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