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 #define _DEBUG_JTAG_IO_
37 * TLR - Test-Logic-Reset, RTI - Run-Test/Idle,
38 * SDS - Select-DR-Scan, CD - Capture-DR, SD - Shift-DR, E1D - Exit1-DR,
39 * PD - Pause-DR, E2D - Exit2-DR, UD - Update-DR,
40 * SIS - Select-IR-Scan, CI - Capture-IR, SI - Shift-IR, E1I - Exit1-IR,
41 * PI - Pause-IR, E2I - Exit2-IR, UI - Update-IR
45 TAP_TLR = 0x0, TAP_RTI = 0x8,
46 TAP_SDS = 0x1, TAP_CD = 0x2, TAP_SD = 0x3, TAP_E1D = 0x4,
47 TAP_PD = 0x5, TAP_E2D = 0x6, TAP_UD = 0x7,
48 TAP_SIS = 0x9, TAP_CI = 0xa, TAP_SI = 0xb, TAP_E1I = 0xc,
49 TAP_PI = 0xd, TAP_E2I = 0xe, TAP_UI = 0xf
52 typedef struct tap_transition_s
58 extern char* tap_state_strings[16];
59 extern int tap_move_map[16]; /* map 16 TAP states to 6 stable states */
60 extern u8 tap_move[6][6]; /* value scanned to TMS to move from one of six stable states to another */
61 extern tap_transition_t tap_transitions[16]; /* describe the TAP state diagram */
63 extern enum tap_state end_state; /* finish DR scans in dr_end_state */
64 extern enum tap_state cur_state; /* current TAP state */
66 extern enum tap_state cmd_queue_end_state; /* finish DR scans in dr_end_state */
67 extern enum tap_state cmd_queue_cur_state; /* current TAP state */
69 #define TAP_MOVE(from, to) tap_move[tap_move_map[from]][tap_move_map[to]]
71 typedef void * error_handler_t; /* Later on we can delete error_handler_t, but keep it for now to make patches more readable */
74 typedef int (*in_handler_t)(u8 *in_value, void *priv, struct scan_field_s *field);
76 typedef struct scan_field_s
78 int device; /* ordinal device number this instruction refers to */
79 int num_bits; /* number of bits this field specifies (up to 32) */
80 u8 *out_value; /* value to be scanned into the device */
81 u8 *out_mask; /* only masked bits care */
82 u8 *in_value; /* pointer to a 32-bit memory location to take data scanned out */
83 /* in_check_value/mask, in_handler_error_handler, in_handler_priv can be used by the in handler, otherwise they contain garbage */
84 u8 *in_check_value; /* used to validate scan results */
85 u8 *in_check_mask; /* check specified bits against check_value */
86 in_handler_t in_handler; /* process received buffer using this handler */
87 void *in_handler_priv; /* additional information for the in_handler */
93 /* IN: from device to host, OUT: from host to device */
94 SCAN_IN = 1, SCAN_OUT = 2, SCAN_IO = 3
97 typedef struct scan_command_s
99 int ir_scan; /* instruction/not data scan */
100 int num_fields; /* number of fields in *fields array */
101 scan_field_t *fields; /* pointer to an array of data scan fields */
102 enum tap_state end_state; /* TAP state in which JTAG commands should finish */
105 typedef struct statemove_command_s
107 enum tap_state end_state; /* TAP state in which JTAG commands should finish */
108 } statemove_command_t;
110 typedef struct pathmove_command_s
112 int num_states; /* number of states in *path */
113 enum tap_state *path; /* states that have to be passed */
114 } pathmove_command_t;
116 typedef struct runtest_command_s
118 int num_cycles; /* number of cycles that should be spent in Run-Test/Idle */
119 enum tap_state end_state; /* TAP state in which JTAG commands should finish */
122 typedef struct reset_command_s
124 int trst; /* trst/srst 0: deassert, 1: assert, -1: don't change */
128 typedef struct end_state_command_s
130 enum tap_state end_state; /* TAP state in which JTAG commands should finish */
131 } end_state_command_t;
133 typedef struct sleep_command_s
135 u32 us; /* number of microseconds to sleep */
138 typedef union jtag_command_container_u
140 scan_command_t *scan;
141 statemove_command_t *statemove;
142 pathmove_command_t *pathmove;
143 runtest_command_t *runtest;
144 reset_command_t *reset;
145 end_state_command_t *end_state;
146 sleep_command_t *sleep;
147 } jtag_command_container_t;
149 enum jtag_command_type
152 JTAG_STATEMOVE = 2, JTAG_RUNTEST = 3,
153 JTAG_RESET = 4, JTAG_END_STATE = 5,
154 JTAG_PATHMOVE = 6, JTAG_SLEEP = 7
157 typedef struct jtag_command_s
159 jtag_command_container_t cmd;
160 enum jtag_command_type type;
161 struct jtag_command_s *next;
164 extern jtag_command_t *jtag_command_queue;
166 typedef struct jtag_device_s
168 int ir_length; /* size of instruction register */
169 u8 *expected; /* Capture-IR expected value */
170 u8 *expected_mask; /* Capture-IR expected mask */
171 u32 idcode; /* device identification code */
172 u8 *cur_instr; /* current instruction */
173 int bypass; /* bypass register selected */
174 struct jtag_device_s *next;
177 extern jtag_device_t *jtag_devices;
178 extern int jtag_num_devices;
179 extern int jtag_ir_scan_size;
183 LINE_OPEN_DRAIN = 0x0,
184 LINE_PUSH_PULL = 0x1,
187 typedef struct jtag_interface_s
191 /* queued command execution
193 int (*execute_queue)(void);
195 /* interface initalization
197 int (*speed)(int speed);
198 int (*register_commands)(struct command_context_s *cmd_ctx);
201 /* returns JTAG maxium speed for KHz. 0=RTCK. The function returns
202 a failure if it can't support the KHz/RTCK.
204 WARNING!!!! if RTCK is *slow* then think carefully about
205 whether you actually want to support this in the driver.
206 Many target scripts are written to handle the absence of RTCK
207 and use a fallback kHz TCK.
209 int (*khz)(int khz, int *jtag_speed);
210 /* returns the KHz for the provided JTAG speed. 0=RTCK. The function returns
211 a failure if it can't support the KHz/RTCK. */
212 int (*speed_div)(int speed, int *khz);
214 /* Read and clear the power dropout flag. Note that a power dropout
215 can be transitionary, easily much less than a ms.
217 So to find out if the power is *currently* on, you must invoke
218 this method twice. Once to clear the power dropout flag and a
219 second time to read the current state.
221 Currently the default implementation is never to detect power dropout.
223 int (*power_dropout)(int *power_dropout);
224 /* Read and clear the srst asserted detection flag.
226 * NB!!!! like power_dropout this does *not* read the current
227 * state. srst assertion is transitionary and *can* be much
230 int (*srst_asserted)(int *srst_asserted);
239 extern char* jtag_event_strings[];
241 extern int jtag_trst;
242 extern int jtag_srst;
244 typedef struct jtag_event_callback_s
246 int (*callback)(enum jtag_event event, void *priv);
248 struct jtag_event_callback_s *next;
249 } jtag_event_callback_t;
251 extern jtag_event_callback_t *jtag_event_callbacks;
253 extern jtag_interface_t *jtag; /* global pointer to configured JTAG interface */
254 extern enum tap_state end_state;
255 extern enum tap_state cur_state;
257 extern int jtag_speed;
258 extern int jtag_speed_post_reset;
263 RESET_HAS_TRST = 0x1,
264 RESET_HAS_SRST = 0x2,
265 RESET_TRST_AND_SRST = 0x3,
266 RESET_SRST_PULLS_TRST = 0x4,
267 RESET_TRST_PULLS_SRST = 0x8,
268 RESET_TRST_OPEN_DRAIN = 0x10,
269 RESET_SRST_PUSH_PULL = 0x20,
272 extern enum reset_types jtag_reset_config;
274 /* initialize interface upon startup. A successful no-op
275 * upon subsequent invocations
277 extern int jtag_interface_init(struct command_context_s *cmd_ctx);
278 /* initialize JTAG chain using only a TLR reset. If init fails,
281 extern int jtag_init(struct command_context_s *cmd_ctx);
282 /* reset, then initialize JTAG chain */
283 extern int jtag_init_reset(struct command_context_s *cmd_ctx);
284 extern int jtag_register_commands(struct command_context_s *cmd_ctx);
286 /* JTAG interface, can be implemented with a software or hardware fifo
288 * TAP_SD and TAP_SI are illegal end states. TAP_SD/SI as end states
289 * can be emulated by using a larger scan.
291 * Code that is relatively insensitive to the path(as long
292 * as it is JTAG compliant) taken through state machine can use
293 * endstate for jtag_add_xxx_scan(). Otherwise the pause state must be
294 * specified as end state and a subsequent jtag_add_pathmove() must
298 extern void jtag_add_ir_scan(int num_fields, scan_field_t *fields, enum tap_state endstate);
299 extern int interface_jtag_add_ir_scan(int num_fields, scan_field_t *fields, enum tap_state endstate);
300 extern void jtag_add_dr_scan(int num_fields, scan_field_t *fields, enum tap_state endstate);
301 extern int interface_jtag_add_dr_scan(int num_fields, scan_field_t *fields, enum tap_state endstate);
302 extern void jtag_add_plain_ir_scan(int num_fields, scan_field_t *fields, enum tap_state endstate);
303 extern int interface_jtag_add_plain_ir_scan(int num_fields, scan_field_t *fields, enum tap_state endstate);
304 extern void jtag_add_plain_dr_scan(int num_fields, scan_field_t *fields, enum tap_state endstate);
305 extern int interface_jtag_add_plain_dr_scan(int num_fields, scan_field_t *fields, enum tap_state endstate);
306 /* run a TAP_TLR reset. End state is TAP_TLR, regardless
309 extern void jtag_add_tlr(void);
310 extern int interface_jtag_add_tlr(void);
311 /* Do not use jtag_add_pathmove() unless you need to, but do use it
314 * DANGER! If the target is dependent upon a particular sequence
315 * of transitions for things to work correctly(e.g. as a workaround
316 * for an errata that contradicts the JTAG standard), then pathmove
317 * must be used, even if some jtag interfaces happen to use the
318 * desired path. Worse, the jtag interface used for testing a
319 * particular implementation, could happen to use the "desired"
320 * path when transitioning to/from end
323 * A list of unambigious single clock state transitions, not
324 * all drivers can support this, but it is required for e.g.
325 * XScale and Xilinx support
327 * Note! TAP_TLR must not be used in the path!
329 * Note that the first on the list must be reachable
330 * via a single transition from the current state.
332 * All drivers are required to implement jtag_add_pathmove().
333 * However, if the pathmove sequence can not be precisely
334 * executed, an interface_jtag_add_pathmove() or jtag_execute_queue()
335 * must return an error. It is legal, but not recommended, that
336 * a driver returns an error in all cases for a pathmove if it
337 * can only implement a few transitions and therefore
338 * a partial implementation of pathmove would have little practical
341 extern void jtag_add_pathmove(int num_states, enum tap_state *path);
342 extern int interface_jtag_add_pathmove(int num_states, enum tap_state *path);
343 /* go to TAP_RTI, if we're not already there and cycle
344 * precisely num_cycles in the TAP_RTI after which move
345 * to the end state, if it is != TAP_RTI
347 * nb! num_cycles can be 0, in which case the fn will navigate
348 * to endstate via TAP_RTI
350 extern void jtag_add_runtest(int num_cycles, enum tap_state endstate);
351 extern int interface_jtag_add_runtest(int num_cycles, enum tap_state endstate);
352 /* A reset of the TAP state machine can be requested.
354 * Whether tms or trst reset is used depends on the capabilities of
355 * the target and jtag interface(reset_config command configures this).
357 * srst can driver a reset of the TAP state machine and vice
360 * Application code may need to examine value of jtag_reset_config
361 * to determine the proper codepath
363 * DANGER! Even though srst drives trst, trst might not be connected to
364 * the interface, and it might actually be *harmful* to assert trst in this case.
366 * This is why combinations such as "reset_config srst_only srst_pulls_trst"
369 * only req_tlr_or_trst and srst can have a transition for a
370 * call as the effects of transitioning both at the "same time"
371 * are undefined, but when srst_pulls_trst or vice versa,
372 * then trst & srst *must* be asserted together.
374 extern void jtag_add_reset(int req_tlr_or_trst, int srst);
375 /* this drives the actual srst and trst pins. srst will always be 0
376 * if jtag_reset_config & RESET_SRST_PULLS_TRST != 0 and ditto for
379 * the higher level jtag_add_reset will invoke jtag_add_tlr() if
382 extern int interface_jtag_add_reset(int trst, int srst);
383 extern void jtag_add_end_state(enum tap_state endstate);
384 extern int interface_jtag_add_end_state(enum tap_state endstate);
385 extern void jtag_add_sleep(u32 us);
386 extern int interface_jtag_add_sleep(u32 us);
391 * For software FIFO implementations, the queued commands can be executed
392 * during this call or earlier. A sw queue might decide to push out
393 * some of the jtag_add_xxx() operations once the queue is "big enough".
395 * This fn will return an error code if any of the prior jtag_add_xxx()
396 * calls caused a failure, e.g. check failure. Note that it does not
397 * matter if the operation was executed *before* jtag_execute_queue(),
398 * jtag_execute_queue() will still return an error code.
400 * All jtag_add_xxx() calls that have in_handler!=NULL will have been
401 * executed when this fn returns, but if what has been queued only
402 * clocks data out, without reading anything back, then JTAG could
403 * be running *after* jtag_execute_queue() returns. The API does
404 * not define a way to flush a hw FIFO that runs *after*
405 * jtag_execute_queue() returns.
407 * jtag_add_xxx() commands can either be executed immediately or
408 * at some time between the jtag_add_xxx() fn call and jtag_execute_queue().
410 extern int jtag_execute_queue(void);
411 /* can be implemented by hw+sw */
412 extern int interface_jtag_execute_queue(void);
413 extern int jtag_power_dropout(int *dropout);
414 extern int jtag_srst_asserted(int *srst_asserted);
417 /* JTAG support functions */
418 extern void jtag_set_check_value(scan_field_t *field, u8 *value, u8 *mask, error_handler_t *in_error_handler);
419 extern enum scan_type jtag_scan_type(scan_command_t *cmd);
420 extern int jtag_scan_size(scan_command_t *cmd);
421 extern int jtag_read_buffer(u8 *buffer, scan_command_t *cmd);
422 extern int jtag_build_buffer(scan_command_t *cmd, u8 **buffer);
423 extern jtag_device_t* jtag_get_device(int num);
424 extern void jtag_sleep(u32 us);
425 extern int jtag_call_event_callbacks(enum jtag_event event);
426 extern int jtag_register_event_callback(int (*callback)(enum jtag_event event, void *priv), void *priv);
428 extern int jtag_verify_capture_ir;
431 * JTAG subsystem uses codes between -100 and -199 */
433 #define ERROR_JTAG_INIT_FAILED (-100)
434 #define ERROR_JTAG_INVALID_INTERFACE (-101)
435 #define ERROR_JTAG_NOT_IMPLEMENTED (-102)
436 #define ERROR_JTAG_TRST_ASSERTED (-103)
437 #define ERROR_JTAG_QUEUE_FAILED (-104)
438 #define ERROR_JTAG_DEVICE_ERROR (-107)
442 /* this allows JTAG devices to implement the entire jtag_xxx() layer in hw/sw */
443 #ifdef HAVE_JTAG_MINIDRIVER_H
444 /* Here a #define MINIDRIVER() and an inline version of hw fifo interface_jtag_add_dr_out can be defined */
445 #include "jtag_minidriver.h"
446 #define MINIDRIVER(a) notused ## a
448 #define MINIDRIVER(a) a
449 /* jtag_add_dr_out() is a faster version of jtag_add_dr_scan()
451 * Current or end_state can not be TAP_TLR. end_state can be -1
453 * num_bits[i] is the number of bits to clock out from value[i] LSB first.
455 * If the device is in bypass, then that is an error condition in
456 * the caller code that is not detected by this fn, whereas jtag_add_dr_scan()
457 * does detect it. Similarly if the device is not in bypass, data must
460 * If anything fails, then jtag_error will be set and jtag_execute() will
461 * return an error. There is no way to determine if there was a failure
462 * during this function call.
464 * Note that this jtag_add_dr_out can be defined as an inline function.
466 extern void interface_jtag_add_dr_out(int device,
470 enum tap_state end_state);
476 static __inline__ void jtag_add_dr_out(int device,
480 enum tap_state end_state)
483 cmd_queue_end_state=end_state;
484 cmd_queue_cur_state=cmd_queue_end_state;
485 interface_jtag_add_dr_out(device, num_fields, num_bits, value, cmd_queue_end_state);