git.sur5r.net Git - openocd/blob - src/target/nds32_v3_common.c

   1 /***************************************************************************
   2  *   Copyright (C) 2013 Andes Technology                                   *
   3  *   Hsiangkai Wang <hkwang@andestech.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 "breakpoints.h"
  24 #include "nds32_reg.h"
  25 #include "nds32_disassembler.h"
  26 #include "nds32.h"
  27 #include "nds32_aice.h"
  28 #include "nds32_v3_common.h"
  29
  30 static struct nds32_v3_common_callback *v3_common_callback;
  31
  32 static int nds32_v3_register_mapping(struct nds32 *nds32, int reg_no)
  33 {
  34         if (reg_no == PC)
  35                 return IR11;
  36
  37         return reg_no;
  38 }
  39
  40 static int nds32_v3_get_debug_reason(struct nds32 *nds32, uint32_t *reason)
  41 {
  42         uint32_t edmsw;
  43         struct aice_port_s *aice = target_to_aice(nds32->target);
  44         aice_read_debug_reg(aice, NDS_EDM_SR_EDMSW, &edmsw);
  45
  46         *reason = (edmsw >> 12) & 0x0F;
  47
  48         return ERROR_OK;
  49 }
  50
  51 /**
  52  * Save processor state.  This is called after a HALT instruction
  53  * succeeds, and on other occasions the processor enters debug mode
  54  * (breakpoint, watchpoint, etc).
  55  */
  56 static int nds32_v3_debug_entry(struct nds32 *nds32, bool enable_watchpoint)
  57 {
  58         LOG_DEBUG("nds32_v3_debug_entry");
  59
  60         enum target_state backup_state = nds32->target->state;
  61         nds32->target->state = TARGET_HALTED;
  62
  63         if (nds32->init_arch_info_after_halted == false) {
  64                 /* init architecture info according to config registers */
  65                 CHECK_RETVAL(nds32_config(nds32));
  66
  67                 nds32->init_arch_info_after_halted = true;
  68         }
  69
  70         /* REVISIT entire cache should already be invalid !!! */
  71         register_cache_invalidate(nds32->core_cache);
  72
  73         /* deactivate all hardware breakpoints */
  74         CHECK_RETVAL(v3_common_callback->deactivate_hardware_breakpoint(nds32->target));
  75
  76         if (enable_watchpoint)
  77                 CHECK_RETVAL(v3_common_callback->deactivate_hardware_watchpoint(nds32->target));
  78
  79         struct breakpoint *syscall_break = &(nds32->syscall_break);
  80         if (nds32->virtual_hosting) {
  81                 if (syscall_break->set) {
  82                         /** disable virtual hosting */
  83
  84                         /* remove breakpoint at syscall entry */
  85                         target_remove_breakpoint(nds32->target, syscall_break);
  86                         syscall_break->set = 0;
  87
  88                         uint32_t value_pc;
  89                         nds32_get_mapped_reg(nds32, PC, &value_pc);
  90                         if (value_pc == syscall_break->address)
  91                                 /** process syscall for virtual hosting */
  92                                 nds32->hit_syscall = true;
  93                 }
  94         }
  95
  96         if (ERROR_OK != nds32_examine_debug_reason(nds32)) {
  97                 nds32->target->state = backup_state;
  98
  99                 /* re-activate all hardware breakpoints & watchpoints */
 100                 CHECK_RETVAL(v3_common_callback->activate_hardware_breakpoint(nds32->target));
 101
 102                 if (enable_watchpoint)
 103                         CHECK_RETVAL(v3_common_callback->activate_hardware_watchpoint(nds32->target));
 104
 105                 return ERROR_FAIL;
 106         }
 107
 108         /* Save registers. */
 109         nds32_full_context(nds32);
 110
 111         /* check interrupt level */
 112         v3_common_callback->check_interrupt_stack(nds32);
 113
 114         return ERROR_OK;
 115 }
 116
 117 /**
 118  * Restore processor state.
 119  */
 120 static int nds32_v3_leave_debug_state(struct nds32 *nds32, bool enable_watchpoint)
 121 {
 122         LOG_DEBUG("nds32_v3_leave_debug_state");
 123
 124         struct target *target = nds32->target;
 125
 126         /* activate all hardware breakpoints */
 127         CHECK_RETVAL(v3_common_callback->activate_hardware_breakpoint(target));
 128
 129         if (enable_watchpoint) {
 130                 /* activate all watchpoints */
 131                 CHECK_RETVAL(v3_common_callback->activate_hardware_watchpoint(target));
 132         }
 133
 134         /* restore interrupt stack */
 135         v3_common_callback->restore_interrupt_stack(nds32);
 136
 137         /* REVISIT once we start caring about MMU and cache state,
 138          * address it here ...
 139          */
 140
 141         /* restore PSW, PC, and R0 ... after flushing any modified
 142          * registers.
 143          */
 144         CHECK_RETVAL(nds32_restore_context(target));
 145
 146         if (nds32->virtual_hosting) {
 147                 /** enable virtual hosting */
 148                 uint32_t value_ir3;
 149                 uint32_t entry_size;
 150                 uint32_t syscall_address;
 151
 152                 /* get syscall entry address */
 153                 nds32_get_mapped_reg(nds32, IR3, &value_ir3);
 154                 entry_size = 0x4 << (((value_ir3 >> 14) & 0x3) << 1);
 155                 syscall_address = (value_ir3 & 0xFFFF0000) + entry_size * 8; /* The index of SYSCALL is 8 */
 156
 157                 if (nds32->hit_syscall) {
 158                         /* single step to skip syscall entry */
 159                         /* use IRET to skip syscall */
 160                         struct aice_port_s *aice = target_to_aice(target);
 161                         uint32_t value_ir9;
 162                         uint32_t value_ir6;
 163                         uint32_t syscall_id;
 164
 165                         nds32_get_mapped_reg(nds32, IR6, &value_ir6);
 166                         syscall_id = (value_ir6 >> 16) & 0x7FFF;
 167
 168                         if (syscall_id == NDS32_SYSCALL_EXIT) {
 169                                 /* If target hits exit syscall, do not use IRET to skip handler. */
 170                                 aice_step(aice);
 171                         } else {
 172                                 /* use api->read/write_reg to skip nds32 register cache */
 173                                 uint32_t value_dimbr;
 174                                 aice_read_debug_reg(aice, NDS_EDM_SR_DIMBR, &value_dimbr);
 175                                 aice_write_register(aice, IR11, value_dimbr + 0xC);
 176
 177                                 aice_read_register(aice, IR9, &value_ir9);
 178                                 value_ir9 += 4; /* syscall is always 4 bytes */
 179                                 aice_write_register(aice, IR9, value_ir9);
 180
 181                                 /* backup hardware breakpoint 0 */
 182                                 uint32_t backup_bpa, backup_bpam, backup_bpc;
 183                                 aice_read_debug_reg(aice, NDS_EDM_SR_BPA0, &backup_bpa);
 184                                 aice_read_debug_reg(aice, NDS_EDM_SR_BPAM0, &backup_bpam);
 185                                 aice_read_debug_reg(aice, NDS_EDM_SR_BPC0, &backup_bpc);
 186
 187                                 /* use hardware breakpoint 0 to stop cpu after skipping syscall */
 188                                 aice_write_debug_reg(aice, NDS_EDM_SR_BPA0, value_ir9);
 189                                 aice_write_debug_reg(aice, NDS_EDM_SR_BPAM0, 0);
 190                                 aice_write_debug_reg(aice, NDS_EDM_SR_BPC0, 0xA);
 191
 192                                 /* Execute two IRET.
 193                                  * First IRET is used to quit debug mode.
 194                                  * Second IRET is used to quit current syscall. */
 195                                 uint32_t dim_inst[4] = {NOP, NOP, IRET, IRET};
 196                                 aice_execute(aice, dim_inst, 4);
 197
 198                                 /* restore origin hardware breakpoint 0 */
 199                                 aice_write_debug_reg(aice, NDS_EDM_SR_BPA0, backup_bpa);
 200                                 aice_write_debug_reg(aice, NDS_EDM_SR_BPAM0, backup_bpam);
 201                                 aice_write_debug_reg(aice, NDS_EDM_SR_BPC0, backup_bpc);
 202                         }
 203
 204                         nds32->hit_syscall = false;
 205                 }
 206
 207                 /* insert breakpoint at syscall entry */
 208                 struct breakpoint *syscall_break = &(nds32->syscall_break);
 209
 210                 syscall_break->address = syscall_address;
 211                 syscall_break->type = BKPT_SOFT;
 212                 syscall_break->set = 1;
 213                 target_add_breakpoint(target, syscall_break);
 214         }
 215
 216         return ERROR_OK;
 217 }
 218
 219 static int nds32_v3_get_exception_address(struct nds32 *nds32,
 220                 uint32_t *address, uint32_t reason)
 221 {
 222         LOG_DEBUG("nds32_v3_get_exception_address");
 223
 224         struct aice_port_s *aice = target_to_aice(nds32->target);
 225         struct target *target = nds32->target;
 226         uint32_t edmsw;
 227         uint32_t edm_cfg;
 228         uint32_t match_bits;
 229         uint32_t match_count;
 230         int32_t i;
 231         static int32_t number_of_hard_break;
 232         uint32_t bp_control;
 233
 234         if (number_of_hard_break == 0) {
 235                 aice_read_debug_reg(aice, NDS_EDM_SR_EDM_CFG, &edm_cfg);
 236                 number_of_hard_break = (edm_cfg & 0x7) + 1;
 237         }
 238
 239         aice_read_debug_reg(aice, NDS_EDM_SR_EDMSW, &edmsw);
 240         /* clear matching bits (write-one-clear) */
 241         aice_write_debug_reg(aice, NDS_EDM_SR_EDMSW, edmsw);
 242         match_bits = (edmsw >> 4) & 0xFF;
 243         match_count = 0;
 244         for (i = 0 ; i < number_of_hard_break ; i++) {
 245                 if (match_bits & (1 << i)) {
 246                         aice_read_debug_reg(aice, NDS_EDM_SR_BPA0 + i, address);
 247                         match_count++;
 248
 249                         /* If target hits multiple read/access watchpoint,
 250                          * select the first one. */
 251                         aice_read_debug_reg(aice, NDS_EDM_SR_BPC0 + i, &bp_control);
 252                         if (0x3 == (bp_control & 0x3)) {
 253                                 match_count = 1;
 254                                 break;
 255                         }
 256                 }
 257         }
 258
 259         if (match_count > 1) { /* multiple hits */
 260                 *address = 0;
 261                 return ERROR_OK;
 262         } else if (match_count == 1) {
 263                 uint32_t val_pc;
 264                 uint32_t opcode;
 265                 struct nds32_instruction instruction;
 266                 struct watchpoint *wp;
 267                 bool hit;
 268
 269                 nds32_get_mapped_reg(nds32, PC, &val_pc);
 270
 271                 if ((NDS32_DEBUG_DATA_ADDR_WATCHPOINT_NEXT_PRECISE == reason) ||
 272                                 (NDS32_DEBUG_DATA_VALUE_WATCHPOINT_NEXT_PRECISE == reason)) {
 273                         if (edmsw & 0x4) /* check EDMSW.IS_16BIT */
 274                                 val_pc -= 2;
 275                         else
 276                                 val_pc -= 4;
 277                 }
 278
 279                 nds32_read_opcode(nds32, val_pc, &opcode);
 280                 nds32_evaluate_opcode(nds32, opcode, val_pc, &instruction);
 281
 282                 LOG_DEBUG("PC: 0x%08" PRIx32 ", access start: 0x%08" PRIx32 ", end: 0x%08" PRIx32,
 283                                 val_pc, instruction.access_start, instruction.access_end);
 284
 285                 /* check if multiple hits in the access range */
 286                 uint32_t in_range_watch_count = 0;
 287                 for (wp = target->watchpoints; wp; wp = wp->next) {
 288                         if ((instruction.access_start <= wp->address) &&
 289                                         (wp->address < instruction.access_end))
 290                                 in_range_watch_count++;
 291                 }
 292                 if (in_range_watch_count > 1) {
 293                         /* Hit LSMW instruction. */
 294                         *address = 0;
 295                         return ERROR_OK;
 296                 }
 297
 298                 /* dispel false match */
 299                 hit = false;
 300                 for (wp = target->watchpoints; wp; wp = wp->next) {
 301                         if (((*address ^ wp->address) & (~wp->mask)) == 0) {
 302                                 uint32_t watch_start;
 303                                 uint32_t watch_end;
 304
 305                                 watch_start = wp->address;
 306                                 watch_end = wp->address + wp->length;
 307
 308                                 if ((watch_end <= instruction.access_start) ||
 309                                                 (instruction.access_end <= watch_start))
 310                                         continue;
 311
 312                                 hit = true;
 313                                 break;
 314                         }
 315                 }
 316
 317                 if (hit)
 318                         return ERROR_OK;
 319                 else
 320                         return ERROR_FAIL;
 321         } else if (match_count == 0) {
 322                 /* global stop is precise exception */
 323                 if ((NDS32_DEBUG_LOAD_STORE_GLOBAL_STOP == reason) && nds32->global_stop) {
 324                         /* parse instruction to get correct access address */
 325                         uint32_t val_pc;
 326                         uint32_t opcode;
 327                         struct nds32_instruction instruction;
 328
 329                         nds32_get_mapped_reg(nds32, PC, &val_pc);
 330                         nds32_read_opcode(nds32, val_pc, &opcode);
 331                         nds32_evaluate_opcode(nds32, opcode, val_pc, &instruction);
 332
 333                         *address = instruction.access_start;
 334
 335                         return ERROR_OK;
 336                 }
 337         }
 338
 339         *address = 0xFFFFFFFF;
 340         return ERROR_FAIL;
 341 }
 342
 343 void nds32_v3_common_register_callback(struct nds32_v3_common_callback *callback)
 344 {
 345         v3_common_callback = callback;
 346 }
 347
 348 /** target_type functions: */
 349 /* target request support */
 350 int nds32_v3_target_request_data(struct target *target,
 351                 uint32_t size, uint8_t *buffer)
 352 {
 353         /* AndesCore could use DTR register to communicate with OpenOCD
 354          * to output messages
 355          * Target data will be put in buffer
 356          * The format of DTR is as follow
 357          * DTR[31:16] => length, DTR[15:8] => size, DTR[7:0] => target_req_cmd
 358          * target_req_cmd has three possible values:
 359          *   TARGET_REQ_TRACEMSG
 360          *   TARGET_REQ_DEBUGMSG
 361          *   TARGET_REQ_DEBUGCHAR
 362          * if size == 0, target will call target_asciimsg(),
 363          * else call target_hexmsg()
 364          */
 365         LOG_WARNING("Not implemented: %s", __func__);
 366
 367         return ERROR_OK;
 368 }
 369
 370 int nds32_v3_checksum_memory(struct target *target,
 371                 target_addr_t address, uint32_t count, uint32_t *checksum)
 372 {
 373         LOG_WARNING("Not implemented: %s", __func__);
 374
 375         return ERROR_FAIL;
 376 }
 377
 378 /**
 379  * find out which watchpoint hits
 380  * get exception address and compare the address to watchpoints
 381  */
 382 int nds32_v3_hit_watchpoint(struct target *target,
 383                 struct watchpoint **hit_watchpoint)
 384 {
 385         static struct watchpoint scan_all_watchpoint;
 386
 387         uint32_t exception_address;
 388         struct watchpoint *wp;
 389         struct nds32 *nds32 = target_to_nds32(target);
 390
 391         exception_address = nds32->watched_address;
 392
 393         if (exception_address == 0xFFFFFFFF)
 394                 return ERROR_FAIL;
 395
 396         if (exception_address == 0) {
 397                 scan_all_watchpoint.address = 0;
 398                 scan_all_watchpoint.rw = WPT_WRITE;
 399                 scan_all_watchpoint.next = 0;
 400                 scan_all_watchpoint.unique_id = 0x5CA8;
 401
 402                 *hit_watchpoint = &scan_all_watchpoint;
 403                 return ERROR_OK;
 404         }
 405
 406         for (wp = target->watchpoints; wp; wp = wp->next) {
 407                 if (((exception_address ^ wp->address) & (~wp->mask)) == 0) {
 408                         *hit_watchpoint = wp;
 409
 410                         return ERROR_OK;
 411                 }
 412         }
 413
 414         return ERROR_FAIL;
 415 }
 416
 417 int nds32_v3_target_create_common(struct target *target, struct nds32 *nds32)
 418 {
 419         nds32->register_map = nds32_v3_register_mapping;
 420         nds32->get_debug_reason = nds32_v3_get_debug_reason;
 421         nds32->enter_debug_state = nds32_v3_debug_entry;
 422         nds32->leave_debug_state = nds32_v3_leave_debug_state;
 423         nds32->get_watched_address = nds32_v3_get_exception_address;
 424
 425         /* Init target->arch_info in nds32_init_arch_info().
 426          * After this, user could use target_to_nds32() to get nds32 object */
 427         nds32_init_arch_info(target, nds32);
 428
 429         return ERROR_OK;
 430 }
 431
 432 int nds32_v3_run_algorithm(struct target *target,
 433                 int num_mem_params,
 434                 struct mem_param *mem_params,
 435                 int num_reg_params,
 436                 struct reg_param *reg_params,
 437                 target_addr_t entry_point,
 438                 target_addr_t exit_point,
 439                 int timeout_ms,
 440                 void *arch_info)
 441 {
 442         LOG_WARNING("Not implemented: %s", __func__);
 443
 444         return ERROR_FAIL;
 445 }
 446
 447 int nds32_v3_read_buffer(struct target *target, target_addr_t address,
 448                 uint32_t size, uint8_t *buffer)
 449 {
 450         struct nds32 *nds32 = target_to_nds32(target);
 451         struct nds32_memory *memory = &(nds32->memory);
 452
 453         if ((NDS_MEMORY_ACC_CPU == memory->access_channel) &&
 454                         (target->state != TARGET_HALTED)) {
 455                 LOG_WARNING("target was not halted");
 456                 return ERROR_TARGET_NOT_HALTED;
 457         }
 458
 459         target_addr_t physical_address;
 460         /* BUG: If access range crosses multiple pages, the translation will not correct
 461          * for second page or so. */
 462
 463         /* When DEX is set to one, hardware will enforce the following behavior without
 464          * modifying the corresponding control bits in PSW.
 465          *
 466          * Disable all interrupts
 467          * Become superuser mode
 468          * Turn off IT/DT
 469          * Use MMU_CFG.DE as the data access endian
 470          * Use MMU_CFG.DRDE as the device register access endian if MMU_CTL.DREE is asserted
 471          * Disable audio special features
 472          * Disable inline function call
 473          *
 474          * Because hardware will turn off IT/DT by default, it MUST translate virtual address
 475          * to physical address.
 476          */
 477         if (ERROR_OK == target->type->virt2phys(target, address, &physical_address))
 478                 address = physical_address;
 479         else
 480                 return ERROR_FAIL;
 481
 482         int result;
 483         struct aice_port_s *aice = target_to_aice(target);
 484         /* give arbitrary initial value to avoid warning messages */
 485         enum nds_memory_access origin_access_channel = NDS_MEMORY_ACC_CPU;
 486
 487         if (nds32->hit_syscall) {
 488                 /* Use bus mode to access memory during virtual hosting */
 489                 origin_access_channel = memory->access_channel;
 490                 memory->access_channel = NDS_MEMORY_ACC_BUS;
 491                 aice_memory_access(aice, NDS_MEMORY_ACC_BUS);
 492         }
 493
 494         result = nds32_read_buffer(target, address, size, buffer);
 495
 496         if (nds32->hit_syscall) {
 497                 /* Restore access_channel after virtual hosting */
 498                 memory->access_channel = origin_access_channel;
 499                 aice_memory_access(aice, origin_access_channel);
 500         }
 501
 502         return result;
 503 }
 504
 505 int nds32_v3_write_buffer(struct target *target, target_addr_t address,
 506                 uint32_t size, const uint8_t *buffer)
 507 {
 508         struct nds32 *nds32 = target_to_nds32(target);
 509         struct nds32_memory *memory = &(nds32->memory);
 510
 511         if ((NDS_MEMORY_ACC_CPU == memory->access_channel) &&
 512                         (target->state != TARGET_HALTED)) {
 513                 LOG_WARNING("target was not halted");
 514                 return ERROR_TARGET_NOT_HALTED;
 515         }
 516
 517         target_addr_t physical_address;
 518         /* BUG: If access range crosses multiple pages, the translation will not correct
 519          * for second page or so. */
 520
 521         /* When DEX is set to one, hardware will enforce the following behavior without
 522          * modifying the corresponding control bits in PSW.
 523          *
 524          * Disable all interrupts
 525          * Become superuser mode
 526          * Turn off IT/DT
 527          * Use MMU_CFG.DE as the data access endian
 528          * Use MMU_CFG.DRDE as the device register access endian if MMU_CTL.DREE is asserted
 529          * Disable audio special features
 530          * Disable inline function call
 531          *
 532          * Because hardware will turn off IT/DT by default, it MUST translate virtual address
 533          * to physical address.
 534          */
 535         if (ERROR_OK == target->type->virt2phys(target, address, &physical_address))
 536                 address = physical_address;
 537         else
 538                 return ERROR_FAIL;
 539
 540         if (nds32->hit_syscall) {
 541                 struct aice_port_s *aice = target_to_aice(target);
 542                 enum nds_memory_access origin_access_channel;
 543                 origin_access_channel = memory->access_channel;
 544
 545                 /* If target has no cache, use BUS mode to access memory. */
 546                 if ((memory->dcache.line_size == 0)
 547                         || (memory->dcache.enable == false)) {
 548                         /* There is no Dcache or Dcache is disabled. */
 549                         memory->access_channel = NDS_MEMORY_ACC_BUS;
 550                         aice_memory_access(aice, NDS_MEMORY_ACC_BUS);
 551                 }
 552
 553                 int result;
 554                 result = nds32_gdb_fileio_write_memory(nds32, address, size, buffer);
 555
 556                 if (NDS_MEMORY_ACC_CPU == origin_access_channel) {
 557                         memory->access_channel = NDS_MEMORY_ACC_CPU;
 558                         aice_memory_access(aice, NDS_MEMORY_ACC_CPU);
 559                 }
 560
 561                 return result;
 562         }
 563
 564         return nds32_write_buffer(target, address, size, buffer);
 565 }
 566
 567 int nds32_v3_read_memory(struct target *target, target_addr_t address,
 568                 uint32_t size, uint32_t count, uint8_t *buffer)
 569 {
 570         struct nds32 *nds32 = target_to_nds32(target);
 571         struct nds32_memory *memory = &(nds32->memory);
 572
 573         if ((NDS_MEMORY_ACC_CPU == memory->access_channel) &&
 574                         (target->state != TARGET_HALTED)) {
 575                 LOG_WARNING("target was not halted");
 576                 return ERROR_TARGET_NOT_HALTED;
 577         }
 578
 579         target_addr_t physical_address;
 580         /* BUG: If access range crosses multiple pages, the translation will not correct
 581          * for second page or so. */
 582
 583         /* When DEX is set to one, hardware will enforce the following behavior without
 584          * modifying the corresponding control bits in PSW.
 585          *
 586          * Disable all interrupts
 587          * Become superuser mode
 588          * Turn off IT/DT
 589          * Use MMU_CFG.DE as the data access endian
 590          * Use MMU_CFG.DRDE as the device register access endian if MMU_CTL.DREE is asserted
 591          * Disable audio special features
 592          * Disable inline function call
 593          *
 594          * Because hardware will turn off IT/DT by default, it MUST translate virtual address
 595          * to physical address.
 596          */
 597         if (ERROR_OK == target->type->virt2phys(target, address, &physical_address))
 598                 address = physical_address;
 599         else
 600                 return ERROR_FAIL;
 601
 602         struct aice_port_s *aice = target_to_aice(target);
 603         /* give arbitrary initial value to avoid warning messages */
 604         enum nds_memory_access origin_access_channel = NDS_MEMORY_ACC_CPU;
 605         int result;
 606
 607         if (nds32->hit_syscall) {
 608                 /* Use bus mode to access memory during virtual hosting */
 609                 origin_access_channel = memory->access_channel;
 610                 memory->access_channel = NDS_MEMORY_ACC_BUS;
 611                 aice_memory_access(aice, NDS_MEMORY_ACC_BUS);
 612         }
 613
 614         result = nds32_read_memory(target, address, size, count, buffer);
 615
 616         if (nds32->hit_syscall) {
 617                 /* Restore access_channel after virtual hosting */
 618                 memory->access_channel = origin_access_channel;
 619                 aice_memory_access(aice, origin_access_channel);
 620         }
 621
 622         return result;
 623 }
 624
 625 int nds32_v3_write_memory(struct target *target, target_addr_t address,
 626                 uint32_t size, uint32_t count, const uint8_t *buffer)
 627 {
 628         struct nds32 *nds32 = target_to_nds32(target);
 629         struct nds32_memory *memory = &(nds32->memory);
 630
 631         if ((NDS_MEMORY_ACC_CPU == memory->access_channel) &&
 632                         (target->state != TARGET_HALTED)) {
 633                 LOG_WARNING("target was not halted");
 634                 return ERROR_TARGET_NOT_HALTED;
 635         }
 636
 637         target_addr_t physical_address;
 638         /* BUG: If access range crosses multiple pages, the translation will not correct
 639          * for second page or so. */
 640
 641         /* When DEX is set to one, hardware will enforce the following behavior without
 642          * modifying the corresponding control bits in PSW.
 643          *
 644          * Disable all interrupts
 645          * Become superuser mode
 646          * Turn off IT/DT
 647          * Use MMU_CFG.DE as the data access endian
 648          * Use MMU_CFG.DRDE as the device register access endian if MMU_CTL.DREE is asserted
 649          * Disable audio special features
 650          * Disable inline function call
 651          *
 652          * Because hardware will turn off IT/DT by default, it MUST translate virtual address
 653          * to physical address.
 654          */
 655         if (ERROR_OK == target->type->virt2phys(target, address, &physical_address))
 656                 address = physical_address;
 657         else
 658                 return ERROR_FAIL;
 659
 660         return nds32_write_memory(target, address, size, count, buffer);
 661 }
 662
 663 int nds32_v3_init_target(struct command_context *cmd_ctx,
 664                 struct target *target)
 665 {
 666         /* Initialize anything we can set up without talking to the target */
 667         struct nds32 *nds32 = target_to_nds32(target);
 668
 669         nds32_init(nds32);
 670
 671         target->fileio_info = malloc(sizeof(struct gdb_fileio_info));
 672         target->fileio_info->identifier = NULL;
 673
 674         return ERROR_OK;
 675 }