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_AllTaps(void);
179 extern jtag_tap_t* jtag_TapByPosition(int n);
180 extern jtag_tap_t* jtag_TapByString(const char* dotted_name);
181 extern jtag_tap_t* jtag_TapByJimObj(Jim_Interp* interp, Jim_Obj* obj);
182 extern jtag_tap_t* jtag_TapByAbsPosition(int abs_position);
183 extern int jtag_NumEnabledTaps(void);
184 extern int jtag_NumTotalTaps(void);
186 static __inline__ jtag_tap_t* jtag_NextEnabledTap(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.
311 extern void jtag_add_ir_scan(int num_fields, scan_field_t* fields, tap_state_t endstate);
313 * The same as jtag_add_ir_scan except no verification is performed out
316 extern void jtag_add_ir_scan_noverify(int num_fields, const scan_field_t *fields, tap_state_t state);
320 * Set in_value to point to 32 bits of memory to scan into. This
321 * function is a way to handle the case of synchronous and asynchronous
324 * In the event of an asynchronous queue execution the queue buffer
325 * allocation method is used, for the synchronous case the temporary 32
326 * bits come from the input field itself.
328 extern void jtag_alloc_in_value32(scan_field_t *field);
330 extern void jtag_add_dr_scan(int num_fields, const scan_field_t* fields, tap_state_t endstate);
331 /// A version of jtag_add_dr_scan() that uses the check_value/mask fields
332 extern void jtag_add_dr_scan_check(int num_fields, scan_field_t* fields, tap_state_t endstate);
333 extern void jtag_add_plain_ir_scan(int num_fields, const scan_field_t* fields, tap_state_t endstate);
334 extern void jtag_add_plain_dr_scan(int num_fields, const scan_field_t* fields, tap_state_t endstate);
338 * Defines a simple JTAG callback that can allow conversions on data
339 * scanned in from an interface.
341 * This callback should only be used for conversion that cannot fail.
342 * For conversion types or checks that can fail, use the more complete
343 * variant: jtag_callback_t.
345 typedef void (*jtag_callback1_t)(u8 *in);
347 /// A simpler version of jtag_add_callback4().
348 extern void jtag_add_callback(jtag_callback1_t, u8 *in);
352 * Defines the type of data passed to the jtag_callback_t interface.
353 * The underlying type must allow storing an @c int or pointer type.
355 typedef intptr_t jtag_callback_data_t;
358 * Defines the interface of the JTAG callback mechanism.
360 * @param in the pointer to the data clocked in
361 * @param data1 An integer big enough to use as an @c int or a pointer.
362 * @param data2 An integer big enough to use as an @c int or a pointer.
363 * @param data3 An integer big enough to use as an @c int or a pointer.
364 * @returns an error code
366 typedef int (*jtag_callback_t)(u8 *in, jtag_callback_data_t data1, jtag_callback_data_t data2, jtag_callback_data_t data3);
370 * This callback can be executed immediately the queue has been flushed.
372 * The JTAG queue can be executed synchronously or asynchronously.
373 * Typically for USB, the queue is executed asynchronously. For
374 * low-latency interfaces, the queue may be executed synchronously.
376 * The callback mechanism is very general and does not make many
377 * assumptions about what the callback does or what its arguments are.
378 * These callbacks are typically executed *after* the *entire* JTAG
379 * queue has been executed for e.g. USB interfaces, and they are
380 * guaranteeed to be invoked in the order that they were queued.
382 * If the execution of the queue fails before the callbacks, then --
383 * depending on driver implementation -- the callbacks may or may not be
384 * invoked. @todo Can we make this behavior consistent?
386 * The strange name is due to C's lack of overloading using function
389 * @param f The callback function to add.
390 * @param in Typically used to point to the data to operate on.
391 * Frequently this will be the data clocked in during a shift operation.
392 * @param data1 An integer big enough to use as an @c int or a pointer.
393 * @param data2 An integer big enough to use as an @c int or a pointer.
394 * @param data3 An integer big enough to use as an @c int or a pointer.
397 extern void jtag_add_callback4(jtag_callback_t f, u8 *in,
398 jtag_callback_data_t data1, jtag_callback_data_t data2,
399 jtag_callback_data_t data3);
403 * Run a TAP_RESET reset where the end state is TAP_RESET,
404 * regardless of the start state.
406 extern void jtag_add_tlr(void);
409 * Application code *must* assume that interfaces will
410 * implement transitions between states with different
411 * paths and path lengths through the state diagram. The
412 * path will vary across interface and also across versions
413 * of the same interface over time. Even if the OpenOCD code
414 * is unchanged, the actual path taken may vary over time
415 * and versions of interface firmware or PCB revisions.
417 * Use jtag_add_pathmove() when specific transition sequences
420 * Do not use jtag_add_pathmove() unless you need to, but do use it
423 * DANGER! If the target is dependent upon a particular sequence
424 * of transitions for things to work correctly(e.g. as a workaround
425 * for an errata that contradicts the JTAG standard), then pathmove
426 * must be used, even if some jtag interfaces happen to use the
427 * desired path. Worse, the jtag interface used for testing a
428 * particular implementation, could happen to use the "desired"
429 * path when transitioning to/from end
432 * A list of unambigious single clock state transitions, not
433 * all drivers can support this, but it is required for e.g.
434 * XScale and Xilinx support
436 * Note! TAP_RESET must not be used in the path!
438 * Note that the first on the list must be reachable
439 * via a single transition from the current state.
441 * All drivers are required to implement jtag_add_pathmove().
442 * However, if the pathmove sequence can not be precisely
443 * executed, an interface_jtag_add_pathmove() or jtag_execute_queue()
444 * must return an error. It is legal, but not recommended, that
445 * a driver returns an error in all cases for a pathmove if it
446 * can only implement a few transitions and therefore
447 * a partial implementation of pathmove would have little practical
450 extern void jtag_add_pathmove(int num_states, const tap_state_t* path);
453 * Goes to TAP_IDLE (if we're not already there), cycle
454 * precisely num_cycles in the TAP_IDLE state, after which move
455 * to @a endstate (unless it is also TAP_IDLE).
457 * @param num_cycles Number of cycles in TAP_IDLE state. This argument
458 * may be 0, in which case this routine will navigate to @a endstate
460 * @param endstate The final state.
462 extern void jtag_add_runtest(int num_cycles, tap_state_t endstate);
465 * A reset of the TAP state machine can be requested.
467 * Whether tms or trst reset is used depends on the capabilities of
468 * the target and jtag interface(reset_config command configures this).
470 * srst can driver a reset of the TAP state machine and vice
473 * Application code may need to examine value of jtag_reset_config
474 * to determine the proper codepath
476 * DANGER! Even though srst drives trst, trst might not be connected to
477 * the interface, and it might actually be *harmful* to assert trst in this case.
479 * This is why combinations such as "reset_config srst_only srst_pulls_trst"
482 * only req_tlr_or_trst and srst can have a transition for a
483 * call as the effects of transitioning both at the "same time"
484 * are undefined, but when srst_pulls_trst or vice versa,
485 * then trst & srst *must* be asserted together.
487 extern void jtag_add_reset(int req_tlr_or_trst, int srst);
491 * Function jtag_add_end_state
493 * Set a global variable to \a state if \a state != TAP_INVALID.
495 * Return the value of the global variable.
498 extern tap_state_t jtag_add_end_state(tap_state_t state);
500 * Function jtag_get_end_state
502 * Return the value of the global variable for end state
505 extern tap_state_t jtag_get_end_state(void);
506 extern void jtag_add_sleep(u32 us);
510 * Function jtag_add_stable_clocks
511 * first checks that the state in which the clocks are to be issued is
512 * stable, then queues up clock_count clocks for transmission.
514 void jtag_add_clocks(int num_cycles);
518 * For software FIFO implementations, the queued commands can be executed
519 * during this call or earlier. A sw queue might decide to push out
520 * some of the jtag_add_xxx() operations once the queue is "big enough".
522 * This fn will return an error code if any of the prior jtag_add_xxx()
523 * calls caused a failure, e.g. check failure. Note that it does not
524 * matter if the operation was executed *before* jtag_execute_queue(),
525 * jtag_execute_queue() will still return an error code.
527 * All jtag_add_xxx() calls that have in_handler!=NULL will have been
528 * executed when this fn returns, but if what has been queued only
529 * clocks data out, without reading anything back, then JTAG could
530 * be running *after* jtag_execute_queue() returns. The API does
531 * not define a way to flush a hw FIFO that runs *after*
532 * jtag_execute_queue() returns.
534 * jtag_add_xxx() commands can either be executed immediately or
535 * at some time between the jtag_add_xxx() fn call and jtag_execute_queue().
537 extern int jtag_execute_queue(void);
539 /* same as jtag_execute_queue() but does not clear the error flag */
540 extern void jtag_execute_queue_noclear(void);
543 * The jtag_error variable is set when an error occurs while executing
546 * This flag can also be set from application code, if an error happens
547 * during processing that should be reported during jtag_execute_queue().
549 * It is cleared by jtag_execute_queue().
551 extern int jtag_error;
553 static __inline__ void jtag_set_error(int error)
555 if ((error==ERROR_OK)||(jtag_error!=ERROR_OK))
557 /* keep first error */
565 /* can be implemented by hw+sw */
566 extern int jtag_power_dropout(int* dropout);
567 extern 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 extern void jtag_check_value_mask(scan_field_t *field, u8 *value, u8 *mask);
580 extern void jtag_sleep(u32 us);
581 extern int jtag_call_event_callbacks(enum jtag_event event);
582 extern int jtag_register_event_callback(int (* callback)(enum jtag_event event, void* priv), void* priv);
584 extern int jtag_verify_capture_ir;
586 void jtag_tap_handle_event(jtag_tap_t* tap, enum jtag_tap_event e);
589 * The JTAG subsystem defines a number of error codes,
590 * using codes between -100 and -199.
592 #define ERROR_JTAG_INIT_FAILED (-100)
593 #define ERROR_JTAG_INVALID_INTERFACE (-101)
594 #define ERROR_JTAG_NOT_IMPLEMENTED (-102)
595 #define ERROR_JTAG_TRST_ASSERTED (-103)
596 #define ERROR_JTAG_QUEUE_FAILED (-104)
597 #define ERROR_JTAG_NOT_STABLE_STATE (-105)
598 #define ERROR_JTAG_DEVICE_ERROR (-107)
601 * jtag_add_dr_out() is a version of jtag_add_dr_scan() which
602 * only scans data out. It operates on 32 bit integers instead
603 * of 8 bit, which makes it a better impedance match with
604 * the calling code which often operate on 32 bit integers.
606 * Current or end_state can not be TAP_RESET. end_state can be TAP_INVALID
608 * num_bits[i] is the number of bits to clock out from value[i] LSB first.
610 * If the device is in bypass, then that is an error condition in
611 * the caller code that is not detected by this fn, whereas
612 * jtag_add_dr_scan() does detect it. Similarly if the device is not in
613 * bypass, data must be passed to it.
615 * If anything fails, then jtag_error will be set and jtag_execute() will
616 * return an error. There is no way to determine if there was a failure
617 * during this function call.
619 * This is an inline fn to speed up embedded hosts. Also note that
620 * interface_jtag_add_dr_out() can be a *small* inline function for
623 * There is no jtag_add_dr_outin() version of this fn that also allows
624 * clocking data back in. Patches gladly accepted!
626 extern void jtag_add_dr_out(jtag_tap_t* tap,
627 int num_fields, const int* num_bits, const u32* value,
628 tap_state_t end_state);
632 * jtag_add_statemove() moves from the current state to @a goal_state.
634 * This function was originally designed to handle the XSTATE command
635 * from the XSVF specification.
637 * @param goal_state The final TAP state.
638 * @return ERROR_OK on success, or an error code on failure.
640 extern int jtag_add_statemove(tap_state_t goal_state);