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 ***************************************************************************/
27 #include "binarybuffer.h"
33 #ifdef _DEBUG_JTAG_IO_
34 #define DEBUG_JTAG_IO(expr ...) LOG_DEBUG(expr)
36 #define DEBUG_JTAG_IO(expr ...)
39 #ifndef DEBUG_JTAG_IOZ
40 #define DEBUG_JTAG_IOZ 64
44 /* 16 Tap States, from page 21 of ASSET InterTech, Inc.'s svf.pdf
47 TAP_RESET = 0, TAP_IDLE = 8,
48 TAP_DRSELECT = 1, TAP_DRCAPTURE = 2, TAP_DRSHIFT = 3, TAP_DREXIT1 = 4,
49 TAP_DRPAUSE = 5, TAP_DREXIT2 = 6, TAP_DRUPDATE = 7,
50 TAP_IRSELECT = 9, TAP_IRCAPTURE = 10, TAP_IRSHIFT = 11, TAP_IREXIT1 = 12,
51 TAP_IRPAUSE = 13, TAP_IREXIT2 = 14, TAP_IRUPDATE = 15,
53 TAP_NUM_STATES = 16, TAP_INVALID = -1,
56 typedef enum tap_state tap_state_t;
58 typedef struct tap_transition_s
64 //extern tap_transition_t tap_transitions[16]; /* describe the TAP state diagram */
67 /*-----<Cable Helper API>-------------------------------------------*/
69 /* The "Cable Helper API" is what the cable drivers can use to help implement
70 * their "Cable API". So a Cable Helper API is a set of helper functions used by
71 * cable drivers, and this is different from a Cable API. A "Cable API" is what
72 * higher level code used to talk to a cable.
76 /** implementation of wrapper function tap_set_state() */
77 void tap_set_state_impl(tap_state_t new_state);
80 * Function tap_set_state
81 * sets the state of a "state follower" which tracks the state of the TAPs connected to the
82 * cable. The state follower is hopefully always in the same state as the actual
83 * TAPs in the jtag chain, and will be so if there are no bugs in the tracking logic within that
84 * cable driver. All the cable drivers call this function to indicate the state they think
85 * the TAPs attached to their cables are in. Because this function can also log transitions,
86 * it will be helpful to call this function with every transition that the TAPs being manipulated
87 * are expected to traverse, not just end points of a multi-step state path.
88 * @param new_state is the state we think the TAPs are currently in or are about to enter.
90 #if defined(_DEBUG_JTAG_IO_)
91 #define tap_set_state(new_state) \
93 LOG_DEBUG( "tap_set_state(%s)", tap_state_name(new_state) ); \
94 tap_set_state_impl(new_state); \
97 static inline void tap_set_state(tap_state_t new_state)
99 tap_set_state_impl(new_state);
105 * Function tap_get_state
106 * gets the state of the "state follower" which tracks the state of the TAPs connected to
109 * @return tap_state_t - The state the TAPs are in now.
111 tap_state_t tap_get_state(void);
114 * Function tap_set_end_state
115 * sets the state of an "end state follower" which tracks the state that any cable driver
116 * thinks will be the end (resultant) state of the current TAP SIR or SDR operation. At completion
117 * of that TAP operation this value is copied into the state follower via tap_set_state().
118 * @param new_end_state is that state the TAPs should enter at completion of a pending TAP operation.
120 void tap_set_end_state(tap_state_t new_end_state);
123 * Function tap_get_end_state
124 * @see tap_set_end_state
125 * @return tap_state_t - The state the TAPs should be in at completion of the current TAP operation.
127 tap_state_t tap_get_end_state(void);
130 * Function tap_get_tms_path
131 * returns a 7 bit long "bit sequence" indicating what has to be done with TMS
132 * during a sequence of seven TAP clock cycles in order to get from
133 * state \a "from" to state \a "to".
134 * @param from is the starting state
135 * @param to is the resultant or final state
136 * @return int - a 7 bit sequence, with the first bit in the sequence at bit 0.
138 int tap_get_tms_path(tap_state_t from, tap_state_t to);
141 * Function tap_move_ndx
142 * when given a stable state, returns an index from 0-5. The index corresponds to a
143 * sequence of stable states which are given in this order: <p>
144 * { TAP_RESET, TAP_IDLE, TAP_DRSHIFT, TAP_DRPAUSE, TAP_IRSHIFT, TAP_IRPAUSE }
146 * This sequence corresponds to look up tables which are used in some of the
148 * @param astate is the stable state to find in the sequence. If a non stable
149 * state is passed, this may cause the program to output an error message
151 * @return int - the array (or sequence) index as described above
153 int tap_move_ndx(tap_state_t astate);
156 * Function tap_is_state_stable
157 * returns true if the \a astate is stable.
159 bool tap_is_state_stable(tap_state_t astate);
162 * Function tap_state_transition
163 * takes a current TAP state and returns the next state according to the tms value.
164 * @param current_state is the state of a TAP currently.
165 * @param tms is either zero or non-zero, just like a real TMS line in a jtag interface.
166 * @return tap_state_t - the next state a TAP would enter.
168 tap_state_t tap_state_transition(tap_state_t current_state, bool tms);
171 * Function tap_state_name
172 * Returns a string suitable for display representing the JTAG tap_state
174 const char* tap_state_name(tap_state_t state);
176 /*-----</Cable Helper API>------------------------------------------*/
179 extern tap_state_t cmd_queue_end_state; /* finish DR scans in dr_end_state */
180 extern tap_state_t cmd_queue_cur_state; /* current TAP state */
182 typedef void* error_handler_t; /* Later on we can delete error_handler_t, but keep it for now to make patches more readable */
185 typedef int (*in_handler_t)(u8* in_value, void* priv, struct scan_field_s* field);
187 typedef struct scan_field_s
189 jtag_tap_t* tap; /* tap pointer this instruction refers to */
190 int num_bits; /* number of bits this field specifies (up to 32) */
191 u8* out_value; /* value to be scanned into the device */
192 u8* out_mask; /* only masked bits care */
193 u8* in_value; /* pointer to a 32-bit memory location to take data scanned out */
194 /* in_check_value/mask, in_handler_error_handler, in_handler_priv can be used by the in handler, otherwise they contain garbage */
195 u8* in_check_value; /* used to validate scan results */
196 u8* in_check_mask; /* check specified bits against check_value */
197 in_handler_t in_handler; /* process received buffer using this handler */
198 void* in_handler_priv; /* additional information for the in_handler */
202 /* IN: from device to host, OUT: from host to device */
203 SCAN_IN = 1, SCAN_OUT = 2, SCAN_IO = 3
206 typedef struct scan_command_s
208 int ir_scan; /* instruction/not data scan */
209 int num_fields; /* number of fields in *fields array */
210 scan_field_t* fields; /* pointer to an array of data scan fields */
211 tap_state_t end_state; /* TAP state in which JTAG commands should finish */
214 typedef struct statemove_command_s
216 tap_state_t end_state; /* TAP state in which JTAG commands should finish */
217 } statemove_command_t;
219 typedef struct pathmove_command_s
221 int num_states; /* number of states in *path */
222 tap_state_t* path; /* states that have to be passed */
223 } pathmove_command_t;
225 typedef struct runtest_command_s
227 int num_cycles; /* number of cycles that should be spent in Run-Test/Idle */
228 tap_state_t end_state; /* TAP state in which JTAG commands should finish */
232 typedef struct stableclocks_command_s
234 int num_cycles; /* number of clock cycles that should be sent */
235 } stableclocks_command_t;
238 typedef struct reset_command_s
240 int trst; /* trst/srst 0: deassert, 1: assert, -1: don't change */
244 typedef struct end_state_command_s
246 tap_state_t end_state; /* TAP state in which JTAG commands should finish */
247 } end_state_command_t;
249 typedef struct sleep_command_s
251 u32 us; /* number of microseconds to sleep */
254 typedef union jtag_command_container_u
256 scan_command_t* scan;
257 statemove_command_t* statemove;
258 pathmove_command_t* pathmove;
259 runtest_command_t* runtest;
260 stableclocks_command_t* stableclocks;
261 reset_command_t* reset;
262 end_state_command_t* end_state;
263 sleep_command_t* sleep;
264 } jtag_command_container_t;
266 enum jtag_command_type {
274 JTAG_STABLECLOCKS = 8
277 typedef struct jtag_command_s
279 jtag_command_container_t cmd;
280 enum jtag_command_type type;
281 struct jtag_command_s* next;
284 extern jtag_command_t* jtag_command_queue;
286 /* forward declaration */
287 typedef struct jtag_tap_event_action_s jtag_tap_event_action_t;
289 /* this is really: typedef jtag_tap_t */
290 /* But - the typedef is done in "types.h" */
291 /* due to "forward decloration reasons" */
296 const char* dotted_name;
297 int abs_chain_position;
299 int ir_length; /* size of instruction register */
300 u32 ir_capture_value;
301 u8* expected; /* Capture-IR expected value */
303 u8* expected_mask; /* Capture-IR expected mask */
304 u32 idcode; /* device identification code */
305 u32* expected_ids; /* Array of expected identification codes */
306 u8 expected_ids_cnt; /* Number of expected identification codes */
307 u8* cur_instr; /* current instruction */
308 int bypass; /* bypass register selected */
310 jtag_tap_event_action_t* event_action;
312 jtag_tap_t* next_tap;
314 extern jtag_tap_t* jtag_AllTaps(void);
315 extern jtag_tap_t* jtag_TapByPosition(int n);
316 extern jtag_tap_t* jtag_TapByPosition(int n);
317 extern jtag_tap_t* jtag_TapByString(const char* dotted_name);
318 extern jtag_tap_t* jtag_TapByJimObj(Jim_Interp* interp, Jim_Obj* obj);
319 extern jtag_tap_t* jtag_TapByAbsPosition(int abs_position);
320 extern int jtag_NumEnabledTaps(void);
321 extern int jtag_NumTotalTaps(void);
323 static __inline__ jtag_tap_t* jtag_NextEnabledTap(jtag_tap_t* p)
327 /* start at the head of list */
332 /* start *after* this one */
351 enum reset_line_mode {
352 LINE_OPEN_DRAIN = 0x0,
353 LINE_PUSH_PULL = 0x1,
356 typedef struct jtag_interface_s
360 /* queued command execution
362 int (*execute_queue)(void);
364 /* interface initalization
366 int (*speed)(int speed);
367 int (*register_commands)(struct command_context_s* cmd_ctx);
371 /* returns JTAG maxium speed for KHz. 0=RTCK. The function returns
372 * a failure if it can't support the KHz/RTCK.
374 * WARNING!!!! if RTCK is *slow* then think carefully about
375 * whether you actually want to support this in the driver.
376 * Many target scripts are written to handle the absence of RTCK
377 * and use a fallback kHz TCK.
379 int (*khz)(int khz, int* jtag_speed);
381 /* returns the KHz for the provided JTAG speed. 0=RTCK. The function returns
382 * a failure if it can't support the KHz/RTCK. */
383 int (*speed_div)(int speed, int* khz);
385 /* Read and clear the power dropout flag. Note that a power dropout
386 * can be transitionary, easily much less than a ms.
388 * So to find out if the power is *currently* on, you must invoke
389 * this method twice. Once to clear the power dropout flag and a
390 * second time to read the current state.
392 * Currently the default implementation is never to detect power dropout.
394 int (*power_dropout)(int* power_dropout);
396 /* Read and clear the srst asserted detection flag.
398 * NB!!!! like power_dropout this does *not* read the current
399 * state. srst assertion is transitionary and *can* be much
402 int (*srst_asserted)(int* srst_asserted);
409 extern char* jtag_event_strings[];
411 enum jtag_tap_event {
412 JTAG_TAP_EVENT_ENABLE,
413 JTAG_TAP_EVENT_DISABLE
416 extern const Jim_Nvp nvp_jtag_tap_event[];
418 struct jtag_tap_event_action_s
420 enum jtag_tap_event event;
422 jtag_tap_event_action_t* next;
425 extern int jtag_trst;
426 extern int jtag_srst;
428 typedef struct jtag_event_callback_s
430 int (*callback)(enum jtag_event event, void* priv);
432 struct jtag_event_callback_s* next;
433 } jtag_event_callback_t;
435 extern jtag_event_callback_t* jtag_event_callbacks;
437 extern jtag_interface_t* jtag; /* global pointer to configured JTAG interface */
439 extern int jtag_speed;
440 extern int jtag_speed_post_reset;
444 RESET_HAS_TRST = 0x1,
445 RESET_HAS_SRST = 0x2,
446 RESET_TRST_AND_SRST = 0x3,
447 RESET_SRST_PULLS_TRST = 0x4,
448 RESET_TRST_PULLS_SRST = 0x8,
449 RESET_TRST_OPEN_DRAIN = 0x10,
450 RESET_SRST_PUSH_PULL = 0x20,
453 extern enum reset_types jtag_reset_config;
455 /* initialize interface upon startup. A successful no-op
456 * upon subsequent invocations
458 extern int jtag_interface_init(struct command_context_s* cmd_ctx);
460 /* initialize JTAG chain using only a RESET reset. If init fails,
463 extern int jtag_init(struct command_context_s* cmd_ctx);
465 /* reset, then initialize JTAG chain */
466 extern int jtag_init_reset(struct command_context_s* cmd_ctx);
467 extern int jtag_register_commands(struct command_context_s* cmd_ctx);
469 /* JTAG interface, can be implemented with a software or hardware fifo
471 * TAP_DRSHIFT and TAP_IRSHIFT are illegal end states. TAP_DRSHIFT/IRSHIFT as end states
472 * can be emulated by using a larger scan.
474 * Code that is relatively insensitive to the path(as long
475 * as it is JTAG compliant) taken through state machine can use
476 * endstate for jtag_add_xxx_scan(). Otherwise the pause state must be
477 * specified as end state and a subsequent jtag_add_pathmove() must
481 extern void jtag_add_ir_scan(int num_fields, scan_field_t* fields, tap_state_t endstate);
482 extern int interface_jtag_add_ir_scan(int num_fields, scan_field_t* fields, tap_state_t endstate);
483 extern void jtag_add_dr_scan(int num_fields, scan_field_t* fields, tap_state_t endstate);
484 extern int interface_jtag_add_dr_scan(int num_fields, scan_field_t* fields, tap_state_t endstate);
485 extern void jtag_add_plain_ir_scan(int num_fields, scan_field_t* fields, tap_state_t endstate);
486 extern int interface_jtag_add_plain_ir_scan(int num_fields, scan_field_t* fields, tap_state_t endstate);
487 extern void jtag_add_plain_dr_scan(int num_fields, scan_field_t* fields, tap_state_t endstate);
488 extern int interface_jtag_add_plain_dr_scan(int num_fields, scan_field_t* fields, tap_state_t endstate);
490 /* run a TAP_RESET reset. End state is TAP_RESET, regardless
493 extern void jtag_add_tlr(void);
494 extern int interface_jtag_add_tlr(void);
496 /* Do not use jtag_add_pathmove() unless you need to, but do use it
499 * DANGER! If the target is dependent upon a particular sequence
500 * of transitions for things to work correctly(e.g. as a workaround
501 * for an errata that contradicts the JTAG standard), then pathmove
502 * must be used, even if some jtag interfaces happen to use the
503 * desired path. Worse, the jtag interface used for testing a
504 * particular implementation, could happen to use the "desired"
505 * path when transitioning to/from end
508 * A list of unambigious single clock state transitions, not
509 * all drivers can support this, but it is required for e.g.
510 * XScale and Xilinx support
512 * Note! TAP_RESET must not be used in the path!
514 * Note that the first on the list must be reachable
515 * via a single transition from the current state.
517 * All drivers are required to implement jtag_add_pathmove().
518 * However, if the pathmove sequence can not be precisely
519 * executed, an interface_jtag_add_pathmove() or jtag_execute_queue()
520 * must return an error. It is legal, but not recommended, that
521 * a driver returns an error in all cases for a pathmove if it
522 * can only implement a few transitions and therefore
523 * a partial implementation of pathmove would have little practical
526 extern void jtag_add_pathmove(int num_states, tap_state_t* path);
527 extern int interface_jtag_add_pathmove(int num_states, tap_state_t* path);
529 /* go to TAP_IDLE, if we're not already there and cycle
530 * precisely num_cycles in the TAP_IDLE after which move
531 * to the end state, if it is != TAP_IDLE
533 * nb! num_cycles can be 0, in which case the fn will navigate
534 * to endstate via TAP_IDLE
536 extern void jtag_add_runtest(int num_cycles, tap_state_t endstate);
537 extern int interface_jtag_add_runtest(int num_cycles, tap_state_t endstate);
539 /* A reset of the TAP state machine can be requested.
541 * Whether tms or trst reset is used depends on the capabilities of
542 * the target and jtag interface(reset_config command configures this).
544 * srst can driver a reset of the TAP state machine and vice
547 * Application code may need to examine value of jtag_reset_config
548 * to determine the proper codepath
550 * DANGER! Even though srst drives trst, trst might not be connected to
551 * the interface, and it might actually be *harmful* to assert trst in this case.
553 * This is why combinations such as "reset_config srst_only srst_pulls_trst"
556 * only req_tlr_or_trst and srst can have a transition for a
557 * call as the effects of transitioning both at the "same time"
558 * are undefined, but when srst_pulls_trst or vice versa,
559 * then trst & srst *must* be asserted together.
561 extern void jtag_add_reset(int req_tlr_or_trst, int srst);
563 /* this drives the actual srst and trst pins. srst will always be 0
564 * if jtag_reset_config & RESET_SRST_PULLS_TRST != 0 and ditto for
567 * the higher level jtag_add_reset will invoke jtag_add_tlr() if
570 extern int interface_jtag_add_reset(int trst, int srst);
571 extern void jtag_add_end_state(tap_state_t endstate);
572 extern int interface_jtag_add_end_state(tap_state_t endstate);
573 extern void jtag_add_sleep(u32 us);
574 extern int interface_jtag_add_sleep(u32 us);
578 * Function jtag_add_stable_clocks
579 * first checks that the state in which the clocks are to be issued is
580 * stable, then queues up clock_count clocks for transmission.
582 void jtag_add_clocks(int num_cycles);
583 int interface_jtag_add_clocks(int num_cycles);
587 * For software FIFO implementations, the queued commands can be executed
588 * during this call or earlier. A sw queue might decide to push out
589 * some of the jtag_add_xxx() operations once the queue is "big enough".
591 * This fn will return an error code if any of the prior jtag_add_xxx()
592 * calls caused a failure, e.g. check failure. Note that it does not
593 * matter if the operation was executed *before* jtag_execute_queue(),
594 * jtag_execute_queue() will still return an error code.
596 * All jtag_add_xxx() calls that have in_handler!=NULL will have been
597 * executed when this fn returns, but if what has been queued only
598 * clocks data out, without reading anything back, then JTAG could
599 * be running *after* jtag_execute_queue() returns. The API does
600 * not define a way to flush a hw FIFO that runs *after*
601 * jtag_execute_queue() returns.
603 * jtag_add_xxx() commands can either be executed immediately or
604 * at some time between the jtag_add_xxx() fn call and jtag_execute_queue().
606 extern int jtag_execute_queue(void);
608 /* can be implemented by hw+sw */
609 extern int interface_jtag_execute_queue(void);
610 extern int jtag_power_dropout(int* dropout);
611 extern int jtag_srst_asserted(int* srst_asserted);
613 /* JTAG support functions */
614 extern void jtag_set_check_value(scan_field_t* field, u8* value, u8* mask, error_handler_t* in_error_handler);
615 extern enum scan_type jtag_scan_type(scan_command_t* cmd);
616 extern int jtag_scan_size(scan_command_t* cmd);
617 extern int jtag_read_buffer(u8* buffer, scan_command_t* cmd);
618 extern int jtag_build_buffer(scan_command_t* cmd, u8** buffer);
620 extern void jtag_sleep(u32 us);
621 extern int jtag_call_event_callbacks(enum jtag_event event);
622 extern int jtag_register_event_callback(int (* callback)(enum jtag_event event, void* priv), void* priv);
624 extern int jtag_verify_capture_ir;
626 void jtag_tap_handle_event(jtag_tap_t* tap, enum jtag_tap_event e);
629 * JTAG subsystem uses codes between -100 and -199 */
631 #define ERROR_JTAG_INIT_FAILED (-100)
632 #define ERROR_JTAG_INVALID_INTERFACE (-101)
633 #define ERROR_JTAG_NOT_IMPLEMENTED (-102)
634 #define ERROR_JTAG_TRST_ASSERTED (-103)
635 #define ERROR_JTAG_QUEUE_FAILED (-104)
636 #define ERROR_JTAG_NOT_STABLE_STATE (-105)
637 #define ERROR_JTAG_DEVICE_ERROR (-107)
640 /* this allows JTAG devices to implement the entire jtag_xxx() layer in hw/sw */
641 #ifdef HAVE_JTAG_MINIDRIVER_H
642 /* Here a #define MINIDRIVER() and an inline version of hw fifo interface_jtag_add_dr_out can be defined */
643 #include "jtag_minidriver.h"
644 #define MINIDRIVER(a) notused ## a
646 #define MINIDRIVER(a) a
648 /* jtag_add_dr_out() is a faster version of jtag_add_dr_scan()
650 * Current or end_state can not be TAP_RESET. end_state can be TAP_INVALID
652 * num_bits[i] is the number of bits to clock out from value[i] LSB first.
654 * If the device is in bypass, then that is an error condition in
655 * the caller code that is not detected by this fn, whereas jtag_add_dr_scan()
656 * does detect it. Similarly if the device is not in bypass, data must
659 * If anything fails, then jtag_error will be set and jtag_execute() will
660 * return an error. There is no way to determine if there was a failure
661 * during this function call.
663 * Note that this jtag_add_dr_out can be defined as an inline function.
665 extern void interface_jtag_add_dr_out(jtag_tap_t* tap, int num_fields, const int* num_bits, const u32* value,
666 tap_state_t end_state);
670 static __inline__ void jtag_add_dr_out(jtag_tap_t* tap, int num_fields, const int* num_bits, const u32* value,
671 tap_state_t end_state)
673 if (end_state != TAP_INVALID)
674 cmd_queue_end_state = end_state;
675 cmd_queue_cur_state = cmd_queue_end_state;
676 interface_jtag_add_dr_out(tap, num_fields, num_bits, value, cmd_queue_end_state);