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   1 /***************************************************************************
   2  *   Copyright (C) 2005 by Dominic Rath                                    *
   3  *   Dominic.Rath@gmx.de                                                   *
   4  *                                                                         *
   5  *   This program is free software; you can redistribute it and/or modify  *
   6  *   it under the terms of the GNU General Public License as published by  *
   7  *   the Free Software Foundation; either version 2 of the License, or     *
   8  *   (at your option) any later version.                                   *
   9  *                                                                         *
  10  *   This program is distributed in the hope that it will be useful,       *
  11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  13  *   GNU General Public License for more details.                          *
  14  *                                                                         *
  15  *   You should have received a copy of the GNU General Public License     *
  16  *   along with this program.  If not, see <http://www.gnu.org/licenses/>. *
  17  ***************************************************************************/
  18
  19 #ifdef HAVE_CONFIG_H
  20 #include "config.h"
  21 #endif
  22
  23 #include <jtag/interface.h>
  24
  25 #if PARPORT_USE_PPDEV == 1
  26 #include <linux/parport.h>
  27 #include <linux/ppdev.h>
  28 #include <sys/ioctl.h>
  29 #else   /* not PARPORT_USE_PPDEV */
  30 #ifndef _WIN32
  31 #include <sys/io.h>
  32 #endif
  33 #endif
  34
  35 #if PARPORT_USE_GIVEIO == 1
  36 #if IS_CYGWIN == 1
  37 #include <windows.h>
  38 #endif
  39 #endif
  40
  41 /**
  42  * @file
  43  * Support the Amontec Chameleon POD with JTAG Accelerator support.
  44  * This is a parallel port JTAG adapter with a CPLD between the
  45  * parallel port and the JTAG connection.  VHDL code running in the
  46  * CPLD significantly accelerates JTAG operations compared to the
  47  * bitbanging "Wiggler" style of most parallel port adapters.
  48  */
  49
  50 /* configuration */
  51 static uint16_t amt_jtagaccel_port;
  52
  53 /* interface variables
  54  */
  55 static uint8_t aw_control_rst;
  56 static uint8_t aw_control_fsm = 0x10;
  57 static uint8_t aw_control_baudrate = 0x20;
  58
  59 static int rtck_enabled;
  60
  61 #if PARPORT_USE_PPDEV == 1
  62 static int device_handle;
  63
  64 static const int addr_mode = IEEE1284_MODE_EPP | IEEE1284_ADDR;
  65
  66 /* FIXME do something sane when these ioctl/read/write calls fail. */
  67
  68 #define AMT_AW(val) \
  69         do { \
  70                 int __retval; \
  71                 \
  72                 __retval = ioctl(device_handle, PPSETMODE, &addr_mode); \
  73                 assert(__retval >= 0); \
  74                 __retval = write(device_handle, &val, 1); \
  75                 assert(__retval >= 0); \
  76         } while (0)
  77 #define AMT_AR(val) \
  78         do { \
  79                 int __retval; \
  80                 \
  81                 __retval = ioctl(device_handle, PPSETMODE, &addr_mode); \
  82                 assert(__retval >= 0); \
  83                 __retval = read(device_handle, &val, 1); \
  84                 assert(__retval >= 0); \
  85         } while (0)
  86
  87 static const int data_mode = IEEE1284_MODE_EPP | IEEE1284_DATA;
  88
  89 #define AMT_DW(val) \
  90         do { \
  91                 int __retval; \
  92                 \
  93                 __retval = ioctl(device_handle, PPSETMODE, &data_mode); \
  94                 assert(__retval >= 0); \
  95                 __retval = write(device_handle, &val, 1); \
  96                 assert(__retval >= 0); \
  97         } while (0)
  98 #define AMT_DR(val) \
  99         do { \
 100                 int __retval; \
 101                 \
 102                 __retval = ioctl(device_handle, PPSETMODE, &data_mode); \
 103                 assert(__retval >= 0); \
 104                 __retval = read(device_handle, &val, 1); \
 105                 assert(__retval >= 0); \
 106         } while (0)
 107
 108 #else
 109
 110 #define AMT_AW(val) do { outb(val, amt_jtagaccel_port + 3); } while (0)
 111 #define AMT_AR(val) do { val = inb(amt_jtagaccel_port + 3); } while (0)
 112 #define AMT_DW(val) do { outb(val, amt_jtagaccel_port + 4); } while (0)
 113 #define AMT_DR(val) do { val = inb(amt_jtagaccel_port + 4); } while (0)
 114
 115 #endif  /* PARPORT_USE_PPDEV */
 116
 117 /* tap_move[i][j]: tap movement command to go from state i to state j
 118  * 0: Test-Logic-Reset
 119  * 1: Run-Test/Idle
 120  * 2: Shift-DR
 121  * 3: Pause-DR
 122  * 4: Shift-IR
 123  * 5: Pause-IR
 124  */
 125 static const uint8_t amt_jtagaccel_tap_move[6][6][2] = {
 126         /*         RESET         IDLE        DRSHIFT       DRPAUSE       IRSHIFT       IRPAUSE             */
 127         { {0x1f, 0x00}, {0x0f, 0x00}, {0x05, 0x00}, {0x0a, 0x00}, {0x06, 0x00}, {0x96, 0x00} }, /* RESET */
 128         { {0x1f, 0x00}, {0x00, 0x00}, {0x04, 0x00}, {0x05, 0x00}, {0x06, 0x00}, {0x0b, 0x00} }, /* IDLE */
 129         { {0x1f, 0x00}, {0x0d, 0x00}, {0x00, 0x00}, {0x01, 0x00}, {0x8f, 0x09}, {0x8f, 0x01} }, /* DRSHIFT  */
 130         { {0x1f, 0x00}, {0x0c, 0x00}, {0x08, 0x00}, {0x00, 0x00}, {0x8f, 0x09}, {0x8f, 0x01} }, /* DRPAUSE  */
 131         { {0x1f, 0x00}, {0x0d, 0x00}, {0x07, 0x00}, {0x97, 0x00}, {0x00, 0x00}, {0x01, 0x00} }, /* IRSHIFT  */
 132         { {0x1f, 0x00}, {0x0c, 0x00}, {0x07, 0x00}, {0x97, 0x00}, {0x08, 0x00}, {0x00, 0x00} }, /* IRPAUSE  */
 133 };
 134
 135 static void amt_jtagaccel_reset(int trst, int srst)
 136 {
 137         if (trst == 1)
 138                 aw_control_rst |= 0x4;
 139         else if (trst == 0)
 140                 aw_control_rst &= ~0x4;
 141
 142         if (srst == 1)
 143                 aw_control_rst |= 0x1;
 144         else if (srst == 0)
 145                 aw_control_rst &= ~0x1;
 146
 147         AMT_AW(aw_control_rst);
 148 }
 149
 150 static int amt_jtagaccel_speed(int speed)
 151 {
 152         aw_control_baudrate &= 0xf0;
 153         aw_control_baudrate |= speed & 0x0f;
 154         AMT_AW(aw_control_baudrate);
 155
 156         return ERROR_OK;
 157 }
 158
 159 static void amt_jtagaccel_end_state(tap_state_t state)
 160 {
 161         if (tap_is_state_stable(state))
 162                 tap_set_end_state(state);
 163         else {
 164                 LOG_ERROR("BUG: %i is not a valid end state", state);
 165                 exit(-1);
 166         }
 167 }
 168
 169 static void amt_wait_scan_busy(void)
 170 {
 171         int timeout = 4096;
 172         uint8_t ar_status;
 173
 174         AMT_AR(ar_status);
 175         while (((ar_status) & 0x80) && (timeout-- > 0))
 176                 AMT_AR(ar_status);
 177
 178         if (ar_status & 0x80) {
 179                 LOG_ERROR(
 180                         "amt_jtagaccel timed out while waiting for end of scan, rtck was %s, last AR_STATUS: 0x%2.2x",
 181                         (rtck_enabled) ? "enabled" : "disabled",
 182                         ar_status);
 183                 exit(-1);
 184         }
 185 }
 186
 187 static void amt_jtagaccel_state_move(void)
 188 {
 189         uint8_t aw_scan_tms_5;
 190         uint8_t tms_scan[2];
 191
 192         tap_state_t cur_state = tap_get_state();
 193         tap_state_t end_state = tap_get_end_state();
 194
 195         tms_scan[0] = amt_jtagaccel_tap_move[tap_move_ndx(cur_state)][tap_move_ndx(end_state)][0];
 196         tms_scan[1] = amt_jtagaccel_tap_move[tap_move_ndx(cur_state)][tap_move_ndx(end_state)][1];
 197
 198         aw_scan_tms_5 = 0x40 | (tms_scan[0] & 0x1f);
 199         AMT_AW(aw_scan_tms_5);
 200         int jtag_speed = 0;
 201         int retval = jtag_get_speed(&jtag_speed);
 202         assert(retval == ERROR_OK);
 203         if (jtag_speed > 3 || rtck_enabled)
 204                 amt_wait_scan_busy();
 205
 206         if (tms_scan[0] & 0x80) {
 207                 aw_scan_tms_5 = 0x40 | (tms_scan[1] & 0x1f);
 208                 AMT_AW(aw_scan_tms_5);
 209                 if (jtag_speed > 3 || rtck_enabled)
 210                         amt_wait_scan_busy();
 211         }
 212
 213         tap_set_state(end_state);
 214 }
 215
 216 static void amt_jtagaccel_runtest(int num_cycles)
 217 {
 218         int i = 0;
 219         uint8_t aw_scan_tms_5;
 220         uint8_t aw_scan_tms_1to4;
 221
 222         tap_state_t saved_end_state = tap_get_end_state();
 223
 224         /* only do a state_move when we're not already in IDLE */
 225         if (tap_get_state() != TAP_IDLE) {
 226                 amt_jtagaccel_end_state(TAP_IDLE);
 227                 amt_jtagaccel_state_move();
 228         }
 229
 230         while (num_cycles - i >= 5) {
 231                 aw_scan_tms_5 = 0x40;
 232                 AMT_AW(aw_scan_tms_5);
 233                 i += 5;
 234         }
 235
 236         if (num_cycles - i > 0) {
 237                 aw_scan_tms_1to4 = 0x80 | ((num_cycles - i - 1) & 0x3) << 4;
 238                 AMT_AW(aw_scan_tms_1to4);
 239         }
 240
 241         amt_jtagaccel_end_state(saved_end_state);
 242         if (tap_get_state() != tap_get_end_state())
 243                 amt_jtagaccel_state_move();
 244 }
 245
 246 static void amt_jtagaccel_scan(bool ir_scan, enum scan_type type, uint8_t *buffer, int scan_size)
 247 {
 248         int bits_left = scan_size;
 249         int bit_count = 0;
 250         tap_state_t saved_end_state = tap_get_end_state();
 251         uint8_t aw_tdi_option;
 252         uint8_t dw_tdi_scan;
 253         uint8_t dr_tdo;
 254         uint8_t aw_tms_scan;
 255         uint8_t tms_scan[2];
 256         int jtag_speed_var;
 257         int retval = jtag_get_speed(&jtag_speed_var);
 258         assert(retval == ERROR_OK);
 259
 260         if (ir_scan)
 261                 amt_jtagaccel_end_state(TAP_IRSHIFT);
 262         else
 263                 amt_jtagaccel_end_state(TAP_DRSHIFT);
 264
 265         /* Only move if we're not already there */
 266         if (tap_get_state() != tap_get_end_state())
 267                 amt_jtagaccel_state_move();
 268
 269         amt_jtagaccel_end_state(saved_end_state);
 270
 271         /* handle unaligned bits at the beginning */
 272         if ((scan_size - 1) % 8) {
 273                 aw_tdi_option = 0x30 | (((scan_size - 1) % 8) - 1);
 274                 AMT_AW(aw_tdi_option);
 275
 276                 dw_tdi_scan = buf_get_u32(buffer, bit_count, (scan_size - 1) % 8) & 0xff;
 277                 AMT_DW(dw_tdi_scan);
 278                 if (jtag_speed_var > 3 || rtck_enabled)
 279                         amt_wait_scan_busy();
 280
 281                 if ((type == SCAN_IN) || (type == SCAN_IO)) {
 282                         AMT_DR(dr_tdo);
 283                         dr_tdo = dr_tdo >> (8 - ((scan_size - 1) % 8));
 284                         buf_set_u32(buffer, bit_count, (scan_size - 1) % 8, dr_tdo);
 285                 }
 286
 287                 bit_count += (scan_size - 1) % 8;
 288                 bits_left -= (scan_size - 1) % 8;
 289         }
 290
 291         while (bits_left - 1 >= 8) {
 292                 dw_tdi_scan = buf_get_u32(buffer, bit_count, 8) & 0xff;
 293                 AMT_DW(dw_tdi_scan);
 294                 if (jtag_speed_var > 3 || rtck_enabled)
 295                         amt_wait_scan_busy();
 296
 297                 if ((type == SCAN_IN) || (type == SCAN_IO)) {
 298                         AMT_DR(dr_tdo);
 299                         buf_set_u32(buffer, bit_count, 8, dr_tdo);
 300                 }
 301
 302                 bit_count += 8;
 303                 bits_left -= 8;
 304         }
 305
 306         tms_scan[0] =
 307                 amt_jtagaccel_tap_move[tap_move_ndx(tap_get_state())][tap_move_ndx(tap_get_end_state())][0];
 308         tms_scan[1] =
 309                 amt_jtagaccel_tap_move[tap_move_ndx(tap_get_state())][tap_move_ndx(tap_get_end_state())][1];
 310         aw_tms_scan = 0x40 | (tms_scan[0] & 0x1f) | (buf_get_u32(buffer, bit_count, 1) << 5);
 311         AMT_AW(aw_tms_scan);
 312         if (jtag_speed_var > 3 || rtck_enabled)
 313                 amt_wait_scan_busy();
 314
 315         if ((type == SCAN_IN) || (type == SCAN_IO)) {
 316                 AMT_DR(dr_tdo);
 317                 dr_tdo = dr_tdo >> 7;
 318                 buf_set_u32(buffer, bit_count, 1, dr_tdo);
 319         }
 320
 321         if (tms_scan[0] & 0x80) {
 322                 aw_tms_scan = 0x40 | (tms_scan[1] & 0x1f);
 323                 AMT_AW(aw_tms_scan);
 324                 if (jtag_speed_var > 3 || rtck_enabled)
 325                         amt_wait_scan_busy();
 326         }
 327         tap_set_state(tap_get_end_state());
 328 }
 329
 330 static int amt_jtagaccel_execute_queue(void)
 331 {
 332         struct jtag_command *cmd = jtag_command_queue;  /* currently processed command */
 333         int scan_size;
 334         enum scan_type type;
 335         uint8_t *buffer;
 336         int retval;
 337
 338         /* return ERROR_OK, unless a jtag_read_buffer returns a failed check
 339          * that wasn't handled by a caller-provided error handler
 340          */
 341         retval = ERROR_OK;
 342
 343         while (cmd) {
 344                 switch (cmd->type) {
 345                         case JTAG_RESET:
 346                                 LOG_DEBUG_IO("reset trst: %i srst %i",
 347                                                 cmd->cmd.reset->trst,
 348                                                 cmd->cmd.reset->srst);
 349                                 if (cmd->cmd.reset->trst == 1)
 350                                         tap_set_state(TAP_RESET);
 351                                 amt_jtagaccel_reset(cmd->cmd.reset->trst, cmd->cmd.reset->srst);
 352                                 break;
 353                         case JTAG_RUNTEST:
 354                                 LOG_DEBUG_IO("runtest %i cycles, end in %i",
 355                                                 cmd->cmd.runtest->num_cycles,
 356                                                 cmd->cmd.runtest->end_state);
 357                                 amt_jtagaccel_end_state(cmd->cmd.runtest->end_state);
 358                                 amt_jtagaccel_runtest(cmd->cmd.runtest->num_cycles);
 359                                 break;
 360                         case JTAG_TLR_RESET:
 361                                 LOG_DEBUG_IO("statemove end in %i", cmd->cmd.statemove->end_state);
 362                                 amt_jtagaccel_end_state(cmd->cmd.statemove->end_state);
 363                                 amt_jtagaccel_state_move();
 364                                 break;
 365                         case JTAG_SCAN:
 366                                 LOG_DEBUG_IO("scan end in %i", cmd->cmd.scan->end_state);
 367                                 amt_jtagaccel_end_state(cmd->cmd.scan->end_state);
 368                                 scan_size = jtag_build_buffer(cmd->cmd.scan, &buffer);
 369                                 type = jtag_scan_type(cmd->cmd.scan);
 370                                 amt_jtagaccel_scan(cmd->cmd.scan->ir_scan, type, buffer, scan_size);
 371                                 if (jtag_read_buffer(buffer, cmd->cmd.scan) != ERROR_OK)
 372                                         retval = ERROR_JTAG_QUEUE_FAILED;
 373                                 free(buffer);
 374                                 break;
 375                         case JTAG_SLEEP:
 376                                 LOG_DEBUG_IO("sleep %" PRIu32, cmd->cmd.sleep->us);
 377                                 jtag_sleep(cmd->cmd.sleep->us);
 378                                 break;
 379                         default:
 380                                 LOG_ERROR("BUG: unknown JTAG command type encountered");
 381                                 exit(-1);
 382                 }
 383                 cmd = cmd->next;
 384         }
 385
 386         return retval;
 387 }
 388
 389 #if PARPORT_USE_GIVEIO == 1
 390 int amt_jtagaccel_get_giveio_access(void)
 391 {
 392         HANDLE h;
 393         OSVERSIONINFO version;
 394
 395         version.dwOSVersionInfoSize = sizeof(version);
 396         if (!GetVersionEx(&version)) {
 397                 errno = EINVAL;
 398                 return -1;
 399         }
 400         if (version.dwPlatformId != VER_PLATFORM_WIN32_NT)
 401                 return 0;
 402
 403         h = CreateFile("\\\\.\\giveio",
 404                         GENERIC_READ,
 405                         0,
 406                         NULL,
 407                         OPEN_EXISTING,
 408                         FILE_ATTRIBUTE_NORMAL,
 409                         NULL);
 410         if (h == INVALID_HANDLE_VALUE) {
 411                 errno = ENODEV;
 412                 return -1;
 413         }
 414
 415         CloseHandle(h);
 416
 417         return 0;
 418 }
 419 #endif
 420
 421 static int amt_jtagaccel_init(void)
 422 {
 423 #if PARPORT_USE_PPDEV == 1
 424         char buffer[256];
 425         int i = 0;
 426         uint8_t control_port;
 427 #else
 428         uint8_t status_port;
 429 #endif
 430         uint8_t ar_status;
 431
 432 #if PARPORT_USE_PPDEV == 1
 433         if (device_handle > 0) {
 434                 LOG_ERROR("device is already opened");
 435                 return ERROR_JTAG_INIT_FAILED;
 436         }
 437
 438         snprintf(buffer, 256, "/dev/parport%d", amt_jtagaccel_port);
 439         device_handle = open(buffer, O_RDWR);
 440
 441         if (device_handle < 0) {
 442                 LOG_ERROR(
 443                         "cannot open device. check it exists and that user read and write rights are set");
 444                 return ERROR_JTAG_INIT_FAILED;
 445         }
 446
 447         i = ioctl(device_handle, PPCLAIM);
 448         if (i < 0) {
 449                 LOG_ERROR("cannot claim device");
 450                 return ERROR_JTAG_INIT_FAILED;
 451         }
 452
 453         i = IEEE1284_MODE_EPP;
 454         i = ioctl(device_handle, PPSETMODE, &i);
 455         if (i < 0) {
 456                 LOG_ERROR(" cannot set compatible mode to device");
 457                 return ERROR_JTAG_INIT_FAILED;
 458         }
 459
 460         control_port = 0x00;
 461         i = ioctl(device_handle, PPWCONTROL, &control_port);
 462
 463         control_port = 0x04;
 464         i = ioctl(device_handle, PPWCONTROL, &control_port);
 465
 466 #else
 467         if (amt_jtagaccel_port == 0) {
 468                 amt_jtagaccel_port = 0x378;
 469                 LOG_WARNING("No parport port specified, using default '0x378' (LPT1)");
 470         }
 471
 472 #if PARPORT_USE_GIVEIO == 1
 473         if (amt_jtagaccel_get_giveio_access() != 0) {
 474 #else   /* PARPORT_USE_GIVEIO */
 475         if (ioperm(amt_jtagaccel_port, 5, 1) != 0) {
 476 #endif  /* PARPORT_USE_GIVEIO */
 477                 LOG_ERROR("missing privileges for direct i/o");
 478                 return ERROR_JTAG_INIT_FAILED;
 479         }
 480
 481         /* prepare epp port
 482          * clear timeout */
 483         status_port = inb(amt_jtagaccel_port + 1);
 484         outb(status_port | 0x1, amt_jtagaccel_port + 1);
 485
 486         /* reset epp port */
 487         outb(0x00, amt_jtagaccel_port + 2);
 488         outb(0x04, amt_jtagaccel_port + 2);
 489 #endif
 490
 491         if (rtck_enabled) {
 492                 /* set RTCK enable bit */
 493                 aw_control_fsm |= 0x02;
 494         }
 495
 496         /* enable JTAG port */
 497         aw_control_fsm |= 0x04;
 498         AMT_AW(aw_control_fsm);
 499
 500         enum reset_types jtag_reset_config = jtag_get_reset_config();
 501         if (jtag_reset_config & RESET_TRST_OPEN_DRAIN)
 502                 aw_control_rst &= ~0x8;
 503         else
 504                 aw_control_rst |= 0x8;
 505
 506         if (jtag_reset_config & RESET_SRST_PUSH_PULL)
 507                 aw_control_rst &= ~0x2;
 508         else
 509                 aw_control_rst |= 0x2;
 510
 511         amt_jtagaccel_reset(0, 0);
 512
 513         /* read status register */
 514         AMT_AR(ar_status);
 515         LOG_DEBUG("AR_STATUS: 0x%2.2x", ar_status);
 516
 517         return ERROR_OK;
 518 }
 519
 520 static int amt_jtagaccel_quit(void)
 521 {
 522
 523         return ERROR_OK;
 524 }
 525
 526 COMMAND_HANDLER(amt_jtagaccel_handle_parport_port_command)
 527 {
 528         if (CMD_ARGC == 1) {
 529                 /* only if the port wasn't overwritten by cmdline */
 530                 if (amt_jtagaccel_port == 0) {
 531                         uint16_t port;
 532                         COMMAND_PARSE_NUMBER(u16, CMD_ARGV[0], port);
 533                         amt_jtagaccel_port = port;
 534                 } else {
 535                         LOG_ERROR("The parport port was already configured!");
 536                         return ERROR_FAIL;
 537                 }
 538         }
 539
 540         command_print(CMD, "parport port = %u", amt_jtagaccel_port);
 541
 542         return ERROR_OK;
 543 }
 544
 545 COMMAND_HANDLER(amt_jtagaccel_handle_rtck_command)
 546 {
 547         if (CMD_ARGC == 0) {
 548                 command_print(CMD,
 549                         "amt_jtagaccel RTCK feature %s",
 550                         (rtck_enabled) ? "enabled" : "disabled");
 551                 return ERROR_OK;
 552         } else {
 553                 if (strcmp(CMD_ARGV[0], "enabled") == 0)
 554                         rtck_enabled = 1;
 555                 else
 556                         rtck_enabled = 0;
 557         }
 558
 559         return ERROR_OK;
 560 }
 561
 562 static const struct command_registration amtjtagaccel_command_handlers[] = {
 563         {
 564                 .name = "parport_port",
 565                 .handler = &amt_jtagaccel_handle_parport_port_command,
 566                 .mode = COMMAND_CONFIG,
 567                 .help = "configure or display the parallel port to use",
 568                 .usage = "[port_num]",
 569         },
 570         {
 571                 /**
 572                  * @todo Remove this "rtck" command; just use the standard
 573                  * mechanism to enable/disable adaptive clocking.  First
 574                  * implement the standard mechanism and deprecate "rtck";
 575                  * after a year or so, it'll be safe to remove this.
 576                  */
 577                 .name = "rtck",
 578                 .handler = &amt_jtagaccel_handle_rtck_command,
 579                 .mode = COMMAND_CONFIG,
 580                 .help = "configure or display RTCK support",
 581                 .usage = "[enable|disable]",
 582         },
 583         COMMAND_REGISTRATION_DONE
 584 };
 585
 586 static struct jtag_interface amt_jtagaccel_interface = {
 587         .execute_queue = amt_jtagaccel_execute_queue,
 588 };
 589
 590 struct adapter_driver amt_jtagaccel_adapter_driver = {
 591         .name = "amt_jtagaccel",
 592         .transports = jtag_only,
 593         .commands = amtjtagaccel_command_handlers,
 594
 595         .init = amt_jtagaccel_init,
 596         .quit = amt_jtagaccel_quit,
 597         .speed = amt_jtagaccel_speed,
 598
 599         .jtag_ops = &amt_jtagaccel_interface,
 600 };