xref: /openbmc/qemu/target/riscv/debug.c (revision 8cbb4fc1)
1 /*
2  * QEMU RISC-V Native Debug Support
3  *
4  * Copyright (c) 2022 Wind River Systems, Inc.
5  *
6  * Author:
7  *   Bin Meng <bin.meng@windriver.com>
8  *
9  * This provides the native debug support via the Trigger Module, as defined
10  * in the RISC-V Debug Specification:
11  * https://github.com/riscv/riscv-debug-spec/raw/master/riscv-debug-stable.pdf
12  *
13  * This program is free software; you can redistribute it and/or modify it
14  * under the terms and conditions of the GNU General Public License,
15  * version 2 or later, as published by the Free Software Foundation.
16  *
17  * This program is distributed in the hope it will be useful, but WITHOUT
18  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
19  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
20  * more details.
21  *
22  * You should have received a copy of the GNU General Public License along with
23  * this program.  If not, see <http://www.gnu.org/licenses/>.
24  */
25 
26 #include "qemu/osdep.h"
27 #include "qemu/log.h"
28 #include "qapi/error.h"
29 #include "cpu.h"
30 #include "trace.h"
31 #include "exec/exec-all.h"
32 #include "exec/helper-proto.h"
33 #include "sysemu/cpu-timers.h"
34 
35 /*
36  * The following M-mode trigger CSRs are implemented:
37  *
38  * - tselect
39  * - tdata1
40  * - tdata2
41  * - tdata3
42  * - tinfo
43  *
44  * The following triggers are initialized by default:
45  *
46  * Index | Type |          tdata mapping | Description
47  * ------+------+------------------------+------------
48  *     0 |    2 |         tdata1, tdata2 | Address / Data Match
49  *     1 |    2 |         tdata1, tdata2 | Address / Data Match
50  */
51 
52 /* tdata availability of a trigger */
53 typedef bool tdata_avail[TDATA_NUM];
54 
55 static tdata_avail tdata_mapping[TRIGGER_TYPE_NUM] = {
56     [TRIGGER_TYPE_NO_EXIST] = { false, false, false },
57     [TRIGGER_TYPE_AD_MATCH] = { true, true, true },
58     [TRIGGER_TYPE_INST_CNT] = { true, false, true },
59     [TRIGGER_TYPE_INT] = { true, true, true },
60     [TRIGGER_TYPE_EXCP] = { true, true, true },
61     [TRIGGER_TYPE_AD_MATCH6] = { true, true, true },
62     [TRIGGER_TYPE_EXT_SRC] = { true, false, false },
63     [TRIGGER_TYPE_UNAVAIL] = { true, true, true }
64 };
65 
66 /* only breakpoint size 1/2/4/8 supported */
67 static int access_size[SIZE_NUM] = {
68     [SIZE_ANY] = 0,
69     [SIZE_1B]  = 1,
70     [SIZE_2B]  = 2,
71     [SIZE_4B]  = 4,
72     [SIZE_6B]  = -1,
73     [SIZE_8B]  = 8,
74     [6 ... 15] = -1,
75 };
76 
77 static inline target_ulong extract_trigger_type(CPURISCVState *env,
78                                                 target_ulong tdata1)
79 {
80     switch (riscv_cpu_mxl(env)) {
81     case MXL_RV32:
82         return extract32(tdata1, 28, 4);
83     case MXL_RV64:
84     case MXL_RV128:
85         return extract64(tdata1, 60, 4);
86     default:
87         g_assert_not_reached();
88     }
89 }
90 
91 static inline target_ulong get_trigger_type(CPURISCVState *env,
92                                             target_ulong trigger_index)
93 {
94     return extract_trigger_type(env, env->tdata1[trigger_index]);
95 }
96 
97 static trigger_action_t get_trigger_action(CPURISCVState *env,
98                                            target_ulong trigger_index)
99 {
100     target_ulong tdata1 = env->tdata1[trigger_index];
101     int trigger_type = get_trigger_type(env, trigger_index);
102     trigger_action_t action = DBG_ACTION_NONE;
103 
104     switch (trigger_type) {
105     case TRIGGER_TYPE_AD_MATCH:
106         action = (tdata1 & TYPE2_ACTION) >> 12;
107         break;
108     case TRIGGER_TYPE_AD_MATCH6:
109         action = (tdata1 & TYPE6_ACTION) >> 12;
110         break;
111     case TRIGGER_TYPE_INST_CNT:
112     case TRIGGER_TYPE_INT:
113     case TRIGGER_TYPE_EXCP:
114     case TRIGGER_TYPE_EXT_SRC:
115         qemu_log_mask(LOG_UNIMP, "trigger type: %d is not supported\n",
116                       trigger_type);
117         break;
118     case TRIGGER_TYPE_NO_EXIST:
119     case TRIGGER_TYPE_UNAVAIL:
120         qemu_log_mask(LOG_GUEST_ERROR, "trigger type: %d does not exit\n",
121                       trigger_type);
122         break;
123     default:
124         g_assert_not_reached();
125     }
126 
127     return action;
128 }
129 
130 static inline target_ulong build_tdata1(CPURISCVState *env,
131                                         trigger_type_t type,
132                                         bool dmode, target_ulong data)
133 {
134     target_ulong tdata1;
135 
136     switch (riscv_cpu_mxl(env)) {
137     case MXL_RV32:
138         tdata1 = RV32_TYPE(type) |
139                  (dmode ? RV32_DMODE : 0) |
140                  (data & RV32_DATA_MASK);
141         break;
142     case MXL_RV64:
143     case MXL_RV128:
144         tdata1 = RV64_TYPE(type) |
145                  (dmode ? RV64_DMODE : 0) |
146                  (data & RV64_DATA_MASK);
147         break;
148     default:
149         g_assert_not_reached();
150     }
151 
152     return tdata1;
153 }
154 
155 bool tdata_available(CPURISCVState *env, int tdata_index)
156 {
157     int trigger_type = get_trigger_type(env, env->trigger_cur);
158 
159     if (unlikely(tdata_index >= TDATA_NUM)) {
160         return false;
161     }
162 
163     return tdata_mapping[trigger_type][tdata_index];
164 }
165 
166 target_ulong tselect_csr_read(CPURISCVState *env)
167 {
168     return env->trigger_cur;
169 }
170 
171 void tselect_csr_write(CPURISCVState *env, target_ulong val)
172 {
173     if (val < RV_MAX_TRIGGERS) {
174         env->trigger_cur = val;
175     }
176 }
177 
178 static target_ulong tdata1_validate(CPURISCVState *env, target_ulong val,
179                                     trigger_type_t t)
180 {
181     uint32_t type, dmode;
182     target_ulong tdata1;
183 
184     switch (riscv_cpu_mxl(env)) {
185     case MXL_RV32:
186         type = extract32(val, 28, 4);
187         dmode = extract32(val, 27, 1);
188         tdata1 = RV32_TYPE(t);
189         break;
190     case MXL_RV64:
191     case MXL_RV128:
192         type = extract64(val, 60, 4);
193         dmode = extract64(val, 59, 1);
194         tdata1 = RV64_TYPE(t);
195         break;
196     default:
197         g_assert_not_reached();
198     }
199 
200     if (type != t) {
201         qemu_log_mask(LOG_GUEST_ERROR,
202                       "ignoring type write to tdata1 register\n");
203     }
204 
205     if (dmode != 0) {
206         qemu_log_mask(LOG_UNIMP, "debug mode is not supported\n");
207     }
208 
209     return tdata1;
210 }
211 
212 static inline void warn_always_zero_bit(target_ulong val, target_ulong mask,
213                                         const char *msg)
214 {
215     if (val & mask) {
216         qemu_log_mask(LOG_UNIMP, "%s bit is always zero\n", msg);
217     }
218 }
219 
220 static void do_trigger_action(CPURISCVState *env, target_ulong trigger_index)
221 {
222     trigger_action_t action = get_trigger_action(env, trigger_index);
223 
224     switch (action) {
225     case DBG_ACTION_NONE:
226         break;
227     case DBG_ACTION_BP:
228         riscv_raise_exception(env, RISCV_EXCP_BREAKPOINT, 0);
229         break;
230     case DBG_ACTION_DBG_MODE:
231     case DBG_ACTION_TRACE0:
232     case DBG_ACTION_TRACE1:
233     case DBG_ACTION_TRACE2:
234     case DBG_ACTION_TRACE3:
235     case DBG_ACTION_EXT_DBG0:
236     case DBG_ACTION_EXT_DBG1:
237         qemu_log_mask(LOG_UNIMP, "action: %d is not supported\n", action);
238         break;
239     default:
240         g_assert_not_reached();
241     }
242 }
243 
244 /*
245  * Check the privilege level of specific trigger matches CPU's current privilege
246  * level.
247  */
248 static bool trigger_priv_match(CPURISCVState *env, trigger_type_t type,
249                                int trigger_index)
250 {
251     target_ulong ctrl = env->tdata1[trigger_index];
252 
253     switch (type) {
254     case TRIGGER_TYPE_AD_MATCH:
255         /* type 2 trigger cannot be fired in VU/VS mode */
256         if (env->virt_enabled) {
257             return false;
258         }
259         /* check U/S/M bit against current privilege level */
260         if ((ctrl >> 3) & BIT(env->priv)) {
261             return true;
262         }
263         break;
264     case TRIGGER_TYPE_AD_MATCH6:
265         if (env->virt_enabled) {
266             /* check VU/VS bit against current privilege level */
267             if ((ctrl >> 23) & BIT(env->priv)) {
268                 return true;
269             }
270         } else {
271             /* check U/S/M bit against current privilege level */
272             if ((ctrl >> 3) & BIT(env->priv)) {
273                 return true;
274             }
275         }
276         break;
277     case TRIGGER_TYPE_INST_CNT:
278         if (env->virt_enabled) {
279             /* check VU/VS bit against current privilege level */
280             if ((ctrl >> 25) & BIT(env->priv)) {
281                 return true;
282             }
283         } else {
284             /* check U/S/M bit against current privilege level */
285             if ((ctrl >> 6) & BIT(env->priv)) {
286                 return true;
287             }
288         }
289         break;
290     case TRIGGER_TYPE_INT:
291     case TRIGGER_TYPE_EXCP:
292     case TRIGGER_TYPE_EXT_SRC:
293         qemu_log_mask(LOG_UNIMP, "trigger type: %d is not supported\n", type);
294         break;
295     case TRIGGER_TYPE_NO_EXIST:
296     case TRIGGER_TYPE_UNAVAIL:
297         qemu_log_mask(LOG_GUEST_ERROR, "trigger type: %d does not exist\n",
298                       type);
299         break;
300     default:
301         g_assert_not_reached();
302     }
303 
304     return false;
305 }
306 
307 /* Common matching conditions for all types of the triggers. */
308 static bool trigger_common_match(CPURISCVState *env, trigger_type_t type,
309                                  int trigger_index)
310 {
311     return trigger_priv_match(env, type, trigger_index);
312 }
313 
314 /* type 2 trigger */
315 
316 static uint32_t type2_breakpoint_size(CPURISCVState *env, target_ulong ctrl)
317 {
318     uint32_t sizelo, sizehi = 0;
319 
320     if (riscv_cpu_mxl(env) == MXL_RV64) {
321         sizehi = extract32(ctrl, 21, 2);
322     }
323     sizelo = extract32(ctrl, 16, 2);
324     return (sizehi << 2) | sizelo;
325 }
326 
327 static inline bool type2_breakpoint_enabled(target_ulong ctrl)
328 {
329     bool mode = !!(ctrl & (TYPE2_U | TYPE2_S | TYPE2_M));
330     bool rwx = !!(ctrl & (TYPE2_LOAD | TYPE2_STORE | TYPE2_EXEC));
331 
332     return mode && rwx;
333 }
334 
335 static target_ulong type2_mcontrol_validate(CPURISCVState *env,
336                                             target_ulong ctrl)
337 {
338     target_ulong val;
339     uint32_t size;
340 
341     /* validate the generic part first */
342     val = tdata1_validate(env, ctrl, TRIGGER_TYPE_AD_MATCH);
343 
344     /* validate unimplemented (always zero) bits */
345     warn_always_zero_bit(ctrl, TYPE2_MATCH, "match");
346     warn_always_zero_bit(ctrl, TYPE2_CHAIN, "chain");
347     warn_always_zero_bit(ctrl, TYPE2_ACTION, "action");
348     warn_always_zero_bit(ctrl, TYPE2_TIMING, "timing");
349     warn_always_zero_bit(ctrl, TYPE2_SELECT, "select");
350     warn_always_zero_bit(ctrl, TYPE2_HIT, "hit");
351 
352     /* validate size encoding */
353     size = type2_breakpoint_size(env, ctrl);
354     if (access_size[size] == -1) {
355         qemu_log_mask(LOG_UNIMP, "access size %d is not supported, using "
356                                  "SIZE_ANY\n", size);
357     } else {
358         val |= (ctrl & TYPE2_SIZELO);
359         if (riscv_cpu_mxl(env) == MXL_RV64) {
360             val |= (ctrl & TYPE2_SIZEHI);
361         }
362     }
363 
364     /* keep the mode and attribute bits */
365     val |= (ctrl & (TYPE2_U | TYPE2_S | TYPE2_M |
366                     TYPE2_LOAD | TYPE2_STORE | TYPE2_EXEC));
367 
368     return val;
369 }
370 
371 static void type2_breakpoint_insert(CPURISCVState *env, target_ulong index)
372 {
373     target_ulong ctrl = env->tdata1[index];
374     target_ulong addr = env->tdata2[index];
375     bool enabled = type2_breakpoint_enabled(ctrl);
376     CPUState *cs = env_cpu(env);
377     int flags = BP_CPU | BP_STOP_BEFORE_ACCESS;
378     uint32_t size;
379 
380     if (!enabled) {
381         return;
382     }
383 
384     if (ctrl & TYPE2_EXEC) {
385         cpu_breakpoint_insert(cs, addr, flags, &env->cpu_breakpoint[index]);
386     }
387 
388     if (ctrl & TYPE2_LOAD) {
389         flags |= BP_MEM_READ;
390     }
391     if (ctrl & TYPE2_STORE) {
392         flags |= BP_MEM_WRITE;
393     }
394 
395     if (flags & BP_MEM_ACCESS) {
396         size = type2_breakpoint_size(env, ctrl);
397         if (size != 0) {
398             cpu_watchpoint_insert(cs, addr, size, flags,
399                                   &env->cpu_watchpoint[index]);
400         } else {
401             cpu_watchpoint_insert(cs, addr, 8, flags,
402                                   &env->cpu_watchpoint[index]);
403         }
404     }
405 }
406 
407 static void type2_breakpoint_remove(CPURISCVState *env, target_ulong index)
408 {
409     CPUState *cs = env_cpu(env);
410 
411     if (env->cpu_breakpoint[index]) {
412         cpu_breakpoint_remove_by_ref(cs, env->cpu_breakpoint[index]);
413         env->cpu_breakpoint[index] = NULL;
414     }
415 
416     if (env->cpu_watchpoint[index]) {
417         cpu_watchpoint_remove_by_ref(cs, env->cpu_watchpoint[index]);
418         env->cpu_watchpoint[index] = NULL;
419     }
420 }
421 
422 static void type2_reg_write(CPURISCVState *env, target_ulong index,
423                             int tdata_index, target_ulong val)
424 {
425     target_ulong new_val;
426 
427     switch (tdata_index) {
428     case TDATA1:
429         new_val = type2_mcontrol_validate(env, val);
430         if (new_val != env->tdata1[index]) {
431             env->tdata1[index] = new_val;
432             type2_breakpoint_remove(env, index);
433             type2_breakpoint_insert(env, index);
434         }
435         break;
436     case TDATA2:
437         if (val != env->tdata2[index]) {
438             env->tdata2[index] = val;
439             type2_breakpoint_remove(env, index);
440             type2_breakpoint_insert(env, index);
441         }
442         break;
443     case TDATA3:
444         qemu_log_mask(LOG_UNIMP,
445                       "tdata3 is not supported for type 2 trigger\n");
446         break;
447     default:
448         g_assert_not_reached();
449     }
450 
451     return;
452 }
453 
454 /* type 6 trigger */
455 
456 static inline bool type6_breakpoint_enabled(target_ulong ctrl)
457 {
458     bool mode = !!(ctrl & (TYPE6_VU | TYPE6_VS | TYPE6_U | TYPE6_S | TYPE6_M));
459     bool rwx = !!(ctrl & (TYPE6_LOAD | TYPE6_STORE | TYPE6_EXEC));
460 
461     return mode && rwx;
462 }
463 
464 static target_ulong type6_mcontrol6_validate(CPURISCVState *env,
465                                              target_ulong ctrl)
466 {
467     target_ulong val;
468     uint32_t size;
469 
470     /* validate the generic part first */
471     val = tdata1_validate(env, ctrl, TRIGGER_TYPE_AD_MATCH6);
472 
473     /* validate unimplemented (always zero) bits */
474     warn_always_zero_bit(ctrl, TYPE6_MATCH, "match");
475     warn_always_zero_bit(ctrl, TYPE6_CHAIN, "chain");
476     warn_always_zero_bit(ctrl, TYPE6_ACTION, "action");
477     warn_always_zero_bit(ctrl, TYPE6_TIMING, "timing");
478     warn_always_zero_bit(ctrl, TYPE6_SELECT, "select");
479     warn_always_zero_bit(ctrl, TYPE6_HIT, "hit");
480 
481     /* validate size encoding */
482     size = extract32(ctrl, 16, 4);
483     if (access_size[size] == -1) {
484         qemu_log_mask(LOG_UNIMP, "access size %d is not supported, using "
485                                  "SIZE_ANY\n", size);
486     } else {
487         val |= (ctrl & TYPE6_SIZE);
488     }
489 
490     /* keep the mode and attribute bits */
491     val |= (ctrl & (TYPE6_VU | TYPE6_VS | TYPE6_U | TYPE6_S | TYPE6_M |
492                     TYPE6_LOAD | TYPE6_STORE | TYPE6_EXEC));
493 
494     return val;
495 }
496 
497 static void type6_breakpoint_insert(CPURISCVState *env, target_ulong index)
498 {
499     target_ulong ctrl = env->tdata1[index];
500     target_ulong addr = env->tdata2[index];
501     bool enabled = type6_breakpoint_enabled(ctrl);
502     CPUState *cs = env_cpu(env);
503     int flags = BP_CPU | BP_STOP_BEFORE_ACCESS;
504     uint32_t size;
505 
506     if (!enabled) {
507         return;
508     }
509 
510     if (ctrl & TYPE6_EXEC) {
511         cpu_breakpoint_insert(cs, addr, flags, &env->cpu_breakpoint[index]);
512     }
513 
514     if (ctrl & TYPE6_LOAD) {
515         flags |= BP_MEM_READ;
516     }
517 
518     if (ctrl & TYPE6_STORE) {
519         flags |= BP_MEM_WRITE;
520     }
521 
522     if (flags & BP_MEM_ACCESS) {
523         size = extract32(ctrl, 16, 4);
524         if (size != 0) {
525             cpu_watchpoint_insert(cs, addr, size, flags,
526                                   &env->cpu_watchpoint[index]);
527         } else {
528             cpu_watchpoint_insert(cs, addr, 8, flags,
529                                   &env->cpu_watchpoint[index]);
530         }
531     }
532 }
533 
534 static void type6_breakpoint_remove(CPURISCVState *env, target_ulong index)
535 {
536     type2_breakpoint_remove(env, index);
537 }
538 
539 static void type6_reg_write(CPURISCVState *env, target_ulong index,
540                             int tdata_index, target_ulong val)
541 {
542     target_ulong new_val;
543 
544     switch (tdata_index) {
545     case TDATA1:
546         new_val = type6_mcontrol6_validate(env, val);
547         if (new_val != env->tdata1[index]) {
548             env->tdata1[index] = new_val;
549             type6_breakpoint_remove(env, index);
550             type6_breakpoint_insert(env, index);
551         }
552         break;
553     case TDATA2:
554         if (val != env->tdata2[index]) {
555             env->tdata2[index] = val;
556             type6_breakpoint_remove(env, index);
557             type6_breakpoint_insert(env, index);
558         }
559         break;
560     case TDATA3:
561         qemu_log_mask(LOG_UNIMP,
562                       "tdata3 is not supported for type 6 trigger\n");
563         break;
564     default:
565         g_assert_not_reached();
566     }
567 
568     return;
569 }
570 
571 /* icount trigger type */
572 static inline int
573 itrigger_get_count(CPURISCVState *env, int index)
574 {
575     return get_field(env->tdata1[index], ITRIGGER_COUNT);
576 }
577 
578 static inline void
579 itrigger_set_count(CPURISCVState *env, int index, int value)
580 {
581     env->tdata1[index] = set_field(env->tdata1[index],
582                                    ITRIGGER_COUNT, value);
583 }
584 
585 static bool check_itrigger_priv(CPURISCVState *env, int index)
586 {
587     target_ulong tdata1 = env->tdata1[index];
588     if (env->virt_enabled) {
589         /* check VU/VS bit against current privilege level */
590         return (get_field(tdata1, ITRIGGER_VS) == env->priv) ||
591                (get_field(tdata1, ITRIGGER_VU) == env->priv);
592     } else {
593         /* check U/S/M bit against current privilege level */
594         return (get_field(tdata1, ITRIGGER_M) == env->priv) ||
595                (get_field(tdata1, ITRIGGER_S) == env->priv) ||
596                (get_field(tdata1, ITRIGGER_U) == env->priv);
597     }
598 }
599 
600 bool riscv_itrigger_enabled(CPURISCVState *env)
601 {
602     int count;
603     for (int i = 0; i < RV_MAX_TRIGGERS; i++) {
604         if (get_trigger_type(env, i) != TRIGGER_TYPE_INST_CNT) {
605             continue;
606         }
607         if (check_itrigger_priv(env, i)) {
608             continue;
609         }
610         count = itrigger_get_count(env, i);
611         if (!count) {
612             continue;
613         }
614         return true;
615     }
616 
617     return false;
618 }
619 
620 void helper_itrigger_match(CPURISCVState *env)
621 {
622     int count;
623     for (int i = 0; i < RV_MAX_TRIGGERS; i++) {
624         if (get_trigger_type(env, i) != TRIGGER_TYPE_INST_CNT) {
625             continue;
626         }
627         if (!trigger_common_match(env, TRIGGER_TYPE_INST_CNT, i)) {
628             continue;
629         }
630         count = itrigger_get_count(env, i);
631         if (!count) {
632             continue;
633         }
634         itrigger_set_count(env, i, count--);
635         if (!count) {
636             env->itrigger_enabled = riscv_itrigger_enabled(env);
637             do_trigger_action(env, i);
638         }
639     }
640 }
641 
642 static void riscv_itrigger_update_count(CPURISCVState *env)
643 {
644     int count, executed;
645     /*
646      * Record last icount, so that we can evaluate the executed instructions
647      * since last privilege mode change or timer expire.
648      */
649     int64_t last_icount = env->last_icount, current_icount;
650     current_icount = env->last_icount = icount_get_raw();
651 
652     for (int i = 0; i < RV_MAX_TRIGGERS; i++) {
653         if (get_trigger_type(env, i) != TRIGGER_TYPE_INST_CNT) {
654             continue;
655         }
656         count = itrigger_get_count(env, i);
657         if (!count) {
658             continue;
659         }
660         /*
661          * Only when privilege is changed or itrigger timer expires,
662          * the count field in itrigger tdata1 register is updated.
663          * And the count field in itrigger only contains remaining value.
664          */
665         if (check_itrigger_priv(env, i)) {
666             /*
667              * If itrigger enabled in this privilege mode, the number of
668              * executed instructions since last privilege change
669              * should be reduced from current itrigger count.
670              */
671             executed = current_icount - last_icount;
672             itrigger_set_count(env, i, count - executed);
673             if (count == executed) {
674                 do_trigger_action(env, i);
675             }
676         } else {
677             /*
678              * If itrigger is not enabled in this privilege mode,
679              * the number of executed instructions will be discard and
680              * the count field in itrigger will not change.
681              */
682             timer_mod(env->itrigger_timer[i],
683                       current_icount + count);
684         }
685     }
686 }
687 
688 static void riscv_itrigger_timer_cb(void *opaque)
689 {
690     riscv_itrigger_update_count((CPURISCVState *)opaque);
691 }
692 
693 void riscv_itrigger_update_priv(CPURISCVState *env)
694 {
695     riscv_itrigger_update_count(env);
696 }
697 
698 static target_ulong itrigger_validate(CPURISCVState *env,
699                                       target_ulong ctrl)
700 {
701     target_ulong val;
702 
703     /* validate the generic part first */
704     val = tdata1_validate(env, ctrl, TRIGGER_TYPE_INST_CNT);
705 
706     /* validate unimplemented (always zero) bits */
707     warn_always_zero_bit(ctrl, ITRIGGER_ACTION, "action");
708     warn_always_zero_bit(ctrl, ITRIGGER_HIT, "hit");
709     warn_always_zero_bit(ctrl, ITRIGGER_PENDING, "pending");
710 
711     /* keep the mode and attribute bits */
712     val |= ctrl & (ITRIGGER_VU | ITRIGGER_VS | ITRIGGER_U | ITRIGGER_S |
713                    ITRIGGER_M | ITRIGGER_COUNT);
714 
715     return val;
716 }
717 
718 static void itrigger_reg_write(CPURISCVState *env, target_ulong index,
719                                int tdata_index, target_ulong val)
720 {
721     target_ulong new_val;
722 
723     switch (tdata_index) {
724     case TDATA1:
725         /* set timer for icount */
726         new_val = itrigger_validate(env, val);
727         if (new_val != env->tdata1[index]) {
728             env->tdata1[index] = new_val;
729             if (icount_enabled()) {
730                 env->last_icount = icount_get_raw();
731                 /* set the count to timer */
732                 timer_mod(env->itrigger_timer[index],
733                           env->last_icount + itrigger_get_count(env, index));
734             } else {
735                 env->itrigger_enabled = riscv_itrigger_enabled(env);
736             }
737         }
738         break;
739     case TDATA2:
740         qemu_log_mask(LOG_UNIMP,
741                       "tdata2 is not supported for icount trigger\n");
742         break;
743     case TDATA3:
744         qemu_log_mask(LOG_UNIMP,
745                       "tdata3 is not supported for icount trigger\n");
746         break;
747     default:
748         g_assert_not_reached();
749     }
750 
751     return;
752 }
753 
754 static int itrigger_get_adjust_count(CPURISCVState *env)
755 {
756     int count = itrigger_get_count(env, env->trigger_cur), executed;
757     if ((count != 0) && check_itrigger_priv(env, env->trigger_cur)) {
758         executed = icount_get_raw() - env->last_icount;
759         count += executed;
760     }
761     return count;
762 }
763 
764 target_ulong tdata_csr_read(CPURISCVState *env, int tdata_index)
765 {
766     int trigger_type;
767     switch (tdata_index) {
768     case TDATA1:
769         trigger_type = extract_trigger_type(env,
770                                             env->tdata1[env->trigger_cur]);
771         if ((trigger_type == TRIGGER_TYPE_INST_CNT) && icount_enabled()) {
772             return deposit64(env->tdata1[env->trigger_cur], 10, 14,
773                              itrigger_get_adjust_count(env));
774         }
775         return env->tdata1[env->trigger_cur];
776     case TDATA2:
777         return env->tdata2[env->trigger_cur];
778     case TDATA3:
779         return env->tdata3[env->trigger_cur];
780     default:
781         g_assert_not_reached();
782     }
783 }
784 
785 void tdata_csr_write(CPURISCVState *env, int tdata_index, target_ulong val)
786 {
787     int trigger_type;
788 
789     if (tdata_index == TDATA1) {
790         trigger_type = extract_trigger_type(env, val);
791     } else {
792         trigger_type = get_trigger_type(env, env->trigger_cur);
793     }
794 
795     switch (trigger_type) {
796     case TRIGGER_TYPE_AD_MATCH:
797         type2_reg_write(env, env->trigger_cur, tdata_index, val);
798         break;
799     case TRIGGER_TYPE_AD_MATCH6:
800         type6_reg_write(env, env->trigger_cur, tdata_index, val);
801         break;
802     case TRIGGER_TYPE_INST_CNT:
803         itrigger_reg_write(env, env->trigger_cur, tdata_index, val);
804         break;
805     case TRIGGER_TYPE_INT:
806     case TRIGGER_TYPE_EXCP:
807     case TRIGGER_TYPE_EXT_SRC:
808         qemu_log_mask(LOG_UNIMP, "trigger type: %d is not supported\n",
809                       trigger_type);
810         break;
811     case TRIGGER_TYPE_NO_EXIST:
812     case TRIGGER_TYPE_UNAVAIL:
813         qemu_log_mask(LOG_GUEST_ERROR, "trigger type: %d does not exit\n",
814                       trigger_type);
815         break;
816     default:
817         g_assert_not_reached();
818     }
819 }
820 
821 target_ulong tinfo_csr_read(CPURISCVState *env)
822 {
823     /* assume all triggers support the same types of triggers */
824     return BIT(TRIGGER_TYPE_AD_MATCH) |
825            BIT(TRIGGER_TYPE_AD_MATCH6);
826 }
827 
828 void riscv_cpu_debug_excp_handler(CPUState *cs)
829 {
830     RISCVCPU *cpu = RISCV_CPU(cs);
831     CPURISCVState *env = &cpu->env;
832 
833     if (cs->watchpoint_hit) {
834         if (cs->watchpoint_hit->flags & BP_CPU) {
835             do_trigger_action(env, DBG_ACTION_BP);
836         }
837     } else {
838         if (cpu_breakpoint_test(cs, env->pc, BP_CPU)) {
839             do_trigger_action(env, DBG_ACTION_BP);
840         }
841     }
842 }
843 
844 bool riscv_cpu_debug_check_breakpoint(CPUState *cs)
845 {
846     RISCVCPU *cpu = RISCV_CPU(cs);
847     CPURISCVState *env = &cpu->env;
848     CPUBreakpoint *bp;
849     target_ulong ctrl;
850     target_ulong pc;
851     int trigger_type;
852     int i;
853 
854     QTAILQ_FOREACH(bp, &cs->breakpoints, entry) {
855         for (i = 0; i < RV_MAX_TRIGGERS; i++) {
856             trigger_type = get_trigger_type(env, i);
857 
858             if (!trigger_common_match(env, trigger_type, i)) {
859                 continue;
860             }
861 
862             switch (trigger_type) {
863             case TRIGGER_TYPE_AD_MATCH:
864                 ctrl = env->tdata1[i];
865                 pc = env->tdata2[i];
866 
867                 if ((ctrl & TYPE2_EXEC) && (bp->pc == pc)) {
868                     env->badaddr = pc;
869                     return true;
870                 }
871                 break;
872             case TRIGGER_TYPE_AD_MATCH6:
873                 ctrl = env->tdata1[i];
874                 pc = env->tdata2[i];
875 
876                 if ((ctrl & TYPE6_EXEC) && (bp->pc == pc)) {
877                     env->badaddr = pc;
878                     return true;
879                 }
880                 break;
881             default:
882                 /* other trigger types are not supported or irrelevant */
883                 break;
884             }
885         }
886     }
887 
888     return false;
889 }
890 
891 bool riscv_cpu_debug_check_watchpoint(CPUState *cs, CPUWatchpoint *wp)
892 {
893     RISCVCPU *cpu = RISCV_CPU(cs);
894     CPURISCVState *env = &cpu->env;
895     target_ulong ctrl;
896     target_ulong addr;
897     int trigger_type;
898     int flags;
899     int i;
900 
901     for (i = 0; i < RV_MAX_TRIGGERS; i++) {
902         trigger_type = get_trigger_type(env, i);
903 
904         if (!trigger_common_match(env, trigger_type, i)) {
905             continue;
906         }
907 
908         switch (trigger_type) {
909         case TRIGGER_TYPE_AD_MATCH:
910             ctrl = env->tdata1[i];
911             addr = env->tdata2[i];
912             flags = 0;
913 
914             if (ctrl & TYPE2_LOAD) {
915                 flags |= BP_MEM_READ;
916             }
917             if (ctrl & TYPE2_STORE) {
918                 flags |= BP_MEM_WRITE;
919             }
920 
921             if ((wp->flags & flags) && (wp->vaddr == addr)) {
922                 return true;
923             }
924             break;
925         case TRIGGER_TYPE_AD_MATCH6:
926             ctrl = env->tdata1[i];
927             addr = env->tdata2[i];
928             flags = 0;
929 
930             if (ctrl & TYPE6_LOAD) {
931                 flags |= BP_MEM_READ;
932             }
933             if (ctrl & TYPE6_STORE) {
934                 flags |= BP_MEM_WRITE;
935             }
936 
937             if ((wp->flags & flags) && (wp->vaddr == addr)) {
938                 return true;
939             }
940             break;
941         default:
942             /* other trigger types are not supported */
943             break;
944         }
945     }
946 
947     return false;
948 }
949 
950 void riscv_trigger_realize(CPURISCVState *env)
951 {
952     int i;
953 
954     for (i = 0; i < RV_MAX_TRIGGERS; i++) {
955         env->itrigger_timer[i] = timer_new_ns(QEMU_CLOCK_VIRTUAL,
956                                               riscv_itrigger_timer_cb, env);
957     }
958 }
959 
960 void riscv_trigger_reset_hold(CPURISCVState *env)
961 {
962     target_ulong tdata1 = build_tdata1(env, TRIGGER_TYPE_AD_MATCH, 0, 0);
963     int i;
964 
965     /* init to type 2 triggers */
966     for (i = 0; i < RV_MAX_TRIGGERS; i++) {
967         /*
968          * type = TRIGGER_TYPE_AD_MATCH
969          * dmode = 0 (both debug and M-mode can write tdata)
970          * maskmax = 0 (unimplemented, always 0)
971          * sizehi = 0 (match against any size, RV64 only)
972          * hit = 0 (unimplemented, always 0)
973          * select = 0 (always 0, perform match on address)
974          * timing = 0 (always 0, trigger before instruction)
975          * sizelo = 0 (match against any size)
976          * action = 0 (always 0, raise a breakpoint exception)
977          * chain = 0 (unimplemented, always 0)
978          * match = 0 (always 0, when any compare value equals tdata2)
979          */
980         env->tdata1[i] = tdata1;
981         env->tdata2[i] = 0;
982         env->tdata3[i] = 0;
983         env->cpu_breakpoint[i] = NULL;
984         env->cpu_watchpoint[i] = NULL;
985         timer_del(env->itrigger_timer[i]);
986     }
987 
988     env->mcontext = 0;
989 }
990