 int jtag_call_event_callbacks(enum jtag_event event)
 319 {
 320         struct jtag_event_callback *callback = jtag_event_callbacks;
 321
 322         LOG_DEBUG("jtag event: %s", jtag_event_strings[event]);
 323
 324         while (callback)
 325         {
 326                 struct jtag_event_callback *next;
 327
 328                 /* callback may remove itself */
 329                 next = callback->next;
 330                 callback->callback(event, callback->priv);
 331                 callback = next;
 332         }
 333
 334         return ERROR_OK;
 335 }
 336
 337 static void jtag_checks(void)
 338 {
 339         assert(jtag_trst == 0);
 340 }
 341
 342 static void jtag_prelude(tap_state_t state)
 343 {
 344         jtag_checks();
 345
 346         assert(state != TAP_INVALID);
 347
 348         cmd_queue_cur_state = state;
 349 }
 350
 351 void jtag_alloc_in_value32(struct scan_field *field)
 352 {
 353         interface_jtag_alloc_in_value32(field);
 354 }
 355
 356 void jtag_add_ir_scan_noverify(struct jtag_tap *active, const struct scan_field *in_fields,
 357                 tap_state_t state)
 358 {
 359         jtag_prelude(state);
 360
 361         int retval = interface_jtag_add_ir_scan(active, in_fields, state);
 362         jtag_set_error(retval);
 363 }
 364
 365 static void jtag_add_ir_scan_noverify_callback(struct jtag_tap *active, int dummy, const struct scan_field *in_fields,
 366                 tap_state_t state)
 367 {
 368         jtag_add_ir_scan_noverify(active, in_fields, state);
 369 }
 370
 371 void jtag_add_ir_scan(struct jtag_tap *active, struct scan_field *in_fields, tap_state_t state)
 372 {
 373         assert(state != TAP_RESET);
 374
 375         if (jtag_verify && jtag_verify_capture_ir)
 376         {
 377                 /* 8 x 32 bit id's is enough for all invocations */
 378
 379                 /* if we are to run a verification of the ir scan, we need to get the input back.
 380                  * We may have to allocate space if the caller didn't ask for the input back.
 381                  */
 382                 in_fields->check_value = active->expected;
 383                 in_fields->check_mask = active->expected_mask;
 384                 jtag_add_scan_check(active, jtag_add_ir_scan_noverify_callback, 1, in_fields, state);
 385         } else
 386         {
 387                 jtag_add_ir_scan_noverify(active, in_fields, state);
 388         }
 389 }
 390
 391 void jtag_add_plain_ir_scan(int in_num_fields, const struct scan_field *in_fields,
 392                 tap_state_t state)
 393 {
 394         assert(state != TAP_RESET);
 395
 396         jtag_prelude(state);
 397
 398         int retval = interface_jtag_add_plain_ir_scan(
 399                         in_num_fields, in_fields, state);
 400         jtag_set_error(retval);
 401 }
 402
 403 static int jtag_check_value_inner(uint8_t *captured, uint8_t *in_check_value,
 404                 uint8_t *in_check_mask, int num_bits);
 405
 406 static int jtag_check_value_mask_callback(jtag_callback_data_t data0, jtag_callback_data_t data1, jtag_callback_data_t data2, jtag_callback_data_t data3)
 407 {
 408         return jtag_check_value_inner((uint8_t *)data0, (uint8_t *)data1, (uint8_t *)data2, (int)data3);
 409 }
 410
 411 static void jtag_add_scan_check(struct jtag_tap *active, void (*jtag_add_scan)(struct jtag_tap *active, int in_num_fields, const struct scan_field *in_fields, tap_state_t state),
 412                 int in_num_fields, struct scan_field *in_fields, tap_state_t state)
 413 {
 414         for (int i = 0; i < in_num_fields; i++)
 415         {
 416                 struct scan_field *field = &in_fields[i];
 417                 field->allocated = 0;
 418                 field->modified = 0;
 419                 if (field->check_value || field->in_value)
 420                         continue;
 421                 interface_jtag_add_scan_check_alloc(field);
 422                 field->modified = 1;
 423         }
 424
 425         jtag_add_scan(active, in_num_fields, in_fields, state);
 426
 427         for (int i = 0; i < in_num_fields; i++)
 428         {
 429                 if ((in_fields[i].check_value != NULL) && (in_fields[i].in_value != NULL))
 430                 {
 431                         /* this is synchronous for a minidriver */
 432                         jtag_add_callback4(jtag_check_value_mask_callback, (jtag_callback_data_t)in_fields[i].in_value,
 433                                 (jtag_callback_data_t)in_fields[i].check_value,
 434                                 (jtag_callback_data_t)in_fields[i].check_mask,
 435                                 (jtag_callback_data_t)in_fields[i].num_bits);
 436                 }
 437                 if (in_fields[i].allocated)
 438                 {
 439                         free(in_fields[i].in_value);
 440                 }
 441                 if (in_fields[i].modified)
 442                 {
 443                         in_fields[i].in_value = NULL;
 444                 }
 445         }
 446 }
 447
 448 void jtag_add_dr_scan_check(struct jtag_tap *active, int in_num_fields, struct scan_field *in_fields, tap_state_t state)
 449 {
 450         if (jtag_verify)
 451         {
 452                 jtag_add_scan_check(active, jtag_add_dr_scan, in_num_fields, in_fields, state);
 453         } else
 454         {
 455                 jtag_add_dr_scan(active, in_num_fields, in_fields, state);
 456         }
 457 }
 458
 459
 460 void jtag_add_dr_scan(struct jtag_tap *active, int in_num_fields, const struct scan_field *in_fields,
 461                 tap_state_t state)
 462 {
 463         assert(state != TAP_RESET);
 464
 465         jtag_prelude(state);
 466
 467         int retval;
 468         retval = interface_jtag_add_dr_scan(active, in_num_fields, in_fields, state);
 469         jtag_set_error(retval);
 470 }
 471
 472 void jtag_add_plain_dr_scan(int in_num_fields, const struct scan_field *in_fields,
 473                 tap_state_t state)
 474 {
 475         assert(state != TAP_RESET);
 476
 477         jtag_prelude(state);
 478
 479         int retval;
 480         retval = interface_jtag_add_plain_dr_scan(in_num_fields, in_fields, state);
 481         jtag_set_error(retval);
 482 }
 483
 484 void jtag_add_tlr(void)
 485 {
 486         jtag_prelude(TAP_RESET);
 487         jtag_set_error(interface_jtag_add_tlr());
 488
 489         /* NOTE: order here matches TRST path in jtag_add_reset() */
 490         jtag_call_event_callbacks(JTAG_TRST_ASSERTED);
 491         jtag_notify_event(JTAG_TRST_ASSERTED);
 492 }
 493
 494 /**
 495  * If supported by the underlying adapter, this clocks a raw bit sequence
 496  * onto TMS for switching betwen JTAG and SWD modes.
 497  *
 498  * DO NOT use this to bypass the integrity checks and logging provided
 499  * by the jtag_add_pathmove() and jtag_add_statemove() calls.
 500  *
 501  * @param nbits How many bits to clock out.
 502  * @param seq The bit sequence.  The LSB is bit 0 of seq[0].
 503  * @param state The JTAG tap state to record on completion.  Use
 504  *      TAP_INVALID to represent being in in SWD mode.
 505  *
 506  * @todo Update naming conventions to stop assuming everything is JTAG.
 507  */
 508 int jtag_add_tms_seq(unsigned nbits, const uint8_t *seq, enum tap_state state)
 509 {
 510         int retval;
 511
 512         if (!(jtag->supported & DEBUG_CAP_TMS_SEQ))
 513                 return ERROR_JTAG_NOT_IMPLEMENTED;
 514
 515         jtag_checks();
 516         cmd_queue_cur_state = state;
 517
 518         retval = interface_add_tms_seq(nbits, seq, state);
 519         jtag_set_error(retval);
 520         return retval;
 521 }
 522
 523 void jtag_add_pathmove(int num_states, const tap_state_t *path)
 524 {
 525         tap_state_t cur_state = cmd_queue_cur_state;
 526
 527         /* the last state has to be a stable state */
 528         if (!tap_is_state_stable(path[num_states - 1]))
 529         {
 530                 LOG_ERROR("BUG: TAP path doesn't finish in a stable state");
 531                 jtag_set_error(ERROR_JTAG_NOT_STABLE_STATE);
 532                 return;
 533         }
 534
 535         for (int i = 0; i < num_states; i++)
 536         {
 537                 if (path[i] == TAP_RESET)
 538                 {
 539                         LOG_ERROR("BUG: TAP_RESET is not a valid state for pathmove sequences");
 540                         jtag_set_error(ERROR_JTAG_STATE_INVALID);
 541                         return;
 542                 }
 543
 544                 if (tap_state_transition(cur_state, true)  != path[i]
 545                   && tap_state_transition(cur_state, false) != path[i])
 546                 {
 547                         LOG_ERROR("BUG: %s -> %s isn't a valid TAP transition",
 548                                         tap_state_name(cur_state), tap_state_name(path[i]));
 549                         jtag_set_error(ERROR_JTAG_TRANSITION_INVALID);
 550                         return;
 551                 }
 552                 cur_state = path[i];
 553         }
 554
 555         jtag_checks();
 556
 557         jtag_set_error(interface_jtag_add_pathmove(num_states, path));
 558         cmd_queue_cur_state = path[num_states - 1];
 559 }
 560
 561 int jtag_add_statemove(tap_state_t goal_state)
 562 {
 563         tap_state_t cur_state = cmd_queue_cur_state;
 564
 565         if (goal_state != cur_state)
 566         {
 567                 LOG_DEBUG("cur_state=%s goal_state=%s",
 568                         tap_state_name(cur_state),
 569                         tap_state_name(goal_state));
 570         }
 571
 572         /* If goal is RESET, be paranoid and force that that transition
 573          * (e.g. five TCK cycles, TMS high).  Else trust "cur_state".
 574          */
 575         if (goal_state == TAP_RESET)
 576                 jtag_add_tlr();
 577         else if (goal_state == cur_state)
 578                 /* nothing to do */ ;
 579
 580         else if (tap_is_state_stable(cur_state) && tap_is_state_stable(goal_state))
 581         {
 582                 unsigned tms_bits  = tap_get_tms_path(cur_state, goal_state);
 583                 unsigned tms_count = tap_get_tms_path_len(cur_state, goal_state);
 584                 tap_state_t moves[8];
 585                 assert(tms_count < ARRAY_SIZE(moves));
 586
 587                 for (unsigned i = 0; i < tms_count; i++, tms_bits >>= 1)
 588                 {
 589                         bool bit = tms_bits & 1;
 590
 591                         cur_state = tap_state_transition(cur_state, bit);
 592                         moves[i] = cur_state;
 593                 }
 594
 595                 jtag_add_pathmove(tms_count, moves);
 596         }
 597         else if (tap_state_transition(cur_state, true)  == goal_state
 598                 ||   tap_state_transition(cur_state, false) == goal_state)
 599         {
 600                 jtag_add_pathmove(1, &goal_state);
 601         }
 602
 603         else
 604                 return ERROR_FAIL;
 605
 606         return ERROR_OK;
 607 }
 608
 609 void jtag_add_runtest(int num_cycles, tap_state_t state)
 610 {
 611         jtag_prelude(state);
 612         jtag_set_error(interface_jtag_add_runtest(num_cycles, state));
 613 }
 614
 615
 616 void jtag_add_clocks(int num_cycles)
 617 {
 618         if (!tap_is_state_stable(cmd_queue_cur_state))
 619         {
 620                  LOG_ERROR("jtag_add_clocks() called with TAP in unstable state \"%s\"",
 621                                  tap_state_name(cmd_queue_cur_state));
 622                  jtag_set_error(ERROR_JTAG_NOT_STABLE_STATE);
 623                  return;
 624         }
 625
 626         if (num_cycles > 0)
 627         {
 628                 jtag_checks();
 629                 jtag_set_error(interface_jtag_add_clocks(num_cycles));
 630         }
 631 }
 632
 633 void jtag_add_reset(int req_tlr_or_trst, int req_srst)
 634 {
 635         int trst_with_tlr = 0;
 636         int new_srst = 0;
 637         int new_trst = 0;
 638
 639         /* Without SRST, we must use target-specific JTAG operations
 640          * on each target; callers should not be requesting SRST when
 641          * that signal doesn't exist.
 642          *
 643          * RESET_SRST_PULLS_TRST is a board or chip level quirk, which
 644          * can kick in even if the JTAG adapter can't drive TRST.
 645          */
 646         if (req_srst) {
 647                 if (!(jtag_reset_config & RESET_HAS_SRST)) {
 648                         LOG_ERROR("BUG: can't assert SRST");
 649                         jtag_set_error(ERROR_FAIL);
 650                         return;
 651                 }
 652                 if ((jtag_reset_config & RESET_SRST_PULLS_TRST) != 0
 653                                 && !req_tlr_or_trst) {
 654                         LOG_ERROR("BUG: can't assert only SRST");
 655                         jtag_set_error(ERROR_FAIL);
 656                         return;
 657                 }
 658                 new_srst = 1;
 659         }
 660
 661         /* JTAG reset (entry to TAP_RESET state) can always be achieved
 662          * using TCK and TMS; that may go through a TAP_{IR,DR}UPDATE
 663          * state first.  TRST accelerates it, and bypasses those states.
 664          *
 665          * RESET_TRST_PULLS_SRST is a board or chip level quirk, which
 666          * can kick in even if the JTAG adapter can't drive SRST.
 667          */
 668         if (req_tlr_or_trst) {
 669                 if (!(jtag_reset_config & RESET_HAS_TRST))
 670                         trst_with_tlr = 1;
 671                 else if ((jtag_reset_config & RESET_TRST_PULLS_SRST) != 0
 672                                 && !req_srst)
 673                         trst_with_tlr = 1;
 674                 else
 675                         new_trst = 1;
 676         }
 677
 678         /* Maybe change TRST and/or SRST signal state */
 679         if (jtag_srst != new_srst || jtag_trst != new_trst) {
 680                 int retval;
 681
 682                 retval = interface_jtag_add_reset(new_trst, new_srst);
 683                 if (retval != ERROR_OK)
 684                         jtag_set_error(retval);
 685                 else
 686                         retval = jtag_execute_queue();
 687
 688                 if (retval != ERROR_OK) {
 689                         LOG_ERROR("TRST/SRST error %d", retval);
 690                         return;
 691                 }
 692         }
 693
 694         /* SRST resets everything hooked up to that signal */
 695         if (jtag_srst != new_srst) {
 696                 jtag_srst = new_srst;
 697                 if (jtag_srst)
 698                 {
 699                         LOG_DEBUG("SRST line asserted");
 700                         if (jtag_nsrst_assert_width)
 701                                 jtag_add_sleep(jtag_nsrst_assert_width * 1000);
 702                 }
 703                 else {
 704                         LOG_DEBUG("SRST line released");
 705                         if (jtag_nsrst_delay)
 706                                 jtag_add_sleep(jtag_nsrst_delay * 1000);
 707                 }
 708         }
 709
 710         /* Maybe enter the JTAG TAP_RESET state ...
 711          *  - using only TMS, TCK, and the JTAG state machine
 712          *  - or else more directly, using TRST
 713          *
 714          * TAP_RESET should be invisible to non-debug parts of the system.
 715          */
 716         if (trst_with_tlr) {
 717                 LOG_DEBUG("JTAG reset with TLR instead of TRST");
 718                 jtag_set_end_state(TAP_RESET);
 719                 jtag_add_tlr();
 720
 721         } else if (jtag_trst != new_trst) {
 722                 jtag_trst = new_trst;
 723                 if (jtag_trst) {
 724                         LOG_DEBUG("TRST line asserted");
 725                         tap_set_state(TAP_RESET);
 726                         if (jtag_ntrst_assert_width)
 727                                 jtag_add_sleep(jtag_ntrst_assert_width * 1000);
 728                 } else {
 729                         LOG_DEBUG("TRST line released");
 730                         if (jtag_ntrst_delay)
 731                                 jtag_add_sleep(jtag_ntrst_delay * 1000);
 732
 733                         /* We just asserted nTRST, so we're now in TAP_RESET.
 734                          * Inform possible listeners about this, now that
 735                          * JTAG instructions and data can be shifted.  This
 736                          * sequence must match jtag_add_tlr().
 737                          */
 738                         jtag_call_event_callbacks(JTAG_TRST_ASSERTED);
 739                         jtag_notify_event(JTAG_TRST_ASSERTED);
 740                 }
 741         }
 742 }
 743
 744 tap_state_t jtag_set_end_state(tap_state_t state)
 745 {
 746         if ((state == TAP_DRSHIFT)||(state == TAP_IRSHIFT))
 747         {
 748                 LOG_ERROR("BUG: TAP_DRSHIFT/IRSHIFT can't be end state. Calling code should use a larger scan field");
 749         }
 750
 751         if (state != TAP_INVALID)
 752                 cmd_queue_end_state = state;
 753         return cmd_queue_end_state;
 754 }
 755
 756 tap_state_t jtag_get_end_state(void)
 757 {
 758         return cmd_queue_end_state;
 759 }
 760
 761 void jtag_add_sleep(uint32_t us)
 762 {
 763         /// @todo Here, keep_alive() appears to be a layering violation!!!
 764         keep_alive();
 765         jtag_set_error(interface_jtag_add_sleep(us));
 766 }
 767
 768 static int jtag_check_value_inner(uint8_t *captured, uint8_t *in_check_value,
 769                 uint8_t *in_check_mask, int num_bits)
 770 {
 771         int retval = ERROR_OK;
 772         int compare_failed;
 773
 774         if (in_check_mask)
 775                 compare_failed = buf_cmp_mask(captured, in_check_value, in_check_mask, num_bits);
 776         else
 777                 compare_failed = buf_cmp(captured, in_check_value, num_bits);
 778
 779         if (compare_failed) {
 780                 char *captured_str, *in_check_value_str;
 781                 int bits = (num_bits > DEBUG_JTAG_IOZ)
 782                                 ? DEBUG_JTAG_IOZ
 783                                 : num_bits;
 784
 785                 /* NOTE:  we've lost diagnostic context here -- 'which tap' */
 786
 787                 captured_str = buf_to_str(captured, bits, 16);
 788                 in_check_value_str = buf_to_str(in_check_value, bits, 16);
 789
 790                 LOG_WARNING("Bad value '%s' captured during DR or IR scan:",
 791                                 captured_str);
 792                 LOG_WARNING(" check_value: 0x%s", in_check_value_str);
 793
 794                 free(captured_str);
 795                 free(in_check_value_str);
 796
 797                 if (in_check_mask) {
 798                         char *in_check_mask_str;
 799
 800                         in_check_mask_str = buf_to_str(in_check_mask, bits, 16);
 801                         LOG_WARNING(" check_mask: 0x%s", in_check_mask_str);
 802                         free(in_check_mask_str);
 803                 }
 804
 805                 retval = ERROR_JTAG_QUEUE_FAILED;
 806         }
 807         return retval;
 808 }
 809
 810 void jtag_check_value_mask(struct scan_field *field, uint8_t *value, uint8_t *mask)
 811 {
 812         assert(field->in_value != NULL);
 813
 814         if (value == NULL)
 815         {
 816                 /* no checking to do */
 817                 return;
 818         }
 819
 820         jtag_execute_queue_noclear();
 821
 822         int retval = jtag_check_value_inner(field->in_value, value, mask, field->num_bits);
 823         jtag_set_error(retval);
 824 }
 825
 826
 827
 828 int default_interface_jtag_execute_queue(void)
 829 {
 830         if (NULL == jtag)
 831         {
 832                 LOG_ERROR("No JTAG interface configured yet.  "
 833                         "Issue 'init' command in startup scripts "
 834                         "before communicating with targets.");
 835                 return ERROR_FAIL;
 836         }
 837
 838         return jtag->execute_queue();
 839 }
 840
 841 void jtag_execute_queue_noclear(void)
 842 {
 843         jtag_flush_queue_count++;
 844         jtag_set_error(interface_jtag_execute_queue());
 845 }
 846
 847 int jtag_get_flush_queue_count(void)
 848 {
 849         return jtag_flush_queue_count;
 850 }
 851
 852 int jtag_execute_queue(void)
 853 {
 854         jtag_execute_queue_noclear();
 855         return jtag_error_clear();
 856 }
 857
 858 static int jtag_reset_callback(enum jtag_event event, void *priv)
 859 {
 860         struct jtag_tap *tap = priv;
 861
 862         if (event == JTAG_TRST_ASSERTED)
 863         {
 864                 tap->enabled = !tap->disabled_after_reset;
 865
 866                 /* current instruction is either BYPASS or IDCODE */
 867                 buf_set_ones(tap->cur_instr, tap->ir_length);
 868                 tap->bypass = 1;
 869         }
 870
 871         return ERROR_OK;
 872 }
 873
 874 void jtag_sleep(uint32_t us)
 875 {
 876         alive_sleep(us/1000);
 877 }
 878
 879 /* Maximum number of enabled JTAG devices we expect in the scan chain,
 880  * plus one (to detect garbage at the end).  Devices that don't support
 881  * IDCODE take up fewer bits, possibly allowing a few more devices.
 882  */
 883 #define JTAG_MAX_CHAIN_SIZE 20
 884
 885 #define EXTRACT_MFG(X)  (((X) & 0xffe) >> 1)
 886 #define EXTRACT_PART(X) (((X) & 0xffff000) >> 12)
 887 #define EXTRACT_VER(X)  (((X) & 0xf0000000) >> 28)
 888
 889 /* A reserved manufacturer ID is used in END_OF_CHAIN_FLAG, so we
 890  * know that no valid TAP will have it as an IDCODE value.
 891  */
 892 #define END_OF_CHAIN_FLAG       0x000000ff
 893
 894 /* a larger IR length than we ever expect to autoprobe */
 895 #define JTAG_IRLEN_MAX          60
 896
 897 static int jtag_examine_chain_execute(uint8_t *idcode_buffer, unsigned num_idcode)
 898 {
 899         struct scan_field field = {
 900                         .num_bits = num_idcode * 32,
 901                         .out_value = idcode_buffer,
 902                         .in_value = idcode_buffer,
 903                 };
 904
 905         // initialize to the end of chain ID value
 906         for (unsigned i = 0; i < JTAG_MAX_CHAIN_SIZE; i++)
 907                 buf_set_u32(idcode_buffer, i * 32, 32, END_OF_CHAIN_FLAG);
 908
 909         jtag_add_plain_dr_scan(1, &field, TAP_DRPAUSE);
 910         jtag_add_tlr();
 911         return jtag_execute_queue();
 912 }
 913
 914 static bool jtag_examine_chain_check(uint8_t *idcodes, unsigned count)
 915 {
 916         uint8_t zero_check = 0x0;
 917         uint8_t one_check = 0xff;
 918
 919         for (unsigned i = 0; i < count * 4; i++)
 920         {
 921                 zero_check |= idcodes[i];
 922                 one_check &= idcodes[i];
 923         }
 924
 925         /* if there wasn't a single non-zero bit or if all bits were one,
 926          * the scan is not valid.  We wrote a mix of both values; either
 927          *
 928          *  - There's a hardware issue (almost certainly):
 929          *     + all-zeroes can mean a target stuck in JTAG reset
 930          *     + all-ones tends to mean no target
 931          *  - The scan chain is WAY longer than we can handle, *AND* either
 932          *     + there are several hundreds of TAPs in bypass, or
 933          *     + at least a few dozen TAPs all have an all-ones IDCODE
 934          */
 935         if (zero_check == 0x00 || one_check == 0xff)
 936         {
 937                 LOG_ERROR("JTAG scan chain interrogation failed: all %s",
 938                                 (zero_check == 0x00) ? "zeroes" : "ones");
 939                 LOG_ERROR("Check JTAG interface, timings, target power, etc.");
 940                 return false;
 941         }
 942         return true;
 943 }
 944
 945 static void jtag_examine_chain_display(enum log_levels level, const char *msg,
 946                 const char *name, uint32_t idcode)
 947 {
 948         log_printf_lf(level, __FILE__, __LINE__, __FUNCTION__,
 949                                   "JTAG tap: %s %16.16s: 0x%08x "
 950                                   "(mfg: 0x%3.3x, part: 0x%4.4x, ver: 0x%1.1x)",
 951                                   name, msg,
 952                                   (unsigned int)idcode,
 953                                   (unsigned int)EXTRACT_MFG(idcode),
 954                                   (unsigned int)EXTRACT_PART(idcode),
 955                                   (unsigned int)EXTRACT_VER(idcode));
 956 }
 957
 958 static bool jtag_idcode_is_final(uint32_t idcode)
 959 {
 960         /*
 961          * Some devices, such as AVR8, will output all 1's instead
 962          * of TDI input value at end of chain.  Allow those values
 963          * instead of failing.
 964          */
 965         return idcode == END_OF_CHAIN_FLAG || idcode == 0xFFFFFFFF;
 966 }
 967
 968 /**
 969  * This helper checks that remaining bits in the examined chain data are
 970  * all as expected, but a single JTAG device requires only 64 bits to be
 971  * read back correctly.  This can help identify and diagnose problems
 972  * with the JTAG chain earlier, gives more helpful/explicit error messages.
 973  * Returns TRUE iff garbage was found.
 974  */
 975 static bool jtag_examine_chain_end(uint8_t *idcodes, unsigned count, unsigned max)
 976 {
 977         bool triggered = false;
 978         for (; count < max - 31; count += 32)
 979         {
 980                 uint32_t idcode = buf_get_u32(idcodes, count, 32);
 981
 982                 /* do not trigger the warning if the data looks good */
 983                 if (jtag_idcode_is_final(idcode))
 984                         continue;
 985                 LOG_WARNING("Unexpected idcode after end of chain: %d 0x%08x",
 986                                         count, (unsigned int)idcode);
 987                 triggered = true;
 988         }
 989         return triggered;
 990 }
 991
 992 static bool jtag_examine_chain_match_tap(const struct jtag_tap *tap)
 993 {
 994         uint32_t idcode = tap->idcode;
 995
 996         /* ignore expected BYPASS codes; warn otherwise */
 997         if (0 == tap->expected_ids_cnt && !idcode)
 998                 return true;
 999
1000         /* optionally ignore the JTAG version field */
1001         uint32_t mask = tap->ignore_version ? ~(0xff << 24) : ~0;
1002
1003         idcode &= mask;
1004
1005         /* Loop over the expected identification codes and test for a match */
1006         unsigned ii, limit = tap->expected_ids_cnt;
1007
1008         for (ii = 0; ii < limit; ii++)
1009         {
1010                 uint32_t expected = tap->expected_ids[ii] & mask;
1011
1012                 if (idcode == expected)
1013                         return true;
1014
1015                 /* treat "-expected-id 0" as a "don't-warn" wildcard */
1016                 if (0 == tap->expected_ids[ii])
1017                         return true;
1018         }
1019
1020         /* If none of the expected ids matched, warn */
1021         jtag_examine_chain_display(LOG_LVL_WARNING, "UNEXPECTED",
1022                         tap->dotted_name, tap->idcode);
1023         for (ii = 0; ii < limit; ii++)
1024         {
1025                 char msg[32];
1026
1027                 snprintf(msg, sizeof(msg), "expected %u of %u", ii + 1, limit);
1028                 jtag_examine_chain_display(LOG_LVL_ERROR, msg,
1029                                 tap->dotted_name, tap->expected_ids[ii]);
1030         }
1031         return false;
1032 }
1033
1034 /* Try to examine chain layout according to IEEE 1149.1 §12
1035  * This is called a "blind interrogation" of the scan chain.
1036  */
1037 static int jtag_examine_chain(void)
1038 {
1039         uint8_t idcode_buffer[JTAG_MAX_CHAIN_SIZE * 4];
1040         unsigned bit_count;
1041         int retval;
1042         int tapcount = 0;
1043         bool autoprobe = false;
1044
1045         /* DR scan to collect BYPASS or IDCODE register contents.
1046          * Then make sure the scan data has both ones and zeroes.
1047          */
1048         LOG_DEBUG("DR scan interrogation for IDCODE/BYPASS");
1049         retval = jtag_examine_chain_execute(idcode_buffer, JTAG_MAX_CHAIN_SIZE);
1050         if (retval != ERROR_OK)
1051                 return retval;
1052         if (!jtag_examine_chain_check(idcode_buffer, JTAG_MAX_CHAIN_SIZE))
1053                 return ERROR_JTAG_INIT_FAILED;
1054
1055         /* point at the 1st tap */
1056         struct jtag_tap *tap = jtag_tap_next_enabled(NULL);
1057
1058         if (!tap)
1059                 autoprobe = true;
1060
1061         for (bit_count = 0;
1062                         tap && bit_count < (JTAG_MAX_CHAIN_SIZE * 32) - 31;
1063                         tap = jtag_tap_next_enabled(tap))
1064         {
1065                 uint32_t idcode = buf_get_u32(idcode_buffer, bit_count, 32);
1066
1067                 if ((idcode & 1) == 0)
1068                 {
1069                         /* Zero for LSB indicates a device in bypass */
1070                         LOG_INFO("TAP %s does not have IDCODE",
1071                                         tap->dotted_name);
1072                         idcode = 0;
1073                         tap->hasidcode = false;
1074
1075                         bit_count += 1;
1076                 }
1077                 else
1078                 {
1079                         /* Friendly devices support IDCODE */
1080                         tap->hasidcode = true;
1081                         jtag_examine_chain_display(LOG_LVL_INFO,
1082                                         "tap/device found",
1083                                         tap->dotted_name, idcode);
1084
1085                         bit_count += 32;
1086                 }
1087                 tap->idcode = idcode;
1088
1089                 /* ensure the TAP ID matches what was expected */
1090                 if (!jtag_examine_chain_match_tap(tap))
1091                         retval = ERROR_JTAG_INIT_SOFT_FAIL;
1092         }
1093
1094         /* Fail if too many TAPs were enabled for us to verify them all. */
1095         if (tap) {
1096                 LOG_ERROR("Too many TAPs enabled; '%s' ignored.",
1097                                 tap->dotted_name);
1098                 return ERROR_JTAG_INIT_FAILED;
1099         }
1100
1101         /* if autoprobing, the tap list is still empty ... populate it! */
1102         while (autoprobe && bit_count < (JTAG_MAX_CHAIN_SIZE * 32) - 31) {
1103                 uint32_t idcode;
1104                 char buf[12];
1105
1106                 /* Is there another TAP? */
1107                 idcode = buf_get_u32(idcode_buffer, bit_count, 32);
1108                 if (jtag_idcode_is_final(idcode))
1109                         break;
1110
1111                 /* Default everything in this TAP except IR length.
1112                  *
1113                  * REVISIT create a jtag_alloc(chip, tap) routine, and
1114                  * share it with jim_newtap_cmd().
1115                  */
1116                 tap = calloc(1, sizeof *tap);
1117                 if (!tap)
1118                         return ERROR_FAIL;
1119
1120                 sprintf(buf, "auto%d", tapcount++);
1121                 tap->chip = strdup(buf);
1122                 tap->tapname = strdup("tap");
1123
1124                 sprintf(buf, "%s.%s", tap->chip, tap->tapname);
1125                 tap->dotted_name = strdup(buf);
1126
1127                 /* tap->ir_length == 0 ... signifying irlen autoprobe */
1128                 tap->ir_capture_mask = 0x03;
1129                 tap->ir_capture_value = 0x01;
1130
1131                 tap->enabled = true;
1132
1133                 if ((idcode & 1) == 0) {
1134                         bit_count += 1;
1135                         tap->hasidcode = false;
1136                 } else {
1137                         bit_count += 32;
1138                         tap->hasidcode = true;
1139                         tap->idcode = idcode;
1140
1141                         tap->expected_ids_cnt = 1;
1142                         tap->expected_ids = malloc(sizeof(uint32_t));
1143                         tap->expected_ids[0] = idcode;
1144                 }
1145
1146                 LOG_WARNING("AUTO %s - use \"jtag newtap "
1147                                 "%s %s -expected-id 0x%8.8" PRIx32 " ...\"",
1148                                 tap->dotted_name, tap->chip, tap->tapname,
1149                                 tap->idcode);
1150
1151                 jtag_tap_init(tap);
1152         }
1153
1154         /* After those IDCODE or BYPASS register values should be
1155          * only the data we fed into the scan chain.
1156          */
1157         if (jtag_examine_chain_end(idcode_buffer, bit_count,
1158                         8 * sizeof(idcode_buffer))) {
1159                 LOG_ERROR("double-check your JTAG setup (interface, "
1160                                 "speed, missing TAPs, ...)");
1161                 return ERROR_JTAG_INIT_FAILED;
1162         }
1163
1164         /* Return success or, for backwards compatibility if only
1165          * some IDCODE values mismatched, a soft/continuable fault.
1166          */
1167         return retval;
1168 }
1169
1170 /*
1171  * Validate the date loaded by entry to the Capture-IR state, to help
1172  * find errors related to scan chain configuration (wrong IR lengths)
1173  * or communication.
1174  *
1175  * Entry state can be anything.  On non-error exit, all TAPs are in
1176  * bypass mode.  On error exits, the scan chain is reset.
1177  */
1178 static int jtag_validate_ircapture(void)
1179 {
1180         struct jtag_tap *tap;
1181         int total_ir_length = 0;
1182         uint8_t *ir_test = NULL;
1183         struct scan_field field;
1184         int val;
1185         int chain_pos = 0;
1186         int retval;
1187
1188         /* when autoprobing, accomodate huge IR lengths */
1189         for (tap = NULL, total_ir_length = 0;
1190                         (tap = jtag_tap_next_enabled(tap)) != NULL;
1191                         total_ir_length += tap->ir_length) {
1192                 if (tap->ir_length == 0)
1193                         total_ir_length += JTAG_IRLEN_MAX;
1194         }
1195
1196         /* increase length to add 2 bit sentinel after scan */
1197         total_ir_length += 2;
1198
1199         ir_test = malloc(DIV_ROUND_UP(total_ir_length, 8));
1200         if (ir_test == NULL)
1201                 return ERROR_FAIL;
1202
1203         /* after this scan, all TAPs will capture BYPASS instructions */
1204         buf_set_ones(ir_test, total_ir_length);
1205
1206         field.num_bits = total_ir_length;
1207         field.out_value = ir_test;
1208         field.in_value = ir_test;
1209
1210         jtag_add_plain_ir_scan(1, &field, TAP_IDLE);
1211
1212         LOG_DEBUG("IR capture validation scan");
1213         retval = jtag_execute_queue();
1214         if (retval != ERROR_OK)
1215                 goto done;
1216
1217         tap = NULL;
1218         chain_pos = 0;
1219
1220         for (;;) {
1221                 tap = jtag_tap_next_enabled(tap);
1222                 if (tap == NULL) {
1223                         break;
1224                 }
1225
1226                 /* If we're autoprobing, guess IR lengths.  They must be at
1227                  * least two bits.  Guessing will fail if (a) any TAP does
1228                  * not conform to the JTAG spec; or (b) when the upper bits
1229                  * captured from some conforming TAP are nonzero.  Or if
1230                  * (c) an IR length is longer than 32 bits -- which is only
1231                  * an implementation limit, which could someday be raised.
1232                  *
1233                  * REVISIT optimization:  if there's a *single* TAP we can
1234                  * lift restrictions (a) and (b) by scanning a recognizable
1235                  * pattern before the all-ones BYPASS.  Check for where the
1236                  * pattern starts in the result, instead of an 0...01 value.
1237                  *
1238                  * REVISIT alternative approach: escape to some tcl code
1239                  * which could provide more knowledge, based on IDCODE; and
1240                  * only guess when that has no success.
1241                  */
1242                 if (tap->ir_length == 0) {
1243                         tap->ir_length = 2;
1244                         while ((val = buf_get_u32(ir_test, chain_pos,
1245                                                 tap->ir_length + 1)) == 1
1246                                         && tap->ir_length <= 32) {
1247                                 tap->ir_length++;
1248                         }
1249                         LOG_WARNING("AUTO %s - use \"... -irlen %d\"",
1250                                         jtag_tap_name(tap), tap->ir_length);
1251                 }
1252
1253                 /* Validate the two LSBs, which must be 01 per JTAG spec.
1254                  *
1255                  * Or ... more bits could be provided by TAP declaration.
1256                  * Plus, some taps (notably in i.MX series chips) violate
1257                  * this part of the JTAG spec, so their capture mask/value
1258                  * attributes might disable this test.
1259                  */
1260                 val = buf_get_u32(ir_test, chain_pos, tap->ir_length);
1261                 if ((val & tap->ir_capture_mask) != tap->ir_capture_value) {
1262                         LOG_ERROR("%s: IR capture error; saw 0x%0*x not 0x%0*x",
1263                                         jtag_tap_name(tap),
1264                                         (tap->ir_length + 7) / tap->ir_length,
1265                                         val,
1266                                         (tap->ir_length + 7) / tap->ir_length,
1267                                         (unsigned) tap->ir_capture_value);
1268
1269                         retval = ERROR_JTAG_INIT_FAILED;
1270                         goto done;
1271                 }
1272                 LOG_DEBUG("%s: IR capture 0x%0*x", jtag_tap_name(tap),
1273                                 (tap->ir_length + 7) / tap->ir_length, val);
1274                 chain_pos += tap->ir_length;
1275         }
1276
1277         /* verify the '11' sentinel we wrote is returned at the end */
1278         val = buf_get_u32(ir_test, chain_pos, 2);
1279         if (val != 0x3)
1280         {
1281                 char *cbuf = buf_to_str(ir_test, total_ir_length, 16);
1282
1283                 LOG_ERROR("IR capture error at bit %d, saw 0x%s not 0x...3",
1284                                 chain_pos, cbuf);
1285                 free(cbuf);
1286                 retval = ERROR_JTAG_INIT_FAILED;
1287         }
1288
1289 done:
1290         free(ir_test);
1291         if (retval != ERROR_OK) {
1292                 jtag_add_tlr();
1293                 jtag_execute_queue();
1294         }
1295         return retval;
1296 }
1297
1298
1299 void jtag_tap_init(struct jtag_tap *tap)
1300 {
1301         unsigned ir_len_bits;
1302         unsigned ir_len_bytes;
1303
1304         /* if we're autoprobing, cope with potentially huge ir_length */
1305         ir_len_bits = tap->ir_length ? : JTAG_IRLEN_MAX;
1306         ir_len_bytes = DIV_ROUND_UP(ir_len_bits, 8);
1307
1308         tap->expected = calloc(1, ir_len_bytes);
1309         tap->expected_mask = calloc(1, ir_len_bytes);
1310         tap->cur_instr = malloc(ir_len_bytes);
1311
1312         /// @todo cope better with ir_length bigger than 32 bits
1313         if (ir_len_bits > 32)
1314                 ir_len_bits = 32;
1315
1316         buf_set_u32(tap->expected, 0, ir_len_bits, tap->ir_capture_value);
1317         buf_set_u32(tap->expected_mask, 0, ir_len_bits, tap->ir_capture_mask);
1318
1319         // TAP will be in bypass mode after jtag_validate_ircapture()
1320         tap->bypass = 1;
1321         buf_set_ones(tap->cur_instr, tap->ir_length);
1322
1323         // register the reset callback for the TAP
1324         jtag_register_event_callback(&jtag_reset_callback, tap);
1325
1326         LOG_DEBUG("Created Tap: %s @ abs position %d, "
1327                         "irlen %d, capture: 0x%x mask: 0x%x", tap->dotted_name,
1328                                 tap->abs_chain_position, tap->ir_length,
1329                                 (unsigned) tap->ir_capture_value,
1330                                 (unsigned) tap->ir_capture_mask);
1331         jtag_tap_add(tap);
1332 }
1333
1334 void jtag_tap_free(struct jtag_tap *tap)
1335 {
1336         jtag_unregister_event_callback(&jtag_reset_callback, tap);
1337
1338         /// @todo is anything missing? no memory leaks please
1339         free((void *)tap->expected);
1340         free((void *)tap->expected_ids);
1341         free((void *)tap->chip);
1342         free((void *)tap->tapname);
1343         free((void *)tap->dotted_name);
1344         free(tap);
1345 }
1346
1347 int jtag_interface_init(struct command_context *cmd_ctx)
1348 {
1349         if (jtag)
1350                 return ERROR_OK;
1351
1352         if (!jtag_interface)
1353         {
1354                 /* nothing was previously specified by "interface" command */
1355                 LOG_ERROR("JTAG interface has to be specified, see \"interface\" command");
1356                 return ERROR_JTAG_INVALID_INTERFACE;
1357         }
1358
1359         jtag = jtag_interface;
1360         if (jtag_interface->init() != ERROR_OK)
1361         {
1362                 jtag = NULL;
1363                 return ERROR_JTAG_INIT_FAILED;
1364         }
1365
1366         int requested_khz = jtag_get_speed_khz();
1367         int actual_khz = requested_khz;
1368         int retval = jtag_get_speed_readable(&actual_khz);
1369         if (ERROR_OK != retval)
1370                 LOG_INFO("interface specific clock speed value %d", jtag_get_speed());
1371         else if (actual_khz)
1372         {
1373                 if ((CLOCK_MODE_RCLK == clock_mode)
1374                         || ((CLOCK_MODE_KHZ == clock_mode) && !requested_khz))
1375                 {
1376                         LOG_INFO("RCLK (adaptive clock speed) not supported - fallback to %d kHz"
1377                                 , actual_khz);
1378                 }
1379                 else
1380                         LOG_INFO("clock speed %d kHz", actual_khz);
1381         }
1382         else
1383                 LOG_INFO("RCLK (adaptive clock speed)");
1384
1385         return ERROR_OK;
1386 }
1387
1388 int jtag_init_inner(struct command_context *cmd_ctx)
1389 {
1390         struct jtag_tap *tap;
1391         int retval;
1392         bool issue_setup = true;
1393
1394         LOG_DEBUG("Init JTAG chain");
1395
1396         tap = jtag_tap_next_enabled(NULL);
1397         if (tap == NULL) {
1398                 /* Once JTAG itself is properly set up, and the scan chain
1399                  * isn't absurdly large, IDCODE autoprobe should work fine.
1400                  *
1401                  * But ... IRLEN autoprobe can fail even on systems which
1402                  * are fully conformant to JTAG.  Also, JTAG setup can be
1403                  * quite finicky on some systems.
1404                  *
1405                  * REVISIT: if TAP autoprobe works OK, then in many cases
1406                  * we could escape to tcl code and set up targets based on
1407                  * the TAP's IDCODE values.
1408                  */
1409                 LOG_WARNING("There are no enabled taps.  "
1410                                 "AUTO PROBING MIGHT NOT WORK!!");
1411
1412                 /* REVISIT default clock will often be too fast ... */
1413         }
1414
1415         jtag_add_tlr();
1416         if ((retval = jtag_execute_queue()) != ERROR_OK)
1417                 return retval;
1418
1419         /* Examine DR values first.  This discovers problems which will
1420          * prevent communication ... hardware issues like TDO stuck, or
1421          * configuring the wrong number of (enabled) TAPs.
1422          */
1423         retval = jtag_examine_chain();
1424         switch (retval) {
1425         case ERROR_OK:
1426                 /* complete success */
1427                 break;
1428         case ERROR_JTAG_INIT_SOFT_FAIL:
1429                 /* For backward compatibility reasons, try coping with
1430                  * configuration errors involving only ID mismatches.
1431                  * We might be able to talk to the devices.
1432                  */
1433                 LOG_ERROR("Trying to use configured scan chain anyway...");
1434                 issue_setup = false;
1435                 break;
1436         default:
1437                 /* some hard error; already issued diagnostics */
1438                 return retval;
1439         }
1440
1441         /* Now look at IR values.  Problems here will prevent real
1442          * communication.  They mostly mean that the IR length is
1443          * wrong ... or that the IR capture value is wrong.  (The
1444          * latter is uncommon, but easily worked around:  provide
1445          * ircapture/irmask values during TAP setup.)
1446          */
1447         retval = jtag_validate_ircapture();
1448         if (retval != ERROR_OK)
1449                 return retval;
1450
1451         if (issue_setup)
1452                 jtag_notify_event(JTAG_TAP_EVENT_SETUP);
1453         else
1454                 LOG_WARNING("Bypassing JTAG setup events due to errors");
1455
1456
1457         return ERROR_OK;
1458 }
1459
1460 int jtag_interface_quit(void)
1461 {
1462         if (!jtag || !jtag->quit)
1463                 return ERROR_OK;
1464
1465         // close the JTAG interface
1466         int result = jtag->quit();
1467         if (ERROR_OK != result)
1468                 LOG_ERROR("failed: %d", result);
1469
1470         return ERROR_OK;
1471 }
1472
1473
1474 int jtag_init_reset(struct command_context *cmd_ctx)
1475 {
1476         int retval;
1477
1478         if ((retval = jtag_interface_init(cmd_ctx)) != ERROR_OK)
1479                 return retval;
1480
1481         LOG_DEBUG("Initializing with hard TRST+SRST reset");
1482
1483         /*
1484          * This procedure is used by default when OpenOCD triggers a reset.
1485          * It's now done through an overridable Tcl "init_reset" wrapper.
1486          *
1487          * This started out as a more powerful "get JTAG working" reset than
1488          * jtag_init_inner(), applying TRST because some chips won't activate
1489          * JTAG without a TRST cycle (presumed to be async, though some of
1490          * those chips synchronize JTAG activation using TCK).
1491          *
1492          * But some chips only activate JTAG as part of an SRST cycle; SRST
1493          * got mixed in.  So it became a hard reset routine, which got used
1494          * in more places, and which coped with JTAG reset being forced as
1495          * part of SRST (srst_pulls_trst).
1496          *
1497          * And even more corner cases started to surface:  TRST and/or SRST
1498          * assertion timings matter; some chips need other JTAG operations;
1499          * TRST/SRST sequences can need to be different from these, etc.
1500          *
1501          * Systems should override that wrapper to support system-specific
1502          * requirements that this not-fully-generic code doesn't handle.
1503          *
1504          * REVISIT once Tcl code can read the reset_config modes, this won't
1505          * need to be a C routine at all...
1506          */
1507         jtag_add_reset(1, 0); /* TAP_RESET, using TMS+TCK or TRST */
1508         if (jtag_reset_config & RESET_HAS_SRST)
1509         {
1510                 jtag_add_reset(1, 1);
1511                 if ((jtag_reset_config & RESET_SRST_PULLS_TRST) == 0)
1512                         jtag_add_reset(0, 1);
1513         }
1514         jtag_add_reset(0, 0);
1515         if ((retval = jtag_execute_queue()) != ERROR_OK)
1516                 return retval;
1517
1518         /* Check that we can communication on the JTAG chain + eventually we want to
1519          * be able to perform enumeration only after OpenOCD has started
1520          * telnet and GDB server
1521          *
1522          * That would allow users to more easily perform any magic they need to before
1523          * reset happens.
1524          */
1525         return jtag_init_inner(cmd_ctx);
1526 }
1527
1528 int jtag_init(struct command_context *cmd_ctx)
1529 {
1530         int retval;
1531
1532         if ((retval = jtag_interface_init(cmd_ctx)) != ERROR_OK)
1533                 return retval;
1534
1535         /* guard against oddball hardware: force resets to be inactive */
1536         jtag_add_reset(0, 0);
1537         if ((retval = jtag_execute_queue()) != ERROR_OK)
1538                 return retval;
1539
1540         if (Jim_Eval_Named(cmd_ctx->interp, "jtag_init", __FILE__, __LINE__) != JIM_OK)
1541                 return ERROR_FAIL;
1542
1543         return ERROR_OK;
1544 }
1545
1546 unsigned jtag_get_speed_khz(void)
1547 {
1548         return speed_khz;
1549 }
1550
1551 static int jtag_khz_to_speed(unsigned khz, int* speed)
1552 {
1553         LOG_DEBUG("convert khz to interface specific speed value");
1554         speed_khz = khz;
1555         if (jtag != NULL)
1556         {
1557                 LOG_DEBUG("have interface set up");
1558                 int speed_div1;
1559                 int retval = jtag->khz(jtag_get_speed_khz(), &speed_div1);
1560                 if (ERROR_OK != retval)
1561                 {
1562                         return retval;
1563                 }
1564                 *speed = speed_div1;
1565         }
1566         return ERROR_OK;
1567 }
1568
1569 static int jtag_rclk_to_speed(unsigned fallback_speed_khz, int* speed)
1570 {
1571         int retval = jtag_khz_to_speed(0, speed);
1572         if ((ERROR_OK != retval) && fallback_speed_khz)
1573         {
1574                 LOG_DEBUG("trying fallback speed...");
1575                 retval = jtag_khz_to_speed(fallback_speed_khz, speed);
1576         }
1577         return retval;
1578 }
1579
1580 static int jtag_set_speed(int speed)
1581 {
1582         jtag_speed = speed;
1583         /* this command can be called during CONFIG,
1584          * in which case jtag isn't initialized */
1585         return jtag ? jtag->speed(speed) : ERROR_OK;
1586 }
1587
1588 int jtag_config_khz(unsigned khz)
1589 {
1590         LOG_DEBUG("handle jtag khz");
1591         clock_mode = CLOCK_MODE_KHZ;
1592         int speed = 0;
1593         int retval = jtag_khz_to_speed(khz, &speed);
1594         return (ERROR_OK != retval) ? retval : jtag_set_speed(speed);
1595 }
1596
1597 int jtag_config_rclk(unsigned fallback_speed_khz)
1598 {
1599         LOG_DEBUG("handle jtag rclk");
1600         clock_mode = CLOCK_MODE_RCLK;
1601         rclk_fallback_speed_khz = fallback_speed_khz;
1602         int speed = 0;
1603         int retval = jtag_rclk_to_speed(fallback_speed_khz, &speed);
1604         return (ERROR_OK != retval) ? retval : jtag_set_speed(speed);
1605 }
1606
1607 int jtag_get_speed(void)
1608 {
1609         int speed;
1610         switch(clock_mode)
1611         {
1612                 case CLOCK_MODE_SPEED:
1613                         speed = jtag_speed;
1614                         break;
1615                 case CLOCK_MODE_KHZ:
1616                         jtag_khz_to_speed(jtag_get_speed_khz(), &speed);
1617                         break;
1618                 case CLOCK_MODE_RCLK:
1619                         jtag_rclk_to_speed(rclk_fallback_speed_khz, &speed);
1620                         break;
1621                 default:
1622                         LOG_ERROR("BUG: unknown jtag clock mode");
1623                         speed = 0;
1624                         break;
1625         }
1626         return speed;
1627 }
1628
1629 int jtag_get_speed_readable(int *khz)
1630 {
1631         return jtag ? jtag->speed_div(jtag_get_speed(), khz) : ERROR_OK;
1632 }
1633
1634 void jtag_set_verify(bool enable)
1635 {
1636         jtag_verify = enable;
1637 }
1638
1639 bool jtag_will_verify()
1640 {
1641         return jtag_verify;
1642 }
1643
1644 void jtag_set_verify_capture_ir(bool enable)
1645 {
1646         jtag_verify_capture_ir = enable;
1647 }
1648
1649 bool jtag_will_verify_capture_ir()
1650 {
1651         return jtag_verify_capture_ir;
1652 }
1653
1654 int jtag_power_dropout(int *dropout)
1655 {
1656         if (jtag == NULL)
1657         {
1658                 /* TODO: as the jtag interface is not valid all
1659                  * we can do at the moment is exit OpenOCD */
1660                 LOG_ERROR("No Valid JTAG Interface Configured.");
1661                 exit(-1);
1662         }
1663         return jtag->power_dropout(dropout);
1664 }
1665
1666 int jtag_srst_asserted(int *srst_asserted)
1667 {
1668         return jtag->srst_asserted(srst_asserted);
1669 }
1670
1671 enum reset_types jtag_get_reset_config(void)
1672 {
1673         return jtag_reset_config;
1674 }
1675 void jtag_set_reset_config(enum reset_types type)
1676 {
1677         jtag_reset_config = type;
1678 }
1679
1680 int jtag_get_trst(void)
1681 {
1682         return jtag_trst;
1683 }
1684 int jtag_get_srst(void)
1685 {
1686         return jtag_srst;
1687 }
1688
1689 void jtag_set_nsrst_delay(unsigned delay)
1690 {
1691         jtag_nsrst_delay = delay;
1692 }
1693 unsigned jtag_get_nsrst_delay(void)
1694 {
1695         return jtag_nsrst_delay;
1696 }
1697 void jtag_set_ntrst_delay(unsigned delay)
1698 {
1699         jtag_ntrst_delay = delay;
1700 }
1701 unsigned jtag_get_ntrst_delay(void)
1702 {
1703         return jtag_ntrst_delay;
1704 }
1705
1706
1707 void jtag_set_nsrst_assert_width(unsigned delay)
1708 {
1709         jtag_nsrst_assert_width = delay;
1710 }
1711 unsigned jtag_get_nsrst_assert_width(void)
1712 {
1713         return jtag_nsrst_assert_width;
1714 }
1715 void jtag_set_ntrst_assert_width(unsigned delay)
1716 {
1717         jtag_ntrst_assert_width = delay;
1718 }
1719 unsigned jtag_get_ntrst_assert_width(void)
1720 {
1721         return jtag_ntrst_assert_width;
1722 }