src/target/openrisc/or1k_tap_mohor.c

   1 /***************************************************************************
   2  *   Copyright (C) 2013 by Franck Jullien                                  *
   3  *   elec4fun@gmail.com                                                    *
   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 "or1k_tap.h"
  24 #include "or1k.h"
  25
  26 #include <jtag/jtag.h>
  27
  28 #define OR1K_TAP_INST_DEBUG     0x8
  29
  30 static int or1k_tap_mohor_init(struct or1k_jtag *jtag_info)
  31 {
  32         LOG_DEBUG("Initialising OpenCores JTAG TAP");
  33
  34         /* Put TAP into state where it can talk to the debug interface
  35          * by shifting in correct value to IR.
  36          */
  37
  38         /* Ensure TAP is reset - maybe not necessary*/
  39         jtag_add_tlr();
  40
  41         struct jtag_tap *tap = jtag_info->tap;
  42         struct scan_field field;
  43         uint8_t ir_value = OR1K_TAP_INST_DEBUG;
  44
  45         field.num_bits = tap->ir_length;
  46         field.out_value = &ir_value;
  47         field.in_value = NULL;
  48
  49         jtag_add_ir_scan(tap, &field, TAP_IDLE);
  50
  51         return jtag_execute_queue();
  52 }
  53
  54 static struct or1k_tap_ip mohor_tap = {
  55         .name = "mohor",
  56         .init = or1k_tap_mohor_init,
  57 };
  58
  59 int or1k_tap_mohor_register(void)
  60 {
  61         list_add_tail(&mohor_tap.list, &tap_list);
  62         return 0;
  63 }