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  *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 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 #include "mips32_dmaacc.h"
  32
  33 void mips_ejtag_set_instr(struct mips_ejtag *ejtag_info, int new_instr)
  34 {
  35         struct jtag_tap *tap;
  36
  37         tap = ejtag_info->tap;
  38         assert(tap != NULL);
  39
  40         if (buf_get_u32(tap->cur_instr, 0, tap->ir_length) != (uint32_t)new_instr) {
  41                 struct scan_field field;
  42                 uint8_t t[4];
  43
  44                 field.num_bits = tap->ir_length;
  45                 field.out_value = t;
  46                 buf_set_u32(t, 0, field.num_bits, new_instr);
  47                 field.in_value = NULL;
  48
  49                 jtag_add_ir_scan(tap, &field, TAP_IDLE);
  50         }
  51 }
  52
  53 int mips_ejtag_get_idcode(struct mips_ejtag *ejtag_info, uint32_t *idcode)
  54 {
  55         struct scan_field field;
  56         uint8_t r[4];
  57
  58         mips_ejtag_set_instr(ejtag_info, EJTAG_INST_IDCODE);
  59
  60         field.num_bits = 32;
  61         field.out_value = NULL;
  62         field.in_value = r;
  63
  64         jtag_add_dr_scan(ejtag_info->tap, 1, &field, TAP_IDLE);
  65
  66         int retval;
  67         retval = jtag_execute_queue();
  68         if (retval != ERROR_OK) {
  69                 LOG_ERROR("register read failed");
  70                 return retval;
  71         }
  72
  73         *idcode = buf_get_u32(field.in_value, 0, 32);
  74
  75         return ERROR_OK;
  76 }
  77
  78 static int mips_ejtag_get_impcode(struct mips_ejtag *ejtag_info, uint32_t *impcode)
  79 {
  80         struct scan_field field;
  81         uint8_t r[4];
  82
  83         mips_ejtag_set_instr(ejtag_info, EJTAG_INST_IMPCODE);
  84
  85         field.num_bits = 32;
  86         field.out_value = NULL;
  87         field.in_value = r;
  88
  89         jtag_add_dr_scan(ejtag_info->tap, 1, &field, TAP_IDLE);
  90
  91         int retval;
  92         retval = jtag_execute_queue();
  93         if (retval != ERROR_OK) {
  94                 LOG_ERROR("register read failed");
  95                 return retval;
  96         }
  97
  98         *impcode = buf_get_u32(field.in_value, 0, 32);
  99
 100         return ERROR_OK;
 101 }
 102
 103 void mips_ejtag_add_scan_96(struct mips_ejtag *ejtag_info, uint32_t ctrl, uint32_t data, uint8_t *in_scan_buf)
 104 {
 105         assert(ejtag_info->tap != NULL);
 106         struct jtag_tap *tap = ejtag_info->tap;
 107
 108         struct scan_field field;
 109         uint8_t out_scan[12];
 110
 111         /* processor access "all" register 96 bit */
 112         field.num_bits = 96;
 113
 114         field.out_value = out_scan;
 115         buf_set_u32(out_scan, 0, 32, ctrl);
 116         buf_set_u32(out_scan + 4, 0, 32, data);
 117         buf_set_u32(out_scan + 8, 0, 32, 0);
 118
 119         field.in_value = in_scan_buf;
 120
 121         jtag_add_dr_scan(tap, 1, &field, TAP_IDLE);
 122
 123         keep_alive();
 124 }
 125
 126 int mips_ejtag_drscan_32(struct mips_ejtag *ejtag_info, uint32_t *data)
 127 {
 128         struct jtag_tap *tap;
 129         tap  = ejtag_info->tap;
 130         assert(tap != NULL);
 131
 132         struct scan_field field;
 133         uint8_t t[4], r[4];
 134         int retval;
 135
 136         field.num_bits = 32;
 137         field.out_value = t;
 138         buf_set_u32(t, 0, field.num_bits, *data);
 139         field.in_value = r;
 140
 141         jtag_add_dr_scan(tap, 1, &field, TAP_IDLE);
 142
 143         retval = jtag_execute_queue();
 144         if (retval != ERROR_OK) {
 145                 LOG_ERROR("register read failed");
 146                 return retval;
 147         }
 148
 149         *data = buf_get_u32(field.in_value, 0, 32);
 150
 151         keep_alive();
 152
 153         return ERROR_OK;
 154 }
 155
 156 void mips_ejtag_drscan_32_out(struct mips_ejtag *ejtag_info, uint32_t data)
 157 {
 158         uint8_t t[4];
 159         struct jtag_tap *tap;
 160         tap  = ejtag_info->tap;
 161         assert(tap != NULL);
 162
 163         struct scan_field field;
 164
 165         field.num_bits = 32;
 166         field.out_value = t;
 167         buf_set_u32(t, 0, field.num_bits, data);
 168
 169         field.in_value = NULL;
 170
 171         jtag_add_dr_scan(tap, 1, &field, TAP_IDLE);
 172 }
 173
 174 int mips_ejtag_drscan_8(struct mips_ejtag *ejtag_info, uint32_t *data)
 175 {
 176         struct jtag_tap *tap;
 177         tap  = ejtag_info->tap;
 178         assert(tap != NULL);
 179
 180         struct scan_field field;
 181         uint8_t t[4] = {0, 0, 0, 0}, r[4];
 182         int retval;
 183
 184         field.num_bits = 8;
 185         field.out_value = t;
 186         buf_set_u32(t, 0, field.num_bits, *data);
 187         field.in_value = r;
 188
 189         jtag_add_dr_scan(tap, 1, &field, TAP_IDLE);
 190
 191         retval = jtag_execute_queue();
 192         if (retval != ERROR_OK) {
 193                 LOG_ERROR("register read failed");
 194                 return retval;
 195         }
 196
 197         *data = buf_get_u32(field.in_value, 0, 32);
 198
 199         return ERROR_OK;
 200 }
 201
 202 void mips_ejtag_drscan_8_out(struct mips_ejtag *ejtag_info, uint8_t data)
 203 {
 204         struct jtag_tap *tap;
 205         tap  = ejtag_info->tap;
 206         assert(tap != NULL);
 207
 208         struct scan_field field;
 209
 210         field.num_bits = 8;
 211         field.out_value = &data;
 212         field.in_value = NULL;
 213
 214         jtag_add_dr_scan(tap, 1, &field, TAP_IDLE);
 215 }
 216
 217 /* Set (to enable) or clear (to disable stepping) the SSt bit (bit 8) in Cp0 Debug reg (reg 23, sel 0) */
 218 int mips_ejtag_config_step(struct mips_ejtag *ejtag_info, int enable_step)
 219 {
 220         struct pracc_queue_info ctx = {.max_code = 7};
 221         pracc_queue_init(&ctx);
 222         if (ctx.retval != ERROR_OK)
 223                 goto exit;
 224
 225         pracc_add(&ctx, 0, MIPS32_MFC0(8, 23, 0));                      /* move COP0 Debug to $8 */
 226         pracc_add(&ctx, 0, MIPS32_ORI(8, 8, 0x0100));                   /* set SSt bit in debug reg */
 227         if (!enable_step)
 228                 pracc_add(&ctx, 0, MIPS32_XORI(8, 8, 0x0100));          /* clear SSt bit in debug reg */
 229
 230         pracc_add(&ctx, 0, MIPS32_MTC0(8, 23, 0));                      /* move $8 to COP0 Debug */
 231         pracc_add(&ctx, 0, MIPS32_LUI(8, UPPER16(ejtag_info->reg8)));           /* restore upper 16 bits  of $8 */
 232         pracc_add(&ctx, 0, MIPS32_B(NEG16((ctx.code_count + 1))));                      /* jump to start */
 233         pracc_add(&ctx, 0, MIPS32_ORI(8, 8, LOWER16(ejtag_info->reg8)));        /* restore lower 16 bits of $8 */
 234
 235         ctx.retval = mips32_pracc_queue_exec(ejtag_info, &ctx, NULL);
 236 exit:
 237         pracc_queue_free(&ctx);
 238         return ctx.retval;
 239 }
 240
 241 /*
 242  * Disable memory protection for 0xFF20.0000–0xFF3F.FFFF
 243  * It is needed by EJTAG 1.5-2.0, especially for BMIPS CPUs
 244  * For example bcm7401 and others. At leas on some
 245  * CPUs, DebugMode wont start if this bit is not removed.
 246  */
 247 static int disable_dcr_mp(struct mips_ejtag *ejtag_info)
 248 {
 249         uint32_t dcr;
 250         int retval;
 251
 252         retval = mips32_dmaacc_read_mem(ejtag_info, EJTAG_DCR, 4, 1, &dcr);
 253         if (retval != ERROR_OK)
 254                 goto error;
 255
 256         dcr &= ~EJTAG_DCR_MP;
 257         retval = mips32_dmaacc_write_mem(ejtag_info, EJTAG_DCR, 4, 1, &dcr);
 258         if (retval != ERROR_OK)
 259                 goto error;
 260         return ERROR_OK;
 261 error:
 262         LOG_ERROR("Failed to remove DCR MPbit!");
 263         return retval;
 264 }
 265
 266 int mips_ejtag_enter_debug(struct mips_ejtag *ejtag_info)
 267 {
 268         uint32_t ejtag_ctrl;
 269         mips_ejtag_set_instr(ejtag_info, EJTAG_INST_CONTROL);
 270
 271         if (ejtag_info->ejtag_version == EJTAG_VERSION_20) {
 272                 if (disable_dcr_mp(ejtag_info) != ERROR_OK)
 273                         goto error;
 274         }
 275
 276         /* set debug break bit */
 277         ejtag_ctrl = ejtag_info->ejtag_ctrl | EJTAG_CTRL_JTAGBRK;
 278         mips_ejtag_drscan_32(ejtag_info, &ejtag_ctrl);
 279
 280         /* break bit will be cleared by hardware */
 281         ejtag_ctrl = ejtag_info->ejtag_ctrl;
 282         mips_ejtag_drscan_32(ejtag_info, &ejtag_ctrl);
 283         LOG_DEBUG("ejtag_ctrl: 0x%8.8" PRIx32 "", ejtag_ctrl);
 284         if ((ejtag_ctrl & EJTAG_CTRL_BRKST) == 0)
 285                 goto error;
 286
 287         return ERROR_OK;
 288 error:
 289         LOG_ERROR("Failed to enter Debug Mode!");
 290         return ERROR_FAIL;
 291 }
 292
 293 int mips_ejtag_exit_debug(struct mips_ejtag *ejtag_info)
 294 {
 295         uint32_t instr = MIPS32_DRET;
 296         struct pracc_queue_info ctx = {.max_code = 1, .pracc_list = &instr, .code_count = 1, .store_count = 0};
 297
 298         /* execute our dret instruction */
 299         ctx.retval = mips32_pracc_queue_exec(ejtag_info, &ctx, NULL);
 300
 301         /* pic32mx workaround, false pending at low core clock */
 302         jtag_add_sleep(1000);
 303         return ctx.retval;
 304 }
 305
 306 int mips_ejtag_init(struct mips_ejtag *ejtag_info)
 307 {
 308         int retval;
 309
 310         retval = mips_ejtag_get_impcode(ejtag_info, &ejtag_info->impcode);
 311         if (retval != ERROR_OK)
 312                 return retval;
 313         LOG_DEBUG("impcode: 0x%8.8" PRIx32 "", ejtag_info->impcode);
 314
 315         /* get ejtag version */
 316         ejtag_info->ejtag_version = ((ejtag_info->impcode >> 29) & 0x07);
 317
 318         switch (ejtag_info->ejtag_version) {
 319                 case EJTAG_VERSION_20:
 320                         LOG_DEBUG("EJTAG: Version 1 or 2.0 Detected");
 321                         break;
 322                 case EJTAG_VERSION_25:
 323                         LOG_DEBUG("EJTAG: Version 2.5 Detected");
 324                         break;
 325                 case EJTAG_VERSION_26:
 326                         LOG_DEBUG("EJTAG: Version 2.6 Detected");
 327                         break;
 328                 case EJTAG_VERSION_31:
 329                         LOG_DEBUG("EJTAG: Version 3.1 Detected");
 330                         break;
 331                 case EJTAG_VERSION_41:
 332                         LOG_DEBUG("EJTAG: Version 4.1 Detected");
 333                         break;
 334                 case EJTAG_VERSION_51:
 335                         LOG_DEBUG("EJTAG: Version 5.1 Detected");
 336                         break;
 337                 default:
 338                         LOG_DEBUG("EJTAG: Unknown Version Detected");
 339                         break;
 340         }
 341         LOG_DEBUG("EJTAG: features:%s%s%s%s%s%s%s",
 342                 ejtag_info->impcode & EJTAG_IMP_R3K ? " R3k" : " R4k",
 343                 ejtag_info->impcode & EJTAG_IMP_DINT ? " DINT" : "",
 344                 ejtag_info->impcode & (1 << 22) ? " ASID_8" : "",
 345                 ejtag_info->impcode & (1 << 21) ? " ASID_6" : "",
 346                 ejtag_info->impcode & EJTAG_IMP_MIPS16 ? " MIPS16" : "",
 347                 ejtag_info->impcode & EJTAG_IMP_NODMA ? " noDMA" : " DMA",
 348                 ejtag_info->impcode & EJTAG_DCR_MIPS64  ? " MIPS64" : " MIPS32");
 349
 350         if ((ejtag_info->impcode & EJTAG_IMP_NODMA) == 0)
 351                 LOG_DEBUG("EJTAG: DMA Access Mode Support Enabled");
 352
 353         /* set initial state for ejtag control reg */
 354         ejtag_info->ejtag_ctrl = EJTAG_CTRL_ROCC | EJTAG_CTRL_PRACC | EJTAG_CTRL_PROBEN | EJTAG_CTRL_SETDEV;
 355         ejtag_info->fast_access_save = -1;
 356
 357         return ERROR_OK;
 358 }
 359
 360 int mips_ejtag_fastdata_scan(struct mips_ejtag *ejtag_info, int write_t, uint32_t *data)
 361 {
 362         struct jtag_tap *tap;
 363
 364         tap = ejtag_info->tap;
 365         assert(tap != NULL);
 366
 367         struct scan_field fields[2];
 368         uint8_t spracc = 0;
 369         uint8_t t[4] = {0, 0, 0, 0};
 370
 371         /* fastdata 1-bit register */
 372         fields[0].num_bits = 1;
 373         fields[0].out_value = &spracc;
 374         fields[0].in_value = NULL;
 375
 376         /* processor access data register 32 bit */
 377         fields[1].num_bits = 32;
 378         fields[1].out_value = t;
 379
 380         if (write_t) {
 381                 fields[1].in_value = NULL;
 382                 buf_set_u32(t, 0, 32, *data);
 383         } else
 384                 fields[1].in_value = (void *) data;
 385
 386         jtag_add_dr_scan(tap, 2, fields, TAP_IDLE);
 387
 388         if (!write_t && data)
 389                 jtag_add_callback(mips_le_to_h_u32,
 390                         (jtag_callback_data_t) data);
 391
 392         keep_alive();
 393
 394         return ERROR_OK;
 395 }