1 /*************************************************************************** 2 * Copyright (C) 2005 by Dominic Rath * 3 * Dominic.Rath@gmx.de * 4 * * 5 * Copyright (C) 2007-2010 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, see <http://www.gnu.org/licenses/>. * 20 ***************************************************************************/ 21 22 #ifndef OPENOCD_JTAG_JTAG_H 23 #define OPENOCD_JTAG_JTAG_H 24 25 #include <helper/binarybuffer.h> 26 #include <helper/log.h> 27 28 #ifndef DEBUG_JTAG_IOZ 29 #define DEBUG_JTAG_IOZ 64 30 #endif 31 32 /*-----</Macros>-------------------------------------------------*/ 33 34 /** 35 * Defines JTAG Test Access Port states. 36 * 37 * These definitions were gleaned from the ARM7TDMI-S Technical 38 * Reference Manual and validated against several other ARM core 39 * technical manuals. 40 * 41 * FIXME some interfaces require specific numbers be used, as they 42 * are handed-off directly to their hardware implementations. 43 * Fix those drivers to map as appropriate ... then pick some 44 * sane set of numbers here (where 0/uninitialized == INVALID). 45 */ 46 typedef enum tap_state { 47 TAP_INVALID = -1, 48 49 #if BUILD_ZY1000 50 /* These are the old numbers. Leave as-is for now... */ 51 TAP_RESET = 0, TAP_IDLE = 8, 52 TAP_DRSELECT = 1, TAP_DRCAPTURE = 2, TAP_DRSHIFT = 3, TAP_DREXIT1 = 4, 53 TAP_DRPAUSE = 5, TAP_DREXIT2 = 6, TAP_DRUPDATE = 7, 54 TAP_IRSELECT = 9, TAP_IRCAPTURE = 10, TAP_IRSHIFT = 11, TAP_IREXIT1 = 12, 55 TAP_IRPAUSE = 13, TAP_IREXIT2 = 14, TAP_IRUPDATE = 15, 56 57 #else 58 /* Proper ARM recommended numbers */ 59 TAP_DREXIT2 = 0x0, 60 TAP_DREXIT1 = 0x1, 61 TAP_DRSHIFT = 0x2, 62 TAP_DRPAUSE = 0x3, 63 TAP_IRSELECT = 0x4, 64 TAP_DRUPDATE = 0x5, 65 TAP_DRCAPTURE = 0x6, 66 TAP_DRSELECT = 0x7, 67 TAP_IREXIT2 = 0x8, 68 TAP_IREXIT1 = 0x9, 69 TAP_IRSHIFT = 0xa, 70 TAP_IRPAUSE = 0xb, 71 TAP_IDLE = 0xc, 72 TAP_IRUPDATE = 0xd, 73 TAP_IRCAPTURE = 0xe, 74 TAP_RESET = 0x0f, 75 76 #endif 77 } tap_state_t; 78 79 /** 80 * Defines arguments for reset functions 81 */ 82 #define SRST_DEASSERT 0 83 #define SRST_ASSERT 1 84 #define TRST_DEASSERT 0 85 #define TRST_ASSERT 1 86 87 /** 88 * Function tap_state_name 89 * Returns a string suitable for display representing the JTAG tap_state 90 */ 91 const char *tap_state_name(tap_state_t state); 92 93 /** Provides user-friendly name lookup of TAP states. */ 94 tap_state_t tap_state_by_name(const char *name); 95 96 /** The current TAP state of the pending JTAG command queue. */ 97 extern tap_state_t cmd_queue_cur_state; 98 99 /** 100 * This structure defines a single scan field in the scan. It provides 101 * fields for the field's width and pointers to scan input and output 102 * values. 103 * 104 * In addition, this structure includes a value and mask that is used by 105 * jtag_add_dr_scan_check() to validate the value that was scanned out. 106 */ 107 struct scan_field { 108 /** The number of bits this field specifies */ 109 int num_bits; 110 /** A pointer to value to be scanned into the device */ 111 const uint8_t *out_value; 112 /** A pointer to a 32-bit memory location for data scanned out */ 113 uint8_t *in_value; 114 115 /** The value used to check the data scanned out. */ 116 uint8_t *check_value; 117 /** The mask to go with check_value */ 118 uint8_t *check_mask; 119 }; 120 121 struct jtag_tap { 122 char *chip; 123 char *tapname; 124 char *dotted_name; 125 int abs_chain_position; 126 /** Is this TAP disabled after JTAG reset? */ 127 bool disabled_after_reset; 128 /** Is this TAP currently enabled? */ 129 bool enabled; 130 int ir_length; /**< size of instruction register */ 131 uint32_t ir_capture_value; 132 uint8_t *expected; /**< Capture-IR expected value */ 133 uint32_t ir_capture_mask; 134 uint8_t *expected_mask; /**< Capture-IR expected mask */ 135 uint32_t idcode; /**< device identification code */ 136 /** not all devices have idcode, 137 * we'll discover this during chain examination */ 138 bool hasidcode; 139 140 /** Array of expected identification codes */ 141 uint32_t *expected_ids; 142 /** Number of expected identification codes */ 143 uint8_t expected_ids_cnt; 144 145 /** Flag saying whether to ignore version field in expected_ids[] */ 146 bool ignore_version; 147 148 /** current instruction */ 149 uint8_t *cur_instr; 150 /** Bypass register selected */ 151 int bypass; 152 153 struct jtag_tap_event_action *event_action; 154 155 struct jtag_tap *next_tap; 156 /* private pointer to support none-jtag specific functions */ 157 void *priv; 158 }; 159 160 void jtag_tap_init(struct jtag_tap *tap); 161 void jtag_tap_free(struct jtag_tap *tap); 162 163 struct jtag_tap *jtag_all_taps(void); 164 const char *jtag_tap_name(const struct jtag_tap *tap); 165 struct jtag_tap *jtag_tap_by_string(const char *dotted_name); 166 struct jtag_tap *jtag_tap_by_jim_obj(Jim_Interp *interp, Jim_Obj *obj); 167 struct jtag_tap *jtag_tap_by_position(unsigned abs_position); 168 struct jtag_tap *jtag_tap_next_enabled(struct jtag_tap *p); 169 unsigned jtag_tap_count_enabled(void); 170 unsigned jtag_tap_count(void); 171 172 /* 173 * - TRST_ASSERTED triggers two sets of callbacks, after operations to 174 * reset the scan chain -- via TMS+TCK signaling, or deasserting the 175 * nTRST signal -- are queued: 176 * 177 * + Callbacks in C code fire first, patching internal state 178 * + Then post-reset event scripts fire ... activating JTAG circuits 179 * via TCK cycles, exiting SWD mode via TMS sequences, etc 180 * 181 * During those callbacks, scan chain contents have not been validated. 182 * JTAG operations that address a specific TAP (primarily DR/IR scans) 183 * must *not* be queued. 184 * 185 * - TAP_EVENT_SETUP is reported after TRST_ASSERTED, and after the scan 186 * chain has been validated. JTAG operations including scans that 187 * target specific TAPs may be performed. 188 * 189 * - TAP_EVENT_ENABLE and TAP_EVENT_DISABLE implement TAP activation and 190 * deactivation outside the core using scripted code that understands 191 * the specific JTAG router type. They might be triggered indirectly 192 * from EVENT_SETUP operations. 193 */ 194 enum jtag_event { 195 JTAG_TRST_ASSERTED, 196 JTAG_TAP_EVENT_SETUP, 197 JTAG_TAP_EVENT_ENABLE, 198 JTAG_TAP_EVENT_DISABLE, 199 }; 200 201 struct jtag_tap_event_action { 202 /** The event for which this action will be triggered. */ 203 enum jtag_event event; 204 /** The interpreter to use for evaluating the @c body. */ 205 Jim_Interp *interp; 206 /** Contains a script to 'eval' when the @c event is triggered. */ 207 Jim_Obj *body; 208 /* next action in linked list */ 209 struct jtag_tap_event_action *next; 210 }; 211 212 /** 213 * Defines the function signature required for JTAG event callback 214 * functions, which are added with jtag_register_event_callback() 215 * and removed jtag_unregister_event_callback(). 216 * @param event The event to handle. 217 * @param priv A pointer to data that was passed to 218 * jtag_register_event_callback(). 219 * @returns Must return ERROR_OK on success, or an error code on failure. 220 * 221 * @todo Change to return void or define a use for its return code. 222 */ 223 typedef int (*jtag_event_handler_t)(enum jtag_event event, void *priv); 224 225 int jtag_register_event_callback(jtag_event_handler_t f, void *x); 226 int jtag_unregister_event_callback(jtag_event_handler_t f, void *x); 227 228 int jtag_call_event_callbacks(enum jtag_event event); 229 230 231 /** @returns The current JTAG speed setting. */ 232 int jtag_get_speed(int *speed); 233 234 /** 235 * Given a @a speed setting, use the interface @c speed_div callback to 236 * adjust the setting. 237 * @param speed The speed setting to convert back to readable KHz. 238 * @returns ERROR_OK if the interface has not been initialized or on success; 239 * otherwise, the error code produced by the @c speed_div callback. 240 */ 241 int jtag_get_speed_readable(int *speed); 242 243 /** Attempt to configure the interface for the specified KHz. */ 244 int jtag_config_khz(unsigned khz); 245 246 /** 247 * Attempt to enable RTCK/RCLK. If that fails, fallback to the 248 * specified frequency. 249 */ 250 int jtag_config_rclk(unsigned fallback_speed_khz); 251 252 /** Retrieves the clock speed of the JTAG interface in KHz. */ 253 unsigned jtag_get_speed_khz(void); 254 255 enum reset_types { 256 RESET_NONE = 0x0, 257 RESET_HAS_TRST = 0x1, 258 RESET_HAS_SRST = 0x2, 259 RESET_TRST_AND_SRST = 0x3, 260 RESET_SRST_PULLS_TRST = 0x4, 261 RESET_TRST_PULLS_SRST = 0x8, 262 RESET_TRST_OPEN_DRAIN = 0x10, 263 RESET_SRST_PUSH_PULL = 0x20, 264 RESET_SRST_NO_GATING = 0x40, 265 RESET_CNCT_UNDER_SRST = 0x80 266 }; 267 268 enum reset_types jtag_get_reset_config(void); 269 void jtag_set_reset_config(enum reset_types type); 270 271 void jtag_set_nsrst_delay(unsigned delay); 272 unsigned jtag_get_nsrst_delay(void); 273 274 void jtag_set_ntrst_delay(unsigned delay); 275 unsigned jtag_get_ntrst_delay(void); 276 277 void jtag_set_nsrst_assert_width(unsigned delay); 278 unsigned jtag_get_nsrst_assert_width(void); 279 280 void jtag_set_ntrst_assert_width(unsigned delay); 281 unsigned jtag_get_ntrst_assert_width(void); 282 283 /** @returns The current state of TRST. */ 284 int jtag_get_trst(void); 285 /** @returns The current state of SRST. */ 286 int jtag_get_srst(void); 287 288 /** Enable or disable data scan verification checking. */ 289 void jtag_set_verify(bool enable); 290 /** @returns True if data scan verification will be performed. */ 291 bool jtag_will_verify(void); 292 293 /** Enable or disable verification of IR scan checking. */ 294 void jtag_set_verify_capture_ir(bool enable); 295 /** @returns True if IR scan verification will be performed. */ 296 bool jtag_will_verify_capture_ir(void); 297 298 /** Initialize debug adapter upon startup. */ 299 int adapter_init(struct command_context *cmd_ctx); 300 301 /** Shutdown the debug adapter upon program exit. */ 302 int adapter_quit(void); 303 304 /** Set ms to sleep after jtag_execute_queue() flushes queue. Debug purposes. */ 305 void jtag_set_flush_queue_sleep(int ms); 306 307 /** 308 * Initialize JTAG chain using only a RESET reset. If init fails, 309 * try reset + init. 310 */ 311 int jtag_init(struct command_context *cmd_ctx); 312 313 /** reset, then initialize JTAG chain */ 314 int jtag_init_reset(struct command_context *cmd_ctx); 315 int jtag_register_commands(struct command_context *cmd_ctx); 316 int jtag_init_inner(struct command_context *cmd_ctx); 317 318 /** 319 * @file 320 * The JTAG interface can be implemented with a software or hardware fifo. 321 * 322 * TAP_DRSHIFT and TAP_IRSHIFT are illegal end states; however, 323 * TAP_DRSHIFT/IRSHIFT can be emulated as end states, by using longer 324 * scans. 325 * 326 * Code that is relatively insensitive to the path taken through state 327 * machine (as long as it is JTAG compliant) can use @a endstate for 328 * jtag_add_xxx_scan(). Otherwise, the pause state must be specified as 329 * end state and a subsequent jtag_add_pathmove() must be issued. 330 */ 331 332 /** 333 * Generate an IR SCAN with a list of scan fields with one entry for 334 * each enabled TAP. 335 * 336 * If the input field list contains an instruction value for a TAP then 337 * that is used otherwise the TAP is set to bypass. 338 * 339 * TAPs for which no fields are passed are marked as bypassed for 340 * subsequent DR SCANs. 341 * 342 */ 343 void jtag_add_ir_scan(struct jtag_tap *tap, 344 struct scan_field *fields, tap_state_t endstate); 345 /** 346 * The same as jtag_add_ir_scan except no verification is performed out 347 * the output values. 348 */ 349 void jtag_add_ir_scan_noverify(struct jtag_tap *tap, 350 const struct scan_field *fields, tap_state_t state); 351 /** 352 * Scan out the bits in ir scan mode. 353 * 354 * If in_bits == NULL, discard incoming bits. 355 */ 356 void jtag_add_plain_ir_scan(int num_bits, const uint8_t *out_bits, uint8_t *in_bits, 357 tap_state_t endstate); 358 359 /** 360 * Generate a DR SCAN using the fields passed to the function. 361 * For connected TAPs, the function checks in_fields and uses fields 362 * specified there. For bypassed TAPs, the function generates a dummy 363 * 1-bit field. The bypass status of TAPs is set by jtag_add_ir_scan(). 364 */ 365 void jtag_add_dr_scan(struct jtag_tap *tap, int num_fields, 366 const struct scan_field *fields, tap_state_t endstate); 367 /** A version of jtag_add_dr_scan() that uses the check_value/mask fields */ 368 void jtag_add_dr_scan_check(struct jtag_tap *tap, int num_fields, 369 struct scan_field *fields, tap_state_t endstate); 370 /** 371 * Scan out the bits in ir scan mode. 372 * 373 * If in_bits == NULL, discard incoming bits. 374 */ 375 void jtag_add_plain_dr_scan(int num_bits, 376 const uint8_t *out_bits, uint8_t *in_bits, tap_state_t endstate); 377 378 /** 379 * Defines the type of data passed to the jtag_callback_t interface. 380 * The underlying type must allow storing an @c int or pointer type. 381 */ 382 typedef intptr_t jtag_callback_data_t; 383 384 /** 385 * Defines a simple JTAG callback that can allow conversions on data 386 * scanned in from an interface. 387 * 388 * This callback should only be used for conversion that cannot fail. 389 * For conversion types or checks that can fail, use the more complete 390 * variant: jtag_callback_t. 391 */ 392 typedef void (*jtag_callback1_t)(jtag_callback_data_t data0); 393 394 /** A simpler version of jtag_add_callback4(). */ 395 void jtag_add_callback(jtag_callback1_t f, jtag_callback_data_t data0); 396 397 398 /** 399 * Defines the interface of the JTAG callback mechanism. Such 400 * callbacks can be executed once the queue has been flushed. 401 * 402 * The JTAG queue can be executed synchronously or asynchronously. 403 * Typically for USB, the queue is executed asynchronously. For 404 * low-latency interfaces, the queue may be executed synchronously. 405 * 406 * The callback mechanism is very general and does not make many 407 * assumptions about what the callback does or what its arguments are. 408 * These callbacks are typically executed *after* the *entire* JTAG 409 * queue has been executed for e.g. USB interfaces, and they are 410 * guaranteed to be invoked in the order that they were queued. 411 * 412 * If the execution of the queue fails before the callbacks, then -- 413 * depending on driver implementation -- the callbacks may or may not be 414 * invoked. 415 * 416 * @todo Make that behavior consistent. 417 * 418 * @param data0 Typically used to point to the data to operate on. 419 * Frequently this will be the data clocked in during a shift operation. 420 * @param data1 An integer big enough to use as an @c int or a pointer. 421 * @param data2 An integer big enough to use as an @c int or a pointer. 422 * @param data3 An integer big enough to use as an @c int or a pointer. 423 * @returns an error code 424 */ 425 typedef int (*jtag_callback_t)(jtag_callback_data_t data0, 426 jtag_callback_data_t data1, 427 jtag_callback_data_t data2, 428 jtag_callback_data_t data3); 429 430 /** 431 * Run a TAP_RESET reset where the end state is TAP_RESET, 432 * regardless of the start state. 433 */ 434 void jtag_add_tlr(void); 435 436 /** 437 * Application code *must* assume that interfaces will 438 * implement transitions between states with different 439 * paths and path lengths through the state diagram. The 440 * path will vary across interface and also across versions 441 * of the same interface over time. Even if the OpenOCD code 442 * is unchanged, the actual path taken may vary over time 443 * and versions of interface firmware or PCB revisions. 444 * 445 * Use jtag_add_pathmove() when specific transition sequences 446 * are required. 447 * 448 * Do not use jtag_add_pathmove() unless you need to, but do use it 449 * if you have to. 450 * 451 * DANGER! If the target is dependent upon a particular sequence 452 * of transitions for things to work correctly(e.g. as a workaround 453 * for an errata that contradicts the JTAG standard), then pathmove 454 * must be used, even if some jtag interfaces happen to use the 455 * desired path. Worse, the jtag interface used for testing a 456 * particular implementation, could happen to use the "desired" 457 * path when transitioning to/from end 458 * state. 459 * 460 * A list of unambiguous single clock state transitions, not 461 * all drivers can support this, but it is required for e.g. 462 * XScale and Xilinx support 463 * 464 * Note! TAP_RESET must not be used in the path! 465 * 466 * Note that the first on the list must be reachable 467 * via a single transition from the current state. 468 * 469 * All drivers are required to implement jtag_add_pathmove(). 470 * However, if the pathmove sequence can not be precisely 471 * executed, an interface_jtag_add_pathmove() or jtag_execute_queue() 472 * must return an error. It is legal, but not recommended, that 473 * a driver returns an error in all cases for a pathmove if it 474 * can only implement a few transitions and therefore 475 * a partial implementation of pathmove would have little practical 476 * application. 477 * 478 * If an error occurs, jtag_error will contain one of these error codes: 479 * - ERROR_JTAG_NOT_STABLE_STATE -- The final state was not stable. 480 * - ERROR_JTAG_STATE_INVALID -- The path passed through TAP_RESET. 481 * - ERROR_JTAG_TRANSITION_INVALID -- The path includes invalid 482 * state transitions. 483 */ 484 void jtag_add_pathmove(int num_states, const tap_state_t *path); 485 486 /** 487 * jtag_add_statemove() moves from the current state to @a goal_state. 488 * 489 * @param goal_state The final TAP state. 490 * @return ERROR_OK on success, or an error code on failure. 491 * 492 * Moves from the current state to the goal \a state. 493 * Both states must be stable. 494 */ 495 int jtag_add_statemove(tap_state_t goal_state); 496 497 /** 498 * Goes to TAP_IDLE (if we're not already there), cycle 499 * precisely num_cycles in the TAP_IDLE state, after which move 500 * to @a endstate (unless it is also TAP_IDLE). 501 * 502 * @param num_cycles Number of cycles in TAP_IDLE state. This argument 503 * may be 0, in which case this routine will navigate to @a endstate 504 * via TAP_IDLE. 505 * @param endstate The final state. 506 */ 507 void jtag_add_runtest(int num_cycles, tap_state_t endstate); 508 509 /** 510 * A reset of the TAP state machine can be requested. 511 * 512 * Whether tms or trst reset is used depends on the capabilities of 513 * the target and jtag interface(reset_config command configures this). 514 * 515 * srst can driver a reset of the TAP state machine and vice 516 * versa 517 * 518 * Application code may need to examine value of jtag_reset_config 519 * to determine the proper codepath 520 * 521 * DANGER! Even though srst drives trst, trst might not be connected to 522 * the interface, and it might actually be *harmful* to assert trst in this case. 523 * 524 * This is why combinations such as "reset_config srst_only srst_pulls_trst" 525 * are supported. 526 * 527 * only req_tlr_or_trst and srst can have a transition for a 528 * call as the effects of transitioning both at the "same time" 529 * are undefined, but when srst_pulls_trst or vice versa, 530 * then trst & srst *must* be asserted together. 531 */ 532 void jtag_add_reset(int req_tlr_or_trst, int srst); 533 534 void jtag_add_sleep(uint32_t us); 535 536 int jtag_add_tms_seq(unsigned nbits, const uint8_t *seq, enum tap_state t); 537 538 /** 539 * Function jtag_add_clocks 540 * first checks that the state in which the clocks are to be issued is 541 * stable, then queues up num_cycles clocks for transmission. 542 */ 543 void jtag_add_clocks(int num_cycles); 544 545 /** 546 * For software FIFO implementations, the queued commands can be executed 547 * during this call or earlier. A sw queue might decide to push out 548 * some of the jtag_add_xxx() operations once the queue is "big enough". 549 * 550 * This fn will return an error code if any of the prior jtag_add_xxx() 551 * calls caused a failure, e.g. check failure. Note that it does not 552 * matter if the operation was executed *before* jtag_execute_queue(), 553 * jtag_execute_queue() will still return an error code. 554 * 555 * All jtag_add_xxx() calls that have in_handler != NULL will have been 556 * executed when this fn returns, but if what has been queued only 557 * clocks data out, without reading anything back, then JTAG could 558 * be running *after* jtag_execute_queue() returns. The API does 559 * not define a way to flush a hw FIFO that runs *after* 560 * jtag_execute_queue() returns. 561 * 562 * jtag_add_xxx() commands can either be executed immediately or 563 * at some time between the jtag_add_xxx() fn call and jtag_execute_queue(). 564 */ 565 int jtag_execute_queue(void); 566 567 /** same as jtag_execute_queue() but does not clear the error flag */ 568 void jtag_execute_queue_noclear(void); 569 570 /** @returns the number of times the scan queue has been flushed */ 571 int jtag_get_flush_queue_count(void); 572 573 /** Report Tcl event to all TAPs */ 574 void jtag_notify_event(enum jtag_event); 575 576 /* can be implemented by hw + sw */ 577 int jtag_power_dropout(int *dropout); 578 int jtag_srst_asserted(int *srst_asserted); 579 580 /* JTAG support functions */ 581 582 /** 583 * Execute jtag queue and check value with an optional mask. 584 * @param field Pointer to scan field. 585 * @param value Pointer to scan value. 586 * @param mask Pointer to scan mask; may be NULL. 587 * @returns Nothing, but calls jtag_set_error() on any error. 588 */ 589 void jtag_check_value_mask(struct scan_field *field, uint8_t *value, uint8_t *mask); 590 591 void jtag_sleep(uint32_t us); 592 593 /* 594 * The JTAG subsystem defines a number of error codes, 595 * using codes between -100 and -199. 596 */ 597 #define ERROR_JTAG_INIT_FAILED (-100) 598 #define ERROR_JTAG_INVALID_INTERFACE (-101) 599 #define ERROR_JTAG_NOT_IMPLEMENTED (-102) 600 #define ERROR_JTAG_TRST_ASSERTED (-103) 601 #define ERROR_JTAG_QUEUE_FAILED (-104) 602 #define ERROR_JTAG_NOT_STABLE_STATE (-105) 603 #define ERROR_JTAG_DEVICE_ERROR (-107) 604 #define ERROR_JTAG_STATE_INVALID (-108) 605 #define ERROR_JTAG_TRANSITION_INVALID (-109) 606 #define ERROR_JTAG_INIT_SOFT_FAIL (-110) 607 608 /** 609 * Set the current JTAG core execution error, unless one was set 610 * by a previous call previously. Driver or application code must 611 * use jtag_error_clear to reset jtag_error once this routine has been 612 * called with a non-zero error code. 613 */ 614 void jtag_set_error(int error); 615 /** 616 * Resets jtag_error to ERROR_OK, returning its previous value. 617 * @returns The previous value of @c jtag_error. 618 */ 619 int jtag_error_clear(void); 620 621 /** 622 * Return true if it's safe for a background polling task to access the 623 * JTAG scan chain. Polling may be explicitly disallowed, and is also 624 * unsafe while nTRST is active or the JTAG clock is gated off. 625 */ 626 bool is_jtag_poll_safe(void); 627 628 /** 629 * Return flag reporting whether JTAG polling is disallowed. 630 */ 631 bool jtag_poll_get_enabled(void); 632 633 /** 634 * Assign flag reporting whether JTAG polling is disallowed. 635 */ 636 void jtag_poll_set_enabled(bool value); 637 638 639 /* The minidriver may have inline versions of some of the low 640 * level APIs that are used in inner loops. */ 641 #include <jtag/minidriver.h> 642 643 int jim_jtag_newtap(Jim_Interp *interp, int argc, Jim_Obj *const *argv); 644 645 #endif /* OPENOCD_JTAG_JTAG_H */ 646