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 enum jtag_tap_event
{
235 JTAG_TAP_EVENT_ENABLE
,
236 JTAG_TAP_EVENT_DISABLE
239 struct jtag_tap_event_action_s
241 enum jtag_tap_event event
;
243 jtag_tap_event_action_t
* next
;
246 /// @returns The current state of TRST.
247 int jtag_get_trst(void);
248 /// @returns The current state of SRST.
249 int jtag_get_srst(void);
251 typedef struct jtag_event_callback_s
253 int (*callback
)(enum jtag_event event
, void* priv
);
255 struct jtag_event_callback_s
* next
;
256 } jtag_event_callback_t
;
258 /// @returns The current JTAG speed setting.
259 int jtag_get_speed(void);
261 * Set the JTAG speed. This routine will call the underlying
262 * interface @c speed callback, if the interface has been initialized.
263 * @param speed The new speed setting.
264 * @returns ERROR_OK during configuration or on success, or an error
265 * code returned from the interface @c speed callback.
267 int jtag_set_speed(int speed
);
271 RESET_HAS_TRST
= 0x1,
272 RESET_HAS_SRST
= 0x2,
273 RESET_TRST_AND_SRST
= 0x3,
274 RESET_SRST_PULLS_TRST
= 0x4,
275 RESET_TRST_PULLS_SRST
= 0x8,
276 RESET_TRST_OPEN_DRAIN
= 0x10,
277 RESET_SRST_PUSH_PULL
= 0x20,
280 enum reset_types
jtag_get_reset_config(void);
281 void jtag_set_reset_config(enum reset_types type
);
284 * Initialize interface upon startup. Return a successful no-op upon
285 * subsequent invocations.
287 extern int jtag_interface_init(struct command_context_s
* cmd_ctx
);
289 /// Shutdown the JTAG interface upon program exit.
290 extern int jtag_interface_quit(void);
293 * Initialize JTAG chain using only a RESET reset. If init fails,
296 extern int jtag_init(struct command_context_s
* cmd_ctx
);
298 /// reset, then initialize JTAG chain
299 extern int jtag_init_reset(struct command_context_s
* cmd_ctx
);
300 extern int jtag_register_commands(struct command_context_s
* cmd_ctx
);
304 * The JTAG interface can be implemented with a software or hardware fifo.
306 * TAP_DRSHIFT and TAP_IRSHIFT are illegal end states; however,
307 * TAP_DRSHIFT/IRSHIFT can be emulated as end states, by using longer
310 * Code that is relatively insensitive to the path taken through state
311 * machine (as long as it is JTAG compliant) can use @a endstate for
312 * jtag_add_xxx_scan(). Otherwise, the pause state must be specified as
313 * end state and a subsequent jtag_add_pathmove() must be issued.
317 * Generate an IR SCAN with a list of scan fields with one entry for
320 * If the input field list contains an instruction value for a TAP then
321 * that is used otherwise the TAP is set to bypass.
323 * TAPs for which no fields are passed are marked as bypassed for
324 * subsequent DR SCANs.
327 extern void jtag_add_ir_scan(int num_fields
, scan_field_t
* fields
, tap_state_t endstate
);
329 * The same as jtag_add_ir_scan except no verification is performed out
332 extern void jtag_add_ir_scan_noverify(int num_fields
, const scan_field_t
*fields
, tap_state_t state
);
334 * Duplicate the scan fields passed into the function into an IR SCAN
335 * command. This function assumes that the caller handles extra fields
338 extern void jtag_add_plain_ir_scan(int num_fields
, const scan_field_t
* fields
, tap_state_t endstate
);
342 * Set in_value to point to 32 bits of memory to scan into. This
343 * function is a way to handle the case of synchronous and asynchronous
346 * In the event of an asynchronous queue execution the queue buffer
347 * allocation method is used, for the synchronous case the temporary 32
348 * bits come from the input field itself.
350 extern void jtag_alloc_in_value32(scan_field_t
*field
);
353 * Generate a DR SCAN using the fields passed to the function.
354 * For connected TAPs, the function checks in_fields and uses fields
355 * specified there. For bypassed TAPs, the function generates a dummy
356 * 1-bit field. The bypass status of TAPs is set by jtag_add_ir_scan().
358 extern void jtag_add_dr_scan(int num_fields
, const scan_field_t
* fields
, tap_state_t endstate
);
359 /// A version of jtag_add_dr_scan() that uses the check_value/mask fields
360 extern void jtag_add_dr_scan_check(int num_fields
, scan_field_t
* fields
, tap_state_t endstate
);
362 * Duplicate the scan fields passed into the function into a DR SCAN
363 * command. Unlike jtag_add_dr_scan(), this function assumes that the
364 * caller handles extra fields for bypassed TAPs.
366 extern void jtag_add_plain_dr_scan(int num_fields
, const scan_field_t
* fields
, tap_state_t endstate
);
370 * Defines a simple JTAG callback that can allow conversions on data
371 * scanned in from an interface.
373 * This callback should only be used for conversion that cannot fail.
374 * For conversion types or checks that can fail, use the more complete
375 * variant: jtag_callback_t.
377 typedef void (*jtag_callback1_t
)(u8
*in
);
379 /// A simpler version of jtag_add_callback4().
380 extern void jtag_add_callback(jtag_callback1_t
, u8
*in
);
384 * Defines the type of data passed to the jtag_callback_t interface.
385 * The underlying type must allow storing an @c int or pointer type.
387 typedef intptr_t jtag_callback_data_t
;
390 * Defines the interface of the JTAG callback mechanism.
392 * @param in the pointer to the data clocked in
393 * @param data1 An integer big enough to use as an @c int or a pointer.
394 * @param data2 An integer big enough to use as an @c int or a pointer.
395 * @param data3 An integer big enough to use as an @c int or a pointer.
396 * @returns an error code
398 typedef int (*jtag_callback_t
)(u8
*in
, jtag_callback_data_t data1
, jtag_callback_data_t data2
, jtag_callback_data_t data3
);
402 * This callback can be executed immediately the queue has been flushed.
404 * The JTAG queue can be executed synchronously or asynchronously.
405 * Typically for USB, the queue is executed asynchronously. For
406 * low-latency interfaces, the queue may be executed synchronously.
408 * The callback mechanism is very general and does not make many
409 * assumptions about what the callback does or what its arguments are.
410 * These callbacks are typically executed *after* the *entire* JTAG
411 * queue has been executed for e.g. USB interfaces, and they are
412 * guaranteeed to be invoked in the order that they were queued.
414 * If the execution of the queue fails before the callbacks, then --
415 * depending on driver implementation -- the callbacks may or may not be
416 * invoked. @todo Can we make this behavior consistent?
418 * The strange name is due to C's lack of overloading using function
421 * @param f The callback function to add.
422 * @param in Typically used to point to the data to operate on.
423 * Frequently this will be the data clocked in during a shift operation.
424 * @param data1 An integer big enough to use as an @c int or a pointer.
425 * @param data2 An integer big enough to use as an @c int or a pointer.
426 * @param data3 An integer big enough to use as an @c int or a pointer.
429 extern void jtag_add_callback4(jtag_callback_t f
, u8
*in
,
430 jtag_callback_data_t data1
, jtag_callback_data_t data2
,
431 jtag_callback_data_t data3
);
435 * Run a TAP_RESET reset where the end state is TAP_RESET,
436 * regardless of the start state.
438 extern void jtag_add_tlr(void);
441 * Application code *must* assume that interfaces will
442 * implement transitions between states with different
443 * paths and path lengths through the state diagram. The
444 * path will vary across interface and also across versions
445 * of the same interface over time. Even if the OpenOCD code
446 * is unchanged, the actual path taken may vary over time
447 * and versions of interface firmware or PCB revisions.
449 * Use jtag_add_pathmove() when specific transition sequences
452 * Do not use jtag_add_pathmove() unless you need to, but do use it
455 * DANGER! If the target is dependent upon a particular sequence
456 * of transitions for things to work correctly(e.g. as a workaround
457 * for an errata that contradicts the JTAG standard), then pathmove
458 * must be used, even if some jtag interfaces happen to use the
459 * desired path. Worse, the jtag interface used for testing a
460 * particular implementation, could happen to use the "desired"
461 * path when transitioning to/from end
464 * A list of unambigious single clock state transitions, not
465 * all drivers can support this, but it is required for e.g.
466 * XScale and Xilinx support
468 * Note! TAP_RESET must not be used in the path!
470 * Note that the first on the list must be reachable
471 * via a single transition from the current state.
473 * All drivers are required to implement jtag_add_pathmove().
474 * However, if the pathmove sequence can not be precisely
475 * executed, an interface_jtag_add_pathmove() or jtag_execute_queue()
476 * must return an error. It is legal, but not recommended, that
477 * a driver returns an error in all cases for a pathmove if it
478 * can only implement a few transitions and therefore
479 * a partial implementation of pathmove would have little practical
482 * If an error occurs, jtag_error will contain one of these error codes:
483 * - ERROR_JTAG_NOT_STABLE_STATE -- The final state was not stable.
484 * - ERROR_JTAG_STATE_INVALID -- The path passed through TAP_RESET.
485 * - ERROR_JTAG_TRANSITION_INVALID -- The path includes invalid
488 extern void jtag_add_pathmove(int num_states
, const tap_state_t
* path
);
491 * Goes to TAP_IDLE (if we're not already there), cycle
492 * precisely num_cycles in the TAP_IDLE state, after which move
493 * to @a endstate (unless it is also TAP_IDLE).
495 * @param num_cycles Number of cycles in TAP_IDLE state. This argument
496 * may be 0, in which case this routine will navigate to @a endstate
498 * @param endstate The final state.
500 extern void jtag_add_runtest(int num_cycles
, tap_state_t endstate
);
503 * A reset of the TAP state machine can be requested.
505 * Whether tms or trst reset is used depends on the capabilities of
506 * the target and jtag interface(reset_config command configures this).
508 * srst can driver a reset of the TAP state machine and vice
511 * Application code may need to examine value of jtag_reset_config
512 * to determine the proper codepath
514 * DANGER! Even though srst drives trst, trst might not be connected to
515 * the interface, and it might actually be *harmful* to assert trst in this case.
517 * This is why combinations such as "reset_config srst_only srst_pulls_trst"
520 * only req_tlr_or_trst and srst can have a transition for a
521 * call as the effects of transitioning both at the "same time"
522 * are undefined, but when srst_pulls_trst or vice versa,
523 * then trst & srst *must* be asserted together.
525 extern void jtag_add_reset(int req_tlr_or_trst
, int srst
);
529 * Function jtag_set_end_state
531 * Set a global variable to \a state if \a state != TAP_INVALID.
533 * Return the value of the global variable.
536 extern tap_state_t
jtag_set_end_state(tap_state_t state
);
538 * Function jtag_get_end_state
540 * Return the value of the global variable for end state
543 extern tap_state_t
jtag_get_end_state(void);
544 extern void jtag_add_sleep(u32 us
);
548 * Function jtag_add_stable_clocks
549 * first checks that the state in which the clocks are to be issued is
550 * stable, then queues up clock_count clocks for transmission.
552 void jtag_add_clocks(int num_cycles
);
556 * For software FIFO implementations, the queued commands can be executed
557 * during this call or earlier. A sw queue might decide to push out
558 * some of the jtag_add_xxx() operations once the queue is "big enough".
560 * This fn will return an error code if any of the prior jtag_add_xxx()
561 * calls caused a failure, e.g. check failure. Note that it does not
562 * matter if the operation was executed *before* jtag_execute_queue(),
563 * jtag_execute_queue() will still return an error code.
565 * All jtag_add_xxx() calls that have in_handler!=NULL will have been
566 * executed when this fn returns, but if what has been queued only
567 * clocks data out, without reading anything back, then JTAG could
568 * be running *after* jtag_execute_queue() returns. The API does
569 * not define a way to flush a hw FIFO that runs *after*
570 * jtag_execute_queue() returns.
572 * jtag_add_xxx() commands can either be executed immediately or
573 * at some time between the jtag_add_xxx() fn call and jtag_execute_queue().
575 extern int jtag_execute_queue(void);
577 /* same as jtag_execute_queue() but does not clear the error flag */
578 extern void jtag_execute_queue_noclear(void);
581 * Set the current JTAG core execution error, unless one was set
582 * by a previous call previously. Driver or application code must
583 * use jtag_error_clear to reset jtag_error once this routine has been
584 * called with a non-zero error code.
586 void jtag_set_error(int error
);
587 /// @returns The current value of jtag_error
588 int jtag_get_error(void);
590 * Resets jtag_error to ERROR_OK, returning its previous value.
591 * @returns The previous value of @c jtag_error.
593 int jtag_error_clear(void);
595 /* can be implemented by hw+sw */
596 extern int jtag_power_dropout(int* dropout
);
597 extern int jtag_srst_asserted(int* srst_asserted
);
599 /* JTAG support functions */
602 * Execute jtag queue and check value with an optional mask.
603 * @param field Pointer to scan field.
604 * @param value Pointer to scan value.
605 * @param mask Pointer to scan mask; may be NULL.
606 * @returns Nothing, but calls jtag_set_error() on any error.
608 extern void jtag_check_value_mask(scan_field_t
*field
, u8
*value
, u8
*mask
);
610 extern void jtag_sleep(u32 us
);
611 extern int jtag_call_event_callbacks(enum jtag_event event
);
612 extern int jtag_register_event_callback(int (* callback
)(enum jtag_event event
, void* priv
), void* priv
);
614 extern int jtag_verify_capture_ir
;
616 void jtag_tap_handle_event(jtag_tap_t
* tap
, enum jtag_tap_event e
);
619 * The JTAG subsystem defines a number of error codes,
620 * using codes between -100 and -199.
622 #define ERROR_JTAG_INIT_FAILED (-100)
623 #define ERROR_JTAG_INVALID_INTERFACE (-101)
624 #define ERROR_JTAG_NOT_IMPLEMENTED (-102)
625 #define ERROR_JTAG_TRST_ASSERTED (-103)
626 #define ERROR_JTAG_QUEUE_FAILED (-104)
627 #define ERROR_JTAG_NOT_STABLE_STATE (-105)
628 #define ERROR_JTAG_DEVICE_ERROR (-107)
629 #define ERROR_JTAG_STATE_INVALID (-108)
630 #define ERROR_JTAG_TRANSITION_INVALID (-109)
633 * jtag_add_dr_out() is a version of jtag_add_dr_scan() which
634 * only scans data out. It operates on 32 bit integers instead
635 * of 8 bit, which makes it a better impedance match with
636 * the calling code which often operate on 32 bit integers.
638 * Current or end_state can not be TAP_RESET. end_state can be TAP_INVALID
640 * num_bits[i] is the number of bits to clock out from value[i] LSB first.
642 * If the device is in bypass, then that is an error condition in
643 * the caller code that is not detected by this fn, whereas
644 * jtag_add_dr_scan() does detect it. Similarly if the device is not in
645 * bypass, data must be passed to it.
647 * If anything fails, then jtag_error will be set and jtag_execute() will
648 * return an error. There is no way to determine if there was a failure
649 * during this function call.
651 * This is an inline fn to speed up embedded hosts. Also note that
652 * interface_jtag_add_dr_out() can be a *small* inline function for
655 * There is no jtag_add_dr_outin() version of this fn that also allows
656 * clocking data back in. Patches gladly accepted!
658 extern void jtag_add_dr_out(jtag_tap_t
* tap
,
659 int num_fields
, const int* num_bits
, const u32
* value
,
660 tap_state_t end_state
);
664 * jtag_add_statemove() moves from the current state to @a goal_state.
666 * @param goal_state The final TAP state.
667 * @return ERROR_OK on success, or an error code on failure.
669 * Moves from the current state to the goal \a state.
671 * This needs to be handled according to the xsvf spec, see the XSTATE
672 * command description. From the XSVF spec, pertaining to XSTATE:
674 * For special states known as stable states (Test-Logic-Reset,
675 * Run-Test/Idle, Pause-DR, Pause- IR), an XSVF interpreter follows
676 * predefined TAP state paths when the starting state is a stable state
677 * and when the XSTATE specifies a new stable state. See the STATE
678 * command in the [Ref 5] for the TAP state paths between stable
681 * For non-stable states, XSTATE should specify a state that is only one
682 * TAP state transition distance from the current TAP state to avoid
683 * undefined TAP state paths. A sequence of multiple XSTATE commands can
684 * be issued to transition the TAP through a specific state path.
686 * @note Unless @c tms_bits holds a path that agrees with [Ref 5] in the
687 * above spec, then this code is not fully conformant to the xsvf spec.
688 * This puts a burden on tap_get_tms_path() function from the xsvf spec.
689 * If in doubt, you should confirm that that burden is being met.
691 * Otherwise, @a goal_state must be immediately reachable in one clock
692 * cycle, and does not need to be a stable state.
694 extern int jtag_add_statemove(tap_state_t goal_state
);
696 /// @returns the number of times the scan queue has been flushed
697 int jtag_get_flush_queue_count(void);
699 void jtag_set_nsrst_delay(unsigned delay
);
700 unsigned jtag_get_nsrst_delay(void);
702 void jtag_set_ntrst_delay(unsigned delay
);
703 unsigned jtag_get_ntrst_delay(void);
705 void jtag_set_speed_khz(unsigned speed
);
706 unsigned jtag_get_speed_khz(void);
708 void jtag_set_verify(bool enable
);
709 bool jtag_will_verify(void);