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"
30 #ifdef _DEBUG_JTAG_IO_
31 #define DEBUG_JTAG_IO(expr ...) LOG_DEBUG(expr)
33 #define DEBUG_JTAG_IO(expr ...)
36 #ifndef DEBUG_JTAG_IOZ
37 #define DEBUG_JTAG_IOZ 64
40 /*-----<Macros>--------------------------------------------------*/
43 * When given an array, compute its DIMension; in other words, the
44 * number of elements in the array
46 #define DIM(x) (sizeof(x)/sizeof((x)[0]))
48 /** Calculate the number of bytes required to hold @a n TAP scan bits */
49 #define TAP_SCAN_BYTES(n) CEIL(n, 8)
51 /*-----</Macros>-------------------------------------------------*/
54 * Defines JTAG Test Access Port states.
56 * These definitions were gleaned from the ARM7TDMI-S Technical
57 * Reference Manual and validated against several other ARM core
58 * technical manuals. tap_get_tms_path() is sensitive to this numbering
59 * and ordering of the TAP states; furthermore, some interfaces require
60 * specific numbers be used, as they are handed-off directly to their
61 * hardware implementations.
63 typedef enum tap_state
66 /* These are the old numbers. Leave as-is for now... */
67 TAP_RESET
= 0, TAP_IDLE
= 8,
68 TAP_DRSELECT
= 1, TAP_DRCAPTURE
= 2, TAP_DRSHIFT
= 3, TAP_DREXIT1
= 4,
69 TAP_DRPAUSE
= 5, TAP_DREXIT2
= 6, TAP_DRUPDATE
= 7,
70 TAP_IRSELECT
= 9, TAP_IRCAPTURE
= 10, TAP_IRSHIFT
= 11, TAP_IREXIT1
= 12,
71 TAP_IRPAUSE
= 13, TAP_IREXIT2
= 14, TAP_IRUPDATE
= 15,
73 TAP_NUM_STATES
= 16, TAP_INVALID
= -1,
75 /* Proper ARM recommended numbers */
93 TAP_NUM_STATES
= 0x10,
100 * Function tap_state_name
101 * Returns a string suitable for display representing the JTAG tap_state
103 const char* tap_state_name(tap_state_t state
);
105 /// The current TAP state of the pending JTAG command queue.
106 extern tap_state_t cmd_queue_cur_state
;
109 * This structure defines a single scan field in the scan. It provides
110 * fields for the field's width and pointers to scan input and output
113 * In addition, this structure includes a value and mask that is used by
114 * jtag_add_dr_scan_check() to validate the value that was scanned out.
116 * The allocated, modified, and intmp fields are internal work space.
118 typedef struct scan_field_s
120 /// A pointer to the tap structure to which this field refers.
123 /// The number of bits this field specifies (up to 32)
125 /// A pointer to value to be scanned into the device
127 /// A pointer to a 32-bit memory location for data scanned out
130 /// The value used to check the data scanned out.
132 /// The mask to go with check_value
135 /// in_value has been allocated for the queue
137 /// Indicates we modified the in_value.
139 /// temporary storage for performing value checks synchronously
143 typedef struct jtag_tap_event_action_s jtag_tap_event_action_t
;
145 /* this is really: typedef jtag_tap_t */
146 /* But - the typedef is done in "types.h" */
147 /* due to "forward decloration reasons" */
152 const char* dotted_name
;
153 int abs_chain_position
;
154 /// Is this TAP enabled?
156 int ir_length
; /**< size of instruction register */
157 u32 ir_capture_value
;
158 u8
* expected
; /**< Capture-IR expected value */
160 u8
* expected_mask
; /**< Capture-IR expected mask */
162 /**< device identification code */
164 /// Array of expected identification codes */
166 /// Number of expected identification codes
169 /// current instruction
171 /// Bypass register selected
174 jtag_tap_event_action_t
*event_action
;
176 jtag_tap_t
* next_tap
;
178 extern jtag_tap_t
* jtag_all_taps(void);
179 extern const char *jtag_tap_name(const jtag_tap_t
*tap
);
180 extern jtag_tap_t
* jtag_tap_by_string(const char* dotted_name
);
181 extern jtag_tap_t
* jtag_tap_by_jim_obj(Jim_Interp
* interp
, Jim_Obj
* obj
);
182 extern jtag_tap_t
* jtag_tap_by_position(unsigned abs_position
);
183 extern unsigned jtag_tap_count_enabled(void);
184 extern unsigned jtag_tap_count(void);
186 static __inline__ jtag_tap_t
* jtag_tap_next_enabled(jtag_tap_t
* p
)
190 /* start at the head of list */
195 /* start *after* this one */
214 enum reset_line_mode
{
215 LINE_OPEN_DRAIN
= 0x0,
216 LINE_PUSH_PULL
= 0x1,
220 * There are three cases when JTAG_TRST_ASSERTED callback is invoked. The
221 * event is invoked *after* TRST is asserted(or queued rather). It is illegal
222 * to communicate with the JTAG interface during the callback(as there is
223 * currently a queue being built).
234 extern char* jtag_event_strings
[];
236 enum jtag_tap_event
{
237 JTAG_TAP_EVENT_ENABLE
,
238 JTAG_TAP_EVENT_DISABLE
241 extern const Jim_Nvp nvp_jtag_tap_event
[];
243 struct jtag_tap_event_action_s
245 enum jtag_tap_event event
;
247 jtag_tap_event_action_t
* next
;
250 extern int jtag_trst
;
251 extern int jtag_srst
;
253 typedef struct jtag_event_callback_s
255 int (*callback
)(enum jtag_event event
, void* priv
);
257 struct jtag_event_callback_s
* next
;
258 } jtag_event_callback_t
;
260 extern jtag_event_callback_t
* jtag_event_callbacks
;
262 extern int jtag_speed
;
263 extern int jtag_speed_post_reset
;
267 RESET_HAS_TRST
= 0x1,
268 RESET_HAS_SRST
= 0x2,
269 RESET_TRST_AND_SRST
= 0x3,
270 RESET_SRST_PULLS_TRST
= 0x4,
271 RESET_TRST_PULLS_SRST
= 0x8,
272 RESET_TRST_OPEN_DRAIN
= 0x10,
273 RESET_SRST_PUSH_PULL
= 0x20,
276 extern enum reset_types jtag_reset_config
;
279 * Initialize interface upon startup. Return a successful no-op upon
280 * subsequent invocations.
282 extern int jtag_interface_init(struct command_context_s
* cmd_ctx
);
284 /// Shutdown the JTAG interface upon program exit.
285 extern int jtag_interface_quit(void);
288 * Initialize JTAG chain using only a RESET reset. If init fails,
291 extern int jtag_init(struct command_context_s
* cmd_ctx
);
293 /// reset, then initialize JTAG chain
294 extern int jtag_init_reset(struct command_context_s
* cmd_ctx
);
295 extern int jtag_register_commands(struct command_context_s
* cmd_ctx
);
299 * The JTAG interface can be implemented with a software or hardware fifo.
301 * TAP_DRSHIFT and TAP_IRSHIFT are illegal end states; however,
302 * TAP_DRSHIFT/IRSHIFT can be emulated as end states, by using longer
305 * Code that is relatively insensitive to the path taken through state
306 * machine (as long as it is JTAG compliant) can use @a endstate for
307 * jtag_add_xxx_scan(). Otherwise, the pause state must be specified as
308 * end state and a subsequent jtag_add_pathmove() must be issued.
312 * Generate an IR SCAN with a list of scan fields with one entry for
315 * If the input field list contains an instruction value for a TAP then
316 * that is used otherwise the TAP is set to bypass.
318 * TAPs for which no fields are passed are marked as bypassed for
319 * subsequent DR SCANs.
322 extern void jtag_add_ir_scan(int num_fields
, scan_field_t
* fields
, tap_state_t endstate
);
324 * The same as jtag_add_ir_scan except no verification is performed out
327 extern void jtag_add_ir_scan_noverify(int num_fields
, const scan_field_t
*fields
, tap_state_t state
);
329 * Duplicate the scan fields passed into the function into an IR SCAN
330 * command. This function assumes that the caller handles extra fields
333 extern void jtag_add_plain_ir_scan(int num_fields
, const scan_field_t
* fields
, tap_state_t endstate
);
337 * Set in_value to point to 32 bits of memory to scan into. This
338 * function is a way to handle the case of synchronous and asynchronous
341 * In the event of an asynchronous queue execution the queue buffer
342 * allocation method is used, for the synchronous case the temporary 32
343 * bits come from the input field itself.
345 extern void jtag_alloc_in_value32(scan_field_t
*field
);
348 * Generate a DR SCAN using the fields passed to the function.
349 * For connected TAPs, the function checks in_fields and uses fields
350 * specified there. For bypassed TAPs, the function generates a dummy
351 * 1-bit field. The bypass status of TAPs is set by jtag_add_ir_scan().
353 extern void jtag_add_dr_scan(int num_fields
, const scan_field_t
* fields
, tap_state_t endstate
);
354 /// A version of jtag_add_dr_scan() that uses the check_value/mask fields
355 extern void jtag_add_dr_scan_check(int num_fields
, scan_field_t
* fields
, tap_state_t endstate
);
357 * Duplicate the scan fields passed into the function into a DR SCAN
358 * command. Unlike jtag_add_dr_scan(), this function assumes that the
359 * caller handles extra fields for bypassed TAPs.
361 extern void jtag_add_plain_dr_scan(int num_fields
, const scan_field_t
* fields
, tap_state_t endstate
);
365 * Defines a simple JTAG callback that can allow conversions on data
366 * scanned in from an interface.
368 * This callback should only be used for conversion that cannot fail.
369 * For conversion types or checks that can fail, use the more complete
370 * variant: jtag_callback_t.
372 typedef void (*jtag_callback1_t
)(u8
*in
);
374 /// A simpler version of jtag_add_callback4().
375 extern void jtag_add_callback(jtag_callback1_t
, u8
*in
);
379 * Defines the type of data passed to the jtag_callback_t interface.
380 * The underlying type must allow storing an @c int or pointer type.
382 typedef intptr_t jtag_callback_data_t
;
385 * Defines the interface of the JTAG callback mechanism.
387 * @param in the pointer to the data clocked in
388 * @param data1 An integer big enough to use as an @c int or a pointer.
389 * @param data2 An integer big enough to use as an @c int or a pointer.
390 * @param data3 An integer big enough to use as an @c int or a pointer.
391 * @returns an error code
393 typedef int (*jtag_callback_t
)(u8
*in
, jtag_callback_data_t data1
, jtag_callback_data_t data2
, jtag_callback_data_t data3
);
397 * This callback can be executed immediately the queue has been flushed.
399 * The JTAG queue can be executed synchronously or asynchronously.
400 * Typically for USB, the queue is executed asynchronously. For
401 * low-latency interfaces, the queue may be executed synchronously.
403 * The callback mechanism is very general and does not make many
404 * assumptions about what the callback does or what its arguments are.
405 * These callbacks are typically executed *after* the *entire* JTAG
406 * queue has been executed for e.g. USB interfaces, and they are
407 * guaranteeed to be invoked in the order that they were queued.
409 * If the execution of the queue fails before the callbacks, then --
410 * depending on driver implementation -- the callbacks may or may not be
411 * invoked. @todo Can we make this behavior consistent?
413 * The strange name is due to C's lack of overloading using function
416 * @param f The callback function to add.
417 * @param in Typically used to point to the data to operate on.
418 * Frequently this will be the data clocked in during a shift operation.
419 * @param data1 An integer big enough to use as an @c int or a pointer.
420 * @param data2 An integer big enough to use as an @c int or a pointer.
421 * @param data3 An integer big enough to use as an @c int or a pointer.
424 extern void jtag_add_callback4(jtag_callback_t f
, u8
*in
,
425 jtag_callback_data_t data1
, jtag_callback_data_t data2
,
426 jtag_callback_data_t data3
);
430 * Run a TAP_RESET reset where the end state is TAP_RESET,
431 * regardless of the start state.
433 extern void jtag_add_tlr(void);
436 * Application code *must* assume that interfaces will
437 * implement transitions between states with different
438 * paths and path lengths through the state diagram. The
439 * path will vary across interface and also across versions
440 * of the same interface over time. Even if the OpenOCD code
441 * is unchanged, the actual path taken may vary over time
442 * and versions of interface firmware or PCB revisions.
444 * Use jtag_add_pathmove() when specific transition sequences
447 * Do not use jtag_add_pathmove() unless you need to, but do use it
450 * DANGER! If the target is dependent upon a particular sequence
451 * of transitions for things to work correctly(e.g. as a workaround
452 * for an errata that contradicts the JTAG standard), then pathmove
453 * must be used, even if some jtag interfaces happen to use the
454 * desired path. Worse, the jtag interface used for testing a
455 * particular implementation, could happen to use the "desired"
456 * path when transitioning to/from end
459 * A list of unambigious single clock state transitions, not
460 * all drivers can support this, but it is required for e.g.
461 * XScale and Xilinx support
463 * Note! TAP_RESET must not be used in the path!
465 * Note that the first on the list must be reachable
466 * via a single transition from the current state.
468 * All drivers are required to implement jtag_add_pathmove().
469 * However, if the pathmove sequence can not be precisely
470 * executed, an interface_jtag_add_pathmove() or jtag_execute_queue()
471 * must return an error. It is legal, but not recommended, that
472 * a driver returns an error in all cases for a pathmove if it
473 * can only implement a few transitions and therefore
474 * a partial implementation of pathmove would have little practical
477 * If an error occurs, jtag_error will contain one of these error codes:
478 * - ERROR_JTAG_NOT_STABLE_STATE -- The final state was not stable.
479 * - ERROR_JTAG_STATE_INVALID -- The path passed through TAP_RESET.
480 * - ERROR_JTAG_TRANSITION_INVALID -- The path includes invalid
483 extern void jtag_add_pathmove(int num_states
, const tap_state_t
* path
);
486 * Goes to TAP_IDLE (if we're not already there), cycle
487 * precisely num_cycles in the TAP_IDLE state, after which move
488 * to @a endstate (unless it is also TAP_IDLE).
490 * @param num_cycles Number of cycles in TAP_IDLE state. This argument
491 * may be 0, in which case this routine will navigate to @a endstate
493 * @param endstate The final state.
495 extern void jtag_add_runtest(int num_cycles
, tap_state_t endstate
);
498 * A reset of the TAP state machine can be requested.
500 * Whether tms or trst reset is used depends on the capabilities of
501 * the target and jtag interface(reset_config command configures this).
503 * srst can driver a reset of the TAP state machine and vice
506 * Application code may need to examine value of jtag_reset_config
507 * to determine the proper codepath
509 * DANGER! Even though srst drives trst, trst might not be connected to
510 * the interface, and it might actually be *harmful* to assert trst in this case.
512 * This is why combinations such as "reset_config srst_only srst_pulls_trst"
515 * only req_tlr_or_trst and srst can have a transition for a
516 * call as the effects of transitioning both at the "same time"
517 * are undefined, but when srst_pulls_trst or vice versa,
518 * then trst & srst *must* be asserted together.
520 extern void jtag_add_reset(int req_tlr_or_trst
, int srst
);
524 * Function jtag_set_end_state
526 * Set a global variable to \a state if \a state != TAP_INVALID.
528 * Return the value of the global variable.
531 extern tap_state_t
jtag_set_end_state(tap_state_t state
);
533 * Function jtag_get_end_state
535 * Return the value of the global variable for end state
538 extern tap_state_t
jtag_get_end_state(void);
539 extern void jtag_add_sleep(u32 us
);
543 * Function jtag_add_stable_clocks
544 * first checks that the state in which the clocks are to be issued is
545 * stable, then queues up clock_count clocks for transmission.
547 void jtag_add_clocks(int num_cycles
);
551 * For software FIFO implementations, the queued commands can be executed
552 * during this call or earlier. A sw queue might decide to push out
553 * some of the jtag_add_xxx() operations once the queue is "big enough".
555 * This fn will return an error code if any of the prior jtag_add_xxx()
556 * calls caused a failure, e.g. check failure. Note that it does not
557 * matter if the operation was executed *before* jtag_execute_queue(),
558 * jtag_execute_queue() will still return an error code.
560 * All jtag_add_xxx() calls that have in_handler!=NULL will have been
561 * executed when this fn returns, but if what has been queued only
562 * clocks data out, without reading anything back, then JTAG could
563 * be running *after* jtag_execute_queue() returns. The API does
564 * not define a way to flush a hw FIFO that runs *after*
565 * jtag_execute_queue() returns.
567 * jtag_add_xxx() commands can either be executed immediately or
568 * at some time between the jtag_add_xxx() fn call and jtag_execute_queue().
570 extern int jtag_execute_queue(void);
572 /* same as jtag_execute_queue() but does not clear the error flag */
573 extern void jtag_execute_queue_noclear(void);
576 * The jtag_error variable is set when an error occurs while executing
579 * This flag can also be set from application code, if an error happens
580 * during processing that should be reported during jtag_execute_queue().
582 * It is cleared by jtag_execute_queue().
584 extern int jtag_error
;
586 static __inline__
void jtag_set_error(int error
)
588 if ((error
==ERROR_OK
)||(jtag_error
!=ERROR_OK
))
590 /* keep first error */
597 * Resets jtag_error to ERROR_OK, returning its previous value.
598 * @returns The previous value of @c jtag_error.
600 static inline int jtag_error_clear(void)
602 int temp
= jtag_error
;
603 jtag_error
= ERROR_OK
;
607 /* can be implemented by hw+sw */
608 extern int jtag_power_dropout(int* dropout
);
609 extern int jtag_srst_asserted(int* srst_asserted
);
611 /* JTAG support functions */
614 * Execute jtag queue and check value with an optional mask.
615 * @param field Pointer to scan field.
616 * @param value Pointer to scan value.
617 * @param mask Pointer to scan mask; may be NULL.
618 * @returns Nothing, but calls jtag_set_error() on any error.
620 extern void jtag_check_value_mask(scan_field_t
*field
, u8
*value
, u8
*mask
);
622 extern void jtag_sleep(u32 us
);
623 extern int jtag_call_event_callbacks(enum jtag_event event
);
624 extern int jtag_register_event_callback(int (* callback
)(enum jtag_event event
, void* priv
), void* priv
);
626 extern int jtag_verify_capture_ir
;
628 void jtag_tap_handle_event(jtag_tap_t
* tap
, enum jtag_tap_event e
);
631 * The JTAG subsystem defines a number of error codes,
632 * using codes between -100 and -199.
634 #define ERROR_JTAG_INIT_FAILED (-100)
635 #define ERROR_JTAG_INVALID_INTERFACE (-101)
636 #define ERROR_JTAG_NOT_IMPLEMENTED (-102)
637 #define ERROR_JTAG_TRST_ASSERTED (-103)
638 #define ERROR_JTAG_QUEUE_FAILED (-104)
639 #define ERROR_JTAG_NOT_STABLE_STATE (-105)
640 #define ERROR_JTAG_DEVICE_ERROR (-107)
641 #define ERROR_JTAG_STATE_INVALID (-108)
642 #define ERROR_JTAG_TRANSITION_INVALID (-109)
645 * jtag_add_dr_out() is a version of jtag_add_dr_scan() which
646 * only scans data out. It operates on 32 bit integers instead
647 * of 8 bit, which makes it a better impedance match with
648 * the calling code which often operate on 32 bit integers.
650 * Current or end_state can not be TAP_RESET. end_state can be TAP_INVALID
652 * num_bits[i] is the number of bits to clock out from value[i] LSB first.
654 * If the device is in bypass, then that is an error condition in
655 * the caller code that is not detected by this fn, whereas
656 * jtag_add_dr_scan() does detect it. Similarly if the device is not in
657 * bypass, data must be passed to it.
659 * If anything fails, then jtag_error will be set and jtag_execute() will
660 * return an error. There is no way to determine if there was a failure
661 * during this function call.
663 * This is an inline fn to speed up embedded hosts. Also note that
664 * interface_jtag_add_dr_out() can be a *small* inline function for
667 * There is no jtag_add_dr_outin() version of this fn that also allows
668 * clocking data back in. Patches gladly accepted!
670 extern void jtag_add_dr_out(jtag_tap_t
* tap
,
671 int num_fields
, const int* num_bits
, const u32
* value
,
672 tap_state_t end_state
);
676 * jtag_add_statemove() moves from the current state to @a goal_state.
678 * @param goal_state The final TAP state.
679 * @return ERROR_OK on success, or an error code on failure.
681 * Moves from the current state to the goal \a state.
683 * This needs to be handled according to the xsvf spec, see the XSTATE
684 * command description. From the XSVF spec, pertaining to XSTATE:
686 * For special states known as stable states (Test-Logic-Reset,
687 * Run-Test/Idle, Pause-DR, Pause- IR), an XSVF interpreter follows
688 * predefined TAP state paths when the starting state is a stable state
689 * and when the XSTATE specifies a new stable state. See the STATE
690 * command in the [Ref 5] for the TAP state paths between stable
693 * For non-stable states, XSTATE should specify a state that is only one
694 * TAP state transition distance from the current TAP state to avoid
695 * undefined TAP state paths. A sequence of multiple XSTATE commands can
696 * be issued to transition the TAP through a specific state path.
698 * @note Unless @c tms_bits holds a path that agrees with [Ref 5] in the
699 * above spec, then this code is not fully conformant to the xsvf spec.
700 * This puts a burden on tap_get_tms_path() function from the xsvf spec.
701 * If in doubt, you should confirm that that burden is being met.
703 * Otherwise, @a goal_state must be immediately reachable in one clock
704 * cycle, and does not need to be a stable state.
706 extern int jtag_add_statemove(tap_state_t goal_state
);
708 /// @returns the number of times the scan queue has been flushed
709 int jtag_get_flush_queue_count(void);
711 void jtag_set_nsrst_delay(unsigned delay
);
712 unsigned jtag_get_nsrst_delay(void);
714 void jtag_set_ntrst_delay(unsigned delay
);
715 unsigned jtag_get_ntrst_delay(void);
717 void jtag_set_speed_khz(unsigned speed
);
718 unsigned jtag_get_speed_khz(void);
720 void jtag_set_verify(bool enable
);
721 bool jtag_will_verify(void);