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"
34 #define _DEBUG_JTAG_IO_
37 /* 16 Tap States, from page 21 of ASSET InterTech, Inc.'s svf.pdf
39 typedef enum tap_state
41 TAP_RESET = 0x0, TAP_IDLE = 0x8,
42 TAP_DRSELECT = 0x1, TAP_DRCAPTURE = 0x2, TAP_DRSHIFT = 0x3, TAP_DREXIT1 = 0x4,
43 TAP_DRPAUSE = 0x5, TAP_DREXIT2 = 0x6, TAP_DRUPDATE = 0x7,
44 TAP_IRSELECT = 0x9, TAP_IRCAPTURE = 0xa, TAP_IRSHIFT = 0xb, TAP_IREXIT1 = 0xc,
45 TAP_IRPAUSE = 0xd, TAP_IREXIT2 = 0xe, TAP_IRUPDATE = 0xf
48 typedef struct tap_transition_s
54 extern int tap_move_map[16]; /* map 16 TAP states to 6 stable states */
55 extern u8 tap_move[6][6]; /* value scanned to TMS to move from one of six stable states to another */
56 extern tap_transition_t tap_transitions[16]; /* describe the TAP state diagram */
58 extern enum tap_state end_state; /* finish DR scans in dr_end_state */
59 extern enum tap_state cur_state; /* current TAP state */
61 extern enum tap_state cmd_queue_end_state; /* finish DR scans in dr_end_state */
62 extern enum tap_state cmd_queue_cur_state; /* current TAP state */
64 #define TAP_MOVE(from, to) tap_move[tap_move_map[from]][tap_move_map[to]]
66 typedef void * error_handler_t; /* Later on we can delete error_handler_t, but keep it for now to make patches more readable */
69 typedef int (*in_handler_t)(u8 *in_value, void *priv, struct scan_field_s *field);
71 typedef struct scan_field_s
73 jtag_tap_t *tap; /* tap pointer this instruction refers to */
74 int num_bits; /* number of bits this field specifies (up to 32) */
75 u8 *out_value; /* value to be scanned into the device */
76 u8 *out_mask; /* only masked bits care */
77 u8 *in_value; /* pointer to a 32-bit memory location to take data scanned out */
78 /* in_check_value/mask, in_handler_error_handler, in_handler_priv can be used by the in handler, otherwise they contain garbage */
79 u8 *in_check_value; /* used to validate scan results */
80 u8 *in_check_mask; /* check specified bits against check_value */
81 in_handler_t in_handler;/* process received buffer using this handler */
82 void *in_handler_priv; /* additional information for the in_handler */
87 /* IN: from device to host, OUT: from host to device */
88 SCAN_IN = 1, SCAN_OUT = 2, SCAN_IO = 3
91 typedef struct scan_command_s
93 int ir_scan; /* instruction/not data scan */
94 int num_fields; /* number of fields in *fields array */
95 scan_field_t *fields; /* pointer to an array of data scan fields */
96 enum tap_state end_state; /* TAP state in which JTAG commands should finish */
99 typedef struct statemove_command_s
101 enum tap_state end_state; /* TAP state in which JTAG commands should finish */
102 } statemove_command_t;
104 typedef struct pathmove_command_s
106 int num_states; /* number of states in *path */
107 enum tap_state *path; /* states that have to be passed */
108 } pathmove_command_t;
110 typedef struct runtest_command_s
112 int num_cycles; /* number of cycles that should be spent in Run-Test/Idle */
113 enum tap_state end_state; /* TAP state in which JTAG commands should finish */
117 typedef struct stableclocks_command_s
119 int num_cycles; /* number of clock cycles that should be sent */
120 } stableclocks_command_t;
123 typedef struct reset_command_s
125 int trst; /* trst/srst 0: deassert, 1: assert, -1: don't change */
129 typedef struct end_state_command_s
131 enum tap_state end_state; /* TAP state in which JTAG commands should finish */
132 } end_state_command_t;
134 typedef struct sleep_command_s
136 u32 us; /* number of microseconds to sleep */
139 typedef union jtag_command_container_u
141 scan_command_t *scan;
142 statemove_command_t *statemove;
143 pathmove_command_t *pathmove;
144 runtest_command_t *runtest;
145 stableclocks_command_t *stableclocks;
146 reset_command_t *reset;
147 end_state_command_t *end_state;
148 sleep_command_t *sleep;
149 } jtag_command_container_t;
151 enum jtag_command_type
154 JTAG_STATEMOVE = 2, JTAG_RUNTEST = 3,
155 JTAG_RESET = 4, JTAG_END_STATE = 5,
156 JTAG_PATHMOVE = 6, JTAG_SLEEP = 7,
157 JTAG_STABLECLOCKS = 8
160 typedef struct jtag_command_s
162 jtag_command_container_t cmd;
163 enum jtag_command_type type;
164 struct jtag_command_s *next;
167 extern jtag_command_t *jtag_command_queue;
169 /* forward declaration */
170 typedef struct jtag_tap_event_action_s jtag_tap_event_action_t;
172 /* this is really: typedef jtag_tap_t */
173 /* But - the typedef is done in "types.h" */
174 /* due to "forward decloration reasons" */
179 const char *dotted_name;
180 int abs_chain_position;
182 int ir_length; /* size of instruction register */
183 u32 ir_capture_value;
184 u8 *expected; /* Capture-IR expected value */
186 u8 *expected_mask; /* Capture-IR expected mask */
187 u32 idcode; /* device identification code */
188 u32 *expected_ids; /* Array of expected identification codes */
189 u8 expected_ids_cnt;/* Number of expected identification codes */
190 u8 *cur_instr; /* current instruction */
191 int bypass; /* bypass register selected */
193 jtag_tap_event_action_t *event_action;
195 jtag_tap_t *next_tap;
197 extern jtag_tap_t *jtag_AllTaps(void);
198 extern jtag_tap_t *jtag_TapByPosition(int n);
199 extern jtag_tap_t *jtag_TapByPosition(int n);
200 extern jtag_tap_t *jtag_TapByString(const char *dotted_name);
201 extern jtag_tap_t *jtag_TapByJimObj(Jim_Interp *interp, Jim_Obj *obj);
202 extern jtag_tap_t *jtag_TapByAbsPosition(int abs_position);
203 extern int jtag_NumEnabledTaps(void);
204 extern int jtag_NumTotalTaps(void);
206 static __inline__ jtag_tap_t *
207 jtag_NextEnabledTap( jtag_tap_t *p )
210 /* start at the head of list */
213 /* start *after* this one */
228 LINE_OPEN_DRAIN = 0x0,
229 LINE_PUSH_PULL = 0x1,
232 typedef struct jtag_interface_s
236 /* queued command execution
238 int (*execute_queue)(void);
240 /* interface initalization
242 int (*speed)(int speed);
243 int (*register_commands)(struct command_context_s *cmd_ctx);
246 /* returns JTAG maxium speed for KHz. 0=RTCK. The function returns
247 a failure if it can't support the KHz/RTCK.
249 WARNING!!!! if RTCK is *slow* then think carefully about
250 whether you actually want to support this in the driver.
251 Many target scripts are written to handle the absence of RTCK
252 and use a fallback kHz TCK.
254 int (*khz)(int khz, int *jtag_speed);
255 /* returns the KHz for the provided JTAG speed. 0=RTCK. The function returns
256 a failure if it can't support the KHz/RTCK. */
257 int (*speed_div)(int speed, int *khz);
259 /* Read and clear the power dropout flag. Note that a power dropout
260 can be transitionary, easily much less than a ms.
262 So to find out if the power is *currently* on, you must invoke
263 this method twice. Once to clear the power dropout flag and a
264 second time to read the current state.
266 Currently the default implementation is never to detect power dropout.
268 int (*power_dropout)(int *power_dropout);
269 /* Read and clear the srst asserted detection flag.
271 * NB!!!! like power_dropout this does *not* read the current
272 * state. srst assertion is transitionary and *can* be much
275 int (*srst_asserted)(int *srst_asserted);
284 extern char * jtag_event_strings[];
288 JTAG_TAP_EVENT_ENABLE,
289 JTAG_TAP_EVENT_DISABLE
292 extern const Jim_Nvp nvp_jtag_tap_event[];
294 struct jtag_tap_event_action_s {
295 enum jtag_tap_event event;
297 jtag_tap_event_action_t *next;
300 extern int jtag_trst;
301 extern int jtag_srst;
303 typedef struct jtag_event_callback_s
305 int (*callback)(enum jtag_event event, void *priv);
307 struct jtag_event_callback_s *next;
308 } jtag_event_callback_t;
310 extern jtag_event_callback_t *jtag_event_callbacks;
312 extern jtag_interface_t *jtag; /* global pointer to configured JTAG interface */
313 extern enum tap_state end_state;
314 extern enum tap_state cur_state;
316 extern int jtag_speed;
317 extern int jtag_speed_post_reset;
322 RESET_HAS_TRST = 0x1,
323 RESET_HAS_SRST = 0x2,
324 RESET_TRST_AND_SRST = 0x3,
325 RESET_SRST_PULLS_TRST = 0x4,
326 RESET_TRST_PULLS_SRST = 0x8,
327 RESET_TRST_OPEN_DRAIN = 0x10,
328 RESET_SRST_PUSH_PULL = 0x20,
331 extern enum reset_types jtag_reset_config;
333 /* initialize interface upon startup. A successful no-op
334 * upon subsequent invocations
336 extern int jtag_interface_init(struct command_context_s *cmd_ctx);
337 /* initialize JTAG chain using only a RESET reset. If init fails,
340 extern int jtag_init(struct command_context_s *cmd_ctx);
341 /* reset, then initialize JTAG chain */
342 extern int jtag_init_reset(struct command_context_s *cmd_ctx);
343 extern int jtag_register_commands(struct command_context_s *cmd_ctx);
345 /* JTAG interface, can be implemented with a software or hardware fifo
347 * TAP_DRSHIFT and TAP_IRSHIFT are illegal end states. TAP_DRSHIFT/IRSHIFT as end states
348 * can be emulated by using a larger scan.
350 * Code that is relatively insensitive to the path(as long
351 * as it is JTAG compliant) taken through state machine can use
352 * endstate for jtag_add_xxx_scan(). Otherwise the pause state must be
353 * specified as end state and a subsequent jtag_add_pathmove() must
357 extern void jtag_add_ir_scan(int num_fields, scan_field_t *fields, enum tap_state endstate);
358 extern int interface_jtag_add_ir_scan(int num_fields, scan_field_t *fields, enum tap_state endstate);
359 extern void jtag_add_dr_scan(int num_fields, scan_field_t *fields, enum tap_state endstate);
360 extern int interface_jtag_add_dr_scan(int num_fields, scan_field_t *fields, enum tap_state endstate);
361 extern void jtag_add_plain_ir_scan(int num_fields, scan_field_t *fields, enum tap_state endstate);
362 extern int interface_jtag_add_plain_ir_scan(int num_fields, scan_field_t *fields, enum tap_state endstate);
363 extern void jtag_add_plain_dr_scan(int num_fields, scan_field_t *fields, enum tap_state endstate);
364 extern int interface_jtag_add_plain_dr_scan(int num_fields, scan_field_t *fields, enum tap_state endstate);
365 /* run a TAP_RESET reset. End state is TAP_RESET, regardless
368 extern void jtag_add_tlr(void);
369 extern int interface_jtag_add_tlr(void);
370 /* Do not use jtag_add_pathmove() unless you need to, but do use it
373 * DANGER! If the target is dependent upon a particular sequence
374 * of transitions for things to work correctly(e.g. as a workaround
375 * for an errata that contradicts the JTAG standard), then pathmove
376 * must be used, even if some jtag interfaces happen to use the
377 * desired path. Worse, the jtag interface used for testing a
378 * particular implementation, could happen to use the "desired"
379 * path when transitioning to/from end
382 * A list of unambigious single clock state transitions, not
383 * all drivers can support this, but it is required for e.g.
384 * XScale and Xilinx support
386 * Note! TAP_RESET must not be used in the path!
388 * Note that the first on the list must be reachable
389 * via a single transition from the current state.
391 * All drivers are required to implement jtag_add_pathmove().
392 * However, if the pathmove sequence can not be precisely
393 * executed, an interface_jtag_add_pathmove() or jtag_execute_queue()
394 * must return an error. It is legal, but not recommended, that
395 * a driver returns an error in all cases for a pathmove if it
396 * can only implement a few transitions and therefore
397 * a partial implementation of pathmove would have little practical
400 extern void jtag_add_pathmove(int num_states, enum tap_state *path);
401 extern int interface_jtag_add_pathmove(int num_states, enum tap_state *path);
402 /* go to TAP_IDLE, if we're not already there and cycle
403 * precisely num_cycles in the TAP_IDLE after which move
404 * to the end state, if it is != TAP_IDLE
406 * nb! num_cycles can be 0, in which case the fn will navigate
407 * to endstate via TAP_IDLE
409 extern void jtag_add_runtest(int num_cycles, enum tap_state endstate);
410 extern int interface_jtag_add_runtest(int num_cycles, enum tap_state endstate);
411 /* A reset of the TAP state machine can be requested.
413 * Whether tms or trst reset is used depends on the capabilities of
414 * the target and jtag interface(reset_config command configures this).
416 * srst can driver a reset of the TAP state machine and vice
419 * Application code may need to examine value of jtag_reset_config
420 * to determine the proper codepath
422 * DANGER! Even though srst drives trst, trst might not be connected to
423 * the interface, and it might actually be *harmful* to assert trst in this case.
425 * This is why combinations such as "reset_config srst_only srst_pulls_trst"
428 * only req_tlr_or_trst and srst can have a transition for a
429 * call as the effects of transitioning both at the "same time"
430 * are undefined, but when srst_pulls_trst or vice versa,
431 * then trst & srst *must* be asserted together.
433 extern void jtag_add_reset(int req_tlr_or_trst, int srst);
434 /* this drives the actual srst and trst pins. srst will always be 0
435 * if jtag_reset_config & RESET_SRST_PULLS_TRST != 0 and ditto for
438 * the higher level jtag_add_reset will invoke jtag_add_tlr() if
441 extern int interface_jtag_add_reset(int trst, int srst);
442 extern void jtag_add_end_state(enum tap_state endstate);
443 extern int interface_jtag_add_end_state(enum tap_state endstate);
444 extern void jtag_add_sleep(u32 us);
445 extern int interface_jtag_add_sleep(u32 us);
449 * Function jtag_add_stable_clocks
450 * first checks that the state in which the clocks are to be issued is
451 * stable, then queues up clock_count clocks for transmission.
453 void jtag_add_clocks( int num_cycles );
454 int interface_jtag_add_clocks( int num_cycles );
458 * For software FIFO implementations, the queued commands can be executed
459 * during this call or earlier. A sw queue might decide to push out
460 * some of the jtag_add_xxx() operations once the queue is "big enough".
462 * This fn will return an error code if any of the prior jtag_add_xxx()
463 * calls caused a failure, e.g. check failure. Note that it does not
464 * matter if the operation was executed *before* jtag_execute_queue(),
465 * jtag_execute_queue() will still return an error code.
467 * All jtag_add_xxx() calls that have in_handler!=NULL will have been
468 * executed when this fn returns, but if what has been queued only
469 * clocks data out, without reading anything back, then JTAG could
470 * be running *after* jtag_execute_queue() returns. The API does
471 * not define a way to flush a hw FIFO that runs *after*
472 * jtag_execute_queue() returns.
474 * jtag_add_xxx() commands can either be executed immediately or
475 * at some time between the jtag_add_xxx() fn call and jtag_execute_queue().
477 extern int jtag_execute_queue(void);
478 /* can be implemented by hw+sw */
479 extern int interface_jtag_execute_queue(void);
480 extern int jtag_power_dropout(int *dropout);
481 extern int jtag_srst_asserted(int *srst_asserted);
483 /* JTAG support functions */
484 extern void jtag_set_check_value(scan_field_t *field, u8 *value, u8 *mask, error_handler_t *in_error_handler);
485 extern enum scan_type jtag_scan_type(scan_command_t *cmd);
486 extern int jtag_scan_size(scan_command_t *cmd);
487 extern int jtag_read_buffer(u8 *buffer, scan_command_t *cmd);
488 extern int jtag_build_buffer(scan_command_t *cmd, u8 **buffer);
490 extern void jtag_sleep(u32 us);
491 extern int jtag_call_event_callbacks(enum jtag_event event);
492 extern int jtag_register_event_callback(int (*callback)(enum jtag_event event, void *priv), void *priv);
494 extern int jtag_verify_capture_ir;
496 void jtag_tap_handle_event( jtag_tap_t * tap, enum jtag_tap_event e);
499 * JTAG subsystem uses codes between -100 and -199 */
501 #define ERROR_JTAG_INIT_FAILED (-100)
502 #define ERROR_JTAG_INVALID_INTERFACE (-101)
503 #define ERROR_JTAG_NOT_IMPLEMENTED (-102)
504 #define ERROR_JTAG_TRST_ASSERTED (-103)
505 #define ERROR_JTAG_QUEUE_FAILED (-104)
506 #define ERROR_JTAG_DEVICE_ERROR (-107)
508 /* this allows JTAG devices to implement the entire jtag_xxx() layer in hw/sw */
509 #ifdef HAVE_JTAG_MINIDRIVER_H
510 /* Here a #define MINIDRIVER() and an inline version of hw fifo interface_jtag_add_dr_out can be defined */
511 #include "jtag_minidriver.h"
512 #define MINIDRIVER(a) notused ## a
514 #define MINIDRIVER(a) a
515 /* jtag_add_dr_out() is a faster version of jtag_add_dr_scan()
517 * Current or end_state can not be TAP_RESET. end_state can be -1
519 * num_bits[i] is the number of bits to clock out from value[i] LSB first.
521 * If the device is in bypass, then that is an error condition in
522 * the caller code that is not detected by this fn, whereas jtag_add_dr_scan()
523 * does detect it. Similarly if the device is not in bypass, data must
526 * If anything fails, then jtag_error will be set and jtag_execute() will
527 * return an error. There is no way to determine if there was a failure
528 * during this function call.
530 * Note that this jtag_add_dr_out can be defined as an inline function.
532 extern void interface_jtag_add_dr_out(jtag_tap_t *tap,
536 enum tap_state end_state);
539 static __inline__ void jtag_add_dr_out(jtag_tap_t *tap,
543 enum tap_state end_state)
546 cmd_queue_end_state=end_state;
547 cmd_queue_cur_state=cmd_queue_end_state;
548 interface_jtag_add_dr_out(tap, num_fields, num_bits, value, cmd_queue_end_state);
552 * Function jtag_state_name
553 * Returns a string suitable for display representing the JTAG tap_state
555 const char* jtag_state_name(enum tap_state state);