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 * Defines JTAG Test Access Port states.
46 * These definitions were gleaned from the ARM7TDMI-S Technical
47 * Reference Manual and validated against several other ARM core
50 * FIXME some interfaces require specific numbers be used, as they
51 * are handed-off directly to their hardware implementations.
52 * Fix those drivers to map as appropriate ... then pick some
53 * sane set of numbers here (where 0/uninitialized == INVALID).
55 typedef enum tap_state
60 /* These are the old numbers. Leave as-is for now... */
61 TAP_RESET = 0, TAP_IDLE = 8,
62 TAP_DRSELECT = 1, TAP_DRCAPTURE = 2, TAP_DRSHIFT = 3, TAP_DREXIT1 = 4,
63 TAP_DRPAUSE = 5, TAP_DREXIT2 = 6, TAP_DRUPDATE = 7,
64 TAP_IRSELECT = 9, TAP_IRCAPTURE = 10, TAP_IRSHIFT = 11, TAP_IREXIT1 = 12,
65 TAP_IRPAUSE = 13, TAP_IREXIT2 = 14, TAP_IRUPDATE = 15,
68 /* Proper ARM recommended numbers */
90 * Function tap_state_name
91 * Returns a string suitable for display representing the JTAG tap_state
93 const char *tap_state_name(tap_state_t state);
95 /// Provides user-friendly name lookup of TAP states.
96 tap_state_t tap_state_by_name(const char *name);
98 /// The current TAP state of the pending JTAG command queue.
99 extern tap_state_t cmd_queue_cur_state;
102 * This structure defines a single scan field in the scan. It provides
103 * fields for the field's width and pointers to scan input and output
106 * In addition, this structure includes a value and mask that is used by
107 * jtag_add_dr_scan_check() to validate the value that was scanned out.
109 * The allocated, modified, and intmp fields are internal work space.
112 /// A pointer to the tap structure to which this field refers.
113 struct jtag_tap* tap;
115 /// The number of bits this field specifies (up to 32)
117 /// A pointer to value to be scanned into the device
119 /// A pointer to a 32-bit memory location for data scanned out
122 /// The value used to check the data scanned out.
123 uint8_t* check_value;
124 /// The mask to go with check_value
127 /// in_value has been allocated for the queue
129 /// Indicates we modified the in_value.
131 /// temporary storage for performing value checks synchronously
138 const char* dotted_name;
139 int abs_chain_position;
140 /// Is this TAP disabled after JTAG reset?
141 bool disabled_after_reset;
142 /// Is this TAP currently enabled?
144 int ir_length; /**< size of instruction register */
145 uint32_t ir_capture_value;
146 uint8_t* expected; /**< Capture-IR expected value */
147 uint32_t ir_capture_mask;
148 uint8_t* expected_mask; /**< Capture-IR expected mask */
149 uint32_t idcode; /**< device identification code */
150 /** not all devices have idcode,
151 * we'll discover this during chain examination */
154 /// Array of expected identification codes */
155 uint32_t* expected_ids;
156 /// Number of expected identification codes
157 uint8_t expected_ids_cnt;
159 /// current instruction
161 /// Bypass register selected
164 struct jtag_tap_event_action *event_action;
166 struct jtag_tap* next_tap;
169 void jtag_tap_init(struct jtag_tap *tap);
170 void jtag_tap_free(struct jtag_tap *tap);
172 struct jtag_tap* jtag_all_taps(void);
173 const char *jtag_tap_name(const struct jtag_tap *tap);
174 struct jtag_tap* jtag_tap_by_string(const char* dotted_name);
175 struct jtag_tap* jtag_tap_by_jim_obj(Jim_Interp* interp, Jim_Obj* obj);
176 struct jtag_tap* jtag_tap_next_enabled(struct jtag_tap* p);
177 unsigned jtag_tap_count_enabled(void);
178 unsigned jtag_tap_count(void);
182 * - TRST_ASSERTED triggers two sets of callbacks, after operations to
183 * reset the scan chain -- via TMS+TCK signaling, or deasserting the
184 * nTRST signal -- are queued:
186 * + Callbacks in C code fire first, patching internal state
187 * + Then post-reset event scripts fire ... activating JTAG circuits
188 * via TCK cycles, exiting SWD mode via TMS sequences, etc
190 * During those callbacks, scan chain contents have not been validated.
191 * JTAG operations that address a specific TAP (primarily DR/IR scans)
192 * must *not* be queued.
194 * - TAP_EVENT_SETUP is reported after TRST_ASSERTED, and after the scan
195 * chain has been validated. JTAG operations including scans that
196 * target specific TAPs may be performed.
198 * - TAP_EVENT_ENABLE and TAP_EVENT_DISABLE implement TAP activation and
199 * deactivation outside the core using scripted code that understands
200 * the specific JTAG router type. They might be triggered indirectly
201 * from EVENT_SETUP operations.
205 JTAG_TAP_EVENT_SETUP,
206 JTAG_TAP_EVENT_ENABLE,
207 JTAG_TAP_EVENT_DISABLE,
210 struct jtag_tap_event_action
212 enum jtag_event event;
214 struct jtag_tap_event_action* next;
218 * Defines the function signature requide for JTAG event callback
219 * functions, which are added with jtag_register_event_callback()
220 * and removed jtag_unregister_event_callback().
221 * @param event The event to handle.
222 * @param prive A pointer to data that was passed to
223 * jtag_register_event_callback().
224 * @returns Must return ERROR_OK on success, or an error code on failure.
226 * @todo Change to return void or define a use for its return code.
228 typedef int (*jtag_event_handler_t)(enum jtag_event event, void* priv);
230 int jtag_register_event_callback(jtag_event_handler_t f, void *x);
231 int jtag_unregister_event_callback(jtag_event_handler_t f, void *x);
233 int jtag_call_event_callbacks(enum jtag_event event);
236 /// @returns The current JTAG speed setting.
237 int jtag_get_speed(void);
240 * Given a @a speed setting, use the interface @c speed_div callback to
241 * adjust the setting.
242 * @param speed The speed setting to convert back to readable KHz.
243 * @returns ERROR_OK if the interface has not been initialized or on success;
244 * otherwise, the error code produced by the @c speed_div callback.
246 int jtag_get_speed_readable(int *speed);
248 /// Attempt to configure the interface for the specified KHz.
249 int jtag_config_khz(unsigned khz);
252 * Attempt to enable RTCK/RCLK. If that fails, fallback to the
253 * specified frequency.
255 int jtag_config_rclk(unsigned fallback_speed_khz);
257 /// Retreives the clock speed of the JTAG interface in KHz.
258 unsigned jtag_get_speed_khz(void);
263 RESET_HAS_TRST = 0x1,
264 RESET_HAS_SRST = 0x2,
265 RESET_TRST_AND_SRST = 0x3,
266 RESET_SRST_PULLS_TRST = 0x4,
267 RESET_TRST_PULLS_SRST = 0x8,
268 RESET_TRST_OPEN_DRAIN = 0x10,
269 RESET_SRST_PUSH_PULL = 0x20,
270 RESET_SRST_NO_GATING = 0x40,
273 enum reset_types jtag_get_reset_config(void);
274 void jtag_set_reset_config(enum reset_types type);
276 void jtag_set_nsrst_delay(unsigned delay);
277 unsigned jtag_get_nsrst_delay(void);
279 void jtag_set_ntrst_delay(unsigned delay);
280 unsigned jtag_get_ntrst_delay(void);
282 void jtag_set_nsrst_assert_width(unsigned delay);
283 unsigned jtag_get_nsrst_assert_width(void);
285 void jtag_set_ntrst_assert_width(unsigned delay);
286 unsigned jtag_get_ntrst_assert_width(void);
288 /// @returns The current state of TRST.
289 int jtag_get_trst(void);
290 /// @returns The current state of SRST.
291 int jtag_get_srst(void);
293 /// Enable or disable data scan verification checking.
294 void jtag_set_verify(bool enable);
295 /// @returns True if data scan verification will be performed.
296 bool jtag_will_verify(void);
298 /// Enable or disable verification of IR scan checking.
299 void jtag_set_verify_capture_ir(bool enable);
300 /// @returns True if IR scan verification will be performed.
301 bool jtag_will_verify_capture_ir(void);
304 * Initialize interface upon startup. Return a successful no-op upon
305 * subsequent invocations.
307 int jtag_interface_init(struct command_context* cmd_ctx);
309 /// Shutdown the JTAG interface upon program exit.
310 int jtag_interface_quit(void);
313 * Initialize JTAG chain using only a RESET reset. If init fails,
316 int jtag_init(struct command_context* cmd_ctx);
318 /// reset, then initialize JTAG chain
319 int jtag_init_reset(struct command_context* cmd_ctx);
320 int jtag_register_commands(struct command_context* cmd_ctx);
321 int jtag_init_inner(struct command_context *cmd_ctx);
325 * The JTAG interface can be implemented with a software or hardware fifo.
327 * TAP_DRSHIFT and TAP_IRSHIFT are illegal end states; however,
328 * TAP_DRSHIFT/IRSHIFT can be emulated as end states, by using longer
331 * Code that is relatively insensitive to the path taken through state
332 * machine (as long as it is JTAG compliant) can use @a endstate for
333 * jtag_add_xxx_scan(). Otherwise, the pause state must be specified as
334 * end state and a subsequent jtag_add_pathmove() must be issued.
338 * Generate an IR SCAN with a list of scan fields with one entry for
341 * If the input field list contains an instruction value for a TAP then
342 * that is used otherwise the TAP is set to bypass.
344 * TAPs for which no fields are passed are marked as bypassed for
345 * subsequent DR SCANs.
348 void jtag_add_ir_scan(int num_fields,
349 struct scan_field* fields, tap_state_t endstate);
351 * The same as jtag_add_ir_scan except no verification is performed out
354 void jtag_add_ir_scan_noverify(int num_fields,
355 const struct scan_field *fields, tap_state_t state);
357 * Duplicate the scan fields passed into the function into an IR SCAN
358 * command. This function assumes that the caller handles extra fields
361 void jtag_add_plain_ir_scan(int num_fields,
362 const struct scan_field* fields, tap_state_t endstate);
366 * Set in_value to point to 32 bits of memory to scan into. This
367 * function is a way to handle the case of synchronous and asynchronous
370 * In the event of an asynchronous queue execution the queue buffer
371 * allocation method is used, for the synchronous case the temporary 32
372 * bits come from the input field itself.
374 void jtag_alloc_in_value32(struct scan_field *field);
377 * Generate a DR SCAN using the fields passed to the function.
378 * For connected TAPs, the function checks in_fields and uses fields
379 * specified there. For bypassed TAPs, the function generates a dummy
380 * 1-bit field. The bypass status of TAPs is set by jtag_add_ir_scan().
382 void jtag_add_dr_scan(int num_fields,
383 const struct scan_field* fields, tap_state_t endstate);
384 /// A version of jtag_add_dr_scan() that uses the check_value/mask fields
385 void jtag_add_dr_scan_check(int num_fields,
386 struct scan_field* fields, tap_state_t endstate);
388 * Duplicate the scan fields passed into the function into a DR SCAN
389 * command. Unlike jtag_add_dr_scan(), this function assumes that the
390 * caller handles extra fields for bypassed TAPs.
392 void jtag_add_plain_dr_scan(int num_fields,
393 const struct scan_field* fields, tap_state_t endstate);
396 * Defines the type of data passed to the jtag_callback_t interface.
397 * The underlying type must allow storing an @c int or pointer type.
399 typedef intptr_t jtag_callback_data_t;
402 * Defines a simple JTAG callback that can allow conversions on data
403 * scanned in from an interface.
405 * This callback should only be used for conversion that cannot fail.
406 * For conversion types or checks that can fail, use the more complete
407 * variant: jtag_callback_t.
409 typedef void (*jtag_callback1_t)(jtag_callback_data_t data0);
411 /// A simpler version of jtag_add_callback4().
412 void jtag_add_callback(jtag_callback1_t, jtag_callback_data_t data0);
417 * Defines the interface of the JTAG callback mechanism.
419 * @param in the pointer to the data clocked in
420 * @param data1 An integer big enough to use as an @c int or a pointer.
421 * @param data2 An integer big enough to use as an @c int or a pointer.
422 * @param data3 An integer big enough to use as an @c int or a pointer.
423 * @returns an error code
425 typedef int (*jtag_callback_t)(jtag_callback_data_t data0,
426 jtag_callback_data_t data1,
427 jtag_callback_data_t data2,
428 jtag_callback_data_t data3);
432 * This callback can be executed immediately the queue has been flushed.
434 * The JTAG queue can be executed synchronously or asynchronously.
435 * Typically for USB, the queue is executed asynchronously. For
436 * low-latency interfaces, the queue may be executed synchronously.
438 * The callback mechanism is very general and does not make many
439 * assumptions about what the callback does or what its arguments are.
440 * These callbacks are typically executed *after* the *entire* JTAG
441 * queue has been executed for e.g. USB interfaces, and they are
442 * guaranteeed to be invoked in the order that they were queued.
444 * If the execution of the queue fails before the callbacks, then --
445 * depending on driver implementation -- the callbacks may or may not be
446 * invoked. @todo Can we make this behavior consistent?
448 * The strange name is due to C's lack of overloading using function
451 * @param f The callback function to add.
452 * @param data0 Typically used to point to the data to operate on.
453 * Frequently this will be the data clocked in during a shift operation.
454 * @param data1 An integer big enough to use as an @c int or a pointer.
455 * @param data2 An integer big enough to use as an @c int or a pointer.
456 * @param data3 An integer big enough to use as an @c int or a pointer.
459 void jtag_add_callback4(jtag_callback_t f, jtag_callback_data_t data0,
460 jtag_callback_data_t data1, jtag_callback_data_t data2,
461 jtag_callback_data_t data3);
465 * Run a TAP_RESET reset where the end state is TAP_RESET,
466 * regardless of the start state.
468 void jtag_add_tlr(void);
471 * Application code *must* assume that interfaces will
472 * implement transitions between states with different
473 * paths and path lengths through the state diagram. The
474 * path will vary across interface and also across versions
475 * of the same interface over time. Even if the OpenOCD code
476 * is unchanged, the actual path taken may vary over time
477 * and versions of interface firmware or PCB revisions.
479 * Use jtag_add_pathmove() when specific transition sequences
482 * Do not use jtag_add_pathmove() unless you need to, but do use it
485 * DANGER! If the target is dependent upon a particular sequence
486 * of transitions for things to work correctly(e.g. as a workaround
487 * for an errata that contradicts the JTAG standard), then pathmove
488 * must be used, even if some jtag interfaces happen to use the
489 * desired path. Worse, the jtag interface used for testing a
490 * particular implementation, could happen to use the "desired"
491 * path when transitioning to/from end
494 * A list of unambigious single clock state transitions, not
495 * all drivers can support this, but it is required for e.g.
496 * XScale and Xilinx support
498 * Note! TAP_RESET must not be used in the path!
500 * Note that the first on the list must be reachable
501 * via a single transition from the current state.
503 * All drivers are required to implement jtag_add_pathmove().
504 * However, if the pathmove sequence can not be precisely
505 * executed, an interface_jtag_add_pathmove() or jtag_execute_queue()
506 * must return an error. It is legal, but not recommended, that
507 * a driver returns an error in all cases for a pathmove if it
508 * can only implement a few transitions and therefore
509 * a partial implementation of pathmove would have little practical
512 * If an error occurs, jtag_error will contain one of these error codes:
513 * - ERROR_JTAG_NOT_STABLE_STATE -- The final state was not stable.
514 * - ERROR_JTAG_STATE_INVALID -- The path passed through TAP_RESET.
515 * - ERROR_JTAG_TRANSITION_INVALID -- The path includes invalid
518 void jtag_add_pathmove(int num_states, const tap_state_t* path);
521 * jtag_add_statemove() moves from the current state to @a goal_state.
523 * @param goal_state The final TAP state.
524 * @return ERROR_OK on success, or an error code on failure.
526 * Moves from the current state to the goal \a state.
527 * Both states must be stable.
529 int jtag_add_statemove(tap_state_t goal_state);
532 * Goes to TAP_IDLE (if we're not already there), cycle
533 * precisely num_cycles in the TAP_IDLE state, after which move
534 * to @a endstate (unless it is also TAP_IDLE).
536 * @param num_cycles Number of cycles in TAP_IDLE state. This argument
537 * may be 0, in which case this routine will navigate to @a endstate
539 * @param endstate The final state.
541 void jtag_add_runtest(int num_cycles, tap_state_t endstate);
544 * A reset of the TAP state machine can be requested.
546 * Whether tms or trst reset is used depends on the capabilities of
547 * the target and jtag interface(reset_config command configures this).
549 * srst can driver a reset of the TAP state machine and vice
552 * Application code may need to examine value of jtag_reset_config
553 * to determine the proper codepath
555 * DANGER! Even though srst drives trst, trst might not be connected to
556 * the interface, and it might actually be *harmful* to assert trst in this case.
558 * This is why combinations such as "reset_config srst_only srst_pulls_trst"
561 * only req_tlr_or_trst and srst can have a transition for a
562 * call as the effects of transitioning both at the "same time"
563 * are undefined, but when srst_pulls_trst or vice versa,
564 * then trst & srst *must* be asserted together.
566 void jtag_add_reset(int req_tlr_or_trst, int srst);
570 * Function jtag_set_end_state
572 * Set a global variable to \a state if \a state != TAP_INVALID.
574 * Return the value of the global variable.
577 tap_state_t jtag_set_end_state(tap_state_t state);
579 * Function jtag_get_end_state
581 * Return the value of the global variable for end state
584 tap_state_t jtag_get_end_state(void);
585 void jtag_add_sleep(uint32_t us);
589 * Function jtag_add_stable_clocks
590 * first checks that the state in which the clocks are to be issued is
591 * stable, then queues up clock_count clocks for transmission.
593 void jtag_add_clocks(int num_cycles);
597 * For software FIFO implementations, the queued commands can be executed
598 * during this call or earlier. A sw queue might decide to push out
599 * some of the jtag_add_xxx() operations once the queue is "big enough".
601 * This fn will return an error code if any of the prior jtag_add_xxx()
602 * calls caused a failure, e.g. check failure. Note that it does not
603 * matter if the operation was executed *before* jtag_execute_queue(),
604 * jtag_execute_queue() will still return an error code.
606 * All jtag_add_xxx() calls that have in_handler != NULL will have been
607 * executed when this fn returns, but if what has been queued only
608 * clocks data out, without reading anything back, then JTAG could
609 * be running *after* jtag_execute_queue() returns. The API does
610 * not define a way to flush a hw FIFO that runs *after*
611 * jtag_execute_queue() returns.
613 * jtag_add_xxx() commands can either be executed immediately or
614 * at some time between the jtag_add_xxx() fn call and jtag_execute_queue().
616 int jtag_execute_queue(void);
618 /// same as jtag_execute_queue() but does not clear the error flag
619 void jtag_execute_queue_noclear(void);
621 /// @returns the number of times the scan queue has been flushed
622 int jtag_get_flush_queue_count(void);
624 /// Report Tcl event to all TAPs
625 void jtag_notify_event(enum jtag_event);
628 /* can be implemented by hw + sw */
629 int jtag_power_dropout(int* dropout);
630 int jtag_srst_asserted(int* srst_asserted);
632 /* JTAG support functions */
635 * Execute jtag queue and check value with an optional mask.
636 * @param field Pointer to scan field.
637 * @param value Pointer to scan value.
638 * @param mask Pointer to scan mask; may be NULL.
639 * @returns Nothing, but calls jtag_set_error() on any error.
641 void jtag_check_value_mask(struct scan_field *field, uint8_t *value, uint8_t *mask);
643 void jtag_sleep(uint32_t us);
646 * The JTAG subsystem defines a number of error codes,
647 * using codes between -100 and -199.
649 #define ERROR_JTAG_INIT_FAILED (-100)
650 #define ERROR_JTAG_INVALID_INTERFACE (-101)
651 #define ERROR_JTAG_NOT_IMPLEMENTED (-102)
652 #define ERROR_JTAG_TRST_ASSERTED (-103)
653 #define ERROR_JTAG_QUEUE_FAILED (-104)
654 #define ERROR_JTAG_NOT_STABLE_STATE (-105)
655 #define ERROR_JTAG_DEVICE_ERROR (-107)
656 #define ERROR_JTAG_STATE_INVALID (-108)
657 #define ERROR_JTAG_TRANSITION_INVALID (-109)
658 #define ERROR_JTAG_INIT_SOFT_FAIL (-110)
661 * jtag_add_dr_out() is a version of jtag_add_dr_scan() which
662 * only scans data out. It operates on 32 bit integers instead
663 * of 8 bit, which makes it a better impedance match with
664 * the calling code which often operate on 32 bit integers.
666 * Current or end_state can not be TAP_RESET. end_state can be TAP_INVALID
668 * num_bits[i] is the number of bits to clock out from value[i] LSB first.
670 * If the device is in bypass, then that is an error condition in
671 * the caller code that is not detected by this fn, whereas
672 * jtag_add_dr_scan() does detect it. Similarly if the device is not in
673 * bypass, data must be passed to it.
675 * If anything fails, then jtag_error will be set and jtag_execute() will
676 * return an error. There is no way to determine if there was a failure
677 * during this function call.
679 * This is an inline fn to speed up embedded hosts. Also note that
680 * interface_jtag_add_dr_out() can be a *small* inline function for
683 * There is no jtag_add_dr_outin() version of this fn that also allows
684 * clocking data back in. Patches gladly accepted!
686 void jtag_add_dr_out(struct jtag_tap* tap,
687 int num_fields, const int* num_bits, const uint32_t* value,
688 tap_state_t end_state);
692 * Set the current JTAG core execution error, unless one was set
693 * by a previous call previously. Driver or application code must
694 * use jtag_error_clear to reset jtag_error once this routine has been
695 * called with a non-zero error code.
697 void jtag_set_error(int error);
698 /// @returns The current value of jtag_error
699 int jtag_get_error(void);
701 * Resets jtag_error to ERROR_OK, returning its previous value.
702 * @returns The previous value of @c jtag_error.
704 int jtag_error_clear(void);
707 * Return true if it's safe for a background polling task to access the
708 * JTAG scan chain. Polling may be explicitly disallowed, and is also
709 * unsafe while nTRST is active or the JTAG clock is gated off.,
711 bool is_jtag_poll_safe(void);
714 * Return flag reporting whether JTAG polling is disallowed.
716 bool jtag_poll_get_enabled(void);
719 * Assign flag reporting whether JTAG polling is disallowed.
721 void jtag_poll_set_enabled(bool value);