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 /** Flag saying whether to ignore the bypass bit in the code */
141 /** current instruction */
143 /** Bypass register selected */
146 struct jtag_tap_event_action *event_action;
148 struct jtag_tap *next_tap;
149 /* private pointer to support none-jtag specific functions */
153 void jtag_tap_init(struct jtag_tap *tap);
154 void jtag_tap_free(struct jtag_tap *tap);
156 struct jtag_tap *jtag_all_taps(void);
157 const char *jtag_tap_name(const struct jtag_tap *tap);
158 struct jtag_tap *jtag_tap_by_string(const char *dotted_name);
159 struct jtag_tap *jtag_tap_by_jim_obj(Jim_Interp *interp, Jim_Obj *obj);
160 struct jtag_tap *jtag_tap_by_position(unsigned abs_position);
161 struct jtag_tap *jtag_tap_next_enabled(struct jtag_tap *p);
162 unsigned jtag_tap_count_enabled(void);
163 unsigned jtag_tap_count(void);
166 * - TRST_ASSERTED triggers two sets of callbacks, after operations to
167 * reset the scan chain -- via TMS+TCK signaling, or deasserting the
168 * nTRST signal -- are queued:
170 * + Callbacks in C code fire first, patching internal state
171 * + Then post-reset event scripts fire ... activating JTAG circuits
172 * via TCK cycles, exiting SWD mode via TMS sequences, etc
174 * During those callbacks, scan chain contents have not been validated.
175 * JTAG operations that address a specific TAP (primarily DR/IR scans)
176 * must *not* be queued.
178 * - TAP_EVENT_SETUP is reported after TRST_ASSERTED, and after the scan
179 * chain has been validated. JTAG operations including scans that
180 * target specific TAPs may be performed.
182 * - TAP_EVENT_ENABLE and TAP_EVENT_DISABLE implement TAP activation and
183 * deactivation outside the core using scripted code that understands
184 * the specific JTAG router type. They might be triggered indirectly
185 * from EVENT_SETUP operations.
189 JTAG_TAP_EVENT_SETUP,
190 JTAG_TAP_EVENT_ENABLE,
191 JTAG_TAP_EVENT_DISABLE,
194 struct jtag_tap_event_action {
195 /** The event for which this action will be triggered. */
196 enum jtag_event event;
197 /** The interpreter to use for evaluating the @c body. */
199 /** Contains a script to 'eval' when the @c event is triggered. */
201 /* next action in linked list */
202 struct jtag_tap_event_action *next;
206 * Defines the function signature required for JTAG event callback
207 * functions, which are added with jtag_register_event_callback()
208 * and removed jtag_unregister_event_callback().
209 * @param event The event to handle.
210 * @param priv A pointer to data that was passed to
211 * jtag_register_event_callback().
212 * @returns Must return ERROR_OK on success, or an error code on failure.
214 * @todo Change to return void or define a use for its return code.
216 typedef int (*jtag_event_handler_t)(enum jtag_event event, void *priv);
218 int jtag_register_event_callback(jtag_event_handler_t f, void *x);
219 int jtag_unregister_event_callback(jtag_event_handler_t f, void *x);
221 int jtag_call_event_callbacks(enum jtag_event event);
225 RESET_HAS_TRST = 0x1,
226 RESET_HAS_SRST = 0x2,
227 RESET_TRST_AND_SRST = 0x3,
228 RESET_SRST_PULLS_TRST = 0x4,
229 RESET_TRST_PULLS_SRST = 0x8,
230 RESET_TRST_OPEN_DRAIN = 0x10,
231 RESET_SRST_PUSH_PULL = 0x20,
232 RESET_SRST_NO_GATING = 0x40,
233 RESET_CNCT_UNDER_SRST = 0x80
236 enum reset_types jtag_get_reset_config(void);
237 void jtag_set_reset_config(enum reset_types type);
239 void jtag_set_nsrst_delay(unsigned delay);
240 unsigned jtag_get_nsrst_delay(void);
242 void jtag_set_ntrst_delay(unsigned delay);
243 unsigned jtag_get_ntrst_delay(void);
245 void jtag_set_nsrst_assert_width(unsigned delay);
246 unsigned jtag_get_nsrst_assert_width(void);
248 void jtag_set_ntrst_assert_width(unsigned delay);
249 unsigned jtag_get_ntrst_assert_width(void);
251 /** @returns The current state of TRST. */
252 int jtag_get_trst(void);
253 /** @returns The current state of SRST. */
254 int jtag_get_srst(void);
256 /** Enable or disable data scan verification checking. */
257 void jtag_set_verify(bool enable);
258 /** @returns True if data scan verification will be performed. */
259 bool jtag_will_verify(void);
261 /** Enable or disable verification of IR scan checking. */
262 void jtag_set_verify_capture_ir(bool enable);
263 /** @returns True if IR scan verification will be performed. */
264 bool jtag_will_verify_capture_ir(void);
266 /** Set ms to sleep after jtag_execute_queue() flushes queue. Debug purposes. */
267 void jtag_set_flush_queue_sleep(int ms);
270 * Initialize JTAG chain using only a RESET reset. If init fails,
273 int jtag_init(struct command_context *cmd_ctx);
275 /** reset, then initialize JTAG chain */
276 int jtag_init_reset(struct command_context *cmd_ctx);
277 int jtag_register_commands(struct command_context *cmd_ctx);
278 int jtag_init_inner(struct command_context *cmd_ctx);
282 * The JTAG interface can be implemented with a software or hardware fifo.
284 * TAP_DRSHIFT and TAP_IRSHIFT are illegal end states; however,
285 * TAP_DRSHIFT/IRSHIFT can be emulated as end states, by using longer
288 * Code that is relatively insensitive to the path taken through state
289 * machine (as long as it is JTAG compliant) can use @a endstate for
290 * jtag_add_xxx_scan(). Otherwise, the pause state must be specified as
291 * end state and a subsequent jtag_add_pathmove() must be issued.
295 * Generate an IR SCAN with a list of scan fields with one entry for
298 * If the input field list contains an instruction value for a TAP then
299 * that is used otherwise the TAP is set to bypass.
301 * TAPs for which no fields are passed are marked as bypassed for
302 * subsequent DR SCANs.
305 void jtag_add_ir_scan(struct jtag_tap *tap,
306 struct scan_field *fields, tap_state_t endstate);
308 * The same as jtag_add_ir_scan except no verification is performed out
311 void jtag_add_ir_scan_noverify(struct jtag_tap *tap,
312 const struct scan_field *fields, tap_state_t state);
314 * Scan out the bits in ir scan mode.
316 * If in_bits == NULL, discard incoming bits.
318 void jtag_add_plain_ir_scan(int num_bits, const uint8_t *out_bits, uint8_t *in_bits,
319 tap_state_t endstate);
322 * Generate a DR SCAN using the fields passed to the function.
323 * For connected TAPs, the function checks in_fields and uses fields
324 * specified there. For bypassed TAPs, the function generates a dummy
325 * 1-bit field. The bypass status of TAPs is set by jtag_add_ir_scan().
327 void jtag_add_dr_scan(struct jtag_tap *tap, int num_fields,
328 const struct scan_field *fields, tap_state_t endstate);
329 /** A version of jtag_add_dr_scan() that uses the check_value/mask fields */
330 void jtag_add_dr_scan_check(struct jtag_tap *tap, int num_fields,
331 struct scan_field *fields, tap_state_t endstate);
333 * Scan out the bits in ir scan mode.
335 * If in_bits == NULL, discard incoming bits.
337 void jtag_add_plain_dr_scan(int num_bits,
338 const uint8_t *out_bits, uint8_t *in_bits, tap_state_t endstate);
341 * Defines the type of data passed to the jtag_callback_t interface.
342 * The underlying type must allow storing an @c int or pointer type.
344 typedef intptr_t jtag_callback_data_t;
347 * Defines a simple JTAG callback that can allow conversions on data
348 * scanned in from an interface.
350 * This callback should only be used for conversion that cannot fail.
351 * For conversion types or checks that can fail, use the more complete
352 * variant: jtag_callback_t.
354 typedef void (*jtag_callback1_t)(jtag_callback_data_t data0);
356 /** A simpler version of jtag_add_callback4(). */
357 void jtag_add_callback(jtag_callback1_t f, jtag_callback_data_t data0);
361 * Defines the interface of the JTAG callback mechanism. Such
362 * callbacks can be executed once the queue has been flushed.
364 * The JTAG queue can be executed synchronously or asynchronously.
365 * Typically for USB, the queue is executed asynchronously. For
366 * low-latency interfaces, the queue may be executed synchronously.
368 * The callback mechanism is very general and does not make many
369 * assumptions about what the callback does or what its arguments are.
370 * These callbacks are typically executed *after* the *entire* JTAG
371 * queue has been executed for e.g. USB interfaces, and they are
372 * guaranteed to be invoked in the order that they were queued.
374 * If the execution of the queue fails before the callbacks, then --
375 * depending on driver implementation -- the callbacks may or may not be
378 * @todo Make that behavior consistent.
380 * @param data0 Typically used to point to the data to operate on.
381 * Frequently this will be the data clocked in during a shift operation.
382 * @param data1 An integer big enough to use as an @c int or a pointer.
383 * @param data2 An integer big enough to use as an @c int or a pointer.
384 * @param data3 An integer big enough to use as an @c int or a pointer.
385 * @returns an error code
387 typedef int (*jtag_callback_t)(jtag_callback_data_t data0,
388 jtag_callback_data_t data1,
389 jtag_callback_data_t data2,
390 jtag_callback_data_t data3);
393 * Run a TAP_RESET reset where the end state is TAP_RESET,
394 * regardless of the start state.
396 void jtag_add_tlr(void);
399 * Application code *must* assume that interfaces will
400 * implement transitions between states with different
401 * paths and path lengths through the state diagram. The
402 * path will vary across interface and also across versions
403 * of the same interface over time. Even if the OpenOCD code
404 * is unchanged, the actual path taken may vary over time
405 * and versions of interface firmware or PCB revisions.
407 * Use jtag_add_pathmove() when specific transition sequences
410 * Do not use jtag_add_pathmove() unless you need to, but do use it
413 * DANGER! If the target is dependent upon a particular sequence
414 * of transitions for things to work correctly(e.g. as a workaround
415 * for an errata that contradicts the JTAG standard), then pathmove
416 * must be used, even if some jtag interfaces happen to use the
417 * desired path. Worse, the jtag interface used for testing a
418 * particular implementation, could happen to use the "desired"
419 * path when transitioning to/from end
422 * A list of unambiguous single clock state transitions, not
423 * all drivers can support this, but it is required for e.g.
424 * XScale and Xilinx support
426 * Note! TAP_RESET must not be used in the path!
428 * Note that the first on the list must be reachable
429 * via a single transition from the current state.
431 * All drivers are required to implement jtag_add_pathmove().
432 * However, if the pathmove sequence can not be precisely
433 * executed, an interface_jtag_add_pathmove() or jtag_execute_queue()
434 * must return an error. It is legal, but not recommended, that
435 * a driver returns an error in all cases for a pathmove if it
436 * can only implement a few transitions and therefore
437 * a partial implementation of pathmove would have little practical
440 * If an error occurs, jtag_error will contain one of these error codes:
441 * - ERROR_JTAG_NOT_STABLE_STATE -- The final state was not stable.
442 * - ERROR_JTAG_STATE_INVALID -- The path passed through TAP_RESET.
443 * - ERROR_JTAG_TRANSITION_INVALID -- The path includes invalid
446 void jtag_add_pathmove(int num_states, const tap_state_t *path);
449 * jtag_add_statemove() moves from the current state to @a goal_state.
451 * @param goal_state The final TAP state.
452 * @return ERROR_OK on success, or an error code on failure.
454 * Moves from the current state to the goal \a state.
455 * Both states must be stable.
457 int jtag_add_statemove(tap_state_t goal_state);
460 * Goes to TAP_IDLE (if we're not already there), cycle
461 * precisely num_cycles in the TAP_IDLE state, after which move
462 * to @a endstate (unless it is also TAP_IDLE).
464 * @param num_cycles Number of cycles in TAP_IDLE state. This argument
465 * may be 0, in which case this routine will navigate to @a endstate
467 * @param endstate The final state.
469 void jtag_add_runtest(int num_cycles, tap_state_t endstate);
472 * A reset of the TAP state machine can be requested.
474 * Whether tms or trst reset is used depends on the capabilities of
475 * the target and jtag interface(reset_config command configures this).
477 * srst can driver a reset of the TAP state machine and vice
480 * Application code may need to examine value of jtag_reset_config
481 * to determine the proper codepath
483 * DANGER! Even though srst drives trst, trst might not be connected to
484 * the interface, and it might actually be *harmful* to assert trst in this case.
486 * This is why combinations such as "reset_config srst_only srst_pulls_trst"
489 * only req_tlr_or_trst and srst can have a transition for a
490 * call as the effects of transitioning both at the "same time"
491 * are undefined, but when srst_pulls_trst or vice versa,
492 * then trst & srst *must* be asserted together.
494 void jtag_add_reset(int req_tlr_or_trst, int srst);
496 void jtag_add_sleep(uint32_t us);
498 int jtag_add_tms_seq(unsigned nbits, const uint8_t *seq, enum tap_state t);
501 * Function jtag_add_clocks
502 * first checks that the state in which the clocks are to be issued is
503 * stable, then queues up num_cycles clocks for transmission.
505 void jtag_add_clocks(int num_cycles);
508 * For software FIFO implementations, the queued commands can be executed
509 * during this call or earlier. A sw queue might decide to push out
510 * some of the jtag_add_xxx() operations once the queue is "big enough".
512 * This fn will return an error code if any of the prior jtag_add_xxx()
513 * calls caused a failure, e.g. check failure. Note that it does not
514 * matter if the operation was executed *before* jtag_execute_queue(),
515 * jtag_execute_queue() will still return an error code.
517 * All jtag_add_xxx() calls that have in_handler != NULL will have been
518 * executed when this fn returns, but if what has been queued only
519 * clocks data out, without reading anything back, then JTAG could
520 * be running *after* jtag_execute_queue() returns. The API does
521 * not define a way to flush a hw FIFO that runs *after*
522 * jtag_execute_queue() returns.
524 * jtag_add_xxx() commands can either be executed immediately or
525 * at some time between the jtag_add_xxx() fn call and jtag_execute_queue().
527 int jtag_execute_queue(void);
529 /** same as jtag_execute_queue() but does not clear the error flag */
530 void jtag_execute_queue_noclear(void);
532 /** @returns the number of times the scan queue has been flushed */
533 int jtag_get_flush_queue_count(void);
535 /** Report Tcl event to all TAPs */
536 void jtag_notify_event(enum jtag_event);
538 /* can be implemented by hw + sw */
539 int jtag_power_dropout(int *dropout);
540 int jtag_srst_asserted(int *srst_asserted);
542 /* JTAG support functions */
545 * Execute jtag queue and check value with an optional mask.
546 * @param field Pointer to scan field.
547 * @param value Pointer to scan value.
548 * @param mask Pointer to scan mask; may be NULL.
549 * @returns Nothing, but calls jtag_set_error() on any error.
551 void jtag_check_value_mask(struct scan_field *field, uint8_t *value, uint8_t *mask);
553 void jtag_sleep(uint32_t us);
556 * The JTAG subsystem defines a number of error codes,
557 * using codes between -100 and -199.
559 #define ERROR_JTAG_INIT_FAILED (-100)
560 #define ERROR_JTAG_INVALID_INTERFACE (-101)
561 #define ERROR_JTAG_NOT_IMPLEMENTED (-102)
562 #define ERROR_JTAG_TRST_ASSERTED (-103)
563 #define ERROR_JTAG_QUEUE_FAILED (-104)
564 #define ERROR_JTAG_NOT_STABLE_STATE (-105)
565 #define ERROR_JTAG_DEVICE_ERROR (-107)
566 #define ERROR_JTAG_STATE_INVALID (-108)
567 #define ERROR_JTAG_TRANSITION_INVALID (-109)
568 #define ERROR_JTAG_INIT_SOFT_FAIL (-110)
571 * Set the current JTAG core execution error, unless one was set
572 * by a previous call previously. Driver or application code must
573 * use jtag_error_clear to reset jtag_error once this routine has been
574 * called with a non-zero error code.
576 void jtag_set_error(int error);
578 * Resets jtag_error to ERROR_OK, returning its previous value.
579 * @returns The previous value of @c jtag_error.
581 int jtag_error_clear(void);
584 * Return true if it's safe for a background polling task to access the
585 * JTAG scan chain. Polling may be explicitly disallowed, and is also
586 * unsafe while nTRST is active or the JTAG clock is gated off.
588 bool is_jtag_poll_safe(void);
591 * Return flag reporting whether JTAG polling is disallowed.
593 bool jtag_poll_get_enabled(void);
596 * Assign flag reporting whether JTAG polling is disallowed.
598 void jtag_poll_set_enabled(bool value);
600 #include <jtag/minidriver.h>
602 int jim_jtag_newtap(Jim_Interp *interp, int argc, Jim_Obj *const *argv);
604 #endif /* OPENOCD_JTAG_JTAG_H */