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   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  *   Copyright (C) 2008 by Spencer Oliver                                  *
   9  *   spen@spen-soft.co.uk                                                  *
  10  *                                                                         *
  11  *   This program is free software; you can redistribute it and/or modify  *
  12  *   it under the terms of the GNU General Public License as published by  *
  13  *   the Free Software Foundation; either version 2 of the License, or     *
  14  *   (at your option) any later version.                                   *
  15  *                                                                         *
  16  *   This program is distributed in the hope that it will be useful,       *
  17  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  18  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  19  *   GNU General Public License for more details.                          *
  20  *                                                                         *
  21  *   You should have received a copy of the GNU General Public License     *
  22  *   along with this program; if not, write to the                         *
  23  *   Free Software Foundation, Inc.,                                       *
  24  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
  25  ***************************************************************************/
  26 #ifdef HAVE_CONFIG_H
  27 #include "config.h"
  28 #endif
  29
  30 #include "embeddedice.h"
  31 #include "register.h"
  32
  33 /**
  34  * @file
  35  *
  36  * This provides lowlevel glue to the EmbeddedICE (or EmbeddedICE-RT)
  37  * module found on scan chain 2 in ARM7, ARM9, and some other families
  38  * of ARM cores.  The module is called "EmbeddedICE-RT" if it has
  39  * monitor mode support.
  40  *
  41  * EmbeddedICE provides basic watchpoint/breakpoint hardware and a Debug
  42  * Communications Channel (DCC) used to read or write 32-bit words to
  43  * OpenOCD-aware code running on the target CPU.
  44  * Newer modules also include vector catch hardware.  Some versions
  45  * support hardware single-stepping, "monitor mode" debug (which is not
  46  * currently supported by OpenOCD), or extended reporting on why the
  47  * core entered debug mode.
  48  */
  49
  50 static int embeddedice_set_reg_w_exec(struct reg *reg, uint8_t *buf);
  51
  52 /*
  53  * From:  ARM9E-S TRM, DDI 0165, table C-4 (and similar, for other cores)
  54  */
  55 static const struct {
  56         char            *name;
  57         unsigned short  addr;
  58         unsigned short  width;
  59 } eice_regs[] = {
  60         [EICE_DBG_CTRL] = {
  61                 .name =         "debug_ctrl",
  62                 .addr =         0,
  63                 /* width is assigned based on EICE version */
  64         },
  65         [EICE_DBG_STAT] = {
  66                 .name =         "debug_status",
  67                 .addr =         1,
  68                 /* width is assigned based on EICE version */
  69         },
  70         [EICE_COMMS_CTRL] = {
  71                 .name =         "comms_ctrl",
  72                 .addr =         4,
  73                 .width =        6,
  74         },
  75         [EICE_COMMS_DATA] = {
  76                 .name =         "comms_data",
  77                 .addr =         5,
  78                 .width =        32,
  79         },
  80         [EICE_W0_ADDR_VALUE] = {
  81                 .name =         "watch_0_addr_value",
  82                 .addr =         8,
  83                 .width =        32,
  84         },
  85         [EICE_W0_ADDR_MASK] = {
  86                 .name =         "watch_0_addr_mask",
  87                 .addr =         9,
  88                 .width =        32,
  89         },
  90         [EICE_W0_DATA_VALUE ] = {
  91                 .name =         "watch_0_data_value",
  92                 .addr =         10,
  93                 .width =        32,
  94         },
  95         [EICE_W0_DATA_MASK] = {
  96                 .name =         "watch_0_data_mask",
  97                 .addr =         11,
  98                 .width =        32,
  99         },
 100         [EICE_W0_CONTROL_VALUE] = {
 101                 .name =         "watch_0_control_value",
 102                 .addr =         12,
 103                 .width =        9,
 104         },
 105         [EICE_W0_CONTROL_MASK] = {
 106                 .name =         "watch_0_control_mask",
 107                 .addr =         13,
 108                 .width =        8,
 109         },
 110         [EICE_W1_ADDR_VALUE] = {
 111                 .name =         "watch_1_addr_value",
 112                 .addr =         16,
 113                 .width =        32,
 114         },
 115         [EICE_W1_ADDR_MASK] = {
 116                 .name =         "watch_1_addr_mask",
 117                 .addr =         17,
 118                 .width =        32,
 119         },
 120         [EICE_W1_DATA_VALUE] = {
 121                 .name =         "watch_1_data_value",
 122                 .addr =         18,
 123                 .width =        32,
 124         },
 125         [EICE_W1_DATA_MASK] = {
 126                 .name =         "watch_1_data_mask",
 127                 .addr =         19,
 128                 .width =        32,
 129         },
 130         [EICE_W1_CONTROL_VALUE] = {
 131                 .name =         "watch_1_control_value",
 132                 .addr =         20,
 133                 .width =        9,
 134         },
 135         [EICE_W1_CONTROL_MASK] = {
 136                 .name =         "watch_1_control_mask",
 137                 .addr =         21,
 138                 .width =        8,
 139         },
 140         /* vector_catch isn't always present */
 141         [EICE_VEC_CATCH] = {
 142                 .name =         "vector_catch",
 143                 .addr =         2,
 144                 .width =        8,
 145         },
 146 };
 147
 148
 149 static int embeddedice_get_reg(struct reg *reg)
 150 {
 151         int retval;
 152
 153         if ((retval = embeddedice_read_reg(reg)) != ERROR_OK)
 154                 LOG_ERROR("error queueing EmbeddedICE register read");
 155         else if ((retval = jtag_execute_queue()) != ERROR_OK)
 156                 LOG_ERROR("EmbeddedICE register read failed");
 157
 158         return retval;
 159 }
 160
 161 static const struct reg_arch_type eice_reg_type = {
 162         .get = embeddedice_get_reg,
 163         .set = embeddedice_set_reg_w_exec,
 164 };
 165
 166 /**
 167  * Probe EmbeddedICE module and set up local records of its registers.
 168  * Different versions of the modules have different capabilities, such as
 169  * hardware support for vector_catch, single stepping, and monitor mode.
 170  */
 171 struct reg_cache *
 172 embeddedice_build_reg_cache(struct target *target, struct arm7_9_common *arm7_9)
 173 {
 174         int retval;
 175         struct reg_cache *reg_cache = malloc(sizeof(struct reg_cache));
 176         struct reg *reg_list = NULL;
 177         struct embeddedice_reg *arch_info = NULL;
 178         struct arm_jtag *jtag_info = &arm7_9->jtag_info;
 179         int num_regs = ARRAY_SIZE(eice_regs);
 180         int i;
 181         int eice_version = 0;
 182
 183         /* vector_catch isn't always present */
 184         if (!arm7_9->has_vector_catch)
 185                 num_regs--;
 186
 187         /* the actual registers are kept in two arrays */
 188         reg_list = calloc(num_regs, sizeof(struct reg));
 189         arch_info = calloc(num_regs, sizeof(struct embeddedice_reg));
 190
 191         /* fill in values for the reg cache */
 192         reg_cache->name = "EmbeddedICE registers";
 193         reg_cache->next = NULL;
 194         reg_cache->reg_list = reg_list;
 195         reg_cache->num_regs = num_regs;
 196
 197         /* FIXME the second watchpoint unit on Feroceon and Dragonite
 198          * seems not to work ... we should have a way to not set up
 199          * its four registers here!
 200          */
 201
 202         /* set up registers */
 203         for (i = 0; i < num_regs; i++)
 204         {
 205                 reg_list[i].name = eice_regs[i].name;
 206                 reg_list[i].size = eice_regs[i].width;
 207                 reg_list[i].dirty = 0;
 208                 reg_list[i].valid = 0;
 209                 reg_list[i].value = calloc(1, 4);
 210                 reg_list[i].arch_info = &arch_info[i];
 211                 reg_list[i].type = &eice_reg_type;
 212                 arch_info[i].addr = eice_regs[i].addr;
 213                 arch_info[i].jtag_info = jtag_info;
 214         }
 215
 216         /* identify EmbeddedICE version by reading DCC control register */
 217         embeddedice_read_reg(&reg_list[EICE_COMMS_CTRL]);
 218         if ((retval = jtag_execute_queue()) != ERROR_OK)
 219         {
 220                 for (i = 0; i < num_regs; i++)
 221                 {
 222                         free(reg_list[i].value);
 223                 }
 224                 free(reg_list);
 225                 free(reg_cache);
 226                 free(arch_info);
 227                 return NULL;
 228         }
 229
 230         eice_version = buf_get_u32(reg_list[EICE_COMMS_CTRL].value, 28, 4);
 231         LOG_INFO("Embedded ICE version %d", eice_version);
 232
 233         switch (eice_version)
 234         {
 235                 case 1:
 236                         /* ARM7TDMI r3, ARM7TDMI-S r3
 237                          *
 238                          * REVISIT docs say ARM7TDMI-S r4 uses version 1 but
 239                          * that it has 6-bit CTRL and 5-bit STAT... doc bug?
 240                          * ARM7TDMI r4 docs say EICE v4.
 241                          */
 242                         reg_list[EICE_DBG_CTRL].size = 3;
 243                         reg_list[EICE_DBG_STAT].size = 5;
 244                         break;
 245                 case 2:
 246                         /* ARM9TDMI */
 247                         reg_list[EICE_DBG_CTRL].size = 4;
 248                         reg_list[EICE_DBG_STAT].size = 5;
 249                         arm7_9->has_single_step = 1;
 250                         break;
 251                 case 3:
 252                         LOG_ERROR("EmbeddedICE v%d handling might be broken",
 253                                         eice_version);
 254                         reg_list[EICE_DBG_CTRL].size = 6;
 255                         reg_list[EICE_DBG_STAT].size = 5;
 256                         arm7_9->has_single_step = 1;
 257                         arm7_9->has_monitor_mode = 1;
 258                         break;
 259                 case 4:
 260                         /* ARM7TDMI r4 */
 261                         reg_list[EICE_DBG_CTRL].size = 6;
 262                         reg_list[EICE_DBG_STAT].size = 5;
 263                         arm7_9->has_monitor_mode = 1;
 264                         break;
 265                 case 5:
 266                         /* ARM9E-S rev 1 */
 267                         reg_list[EICE_DBG_CTRL].size = 6;
 268                         reg_list[EICE_DBG_STAT].size = 5;
 269                         arm7_9->has_single_step = 1;
 270                         arm7_9->has_monitor_mode = 1;
 271                         break;
 272                 case 6:
 273                         /* ARM7EJ-S, ARM9E-S rev 2, ARM9EJ-S */
 274                         reg_list[EICE_DBG_CTRL].size = 6;
 275                         reg_list[EICE_DBG_STAT].size = 10;
 276                         /* DBG_STAT has MOE bits */
 277                         arm7_9->has_monitor_mode = 1;
 278                         break;
 279                 case 7:
 280                         LOG_ERROR("EmbeddedICE v%d handling might be broken",
 281                                         eice_version);
 282                         reg_list[EICE_DBG_CTRL].size = 6;
 283                         reg_list[EICE_DBG_STAT].size = 5;
 284                         arm7_9->has_monitor_mode = 1;
 285                         break;
 286                 default:
 287                         /*
 288                          * The Feroceon implementation has the version number
 289                          * in some unusual bits.  Let feroceon.c validate it
 290                          * and do the appropriate setup itself.
 291                          */
 292                         if (strcmp(target_type_name(target), "feroceon") == 0 ||
 293                             strcmp(target_type_name(target), "dragonite") == 0)
 294                                 break;
 295                         LOG_ERROR("unknown EmbeddedICE version "
 296                                 "(comms ctrl: 0x%8.8" PRIx32 ")",
 297                                 buf_get_u32(reg_list[EICE_COMMS_CTRL].value, 0, 32));
 298         }
 299
 300         /* On Feroceon and Dragonite the second unit is seemingly missing. */
 301         LOG_INFO("%s: hardware has %d breakpoint/watchpoint unit%s",
 302                         target_name(target), arm7_9->wp_available_max,
 303                         (arm7_9->wp_available_max != 1) ? "s" : "");
 304
 305         return reg_cache;
 306 }
 307
 308 /**
 309  * Initialize EmbeddedICE module, if needed.
 310  */
 311 int embeddedice_setup(struct target *target)
 312 {
 313         int retval;
 314         struct arm7_9_common *arm7_9 = target_to_arm7_9(target);
 315
 316         /* Explicitly disable monitor mode.  For now we only support halting
 317          * debug ... we don't know how to talk with a resident debug monitor
 318          * that manages break requests.  ARM's "Angel Debug Monitor" is one
 319          * common example of such code.
 320          */
 321         if (arm7_9->has_monitor_mode)
 322         {
 323                 struct reg *dbg_ctrl = &arm7_9->eice_cache->reg_list[EICE_DBG_CTRL];
 324
 325                 embeddedice_read_reg(dbg_ctrl);
 326                 if ((retval = jtag_execute_queue()) != ERROR_OK)
 327                         return retval;
 328                 buf_set_u32(dbg_ctrl->value, 4, 1, 0);
 329                 embeddedice_set_reg_w_exec(dbg_ctrl, dbg_ctrl->value);
 330         }
 331         return jtag_execute_queue();
 332 }
 333
 334 /**
 335  * Queue a read for an EmbeddedICE register into the register cache,
 336  * optionally checking the value read.
 337  * Note that at this level, all registers are 32 bits wide.
 338  */
 339 int embeddedice_read_reg_w_check(struct reg *reg,
 340                 uint8_t *check_value, uint8_t *check_mask)
 341 {
 342         struct embeddedice_reg *ice_reg = reg->arch_info;
 343         uint8_t reg_addr = ice_reg->addr & 0x1f;
 344         struct scan_field fields[3];
 345         uint8_t field1_out[1];
 346         uint8_t field2_out[1];
 347         int retval;
 348
 349         retval = arm_jtag_scann(ice_reg->jtag_info, 0x2, TAP_IDLE);
 350         if (retval != ERROR_OK)
 351                 return retval;
 352
 353         retval = arm_jtag_set_instr(ice_reg->jtag_info, ice_reg->jtag_info->intest_instr, NULL, TAP_IDLE);
 354         if (retval != ERROR_OK)
 355                 return retval;
 356
 357         /* bits 31:0 -- data (ignored here) */
 358         fields[0].num_bits = 32;
 359         fields[0].out_value = reg->value;
 360         fields[0].in_value = NULL;
 361         fields[0].check_value = NULL;
 362         fields[0].check_mask = NULL;
 363
 364         /* bits 36:32 -- register */
 365         fields[1].num_bits = 5;
 366         fields[1].out_value = field1_out;
 367         field1_out[0] = reg_addr;
 368         fields[1].in_value = NULL;
 369         fields[1].check_value = NULL;
 370         fields[1].check_mask = NULL;
 371
 372         /* bit 37 -- 0/read */
 373         fields[2].num_bits = 1;
 374         fields[2].out_value = field2_out;
 375         field2_out[0] = 0;
 376         fields[2].in_value = NULL;
 377         fields[2].check_value = NULL;
 378         fields[2].check_mask = NULL;
 379
 380         /* traverse Update-DR, setting address for the next read */
 381         jtag_add_dr_scan(ice_reg->jtag_info->tap, 3, fields, TAP_IDLE);
 382
 383         /* bits 31:0 -- the data we're reading (and maybe checking) */
 384         fields[0].in_value = reg->value;
 385         fields[0].check_value = check_value;
 386         fields[0].check_mask = check_mask;
 387
 388         /* when reading the DCC data register, leaving the address field set to
 389          * EICE_COMMS_DATA would read the register twice
 390          * reading the control register is safe
 391          */
 392         field1_out[0] = eice_regs[EICE_COMMS_CTRL].addr;
 393
 394         /* traverse Update-DR, reading but with no other side effects */
 395         jtag_add_dr_scan_check(ice_reg->jtag_info->tap, 3, fields, TAP_IDLE);
 396
 397         return ERROR_OK;
 398 }
 399
 400 /**
 401  * Receive a block of size 32-bit words from the DCC.
 402  * We assume the target is always going to be fast enough (relative to
 403  * the JTAG clock) that the debugger won't need to poll the handshake
 404  * bit.  The JTAG clock is usually at least six times slower than the
 405  * functional clock, so the 50+ JTAG clocks needed to receive the word
 406  * allow hundreds of instruction cycles (per word) in the target.
 407  */
 408 int embeddedice_receive(struct arm_jtag *jtag_info, uint32_t *data, uint32_t size)
 409 {
 410         struct scan_field fields[3];
 411         uint8_t field1_out[1];
 412         uint8_t field2_out[1];
 413         int retval;
 414
 415         retval = arm_jtag_scann(jtag_info, 0x2, TAP_IDLE);
 416         if (retval != ERROR_OK)
 417                 return retval;
 418         retval = arm_jtag_set_instr(jtag_info, jtag_info->intest_instr, NULL, TAP_IDLE);
 419         if (retval != ERROR_OK)
 420                 return retval;
 421
 422         fields[0].num_bits = 32;
 423         fields[0].out_value = NULL;
 424         fields[0].in_value = NULL;
 425
 426         fields[1].num_bits = 5;
 427         fields[1].out_value = field1_out;
 428         field1_out[0] = eice_regs[EICE_COMMS_DATA].addr;
 429         fields[1].in_value = NULL;
 430
 431         fields[2].num_bits = 1;
 432         fields[2].out_value = field2_out;
 433         field2_out[0] = 0;
 434         fields[2].in_value = NULL;
 435
 436         jtag_add_dr_scan(jtag_info->tap, 3, fields, TAP_IDLE);
 437
 438         while (size > 0)
 439         {
 440                 /* when reading the last item, set the register address to the DCC control reg,
 441                  * to avoid reading additional data from the DCC data reg
 442                  */
 443                 if (size == 1)
 444                         field1_out[0] = eice_regs[EICE_COMMS_CTRL].addr;
 445
 446                 fields[0].in_value = (uint8_t *)data;
 447                 jtag_add_dr_scan(jtag_info->tap, 3, fields, TAP_IDLE);
 448                 jtag_add_callback(arm_le_to_h_u32, (jtag_callback_data_t)data);
 449
 450                 data++;
 451                 size--;
 452         }
 453
 454         return jtag_execute_queue();
 455 }
 456
 457 /**
 458  * Queue a read for an EmbeddedICE register into the register cache,
 459  * not checking the value read.
 460  */
 461 int embeddedice_read_reg(struct reg *reg)
 462 {
 463         return embeddedice_read_reg_w_check(reg, NULL, NULL);
 464 }
 465
 466 /**
 467  * Queue a write for an EmbeddedICE register, updating the register cache.
 468  * Uses embeddedice_write_reg().
 469  */
 470 void embeddedice_set_reg(struct reg *reg, uint32_t value)
 471 {
 472         embeddedice_write_reg(reg, value);
 473
 474         buf_set_u32(reg->value, 0, reg->size, value);
 475         reg->valid = 1;
 476         reg->dirty = 0;
 477
 478 }
 479
 480 /**
 481  * Write an EmbeddedICE register, updating the register cache.
 482  * Uses embeddedice_set_reg(); not queued.
 483  */
 484 static int embeddedice_set_reg_w_exec(struct reg *reg, uint8_t *buf)
 485 {
 486         int retval;
 487
 488         embeddedice_set_reg(reg, buf_get_u32(buf, 0, reg->size));
 489         if ((retval = jtag_execute_queue()) != ERROR_OK)
 490                 LOG_ERROR("register write failed");
 491         return retval;
 492 }
 493
 494 /**
 495  * Queue a write for an EmbeddedICE register, bypassing the register cache.
 496  */
 497 void embeddedice_write_reg(struct reg *reg, uint32_t value)
 498 {
 499         struct embeddedice_reg *ice_reg = reg->arch_info;
 500         int retval;
 501
 502         LOG_DEBUG("%i: 0x%8.8" PRIx32 "", ice_reg->addr, value);
 503
 504         retval = arm_jtag_scann(ice_reg->jtag_info, 0x2, TAP_IDLE);
 505
 506         retval = arm_jtag_set_instr(ice_reg->jtag_info, ice_reg->jtag_info->intest_instr, NULL, TAP_IDLE);
 507
 508         uint8_t reg_addr = ice_reg->addr & 0x1f;
 509         embeddedice_write_reg_inner(ice_reg->jtag_info->tap, reg_addr, value);
 510 }
 511
 512 /**
 513  * Queue a write for an EmbeddedICE register, using cached value.
 514  * Uses embeddedice_write_reg().
 515  */
 516 void embeddedice_store_reg(struct reg *reg)
 517 {
 518         embeddedice_write_reg(reg, buf_get_u32(reg->value, 0, reg->size));
 519 }
 520
 521 /**
 522  * Send a block of size 32-bit words to the DCC.
 523  * We assume the target is always going to be fast enough (relative to
 524  * the JTAG clock) that the debugger won't need to poll the handshake
 525  * bit.  The JTAG clock is usually at least six times slower than the
 526  * functional clock, so the 50+ JTAG clocks needed to receive the word
 527  * allow hundreds of instruction cycles (per word) in the target.
 528  */
 529 int embeddedice_send(struct arm_jtag *jtag_info, uint32_t *data, uint32_t size)
 530 {
 531         struct scan_field fields[3];
 532         uint8_t field0_out[4];
 533         uint8_t field1_out[1];
 534         uint8_t field2_out[1];
 535         int retval;
 536
 537         retval = arm_jtag_scann(jtag_info, 0x2, TAP_IDLE);
 538         if (retval != ERROR_OK)
 539                 return retval;
 540         retval = arm_jtag_set_instr(jtag_info, jtag_info->intest_instr, NULL, TAP_IDLE);
 541         if (retval != ERROR_OK)
 542                 return retval;
 543
 544         fields[0].num_bits = 32;
 545         fields[0].out_value = field0_out;
 546         fields[0].in_value = NULL;
 547
 548         fields[1].num_bits = 5;
 549         fields[1].out_value = field1_out;
 550         field1_out[0] = eice_regs[EICE_COMMS_DATA].addr;
 551         fields[1].in_value = NULL;
 552
 553         fields[2].num_bits = 1;
 554         fields[2].out_value = field2_out;
 555         field2_out[0] = 1;
 556
 557         fields[2].in_value = NULL;
 558
 559         while (size > 0)
 560         {
 561                 buf_set_u32(field0_out, 0, 32, *data);
 562                 jtag_add_dr_scan(jtag_info->tap, 3, fields, TAP_IDLE);
 563
 564                 data++;
 565                 size--;
 566         }
 567
 568         /* call to jtag_execute_queue() intentionally omitted */
 569         return ERROR_OK;
 570 }
 571
 572 /**
 573  * Poll DCC control register until read or write handshake completes.
 574  */
 575 int embeddedice_handshake(struct arm_jtag *jtag_info, int hsbit, uint32_t timeout)
 576 {
 577         struct scan_field fields[3];
 578         uint8_t field0_in[4];
 579         uint8_t field1_out[1];
 580         uint8_t field2_out[1];
 581         int retval;
 582         uint32_t hsact;
 583         struct timeval lap;
 584         struct timeval now;
 585
 586         if (hsbit == EICE_COMM_CTRL_WBIT)
 587                 hsact = 1;
 588         else if (hsbit == EICE_COMM_CTRL_RBIT)
 589                 hsact = 0;
 590         else
 591         {
 592                 LOG_ERROR("Invalid arguments");
 593                 return ERROR_INVALID_ARGUMENTS;
 594         }
 595
 596         retval = arm_jtag_scann(jtag_info, 0x2, TAP_IDLE);
 597         if (retval != ERROR_OK)
 598                 return retval;
 599         retval = arm_jtag_set_instr(jtag_info, jtag_info->intest_instr, NULL, TAP_IDLE);
 600         if (retval != ERROR_OK)
 601                 return retval;
 602
 603         fields[0].num_bits = 32;
 604         fields[0].out_value = NULL;
 605         fields[0].in_value = field0_in;
 606
 607         fields[1].num_bits = 5;
 608         fields[1].out_value = field1_out;
 609         field1_out[0] = eice_regs[EICE_COMMS_DATA].addr;
 610         fields[1].in_value = NULL;
 611
 612         fields[2].num_bits = 1;
 613         fields[2].out_value = field2_out;
 614         field2_out[0] = 0;
 615         fields[2].in_value = NULL;
 616
 617         jtag_add_dr_scan(jtag_info->tap, 3, fields, TAP_IDLE);
 618         gettimeofday(&lap, NULL);
 619         do {
 620                 jtag_add_dr_scan(jtag_info->tap, 3, fields, TAP_IDLE);
 621                 if ((retval = jtag_execute_queue()) != ERROR_OK)
 622                         return retval;
 623
 624                 if (buf_get_u32(field0_in, hsbit, 1) == hsact)
 625                         return ERROR_OK;
 626
 627                 gettimeofday(&now, NULL);
 628         } while ((uint32_t)((now.tv_sec - lap.tv_sec) * 1000
 629                         + (now.tv_usec - lap.tv_usec) / 1000) <= timeout);
 630
 631         LOG_ERROR("embeddedice handshake timeout");
 632         return ERROR_TARGET_TIMEOUT;
 633 }
 634
 635 #ifndef HAVE_JTAG_MINIDRIVER_H
 636 /**
 637  * This is an inner loop of the open loop DCC write of data to target
 638  */
 639 void embeddedice_write_dcc(struct jtag_tap *tap,
 640                 int reg_addr, const uint8_t *buffer, int little, int count)
 641 {
 642         int i;
 643
 644         for (i = 0; i < count; i++)
 645         {
 646                 embeddedice_write_reg_inner(tap, reg_addr,
 647                                 fast_target_buffer_get_u32(buffer, little));
 648                 buffer += 4;
 649         }
 650 }
 651 #else
 652 /* provided by minidriver */
 653 #endif