shuffled comments about for jtag_add_dr_out() fn.
[openocd.git] / src / jtag / jtag.h
blobccd17ffea93195ad2cf009752d84950aebb8c7bc
1 /***************************************************************************
2 * Copyright (C) 2005 by Dominic Rath *
3 * Dominic.Rath@gmx.de *
4 * *
5 * Copyright (C) 2007,2008 Øyvind Harboe *
6 * oyvind.harboe@zylin.com *
7 * *
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. *
12 * *
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. *
17 * *
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 ***************************************************************************/
23 #ifndef JTAG_H
24 #define JTAG_H
26 #include "binarybuffer.h"
27 #include "log.h"
30 #ifdef _DEBUG_JTAG_IO_
31 #define DEBUG_JTAG_IO(expr ...) LOG_DEBUG(expr)
32 #else
33 #define DEBUG_JTAG_IO(expr ...)
34 #endif
36 #ifndef DEBUG_JTAG_IOZ
37 #define DEBUG_JTAG_IOZ 64
38 #endif
40 /*-----<Macros>--------------------------------------------------*/
42 /** When given an array, compute its DIMension, i.e. number of elements in the array */
43 #define DIM(x) (sizeof(x)/sizeof((x)[0]))
45 /** Calculate the number of bytes required to hold @a n TAP scan bits */
46 #define TAP_SCAN_BYTES(n) CEIL(n, 8)
48 /*-----</Macros>-------------------------------------------------*/
53 * Tap states from ARM7TDMI-S Technical reference manual.
54 * Also, validated against several other ARM core technical manuals.
56 * N.B. tap_get_tms_path() was changed to reflect this corrected
57 * numbering and ordering of the TAP states.
59 * DANGER!!!! some interfaces care about the actual numbers used
60 * as they are handed off directly to hardware implementations.
63 typedef enum tap_state
65 #if BUILD_ECOSBOARD
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,
74 #else
75 /* Proper ARM recommended numbers */
76 TAP_DREXIT2 = 0x0,
77 TAP_DREXIT1 = 0x1,
78 TAP_DRSHIFT = 0x2,
79 TAP_DRPAUSE = 0x3,
80 TAP_IRSELECT = 0x4,
81 TAP_DRUPDATE = 0x5,
82 TAP_DRCAPTURE = 0x6,
83 TAP_DRSELECT = 0x7,
84 TAP_IREXIT2 = 0x8,
85 TAP_IREXIT1 = 0x9,
86 TAP_IRSHIFT = 0xa,
87 TAP_IRPAUSE = 0xb,
88 TAP_IDLE = 0xc,
89 TAP_IRUPDATE = 0xd,
90 TAP_IRCAPTURE = 0xe,
91 TAP_RESET = 0x0f,
93 TAP_NUM_STATES = 0x10,
95 TAP_INVALID = -1,
96 #endif
97 } tap_state_t;
99 typedef struct tap_transition_s
101 tap_state_t high;
102 tap_state_t low;
103 } tap_transition_t;
105 //extern tap_transition_t tap_transitions[16]; /* describe the TAP state diagram */
108 /*-----<Cable Helper API>-------------------------------------------*/
110 /* The "Cable Helper API" is what the cable drivers can use to help implement
111 * their "Cable API". So a Cable Helper API is a set of helper functions used by
112 * cable drivers, and this is different from a Cable API. A "Cable API" is what
113 * higher level code used to talk to a cable.
117 /** implementation of wrapper function tap_set_state() */
118 void tap_set_state_impl(tap_state_t new_state);
121 * Function tap_set_state
122 * sets the state of a "state follower" which tracks the state of the TAPs connected to the
123 * cable. The state follower is hopefully always in the same state as the actual
124 * TAPs in the jtag chain, and will be so if there are no bugs in the tracking logic within that
125 * cable driver. All the cable drivers call this function to indicate the state they think
126 * the TAPs attached to their cables are in. Because this function can also log transitions,
127 * it will be helpful to call this function with every transition that the TAPs being manipulated
128 * are expected to traverse, not just end points of a multi-step state path.
129 * @param new_state is the state we think the TAPs are currently in or are about to enter.
131 #if defined(_DEBUG_JTAG_IO_)
132 #define tap_set_state(new_state) \
133 do { \
134 LOG_DEBUG( "tap_set_state(%s)", tap_state_name(new_state) ); \
135 tap_set_state_impl(new_state); \
136 } while (0)
137 #else
138 static inline void tap_set_state(tap_state_t new_state)
140 tap_set_state_impl(new_state);
143 #endif
146 * Function tap_get_state
147 * gets the state of the "state follower" which tracks the state of the TAPs connected to
148 * the cable.
149 * @see tap_set_state
150 * @return tap_state_t - The state the TAPs are in now.
152 tap_state_t tap_get_state(void);
155 * Function tap_set_end_state
156 * sets the state of an "end state follower" which tracks the state that any cable driver
157 * thinks will be the end (resultant) state of the current TAP SIR or SDR operation. At completion
158 * of that TAP operation this value is copied into the state follower via tap_set_state().
159 * @param new_end_state is that state the TAPs should enter at completion of a pending TAP operation.
161 void tap_set_end_state(tap_state_t new_end_state);
164 * Function tap_get_end_state
165 * @see tap_set_end_state
166 * @return tap_state_t - The state the TAPs should be in at completion of the current TAP operation.
168 tap_state_t tap_get_end_state(void);
171 * Function tap_get_tms_path
172 * returns a 7 bit long "bit sequence" indicating what has to be done with TMS
173 * during a sequence of seven TAP clock cycles in order to get from
174 * state \a "from" to state \a "to".
175 * @param from is the starting state
176 * @param to is the resultant or final state
177 * @return int - a 7 bit sequence, with the first bit in the sequence at bit 0.
179 int tap_get_tms_path(tap_state_t from, tap_state_t to);
183 * Function int tap_get_tms_path_len
184 * returns the total number of bits that represents a TMS path
185 * transition as given by the function tap_get_tms_path().
187 * For at least one interface (JLink) it's not OK to simply "pad" TMS sequences
188 * to fit a whole byte. (I suspect this is a general TAP problem within OOCD.)
189 * Padding TMS causes all manner of instability that's not easily
190 * discovered. Using this routine we can apply EXACTLY the state transitions
191 * required to make something work - no more - no less.
193 * @param from is the starting state
194 * @param to is the resultant or final state
195 * @return int - the total number of bits in a transition.
197 int tap_get_tms_path_len(tap_state_t from, tap_state_t to);
201 * Function tap_move_ndx
202 * when given a stable state, returns an index from 0-5. The index corresponds to a
203 * sequence of stable states which are given in this order: <p>
204 * { TAP_RESET, TAP_IDLE, TAP_DRSHIFT, TAP_DRPAUSE, TAP_IRSHIFT, TAP_IRPAUSE }
205 * <p>
206 * This sequence corresponds to look up tables which are used in some of the
207 * cable drivers.
208 * @param astate is the stable state to find in the sequence. If a non stable
209 * state is passed, this may cause the program to output an error message
210 * and terminate.
211 * @return int - the array (or sequence) index as described above
213 int tap_move_ndx(tap_state_t astate);
216 * Function tap_is_state_stable
217 * returns true if the \a astate is stable.
219 bool tap_is_state_stable(tap_state_t astate);
222 * Function tap_state_transition
223 * takes a current TAP state and returns the next state according to the tms value.
224 * @param current_state is the state of a TAP currently.
225 * @param tms is either zero or non-zero, just like a real TMS line in a jtag interface.
226 * @return tap_state_t - the next state a TAP would enter.
228 tap_state_t tap_state_transition(tap_state_t current_state, bool tms);
231 * Function tap_state_name
232 * Returns a string suitable for display representing the JTAG tap_state
234 const char* tap_state_name(tap_state_t state);
236 #ifdef _DEBUG_JTAG_IO_
238 * @brief Prints verbose TAP state transitions for the given TMS/TDI buffers.
239 * @param tms_buf must points to a buffer containing the TMS bitstream.
240 * @param tdi_buf must points to a buffer containing the TDI bitstream.
241 * @param tap_len must specify the length of the TMS/TDI bitstreams.
242 * @param start_tap_state must specify the current TAP state.
243 * @returns the final TAP state; pass as @a start_tap_state in following call.
245 tap_state_t jtag_debug_state_machine(const void *tms_buf, const void *tdi_buf,
246 unsigned tap_len, tap_state_t start_tap_state);
247 #else
248 static inline tap_state_t jtag_debug_state_machine(const void *tms_buf,
249 const void *tdi_buf, unsigned tap_len, tap_state_t start_tap_state)
251 return start_tap_state;
253 #endif // _DEBUG_JTAG_IO_
255 /*-----</Cable Helper API>------------------------------------------*/
258 extern tap_state_t cmd_queue_end_state; /* finish DR scans in dr_end_state */
259 extern tap_state_t cmd_queue_cur_state; /* current TAP state */
261 typedef void* error_handler_t; /* Later on we can delete error_handler_t, but keep it for now to make patches more readable */
263 struct scan_field_s;
264 typedef int (*in_handler_t)(u8* in_value, void* priv, struct scan_field_s* field);
266 typedef struct scan_field_s
268 jtag_tap_t* tap; /* tap pointer this instruction refers to */
269 int num_bits; /* number of bits this field specifies (up to 32) */
270 u8* out_value; /* value to be scanned into the device */
271 u8* in_value; /* pointer to a 32-bit memory location to take data scanned out */
273 u8* check_value; /* Used together with jtag_add_dr_scan_check() to check data clocked
274 in */
275 u8* check_mask; /* mask to go with check_value */
277 /* internal work space */
278 int allocated; /* in_value has been allocated for the queue */
279 int modified; /* did we modify the in_value? */
280 u8 intmp[4]; /* temporary storage for checking synchronously */
281 } scan_field_t;
283 enum scan_type {
284 /* IN: from device to host, OUT: from host to device */
285 SCAN_IN = 1, SCAN_OUT = 2, SCAN_IO = 3
288 typedef struct scan_command_s
290 int ir_scan; /* instruction/not data scan */
291 int num_fields; /* number of fields in *fields array */
292 scan_field_t* fields; /* pointer to an array of data scan fields */
293 tap_state_t end_state; /* TAP state in which JTAG commands should finish */
294 } scan_command_t;
296 typedef struct statemove_command_s
298 tap_state_t end_state; /* TAP state in which JTAG commands should finish */
299 } statemove_command_t;
301 typedef struct pathmove_command_s
303 int num_states; /* number of states in *path */
304 tap_state_t* path; /* states that have to be passed */
305 } pathmove_command_t;
307 typedef struct runtest_command_s
309 int num_cycles; /* number of cycles that should be spent in Run-Test/Idle */
310 tap_state_t end_state; /* TAP state in which JTAG commands should finish */
311 } runtest_command_t;
314 typedef struct stableclocks_command_s
316 int num_cycles; /* number of clock cycles that should be sent */
317 } stableclocks_command_t;
320 typedef struct reset_command_s
322 int trst; /* trst/srst 0: deassert, 1: assert, -1: don't change */
323 int srst;
324 } reset_command_t;
326 typedef struct end_state_command_s
328 tap_state_t end_state; /* TAP state in which JTAG commands should finish */
329 } end_state_command_t;
331 typedef struct sleep_command_s
333 u32 us; /* number of microseconds to sleep */
334 } sleep_command_t;
336 typedef union jtag_command_container_u
338 scan_command_t* scan;
339 statemove_command_t* statemove;
340 pathmove_command_t* pathmove;
341 runtest_command_t* runtest;
342 stableclocks_command_t* stableclocks;
343 reset_command_t* reset;
344 end_state_command_t* end_state;
345 sleep_command_t* sleep;
346 } jtag_command_container_t;
348 enum jtag_command_type {
349 JTAG_SCAN = 1,
350 JTAG_STATEMOVE = 2,
351 JTAG_RUNTEST = 3,
352 JTAG_RESET = 4,
353 JTAG_END_STATE = 5,
354 JTAG_PATHMOVE = 6,
355 JTAG_SLEEP = 7,
356 JTAG_STABLECLOCKS = 8
359 typedef struct jtag_command_s
361 jtag_command_container_t cmd;
362 enum jtag_command_type type;
363 struct jtag_command_s* next;
364 } jtag_command_t;
366 extern jtag_command_t* jtag_command_queue;
368 /* forward declaration */
369 typedef struct jtag_tap_event_action_s jtag_tap_event_action_t;
371 /* this is really: typedef jtag_tap_t */
372 /* But - the typedef is done in "types.h" */
373 /* due to "forward decloration reasons" */
374 struct jtag_tap_s
376 const char* chip;
377 const char* tapname;
378 const char* dotted_name;
379 int abs_chain_position;
380 int enabled;
381 int ir_length; /* size of instruction register */
382 u32 ir_capture_value;
383 u8* expected; /* Capture-IR expected value */
384 u32 ir_capture_mask;
385 u8* expected_mask; /* Capture-IR expected mask */
386 u32 idcode; /* device identification code */
387 u32* expected_ids; /* Array of expected identification codes */
388 u8 expected_ids_cnt; /* Number of expected identification codes */
389 u8* cur_instr; /* current instruction */
390 int bypass; /* bypass register selected */
392 jtag_tap_event_action_t* event_action;
394 jtag_tap_t* next_tap;
396 extern jtag_tap_t* jtag_AllTaps(void);
397 extern jtag_tap_t* jtag_TapByPosition(int n);
398 extern jtag_tap_t* jtag_TapByString(const char* dotted_name);
399 extern jtag_tap_t* jtag_TapByJimObj(Jim_Interp* interp, Jim_Obj* obj);
400 extern jtag_tap_t* jtag_TapByAbsPosition(int abs_position);
401 extern int jtag_NumEnabledTaps(void);
402 extern int jtag_NumTotalTaps(void);
404 static __inline__ jtag_tap_t* jtag_NextEnabledTap(jtag_tap_t* p)
406 if (p == NULL)
408 /* start at the head of list */
409 p = jtag_AllTaps();
411 else
413 /* start *after* this one */
414 p = p->next_tap;
416 while (p)
418 if (p->enabled)
420 break;
422 else
424 p = p->next_tap;
428 return p;
432 enum reset_line_mode {
433 LINE_OPEN_DRAIN = 0x0,
434 LINE_PUSH_PULL = 0x1,
437 typedef struct jtag_interface_s
439 char* name;
441 /* queued command execution
443 int (*execute_queue)(void);
445 /* interface initalization
447 int (*speed)(int speed);
448 int (*register_commands)(struct command_context_s* cmd_ctx);
449 int (*init)(void);
450 int (*quit)(void);
452 /* returns JTAG maxium speed for KHz. 0=RTCK. The function returns
453 * a failure if it can't support the KHz/RTCK.
455 * WARNING!!!! if RTCK is *slow* then think carefully about
456 * whether you actually want to support this in the driver.
457 * Many target scripts are written to handle the absence of RTCK
458 * and use a fallback kHz TCK.
460 int (*khz)(int khz, int* jtag_speed);
462 /* returns the KHz for the provided JTAG speed. 0=RTCK. The function returns
463 * a failure if it can't support the KHz/RTCK. */
464 int (*speed_div)(int speed, int* khz);
466 /* Read and clear the power dropout flag. Note that a power dropout
467 * can be transitionary, easily much less than a ms.
469 * So to find out if the power is *currently* on, you must invoke
470 * this method twice. Once to clear the power dropout flag and a
471 * second time to read the current state.
473 * Currently the default implementation is never to detect power dropout.
475 int (*power_dropout)(int* power_dropout);
477 /* Read and clear the srst asserted detection flag.
479 * NB!!!! like power_dropout this does *not* read the current
480 * state. srst assertion is transitionary and *can* be much
481 * less than 1ms.
483 int (*srst_asserted)(int* srst_asserted);
484 } jtag_interface_t;
486 enum jtag_event {
487 JTAG_TRST_ASSERTED
490 extern char* jtag_event_strings[];
492 enum jtag_tap_event {
493 JTAG_TAP_EVENT_ENABLE,
494 JTAG_TAP_EVENT_DISABLE
497 extern const Jim_Nvp nvp_jtag_tap_event[];
499 struct jtag_tap_event_action_s
501 enum jtag_tap_event event;
502 Jim_Obj* body;
503 jtag_tap_event_action_t* next;
506 extern int jtag_trst;
507 extern int jtag_srst;
509 typedef struct jtag_event_callback_s
511 int (*callback)(enum jtag_event event, void* priv);
512 void* priv;
513 struct jtag_event_callback_s* next;
514 } jtag_event_callback_t;
516 extern jtag_event_callback_t* jtag_event_callbacks;
518 extern jtag_interface_t* jtag; /* global pointer to configured JTAG interface */
520 extern int jtag_speed;
521 extern int jtag_speed_post_reset;
523 enum reset_types {
524 RESET_NONE = 0x0,
525 RESET_HAS_TRST = 0x1,
526 RESET_HAS_SRST = 0x2,
527 RESET_TRST_AND_SRST = 0x3,
528 RESET_SRST_PULLS_TRST = 0x4,
529 RESET_TRST_PULLS_SRST = 0x8,
530 RESET_TRST_OPEN_DRAIN = 0x10,
531 RESET_SRST_PUSH_PULL = 0x20,
534 extern enum reset_types jtag_reset_config;
536 /* initialize interface upon startup. A successful no-op
537 * upon subsequent invocations
539 extern int jtag_interface_init(struct command_context_s* cmd_ctx);
541 /* initialize JTAG chain using only a RESET reset. If init fails,
542 * try reset + init.
544 extern int jtag_init(struct command_context_s* cmd_ctx);
546 /* reset, then initialize JTAG chain */
547 extern int jtag_init_reset(struct command_context_s* cmd_ctx);
548 extern int jtag_register_commands(struct command_context_s* cmd_ctx);
550 /* JTAG interface, can be implemented with a software or hardware fifo
552 * TAP_DRSHIFT and TAP_IRSHIFT are illegal end states. TAP_DRSHIFT/IRSHIFT as end states
553 * can be emulated by using a larger scan.
555 * Code that is relatively insensitive to the path(as long
556 * as it is JTAG compliant) taken through state machine can use
557 * endstate for jtag_add_xxx_scan(). Otherwise the pause state must be
558 * specified as end state and a subsequent jtag_add_pathmove() must
559 * be issued.
562 extern void jtag_add_ir_scan(int num_fields, scan_field_t* fields, tap_state_t endstate);
563 /* same as jtag_add_ir_scan except no verify is performed */
564 extern void jtag_add_ir_scan_noverify(int num_fields, scan_field_t *fields, tap_state_t state);
565 extern int interface_jtag_add_ir_scan(int num_fields, scan_field_t* fields, tap_state_t endstate);
566 extern void jtag_add_dr_scan(int num_fields, scan_field_t* fields, tap_state_t endstate);
568 /* set in_value to point to 32 bits of memory to scan into. This function
569 * is a way to handle the case of synchronous and asynchronous
570 * JTAG queues.
572 * In the event of an asynchronous queue execution the queue buffer
573 * allocation method is used, for the synchronous case the temporary 32 bits come
574 * from the input field itself.
577 #ifndef HAVE_JTAG_MINIDRIVER_H
578 extern void jtag_alloc_in_value32(scan_field_t *field);
579 #else
580 static __inline__ void jtag_alloc_in_value32(scan_field_t *field)
582 field->in_value=field->intmp;
584 #endif
588 /* This version of jtag_add_dr_scan() uses the check_value/mask fields */
589 extern void jtag_add_dr_scan_check(int num_fields, scan_field_t* fields, tap_state_t endstate);
590 extern int interface_jtag_add_dr_scan(int num_fields, scan_field_t* fields, tap_state_t endstate);
591 extern void jtag_add_plain_ir_scan(int num_fields, scan_field_t* fields, tap_state_t endstate);
592 extern int interface_jtag_add_plain_ir_scan(int num_fields, scan_field_t* fields, tap_state_t endstate);
593 extern void jtag_add_plain_dr_scan(int num_fields, scan_field_t* fields, tap_state_t endstate);
594 extern int interface_jtag_add_plain_dr_scan(int num_fields, scan_field_t* fields, tap_state_t endstate);
597 /* Simplest/typical callback - do some conversion on the data clocked in.
598 * This callback is for such conversion that can not fail.
599 * For conversion types or checks that can
600 * fail, use the jtag_callback_t variant */
601 typedef void (*jtag_callback1_t)(u8 *in);
603 #ifndef HAVE_JTAG_MINIDRIVER_H
604 /* A simpler version of jtag_add_callback4 */
605 extern void jtag_add_callback(jtag_callback1_t, u8 *in);
606 #else
607 /* implemented by minidriver */
608 #endif
611 /* This type can store an integer safely by a normal cast on 64 and
612 * 32 bit systems. */
613 typedef intptr_t jtag_callback_data_t;
615 /* The generic callback mechanism.
617 * The callback is invoked with three arguments. The first argument is
618 * the pointer to the data clocked in.
620 typedef int (*jtag_callback_t)(u8 *in, jtag_callback_data_t data1, jtag_callback_data_t data2, jtag_callback_data_t data3);
623 /* This callback can be executed immediately the queue has been flushed. Note that
624 * the JTAG queue can either be executed synchronously or asynchronously. Typically
625 * for USB the queue is executed asynchronously. For low latency interfaces, the
626 * queue may be executed synchronously.
628 * These callbacks are typically executed *after* the *entire* JTAG queue has been
629 * executed for e.g. USB interfaces.
631 * The callbacks are guaranteeed to be invoked in the order that they were queued.
633 * The strange name is due to C's lack of overloading using function arguments
635 * The callback mechansim is very general and does not really make any assumptions
636 * about what the callback does and what the arguments are.
638 * in - typically used to point to the data to operate on. More often than not
639 * this will be the data clocked in during a shift operation
641 * data1 - an integer that is big enough to be used either as an 'int' or
642 * cast to/from a pointer
644 * data2 - an integer that is big enough to be used either as an 'int' or
645 * cast to/from a pointer
647 * Why stop at 'data2' for arguments? Somewhat historical reasons. This is
648 * sufficient to implement the jtag_check_value_mask(), besides the
649 * line is best drawn somewhere...
651 * If the execution of the queue fails before the callbacks, then the
652 * callbacks may or may not be invoked depending on driver implementation.
654 #ifndef HAVE_JTAG_MINIDRIVER_H
655 extern void jtag_add_callback4(jtag_callback_t, u8 *in, jtag_callback_data_t data1, jtag_callback_data_t data2, jtag_callback_data_t data3);
656 #else
657 /* implemented by minidriver */
658 #endif
661 /* run a TAP_RESET reset. End state is TAP_RESET, regardless
662 * of start state.
664 extern void jtag_add_tlr(void);
665 extern int interface_jtag_add_tlr(void);
667 /* Application code *must* assume that interfaces will
668 * implement transitions between states with different
669 * paths and path lengths through the state diagram. The
670 * path will vary across interface and also across versions
671 * of the same interface over time. Even if the OpenOCD code
672 * is unchanged, the actual path taken may vary over time
673 * and versions of interface firmware or PCB revisions.
675 * Use jtag_add_pathmove() when specific transition sequences
676 * are required.
678 * Do not use jtag_add_pathmove() unless you need to, but do use it
679 * if you have to.
681 * DANGER! If the target is dependent upon a particular sequence
682 * of transitions for things to work correctly(e.g. as a workaround
683 * for an errata that contradicts the JTAG standard), then pathmove
684 * must be used, even if some jtag interfaces happen to use the
685 * desired path. Worse, the jtag interface used for testing a
686 * particular implementation, could happen to use the "desired"
687 * path when transitioning to/from end
688 * state.
690 * A list of unambigious single clock state transitions, not
691 * all drivers can support this, but it is required for e.g.
692 * XScale and Xilinx support
694 * Note! TAP_RESET must not be used in the path!
696 * Note that the first on the list must be reachable
697 * via a single transition from the current state.
699 * All drivers are required to implement jtag_add_pathmove().
700 * However, if the pathmove sequence can not be precisely
701 * executed, an interface_jtag_add_pathmove() or jtag_execute_queue()
702 * must return an error. It is legal, but not recommended, that
703 * a driver returns an error in all cases for a pathmove if it
704 * can only implement a few transitions and therefore
705 * a partial implementation of pathmove would have little practical
706 * application.
708 extern void jtag_add_pathmove(int num_states, tap_state_t* path);
709 extern int interface_jtag_add_pathmove(int num_states, tap_state_t* path);
711 /* go to TAP_IDLE, if we're not already there and cycle
712 * precisely num_cycles in the TAP_IDLE after which move
713 * to the end state, if it is != TAP_IDLE
715 * nb! num_cycles can be 0, in which case the fn will navigate
716 * to endstate via TAP_IDLE
718 extern void jtag_add_runtest(int num_cycles, tap_state_t endstate);
719 extern int interface_jtag_add_runtest(int num_cycles, tap_state_t endstate);
721 /* A reset of the TAP state machine can be requested.
723 * Whether tms or trst reset is used depends on the capabilities of
724 * the target and jtag interface(reset_config command configures this).
726 * srst can driver a reset of the TAP state machine and vice
727 * versa
729 * Application code may need to examine value of jtag_reset_config
730 * to determine the proper codepath
732 * DANGER! Even though srst drives trst, trst might not be connected to
733 * the interface, and it might actually be *harmful* to assert trst in this case.
735 * This is why combinations such as "reset_config srst_only srst_pulls_trst"
736 * are supported.
738 * only req_tlr_or_trst and srst can have a transition for a
739 * call as the effects of transitioning both at the "same time"
740 * are undefined, but when srst_pulls_trst or vice versa,
741 * then trst & srst *must* be asserted together.
743 extern void jtag_add_reset(int req_tlr_or_trst, int srst);
745 /* this drives the actual srst and trst pins. srst will always be 0
746 * if jtag_reset_config & RESET_SRST_PULLS_TRST != 0 and ditto for
747 * trst.
749 * the higher level jtag_add_reset will invoke jtag_add_tlr() if
750 * approperiate
752 extern int interface_jtag_add_reset(int trst, int srst);
753 extern void jtag_add_end_state(tap_state_t endstate);
754 extern int interface_jtag_add_end_state(tap_state_t endstate);
755 extern void jtag_add_sleep(u32 us);
756 extern int interface_jtag_add_sleep(u32 us);
760 * Function jtag_add_stable_clocks
761 * first checks that the state in which the clocks are to be issued is
762 * stable, then queues up clock_count clocks for transmission.
764 void jtag_add_clocks(int num_cycles);
765 int interface_jtag_add_clocks(int num_cycles);
769 * For software FIFO implementations, the queued commands can be executed
770 * during this call or earlier. A sw queue might decide to push out
771 * some of the jtag_add_xxx() operations once the queue is "big enough".
773 * This fn will return an error code if any of the prior jtag_add_xxx()
774 * calls caused a failure, e.g. check failure. Note that it does not
775 * matter if the operation was executed *before* jtag_execute_queue(),
776 * jtag_execute_queue() will still return an error code.
778 * All jtag_add_xxx() calls that have in_handler!=NULL will have been
779 * executed when this fn returns, but if what has been queued only
780 * clocks data out, without reading anything back, then JTAG could
781 * be running *after* jtag_execute_queue() returns. The API does
782 * not define a way to flush a hw FIFO that runs *after*
783 * jtag_execute_queue() returns.
785 * jtag_add_xxx() commands can either be executed immediately or
786 * at some time between the jtag_add_xxx() fn call and jtag_execute_queue().
788 extern int jtag_execute_queue(void);
790 /* same as jtag_execute_queue() but does not clear the error flag */
791 extern void jtag_execute_queue_noclear(void);
793 /* this flag is set when an error occurs while executing the queue. cleared
794 * by jtag_execute_queue()
796 * this flag can also be set from application code if some error happens
797 * during processing that should be reported during jtag_execute_queue().
799 extern int jtag_error;
801 static __inline__ void jtag_set_error(int error)
803 if ((error==ERROR_OK)||(jtag_error!=ERROR_OK))
805 /* keep first error */
806 return;
808 jtag_error=error;
813 /* can be implemented by hw+sw */
814 extern int interface_jtag_execute_queue(void);
815 extern int jtag_power_dropout(int* dropout);
816 extern int jtag_srst_asserted(int* srst_asserted);
818 /* JTAG support functions */
819 struct invalidstruct
824 /* execute jtag queue and check value and use mask if mask is != NULL. invokes
825 * jtag_set_error() with any error. */
826 extern void jtag_check_value_mask(scan_field_t *field, u8 *value, u8 *mask);
827 extern enum scan_type jtag_scan_type(scan_command_t* cmd);
828 extern int jtag_scan_size(scan_command_t* cmd);
829 extern int jtag_read_buffer(u8* buffer, scan_command_t* cmd);
830 extern int jtag_build_buffer(scan_command_t* cmd, u8** buffer);
832 extern void jtag_sleep(u32 us);
833 extern int jtag_call_event_callbacks(enum jtag_event event);
834 extern int jtag_register_event_callback(int (* callback)(enum jtag_event event, void* priv), void* priv);
836 extern int jtag_verify_capture_ir;
838 void jtag_tap_handle_event(jtag_tap_t* tap, enum jtag_tap_event e);
840 /* error codes
841 * JTAG subsystem uses codes between -100 and -199 */
843 #define ERROR_JTAG_INIT_FAILED (-100)
844 #define ERROR_JTAG_INVALID_INTERFACE (-101)
845 #define ERROR_JTAG_NOT_IMPLEMENTED (-102)
846 #define ERROR_JTAG_TRST_ASSERTED (-103)
847 #define ERROR_JTAG_QUEUE_FAILED (-104)
848 #define ERROR_JTAG_NOT_STABLE_STATE (-105)
849 #define ERROR_JTAG_DEVICE_ERROR (-107)
852 /* this allows JTAG devices to implement the entire jtag_xxx() layer in hw/sw */
853 #ifdef HAVE_JTAG_MINIDRIVER_H
854 /* Here a #define MINIDRIVER() and an inline version of hw fifo interface_jtag_add_dr_out can be defined */
855 #include "jtag_minidriver.h"
856 #define MINIDRIVER(a) notused ## a
857 #else
858 #define MINIDRIVER(a) a
859 extern void interface_jtag_add_dr_out(jtag_tap_t* tap, int num_fields, const int* num_bits, const u32* value,
860 tap_state_t end_state);
862 #endif
864 /* jtag_add_dr_out() is a version of jtag_add_dr_scan() which
865 * only scans data out. It operates on 32 bit integers instead
866 * of 8 bit, which makes it a better impedance match with
867 * the calling code which often operate on 32 bit integers.
869 * Current or end_state can not be TAP_RESET. end_state can be TAP_INVALID
871 * num_bits[i] is the number of bits to clock out from value[i] LSB first.
873 * If the device is in bypass, then that is an error condition in
874 * the caller code that is not detected by this fn, whereas jtag_add_dr_scan()
875 * does detect it. Similarly if the device is not in bypass, data must
876 * be passed to it.
878 * If anything fails, then jtag_error will be set and jtag_execute() will
879 * return an error. There is no way to determine if there was a failure
880 * during this function call.
882 * This is an inline fn to speed up embedded hosts. Also note that
883 * interface_jtag_add_dr_out() can be a *small* inline function for
884 * embedded hosts.
886 * There is no jtag_add_dr_outin() version of this fn that also allows
887 * clocking data back in. Patches gladly accepted!
889 static __inline__ void jtag_add_dr_out(jtag_tap_t* tap, int num_fields, const int* num_bits, const u32* value,
890 tap_state_t end_state)
892 if (end_state != TAP_INVALID)
893 cmd_queue_end_state = end_state;
894 cmd_queue_cur_state = cmd_queue_end_state;
895 interface_jtag_add_dr_out(tap, num_fields, num_bits, value, cmd_queue_end_state);
899 #endif /* JTAG_H */