git.sur5r.net Git - openocd/blob - src/target/adi_v5_jtag.c

   1 /***************************************************************************
   2  *   Copyright (C) 2006 by Magnus Lundin
   3  *   lundin@mlu.mine.nu
   4  *
   5  *   Copyright (C) 2008 by Spencer Oliver
   6  *   spen@spen-soft.co.uk
   7  *
   8  *   Copyright (C) 2009 by Oyvind Harboe
   9  *   oyvind.harboe@zylin.com
  10  *
  11  *   Copyright (C) 2009-2010 by David Brownell
  12  *
  13  *   This program is free software; you can redistribute it and/or modify
  14  *   it under the terms of the GNU General Public License as published by
  15  *   the Free Software Foundation; either version 2 of the License, or
  16  *   (at your option) any later version.
  17  *
  18  *   This program is distributed in the hope that it will be useful,
  19  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  *   GNU General Public License for more details.
  22  *
  23  *   You should have received a copy of the GNU General Public License
  24  *   along with this program.  If not, see <http://www.gnu.org/licenses/>.
  25  ***************************************************************************/
  26
  27 /**
  28  * @file
  29  * This file implements JTAG transport support for cores implementing
  30  the ARM Debug Interface version 5 (ADIv5).
  31  */
  32
  33 #ifdef HAVE_CONFIG_H
  34 #include "config.h"
  35 #endif
  36
  37 #include "arm.h"
  38 #include "arm_adi_v5.h"
  39 #include <helper/time_support.h>
  40 #include <helper/list.h>
  41
  42 /*#define DEBUG_WAIT*/
  43
  44 /* JTAG instructions/registers for JTAG-DP and SWJ-DP */
  45 #define JTAG_DP_ABORT           0x8
  46 #define JTAG_DP_DPACC           0xA
  47 #define JTAG_DP_APACC           0xB
  48 #define JTAG_DP_IDCODE          0xE
  49
  50 /* three-bit ACK values for DPACC and APACC reads */
  51 #define JTAG_ACK_OK_FAULT       0x2
  52 #define JTAG_ACK_WAIT           0x1
  53
  54 static int jtag_ap_q_abort(struct adiv5_dap *dap, uint8_t *ack);
  55
  56 #ifdef DEBUG_WAIT
  57 static const char *dap_reg_name(int instr, int reg_addr)
  58 {
  59         char *reg_name = "UNK";
  60
  61         if (instr == JTAG_DP_DPACC) {
  62                 switch (reg_addr) {
  63                 case DP_ABORT:
  64                         reg_name =  "ABORT";
  65                         break;
  66                 case DP_CTRL_STAT:
  67                         reg_name =  "CTRL/STAT";
  68                         break;
  69                 case DP_SELECT:
  70                         reg_name = "SELECT";
  71                         break;
  72                 case DP_RDBUFF:
  73                         reg_name =  "RDBUFF";
  74                         break;
  75                 case DP_WCR:
  76                         reg_name =  "WCR";
  77                         break;
  78                 default:
  79                         reg_name = "UNK";
  80                         break;
  81                 }
  82         }
  83
  84         if (instr == JTAG_DP_APACC) {
  85                 switch (reg_addr) {
  86                 case MEM_AP_REG_CSW:
  87                         reg_name = "CSW";
  88                         break;
  89                 case MEM_AP_REG_TAR:
  90                         reg_name = "TAR";
  91                         break;
  92                 case MEM_AP_REG_DRW:
  93                         reg_name = "DRW";
  94                         break;
  95                 case MEM_AP_REG_BD0:
  96                         reg_name = "BD0";
  97                         break;
  98                 case MEM_AP_REG_BD1:
  99                         reg_name = "BD1";
 100                         break;
 101                 case MEM_AP_REG_BD2:
 102                         reg_name = "BD2";
 103                         break;
 104                 case MEM_AP_REG_BD3:
 105                         reg_name = "BD3";
 106                         break;
 107                 case MEM_AP_REG_CFG:
 108                         reg_name = "CFG";
 109                         break;
 110                 case MEM_AP_REG_BASE:
 111                         reg_name = "BASE";
 112                         break;
 113                 case AP_REG_IDR:
 114                         reg_name = "IDR";
 115                         break;
 116                 default:
 117                         reg_name = "UNK";
 118                         break;
 119                 }
 120         }
 121
 122         return reg_name;
 123 }
 124 #endif
 125
 126 struct dap_cmd {
 127         struct list_head lh;
 128         uint8_t instr;
 129         uint8_t reg_addr;
 130         uint8_t RnW;
 131         uint8_t *invalue;
 132         uint8_t ack;
 133         uint32_t memaccess_tck;
 134         uint32_t dp_select;
 135
 136         struct scan_field fields[2];
 137         uint8_t out_addr_buf;
 138         uint8_t invalue_buf[4];
 139         uint8_t outvalue_buf[4];
 140 };
 141
 142 static void log_dap_cmd(const char *header, struct dap_cmd *el)
 143 {
 144 #ifdef DEBUG_WAIT
 145         LOG_DEBUG("%s: %2s %6s %5s 0x%08x 0x%08x %2s", header,
 146                 el->instr == JTAG_DP_APACC ? "AP" : "DP",
 147                 dap_reg_name(el->instr, el->reg_addr),
 148                 el->RnW == DPAP_READ ? "READ" : "WRITE",
 149                 buf_get_u32(el->outvalue_buf, 0, 32),
 150                 buf_get_u32(el->invalue, 0, 32),
 151                 el->ack == JTAG_ACK_OK_FAULT ? "OK" :
 152                         (el->ack == JTAG_ACK_WAIT ? "WAIT" : "INVAL"));
 153 #endif
 154 }
 155
 156 static struct dap_cmd *dap_cmd_new(uint8_t instr,
 157                 uint8_t reg_addr, uint8_t RnW,
 158                 uint8_t *outvalue, uint8_t *invalue,
 159                 uint32_t memaccess_tck)
 160 {
 161         struct dap_cmd *cmd;
 162
 163         cmd = (struct dap_cmd *)calloc(1, sizeof(struct dap_cmd));
 164         if (cmd != NULL) {
 165                 INIT_LIST_HEAD(&cmd->lh);
 166                 cmd->instr = instr;
 167                 cmd->reg_addr = reg_addr;
 168                 cmd->RnW = RnW;
 169                 if (outvalue != NULL)
 170                         memcpy(cmd->outvalue_buf, outvalue, 4);
 171                 cmd->invalue = (invalue != NULL) ? invalue : cmd->invalue_buf;
 172                 cmd->memaccess_tck = memaccess_tck;
 173         }
 174
 175         return cmd;
 176 }
 177
 178 static void flush_journal(struct list_head *lh)
 179 {
 180         struct dap_cmd *el, *tmp;
 181
 182         list_for_each_entry_safe(el, tmp, lh, lh) {
 183                 list_del(&el->lh);
 184                 free(el);
 185         }
 186 }
 187
 188 /***************************************************************************
 189  *
 190  * DPACC and APACC scanchain access through JTAG-DP (or SWJ-DP)
 191  *
 192 ***************************************************************************/
 193
 194 static int adi_jtag_dp_scan_cmd(struct adiv5_dap *dap, struct dap_cmd *cmd, uint8_t *ack)
 195 {
 196         struct jtag_tap *tap = dap->tap;
 197         int retval;
 198
 199         retval = arm_jtag_set_instr(tap, cmd->instr, NULL, TAP_IDLE);
 200         if (retval != ERROR_OK)
 201                 return retval;
 202
 203         /* Scan out a read or write operation using some DP or AP register.
 204          * For APACC access with any sticky error flag set, this is discarded.
 205          */
 206         cmd->fields[0].num_bits = 3;
 207         buf_set_u32(&cmd->out_addr_buf, 0, 3, ((cmd->reg_addr >> 1) & 0x6) | (cmd->RnW & 0x1));
 208         cmd->fields[0].out_value = &cmd->out_addr_buf;
 209         cmd->fields[0].in_value = (ack != NULL) ? ack : &cmd->ack;
 210
 211         /* NOTE: if we receive JTAG_ACK_WAIT, the previous operation did not
 212          * complete; data we write is discarded, data we read is unpredictable.
 213          * When overrun detect is active, STICKYORUN is set.
 214          */
 215
 216         cmd->fields[1].num_bits = 32;
 217         cmd->fields[1].out_value = cmd->outvalue_buf;
 218         cmd->fields[1].in_value = cmd->invalue;
 219
 220         jtag_add_dr_scan(tap, 2, cmd->fields, TAP_IDLE);
 221
 222         /* Add specified number of tck clocks after starting memory bus
 223          * access, giving the hardware time to complete the access.
 224          * They provide more time for the (MEM) AP to complete the read ...
 225          * See "Minimum Response Time" for JTAG-DP, in the ADIv5 spec.
 226          */
 227         if (cmd->instr == JTAG_DP_APACC) {
 228                 if (((cmd->reg_addr == MEM_AP_REG_DRW)
 229                         || ((cmd->reg_addr & 0xF0) == MEM_AP_REG_BD0))
 230                         && (cmd->memaccess_tck != 0))
 231                         jtag_add_runtest(cmd->memaccess_tck, TAP_IDLE);
 232         }
 233
 234         return ERROR_OK;
 235 }
 236
 237 static int adi_jtag_dp_scan_cmd_sync(struct adiv5_dap *dap, struct dap_cmd *cmd, uint8_t *ack)
 238 {
 239         int retval;
 240
 241         retval = adi_jtag_dp_scan_cmd(dap, cmd, ack);
 242         if (retval != ERROR_OK)
 243                 return retval;
 244
 245         return jtag_execute_queue();
 246 }
 247
 248 /**
 249  * Scan DPACC or APACC using target ordered uint8_t buffers.  No endianness
 250  * conversions are performed.  See section 4.4.3 of the ADIv5 spec, which
 251  * discusses operations which access these registers.
 252  *
 253  * Note that only one scan is performed.  If RnW is set, a separate scan
 254  * will be needed to collect the data which was read; the "invalue" collects
 255  * the posted result of a preceding operation, not the current one.
 256  *
 257  * @param dap the DAP
 258  * @param instr JTAG_DP_APACC (AP access) or JTAG_DP_DPACC (DP access)
 259  * @param reg_addr two significant bits; A[3:2]; for APACC access, the
 260  *      SELECT register has more addressing bits.
 261  * @param RnW false iff outvalue will be written to the DP or AP
 262  * @param outvalue points to a 32-bit (little-endian) integer
 263  * @param invalue NULL, or points to a 32-bit (little-endian) integer
 264  * @param ack points to where the three bit JTAG_ACK_* code will be stored
 265  * @param memaccess_tck number of idle cycles to add after AP access
 266  */
 267
 268 static int adi_jtag_dp_scan(struct adiv5_dap *dap,
 269                 uint8_t instr, uint8_t reg_addr, uint8_t RnW,
 270                 uint8_t *outvalue, uint8_t *invalue,
 271                 uint32_t memaccess_tck, uint8_t *ack)
 272 {
 273         struct dap_cmd *cmd;
 274         int retval;
 275
 276         cmd = dap_cmd_new(instr, reg_addr, RnW, outvalue, invalue, memaccess_tck);
 277         if (cmd != NULL)
 278                 cmd->dp_select = dap->select;
 279         else
 280                 return ERROR_JTAG_DEVICE_ERROR;
 281
 282         retval = adi_jtag_dp_scan_cmd(dap, cmd, ack);
 283         if (retval == ERROR_OK)
 284                 list_add_tail(&cmd->lh, &dap->cmd_journal);
 285
 286         return retval;
 287 }
 288
 289 /**
 290  * Scan DPACC or APACC out and in from host ordered uint32_t buffers.
 291  * This is exactly like adi_jtag_dp_scan(), except that endianness
 292  * conversions are performed (so the types of invalue and outvalue
 293  * must be different).
 294  */
 295 static int adi_jtag_dp_scan_u32(struct adiv5_dap *dap,
 296                 uint8_t instr, uint8_t reg_addr, uint8_t RnW,
 297                 uint32_t outvalue, uint32_t *invalue,
 298                 uint32_t memaccess_tck, uint8_t *ack)
 299 {
 300         uint8_t out_value_buf[4];
 301         int retval;
 302
 303         buf_set_u32(out_value_buf, 0, 32, outvalue);
 304
 305         retval = adi_jtag_dp_scan(dap, instr, reg_addr, RnW,
 306                         out_value_buf, (uint8_t *)invalue, memaccess_tck, ack);
 307         if (retval != ERROR_OK)
 308                 return retval;
 309
 310         if (invalue)
 311                 jtag_add_callback(arm_le_to_h_u32,
 312                                 (jtag_callback_data_t) invalue);
 313
 314         return retval;
 315 }
 316
 317 static int adi_jtag_finish_read(struct adiv5_dap *dap)
 318 {
 319         int retval = ERROR_OK;
 320
 321         if (dap->last_read != NULL) {
 322                 retval = adi_jtag_dp_scan_u32(dap, JTAG_DP_DPACC,
 323                                 DP_RDBUFF, DPAP_READ, 0, dap->last_read, 0, NULL);
 324                 dap->last_read = NULL;
 325         }
 326
 327         return retval;
 328 }
 329
 330 static int adi_jtag_scan_inout_check_u32(struct adiv5_dap *dap,
 331                 uint8_t instr, uint8_t reg_addr, uint8_t RnW,
 332                 uint32_t outvalue, uint32_t *invalue, uint32_t memaccess_tck)
 333 {
 334         int retval;
 335
 336         /* Issue the read or write */
 337         retval = adi_jtag_dp_scan_u32(dap, instr, reg_addr,
 338                         RnW, outvalue, NULL, memaccess_tck, NULL);
 339         if (retval != ERROR_OK)
 340                 return retval;
 341
 342         /* For reads,  collect posted value; RDBUFF has no other effect.
 343          * Assumes read gets acked with OK/FAULT, and CTRL_STAT says "OK".
 344          */
 345         if ((RnW == DPAP_READ) && (invalue != NULL)) {
 346                 retval = adi_jtag_dp_scan_u32(dap, JTAG_DP_DPACC,
 347                                 DP_RDBUFF, DPAP_READ, 0, invalue, 0, NULL);
 348                 if (retval != ERROR_OK)
 349                         return retval;
 350         }
 351
 352         return jtag_execute_queue();
 353 }
 354
 355 static int jtagdp_overrun_check(struct adiv5_dap *dap)
 356 {
 357         int retval;
 358         struct dap_cmd *el, *tmp, *prev = NULL;
 359         int found_wait = 0;
 360         int64_t time_now;
 361         LIST_HEAD(replay_list);
 362
 363         /* make sure all queued transactions are complete */
 364         retval = jtag_execute_queue();
 365         if (retval != ERROR_OK)
 366                 goto done;
 367
 368         /* skip all completed transactions up to the first WAIT */
 369         list_for_each_entry(el, &dap->cmd_journal, lh) {
 370                 if (el->ack == JTAG_ACK_OK_FAULT) {
 371                         log_dap_cmd("LOG", el);
 372                 } else if (el->ack == JTAG_ACK_WAIT) {
 373                         found_wait = 1;
 374                         break;
 375                 } else {
 376                         LOG_ERROR("Invalid ACK (%1x) in DAP response", el->ack);
 377                         log_dap_cmd("ERR", el);
 378                         retval = ERROR_JTAG_DEVICE_ERROR;
 379                         goto done;
 380                 }
 381         }
 382
 383         /*
 384          * If we found a stalled transaction and a previous transaction
 385          * exists, check if it's a READ access.
 386          */
 387         if (found_wait && el != list_first_entry(&dap->cmd_journal, struct dap_cmd, lh)) {
 388                 prev = list_entry(el->lh.prev, struct dap_cmd, lh);
 389                 if (prev->RnW == DPAP_READ) {
 390                         log_dap_cmd("PND", prev);
 391                         /* search for the next OK transaction, it contains
 392                          * the result of the previous READ */
 393                         tmp = el;
 394                         list_for_each_entry_from(tmp, &dap->cmd_journal, lh) {
 395                                 if (tmp->ack == JTAG_ACK_OK_FAULT) {
 396                                         /* recover the read value */
 397                                         log_dap_cmd("FND", tmp);
 398                                         if (el->invalue != el->invalue_buf) {
 399                                                 uint32_t invalue = le_to_h_u32(tmp->invalue);
 400                                                 memcpy(el->invalue, &invalue, sizeof(uint32_t));
 401                                         }
 402                                         prev = NULL;
 403                                         break;
 404                                 }
 405                         }
 406
 407                         if (prev != NULL) {
 408                                 log_dap_cmd("LST", el);
 409
 410                                 /*
 411                                 * At this point we're sure that no previous
 412                                 * transaction completed and the DAP/AP is still
 413                                 * in busy state. We know that the next "OK" scan
 414                                 * will return the READ result we need to recover.
 415                                 * To complete the READ, we just keep polling RDBUFF
 416                                 * until the WAIT condition clears
 417                                 */
 418                                 tmp = dap_cmd_new(JTAG_DP_DPACC,
 419                                                 DP_RDBUFF, DPAP_READ, NULL, NULL, 0);
 420                                 if (tmp == NULL) {
 421                                         retval = ERROR_JTAG_DEVICE_ERROR;
 422                                         goto done;
 423                                 }
 424                                 /* synchronously retry the command until it succeeds */
 425                                 time_now = timeval_ms();
 426                                 do {
 427                                         retval = adi_jtag_dp_scan_cmd_sync(dap, tmp, NULL);
 428                                         if (retval != ERROR_OK)
 429                                                 break;
 430                                         if (tmp->ack == JTAG_ACK_OK_FAULT) {
 431                                                 log_dap_cmd("FND", tmp);
 432                                                 if (el->invalue != el->invalue_buf) {
 433                                                         uint32_t invalue = le_to_h_u32(tmp->invalue);
 434                                                         memcpy(el->invalue, &invalue, sizeof(uint32_t));
 435                                                 }
 436                                                 break;
 437                                         }
 438                                         if (tmp->ack != JTAG_ACK_WAIT) {
 439                                                 LOG_ERROR("Invalid ACK (%1x) in DAP response", tmp->ack);
 440                                                 log_dap_cmd("ERR", tmp);
 441                                                 retval = ERROR_JTAG_DEVICE_ERROR;
 442                                                 break;
 443                                         }
 444
 445                                 } while (timeval_ms() - time_now < 1000);
 446
 447                                 if (retval == ERROR_OK) {
 448                                         /* timeout happened */
 449                                         if (tmp->ack != JTAG_ACK_OK_FAULT) {
 450                                                 LOG_ERROR("Timeout during WAIT recovery");
 451                                                 jtag_ap_q_abort(dap, NULL);
 452                                                 retval = ERROR_JTAG_DEVICE_ERROR;
 453                                         }
 454                                 }
 455
 456                                 /* we're done with this command, release it */
 457                                 free(tmp);
 458
 459                                 if (retval != ERROR_OK)
 460                                         goto done;
 461
 462                         }
 463                         /* make el->invalue point to the default invalue
 464                         * so that we can safely retry it without clobbering
 465                         * the result we just recovered */
 466                         el->invalue = el->invalue_buf;
 467                 }
 468         }
 469
 470         /* move all remaining transactions over to the replay list */
 471         list_for_each_entry_safe_from(el, tmp, &dap->cmd_journal, lh) {
 472                 log_dap_cmd("REP", el);
 473                 list_move_tail(&el->lh, &replay_list);
 474         }
 475
 476         /* we're done with the journal, flush it */
 477         flush_journal(&dap->cmd_journal);
 478
 479         /* check for overrun condition in the last batch of transactions */
 480         if (found_wait) {
 481                 LOG_INFO("DAP transaction stalled (WAIT) - slowing down");
 482                 /* clear the sticky overrun condition */
 483                 retval = adi_jtag_scan_inout_check_u32(dap, JTAG_DP_DPACC,
 484                                 DP_CTRL_STAT, DPAP_WRITE,
 485                                 dap->dp_ctrl_stat | SSTICKYORUN, NULL, 0);
 486                 if (retval != ERROR_OK)
 487                         goto done;
 488
 489                 /* restore SELECT register first */
 490                 if (!list_empty(&replay_list)) {
 491                         el = list_first_entry(&replay_list, struct dap_cmd, lh);
 492                         tmp = dap_cmd_new(JTAG_DP_DPACC,
 493                                           DP_SELECT, DPAP_WRITE, (uint8_t *)&el->dp_select, NULL, 0);
 494                         if (tmp == NULL) {
 495                                 retval = ERROR_JTAG_DEVICE_ERROR;
 496                                 goto done;
 497                         }
 498                         list_add(&tmp->lh, &replay_list);
 499
 500                         dap->select = DP_SELECT_INVALID;
 501                 }
 502
 503                 list_for_each_entry_safe(el, tmp, &replay_list, lh) {
 504                         time_now = timeval_ms();
 505                         do {
 506                                 retval = adi_jtag_dp_scan_cmd_sync(dap, el, NULL);
 507                                 if (retval != ERROR_OK)
 508                                         break;
 509                                 log_dap_cmd("REC", el);
 510                                 if (el->ack == JTAG_ACK_OK_FAULT) {
 511                                         if (el->invalue != el->invalue_buf) {
 512                                                 uint32_t invalue = le_to_h_u32(el->invalue);
 513                                                 memcpy(el->invalue, &invalue, sizeof(uint32_t));
 514                                         }
 515                                         break;
 516                                 }
 517                                 if (el->ack != JTAG_ACK_WAIT) {
 518                                         LOG_ERROR("Invalid ACK (%1x) in DAP response", el->ack);
 519                                         log_dap_cmd("ERR", el);
 520                                         retval = ERROR_JTAG_DEVICE_ERROR;
 521                                         break;
 522                                 }
 523                         } while (timeval_ms() - time_now < 1000);
 524
 525                         if (retval == ERROR_OK) {
 526                                 if (el->ack != JTAG_ACK_OK_FAULT) {
 527                                         LOG_ERROR("Timeout during WAIT recovery");
 528                                         jtag_ap_q_abort(dap, NULL);
 529                                         retval = ERROR_JTAG_DEVICE_ERROR;
 530                                 }
 531                         } else
 532                                 break;
 533                 }
 534         }
 535
 536  done:
 537         flush_journal(&replay_list);
 538         flush_journal(&dap->cmd_journal);
 539         return retval;
 540 }
 541
 542 static int jtagdp_transaction_endcheck(struct adiv5_dap *dap)
 543 {
 544         int retval;
 545         uint32_t ctrlstat;
 546
 547         /* too expensive to call keep_alive() here */
 548
 549         /* Post CTRL/STAT read; discard any previous posted read value
 550          * but collect its ACK status.
 551          */
 552         retval = adi_jtag_scan_inout_check_u32(dap, JTAG_DP_DPACC,
 553                         DP_CTRL_STAT, DPAP_READ, 0, &ctrlstat, 0);
 554         if (retval != ERROR_OK)
 555                 goto done;
 556
 557         /* REVISIT also STICKYCMP, for pushed comparisons (nyet used) */
 558
 559         /* Check for STICKYERR */
 560         if (ctrlstat & SSTICKYERR) {
 561                 LOG_DEBUG("jtag-dp: CTRL/STAT 0x%" PRIx32, ctrlstat);
 562                 /* Check power to debug regions */
 563                 if ((ctrlstat & (CDBGPWRUPREQ | CDBGPWRUPACK | CSYSPWRUPREQ | CSYSPWRUPACK)) !=
 564                                                 (CDBGPWRUPREQ | CDBGPWRUPACK | CSYSPWRUPREQ | CSYSPWRUPACK)) {
 565                         LOG_ERROR("Debug regions are unpowered, an unexpected reset might have happened");
 566                         retval = ERROR_JTAG_DEVICE_ERROR;
 567                         goto done;
 568                 }
 569
 570                 if (ctrlstat & SSTICKYERR)
 571                         LOG_ERROR("JTAG-DP STICKY ERROR");
 572                 if (ctrlstat & SSTICKYORUN)
 573                         LOG_DEBUG("JTAG-DP STICKY OVERRUN");
 574
 575                 /* Clear Sticky Error Bits */
 576                 retval = adi_jtag_scan_inout_check_u32(dap, JTAG_DP_DPACC,
 577                                 DP_CTRL_STAT, DPAP_WRITE,
 578                                 dap->dp_ctrl_stat | SSTICKYERR, NULL, 0);
 579                 if (retval != ERROR_OK)
 580                         goto done;
 581
 582                 if (ctrlstat & SSTICKYERR) {
 583                         retval = ERROR_JTAG_DEVICE_ERROR;
 584                         goto done;
 585                 }
 586         }
 587
 588  done:
 589         flush_journal(&dap->cmd_journal);
 590         return retval;
 591 }
 592
 593 /*--------------------------------------------------------------------------*/
 594
 595 static int jtag_dp_q_read(struct adiv5_dap *dap, unsigned reg,
 596                 uint32_t *data)
 597 {
 598         int retval =  adi_jtag_dp_scan_u32(dap, JTAG_DP_DPACC, reg,
 599                         DPAP_READ, 0, dap->last_read, 0, NULL);
 600         dap->last_read = data;
 601         return retval;
 602 }
 603
 604 static int jtag_dp_q_write(struct adiv5_dap *dap, unsigned reg,
 605                 uint32_t data)
 606 {
 607         int retval =  adi_jtag_dp_scan_u32(dap, JTAG_DP_DPACC,
 608                         reg, DPAP_WRITE, data, dap->last_read, 0, NULL);
 609         dap->last_read = NULL;
 610         return retval;
 611 }
 612
 613 /** Select the AP register bank matching bits 7:4 of reg. */
 614 static int jtag_ap_q_bankselect(struct adiv5_ap *ap, unsigned reg)
 615 {
 616         struct adiv5_dap *dap = ap->dap;
 617         uint32_t sel = ((uint32_t)ap->ap_num << 24) | (reg & 0x000000F0);
 618
 619         if (sel == dap->select)
 620                 return ERROR_OK;
 621
 622         dap->select = sel;
 623
 624         return jtag_dp_q_write(dap, DP_SELECT, sel);
 625 }
 626
 627 static int jtag_ap_q_read(struct adiv5_ap *ap, unsigned reg,
 628                 uint32_t *data)
 629 {
 630         int retval = jtag_ap_q_bankselect(ap, reg);
 631         if (retval != ERROR_OK)
 632                 return retval;
 633
 634         retval =  adi_jtag_dp_scan_u32(ap->dap, JTAG_DP_APACC, reg,
 635                         DPAP_READ, 0, ap->dap->last_read, ap->memaccess_tck, NULL);
 636         ap->dap->last_read = data;
 637
 638         return retval;
 639 }
 640
 641 static int jtag_ap_q_write(struct adiv5_ap *ap, unsigned reg,
 642                 uint32_t data)
 643 {
 644         int retval = jtag_ap_q_bankselect(ap, reg);
 645         if (retval != ERROR_OK)
 646                 return retval;
 647
 648         retval =  adi_jtag_dp_scan_u32(ap->dap, JTAG_DP_APACC, reg,
 649                         DPAP_WRITE, data, ap->dap->last_read, ap->memaccess_tck, NULL);
 650         ap->dap->last_read = NULL;
 651         return retval;
 652 }
 653
 654 static int jtag_ap_q_abort(struct adiv5_dap *dap, uint8_t *ack)
 655 {
 656         /* for JTAG, this is the only valid ABORT register operation */
 657         int retval =  adi_jtag_dp_scan_u32(dap, JTAG_DP_ABORT,
 658                         0, DPAP_WRITE, 1, NULL, 0, NULL);
 659         if (retval != ERROR_OK)
 660                 return retval;
 661
 662         return jtag_execute_queue();
 663 }
 664
 665 static int jtag_dp_run(struct adiv5_dap *dap)
 666 {
 667         int retval;
 668         int retval2 = ERROR_OK;
 669
 670         retval = adi_jtag_finish_read(dap);
 671         if (retval != ERROR_OK)
 672                 goto done;
 673         retval2 = jtagdp_overrun_check(dap);
 674         retval = jtagdp_transaction_endcheck(dap);
 675
 676  done:
 677         return (retval2 != ERROR_OK) ? retval2 : retval;
 678 }
 679
 680 static int jtag_dp_sync(struct adiv5_dap *dap)
 681 {
 682         return jtagdp_overrun_check(dap);
 683 }
 684
 685 /* FIXME don't export ... just initialize as
 686  * part of DAP setup
 687 */
 688 const struct dap_ops jtag_dp_ops = {
 689         .queue_dp_read       = jtag_dp_q_read,
 690         .queue_dp_write      = jtag_dp_q_write,
 691         .queue_ap_read       = jtag_ap_q_read,
 692         .queue_ap_write      = jtag_ap_q_write,
 693         .queue_ap_abort      = jtag_ap_q_abort,
 694         .run                 = jtag_dp_run,
 695         .sync                = jtag_dp_sync,
 696 };
 697
 698
 699 static const uint8_t swd2jtag_bitseq[] = {
 700         /* More than 50 TCK/SWCLK cycles with TMS/SWDIO high,
 701          * putting both JTAG and SWD logic into reset state.
 702          */
 703         0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
 704         /* Switching equence disables SWD and enables JTAG
 705          * NOTE: bits in the DP's IDCODE can expose the need for
 706          * the old/deprecated sequence (0xae 0xde).
 707          */
 708         0x3c, 0xe7,
 709         /* At least 50 TCK/SWCLK cycles with TMS/SWDIO high,
 710          * putting both JTAG and SWD logic into reset state.
 711          * NOTE:  some docs say "at least 5".
 712          */
 713         0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
 714 };
 715
 716 /** Put the debug link into JTAG mode, if the target supports it.
 717  * The link's initial mode may be either SWD or JTAG.
 718  *
 719  * @param target Enters JTAG mode (if possible).
 720  *
 721  * Note that targets implemented with SW-DP do not support JTAG, and
 722  * that some targets which could otherwise support it may have been
 723  * configured to disable JTAG signaling
 724  *
 725  * @return ERROR_OK or else a fault code.
 726  */
 727 int dap_to_jtag(struct target *target)
 728 {
 729         int retval;
 730
 731         LOG_DEBUG("Enter JTAG mode");
 732
 733         /* REVISIT it's nasty to need to make calls to a "jtag"
 734          * subsystem if the link isn't in JTAG mode...
 735          */
 736
 737         retval = jtag_add_tms_seq(8 * sizeof(swd2jtag_bitseq),
 738                         swd2jtag_bitseq, TAP_RESET);
 739         if (retval == ERROR_OK)
 740                 retval = jtag_execute_queue();
 741
 742         /* REVISIT set up the DAP's ops vector for JTAG mode. */
 743
 744         return retval;
 745 }