1 /***************************************************************************
2 * Copyright (C) 2005 by Dominic Rath *
3 * Dominic.Rath@gmx.de *
5 * Copyright (C) 2007-2010 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, see <http://www.gnu.org/licenses/>. *
20 ***************************************************************************/
22 #ifndef OPENOCD_JTAG_JTAG_H
23 #define OPENOCD_JTAG_JTAG_H
25 #include <helper/binarybuffer.h>
26 #include <helper/log.h>
27 #include <helper/replacements.h>
29 #ifndef DEBUG_JTAG_IOZ
30 #define DEBUG_JTAG_IOZ 64
33 /*-----</Macros>-------------------------------------------------*/
36 * Defines JTAG Test Access Port states.
38 * These definitions were gleaned from the ARM7TDMI-S Technical
39 * Reference Manual and validated against several other ARM core
42 * FIXME some interfaces require specific numbers be used, as they
43 * are handed-off directly to their hardware implementations.
44 * Fix those drivers to map as appropriate ... then pick some
45 * sane set of numbers here (where 0/uninitialized == INVALID).
47 typedef enum tap_state
{
50 /* Proper ARM recommended numbers */
70 * Defines arguments for reset functions
72 #define SRST_DEASSERT 0
74 #define TRST_DEASSERT 0
78 * Function tap_state_name
79 * Returns a string suitable for display representing the JTAG tap_state
81 const char *tap_state_name(tap_state_t state
);
83 /** Provides user-friendly name lookup of TAP states. */
84 tap_state_t
tap_state_by_name(const char *name
);
86 /** The current TAP state of the pending JTAG command queue. */
87 extern tap_state_t cmd_queue_cur_state
;
90 * This structure defines a single scan field in the scan. It provides
91 * fields for the field's width and pointers to scan input and output
94 * In addition, this structure includes a value and mask that is used by
95 * jtag_add_dr_scan_check() to validate the value that was scanned out.
98 /** The number of bits this field specifies */
100 /** A pointer to value to be scanned into the device */
101 const uint8_t *out_value
;
102 /** A pointer to a 32-bit memory location for data scanned out */
105 /** The value used to check the data scanned out. */
106 uint8_t *check_value
;
107 /** The mask to go with check_value */
115 int abs_chain_position
;
116 /** Is this TAP disabled after JTAG reset? */
117 bool disabled_after_reset
;
118 /** Is this TAP currently enabled? */
120 int ir_length
; /**< size of instruction register */
121 uint32_t ir_capture_value
;
122 uint8_t *expected
; /**< Capture-IR expected value */
123 uint32_t ir_capture_mask
;
124 uint8_t *expected_mask
; /**< Capture-IR expected mask */
125 uint32_t idcode
; /**< device identification code */
126 /** not all devices have idcode,
127 * we'll discover this during chain examination */
130 /** Array of expected identification codes */
131 uint32_t *expected_ids
;
132 /** Number of expected identification codes */
133 uint8_t expected_ids_cnt
;
135 /** Flag saying whether to ignore version field in expected_ids[] */
138 /** current instruction */
140 /** Bypass register selected */
143 struct jtag_tap_event_action
*event_action
;
145 struct jtag_tap
*next_tap
;
146 /* private pointer to support none-jtag specific functions */
150 void jtag_tap_init(struct jtag_tap
*tap
);
151 void jtag_tap_free(struct jtag_tap
*tap
);
153 struct jtag_tap
*jtag_all_taps(void);
154 const char *jtag_tap_name(const struct jtag_tap
*tap
);
155 struct jtag_tap
*jtag_tap_by_string(const char *dotted_name
);
156 struct jtag_tap
*jtag_tap_by_jim_obj(Jim_Interp
*interp
, Jim_Obj
*obj
);
157 struct jtag_tap
*jtag_tap_by_position(unsigned abs_position
);
158 struct jtag_tap
*jtag_tap_next_enabled(struct jtag_tap
*p
);
159 unsigned jtag_tap_count_enabled(void);
160 unsigned jtag_tap_count(void);
163 * - TRST_ASSERTED triggers two sets of callbacks, after operations to
164 * reset the scan chain -- via TMS+TCK signaling, or deasserting the
165 * nTRST signal -- are queued:
167 * + Callbacks in C code fire first, patching internal state
168 * + Then post-reset event scripts fire ... activating JTAG circuits
169 * via TCK cycles, exiting SWD mode via TMS sequences, etc
171 * During those callbacks, scan chain contents have not been validated.
172 * JTAG operations that address a specific TAP (primarily DR/IR scans)
173 * must *not* be queued.
175 * - TAP_EVENT_SETUP is reported after TRST_ASSERTED, and after the scan
176 * chain has been validated. JTAG operations including scans that
177 * target specific TAPs may be performed.
179 * - TAP_EVENT_ENABLE and TAP_EVENT_DISABLE implement TAP activation and
180 * deactivation outside the core using scripted code that understands
181 * the specific JTAG router type. They might be triggered indirectly
182 * from EVENT_SETUP operations.
186 JTAG_TAP_EVENT_SETUP
,
187 JTAG_TAP_EVENT_ENABLE
,
188 JTAG_TAP_EVENT_DISABLE
,
191 struct jtag_tap_event_action
{
192 /** The event for which this action will be triggered. */
193 enum jtag_event event
;
194 /** The interpreter to use for evaluating the @c body. */
196 /** Contains a script to 'eval' when the @c event is triggered. */
198 /* next action in linked list */
199 struct jtag_tap_event_action
*next
;
203 * Defines the function signature required for JTAG event callback
204 * functions, which are added with jtag_register_event_callback()
205 * and removed jtag_unregister_event_callback().
206 * @param event The event to handle.
207 * @param priv A pointer to data that was passed to
208 * jtag_register_event_callback().
209 * @returns Must return ERROR_OK on success, or an error code on failure.
211 * @todo Change to return void or define a use for its return code.
213 typedef int (*jtag_event_handler_t
)(enum jtag_event event
, void *priv
);
215 int jtag_register_event_callback(jtag_event_handler_t f
, void *x
);
216 int jtag_unregister_event_callback(jtag_event_handler_t f
, void *x
);
218 int jtag_call_event_callbacks(enum jtag_event event
);
222 RESET_HAS_TRST
= 0x1,
223 RESET_HAS_SRST
= 0x2,
224 RESET_TRST_AND_SRST
= 0x3,
225 RESET_SRST_PULLS_TRST
= 0x4,
226 RESET_TRST_PULLS_SRST
= 0x8,
227 RESET_TRST_OPEN_DRAIN
= 0x10,
228 RESET_SRST_PUSH_PULL
= 0x20,
229 RESET_SRST_NO_GATING
= 0x40,
230 RESET_CNCT_UNDER_SRST
= 0x80
233 enum reset_types
jtag_get_reset_config(void);
234 void jtag_set_reset_config(enum reset_types type
);
236 void jtag_set_nsrst_delay(unsigned delay
);
237 unsigned jtag_get_nsrst_delay(void);
239 void jtag_set_ntrst_delay(unsigned delay
);
240 unsigned jtag_get_ntrst_delay(void);
242 void jtag_set_nsrst_assert_width(unsigned delay
);
243 unsigned jtag_get_nsrst_assert_width(void);
245 void jtag_set_ntrst_assert_width(unsigned delay
);
246 unsigned jtag_get_ntrst_assert_width(void);
248 /** @returns The current state of TRST. */
249 int jtag_get_trst(void);
250 /** @returns The current state of SRST. */
251 int jtag_get_srst(void);
253 /** Enable or disable data scan verification checking. */
254 void jtag_set_verify(bool enable
);
255 /** @returns True if data scan verification will be performed. */
256 bool jtag_will_verify(void);
258 /** Enable or disable verification of IR scan checking. */
259 void jtag_set_verify_capture_ir(bool enable
);
260 /** @returns True if IR scan verification will be performed. */
261 bool jtag_will_verify_capture_ir(void);
263 /** Set ms to sleep after jtag_execute_queue() flushes queue. Debug purposes. */
264 void jtag_set_flush_queue_sleep(int ms
);
267 * Initialize JTAG chain using only a RESET reset. If init fails,
270 int jtag_init(struct command_context
*cmd_ctx
);
272 /** reset, then initialize JTAG chain */
273 int jtag_init_reset(struct command_context
*cmd_ctx
);
274 int jtag_register_commands(struct command_context
*cmd_ctx
);
275 int jtag_init_inner(struct command_context
*cmd_ctx
);
279 * The JTAG interface can be implemented with a software or hardware fifo.
281 * TAP_DRSHIFT and TAP_IRSHIFT are illegal end states; however,
282 * TAP_DRSHIFT/IRSHIFT can be emulated as end states, by using longer
285 * Code that is relatively insensitive to the path taken through state
286 * machine (as long as it is JTAG compliant) can use @a endstate for
287 * jtag_add_xxx_scan(). Otherwise, the pause state must be specified as
288 * end state and a subsequent jtag_add_pathmove() must be issued.
292 * Generate an IR SCAN with a list of scan fields with one entry for
295 * If the input field list contains an instruction value for a TAP then
296 * that is used otherwise the TAP is set to bypass.
298 * TAPs for which no fields are passed are marked as bypassed for
299 * subsequent DR SCANs.
302 void jtag_add_ir_scan(struct jtag_tap
*tap
,
303 struct scan_field
*fields
, tap_state_t endstate
);
305 * The same as jtag_add_ir_scan except no verification is performed out
308 void jtag_add_ir_scan_noverify(struct jtag_tap
*tap
,
309 const struct scan_field
*fields
, tap_state_t state
);
311 * Scan out the bits in ir scan mode.
313 * If in_bits == NULL, discard incoming bits.
315 void jtag_add_plain_ir_scan(int num_bits
, const uint8_t *out_bits
, uint8_t *in_bits
,
316 tap_state_t endstate
);
319 * Generate a DR SCAN using the fields passed to the function.
320 * For connected TAPs, the function checks in_fields and uses fields
321 * specified there. For bypassed TAPs, the function generates a dummy
322 * 1-bit field. The bypass status of TAPs is set by jtag_add_ir_scan().
324 void jtag_add_dr_scan(struct jtag_tap
*tap
, int num_fields
,
325 const struct scan_field
*fields
, tap_state_t endstate
);
326 /** A version of jtag_add_dr_scan() that uses the check_value/mask fields */
327 void jtag_add_dr_scan_check(struct jtag_tap
*tap
, int num_fields
,
328 struct scan_field
*fields
, tap_state_t endstate
);
330 * Scan out the bits in ir scan mode.
332 * If in_bits == NULL, discard incoming bits.
334 void jtag_add_plain_dr_scan(int num_bits
,
335 const uint8_t *out_bits
, uint8_t *in_bits
, tap_state_t endstate
);
338 * Defines the type of data passed to the jtag_callback_t interface.
339 * The underlying type must allow storing an @c int or pointer type.
341 typedef intptr_t jtag_callback_data_t
;
344 * Defines a simple JTAG callback that can allow conversions on data
345 * scanned in from an interface.
347 * This callback should only be used for conversion that cannot fail.
348 * For conversion types or checks that can fail, use the more complete
349 * variant: jtag_callback_t.
351 typedef void (*jtag_callback1_t
)(jtag_callback_data_t data0
);
353 /** A simpler version of jtag_add_callback4(). */
354 void jtag_add_callback(jtag_callback1_t f
, jtag_callback_data_t data0
);
358 * Defines the interface of the JTAG callback mechanism. Such
359 * callbacks can be executed once the queue has been flushed.
361 * The JTAG queue can be executed synchronously or asynchronously.
362 * Typically for USB, the queue is executed asynchronously. For
363 * low-latency interfaces, the queue may be executed synchronously.
365 * The callback mechanism is very general and does not make many
366 * assumptions about what the callback does or what its arguments are.
367 * These callbacks are typically executed *after* the *entire* JTAG
368 * queue has been executed for e.g. USB interfaces, and they are
369 * guaranteed to be invoked in the order that they were queued.
371 * If the execution of the queue fails before the callbacks, then --
372 * depending on driver implementation -- the callbacks may or may not be
375 * @todo Make that behavior consistent.
377 * @param data0 Typically used to point to the data to operate on.
378 * Frequently this will be the data clocked in during a shift operation.
379 * @param data1 An integer big enough to use as an @c int or a pointer.
380 * @param data2 An integer big enough to use as an @c int or a pointer.
381 * @param data3 An integer big enough to use as an @c int or a pointer.
382 * @returns an error code
384 typedef int (*jtag_callback_t
)(jtag_callback_data_t data0
,
385 jtag_callback_data_t data1
,
386 jtag_callback_data_t data2
,
387 jtag_callback_data_t data3
);
390 * Run a TAP_RESET reset where the end state is TAP_RESET,
391 * regardless of the start state.
393 void jtag_add_tlr(void);
396 * Application code *must* assume that interfaces will
397 * implement transitions between states with different
398 * paths and path lengths through the state diagram. The
399 * path will vary across interface and also across versions
400 * of the same interface over time. Even if the OpenOCD code
401 * is unchanged, the actual path taken may vary over time
402 * and versions of interface firmware or PCB revisions.
404 * Use jtag_add_pathmove() when specific transition sequences
407 * Do not use jtag_add_pathmove() unless you need to, but do use it
410 * DANGER! If the target is dependent upon a particular sequence
411 * of transitions for things to work correctly(e.g. as a workaround
412 * for an errata that contradicts the JTAG standard), then pathmove
413 * must be used, even if some jtag interfaces happen to use the
414 * desired path. Worse, the jtag interface used for testing a
415 * particular implementation, could happen to use the "desired"
416 * path when transitioning to/from end
419 * A list of unambiguous single clock state transitions, not
420 * all drivers can support this, but it is required for e.g.
421 * XScale and Xilinx support
423 * Note! TAP_RESET must not be used in the path!
425 * Note that the first on the list must be reachable
426 * via a single transition from the current state.
428 * All drivers are required to implement jtag_add_pathmove().
429 * However, if the pathmove sequence can not be precisely
430 * executed, an interface_jtag_add_pathmove() or jtag_execute_queue()
431 * must return an error. It is legal, but not recommended, that
432 * a driver returns an error in all cases for a pathmove if it
433 * can only implement a few transitions and therefore
434 * a partial implementation of pathmove would have little practical
437 * If an error occurs, jtag_error will contain one of these error codes:
438 * - ERROR_JTAG_NOT_STABLE_STATE -- The final state was not stable.
439 * - ERROR_JTAG_STATE_INVALID -- The path passed through TAP_RESET.
440 * - ERROR_JTAG_TRANSITION_INVALID -- The path includes invalid
443 void jtag_add_pathmove(int num_states
, const tap_state_t
*path
);
446 * jtag_add_statemove() moves from the current state to @a goal_state.
448 * @param goal_state The final TAP state.
449 * @return ERROR_OK on success, or an error code on failure.
451 * Moves from the current state to the goal \a state.
452 * Both states must be stable.
454 int jtag_add_statemove(tap_state_t goal_state
);
457 * Goes to TAP_IDLE (if we're not already there), cycle
458 * precisely num_cycles in the TAP_IDLE state, after which move
459 * to @a endstate (unless it is also TAP_IDLE).
461 * @param num_cycles Number of cycles in TAP_IDLE state. This argument
462 * may be 0, in which case this routine will navigate to @a endstate
464 * @param endstate The final state.
466 void jtag_add_runtest(int num_cycles
, tap_state_t endstate
);
469 * A reset of the TAP state machine can be requested.
471 * Whether tms or trst reset is used depends on the capabilities of
472 * the target and jtag interface(reset_config command configures this).
474 * srst can driver a reset of the TAP state machine and vice
477 * Application code may need to examine value of jtag_reset_config
478 * to determine the proper codepath
480 * DANGER! Even though srst drives trst, trst might not be connected to
481 * the interface, and it might actually be *harmful* to assert trst in this case.
483 * This is why combinations such as "reset_config srst_only srst_pulls_trst"
486 * only req_tlr_or_trst and srst can have a transition for a
487 * call as the effects of transitioning both at the "same time"
488 * are undefined, but when srst_pulls_trst or vice versa,
489 * then trst & srst *must* be asserted together.
491 void jtag_add_reset(int req_tlr_or_trst
, int srst
);
493 void jtag_add_sleep(uint32_t us
);
495 int jtag_add_tms_seq(unsigned nbits
, const uint8_t *seq
, enum tap_state t
);
498 * Function jtag_add_clocks
499 * first checks that the state in which the clocks are to be issued is
500 * stable, then queues up num_cycles clocks for transmission.
502 void jtag_add_clocks(int num_cycles
);
505 * For software FIFO implementations, the queued commands can be executed
506 * during this call or earlier. A sw queue might decide to push out
507 * some of the jtag_add_xxx() operations once the queue is "big enough".
509 * This fn will return an error code if any of the prior jtag_add_xxx()
510 * calls caused a failure, e.g. check failure. Note that it does not
511 * matter if the operation was executed *before* jtag_execute_queue(),
512 * jtag_execute_queue() will still return an error code.
514 * All jtag_add_xxx() calls that have in_handler != NULL will have been
515 * executed when this fn returns, but if what has been queued only
516 * clocks data out, without reading anything back, then JTAG could
517 * be running *after* jtag_execute_queue() returns. The API does
518 * not define a way to flush a hw FIFO that runs *after*
519 * jtag_execute_queue() returns.
521 * jtag_add_xxx() commands can either be executed immediately or
522 * at some time between the jtag_add_xxx() fn call and jtag_execute_queue().
524 int jtag_execute_queue(void);
526 /** same as jtag_execute_queue() but does not clear the error flag */
527 void jtag_execute_queue_noclear(void);
529 /** @returns the number of times the scan queue has been flushed */
530 int jtag_get_flush_queue_count(void);
532 /** Report Tcl event to all TAPs */
533 void jtag_notify_event(enum jtag_event
);
535 /* can be implemented by hw + sw */
536 int jtag_power_dropout(int *dropout
);
537 int jtag_srst_asserted(int *srst_asserted
);
539 /* JTAG support functions */
542 * Execute jtag queue and check value with an optional mask.
543 * @param field Pointer to scan field.
544 * @param value Pointer to scan value.
545 * @param mask Pointer to scan mask; may be NULL.
546 * @returns Nothing, but calls jtag_set_error() on any error.
548 void jtag_check_value_mask(struct scan_field
*field
, uint8_t *value
, uint8_t *mask
);
550 void jtag_sleep(uint32_t us
);
553 * The JTAG subsystem defines a number of error codes,
554 * using codes between -100 and -199.
556 #define ERROR_JTAG_INIT_FAILED (-100)
557 #define ERROR_JTAG_INVALID_INTERFACE (-101)
558 #define ERROR_JTAG_NOT_IMPLEMENTED (-102)
559 #define ERROR_JTAG_TRST_ASSERTED (-103)
560 #define ERROR_JTAG_QUEUE_FAILED (-104)
561 #define ERROR_JTAG_NOT_STABLE_STATE (-105)
562 #define ERROR_JTAG_DEVICE_ERROR (-107)
563 #define ERROR_JTAG_STATE_INVALID (-108)
564 #define ERROR_JTAG_TRANSITION_INVALID (-109)
565 #define ERROR_JTAG_INIT_SOFT_FAIL (-110)
568 * Set the current JTAG core execution error, unless one was set
569 * by a previous call previously. Driver or application code must
570 * use jtag_error_clear to reset jtag_error once this routine has been
571 * called with a non-zero error code.
573 void jtag_set_error(int error
);
575 * Resets jtag_error to ERROR_OK, returning its previous value.
576 * @returns The previous value of @c jtag_error.
578 int jtag_error_clear(void);
581 * Return true if it's safe for a background polling task to access the
582 * JTAG scan chain. Polling may be explicitly disallowed, and is also
583 * unsafe while nTRST is active or the JTAG clock is gated off.
585 bool is_jtag_poll_safe(void);
588 * Return flag reporting whether JTAG polling is disallowed.
590 bool jtag_poll_get_enabled(void);
593 * Assign flag reporting whether JTAG polling is disallowed.
595 void jtag_poll_set_enabled(bool value
);
597 #include <jtag/minidriver.h>
599 int jim_jtag_newtap(Jim_Interp
*interp
, int argc
, Jim_Obj
*const *argv
);
601 #endif /* OPENOCD_JTAG_JTAG_H */