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>
28 #ifndef DEBUG_JTAG_IOZ
29 #define DEBUG_JTAG_IOZ 64
32 /*-----</Macros>-------------------------------------------------*/
35 * Defines JTAG Test Access Port states.
37 * These definitions were gleaned from the ARM7TDMI-S Technical
38 * Reference Manual and validated against several other ARM core
41 * FIXME some interfaces require specific numbers be used, as they
42 * are handed-off directly to their hardware implementations.
43 * Fix those drivers to map as appropriate ... then pick some
44 * sane set of numbers here (where 0/uninitialized == INVALID).
46 typedef enum tap_state {
49 /* Proper ARM recommended numbers */
69 * Defines arguments for reset functions
71 #define SRST_DEASSERT 0
73 #define TRST_DEASSERT 0
77 * Function tap_state_name
78 * Returns a string suitable for display representing the JTAG tap_state
80 const char *tap_state_name(tap_state_t state);
82 /** Provides user-friendly name lookup of TAP states. */
83 tap_state_t tap_state_by_name(const char *name);
85 /** The current TAP state of the pending JTAG command queue. */
86 extern tap_state_t cmd_queue_cur_state;
89 * This structure defines a single scan field in the scan. It provides
90 * fields for the field's width and pointers to scan input and output
93 * In addition, this structure includes a value and mask that is used by
94 * jtag_add_dr_scan_check() to validate the value that was scanned out.
97 /** The number of bits this field specifies */
99 /** A pointer to value to be scanned into the device */
100 const uint8_t *out_value;
101 /** A pointer to a 32-bit memory location for data scanned out */
104 /** The value used to check the data scanned out. */
105 uint8_t *check_value;
106 /** The mask to go with check_value */
114 int abs_chain_position;
115 /** Is this TAP disabled after JTAG reset? */
116 bool disabled_after_reset;
117 /** Is this TAP currently enabled? */
119 int ir_length; /**< size of instruction register */
120 uint32_t ir_capture_value;
121 uint8_t *expected; /**< Capture-IR expected value */
122 uint32_t ir_capture_mask;
123 uint8_t *expected_mask; /**< Capture-IR expected mask */
124 uint32_t idcode; /**< device identification code */
125 /** not all devices have idcode,
126 * we'll discover this during chain examination */
129 /** Array of expected identification codes */
130 uint32_t *expected_ids;
131 /** Number of expected identification codes */
132 uint8_t expected_ids_cnt;
134 /** Flag saying whether to ignore version field in expected_ids[] */
137 /** current instruction */
139 /** Bypass register selected */
142 struct jtag_tap_event_action *event_action;
144 struct jtag_tap *next_tap;
145 /* private pointer to support none-jtag specific functions */
149 void jtag_tap_init(struct jtag_tap *tap);
150 void jtag_tap_free(struct jtag_tap *tap);
152 struct jtag_tap *jtag_all_taps(void);
153 const char *jtag_tap_name(const struct jtag_tap *tap);
154 struct jtag_tap *jtag_tap_by_string(const char *dotted_name);
155 struct jtag_tap *jtag_tap_by_jim_obj(Jim_Interp *interp, Jim_Obj *obj);
156 struct jtag_tap *jtag_tap_by_position(unsigned abs_position);
157 struct jtag_tap *jtag_tap_next_enabled(struct jtag_tap *p);
158 unsigned jtag_tap_count_enabled(void);
159 unsigned jtag_tap_count(void);
162 * - TRST_ASSERTED triggers two sets of callbacks, after operations to
163 * reset the scan chain -- via TMS+TCK signaling, or deasserting the
164 * nTRST signal -- are queued:
166 * + Callbacks in C code fire first, patching internal state
167 * + Then post-reset event scripts fire ... activating JTAG circuits
168 * via TCK cycles, exiting SWD mode via TMS sequences, etc
170 * During those callbacks, scan chain contents have not been validated.
171 * JTAG operations that address a specific TAP (primarily DR/IR scans)
172 * must *not* be queued.
174 * - TAP_EVENT_SETUP is reported after TRST_ASSERTED, and after the scan
175 * chain has been validated. JTAG operations including scans that
176 * target specific TAPs may be performed.
178 * - TAP_EVENT_ENABLE and TAP_EVENT_DISABLE implement TAP activation and
179 * deactivation outside the core using scripted code that understands
180 * the specific JTAG router type. They might be triggered indirectly
181 * from EVENT_SETUP operations.
185 JTAG_TAP_EVENT_SETUP,
186 JTAG_TAP_EVENT_ENABLE,
187 JTAG_TAP_EVENT_DISABLE,
190 struct jtag_tap_event_action {
191 /** The event for which this action will be triggered. */
192 enum jtag_event event;
193 /** The interpreter to use for evaluating the @c body. */
195 /** Contains a script to 'eval' when the @c event is triggered. */
197 /* next action in linked list */
198 struct jtag_tap_event_action *next;
202 * Defines the function signature required for JTAG event callback
203 * functions, which are added with jtag_register_event_callback()
204 * and removed jtag_unregister_event_callback().
205 * @param event The event to handle.
206 * @param priv A pointer to data that was passed to
207 * jtag_register_event_callback().
208 * @returns Must return ERROR_OK on success, or an error code on failure.
210 * @todo Change to return void or define a use for its return code.
212 typedef int (*jtag_event_handler_t)(enum jtag_event event, void *priv);
214 int jtag_register_event_callback(jtag_event_handler_t f, void *x);
215 int jtag_unregister_event_callback(jtag_event_handler_t f, void *x);
217 int jtag_call_event_callbacks(enum jtag_event event);
220 /** @returns The current JTAG speed setting. */
221 int jtag_get_speed(int *speed);
224 * Given a @a speed setting, use the interface @c speed_div callback to
225 * adjust the setting.
226 * @param speed The speed setting to convert back to readable KHz.
227 * @returns ERROR_OK if the interface has not been initialized or on success;
228 * otherwise, the error code produced by the @c speed_div callback.
230 int jtag_get_speed_readable(int *speed);
232 /** Attempt to configure the interface for the specified KHz. */
233 int jtag_config_khz(unsigned khz);
236 * Attempt to enable RTCK/RCLK. If that fails, fallback to the
237 * specified frequency.
239 int jtag_config_rclk(unsigned fallback_speed_khz);
241 /** Retrieves the clock speed of the JTAG interface in KHz. */
242 unsigned jtag_get_speed_khz(void);
246 RESET_HAS_TRST = 0x1,
247 RESET_HAS_SRST = 0x2,
248 RESET_TRST_AND_SRST = 0x3,
249 RESET_SRST_PULLS_TRST = 0x4,
250 RESET_TRST_PULLS_SRST = 0x8,
251 RESET_TRST_OPEN_DRAIN = 0x10,
252 RESET_SRST_PUSH_PULL = 0x20,
253 RESET_SRST_NO_GATING = 0x40,
254 RESET_CNCT_UNDER_SRST = 0x80
257 enum reset_types jtag_get_reset_config(void);
258 void jtag_set_reset_config(enum reset_types type);
260 void jtag_set_nsrst_delay(unsigned delay);
261 unsigned jtag_get_nsrst_delay(void);
263 void jtag_set_ntrst_delay(unsigned delay);
264 unsigned jtag_get_ntrst_delay(void);
266 void jtag_set_nsrst_assert_width(unsigned delay);
267 unsigned jtag_get_nsrst_assert_width(void);
269 void jtag_set_ntrst_assert_width(unsigned delay);
270 unsigned jtag_get_ntrst_assert_width(void);
272 /** @returns The current state of TRST. */
273 int jtag_get_trst(void);
274 /** @returns The current state of SRST. */
275 int jtag_get_srst(void);
277 /** Enable or disable data scan verification checking. */
278 void jtag_set_verify(bool enable);
279 /** @returns True if data scan verification will be performed. */
280 bool jtag_will_verify(void);
282 /** Enable or disable verification of IR scan checking. */
283 void jtag_set_verify_capture_ir(bool enable);
284 /** @returns True if IR scan verification will be performed. */
285 bool jtag_will_verify_capture_ir(void);
287 /** Initialize debug adapter upon startup. */
288 int adapter_init(struct command_context *cmd_ctx);
290 /** Shutdown the debug adapter upon program exit. */
291 int adapter_quit(void);
293 /** Set ms to sleep after jtag_execute_queue() flushes queue. Debug purposes. */
294 void jtag_set_flush_queue_sleep(int ms);
297 * Initialize JTAG chain using only a RESET reset. If init fails,
300 int jtag_init(struct command_context *cmd_ctx);
302 /** reset, then initialize JTAG chain */
303 int jtag_init_reset(struct command_context *cmd_ctx);
304 int jtag_register_commands(struct command_context *cmd_ctx);
305 int jtag_init_inner(struct command_context *cmd_ctx);
309 * The JTAG interface can be implemented with a software or hardware fifo.
311 * TAP_DRSHIFT and TAP_IRSHIFT are illegal end states; however,
312 * TAP_DRSHIFT/IRSHIFT can be emulated as end states, by using longer
315 * Code that is relatively insensitive to the path taken through state
316 * machine (as long as it is JTAG compliant) can use @a endstate for
317 * jtag_add_xxx_scan(). Otherwise, the pause state must be specified as
318 * end state and a subsequent jtag_add_pathmove() must be issued.
322 * Generate an IR SCAN with a list of scan fields with one entry for
325 * If the input field list contains an instruction value for a TAP then
326 * that is used otherwise the TAP is set to bypass.
328 * TAPs for which no fields are passed are marked as bypassed for
329 * subsequent DR SCANs.
332 void jtag_add_ir_scan(struct jtag_tap *tap,
333 struct scan_field *fields, tap_state_t endstate);
335 * The same as jtag_add_ir_scan except no verification is performed out
338 void jtag_add_ir_scan_noverify(struct jtag_tap *tap,
339 const struct scan_field *fields, tap_state_t state);
341 * Scan out the bits in ir scan mode.
343 * If in_bits == NULL, discard incoming bits.
345 void jtag_add_plain_ir_scan(int num_bits, const uint8_t *out_bits, uint8_t *in_bits,
346 tap_state_t endstate);
349 * Generate a DR SCAN using the fields passed to the function.
350 * For connected TAPs, the function checks in_fields and uses fields
351 * specified there. For bypassed TAPs, the function generates a dummy
352 * 1-bit field. The bypass status of TAPs is set by jtag_add_ir_scan().
354 void jtag_add_dr_scan(struct jtag_tap *tap, int num_fields,
355 const struct scan_field *fields, tap_state_t endstate);
356 /** A version of jtag_add_dr_scan() that uses the check_value/mask fields */
357 void jtag_add_dr_scan_check(struct jtag_tap *tap, int num_fields,
358 struct scan_field *fields, tap_state_t endstate);
360 * Scan out the bits in ir scan mode.
362 * If in_bits == NULL, discard incoming bits.
364 void jtag_add_plain_dr_scan(int num_bits,
365 const uint8_t *out_bits, uint8_t *in_bits, tap_state_t endstate);
368 * Defines the type of data passed to the jtag_callback_t interface.
369 * The underlying type must allow storing an @c int or pointer type.
371 typedef intptr_t jtag_callback_data_t;
374 * Defines a simple JTAG callback that can allow conversions on data
375 * scanned in from an interface.
377 * This callback should only be used for conversion that cannot fail.
378 * For conversion types or checks that can fail, use the more complete
379 * variant: jtag_callback_t.
381 typedef void (*jtag_callback1_t)(jtag_callback_data_t data0);
383 /** A simpler version of jtag_add_callback4(). */
384 void jtag_add_callback(jtag_callback1_t f, jtag_callback_data_t data0);
388 * Defines the interface of the JTAG callback mechanism. Such
389 * callbacks can be executed once the queue has been flushed.
391 * The JTAG queue can be executed synchronously or asynchronously.
392 * Typically for USB, the queue is executed asynchronously. For
393 * low-latency interfaces, the queue may be executed synchronously.
395 * The callback mechanism is very general and does not make many
396 * assumptions about what the callback does or what its arguments are.
397 * These callbacks are typically executed *after* the *entire* JTAG
398 * queue has been executed for e.g. USB interfaces, and they are
399 * guaranteed to be invoked in the order that they were queued.
401 * If the execution of the queue fails before the callbacks, then --
402 * depending on driver implementation -- the callbacks may or may not be
405 * @todo Make that behavior consistent.
407 * @param data0 Typically used to point to the data to operate on.
408 * Frequently this will be the data clocked in during a shift operation.
409 * @param data1 An integer big enough to use as an @c int or a pointer.
410 * @param data2 An integer big enough to use as an @c int or a pointer.
411 * @param data3 An integer big enough to use as an @c int or a pointer.
412 * @returns an error code
414 typedef int (*jtag_callback_t)(jtag_callback_data_t data0,
415 jtag_callback_data_t data1,
416 jtag_callback_data_t data2,
417 jtag_callback_data_t data3);
420 * Run a TAP_RESET reset where the end state is TAP_RESET,
421 * regardless of the start state.
423 void jtag_add_tlr(void);
426 * Application code *must* assume that interfaces will
427 * implement transitions between states with different
428 * paths and path lengths through the state diagram. The
429 * path will vary across interface and also across versions
430 * of the same interface over time. Even if the OpenOCD code
431 * is unchanged, the actual path taken may vary over time
432 * and versions of interface firmware or PCB revisions.
434 * Use jtag_add_pathmove() when specific transition sequences
437 * Do not use jtag_add_pathmove() unless you need to, but do use it
440 * DANGER! If the target is dependent upon a particular sequence
441 * of transitions for things to work correctly(e.g. as a workaround
442 * for an errata that contradicts the JTAG standard), then pathmove
443 * must be used, even if some jtag interfaces happen to use the
444 * desired path. Worse, the jtag interface used for testing a
445 * particular implementation, could happen to use the "desired"
446 * path when transitioning to/from end
449 * A list of unambiguous single clock state transitions, not
450 * all drivers can support this, but it is required for e.g.
451 * XScale and Xilinx support
453 * Note! TAP_RESET must not be used in the path!
455 * Note that the first on the list must be reachable
456 * via a single transition from the current state.
458 * All drivers are required to implement jtag_add_pathmove().
459 * However, if the pathmove sequence can not be precisely
460 * executed, an interface_jtag_add_pathmove() or jtag_execute_queue()
461 * must return an error. It is legal, but not recommended, that
462 * a driver returns an error in all cases for a pathmove if it
463 * can only implement a few transitions and therefore
464 * a partial implementation of pathmove would have little practical
467 * If an error occurs, jtag_error will contain one of these error codes:
468 * - ERROR_JTAG_NOT_STABLE_STATE -- The final state was not stable.
469 * - ERROR_JTAG_STATE_INVALID -- The path passed through TAP_RESET.
470 * - ERROR_JTAG_TRANSITION_INVALID -- The path includes invalid
473 void jtag_add_pathmove(int num_states, const tap_state_t *path);
476 * jtag_add_statemove() moves from the current state to @a goal_state.
478 * @param goal_state The final TAP state.
479 * @return ERROR_OK on success, or an error code on failure.
481 * Moves from the current state to the goal \a state.
482 * Both states must be stable.
484 int jtag_add_statemove(tap_state_t goal_state);
487 * Goes to TAP_IDLE (if we're not already there), cycle
488 * precisely num_cycles in the TAP_IDLE state, after which move
489 * to @a endstate (unless it is also TAP_IDLE).
491 * @param num_cycles Number of cycles in TAP_IDLE state. This argument
492 * may be 0, in which case this routine will navigate to @a endstate
494 * @param endstate The final state.
496 void jtag_add_runtest(int num_cycles, tap_state_t endstate);
499 * A reset of the TAP state machine can be requested.
501 * Whether tms or trst reset is used depends on the capabilities of
502 * the target and jtag interface(reset_config command configures this).
504 * srst can driver a reset of the TAP state machine and vice
507 * Application code may need to examine value of jtag_reset_config
508 * to determine the proper codepath
510 * DANGER! Even though srst drives trst, trst might not be connected to
511 * the interface, and it might actually be *harmful* to assert trst in this case.
513 * This is why combinations such as "reset_config srst_only srst_pulls_trst"
516 * only req_tlr_or_trst and srst can have a transition for a
517 * call as the effects of transitioning both at the "same time"
518 * are undefined, but when srst_pulls_trst or vice versa,
519 * then trst & srst *must* be asserted together.
521 void jtag_add_reset(int req_tlr_or_trst, int srst);
523 void jtag_add_sleep(uint32_t us);
525 int jtag_add_tms_seq(unsigned nbits, const uint8_t *seq, enum tap_state t);
528 * Function jtag_add_clocks
529 * first checks that the state in which the clocks are to be issued is
530 * stable, then queues up num_cycles clocks for transmission.
532 void jtag_add_clocks(int num_cycles);
535 * For software FIFO implementations, the queued commands can be executed
536 * during this call or earlier. A sw queue might decide to push out
537 * some of the jtag_add_xxx() operations once the queue is "big enough".
539 * This fn will return an error code if any of the prior jtag_add_xxx()
540 * calls caused a failure, e.g. check failure. Note that it does not
541 * matter if the operation was executed *before* jtag_execute_queue(),
542 * jtag_execute_queue() will still return an error code.
544 * All jtag_add_xxx() calls that have in_handler != NULL will have been
545 * executed when this fn returns, but if what has been queued only
546 * clocks data out, without reading anything back, then JTAG could
547 * be running *after* jtag_execute_queue() returns. The API does
548 * not define a way to flush a hw FIFO that runs *after*
549 * jtag_execute_queue() returns.
551 * jtag_add_xxx() commands can either be executed immediately or
552 * at some time between the jtag_add_xxx() fn call and jtag_execute_queue().
554 int jtag_execute_queue(void);
556 /** same as jtag_execute_queue() but does not clear the error flag */
557 void jtag_execute_queue_noclear(void);
559 /** @returns the number of times the scan queue has been flushed */
560 int jtag_get_flush_queue_count(void);
562 /** Report Tcl event to all TAPs */
563 void jtag_notify_event(enum jtag_event);
565 /* can be implemented by hw + sw */
566 int jtag_power_dropout(int *dropout);
567 int jtag_srst_asserted(int *srst_asserted);
569 /* JTAG support functions */
572 * Execute jtag queue and check value with an optional mask.
573 * @param field Pointer to scan field.
574 * @param value Pointer to scan value.
575 * @param mask Pointer to scan mask; may be NULL.
576 * @returns Nothing, but calls jtag_set_error() on any error.
578 void jtag_check_value_mask(struct scan_field *field, uint8_t *value, uint8_t *mask);
580 void jtag_sleep(uint32_t us);
583 * The JTAG subsystem defines a number of error codes,
584 * using codes between -100 and -199.
586 #define ERROR_JTAG_INIT_FAILED (-100)
587 #define ERROR_JTAG_INVALID_INTERFACE (-101)
588 #define ERROR_JTAG_NOT_IMPLEMENTED (-102)
589 #define ERROR_JTAG_TRST_ASSERTED (-103)
590 #define ERROR_JTAG_QUEUE_FAILED (-104)
591 #define ERROR_JTAG_NOT_STABLE_STATE (-105)
592 #define ERROR_JTAG_DEVICE_ERROR (-107)
593 #define ERROR_JTAG_STATE_INVALID (-108)
594 #define ERROR_JTAG_TRANSITION_INVALID (-109)
595 #define ERROR_JTAG_INIT_SOFT_FAIL (-110)
598 * Set the current JTAG core execution error, unless one was set
599 * by a previous call previously. Driver or application code must
600 * use jtag_error_clear to reset jtag_error once this routine has been
601 * called with a non-zero error code.
603 void jtag_set_error(int error);
605 * Resets jtag_error to ERROR_OK, returning its previous value.
606 * @returns The previous value of @c jtag_error.
608 int jtag_error_clear(void);
611 * Return true if it's safe for a background polling task to access the
612 * JTAG scan chain. Polling may be explicitly disallowed, and is also
613 * unsafe while nTRST is active or the JTAG clock is gated off.
615 bool is_jtag_poll_safe(void);
618 * Return flag reporting whether JTAG polling is disallowed.
620 bool jtag_poll_get_enabled(void);
623 * Assign flag reporting whether JTAG polling is disallowed.
625 void jtag_poll_set_enabled(bool value);
628 /* The minidriver may have inline versions of some of the low
629 * level APIs that are used in inner loops. */
630 #include <jtag/minidriver.h>
632 int jim_jtag_newtap(Jim_Interp *interp, int argc, Jim_Obj *const *argv);
634 #endif /* OPENOCD_JTAG_JTAG_H */