1 /***************************************************************************
2 * Copyright (C) 2009 Zachary T Welch *
3 * zw@superlucidity.net *
5 * Copyright (C) 2007,2008,2009 Øyvind Harboe *
6 * oyvind.harboe@zylin.com *
8 * Copyright (C) 2009 SoftPLC Corporation *
12 * Copyright (C) 2005 by Dominic Rath *
13 * Dominic.Rath@gmx.de *
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. *
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. *
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 ***************************************************************************/
35 #include "interface.h"
36 #include <transport/transport.h>
42 /* SVF and XSVF are higher level JTAG command sets (for boundary scan) */
44 #include "xsvf/xsvf.h"
46 /// The number of JTAG queue flushes (for profiling and debugging purposes).
47 static int jtag_flush_queue_count;
49 // Sleep this # of ms after flushing the queue
50 static int jtag_flush_queue_sleep = 0;
52 static void jtag_add_scan_check(struct jtag_tap *active,
53 void (*jtag_add_scan)(struct jtag_tap *active, int in_num_fields, const struct scan_field *in_fields, tap_state_t state),
54 int in_num_fields, struct scan_field *in_fields, tap_state_t state);
57 * The jtag_error variable is set when an error occurs while executing
58 * the queue. Application code may set this using jtag_set_error(),
59 * when an error occurs during processing that should be reported during
60 * jtag_execute_queue().
62 * The value is set and cleared, but never read by normal application code.
64 * This value is returned (and cleared) by jtag_execute_queue().
66 static int jtag_error = ERROR_OK;
68 static const char *jtag_event_strings[] =
70 [JTAG_TRST_ASSERTED] = "TAP reset",
71 [JTAG_TAP_EVENT_SETUP] = "TAP setup",
72 [JTAG_TAP_EVENT_ENABLE] = "TAP enabled",
73 [JTAG_TAP_EVENT_DISABLE] = "TAP disabled",
77 * JTAG adapters must initialize with TRST and SRST de-asserted
78 * (they're negative logic, so that means *high*). But some
79 * hardware doesn't necessarily work that way ... so set things
80 * up so that jtag_init() always forces that state.
82 static int jtag_trst = -1;
83 static int jtag_srst = -1;
86 * List all TAPs that have been created.
88 static struct jtag_tap *__jtag_all_taps = NULL;
90 * The number of TAPs in the __jtag_all_taps list, used to track the
91 * assigned chain position to new TAPs
93 static unsigned jtag_num_taps = 0;
95 static enum reset_types jtag_reset_config = RESET_NONE;
96 tap_state_t cmd_queue_cur_state = TAP_RESET;
98 static bool jtag_verify_capture_ir = true;
99 static int jtag_verify = 1;
101 /* how long the OpenOCD should wait before attempting JTAG communication after reset lines deasserted (in ms) */
102 static int adapter_nsrst_delay = 0; /* default to no nSRST delay */
103 static int jtag_ntrst_delay = 0; /* default to no nTRST delay */
104 static int adapter_nsrst_assert_width = 0; /* width of assertion */
105 static int jtag_ntrst_assert_width = 0; /* width of assertion */
108 * Contains a single callback along with a pointer that will be passed
109 * when an event occurs.
111 struct jtag_event_callback {
113 jtag_event_handler_t callback;
114 /// the private data to pass to the callback
116 /// the next callback
117 struct jtag_event_callback* next;
120 /* callbacks to inform high-level handlers about JTAG state changes */
121 static struct jtag_event_callback *jtag_event_callbacks;
124 static int speed_khz = 0;
125 /* speed to fallback to when RCLK is requested but not supported */
126 static int rclk_fallback_speed_khz = 0;
127 static enum {CLOCK_MODE_UNSELECTED, CLOCK_MODE_KHZ, CLOCK_MODE_RCLK} clock_mode;
128 static int jtag_speed = 0;
130 static struct jtag_interface *jtag = NULL;
133 const struct swd_driver *swd = NULL;
136 struct jtag_interface *jtag_interface = NULL;
138 void jtag_set_flush_queue_sleep(int ms)
140 jtag_flush_queue_sleep = ms;
143 void jtag_set_error(int error)
145 if ((error == ERROR_OK) || (jtag_error != ERROR_OK))
150 int jtag_error_clear(void)
152 int temp = jtag_error;
153 jtag_error = ERROR_OK;
159 static bool jtag_poll = 1;
161 bool is_jtag_poll_safe(void)
163 /* Polling can be disabled explicitly with set_enabled(false).
164 * It is also implicitly disabled while TRST is active and
165 * while SRST is gating the JTAG clock.
167 if (!jtag_poll || jtag_trst != 0)
169 return jtag_srst == 0 || (jtag_reset_config & RESET_SRST_NO_GATING);
172 bool jtag_poll_get_enabled(void)
177 void jtag_poll_set_enabled(bool value)
184 struct jtag_tap *jtag_all_taps(void)
186 return __jtag_all_taps;
189 unsigned jtag_tap_count(void)
191 return jtag_num_taps;
194 unsigned jtag_tap_count_enabled(void)
196 struct jtag_tap *t = jtag_all_taps();
207 /// Append a new TAP to the chain of all taps.
208 void jtag_tap_add(struct jtag_tap *t)
210 t->abs_chain_position = jtag_num_taps++;
212 struct jtag_tap **tap = &__jtag_all_taps;
214 tap = &(*tap)->next_tap;
218 /* returns a pointer to the n-th device in the scan chain */
219 struct jtag_tap *jtag_tap_by_position(unsigned n)
221 struct jtag_tap *t = jtag_all_taps();
229 struct jtag_tap *jtag_tap_by_string(const char *s)
231 /* try by name first */
232 struct jtag_tap *t = jtag_all_taps();
236 if (0 == strcmp(t->dotted_name, s))
241 /* no tap found by name, so try to parse the name as a number */
243 if (parse_uint(s, &n) != ERROR_OK)
246 /* FIXME remove this numeric fallback code late June 2010, along
247 * with all info in the User's Guide that TAPs have numeric IDs.
248 * Also update "scan_chain" output to not display the numbers.
250 t = jtag_tap_by_position(n);
252 LOG_WARNING("Specify TAP '%s' by name, not number %u",
258 struct jtag_tap* jtag_tap_next_enabled(struct jtag_tap* p)
260 p = p ? p->next_tap : jtag_all_taps();
270 const char *jtag_tap_name(const struct jtag_tap *tap)
272 return (tap == NULL) ? "(unknown)" : tap->dotted_name;
276 int jtag_register_event_callback(jtag_event_handler_t callback, void *priv)
278 struct jtag_event_callback **callbacks_p = &jtag_event_callbacks;
280 if (callback == NULL)
282 return ERROR_INVALID_ARGUMENTS;
287 while ((*callbacks_p)->next)
288 callbacks_p = &((*callbacks_p)->next);
289 callbacks_p = &((*callbacks_p)->next);
292 (*callbacks_p) = malloc(sizeof(struct jtag_event_callback));
293 (*callbacks_p)->callback = callback;
294 (*callbacks_p)->priv = priv;
295 (*callbacks_p)->next = NULL;
300 int jtag_unregister_event_callback(jtag_event_handler_t callback, void *priv)
302 struct jtag_event_callback **p = &jtag_event_callbacks, *temp;
304 if (callback == NULL)
306 return ERROR_INVALID_ARGUMENTS;
311 if (((*p)->priv != priv) || ((*p)->callback != callback))
325 int jtag_call_event_callbacks(enum jtag_event event)
327 struct jtag_event_callback *callback = jtag_event_callbacks;
329 LOG_DEBUG("jtag event: %s", jtag_event_strings[event]);
333 struct jtag_event_callback *next;
335 /* callback may remove itself */
336 next = callback->next;
337 callback->callback(event, callback->priv);
344 static void jtag_checks(void)
346 assert(jtag_trst == 0);
349 static void jtag_prelude(tap_state_t state)
353 assert(state != TAP_INVALID);
355 cmd_queue_cur_state = state;
358 void jtag_add_ir_scan_noverify(struct jtag_tap *active, const struct scan_field *in_fields,
363 int retval = interface_jtag_add_ir_scan(active, in_fields, state);
364 jtag_set_error(retval);
367 static void jtag_add_ir_scan_noverify_callback(struct jtag_tap *active, int dummy, const struct scan_field *in_fields,
370 jtag_add_ir_scan_noverify(active, in_fields, state);
373 void jtag_add_ir_scan(struct jtag_tap *active, struct scan_field *in_fields, tap_state_t state)
375 assert(state != TAP_RESET);
377 if (jtag_verify && jtag_verify_capture_ir)
379 /* 8 x 32 bit id's is enough for all invocations */
381 /* if we are to run a verification of the ir scan, we need to get the input back.
382 * We may have to allocate space if the caller didn't ask for the input back.
384 in_fields->check_value = active->expected;
385 in_fields->check_mask = active->expected_mask;
386 jtag_add_scan_check(active, jtag_add_ir_scan_noverify_callback, 1, in_fields, state);
389 jtag_add_ir_scan_noverify(active, in_fields, state);
393 void jtag_add_plain_ir_scan(int num_bits, const uint8_t *out_bits, uint8_t *in_bits,
396 assert(out_bits != NULL);
397 assert(state != TAP_RESET);
401 int retval = interface_jtag_add_plain_ir_scan(
402 num_bits, out_bits, in_bits, state);
403 jtag_set_error(retval);
406 static int jtag_check_value_inner(uint8_t *captured, uint8_t *in_check_value,
407 uint8_t *in_check_mask, int num_bits);
409 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)
411 return jtag_check_value_inner((uint8_t *)data0, (uint8_t *)data1, (uint8_t *)data2, (int)data3);
414 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),
415 int in_num_fields, struct scan_field *in_fields, tap_state_t state)
417 for (int i = 0; i < in_num_fields; i++)
419 struct scan_field *field = &in_fields[i];
420 field->allocated = 0;
422 if (field->check_value || field->in_value)
424 interface_jtag_add_scan_check_alloc(field);
428 jtag_add_scan(active, in_num_fields, in_fields, state);
430 for (int i = 0; i < in_num_fields; i++)
432 if ((in_fields[i].check_value != NULL) && (in_fields[i].in_value != NULL))
434 /* this is synchronous for a minidriver */
435 jtag_add_callback4(jtag_check_value_mask_callback, (jtag_callback_data_t)in_fields[i].in_value,
436 (jtag_callback_data_t)in_fields[i].check_value,
437 (jtag_callback_data_t)in_fields[i].check_mask,
438 (jtag_callback_data_t)in_fields[i].num_bits);
440 if (in_fields[i].allocated)
442 free(in_fields[i].in_value);
444 if (in_fields[i].modified)
446 in_fields[i].in_value = NULL;
451 void jtag_add_dr_scan_check(struct jtag_tap *active, int in_num_fields, struct scan_field *in_fields, tap_state_t state)
455 jtag_add_scan_check(active, jtag_add_dr_scan, in_num_fields, in_fields, state);
458 jtag_add_dr_scan(active, in_num_fields, in_fields, state);
463 void jtag_add_dr_scan(struct jtag_tap *active, int in_num_fields, const struct scan_field *in_fields,
466 assert(state != TAP_RESET);
471 retval = interface_jtag_add_dr_scan(active, in_num_fields, in_fields, state);
472 jtag_set_error(retval);
475 void jtag_add_plain_dr_scan(int num_bits, const uint8_t *out_bits, uint8_t *in_bits,
478 assert(out_bits != NULL);
479 assert(state != TAP_RESET);
484 retval = interface_jtag_add_plain_dr_scan(num_bits, out_bits, in_bits, state);
485 jtag_set_error(retval);
488 void jtag_add_tlr(void)
490 jtag_prelude(TAP_RESET);
491 jtag_set_error(interface_jtag_add_tlr());
493 /* NOTE: order here matches TRST path in jtag_add_reset() */
494 jtag_call_event_callbacks(JTAG_TRST_ASSERTED);
495 jtag_notify_event(JTAG_TRST_ASSERTED);
499 * If supported by the underlying adapter, this clocks a raw bit sequence
500 * onto TMS for switching betwen JTAG and SWD modes.
502 * DO NOT use this to bypass the integrity checks and logging provided
503 * by the jtag_add_pathmove() and jtag_add_statemove() calls.
505 * @param nbits How many bits to clock out.
506 * @param seq The bit sequence. The LSB is bit 0 of seq[0].
507 * @param state The JTAG tap state to record on completion. Use
508 * TAP_INVALID to represent being in in SWD mode.
510 * @todo Update naming conventions to stop assuming everything is JTAG.
512 int jtag_add_tms_seq(unsigned nbits, const uint8_t *seq, enum tap_state state)
516 if (!(jtag->supported & DEBUG_CAP_TMS_SEQ))
517 return ERROR_JTAG_NOT_IMPLEMENTED;
520 cmd_queue_cur_state = state;
522 retval = interface_add_tms_seq(nbits, seq, state);
523 jtag_set_error(retval);
527 void jtag_add_pathmove(int num_states, const tap_state_t *path)
529 tap_state_t cur_state = cmd_queue_cur_state;
531 /* the last state has to be a stable state */
532 if (!tap_is_state_stable(path[num_states - 1]))
534 LOG_ERROR("BUG: TAP path doesn't finish in a stable state");
535 jtag_set_error(ERROR_JTAG_NOT_STABLE_STATE);
539 for (int i = 0; i < num_states; i++)
541 if (path[i] == TAP_RESET)
543 LOG_ERROR("BUG: TAP_RESET is not a valid state for pathmove sequences");
544 jtag_set_error(ERROR_JTAG_STATE_INVALID);
548 if (tap_state_transition(cur_state, true) != path[i]
549 && tap_state_transition(cur_state, false) != path[i])
551 LOG_ERROR("BUG: %s -> %s isn't a valid TAP transition",
552 tap_state_name(cur_state), tap_state_name(path[i]));
553 jtag_set_error(ERROR_JTAG_TRANSITION_INVALID);
561 jtag_set_error(interface_jtag_add_pathmove(num_states, path));
562 cmd_queue_cur_state = path[num_states - 1];
565 int jtag_add_statemove(tap_state_t goal_state)
567 tap_state_t cur_state = cmd_queue_cur_state;
569 if (goal_state != cur_state)
571 LOG_DEBUG("cur_state=%s goal_state=%s",
572 tap_state_name(cur_state),
573 tap_state_name(goal_state));
576 /* If goal is RESET, be paranoid and force that that transition
577 * (e.g. five TCK cycles, TMS high). Else trust "cur_state".
579 if (goal_state == TAP_RESET)
581 else if (goal_state == cur_state)
582 /* nothing to do */ ;
584 else if (tap_is_state_stable(cur_state) && tap_is_state_stable(goal_state))
586 unsigned tms_bits = tap_get_tms_path(cur_state, goal_state);
587 unsigned tms_count = tap_get_tms_path_len(cur_state, goal_state);
588 tap_state_t moves[8];
589 assert(tms_count < ARRAY_SIZE(moves));
591 for (unsigned i = 0; i < tms_count; i++, tms_bits >>= 1)
593 bool bit = tms_bits & 1;
595 cur_state = tap_state_transition(cur_state, bit);
596 moves[i] = cur_state;
599 jtag_add_pathmove(tms_count, moves);
601 else if (tap_state_transition(cur_state, true) == goal_state
602 || tap_state_transition(cur_state, false) == goal_state)
604 jtag_add_pathmove(1, &goal_state);
613 void jtag_add_runtest(int num_cycles, tap_state_t state)
616 jtag_set_error(interface_jtag_add_runtest(num_cycles, state));
620 void jtag_add_clocks(int num_cycles)
622 if (!tap_is_state_stable(cmd_queue_cur_state))
624 LOG_ERROR("jtag_add_clocks() called with TAP in unstable state \"%s\"",
625 tap_state_name(cmd_queue_cur_state));
626 jtag_set_error(ERROR_JTAG_NOT_STABLE_STATE);
633 jtag_set_error(interface_jtag_add_clocks(num_cycles));
637 void jtag_add_reset(int req_tlr_or_trst, int req_srst)
639 int trst_with_tlr = 0;
643 /* Without SRST, we must use target-specific JTAG operations
644 * on each target; callers should not be requesting SRST when
645 * that signal doesn't exist.
647 * RESET_SRST_PULLS_TRST is a board or chip level quirk, which
648 * can kick in even if the JTAG adapter can't drive TRST.
651 if (!(jtag_reset_config & RESET_HAS_SRST)) {
652 LOG_ERROR("BUG: can't assert SRST");
653 jtag_set_error(ERROR_FAIL);
656 if ((jtag_reset_config & RESET_SRST_PULLS_TRST) != 0
657 && !req_tlr_or_trst) {
658 LOG_ERROR("BUG: can't assert only SRST");
659 jtag_set_error(ERROR_FAIL);
665 /* JTAG reset (entry to TAP_RESET state) can always be achieved
666 * using TCK and TMS; that may go through a TAP_{IR,DR}UPDATE
667 * state first. TRST accelerates it, and bypasses those states.
669 * RESET_TRST_PULLS_SRST is a board or chip level quirk, which
670 * can kick in even if the JTAG adapter can't drive SRST.
672 if (req_tlr_or_trst) {
673 if (!(jtag_reset_config & RESET_HAS_TRST))
675 else if ((jtag_reset_config & RESET_TRST_PULLS_SRST) != 0
682 /* Maybe change TRST and/or SRST signal state */
683 if (jtag_srst != new_srst || jtag_trst != new_trst) {
686 retval = interface_jtag_add_reset(new_trst, new_srst);
687 if (retval != ERROR_OK)
688 jtag_set_error(retval);
690 retval = jtag_execute_queue();
692 if (retval != ERROR_OK) {
693 LOG_ERROR("TRST/SRST error");
698 /* SRST resets everything hooked up to that signal */
699 if (jtag_srst != new_srst) {
700 jtag_srst = new_srst;
703 LOG_DEBUG("SRST line asserted");
704 if (adapter_nsrst_assert_width)
705 jtag_add_sleep(adapter_nsrst_assert_width * 1000);
708 LOG_DEBUG("SRST line released");
709 if (adapter_nsrst_delay)
710 jtag_add_sleep(adapter_nsrst_delay * 1000);
714 /* Maybe enter the JTAG TAP_RESET state ...
715 * - using only TMS, TCK, and the JTAG state machine
716 * - or else more directly, using TRST
718 * TAP_RESET should be invisible to non-debug parts of the system.
721 LOG_DEBUG("JTAG reset with TLR instead of TRST");
724 } else if (jtag_trst != new_trst) {
725 jtag_trst = new_trst;
727 LOG_DEBUG("TRST line asserted");
728 tap_set_state(TAP_RESET);
729 if (jtag_ntrst_assert_width)
730 jtag_add_sleep(jtag_ntrst_assert_width * 1000);
732 LOG_DEBUG("TRST line released");
733 if (jtag_ntrst_delay)
734 jtag_add_sleep(jtag_ntrst_delay * 1000);
736 /* We just asserted nTRST, so we're now in TAP_RESET.
737 * Inform possible listeners about this, now that
738 * JTAG instructions and data can be shifted. This
739 * sequence must match jtag_add_tlr().
741 jtag_call_event_callbacks(JTAG_TRST_ASSERTED);
742 jtag_notify_event(JTAG_TRST_ASSERTED);
747 void jtag_add_sleep(uint32_t us)
749 /// @todo Here, keep_alive() appears to be a layering violation!!!
751 jtag_set_error(interface_jtag_add_sleep(us));
754 static int jtag_check_value_inner(uint8_t *captured, uint8_t *in_check_value,
755 uint8_t *in_check_mask, int num_bits)
757 int retval = ERROR_OK;
761 compare_failed = buf_cmp_mask(captured, in_check_value, in_check_mask, num_bits);
763 compare_failed = buf_cmp(captured, in_check_value, num_bits);
765 if (compare_failed) {
766 char *captured_str, *in_check_value_str;
767 int bits = (num_bits > DEBUG_JTAG_IOZ)
771 /* NOTE: we've lost diagnostic context here -- 'which tap' */
773 captured_str = buf_to_str(captured, bits, 16);
774 in_check_value_str = buf_to_str(in_check_value, bits, 16);
776 LOG_WARNING("Bad value '%s' captured during DR or IR scan:",
778 LOG_WARNING(" check_value: 0x%s", in_check_value_str);
781 free(in_check_value_str);
784 char *in_check_mask_str;
786 in_check_mask_str = buf_to_str(in_check_mask, bits, 16);
787 LOG_WARNING(" check_mask: 0x%s", in_check_mask_str);
788 free(in_check_mask_str);
791 retval = ERROR_JTAG_QUEUE_FAILED;
796 void jtag_check_value_mask(struct scan_field *field, uint8_t *value, uint8_t *mask)
798 assert(field->in_value != NULL);
802 /* no checking to do */
806 jtag_execute_queue_noclear();
808 int retval = jtag_check_value_inner(field->in_value, value, mask, field->num_bits);
809 jtag_set_error(retval);
814 int default_interface_jtag_execute_queue(void)
818 LOG_ERROR("No JTAG interface configured yet. "
819 "Issue 'init' command in startup scripts "
820 "before communicating with targets.");
824 return jtag->execute_queue();
827 void jtag_execute_queue_noclear(void)
829 jtag_flush_queue_count++;
830 jtag_set_error(interface_jtag_execute_queue());
832 if (jtag_flush_queue_sleep > 0)
834 /* For debug purposes it can be useful to test performance
835 * or behavior when delaying after flushing the queue,
836 * e.g. to simulate long roundtrip times.
838 usleep(jtag_flush_queue_sleep * 1000);
842 int jtag_get_flush_queue_count(void)
844 return jtag_flush_queue_count;
847 int jtag_execute_queue(void)
849 jtag_execute_queue_noclear();
850 return jtag_error_clear();
853 static int jtag_reset_callback(enum jtag_event event, void *priv)
855 struct jtag_tap *tap = priv;
857 if (event == JTAG_TRST_ASSERTED)
859 tap->enabled = !tap->disabled_after_reset;
861 /* current instruction is either BYPASS or IDCODE */
862 buf_set_ones(tap->cur_instr, tap->ir_length);
869 /* sleep at least us microseconds. When we sleep more than 1000ms we
870 * do an alive sleep, i.e. keep GDB alive. Note that we could starve
871 * GDB if we slept for <1000ms many times.
873 void jtag_sleep(uint32_t us)
878 alive_sleep((us+999)/1000);
881 /* Maximum number of enabled JTAG devices we expect in the scan chain,
882 * plus one (to detect garbage at the end). Devices that don't support
883 * IDCODE take up fewer bits, possibly allowing a few more devices.
885 #define JTAG_MAX_CHAIN_SIZE 20
887 #define EXTRACT_MFG(X) (((X) & 0xffe) >> 1)
888 #define EXTRACT_PART(X) (((X) & 0xffff000) >> 12)
889 #define EXTRACT_VER(X) (((X) & 0xf0000000) >> 28)
891 /* A reserved manufacturer ID is used in END_OF_CHAIN_FLAG, so we
892 * know that no valid TAP will have it as an IDCODE value.
894 #define END_OF_CHAIN_FLAG 0x000000ff
896 /* a larger IR length than we ever expect to autoprobe */
897 #define JTAG_IRLEN_MAX 60
899 static int jtag_examine_chain_execute(uint8_t *idcode_buffer, unsigned num_idcode)
901 struct scan_field field = {
902 .num_bits = num_idcode * 32,
903 .out_value = idcode_buffer,
904 .in_value = idcode_buffer,
907 // initialize to the end of chain ID value
908 for (unsigned i = 0; i < JTAG_MAX_CHAIN_SIZE; i++)
909 buf_set_u32(idcode_buffer, i * 32, 32, END_OF_CHAIN_FLAG);
911 jtag_add_plain_dr_scan(field.num_bits, field.out_value, field.in_value, TAP_DRPAUSE);
913 return jtag_execute_queue();
916 static bool jtag_examine_chain_check(uint8_t *idcodes, unsigned count)
918 uint8_t zero_check = 0x0;
919 uint8_t one_check = 0xff;
921 for (unsigned i = 0; i < count * 4; i++)
923 zero_check |= idcodes[i];
924 one_check &= idcodes[i];
927 /* if there wasn't a single non-zero bit or if all bits were one,
928 * the scan is not valid. We wrote a mix of both values; either
930 * - There's a hardware issue (almost certainly):
931 * + all-zeroes can mean a target stuck in JTAG reset
932 * + all-ones tends to mean no target
933 * - The scan chain is WAY longer than we can handle, *AND* either
934 * + there are several hundreds of TAPs in bypass, or
935 * + at least a few dozen TAPs all have an all-ones IDCODE
937 if (zero_check == 0x00 || one_check == 0xff)
939 LOG_ERROR("JTAG scan chain interrogation failed: all %s",
940 (zero_check == 0x00) ? "zeroes" : "ones");
941 LOG_ERROR("Check JTAG interface, timings, target power, etc.");
947 static void jtag_examine_chain_display(enum log_levels level, const char *msg,
948 const char *name, uint32_t idcode)
950 log_printf_lf(level, __FILE__, __LINE__, __FUNCTION__,
951 "JTAG tap: %s %16.16s: 0x%08x "
952 "(mfg: 0x%3.3x, part: 0x%4.4x, ver: 0x%1.1x)",
954 (unsigned int)idcode,
955 (unsigned int)EXTRACT_MFG(idcode),
956 (unsigned int)EXTRACT_PART(idcode),
957 (unsigned int)EXTRACT_VER(idcode));
960 static bool jtag_idcode_is_final(uint32_t idcode)
963 * Some devices, such as AVR8, will output all 1's instead
964 * of TDI input value at end of chain. Allow those values
965 * instead of failing.
967 return idcode == END_OF_CHAIN_FLAG || idcode == 0xFFFFFFFF;
971 * This helper checks that remaining bits in the examined chain data are
972 * all as expected, but a single JTAG device requires only 64 bits to be
973 * read back correctly. This can help identify and diagnose problems
974 * with the JTAG chain earlier, gives more helpful/explicit error messages.
975 * Returns TRUE iff garbage was found.
977 static bool jtag_examine_chain_end(uint8_t *idcodes, unsigned count, unsigned max)
979 bool triggered = false;
980 for (; count < max - 31; count += 32)
982 uint32_t idcode = buf_get_u32(idcodes, count, 32);
984 /* do not trigger the warning if the data looks good */
985 if (jtag_idcode_is_final(idcode))
987 LOG_WARNING("Unexpected idcode after end of chain: %d 0x%08x",
988 count, (unsigned int)idcode);
994 static bool jtag_examine_chain_match_tap(const struct jtag_tap *tap)
996 uint32_t idcode = tap->idcode;
998 /* ignore expected BYPASS codes; warn otherwise */
999 if (0 == tap->expected_ids_cnt && !idcode)
1002 /* optionally ignore the JTAG version field */
1003 uint32_t mask = tap->ignore_version ? ~(0xff << 24) : ~0;
1007 /* Loop over the expected identification codes and test for a match */
1008 unsigned ii, limit = tap->expected_ids_cnt;
1010 for (ii = 0; ii < limit; ii++)
1012 uint32_t expected = tap->expected_ids[ii] & mask;
1014 if (idcode == expected)
1017 /* treat "-expected-id 0" as a "don't-warn" wildcard */
1018 if (0 == tap->expected_ids[ii])
1022 /* If none of the expected ids matched, warn */
1023 jtag_examine_chain_display(LOG_LVL_WARNING, "UNEXPECTED",
1024 tap->dotted_name, tap->idcode);
1025 for (ii = 0; ii < limit; ii++)
1029 snprintf(msg, sizeof(msg), "expected %u of %u", ii + 1, limit);
1030 jtag_examine_chain_display(LOG_LVL_ERROR, msg,
1031 tap->dotted_name, tap->expected_ids[ii]);
1036 /* Try to examine chain layout according to IEEE 1149.1 §12
1037 * This is called a "blind interrogation" of the scan chain.
1039 static int jtag_examine_chain(void)
1041 uint8_t idcode_buffer[JTAG_MAX_CHAIN_SIZE * 4];
1045 bool autoprobe = false;
1047 /* DR scan to collect BYPASS or IDCODE register contents.
1048 * Then make sure the scan data has both ones and zeroes.
1050 LOG_DEBUG("DR scan interrogation for IDCODE/BYPASS");
1051 retval = jtag_examine_chain_execute(idcode_buffer, JTAG_MAX_CHAIN_SIZE);
1052 if (retval != ERROR_OK)
1054 if (!jtag_examine_chain_check(idcode_buffer, JTAG_MAX_CHAIN_SIZE))
1055 return ERROR_JTAG_INIT_FAILED;
1057 /* point at the 1st tap */
1058 struct jtag_tap *tap = jtag_tap_next_enabled(NULL);
1064 tap && bit_count < (JTAG_MAX_CHAIN_SIZE * 32) - 31;
1065 tap = jtag_tap_next_enabled(tap))
1067 uint32_t idcode = buf_get_u32(idcode_buffer, bit_count, 32);
1069 if ((idcode & 1) == 0)
1071 /* Zero for LSB indicates a device in bypass */
1072 LOG_INFO("TAP %s does not have IDCODE",
1075 tap->hasidcode = false;
1081 /* Friendly devices support IDCODE */
1082 tap->hasidcode = true;
1083 jtag_examine_chain_display(LOG_LVL_INFO,
1085 tap->dotted_name, idcode);
1089 tap->idcode = idcode;
1091 /* ensure the TAP ID matches what was expected */
1092 if (!jtag_examine_chain_match_tap(tap))
1093 retval = ERROR_JTAG_INIT_SOFT_FAIL;
1096 /* Fail if too many TAPs were enabled for us to verify them all. */
1098 LOG_ERROR("Too many TAPs enabled; '%s' ignored.",
1100 return ERROR_JTAG_INIT_FAILED;
1103 /* if autoprobing, the tap list is still empty ... populate it! */
1104 while (autoprobe && bit_count < (JTAG_MAX_CHAIN_SIZE * 32) - 31) {
1108 /* Is there another TAP? */
1109 idcode = buf_get_u32(idcode_buffer, bit_count, 32);
1110 if (jtag_idcode_is_final(idcode))
1113 /* Default everything in this TAP except IR length.
1115 * REVISIT create a jtag_alloc(chip, tap) routine, and
1116 * share it with jim_newtap_cmd().
1118 tap = calloc(1, sizeof *tap);
1122 sprintf(buf, "auto%d", tapcount++);
1123 tap->chip = strdup(buf);
1124 tap->tapname = strdup("tap");
1126 sprintf(buf, "%s.%s", tap->chip, tap->tapname);
1127 tap->dotted_name = strdup(buf);
1129 /* tap->ir_length == 0 ... signifying irlen autoprobe */
1130 tap->ir_capture_mask = 0x03;
1131 tap->ir_capture_value = 0x01;
1133 tap->enabled = true;
1135 if ((idcode & 1) == 0) {
1137 tap->hasidcode = false;
1140 tap->hasidcode = true;
1141 tap->idcode = idcode;
1143 tap->expected_ids_cnt = 1;
1144 tap->expected_ids = malloc(sizeof(uint32_t));
1145 tap->expected_ids[0] = idcode;
1148 LOG_WARNING("AUTO %s - use \"jtag newtap "
1149 "%s %s -expected-id 0x%8.8" PRIx32 " ...\"",
1150 tap->dotted_name, tap->chip, tap->tapname,
1156 /* After those IDCODE or BYPASS register values should be
1157 * only the data we fed into the scan chain.
1159 if (jtag_examine_chain_end(idcode_buffer, bit_count,
1160 8 * sizeof(idcode_buffer))) {
1161 LOG_ERROR("double-check your JTAG setup (interface, "
1162 "speed, missing TAPs, ...)");
1163 return ERROR_JTAG_INIT_FAILED;
1166 /* Return success or, for backwards compatibility if only
1167 * some IDCODE values mismatched, a soft/continuable fault.
1173 * Validate the date loaded by entry to the Capture-IR state, to help
1174 * find errors related to scan chain configuration (wrong IR lengths)
1177 * Entry state can be anything. On non-error exit, all TAPs are in
1178 * bypass mode. On error exits, the scan chain is reset.
1180 static int jtag_validate_ircapture(void)
1182 struct jtag_tap *tap;
1183 int total_ir_length = 0;
1184 uint8_t *ir_test = NULL;
1185 struct scan_field field;
1190 /* when autoprobing, accomodate huge IR lengths */
1191 for (tap = NULL, total_ir_length = 0;
1192 (tap = jtag_tap_next_enabled(tap)) != NULL;
1193 total_ir_length += tap->ir_length) {
1194 if (tap->ir_length == 0)
1195 total_ir_length += JTAG_IRLEN_MAX;
1198 /* increase length to add 2 bit sentinel after scan */
1199 total_ir_length += 2;
1201 ir_test = malloc(DIV_ROUND_UP(total_ir_length, 8));
1202 if (ir_test == NULL)
1205 /* after this scan, all TAPs will capture BYPASS instructions */
1206 buf_set_ones(ir_test, total_ir_length);
1208 field.num_bits = total_ir_length;
1209 field.out_value = ir_test;
1210 field.in_value = ir_test;
1212 jtag_add_plain_ir_scan(field.num_bits, field.out_value, field.in_value, TAP_IDLE);
1214 LOG_DEBUG("IR capture validation scan");
1215 retval = jtag_execute_queue();
1216 if (retval != ERROR_OK)
1223 tap = jtag_tap_next_enabled(tap);
1228 /* If we're autoprobing, guess IR lengths. They must be at
1229 * least two bits. Guessing will fail if (a) any TAP does
1230 * not conform to the JTAG spec; or (b) when the upper bits
1231 * captured from some conforming TAP are nonzero. Or if
1232 * (c) an IR length is longer than 32 bits -- which is only
1233 * an implementation limit, which could someday be raised.
1235 * REVISIT optimization: if there's a *single* TAP we can
1236 * lift restrictions (a) and (b) by scanning a recognizable
1237 * pattern before the all-ones BYPASS. Check for where the
1238 * pattern starts in the result, instead of an 0...01 value.
1240 * REVISIT alternative approach: escape to some tcl code
1241 * which could provide more knowledge, based on IDCODE; and
1242 * only guess when that has no success.
1244 if (tap->ir_length == 0) {
1246 while ((val = buf_get_u32(ir_test, chain_pos,
1247 tap->ir_length + 1)) == 1
1248 && tap->ir_length <= 32) {
1251 LOG_WARNING("AUTO %s - use \"... -irlen %d\"",
1252 jtag_tap_name(tap), tap->ir_length);
1255 /* Validate the two LSBs, which must be 01 per JTAG spec.
1257 * Or ... more bits could be provided by TAP declaration.
1258 * Plus, some taps (notably in i.MX series chips) violate
1259 * this part of the JTAG spec, so their capture mask/value
1260 * attributes might disable this test.
1262 val = buf_get_u32(ir_test, chain_pos, tap->ir_length);
1263 if ((val & tap->ir_capture_mask) != tap->ir_capture_value) {
1264 LOG_ERROR("%s: IR capture error; saw 0x%0*x not 0x%0*x",
1266 (tap->ir_length + 7) / tap->ir_length,
1268 (tap->ir_length + 7) / tap->ir_length,
1269 (unsigned) tap->ir_capture_value);
1271 retval = ERROR_JTAG_INIT_FAILED;
1274 LOG_DEBUG("%s: IR capture 0x%0*x", jtag_tap_name(tap),
1275 (tap->ir_length + 7) / tap->ir_length, val);
1276 chain_pos += tap->ir_length;
1279 /* verify the '11' sentinel we wrote is returned at the end */
1280 val = buf_get_u32(ir_test, chain_pos, 2);
1283 char *cbuf = buf_to_str(ir_test, total_ir_length, 16);
1285 LOG_ERROR("IR capture error at bit %d, saw 0x%s not 0x...3",
1288 retval = ERROR_JTAG_INIT_FAILED;
1293 if (retval != ERROR_OK) {
1295 jtag_execute_queue();
1301 void jtag_tap_init(struct jtag_tap *tap)
1303 unsigned ir_len_bits;
1304 unsigned ir_len_bytes;
1306 /* if we're autoprobing, cope with potentially huge ir_length */
1307 ir_len_bits = tap->ir_length ? : JTAG_IRLEN_MAX;
1308 ir_len_bytes = DIV_ROUND_UP(ir_len_bits, 8);
1310 tap->expected = calloc(1, ir_len_bytes);
1311 tap->expected_mask = calloc(1, ir_len_bytes);
1312 tap->cur_instr = malloc(ir_len_bytes);
1314 /// @todo cope better with ir_length bigger than 32 bits
1315 if (ir_len_bits > 32)
1318 buf_set_u32(tap->expected, 0, ir_len_bits, tap->ir_capture_value);
1319 buf_set_u32(tap->expected_mask, 0, ir_len_bits, tap->ir_capture_mask);
1321 // TAP will be in bypass mode after jtag_validate_ircapture()
1323 buf_set_ones(tap->cur_instr, tap->ir_length);
1325 // register the reset callback for the TAP
1326 jtag_register_event_callback(&jtag_reset_callback, tap);
1328 LOG_DEBUG("Created Tap: %s @ abs position %d, "
1329 "irlen %d, capture: 0x%x mask: 0x%x", tap->dotted_name,
1330 tap->abs_chain_position, tap->ir_length,
1331 (unsigned) tap->ir_capture_value,
1332 (unsigned) tap->ir_capture_mask);
1336 void jtag_tap_free(struct jtag_tap *tap)
1338 jtag_unregister_event_callback(&jtag_reset_callback, tap);
1340 /// @todo is anything missing? no memory leaks please
1341 free((void *)tap->expected);
1342 free((void *)tap->expected_ids);
1343 free((void *)tap->chip);
1344 free((void *)tap->tapname);
1345 free((void *)tap->dotted_name);
1350 * Do low-level setup like initializing registers, output signals,
1353 int adapter_init(struct command_context *cmd_ctx)
1358 if (!jtag_interface)
1360 /* nothing was previously specified by "interface" command */
1361 LOG_ERROR("Debug Adapter has to be specified, "
1362 "see \"interface\" command");
1363 return ERROR_JTAG_INVALID_INTERFACE;
1367 retval = jtag_interface->init();
1368 if (retval != ERROR_OK)
1372 jtag = jtag_interface;
1374 /* LEGACY SUPPORT ... adapter drivers must declare what
1375 * transports they allow. Until they all do so, assume
1376 * the legacy drivers are JTAG-only
1378 if (!transports_are_declared()) {
1379 LOG_ERROR("Adapter driver '%s' did not declare "
1380 "which transports it allows; assuming "
1381 "JTAG-only", jtag->name);
1382 retval = allow_transports(cmd_ctx, jtag_only);
1383 if (retval != ERROR_OK)
1387 if (CLOCK_MODE_UNSELECTED == clock_mode)
1389 LOG_ERROR("An adapter speed is not selected in the init script."
1390 " Insert a call to adapter_khz or jtag_rclk to proceed.");
1391 return ERROR_JTAG_INIT_FAILED;
1394 int requested_khz = jtag_get_speed_khz();
1395 int actual_khz = requested_khz;
1396 int jtag_speed_var = 0;
1397 retval = jtag_get_speed(&jtag_speed_var);
1398 if (retval != ERROR_OK)
1400 retval = jtag->speed(jtag_speed_var);
1401 if (retval != ERROR_OK)
1403 retval = jtag_get_speed_readable(&actual_khz);
1404 if (ERROR_OK != retval)
1405 LOG_INFO("adapter-specific clock speed value %d", jtag_speed_var);
1406 else if (actual_khz)
1408 /* Adaptive clocking -- JTAG-specific */
1409 if ((CLOCK_MODE_RCLK == clock_mode)
1410 || ((CLOCK_MODE_KHZ == clock_mode) && !requested_khz))
1412 LOG_INFO("RCLK (adaptive clock speed) not supported - fallback to %d kHz"
1416 LOG_INFO("clock speed %d kHz", actual_khz);
1419 LOG_INFO("RCLK (adaptive clock speed)");
1424 int jtag_init_inner(struct command_context *cmd_ctx)
1426 struct jtag_tap *tap;
1428 bool issue_setup = true;
1430 LOG_DEBUG("Init JTAG chain");
1432 tap = jtag_tap_next_enabled(NULL);
1434 /* Once JTAG itself is properly set up, and the scan chain
1435 * isn't absurdly large, IDCODE autoprobe should work fine.
1437 * But ... IRLEN autoprobe can fail even on systems which
1438 * are fully conformant to JTAG. Also, JTAG setup can be
1439 * quite finicky on some systems.
1441 * REVISIT: if TAP autoprobe works OK, then in many cases
1442 * we could escape to tcl code and set up targets based on
1443 * the TAP's IDCODE values.
1445 LOG_WARNING("There are no enabled taps. "
1446 "AUTO PROBING MIGHT NOT WORK!!");
1448 /* REVISIT default clock will often be too fast ... */
1452 if ((retval = jtag_execute_queue()) != ERROR_OK)
1455 /* Examine DR values first. This discovers problems which will
1456 * prevent communication ... hardware issues like TDO stuck, or
1457 * configuring the wrong number of (enabled) TAPs.
1459 retval = jtag_examine_chain();
1462 /* complete success */
1465 /* For backward compatibility reasons, try coping with
1466 * configuration errors involving only ID mismatches.
1467 * We might be able to talk to the devices.
1469 * Also the device might be powered down during startup.
1471 * After OpenOCD starts, we can try to power on the device
1474 LOG_ERROR("Trying to use configured scan chain anyway...");
1475 issue_setup = false;
1479 /* Now look at IR values. Problems here will prevent real
1480 * communication. They mostly mean that the IR length is
1481 * wrong ... or that the IR capture value is wrong. (The
1482 * latter is uncommon, but easily worked around: provide
1483 * ircapture/irmask values during TAP setup.)
1485 retval = jtag_validate_ircapture();
1486 if (retval != ERROR_OK)
1488 /* The target might be powered down. The user
1489 * can power it up and reset it after firing
1492 issue_setup = false;
1496 jtag_notify_event(JTAG_TAP_EVENT_SETUP);
1498 LOG_WARNING("Bypassing JTAG setup events due to errors");
1504 int adapter_quit(void)
1506 if (!jtag || !jtag->quit)
1509 // close the JTAG interface
1510 int result = jtag->quit();
1511 if (ERROR_OK != result)
1512 LOG_ERROR("failed: %d", result);
1518 int jtag_init_reset(struct command_context *cmd_ctx)
1522 if ((retval = adapter_init(cmd_ctx)) != ERROR_OK)
1525 LOG_DEBUG("Initializing with hard TRST+SRST reset");
1528 * This procedure is used by default when OpenOCD triggers a reset.
1529 * It's now done through an overridable Tcl "init_reset" wrapper.
1531 * This started out as a more powerful "get JTAG working" reset than
1532 * jtag_init_inner(), applying TRST because some chips won't activate
1533 * JTAG without a TRST cycle (presumed to be async, though some of
1534 * those chips synchronize JTAG activation using TCK).
1536 * But some chips only activate JTAG as part of an SRST cycle; SRST
1537 * got mixed in. So it became a hard reset routine, which got used
1538 * in more places, and which coped with JTAG reset being forced as
1539 * part of SRST (srst_pulls_trst).
1541 * And even more corner cases started to surface: TRST and/or SRST
1542 * assertion timings matter; some chips need other JTAG operations;
1543 * TRST/SRST sequences can need to be different from these, etc.
1545 * Systems should override that wrapper to support system-specific
1546 * requirements that this not-fully-generic code doesn't handle.
1548 * REVISIT once Tcl code can read the reset_config modes, this won't
1549 * need to be a C routine at all...
1551 jtag_add_reset(1, 0); /* TAP_RESET, using TMS+TCK or TRST */
1552 if (jtag_reset_config & RESET_HAS_SRST)
1554 jtag_add_reset(1, 1);
1555 if ((jtag_reset_config & RESET_SRST_PULLS_TRST) == 0)
1556 jtag_add_reset(0, 1);
1558 jtag_add_reset(0, 0);
1559 if ((retval = jtag_execute_queue()) != ERROR_OK)
1562 /* Check that we can communication on the JTAG chain + eventually we want to
1563 * be able to perform enumeration only after OpenOCD has started
1564 * telnet and GDB server
1566 * That would allow users to more easily perform any magic they need to before
1569 return jtag_init_inner(cmd_ctx);
1572 int jtag_init(struct command_context *cmd_ctx)
1576 if ((retval = adapter_init(cmd_ctx)) != ERROR_OK)
1579 /* guard against oddball hardware: force resets to be inactive */
1580 jtag_add_reset(0, 0);
1581 if ((retval = jtag_execute_queue()) != ERROR_OK)
1584 if (Jim_Eval_Named(cmd_ctx->interp, "jtag_init", __FILE__, __LINE__) != JIM_OK)
1590 unsigned jtag_get_speed_khz(void)
1595 static int adapter_khz_to_speed(unsigned khz, int* speed)
1597 LOG_DEBUG("convert khz to interface specific speed value");
1601 LOG_DEBUG("have interface set up");
1603 int retval = jtag->khz(jtag_get_speed_khz(), &speed_div1);
1604 if (ERROR_OK != retval)
1608 *speed = speed_div1;
1613 static int jtag_rclk_to_speed(unsigned fallback_speed_khz, int* speed)
1615 int retval = adapter_khz_to_speed(0, speed);
1616 if ((ERROR_OK != retval) && fallback_speed_khz)
1618 LOG_DEBUG("trying fallback speed...");
1619 retval = adapter_khz_to_speed(fallback_speed_khz, speed);
1624 static int jtag_set_speed(int speed)
1627 /* this command can be called during CONFIG,
1628 * in which case jtag isn't initialized */
1629 return jtag ? jtag->speed(speed) : ERROR_OK;
1632 int jtag_config_khz(unsigned khz)
1634 LOG_DEBUG("handle jtag khz");
1635 clock_mode = CLOCK_MODE_KHZ;
1637 int retval = adapter_khz_to_speed(khz, &speed);
1638 return (ERROR_OK != retval) ? retval : jtag_set_speed(speed);
1641 int jtag_config_rclk(unsigned fallback_speed_khz)
1643 LOG_DEBUG("handle jtag rclk");
1644 clock_mode = CLOCK_MODE_RCLK;
1645 rclk_fallback_speed_khz = fallback_speed_khz;
1647 int retval = jtag_rclk_to_speed(fallback_speed_khz, &speed);
1648 return (ERROR_OK != retval) ? retval : jtag_set_speed(speed);
1651 int jtag_get_speed(int *speed)
1655 case CLOCK_MODE_KHZ:
1656 adapter_khz_to_speed(jtag_get_speed_khz(), speed);
1658 case CLOCK_MODE_RCLK:
1659 jtag_rclk_to_speed(rclk_fallback_speed_khz, speed);
1662 LOG_ERROR("BUG: unknown jtag clock mode");
1668 int jtag_get_speed_readable(int *khz)
1670 int jtag_speed_var = 0;
1671 int retval = jtag_get_speed(&jtag_speed_var);
1672 if (retval != ERROR_OK)
1674 return jtag ? jtag->speed_div(jtag_speed_var, khz) : ERROR_OK;
1677 void jtag_set_verify(bool enable)
1679 jtag_verify = enable;
1682 bool jtag_will_verify()
1687 void jtag_set_verify_capture_ir(bool enable)
1689 jtag_verify_capture_ir = enable;
1692 bool jtag_will_verify_capture_ir()
1694 return jtag_verify_capture_ir;
1697 int jtag_power_dropout(int *dropout)
1701 /* TODO: as the jtag interface is not valid all
1702 * we can do at the moment is exit OpenOCD */
1703 LOG_ERROR("No Valid JTAG Interface Configured.");
1706 return jtag->power_dropout(dropout);
1709 int jtag_srst_asserted(int *srst_asserted)
1711 return jtag->srst_asserted(srst_asserted);
1714 enum reset_types jtag_get_reset_config(void)
1716 return jtag_reset_config;
1718 void jtag_set_reset_config(enum reset_types type)
1720 jtag_reset_config = type;
1723 int jtag_get_trst(void)
1727 int jtag_get_srst(void)
1732 void jtag_set_nsrst_delay(unsigned delay)
1734 adapter_nsrst_delay = delay;
1736 unsigned jtag_get_nsrst_delay(void)
1738 return adapter_nsrst_delay;
1740 void jtag_set_ntrst_delay(unsigned delay)
1742 jtag_ntrst_delay = delay;
1744 unsigned jtag_get_ntrst_delay(void)
1746 return jtag_ntrst_delay;
1750 void jtag_set_nsrst_assert_width(unsigned delay)
1752 adapter_nsrst_assert_width = delay;
1754 unsigned jtag_get_nsrst_assert_width(void)
1756 return adapter_nsrst_assert_width;
1758 void jtag_set_ntrst_assert_width(unsigned delay)
1760 jtag_ntrst_assert_width = delay;
1762 unsigned jtag_get_ntrst_assert_width(void)
1764 return jtag_ntrst_assert_width;
1767 static int jtag_select(struct command_context *ctx)
1771 /* NOTE: interface init must already have been done.
1772 * That works with only C code ... no Tcl glue required.
1775 retval = jtag_register_commands(ctx);
1777 if (retval != ERROR_OK)
1780 retval = svf_register_commands(ctx);
1782 if (retval != ERROR_OK)
1785 return xsvf_register_commands(ctx);
1788 static struct transport jtag_transport = {
1790 .select = jtag_select,
1794 static void jtag_constructor(void) __attribute__((constructor));
1795 static void jtag_constructor(void)
1797 transport_register(&jtag_transport);
1800 /** Returns true if the current debug session
1801 * is using JTAG as its transport.
1803 bool transport_is_jtag(void)
1805 return get_current_transport() == &jtag_transport;