1 /***************************************************************************
2 * Copyright (C) 2005 by Dominic Rath *
3 * Dominic.Rath@gmx.de *
5 * Copyright (C) 2007,2008 Øyvind Harboe *
6 * oyvind.harboe@zylin.com *
8 * This program is free software; you can redistribute it and/or modify *
9 * it under the terms of the GNU General Public License as published by *
10 * the Free Software Foundation; either version 2 of the License, or *
11 * (at your option) any later version. *
13 * This program is distributed in the hope that it will be useful, *
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of *
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
16 * GNU General Public License for more details. *
18 * You should have received a copy of the GNU General Public License *
19 * along with this program; if not, write to the *
20 * Free Software Foundation, Inc., *
21 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *
22 ***************************************************************************/
26 #include "binarybuffer.h"
29 #ifdef _DEBUG_JTAG_IO_
30 #define DEBUG_JTAG_IO(expr ...) \
31 do { if (1) LOG_DEBUG(expr); } while (0)
33 #define DEBUG_JTAG_IO(expr ...) \
34 do { if (0) LOG_DEBUG(expr); } while (0)
37 #ifndef DEBUG_JTAG_IOZ
38 #define DEBUG_JTAG_IOZ 64
41 /*-----<Macros>--------------------------------------------------*/
44 * When given an array, compute its DIMension; in other words, the
45 * number of elements in the array
47 #define DIM(x) (sizeof(x)/sizeof((x)[0]))
49 /** Calculate the number of bytes required to hold @a n TAP scan bits */
50 #define TAP_SCAN_BYTES(n) CEIL(n, 8)
52 /*-----</Macros>-------------------------------------------------*/
55 * Defines JTAG Test Access Port states.
57 * These definitions were gleaned from the ARM7TDMI-S Technical
58 * Reference Manual and validated against several other ARM core
61 * FIXME some interfaces require specific numbers be used, as they
62 * are handed-off directly to their hardware implementations.
63 * Fix those drivers to map as appropriate ... then pick some
64 * sane set of numbers here (where 0/uninitialized == INVALID).
66 typedef enum tap_state
71 /* These are the old numbers. Leave as-is for now... */
72 TAP_RESET = 0, TAP_IDLE = 8,
73 TAP_DRSELECT = 1, TAP_DRCAPTURE = 2, TAP_DRSHIFT = 3, TAP_DREXIT1 = 4,
74 TAP_DRPAUSE = 5, TAP_DREXIT2 = 6, TAP_DRUPDATE = 7,
75 TAP_IRSELECT = 9, TAP_IRCAPTURE = 10, TAP_IRSHIFT = 11, TAP_IREXIT1 = 12,
76 TAP_IRPAUSE = 13, TAP_IREXIT2 = 14, TAP_IRUPDATE = 15,
79 /* Proper ARM recommended numbers */
101 * Function tap_state_name
102 * Returns a string suitable for display representing the JTAG tap_state
104 const char *tap_state_name(tap_state_t state);
106 /// Provides user-friendly name lookup of TAP states.
107 tap_state_t tap_state_by_name(const char *name);
109 /// The current TAP state of the pending JTAG command queue.
110 extern tap_state_t cmd_queue_cur_state;
113 * This structure defines a single scan field in the scan. It provides
114 * fields for the field's width and pointers to scan input and output
117 * In addition, this structure includes a value and mask that is used by
118 * jtag_add_dr_scan_check() to validate the value that was scanned out.
120 * The allocated, modified, and intmp fields are internal work space.
123 /// A pointer to the tap structure to which this field refers.
124 struct jtag_tap* tap;
126 /// The number of bits this field specifies (up to 32)
128 /// A pointer to value to be scanned into the device
130 /// A pointer to a 32-bit memory location for data scanned out
133 /// The value used to check the data scanned out.
134 uint8_t* check_value;
135 /// The mask to go with check_value
138 /// in_value has been allocated for the queue
140 /// Indicates we modified the in_value.
142 /// temporary storage for performing value checks synchronously
149 const char* dotted_name;
150 int abs_chain_position;
151 /// Is this TAP disabled after JTAG reset?
152 bool disabled_after_reset;
153 /// Is this TAP currently enabled?
155 int ir_length; /**< size of instruction register */
156 uint32_t ir_capture_value;
157 uint8_t* expected; /**< Capture-IR expected value */
158 uint32_t ir_capture_mask;
159 uint8_t* expected_mask; /**< Capture-IR expected mask */
160 uint32_t idcode; /**< device identification code */
161 /** not all devices have idcode,
162 * we'll discover this during chain examination */
165 /// Array of expected identification codes */
166 uint32_t* expected_ids;
167 /// Number of expected identification codes
168 uint8_t expected_ids_cnt;
170 /// current instruction
172 /// Bypass register selected
175 struct jtag_tap_event_action *event_action;
177 struct jtag_tap* next_tap;
180 void jtag_tap_init(struct jtag_tap *tap);
181 void jtag_tap_free(struct jtag_tap *tap);
183 struct jtag_tap* jtag_all_taps(void);
184 const char *jtag_tap_name(const struct jtag_tap *tap);
185 struct jtag_tap* jtag_tap_by_string(const char* dotted_name);
186 struct jtag_tap* jtag_tap_by_jim_obj(Jim_Interp* interp, Jim_Obj* obj);
187 struct jtag_tap* jtag_tap_next_enabled(struct jtag_tap* p);
188 unsigned jtag_tap_count_enabled(void);
189 unsigned jtag_tap_count(void);
193 * - TRST_ASSERTED triggers two sets of callbacks, after operations to
194 * reset the scan chain -- via TMS+TCK signaling, or deasserting the
195 * nTRST signal -- are queued:
197 * + Callbacks in C code fire first, patching internal state
198 * + Then post-reset event scripts fire ... activating JTAG circuits
199 * via TCK cycles, exiting SWD mode via TMS sequences, etc
201 * During those callbacks, scan chain contents have not been validated.
202 * JTAG operations that address a specific TAP (primarily DR/IR scans)
203 * must *not* be queued.
205 * - TAP_EVENT_SETUP is reported after TRST_ASSERTED, and after the scan
206 * chain has been validated. JTAG operations including scans that
207 * target specific TAPs may be performed.
209 * - TAP_EVENT_ENABLE and TAP_EVENT_DISABLE implement TAP activation and
210 * deactivation outside the core using scripted code that understands
211 * the specific JTAG router type. They might be triggered indirectly
212 * from EVENT_SETUP operations.
216 JTAG_TAP_EVENT_SETUP,
217 JTAG_TAP_EVENT_ENABLE,
218 JTAG_TAP_EVENT_DISABLE,
221 struct jtag_tap_event_action
223 enum jtag_event event;
225 struct jtag_tap_event_action* next;
229 * Defines the function signature requide for JTAG event callback
230 * functions, which are added with jtag_register_event_callback()
231 * and removed jtag_unregister_event_callback().
232 * @param event The event to handle.
233 * @param prive A pointer to data that was passed to
234 * jtag_register_event_callback().
235 * @returns Must return ERROR_OK on success, or an error code on failure.
237 * @todo Change to return void or define a use for its return code.
239 typedef int (*jtag_event_handler_t)(enum jtag_event event, void* priv);
241 int jtag_register_event_callback(jtag_event_handler_t f, void *x);
242 int jtag_unregister_event_callback(jtag_event_handler_t f, void *x);
244 int jtag_call_event_callbacks(enum jtag_event event);
247 /// @returns The current JTAG speed setting.
248 int jtag_get_speed(void);
251 * Given a @a speed setting, use the interface @c speed_div callback to
252 * adjust the setting.
253 * @param speed The speed setting to convert back to readable KHz.
254 * @returns ERROR_OK if the interface has not been initialized or on success;
255 * otherwise, the error code produced by the @c speed_div callback.
257 int jtag_get_speed_readable(int *speed);
259 /// Attempt to configure the interface for the specified KHz.
260 int jtag_config_khz(unsigned khz);
263 * Attempt to enable RTCK/RCLK. If that fails, fallback to the
264 * specified frequency.
266 int jtag_config_rclk(unsigned fallback_speed_khz);
268 /// Retreives the clock speed of the JTAG interface in KHz.
269 unsigned jtag_get_speed_khz(void);
274 RESET_HAS_TRST = 0x1,
275 RESET_HAS_SRST = 0x2,
276 RESET_TRST_AND_SRST = 0x3,
277 RESET_SRST_PULLS_TRST = 0x4,
278 RESET_TRST_PULLS_SRST = 0x8,
279 RESET_TRST_OPEN_DRAIN = 0x10,
280 RESET_SRST_PUSH_PULL = 0x20,
281 RESET_SRST_NO_GATING = 0x40,
284 enum reset_types jtag_get_reset_config(void);
285 void jtag_set_reset_config(enum reset_types type);
287 void jtag_set_nsrst_delay(unsigned delay);
288 unsigned jtag_get_nsrst_delay(void);
290 void jtag_set_ntrst_delay(unsigned delay);
291 unsigned jtag_get_ntrst_delay(void);
293 void jtag_set_nsrst_assert_width(unsigned delay);
294 unsigned jtag_get_nsrst_assert_width(void);
296 void jtag_set_ntrst_assert_width(unsigned delay);
297 unsigned jtag_get_ntrst_assert_width(void);
299 /// @returns The current state of TRST.
300 int jtag_get_trst(void);
301 /// @returns The current state of SRST.
302 int jtag_get_srst(void);
304 /// Enable or disable data scan verification checking.
305 void jtag_set_verify(bool enable);
306 /// @returns True if data scan verification will be performed.
307 bool jtag_will_verify(void);
309 /// Enable or disable verification of IR scan checking.
310 void jtag_set_verify_capture_ir(bool enable);
311 /// @returns True if IR scan verification will be performed.
312 bool jtag_will_verify_capture_ir(void);
315 * Initialize interface upon startup. Return a successful no-op upon
316 * subsequent invocations.
318 int jtag_interface_init(struct command_context_s* cmd_ctx);
320 /// Shutdown the JTAG interface upon program exit.
321 int jtag_interface_quit(void);
324 * Initialize JTAG chain using only a RESET reset. If init fails,
327 int jtag_init(struct command_context_s* cmd_ctx);
329 /// reset, then initialize JTAG chain
330 int jtag_init_reset(struct command_context_s* cmd_ctx);
331 int jtag_register_commands(struct command_context_s* cmd_ctx);
332 int jtag_init_inner(struct command_context_s *cmd_ctx);
336 * The JTAG interface can be implemented with a software or hardware fifo.
338 * TAP_DRSHIFT and TAP_IRSHIFT are illegal end states; however,
339 * TAP_DRSHIFT/IRSHIFT can be emulated as end states, by using longer
342 * Code that is relatively insensitive to the path taken through state
343 * machine (as long as it is JTAG compliant) can use @a endstate for
344 * jtag_add_xxx_scan(). Otherwise, the pause state must be specified as
345 * end state and a subsequent jtag_add_pathmove() must be issued.
349 * Generate an IR SCAN with a list of scan fields with one entry for
352 * If the input field list contains an instruction value for a TAP then
353 * that is used otherwise the TAP is set to bypass.
355 * TAPs for which no fields are passed are marked as bypassed for
356 * subsequent DR SCANs.
359 void jtag_add_ir_scan(int num_fields,
360 struct scan_field* fields, tap_state_t endstate);
362 * The same as jtag_add_ir_scan except no verification is performed out
365 void jtag_add_ir_scan_noverify(int num_fields,
366 const struct scan_field *fields, tap_state_t state);
368 * Duplicate the scan fields passed into the function into an IR SCAN
369 * command. This function assumes that the caller handles extra fields
372 void jtag_add_plain_ir_scan(int num_fields,
373 const struct scan_field* fields, tap_state_t endstate);
377 * Set in_value to point to 32 bits of memory to scan into. This
378 * function is a way to handle the case of synchronous and asynchronous
381 * In the event of an asynchronous queue execution the queue buffer
382 * allocation method is used, for the synchronous case the temporary 32
383 * bits come from the input field itself.
385 void jtag_alloc_in_value32(struct scan_field *field);
388 * Generate a DR SCAN using the fields passed to the function.
389 * For connected TAPs, the function checks in_fields and uses fields
390 * specified there. For bypassed TAPs, the function generates a dummy
391 * 1-bit field. The bypass status of TAPs is set by jtag_add_ir_scan().
393 void jtag_add_dr_scan(int num_fields,
394 const struct scan_field* fields, tap_state_t endstate);
395 /// A version of jtag_add_dr_scan() that uses the check_value/mask fields
396 void jtag_add_dr_scan_check(int num_fields,
397 struct scan_field* fields, tap_state_t endstate);
399 * Duplicate the scan fields passed into the function into a DR SCAN
400 * command. Unlike jtag_add_dr_scan(), this function assumes that the
401 * caller handles extra fields for bypassed TAPs.
403 void jtag_add_plain_dr_scan(int num_fields,
404 const struct scan_field* fields, tap_state_t endstate);
407 * Defines the type of data passed to the jtag_callback_t interface.
408 * The underlying type must allow storing an @c int or pointer type.
410 typedef intptr_t jtag_callback_data_t;
413 * Defines a simple JTAG callback that can allow conversions on data
414 * scanned in from an interface.
416 * This callback should only be used for conversion that cannot fail.
417 * For conversion types or checks that can fail, use the more complete
418 * variant: jtag_callback_t.
420 typedef void (*jtag_callback1_t)(jtag_callback_data_t data0);
422 /// A simpler version of jtag_add_callback4().
423 void jtag_add_callback(jtag_callback1_t, jtag_callback_data_t data0);
428 * Defines the interface of the JTAG callback mechanism.
430 * @param in the pointer to the data clocked in
431 * @param data1 An integer big enough to use as an @c int or a pointer.
432 * @param data2 An integer big enough to use as an @c int or a pointer.
433 * @param data3 An integer big enough to use as an @c int or a pointer.
434 * @returns an error code
436 typedef int (*jtag_callback_t)(jtag_callback_data_t data0,
437 jtag_callback_data_t data1,
438 jtag_callback_data_t data2,
439 jtag_callback_data_t data3);
443 * This callback can be executed immediately the queue has been flushed.
445 * The JTAG queue can be executed synchronously or asynchronously.
446 * Typically for USB, the queue is executed asynchronously. For
447 * low-latency interfaces, the queue may be executed synchronously.
449 * The callback mechanism is very general and does not make many
450 * assumptions about what the callback does or what its arguments are.
451 * These callbacks are typically executed *after* the *entire* JTAG
452 * queue has been executed for e.g. USB interfaces, and they are
453 * guaranteeed to be invoked in the order that they were queued.
455 * If the execution of the queue fails before the callbacks, then --
456 * depending on driver implementation -- the callbacks may or may not be
457 * invoked. @todo Can we make this behavior consistent?
459 * The strange name is due to C's lack of overloading using function
462 * @param f The callback function to add.
463 * @param data0 Typically used to point to the data to operate on.
464 * Frequently this will be the data clocked in during a shift operation.
465 * @param data1 An integer big enough to use as an @c int or a pointer.
466 * @param data2 An integer big enough to use as an @c int or a pointer.
467 * @param data3 An integer big enough to use as an @c int or a pointer.
470 void jtag_add_callback4(jtag_callback_t f, jtag_callback_data_t data0,
471 jtag_callback_data_t data1, jtag_callback_data_t data2,
472 jtag_callback_data_t data3);
476 * Run a TAP_RESET reset where the end state is TAP_RESET,
477 * regardless of the start state.
479 void jtag_add_tlr(void);
482 * Application code *must* assume that interfaces will
483 * implement transitions between states with different
484 * paths and path lengths through the state diagram. The
485 * path will vary across interface and also across versions
486 * of the same interface over time. Even if the OpenOCD code
487 * is unchanged, the actual path taken may vary over time
488 * and versions of interface firmware or PCB revisions.
490 * Use jtag_add_pathmove() when specific transition sequences
493 * Do not use jtag_add_pathmove() unless you need to, but do use it
496 * DANGER! If the target is dependent upon a particular sequence
497 * of transitions for things to work correctly(e.g. as a workaround
498 * for an errata that contradicts the JTAG standard), then pathmove
499 * must be used, even if some jtag interfaces happen to use the
500 * desired path. Worse, the jtag interface used for testing a
501 * particular implementation, could happen to use the "desired"
502 * path when transitioning to/from end
505 * A list of unambigious single clock state transitions, not
506 * all drivers can support this, but it is required for e.g.
507 * XScale and Xilinx support
509 * Note! TAP_RESET must not be used in the path!
511 * Note that the first on the list must be reachable
512 * via a single transition from the current state.
514 * All drivers are required to implement jtag_add_pathmove().
515 * However, if the pathmove sequence can not be precisely
516 * executed, an interface_jtag_add_pathmove() or jtag_execute_queue()
517 * must return an error. It is legal, but not recommended, that
518 * a driver returns an error in all cases for a pathmove if it
519 * can only implement a few transitions and therefore
520 * a partial implementation of pathmove would have little practical
523 * If an error occurs, jtag_error will contain one of these error codes:
524 * - ERROR_JTAG_NOT_STABLE_STATE -- The final state was not stable.
525 * - ERROR_JTAG_STATE_INVALID -- The path passed through TAP_RESET.
526 * - ERROR_JTAG_TRANSITION_INVALID -- The path includes invalid
529 void jtag_add_pathmove(int num_states, const tap_state_t* path);
532 * jtag_add_statemove() moves from the current state to @a goal_state.
534 * @param goal_state The final TAP state.
535 * @return ERROR_OK on success, or an error code on failure.
537 * Moves from the current state to the goal \a state.
538 * Both states must be stable.
540 int jtag_add_statemove(tap_state_t goal_state);
543 * Goes to TAP_IDLE (if we're not already there), cycle
544 * precisely num_cycles in the TAP_IDLE state, after which move
545 * to @a endstate (unless it is also TAP_IDLE).
547 * @param num_cycles Number of cycles in TAP_IDLE state. This argument
548 * may be 0, in which case this routine will navigate to @a endstate
550 * @param endstate The final state.
552 void jtag_add_runtest(int num_cycles, tap_state_t endstate);
555 * A reset of the TAP state machine can be requested.
557 * Whether tms or trst reset is used depends on the capabilities of
558 * the target and jtag interface(reset_config command configures this).
560 * srst can driver a reset of the TAP state machine and vice
563 * Application code may need to examine value of jtag_reset_config
564 * to determine the proper codepath
566 * DANGER! Even though srst drives trst, trst might not be connected to
567 * the interface, and it might actually be *harmful* to assert trst in this case.
569 * This is why combinations such as "reset_config srst_only srst_pulls_trst"
572 * only req_tlr_or_trst and srst can have a transition for a
573 * call as the effects of transitioning both at the "same time"
574 * are undefined, but when srst_pulls_trst or vice versa,
575 * then trst & srst *must* be asserted together.
577 void jtag_add_reset(int req_tlr_or_trst, int srst);
581 * Function jtag_set_end_state
583 * Set a global variable to \a state if \a state != TAP_INVALID.
585 * Return the value of the global variable.
588 tap_state_t jtag_set_end_state(tap_state_t state);
590 * Function jtag_get_end_state
592 * Return the value of the global variable for end state
595 tap_state_t jtag_get_end_state(void);
596 void jtag_add_sleep(uint32_t us);
600 * Function jtag_add_stable_clocks
601 * first checks that the state in which the clocks are to be issued is
602 * stable, then queues up clock_count clocks for transmission.
604 void jtag_add_clocks(int num_cycles);
608 * For software FIFO implementations, the queued commands can be executed
609 * during this call or earlier. A sw queue might decide to push out
610 * some of the jtag_add_xxx() operations once the queue is "big enough".
612 * This fn will return an error code if any of the prior jtag_add_xxx()
613 * calls caused a failure, e.g. check failure. Note that it does not
614 * matter if the operation was executed *before* jtag_execute_queue(),
615 * jtag_execute_queue() will still return an error code.
617 * All jtag_add_xxx() calls that have in_handler != NULL will have been
618 * executed when this fn returns, but if what has been queued only
619 * clocks data out, without reading anything back, then JTAG could
620 * be running *after* jtag_execute_queue() returns. The API does
621 * not define a way to flush a hw FIFO that runs *after*
622 * jtag_execute_queue() returns.
624 * jtag_add_xxx() commands can either be executed immediately or
625 * at some time between the jtag_add_xxx() fn call and jtag_execute_queue().
627 int jtag_execute_queue(void);
629 /// same as jtag_execute_queue() but does not clear the error flag
630 void jtag_execute_queue_noclear(void);
632 /// @returns the number of times the scan queue has been flushed
633 int jtag_get_flush_queue_count(void);
635 /// Report Tcl event to all TAPs
636 void jtag_notify_event(enum jtag_event);
639 /* can be implemented by hw + sw */
640 int jtag_power_dropout(int* dropout);
641 int jtag_srst_asserted(int* srst_asserted);
643 /* JTAG support functions */
646 * Execute jtag queue and check value with an optional mask.
647 * @param field Pointer to scan field.
648 * @param value Pointer to scan value.
649 * @param mask Pointer to scan mask; may be NULL.
650 * @returns Nothing, but calls jtag_set_error() on any error.
652 void jtag_check_value_mask(struct scan_field *field, uint8_t *value, uint8_t *mask);
654 void jtag_sleep(uint32_t us);
657 * The JTAG subsystem defines a number of error codes,
658 * using codes between -100 and -199.
660 #define ERROR_JTAG_INIT_FAILED (-100)
661 #define ERROR_JTAG_INVALID_INTERFACE (-101)
662 #define ERROR_JTAG_NOT_IMPLEMENTED (-102)
663 #define ERROR_JTAG_TRST_ASSERTED (-103)
664 #define ERROR_JTAG_QUEUE_FAILED (-104)
665 #define ERROR_JTAG_NOT_STABLE_STATE (-105)
666 #define ERROR_JTAG_DEVICE_ERROR (-107)
667 #define ERROR_JTAG_STATE_INVALID (-108)
668 #define ERROR_JTAG_TRANSITION_INVALID (-109)
669 #define ERROR_JTAG_INIT_SOFT_FAIL (-110)
672 * jtag_add_dr_out() is a version of jtag_add_dr_scan() which
673 * only scans data out. It operates on 32 bit integers instead
674 * of 8 bit, which makes it a better impedance match with
675 * the calling code which often operate on 32 bit integers.
677 * Current or end_state can not be TAP_RESET. end_state can be TAP_INVALID
679 * num_bits[i] is the number of bits to clock out from value[i] LSB first.
681 * If the device is in bypass, then that is an error condition in
682 * the caller code that is not detected by this fn, whereas
683 * jtag_add_dr_scan() does detect it. Similarly if the device is not in
684 * bypass, data must be passed to it.
686 * If anything fails, then jtag_error will be set and jtag_execute() will
687 * return an error. There is no way to determine if there was a failure
688 * during this function call.
690 * This is an inline fn to speed up embedded hosts. Also note that
691 * interface_jtag_add_dr_out() can be a *small* inline function for
694 * There is no jtag_add_dr_outin() version of this fn that also allows
695 * clocking data back in. Patches gladly accepted!
697 void jtag_add_dr_out(struct jtag_tap* tap,
698 int num_fields, const int* num_bits, const uint32_t* value,
699 tap_state_t end_state);
703 * Set the current JTAG core execution error, unless one was set
704 * by a previous call previously. Driver or application code must
705 * use jtag_error_clear to reset jtag_error once this routine has been
706 * called with a non-zero error code.
708 void jtag_set_error(int error);
709 /// @returns The current value of jtag_error
710 int jtag_get_error(void);
712 * Resets jtag_error to ERROR_OK, returning its previous value.
713 * @returns The previous value of @c jtag_error.
715 int jtag_error_clear(void);
718 * Return true if it's safe for a background polling task to access the
719 * JTAG scan chain. Polling may be explicitly disallowed, and is also
720 * unsafe while nTRST is active or the JTAG clock is gated off.,
722 bool is_jtag_poll_safe(void);
725 * Return flag reporting whether JTAG polling is disallowed.
727 bool jtag_poll_get_enabled(void);
730 * Assign flag reporting whether JTAG polling is disallowed.
732 void jtag_poll_set_enabled(bool value);