src/target/mips_ejtag.c

   1 /***************************************************************************
   2  *   Copyright (C) 2008 by Spencer Oliver                                  *
   3  *   spen@spen-soft.co.uk                                                  *
   4  *                                                                         *
   5  *   Copyright (C) 2008 by David T.L. Wong                                 *
   6  *                                                                         *
   7  *   Copyright (C) 2009 by David N. Claffey <dnclaffey@gmail.com>          *
   8  *                                                                         *
   9  *   This program is free software; you can redistribute it and/or modify  *
  10  *   it under the terms of the GNU General Public License as published by  *
  11  *   the Free Software Foundation; either version 2 of the License, or     *
  12  *   (at your option) any later version.                                   *
  13  *                                                                         *
  14  *   This program is distributed in the hope that it will be useful,       *
  15  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  16  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  17  *   GNU General Public License for more details.                          *
  18  *                                                                         *
  19  *   You should have received a copy of the GNU General Public License     *
  20  *   along with this program; if not, write to the                         *
  21  *   Free Software Foundation, Inc.,                                       *
  22  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
  23  ***************************************************************************/
  24
  25 #ifdef HAVE_CONFIG_H
  26 #include "config.h"
  27 #endif
  28
  29 #include "mips32.h"
  30 #include "mips_ejtag.h"
  31
  32 void mips_ejtag_set_instr(struct mips_ejtag *ejtag_info, int new_instr)
  33 {
  34         struct jtag_tap *tap;
  35
  36         tap = ejtag_info->tap;
  37         assert(tap != NULL);
  38
  39         if (buf_get_u32(tap->cur_instr, 0, tap->ir_length) != (uint32_t)new_instr) {
  40                 struct scan_field field;
  41                 uint8_t t[4];
  42
  43                 field.num_bits = tap->ir_length;
  44                 field.out_value = t;
  45                 buf_set_u32(t, 0, field.num_bits, new_instr);
  46                 field.in_value = NULL;
  47
  48                 jtag_add_ir_scan(tap, &field, TAP_IDLE);
  49         }
  50 }
  51
  52 int mips_ejtag_get_idcode(struct mips_ejtag *ejtag_info, uint32_t *idcode)
  53 {
  54         struct scan_field field;
  55         uint8_t r[4];
  56
  57         mips_ejtag_set_instr(ejtag_info, EJTAG_INST_IDCODE);
  58
  59         field.num_bits = 32;
  60         field.out_value = NULL;
  61         field.in_value = r;
  62
  63         jtag_add_dr_scan(ejtag_info->tap, 1, &field, TAP_IDLE);
  64
  65         int retval;
  66         retval = jtag_execute_queue();
  67         if (retval != ERROR_OK) {
  68                 LOG_ERROR("register read failed");
  69                 return retval;
  70         }
  71
  72         *idcode = buf_get_u32(field.in_value, 0, 32);
  73
  74         return ERROR_OK;
  75 }
  76
  77 static int mips_ejtag_get_impcode(struct mips_ejtag *ejtag_info, uint32_t *impcode)
  78 {
  79         struct scan_field field;
  80         uint8_t r[4];
  81
  82         mips_ejtag_set_instr(ejtag_info, EJTAG_INST_IMPCODE);
  83
  84         field.num_bits = 32;
  85         field.out_value = NULL;
  86         field.in_value = r;
  87
  88         jtag_add_dr_scan(ejtag_info->tap, 1, &field, TAP_IDLE);
  89
  90         int retval;
  91         retval = jtag_execute_queue();
  92         if (retval != ERROR_OK) {
  93                 LOG_ERROR("register read failed");
  94                 return retval;
  95         }
  96
  97         *impcode = buf_get_u32(field.in_value, 0, 32);
  98
  99         return ERROR_OK;
 100 }
 101
 102 int mips_ejtag_drscan_32(struct mips_ejtag *ejtag_info, uint32_t *data)
 103 {
 104         struct jtag_tap *tap;
 105         tap  = ejtag_info->tap;
 106         assert(tap != NULL);
 107
 108         struct scan_field field;
 109         uint8_t t[4], r[4];
 110         int retval;
 111
 112         field.num_bits = 32;
 113         field.out_value = t;
 114         buf_set_u32(t, 0, field.num_bits, *data);
 115         field.in_value = r;
 116
 117         jtag_add_dr_scan(tap, 1, &field, TAP_IDLE);
 118
 119         retval = jtag_execute_queue();
 120         if (retval != ERROR_OK) {
 121                 LOG_ERROR("register read failed");
 122                 return retval;
 123         }
 124
 125         *data = buf_get_u32(field.in_value, 0, 32);
 126
 127         keep_alive();
 128
 129         return ERROR_OK;
 130 }
 131
 132 void mips_ejtag_drscan_32_out(struct mips_ejtag *ejtag_info, uint32_t data)
 133 {
 134         uint8_t t[4];
 135         struct jtag_tap *tap;
 136         tap  = ejtag_info->tap;
 137         assert(tap != NULL);
 138
 139         struct scan_field field;
 140
 141         field.num_bits = 32;
 142         field.out_value = t;
 143         buf_set_u32(t, 0, field.num_bits, data);
 144
 145         field.in_value = NULL;
 146
 147         jtag_add_dr_scan(tap, 1, &field, TAP_IDLE);
 148 }
 149
 150 int mips_ejtag_drscan_8(struct mips_ejtag *ejtag_info, uint32_t *data)
 151 {
 152         struct jtag_tap *tap;
 153         tap  = ejtag_info->tap;
 154         assert(tap != NULL);
 155
 156         struct scan_field field;
 157         uint8_t t[4] = {0, 0, 0, 0}, r[4];
 158         int retval;
 159
 160         field.num_bits = 8;
 161         field.out_value = t;
 162         buf_set_u32(t, 0, field.num_bits, *data);
 163         field.in_value = r;
 164
 165         jtag_add_dr_scan(tap, 1, &field, TAP_IDLE);
 166
 167         retval = jtag_execute_queue();
 168         if (retval != ERROR_OK) {
 169                 LOG_ERROR("register read failed");
 170                 return retval;
 171         }
 172
 173         *data = buf_get_u32(field.in_value, 0, 32);
 174
 175         return ERROR_OK;
 176 }
 177
 178 void mips_ejtag_drscan_8_out(struct mips_ejtag *ejtag_info, uint8_t data)
 179 {
 180         struct jtag_tap *tap;
 181         tap  = ejtag_info->tap;
 182         assert(tap != NULL);
 183
 184         struct scan_field field;
 185
 186         field.num_bits = 8;
 187         field.out_value = &data;
 188         field.in_value = NULL;
 189
 190         jtag_add_dr_scan(tap, 1, &field, TAP_IDLE);
 191 }
 192
 193 /* Set (to enable) or clear (to disable stepping) the SSt bit (bit 8) in Cp0 Debug reg (reg 23, sel 0) */
 194 int mips_ejtag_config_step(struct mips_ejtag *ejtag_info, int enable_step)
 195 {
 196         int code_len = enable_step ? 6 : 7;
 197
 198         uint32_t *code = malloc(code_len * sizeof(uint32_t));
 199         if (code == NULL) {
 200                 LOG_ERROR("Out of memory");
 201                 return ERROR_FAIL;
 202         }
 203         uint32_t *code_p = code;
 204
 205         *code_p++ = MIPS32_MTC0(1, 31, 0);                      /* move $1 to COP0 DeSave */
 206         *code_p++ = MIPS32_MFC0(1, 23, 0),                      /* move COP0 Debug to $1 */
 207         *code_p++ = MIPS32_ORI(1, 1, 0x0100);                   /* set SSt bit in debug reg */
 208         if (!enable_step)
 209                 *code_p++ = MIPS32_XORI(1, 1, 0x0100);          /* clear SSt bit in debug reg */
 210
 211         *code_p++ = MIPS32_MTC0(1, 23, 0);                      /* move $1 to COP0 Debug */
 212         *code_p++ = MIPS32_B(NEG16((code_len - 1)));            /* jump to start */
 213         *code_p = MIPS32_MFC0(1, 31, 0);                        /* move COP0 DeSave to $1 */
 214
 215         int retval = mips32_pracc_exec(ejtag_info, code_len, code, 0, NULL, 0, NULL, 1);
 216
 217         free(code);
 218         return retval;
 219 }
 220
 221 int mips_ejtag_enter_debug(struct mips_ejtag *ejtag_info)
 222 {
 223         uint32_t ejtag_ctrl;
 224         mips_ejtag_set_instr(ejtag_info, EJTAG_INST_CONTROL);
 225
 226         /* set debug break bit */
 227         ejtag_ctrl = ejtag_info->ejtag_ctrl | EJTAG_CTRL_JTAGBRK;
 228         mips_ejtag_drscan_32(ejtag_info, &ejtag_ctrl);
 229
 230         /* break bit will be cleared by hardware */
 231         ejtag_ctrl = ejtag_info->ejtag_ctrl;
 232         mips_ejtag_drscan_32(ejtag_info, &ejtag_ctrl);
 233         LOG_DEBUG("ejtag_ctrl: 0x%8.8" PRIx32 "", ejtag_ctrl);
 234         if ((ejtag_ctrl & EJTAG_CTRL_BRKST) == 0) {
 235                 LOG_ERROR("Failed to enter Debug Mode!");
 236                 return ERROR_FAIL;
 237         }
 238
 239         return ERROR_OK;
 240 }
 241
 242 int mips_ejtag_exit_debug(struct mips_ejtag *ejtag_info)
 243 {
 244         uint32_t inst;
 245         inst = MIPS32_DRET;
 246
 247         /* execute our dret instruction */
 248         return mips32_pracc_exec(ejtag_info, 1, &inst, 0, NULL, 0, NULL, 0);
 249 }
 250
 251 int mips_ejtag_init(struct mips_ejtag *ejtag_info)
 252 {
 253         uint32_t ejtag_version;
 254         int retval;
 255
 256         retval = mips_ejtag_get_impcode(ejtag_info, &ejtag_info->impcode);
 257         if (retval != ERROR_OK)
 258                 return retval;
 259         LOG_DEBUG("impcode: 0x%8.8" PRIx32 "", ejtag_info->impcode);
 260
 261         /* get ejtag version */
 262         ejtag_version = ((ejtag_info->impcode >> 29) & 0x07);
 263
 264         switch (ejtag_version) {
 265                 case 0:
 266                         LOG_DEBUG("EJTAG: Version 1 or 2.0 Detected");
 267                         break;
 268                 case 1:
 269                         LOG_DEBUG("EJTAG: Version 2.5 Detected");
 270                         break;
 271                 case 2:
 272                         LOG_DEBUG("EJTAG: Version 2.6 Detected");
 273                         break;
 274                 case 3:
 275                         LOG_DEBUG("EJTAG: Version 3.1 Detected");
 276                         break;
 277                 case 4:
 278                         LOG_DEBUG("EJTAG: Version 4.1 Detected");
 279                         break;
 280                 case 5:
 281                         LOG_DEBUG("EJTAG: Version 5.1 Detected");
 282                         break;
 283                 default:
 284                         LOG_DEBUG("EJTAG: Unknown Version Detected");
 285                         break;
 286         }
 287         LOG_DEBUG("EJTAG: features:%s%s%s%s%s%s%s",
 288                 ejtag_info->impcode & EJTAG_IMP_R3K ? " R3k" : " R4k",
 289                 ejtag_info->impcode & EJTAG_IMP_DINT ? " DINT" : "",
 290                 ejtag_info->impcode & (1 << 22) ? " ASID_8" : "",
 291                 ejtag_info->impcode & (1 << 21) ? " ASID_6" : "",
 292                 ejtag_info->impcode & EJTAG_IMP_MIPS16 ? " MIPS16" : "",
 293                 ejtag_info->impcode & EJTAG_IMP_NODMA ? " noDMA" : " DMA",
 294                 ejtag_info->impcode & EJTAG_DCR_MIPS64  ? " MIPS64" : " MIPS32");
 295
 296         if ((ejtag_info->impcode & EJTAG_IMP_NODMA) == 0)
 297                 LOG_DEBUG("EJTAG: DMA Access Mode Support Enabled");
 298
 299         /* set initial state for ejtag control reg */
 300         ejtag_info->ejtag_ctrl = EJTAG_CTRL_ROCC | EJTAG_CTRL_PRACC | EJTAG_CTRL_PROBEN | EJTAG_CTRL_SETDEV;
 301         ejtag_info->fast_access_save = -1;
 302
 303         return ERROR_OK;
 304 }
 305
 306 int mips_ejtag_fastdata_scan(struct mips_ejtag *ejtag_info, int write_t, uint32_t *data)
 307 {
 308         struct jtag_tap *tap;
 309
 310         tap = ejtag_info->tap;
 311         assert(tap != NULL);
 312
 313         struct scan_field fields[2];
 314         uint8_t spracc = 0;
 315         uint8_t t[4] = {0, 0, 0, 0};
 316
 317         /* fastdata 1-bit register */
 318         fields[0].num_bits = 1;
 319         fields[0].out_value = &spracc;
 320         fields[0].in_value = NULL;
 321
 322         /* processor access data register 32 bit */
 323         fields[1].num_bits = 32;
 324         fields[1].out_value = t;
 325
 326         if (write_t) {
 327                 fields[1].in_value = NULL;
 328                 buf_set_u32(t, 0, 32, *data);
 329         } else
 330                 fields[1].in_value = (void *) data;
 331
 332         jtag_add_dr_scan(tap, 2, fields, TAP_IDLE);
 333
 334         if (!write_t && data)
 335                 jtag_add_callback(mips_le_to_h_u32,
 336                         (jtag_callback_data_t) data);
 337
 338         keep_alive();
 339
 340         return ERROR_OK;
 341 }