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   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  *   This program is free software; you can redistribute it and/or modify  *
  12  *   it under the terms of the GNU General Public License as published by  *
  13  *   the Free Software Foundation; either version 2 of the License, or     *
  14  *   (at your option) any later version.                                   *
  15  *                                                                         *
  16  *   This program is distributed in the hope that it will be useful,       *
  17  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  18  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  19  *   GNU General Public License for more details.                          *
  20  *                                                                         *
  21  *   You should have received a copy of the GNU General Public License     *
  22  *   along with this program; if not, write to the                         *
  23  *   Free Software Foundation, Inc.,                                       *
  24  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
  25  *                                                                         *
  26  *                                                                         *
  27  *   Cortex-M3(tm) TRM, ARM DDI 0337E (r1p1) and 0337G (r2p0)              *
  28  *                                                                         *
  29  ***************************************************************************/
  30 #ifdef HAVE_CONFIG_H
  31 #include "config.h"
  32 #endif
  33
  34 #include "jtag/interface.h"
  35 #include "breakpoints.h"
  36 #include "cortex_m.h"
  37 #include "target_request.h"
  38 #include "target_type.h"
  39 #include "arm_disassembler.h"
  40 #include "register.h"
  41 #include "arm_opcodes.h"
  42 #include "arm_semihosting.h"
  43 #include <helper/time_support.h>
  44
  45 /* NOTE:  most of this should work fine for the Cortex-M1 and
  46  * Cortex-M0 cores too, although they're ARMv6-M not ARMv7-M.
  47  * Some differences:  M0/M1 doesn't have FBP remapping or the
  48  * DWT tracing/profiling support.  (So the cycle counter will
  49  * not be usable; the other stuff isn't currently used here.)
  50  *
  51  * Although there are some workarounds for errata seen only in r0p0
  52  * silicon, such old parts are hard to find and thus not much tested
  53  * any longer.
  54  */
  55
  56 /**
  57  * Returns the type of a break point required by address location
  58  */
  59 #define BKPT_TYPE_BY_ADDR(addr) ((addr) < 0x20000000 ? BKPT_HARD : BKPT_SOFT)
  60
  61
  62 /* forward declarations */
  63 static int cortex_m3_store_core_reg_u32(struct target *target,
  64         enum armv7m_regtype type, uint32_t num, uint32_t value);
  65
  66 static int cortexm3_dap_read_coreregister_u32(struct adiv5_dap *swjdp,
  67         uint32_t *value, int regnum)
  68 {
  69         int retval;
  70         uint32_t dcrdr;
  71
  72         /* because the DCB_DCRDR is used for the emulated dcc channel
  73          * we have to save/restore the DCB_DCRDR when used */
  74
  75         retval = mem_ap_read_u32(swjdp, DCB_DCRDR, &dcrdr);
  76         if (retval != ERROR_OK)
  77                 return retval;
  78
  79         /* mem_ap_write_u32(swjdp, DCB_DCRSR, regnum); */
  80         retval = dap_setup_accessport(swjdp, CSW_32BIT | CSW_ADDRINC_OFF, DCB_DCRSR & 0xFFFFFFF0);
  81         if (retval != ERROR_OK)
  82                 return retval;
  83         retval = dap_queue_ap_write(swjdp, AP_REG_BD0 | (DCB_DCRSR & 0xC), regnum);
  84         if (retval != ERROR_OK)
  85                 return retval;
  86
  87         /* mem_ap_read_u32(swjdp, DCB_DCRDR, value); */
  88         retval = dap_setup_accessport(swjdp, CSW_32BIT | CSW_ADDRINC_OFF, DCB_DCRDR & 0xFFFFFFF0);
  89         if (retval != ERROR_OK)
  90                 return retval;
  91         retval = dap_queue_ap_read(swjdp, AP_REG_BD0 | (DCB_DCRDR & 0xC), value);
  92         if (retval != ERROR_OK)
  93                 return retval;
  94
  95         retval = dap_run(swjdp);
  96         if (retval != ERROR_OK)
  97                 return retval;
  98
  99         /* restore DCB_DCRDR - this needs to be in a seperate
 100          * transaction otherwise the emulated DCC channel breaks */
 101         if (retval == ERROR_OK)
 102                 retval = mem_ap_write_atomic_u32(swjdp, DCB_DCRDR, dcrdr);
 103
 104         return retval;
 105 }
 106
 107 static int cortexm3_dap_write_coreregister_u32(struct adiv5_dap *swjdp,
 108         uint32_t value, int regnum)
 109 {
 110         int retval;
 111         uint32_t dcrdr;
 112
 113         /* because the DCB_DCRDR is used for the emulated dcc channel
 114          * we have to save/restore the DCB_DCRDR when used */
 115
 116         retval = mem_ap_read_u32(swjdp, DCB_DCRDR, &dcrdr);
 117         if (retval != ERROR_OK)
 118                 return retval;
 119
 120         /* mem_ap_write_u32(swjdp, DCB_DCRDR, core_regs[i]); */
 121         retval = dap_setup_accessport(swjdp, CSW_32BIT | CSW_ADDRINC_OFF, DCB_DCRDR & 0xFFFFFFF0);
 122         if (retval != ERROR_OK)
 123                 return retval;
 124         retval = dap_queue_ap_write(swjdp, AP_REG_BD0 | (DCB_DCRDR & 0xC), value);
 125         if (retval != ERROR_OK)
 126                 return retval;
 127
 128         /* mem_ap_write_u32(swjdp, DCB_DCRSR, i | DCRSR_WnR); */
 129         retval = dap_setup_accessport(swjdp, CSW_32BIT | CSW_ADDRINC_OFF, DCB_DCRSR & 0xFFFFFFF0);
 130         if (retval != ERROR_OK)
 131                 return retval;
 132         retval = dap_queue_ap_write(swjdp, AP_REG_BD0 | (DCB_DCRSR & 0xC), regnum | DCRSR_WnR);
 133         if (retval != ERROR_OK)
 134                 return retval;
 135
 136         retval = dap_run(swjdp);
 137         if (retval != ERROR_OK)
 138                 return retval;
 139
 140         /* restore DCB_DCRDR - this needs to be in a seperate
 141          * transaction otherwise the emulated DCC channel breaks */
 142         if (retval == ERROR_OK)
 143                 retval = mem_ap_write_atomic_u32(swjdp, DCB_DCRDR, dcrdr);
 144
 145         return retval;
 146 }
 147
 148 static int cortex_m3_write_debug_halt_mask(struct target *target,
 149         uint32_t mask_on, uint32_t mask_off)
 150 {
 151         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
 152         struct adiv5_dap *swjdp = cortex_m3->armv7m.arm.dap;
 153
 154         /* mask off status bits */
 155         cortex_m3->dcb_dhcsr &= ~((0xFFFF << 16) | mask_off);
 156         /* create new register mask */
 157         cortex_m3->dcb_dhcsr |= DBGKEY | C_DEBUGEN | mask_on;
 158
 159         return mem_ap_write_atomic_u32(swjdp, DCB_DHCSR, cortex_m3->dcb_dhcsr);
 160 }
 161
 162 static int cortex_m3_clear_halt(struct target *target)
 163 {
 164         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
 165         struct adiv5_dap *swjdp = cortex_m3->armv7m.arm.dap;
 166         int retval;
 167
 168         /* clear step if any */
 169         cortex_m3_write_debug_halt_mask(target, C_HALT, C_STEP);
 170
 171         /* Read Debug Fault Status Register */
 172         retval = mem_ap_read_atomic_u32(swjdp, NVIC_DFSR, &cortex_m3->nvic_dfsr);
 173         if (retval != ERROR_OK)
 174                 return retval;
 175
 176         /* Clear Debug Fault Status */
 177         retval = mem_ap_write_atomic_u32(swjdp, NVIC_DFSR, cortex_m3->nvic_dfsr);
 178         if (retval != ERROR_OK)
 179                 return retval;
 180         LOG_DEBUG(" NVIC_DFSR 0x%" PRIx32 "", cortex_m3->nvic_dfsr);
 181
 182         return ERROR_OK;
 183 }
 184
 185 static int cortex_m3_single_step_core(struct target *target)
 186 {
 187         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
 188         struct adiv5_dap *swjdp = cortex_m3->armv7m.arm.dap;
 189         uint32_t dhcsr_save;
 190         int retval;
 191
 192         /* backup dhcsr reg */
 193         dhcsr_save = cortex_m3->dcb_dhcsr;
 194
 195         /* Mask interrupts before clearing halt, if done already.  This avoids
 196          * Erratum 377497 (fixed in r1p0) where setting MASKINTS while clearing
 197          * HALT can put the core into an unknown state.
 198          */
 199         if (!(cortex_m3->dcb_dhcsr & C_MASKINTS)) {
 200                 retval = mem_ap_write_atomic_u32(swjdp, DCB_DHCSR,
 201                                 DBGKEY | C_MASKINTS | C_HALT | C_DEBUGEN);
 202                 if (retval != ERROR_OK)
 203                         return retval;
 204         }
 205         retval = mem_ap_write_atomic_u32(swjdp, DCB_DHCSR,
 206                         DBGKEY | C_MASKINTS | C_STEP | C_DEBUGEN);
 207         if (retval != ERROR_OK)
 208                 return retval;
 209         LOG_DEBUG(" ");
 210
 211         /* restore dhcsr reg */
 212         cortex_m3->dcb_dhcsr = dhcsr_save;
 213         cortex_m3_clear_halt(target);
 214
 215         return ERROR_OK;
 216 }
 217
 218 static int cortex_m3_endreset_event(struct target *target)
 219 {
 220         int i;
 221         int retval;
 222         uint32_t dcb_demcr;
 223         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
 224         struct armv7m_common *armv7m = &cortex_m3->armv7m;
 225         struct adiv5_dap *swjdp = cortex_m3->armv7m.arm.dap;
 226         struct cortex_m3_fp_comparator *fp_list = cortex_m3->fp_comparator_list;
 227         struct cortex_m3_dwt_comparator *dwt_list = cortex_m3->dwt_comparator_list;
 228
 229         /* REVISIT The four debug monitor bits are currently ignored... */
 230         retval = mem_ap_read_atomic_u32(swjdp, DCB_DEMCR, &dcb_demcr);
 231         if (retval != ERROR_OK)
 232                 return retval;
 233         LOG_DEBUG("DCB_DEMCR = 0x%8.8" PRIx32 "", dcb_demcr);
 234
 235         /* this register is used for emulated dcc channel */
 236         retval = mem_ap_write_u32(swjdp, DCB_DCRDR, 0);
 237         if (retval != ERROR_OK)
 238                 return retval;
 239
 240         /* Enable debug requests */
 241         retval = mem_ap_read_atomic_u32(swjdp, DCB_DHCSR, &cortex_m3->dcb_dhcsr);
 242         if (retval != ERROR_OK)
 243                 return retval;
 244         if (!(cortex_m3->dcb_dhcsr & C_DEBUGEN)) {
 245                 retval = mem_ap_write_u32(swjdp, DCB_DHCSR, DBGKEY | C_DEBUGEN);
 246                 if (retval != ERROR_OK)
 247                         return retval;
 248         }
 249
 250         /* clear any interrupt masking */
 251         cortex_m3_write_debug_halt_mask(target, 0, C_MASKINTS);
 252
 253         /* Enable features controlled by ITM and DWT blocks, and catch only
 254          * the vectors we were told to pay attention to.
 255          *
 256          * Target firmware is responsible for all fault handling policy
 257          * choices *EXCEPT* explicitly scripted overrides like "vector_catch"
 258          * or manual updates to the NVIC SHCSR and CCR registers.
 259          */
 260         retval = mem_ap_write_u32(swjdp, DCB_DEMCR, TRCENA | armv7m->demcr);
 261         if (retval != ERROR_OK)
 262                 return retval;
 263
 264         /* Paranoia: evidently some (early?) chips don't preserve all the
 265          * debug state (including FBP, DWT, etc) across reset...
 266          */
 267
 268         /* Enable FPB */
 269         retval = target_write_u32(target, FP_CTRL, 3);
 270         if (retval != ERROR_OK)
 271                 return retval;
 272
 273         cortex_m3->fpb_enabled = 1;
 274
 275         /* Restore FPB registers */
 276         for (i = 0; i < cortex_m3->fp_num_code + cortex_m3->fp_num_lit; i++) {
 277                 retval = target_write_u32(target, fp_list[i].fpcr_address, fp_list[i].fpcr_value);
 278                 if (retval != ERROR_OK)
 279                         return retval;
 280         }
 281
 282         /* Restore DWT registers */
 283         for (i = 0; i < cortex_m3->dwt_num_comp; i++) {
 284                 retval = target_write_u32(target, dwt_list[i].dwt_comparator_address + 0,
 285                                 dwt_list[i].comp);
 286                 if (retval != ERROR_OK)
 287                         return retval;
 288                 retval = target_write_u32(target, dwt_list[i].dwt_comparator_address + 4,
 289                                 dwt_list[i].mask);
 290                 if (retval != ERROR_OK)
 291                         return retval;
 292                 retval = target_write_u32(target, dwt_list[i].dwt_comparator_address + 8,
 293                                 dwt_list[i].function);
 294                 if (retval != ERROR_OK)
 295                         return retval;
 296         }
 297         retval = dap_run(swjdp);
 298         if (retval != ERROR_OK)
 299                 return retval;
 300
 301         register_cache_invalidate(cortex_m3->armv7m.core_cache);
 302
 303         /* make sure we have latest dhcsr flags */
 304         retval = mem_ap_read_atomic_u32(swjdp, DCB_DHCSR, &cortex_m3->dcb_dhcsr);
 305
 306         return retval;
 307 }
 308
 309 static int cortex_m3_examine_debug_reason(struct target *target)
 310 {
 311         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
 312
 313         /* THIS IS NOT GOOD, TODO - better logic for detection of debug state reason
 314          * only check the debug reason if we don't know it already */
 315
 316         if ((target->debug_reason != DBG_REASON_DBGRQ)
 317                 && (target->debug_reason != DBG_REASON_SINGLESTEP)) {
 318                 if (cortex_m3->nvic_dfsr & DFSR_BKPT) {
 319                         target->debug_reason = DBG_REASON_BREAKPOINT;
 320                         if (cortex_m3->nvic_dfsr & DFSR_DWTTRAP)
 321                                 target->debug_reason = DBG_REASON_WPTANDBKPT;
 322                 } else if (cortex_m3->nvic_dfsr & DFSR_DWTTRAP)
 323                         target->debug_reason = DBG_REASON_WATCHPOINT;
 324                 else if (cortex_m3->nvic_dfsr & DFSR_VCATCH)
 325                         target->debug_reason = DBG_REASON_BREAKPOINT;
 326                 else    /* EXTERNAL, HALTED */
 327                         target->debug_reason = DBG_REASON_UNDEFINED;
 328         }
 329
 330         return ERROR_OK;
 331 }
 332
 333 static int cortex_m3_examine_exception_reason(struct target *target)
 334 {
 335         uint32_t shcsr = 0, except_sr = 0, cfsr = -1, except_ar = -1;
 336         struct armv7m_common *armv7m = target_to_armv7m(target);
 337         struct adiv5_dap *swjdp = armv7m->arm.dap;
 338         int retval;
 339
 340         retval = mem_ap_read_u32(swjdp, NVIC_SHCSR, &shcsr);
 341         if (retval != ERROR_OK)
 342                 return retval;
 343         switch (armv7m->exception_number) {
 344                 case 2: /* NMI */
 345                         break;
 346                 case 3: /* Hard Fault */
 347                         retval = mem_ap_read_atomic_u32(swjdp, NVIC_HFSR, &except_sr);
 348                         if (retval != ERROR_OK)
 349                                 return retval;
 350                         if (except_sr & 0x40000000) {
 351                                 retval = mem_ap_read_u32(swjdp, NVIC_CFSR, &cfsr);
 352                                 if (retval != ERROR_OK)
 353                                         return retval;
 354                         }
 355                         break;
 356                 case 4: /* Memory Management */
 357                         retval = mem_ap_read_u32(swjdp, NVIC_CFSR, &except_sr);
 358                         if (retval != ERROR_OK)
 359                                 return retval;
 360                         retval = mem_ap_read_u32(swjdp, NVIC_MMFAR, &except_ar);
 361                         if (retval != ERROR_OK)
 362                                 return retval;
 363                         break;
 364                 case 5: /* Bus Fault */
 365                         retval = mem_ap_read_u32(swjdp, NVIC_CFSR, &except_sr);
 366                         if (retval != ERROR_OK)
 367                                 return retval;
 368                         retval = mem_ap_read_u32(swjdp, NVIC_BFAR, &except_ar);
 369                         if (retval != ERROR_OK)
 370                                 return retval;
 371                         break;
 372                 case 6: /* Usage Fault */
 373                         retval = mem_ap_read_u32(swjdp, NVIC_CFSR, &except_sr);
 374                         if (retval != ERROR_OK)
 375                                 return retval;
 376                         break;
 377                 case 11:        /* SVCall */
 378                         break;
 379                 case 12:        /* Debug Monitor */
 380                         retval = mem_ap_read_u32(swjdp, NVIC_DFSR, &except_sr);
 381                         if (retval != ERROR_OK)
 382                                 return retval;
 383                         break;
 384                 case 14:        /* PendSV */
 385                         break;
 386                 case 15:        /* SysTick */
 387                         break;
 388                 default:
 389                         except_sr = 0;
 390                         break;
 391         }
 392         retval = dap_run(swjdp);
 393         if (retval == ERROR_OK)
 394                 LOG_DEBUG("%s SHCSR 0x%" PRIx32 ", SR 0x%" PRIx32
 395                         ", CFSR 0x%" PRIx32 ", AR 0x%" PRIx32,
 396                         armv7m_exception_string(armv7m->exception_number),
 397                         shcsr, except_sr, cfsr, except_ar);
 398         return retval;
 399 }
 400
 401 static int cortex_m3_debug_entry(struct target *target)
 402 {
 403         int i;
 404         uint32_t xPSR;
 405         int retval;
 406         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
 407         struct armv7m_common *armv7m = &cortex_m3->armv7m;
 408         struct arm *arm = &armv7m->arm;
 409         struct adiv5_dap *swjdp = armv7m->arm.dap;
 410         struct reg *r;
 411
 412         LOG_DEBUG(" ");
 413
 414         cortex_m3_clear_halt(target);
 415         retval = mem_ap_read_atomic_u32(swjdp, DCB_DHCSR, &cortex_m3->dcb_dhcsr);
 416         if (retval != ERROR_OK)
 417                 return retval;
 418
 419         retval = armv7m->examine_debug_reason(target);
 420         if (retval != ERROR_OK)
 421                 return retval;
 422
 423         /* Examine target state and mode
 424          * First load register acessible through core debug port*/
 425         int num_regs = armv7m->core_cache->num_regs;
 426
 427         for (i = 0; i < num_regs; i++) {
 428                 if (!armv7m->core_cache->reg_list[i].valid)
 429                         armv7m->read_core_reg(target, i);
 430         }
 431
 432         r = armv7m->core_cache->reg_list + ARMV7M_xPSR;
 433         xPSR = buf_get_u32(r->value, 0, 32);
 434
 435 #ifdef ARMV7_GDB_HACKS
 436         /* FIXME this breaks on scan chains with more than one Cortex-M3.
 437          * Instead, each CM3 should have its own dummy value...
 438          */
 439         /* copy real xpsr reg for gdb, setting thumb bit */
 440         buf_set_u32(armv7m_gdb_dummy_cpsr_value, 0, 32, xPSR);
 441         buf_set_u32(armv7m_gdb_dummy_cpsr_value, 5, 1, 1);
 442         armv7m_gdb_dummy_cpsr_reg.valid = r->valid;
 443         armv7m_gdb_dummy_cpsr_reg.dirty = r->dirty;
 444 #endif
 445
 446         /* For IT instructions xPSR must be reloaded on resume and clear on debug exec */
 447         if (xPSR & 0xf00) {
 448                 r->dirty = r->valid;
 449                 cortex_m3_store_core_reg_u32(target, ARMV7M_REGISTER_CORE_GP, 16, xPSR & ~0xff);
 450         }
 451
 452         /* Are we in an exception handler */
 453         if (xPSR & 0x1FF) {
 454                 armv7m->core_mode = ARMV7M_MODE_HANDLER;
 455                 armv7m->exception_number = (xPSR & 0x1FF);
 456
 457                 arm->core_mode = ARM_MODE_HANDLER;
 458                 arm->map = armv7m_msp_reg_map;
 459         } else {
 460                 unsigned control = buf_get_u32(armv7m->core_cache
 461                                 ->reg_list[ARMV7M_CONTROL].value, 0, 2);
 462
 463                 /* is this thread privileged? */
 464                 armv7m->core_mode = control & 1;
 465                 arm->core_mode = armv7m->core_mode
 466                         ? ARM_MODE_USER_THREAD
 467                         : ARM_MODE_THREAD;
 468
 469                 /* which stack is it using? */
 470                 if (control & 2)
 471                         arm->map = armv7m_psp_reg_map;
 472                 else
 473                         arm->map = armv7m_msp_reg_map;
 474
 475                 armv7m->exception_number = 0;
 476         }
 477
 478         if (armv7m->exception_number)
 479                 cortex_m3_examine_exception_reason(target);
 480
 481         LOG_DEBUG("entered debug state in core mode: %s at PC 0x%" PRIx32 ", target->state: %s",
 482                 armv7m_mode_strings[armv7m->core_mode],
 483                 *(uint32_t *)(arm->pc->value),
 484                 target_state_name(target));
 485
 486         if (armv7m->post_debug_entry) {
 487                 retval = armv7m->post_debug_entry(target);
 488                 if (retval != ERROR_OK)
 489                         return retval;
 490         }
 491
 492         return ERROR_OK;
 493 }
 494
 495 static int cortex_m3_poll(struct target *target)
 496 {
 497         int detected_failure = ERROR_OK;
 498         int retval = ERROR_OK;
 499         enum target_state prev_target_state = target->state;
 500         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
 501         struct adiv5_dap *swjdp = cortex_m3->armv7m.arm.dap;
 502
 503         /* Read from Debug Halting Control and Status Register */
 504         retval = mem_ap_read_atomic_u32(swjdp, DCB_DHCSR, &cortex_m3->dcb_dhcsr);
 505         if (retval != ERROR_OK) {
 506                 target->state = TARGET_UNKNOWN;
 507                 return retval;
 508         }
 509
 510         /* Recover from lockup.  See ARMv7-M architecture spec,
 511          * section B1.5.15 "Unrecoverable exception cases".
 512          */
 513         if (cortex_m3->dcb_dhcsr & S_LOCKUP) {
 514                 LOG_ERROR("%s -- clearing lockup after double fault",
 515                         target_name(target));
 516                 cortex_m3_write_debug_halt_mask(target, C_HALT, 0);
 517                 target->debug_reason = DBG_REASON_DBGRQ;
 518
 519                 /* We have to execute the rest (the "finally" equivalent, but
 520                  * still throw this exception again).
 521                  */
 522                 detected_failure = ERROR_FAIL;
 523
 524                 /* refresh status bits */
 525                 retval = mem_ap_read_atomic_u32(swjdp, DCB_DHCSR, &cortex_m3->dcb_dhcsr);
 526                 if (retval != ERROR_OK)
 527                         return retval;
 528         }
 529
 530         if (cortex_m3->dcb_dhcsr & S_RESET_ST) {
 531                 /* check if still in reset */
 532                 retval = mem_ap_read_atomic_u32(swjdp, DCB_DHCSR, &cortex_m3->dcb_dhcsr);
 533                 if (retval != ERROR_OK)
 534                         return retval;
 535
 536                 if (cortex_m3->dcb_dhcsr & S_RESET_ST) {
 537                         target->state = TARGET_RESET;
 538                         return ERROR_OK;
 539                 }
 540         }
 541
 542         if (target->state == TARGET_RESET) {
 543                 /* Cannot switch context while running so endreset is
 544                  * called with target->state == TARGET_RESET
 545                  */
 546                 LOG_DEBUG("Exit from reset with dcb_dhcsr 0x%" PRIx32,
 547                         cortex_m3->dcb_dhcsr);
 548                 cortex_m3_endreset_event(target);
 549                 target->state = TARGET_RUNNING;
 550                 prev_target_state = TARGET_RUNNING;
 551         }
 552
 553         if (cortex_m3->dcb_dhcsr & S_HALT) {
 554                 target->state = TARGET_HALTED;
 555
 556                 if ((prev_target_state == TARGET_RUNNING) || (prev_target_state == TARGET_RESET)) {
 557                         retval = cortex_m3_debug_entry(target);
 558                         if (retval != ERROR_OK)
 559                                 return retval;
 560
 561                         if (arm_semihosting(target, &retval) != 0)
 562                                 return retval;
 563
 564                         target_call_event_callbacks(target, TARGET_EVENT_HALTED);
 565                 }
 566                 if (prev_target_state == TARGET_DEBUG_RUNNING) {
 567                         LOG_DEBUG(" ");
 568                         retval = cortex_m3_debug_entry(target);
 569                         if (retval != ERROR_OK)
 570                                 return retval;
 571
 572                         target_call_event_callbacks(target, TARGET_EVENT_DEBUG_HALTED);
 573                 }
 574         }
 575
 576         /* REVISIT when S_SLEEP is set, it's in a Sleep or DeepSleep state.
 577          * How best to model low power modes?
 578          */
 579
 580         if (target->state == TARGET_UNKNOWN) {
 581                 /* check if processor is retiring instructions */
 582                 if (cortex_m3->dcb_dhcsr & S_RETIRE_ST) {
 583                         target->state = TARGET_RUNNING;
 584                         retval = ERROR_OK;
 585                 }
 586         }
 587
 588         /* Did we detect a failure condition that we cleared? */
 589         if (detected_failure != ERROR_OK)
 590                 retval = detected_failure;
 591         return retval;
 592 }
 593
 594 static int cortex_m3_halt(struct target *target)
 595 {
 596         LOG_DEBUG("target->state: %s",
 597                 target_state_name(target));
 598
 599         if (target->state == TARGET_HALTED) {
 600                 LOG_DEBUG("target was already halted");
 601                 return ERROR_OK;
 602         }
 603
 604         if (target->state == TARGET_UNKNOWN)
 605                 LOG_WARNING("target was in unknown state when halt was requested");
 606
 607         if (target->state == TARGET_RESET) {
 608                 if ((jtag_get_reset_config() & RESET_SRST_PULLS_TRST) && jtag_get_srst()) {
 609                         LOG_ERROR("can't request a halt while in reset if nSRST pulls nTRST");
 610                         return ERROR_TARGET_FAILURE;
 611                 } else {
 612                         /* we came here in a reset_halt or reset_init sequence
 613                          * debug entry was already prepared in cortex_m3_assert_reset()
 614                          */
 615                         target->debug_reason = DBG_REASON_DBGRQ;
 616
 617                         return ERROR_OK;
 618                 }
 619         }
 620
 621         /* Write to Debug Halting Control and Status Register */
 622         cortex_m3_write_debug_halt_mask(target, C_HALT, 0);
 623
 624         target->debug_reason = DBG_REASON_DBGRQ;
 625
 626         return ERROR_OK;
 627 }
 628
 629 static int cortex_m3_soft_reset_halt(struct target *target)
 630 {
 631         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
 632         struct adiv5_dap *swjdp = cortex_m3->armv7m.arm.dap;
 633         uint32_t dcb_dhcsr = 0;
 634         int retval, timeout = 0;
 635
 636         /* Enter debug state on reset; restore DEMCR in endreset_event() */
 637         retval = mem_ap_write_u32(swjdp, DCB_DEMCR,
 638                         TRCENA | VC_HARDERR | VC_BUSERR | VC_CORERESET);
 639         if (retval != ERROR_OK)
 640                 return retval;
 641
 642         /* Request a core-only reset */
 643         retval = mem_ap_write_atomic_u32(swjdp, NVIC_AIRCR,
 644                         AIRCR_VECTKEY | AIRCR_VECTRESET);
 645         if (retval != ERROR_OK)
 646                 return retval;
 647         target->state = TARGET_RESET;
 648
 649         /* registers are now invalid */
 650         register_cache_invalidate(cortex_m3->armv7m.core_cache);
 651
 652         while (timeout < 100) {
 653                 retval = mem_ap_read_atomic_u32(swjdp, DCB_DHCSR, &dcb_dhcsr);
 654                 if (retval == ERROR_OK) {
 655                         retval = mem_ap_read_atomic_u32(swjdp, NVIC_DFSR,
 656                                         &cortex_m3->nvic_dfsr);
 657                         if (retval != ERROR_OK)
 658                                 return retval;
 659                         if ((dcb_dhcsr & S_HALT)
 660                                 && (cortex_m3->nvic_dfsr & DFSR_VCATCH)) {
 661                                 LOG_DEBUG("system reset-halted, DHCSR 0x%08x, "
 662                                         "DFSR 0x%08x",
 663                                         (unsigned) dcb_dhcsr,
 664                                         (unsigned) cortex_m3->nvic_dfsr);
 665                                 cortex_m3_poll(target);
 666                                 /* FIXME restore user's vector catch config */
 667                                 return ERROR_OK;
 668                         } else
 669                                 LOG_DEBUG("waiting for system reset-halt, "
 670                                         "DHCSR 0x%08x, %d ms",
 671                                         (unsigned) dcb_dhcsr, timeout);
 672                 }
 673                 timeout++;
 674                 alive_sleep(1);
 675         }
 676
 677         return ERROR_OK;
 678 }
 679
 680 static void cortex_m3_enable_breakpoints(struct target *target)
 681 {
 682         struct breakpoint *breakpoint = target->breakpoints;
 683
 684         /* set any pending breakpoints */
 685         while (breakpoint) {
 686                 if (!breakpoint->set)
 687                         cortex_m3_set_breakpoint(target, breakpoint);
 688                 breakpoint = breakpoint->next;
 689         }
 690 }
 691
 692 static int cortex_m3_resume(struct target *target, int current,
 693         uint32_t address, int handle_breakpoints, int debug_execution)
 694 {
 695         struct armv7m_common *armv7m = target_to_armv7m(target);
 696         struct breakpoint *breakpoint = NULL;
 697         uint32_t resume_pc;
 698         struct reg *r;
 699
 700         if (target->state != TARGET_HALTED) {
 701                 LOG_WARNING("target not halted");
 702                 return ERROR_TARGET_NOT_HALTED;
 703         }
 704
 705         if (!debug_execution) {
 706                 target_free_all_working_areas(target);
 707                 cortex_m3_enable_breakpoints(target);
 708                 cortex_m3_enable_watchpoints(target);
 709         }
 710
 711         if (debug_execution) {
 712                 r = armv7m->core_cache->reg_list + ARMV7M_PRIMASK;
 713
 714                 /* Disable interrupts */
 715                 /* We disable interrupts in the PRIMASK register instead of
 716                  * masking with C_MASKINTS.  This is probably the same issue
 717                  * as Cortex-M3 Erratum 377493 (fixed in r1p0):  C_MASKINTS
 718                  * in parallel with disabled interrupts can cause local faults
 719                  * to not be taken.
 720                  *
 721                  * REVISIT this clearly breaks non-debug execution, since the
 722                  * PRIMASK register state isn't saved/restored...  workaround
 723                  * by never resuming app code after debug execution.
 724                  */
 725                 buf_set_u32(r->value, 0, 1, 1);
 726                 r->dirty = true;
 727                 r->valid = true;
 728
 729                 /* Make sure we are in Thumb mode */
 730                 r = armv7m->core_cache->reg_list + ARMV7M_xPSR;
 731                 buf_set_u32(r->value, 24, 1, 1);
 732                 r->dirty = true;
 733                 r->valid = true;
 734         }
 735
 736         /* current = 1: continue on current pc, otherwise continue at <address> */
 737         r = armv7m->arm.pc;
 738         if (!current) {
 739                 buf_set_u32(r->value, 0, 32, address);
 740                 r->dirty = true;
 741                 r->valid = true;
 742         }
 743
 744         /* if we halted last time due to a bkpt instruction
 745          * then we have to manually step over it, otherwise
 746          * the core will break again */
 747
 748         if (!breakpoint_find(target, buf_get_u32(r->value, 0, 32))
 749                 && !debug_execution)
 750                 armv7m_maybe_skip_bkpt_inst(target, NULL);
 751
 752         resume_pc = buf_get_u32(r->value, 0, 32);
 753
 754         armv7m_restore_context(target);
 755
 756         /* the front-end may request us not to handle breakpoints */
 757         if (handle_breakpoints) {
 758                 /* Single step past breakpoint at current address */
 759                 breakpoint = breakpoint_find(target, resume_pc);
 760                 if (breakpoint) {
 761                         LOG_DEBUG("unset breakpoint at 0x%8.8" PRIx32 " (ID: %d)",
 762                                 breakpoint->address,
 763                                 breakpoint->unique_id);
 764                         cortex_m3_unset_breakpoint(target, breakpoint);
 765                         cortex_m3_single_step_core(target);
 766                         cortex_m3_set_breakpoint(target, breakpoint);
 767                 }
 768         }
 769
 770         /* Restart core */
 771         cortex_m3_write_debug_halt_mask(target, 0, C_HALT);
 772
 773         target->debug_reason = DBG_REASON_NOTHALTED;
 774
 775         /* registers are now invalid */
 776         register_cache_invalidate(armv7m->core_cache);
 777
 778         if (!debug_execution) {
 779                 target->state = TARGET_RUNNING;
 780                 target_call_event_callbacks(target, TARGET_EVENT_RESUMED);
 781                 LOG_DEBUG("target resumed at 0x%" PRIx32 "", resume_pc);
 782         } else {
 783                 target->state = TARGET_DEBUG_RUNNING;
 784                 target_call_event_callbacks(target, TARGET_EVENT_DEBUG_RESUMED);
 785                 LOG_DEBUG("target debug resumed at 0x%" PRIx32 "", resume_pc);
 786         }
 787
 788         return ERROR_OK;
 789 }
 790
 791 /* int irqstepcount = 0; */
 792 static int cortex_m3_step(struct target *target, int current,
 793         uint32_t address, int handle_breakpoints)
 794 {
 795         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
 796         struct armv7m_common *armv7m = &cortex_m3->armv7m;
 797         struct adiv5_dap *swjdp = armv7m->arm.dap;
 798         struct breakpoint *breakpoint = NULL;
 799         struct reg *pc = armv7m->arm.pc;
 800         bool bkpt_inst_found = false;
 801         int retval;
 802         bool isr_timed_out = false;
 803
 804         if (target->state != TARGET_HALTED) {
 805                 LOG_WARNING("target not halted");
 806                 return ERROR_TARGET_NOT_HALTED;
 807         }
 808
 809         /* current = 1: continue on current pc, otherwise continue at <address> */
 810         if (!current)
 811                 buf_set_u32(pc->value, 0, 32, address);
 812
 813         uint32_t pc_value = buf_get_u32(pc->value, 0, 32);
 814
 815         /* the front-end may request us not to handle breakpoints */
 816         if (handle_breakpoints) {
 817                 breakpoint = breakpoint_find(target, pc_value);
 818                 if (breakpoint)
 819                         cortex_m3_unset_breakpoint(target, breakpoint);
 820         }
 821
 822         armv7m_maybe_skip_bkpt_inst(target, &bkpt_inst_found);
 823
 824         target->debug_reason = DBG_REASON_SINGLESTEP;
 825
 826         armv7m_restore_context(target);
 827
 828         target_call_event_callbacks(target, TARGET_EVENT_RESUMED);
 829
 830         /* if no bkpt instruction is found at pc then we can perform
 831          * a normal step, otherwise we have to manually step over the bkpt
 832          * instruction - as such simulate a step */
 833         if (bkpt_inst_found == false) {
 834                 /* Automatic ISR masking mode off: Just step over the next instruction */
 835                 if ((cortex_m3->isrmasking_mode != CORTEX_M3_ISRMASK_AUTO))
 836                         cortex_m3_write_debug_halt_mask(target, C_STEP, C_HALT);
 837                 else {
 838                         /* Process interrupts during stepping in a way they don't interfere
 839                          * debugging.
 840                          *
 841                          * Principle:
 842                          *
 843                          * Set a temporary break point at the current pc and let the core run
 844                          * with interrupts enabled. Pending interrupts get served and we run
 845                          * into the breakpoint again afterwards. Then we step over the next
 846                          * instruction with interrupts disabled.
 847                          *
 848                          * If the pending interrupts don't complete within time, we leave the
 849                          * core running. This may happen if the interrupts trigger faster
 850                          * than the core can process them or the handler doesn't return.
 851                          *
 852                          * If no more breakpoints are available we simply do a step with
 853                          * interrupts enabled.
 854                          *
 855                          */
 856
 857                         /* Set a temporary break point */
 858                         retval = breakpoint_add(target, pc_value, 2, BKPT_TYPE_BY_ADDR(pc_value));
 859                         bool tmp_bp_set = (retval == ERROR_OK);
 860
 861                         /* No more breakpoints left, just do a step */
 862                         if (!tmp_bp_set)
 863                                 cortex_m3_write_debug_halt_mask(target, C_STEP, C_HALT);
 864                         else {
 865                                 /* Start the core */
 866                                 LOG_DEBUG("Starting core to serve pending interrupts");
 867                                 int64_t t_start = timeval_ms();
 868                                 cortex_m3_write_debug_halt_mask(target, 0, C_HALT | C_STEP);
 869
 870                                 /* Wait for pending handlers to complete or timeout */
 871                                 do {
 872                                         retval = mem_ap_read_atomic_u32(swjdp,
 873                                                         DCB_DHCSR,
 874                                                         &cortex_m3->dcb_dhcsr);
 875                                         if (retval != ERROR_OK) {
 876                                                 target->state = TARGET_UNKNOWN;
 877                                                 return retval;
 878                                         }
 879                                         isr_timed_out = ((timeval_ms() - t_start) > 500);
 880                                 } while (!((cortex_m3->dcb_dhcsr & S_HALT) || isr_timed_out));
 881
 882                                 /* Remove the temporary breakpoint */
 883                                 breakpoint_remove(target, pc_value);
 884
 885                                 if (isr_timed_out) {
 886                                         LOG_DEBUG("Interrupt handlers didn't complete within time, "
 887                                                 "leaving target running");
 888                                 } else {
 889                                         /* Step over next instruction with interrupts disabled */
 890                                         cortex_m3_write_debug_halt_mask(target,
 891                                                 C_HALT | C_MASKINTS,
 892                                                 0);
 893                                         cortex_m3_write_debug_halt_mask(target, C_STEP, C_HALT);
 894                                         /* Re-enable interrupts */
 895                                         cortex_m3_write_debug_halt_mask(target, C_HALT, C_MASKINTS);
 896                                 }
 897                         }
 898                 }
 899         }
 900
 901         retval = mem_ap_read_atomic_u32(swjdp, DCB_DHCSR, &cortex_m3->dcb_dhcsr);
 902         if (retval != ERROR_OK)
 903                 return retval;
 904
 905         /* registers are now invalid */
 906         register_cache_invalidate(cortex_m3->armv7m.core_cache);
 907
 908         if (breakpoint)
 909                 cortex_m3_set_breakpoint(target, breakpoint);
 910
 911         if (isr_timed_out) {
 912                 /* Leave the core running. The user has to stop execution manually. */
 913                 target->debug_reason = DBG_REASON_NOTHALTED;
 914                 target->state = TARGET_RUNNING;
 915                 return ERROR_OK;
 916         }
 917
 918         LOG_DEBUG("target stepped dcb_dhcsr = 0x%" PRIx32
 919                 " nvic_icsr = 0x%" PRIx32,
 920                 cortex_m3->dcb_dhcsr, cortex_m3->nvic_icsr);
 921
 922         retval = cortex_m3_debug_entry(target);
 923         if (retval != ERROR_OK)
 924                 return retval;
 925         target_call_event_callbacks(target, TARGET_EVENT_HALTED);
 926
 927         LOG_DEBUG("target stepped dcb_dhcsr = 0x%" PRIx32
 928                 " nvic_icsr = 0x%" PRIx32,
 929                 cortex_m3->dcb_dhcsr, cortex_m3->nvic_icsr);
 930
 931         return ERROR_OK;
 932 }
 933
 934 static int cortex_m3_assert_reset(struct target *target)
 935 {
 936         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
 937         struct adiv5_dap *swjdp = cortex_m3->armv7m.arm.dap;
 938         enum cortex_m3_soft_reset_config reset_config = cortex_m3->soft_reset_config;
 939
 940         LOG_DEBUG("target->state: %s",
 941                 target_state_name(target));
 942
 943         enum reset_types jtag_reset_config = jtag_get_reset_config();
 944
 945         if (target_has_event_action(target, TARGET_EVENT_RESET_ASSERT)) {
 946                 /* allow scripts to override the reset event */
 947
 948                 target_handle_event(target, TARGET_EVENT_RESET_ASSERT);
 949                 register_cache_invalidate(cortex_m3->armv7m.core_cache);
 950                 target->state = TARGET_RESET;
 951
 952                 return ERROR_OK;
 953         }
 954
 955         /* some cores support connecting while srst is asserted
 956          * use that mode is it has been configured */
 957
 958         bool srst_asserted = false;
 959
 960         if (jtag_reset_config & RESET_SRST_NO_GATING) {
 961                 adapter_assert_reset();
 962                 srst_asserted = true;
 963         }
 964
 965         /* Enable debug requests */
 966         int retval;
 967         retval = mem_ap_read_atomic_u32(swjdp, DCB_DHCSR, &cortex_m3->dcb_dhcsr);
 968         if (retval != ERROR_OK)
 969                 return retval;
 970         if (!(cortex_m3->dcb_dhcsr & C_DEBUGEN)) {
 971                 retval = mem_ap_write_u32(swjdp, DCB_DHCSR, DBGKEY | C_DEBUGEN);
 972                 if (retval != ERROR_OK)
 973                         return retval;
 974         }
 975
 976         /* If the processor is sleeping in a WFI or WFE instruction, the
 977          * C_HALT bit must be asserted to regain control */
 978         if (cortex_m3->dcb_dhcsr & S_SLEEP) {
 979                 retval = mem_ap_write_u32(swjdp, DCB_DHCSR, DBGKEY | C_HALT | C_DEBUGEN);
 980                 if (retval != ERROR_OK)
 981                         return retval;
 982         }
 983
 984         retval = mem_ap_write_u32(swjdp, DCB_DCRDR, 0);
 985         if (retval != ERROR_OK)
 986                 return retval;
 987
 988         if (!target->reset_halt) {
 989                 /* Set/Clear C_MASKINTS in a separate operation */
 990                 if (cortex_m3->dcb_dhcsr & C_MASKINTS) {
 991                         retval = mem_ap_write_atomic_u32(swjdp, DCB_DHCSR,
 992                                         DBGKEY | C_DEBUGEN | C_HALT);
 993                         if (retval != ERROR_OK)
 994                                 return retval;
 995                 }
 996
 997                 /* clear any debug flags before resuming */
 998                 cortex_m3_clear_halt(target);
 999
1000                 /* clear C_HALT in dhcsr reg */
1001                 cortex_m3_write_debug_halt_mask(target, 0, C_HALT);
1002         } else {
1003                 /* Halt in debug on reset; endreset_event() restores DEMCR.
1004                  *
1005                  * REVISIT catching BUSERR presumably helps to defend against
1006                  * bad vector table entries.  Should this include MMERR or
1007                  * other flags too?
1008                  */
1009                 retval = mem_ap_write_atomic_u32(swjdp, DCB_DEMCR,
1010                                 TRCENA | VC_HARDERR | VC_BUSERR | VC_CORERESET);
1011                 if (retval != ERROR_OK)
1012                         return retval;
1013         }
1014
1015         if (jtag_reset_config & RESET_HAS_SRST) {
1016                 /* default to asserting srst */
1017                 if (!srst_asserted)
1018                         adapter_assert_reset();
1019         } else {
1020                 /* Use a standard Cortex-M3 software reset mechanism.
1021                  * We default to using VECRESET as it is supported on all current cores.
1022                  * This has the disadvantage of not resetting the peripherals, so a
1023                  * reset-init event handler is needed to perform any peripheral resets.
1024                  */
1025                 retval = mem_ap_write_atomic_u32(swjdp, NVIC_AIRCR,
1026                                 AIRCR_VECTKEY | ((reset_config == CORTEX_M3_RESET_SYSRESETREQ)
1027                                 ? AIRCR_SYSRESETREQ : AIRCR_VECTRESET));
1028                 if (retval != ERROR_OK)
1029                         return retval;
1030
1031                 LOG_DEBUG("Using Cortex-M3 %s", (reset_config == CORTEX_M3_RESET_SYSRESETREQ)
1032                         ? "SYSRESETREQ" : "VECTRESET");
1033
1034                 if (reset_config == CORTEX_M3_RESET_VECTRESET) {
1035                         LOG_WARNING("Only resetting the Cortex-M3 core, use a reset-init event "
1036                                 "handler to reset any peripherals or configure hardware srst support.");
1037                 }
1038
1039                 {
1040                         /* I do not know why this is necessary, but it
1041                          * fixes strange effects (step/resume cause NMI
1042                          * after reset) on LM3S6918 -- Michael Schwingen
1043                          */
1044                         uint32_t tmp;
1045                         retval = mem_ap_read_atomic_u32(swjdp, NVIC_AIRCR, &tmp);
1046                         if (retval != ERROR_OK)
1047                                 return retval;
1048                 }
1049         }
1050
1051         target->state = TARGET_RESET;
1052         jtag_add_sleep(50000);
1053
1054         register_cache_invalidate(cortex_m3->armv7m.core_cache);
1055
1056         if (target->reset_halt) {
1057                 retval = target_halt(target);
1058                 if (retval != ERROR_OK)
1059                         return retval;
1060         }
1061
1062         return ERROR_OK;
1063 }
1064
1065 static int cortex_m3_deassert_reset(struct target *target)
1066 {
1067         LOG_DEBUG("target->state: %s",
1068                 target_state_name(target));
1069
1070         /* deassert reset lines */
1071         adapter_deassert_reset();
1072
1073         return ERROR_OK;
1074 }
1075
1076 int cortex_m3_set_breakpoint(struct target *target, struct breakpoint *breakpoint)
1077 {
1078         int retval;
1079         int fp_num = 0;
1080         uint32_t hilo;
1081         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
1082         struct cortex_m3_fp_comparator *comparator_list = cortex_m3->fp_comparator_list;
1083
1084         if (breakpoint->set) {
1085                 LOG_WARNING("breakpoint (BPID: %d) already set", breakpoint->unique_id);
1086                 return ERROR_OK;
1087         }
1088
1089         if (cortex_m3->auto_bp_type)
1090                 breakpoint->type = BKPT_TYPE_BY_ADDR(breakpoint->address);
1091
1092         if (breakpoint->type == BKPT_HARD) {
1093                 while (comparator_list[fp_num].used && (fp_num < cortex_m3->fp_num_code))
1094                         fp_num++;
1095                 if (fp_num >= cortex_m3->fp_num_code) {
1096                         LOG_ERROR("Can not find free FPB Comparator!");
1097                         return ERROR_FAIL;
1098                 }
1099                 breakpoint->set = fp_num + 1;
1100                 hilo = (breakpoint->address & 0x2) ? FPCR_REPLACE_BKPT_HIGH : FPCR_REPLACE_BKPT_LOW;
1101                 comparator_list[fp_num].used = 1;
1102                 comparator_list[fp_num].fpcr_value = (breakpoint->address & 0x1FFFFFFC) | hilo | 1;
1103                 target_write_u32(target, comparator_list[fp_num].fpcr_address,
1104                         comparator_list[fp_num].fpcr_value);
1105                 LOG_DEBUG("fpc_num %i fpcr_value 0x%" PRIx32 "",
1106                         fp_num,
1107                         comparator_list[fp_num].fpcr_value);
1108                 if (!cortex_m3->fpb_enabled) {
1109                         LOG_DEBUG("FPB wasn't enabled, do it now");
1110                         target_write_u32(target, FP_CTRL, 3);
1111                 }
1112         } else if (breakpoint->type == BKPT_SOFT) {
1113                 uint8_t code[4];
1114
1115                 /* NOTE: on ARMv6-M and ARMv7-M, BKPT(0xab) is used for
1116                  * semihosting; don't use that.  Otherwise the BKPT
1117                  * parameter is arbitrary.
1118                  */
1119                 buf_set_u32(code, 0, 32, ARMV5_T_BKPT(0x11));
1120                 retval = target_read_memory(target,
1121                                 breakpoint->address & 0xFFFFFFFE,
1122                                 breakpoint->length, 1,
1123                                 breakpoint->orig_instr);
1124                 if (retval != ERROR_OK)
1125                         return retval;
1126                 retval = target_write_memory(target,
1127                                 breakpoint->address & 0xFFFFFFFE,
1128                                 breakpoint->length, 1,
1129                                 code);
1130                 if (retval != ERROR_OK)
1131                         return retval;
1132                 breakpoint->set = true;
1133         }
1134
1135         LOG_DEBUG("BPID: %d, Type: %d, Address: 0x%08" PRIx32 " Length: %d (set=%d)",
1136                 breakpoint->unique_id,
1137                 (int)(breakpoint->type),
1138                 breakpoint->address,
1139                 breakpoint->length,
1140                 breakpoint->set);
1141
1142         return ERROR_OK;
1143 }
1144
1145 int cortex_m3_unset_breakpoint(struct target *target, struct breakpoint *breakpoint)
1146 {
1147         int retval;
1148         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
1149         struct cortex_m3_fp_comparator *comparator_list = cortex_m3->fp_comparator_list;
1150
1151         if (!breakpoint->set) {
1152                 LOG_WARNING("breakpoint not set");
1153                 return ERROR_OK;
1154         }
1155
1156         LOG_DEBUG("BPID: %d, Type: %d, Address: 0x%08" PRIx32 " Length: %d (set=%d)",
1157                 breakpoint->unique_id,
1158                 (int)(breakpoint->type),
1159                 breakpoint->address,
1160                 breakpoint->length,
1161                 breakpoint->set);
1162
1163         if (breakpoint->type == BKPT_HARD) {
1164                 int fp_num = breakpoint->set - 1;
1165                 if ((fp_num < 0) || (fp_num >= cortex_m3->fp_num_code)) {
1166                         LOG_DEBUG("Invalid FP Comparator number in breakpoint");
1167                         return ERROR_OK;
1168                 }
1169                 comparator_list[fp_num].used = 0;
1170                 comparator_list[fp_num].fpcr_value = 0;
1171                 target_write_u32(target, comparator_list[fp_num].fpcr_address,
1172                         comparator_list[fp_num].fpcr_value);
1173         } else {
1174                 /* restore original instruction (kept in target endianness) */
1175                 if (breakpoint->length == 4) {
1176                         retval = target_write_memory(target, breakpoint->address & 0xFFFFFFFE, 4, 1,
1177                                         breakpoint->orig_instr);
1178                         if (retval != ERROR_OK)
1179                                 return retval;
1180                 } else {
1181                         retval = target_write_memory(target, breakpoint->address & 0xFFFFFFFE, 2, 1,
1182                                         breakpoint->orig_instr);
1183                         if (retval != ERROR_OK)
1184                                 return retval;
1185                 }
1186         }
1187         breakpoint->set = false;
1188
1189         return ERROR_OK;
1190 }
1191
1192 int cortex_m3_add_breakpoint(struct target *target, struct breakpoint *breakpoint)
1193 {
1194         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
1195
1196         if (cortex_m3->auto_bp_type) {
1197                 breakpoint->type = BKPT_TYPE_BY_ADDR(breakpoint->address);
1198 #ifdef ARMV7_GDB_HACKS
1199                 if (breakpoint->length != 2) {
1200                         /* XXX Hack: Replace all breakpoints with length != 2 with
1201                          * a hardware breakpoint. */
1202                         breakpoint->type = BKPT_HARD;
1203                         breakpoint->length = 2;
1204                 }
1205 #endif
1206         }
1207
1208         if (breakpoint->type != BKPT_TYPE_BY_ADDR(breakpoint->address)) {
1209                 if (breakpoint->type == BKPT_HARD) {
1210                         LOG_INFO("flash patch comparator requested outside code memory region");
1211                         return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
1212                 }
1213
1214                 if (breakpoint->type == BKPT_SOFT) {
1215                         LOG_INFO("soft breakpoint requested in code (flash) memory region");
1216                         return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
1217                 }
1218         }
1219
1220         if ((breakpoint->type == BKPT_HARD) && (cortex_m3->fp_code_available < 1)) {
1221                 LOG_INFO("no flash patch comparator unit available for hardware breakpoint");
1222                 return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
1223         }
1224
1225         if ((breakpoint->length != 2)) {
1226                 LOG_INFO("only breakpoints of two bytes length supported");
1227                 return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
1228         }
1229
1230         if (breakpoint->type == BKPT_HARD)
1231                 cortex_m3->fp_code_available--;
1232
1233         return cortex_m3_set_breakpoint(target, breakpoint);
1234 }
1235
1236 int cortex_m3_remove_breakpoint(struct target *target, struct breakpoint *breakpoint)
1237 {
1238         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
1239
1240         /* REVISIT why check? FBP can be updated with core running ... */
1241         if (target->state != TARGET_HALTED) {
1242                 LOG_WARNING("target not halted");
1243                 return ERROR_TARGET_NOT_HALTED;
1244         }
1245
1246         if (cortex_m3->auto_bp_type)
1247                 breakpoint->type = BKPT_TYPE_BY_ADDR(breakpoint->address);
1248
1249         if (breakpoint->set)
1250                 cortex_m3_unset_breakpoint(target, breakpoint);
1251
1252         if (breakpoint->type == BKPT_HARD)
1253                 cortex_m3->fp_code_available++;
1254
1255         return ERROR_OK;
1256 }
1257
1258 int cortex_m3_set_watchpoint(struct target *target, struct watchpoint *watchpoint)
1259 {
1260         int dwt_num = 0;
1261         uint32_t mask, temp;
1262         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
1263
1264         /* watchpoint params were validated earlier */
1265         mask = 0;
1266         temp = watchpoint->length;
1267         while (temp) {
1268                 temp >>= 1;
1269                 mask++;
1270         }
1271         mask--;
1272
1273         /* REVISIT Don't fully trust these "not used" records ... users
1274          * may set up breakpoints by hand, e.g. dual-address data value
1275          * watchpoint using comparator #1; comparator #0 matching cycle
1276          * count; send data trace info through ITM and TPIU; etc
1277          */
1278         struct cortex_m3_dwt_comparator *comparator;
1279
1280         for (comparator = cortex_m3->dwt_comparator_list;
1281                 comparator->used && dwt_num < cortex_m3->dwt_num_comp;
1282                 comparator++, dwt_num++)
1283                 continue;
1284         if (dwt_num >= cortex_m3->dwt_num_comp) {
1285                 LOG_ERROR("Can not find free DWT Comparator");
1286                 return ERROR_FAIL;
1287         }
1288         comparator->used = 1;
1289         watchpoint->set = dwt_num + 1;
1290
1291         comparator->comp = watchpoint->address;
1292         target_write_u32(target, comparator->dwt_comparator_address + 0,
1293                 comparator->comp);
1294
1295         comparator->mask = mask;
1296         target_write_u32(target, comparator->dwt_comparator_address + 4,
1297                 comparator->mask);
1298
1299         switch (watchpoint->rw) {
1300                 case WPT_READ:
1301                         comparator->function = 5;
1302                         break;
1303                 case WPT_WRITE:
1304                         comparator->function = 6;
1305                         break;
1306                 case WPT_ACCESS:
1307                         comparator->function = 7;
1308                         break;
1309         }
1310         target_write_u32(target, comparator->dwt_comparator_address + 8,
1311                 comparator->function);
1312
1313         LOG_DEBUG("Watchpoint (ID %d) DWT%d 0x%08x 0x%x 0x%05x",
1314                 watchpoint->unique_id, dwt_num,
1315                 (unsigned) comparator->comp,
1316                 (unsigned) comparator->mask,
1317                 (unsigned) comparator->function);
1318         return ERROR_OK;
1319 }
1320
1321 int cortex_m3_unset_watchpoint(struct target *target, struct watchpoint *watchpoint)
1322 {
1323         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
1324         struct cortex_m3_dwt_comparator *comparator;
1325         int dwt_num;
1326
1327         if (!watchpoint->set) {
1328                 LOG_WARNING("watchpoint (wpid: %d) not set",
1329                         watchpoint->unique_id);
1330                 return ERROR_OK;
1331         }
1332
1333         dwt_num = watchpoint->set - 1;
1334
1335         LOG_DEBUG("Watchpoint (ID %d) DWT%d address: 0x%08x clear",
1336                 watchpoint->unique_id, dwt_num,
1337                 (unsigned) watchpoint->address);
1338
1339         if ((dwt_num < 0) || (dwt_num >= cortex_m3->dwt_num_comp)) {
1340                 LOG_DEBUG("Invalid DWT Comparator number in watchpoint");
1341                 return ERROR_OK;
1342         }
1343
1344         comparator = cortex_m3->dwt_comparator_list + dwt_num;
1345         comparator->used = 0;
1346         comparator->function = 0;
1347         target_write_u32(target, comparator->dwt_comparator_address + 8,
1348                 comparator->function);
1349
1350         watchpoint->set = false;
1351
1352         return ERROR_OK;
1353 }
1354
1355 int cortex_m3_add_watchpoint(struct target *target, struct watchpoint *watchpoint)
1356 {
1357         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
1358
1359         if (cortex_m3->dwt_comp_available < 1) {
1360                 LOG_DEBUG("no comparators?");
1361                 return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
1362         }
1363
1364         /* hardware doesn't support data value masking */
1365         if (watchpoint->mask != ~(uint32_t)0) {
1366                 LOG_DEBUG("watchpoint value masks not supported");
1367                 return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
1368         }
1369
1370         /* hardware allows address masks of up to 32K */
1371         unsigned mask;
1372
1373         for (mask = 0; mask < 16; mask++) {
1374                 if ((1u << mask) == watchpoint->length)
1375                         break;
1376         }
1377         if (mask == 16) {
1378                 LOG_DEBUG("unsupported watchpoint length");
1379                 return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
1380         }
1381         if (watchpoint->address & ((1 << mask) - 1)) {
1382                 LOG_DEBUG("watchpoint address is unaligned");
1383                 return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
1384         }
1385
1386         /* Caller doesn't seem to be able to describe watching for data
1387          * values of zero; that flags "no value".
1388          *
1389          * REVISIT This DWT may well be able to watch for specific data
1390          * values.  Requires comparator #1 to set DATAVMATCH and match
1391          * the data, and another comparator (DATAVADDR0) matching addr.
1392          */
1393         if (watchpoint->value) {
1394                 LOG_DEBUG("data value watchpoint not YET supported");
1395                 return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
1396         }
1397
1398         cortex_m3->dwt_comp_available--;
1399         LOG_DEBUG("dwt_comp_available: %d", cortex_m3->dwt_comp_available);
1400
1401         return ERROR_OK;
1402 }
1403
1404 int cortex_m3_remove_watchpoint(struct target *target, struct watchpoint *watchpoint)
1405 {
1406         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
1407
1408         /* REVISIT why check? DWT can be updated with core running ... */
1409         if (target->state != TARGET_HALTED) {
1410                 LOG_WARNING("target not halted");
1411                 return ERROR_TARGET_NOT_HALTED;
1412         }
1413
1414         if (watchpoint->set)
1415                 cortex_m3_unset_watchpoint(target, watchpoint);
1416
1417         cortex_m3->dwt_comp_available++;
1418         LOG_DEBUG("dwt_comp_available: %d", cortex_m3->dwt_comp_available);
1419
1420         return ERROR_OK;
1421 }
1422
1423 void cortex_m3_enable_watchpoints(struct target *target)
1424 {
1425         struct watchpoint *watchpoint = target->watchpoints;
1426
1427         /* set any pending watchpoints */
1428         while (watchpoint) {
1429                 if (!watchpoint->set)
1430                         cortex_m3_set_watchpoint(target, watchpoint);
1431                 watchpoint = watchpoint->next;
1432         }
1433 }
1434
1435 static int cortex_m3_load_core_reg_u32(struct target *target,
1436         enum armv7m_regtype type, uint32_t num, uint32_t *value)
1437 {
1438         int retval;
1439         struct armv7m_common *armv7m = target_to_armv7m(target);
1440         struct adiv5_dap *swjdp = armv7m->arm.dap;
1441
1442         /* NOTE:  we "know" here that the register identifiers used
1443          * in the v7m header match the Cortex-M3 Debug Core Register
1444          * Selector values for R0..R15, xPSR, MSP, and PSP.
1445          */
1446         switch (num) {
1447                 case 0 ... 18:
1448                         /* read a normal core register */
1449                         retval = cortexm3_dap_read_coreregister_u32(swjdp, value, num);
1450
1451                         if (retval != ERROR_OK) {
1452                                 LOG_ERROR("JTAG failure %i", retval);
1453                                 return ERROR_JTAG_DEVICE_ERROR;
1454                         }
1455                         LOG_DEBUG("load from core reg %i  value 0x%" PRIx32 "", (int)num, *value);
1456                         break;
1457
1458                 case ARMV7M_PRIMASK:
1459                 case ARMV7M_BASEPRI:
1460                 case ARMV7M_FAULTMASK:
1461                 case ARMV7M_CONTROL:
1462                         /* Cortex-M3 packages these four registers as bitfields
1463                          * in one Debug Core register.  So say r0 and r2 docs;
1464                          * it was removed from r1 docs, but still works.
1465                          */
1466                         cortexm3_dap_read_coreregister_u32(swjdp, value, 20);
1467
1468                         switch (num) {
1469                                 case ARMV7M_PRIMASK:
1470                                         *value = buf_get_u32((uint8_t *)value, 0, 1);
1471                                         break;
1472
1473                                 case ARMV7M_BASEPRI:
1474                                         *value = buf_get_u32((uint8_t *)value, 8, 8);
1475                                         break;
1476
1477                                 case ARMV7M_FAULTMASK:
1478                                         *value = buf_get_u32((uint8_t *)value, 16, 1);
1479                                         break;
1480
1481                                 case ARMV7M_CONTROL:
1482                                         *value = buf_get_u32((uint8_t *)value, 24, 2);
1483                                         break;
1484                         }
1485
1486                         LOG_DEBUG("load from special reg %i value 0x%" PRIx32 "", (int)num, *value);
1487                         break;
1488
1489                 default:
1490                         return ERROR_COMMAND_SYNTAX_ERROR;
1491         }
1492
1493         return ERROR_OK;
1494 }
1495
1496 static int cortex_m3_store_core_reg_u32(struct target *target,
1497         enum armv7m_regtype type, uint32_t num, uint32_t value)
1498 {
1499         int retval;
1500         uint32_t reg;
1501         struct armv7m_common *armv7m = target_to_armv7m(target);
1502         struct adiv5_dap *swjdp = armv7m->arm.dap;
1503
1504 #ifdef ARMV7_GDB_HACKS
1505         /* If the LR register is being modified, make sure it will put us
1506          * in "thumb" mode, or an INVSTATE exception will occur. This is a
1507          * hack to deal with the fact that gdb will sometimes "forge"
1508          * return addresses, and doesn't set the LSB correctly (i.e., when
1509          * printing expressions containing function calls, it sets LR = 0.)
1510          * Valid exception return codes have bit 0 set too.
1511          */
1512         if (num == ARMV7M_R14)
1513                 value |= 0x01;
1514 #endif
1515
1516         /* NOTE:  we "know" here that the register identifiers used
1517          * in the v7m header match the Cortex-M3 Debug Core Register
1518          * Selector values for R0..R15, xPSR, MSP, and PSP.
1519          */
1520         switch (num) {
1521                 case 0 ... 18:
1522                         retval = cortexm3_dap_write_coreregister_u32(swjdp, value, num);
1523                         if (retval != ERROR_OK) {
1524                                 struct reg *r;
1525
1526                                 LOG_ERROR("JTAG failure");
1527                                 r = armv7m->core_cache->reg_list + num;
1528                                 r->dirty = r->valid;
1529                                 return ERROR_JTAG_DEVICE_ERROR;
1530                         }
1531                         LOG_DEBUG("write core reg %i value 0x%" PRIx32 "", (int)num, value);
1532                         break;
1533
1534                 case ARMV7M_PRIMASK:
1535                 case ARMV7M_BASEPRI:
1536                 case ARMV7M_FAULTMASK:
1537                 case ARMV7M_CONTROL:
1538                         /* Cortex-M3 packages these four registers as bitfields
1539                          * in one Debug Core register.  So say r0 and r2 docs;
1540                          * it was removed from r1 docs, but still works.
1541                          */
1542                         cortexm3_dap_read_coreregister_u32(swjdp, &reg, 20);
1543
1544                         switch (num) {
1545                                 case ARMV7M_PRIMASK:
1546                                         buf_set_u32((uint8_t *)&reg, 0, 1, value);
1547                                         break;
1548
1549                                 case ARMV7M_BASEPRI:
1550                                         buf_set_u32((uint8_t *)&reg, 8, 8, value);
1551                                         break;
1552
1553                                 case ARMV7M_FAULTMASK:
1554                                         buf_set_u32((uint8_t *)&reg, 16, 1, value);
1555                                         break;
1556
1557                                 case ARMV7M_CONTROL:
1558                                         buf_set_u32((uint8_t *)&reg, 24, 2, value);
1559                                         break;
1560                         }
1561
1562                         cortexm3_dap_write_coreregister_u32(swjdp, reg, 20);
1563
1564                         LOG_DEBUG("write special reg %i value 0x%" PRIx32 " ", (int)num, value);
1565                         break;
1566
1567                 default:
1568                         return ERROR_COMMAND_SYNTAX_ERROR;
1569         }
1570
1571         return ERROR_OK;
1572 }
1573
1574 static int cortex_m3_read_memory(struct target *target, uint32_t address,
1575         uint32_t size, uint32_t count, uint8_t *buffer)
1576 {
1577         struct armv7m_common *armv7m = target_to_armv7m(target);
1578         struct adiv5_dap *swjdp = armv7m->arm.dap;
1579         int retval = ERROR_COMMAND_SYNTAX_ERROR;
1580
1581         if (armv7m->arm.is_armv6m) {
1582                 /* armv6m does not handle unaligned memory access */
1583                 if (((size == 4) && (address & 0x3u)) || ((size == 2) && (address & 0x1u)))
1584                         return ERROR_TARGET_UNALIGNED_ACCESS;
1585         }
1586
1587         /* cortex_m3 handles unaligned memory access */
1588         if (count && buffer) {
1589                 switch (size) {
1590                         case 4:
1591                                 retval = mem_ap_read_buf_u32(swjdp, buffer, 4 * count, address);
1592                                 break;
1593                         case 2:
1594                                 retval = mem_ap_read_buf_u16(swjdp, buffer, 2 * count, address);
1595                                 break;
1596                         case 1:
1597                                 retval = mem_ap_read_buf_u8(swjdp, buffer, count, address);
1598                                 break;
1599                 }
1600         }
1601
1602         return retval;
1603 }
1604
1605 static int cortex_m3_write_memory(struct target *target, uint32_t address,
1606         uint32_t size, uint32_t count, const uint8_t *buffer)
1607 {
1608         struct armv7m_common *armv7m = target_to_armv7m(target);
1609         struct adiv5_dap *swjdp = armv7m->arm.dap;
1610         int retval = ERROR_COMMAND_SYNTAX_ERROR;
1611
1612         if (armv7m->arm.is_armv6m) {
1613                 /* armv6m does not handle unaligned memory access */
1614                 if (((size == 4) && (address & 0x3u)) || ((size == 2) && (address & 0x1u)))
1615                         return ERROR_TARGET_UNALIGNED_ACCESS;
1616         }
1617
1618         if (count && buffer) {
1619                 switch (size) {
1620                         case 4:
1621                                 retval = mem_ap_write_buf_u32(swjdp, buffer, 4 * count, address);
1622                                 break;
1623                         case 2:
1624                                 retval = mem_ap_write_buf_u16(swjdp, buffer, 2 * count, address);
1625                                 break;
1626                         case 1:
1627                                 retval = mem_ap_write_buf_u8(swjdp, buffer, count, address);
1628                                 break;
1629                 }
1630         }
1631
1632         return retval;
1633 }
1634
1635 static int cortex_m3_bulk_write_memory(struct target *target, uint32_t address,
1636         uint32_t count, const uint8_t *buffer)
1637 {
1638         return cortex_m3_write_memory(target, address, 4, count, buffer);
1639 }
1640
1641 static int cortex_m3_init_target(struct command_context *cmd_ctx,
1642         struct target *target)
1643 {
1644         armv7m_build_reg_cache(target);
1645         return ERROR_OK;
1646 }
1647
1648 /* REVISIT cache valid/dirty bits are unmaintained.  We could set "valid"
1649  * on r/w if the core is not running, and clear on resume or reset ... or
1650  * at least, in a post_restore_context() method.
1651  */
1652
1653 struct dwt_reg_state {
1654         struct target *target;
1655         uint32_t addr;
1656         uint32_t value;         /* scratch/cache */
1657 };
1658
1659 static int cortex_m3_dwt_get_reg(struct reg *reg)
1660 {
1661         struct dwt_reg_state *state = reg->arch_info;
1662
1663         return target_read_u32(state->target, state->addr, &state->value);
1664 }
1665
1666 static int cortex_m3_dwt_set_reg(struct reg *reg, uint8_t *buf)
1667 {
1668         struct dwt_reg_state *state = reg->arch_info;
1669
1670         return target_write_u32(state->target, state->addr,
1671                         buf_get_u32(buf, 0, reg->size));
1672 }
1673
1674 struct dwt_reg {
1675         uint32_t addr;
1676         char *name;
1677         unsigned size;
1678 };
1679
1680 static struct dwt_reg dwt_base_regs[] = {
1681         { DWT_CTRL, "dwt_ctrl", 32, },
1682         /* NOTE that Erratum 532314 (fixed r2p0) affects CYCCNT:  it wrongly
1683          * increments while the core is asleep.
1684          */
1685         { DWT_CYCCNT, "dwt_cyccnt", 32, },
1686         /* plus some 8 bit counters, useful for profiling with TPIU */
1687 };
1688
1689 static struct dwt_reg dwt_comp[] = {
1690 #define DWT_COMPARATOR(i) \
1691                 { DWT_COMP0 + 0x10 * (i), "dwt_" #i "_comp", 32, }, \
1692                 { DWT_MASK0 + 0x10 * (i), "dwt_" #i "_mask", 4, }, \
1693                 { DWT_FUNCTION0 + 0x10 * (i), "dwt_" #i "_function", 32, }
1694         DWT_COMPARATOR(0),
1695         DWT_COMPARATOR(1),
1696         DWT_COMPARATOR(2),
1697         DWT_COMPARATOR(3),
1698 #undef DWT_COMPARATOR
1699 };
1700
1701 static const struct reg_arch_type dwt_reg_type = {
1702         .get = cortex_m3_dwt_get_reg,
1703         .set = cortex_m3_dwt_set_reg,
1704 };
1705
1706 static void cortex_m3_dwt_addreg(struct target *t, struct reg *r, struct dwt_reg *d)
1707 {
1708         struct dwt_reg_state *state;
1709
1710         state = calloc(1, sizeof *state);
1711         if (!state)
1712                 return;
1713         state->addr = d->addr;
1714         state->target = t;
1715
1716         r->name = d->name;
1717         r->size = d->size;
1718         r->value = &state->value;
1719         r->arch_info = state;
1720         r->type = &dwt_reg_type;
1721 }
1722
1723 void cortex_m3_dwt_setup(struct cortex_m3_common *cm3, struct target *target)
1724 {
1725         uint32_t dwtcr;
1726         struct reg_cache *cache;
1727         struct cortex_m3_dwt_comparator *comparator;
1728         int reg, i;
1729
1730         target_read_u32(target, DWT_CTRL, &dwtcr);
1731         if (!dwtcr) {
1732                 LOG_DEBUG("no DWT");
1733                 return;
1734         }
1735
1736         cm3->dwt_num_comp = (dwtcr >> 28) & 0xF;
1737         cm3->dwt_comp_available = cm3->dwt_num_comp;
1738         cm3->dwt_comparator_list = calloc(cm3->dwt_num_comp,
1739                         sizeof(struct cortex_m3_dwt_comparator));
1740         if (!cm3->dwt_comparator_list) {
1741 fail0:
1742                 cm3->dwt_num_comp = 0;
1743                 LOG_ERROR("out of mem");
1744                 return;
1745         }
1746
1747         cache = calloc(1, sizeof *cache);
1748         if (!cache) {
1749 fail1:
1750                 free(cm3->dwt_comparator_list);
1751                 goto fail0;
1752         }
1753         cache->name = "cortex-m3 dwt registers";
1754         cache->num_regs = 2 + cm3->dwt_num_comp * 3;
1755         cache->reg_list = calloc(cache->num_regs, sizeof *cache->reg_list);
1756         if (!cache->reg_list) {
1757                 free(cache);
1758                 goto fail1;
1759         }
1760
1761         for (reg = 0; reg < 2; reg++)
1762                 cortex_m3_dwt_addreg(target, cache->reg_list + reg,
1763                         dwt_base_regs + reg);
1764
1765         comparator = cm3->dwt_comparator_list;
1766         for (i = 0; i < cm3->dwt_num_comp; i++, comparator++) {
1767                 int j;
1768
1769                 comparator->dwt_comparator_address = DWT_COMP0 + 0x10 * i;
1770                 for (j = 0; j < 3; j++, reg++)
1771                         cortex_m3_dwt_addreg(target, cache->reg_list + reg,
1772                                 dwt_comp + 3 * i + j);
1773         }
1774
1775         *register_get_last_cache_p(&target->reg_cache) = cache;
1776         cm3->dwt_cache = cache;
1777
1778         LOG_DEBUG("DWT dwtcr 0x%" PRIx32 ", comp %d, watch%s",
1779                 dwtcr, cm3->dwt_num_comp,
1780                 (dwtcr & (0xf << 24)) ? " only" : "/trigger");
1781
1782         /* REVISIT:  if num_comp > 1, check whether comparator #1 can
1783          * implement single-address data value watchpoints ... so we
1784          * won't need to check it later, when asked to set one up.
1785          */
1786 }
1787
1788 #define MVFR0 0xe000ef40
1789 #define MVFR1 0xe000ef44
1790
1791 #define MVFR0_DEFAULT_M4 0x10110021
1792 #define MVFR1_DEFAULT_M4 0x11000011
1793
1794 int cortex_m3_examine(struct target *target)
1795 {
1796         int retval;
1797         uint32_t cpuid, fpcr, mvfr0, mvfr1;
1798         int i;
1799         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
1800         struct adiv5_dap *swjdp = cortex_m3->armv7m.arm.dap;
1801         struct armv7m_common *armv7m = target_to_armv7m(target);
1802
1803         /* stlink shares the examine handler but does not support
1804          * all its calls */
1805         if (!armv7m->stlink) {
1806                 retval = ahbap_debugport_init(swjdp);
1807                 if (retval != ERROR_OK)
1808                         return retval;
1809         }
1810
1811         if (!target_was_examined(target)) {
1812                 target_set_examined(target);
1813
1814                 /* Read from Device Identification Registers */
1815                 retval = target_read_u32(target, CPUID, &cpuid);
1816                 if (retval != ERROR_OK)
1817                         return retval;
1818
1819                 /* Get CPU Type */
1820                 i = (cpuid >> 4) & 0xf;
1821
1822                 LOG_DEBUG("Cortex-M%d r%" PRId8 "p%" PRId8 " processor detected",
1823                                 i, (uint8_t)((cpuid >> 20) & 0xf), (uint8_t)((cpuid >> 0) & 0xf));
1824                 LOG_DEBUG("cpuid: 0x%8.8" PRIx32 "", cpuid);
1825
1826                 /* test for floating point feature on cortex-m4 */
1827                 if (i == 4) {
1828                         target_read_u32(target, MVFR0, &mvfr0);
1829                         target_read_u32(target, MVFR1, &mvfr1);
1830
1831                         if ((mvfr0 == MVFR0_DEFAULT_M4) && (mvfr1 == MVFR1_DEFAULT_M4)) {
1832                                 LOG_DEBUG("Cortex-M%d floating point feature FPv4_SP found", i);
1833                                 armv7m->fp_feature = FPv4_SP;
1834                         }
1835                 } else if (i == 0) {
1836                         /* Cortex-M0 does not support unaligned memory access */
1837                         armv7m->arm.is_armv6m = true;
1838                 }
1839
1840                 if (i == 4 || i == 3) {
1841                         /* Cortex-M3/M4 has 4096 bytes autoincrement range */
1842                         armv7m->dap.tar_autoincr_block = (1 << 12);
1843                 }
1844
1845                 /* NOTE: FPB and DWT are both optional. */
1846
1847                 /* Setup FPB */
1848                 target_read_u32(target, FP_CTRL, &fpcr);
1849                 cortex_m3->auto_bp_type = 1;
1850                 cortex_m3->fp_num_code = ((fpcr >> 8) & 0x70) | ((fpcr >> 4) & 0xF);    /* bits
1851                                                                                          *[14:12]
1852                                                                                          *and [7:4]
1853                                                                                          **/
1854                 cortex_m3->fp_num_lit = (fpcr >> 8) & 0xF;
1855                 cortex_m3->fp_code_available = cortex_m3->fp_num_code;
1856                 cortex_m3->fp_comparator_list = calloc(
1857                                 cortex_m3->fp_num_code + cortex_m3->fp_num_lit,
1858                                 sizeof(struct cortex_m3_fp_comparator));
1859                 cortex_m3->fpb_enabled = fpcr & 1;
1860                 for (i = 0; i < cortex_m3->fp_num_code + cortex_m3->fp_num_lit; i++) {
1861                         cortex_m3->fp_comparator_list[i].type =
1862                                 (i < cortex_m3->fp_num_code) ? FPCR_CODE : FPCR_LITERAL;
1863                         cortex_m3->fp_comparator_list[i].fpcr_address = FP_COMP0 + 4 * i;
1864                 }
1865                 LOG_DEBUG("FPB fpcr 0x%" PRIx32 ", numcode %i, numlit %i",
1866                         fpcr,
1867                         cortex_m3->fp_num_code,
1868                         cortex_m3->fp_num_lit);
1869
1870                 /* Setup DWT */
1871                 cortex_m3_dwt_setup(cortex_m3, target);
1872
1873                 /* These hardware breakpoints only work for code in flash! */
1874                 LOG_INFO("%s: hardware has %d breakpoints, %d watchpoints",
1875                         target_name(target),
1876                         cortex_m3->fp_num_code,
1877                         cortex_m3->dwt_num_comp);
1878         }
1879
1880         return ERROR_OK;
1881 }
1882
1883 static int cortex_m3_dcc_read(struct adiv5_dap *swjdp, uint8_t *value, uint8_t *ctrl)
1884 {
1885         uint16_t dcrdr;
1886         int retval;
1887
1888         mem_ap_read_buf_u16(swjdp, (uint8_t *)&dcrdr, 1, DCB_DCRDR);
1889         *ctrl = (uint8_t)dcrdr;
1890         *value = (uint8_t)(dcrdr >> 8);
1891
1892         LOG_DEBUG("data 0x%x ctrl 0x%x", *value, *ctrl);
1893
1894         /* write ack back to software dcc register
1895          * signify we have read data */
1896         if (dcrdr & (1 << 0)) {
1897                 dcrdr = 0;
1898                 retval = mem_ap_write_buf_u16(swjdp, (uint8_t *)&dcrdr, 1, DCB_DCRDR);
1899                 if (retval != ERROR_OK)
1900                         return retval;
1901         }
1902
1903         return ERROR_OK;
1904 }
1905
1906 static int cortex_m3_target_request_data(struct target *target,
1907         uint32_t size, uint8_t *buffer)
1908 {
1909         struct armv7m_common *armv7m = target_to_armv7m(target);
1910         struct adiv5_dap *swjdp = armv7m->arm.dap;
1911         uint8_t data;
1912         uint8_t ctrl;
1913         uint32_t i;
1914
1915         for (i = 0; i < (size * 4); i++) {
1916                 cortex_m3_dcc_read(swjdp, &data, &ctrl);
1917                 buffer[i] = data;
1918         }
1919
1920         return ERROR_OK;
1921 }
1922
1923 static int cortex_m3_handle_target_request(void *priv)
1924 {
1925         struct target *target = priv;
1926         if (!target_was_examined(target))
1927                 return ERROR_OK;
1928         struct armv7m_common *armv7m = target_to_armv7m(target);
1929         struct adiv5_dap *swjdp = armv7m->arm.dap;
1930
1931         if (!target->dbg_msg_enabled)
1932                 return ERROR_OK;
1933
1934         if (target->state == TARGET_RUNNING) {
1935                 uint8_t data;
1936                 uint8_t ctrl;
1937
1938                 cortex_m3_dcc_read(swjdp, &data, &ctrl);
1939
1940                 /* check if we have data */
1941                 if (ctrl & (1 << 0)) {
1942                         uint32_t request;
1943
1944                         /* we assume target is quick enough */
1945                         request = data;
1946                         cortex_m3_dcc_read(swjdp, &data, &ctrl);
1947                         request |= (data << 8);
1948                         cortex_m3_dcc_read(swjdp, &data, &ctrl);
1949                         request |= (data << 16);
1950                         cortex_m3_dcc_read(swjdp, &data, &ctrl);
1951                         request |= (data << 24);
1952                         target_request(target, request);
1953                 }
1954         }
1955
1956         return ERROR_OK;
1957 }
1958
1959 static int cortex_m3_init_arch_info(struct target *target,
1960         struct cortex_m3_common *cortex_m3, struct jtag_tap *tap)
1961 {
1962         int retval;
1963         struct armv7m_common *armv7m = &cortex_m3->armv7m;
1964
1965         armv7m_init_arch_info(target, armv7m);
1966
1967         /* prepare JTAG information for the new target */
1968         cortex_m3->jtag_info.tap = tap;
1969         cortex_m3->jtag_info.scann_size = 4;
1970
1971         /* default reset mode is to use srst if fitted
1972          * if not it will use CORTEX_M3_RESET_VECTRESET */
1973         cortex_m3->soft_reset_config = CORTEX_M3_RESET_VECTRESET;
1974
1975         armv7m->arm.dap = &armv7m->dap;
1976
1977         /* Leave (only) generic DAP stuff for debugport_init(); */
1978         armv7m->dap.jtag_info = &cortex_m3->jtag_info;
1979         armv7m->dap.memaccess_tck = 8;
1980
1981         /* Cortex-M3/M4 has 4096 bytes autoincrement range
1982          * but set a safe default to 1024 to support Cortex-M0
1983          * this will be changed in cortex_m3_examine if a M3/M4 is detected */
1984         armv7m->dap.tar_autoincr_block = (1 << 10);
1985
1986         /* register arch-specific functions */
1987         armv7m->examine_debug_reason = cortex_m3_examine_debug_reason;
1988
1989         armv7m->post_debug_entry = NULL;
1990
1991         armv7m->pre_restore_context = NULL;
1992
1993         armv7m->load_core_reg_u32 = cortex_m3_load_core_reg_u32;
1994         armv7m->store_core_reg_u32 = cortex_m3_store_core_reg_u32;
1995
1996         target_register_timer_callback(cortex_m3_handle_target_request, 1, 1, target);
1997
1998         retval = arm_jtag_setup_connection(&cortex_m3->jtag_info);
1999         if (retval != ERROR_OK)
2000                 return retval;
2001
2002         return ERROR_OK;
2003 }
2004
2005 static int cortex_m3_target_create(struct target *target, Jim_Interp *interp)
2006 {
2007         struct cortex_m3_common *cortex_m3 = calloc(1, sizeof(struct cortex_m3_common));
2008
2009         cortex_m3->common_magic = CORTEX_M3_COMMON_MAGIC;
2010         cortex_m3_init_arch_info(target, cortex_m3, target->tap);
2011
2012         return ERROR_OK;
2013 }
2014
2015 /*--------------------------------------------------------------------------*/
2016
2017 static int cortex_m3_verify_pointer(struct command_context *cmd_ctx,
2018         struct cortex_m3_common *cm3)
2019 {
2020         if (cm3->common_magic != CORTEX_M3_COMMON_MAGIC) {
2021                 command_print(cmd_ctx, "target is not a Cortex-M3");
2022                 return ERROR_TARGET_INVALID;
2023         }
2024         return ERROR_OK;
2025 }
2026
2027 /*
2028  * Only stuff below this line should need to verify that its target
2029  * is a Cortex-M3.  Everything else should have indirected through the
2030  * cortexm3_target structure, which is only used with CM3 targets.
2031  */
2032
2033 static const struct {
2034         char name[10];
2035         unsigned mask;
2036 } vec_ids[] = {
2037         { "hard_err",   VC_HARDERR, },
2038         { "int_err",    VC_INTERR, },
2039         { "bus_err",    VC_BUSERR, },
2040         { "state_err",  VC_STATERR, },
2041         { "chk_err",    VC_CHKERR, },
2042         { "nocp_err",   VC_NOCPERR, },
2043         { "mm_err",     VC_MMERR, },
2044         { "reset",      VC_CORERESET, },
2045 };
2046
2047 COMMAND_HANDLER(handle_cortex_m3_vector_catch_command)
2048 {
2049         struct target *target = get_current_target(CMD_CTX);
2050         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
2051         struct armv7m_common *armv7m = &cortex_m3->armv7m;
2052         struct adiv5_dap *swjdp = armv7m->arm.dap;
2053         uint32_t demcr = 0;
2054         int retval;
2055
2056         retval = cortex_m3_verify_pointer(CMD_CTX, cortex_m3);
2057         if (retval != ERROR_OK)
2058                 return retval;
2059
2060         retval = mem_ap_read_atomic_u32(swjdp, DCB_DEMCR, &demcr);
2061         if (retval != ERROR_OK)
2062                 return retval;
2063
2064         if (CMD_ARGC > 0) {
2065                 unsigned catch = 0;
2066
2067                 if (CMD_ARGC == 1) {
2068                         if (strcmp(CMD_ARGV[0], "all") == 0) {
2069                                 catch = VC_HARDERR | VC_INTERR | VC_BUSERR
2070                                         | VC_STATERR | VC_CHKERR | VC_NOCPERR
2071                                         | VC_MMERR | VC_CORERESET;
2072                                 goto write;
2073                         } else if (strcmp(CMD_ARGV[0], "none") == 0)
2074                                 goto write;
2075                 }
2076                 while (CMD_ARGC-- > 0) {
2077                         unsigned i;
2078                         for (i = 0; i < ARRAY_SIZE(vec_ids); i++) {
2079                                 if (strcmp(CMD_ARGV[CMD_ARGC], vec_ids[i].name) != 0)
2080                                         continue;
2081                                 catch |= vec_ids[i].mask;
2082                                 break;
2083                         }
2084                         if (i == ARRAY_SIZE(vec_ids)) {
2085                                 LOG_ERROR("No CM3 vector '%s'", CMD_ARGV[CMD_ARGC]);
2086                                 return ERROR_COMMAND_SYNTAX_ERROR;
2087                         }
2088                 }
2089 write:
2090                 /* For now, armv7m->demcr only stores vector catch flags. */
2091                 armv7m->demcr = catch;
2092
2093                 demcr &= ~0xffff;
2094                 demcr |= catch;
2095
2096                 /* write, but don't assume it stuck (why not??) */
2097                 retval = mem_ap_write_u32(swjdp, DCB_DEMCR, demcr);
2098                 if (retval != ERROR_OK)
2099                         return retval;
2100                 retval = mem_ap_read_atomic_u32(swjdp, DCB_DEMCR, &demcr);
2101                 if (retval != ERROR_OK)
2102                         return retval;
2103
2104                 /* FIXME be sure to clear DEMCR on clean server shutdown.
2105                  * Otherwise the vector catch hardware could fire when there's
2106                  * no debugger hooked up, causing much confusion...
2107                  */
2108         }
2109
2110         for (unsigned i = 0; i < ARRAY_SIZE(vec_ids); i++) {
2111                 command_print(CMD_CTX, "%9s: %s", vec_ids[i].name,
2112                         (demcr & vec_ids[i].mask) ? "catch" : "ignore");
2113         }
2114
2115         return ERROR_OK;
2116 }
2117
2118 COMMAND_HANDLER(handle_cortex_m3_mask_interrupts_command)
2119 {
2120         struct target *target = get_current_target(CMD_CTX);
2121         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
2122         int retval;
2123
2124         static const Jim_Nvp nvp_maskisr_modes[] = {
2125                 { .name = "auto", .value = CORTEX_M3_ISRMASK_AUTO },
2126                 { .name = "off", .value = CORTEX_M3_ISRMASK_OFF },
2127                 { .name = "on", .value = CORTEX_M3_ISRMASK_ON },
2128                 { .name = NULL, .value = -1 },
2129         };
2130         const Jim_Nvp *n;
2131
2132
2133         retval = cortex_m3_verify_pointer(CMD_CTX, cortex_m3);
2134         if (retval != ERROR_OK)
2135                 return retval;
2136
2137         if (target->state != TARGET_HALTED) {
2138                 command_print(CMD_CTX, "target must be stopped for \"%s\" command", CMD_NAME);
2139                 return ERROR_OK;
2140         }
2141
2142         if (CMD_ARGC > 0) {
2143                 n = Jim_Nvp_name2value_simple(nvp_maskisr_modes, CMD_ARGV[0]);
2144                 if (n->name == NULL)
2145                         return ERROR_COMMAND_SYNTAX_ERROR;
2146                 cortex_m3->isrmasking_mode = n->value;
2147
2148
2149                 if (cortex_m3->isrmasking_mode == CORTEX_M3_ISRMASK_ON)
2150                         cortex_m3_write_debug_halt_mask(target, C_HALT | C_MASKINTS, 0);
2151                 else
2152                         cortex_m3_write_debug_halt_mask(target, C_HALT, C_MASKINTS);
2153         }
2154
2155         n = Jim_Nvp_value2name_simple(nvp_maskisr_modes, cortex_m3->isrmasking_mode);
2156         command_print(CMD_CTX, "cortex_m3 interrupt mask %s", n->name);
2157
2158         return ERROR_OK;
2159 }
2160
2161 COMMAND_HANDLER(handle_cortex_m3_reset_config_command)
2162 {
2163         struct target *target = get_current_target(CMD_CTX);
2164         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
2165         int retval;
2166         char *reset_config;
2167
2168         retval = cortex_m3_verify_pointer(CMD_CTX, cortex_m3);
2169         if (retval != ERROR_OK)
2170                 return retval;
2171
2172         if (CMD_ARGC > 0) {
2173                 if (strcmp(*CMD_ARGV, "sysresetreq") == 0)
2174                         cortex_m3->soft_reset_config = CORTEX_M3_RESET_SYSRESETREQ;
2175                 else if (strcmp(*CMD_ARGV, "vectreset") == 0)
2176                         cortex_m3->soft_reset_config = CORTEX_M3_RESET_VECTRESET;
2177         }
2178
2179         switch (cortex_m3->soft_reset_config) {
2180                 case CORTEX_M3_RESET_SYSRESETREQ:
2181                         reset_config = "sysresetreq";
2182                         break;
2183
2184                 case CORTEX_M3_RESET_VECTRESET:
2185                         reset_config = "vectreset";
2186                         break;
2187
2188                 default:
2189                         reset_config = "unknown";
2190                         break;
2191         }
2192
2193         command_print(CMD_CTX, "cortex_m3 reset_config %s", reset_config);
2194
2195         return ERROR_OK;
2196 }
2197
2198 static const struct command_registration cortex_m3_exec_command_handlers[] = {
2199         {
2200                 .name = "maskisr",
2201                 .handler = handle_cortex_m3_mask_interrupts_command,
2202                 .mode = COMMAND_EXEC,
2203                 .help = "mask cortex_m3 interrupts",
2204                 .usage = "['auto'|'on'|'off']",
2205         },
2206         {
2207                 .name = "vector_catch",
2208                 .handler = handle_cortex_m3_vector_catch_command,
2209                 .mode = COMMAND_EXEC,
2210                 .help = "configure hardware vectors to trigger debug entry",
2211                 .usage = "['all'|'none'|('bus_err'|'chk_err'|...)*]",
2212         },
2213         {
2214                 .name = "reset_config",
2215                 .handler = handle_cortex_m3_reset_config_command,
2216                 .mode = COMMAND_ANY,
2217                 .help = "configure software reset handling",
2218                 .usage = "['srst'|'sysresetreq'|'vectreset']",
2219         },
2220         COMMAND_REGISTRATION_DONE
2221 };
2222 static const struct command_registration cortex_m3_command_handlers[] = {
2223         {
2224                 .chain = armv7m_command_handlers,
2225         },
2226         {
2227                 .name = "cortex_m3",
2228                 .mode = COMMAND_EXEC,
2229                 .help = "Cortex-M3 command group",
2230                 .usage = "",
2231                 .chain = cortex_m3_exec_command_handlers,
2232         },
2233         COMMAND_REGISTRATION_DONE
2234 };
2235
2236 struct target_type cortexm3_target = {
2237         .name = "cortex_m3",
2238
2239         .poll = cortex_m3_poll,
2240         .arch_state = armv7m_arch_state,
2241
2242         .target_request_data = cortex_m3_target_request_data,
2243
2244         .halt = cortex_m3_halt,
2245         .resume = cortex_m3_resume,
2246         .step = cortex_m3_step,
2247
2248         .assert_reset = cortex_m3_assert_reset,
2249         .deassert_reset = cortex_m3_deassert_reset,
2250         .soft_reset_halt = cortex_m3_soft_reset_halt,
2251
2252         .get_gdb_reg_list = armv7m_get_gdb_reg_list,
2253
2254         .read_memory = cortex_m3_read_memory,
2255         .write_memory = cortex_m3_write_memory,
2256         .bulk_write_memory = cortex_m3_bulk_write_memory,
2257         .checksum_memory = armv7m_checksum_memory,
2258         .blank_check_memory = armv7m_blank_check_memory,
2259
2260         .run_algorithm = armv7m_run_algorithm,
2261         .start_algorithm = armv7m_start_algorithm,
2262         .wait_algorithm = armv7m_wait_algorithm,
2263
2264         .add_breakpoint = cortex_m3_add_breakpoint,
2265         .remove_breakpoint = cortex_m3_remove_breakpoint,
2266         .add_watchpoint = cortex_m3_add_watchpoint,
2267         .remove_watchpoint = cortex_m3_remove_watchpoint,
2268
2269         .commands = cortex_m3_command_handlers,
2270         .target_create = cortex_m3_target_create,
2271         .init_target = cortex_m3_init_target,
2272         .examine = cortex_m3_examine,
2273 };