git.sur5r.net Git - 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  * The value is set and cleared, but never read by normal application code.
  56  *
  57  * This value is returned (and cleared) by 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 tap_state_t cmd_queue_cur_state = TAP_RESET;
  90
  91 static bool jtag_verify_capture_ir = true;
  92 static int jtag_verify = 1;
  93
  94 /* how long the OpenOCD should wait before attempting JTAG communication after reset lines deasserted (in ms) */
  95 static int adapter_nsrst_delay = 0; /* default to no nSRST delay */
  96 static int jtag_ntrst_delay = 0; /* default to no nTRST delay */
  97 static int adapter_nsrst_assert_width = 0; /* width of assertion */
  98 static int jtag_ntrst_assert_width = 0; /* width of assertion */
  99
 100 /**
 101  * Contains a single callback along with a pointer that will be passed
 102  * when an event occurs.
 103  */
 104 struct jtag_event_callback {
 105         /// a event callback
 106         jtag_event_handler_t callback;
 107         /// the private data to pass to the callback
 108         void* priv;
 109         /// the next callback
 110         struct jtag_event_callback* next;
 111 };
 112
 113 /* callbacks to inform high-level handlers about JTAG state changes */
 114 static struct jtag_event_callback *jtag_event_callbacks;
 115
 116 /* speed in kHz*/
 117 static int speed_khz = 0;
 118 /* speed to fallback to when RCLK is requested but not supported */
 119 static int rclk_fallback_speed_khz = 0;
 120 static enum {CLOCK_MODE_SPEED, CLOCK_MODE_KHZ, CLOCK_MODE_RCLK} clock_mode;
 121 static int jtag_speed = 0;
 122
 123 static struct jtag_interface *jtag = NULL;
 124
 125 /* configuration */
 126 struct jtag_interface *jtag_interface = NULL;
 127
 128 void jtag_set_error(int error)
 129 {
 130         if ((error == ERROR_OK) || (jtag_error != ERROR_OK))
 131                 return;
 132         jtag_error = error;
 133 }
 134
 135 int jtag_error_clear(void)
 136 {
 137         int temp = jtag_error;
 138         jtag_error = ERROR_OK;
 139         return temp;
 140 }
 141
 142 /************/
 143
 144 static bool jtag_poll = 1;
 145
 146 bool is_jtag_poll_safe(void)
 147 {
 148         /* Polling can be disabled explicitly with set_enabled(false).
 149          * It is also implicitly disabled while TRST is active and
 150          * while SRST is gating the JTAG clock.
 151          */
 152         if (!jtag_poll || jtag_trst != 0)
 153                 return false;
 154         return jtag_srst == 0 || (jtag_reset_config & RESET_SRST_NO_GATING);
 155 }
 156
 157 bool jtag_poll_get_enabled(void)
 158 {
 159         return jtag_poll;
 160 }
 161
 162 void jtag_poll_set_enabled(bool value)
 163 {
 164         jtag_poll = value;
 165 }
 166
 167 /************/
 168
 169 struct jtag_tap *jtag_all_taps(void)
 170 {
 171         return __jtag_all_taps;
 172 };
 173
 174 unsigned jtag_tap_count(void)
 175 {
 176         return jtag_num_taps;
 177 }
 178
 179 unsigned jtag_tap_count_enabled(void)
 180 {
 181         struct jtag_tap *t = jtag_all_taps();
 182         unsigned n = 0;
 183         while (t)
 184         {
 185                 if (t->enabled)
 186                         n++;
 187                 t = t->next_tap;
 188         }
 189         return n;
 190 }
 191
 192 /// Append a new TAP to the chain of all taps.
 193 void jtag_tap_add(struct jtag_tap *t)
 194 {
 195         t->abs_chain_position = jtag_num_taps++;
 196
 197         struct jtag_tap **tap = &__jtag_all_taps;
 198         while (*tap != NULL)
 199                 tap = &(*tap)->next_tap;
 200         *tap = t;
 201 }
 202
 203 /* returns a pointer to the n-th device in the scan chain */
 204 static inline struct jtag_tap *jtag_tap_by_position(unsigned n)
 205 {
 206         struct jtag_tap *t = jtag_all_taps();
 207
 208         while (t && n-- > 0)
 209                 t = t->next_tap;
 210
 211         return t;
 212 }
 213
 214 struct jtag_tap *jtag_tap_by_string(const char *s)
 215 {
 216         /* try by name first */
 217         struct jtag_tap *t = jtag_all_taps();
 218
 219         while (t)
 220         {
 221                 if (0 == strcmp(t->dotted_name, s))
 222                         return t;
 223                 t = t->next_tap;
 224         }
 225
 226         /* no tap found by name, so try to parse the name as a number */
 227         unsigned n;
 228         if (parse_uint(s, &n) != ERROR_OK)
 229                 return NULL;
 230
 231         /* FIXME remove this numeric fallback code late June 2010, along
 232          * with all info in the User's Guide that TAPs have numeric IDs.
 233          * Also update "scan_chain" output to not display the numbers.
 234          */
 235         t = jtag_tap_by_position(n);
 236         if (t)
 237                 LOG_WARNING("Specify TAP '%s' by name, not number %u",
 238                         t->dotted_name, n);
 239
 240         return t;
 241 }
 242
 243 struct jtag_tap* jtag_tap_next_enabled(struct jtag_tap* p)
 244 {
 245         p = p ? p->next_tap : jtag_all_taps();
 246         while (p)
 247         {
 248                 if (p->enabled)
 249                         return p;
 250                 p = p->next_tap;
 251         }
 252         return NULL;
 253 }
 254
 255 const char *jtag_tap_name(const struct jtag_tap *tap)
 256 {
 257         return (tap == NULL) ? "(unknown)" : tap->dotted_name;
 258 }
 259
 260
 261 int jtag_register_event_callback(jtag_event_handler_t callback, void *priv)
 262 {
 263         struct jtag_event_callback **callbacks_p = &jtag_event_callbacks;
 264
 265         if (callback == NULL)
 266         {
 267                 return ERROR_INVALID_ARGUMENTS;
 268         }
 269
 270         if (*callbacks_p)
 271         {
 272                 while ((*callbacks_p)->next)
 273                         callbacks_p = &((*callbacks_p)->next);
 274                 callbacks_p = &((*callbacks_p)->next);
 275         }
 276
 277         (*callbacks_p) = malloc(sizeof(struct jtag_event_callback));
 278         (*callbacks_p)->callback = callback;
 279         (*callbacks_p)->priv = priv;
 280         (*callbacks_p)->next = NULL;
 281
 282         return ERROR_OK;
 283 }
 284
 285 int jtag_unregister_event_callback(jtag_event_handler_t callback, void *priv)
 286 {
 287         struct jtag_event_callback **callbacks_p;
 288         struct jtag_event_callback **next;
 289
 290         if (callback == NULL)
 291         {
 292                 return ERROR_INVALID_ARGUMENTS;
 293         }
 294
 295         for (callbacks_p = &jtag_event_callbacks;
 296                         *callbacks_p != NULL;
 297                         callbacks_p = next)
 298         {
 299                 next = &((*callbacks_p)->next);
 300
 301                 if ((*callbacks_p)->priv != priv)
 302                         continue;
 303
 304                 if ((*callbacks_p)->callback == callback)
 305                 {
 306                         free(*callbacks_p);
 307                         *callbacks_p = *next;
 308                 }
 309         }
 310
 311         return ERROR_OK;
 312 }
 313
 314 int jtag_call_event_callbacks(enum jtag_event event)
 315 {
 316         struct jtag_event_callback *callback = jtag_event_callbacks;
 317
 318         LOG_DEBUG("jtag event: %s", jtag_event_strings[event]);
 319
 320         while (callback)
 321         {
 322                 struct jtag_event_callback *next;
 323
 324                 /* callback may remove itself */
 325                 next = callback->next;
 326                 callback->callback(event, callback->priv);
 327                 callback = next;
 328         }
 329
 330         return ERROR_OK;
 331 }
 332
 333 static void jtag_checks(void)
 334 {
 335         assert(jtag_trst == 0);
 336 }
 337
 338 static void jtag_prelude(tap_state_t state)
 339 {
 340         jtag_checks();
 341
 342         assert(state != TAP_INVALID);
 343
 344         cmd_queue_cur_state = state;
 345 }
 346
 347 void jtag_alloc_in_value32(struct scan_field *field)
 348 {
 349         interface_jtag_alloc_in_value32(field);
 350 }
 351
 352 void jtag_add_ir_scan_noverify(struct jtag_tap *active, const struct scan_field *in_fields,
 353                 tap_state_t state)
 354 {
 355         jtag_prelude(state);
 356
 357         int retval = interface_jtag_add_ir_scan(active, in_fields, state);
 358         jtag_set_error(retval);
 359 }
 360
 361 static void jtag_add_ir_scan_noverify_callback(struct jtag_tap *active, int dummy, const struct scan_field *in_fields,
 362                 tap_state_t state)
 363 {
 364         jtag_add_ir_scan_noverify(active, in_fields, state);
 365 }
 366
 367 void jtag_add_ir_scan(struct jtag_tap *active, struct scan_field *in_fields, tap_state_t state)
 368 {
 369         assert(state != TAP_RESET);
 370
 371         if (jtag_verify && jtag_verify_capture_ir)
 372         {
 373                 /* 8 x 32 bit id's is enough for all invocations */
 374
 375                 /* if we are to run a verification of the ir scan, we need to get the input back.
 376                  * We may have to allocate space if the caller didn't ask for the input back.
 377                  */
 378                 in_fields->check_value = active->expected;
 379                 in_fields->check_mask = active->expected_mask;
 380                 jtag_add_scan_check(active, jtag_add_ir_scan_noverify_callback, 1, in_fields, state);
 381         } else
 382         {
 383                 jtag_add_ir_scan_noverify(active, in_fields, state);
 384         }
 385 }
 386
 387 void jtag_add_plain_ir_scan(int num_bits, const uint8_t *out_bits, uint8_t *in_bits,
 388                 tap_state_t state)
 389 {
 390         assert(out_bits != NULL);
 391         assert(state != TAP_RESET);
 392
 393         jtag_prelude(state);
 394
 395         int retval = interface_jtag_add_plain_ir_scan(
 396                         num_bits, out_bits, in_bits, state);
 397         jtag_set_error(retval);
 398 }
 399
 400 static int jtag_check_value_inner(uint8_t *captured, uint8_t *in_check_value,
 401                 uint8_t *in_check_mask, int num_bits);
 402
 403 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)
 404 {
 405         return jtag_check_value_inner((uint8_t *)data0, (uint8_t *)data1, (uint8_t *)data2, (int)data3);
 406 }
 407
 408 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),
 409                 int in_num_fields, struct scan_field *in_fields, tap_state_t state)
 410 {
 411         for (int i = 0; i < in_num_fields; i++)
 412         {
 413                 struct scan_field *field = &in_fields[i];
 414                 field->allocated = 0;
 415                 field->modified = 0;
 416                 if (field->check_value || field->in_value)
 417                         continue;
 418                 interface_jtag_add_scan_check_alloc(field);
 419                 field->modified = 1;
 420         }
 421
 422         jtag_add_scan(active, in_num_fields, in_fields, state);
 423
 424         for (int i = 0; i < in_num_fields; i++)
 425         {
 426                 if ((in_fields[i].check_value != NULL) && (in_fields[i].in_value != NULL))
 427                 {
 428                         /* this is synchronous for a minidriver */
 429                         jtag_add_callback4(jtag_check_value_mask_callback, (jtag_callback_data_t)in_fields[i].in_value,
 430                                 (jtag_callback_data_t)in_fields[i].check_value,
 431                                 (jtag_callback_data_t)in_fields[i].check_mask,
 432                                 (jtag_callback_data_t)in_fields[i].num_bits);
 433                 }
 434                 if (in_fields[i].allocated)
 435                 {
 436                         free(in_fields[i].in_value);
 437                 }
 438                 if (in_fields[i].modified)
 439                 {
 440                         in_fields[i].in_value = NULL;
 441                 }
 442         }
 443 }
 444
 445 void jtag_add_dr_scan_check(struct jtag_tap *active, int in_num_fields, struct scan_field *in_fields, tap_state_t state)
 446 {
 447         if (jtag_verify)
 448         {
 449                 jtag_add_scan_check(active, jtag_add_dr_scan, in_num_fields, in_fields, state);
 450         } else
 451         {
 452                 jtag_add_dr_scan(active, in_num_fields, in_fields, state);
 453         }
 454 }
 455
 456
 457 void jtag_add_dr_scan(struct jtag_tap *active, int in_num_fields, const struct scan_field *in_fields,
 458                 tap_state_t state)
 459 {
 460         assert(state != TAP_RESET);
 461
 462         jtag_prelude(state);
 463
 464         int retval;
 465         retval = interface_jtag_add_dr_scan(active, in_num_fields, in_fields, state);
 466         jtag_set_error(retval);
 467 }
 468
 469 void jtag_add_plain_dr_scan(int num_bits, const uint8_t *out_bits, uint8_t *in_bits,
 470                 tap_state_t state)
 471 {
 472         assert(out_bits != NULL);
 473         assert(state != TAP_RESET);
 474
 475         jtag_prelude(state);
 476
 477         int retval;
 478         retval = interface_jtag_add_plain_dr_scan(num_bits, out_bits, in_bits, state);
 479         jtag_set_error(retval);
 480 }
 481
 482 void jtag_add_tlr(void)
 483 {
 484         jtag_prelude(TAP_RESET);
 485         jtag_set_error(interface_jtag_add_tlr());
 486
 487         /* NOTE: order here matches TRST path in jtag_add_reset() */
 488         jtag_call_event_callbacks(JTAG_TRST_ASSERTED);
 489         jtag_notify_event(JTAG_TRST_ASSERTED);
 490 }
 491
 492 /**
 493  * If supported by the underlying adapter, this clocks a raw bit sequence
 494  * onto TMS for switching betwen JTAG and SWD modes.
 495  *
 496  * DO NOT use this to bypass the integrity checks and logging provided
 497  * by the jtag_add_pathmove() and jtag_add_statemove() calls.
 498  *
 499  * @param nbits How many bits to clock out.
 500  * @param seq The bit sequence.  The LSB is bit 0 of seq[0].
 501  * @param state The JTAG tap state to record on completion.  Use
 502  *      TAP_INVALID to represent being in in SWD mode.
 503  *
 504  * @todo Update naming conventions to stop assuming everything is JTAG.
 505  */
 506 int jtag_add_tms_seq(unsigned nbits, const uint8_t *seq, enum tap_state state)
 507 {
 508         int retval;
 509
 510         if (!(jtag->supported & DEBUG_CAP_TMS_SEQ))
 511                 return ERROR_JTAG_NOT_IMPLEMENTED;
 512
 513         jtag_checks();
 514         cmd_queue_cur_state = state;
 515
 516         retval = interface_add_tms_seq(nbits, seq, state);
 517         jtag_set_error(retval);
 518         return retval;
 519 }
 520
 521 void jtag_add_pathmove(int num_states, const tap_state_t *path)
 522 {
 523         tap_state_t cur_state = cmd_queue_cur_state;
 524
 525         /* the last state has to be a stable state */
 526         if (!tap_is_state_stable(path[num_states - 1]))
 527         {
 528                 LOG_ERROR("BUG: TAP path doesn't finish in a stable state");
 529                 jtag_set_error(ERROR_JTAG_NOT_STABLE_STATE);
 530                 return;
 531         }
 532
 533         for (int i = 0; i < num_states; i++)
 534         {
 535                 if (path[i] == TAP_RESET)
 536                 {
 537                         LOG_ERROR("BUG: TAP_RESET is not a valid state for pathmove sequences");
 538                         jtag_set_error(ERROR_JTAG_STATE_INVALID);
 539                         return;
 540                 }
 541
 542                 if (tap_state_transition(cur_state, true)  != path[i]
 543                   && tap_state_transition(cur_state, false) != path[i])
 544                 {
 545                         LOG_ERROR("BUG: %s -> %s isn't a valid TAP transition",
 546                                         tap_state_name(cur_state), tap_state_name(path[i]));
 547                         jtag_set_error(ERROR_JTAG_TRANSITION_INVALID);
 548                         return;
 549                 }
 550                 cur_state = path[i];
 551         }
 552
 553         jtag_checks();
 554
 555         jtag_set_error(interface_jtag_add_pathmove(num_states, path));
 556         cmd_queue_cur_state = path[num_states - 1];
 557 }
 558
 559 int jtag_add_statemove(tap_state_t goal_state)
 560 {
 561         tap_state_t cur_state = cmd_queue_cur_state;
 562
 563         if (goal_state != cur_state)
 564         {
 565                 LOG_DEBUG("cur_state=%s goal_state=%s",
 566                         tap_state_name(cur_state),
 567                         tap_state_name(goal_state));
 568         }
 569
 570         /* If goal is RESET, be paranoid and force that that transition
 571          * (e.g. five TCK cycles, TMS high).  Else trust "cur_state".
 572          */
 573         if (goal_state == TAP_RESET)
 574                 jtag_add_tlr();
 575         else if (goal_state == cur_state)
 576                 /* nothing to do */ ;
 577
 578         else if (tap_is_state_stable(cur_state) && tap_is_state_stable(goal_state))
 579         {
 580                 unsigned tms_bits  = tap_get_tms_path(cur_state, goal_state);
 581                 unsigned tms_count = tap_get_tms_path_len(cur_state, goal_state);
 582                 tap_state_t moves[8];
 583                 assert(tms_count < ARRAY_SIZE(moves));
 584
 585                 for (unsigned i = 0; i < tms_count; i++, tms_bits >>= 1)
 586                 {
 587                         bool bit = tms_bits & 1;
 588
 589                         cur_state = tap_state_transition(cur_state, bit);
 590                         moves[i] = cur_state;
 591                 }
 592
 593                 jtag_add_pathmove(tms_count, moves);
 594         }
 595         else if (tap_state_transition(cur_state, true)  == goal_state
 596                 ||   tap_state_transition(cur_state, false) == goal_state)
 597         {
 598                 jtag_add_pathmove(1, &goal_state);
 599         }
 600
 601         else
 602                 return ERROR_FAIL;
 603
 604         return ERROR_OK;
 605 }
 606
 607 void jtag_add_runtest(int num_cycles, tap_state_t state)
 608 {
 609         jtag_prelude(state);
 610         jtag_set_error(interface_jtag_add_runtest(num_cycles, state));
 611 }
 612
 613
 614 void jtag_add_clocks(int num_cycles)
 615 {
 616         if (!tap_is_state_stable(cmd_queue_cur_state))
 617         {
 618                  LOG_ERROR("jtag_add_clocks() called with TAP in unstable state \"%s\"",
 619                                  tap_state_name(cmd_queue_cur_state));
 620                  jtag_set_error(ERROR_JTAG_NOT_STABLE_STATE);
 621                  return;
 622         }
 623
 624         if (num_cycles > 0)
 625         {
 626                 jtag_checks();
 627                 jtag_set_error(interface_jtag_add_clocks(num_cycles));
 628         }
 629 }
 630
 631 void jtag_add_reset(int req_tlr_or_trst, int req_srst)
 632 {
 633         int trst_with_tlr = 0;
 634         int new_srst = 0;
 635         int new_trst = 0;
 636
 637         /* Without SRST, we must use target-specific JTAG operations
 638          * on each target; callers should not be requesting SRST when
 639          * that signal doesn't exist.
 640          *
 641          * RESET_SRST_PULLS_TRST is a board or chip level quirk, which
 642          * can kick in even if the JTAG adapter can't drive TRST.
 643          */
 644         if (req_srst) {
 645                 if (!(jtag_reset_config & RESET_HAS_SRST)) {
 646                         LOG_ERROR("BUG: can't assert SRST");
 647                         jtag_set_error(ERROR_FAIL);
 648                         return;
 649                 }
 650                 if ((jtag_reset_config & RESET_SRST_PULLS_TRST) != 0
 651                                 && !req_tlr_or_trst) {
 652                         LOG_ERROR("BUG: can't assert only SRST");
 653                         jtag_set_error(ERROR_FAIL);
 654                         return;
 655                 }
 656                 new_srst = 1;
 657         }
 658
 659         /* JTAG reset (entry to TAP_RESET state) can always be achieved
 660          * using TCK and TMS; that may go through a TAP_{IR,DR}UPDATE
 661          * state first.  TRST accelerates it, and bypasses those states.
 662          *
 663          * RESET_TRST_PULLS_SRST is a board or chip level quirk, which
 664          * can kick in even if the JTAG adapter can't drive SRST.
 665          */
 666         if (req_tlr_or_trst) {
 667                 if (!(jtag_reset_config & RESET_HAS_TRST))
 668                         trst_with_tlr = 1;
 669                 else if ((jtag_reset_config & RESET_TRST_PULLS_SRST) != 0
 670                                 && !req_srst)
 671                         trst_with_tlr = 1;
 672                 else
 673                         new_trst = 1;
 674         }
 675
 676         /* Maybe change TRST and/or SRST signal state */
 677         if (jtag_srst != new_srst || jtag_trst != new_trst) {
 678                 int retval;
 679
 680                 retval = interface_jtag_add_reset(new_trst, new_srst);
 681                 if (retval != ERROR_OK)
 682                         jtag_set_error(retval);
 683                 else
 684                         retval = jtag_execute_queue();
 685
 686                 if (retval != ERROR_OK) {
 687                         LOG_ERROR("TRST/SRST error %d", retval);
 688                         return;
 689                 }
 690         }
 691
 692         /* SRST resets everything hooked up to that signal */
 693         if (jtag_srst != new_srst) {
 694                 jtag_srst = new_srst;
 695                 if (jtag_srst)
 696                 {
 697                         LOG_DEBUG("SRST line asserted");
 698                         if (adapter_nsrst_assert_width)
 699                                 jtag_add_sleep(adapter_nsrst_assert_width * 1000);
 700                 }
 701                 else {
 702                         LOG_DEBUG("SRST line released");
 703                         if (adapter_nsrst_delay)
 704                                 jtag_add_sleep(adapter_nsrst_delay * 1000);
 705                 }
 706         }
 707
 708         /* Maybe enter the JTAG TAP_RESET state ...
 709          *  - using only TMS, TCK, and the JTAG state machine
 710          *  - or else more directly, using TRST
 711          *
 712          * TAP_RESET should be invisible to non-debug parts of the system.
 713          */
 714         if (trst_with_tlr) {
 715                 LOG_DEBUG("JTAG reset with TLR instead of TRST");
 716                 jtag_add_tlr();
 717
 718         } else if (jtag_trst != new_trst) {
 719                 jtag_trst = new_trst;
 720                 if (jtag_trst) {
 721                         LOG_DEBUG("TRST line asserted");
 722                         tap_set_state(TAP_RESET);
 723                         if (jtag_ntrst_assert_width)
 724                                 jtag_add_sleep(jtag_ntrst_assert_width * 1000);
 725                 } else {
 726                         LOG_DEBUG("TRST line released");
 727                         if (jtag_ntrst_delay)
 728                                 jtag_add_sleep(jtag_ntrst_delay * 1000);
 729
 730                         /* We just asserted nTRST, so we're now in TAP_RESET.
 731                          * Inform possible listeners about this, now that
 732                          * JTAG instructions and data can be shifted.  This
 733                          * sequence must match jtag_add_tlr().
 734                          */
 735                         jtag_call_event_callbacks(JTAG_TRST_ASSERTED);
 736                         jtag_notify_event(JTAG_TRST_ASSERTED);
 737                 }
 738         }
 739 }
 740
 741 void jtag_add_sleep(uint32_t us)
 742 {
 743         /// @todo Here, keep_alive() appears to be a layering violation!!!
 744         keep_alive();
 745         jtag_set_error(interface_jtag_add_sleep(us));
 746 }
 747
 748 static int jtag_check_value_inner(uint8_t *captured, uint8_t *in_check_value,
 749                 uint8_t *in_check_mask, int num_bits)
 750 {
 751         int retval = ERROR_OK;
 752         int compare_failed;
 753
 754         if (in_check_mask)
 755                 compare_failed = buf_cmp_mask(captured, in_check_value, in_check_mask, num_bits);
 756         else
 757                 compare_failed = buf_cmp(captured, in_check_value, num_bits);
 758
 759         if (compare_failed) {
 760                 char *captured_str, *in_check_value_str;
 761                 int bits = (num_bits > DEBUG_JTAG_IOZ)
 762                                 ? DEBUG_JTAG_IOZ
 763                                 : num_bits;
 764
 765                 /* NOTE:  we've lost diagnostic context here -- 'which tap' */
 766
 767                 captured_str = buf_to_str(captured, bits, 16);
 768                 in_check_value_str = buf_to_str(in_check_value, bits, 16);
 769
 770                 LOG_WARNING("Bad value '%s' captured during DR or IR scan:",
 771                                 captured_str);
 772                 LOG_WARNING(" check_value: 0x%s", in_check_value_str);
 773
 774                 free(captured_str);
 775                 free(in_check_value_str);
 776
 777                 if (in_check_mask) {
 778                         char *in_check_mask_str;
 779
 780                         in_check_mask_str = buf_to_str(in_check_mask, bits, 16);
 781                         LOG_WARNING(" check_mask: 0x%s", in_check_mask_str);
 782                         free(in_check_mask_str);
 783                 }
 784
 785                 retval = ERROR_JTAG_QUEUE_FAILED;
 786         }
 787         return retval;
 788 }
 789
 790 void jtag_check_value_mask(struct scan_field *field, uint8_t *value, uint8_t *mask)
 791 {
 792         assert(field->in_value != NULL);
 793
 794         if (value == NULL)
 795         {
 796                 /* no checking to do */
 797                 return;
 798         }
 799
 800         jtag_execute_queue_noclear();
 801
 802         int retval = jtag_check_value_inner(field->in_value, value, mask, field->num_bits);
 803         jtag_set_error(retval);
 804 }
 805
 806
 807
 808 int default_interface_jtag_execute_queue(void)
 809 {
 810         if (NULL == jtag)
 811         {
 812                 LOG_ERROR("No JTAG interface configured yet.  "
 813                         "Issue 'init' command in startup scripts "
 814                         "before communicating with targets.");
 815                 return ERROR_FAIL;
 816         }
 817
 818         return jtag->execute_queue();
 819 }
 820
 821 void jtag_execute_queue_noclear(void)
 822 {
 823         jtag_flush_queue_count++;
 824         jtag_set_error(interface_jtag_execute_queue());
 825 }
 826
 827 int jtag_get_flush_queue_count(void)
 828 {
 829         return jtag_flush_queue_count;
 830 }
 831
 832 int jtag_execute_queue(void)
 833 {
 834         jtag_execute_queue_noclear();
 835         return jtag_error_clear();
 836 }
 837
 838 static int jtag_reset_callback(enum jtag_event event, void *priv)
 839 {
 840         struct jtag_tap *tap = priv;
 841
 842         if (event == JTAG_TRST_ASSERTED)
 843         {
 844                 tap->enabled = !tap->disabled_after_reset;
 845
 846                 /* current instruction is either BYPASS or IDCODE */
 847                 buf_set_ones(tap->cur_instr, tap->ir_length);
 848                 tap->bypass = 1;
 849         }
 850
 851         return ERROR_OK;
 852 }
 853
 854 void jtag_sleep(uint32_t us)
 855 {
 856         alive_sleep(us/1000);
 857 }
 858
 859 /* Maximum number of enabled JTAG devices we expect in the scan chain,
 860  * plus one (to detect garbage at the end).  Devices that don't support
 861  * IDCODE take up fewer bits, possibly allowing a few more devices.
 862  */
 863 #define JTAG_MAX_CHAIN_SIZE 20
 864
 865 #define EXTRACT_MFG(X)  (((X) & 0xffe) >> 1)
 866 #define EXTRACT_PART(X) (((X) & 0xffff000) >> 12)
 867 #define EXTRACT_VER(X)  (((X) & 0xf0000000) >> 28)
 868
 869 /* A reserved manufacturer ID is used in END_OF_CHAIN_FLAG, so we
 870  * know that no valid TAP will have it as an IDCODE value.
 871  */
 872 #define END_OF_CHAIN_FLAG       0x000000ff
 873
 874 /* a larger IR length than we ever expect to autoprobe */
 875 #define JTAG_IRLEN_MAX          60
 876
 877 static int jtag_examine_chain_execute(uint8_t *idcode_buffer, unsigned num_idcode)
 878 {
 879         struct scan_field field = {
 880                         .num_bits = num_idcode * 32,
 881                         .out_value = idcode_buffer,
 882                         .in_value = idcode_buffer,
 883                 };
 884
 885         // initialize to the end of chain ID value
 886         for (unsigned i = 0; i < JTAG_MAX_CHAIN_SIZE; i++)
 887                 buf_set_u32(idcode_buffer, i * 32, 32, END_OF_CHAIN_FLAG);
 888
 889         jtag_add_plain_dr_scan(field.num_bits, field.out_value, field.in_value, TAP_DRPAUSE);
 890         jtag_add_tlr();
 891         return jtag_execute_queue();
 892 }
 893
 894 static bool jtag_examine_chain_check(uint8_t *idcodes, unsigned count)
 895 {
 896         uint8_t zero_check = 0x0;
 897         uint8_t one_check = 0xff;
 898
 899         for (unsigned i = 0; i < count * 4; i++)
 900         {
 901                 zero_check |= idcodes[i];
 902                 one_check &= idcodes[i];
 903         }
 904
 905         /* if there wasn't a single non-zero bit or if all bits were one,
 906          * the scan is not valid.  We wrote a mix of both values; either
 907          *
 908          *  - There's a hardware issue (almost certainly):
 909          *     + all-zeroes can mean a target stuck in JTAG reset
 910          *     + all-ones tends to mean no target
 911          *  - The scan chain is WAY longer than we can handle, *AND* either
 912          *     + there are several hundreds of TAPs in bypass, or
 913          *     + at least a few dozen TAPs all have an all-ones IDCODE
 914          */
 915         if (zero_check == 0x00 || one_check == 0xff)
 916         {
 917                 LOG_ERROR("JTAG scan chain interrogation failed: all %s",
 918                                 (zero_check == 0x00) ? "zeroes" : "ones");
 919                 LOG_ERROR("Check JTAG interface, timings, target power, etc.");
 920                 return false;
 921         }
 922         return true;
 923 }
 924
 925 static void jtag_examine_chain_display(enum log_levels level, const char *msg,
 926                 const char *name, uint32_t idcode)
 927 {
 928         log_printf_lf(level, __FILE__, __LINE__, __FUNCTION__,
 929                                   "JTAG tap: %s %16.16s: 0x%08x "
 930                                   "(mfg: 0x%3.3x, part: 0x%4.4x, ver: 0x%1.1x)",
 931                                   name, msg,
 932                                   (unsigned int)idcode,
 933                                   (unsigned int)EXTRACT_MFG(idcode),
 934                                   (unsigned int)EXTRACT_PART(idcode),
 935                                   (unsigned int)EXTRACT_VER(idcode));
 936 }
 937
 938 static bool jtag_idcode_is_final(uint32_t idcode)
 939 {
 940         /*
 941          * Some devices, such as AVR8, will output all 1's instead
 942          * of TDI input value at end of chain.  Allow those values
 943          * instead of failing.
 944          */
 945         return idcode == END_OF_CHAIN_FLAG || idcode == 0xFFFFFFFF;
 946 }
 947
 948 /**
 949  * This helper checks that remaining bits in the examined chain data are
 950  * all as expected, but a single JTAG device requires only 64 bits to be
 951  * read back correctly.  This can help identify and diagnose problems
 952  * with the JTAG chain earlier, gives more helpful/explicit error messages.
 953  * Returns TRUE iff garbage was found.
 954  */
 955 static bool jtag_examine_chain_end(uint8_t *idcodes, unsigned count, unsigned max)
 956 {
 957         bool triggered = false;
 958         for (; count < max - 31; count += 32)
 959         {
 960                 uint32_t idcode = buf_get_u32(idcodes, count, 32);
 961
 962                 /* do not trigger the warning if the data looks good */
 963                 if (jtag_idcode_is_final(idcode))
 964                         continue;
 965                 LOG_WARNING("Unexpected idcode after end of chain: %d 0x%08x",
 966                                         count, (unsigned int)idcode);
 967                 triggered = true;
 968         }
 969         return triggered;
 970 }
 971
 972 static bool jtag_examine_chain_match_tap(const struct jtag_tap *tap)
 973 {
 974         uint32_t idcode = tap->idcode;
 975
 976         /* ignore expected BYPASS codes; warn otherwise */
 977         if (0 == tap->expected_ids_cnt && !idcode)
 978                 return true;
 979
 980         /* optionally ignore the JTAG version field */
 981         uint32_t mask = tap->ignore_version ? ~(0xff << 24) : ~0;
 982
 983         idcode &= mask;
 984
 985         /* Loop over the expected identification codes and test for a match */
 986         unsigned ii, limit = tap->expected_ids_cnt;
 987
 988         for (ii = 0; ii < limit; ii++)
 989         {
 990                 uint32_t expected = tap->expected_ids[ii] & mask;
 991
 992                 if (idcode == expected)
 993                         return true;
 994
 995                 /* treat "-expected-id 0" as a "don't-warn" wildcard */
 996                 if (0 == tap->expected_ids[ii])
 997                         return true;
 998         }
 999
1000         /* If none of the expected ids matched, warn */
1001         jtag_examine_chain_display(LOG_LVL_WARNING, "UNEXPECTED",
1002                         tap->dotted_name, tap->idcode);
1003         for (ii = 0; ii < limit; ii++)
1004         {
1005                 char msg[32];
1006
1007                 snprintf(msg, sizeof(msg), "expected %u of %u", ii + 1, limit);
1008                 jtag_examine_chain_display(LOG_LVL_ERROR, msg,
1009                                 tap->dotted_name, tap->expected_ids[ii]);
1010         }
1011         return false;
1012 }
1013
1014 /* Try to examine chain layout according to IEEE 1149.1 §12
1015  * This is called a "blind interrogation" of the scan chain.
1016  */
1017 static int jtag_examine_chain(void)
1018 {
1019         uint8_t idcode_buffer[JTAG_MAX_CHAIN_SIZE * 4];
1020         unsigned bit_count;
1021         int retval;
1022         int tapcount = 0;
1023         bool autoprobe = false;
1024
1025         /* DR scan to collect BYPASS or IDCODE register contents.
1026          * Then make sure the scan data has both ones and zeroes.
1027          */
1028         LOG_DEBUG("DR scan interrogation for IDCODE/BYPASS");
1029         retval = jtag_examine_chain_execute(idcode_buffer, JTAG_MAX_CHAIN_SIZE);
1030         if (retval != ERROR_OK)
1031                 return retval;
1032         if (!jtag_examine_chain_check(idcode_buffer, JTAG_MAX_CHAIN_SIZE))
1033                 return ERROR_JTAG_INIT_FAILED;
1034
1035         /* point at the 1st tap */
1036         struct jtag_tap *tap = jtag_tap_next_enabled(NULL);
1037
1038         if (!tap)
1039                 autoprobe = true;
1040
1041         for (bit_count = 0;
1042                         tap && bit_count < (JTAG_MAX_CHAIN_SIZE * 32) - 31;
1043                         tap = jtag_tap_next_enabled(tap))
1044         {
1045                 uint32_t idcode = buf_get_u32(idcode_buffer, bit_count, 32);
1046
1047                 if ((idcode & 1) == 0)
1048                 {
1049                         /* Zero for LSB indicates a device in bypass */
1050                         LOG_INFO("TAP %s does not have IDCODE",
1051                                         tap->dotted_name);
1052                         idcode = 0;
1053                         tap->hasidcode = false;
1054
1055                         bit_count += 1;
1056                 }
1057                 else
1058                 {
1059                         /* Friendly devices support IDCODE */
1060                         tap->hasidcode = true;
1061                         jtag_examine_chain_display(LOG_LVL_INFO,
1062                                         "tap/device found",
1063                                         tap->dotted_name, idcode);
1064
1065                         bit_count += 32;
1066                 }
1067                 tap->idcode = idcode;
1068
1069                 /* ensure the TAP ID matches what was expected */
1070                 if (!jtag_examine_chain_match_tap(tap))
1071                         retval = ERROR_JTAG_INIT_SOFT_FAIL;
1072         }
1073
1074         /* Fail if too many TAPs were enabled for us to verify them all. */
1075         if (tap) {
1076                 LOG_ERROR("Too many TAPs enabled; '%s' ignored.",
1077                                 tap->dotted_name);
1078                 return ERROR_JTAG_INIT_FAILED;
1079         }
1080
1081         /* if autoprobing, the tap list is still empty ... populate it! */
1082         while (autoprobe && bit_count < (JTAG_MAX_CHAIN_SIZE * 32) - 31) {
1083                 uint32_t idcode;
1084                 char buf[12];
1085
1086                 /* Is there another TAP? */
1087                 idcode = buf_get_u32(idcode_buffer, bit_count, 32);
1088                 if (jtag_idcode_is_final(idcode))
1089                         break;
1090
1091                 /* Default everything in this TAP except IR length.
1092                  *
1093                  * REVISIT create a jtag_alloc(chip, tap) routine, and
1094                  * share it with jim_newtap_cmd().
1095                  */
1096                 tap = calloc(1, sizeof *tap);
1097                 if (!tap)
1098                         return ERROR_FAIL;
1099
1100                 sprintf(buf, "auto%d", tapcount++);
1101                 tap->chip = strdup(buf);
1102                 tap->tapname = strdup("tap");
1103
1104                 sprintf(buf, "%s.%s", tap->chip, tap->tapname);
1105                 tap->dotted_name = strdup(buf);
1106
1107                 /* tap->ir_length == 0 ... signifying irlen autoprobe */
1108                 tap->ir_capture_mask = 0x03;
1109                 tap->ir_capture_value = 0x01;
1110
1111                 tap->enabled = true;
1112
1113                 if ((idcode & 1) == 0) {
1114                         bit_count += 1;
1115                         tap->hasidcode = false;
1116                 } else {
1117                         bit_count += 32;
1118                         tap->hasidcode = true;
1119                         tap->idcode = idcode;
1120
1121                         tap->expected_ids_cnt = 1;
1122                         tap->expected_ids = malloc(sizeof(uint32_t));
1123                         tap->expected_ids[0] = idcode;
1124                 }
1125
1126                 LOG_WARNING("AUTO %s - use \"jtag newtap "
1127                                 "%s %s -expected-id 0x%8.8" PRIx32 " ...\"",
1128                                 tap->dotted_name, tap->chip, tap->tapname,
1129                                 tap->idcode);
1130
1131                 jtag_tap_init(tap);
1132         }
1133
1134         /* After those IDCODE or BYPASS register values should be
1135          * only the data we fed into the scan chain.
1136          */
1137         if (jtag_examine_chain_end(idcode_buffer, bit_count,
1138                         8 * sizeof(idcode_buffer))) {
1139                 LOG_ERROR("double-check your JTAG setup (interface, "
1140                                 "speed, missing TAPs, ...)");
1141                 return ERROR_JTAG_INIT_FAILED;
1142         }
1143
1144         /* Return success or, for backwards compatibility if only
1145          * some IDCODE values mismatched, a soft/continuable fault.
1146          */
1147         return retval;
1148 }
1149
1150 /*
1151  * Validate the date loaded by entry to the Capture-IR state, to help
1152  * find errors related to scan chain configuration (wrong IR lengths)
1153  * or communication.
1154  *
1155  * Entry state can be anything.  On non-error exit, all TAPs are in
1156  * bypass mode.  On error exits, the scan chain is reset.
1157  */
1158 static int jtag_validate_ircapture(void)
1159 {
1160         struct jtag_tap *tap;
1161         int total_ir_length = 0;
1162         uint8_t *ir_test = NULL;
1163         struct scan_field field;
1164         int val;
1165         int chain_pos = 0;
1166         int retval;
1167
1168         /* when autoprobing, accomodate huge IR lengths */
1169         for (tap = NULL, total_ir_length = 0;
1170                         (tap = jtag_tap_next_enabled(tap)) != NULL;
1171                         total_ir_length += tap->ir_length) {
1172                 if (tap->ir_length == 0)
1173                         total_ir_length += JTAG_IRLEN_MAX;
1174         }
1175
1176         /* increase length to add 2 bit sentinel after scan */
1177         total_ir_length += 2;
1178
1179         ir_test = malloc(DIV_ROUND_UP(total_ir_length, 8));
1180         if (ir_test == NULL)
1181                 return ERROR_FAIL;
1182
1183         /* after this scan, all TAPs will capture BYPASS instructions */
1184         buf_set_ones(ir_test, total_ir_length);
1185
1186         field.num_bits = total_ir_length;
1187         field.out_value = ir_test;
1188         field.in_value = ir_test;
1189
1190         jtag_add_plain_ir_scan(field.num_bits, field.out_value, field.in_value, TAP_IDLE);
1191
1192         LOG_DEBUG("IR capture validation scan");
1193         retval = jtag_execute_queue();
1194         if (retval != ERROR_OK)
1195                 goto done;
1196
1197         tap = NULL;
1198         chain_pos = 0;
1199
1200         for (;;) {
1201                 tap = jtag_tap_next_enabled(tap);
1202                 if (tap == NULL) {
1203                         break;
1204                 }
1205
1206                 /* If we're autoprobing, guess IR lengths.  They must be at
1207                  * least two bits.  Guessing will fail if (a) any TAP does
1208                  * not conform to the JTAG spec; or (b) when the upper bits
1209                  * captured from some conforming TAP are nonzero.  Or if
1210                  * (c) an IR length is longer than 32 bits -- which is only
1211                  * an implementation limit, which could someday be raised.
1212                  *
1213                  * REVISIT optimization:  if there's a *single* TAP we can
1214                  * lift restrictions (a) and (b) by scanning a recognizable
1215                  * pattern before the all-ones BYPASS.  Check for where the
1216                  * pattern starts in the result, instead of an 0...01 value.
1217                  *
1218                  * REVISIT alternative approach: escape to some tcl code
1219                  * which could provide more knowledge, based on IDCODE; and
1220                  * only guess when that has no success.
1221                  */
1222                 if (tap->ir_length == 0) {
1223                         tap->ir_length = 2;
1224                         while ((val = buf_get_u32(ir_test, chain_pos,
1225                                                 tap->ir_length + 1)) == 1
1226                                         && tap->ir_length <= 32) {
1227                                 tap->ir_length++;
1228                         }
1229                         LOG_WARNING("AUTO %s - use \"... -irlen %d\"",
1230                                         jtag_tap_name(tap), tap->ir_length);
1231                 }
1232
1233                 /* Validate the two LSBs, which must be 01 per JTAG spec.
1234                  *
1235                  * Or ... more bits could be provided by TAP declaration.
1236                  * Plus, some taps (notably in i.MX series chips) violate
1237                  * this part of the JTAG spec, so their capture mask/value
1238                  * attributes might disable this test.
1239                  */
1240                 val = buf_get_u32(ir_test, chain_pos, tap->ir_length);
1241                 if ((val & tap->ir_capture_mask) != tap->ir_capture_value) {
1242                         LOG_ERROR("%s: IR capture error; saw 0x%0*x not 0x%0*x",
1243                                         jtag_tap_name(tap),
1244                                         (tap->ir_length + 7) / tap->ir_length,
1245                                         val,
1246                                         (tap->ir_length + 7) / tap->ir_length,
1247                                         (unsigned) tap->ir_capture_value);
1248
1249                         retval = ERROR_JTAG_INIT_FAILED;
1250                         goto done;
1251                 }
1252                 LOG_DEBUG("%s: IR capture 0x%0*x", jtag_tap_name(tap),
1253                                 (tap->ir_length + 7) / tap->ir_length, val);
1254                 chain_pos += tap->ir_length;
1255         }
1256
1257         /* verify the '11' sentinel we wrote is returned at the end */
1258         val = buf_get_u32(ir_test, chain_pos, 2);
1259         if (val != 0x3)
1260         {
1261                 char *cbuf = buf_to_str(ir_test, total_ir_length, 16);
1262
1263                 LOG_ERROR("IR capture error at bit %d, saw 0x%s not 0x...3",
1264                                 chain_pos, cbuf);
1265                 free(cbuf);
1266                 retval = ERROR_JTAG_INIT_FAILED;
1267         }
1268
1269 done:
1270         free(ir_test);
1271         if (retval != ERROR_OK) {
1272                 jtag_add_tlr();
1273                 jtag_execute_queue();
1274         }
1275         return retval;
1276 }
1277
1278
1279 void jtag_tap_init(struct jtag_tap *tap)
1280 {
1281         unsigned ir_len_bits;
1282         unsigned ir_len_bytes;
1283
1284         /* if we're autoprobing, cope with potentially huge ir_length */
1285         ir_len_bits = tap->ir_length ? : JTAG_IRLEN_MAX;
1286         ir_len_bytes = DIV_ROUND_UP(ir_len_bits, 8);
1287
1288         tap->expected = calloc(1, ir_len_bytes);
1289         tap->expected_mask = calloc(1, ir_len_bytes);
1290         tap->cur_instr = malloc(ir_len_bytes);
1291
1292         /// @todo cope better with ir_length bigger than 32 bits
1293         if (ir_len_bits > 32)
1294                 ir_len_bits = 32;
1295
1296         buf_set_u32(tap->expected, 0, ir_len_bits, tap->ir_capture_value);
1297         buf_set_u32(tap->expected_mask, 0, ir_len_bits, tap->ir_capture_mask);
1298
1299         // TAP will be in bypass mode after jtag_validate_ircapture()
1300         tap->bypass = 1;
1301         buf_set_ones(tap->cur_instr, tap->ir_length);
1302
1303         // register the reset callback for the TAP
1304         jtag_register_event_callback(&jtag_reset_callback, tap);
1305
1306         LOG_DEBUG("Created Tap: %s @ abs position %d, "
1307                         "irlen %d, capture: 0x%x mask: 0x%x", tap->dotted_name,
1308                                 tap->abs_chain_position, tap->ir_length,
1309                                 (unsigned) tap->ir_capture_value,
1310                                 (unsigned) tap->ir_capture_mask);
1311         jtag_tap_add(tap);
1312 }
1313
1314 void jtag_tap_free(struct jtag_tap *tap)
1315 {
1316         jtag_unregister_event_callback(&jtag_reset_callback, tap);
1317
1318         /// @todo is anything missing? no memory leaks please
1319         free((void *)tap->expected);
1320         free((void *)tap->expected_ids);
1321         free((void *)tap->chip);
1322         free((void *)tap->tapname);
1323         free((void *)tap->dotted_name);
1324         free(tap);
1325 }
1326
1327 /**
1328  * Do low-level setup like initializing registers, output signals,
1329  * and clocking.
1330  */
1331 int adapter_init(struct command_context *cmd_ctx)
1332 {
1333         if (jtag)
1334                 return ERROR_OK;
1335
1336         if (!jtag_interface)
1337         {
1338                 /* nothing was previously specified by "interface" command */
1339                 LOG_ERROR("Debug Adapter has to be specified, "
1340                         "see \"interface\" command");
1341                 return ERROR_JTAG_INVALID_INTERFACE;
1342         }
1343
1344         jtag = jtag_interface;
1345         if (jtag_interface->init() != ERROR_OK)
1346         {
1347                 jtag = NULL;
1348                 return ERROR_JTAG_INIT_FAILED;
1349         }
1350
1351         int requested_khz = jtag_get_speed_khz();
1352         int actual_khz = requested_khz;
1353         int retval = jtag_get_speed_readable(&actual_khz);
1354         if (ERROR_OK != retval)
1355                 LOG_INFO("adapter-specific clock speed value %d", jtag_get_speed());
1356         else if (actual_khz)
1357         {
1358                 /* Adaptive clocking -- JTAG-specific */
1359                 if ((CLOCK_MODE_RCLK == clock_mode)
1360                         || ((CLOCK_MODE_KHZ == clock_mode) && !requested_khz))
1361                 {
1362                         LOG_INFO("RCLK (adaptive clock speed) not supported - fallback to %d kHz"
1363                                 , actual_khz);
1364                 }
1365                 else
1366                         LOG_INFO("clock speed %d kHz", actual_khz);
1367         }
1368         else
1369                 LOG_INFO("RCLK (adaptive clock speed)");
1370
1371         return ERROR_OK;
1372 }
1373
1374 int jtag_init_inner(struct command_context *cmd_ctx)
1375 {
1376         struct jtag_tap *tap;
1377         int retval;
1378         bool issue_setup = true;
1379
1380         LOG_DEBUG("Init JTAG chain");
1381
1382         tap = jtag_tap_next_enabled(NULL);
1383         if (tap == NULL) {
1384                 /* Once JTAG itself is properly set up, and the scan chain
1385                  * isn't absurdly large, IDCODE autoprobe should work fine.
1386                  *
1387                  * But ... IRLEN autoprobe can fail even on systems which
1388                  * are fully conformant to JTAG.  Also, JTAG setup can be
1389                  * quite finicky on some systems.
1390                  *
1391                  * REVISIT: if TAP autoprobe works OK, then in many cases
1392                  * we could escape to tcl code and set up targets based on
1393                  * the TAP's IDCODE values.
1394                  */
1395                 LOG_WARNING("There are no enabled taps.  "
1396                                 "AUTO PROBING MIGHT NOT WORK!!");
1397
1398                 /* REVISIT default clock will often be too fast ... */
1399         }
1400
1401         jtag_add_tlr();
1402         if ((retval = jtag_execute_queue()) != ERROR_OK)
1403                 return retval;
1404
1405         /* Examine DR values first.  This discovers problems which will
1406          * prevent communication ... hardware issues like TDO stuck, or
1407          * configuring the wrong number of (enabled) TAPs.
1408          */
1409         retval = jtag_examine_chain();
1410         switch (retval) {
1411         case ERROR_OK:
1412                 /* complete success */
1413                 break;
1414         case ERROR_JTAG_INIT_SOFT_FAIL:
1415                 /* For backward compatibility reasons, try coping with
1416                  * configuration errors involving only ID mismatches.
1417                  * We might be able to talk to the devices.
1418                  */
1419                 LOG_ERROR("Trying to use configured scan chain anyway...");
1420                 issue_setup = false;
1421                 break;
1422         default:
1423                 /* some hard error; already issued diagnostics */
1424                 return retval;
1425         }
1426
1427         /* Now look at IR values.  Problems here will prevent real
1428          * communication.  They mostly mean that the IR length is
1429          * wrong ... or that the IR capture value is wrong.  (The
1430          * latter is uncommon, but easily worked around:  provide
1431          * ircapture/irmask values during TAP setup.)
1432          */
1433         retval = jtag_validate_ircapture();
1434         if (retval != ERROR_OK)
1435                 return retval;
1436
1437         if (issue_setup)
1438                 jtag_notify_event(JTAG_TAP_EVENT_SETUP);
1439         else
1440                 LOG_WARNING("Bypassing JTAG setup events due to errors");
1441
1442
1443         return ERROR_OK;
1444 }
1445
1446 int adapter_quit(void)
1447 {
1448         if (!jtag || !jtag->quit)
1449                 return ERROR_OK;
1450
1451         // close the JTAG interface
1452         int result = jtag->quit();
1453         if (ERROR_OK != result)
1454                 LOG_ERROR("failed: %d", result);
1455
1456         return ERROR_OK;
1457 }
1458
1459
1460 int jtag_init_reset(struct command_context *cmd_ctx)
1461 {
1462         int retval;
1463
1464         if ((retval = adapter_init(cmd_ctx)) != ERROR_OK)
1465                 return retval;
1466
1467         LOG_DEBUG("Initializing with hard TRST+SRST reset");
1468
1469         /*
1470          * This procedure is used by default when OpenOCD triggers a reset.
1471          * It's now done through an overridable Tcl "init_reset" wrapper.
1472          *
1473          * This started out as a more powerful "get JTAG working" reset than
1474          * jtag_init_inner(), applying TRST because some chips won't activate
1475          * JTAG without a TRST cycle (presumed to be async, though some of
1476          * those chips synchronize JTAG activation using TCK).
1477          *
1478          * But some chips only activate JTAG as part of an SRST cycle; SRST
1479          * got mixed in.  So it became a hard reset routine, which got used
1480          * in more places, and which coped with JTAG reset being forced as
1481          * part of SRST (srst_pulls_trst).
1482          *
1483          * And even more corner cases started to surface:  TRST and/or SRST
1484          * assertion timings matter; some chips need other JTAG operations;
1485          * TRST/SRST sequences can need to be different from these, etc.
1486          *
1487          * Systems should override that wrapper to support system-specific
1488          * requirements that this not-fully-generic code doesn't handle.
1489          *
1490          * REVISIT once Tcl code can read the reset_config modes, this won't
1491          * need to be a C routine at all...
1492          */
1493         jtag_add_reset(1, 0); /* TAP_RESET, using TMS+TCK or TRST */
1494         if (jtag_reset_config & RESET_HAS_SRST)
1495         {
1496                 jtag_add_reset(1, 1);
1497                 if ((jtag_reset_config & RESET_SRST_PULLS_TRST) == 0)
1498                         jtag_add_reset(0, 1);
1499         }
1500         jtag_add_reset(0, 0);
1501         if ((retval = jtag_execute_queue()) != ERROR_OK)
1502                 return retval;
1503
1504         /* Check that we can communication on the JTAG chain + eventually we want to
1505          * be able to perform enumeration only after OpenOCD has started
1506          * telnet and GDB server
1507          *
1508          * That would allow users to more easily perform any magic they need to before
1509          * reset happens.
1510          */
1511         return jtag_init_inner(cmd_ctx);
1512 }
1513
1514 int jtag_init(struct command_context *cmd_ctx)
1515 {
1516         int retval;
1517
1518         if ((retval = adapter_init(cmd_ctx)) != ERROR_OK)
1519                 return retval;
1520
1521         /* guard against oddball hardware: force resets to be inactive */
1522         jtag_add_reset(0, 0);
1523         if ((retval = jtag_execute_queue()) != ERROR_OK)
1524                 return retval;
1525
1526         if (Jim_Eval_Named(cmd_ctx->interp, "jtag_init", __FILE__, __LINE__) != JIM_OK)
1527                 return ERROR_FAIL;
1528
1529         return ERROR_OK;
1530 }
1531
1532 unsigned jtag_get_speed_khz(void)
1533 {
1534         return speed_khz;
1535 }
1536
1537 static int adapter_khz_to_speed(unsigned khz, int* speed)
1538 {
1539         LOG_DEBUG("convert khz to interface specific speed value");
1540         speed_khz = khz;
1541         if (jtag != NULL)
1542         {
1543                 LOG_DEBUG("have interface set up");
1544                 int speed_div1;
1545                 int retval = jtag->khz(jtag_get_speed_khz(), &speed_div1);
1546                 if (ERROR_OK != retval)
1547                 {
1548                         return retval;
1549                 }
1550                 *speed = speed_div1;
1551         }
1552         return ERROR_OK;
1553 }
1554
1555 static int jtag_rclk_to_speed(unsigned fallback_speed_khz, int* speed)
1556 {
1557         int retval = adapter_khz_to_speed(0, speed);
1558         if ((ERROR_OK != retval) && fallback_speed_khz)
1559         {
1560                 LOG_DEBUG("trying fallback speed...");
1561                 retval = adapter_khz_to_speed(fallback_speed_khz, speed);
1562         }
1563         return retval;
1564 }
1565
1566 static int jtag_set_speed(int speed)
1567 {
1568         jtag_speed = speed;
1569         /* this command can be called during CONFIG,
1570          * in which case jtag isn't initialized */
1571         return jtag ? jtag->speed(speed) : ERROR_OK;
1572 }
1573
1574 int jtag_config_khz(unsigned khz)
1575 {
1576         LOG_DEBUG("handle jtag khz");
1577         clock_mode = CLOCK_MODE_KHZ;
1578         int speed = 0;
1579         int retval = adapter_khz_to_speed(khz, &speed);
1580         return (ERROR_OK != retval) ? retval : jtag_set_speed(speed);
1581 }
1582
1583 int jtag_config_rclk(unsigned fallback_speed_khz)
1584 {
1585         LOG_DEBUG("handle jtag rclk");
1586         clock_mode = CLOCK_MODE_RCLK;
1587         rclk_fallback_speed_khz = fallback_speed_khz;
1588         int speed = 0;
1589         int retval = jtag_rclk_to_speed(fallback_speed_khz, &speed);
1590         return (ERROR_OK != retval) ? retval : jtag_set_speed(speed);
1591 }
1592
1593 int jtag_get_speed(void)
1594 {
1595         int speed;
1596         switch(clock_mode)
1597         {
1598                 case CLOCK_MODE_SPEED:
1599                         speed = jtag_speed;
1600                         break;
1601                 case CLOCK_MODE_KHZ:
1602                         adapter_khz_to_speed(jtag_get_speed_khz(), &speed);
1603                         break;
1604                 case CLOCK_MODE_RCLK:
1605                         jtag_rclk_to_speed(rclk_fallback_speed_khz, &speed);
1606                         break;
1607                 default:
1608                         LOG_ERROR("BUG: unknown jtag clock mode");
1609                         speed = 0;
1610                         break;
1611         }
1612         return speed;
1613 }
1614
1615 int jtag_get_speed_readable(int *khz)
1616 {
1617         return jtag ? jtag->speed_div(jtag_get_speed(), khz) : ERROR_OK;
1618 }
1619
1620 void jtag_set_verify(bool enable)
1621 {
1622         jtag_verify = enable;
1623 }
1624
1625 bool jtag_will_verify()
1626 {
1627         return jtag_verify;
1628 }
1629
1630 void jtag_set_verify_capture_ir(bool enable)
1631 {
1632         jtag_verify_capture_ir = enable;
1633 }
1634
1635 bool jtag_will_verify_capture_ir()
1636 {
1637         return jtag_verify_capture_ir;
1638 }
1639
1640 int jtag_power_dropout(int *dropout)
1641 {
1642         if (jtag == NULL)
1643         {
1644                 /* TODO: as the jtag interface is not valid all
1645                  * we can do at the moment is exit OpenOCD */
1646                 LOG_ERROR("No Valid JTAG Interface Configured.");
1647                 exit(-1);
1648         }
1649         return jtag->power_dropout(dropout);
1650 }
1651
1652 int jtag_srst_asserted(int *srst_asserted)
1653 {
1654         return jtag->srst_asserted(srst_asserted);
1655 }
1656
1657 enum reset_types jtag_get_reset_config(void)
1658 {
1659         return jtag_reset_config;
1660 }
1661 void jtag_set_reset_config(enum reset_types type)
1662 {
1663         jtag_reset_config = type;
1664 }
1665
1666 int jtag_get_trst(void)
1667 {
1668         return jtag_trst;
1669 }
1670 int jtag_get_srst(void)
1671 {
1672         return jtag_srst;
1673 }
1674
1675 void jtag_set_nsrst_delay(unsigned delay)
1676 {
1677         adapter_nsrst_delay = delay;
1678 }
1679 unsigned jtag_get_nsrst_delay(void)
1680 {
1681         return adapter_nsrst_delay;
1682 }
1683 void jtag_set_ntrst_delay(unsigned delay)
1684 {
1685         jtag_ntrst_delay = delay;
1686 }
1687 unsigned jtag_get_ntrst_delay(void)
1688 {
1689         return jtag_ntrst_delay;
1690 }
1691
1692
1693 void jtag_set_nsrst_assert_width(unsigned delay)
1694 {
1695         adapter_nsrst_assert_width = delay;
1696 }
1697 unsigned jtag_get_nsrst_assert_width(void)
1698 {
1699         return adapter_nsrst_assert_width;
1700 }
1701 void jtag_set_ntrst_assert_width(unsigned delay)
1702 {
1703         jtag_ntrst_assert_width = delay;
1704 }
1705 unsigned jtag_get_ntrst_assert_width(void)
1706 {
1707         return jtag_ntrst_assert_width;
1708 }