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;
107 /// The TAP state in which DR scans should end.
108 extern tap_state_t cmd_queue_end_state;
111 * This structure defines a single scan field in the scan. It provides
112 * fields for the field's width and pointers to scan input and output
115 * In addition, this structure includes a value and mask that is used by
116 * jtag_add_dr_scan_check() to validate the value that was scanned out.
118 * The allocated, modified, and intmp fields are internal work space.
120 typedef struct scan_field_s
122 /// A pointer to the tap structure to which this field refers.
125 /// The number of bits this field specifies (up to 32)
127 /// A pointer to value to be scanned into the device
129 /// A pointer to a 32-bit memory location for data scanned out
132 /// The value used to check the data scanned out.
134 /// The mask to go with check_value
137 /// in_value has been allocated for the queue
139 /// Indicates we modified the in_value.
141 /// temporary storage for performing value checks synchronously
145 typedef struct jtag_tap_event_action_s jtag_tap_event_action_t;
147 /* this is really: typedef jtag_tap_t */
148 /* But - the typedef is done in "types.h" */
149 /* due to "forward decloration reasons" */
154 const char* dotted_name;
155 int abs_chain_position;
156 /// Is this TAP enabled?
158 int ir_length; /**< size of instruction register */
159 u32 ir_capture_value;
160 u8* expected; /**< Capture-IR expected value */
162 u8* expected_mask; /**< Capture-IR expected mask */
164 /**< device identification code */
166 /// Array of expected identification codes */
168 /// Number of expected identification codes
171 /// current instruction
173 /// Bypass register selected
176 jtag_tap_event_action_t *event_action;
178 jtag_tap_t* next_tap;
180 extern jtag_tap_t* jtag_AllTaps(void);
181 extern jtag_tap_t* jtag_TapByPosition(int n);
182 extern jtag_tap_t* jtag_TapByString(const char* dotted_name);
183 extern jtag_tap_t* jtag_TapByJimObj(Jim_Interp* interp, Jim_Obj* obj);
184 extern jtag_tap_t* jtag_TapByAbsPosition(int abs_position);
185 extern int jtag_NumEnabledTaps(void);
186 extern int jtag_NumTotalTaps(void);
188 static __inline__ jtag_tap_t* jtag_NextEnabledTap(jtag_tap_t* p)
192 /* start at the head of list */
197 /* start *after* this one */
216 enum reset_line_mode {
217 LINE_OPEN_DRAIN = 0x0,
218 LINE_PUSH_PULL = 0x1,
222 * There are three cases when JTAG_TRST_ASSERTED callback is invoked. The
223 * event is invoked *after* TRST is asserted(or queued rather). It is illegal
224 * to communicate with the JTAG interface during the callback(as there is
225 * currently a queue being built).
236 extern char* jtag_event_strings[];
238 enum jtag_tap_event {
239 JTAG_TAP_EVENT_ENABLE,
240 JTAG_TAP_EVENT_DISABLE
243 extern const Jim_Nvp nvp_jtag_tap_event[];
245 struct jtag_tap_event_action_s
247 enum jtag_tap_event event;
249 jtag_tap_event_action_t* next;
252 extern int jtag_trst;
253 extern int jtag_srst;
255 typedef struct jtag_event_callback_s
257 int (*callback)(enum jtag_event event, void* priv);
259 struct jtag_event_callback_s* next;
260 } jtag_event_callback_t;
262 extern jtag_event_callback_t* jtag_event_callbacks;
264 extern int jtag_speed;
265 extern int jtag_speed_post_reset;
269 RESET_HAS_TRST = 0x1,
270 RESET_HAS_SRST = 0x2,
271 RESET_TRST_AND_SRST = 0x3,
272 RESET_SRST_PULLS_TRST = 0x4,
273 RESET_TRST_PULLS_SRST = 0x8,
274 RESET_TRST_OPEN_DRAIN = 0x10,
275 RESET_SRST_PUSH_PULL = 0x20,
278 extern enum reset_types jtag_reset_config;
281 * Initialize interface upon startup. Return a successful no-op upon
282 * subsequent invocations.
284 extern int jtag_interface_init(struct command_context_s* cmd_ctx);
286 /// Shutdown the JTAG interface upon program exit.
287 extern int jtag_interface_quit(void);
290 * Initialize JTAG chain using only a RESET reset. If init fails,
293 extern int jtag_init(struct command_context_s* cmd_ctx);
295 /// reset, then initialize JTAG chain
296 extern int jtag_init_reset(struct command_context_s* cmd_ctx);
297 extern int jtag_register_commands(struct command_context_s* cmd_ctx);
301 * The JTAG interface can be implemented with a software or hardware fifo.
303 * TAP_DRSHIFT and TAP_IRSHIFT are illegal end states; however,
304 * TAP_DRSHIFT/IRSHIFT can be emulated as end states, by using longer
307 * Code that is relatively insensitive to the path taken through state
308 * machine (as long as it is JTAG compliant) can use @a endstate for
309 * jtag_add_xxx_scan(). Otherwise, the pause state must be specified as
310 * end state and a subsequent jtag_add_pathmove() must be issued.
313 extern void jtag_add_ir_scan(int num_fields, scan_field_t* fields, tap_state_t endstate);
315 * The same as jtag_add_ir_scan except no verification is performed out
318 extern void jtag_add_ir_scan_noverify(int num_fields, const scan_field_t *fields, tap_state_t state);
322 * Set in_value to point to 32 bits of memory to scan into. This
323 * function is a way to handle the case of synchronous and asynchronous
326 * In the event of an asynchronous queue execution the queue buffer
327 * allocation method is used, for the synchronous case the temporary 32
328 * bits come from the input field itself.
330 extern void jtag_alloc_in_value32(scan_field_t *field);
332 extern void jtag_add_dr_scan(int num_fields, const scan_field_t* fields, tap_state_t endstate);
333 /// A version of jtag_add_dr_scan() that uses the check_value/mask fields
334 extern void jtag_add_dr_scan_check(int num_fields, scan_field_t* fields, tap_state_t endstate);
335 extern void jtag_add_plain_ir_scan(int num_fields, const scan_field_t* fields, tap_state_t endstate);
336 extern void jtag_add_plain_dr_scan(int num_fields, const scan_field_t* fields, tap_state_t endstate);
340 * Defines a simple JTAG callback that can allow conversions on data
341 * scanned in from an interface.
343 * This callback should only be used for conversion that cannot fail.
344 * For conversion types or checks that can fail, use the more complete
345 * variant: jtag_callback_t.
347 typedef void (*jtag_callback1_t)(u8 *in);
349 /// A simpler version of jtag_add_callback4().
350 extern void jtag_add_callback(jtag_callback1_t, u8 *in);
354 * Defines the type of data passed to the jtag_callback_t interface.
355 * The underlying type must allow storing an @c int or pointer type.
357 typedef intptr_t jtag_callback_data_t;
360 * Defines the interface of the JTAG callback mechanism.
362 * @param in the pointer to the data clocked in
363 * @param data1 An integer big enough to use as an @c int or a pointer.
364 * @param data2 An integer big enough to use as an @c int or a pointer.
365 * @param data3 An integer big enough to use as an @c int or a pointer.
366 * @returns an error code
368 typedef int (*jtag_callback_t)(u8 *in, jtag_callback_data_t data1, jtag_callback_data_t data2, jtag_callback_data_t data3);
372 * This callback can be executed immediately the queue has been flushed.
374 * The JTAG queue can be executed synchronously or asynchronously.
375 * Typically for USB, the queue is executed asynchronously. For
376 * low-latency interfaces, the queue may be executed synchronously.
378 * The callback mechanism is very general and does not make many
379 * assumptions about what the callback does or what its arguments are.
380 * These callbacks are typically executed *after* the *entire* JTAG
381 * queue has been executed for e.g. USB interfaces, and they are
382 * guaranteeed to be invoked in the order that they were queued.
384 * If the execution of the queue fails before the callbacks, then --
385 * depending on driver implementation -- the callbacks may or may not be
386 * invoked. @todo Can we make this behavior consistent?
388 * The strange name is due to C's lack of overloading using function
391 * @param f The callback function to add.
392 * @param in Typically used to point to the data to operate on.
393 * Frequently this will be the data clocked in during a shift operation.
394 * @param data1 An integer big enough to use as an @c int or a pointer.
395 * @param data2 An integer big enough to use as an @c int or a pointer.
396 * @param data3 An integer big enough to use as an @c int or a pointer.
399 extern void jtag_add_callback4(jtag_callback_t f, u8 *in,
400 jtag_callback_data_t data1, jtag_callback_data_t data2,
401 jtag_callback_data_t data3);
405 * Run a TAP_RESET reset where the end state is TAP_RESET,
406 * regardless of the start state.
408 extern void jtag_add_tlr(void);
411 * Application code *must* assume that interfaces will
412 * implement transitions between states with different
413 * paths and path lengths through the state diagram. The
414 * path will vary across interface and also across versions
415 * of the same interface over time. Even if the OpenOCD code
416 * is unchanged, the actual path taken may vary over time
417 * and versions of interface firmware or PCB revisions.
419 * Use jtag_add_pathmove() when specific transition sequences
422 * Do not use jtag_add_pathmove() unless you need to, but do use it
425 * DANGER! If the target is dependent upon a particular sequence
426 * of transitions for things to work correctly(e.g. as a workaround
427 * for an errata that contradicts the JTAG standard), then pathmove
428 * must be used, even if some jtag interfaces happen to use the
429 * desired path. Worse, the jtag interface used for testing a
430 * particular implementation, could happen to use the "desired"
431 * path when transitioning to/from end
434 * A list of unambigious single clock state transitions, not
435 * all drivers can support this, but it is required for e.g.
436 * XScale and Xilinx support
438 * Note! TAP_RESET must not be used in the path!
440 * Note that the first on the list must be reachable
441 * via a single transition from the current state.
443 * All drivers are required to implement jtag_add_pathmove().
444 * However, if the pathmove sequence can not be precisely
445 * executed, an interface_jtag_add_pathmove() or jtag_execute_queue()
446 * must return an error. It is legal, but not recommended, that
447 * a driver returns an error in all cases for a pathmove if it
448 * can only implement a few transitions and therefore
449 * a partial implementation of pathmove would have little practical
452 extern void jtag_add_pathmove(int num_states, const tap_state_t* path);
455 * Goes to TAP_IDLE (if we're not already there), cycle
456 * precisely num_cycles in the TAP_IDLE state, after which move
457 * to @a endstate (unless it is also TAP_IDLE).
459 * @param num_cycles Number of cycles in TAP_IDLE state. This argument
460 * may be 0, in which case this routine will navigate to @a endstate
462 * @param endstate The final state.
464 extern void jtag_add_runtest(int num_cycles, tap_state_t endstate);
467 * A reset of the TAP state machine can be requested.
469 * Whether tms or trst reset is used depends on the capabilities of
470 * the target and jtag interface(reset_config command configures this).
472 * srst can driver a reset of the TAP state machine and vice
475 * Application code may need to examine value of jtag_reset_config
476 * to determine the proper codepath
478 * DANGER! Even though srst drives trst, trst might not be connected to
479 * the interface, and it might actually be *harmful* to assert trst in this case.
481 * This is why combinations such as "reset_config srst_only srst_pulls_trst"
484 * only req_tlr_or_trst and srst can have a transition for a
485 * call as the effects of transitioning both at the "same time"
486 * are undefined, but when srst_pulls_trst or vice versa,
487 * then trst & srst *must* be asserted together.
489 extern void jtag_add_reset(int req_tlr_or_trst, int srst);
493 * Function jtag_add_stable_clocks
495 * Set a global variable to \a state if \a state != TAP_INVALID.
497 * Return the value of the global variable.
500 extern tap_state_t jtag_add_end_state(tap_state_t state);
501 extern void jtag_add_sleep(u32 us);
505 * Function jtag_add_stable_clocks
506 * first checks that the state in which the clocks are to be issued is
507 * stable, then queues up clock_count clocks for transmission.
509 void jtag_add_clocks(int num_cycles);
513 * For software FIFO implementations, the queued commands can be executed
514 * during this call or earlier. A sw queue might decide to push out
515 * some of the jtag_add_xxx() operations once the queue is "big enough".
517 * This fn will return an error code if any of the prior jtag_add_xxx()
518 * calls caused a failure, e.g. check failure. Note that it does not
519 * matter if the operation was executed *before* jtag_execute_queue(),
520 * jtag_execute_queue() will still return an error code.
522 * All jtag_add_xxx() calls that have in_handler!=NULL will have been
523 * executed when this fn returns, but if what has been queued only
524 * clocks data out, without reading anything back, then JTAG could
525 * be running *after* jtag_execute_queue() returns. The API does
526 * not define a way to flush a hw FIFO that runs *after*
527 * jtag_execute_queue() returns.
529 * jtag_add_xxx() commands can either be executed immediately or
530 * at some time between the jtag_add_xxx() fn call and jtag_execute_queue().
532 extern int jtag_execute_queue(void);
534 /* same as jtag_execute_queue() but does not clear the error flag */
535 extern void jtag_execute_queue_noclear(void);
538 * The jtag_error variable is set when an error occurs while executing
541 * This flag can also be set from application code, if an error happens
542 * during processing that should be reported during jtag_execute_queue().
544 * It is cleared by jtag_execute_queue().
546 extern int jtag_error;
548 static __inline__ void jtag_set_error(int error)
550 if ((error==ERROR_OK)||(jtag_error!=ERROR_OK))
552 /* keep first error */
560 /* can be implemented by hw+sw */
561 extern int jtag_power_dropout(int* dropout);
562 extern int jtag_srst_asserted(int* srst_asserted);
564 /* JTAG support functions */
567 * Execute jtag queue and check value with an optional mask.
568 * @param field Pointer to scan field.
569 * @param value Pointer to scan value.
570 * @param mask Pointer to scan mask; may be NULL.
571 * @returns Nothing, but calls jtag_set_error() on any error.
573 extern void jtag_check_value_mask(scan_field_t *field, u8 *value, u8 *mask);
575 extern void jtag_sleep(u32 us);
576 extern int jtag_call_event_callbacks(enum jtag_event event);
577 extern int jtag_register_event_callback(int (* callback)(enum jtag_event event, void* priv), void* priv);
579 extern int jtag_verify_capture_ir;
581 void jtag_tap_handle_event(jtag_tap_t* tap, enum jtag_tap_event e);
584 * The JTAG subsystem defines a number of error codes,
585 * using codes between -100 and -199.
587 #define ERROR_JTAG_INIT_FAILED (-100)
588 #define ERROR_JTAG_INVALID_INTERFACE (-101)
589 #define ERROR_JTAG_NOT_IMPLEMENTED (-102)
590 #define ERROR_JTAG_TRST_ASSERTED (-103)
591 #define ERROR_JTAG_QUEUE_FAILED (-104)
592 #define ERROR_JTAG_NOT_STABLE_STATE (-105)
593 #define ERROR_JTAG_DEVICE_ERROR (-107)
596 * jtag_add_dr_out() is a version of jtag_add_dr_scan() which
597 * only scans data out. It operates on 32 bit integers instead
598 * of 8 bit, which makes it a better impedance match with
599 * the calling code which often operate on 32 bit integers.
601 * Current or end_state can not be TAP_RESET. end_state can be TAP_INVALID
603 * num_bits[i] is the number of bits to clock out from value[i] LSB first.
605 * If the device is in bypass, then that is an error condition in
606 * the caller code that is not detected by this fn, whereas
607 * jtag_add_dr_scan() does detect it. Similarly if the device is not in
608 * bypass, data must be passed to it.
610 * If anything fails, then jtag_error will be set and jtag_execute() will
611 * return an error. There is no way to determine if there was a failure
612 * during this function call.
614 * This is an inline fn to speed up embedded hosts. Also note that
615 * interface_jtag_add_dr_out() can be a *small* inline function for
618 * There is no jtag_add_dr_outin() version of this fn that also allows
619 * clocking data back in. Patches gladly accepted!
621 extern void jtag_add_dr_out(jtag_tap_t* tap,
622 int num_fields, const int* num_bits, const u32* value,
623 tap_state_t end_state);
627 * jtag_add_statemove() moves from the current state to @a goal_state.
629 * This function was originally designed to handle the XSTATE command
630 * from the XSVF specification.
632 * @param goal_state The final TAP state.
633 * @return ERROR_OK on success, or an error code on failure.
635 extern int jtag_add_statemove(tap_state_t goal_state);