git.gag.com Git - fw/openocd/blob - src/target/armv8_dpm.c

   1 /*
   2  * Copyright (C) 2009 by David Brownell
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  */
  15
  16 #ifdef HAVE_CONFIG_H
  17 #include "config.h"
  18 #endif
  19
  20 #include "arm.h"
  21 #include "armv8.h"
  22 #include "armv8_dpm.h"
  23 #include <jtag/jtag.h>
  24 #include "register.h"
  25 #include "breakpoints.h"
  26 #include "target_type.h"
  27 #include "armv8_opcodes.h"
  28
  29 #include "helper/time_support.h"
  30
  31 /* T32 ITR format */
  32 #define T32_FMTITR(instr) (((instr & 0x0000FFFF) << 16) | ((instr & 0xFFFF0000) >> 16))
  33
  34 /**
  35  * @file
  36  * Implements various ARM DPM operations using architectural debug registers.
  37  * These routines layer over core-specific communication methods to cope with
  38  * implementation differences between cores like ARM1136 and Cortex-A8.
  39  *
  40  * The "Debug Programmers' Model" (DPM) for ARMv6 and ARMv7 is defined by
  41  * Part C (Debug Architecture) of the ARM Architecture Reference Manual,
  42  * ARMv7-A and ARMv7-R edition (ARM DDI 0406B).  In OpenOCD, DPM operations
  43  * are abstracted through internal programming interfaces to share code and
  44  * to minimize needless differences in debug behavior between cores.
  45  */
  46
  47 /**
  48  * Get core state from EDSCR, without necessity to retrieve CPSR
  49  */
  50 enum arm_state armv8_dpm_get_core_state(struct arm_dpm *dpm)
  51 {
  52         int el = (dpm->dscr >> 8) & 0x3;
  53         int rw = (dpm->dscr >> 10) & 0xF;
  54
  55         dpm->last_el = el;
  56
  57         /* In Debug state, each bit gives the current Execution state of each EL */
  58         if ((rw >> el) & 0b1)
  59                 return ARM_STATE_AARCH64;
  60
  61         return ARM_STATE_ARM;
  62 }
  63
  64 /*----------------------------------------------------------------------*/
  65
  66 static int dpmv8_write_dcc(struct armv8_common *armv8, uint32_t data)
  67 {
  68         return mem_ap_write_u32(armv8->debug_ap,
  69                                 armv8->debug_base + CPUV8_DBG_DTRRX, data);
  70 }
  71
  72 static int dpmv8_write_dcc_64(struct armv8_common *armv8, uint64_t data)
  73 {
  74         int ret;
  75         ret = mem_ap_write_u32(armv8->debug_ap,
  76                                armv8->debug_base + CPUV8_DBG_DTRRX, data);
  77         if (ret == ERROR_OK)
  78                 ret = mem_ap_write_u32(armv8->debug_ap,
  79                                 armv8->debug_base + CPUV8_DBG_DTRTX, data >> 32);
  80         return ret;
  81 }
  82
  83 static int dpmv8_read_dcc(struct armv8_common *armv8, uint32_t *data,
  84         uint32_t *dscr_p)
  85 {
  86         uint32_t dscr = DSCR_ITE;
  87         int retval;
  88
  89         if (dscr_p)
  90                 dscr = *dscr_p;
  91
  92         /* Wait for DTRRXfull */
  93         long long then = timeval_ms();
  94         while ((dscr & DSCR_DTR_TX_FULL) == 0) {
  95                 retval = mem_ap_read_atomic_u32(armv8->debug_ap,
  96                                 armv8->debug_base + CPUV8_DBG_DSCR,
  97                                 &dscr);
  98                 if (retval != ERROR_OK)
  99                         return retval;
 100                 if (timeval_ms() > then + 1000) {
 101                         LOG_ERROR("Timeout waiting for read dcc");
 102                         return ERROR_FAIL;
 103                 }
 104         }
 105
 106         retval = mem_ap_read_atomic_u32(armv8->debug_ap,
 107                                             armv8->debug_base + CPUV8_DBG_DTRTX,
 108                                             data);
 109         if (retval != ERROR_OK)
 110                 return retval;
 111
 112         if (dscr_p)
 113                 *dscr_p = dscr;
 114
 115         return retval;
 116 }
 117
 118 static int dpmv8_read_dcc_64(struct armv8_common *armv8, uint64_t *data,
 119         uint32_t *dscr_p)
 120 {
 121         uint32_t dscr = DSCR_ITE;
 122         uint32_t higher;
 123         int retval;
 124
 125         if (dscr_p)
 126                 dscr = *dscr_p;
 127
 128         /* Wait for DTRRXfull */
 129         long long then = timeval_ms();
 130         while ((dscr & DSCR_DTR_TX_FULL) == 0) {
 131                 retval = mem_ap_read_atomic_u32(armv8->debug_ap,
 132                                 armv8->debug_base + CPUV8_DBG_DSCR,
 133                                 &dscr);
 134                 if (retval != ERROR_OK)
 135                         return retval;
 136                 if (timeval_ms() > then + 1000) {
 137                         LOG_ERROR("Timeout waiting for DTR_TX_FULL, dscr = 0x%08" PRIx32, dscr);
 138                         return ERROR_FAIL;
 139                 }
 140         }
 141
 142         retval = mem_ap_read_atomic_u32(armv8->debug_ap,
 143                                             armv8->debug_base + CPUV8_DBG_DTRTX,
 144                                             (uint32_t *)data);
 145         if (retval != ERROR_OK)
 146                 return retval;
 147
 148         retval = mem_ap_read_atomic_u32(armv8->debug_ap,
 149                                             armv8->debug_base + CPUV8_DBG_DTRRX,
 150                                             &higher);
 151         if (retval != ERROR_OK)
 152                 return retval;
 153
 154         *data = *(uint32_t *)data | (uint64_t)higher << 32;
 155
 156         if (dscr_p)
 157                 *dscr_p = dscr;
 158
 159         return retval;
 160 }
 161
 162 static int dpmv8_dpm_prepare(struct arm_dpm *dpm)
 163 {
 164         struct armv8_common *armv8 = dpm->arm->arch_info;
 165         uint32_t dscr;
 166         int retval;
 167
 168         /* set up invariant:  ITE is set after ever DPM operation */
 169         long long then = timeval_ms();
 170         for (;; ) {
 171                 retval = mem_ap_read_atomic_u32(armv8->debug_ap,
 172                                 armv8->debug_base + CPUV8_DBG_DSCR,
 173                                 &dscr);
 174                 if (retval != ERROR_OK)
 175                         return retval;
 176                 if ((dscr & DSCR_ITE) != 0)
 177                         break;
 178                 if (timeval_ms() > then + 1000) {
 179                         LOG_ERROR("Timeout waiting for dpm prepare");
 180                         return ERROR_FAIL;
 181                 }
 182         }
 183
 184         /* update the stored copy of dscr */
 185         dpm->dscr = dscr;
 186
 187         /* this "should never happen" ... */
 188         if (dscr & DSCR_DTR_RX_FULL) {
 189                 LOG_ERROR("DSCR_DTR_RX_FULL, dscr 0x%08" PRIx32, dscr);
 190                 /* Clear DCCRX */
 191                 retval = mem_ap_read_u32(armv8->debug_ap,
 192                         armv8->debug_base + CPUV8_DBG_DTRRX, &dscr);
 193                 if (retval != ERROR_OK)
 194                         return retval;
 195         }
 196
 197         return retval;
 198 }
 199
 200 static int dpmv8_dpm_finish(struct arm_dpm *dpm)
 201 {
 202         /* REVISIT what could be done here? */
 203         return ERROR_OK;
 204 }
 205
 206 static int dpmv8_exec_opcode(struct arm_dpm *dpm,
 207         uint32_t opcode, uint32_t *p_dscr)
 208 {
 209         struct armv8_common *armv8 = dpm->arm->arch_info;
 210         uint32_t dscr = dpm->dscr;
 211         int retval;
 212
 213         if (p_dscr)
 214                 dscr = *p_dscr;
 215
 216         /* Wait for InstrCompl bit to be set */
 217         long long then = timeval_ms();
 218         while ((dscr & DSCR_ITE) == 0) {
 219                 retval = mem_ap_read_atomic_u32(armv8->debug_ap,
 220                                 armv8->debug_base + CPUV8_DBG_DSCR, &dscr);
 221                 if (retval != ERROR_OK) {
 222                         LOG_ERROR("Could not read DSCR register, opcode = 0x%08" PRIx32, opcode);
 223                         return retval;
 224                 }
 225                 if (timeval_ms() > then + 1000) {
 226                         LOG_ERROR("Timeout waiting for aarch64_exec_opcode");
 227                         return ERROR_FAIL;
 228                 }
 229         }
 230
 231         if (armv8_dpm_get_core_state(dpm) != ARM_STATE_AARCH64)
 232                 opcode = T32_FMTITR(opcode);
 233
 234         retval = mem_ap_write_u32(armv8->debug_ap,
 235                         armv8->debug_base + CPUV8_DBG_ITR, opcode);
 236         if (retval != ERROR_OK)
 237                 return retval;
 238
 239         then = timeval_ms();
 240         do {
 241                 retval = mem_ap_read_atomic_u32(armv8->debug_ap,
 242                                 armv8->debug_base + CPUV8_DBG_DSCR, &dscr);
 243                 if (retval != ERROR_OK) {
 244                         LOG_ERROR("Could not read DSCR register");
 245                         return retval;
 246                 }
 247                 if (timeval_ms() > then + 1000) {
 248                         LOG_ERROR("Timeout waiting for aarch64_exec_opcode");
 249                         return ERROR_FAIL;
 250                 }
 251         } while ((dscr & DSCR_ITE) == 0);       /* Wait for InstrCompl bit to be set */
 252
 253         /* update dscr and el after each command execution */
 254         dpm->dscr = dscr;
 255         if (dpm->last_el != ((dscr >> 8) & 3))
 256                 LOG_DEBUG("EL %i -> %" PRIu32, dpm->last_el, (dscr >> 8) & 3);
 257         dpm->last_el = (dscr >> 8) & 3;
 258
 259         if (dscr & DSCR_ERR) {
 260                 LOG_ERROR("Opcode 0x%08" PRIx32 ", DSCR.ERR=1, DSCR.EL=%i", opcode, dpm->last_el);
 261                 armv8_dpm_handle_exception(dpm, true);
 262                 retval = ERROR_FAIL;
 263         }
 264
 265         if (p_dscr)
 266                 *p_dscr = dscr;
 267
 268         return retval;
 269 }
 270
 271 static int dpmv8_instr_execute(struct arm_dpm *dpm, uint32_t opcode)
 272 {
 273         return dpmv8_exec_opcode(dpm, opcode, NULL);
 274 }
 275
 276 static int dpmv8_instr_write_data_dcc(struct arm_dpm *dpm,
 277         uint32_t opcode, uint32_t data)
 278 {
 279         struct armv8_common *armv8 = dpm->arm->arch_info;
 280         int retval;
 281
 282         retval = dpmv8_write_dcc(armv8, data);
 283         if (retval != ERROR_OK)
 284                 return retval;
 285
 286         return dpmv8_exec_opcode(dpm, opcode, 0);
 287 }
 288
 289 static int dpmv8_instr_write_data_dcc_64(struct arm_dpm *dpm,
 290         uint32_t opcode, uint64_t data)
 291 {
 292         struct armv8_common *armv8 = dpm->arm->arch_info;
 293         int retval;
 294
 295         retval = dpmv8_write_dcc_64(armv8, data);
 296         if (retval != ERROR_OK)
 297                 return retval;
 298
 299         return dpmv8_exec_opcode(dpm, opcode, 0);
 300 }
 301
 302 static int dpmv8_instr_write_data_r0(struct arm_dpm *dpm,
 303         uint32_t opcode, uint32_t data)
 304 {
 305         struct armv8_common *armv8 = dpm->arm->arch_info;
 306         uint32_t dscr = DSCR_ITE;
 307         int retval;
 308
 309         retval = dpmv8_write_dcc(armv8, data);
 310         if (retval != ERROR_OK)
 311                 return retval;
 312
 313         retval = dpmv8_exec_opcode(dpm, armv8_opcode(armv8, READ_REG_DTRRX), &dscr);
 314         if (retval != ERROR_OK)
 315                 return retval;
 316
 317         /* then the opcode, taking data from R0 */
 318         return dpmv8_exec_opcode(dpm, opcode, &dscr);
 319 }
 320
 321 static int dpmv8_instr_write_data_r0_64(struct arm_dpm *dpm,
 322         uint32_t opcode, uint64_t data)
 323 {
 324         struct armv8_common *armv8 = dpm->arm->arch_info;
 325         int retval;
 326
 327         if (dpm->arm->core_state != ARM_STATE_AARCH64)
 328                 return dpmv8_instr_write_data_r0(dpm, opcode, data);
 329
 330         /* transfer data from DCC to R0 */
 331         retval = dpmv8_write_dcc_64(armv8, data);
 332         if (retval == ERROR_OK)
 333                 retval = dpmv8_exec_opcode(dpm, ARMV8_MRS(SYSTEM_DBG_DBGDTR_EL0, 0), &dpm->dscr);
 334
 335         /* then the opcode, taking data from R0 */
 336         if (retval == ERROR_OK)
 337                 retval = dpmv8_exec_opcode(dpm, opcode, &dpm->dscr);
 338
 339         return retval;
 340 }
 341
 342 static int dpmv8_instr_cpsr_sync(struct arm_dpm *dpm)
 343 {
 344         int retval;
 345         struct armv8_common *armv8 = dpm->arm->arch_info;
 346
 347         /* "Prefetch flush" after modifying execution status in CPSR */
 348         retval = dpmv8_exec_opcode(dpm, armv8_opcode(armv8, ARMV8_OPC_DSB_SY), &dpm->dscr);
 349         if (retval == ERROR_OK)
 350                 dpmv8_exec_opcode(dpm, armv8_opcode(armv8, ARMV8_OPC_ISB_SY), &dpm->dscr);
 351         return retval;
 352 }
 353
 354 static int dpmv8_instr_read_data_dcc(struct arm_dpm *dpm,
 355         uint32_t opcode, uint32_t *data)
 356 {
 357         struct armv8_common *armv8 = dpm->arm->arch_info;
 358         int retval;
 359
 360         /* the opcode, writing data to DCC */
 361         retval = dpmv8_exec_opcode(dpm, opcode, &dpm->dscr);
 362         if (retval != ERROR_OK)
 363                 return retval;
 364
 365         return dpmv8_read_dcc(armv8, data, &dpm->dscr);
 366 }
 367
 368 static int dpmv8_instr_read_data_dcc_64(struct arm_dpm *dpm,
 369         uint32_t opcode, uint64_t *data)
 370 {
 371         struct armv8_common *armv8 = dpm->arm->arch_info;
 372         int retval;
 373
 374         /* the opcode, writing data to DCC */
 375         retval = dpmv8_exec_opcode(dpm, opcode, &dpm->dscr);
 376         if (retval != ERROR_OK)
 377                 return retval;
 378
 379         return dpmv8_read_dcc_64(armv8, data, &dpm->dscr);
 380 }
 381
 382 static int dpmv8_instr_read_data_r0(struct arm_dpm *dpm,
 383         uint32_t opcode, uint32_t *data)
 384 {
 385         struct armv8_common *armv8 = dpm->arm->arch_info;
 386         int retval;
 387
 388         /* the opcode, writing data to R0 */
 389         retval = dpmv8_exec_opcode(dpm, opcode, &dpm->dscr);
 390         if (retval != ERROR_OK)
 391                 return retval;
 392
 393         /* write R0 to DCC */
 394         retval = dpmv8_exec_opcode(dpm, armv8_opcode(armv8, WRITE_REG_DTRTX), &dpm->dscr);
 395         if (retval != ERROR_OK)
 396                 return retval;
 397
 398         return dpmv8_read_dcc(armv8, data, &dpm->dscr);
 399 }
 400
 401 static int dpmv8_instr_read_data_r0_64(struct arm_dpm *dpm,
 402         uint32_t opcode, uint64_t *data)
 403 {
 404         struct armv8_common *armv8 = dpm->arm->arch_info;
 405         int retval;
 406
 407         if (dpm->arm->core_state != ARM_STATE_AARCH64) {
 408                 uint32_t tmp;
 409                 retval = dpmv8_instr_read_data_r0(dpm, opcode, &tmp);
 410                 if (retval == ERROR_OK)
 411                         *data = tmp;
 412                 return retval;
 413         }
 414
 415         /* the opcode, writing data to R0 */
 416         retval = dpmv8_exec_opcode(dpm, opcode, &dpm->dscr);
 417         if (retval != ERROR_OK)
 418                 return retval;
 419
 420         /* write R0 to DCC */
 421         retval = dpmv8_exec_opcode(dpm, ARMV8_MSR_GP(SYSTEM_DBG_DBGDTR_EL0, 0), &dpm->dscr);
 422         if (retval != ERROR_OK)
 423                 return retval;
 424
 425         return dpmv8_read_dcc_64(armv8, data, &dpm->dscr);
 426 }
 427
 428 #if 0
 429 static int dpmv8_bpwp_enable(struct arm_dpm *dpm, unsigned index_t,
 430         target_addr_t addr, uint32_t control)
 431 {
 432         struct armv8_common *armv8 = dpm->arm->arch_info;
 433         uint32_t vr = armv8->debug_base;
 434         uint32_t cr = armv8->debug_base;
 435         int retval;
 436
 437         switch (index_t) {
 438                 case 0 ... 15:  /* breakpoints */
 439                         vr += CPUV8_DBG_BVR_BASE;
 440                         cr += CPUV8_DBG_BCR_BASE;
 441                         break;
 442                 case 16 ... 31: /* watchpoints */
 443                         vr += CPUV8_DBG_WVR_BASE;
 444                         cr += CPUV8_DBG_WCR_BASE;
 445                         index_t -= 16;
 446                         break;
 447                 default:
 448                         return ERROR_FAIL;
 449         }
 450         vr += 16 * index_t;
 451         cr += 16 * index_t;
 452
 453         LOG_DEBUG("A8: bpwp enable, vr %08x cr %08x",
 454                 (unsigned) vr, (unsigned) cr);
 455
 456         retval = mem_ap_write_atomic_u32(armv8->debug_ap, vr, addr);
 457         if (retval != ERROR_OK)
 458                 return retval;
 459         return mem_ap_write_atomic_u32(armv8->debug_ap, cr, control);
 460 }
 461 #endif
 462
 463 static int dpmv8_bpwp_disable(struct arm_dpm *dpm, unsigned index_t)
 464 {
 465         struct armv8_common *armv8 = dpm->arm->arch_info;
 466         uint32_t cr;
 467
 468         switch (index_t) {
 469                 case 0 ... 15:
 470                         cr = armv8->debug_base + CPUV8_DBG_BCR_BASE;
 471                         break;
 472                 case 16 ... 31:
 473                         cr = armv8->debug_base + CPUV8_DBG_WCR_BASE;
 474                         index_t -= 16;
 475                         break;
 476                 default:
 477                         return ERROR_FAIL;
 478         }
 479         cr += 16 * index_t;
 480
 481         LOG_DEBUG("A: bpwp disable, cr %08x", (unsigned) cr);
 482
 483         /* clear control register */
 484         return mem_ap_write_atomic_u32(armv8->debug_ap, cr, 0);
 485 }
 486
 487 /*
 488  * Coprocessor support
 489  */
 490
 491 /* Read coprocessor */
 492 static int dpmv8_mrc(struct target *target, int cpnum,
 493         uint32_t op1, uint32_t op2, uint32_t CRn, uint32_t CRm,
 494         uint32_t *value)
 495 {
 496         struct arm *arm = target_to_arm(target);
 497         struct arm_dpm *dpm = arm->dpm;
 498         int retval;
 499
 500         retval = dpm->prepare(dpm);
 501         if (retval != ERROR_OK)
 502                 return retval;
 503
 504         LOG_DEBUG("MRC p%d, %d, r0, c%d, c%d, %d", cpnum,
 505                 (int) op1, (int) CRn,
 506                 (int) CRm, (int) op2);
 507
 508         /* read coprocessor register into R0; return via DCC */
 509         retval = dpm->instr_read_data_r0(dpm,
 510                         ARMV4_5_MRC(cpnum, op1, 0, CRn, CRm, op2),
 511                         value);
 512
 513         /* (void) */ dpm->finish(dpm);
 514         return retval;
 515 }
 516
 517 static int dpmv8_mcr(struct target *target, int cpnum,
 518         uint32_t op1, uint32_t op2, uint32_t CRn, uint32_t CRm,
 519         uint32_t value)
 520 {
 521         struct arm *arm = target_to_arm(target);
 522         struct arm_dpm *dpm = arm->dpm;
 523         int retval;
 524
 525         retval = dpm->prepare(dpm);
 526         if (retval != ERROR_OK)
 527                 return retval;
 528
 529         LOG_DEBUG("MCR p%d, %d, r0, c%d, c%d, %d", cpnum,
 530                 (int) op1, (int) CRn,
 531                 (int) CRm, (int) op2);
 532
 533         /* read DCC into r0; then write coprocessor register from R0 */
 534         retval = dpm->instr_write_data_r0(dpm,
 535                         ARMV4_5_MCR(cpnum, op1, 0, CRn, CRm, op2),
 536                         value);
 537
 538         /* (void) */ dpm->finish(dpm);
 539         return retval;
 540 }
 541
 542 /*----------------------------------------------------------------------*/
 543
 544 /*
 545  * Register access utilities
 546  */
 547
 548 int armv8_dpm_modeswitch(struct arm_dpm *dpm, enum arm_mode mode)
 549 {
 550         struct armv8_common *armv8 = (struct armv8_common *)dpm->arm->arch_info;
 551         int retval = ERROR_OK;
 552         unsigned int target_el;
 553         enum arm_state core_state;
 554         uint32_t cpsr;
 555
 556         /* restore previous mode */
 557         if (mode == ARM_MODE_ANY) {
 558                 cpsr = buf_get_u32(dpm->arm->cpsr->value, 0, 32);
 559
 560                 LOG_DEBUG("restoring mode, cpsr = 0x%08"PRIx32, cpsr);
 561
 562         } else {
 563                 LOG_DEBUG("setting mode 0x%x", mode);
 564                 cpsr = mode;
 565         }
 566
 567         switch (cpsr & 0x1f) {
 568         /* aarch32 modes */
 569         case ARM_MODE_USR:
 570                 target_el = 0;
 571                 break;
 572         case ARM_MODE_SVC:
 573         case ARM_MODE_ABT:
 574         case ARM_MODE_IRQ:
 575         case ARM_MODE_FIQ:
 576         case ARM_MODE_SYS:
 577                 target_el = 1;
 578                 break;
 579         /*
 580          * TODO: handle ARM_MODE_HYP
 581          * case ARM_MODE_HYP:
 582          *      target_el = 2;
 583          *      break;
 584          */
 585         case ARM_MODE_MON:
 586                 target_el = 3;
 587                 break;
 588         /* aarch64 modes */
 589         default:
 590                 target_el = (cpsr >> 2) & 3;
 591         }
 592
 593         if (target_el > SYSTEM_CUREL_EL3) {
 594                 LOG_ERROR("%s: Invalid target exception level %i", __func__, target_el);
 595                 return ERROR_FAIL;
 596         }
 597
 598         LOG_DEBUG("target_el = %i, last_el = %i", target_el, dpm->last_el);
 599         if (target_el > dpm->last_el) {
 600                 retval = dpm->instr_execute(dpm,
 601                                 armv8_opcode(armv8, ARMV8_OPC_DCPS) | target_el);
 602
 603                 /* DCPS clobbers registers just like an exception taken */
 604                 armv8_dpm_handle_exception(dpm, false);
 605         } else {
 606                 core_state = armv8_dpm_get_core_state(dpm);
 607                 if (core_state != ARM_STATE_AARCH64) {
 608                         /* cannot do DRPS/ERET when already in EL0 */
 609                         if (dpm->last_el != 0) {
 610                                 /* load SPSR with the desired mode and execute DRPS */
 611                                 LOG_DEBUG("SPSR = 0x%08"PRIx32, cpsr);
 612                                 retval = dpm->instr_write_data_r0(dpm,
 613                                                 ARMV8_MSR_GP_xPSR_T1(1, 0, 15), cpsr);
 614                                 if (retval == ERROR_OK)
 615                                         retval = dpm->instr_execute(dpm, armv8_opcode(armv8, ARMV8_OPC_DRPS));
 616                         }
 617                 } else {
 618                         /*
 619                          * need to execute multiple DRPS instructions until target_el
 620                          * is reached
 621                          */
 622                         while (retval == ERROR_OK && dpm->last_el != target_el) {
 623                                 unsigned int cur_el = dpm->last_el;
 624                                 retval = dpm->instr_execute(dpm, armv8_opcode(armv8, ARMV8_OPC_DRPS));
 625                                 if (cur_el == dpm->last_el) {
 626                                         LOG_INFO("Cannot reach EL %i, SPSR corrupted?", target_el);
 627                                         break;
 628                                 }
 629                         }
 630                 }
 631
 632                 /* On executing DRPS, DSPSR and DLR become UNKNOWN, mark them as dirty */
 633                 dpm->arm->cpsr->dirty = true;
 634                 dpm->arm->pc->dirty = true;
 635
 636                 /*
 637                  * re-evaluate the core state, we might be in Aarch32 state now
 638                  * we rely on dpm->dscr being up-to-date
 639                  */
 640                 core_state = armv8_dpm_get_core_state(dpm);
 641                 armv8_select_opcodes(armv8, core_state == ARM_STATE_AARCH64);
 642                 armv8_select_reg_access(armv8, core_state == ARM_STATE_AARCH64);
 643         }
 644
 645         return retval;
 646 }
 647
 648 /*
 649  * Common register read, relies on armv8_select_reg_access() having been called.
 650  */
 651 static int dpmv8_read_reg(struct arm_dpm *dpm, struct reg *r, unsigned regnum)
 652 {
 653         struct armv8_common *armv8 = dpm->arm->arch_info;
 654         int retval = ERROR_FAIL;
 655
 656         if (r->size <= 64) {
 657                 uint64_t value_64;
 658                 retval = armv8->read_reg_u64(armv8, regnum, &value_64);
 659
 660                 if (retval == ERROR_OK) {
 661                         r->valid = true;
 662                         r->dirty = false;
 663                         buf_set_u64(r->value, 0, r->size, value_64);
 664                         if (r->size == 64)
 665                                 LOG_DEBUG("READ: %s, %16.8llx", r->name, (unsigned long long) value_64);
 666                         else
 667                                 LOG_DEBUG("READ: %s, %8.8x", r->name, (unsigned int) value_64);
 668                 }
 669         } else if (r->size <= 128) {
 670                 uint64_t lvalue = 0, hvalue = 0;
 671                 retval = armv8->read_reg_u128(armv8, regnum, &lvalue, &hvalue);
 672
 673                 if (retval == ERROR_OK) {
 674                         r->valid = true;
 675                         r->dirty = false;
 676
 677                         buf_set_u64(r->value, 0, 64, lvalue);
 678                         buf_set_u64(r->value + 8, 0, r->size - 64, hvalue);
 679
 680                         LOG_DEBUG("READ: %s, lvalue=%16.8llx", r->name, (unsigned long long) lvalue);
 681                         LOG_DEBUG("READ: %s, hvalue=%16.8llx", r->name, (unsigned long long) hvalue);
 682                 }
 683         }
 684
 685         if (retval != ERROR_OK)
 686                 LOG_ERROR("Failed to read %s register", r->name);
 687
 688         return retval;
 689 }
 690
 691 /*
 692  * Common register write, relies on armv8_select_reg_access() having been called.
 693  */
 694 static int dpmv8_write_reg(struct arm_dpm *dpm, struct reg *r, unsigned regnum)
 695 {
 696         struct armv8_common *armv8 = dpm->arm->arch_info;
 697         int retval = ERROR_FAIL;
 698
 699         if (r->size <= 64) {
 700                 uint64_t value_64;
 701
 702                 value_64 = buf_get_u64(r->value, 0, r->size);
 703                 retval = armv8->write_reg_u64(armv8, regnum, value_64);
 704
 705                 if (retval == ERROR_OK) {
 706                         r->dirty = false;
 707                         if (r->size == 64)
 708                                 LOG_DEBUG("WRITE: %s, %16.8llx", r->name, (unsigned long long)value_64);
 709                         else
 710                                 LOG_DEBUG("WRITE: %s, %8.8x", r->name, (unsigned int)value_64);
 711                 }
 712         } else if (r->size <= 128) {
 713                 uint64_t lvalue, hvalue;
 714
 715                 lvalue = buf_get_u64(r->value, 0, 64);
 716                 hvalue = buf_get_u64(r->value + 8, 0, r->size - 64);
 717                 retval = armv8->write_reg_u128(armv8, regnum, lvalue, hvalue);
 718
 719                 if (retval == ERROR_OK) {
 720                         r->dirty = false;
 721
 722                         LOG_DEBUG("WRITE: %s, lvalue=%16.8llx", r->name, (unsigned long long) lvalue);
 723                         LOG_DEBUG("WRITE: %s, hvalue=%16.8llx", r->name, (unsigned long long) hvalue);
 724                 }
 725         }
 726
 727         if (retval != ERROR_OK)
 728                 LOG_ERROR("Failed to write %s register", r->name);
 729
 730         return retval;
 731 }
 732
 733 /**
 734  * Read basic registers of the current context:  R0 to R15, and CPSR;
 735  * sets the core mode (such as USR or IRQ) and state (such as ARM or Thumb).
 736  * In normal operation this is called on entry to halting debug state,
 737  * possibly after some other operations supporting restore of debug state
 738  * or making sure the CPU is fully idle (drain write buffer, etc).
 739  */
 740 int armv8_dpm_read_current_registers(struct arm_dpm *dpm)
 741 {
 742         struct arm *arm = dpm->arm;
 743         struct armv8_common *armv8 = (struct armv8_common *)arm->arch_info;
 744         struct reg_cache *cache;
 745         struct reg *r;
 746         uint32_t cpsr;
 747         int retval;
 748
 749         retval = dpm->prepare(dpm);
 750         if (retval != ERROR_OK)
 751                 return retval;
 752
 753         cache = arm->core_cache;
 754
 755         /* read R0 first (it's used for scratch), then CPSR */
 756         r = cache->reg_list + ARMV8_R0;
 757         if (!r->valid) {
 758                 retval = dpmv8_read_reg(dpm, r, ARMV8_R0);
 759                 if (retval != ERROR_OK)
 760                         goto fail;
 761         }
 762         r->dirty = true;
 763
 764         /* read R1, too, it will be clobbered during memory access */
 765         r = cache->reg_list + ARMV8_R1;
 766         if (!r->valid) {
 767                 retval = dpmv8_read_reg(dpm, r, ARMV8_R1);
 768                 if (retval != ERROR_OK)
 769                         goto fail;
 770         }
 771
 772         /* read cpsr to r0 and get it back */
 773         retval = dpm->instr_read_data_r0(dpm,
 774                         armv8_opcode(armv8, READ_REG_DSPSR), &cpsr);
 775         if (retval != ERROR_OK)
 776                 goto fail;
 777
 778         /* update core mode and state */
 779         armv8_set_cpsr(arm, cpsr);
 780
 781         for (unsigned int i = ARMV8_PC; i < cache->num_regs ; i++) {
 782                 struct arm_reg *arm_reg;
 783
 784                 r = armv8_reg_current(arm, i);
 785                 if (!r->exist || r->valid)
 786                         continue;
 787
 788                 /* Skip reading FP-SIMD registers */
 789                 if (r->number >= ARMV8_V0 && r->number <= ARMV8_FPCR)
 790                         continue;
 791
 792                 /*
 793                  * Only read registers that are available from the
 794                  * current EL (or core mode).
 795                  */
 796                 arm_reg = r->arch_info;
 797                 if (arm_reg->mode != ARM_MODE_ANY &&
 798                                 dpm->last_el != armv8_curel_from_core_mode(arm_reg->mode))
 799                         continue;
 800
 801                 /* Special case: ARM_MODE_SYS has no SPSR at EL1 */
 802                 if (r->number == ARMV8_SPSR_EL1 && arm->core_mode == ARM_MODE_SYS)
 803                         continue;
 804
 805                 retval = dpmv8_read_reg(dpm, r, i);
 806                 if (retval != ERROR_OK)
 807                         goto fail;
 808
 809         }
 810
 811 fail:
 812         dpm->finish(dpm);
 813         return retval;
 814 }
 815
 816 /* Avoid needless I/O ... leave breakpoints and watchpoints alone
 817  * unless they're removed, or need updating because of single-stepping
 818  * or running debugger code.
 819  */
 820 static int dpmv8_maybe_update_bpwp(struct arm_dpm *dpm, bool bpwp,
 821         struct dpm_bpwp *xp, int *set_p)
 822 {
 823         int retval = ERROR_OK;
 824         bool disable;
 825
 826         if (!set_p) {
 827                 if (!xp->dirty)
 828                         goto done;
 829                 xp->dirty = false;
 830                 /* removed or startup; we must disable it */
 831                 disable = true;
 832         } else if (bpwp) {
 833                 if (!xp->dirty)
 834                         goto done;
 835                 /* disabled, but we must set it */
 836                 xp->dirty = disable = false;
 837                 *set_p = true;
 838         } else {
 839                 if (!*set_p)
 840                         goto done;
 841                 /* set, but we must temporarily disable it */
 842                 xp->dirty = disable = true;
 843                 *set_p = false;
 844         }
 845
 846         if (disable)
 847                 retval = dpm->bpwp_disable(dpm, xp->number);
 848         else
 849                 retval = dpm->bpwp_enable(dpm, xp->number,
 850                                 xp->address, xp->control);
 851
 852         if (retval != ERROR_OK)
 853                 LOG_ERROR("%s: can't %s HW %spoint %d",
 854                         disable ? "disable" : "enable",
 855                         target_name(dpm->arm->target),
 856                         (xp->number < 16) ? "break" : "watch",
 857                         xp->number & 0xf);
 858 done:
 859         return retval;
 860 }
 861
 862 static int dpmv8_add_breakpoint(struct target *target, struct breakpoint *bp);
 863
 864 /**
 865  * Writes all modified core registers for all processor modes.  In normal
 866  * operation this is called on exit from halting debug state.
 867  *
 868  * @param dpm: represents the processor
 869  * @param bpwp: true ensures breakpoints and watchpoints are set,
 870  *      false ensures they are cleared
 871  */
 872 int armv8_dpm_write_dirty_registers(struct arm_dpm *dpm, bool bpwp)
 873 {
 874         struct arm *arm = dpm->arm;
 875         struct reg_cache *cache = arm->core_cache;
 876         int retval;
 877
 878         retval = dpm->prepare(dpm);
 879         if (retval != ERROR_OK)
 880                 goto done;
 881
 882         /* If we're managing hardware breakpoints for this core, enable
 883          * or disable them as requested.
 884          *
 885          * REVISIT We don't yet manage them for ANY cores.  Eventually
 886          * we should be able to assume we handle them; but until then,
 887          * cope with the hand-crafted breakpoint code.
 888          */
 889         if (arm->target->type->add_breakpoint == dpmv8_add_breakpoint) {
 890                 for (unsigned i = 0; i < dpm->nbp; i++) {
 891                         struct dpm_bp *dbp = dpm->dbp + i;
 892                         struct breakpoint *bp = dbp->bp;
 893
 894                         retval = dpmv8_maybe_update_bpwp(dpm, bpwp, &dbp->bpwp,
 895                                         bp ? &bp->set : NULL);
 896                         if (retval != ERROR_OK)
 897                                 goto done;
 898                 }
 899         }
 900
 901         /* enable/disable watchpoints */
 902         for (unsigned i = 0; i < dpm->nwp; i++) {
 903                 struct dpm_wp *dwp = dpm->dwp + i;
 904                 struct watchpoint *wp = dwp->wp;
 905
 906                 retval = dpmv8_maybe_update_bpwp(dpm, bpwp, &dwp->bpwp,
 907                                 wp ? &wp->set : NULL);
 908                 if (retval != ERROR_OK)
 909                         goto done;
 910         }
 911
 912         /* NOTE:  writes to breakpoint and watchpoint registers might
 913          * be queued, and need (efficient/batched) flushing later.
 914          */
 915
 916         /* Restore original core mode and state */
 917         retval = armv8_dpm_modeswitch(dpm, ARM_MODE_ANY);
 918         if (retval != ERROR_OK)
 919                 goto done;
 920
 921         /* check everything except our scratch register R0 */
 922         for (unsigned i = 1; i < cache->num_regs; i++) {
 923                 struct arm_reg *r;
 924
 925                 /* skip non-existent */
 926                 if (!cache->reg_list[i].exist)
 927                         continue;
 928                 /* skip PC and CPSR */
 929                 if (i == ARMV8_PC || i == ARMV8_xPSR)
 930                         continue;
 931                 /* skip invalid */
 932                 if (!cache->reg_list[i].valid)
 933                         continue;
 934                 /* skip non-dirty */
 935                 if (!cache->reg_list[i].dirty)
 936                         continue;
 937
 938                 /* skip all registers not on the current EL */
 939                 r = cache->reg_list[i].arch_info;
 940                 if (r->mode != ARM_MODE_ANY &&
 941                                 dpm->last_el != armv8_curel_from_core_mode(r->mode))
 942                         continue;
 943
 944                 retval = dpmv8_write_reg(dpm, &cache->reg_list[i], i);
 945                 if (retval != ERROR_OK)
 946                         break;
 947         }
 948
 949         /* flush CPSR and PC */
 950         if (retval == ERROR_OK)
 951                 retval = dpmv8_write_reg(dpm, &cache->reg_list[ARMV8_xPSR], ARMV8_xPSR);
 952         if (retval == ERROR_OK)
 953                 retval = dpmv8_write_reg(dpm, &cache->reg_list[ARMV8_PC], ARMV8_PC);
 954         /* flush R0 -- it's *very* dirty by now */
 955         if (retval == ERROR_OK)
 956                 retval = dpmv8_write_reg(dpm, &cache->reg_list[0], 0);
 957         if (retval == ERROR_OK)
 958                 dpm->instr_cpsr_sync(dpm);
 959 done:
 960         dpm->finish(dpm);
 961         return retval;
 962 }
 963
 964 /*
 965  * Standard ARM register accessors ... there are three methods
 966  * in "struct arm", to support individual read/write and bulk read
 967  * of registers.
 968  */
 969
 970 static int armv8_dpm_read_core_reg(struct target *target, struct reg *r,
 971         int regnum, enum arm_mode mode)
 972 {
 973         struct arm *arm = target_to_arm(target);
 974         struct arm_dpm *dpm = target_to_arm(target)->dpm;
 975         int retval;
 976         int max = arm->core_cache->num_regs;
 977
 978         if (regnum < 0 || regnum >= max)
 979                 return ERROR_COMMAND_SYNTAX_ERROR;
 980
 981         /*
 982          * REVISIT what happens if we try to read SPSR in a core mode
 983          * which has no such register?
 984          */
 985         retval = dpm->prepare(dpm);
 986         if (retval != ERROR_OK)
 987                 return retval;
 988
 989         retval = dpmv8_read_reg(dpm, r, regnum);
 990         if (retval != ERROR_OK)
 991                 goto fail;
 992
 993 fail:
 994         /* (void) */ dpm->finish(dpm);
 995         return retval;
 996 }
 997
 998 static int armv8_dpm_write_core_reg(struct target *target, struct reg *r,
 999         int regnum, enum arm_mode mode, uint8_t *value)
1000 {
1001         struct arm *arm = target_to_arm(target);
1002         struct arm_dpm *dpm = target_to_arm(target)->dpm;
1003         int retval;
1004         int max = arm->core_cache->num_regs;
1005
1006         if (regnum < 0 || regnum > max)
1007                 return ERROR_COMMAND_SYNTAX_ERROR;
1008
1009         /* REVISIT what happens if we try to write SPSR in a core mode
1010          * which has no such register?
1011          */
1012
1013         retval = dpm->prepare(dpm);
1014         if (retval != ERROR_OK)
1015                 return retval;
1016
1017         retval = dpmv8_write_reg(dpm, r, regnum);
1018
1019         /* always clean up, regardless of error */
1020         dpm->finish(dpm);
1021
1022         return retval;
1023 }
1024
1025 static int armv8_dpm_full_context(struct target *target)
1026 {
1027         struct arm *arm = target_to_arm(target);
1028         struct arm_dpm *dpm = arm->dpm;
1029         struct reg_cache *cache = arm->core_cache;
1030         int retval;
1031         bool did_read;
1032
1033         retval = dpm->prepare(dpm);
1034         if (retval != ERROR_OK)
1035                 goto done;
1036
1037         do {
1038                 enum arm_mode mode = ARM_MODE_ANY;
1039
1040                 did_read = false;
1041
1042                 /* We "know" arm_dpm_read_current_registers() was called so
1043                  * the unmapped registers (R0..R7, PC, AND CPSR) and some
1044                  * view of R8..R14 are current.  We also "know" oddities of
1045                  * register mapping: special cases for R8..R12 and SPSR.
1046                  *
1047                  * Pick some mode with unread registers and read them all.
1048                  * Repeat until done.
1049                  */
1050                 for (unsigned i = 0; i < cache->num_regs; i++) {
1051                         struct arm_reg *r;
1052
1053                         if (!cache->reg_list[i].exist || cache->reg_list[i].valid)
1054                                 continue;
1055                         r = cache->reg_list[i].arch_info;
1056
1057                         /* may need to pick a mode and set CPSR */
1058                         if (!did_read) {
1059                                 did_read = true;
1060                                 mode = r->mode;
1061
1062                                 /* For regular (ARM_MODE_ANY) R8..R12
1063                                  * in case we've entered debug state
1064                                  * in FIQ mode we need to patch mode.
1065                                  */
1066                                 if (mode != ARM_MODE_ANY)
1067                                         retval = armv8_dpm_modeswitch(dpm, mode);
1068                                 else
1069                                         retval = armv8_dpm_modeswitch(dpm, ARM_MODE_USR);
1070
1071                                 if (retval != ERROR_OK)
1072                                         goto done;
1073                         }
1074                         if (r->mode != mode)
1075                                 continue;
1076
1077                         /* CPSR was read, so "R16" must mean SPSR */
1078                         retval = dpmv8_read_reg(dpm,
1079                                         &cache->reg_list[i],
1080                                         (r->num == 16) ? 17 : r->num);
1081                         if (retval != ERROR_OK)
1082                                 goto done;
1083                 }
1084
1085         } while (did_read);
1086
1087         retval = armv8_dpm_modeswitch(dpm, ARM_MODE_ANY);
1088         /* (void) */ dpm->finish(dpm);
1089 done:
1090         return retval;
1091 }
1092
1093
1094 /*----------------------------------------------------------------------*/
1095
1096 /*
1097  * Breakpoint and Watchpoint support.
1098  *
1099  * Hardware {break,watch}points are usually left active, to minimize
1100  * debug entry/exit costs.  When they are set or cleared, it's done in
1101  * batches.  Also, DPM-conformant hardware can update debug registers
1102  * regardless of whether the CPU is running or halted ... though that
1103  * fact isn't currently leveraged.
1104  */
1105
1106 static int dpmv8_bpwp_setup(struct arm_dpm *dpm, struct dpm_bpwp *xp,
1107         uint32_t addr, uint32_t length)
1108 {
1109         uint32_t control;
1110
1111         control = (1 << 0)      /* enable */
1112                 | (3 << 1);     /* both user and privileged access */
1113
1114         /* Match 1, 2, or all 4 byte addresses in this word.
1115          *
1116          * FIXME:  v7 hardware allows lengths up to 2 GB for BP and WP.
1117          * Support larger length, when addr is suitably aligned.  In
1118          * particular, allow watchpoints on 8 byte "double" values.
1119          *
1120          * REVISIT allow watchpoints on unaligned 2-bit values; and on
1121          * v7 hardware, unaligned 4-byte ones too.
1122          */
1123         switch (length) {
1124                 case 1:
1125                         control |= (1 << (addr & 3)) << 5;
1126                         break;
1127                 case 2:
1128                         /* require 2-byte alignment */
1129                         if (!(addr & 1)) {
1130                                 control |= (3 << (addr & 2)) << 5;
1131                                 break;
1132                         }
1133                 /* FALL THROUGH */
1134                 case 4:
1135                         /* require 4-byte alignment */
1136                         if (!(addr & 3)) {
1137                                 control |= 0xf << 5;
1138                                 break;
1139                         }
1140                 /* FALL THROUGH */
1141                 default:
1142                         LOG_ERROR("unsupported {break,watch}point length/alignment");
1143                         return ERROR_COMMAND_SYNTAX_ERROR;
1144         }
1145
1146         /* other shared control bits:
1147          * bits 15:14 == 0 ... both secure and nonsecure states (v6.1+ only)
1148          * bit 20 == 0 ... not linked to a context ID
1149          * bit 28:24 == 0 ... not ignoring N LSBs (v7 only)
1150          */
1151
1152         xp->address = addr & ~3;
1153         xp->control = control;
1154         xp->dirty = true;
1155
1156         LOG_DEBUG("BPWP: addr %8.8" PRIx32 ", control %" PRIx32 ", number %d",
1157                 xp->address, control, xp->number);
1158
1159         /* hardware is updated in write_dirty_registers() */
1160         return ERROR_OK;
1161 }
1162
1163 static int dpmv8_add_breakpoint(struct target *target, struct breakpoint *bp)
1164 {
1165         struct arm *arm = target_to_arm(target);
1166         struct arm_dpm *dpm = arm->dpm;
1167         int retval = ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
1168
1169         if (bp->length < 2)
1170                 return ERROR_COMMAND_SYNTAX_ERROR;
1171         if (!dpm->bpwp_enable)
1172                 return retval;
1173
1174         /* FIXME we need a generic solution for software breakpoints. */
1175         if (bp->type == BKPT_SOFT)
1176                 LOG_DEBUG("using HW bkpt, not SW...");
1177
1178         for (unsigned i = 0; i < dpm->nbp; i++) {
1179                 if (!dpm->dbp[i].bp) {
1180                         retval = dpmv8_bpwp_setup(dpm, &dpm->dbp[i].bpwp,
1181                                         bp->address, bp->length);
1182                         if (retval == ERROR_OK)
1183                                 dpm->dbp[i].bp = bp;
1184                         break;
1185                 }
1186         }
1187
1188         return retval;
1189 }
1190
1191 static int dpmv8_remove_breakpoint(struct target *target, struct breakpoint *bp)
1192 {
1193         struct arm *arm = target_to_arm(target);
1194         struct arm_dpm *dpm = arm->dpm;
1195         int retval = ERROR_COMMAND_SYNTAX_ERROR;
1196
1197         for (unsigned i = 0; i < dpm->nbp; i++) {
1198                 if (dpm->dbp[i].bp == bp) {
1199                         dpm->dbp[i].bp = NULL;
1200                         dpm->dbp[i].bpwp.dirty = true;
1201
1202                         /* hardware is updated in write_dirty_registers() */
1203                         retval = ERROR_OK;
1204                         break;
1205                 }
1206         }
1207
1208         return retval;
1209 }
1210
1211 static int dpmv8_watchpoint_setup(struct arm_dpm *dpm, unsigned index_t,
1212         struct watchpoint *wp)
1213 {
1214         int retval;
1215         struct dpm_wp *dwp = dpm->dwp + index_t;
1216         uint32_t control;
1217
1218         /* this hardware doesn't support data value matching or masking */
1219         if (wp->value || wp->mask != ~(uint32_t)0) {
1220                 LOG_DEBUG("watchpoint values and masking not supported");
1221                 return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
1222         }
1223
1224         retval = dpmv8_bpwp_setup(dpm, &dwp->bpwp, wp->address, wp->length);
1225         if (retval != ERROR_OK)
1226                 return retval;
1227
1228         control = dwp->bpwp.control;
1229         switch (wp->rw) {
1230                 case WPT_READ:
1231                         control |= 1 << 3;
1232                         break;
1233                 case WPT_WRITE:
1234                         control |= 2 << 3;
1235                         break;
1236                 case WPT_ACCESS:
1237                         control |= 3 << 3;
1238                         break;
1239         }
1240         dwp->bpwp.control = control;
1241
1242         dpm->dwp[index_t].wp = wp;
1243
1244         return retval;
1245 }
1246
1247 static int dpmv8_add_watchpoint(struct target *target, struct watchpoint *wp)
1248 {
1249         struct arm *arm = target_to_arm(target);
1250         struct arm_dpm *dpm = arm->dpm;
1251         int retval = ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
1252
1253         if (dpm->bpwp_enable) {
1254                 for (unsigned i = 0; i < dpm->nwp; i++) {
1255                         if (!dpm->dwp[i].wp) {
1256                                 retval = dpmv8_watchpoint_setup(dpm, i, wp);
1257                                 break;
1258                         }
1259                 }
1260         }
1261
1262         return retval;
1263 }
1264
1265 static int dpmv8_remove_watchpoint(struct target *target, struct watchpoint *wp)
1266 {
1267         struct arm *arm = target_to_arm(target);
1268         struct arm_dpm *dpm = arm->dpm;
1269         int retval = ERROR_COMMAND_SYNTAX_ERROR;
1270
1271         for (unsigned i = 0; i < dpm->nwp; i++) {
1272                 if (dpm->dwp[i].wp == wp) {
1273                         dpm->dwp[i].wp = NULL;
1274                         dpm->dwp[i].bpwp.dirty = true;
1275
1276                         /* hardware is updated in write_dirty_registers() */
1277                         retval = ERROR_OK;
1278                         break;
1279                 }
1280         }
1281
1282         return retval;
1283 }
1284
1285 /*
1286  * Handle exceptions taken in debug state. This happens mostly for memory
1287  * accesses that violated a MMU policy. Taking an exception while in debug
1288  * state clobbers certain state registers on the target exception level.
1289  * Just mark those registers dirty so that they get restored on resume.
1290  * This works both for Aarch32 and Aarch64 states.
1291  *
1292  * This function must not perform any actions that trigger another exception
1293  * or a recursion will happen.
1294  */
1295 void armv8_dpm_handle_exception(struct arm_dpm *dpm, bool do_restore)
1296 {
1297         struct armv8_common *armv8 = dpm->arm->arch_info;
1298         struct reg_cache *cache = dpm->arm->core_cache;
1299         enum arm_state core_state;
1300         uint64_t dlr;
1301         uint32_t dspsr;
1302         unsigned int el;
1303
1304         static const int clobbered_regs_by_el[3][5] = {
1305                 { ARMV8_PC, ARMV8_xPSR, ARMV8_ELR_EL1, ARMV8_ESR_EL1, ARMV8_SPSR_EL1 },
1306                 { ARMV8_PC, ARMV8_xPSR, ARMV8_ELR_EL2, ARMV8_ESR_EL2, ARMV8_SPSR_EL2 },
1307                 { ARMV8_PC, ARMV8_xPSR, ARMV8_ELR_EL3, ARMV8_ESR_EL3, ARMV8_SPSR_EL3 },
1308         };
1309
1310         el = (dpm->dscr >> 8) & 3;
1311
1312         /* safety check, must not happen since EL0 cannot be a target for an exception */
1313         if (el < SYSTEM_CUREL_EL1 || el > SYSTEM_CUREL_EL3) {
1314                 LOG_ERROR("%s: EL %i is invalid, DSCR corrupted?", __func__, el);
1315                 return;
1316         }
1317
1318         /* Clear sticky error */
1319         mem_ap_write_u32(armv8->debug_ap,
1320                 armv8->debug_base + CPUV8_DBG_DRCR, DRCR_CSE);
1321
1322         armv8->read_reg_u64(armv8, ARMV8_xPSR, &dlr);
1323         dspsr = dlr;
1324         armv8->read_reg_u64(armv8, ARMV8_PC, &dlr);
1325
1326         LOG_DEBUG("Exception taken to EL %i, DLR=0x%016"PRIx64" DSPSR=0x%08"PRIx32,
1327                         el, dlr, dspsr);
1328
1329         /* mark all clobbered registers as dirty */
1330         for (int i = 0; i < 5; i++)
1331                 cache->reg_list[clobbered_regs_by_el[el-1][i]].dirty = true;
1332
1333         /*
1334          * re-evaluate the core state, we might be in Aarch64 state now
1335          * we rely on dpm->dscr being up-to-date
1336          */
1337         core_state = armv8_dpm_get_core_state(dpm);
1338         armv8_select_opcodes(armv8, core_state == ARM_STATE_AARCH64);
1339         armv8_select_reg_access(armv8, core_state == ARM_STATE_AARCH64);
1340
1341         if (do_restore)
1342                 armv8_dpm_modeswitch(dpm, ARM_MODE_ANY);
1343 }
1344
1345 /*----------------------------------------------------------------------*/
1346
1347 /*
1348  * Other debug and support utilities
1349  */
1350
1351 void armv8_dpm_report_dscr(struct arm_dpm *dpm, uint32_t dscr)
1352 {
1353         struct target *target = dpm->arm->target;
1354
1355         dpm->dscr = dscr;
1356         dpm->last_el = (dscr >> 8) & 3;
1357
1358         /* Examine debug reason */
1359         switch (DSCR_ENTRY(dscr)) {
1360                 /* FALL THROUGH -- assume a v6 core in abort mode */
1361                 case DSCRV8_ENTRY_EXT_DEBUG:    /* EDBGRQ */
1362                         target->debug_reason = DBG_REASON_DBGRQ;
1363                         break;
1364                 case DSCRV8_ENTRY_HALT_STEP_EXECLU:     /* HALT step */
1365                 case DSCRV8_ENTRY_HALT_STEP_NORMAL: /* Halt step*/
1366                 case DSCRV8_ENTRY_HALT_STEP:
1367                         target->debug_reason = DBG_REASON_SINGLESTEP;
1368                         break;
1369                 case DSCRV8_ENTRY_HLT:  /* HLT instruction (software breakpoint) */
1370                 case DSCRV8_ENTRY_BKPT: /* SW BKPT (?) */
1371                 case DSCRV8_ENTRY_RESET_CATCH:  /* Reset catch */
1372                 case DSCRV8_ENTRY_OS_UNLOCK:  /*OS unlock catch*/
1373                 case DSCRV8_ENTRY_SW_ACCESS_DBG: /*SW access dbg register*/
1374                         target->debug_reason = DBG_REASON_BREAKPOINT;
1375                         break;
1376                 case DSCRV8_ENTRY_WATCHPOINT:   /* asynch watchpoint */
1377                         target->debug_reason = DBG_REASON_WATCHPOINT;
1378                         break;
1379                 case DSCRV8_ENTRY_EXCEPTION_CATCH:  /*exception catch*/
1380                         target->debug_reason = DBG_REASON_EXC_CATCH;
1381                         break;
1382                 default:
1383                         target->debug_reason = DBG_REASON_UNDEFINED;
1384                         break;
1385         }
1386
1387 }
1388
1389 /*----------------------------------------------------------------------*/
1390
1391 /*
1392  * Setup and management support.
1393  */
1394
1395 /**
1396  * Hooks up this DPM to its associated target; call only once.
1397  * Initially this only covers the register cache.
1398  *
1399  * Oh, and watchpoints.  Yeah.
1400  */
1401 int armv8_dpm_setup(struct arm_dpm *dpm)
1402 {
1403         struct arm *arm = dpm->arm;
1404         struct target *target = arm->target;
1405         struct reg_cache *cache;
1406         arm->dpm = dpm;
1407
1408         /* register access setup */
1409         arm->full_context = armv8_dpm_full_context;
1410         arm->read_core_reg = armv8_dpm_read_core_reg;
1411         arm->write_core_reg = armv8_dpm_write_core_reg;
1412
1413         if (arm->core_cache == NULL) {
1414                 cache = armv8_build_reg_cache(target);
1415                 if (!cache)
1416                         return ERROR_FAIL;
1417         }
1418
1419         /* coprocessor access setup */
1420         arm->mrc = dpmv8_mrc;
1421         arm->mcr = dpmv8_mcr;
1422
1423         dpm->prepare = dpmv8_dpm_prepare;
1424         dpm->finish = dpmv8_dpm_finish;
1425
1426         dpm->instr_execute = dpmv8_instr_execute;
1427         dpm->instr_write_data_dcc = dpmv8_instr_write_data_dcc;
1428         dpm->instr_write_data_dcc_64 = dpmv8_instr_write_data_dcc_64;
1429         dpm->instr_write_data_r0 = dpmv8_instr_write_data_r0;
1430         dpm->instr_write_data_r0_64 = dpmv8_instr_write_data_r0_64;
1431         dpm->instr_cpsr_sync = dpmv8_instr_cpsr_sync;
1432
1433         dpm->instr_read_data_dcc = dpmv8_instr_read_data_dcc;
1434         dpm->instr_read_data_dcc_64 = dpmv8_instr_read_data_dcc_64;
1435         dpm->instr_read_data_r0 = dpmv8_instr_read_data_r0;
1436         dpm->instr_read_data_r0_64 = dpmv8_instr_read_data_r0_64;
1437
1438         dpm->arm_reg_current = armv8_reg_current;
1439
1440 /*      dpm->bpwp_enable = dpmv8_bpwp_enable; */
1441         dpm->bpwp_disable = dpmv8_bpwp_disable;
1442
1443         /* breakpoint setup -- optional until it works everywhere */
1444         if (!target->type->add_breakpoint) {
1445                 target->type->add_breakpoint = dpmv8_add_breakpoint;
1446                 target->type->remove_breakpoint = dpmv8_remove_breakpoint;
1447         }
1448
1449         /* watchpoint setup */
1450         if (!target->type->add_watchpoint) {
1451                 target->type->add_watchpoint = dpmv8_add_watchpoint;
1452                 target->type->remove_watchpoint = dpmv8_remove_watchpoint;
1453         }
1454
1455         /* FIXME add vector catch support */
1456
1457         dpm->nbp = 1 + ((dpm->didr >> 12) & 0xf);
1458         dpm->dbp = calloc(dpm->nbp, sizeof(*dpm->dbp));
1459
1460         dpm->nwp = 1 + ((dpm->didr >> 20) & 0xf);
1461         dpm->dwp = calloc(dpm->nwp, sizeof(*dpm->dwp));
1462
1463         if (!dpm->dbp || !dpm->dwp) {
1464                 free(dpm->dbp);
1465                 free(dpm->dwp);
1466                 return ERROR_FAIL;
1467         }
1468
1469         LOG_INFO("%s: hardware has %d breakpoints, %d watchpoints",
1470                 target_name(target), dpm->nbp, dpm->nwp);
1471
1472         /* REVISIT ... and some of those breakpoints could match
1473          * execution context IDs...
1474          */
1475
1476         return ERROR_OK;
1477 }
1478
1479 /**
1480  * Reinitializes DPM state at the beginning of a new debug session
1481  * or after a reset which may have affected the debug module.
1482  */
1483 int armv8_dpm_initialize(struct arm_dpm *dpm)
1484 {
1485         /* Disable all breakpoints and watchpoints at startup. */
1486         if (dpm->bpwp_disable) {
1487                 unsigned i;
1488
1489                 for (i = 0; i < dpm->nbp; i++) {
1490                         dpm->dbp[i].bpwp.number = i;
1491                         (void) dpm->bpwp_disable(dpm, i);
1492                 }
1493                 for (i = 0; i < dpm->nwp; i++) {
1494                         dpm->dwp[i].bpwp.number = 16 + i;
1495                         (void) dpm->bpwp_disable(dpm, 16 + i);
1496                 }
1497         } else
1498                 LOG_WARNING("%s: can't disable breakpoints and watchpoints",
1499                         target_name(dpm->arm->target));
1500
1501         return ERROR_OK;
1502 }