src/target/armv7m.c

   1 /***************************************************************************
   2  *   Copyright (C) 2005 by Dominic Rath                                    *
   3  *   Dominic.Rath@gmx.de                                                   *
   4  *                                                                         *
   5  *   Copyright (C) 2006 by Magnus Lundin                                   *
   6  *   lundin@mlu.mine.nu                                                    *
   7  *                                                                         *
   8  *   Copyright (C) 2008 by Spencer Oliver                                  *
   9  *   spen@spen-soft.co.uk                                                  *
  10  *                                                                         *
  11  *   Copyright (C) 2007,2008 Øyvind Harboe                                 *
  12  *   oyvind.harboe@zylin.com                                               *
  13  *                                                                         *
  14  *   This program is free software; you can redistribute it and/or modify  *
  15  *   it under the terms of the GNU General Public License as published by  *
  16  *   the Free Software Foundation; either version 2 of the License, or     *
  17  *   (at your option) any later version.                                   *
  18  *                                                                         *
  19  *   This program is distributed in the hope that it will be useful,       *
  20  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  21  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  22  *   GNU General Public License for more details.                          *
  23  *                                                                         *
  24  *   You should have received a copy of the GNU General Public License     *
  25  *   along with this program; if not, write to the                         *
  26  *   Free Software Foundation, Inc.,                                       *
  27  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
  28  *                                                                         *
  29  *      ARMv7-M Architecture, Application Level Reference Manual               *
  30  *              ARM DDI 0405C (September 2008)                             *
  31  *                                                                         *
  32  ***************************************************************************/
  33 #ifdef HAVE_CONFIG_H
  34 #include "config.h"
  35 #endif
  36
  37 #include "breakpoints.h"
  38 #include "armv7m.h"
  39 #include "algorithm.h"
  40 #include "register.h"
  41
  42
  43 #if 0
  44 #define _DEBUG_INSTRUCTION_EXECUTION_
  45 #endif
  46
  47 /** Maps from enum armv7m_mode (except ARMV7M_MODE_ANY) to name. */
  48 char *armv7m_mode_strings[] =
  49 {
  50         "Thread", "Thread (User)", "Handler",
  51 };
  52
  53 static char *armv7m_exception_strings[] =
  54 {
  55         "", "Reset", "NMI", "HardFault",
  56         "MemManage", "BusFault", "UsageFault", "RESERVED",
  57         "RESERVED", "RESERVED", "RESERVED", "SVCall",
  58         "DebugMonitor", "RESERVED", "PendSV", "SysTick"
  59 };
  60
  61 #ifdef ARMV7_GDB_HACKS
  62 uint8_t armv7m_gdb_dummy_cpsr_value[] = {0, 0, 0, 0};
  63
  64 struct reg armv7m_gdb_dummy_cpsr_reg =
  65 {
  66         .name = "GDB dummy cpsr register",
  67         .value = armv7m_gdb_dummy_cpsr_value,
  68         .dirty = 0,
  69         .valid = 1,
  70         .size = 32,
  71         .arch_info = NULL,
  72 };
  73 #endif
  74
  75 /*
  76  * These registers are not memory-mapped.  The ARMv7-M profile includes
  77  * memory mapped registers too, such as for the NVIC (interrupt controller)
  78  * and SysTick (timer) modules; those can mostly be treated as peripherals.
  79  *
  80  * The ARMv6-M profile is almost identical in this respect, except that it
  81  * doesn't include basepri or faultmask registers.
  82  */
  83 static const struct {
  84         unsigned id;
  85         const char *name;
  86         unsigned bits;
  87 } armv7m_regs[] = {
  88         { ARMV7M_R0, "r0", 32 },
  89         { ARMV7M_R1, "r1", 32 },
  90         { ARMV7M_R2, "r2", 32 },
  91         { ARMV7M_R3, "r3", 32 },
  92
  93         { ARMV7M_R4, "r4", 32 },
  94         { ARMV7M_R5, "r5", 32 },
  95         { ARMV7M_R6, "r6", 32 },
  96         { ARMV7M_R7, "r7", 32 },
  97
  98         { ARMV7M_R8, "r8", 32 },
  99         { ARMV7M_R9, "r9", 32 },
 100         { ARMV7M_R10, "r10", 32 },
 101         { ARMV7M_R11, "r11", 32 },
 102
 103         { ARMV7M_R12, "r12", 32 },
 104         { ARMV7M_R13, "sp", 32 },
 105         { ARMV7M_R14, "lr", 32 },
 106         { ARMV7M_PC, "pc", 32 },
 107
 108         { ARMV7M_xPSR, "xPSR", 32 },
 109         { ARMV7M_MSP, "msp", 32 },
 110         { ARMV7M_PSP, "psp", 32 },
 111
 112         { ARMV7M_PRIMASK, "primask", 1 },
 113         { ARMV7M_BASEPRI, "basepri", 8 },
 114         { ARMV7M_FAULTMASK, "faultmask", 1 },
 115         { ARMV7M_CONTROL, "control", 2 },
 116 };
 117
 118 #define ARMV7M_NUM_REGS ARRAY_SIZE(armv7m_regs)
 119
 120 /**
 121  * Restores target context using the cache of core registers set up
 122  * by armv7m_build_reg_cache(), calling optional core-specific hooks.
 123  */
 124 int armv7m_restore_context(struct target *target)
 125 {
 126         int i;
 127         struct armv7m_common *armv7m = target_to_armv7m(target);
 128
 129         LOG_DEBUG(" ");
 130
 131         if (armv7m->pre_restore_context)
 132                 armv7m->pre_restore_context(target);
 133
 134         for (i = ARMV7M_NUM_REGS - 1; i >= 0; i--)
 135         {
 136                 if (armv7m->core_cache->reg_list[i].dirty)
 137                 {
 138                         armv7m->write_core_reg(target, i);
 139                 }
 140         }
 141
 142         return ERROR_OK;
 143 }
 144
 145 /* Core state functions */
 146
 147 /**
 148  * Maps ISR number (from xPSR) to name.
 149  * Note that while names and meanings for the first sixteen are standardized
 150  * (with zero not a true exception), external interrupts are only numbered.
 151  * They are assigned by vendors, which generally assign different numbers to
 152  * peripherals (such as UART0 or a USB peripheral controller).
 153  */
 154 char *armv7m_exception_string(int number)
 155 {
 156         static char enamebuf[32];
 157
 158         if ((number < 0) | (number > 511))
 159                 return "Invalid exception";
 160         if (number < 16)
 161                 return armv7m_exception_strings[number];
 162         sprintf(enamebuf, "External Interrupt(%i)", number - 16);
 163         return enamebuf;
 164 }
 165
 166 static int armv7m_get_core_reg(struct reg *reg)
 167 {
 168         int retval;
 169         struct armv7m_core_reg *armv7m_reg = reg->arch_info;
 170         struct target *target = armv7m_reg->target;
 171         struct armv7m_common *armv7m = target_to_armv7m(target);
 172
 173         if (target->state != TARGET_HALTED)
 174         {
 175                 return ERROR_TARGET_NOT_HALTED;
 176         }
 177
 178         retval = armv7m->read_core_reg(target, armv7m_reg->num);
 179
 180         return retval;
 181 }
 182
 183 static int armv7m_set_core_reg(struct reg *reg, uint8_t *buf)
 184 {
 185         struct armv7m_core_reg *armv7m_reg = reg->arch_info;
 186         struct target *target = armv7m_reg->target;
 187         uint32_t value = buf_get_u32(buf, 0, 32);
 188
 189         if (target->state != TARGET_HALTED)
 190         {
 191                 return ERROR_TARGET_NOT_HALTED;
 192         }
 193
 194         buf_set_u32(reg->value, 0, 32, value);
 195         reg->dirty = 1;
 196         reg->valid = 1;
 197
 198         return ERROR_OK;
 199 }
 200
 201 static int armv7m_read_core_reg(struct target *target, unsigned num)
 202 {
 203         uint32_t reg_value;
 204         int retval;
 205         struct armv7m_core_reg * armv7m_core_reg;
 206         struct armv7m_common *armv7m = target_to_armv7m(target);
 207
 208         if (num >= ARMV7M_NUM_REGS)
 209                 return ERROR_INVALID_ARGUMENTS;
 210
 211         armv7m_core_reg = armv7m->core_cache->reg_list[num].arch_info;
 212         retval = armv7m->load_core_reg_u32(target, armv7m_core_reg->type, armv7m_core_reg->num, &reg_value);
 213         buf_set_u32(armv7m->core_cache->reg_list[num].value, 0, 32, reg_value);
 214         armv7m->core_cache->reg_list[num].valid = 1;
 215         armv7m->core_cache->reg_list[num].dirty = 0;
 216
 217         return retval;
 218 }
 219
 220 static int armv7m_write_core_reg(struct target *target, unsigned num)
 221 {
 222         int retval;
 223         uint32_t reg_value;
 224         struct armv7m_core_reg *armv7m_core_reg;
 225         struct armv7m_common *armv7m = target_to_armv7m(target);
 226
 227         if (num >= ARMV7M_NUM_REGS)
 228                 return ERROR_INVALID_ARGUMENTS;
 229
 230         reg_value = buf_get_u32(armv7m->core_cache->reg_list[num].value, 0, 32);
 231         armv7m_core_reg = armv7m->core_cache->reg_list[num].arch_info;
 232         retval = armv7m->store_core_reg_u32(target, armv7m_core_reg->type, armv7m_core_reg->num, reg_value);
 233         if (retval != ERROR_OK)
 234         {
 235                 LOG_ERROR("JTAG failure");
 236                 armv7m->core_cache->reg_list[num].dirty = armv7m->core_cache->reg_list[num].valid;
 237                 return ERROR_JTAG_DEVICE_ERROR;
 238         }
 239         LOG_DEBUG("write core reg %i value 0x%" PRIx32 "", num , reg_value);
 240         armv7m->core_cache->reg_list[num].valid = 1;
 241         armv7m->core_cache->reg_list[num].dirty = 0;
 242
 243         return ERROR_OK;
 244 }
 245
 246 /**
 247  * Returns generic ARM userspace registers to GDB.
 248  * GDB doesn't quite understand that most ARMs don't have floating point
 249  * hardware, so this also fakes a set of long-obsolete FPA registers that
 250  * are not used in EABI based software stacks.
 251  */
 252 int armv7m_get_gdb_reg_list(struct target *target, struct reg **reg_list[], int *reg_list_size)
 253 {
 254         struct armv7m_common *armv7m = target_to_armv7m(target);
 255         int i;
 256
 257         *reg_list_size = 26;
 258         *reg_list = malloc(sizeof(struct reg*) * (*reg_list_size));
 259
 260         /*
 261          * GDB register packet format for ARM:
 262          *  - the first 16 registers are r0..r15
 263          *  - (obsolete) 8 FPA registers
 264          *  - (obsolete) FPA status
 265          *  - CPSR
 266          */
 267         for (i = 0; i < 16; i++)
 268         {
 269                 (*reg_list)[i] = &armv7m->core_cache->reg_list[i];
 270         }
 271
 272         for (i = 16; i < 24; i++)
 273                 (*reg_list)[i] = &arm_gdb_dummy_fp_reg;
 274         (*reg_list)[24] = &arm_gdb_dummy_fps_reg;
 275
 276 #ifdef ARMV7_GDB_HACKS
 277         /* use dummy cpsr reg otherwise gdb may try and set the thumb bit */
 278         (*reg_list)[25] = &armv7m_gdb_dummy_cpsr_reg;
 279
 280         /* ARMV7M is always in thumb mode, try to make GDB understand this
 281          * if it does not support this arch */
 282         *((char*)armv7m->arm.pc->value) |= 1;
 283 #else
 284         (*reg_list)[25] = &armv7m->core_cache->reg_list[ARMV7M_xPSR];
 285 #endif
 286
 287         return ERROR_OK;
 288 }
 289
 290 /** Runs a Thumb algorithm in the target. */
 291 int armv7m_run_algorithm(struct target *target,
 292         int num_mem_params, struct mem_param *mem_params,
 293         int num_reg_params, struct reg_param *reg_params,
 294         uint32_t entry_point, uint32_t exit_point,
 295         int timeout_ms, void *arch_info)
 296 {
 297         int retval;
 298
 299         retval = armv7m_start_algorithm(target,
 300                         num_mem_params, mem_params,
 301                         num_reg_params, reg_params,
 302                         entry_point, exit_point,
 303                         arch_info);
 304
 305         if (retval == ERROR_OK)
 306                 retval = armv7m_wait_algorithm(target,
 307                                 num_mem_params, mem_params,
 308                                 num_reg_params, reg_params,
 309                                 exit_point, timeout_ms,
 310                                 arch_info);
 311
 312         return retval;
 313 }
 314
 315 /** Starts a Thumb algorithm in the target. */
 316 int armv7m_start_algorithm(struct target *target,
 317         int num_mem_params, struct mem_param *mem_params,
 318         int num_reg_params, struct reg_param *reg_params,
 319         uint32_t entry_point, uint32_t exit_point,
 320         void *arch_info)
 321 {
 322         struct armv7m_common *armv7m = target_to_armv7m(target);
 323         struct armv7m_algorithm *armv7m_algorithm_info = arch_info;
 324         enum armv7m_mode core_mode = armv7m->core_mode;
 325         int retval = ERROR_OK;
 326
 327         /* NOTE: armv7m_run_algorithm requires that each algorithm uses a software breakpoint
 328          * at the exit point */
 329
 330         if (armv7m_algorithm_info->common_magic != ARMV7M_COMMON_MAGIC)
 331         {
 332                 LOG_ERROR("current target isn't an ARMV7M target");
 333                 return ERROR_TARGET_INVALID;
 334         }
 335
 336         if (target->state != TARGET_HALTED)
 337         {
 338                 LOG_WARNING("target not halted");
 339                 return ERROR_TARGET_NOT_HALTED;
 340         }
 341
 342         /* refresh core register cache */
 343         /* Not needed if core register cache is always consistent with target process state */
 344         for (unsigned i = 0; i < ARMV7M_NUM_REGS; i++)
 345         {
 346                 if (!armv7m->core_cache->reg_list[i].valid)
 347                         armv7m->read_core_reg(target, i);
 348                 armv7m_algorithm_info->context[i] = buf_get_u32(armv7m->core_cache->reg_list[i].value, 0, 32);
 349         }
 350
 351         for (int i = 0; i < num_mem_params; i++)
 352         {
 353                 // TODO: Write only out params
 354                 if ((retval = target_write_buffer(target, mem_params[i].address, mem_params[i].size, mem_params[i].value)) != ERROR_OK)
 355                         return retval;
 356         }
 357
 358         for (int i = 0; i < num_reg_params; i++)
 359         {
 360                 struct reg *reg = register_get_by_name(armv7m->core_cache, reg_params[i].reg_name, 0);
 361 //              uint32_t regvalue;
 362
 363                 if (!reg)
 364                 {
 365                         LOG_ERROR("BUG: register '%s' not found", reg_params[i].reg_name);
 366                         return ERROR_INVALID_ARGUMENTS;
 367                 }
 368
 369                 if (reg->size != reg_params[i].size)
 370                 {
 371                         LOG_ERROR("BUG: register '%s' size doesn't match reg_params[i].size", reg_params[i].reg_name);
 372                         return ERROR_INVALID_ARGUMENTS;
 373                 }
 374
 375 //              regvalue = buf_get_u32(reg_params[i].value, 0, 32);
 376                 armv7m_set_core_reg(reg, reg_params[i].value);
 377         }
 378
 379         if (armv7m_algorithm_info->core_mode != ARMV7M_MODE_ANY)
 380         {
 381                 LOG_DEBUG("setting core_mode: 0x%2.2x", armv7m_algorithm_info->core_mode);
 382                 buf_set_u32(armv7m->core_cache->reg_list[ARMV7M_CONTROL].value,
 383                                 0, 1, armv7m_algorithm_info->core_mode);
 384                 armv7m->core_cache->reg_list[ARMV7M_CONTROL].dirty = 1;
 385                 armv7m->core_cache->reg_list[ARMV7M_CONTROL].valid = 1;
 386         }
 387         armv7m_algorithm_info->core_mode = core_mode;
 388
 389         retval = target_resume(target, 0, entry_point, 1, 1);
 390
 391         return retval;
 392 }
 393
 394 /** Waits for an algorithm in the target. */
 395 int armv7m_wait_algorithm(struct target *target,
 396         int num_mem_params, struct mem_param *mem_params,
 397         int num_reg_params, struct reg_param *reg_params,
 398         uint32_t exit_point, int timeout_ms,
 399         void *arch_info)
 400 {
 401         struct armv7m_common *armv7m = target_to_armv7m(target);
 402         struct armv7m_algorithm *armv7m_algorithm_info = arch_info;
 403         int retval = ERROR_OK;
 404         uint32_t pc;
 405
 406         /* NOTE: armv7m_run_algorithm requires that each algorithm uses a software breakpoint
 407          * at the exit point */
 408
 409         if (armv7m_algorithm_info->common_magic != ARMV7M_COMMON_MAGIC)
 410         {
 411                 LOG_ERROR("current target isn't an ARMV7M target");
 412                 return ERROR_TARGET_INVALID;
 413         }
 414
 415         retval = target_wait_state(target, TARGET_HALTED, timeout_ms);
 416         /* If the target fails to halt due to the breakpoint, force a halt */
 417         if (retval != ERROR_OK || target->state != TARGET_HALTED)
 418         {
 419                 if ((retval = target_halt(target)) != ERROR_OK)
 420                         return retval;
 421                 if ((retval = target_wait_state(target, TARGET_HALTED, 500)) != ERROR_OK)
 422                 {
 423                         return retval;
 424                 }
 425                 return ERROR_TARGET_TIMEOUT;
 426         }
 427
 428         armv7m->load_core_reg_u32(target, ARMV7M_REGISTER_CORE_GP, 15, &pc);
 429         if (exit_point && (pc != exit_point))
 430         {
 431                 LOG_DEBUG("failed algorithm halted at 0x%" PRIx32 ", expected 0x%" PRIx32 , pc, exit_point);
 432                 return ERROR_TARGET_TIMEOUT;
 433         }
 434
 435         /* Read memory values to mem_params[] */
 436         for (int i = 0; i < num_mem_params; i++)
 437         {
 438                 if (mem_params[i].direction != PARAM_OUT)
 439                         if ((retval = target_read_buffer(target, mem_params[i].address, mem_params[i].size, mem_params[i].value)) != ERROR_OK)
 440                         {
 441                                 return retval;
 442                         }
 443         }
 444
 445         /* Copy core register values to reg_params[] */
 446         for (int i = 0; i < num_reg_params; i++)
 447         {
 448                 if (reg_params[i].direction != PARAM_OUT)
 449                 {
 450                         struct reg *reg = register_get_by_name(armv7m->core_cache, reg_params[i].reg_name, 0);
 451
 452                         if (!reg)
 453                         {
 454                                 LOG_ERROR("BUG: register '%s' not found", reg_params[i].reg_name);
 455                                 return ERROR_INVALID_ARGUMENTS;
 456                         }
 457
 458                         if (reg->size != reg_params[i].size)
 459                         {
 460                                 LOG_ERROR("BUG: register '%s' size doesn't match reg_params[i].size", reg_params[i].reg_name);
 461                                 return ERROR_INVALID_ARGUMENTS;
 462                         }
 463
 464                         buf_set_u32(reg_params[i].value, 0, 32, buf_get_u32(reg->value, 0, 32));
 465                 }
 466         }
 467
 468         for (int i = ARMV7M_NUM_REGS - 1; i >= 0; i--)
 469         {
 470                 uint32_t regvalue;
 471                 regvalue = buf_get_u32(armv7m->core_cache->reg_list[i].value, 0, 32);
 472                 if (regvalue != armv7m_algorithm_info->context[i])
 473                 {
 474                         LOG_DEBUG("restoring register %s with value 0x%8.8" PRIx32,
 475                                 armv7m->core_cache->reg_list[i].name, armv7m_algorithm_info->context[i]);
 476                         buf_set_u32(armv7m->core_cache->reg_list[i].value,
 477                                         0, 32, armv7m_algorithm_info->context[i]);
 478                         armv7m->core_cache->reg_list[i].valid = 1;
 479                         armv7m->core_cache->reg_list[i].dirty = 1;
 480                 }
 481         }
 482
 483         armv7m->core_mode = armv7m_algorithm_info->core_mode;
 484
 485         return retval;
 486 }
 487
 488 /** Logs summary of ARMv7-M state for a halted target. */
 489 int armv7m_arch_state(struct target *target)
 490 {
 491         struct armv7m_common *armv7m = target_to_armv7m(target);
 492         struct arm *arm = &armv7m->arm;
 493         uint32_t ctrl, sp;
 494
 495         ctrl = buf_get_u32(armv7m->core_cache->reg_list[ARMV7M_CONTROL].value, 0, 32);
 496         sp = buf_get_u32(armv7m->core_cache->reg_list[ARMV7M_R13].value, 0, 32);
 497
 498         LOG_USER("target halted due to %s, current mode: %s %s\n"
 499                 "xPSR: %#8.8" PRIx32 " pc: %#8.8" PRIx32 " %csp: %#8.8" PRIx32 "%s",
 500                 debug_reason_name(target),
 501                 armv7m_mode_strings[armv7m->core_mode],
 502                 armv7m_exception_string(armv7m->exception_number),
 503                 buf_get_u32(arm->cpsr->value, 0, 32),
 504                 buf_get_u32(arm->pc->value, 0, 32),
 505                 (ctrl & 0x02) ? 'p' : 'm',
 506                 sp,
 507                 arm->is_semihosting ? ", semihosting" : "");
 508
 509         return ERROR_OK;
 510 }
 511 static const struct reg_arch_type armv7m_reg_type = {
 512         .get = armv7m_get_core_reg,
 513         .set = armv7m_set_core_reg,
 514 };
 515
 516 /** Builds cache of architecturally defined registers.  */
 517 struct reg_cache *armv7m_build_reg_cache(struct target *target)
 518 {
 519         struct armv7m_common *armv7m = target_to_armv7m(target);
 520         struct arm *arm = &armv7m->arm;
 521         int num_regs = ARMV7M_NUM_REGS;
 522         struct reg_cache **cache_p = register_get_last_cache_p(&target->reg_cache);
 523         struct reg_cache *cache = malloc(sizeof(struct reg_cache));
 524         struct reg *reg_list = calloc(num_regs, sizeof(struct reg));
 525         struct armv7m_core_reg *arch_info = calloc(num_regs, sizeof(struct armv7m_core_reg));
 526         int i;
 527
 528 #ifdef ARMV7_GDB_HACKS
 529         register_init_dummy(&armv7m_gdb_dummy_cpsr_reg);
 530 #endif
 531
 532         /* Build the process context cache */
 533         cache->name = "arm v7m registers";
 534         cache->next = NULL;
 535         cache->reg_list = reg_list;
 536         cache->num_regs = num_regs;
 537         (*cache_p) = cache;
 538         armv7m->core_cache = cache;
 539
 540         for (i = 0; i < num_regs; i++)
 541         {
 542                 arch_info[i].num = armv7m_regs[i].id;
 543                 arch_info[i].target = target;
 544                 arch_info[i].armv7m_common = armv7m;
 545                 reg_list[i].name = armv7m_regs[i].name;
 546                 reg_list[i].size = armv7m_regs[i].bits;
 547                 reg_list[i].value = calloc(1, 4);
 548                 reg_list[i].dirty = 0;
 549                 reg_list[i].valid = 0;
 550                 reg_list[i].type = &armv7m_reg_type;
 551                 reg_list[i].arch_info = &arch_info[i];
 552         }
 553
 554         arm->cpsr = reg_list + ARMV7M_xPSR;
 555         arm->pc = reg_list + ARMV7M_PC;
 556         arm->core_cache = cache;
 557         return cache;
 558 }
 559
 560 static int armv7m_setup_semihosting(struct target *target, int enable)
 561 {
 562         /* nothing todo for armv7m */
 563         return ERROR_OK;
 564 }
 565
 566 /** Sets up target as a generic ARMv7-M core */
 567 int armv7m_init_arch_info(struct target *target, struct armv7m_common *armv7m)
 568 {
 569         struct arm *arm = &armv7m->arm;
 570
 571         armv7m->common_magic = ARMV7M_COMMON_MAGIC;
 572
 573         arm->core_type = ARM_MODE_THREAD;
 574         arm->arch_info = armv7m;
 575         arm->setup_semihosting = armv7m_setup_semihosting;
 576
 577         /* FIXME remove v7m-specific r/w core_reg functions;
 578          * use the generic ARM core support..
 579          */
 580         armv7m->read_core_reg = armv7m_read_core_reg;
 581         armv7m->write_core_reg = armv7m_write_core_reg;
 582
 583         return arm_init_arch_info(target, arm);
 584 }
 585
 586 /** Generates a CRC32 checksum of a memory region. */
 587 int armv7m_checksum_memory(struct target *target,
 588                 uint32_t address, uint32_t count, uint32_t* checksum)
 589 {
 590         struct working_area *crc_algorithm;
 591         struct armv7m_algorithm armv7m_info;
 592         struct reg_param reg_params[2];
 593         int retval;
 594
 595         /* see contib/loaders/checksum/armv7m_crc.s for src */
 596
 597         static const uint16_t cortex_m3_crc_code[] = {
 598                 0x4602,                                 /* mov  r2, r0 */
 599                 0xF04F, 0x30FF,                 /* mov  r0, #0xffffffff */
 600                 0x460B,                                 /* mov  r3, r1 */
 601                 0xF04F, 0x0400,                 /* mov  r4, #0 */
 602                 0xE013,                                 /* b    ncomp */
 603                                                                 /* nbyte: */
 604                 0x5D11,                                 /* ldrb r1, [r2, r4] */
 605                 0xF8DF, 0x7028,                 /* ldr          r7, CRC32XOR */
 606                 0xEA80, 0x6001,                 /* eor          r0, r0, r1, asl #24 */
 607
 608                 0xF04F, 0x0500,                 /* mov          r5, #0 */
 609                                                                 /* loop: */
 610                 0x2800,                                 /* cmp          r0, #0 */
 611                 0xEA4F, 0x0640,                 /* mov          r6, r0, asl #1 */
 612                 0xF105, 0x0501,                 /* add          r5, r5, #1 */
 613                 0x4630,                                 /* mov          r0, r6 */
 614                 0xBFB8,                                 /* it           lt */
 615                 0xEA86, 0x0007,                 /* eor          r0, r6, r7 */
 616                 0x2D08,                                 /* cmp          r5, #8 */
 617                 0xD1F4,                                 /* bne          loop */
 618
 619                 0xF104, 0x0401,                 /* add  r4, r4, #1 */
 620                                                                 /* ncomp: */
 621                 0x429C,                                 /* cmp  r4, r3 */
 622                 0xD1E9,                                 /* bne  nbyte */
 623                 0xBE00,                         /* bkpt #0 */
 624                 0x1DB7, 0x04C1                  /* CRC32XOR:    .word 0x04C11DB7 */
 625         };
 626
 627         uint32_t i;
 628
 629         retval = target_alloc_working_area(target, sizeof(cortex_m3_crc_code), &crc_algorithm);
 630         if (retval != ERROR_OK)
 631                 return retval;
 632
 633         /* convert flash writing code into a buffer in target endianness */
 634         for (i = 0; i < ARRAY_SIZE(cortex_m3_crc_code); i++) {
 635                 retval = target_write_u16(target, crc_algorithm->address + i*sizeof(uint16_t), cortex_m3_crc_code[i]);
 636                 if (retval != ERROR_OK)
 637                         goto cleanup;
 638         }
 639
 640         armv7m_info.common_magic = ARMV7M_COMMON_MAGIC;
 641         armv7m_info.core_mode = ARMV7M_MODE_ANY;
 642
 643         init_reg_param(&reg_params[0], "r0", 32, PARAM_IN_OUT);
 644         init_reg_param(&reg_params[1], "r1", 32, PARAM_OUT);
 645
 646         buf_set_u32(reg_params[0].value, 0, 32, address);
 647         buf_set_u32(reg_params[1].value, 0, 32, count);
 648
 649         int timeout = 20000 * (1 + (count / (1024 * 1024)));
 650
 651         retval = target_run_algorithm(target, 0, NULL, 2, reg_params, crc_algorithm->address,
 652                                       crc_algorithm->address + (sizeof(cortex_m3_crc_code) - 6),
 653                                       timeout, &armv7m_info);
 654
 655         if (retval == ERROR_OK)
 656                 *checksum = buf_get_u32(reg_params[0].value, 0, 32);
 657         else
 658                 LOG_ERROR("error executing cortex_m3 crc algorithm");
 659
 660         destroy_reg_param(&reg_params[0]);
 661         destroy_reg_param(&reg_params[1]);
 662
 663 cleanup:
 664         target_free_working_area(target, crc_algorithm);
 665
 666         return retval;
 667 }
 668
 669 /** Checks whether a memory region is zeroed. */
 670 int armv7m_blank_check_memory(struct target *target,
 671                 uint32_t address, uint32_t count, uint32_t* blank)
 672 {
 673         struct working_area *erase_check_algorithm;
 674         struct reg_param reg_params[3];
 675         struct armv7m_algorithm armv7m_info;
 676         int retval;
 677         uint32_t i;
 678
 679         static const uint16_t erase_check_code[] =
 680         {
 681                 /* loop: */
 682                 0xF810, 0x3B01,         /* ldrb r3, [r0], #1 */
 683                 0xEA02, 0x0203,         /* and  r2, r2, r3 */
 684                 0x3901,                         /* subs r1, r1, #1 */
 685                 0xD1F9,                         /* bne  loop */
 686                 0xBE00,                 /* bkpt #0 */
 687         };
 688
 689         /* make sure we have a working area */
 690         if (target_alloc_working_area(target, sizeof(erase_check_code), &erase_check_algorithm) != ERROR_OK)
 691         {
 692                 return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
 693         }
 694
 695         /* convert flash writing code into a buffer in target endianness */
 696         for (i = 0; i < ARRAY_SIZE(erase_check_code); i++)
 697                 target_write_u16(target, erase_check_algorithm->address + i*sizeof(uint16_t), erase_check_code[i]);
 698
 699         armv7m_info.common_magic = ARMV7M_COMMON_MAGIC;
 700         armv7m_info.core_mode = ARMV7M_MODE_ANY;
 701
 702         init_reg_param(&reg_params[0], "r0", 32, PARAM_OUT);
 703         buf_set_u32(reg_params[0].value, 0, 32, address);
 704
 705         init_reg_param(&reg_params[1], "r1", 32, PARAM_OUT);
 706         buf_set_u32(reg_params[1].value, 0, 32, count);
 707
 708         init_reg_param(&reg_params[2], "r2", 32, PARAM_IN_OUT);
 709         buf_set_u32(reg_params[2].value, 0, 32, 0xff);
 710
 711         retval = target_run_algorithm(target, 0, NULL, 3, reg_params, erase_check_algorithm->address,
 712                                       erase_check_algorithm->address + (sizeof(erase_check_code) - 2),
 713                                       10000, &armv7m_info);
 714
 715         if (retval == ERROR_OK)
 716                 *blank = buf_get_u32(reg_params[2].value, 0, 32);
 717
 718         destroy_reg_param(&reg_params[0]);
 719         destroy_reg_param(&reg_params[1]);
 720         destroy_reg_param(&reg_params[2]);
 721
 722         target_free_working_area(target, erase_check_algorithm);
 723
 724         return retval;
 725 }
 726
 727 int armv7m_maybe_skip_bkpt_inst(struct target *target, bool *inst_found)
 728 {
 729         struct armv7m_common *armv7m = target_to_armv7m(target);
 730         struct reg *r = armv7m->arm.pc;
 731         bool result = false;
 732
 733
 734         /* if we halted last time due to a bkpt instruction
 735          * then we have to manually step over it, otherwise
 736          * the core will break again */
 737
 738         if (target->debug_reason == DBG_REASON_BREAKPOINT)
 739         {
 740                 uint16_t op;
 741                 uint32_t pc = buf_get_u32(r->value, 0, 32);
 742
 743                 pc &= ~1;
 744                 if (target_read_u16(target, pc, &op) == ERROR_OK)
 745                 {
 746                         if ((op & 0xFF00) == 0xBE00)
 747                         {
 748                                 pc = buf_get_u32(r->value, 0, 32) + 2;
 749                                 buf_set_u32(r->value, 0, 32, pc);
 750                                 r->dirty = true;
 751                                 r->valid = true;
 752                                 result = true;
 753                                 LOG_DEBUG("Skipping over BKPT instruction");
 754                         }
 755                 }
 756         }
 757
 758         if (inst_found) {
 759                 *inst_found = result;
 760         }
 761
 762         return ERROR_OK;
 763 }
 764
 765 const struct command_registration armv7m_command_handlers[] = {
 766         {
 767                 .chain = arm_command_handlers,
 768         },
 769         {
 770                 .chain = dap_command_handlers,
 771         },
 772         COMMAND_REGISTRATION_DONE
 773 };