aarch64: support for aarch32 ARM_MODE_SYS
[fw/openocd] / src / target / armv8_dpm.c
1 /*
2  * Copyright (C) 2009 by David Brownell
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation; either version 2 of the License, or
7  * (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  */
15
16 #ifdef HAVE_CONFIG_H
17 #include "config.h"
18 #endif
19
20 #include "arm.h"
21 #include "armv8.h"
22 #include "armv8_dpm.h"
23 #include <jtag/jtag.h>
24 #include "register.h"
25 #include "breakpoints.h"
26 #include "target_type.h"
27 #include "armv8_opcodes.h"
28
29 #include "helper/time_support.h"
30
31 /* T32 ITR format */
32 #define T32_FMTITR(instr) (((instr & 0x0000FFFF) << 16) | ((instr & 0xFFFF0000) >> 16))
33
34 /**
35  * @file
36  * Implements various ARM DPM operations using architectural debug registers.
37  * These routines layer over core-specific communication methods to cope with
38  * implementation differences between cores like ARM1136 and Cortex-A8.
39  *
40  * The "Debug Programmers' Model" (DPM) for ARMv6 and ARMv7 is defined by
41  * Part C (Debug Architecture) of the ARM Architecture Reference Manual,
42  * ARMv7-A and ARMv7-R edition (ARM DDI 0406B).  In OpenOCD, DPM operations
43  * are abstracted through internal programming interfaces to share code and
44  * to minimize needless differences in debug behavior between cores.
45  */
46
47 /**
48  * Get core state from EDSCR, without necessity to retrieve CPSR
49  */
50 enum arm_state armv8_dpm_get_core_state(struct arm_dpm *dpm)
51 {
52         int el = (dpm->dscr >> 8) & 0x3;
53         int rw = (dpm->dscr >> 10) & 0xF;
54
55         dpm->last_el = el;
56
57         /* In Debug state, each bit gives the current Execution state of each EL */
58         if ((rw >> el) & 0b1)
59                 return ARM_STATE_AARCH64;
60
61         return ARM_STATE_ARM;
62 }
63
64 /*----------------------------------------------------------------------*/
65
66 static int dpmv8_write_dcc(struct armv8_common *armv8, uint32_t data)
67 {
68         return mem_ap_write_u32(armv8->debug_ap,
69                                 armv8->debug_base + CPUV8_DBG_DTRRX, data);
70 }
71
72 static int dpmv8_write_dcc_64(struct armv8_common *armv8, uint64_t data)
73 {
74         int ret;
75         ret = mem_ap_write_u32(armv8->debug_ap,
76                                armv8->debug_base + CPUV8_DBG_DTRRX, data);
77         if (ret == ERROR_OK)
78                 ret = mem_ap_write_u32(armv8->debug_ap,
79                                 armv8->debug_base + CPUV8_DBG_DTRTX, data >> 32);
80         return ret;
81 }
82
83 static int dpmv8_read_dcc(struct armv8_common *armv8, uint32_t *data,
84         uint32_t *dscr_p)
85 {
86         uint32_t dscr = DSCR_ITE;
87         int retval;
88
89         if (dscr_p)
90                 dscr = *dscr_p;
91
92         /* Wait for DTRRXfull */
93         long long then = timeval_ms();
94         while ((dscr & DSCR_DTR_TX_FULL) == 0) {
95                 retval = mem_ap_read_atomic_u32(armv8->debug_ap,
96                                 armv8->debug_base + CPUV8_DBG_DSCR,
97                                 &dscr);
98                 if (retval != ERROR_OK)
99                         return retval;
100                 if (timeval_ms() > then + 1000) {
101                         LOG_ERROR("Timeout waiting for read dcc");
102                         return ERROR_FAIL;
103                 }
104         }
105
106         retval = mem_ap_read_atomic_u32(armv8->debug_ap,
107                                             armv8->debug_base + CPUV8_DBG_DTRTX,
108                                             data);
109         if (retval != ERROR_OK)
110                 return retval;
111
112         if (dscr_p)
113                 *dscr_p = dscr;
114
115         return retval;
116 }
117
118 static int dpmv8_read_dcc_64(struct armv8_common *armv8, uint64_t *data,
119         uint32_t *dscr_p)
120 {
121         uint32_t dscr = DSCR_ITE;
122         uint32_t higher;
123         int retval;
124
125         if (dscr_p)
126                 dscr = *dscr_p;
127
128         /* Wait for DTRRXfull */
129         long long then = timeval_ms();
130         while ((dscr & DSCR_DTR_TX_FULL) == 0) {
131                 retval = mem_ap_read_atomic_u32(armv8->debug_ap,
132                                 armv8->debug_base + CPUV8_DBG_DSCR,
133                                 &dscr);
134                 if (retval != ERROR_OK)
135                         return retval;
136                 if (timeval_ms() > then + 1000) {
137                         LOG_ERROR("Timeout waiting for DTR_TX_FULL, dscr = 0x%08" PRIx32, dscr);
138                         return ERROR_FAIL;
139                 }
140         }
141
142         retval = mem_ap_read_atomic_u32(armv8->debug_ap,
143                                             armv8->debug_base + CPUV8_DBG_DTRTX,
144                                             (uint32_t *)data);
145         if (retval != ERROR_OK)
146                 return retval;
147
148         retval = mem_ap_read_atomic_u32(armv8->debug_ap,
149                                             armv8->debug_base + CPUV8_DBG_DTRRX,
150                                             &higher);
151         if (retval != ERROR_OK)
152                 return retval;
153
154         *data = *(uint32_t *)data | (uint64_t)higher << 32;
155
156         if (dscr_p)
157                 *dscr_p = dscr;
158
159         return retval;
160 }
161
162 static int dpmv8_dpm_prepare(struct arm_dpm *dpm)
163 {
164         struct armv8_common *armv8 = dpm->arm->arch_info;
165         uint32_t dscr;
166         int retval;
167
168         /* set up invariant:  ITE is set after ever DPM operation */
169         long long then = timeval_ms();
170         for (;; ) {
171                 retval = mem_ap_read_atomic_u32(armv8->debug_ap,
172                                 armv8->debug_base + CPUV8_DBG_DSCR,
173                                 &dscr);
174                 if (retval != ERROR_OK)
175                         return retval;
176                 if ((dscr & DSCR_ITE) != 0)
177                         break;
178                 if (timeval_ms() > then + 1000) {
179                         LOG_ERROR("Timeout waiting for dpm prepare");
180                         return ERROR_FAIL;
181                 }
182         }
183
184         /* update the stored copy of dscr */
185         dpm->dscr = dscr;
186
187         /* this "should never happen" ... */
188         if (dscr & DSCR_DTR_RX_FULL) {
189                 LOG_ERROR("DSCR_DTR_RX_FULL, dscr 0x%08" PRIx32, dscr);
190                 /* Clear DCCRX */
191                 retval = mem_ap_read_u32(armv8->debug_ap,
192                         armv8->debug_base + CPUV8_DBG_DTRRX, &dscr);
193                 if (retval != ERROR_OK)
194                         return retval;
195         }
196
197         return retval;
198 }
199
200 static int dpmv8_dpm_finish(struct arm_dpm *dpm)
201 {
202         /* REVISIT what could be done here? */
203         return ERROR_OK;
204 }
205
206 static int dpmv8_exec_opcode(struct arm_dpm *dpm,
207         uint32_t opcode, uint32_t *p_dscr)
208 {
209         struct armv8_common *armv8 = dpm->arm->arch_info;
210         uint32_t dscr = dpm->dscr;
211         int retval;
212
213         if (p_dscr)
214                 dscr = *p_dscr;
215
216         /* Wait for InstrCompl bit to be set */
217         long long then = timeval_ms();
218         while ((dscr & DSCR_ITE) == 0) {
219                 retval = mem_ap_read_atomic_u32(armv8->debug_ap,
220                                 armv8->debug_base + CPUV8_DBG_DSCR, &dscr);
221                 if (retval != ERROR_OK) {
222                         LOG_ERROR("Could not read DSCR register, opcode = 0x%08" PRIx32, opcode);
223                         return retval;
224                 }
225                 if (timeval_ms() > then + 1000) {
226                         LOG_ERROR("Timeout waiting for aarch64_exec_opcode");
227                         return ERROR_FAIL;
228                 }
229         }
230
231         if (armv8_dpm_get_core_state(dpm) != ARM_STATE_AARCH64)
232                 opcode = T32_FMTITR(opcode);
233
234         retval = mem_ap_write_u32(armv8->debug_ap,
235                         armv8->debug_base + CPUV8_DBG_ITR, opcode);
236         if (retval != ERROR_OK)
237                 return retval;
238
239         then = timeval_ms();
240         do {
241                 retval = mem_ap_read_atomic_u32(armv8->debug_ap,
242                                 armv8->debug_base + CPUV8_DBG_DSCR, &dscr);
243                 if (retval != ERROR_OK) {
244                         LOG_ERROR("Could not read DSCR register");
245                         return retval;
246                 }
247                 if (timeval_ms() > then + 1000) {
248                         LOG_ERROR("Timeout waiting for aarch64_exec_opcode");
249                         return ERROR_FAIL;
250                 }
251         } while ((dscr & DSCR_ITE) == 0);       /* Wait for InstrCompl bit to be set */
252
253         /* update dscr and el after each command execution */
254         dpm->dscr = dscr;
255         if (dpm->last_el != ((dscr >> 8) & 3))
256                 LOG_DEBUG("EL %i -> %i", dpm->last_el, (dscr >> 8) & 3);
257         dpm->last_el = (dscr >> 8) & 3;
258
259         if (dscr & DSCR_ERR) {
260                 LOG_ERROR("Opcode 0x%08"PRIx32", DSCR.ERR=1, DSCR.EL=%i", opcode, dpm->last_el);
261                 armv8_dpm_handle_exception(dpm, true);
262                 retval = ERROR_FAIL;
263         }
264
265         if (p_dscr)
266                 *p_dscr = dscr;
267
268         return retval;
269 }
270
271 static int dpmv8_instr_execute(struct arm_dpm *dpm, uint32_t opcode)
272 {
273         return dpmv8_exec_opcode(dpm, opcode, NULL);
274 }
275
276 static int dpmv8_instr_write_data_dcc(struct arm_dpm *dpm,
277         uint32_t opcode, uint32_t data)
278 {
279         struct armv8_common *armv8 = dpm->arm->arch_info;
280         int retval;
281
282         retval = dpmv8_write_dcc(armv8, data);
283         if (retval != ERROR_OK)
284                 return retval;
285
286         return dpmv8_exec_opcode(dpm, opcode, 0);
287 }
288
289 static int dpmv8_instr_write_data_dcc_64(struct arm_dpm *dpm,
290         uint32_t opcode, uint64_t data)
291 {
292         struct armv8_common *armv8 = dpm->arm->arch_info;
293         int retval;
294
295         retval = dpmv8_write_dcc_64(armv8, data);
296         if (retval != ERROR_OK)
297                 return retval;
298
299         return dpmv8_exec_opcode(dpm, opcode, 0);
300 }
301
302 static int dpmv8_instr_write_data_r0(struct arm_dpm *dpm,
303         uint32_t opcode, uint32_t data)
304 {
305         struct armv8_common *armv8 = dpm->arm->arch_info;
306         uint32_t dscr = DSCR_ITE;
307         int retval;
308
309         retval = dpmv8_write_dcc(armv8, data);
310         if (retval != ERROR_OK)
311                 return retval;
312
313         retval = dpmv8_exec_opcode(dpm, armv8_opcode(armv8, READ_REG_DTRRX), &dscr);
314         if (retval != ERROR_OK)
315                 return retval;
316
317         /* then the opcode, taking data from R0 */
318         return dpmv8_exec_opcode(dpm, opcode, &dscr);
319 }
320
321 static int dpmv8_instr_write_data_r0_64(struct arm_dpm *dpm,
322         uint32_t opcode, uint64_t data)
323 {
324         struct armv8_common *armv8 = dpm->arm->arch_info;
325         int retval;
326
327         if (dpm->arm->core_state != ARM_STATE_AARCH64)
328                 return dpmv8_instr_write_data_r0(dpm, opcode, data);
329
330         /* transfer data from DCC to R0 */
331         retval = dpmv8_write_dcc_64(armv8, data);
332         if (retval == ERROR_OK)
333                 retval = dpmv8_exec_opcode(dpm, ARMV8_MRS(SYSTEM_DBG_DBGDTR_EL0, 0), &dpm->dscr);
334
335         /* then the opcode, taking data from R0 */
336         if (retval == ERROR_OK)
337                 retval = dpmv8_exec_opcode(dpm, opcode, &dpm->dscr);
338
339         return retval;
340 }
341
342 static int dpmv8_instr_cpsr_sync(struct arm_dpm *dpm)
343 {
344         int retval;
345         struct armv8_common *armv8 = dpm->arm->arch_info;
346
347         /* "Prefetch flush" after modifying execution status in CPSR */
348         retval = dpmv8_exec_opcode(dpm, armv8_opcode(armv8, ARMV8_OPC_DSB_SY), &dpm->dscr);
349         if (retval == ERROR_OK)
350                 dpmv8_exec_opcode(dpm, armv8_opcode(armv8, ARMV8_OPC_ISB_SY), &dpm->dscr);
351         return retval;
352 }
353
354 static int dpmv8_instr_read_data_dcc(struct arm_dpm *dpm,
355         uint32_t opcode, uint32_t *data)
356 {
357         struct armv8_common *armv8 = dpm->arm->arch_info;
358         int retval;
359
360         /* the opcode, writing data to DCC */
361         retval = dpmv8_exec_opcode(dpm, opcode, &dpm->dscr);
362         if (retval != ERROR_OK)
363                 return retval;
364
365         return dpmv8_read_dcc(armv8, data, &dpm->dscr);
366 }
367
368 static int dpmv8_instr_read_data_dcc_64(struct arm_dpm *dpm,
369         uint32_t opcode, uint64_t *data)
370 {
371         struct armv8_common *armv8 = dpm->arm->arch_info;
372         int retval;
373
374         /* the opcode, writing data to DCC */
375         retval = dpmv8_exec_opcode(dpm, opcode, &dpm->dscr);
376         if (retval != ERROR_OK)
377                 return retval;
378
379         return dpmv8_read_dcc_64(armv8, data, &dpm->dscr);
380 }
381
382 static int dpmv8_instr_read_data_r0(struct arm_dpm *dpm,
383         uint32_t opcode, uint32_t *data)
384 {
385         struct armv8_common *armv8 = dpm->arm->arch_info;
386         int retval;
387
388         /* the opcode, writing data to R0 */
389         retval = dpmv8_exec_opcode(dpm, opcode, &dpm->dscr);
390         if (retval != ERROR_OK)
391                 return retval;
392
393         /* write R0 to DCC */
394         retval = dpmv8_exec_opcode(dpm, armv8_opcode(armv8, WRITE_REG_DTRTX), &dpm->dscr);
395         if (retval != ERROR_OK)
396                 return retval;
397
398         return dpmv8_read_dcc(armv8, data, &dpm->dscr);
399 }
400
401 static int dpmv8_instr_read_data_r0_64(struct arm_dpm *dpm,
402         uint32_t opcode, uint64_t *data)
403 {
404         struct armv8_common *armv8 = dpm->arm->arch_info;
405         int retval;
406
407         if (dpm->arm->core_state != ARM_STATE_AARCH64) {
408                 uint32_t tmp;
409                 retval = dpmv8_instr_read_data_r0(dpm, opcode, &tmp);
410                 if (retval == ERROR_OK)
411                         *data = tmp;
412                 return retval;
413         }
414
415         /* the opcode, writing data to R0 */
416         retval = dpmv8_exec_opcode(dpm, opcode, &dpm->dscr);
417         if (retval != ERROR_OK)
418                 return retval;
419
420         /* write R0 to DCC */
421         retval = dpmv8_exec_opcode(dpm, ARMV8_MSR_GP(SYSTEM_DBG_DBGDTR_EL0, 0), &dpm->dscr);
422         if (retval != ERROR_OK)
423                 return retval;
424
425         return dpmv8_read_dcc_64(armv8, data, &dpm->dscr);
426 }
427
428 #if 0
429 static int dpmv8_bpwp_enable(struct arm_dpm *dpm, unsigned index_t,
430         target_addr_t addr, uint32_t control)
431 {
432         struct armv8_common *armv8 = dpm->arm->arch_info;
433         uint32_t vr = armv8->debug_base;
434         uint32_t cr = armv8->debug_base;
435         int retval;
436
437         switch (index_t) {
438                 case 0 ... 15:  /* breakpoints */
439                         vr += CPUV8_DBG_BVR_BASE;
440                         cr += CPUV8_DBG_BCR_BASE;
441                         break;
442                 case 16 ... 31: /* watchpoints */
443                         vr += CPUV8_DBG_WVR_BASE;
444                         cr += CPUV8_DBG_WCR_BASE;
445                         index_t -= 16;
446                         break;
447                 default:
448                         return ERROR_FAIL;
449         }
450         vr += 16 * index_t;
451         cr += 16 * index_t;
452
453         LOG_DEBUG("A8: bpwp enable, vr %08x cr %08x",
454                 (unsigned) vr, (unsigned) cr);
455
456         retval = mem_ap_write_atomic_u32(armv8->debug_ap, vr, addr);
457         if (retval != ERROR_OK)
458                 return retval;
459         return mem_ap_write_atomic_u32(armv8->debug_ap, cr, control);
460 }
461 #endif
462
463 static int dpmv8_bpwp_disable(struct arm_dpm *dpm, unsigned index_t)
464 {
465         struct armv8_common *armv8 = dpm->arm->arch_info;
466         uint32_t cr;
467
468         switch (index_t) {
469                 case 0 ... 15:
470                         cr = armv8->debug_base + CPUV8_DBG_BCR_BASE;
471                         break;
472                 case 16 ... 31:
473                         cr = armv8->debug_base + CPUV8_DBG_WCR_BASE;
474                         index_t -= 16;
475                         break;
476                 default:
477                         return ERROR_FAIL;
478         }
479         cr += 16 * index_t;
480
481         LOG_DEBUG("A: bpwp disable, cr %08x", (unsigned) cr);
482
483         /* clear control register */
484         return mem_ap_write_atomic_u32(armv8->debug_ap, cr, 0);
485 }
486
487 /*
488  * Coprocessor support
489  */
490
491 /* Read coprocessor */
492 static int dpmv8_mrc(struct target *target, int cpnum,
493         uint32_t op1, uint32_t op2, uint32_t CRn, uint32_t CRm,
494         uint32_t *value)
495 {
496         struct arm *arm = target_to_arm(target);
497         struct arm_dpm *dpm = arm->dpm;
498         int retval;
499
500         retval = dpm->prepare(dpm);
501         if (retval != ERROR_OK)
502                 return retval;
503
504         LOG_DEBUG("MRC p%d, %d, r0, c%d, c%d, %d", cpnum,
505                 (int) op1, (int) CRn,
506                 (int) CRm, (int) op2);
507
508         /* read coprocessor register into R0; return via DCC */
509         retval = dpm->instr_read_data_r0(dpm,
510                         ARMV4_5_MRC(cpnum, op1, 0, CRn, CRm, op2),
511                         value);
512
513         /* (void) */ dpm->finish(dpm);
514         return retval;
515 }
516
517 static int dpmv8_mcr(struct target *target, int cpnum,
518         uint32_t op1, uint32_t op2, uint32_t CRn, uint32_t CRm,
519         uint32_t value)
520 {
521         struct arm *arm = target_to_arm(target);
522         struct arm_dpm *dpm = arm->dpm;
523         int retval;
524
525         retval = dpm->prepare(dpm);
526         if (retval != ERROR_OK)
527                 return retval;
528
529         LOG_DEBUG("MCR p%d, %d, r0, c%d, c%d, %d", cpnum,
530                 (int) op1, (int) CRn,
531                 (int) CRm, (int) op2);
532
533         /* read DCC into r0; then write coprocessor register from R0 */
534         retval = dpm->instr_write_data_r0(dpm,
535                         ARMV4_5_MCR(cpnum, op1, 0, CRn, CRm, op2),
536                         value);
537
538         /* (void) */ dpm->finish(dpm);
539         return retval;
540 }
541
542 /*----------------------------------------------------------------------*/
543
544 /*
545  * Register access utilities
546  */
547
548 int armv8_dpm_modeswitch(struct arm_dpm *dpm, enum arm_mode mode)
549 {
550         struct armv8_common *armv8 = (struct armv8_common *)dpm->arm->arch_info;
551         int retval = ERROR_OK;
552         unsigned int target_el;
553         enum arm_state core_state;
554         uint32_t cpsr;
555
556         /* restore previous mode */
557         if (mode == ARM_MODE_ANY) {
558                 cpsr = buf_get_u32(dpm->arm->cpsr->value, 0, 32);
559
560                 LOG_DEBUG("restoring mode, cpsr = 0x%08"PRIx32, cpsr);
561
562         } else {
563                 LOG_DEBUG("setting mode 0x%"PRIx32, mode);
564                 cpsr = mode;
565         }
566
567         switch (cpsr & 0x1f) {
568         /* aarch32 modes */
569         case ARM_MODE_USR:
570                 target_el = 0;
571                 break;
572         case ARM_MODE_SVC:
573         case ARM_MODE_ABT:
574         case ARM_MODE_IRQ:
575         case ARM_MODE_FIQ:
576         case ARM_MODE_SYS:
577                 target_el = 1;
578                 break;
579         /*
580          * TODO: handle ARM_MODE_HYP
581          * case ARM_MODE_HYP:
582          *      target_el = 2;
583          *      break;
584          */
585         case ARM_MODE_MON:
586                 target_el = 3;
587                 break;
588         /* aarch64 modes */
589         default:
590                 target_el = (cpsr >> 2) & 3;
591         }
592
593         if (target_el > SYSTEM_CUREL_EL3) {
594                 LOG_ERROR("%s: Invalid target exception level %i", __func__, target_el);
595                 return ERROR_FAIL;
596         }
597
598         LOG_DEBUG("target_el = %i, last_el = %i", target_el, dpm->last_el);
599         if (target_el > dpm->last_el) {
600                 retval = dpm->instr_execute(dpm,
601                                 armv8_opcode(armv8, ARMV8_OPC_DCPS) | target_el);
602
603                 /* DCPS clobbers registers just like an exception taken */
604                 armv8_dpm_handle_exception(dpm, false);
605         } else {
606                 core_state = armv8_dpm_get_core_state(dpm);
607                 if (core_state != ARM_STATE_AARCH64) {
608                         /* cannot do DRPS/ERET when already in EL0 */
609                         if (dpm->last_el != 0) {
610                                 /* load SPSR with the desired mode and execute DRPS */
611                                 LOG_DEBUG("SPSR = 0x%08"PRIx32, cpsr);
612                                 retval = dpm->instr_write_data_r0(dpm,
613                                                 ARMV8_MSR_GP_xPSR_T1(1, 0, 15), cpsr);
614                                 if (retval == ERROR_OK)
615                                         retval = dpm->instr_execute(dpm, armv8_opcode(armv8, ARMV8_OPC_DRPS));
616                         }
617                 } else {
618                         /*
619                          * need to execute multiple DRPS instructions until target_el
620                          * is reached
621                          */
622                         while (retval == ERROR_OK && dpm->last_el != target_el) {
623                                 unsigned int cur_el = dpm->last_el;
624                                 retval = dpm->instr_execute(dpm, armv8_opcode(armv8, ARMV8_OPC_DRPS));
625                                 if (cur_el == dpm->last_el) {
626                                         LOG_INFO("Cannot reach EL %i, SPSR corrupted?", target_el);
627                                         break;
628                                 }
629                         }
630                 }
631
632                 /* On executing DRPS, DSPSR and DLR become UNKNOWN, mark them as dirty */
633                 dpm->arm->cpsr->dirty = true;
634                 dpm->arm->pc->dirty = true;
635
636                 /*
637                  * re-evaluate the core state, we might be in Aarch32 state now
638                  * we rely on dpm->dscr being up-to-date
639                  */
640                 core_state = armv8_dpm_get_core_state(dpm);
641                 armv8_select_opcodes(armv8, core_state == ARM_STATE_AARCH64);
642                 armv8_select_reg_access(armv8, core_state == ARM_STATE_AARCH64);
643         }
644
645         return retval;
646 }
647
648 /*
649  * Common register read, relies on armv8_select_reg_access() having been called.
650  */
651 static int dpmv8_read_reg(struct arm_dpm *dpm, struct reg *r, unsigned regnum)
652 {
653         struct armv8_common *armv8 = dpm->arm->arch_info;
654         int retval = ERROR_FAIL;
655
656         if (r->size <= 64) {
657                 uint64_t value_64;
658                 retval = armv8->read_reg_u64(armv8, regnum, &value_64);
659
660                 if (retval == ERROR_OK) {
661                         r->valid = true;
662                         r->dirty = false;
663                         buf_set_u64(r->value, 0, r->size, value_64);
664                         if (r->size == 64)
665                                 LOG_DEBUG("READ: %s, %16.8llx", r->name, (unsigned long long) value_64);
666                         else
667                                 LOG_DEBUG("READ: %s, %8.8x", r->name, (unsigned int) value_64);
668                 }
669         } else if (r->size <= 128) {
670                 uint64_t lvalue = 0, hvalue = 0;
671                 retval = armv8->read_reg_u128(armv8, regnum, &lvalue, &hvalue);
672
673                 if (retval == ERROR_OK) {
674                         r->valid = true;
675                         r->dirty = false;
676
677                         buf_set_u64(r->value, 0, 64, lvalue);
678                         buf_set_u64(r->value + 8, 0, r->size - 64, hvalue);
679
680                         LOG_DEBUG("READ: %s, lvalue=%16.8llx", r->name, (unsigned long long) lvalue);
681                         LOG_DEBUG("READ: %s, hvalue=%16.8llx", r->name, (unsigned long long) hvalue);
682                 }
683         }
684         return retval;
685 }
686
687 /*
688  * Common register write, relies on armv8_select_reg_access() having been called.
689  */
690 static int dpmv8_write_reg(struct arm_dpm *dpm, struct reg *r, unsigned regnum)
691 {
692         struct armv8_common *armv8 = dpm->arm->arch_info;
693         int retval = ERROR_FAIL;
694
695         if (r->size <= 64) {
696                 uint64_t value_64;
697
698                 value_64 = buf_get_u64(r->value, 0, r->size);
699                 retval = armv8->write_reg_u64(armv8, regnum, value_64);
700
701                 if (retval == ERROR_OK) {
702                         r->dirty = false;
703                         if (r->size == 64)
704                                 LOG_DEBUG("WRITE: %s, %16.8llx", r->name, (unsigned long long)value_64);
705                         else
706                                 LOG_DEBUG("WRITE: %s, %8.8x", r->name, (unsigned int)value_64);
707                 }
708         } else if (r->size <= 128) {
709                 uint64_t lvalue, hvalue;
710
711                 lvalue = buf_get_u64(r->value, 0, 64);
712                 hvalue = buf_get_u64(r->value + 8, 0, r->size - 64);
713                 retval = armv8->write_reg_u128(armv8, regnum, lvalue, hvalue);
714
715                 if (retval == ERROR_OK) {
716                         r->dirty = false;
717
718                         LOG_DEBUG("WRITE: %s, lvalue=%16.8llx", r->name, (unsigned long long) lvalue);
719                         LOG_DEBUG("WRITE: %s, hvalue=%16.8llx", r->name, (unsigned long long) hvalue);
720                 }
721         }
722
723         return retval;
724 }
725
726 /**
727  * Read basic registers of the the current context:  R0 to R15, and CPSR;
728  * sets the core mode (such as USR or IRQ) and state (such as ARM or Thumb).
729  * In normal operation this is called on entry to halting debug state,
730  * possibly after some other operations supporting restore of debug state
731  * or making sure the CPU is fully idle (drain write buffer, etc).
732  */
733 int armv8_dpm_read_current_registers(struct arm_dpm *dpm)
734 {
735         struct arm *arm = dpm->arm;
736         struct armv8_common *armv8 = (struct armv8_common *)arm->arch_info;
737         struct reg_cache *cache;
738         struct reg *r;
739         uint32_t cpsr;
740         int retval;
741
742         retval = dpm->prepare(dpm);
743         if (retval != ERROR_OK)
744                 return retval;
745
746         cache = arm->core_cache;
747
748         /* read R0 first (it's used for scratch), then CPSR */
749         r = cache->reg_list + ARMV8_R0;
750         if (!r->valid) {
751                 retval = dpmv8_read_reg(dpm, r, ARMV8_R0);
752                 if (retval != ERROR_OK)
753                         goto fail;
754         }
755         r->dirty = true;
756
757         /* read R1, too, it will be clobbered during memory access */
758         r = cache->reg_list + ARMV8_R1;
759         if (!r->valid) {
760                 retval = dpmv8_read_reg(dpm, r, ARMV8_R1);
761                 if (retval != ERROR_OK)
762                         goto fail;
763         }
764
765         /* read cpsr to r0 and get it back */
766         retval = dpm->instr_read_data_r0(dpm,
767                         armv8_opcode(armv8, READ_REG_DSPSR), &cpsr);
768         if (retval != ERROR_OK)
769                 goto fail;
770
771         /* update core mode and state */
772         armv8_set_cpsr(arm, cpsr);
773
774         for (unsigned int i = ARMV8_PC; i < cache->num_regs ; i++) {
775                 struct arm_reg *arm_reg;
776
777                 r = armv8_reg_current(arm, i);
778                 if (r->valid)
779                         continue;
780
781                 /* Skip reading FP-SIMD registers */
782                 if (r->number >= ARMV8_V0 && r->number <= ARMV8_FPCR)
783                         continue;
784
785                 /*
786                  * Only read registers that are available from the
787                  * current EL (or core mode).
788                  */
789                 arm_reg = r->arch_info;
790                 if (arm_reg->mode != ARM_MODE_ANY &&
791                                 dpm->last_el != armv8_curel_from_core_mode(arm_reg->mode))
792                         continue;
793
794                 /* Special case: ARM_MODE_SYS has no SPSR at EL1 */
795                 if (r->number == ARMV8_SPSR_EL1 && arm->core_mode == ARM_MODE_SYS)
796                         continue;
797
798                 retval = dpmv8_read_reg(dpm, r, i);
799                 if (retval != ERROR_OK)
800                         goto fail;
801
802         }
803
804 fail:
805         dpm->finish(dpm);
806         return retval;
807 }
808
809 /* Avoid needless I/O ... leave breakpoints and watchpoints alone
810  * unless they're removed, or need updating because of single-stepping
811  * or running debugger code.
812  */
813 static int dpmv8_maybe_update_bpwp(struct arm_dpm *dpm, bool bpwp,
814         struct dpm_bpwp *xp, int *set_p)
815 {
816         int retval = ERROR_OK;
817         bool disable;
818
819         if (!set_p) {
820                 if (!xp->dirty)
821                         goto done;
822                 xp->dirty = false;
823                 /* removed or startup; we must disable it */
824                 disable = true;
825         } else if (bpwp) {
826                 if (!xp->dirty)
827                         goto done;
828                 /* disabled, but we must set it */
829                 xp->dirty = disable = false;
830                 *set_p = true;
831         } else {
832                 if (!*set_p)
833                         goto done;
834                 /* set, but we must temporarily disable it */
835                 xp->dirty = disable = true;
836                 *set_p = false;
837         }
838
839         if (disable)
840                 retval = dpm->bpwp_disable(dpm, xp->number);
841         else
842                 retval = dpm->bpwp_enable(dpm, xp->number,
843                                 xp->address, xp->control);
844
845         if (retval != ERROR_OK)
846                 LOG_ERROR("%s: can't %s HW %spoint %d",
847                         disable ? "disable" : "enable",
848                         target_name(dpm->arm->target),
849                         (xp->number < 16) ? "break" : "watch",
850                         xp->number & 0xf);
851 done:
852         return retval;
853 }
854
855 static int dpmv8_add_breakpoint(struct target *target, struct breakpoint *bp);
856
857 /**
858  * Writes all modified core registers for all processor modes.  In normal
859  * operation this is called on exit from halting debug state.
860  *
861  * @param dpm: represents the processor
862  * @param bpwp: true ensures breakpoints and watchpoints are set,
863  *      false ensures they are cleared
864  */
865 int armv8_dpm_write_dirty_registers(struct arm_dpm *dpm, bool bpwp)
866 {
867         struct arm *arm = dpm->arm;
868         struct reg_cache *cache = arm->core_cache;
869         int retval;
870
871         retval = dpm->prepare(dpm);
872         if (retval != ERROR_OK)
873                 goto done;
874
875         /* If we're managing hardware breakpoints for this core, enable
876          * or disable them as requested.
877          *
878          * REVISIT We don't yet manage them for ANY cores.  Eventually
879          * we should be able to assume we handle them; but until then,
880          * cope with the hand-crafted breakpoint code.
881          */
882         if (arm->target->type->add_breakpoint == dpmv8_add_breakpoint) {
883                 for (unsigned i = 0; i < dpm->nbp; i++) {
884                         struct dpm_bp *dbp = dpm->dbp + i;
885                         struct breakpoint *bp = dbp->bp;
886
887                         retval = dpmv8_maybe_update_bpwp(dpm, bpwp, &dbp->bpwp,
888                                         bp ? &bp->set : NULL);
889                         if (retval != ERROR_OK)
890                                 goto done;
891                 }
892         }
893
894         /* enable/disable watchpoints */
895         for (unsigned i = 0; i < dpm->nwp; i++) {
896                 struct dpm_wp *dwp = dpm->dwp + i;
897                 struct watchpoint *wp = dwp->wp;
898
899                 retval = dpmv8_maybe_update_bpwp(dpm, bpwp, &dwp->bpwp,
900                                 wp ? &wp->set : NULL);
901                 if (retval != ERROR_OK)
902                         goto done;
903         }
904
905         /* NOTE:  writes to breakpoint and watchpoint registers might
906          * be queued, and need (efficient/batched) flushing later.
907          */
908
909         /* Restore original core mode and state */
910         retval = armv8_dpm_modeswitch(dpm, ARM_MODE_ANY);
911         if (retval != ERROR_OK)
912                 goto done;
913
914         /* check everything except our scratch register R0 */
915         for (unsigned i = 1; i < cache->num_regs; i++) {
916                 struct arm_reg *r;
917
918                 /* skip PC and CPSR */
919                 if (i == ARMV8_PC || i == ARMV8_xPSR)
920                         continue;
921                 /* skip invalid */
922                 if (!cache->reg_list[i].valid)
923                         continue;
924                 /* skip non-dirty */
925                 if (!cache->reg_list[i].dirty)
926                         continue;
927
928                 /* skip all registers not on the current EL */
929                 r = cache->reg_list[i].arch_info;
930                 if (r->mode != ARM_MODE_ANY &&
931                                 dpm->last_el != armv8_curel_from_core_mode(r->mode))
932                         continue;
933
934                 retval = dpmv8_write_reg(dpm, &cache->reg_list[i], i);
935                 if (retval != ERROR_OK)
936                         break;
937         }
938
939         /* flush CPSR and PC */
940         if (retval == ERROR_OK)
941                 retval = dpmv8_write_reg(dpm, &cache->reg_list[ARMV8_xPSR], ARMV8_xPSR);
942         if (retval == ERROR_OK)
943                 retval = dpmv8_write_reg(dpm, &cache->reg_list[ARMV8_PC], ARMV8_PC);
944         /* flush R0 -- it's *very* dirty by now */
945         if (retval == ERROR_OK)
946                 retval = dpmv8_write_reg(dpm, &cache->reg_list[0], 0);
947         if (retval == ERROR_OK)
948                 dpm->instr_cpsr_sync(dpm);
949 done:
950         dpm->finish(dpm);
951         return retval;
952 }
953
954 /*
955  * Standard ARM register accessors ... there are three methods
956  * in "struct arm", to support individual read/write and bulk read
957  * of registers.
958  */
959
960 static int armv8_dpm_read_core_reg(struct target *target, struct reg *r,
961         int regnum, enum arm_mode mode)
962 {
963         struct arm *arm = target_to_arm(target);
964         struct arm_dpm *dpm = target_to_arm(target)->dpm;
965         int retval;
966         int max = arm->core_cache->num_regs;
967
968         if (regnum < 0 || regnum >= max)
969                 return ERROR_COMMAND_SYNTAX_ERROR;
970
971         /*
972          * REVISIT what happens if we try to read SPSR in a core mode
973          * which has no such register?
974          */
975         retval = dpm->prepare(dpm);
976         if (retval != ERROR_OK)
977                 return retval;
978
979         retval = dpmv8_read_reg(dpm, r, regnum);
980         if (retval != ERROR_OK)
981                 goto fail;
982
983 fail:
984         /* (void) */ dpm->finish(dpm);
985         return retval;
986 }
987
988 static int armv8_dpm_write_core_reg(struct target *target, struct reg *r,
989         int regnum, enum arm_mode mode, uint8_t *value)
990 {
991         struct arm *arm = target_to_arm(target);
992         struct arm_dpm *dpm = target_to_arm(target)->dpm;
993         int retval;
994         int max = arm->core_cache->num_regs;
995
996         if (regnum < 0 || regnum > max)
997                 return ERROR_COMMAND_SYNTAX_ERROR;
998
999         /* REVISIT what happens if we try to write SPSR in a core mode
1000          * which has no such register?
1001          */
1002
1003         retval = dpm->prepare(dpm);
1004         if (retval != ERROR_OK)
1005                 return retval;
1006
1007         retval = dpmv8_write_reg(dpm, r, regnum);
1008
1009         /* always clean up, regardless of error */
1010         dpm->finish(dpm);
1011
1012         return retval;
1013 }
1014
1015 static int armv8_dpm_full_context(struct target *target)
1016 {
1017         struct arm *arm = target_to_arm(target);
1018         struct arm_dpm *dpm = arm->dpm;
1019         struct reg_cache *cache = arm->core_cache;
1020         int retval;
1021         bool did_read;
1022
1023         retval = dpm->prepare(dpm);
1024         if (retval != ERROR_OK)
1025                 goto done;
1026
1027         do {
1028                 enum arm_mode mode = ARM_MODE_ANY;
1029
1030                 did_read = false;
1031
1032                 /* We "know" arm_dpm_read_current_registers() was called so
1033                  * the unmapped registers (R0..R7, PC, AND CPSR) and some
1034                  * view of R8..R14 are current.  We also "know" oddities of
1035                  * register mapping: special cases for R8..R12 and SPSR.
1036                  *
1037                  * Pick some mode with unread registers and read them all.
1038                  * Repeat until done.
1039                  */
1040                 for (unsigned i = 0; i < cache->num_regs; i++) {
1041                         struct arm_reg *r;
1042
1043                         if (cache->reg_list[i].valid)
1044                                 continue;
1045                         r = cache->reg_list[i].arch_info;
1046
1047                         /* may need to pick a mode and set CPSR */
1048                         if (!did_read) {
1049                                 did_read = true;
1050                                 mode = r->mode;
1051
1052                                 /* For regular (ARM_MODE_ANY) R8..R12
1053                                  * in case we've entered debug state
1054                                  * in FIQ mode we need to patch mode.
1055                                  */
1056                                 if (mode != ARM_MODE_ANY)
1057                                         retval = armv8_dpm_modeswitch(dpm, mode);
1058                                 else
1059                                         retval = armv8_dpm_modeswitch(dpm, ARM_MODE_USR);
1060
1061                                 if (retval != ERROR_OK)
1062                                         goto done;
1063                         }
1064                         if (r->mode != mode)
1065                                 continue;
1066
1067                         /* CPSR was read, so "R16" must mean SPSR */
1068                         retval = dpmv8_read_reg(dpm,
1069                                         &cache->reg_list[i],
1070                                         (r->num == 16) ? 17 : r->num);
1071                         if (retval != ERROR_OK)
1072                                 goto done;
1073                 }
1074
1075         } while (did_read);
1076
1077         retval = armv8_dpm_modeswitch(dpm, ARM_MODE_ANY);
1078         /* (void) */ dpm->finish(dpm);
1079 done:
1080         return retval;
1081 }
1082
1083
1084 /*----------------------------------------------------------------------*/
1085
1086 /*
1087  * Breakpoint and Watchpoint support.
1088  *
1089  * Hardware {break,watch}points are usually left active, to minimize
1090  * debug entry/exit costs.  When they are set or cleared, it's done in
1091  * batches.  Also, DPM-conformant hardware can update debug registers
1092  * regardless of whether the CPU is running or halted ... though that
1093  * fact isn't currently leveraged.
1094  */
1095
1096 static int dpmv8_bpwp_setup(struct arm_dpm *dpm, struct dpm_bpwp *xp,
1097         uint32_t addr, uint32_t length)
1098 {
1099         uint32_t control;
1100
1101         control = (1 << 0)      /* enable */
1102                 | (3 << 1);     /* both user and privileged access */
1103
1104         /* Match 1, 2, or all 4 byte addresses in this word.
1105          *
1106          * FIXME:  v7 hardware allows lengths up to 2 GB for BP and WP.
1107          * Support larger length, when addr is suitably aligned.  In
1108          * particular, allow watchpoints on 8 byte "double" values.
1109          *
1110          * REVISIT allow watchpoints on unaligned 2-bit values; and on
1111          * v7 hardware, unaligned 4-byte ones too.
1112          */
1113         switch (length) {
1114                 case 1:
1115                         control |= (1 << (addr & 3)) << 5;
1116                         break;
1117                 case 2:
1118                         /* require 2-byte alignment */
1119                         if (!(addr & 1)) {
1120                                 control |= (3 << (addr & 2)) << 5;
1121                                 break;
1122                         }
1123                 /* FALL THROUGH */
1124                 case 4:
1125                         /* require 4-byte alignment */
1126                         if (!(addr & 3)) {
1127                                 control |= 0xf << 5;
1128                                 break;
1129                         }
1130                 /* FALL THROUGH */
1131                 default:
1132                         LOG_ERROR("unsupported {break,watch}point length/alignment");
1133                         return ERROR_COMMAND_SYNTAX_ERROR;
1134         }
1135
1136         /* other shared control bits:
1137          * bits 15:14 == 0 ... both secure and nonsecure states (v6.1+ only)
1138          * bit 20 == 0 ... not linked to a context ID
1139          * bit 28:24 == 0 ... not ignoring N LSBs (v7 only)
1140          */
1141
1142         xp->address = addr & ~3;
1143         xp->control = control;
1144         xp->dirty = true;
1145
1146         LOG_DEBUG("BPWP: addr %8.8" PRIx32 ", control %" PRIx32 ", number %d",
1147                 xp->address, control, xp->number);
1148
1149         /* hardware is updated in write_dirty_registers() */
1150         return ERROR_OK;
1151 }
1152
1153 static int dpmv8_add_breakpoint(struct target *target, struct breakpoint *bp)
1154 {
1155         struct arm *arm = target_to_arm(target);
1156         struct arm_dpm *dpm = arm->dpm;
1157         int retval = ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
1158
1159         if (bp->length < 2)
1160                 return ERROR_COMMAND_SYNTAX_ERROR;
1161         if (!dpm->bpwp_enable)
1162                 return retval;
1163
1164         /* FIXME we need a generic solution for software breakpoints. */
1165         if (bp->type == BKPT_SOFT)
1166                 LOG_DEBUG("using HW bkpt, not SW...");
1167
1168         for (unsigned i = 0; i < dpm->nbp; i++) {
1169                 if (!dpm->dbp[i].bp) {
1170                         retval = dpmv8_bpwp_setup(dpm, &dpm->dbp[i].bpwp,
1171                                         bp->address, bp->length);
1172                         if (retval == ERROR_OK)
1173                                 dpm->dbp[i].bp = bp;
1174                         break;
1175                 }
1176         }
1177
1178         return retval;
1179 }
1180
1181 static int dpmv8_remove_breakpoint(struct target *target, struct breakpoint *bp)
1182 {
1183         struct arm *arm = target_to_arm(target);
1184         struct arm_dpm *dpm = arm->dpm;
1185         int retval = ERROR_COMMAND_SYNTAX_ERROR;
1186
1187         for (unsigned i = 0; i < dpm->nbp; i++) {
1188                 if (dpm->dbp[i].bp == bp) {
1189                         dpm->dbp[i].bp = NULL;
1190                         dpm->dbp[i].bpwp.dirty = true;
1191
1192                         /* hardware is updated in write_dirty_registers() */
1193                         retval = ERROR_OK;
1194                         break;
1195                 }
1196         }
1197
1198         return retval;
1199 }
1200
1201 static int dpmv8_watchpoint_setup(struct arm_dpm *dpm, unsigned index_t,
1202         struct watchpoint *wp)
1203 {
1204         int retval;
1205         struct dpm_wp *dwp = dpm->dwp + index_t;
1206         uint32_t control;
1207
1208         /* this hardware doesn't support data value matching or masking */
1209         if (wp->value || wp->mask != ~(uint32_t)0) {
1210                 LOG_DEBUG("watchpoint values and masking not supported");
1211                 return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
1212         }
1213
1214         retval = dpmv8_bpwp_setup(dpm, &dwp->bpwp, wp->address, wp->length);
1215         if (retval != ERROR_OK)
1216                 return retval;
1217
1218         control = dwp->bpwp.control;
1219         switch (wp->rw) {
1220                 case WPT_READ:
1221                         control |= 1 << 3;
1222                         break;
1223                 case WPT_WRITE:
1224                         control |= 2 << 3;
1225                         break;
1226                 case WPT_ACCESS:
1227                         control |= 3 << 3;
1228                         break;
1229         }
1230         dwp->bpwp.control = control;
1231
1232         dpm->dwp[index_t].wp = wp;
1233
1234         return retval;
1235 }
1236
1237 static int dpmv8_add_watchpoint(struct target *target, struct watchpoint *wp)
1238 {
1239         struct arm *arm = target_to_arm(target);
1240         struct arm_dpm *dpm = arm->dpm;
1241         int retval = ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
1242
1243         if (dpm->bpwp_enable) {
1244                 for (unsigned i = 0; i < dpm->nwp; i++) {
1245                         if (!dpm->dwp[i].wp) {
1246                                 retval = dpmv8_watchpoint_setup(dpm, i, wp);
1247                                 break;
1248                         }
1249                 }
1250         }
1251
1252         return retval;
1253 }
1254
1255 static int dpmv8_remove_watchpoint(struct target *target, struct watchpoint *wp)
1256 {
1257         struct arm *arm = target_to_arm(target);
1258         struct arm_dpm *dpm = arm->dpm;
1259         int retval = ERROR_COMMAND_SYNTAX_ERROR;
1260
1261         for (unsigned i = 0; i < dpm->nwp; i++) {
1262                 if (dpm->dwp[i].wp == wp) {
1263                         dpm->dwp[i].wp = NULL;
1264                         dpm->dwp[i].bpwp.dirty = true;
1265
1266                         /* hardware is updated in write_dirty_registers() */
1267                         retval = ERROR_OK;
1268                         break;
1269                 }
1270         }
1271
1272         return retval;
1273 }
1274
1275 void armv8_dpm_report_wfar(struct arm_dpm *dpm, uint64_t addr)
1276 {
1277         switch (dpm->arm->core_state) {
1278                 case ARM_STATE_ARM:
1279                 case ARM_STATE_AARCH64:
1280                         addr -= 8;
1281                         break;
1282                 case ARM_STATE_THUMB:
1283                 case ARM_STATE_THUMB_EE:
1284                         addr -= 4;
1285                         break;
1286                 case ARM_STATE_JAZELLE:
1287                         /* ?? */
1288                         break;
1289                 default:
1290                         LOG_DEBUG("Unknown core_state");
1291                         break;
1292         }
1293         dpm->wp_pc = addr;
1294 }
1295
1296 /*
1297  * Handle exceptions taken in debug state. This happens mostly for memory
1298  * accesses that violated a MMU policy. Taking an exception while in debug
1299  * state clobbers certain state registers on the target exception level.
1300  * Just mark those registers dirty so that they get restored on resume.
1301  * This works both for Aarch32 and Aarch64 states.
1302  *
1303  * This function must not perform any actions that trigger another exception
1304  * or a recursion will happen.
1305  */
1306 void armv8_dpm_handle_exception(struct arm_dpm *dpm, bool do_restore)
1307 {
1308         struct armv8_common *armv8 = dpm->arm->arch_info;
1309         struct reg_cache *cache = dpm->arm->core_cache;
1310         enum arm_state core_state;
1311         uint64_t dlr;
1312         uint32_t dspsr;
1313         unsigned int el;
1314
1315         static const int clobbered_regs_by_el[3][5] = {
1316                 { ARMV8_PC, ARMV8_xPSR, ARMV8_ELR_EL1, ARMV8_ESR_EL1, ARMV8_SPSR_EL1 },
1317                 { ARMV8_PC, ARMV8_xPSR, ARMV8_ELR_EL2, ARMV8_ESR_EL2, ARMV8_SPSR_EL2 },
1318                 { ARMV8_PC, ARMV8_xPSR, ARMV8_ELR_EL3, ARMV8_ESR_EL3, ARMV8_SPSR_EL3 },
1319         };
1320
1321         el = (dpm->dscr >> 8) & 3;
1322
1323         /* safety check, must not happen since EL0 cannot be a target for an exception */
1324         if (el < SYSTEM_CUREL_EL1 || el > SYSTEM_CUREL_EL3) {
1325                 LOG_ERROR("%s: EL %i is invalid, DSCR corrupted?", __func__, el);
1326                 return;
1327         }
1328
1329         /* Clear sticky error */
1330         mem_ap_write_u32(armv8->debug_ap,
1331                 armv8->debug_base + CPUV8_DBG_DRCR, DRCR_CSE);
1332
1333         armv8->read_reg_u64(armv8, ARMV8_xPSR, &dlr);
1334         dspsr = dlr;
1335         armv8->read_reg_u64(armv8, ARMV8_PC, &dlr);
1336
1337         LOG_DEBUG("Exception taken to EL %i, DLR=0x%016"PRIx64" DSPSR=0x%08"PRIx32,
1338                         el, dlr, dspsr);
1339
1340         /* mark all clobbered registers as dirty */
1341         for (int i = 0; i < 5; i++)
1342                 cache->reg_list[clobbered_regs_by_el[el-1][i]].dirty = true;
1343
1344         /*
1345          * re-evaluate the core state, we might be in Aarch64 state now
1346          * we rely on dpm->dscr being up-to-date
1347          */
1348         core_state = armv8_dpm_get_core_state(dpm);
1349         armv8_select_opcodes(armv8, core_state == ARM_STATE_AARCH64);
1350         armv8_select_reg_access(armv8, core_state == ARM_STATE_AARCH64);
1351
1352         if (do_restore)
1353                 armv8_dpm_modeswitch(dpm, ARM_MODE_ANY);
1354 }
1355
1356 /*----------------------------------------------------------------------*/
1357
1358 /*
1359  * Other debug and support utilities
1360  */
1361
1362 void armv8_dpm_report_dscr(struct arm_dpm *dpm, uint32_t dscr)
1363 {
1364         struct target *target = dpm->arm->target;
1365
1366         dpm->dscr = dscr;
1367         dpm->last_el = (dscr >> 8) & 3;
1368
1369         /* Examine debug reason */
1370         switch (DSCR_ENTRY(dscr)) {
1371                 /* FALL THROUGH -- assume a v6 core in abort mode */
1372                 case DSCRV8_ENTRY_EXT_DEBUG:    /* EDBGRQ */
1373                         target->debug_reason = DBG_REASON_DBGRQ;
1374                         break;
1375                 case DSCRV8_ENTRY_HALT_STEP_EXECLU:     /* HALT step */
1376                 case DSCRV8_ENTRY_HALT_STEP_NORMAL: /* Halt step*/
1377                 case DSCRV8_ENTRY_HALT_STEP:
1378                         target->debug_reason = DBG_REASON_SINGLESTEP;
1379                         break;
1380                 case DSCRV8_ENTRY_HLT:  /* HLT instruction (software breakpoint) */
1381                 case DSCRV8_ENTRY_BKPT: /* SW BKPT (?) */
1382                 case DSCRV8_ENTRY_RESET_CATCH:  /* Reset catch */
1383                 case DSCRV8_ENTRY_OS_UNLOCK:  /*OS unlock catch*/
1384                 case DSCRV8_ENTRY_EXCEPTION_CATCH:  /*exception catch*/
1385                 case DSCRV8_ENTRY_SW_ACCESS_DBG: /*SW access dbg register*/
1386                         target->debug_reason = DBG_REASON_BREAKPOINT;
1387                         break;
1388                 case DSCRV8_ENTRY_WATCHPOINT:   /* asynch watchpoint */
1389                         target->debug_reason = DBG_REASON_WATCHPOINT;
1390                         break;
1391                 default:
1392                         target->debug_reason = DBG_REASON_UNDEFINED;
1393                         break;
1394         }
1395
1396 }
1397
1398 /*----------------------------------------------------------------------*/
1399
1400 /*
1401  * Setup and management support.
1402  */
1403
1404 /**
1405  * Hooks up this DPM to its associated target; call only once.
1406  * Initially this only covers the register cache.
1407  *
1408  * Oh, and watchpoints.  Yeah.
1409  */
1410 int armv8_dpm_setup(struct arm_dpm *dpm)
1411 {
1412         struct arm *arm = dpm->arm;
1413         struct target *target = arm->target;
1414         struct reg_cache *cache;
1415         arm->dpm = dpm;
1416
1417         /* register access setup */
1418         arm->full_context = armv8_dpm_full_context;
1419         arm->read_core_reg = armv8_dpm_read_core_reg;
1420         arm->write_core_reg = armv8_dpm_write_core_reg;
1421
1422         if (arm->core_cache == NULL) {
1423                 cache = armv8_build_reg_cache(target);
1424                 if (!cache)
1425                         return ERROR_FAIL;
1426         }
1427
1428         /* coprocessor access setup */
1429         arm->mrc = dpmv8_mrc;
1430         arm->mcr = dpmv8_mcr;
1431
1432         dpm->prepare = dpmv8_dpm_prepare;
1433         dpm->finish = dpmv8_dpm_finish;
1434
1435         dpm->instr_execute = dpmv8_instr_execute;
1436         dpm->instr_write_data_dcc = dpmv8_instr_write_data_dcc;
1437         dpm->instr_write_data_dcc_64 = dpmv8_instr_write_data_dcc_64;
1438         dpm->instr_write_data_r0 = dpmv8_instr_write_data_r0;
1439         dpm->instr_write_data_r0_64 = dpmv8_instr_write_data_r0_64;
1440         dpm->instr_cpsr_sync = dpmv8_instr_cpsr_sync;
1441
1442         dpm->instr_read_data_dcc = dpmv8_instr_read_data_dcc;
1443         dpm->instr_read_data_dcc_64 = dpmv8_instr_read_data_dcc_64;
1444         dpm->instr_read_data_r0 = dpmv8_instr_read_data_r0;
1445         dpm->instr_read_data_r0_64 = dpmv8_instr_read_data_r0_64;
1446
1447         dpm->arm_reg_current = armv8_reg_current;
1448
1449 /*      dpm->bpwp_enable = dpmv8_bpwp_enable; */
1450         dpm->bpwp_disable = dpmv8_bpwp_disable;
1451
1452         /* breakpoint setup -- optional until it works everywhere */
1453         if (!target->type->add_breakpoint) {
1454                 target->type->add_breakpoint = dpmv8_add_breakpoint;
1455                 target->type->remove_breakpoint = dpmv8_remove_breakpoint;
1456         }
1457
1458         /* watchpoint setup */
1459         target->type->add_watchpoint = dpmv8_add_watchpoint;
1460         target->type->remove_watchpoint = dpmv8_remove_watchpoint;
1461
1462         /* FIXME add vector catch support */
1463
1464         dpm->nbp = 1 + ((dpm->didr >> 12) & 0xf);
1465         dpm->dbp = calloc(dpm->nbp, sizeof *dpm->dbp);
1466
1467         dpm->nwp = 1 + ((dpm->didr >> 20) & 0xf);
1468         dpm->dwp = calloc(dpm->nwp, sizeof *dpm->dwp);
1469
1470         if (!dpm->dbp || !dpm->dwp) {
1471                 free(dpm->dbp);
1472                 free(dpm->dwp);
1473                 return ERROR_FAIL;
1474         }
1475
1476         LOG_INFO("%s: hardware has %d breakpoints, %d watchpoints",
1477                 target_name(target), dpm->nbp, dpm->nwp);
1478
1479         /* REVISIT ... and some of those breakpoints could match
1480          * execution context IDs...
1481          */
1482
1483         return ERROR_OK;
1484 }
1485
1486 /**
1487  * Reinitializes DPM state at the beginning of a new debug session
1488  * or after a reset which may have affected the debug module.
1489  */
1490 int armv8_dpm_initialize(struct arm_dpm *dpm)
1491 {
1492         /* Disable all breakpoints and watchpoints at startup. */
1493         if (dpm->bpwp_disable) {
1494                 unsigned i;
1495
1496                 for (i = 0; i < dpm->nbp; i++) {
1497                         dpm->dbp[i].bpwp.number = i;
1498                         (void) dpm->bpwp_disable(dpm, i);
1499                 }
1500                 for (i = 0; i < dpm->nwp; i++) {
1501                         dpm->dwp[i].bpwp.number = 16 + i;
1502                         (void) dpm->bpwp_disable(dpm, 16 + i);
1503                 }
1504         } else
1505                 LOG_WARNING("%s: can't disable breakpoints and watchpoints",
1506                         target_name(dpm->arm->target));
1507
1508         return ERROR_OK;
1509 }