2 * Copyright (C) 2009 by David Brownell
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
22 #include "armv8_dpm.h"
23 #include <jtag/jtag.h>
25 #include "breakpoints.h"
26 #include "target_type.h"
27 #include "armv8_opcodes.h"
29 #include "helper/time_support.h"
32 #define T32_FMTITR(instr) (((instr & 0x0000FFFF) << 16) | ((instr & 0xFFFF0000) >> 16))
36 * Implements various ARM DPM operations using architectural debug registers.
37 * These routines layer over core-specific communication methods to cope with
38 * implementation differences between cores like ARM1136 and Cortex-A8.
40 * The "Debug Programmers' Model" (DPM) for ARMv6 and ARMv7 is defined by
41 * Part C (Debug Architecture) of the ARM Architecture Reference Manual,
42 * ARMv7-A and ARMv7-R edition (ARM DDI 0406B). In OpenOCD, DPM operations
43 * are abstracted through internal programming interfaces to share code and
44 * to minimize needless differences in debug behavior between cores.
48 * Get core state from EDSCR, without necessity to retrieve CPSR
50 enum arm_state armv8_dpm_get_core_state(struct arm_dpm *dpm)
52 int el = (dpm->dscr >> 8) & 0x3;
53 int rw = (dpm->dscr >> 10) & 0xF;
57 /* In Debug state, each bit gives the current Execution state of each EL */
59 return ARM_STATE_AARCH64;
64 /*----------------------------------------------------------------------*/
66 static int dpmv8_write_dcc(struct armv8_common *armv8, uint32_t data)
68 return mem_ap_write_u32(armv8->debug_ap,
69 armv8->debug_base + CPUV8_DBG_DTRRX, data);
72 static int dpmv8_write_dcc_64(struct armv8_common *armv8, uint64_t data)
75 ret = mem_ap_write_u32(armv8->debug_ap,
76 armv8->debug_base + CPUV8_DBG_DTRRX, data);
78 ret = mem_ap_write_u32(armv8->debug_ap,
79 armv8->debug_base + CPUV8_DBG_DTRTX, data >> 32);
83 static int dpmv8_read_dcc(struct armv8_common *armv8, uint32_t *data,
86 uint32_t dscr = DSCR_ITE;
92 /* Wait for DTRRXfull */
93 long long then = timeval_ms();
94 while ((dscr & DSCR_DTR_TX_FULL) == 0) {
95 retval = mem_ap_read_atomic_u32(armv8->debug_ap,
96 armv8->debug_base + CPUV8_DBG_DSCR,
98 if (retval != ERROR_OK)
100 if (timeval_ms() > then + 1000) {
101 LOG_ERROR("Timeout waiting for read dcc");
106 retval = mem_ap_read_atomic_u32(armv8->debug_ap,
107 armv8->debug_base + CPUV8_DBG_DTRTX,
109 if (retval != ERROR_OK)
118 static int dpmv8_read_dcc_64(struct armv8_common *armv8, uint64_t *data,
121 uint32_t dscr = DSCR_ITE;
128 /* Wait for DTRRXfull */
129 long long then = timeval_ms();
130 while ((dscr & DSCR_DTR_TX_FULL) == 0) {
131 retval = mem_ap_read_atomic_u32(armv8->debug_ap,
132 armv8->debug_base + CPUV8_DBG_DSCR,
134 if (retval != ERROR_OK)
136 if (timeval_ms() > then + 1000) {
137 LOG_ERROR("Timeout waiting for DTR_TX_FULL, dscr = 0x%08" PRIx32, dscr);
142 retval = mem_ap_read_atomic_u32(armv8->debug_ap,
143 armv8->debug_base + CPUV8_DBG_DTRTX,
145 if (retval != ERROR_OK)
148 retval = mem_ap_read_atomic_u32(armv8->debug_ap,
149 armv8->debug_base + CPUV8_DBG_DTRRX,
151 if (retval != ERROR_OK)
154 *data = *(uint32_t *)data | (uint64_t)higher << 32;
162 static int dpmv8_dpm_prepare(struct arm_dpm *dpm)
164 struct armv8_common *armv8 = dpm->arm->arch_info;
168 /* set up invariant: ITE is set after ever DPM operation */
169 long long then = timeval_ms();
171 retval = mem_ap_read_atomic_u32(armv8->debug_ap,
172 armv8->debug_base + CPUV8_DBG_DSCR,
174 if (retval != ERROR_OK)
176 if ((dscr & DSCR_ITE) != 0)
178 if (timeval_ms() > then + 1000) {
179 LOG_ERROR("Timeout waiting for dpm prepare");
184 /* update the stored copy of dscr */
187 /* this "should never happen" ... */
188 if (dscr & DSCR_DTR_RX_FULL) {
189 LOG_ERROR("DSCR_DTR_RX_FULL, dscr 0x%08" PRIx32, dscr);
191 retval = mem_ap_read_u32(armv8->debug_ap,
192 armv8->debug_base + CPUV8_DBG_DTRRX, &dscr);
193 if (retval != ERROR_OK)
200 static int dpmv8_dpm_finish(struct arm_dpm *dpm)
202 /* REVISIT what could be done here? */
206 static int dpmv8_exec_opcode(struct arm_dpm *dpm,
207 uint32_t opcode, uint32_t *p_dscr)
209 struct armv8_common *armv8 = dpm->arm->arch_info;
210 uint32_t dscr = dpm->dscr;
216 /* Wait for InstrCompl bit to be set */
217 long long then = timeval_ms();
218 while ((dscr & DSCR_ITE) == 0) {
219 retval = mem_ap_read_atomic_u32(armv8->debug_ap,
220 armv8->debug_base + CPUV8_DBG_DSCR, &dscr);
221 if (retval != ERROR_OK) {
222 LOG_ERROR("Could not read DSCR register, opcode = 0x%08" PRIx32, opcode);
225 if (timeval_ms() > then + 1000) {
226 LOG_ERROR("Timeout waiting for aarch64_exec_opcode");
231 if (armv8_dpm_get_core_state(dpm) != ARM_STATE_AARCH64)
232 opcode = T32_FMTITR(opcode);
234 retval = mem_ap_write_u32(armv8->debug_ap,
235 armv8->debug_base + CPUV8_DBG_ITR, opcode);
236 if (retval != ERROR_OK)
241 retval = mem_ap_read_atomic_u32(armv8->debug_ap,
242 armv8->debug_base + CPUV8_DBG_DSCR, &dscr);
243 if (retval != ERROR_OK) {
244 LOG_ERROR("Could not read DSCR register");
247 if (timeval_ms() > then + 1000) {
248 LOG_ERROR("Timeout waiting for aarch64_exec_opcode");
251 } while ((dscr & DSCR_ITE) == 0); /* Wait for InstrCompl bit to be set */
253 /* update dscr and el after each command execution */
255 if (dpm->last_el != ((dscr >> 8) & 3))
256 LOG_DEBUG("EL %i -> %i", dpm->last_el, (dscr >> 8) & 3);
257 dpm->last_el = (dscr >> 8) & 3;
259 if (dscr & DSCR_ERR) {
260 LOG_ERROR("Opcode 0x%08"PRIx32", DSCR.ERR=1, DSCR.EL=%i", opcode, dpm->last_el);
261 armv8_dpm_handle_exception(dpm, true);
271 static int dpmv8_instr_execute(struct arm_dpm *dpm, uint32_t opcode)
273 return dpmv8_exec_opcode(dpm, opcode, NULL);
276 static int dpmv8_instr_write_data_dcc(struct arm_dpm *dpm,
277 uint32_t opcode, uint32_t data)
279 struct armv8_common *armv8 = dpm->arm->arch_info;
282 retval = dpmv8_write_dcc(armv8, data);
283 if (retval != ERROR_OK)
286 return dpmv8_exec_opcode(dpm, opcode, 0);
289 static int dpmv8_instr_write_data_dcc_64(struct arm_dpm *dpm,
290 uint32_t opcode, uint64_t data)
292 struct armv8_common *armv8 = dpm->arm->arch_info;
295 retval = dpmv8_write_dcc_64(armv8, data);
296 if (retval != ERROR_OK)
299 return dpmv8_exec_opcode(dpm, opcode, 0);
302 static int dpmv8_instr_write_data_r0(struct arm_dpm *dpm,
303 uint32_t opcode, uint32_t data)
305 struct armv8_common *armv8 = dpm->arm->arch_info;
306 uint32_t dscr = DSCR_ITE;
309 retval = dpmv8_write_dcc(armv8, data);
310 if (retval != ERROR_OK)
313 retval = dpmv8_exec_opcode(dpm, armv8_opcode(armv8, READ_REG_DTRRX), &dscr);
314 if (retval != ERROR_OK)
317 /* then the opcode, taking data from R0 */
318 return dpmv8_exec_opcode(dpm, opcode, &dscr);
321 static int dpmv8_instr_write_data_r0_64(struct arm_dpm *dpm,
322 uint32_t opcode, uint64_t data)
324 struct armv8_common *armv8 = dpm->arm->arch_info;
327 if (dpm->arm->core_state != ARM_STATE_AARCH64)
328 return dpmv8_instr_write_data_r0(dpm, opcode, data);
330 /* transfer data from DCC to R0 */
331 retval = dpmv8_write_dcc_64(armv8, data);
332 if (retval == ERROR_OK)
333 retval = dpmv8_exec_opcode(dpm, ARMV8_MRS(SYSTEM_DBG_DBGDTR_EL0, 0), &dpm->dscr);
335 /* then the opcode, taking data from R0 */
336 if (retval == ERROR_OK)
337 retval = dpmv8_exec_opcode(dpm, opcode, &dpm->dscr);
342 static int dpmv8_instr_cpsr_sync(struct arm_dpm *dpm)
345 struct armv8_common *armv8 = dpm->arm->arch_info;
347 /* "Prefetch flush" after modifying execution status in CPSR */
348 retval = dpmv8_exec_opcode(dpm, armv8_opcode(armv8, ARMV8_OPC_DSB_SY), &dpm->dscr);
349 if (retval == ERROR_OK)
350 dpmv8_exec_opcode(dpm, armv8_opcode(armv8, ARMV8_OPC_ISB_SY), &dpm->dscr);
354 static int dpmv8_instr_read_data_dcc(struct arm_dpm *dpm,
355 uint32_t opcode, uint32_t *data)
357 struct armv8_common *armv8 = dpm->arm->arch_info;
360 /* the opcode, writing data to DCC */
361 retval = dpmv8_exec_opcode(dpm, opcode, &dpm->dscr);
362 if (retval != ERROR_OK)
365 return dpmv8_read_dcc(armv8, data, &dpm->dscr);
368 static int dpmv8_instr_read_data_dcc_64(struct arm_dpm *dpm,
369 uint32_t opcode, uint64_t *data)
371 struct armv8_common *armv8 = dpm->arm->arch_info;
374 /* the opcode, writing data to DCC */
375 retval = dpmv8_exec_opcode(dpm, opcode, &dpm->dscr);
376 if (retval != ERROR_OK)
379 return dpmv8_read_dcc_64(armv8, data, &dpm->dscr);
382 static int dpmv8_instr_read_data_r0(struct arm_dpm *dpm,
383 uint32_t opcode, uint32_t *data)
385 struct armv8_common *armv8 = dpm->arm->arch_info;
388 /* the opcode, writing data to R0 */
389 retval = dpmv8_exec_opcode(dpm, opcode, &dpm->dscr);
390 if (retval != ERROR_OK)
393 /* write R0 to DCC */
394 retval = dpmv8_exec_opcode(dpm, armv8_opcode(armv8, WRITE_REG_DTRTX), &dpm->dscr);
395 if (retval != ERROR_OK)
398 return dpmv8_read_dcc(armv8, data, &dpm->dscr);
401 static int dpmv8_instr_read_data_r0_64(struct arm_dpm *dpm,
402 uint32_t opcode, uint64_t *data)
404 struct armv8_common *armv8 = dpm->arm->arch_info;
407 if (dpm->arm->core_state != ARM_STATE_AARCH64) {
409 retval = dpmv8_instr_read_data_r0(dpm, opcode, &tmp);
410 if (retval == ERROR_OK)
415 /* the opcode, writing data to R0 */
416 retval = dpmv8_exec_opcode(dpm, opcode, &dpm->dscr);
417 if (retval != ERROR_OK)
420 /* write R0 to DCC */
421 retval = dpmv8_exec_opcode(dpm, ARMV8_MSR_GP(SYSTEM_DBG_DBGDTR_EL0, 0), &dpm->dscr);
422 if (retval != ERROR_OK)
425 return dpmv8_read_dcc_64(armv8, data, &dpm->dscr);
429 static int dpmv8_bpwp_enable(struct arm_dpm *dpm, unsigned index_t,
430 target_addr_t addr, uint32_t control)
432 struct armv8_common *armv8 = dpm->arm->arch_info;
433 uint32_t vr = armv8->debug_base;
434 uint32_t cr = armv8->debug_base;
438 case 0 ... 15: /* breakpoints */
439 vr += CPUV8_DBG_BVR_BASE;
440 cr += CPUV8_DBG_BCR_BASE;
442 case 16 ... 31: /* watchpoints */
443 vr += CPUV8_DBG_WVR_BASE;
444 cr += CPUV8_DBG_WCR_BASE;
453 LOG_DEBUG("A8: bpwp enable, vr %08x cr %08x",
454 (unsigned) vr, (unsigned) cr);
456 retval = mem_ap_write_atomic_u32(armv8->debug_ap, vr, addr);
457 if (retval != ERROR_OK)
459 return mem_ap_write_atomic_u32(armv8->debug_ap, cr, control);
463 static int dpmv8_bpwp_disable(struct arm_dpm *dpm, unsigned index_t)
465 struct armv8_common *armv8 = dpm->arm->arch_info;
470 cr = armv8->debug_base + CPUV8_DBG_BCR_BASE;
473 cr = armv8->debug_base + CPUV8_DBG_WCR_BASE;
481 LOG_DEBUG("A: bpwp disable, cr %08x", (unsigned) cr);
483 /* clear control register */
484 return mem_ap_write_atomic_u32(armv8->debug_ap, cr, 0);
488 * Coprocessor support
491 /* Read coprocessor */
492 static int dpmv8_mrc(struct target *target, int cpnum,
493 uint32_t op1, uint32_t op2, uint32_t CRn, uint32_t CRm,
496 struct arm *arm = target_to_arm(target);
497 struct arm_dpm *dpm = arm->dpm;
500 retval = dpm->prepare(dpm);
501 if (retval != ERROR_OK)
504 LOG_DEBUG("MRC p%d, %d, r0, c%d, c%d, %d", cpnum,
505 (int) op1, (int) CRn,
506 (int) CRm, (int) op2);
508 /* read coprocessor register into R0; return via DCC */
509 retval = dpm->instr_read_data_r0(dpm,
510 ARMV4_5_MRC(cpnum, op1, 0, CRn, CRm, op2),
513 /* (void) */ dpm->finish(dpm);
517 static int dpmv8_mcr(struct target *target, int cpnum,
518 uint32_t op1, uint32_t op2, uint32_t CRn, uint32_t CRm,
521 struct arm *arm = target_to_arm(target);
522 struct arm_dpm *dpm = arm->dpm;
525 retval = dpm->prepare(dpm);
526 if (retval != ERROR_OK)
529 LOG_DEBUG("MCR p%d, %d, r0, c%d, c%d, %d", cpnum,
530 (int) op1, (int) CRn,
531 (int) CRm, (int) op2);
533 /* read DCC into r0; then write coprocessor register from R0 */
534 retval = dpm->instr_write_data_r0(dpm,
535 ARMV4_5_MCR(cpnum, op1, 0, CRn, CRm, op2),
538 /* (void) */ dpm->finish(dpm);
542 /*----------------------------------------------------------------------*/
545 * Register access utilities
548 int armv8_dpm_modeswitch(struct arm_dpm *dpm, enum arm_mode mode)
550 struct armv8_common *armv8 = (struct armv8_common *)dpm->arm->arch_info;
551 int retval = ERROR_OK;
552 unsigned int target_el;
553 enum arm_state core_state;
556 /* restore previous mode */
557 if (mode == ARM_MODE_ANY) {
558 cpsr = buf_get_u32(dpm->arm->cpsr->value, 0, 32);
560 LOG_DEBUG("restoring mode, cpsr = 0x%08"PRIx32, cpsr);
563 LOG_DEBUG("setting mode 0x%"PRIx32, mode);
567 switch (cpsr & 0x1f) {
579 * TODO: handle ARM_MODE_HYP
589 target_el = (cpsr >> 2) & 3;
592 if (target_el > SYSTEM_CUREL_EL3) {
593 LOG_ERROR("%s: Invalid target exception level %i", __func__, target_el);
597 LOG_DEBUG("target_el = %i, last_el = %i", target_el, dpm->last_el);
598 if (target_el > dpm->last_el) {
599 retval = dpm->instr_execute(dpm,
600 armv8_opcode(armv8, ARMV8_OPC_DCPS) | target_el);
602 /* DCPS clobbers registers just like an exception taken */
603 armv8_dpm_handle_exception(dpm, false);
605 core_state = armv8_dpm_get_core_state(dpm);
606 if (core_state != ARM_STATE_AARCH64) {
607 /* cannot do DRPS/ERET when already in EL0 */
608 if (dpm->last_el != 0) {
609 /* load SPSR with the desired mode and execute DRPS */
610 LOG_DEBUG("SPSR = 0x%08"PRIx32, cpsr);
611 retval = dpm->instr_write_data_r0(dpm,
612 ARMV8_MSR_GP_xPSR_T1(1, 0, 15), cpsr);
613 if (retval == ERROR_OK)
614 retval = dpm->instr_execute(dpm, armv8_opcode(armv8, ARMV8_OPC_DRPS));
618 * need to execute multiple DRPS instructions until target_el
621 while (retval == ERROR_OK && dpm->last_el != target_el) {
622 unsigned int cur_el = dpm->last_el;
623 retval = dpm->instr_execute(dpm, armv8_opcode(armv8, ARMV8_OPC_DRPS));
624 if (cur_el == dpm->last_el) {
625 LOG_INFO("Cannot reach EL %i, SPSR corrupted?", target_el);
631 /* On executing DRPS, DSPSR and DLR become UNKNOWN, mark them as dirty */
632 dpm->arm->cpsr->dirty = true;
633 dpm->arm->pc->dirty = true;
636 * re-evaluate the core state, we might be in Aarch32 state now
637 * we rely on dpm->dscr being up-to-date
639 core_state = armv8_dpm_get_core_state(dpm);
640 armv8_select_opcodes(armv8, core_state == ARM_STATE_AARCH64);
641 armv8_select_reg_access(armv8, core_state == ARM_STATE_AARCH64);
648 * Common register read, relies on armv8_select_reg_access() having been called.
650 static int dpmv8_read_reg(struct arm_dpm *dpm, struct reg *r, unsigned regnum)
652 struct armv8_common *armv8 = dpm->arm->arch_info;
653 int retval = ERROR_FAIL;
657 retval = armv8->read_reg_u64(armv8, regnum, &value_64);
659 if (retval == ERROR_OK) {
662 buf_set_u64(r->value, 0, r->size, value_64);
664 LOG_DEBUG("READ: %s, %16.8llx", r->name, (unsigned long long) value_64);
666 LOG_DEBUG("READ: %s, %8.8x", r->name, (unsigned int) value_64);
668 } else if (r->size <= 128) {
669 uint64_t lvalue = 0, hvalue = 0;
670 retval = armv8->read_reg_u128(armv8, regnum, &lvalue, &hvalue);
672 if (retval == ERROR_OK) {
676 buf_set_u64(r->value, 0, 64, lvalue);
677 buf_set_u64(r->value + 8, 0, r->size - 64, hvalue);
679 LOG_DEBUG("READ: %s, lvalue=%16.8llx", r->name, (unsigned long long) lvalue);
680 LOG_DEBUG("READ: %s, hvalue=%16.8llx", r->name, (unsigned long long) hvalue);
687 * Common register write, relies on armv8_select_reg_access() having been called.
689 static int dpmv8_write_reg(struct arm_dpm *dpm, struct reg *r, unsigned regnum)
691 struct armv8_common *armv8 = dpm->arm->arch_info;
692 int retval = ERROR_FAIL;
697 value_64 = buf_get_u64(r->value, 0, r->size);
698 retval = armv8->write_reg_u64(armv8, regnum, value_64);
700 if (retval == ERROR_OK) {
703 LOG_DEBUG("WRITE: %s, %16.8llx", r->name, (unsigned long long)value_64);
705 LOG_DEBUG("WRITE: %s, %8.8x", r->name, (unsigned int)value_64);
707 } else if (r->size <= 128) {
708 uint64_t lvalue, hvalue;
710 lvalue = buf_get_u64(r->value, 0, 64);
711 hvalue = buf_get_u64(r->value + 8, 0, r->size - 64);
712 retval = armv8->write_reg_u128(armv8, regnum, lvalue, hvalue);
714 if (retval == ERROR_OK) {
717 LOG_DEBUG("WRITE: %s, lvalue=%16.8llx", r->name, (unsigned long long) lvalue);
718 LOG_DEBUG("WRITE: %s, hvalue=%16.8llx", r->name, (unsigned long long) hvalue);
726 * Read basic registers of the the current context: R0 to R15, and CPSR;
727 * sets the core mode (such as USR or IRQ) and state (such as ARM or Thumb).
728 * In normal operation this is called on entry to halting debug state,
729 * possibly after some other operations supporting restore of debug state
730 * or making sure the CPU is fully idle (drain write buffer, etc).
732 int armv8_dpm_read_current_registers(struct arm_dpm *dpm)
734 struct arm *arm = dpm->arm;
735 struct armv8_common *armv8 = (struct armv8_common *)arm->arch_info;
736 struct reg_cache *cache;
741 retval = dpm->prepare(dpm);
742 if (retval != ERROR_OK)
745 cache = arm->core_cache;
747 /* read R0 first (it's used for scratch), then CPSR */
748 r = cache->reg_list + ARMV8_R0;
750 retval = dpmv8_read_reg(dpm, r, ARMV8_R0);
751 if (retval != ERROR_OK)
756 /* read R1, too, it will be clobbered during memory access */
757 r = cache->reg_list + ARMV8_R1;
759 retval = dpmv8_read_reg(dpm, r, ARMV8_R1);
760 if (retval != ERROR_OK)
764 /* read cpsr to r0 and get it back */
765 retval = dpm->instr_read_data_r0(dpm,
766 armv8_opcode(armv8, READ_REG_DSPSR), &cpsr);
767 if (retval != ERROR_OK)
770 /* update core mode and state */
771 armv8_set_cpsr(arm, cpsr);
773 for (unsigned int i = ARMV8_PC; i < cache->num_regs ; i++) {
774 struct arm_reg *arm_reg;
776 r = armv8_reg_current(arm, i);
780 /* Skip reading FP-SIMD registers */
781 if (r->number >= ARMV8_V0 && r->number <= ARMV8_FPCR)
785 * Only read registers that are available from the
786 * current EL (or core mode).
788 arm_reg = r->arch_info;
789 if (arm_reg->mode != ARM_MODE_ANY &&
790 dpm->last_el != armv8_curel_from_core_mode(arm_reg->mode))
793 retval = dpmv8_read_reg(dpm, r, i);
794 if (retval != ERROR_OK)
804 /* Avoid needless I/O ... leave breakpoints and watchpoints alone
805 * unless they're removed, or need updating because of single-stepping
806 * or running debugger code.
808 static int dpmv8_maybe_update_bpwp(struct arm_dpm *dpm, bool bpwp,
809 struct dpm_bpwp *xp, int *set_p)
811 int retval = ERROR_OK;
818 /* removed or startup; we must disable it */
823 /* disabled, but we must set it */
824 xp->dirty = disable = false;
829 /* set, but we must temporarily disable it */
830 xp->dirty = disable = true;
835 retval = dpm->bpwp_disable(dpm, xp->number);
837 retval = dpm->bpwp_enable(dpm, xp->number,
838 xp->address, xp->control);
840 if (retval != ERROR_OK)
841 LOG_ERROR("%s: can't %s HW %spoint %d",
842 disable ? "disable" : "enable",
843 target_name(dpm->arm->target),
844 (xp->number < 16) ? "break" : "watch",
850 static int dpmv8_add_breakpoint(struct target *target, struct breakpoint *bp);
853 * Writes all modified core registers for all processor modes. In normal
854 * operation this is called on exit from halting debug state.
856 * @param dpm: represents the processor
857 * @param bpwp: true ensures breakpoints and watchpoints are set,
858 * false ensures they are cleared
860 int armv8_dpm_write_dirty_registers(struct arm_dpm *dpm, bool bpwp)
862 struct arm *arm = dpm->arm;
863 struct reg_cache *cache = arm->core_cache;
866 retval = dpm->prepare(dpm);
867 if (retval != ERROR_OK)
870 /* If we're managing hardware breakpoints for this core, enable
871 * or disable them as requested.
873 * REVISIT We don't yet manage them for ANY cores. Eventually
874 * we should be able to assume we handle them; but until then,
875 * cope with the hand-crafted breakpoint code.
877 if (arm->target->type->add_breakpoint == dpmv8_add_breakpoint) {
878 for (unsigned i = 0; i < dpm->nbp; i++) {
879 struct dpm_bp *dbp = dpm->dbp + i;
880 struct breakpoint *bp = dbp->bp;
882 retval = dpmv8_maybe_update_bpwp(dpm, bpwp, &dbp->bpwp,
883 bp ? &bp->set : NULL);
884 if (retval != ERROR_OK)
889 /* enable/disable watchpoints */
890 for (unsigned i = 0; i < dpm->nwp; i++) {
891 struct dpm_wp *dwp = dpm->dwp + i;
892 struct watchpoint *wp = dwp->wp;
894 retval = dpmv8_maybe_update_bpwp(dpm, bpwp, &dwp->bpwp,
895 wp ? &wp->set : NULL);
896 if (retval != ERROR_OK)
900 /* NOTE: writes to breakpoint and watchpoint registers might
901 * be queued, and need (efficient/batched) flushing later.
904 /* Restore original core mode and state */
905 retval = armv8_dpm_modeswitch(dpm, ARM_MODE_ANY);
906 if (retval != ERROR_OK)
909 /* check everything except our scratch register R0 */
910 for (unsigned i = 1; i < cache->num_regs; i++) {
913 /* skip PC and CPSR */
914 if (i == ARMV8_PC || i == ARMV8_xPSR)
917 if (!cache->reg_list[i].valid)
920 if (!cache->reg_list[i].dirty)
923 /* skip all registers not on the current EL */
924 r = cache->reg_list[i].arch_info;
925 if (r->mode != ARM_MODE_ANY &&
926 dpm->last_el != armv8_curel_from_core_mode(r->mode))
929 retval = dpmv8_write_reg(dpm, &cache->reg_list[i], i);
930 if (retval != ERROR_OK)
934 /* flush CPSR and PC */
935 if (retval == ERROR_OK)
936 retval = dpmv8_write_reg(dpm, &cache->reg_list[ARMV8_xPSR], ARMV8_xPSR);
937 if (retval == ERROR_OK)
938 retval = dpmv8_write_reg(dpm, &cache->reg_list[ARMV8_PC], ARMV8_PC);
939 /* flush R0 -- it's *very* dirty by now */
940 if (retval == ERROR_OK)
941 retval = dpmv8_write_reg(dpm, &cache->reg_list[0], 0);
942 if (retval == ERROR_OK)
943 dpm->instr_cpsr_sync(dpm);
950 * Standard ARM register accessors ... there are three methods
951 * in "struct arm", to support individual read/write and bulk read
955 static int armv8_dpm_read_core_reg(struct target *target, struct reg *r,
956 int regnum, enum arm_mode mode)
958 struct arm *arm = target_to_arm(target);
959 struct arm_dpm *dpm = target_to_arm(target)->dpm;
961 int max = arm->core_cache->num_regs;
963 if (regnum < 0 || regnum >= max)
964 return ERROR_COMMAND_SYNTAX_ERROR;
967 * REVISIT what happens if we try to read SPSR in a core mode
968 * which has no such register?
970 retval = dpm->prepare(dpm);
971 if (retval != ERROR_OK)
974 retval = dpmv8_read_reg(dpm, r, regnum);
975 if (retval != ERROR_OK)
979 /* (void) */ dpm->finish(dpm);
983 static int armv8_dpm_write_core_reg(struct target *target, struct reg *r,
984 int regnum, enum arm_mode mode, uint8_t *value)
986 struct arm *arm = target_to_arm(target);
987 struct arm_dpm *dpm = target_to_arm(target)->dpm;
989 int max = arm->core_cache->num_regs;
991 if (regnum < 0 || regnum > max)
992 return ERROR_COMMAND_SYNTAX_ERROR;
994 /* REVISIT what happens if we try to write SPSR in a core mode
995 * which has no such register?
998 retval = dpm->prepare(dpm);
999 if (retval != ERROR_OK)
1002 retval = dpmv8_write_reg(dpm, r, regnum);
1004 /* always clean up, regardless of error */
1010 static int armv8_dpm_full_context(struct target *target)
1012 struct arm *arm = target_to_arm(target);
1013 struct arm_dpm *dpm = arm->dpm;
1014 struct reg_cache *cache = arm->core_cache;
1018 retval = dpm->prepare(dpm);
1019 if (retval != ERROR_OK)
1023 enum arm_mode mode = ARM_MODE_ANY;
1027 /* We "know" arm_dpm_read_current_registers() was called so
1028 * the unmapped registers (R0..R7, PC, AND CPSR) and some
1029 * view of R8..R14 are current. We also "know" oddities of
1030 * register mapping: special cases for R8..R12 and SPSR.
1032 * Pick some mode with unread registers and read them all.
1033 * Repeat until done.
1035 for (unsigned i = 0; i < cache->num_regs; i++) {
1038 if (cache->reg_list[i].valid)
1040 r = cache->reg_list[i].arch_info;
1042 /* may need to pick a mode and set CPSR */
1047 /* For regular (ARM_MODE_ANY) R8..R12
1048 * in case we've entered debug state
1049 * in FIQ mode we need to patch mode.
1051 if (mode != ARM_MODE_ANY)
1052 retval = armv8_dpm_modeswitch(dpm, mode);
1054 retval = armv8_dpm_modeswitch(dpm, ARM_MODE_USR);
1056 if (retval != ERROR_OK)
1059 if (r->mode != mode)
1062 /* CPSR was read, so "R16" must mean SPSR */
1063 retval = dpmv8_read_reg(dpm,
1064 &cache->reg_list[i],
1065 (r->num == 16) ? 17 : r->num);
1066 if (retval != ERROR_OK)
1072 retval = armv8_dpm_modeswitch(dpm, ARM_MODE_ANY);
1073 /* (void) */ dpm->finish(dpm);
1079 /*----------------------------------------------------------------------*/
1082 * Breakpoint and Watchpoint support.
1084 * Hardware {break,watch}points are usually left active, to minimize
1085 * debug entry/exit costs. When they are set or cleared, it's done in
1086 * batches. Also, DPM-conformant hardware can update debug registers
1087 * regardless of whether the CPU is running or halted ... though that
1088 * fact isn't currently leveraged.
1091 static int dpmv8_bpwp_setup(struct arm_dpm *dpm, struct dpm_bpwp *xp,
1092 uint32_t addr, uint32_t length)
1096 control = (1 << 0) /* enable */
1097 | (3 << 1); /* both user and privileged access */
1099 /* Match 1, 2, or all 4 byte addresses in this word.
1101 * FIXME: v7 hardware allows lengths up to 2 GB for BP and WP.
1102 * Support larger length, when addr is suitably aligned. In
1103 * particular, allow watchpoints on 8 byte "double" values.
1105 * REVISIT allow watchpoints on unaligned 2-bit values; and on
1106 * v7 hardware, unaligned 4-byte ones too.
1110 control |= (1 << (addr & 3)) << 5;
1113 /* require 2-byte alignment */
1115 control |= (3 << (addr & 2)) << 5;
1120 /* require 4-byte alignment */
1122 control |= 0xf << 5;
1127 LOG_ERROR("unsupported {break,watch}point length/alignment");
1128 return ERROR_COMMAND_SYNTAX_ERROR;
1131 /* other shared control bits:
1132 * bits 15:14 == 0 ... both secure and nonsecure states (v6.1+ only)
1133 * bit 20 == 0 ... not linked to a context ID
1134 * bit 28:24 == 0 ... not ignoring N LSBs (v7 only)
1137 xp->address = addr & ~3;
1138 xp->control = control;
1141 LOG_DEBUG("BPWP: addr %8.8" PRIx32 ", control %" PRIx32 ", number %d",
1142 xp->address, control, xp->number);
1144 /* hardware is updated in write_dirty_registers() */
1148 static int dpmv8_add_breakpoint(struct target *target, struct breakpoint *bp)
1150 struct arm *arm = target_to_arm(target);
1151 struct arm_dpm *dpm = arm->dpm;
1152 int retval = ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
1155 return ERROR_COMMAND_SYNTAX_ERROR;
1156 if (!dpm->bpwp_enable)
1159 /* FIXME we need a generic solution for software breakpoints. */
1160 if (bp->type == BKPT_SOFT)
1161 LOG_DEBUG("using HW bkpt, not SW...");
1163 for (unsigned i = 0; i < dpm->nbp; i++) {
1164 if (!dpm->dbp[i].bp) {
1165 retval = dpmv8_bpwp_setup(dpm, &dpm->dbp[i].bpwp,
1166 bp->address, bp->length);
1167 if (retval == ERROR_OK)
1168 dpm->dbp[i].bp = bp;
1176 static int dpmv8_remove_breakpoint(struct target *target, struct breakpoint *bp)
1178 struct arm *arm = target_to_arm(target);
1179 struct arm_dpm *dpm = arm->dpm;
1180 int retval = ERROR_COMMAND_SYNTAX_ERROR;
1182 for (unsigned i = 0; i < dpm->nbp; i++) {
1183 if (dpm->dbp[i].bp == bp) {
1184 dpm->dbp[i].bp = NULL;
1185 dpm->dbp[i].bpwp.dirty = true;
1187 /* hardware is updated in write_dirty_registers() */
1196 static int dpmv8_watchpoint_setup(struct arm_dpm *dpm, unsigned index_t,
1197 struct watchpoint *wp)
1200 struct dpm_wp *dwp = dpm->dwp + index_t;
1203 /* this hardware doesn't support data value matching or masking */
1204 if (wp->value || wp->mask != ~(uint32_t)0) {
1205 LOG_DEBUG("watchpoint values and masking not supported");
1206 return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
1209 retval = dpmv8_bpwp_setup(dpm, &dwp->bpwp, wp->address, wp->length);
1210 if (retval != ERROR_OK)
1213 control = dwp->bpwp.control;
1225 dwp->bpwp.control = control;
1227 dpm->dwp[index_t].wp = wp;
1232 static int dpmv8_add_watchpoint(struct target *target, struct watchpoint *wp)
1234 struct arm *arm = target_to_arm(target);
1235 struct arm_dpm *dpm = arm->dpm;
1236 int retval = ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
1238 if (dpm->bpwp_enable) {
1239 for (unsigned i = 0; i < dpm->nwp; i++) {
1240 if (!dpm->dwp[i].wp) {
1241 retval = dpmv8_watchpoint_setup(dpm, i, wp);
1250 static int dpmv8_remove_watchpoint(struct target *target, struct watchpoint *wp)
1252 struct arm *arm = target_to_arm(target);
1253 struct arm_dpm *dpm = arm->dpm;
1254 int retval = ERROR_COMMAND_SYNTAX_ERROR;
1256 for (unsigned i = 0; i < dpm->nwp; i++) {
1257 if (dpm->dwp[i].wp == wp) {
1258 dpm->dwp[i].wp = NULL;
1259 dpm->dwp[i].bpwp.dirty = true;
1261 /* hardware is updated in write_dirty_registers() */
1270 void armv8_dpm_report_wfar(struct arm_dpm *dpm, uint64_t addr)
1272 switch (dpm->arm->core_state) {
1274 case ARM_STATE_AARCH64:
1277 case ARM_STATE_THUMB:
1278 case ARM_STATE_THUMB_EE:
1281 case ARM_STATE_JAZELLE:
1285 LOG_DEBUG("Unknown core_state");
1292 * Handle exceptions taken in debug state. This happens mostly for memory
1293 * accesses that violated a MMU policy. Taking an exception while in debug
1294 * state clobbers certain state registers on the target exception level.
1295 * Just mark those registers dirty so that they get restored on resume.
1296 * This works both for Aarch32 and Aarch64 states.
1298 * This function must not perform any actions that trigger another exception
1299 * or a recursion will happen.
1301 void armv8_dpm_handle_exception(struct arm_dpm *dpm, bool do_restore)
1303 struct armv8_common *armv8 = dpm->arm->arch_info;
1304 struct reg_cache *cache = dpm->arm->core_cache;
1305 enum arm_state core_state;
1310 static const int clobbered_regs_by_el[3][5] = {
1311 { ARMV8_PC, ARMV8_xPSR, ARMV8_ELR_EL1, ARMV8_ESR_EL1, ARMV8_SPSR_EL1 },
1312 { ARMV8_PC, ARMV8_xPSR, ARMV8_ELR_EL2, ARMV8_ESR_EL2, ARMV8_SPSR_EL2 },
1313 { ARMV8_PC, ARMV8_xPSR, ARMV8_ELR_EL3, ARMV8_ESR_EL3, ARMV8_SPSR_EL3 },
1316 el = (dpm->dscr >> 8) & 3;
1318 /* safety check, must not happen since EL0 cannot be a target for an exception */
1319 if (el < SYSTEM_CUREL_EL1 || el > SYSTEM_CUREL_EL3) {
1320 LOG_ERROR("%s: EL %i is invalid, DSCR corrupted?", __func__, el);
1324 /* Clear sticky error */
1325 mem_ap_write_u32(armv8->debug_ap,
1326 armv8->debug_base + CPUV8_DBG_DRCR, DRCR_CSE);
1328 armv8->read_reg_u64(armv8, ARMV8_xPSR, &dlr);
1330 armv8->read_reg_u64(armv8, ARMV8_PC, &dlr);
1332 LOG_DEBUG("Exception taken to EL %i, DLR=0x%016"PRIx64" DSPSR=0x%08"PRIx32,
1335 /* mark all clobbered registers as dirty */
1336 for (int i = 0; i < 5; i++)
1337 cache->reg_list[clobbered_regs_by_el[el-1][i]].dirty = true;
1340 * re-evaluate the core state, we might be in Aarch64 state now
1341 * we rely on dpm->dscr being up-to-date
1343 core_state = armv8_dpm_get_core_state(dpm);
1344 armv8_select_opcodes(armv8, core_state == ARM_STATE_AARCH64);
1345 armv8_select_reg_access(armv8, core_state == ARM_STATE_AARCH64);
1348 armv8_dpm_modeswitch(dpm, ARM_MODE_ANY);
1351 /*----------------------------------------------------------------------*/
1354 * Other debug and support utilities
1357 void armv8_dpm_report_dscr(struct arm_dpm *dpm, uint32_t dscr)
1359 struct target *target = dpm->arm->target;
1362 dpm->last_el = (dscr >> 8) & 3;
1364 /* Examine debug reason */
1365 switch (DSCR_ENTRY(dscr)) {
1366 /* FALL THROUGH -- assume a v6 core in abort mode */
1367 case DSCRV8_ENTRY_EXT_DEBUG: /* EDBGRQ */
1368 target->debug_reason = DBG_REASON_DBGRQ;
1370 case DSCRV8_ENTRY_HALT_STEP_EXECLU: /* HALT step */
1371 case DSCRV8_ENTRY_HALT_STEP_NORMAL: /* Halt step*/
1372 case DSCRV8_ENTRY_HALT_STEP:
1373 target->debug_reason = DBG_REASON_SINGLESTEP;
1375 case DSCRV8_ENTRY_HLT: /* HLT instruction (software breakpoint) */
1376 case DSCRV8_ENTRY_BKPT: /* SW BKPT (?) */
1377 case DSCRV8_ENTRY_RESET_CATCH: /* Reset catch */
1378 case DSCRV8_ENTRY_OS_UNLOCK: /*OS unlock catch*/
1379 case DSCRV8_ENTRY_EXCEPTION_CATCH: /*exception catch*/
1380 case DSCRV8_ENTRY_SW_ACCESS_DBG: /*SW access dbg register*/
1381 target->debug_reason = DBG_REASON_BREAKPOINT;
1383 case DSCRV8_ENTRY_WATCHPOINT: /* asynch watchpoint */
1384 target->debug_reason = DBG_REASON_WATCHPOINT;
1387 target->debug_reason = DBG_REASON_UNDEFINED;
1393 /*----------------------------------------------------------------------*/
1396 * Setup and management support.
1400 * Hooks up this DPM to its associated target; call only once.
1401 * Initially this only covers the register cache.
1403 * Oh, and watchpoints. Yeah.
1405 int armv8_dpm_setup(struct arm_dpm *dpm)
1407 struct arm *arm = dpm->arm;
1408 struct target *target = arm->target;
1409 struct reg_cache *cache;
1412 /* register access setup */
1413 arm->full_context = armv8_dpm_full_context;
1414 arm->read_core_reg = armv8_dpm_read_core_reg;
1415 arm->write_core_reg = armv8_dpm_write_core_reg;
1417 if (arm->core_cache == NULL) {
1418 cache = armv8_build_reg_cache(target);
1423 /* coprocessor access setup */
1424 arm->mrc = dpmv8_mrc;
1425 arm->mcr = dpmv8_mcr;
1427 dpm->prepare = dpmv8_dpm_prepare;
1428 dpm->finish = dpmv8_dpm_finish;
1430 dpm->instr_execute = dpmv8_instr_execute;
1431 dpm->instr_write_data_dcc = dpmv8_instr_write_data_dcc;
1432 dpm->instr_write_data_dcc_64 = dpmv8_instr_write_data_dcc_64;
1433 dpm->instr_write_data_r0 = dpmv8_instr_write_data_r0;
1434 dpm->instr_write_data_r0_64 = dpmv8_instr_write_data_r0_64;
1435 dpm->instr_cpsr_sync = dpmv8_instr_cpsr_sync;
1437 dpm->instr_read_data_dcc = dpmv8_instr_read_data_dcc;
1438 dpm->instr_read_data_dcc_64 = dpmv8_instr_read_data_dcc_64;
1439 dpm->instr_read_data_r0 = dpmv8_instr_read_data_r0;
1440 dpm->instr_read_data_r0_64 = dpmv8_instr_read_data_r0_64;
1442 dpm->arm_reg_current = armv8_reg_current;
1444 /* dpm->bpwp_enable = dpmv8_bpwp_enable; */
1445 dpm->bpwp_disable = dpmv8_bpwp_disable;
1447 /* breakpoint setup -- optional until it works everywhere */
1448 if (!target->type->add_breakpoint) {
1449 target->type->add_breakpoint = dpmv8_add_breakpoint;
1450 target->type->remove_breakpoint = dpmv8_remove_breakpoint;
1453 /* watchpoint setup */
1454 target->type->add_watchpoint = dpmv8_add_watchpoint;
1455 target->type->remove_watchpoint = dpmv8_remove_watchpoint;
1457 /* FIXME add vector catch support */
1459 dpm->nbp = 1 + ((dpm->didr >> 12) & 0xf);
1460 dpm->dbp = calloc(dpm->nbp, sizeof *dpm->dbp);
1462 dpm->nwp = 1 + ((dpm->didr >> 20) & 0xf);
1463 dpm->dwp = calloc(dpm->nwp, sizeof *dpm->dwp);
1465 if (!dpm->dbp || !dpm->dwp) {
1471 LOG_INFO("%s: hardware has %d breakpoints, %d watchpoints",
1472 target_name(target), dpm->nbp, dpm->nwp);
1474 /* REVISIT ... and some of those breakpoints could match
1475 * execution context IDs...
1482 * Reinitializes DPM state at the beginning of a new debug session
1483 * or after a reset which may have affected the debug module.
1485 int armv8_dpm_initialize(struct arm_dpm *dpm)
1487 /* Disable all breakpoints and watchpoints at startup. */
1488 if (dpm->bpwp_disable) {
1491 for (i = 0; i < dpm->nbp; i++) {
1492 dpm->dbp[i].bpwp.number = i;
1493 (void) dpm->bpwp_disable(dpm, i);
1495 for (i = 0; i < dpm->nwp; i++) {
1496 dpm->dwp[i].bpwp.number = 16 + i;
1497 (void) dpm->bpwp_disable(dpm, 16 + i);
1500 LOG_WARNING("%s: can't disable breakpoints and watchpoints",
1501 target_name(dpm->arm->target));