xref: /openbmc/qemu/target/riscv/debug.c (revision 5a4ae64c)
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 /* type 2 trigger */
245 
246 static uint32_t type2_breakpoint_size(CPURISCVState *env, target_ulong ctrl)
247 {
248     uint32_t sizelo, sizehi = 0;
249 
250     if (riscv_cpu_mxl(env) == MXL_RV64) {
251         sizehi = extract32(ctrl, 21, 2);
252     }
253     sizelo = extract32(ctrl, 16, 2);
254     return (sizehi << 2) | sizelo;
255 }
256 
257 static inline bool type2_breakpoint_enabled(target_ulong ctrl)
258 {
259     bool mode = !!(ctrl & (TYPE2_U | TYPE2_S | TYPE2_M));
260     bool rwx = !!(ctrl & (TYPE2_LOAD | TYPE2_STORE | TYPE2_EXEC));
261 
262     return mode && rwx;
263 }
264 
265 static target_ulong type2_mcontrol_validate(CPURISCVState *env,
266                                             target_ulong ctrl)
267 {
268     target_ulong val;
269     uint32_t size;
270 
271     /* validate the generic part first */
272     val = tdata1_validate(env, ctrl, TRIGGER_TYPE_AD_MATCH);
273 
274     /* validate unimplemented (always zero) bits */
275     warn_always_zero_bit(ctrl, TYPE2_MATCH, "match");
276     warn_always_zero_bit(ctrl, TYPE2_CHAIN, "chain");
277     warn_always_zero_bit(ctrl, TYPE2_ACTION, "action");
278     warn_always_zero_bit(ctrl, TYPE2_TIMING, "timing");
279     warn_always_zero_bit(ctrl, TYPE2_SELECT, "select");
280     warn_always_zero_bit(ctrl, TYPE2_HIT, "hit");
281 
282     /* validate size encoding */
283     size = type2_breakpoint_size(env, ctrl);
284     if (access_size[size] == -1) {
285         qemu_log_mask(LOG_UNIMP, "access size %d is not supported, using SIZE_ANY\n",
286                       size);
287     } else {
288         val |= (ctrl & TYPE2_SIZELO);
289         if (riscv_cpu_mxl(env) == MXL_RV64) {
290             val |= (ctrl & TYPE2_SIZEHI);
291         }
292     }
293 
294     /* keep the mode and attribute bits */
295     val |= (ctrl & (TYPE2_U | TYPE2_S | TYPE2_M |
296                     TYPE2_LOAD | TYPE2_STORE | TYPE2_EXEC));
297 
298     return val;
299 }
300 
301 static void type2_breakpoint_insert(CPURISCVState *env, target_ulong index)
302 {
303     target_ulong ctrl = env->tdata1[index];
304     target_ulong addr = env->tdata2[index];
305     bool enabled = type2_breakpoint_enabled(ctrl);
306     CPUState *cs = env_cpu(env);
307     int flags = BP_CPU | BP_STOP_BEFORE_ACCESS;
308     uint32_t size;
309 
310     if (!enabled) {
311         return;
312     }
313 
314     if (ctrl & TYPE2_EXEC) {
315         cpu_breakpoint_insert(cs, addr, flags, &env->cpu_breakpoint[index]);
316     }
317 
318     if (ctrl & TYPE2_LOAD) {
319         flags |= BP_MEM_READ;
320     }
321     if (ctrl & TYPE2_STORE) {
322         flags |= BP_MEM_WRITE;
323     }
324 
325     if (flags & BP_MEM_ACCESS) {
326         size = type2_breakpoint_size(env, ctrl);
327         if (size != 0) {
328             cpu_watchpoint_insert(cs, addr, size, flags,
329                                   &env->cpu_watchpoint[index]);
330         } else {
331             cpu_watchpoint_insert(cs, addr, 8, flags,
332                                   &env->cpu_watchpoint[index]);
333         }
334     }
335 }
336 
337 static void type2_breakpoint_remove(CPURISCVState *env, target_ulong index)
338 {
339     CPUState *cs = env_cpu(env);
340 
341     if (env->cpu_breakpoint[index]) {
342         cpu_breakpoint_remove_by_ref(cs, env->cpu_breakpoint[index]);
343         env->cpu_breakpoint[index] = NULL;
344     }
345 
346     if (env->cpu_watchpoint[index]) {
347         cpu_watchpoint_remove_by_ref(cs, env->cpu_watchpoint[index]);
348         env->cpu_watchpoint[index] = NULL;
349     }
350 }
351 
352 static void type2_reg_write(CPURISCVState *env, target_ulong index,
353                             int tdata_index, target_ulong val)
354 {
355     target_ulong new_val;
356 
357     switch (tdata_index) {
358     case TDATA1:
359         new_val = type2_mcontrol_validate(env, val);
360         if (new_val != env->tdata1[index]) {
361             env->tdata1[index] = new_val;
362             type2_breakpoint_remove(env, index);
363             type2_breakpoint_insert(env, index);
364         }
365         break;
366     case TDATA2:
367         if (val != env->tdata2[index]) {
368             env->tdata2[index] = val;
369             type2_breakpoint_remove(env, index);
370             type2_breakpoint_insert(env, index);
371         }
372         break;
373     case TDATA3:
374         qemu_log_mask(LOG_UNIMP,
375                       "tdata3 is not supported for type 2 trigger\n");
376         break;
377     default:
378         g_assert_not_reached();
379     }
380 
381     return;
382 }
383 
384 /* type 6 trigger */
385 
386 static inline bool type6_breakpoint_enabled(target_ulong ctrl)
387 {
388     bool mode = !!(ctrl & (TYPE6_VU | TYPE6_VS | TYPE6_U | TYPE6_S | TYPE6_M));
389     bool rwx = !!(ctrl & (TYPE6_LOAD | TYPE6_STORE | TYPE6_EXEC));
390 
391     return mode && rwx;
392 }
393 
394 static target_ulong type6_mcontrol6_validate(CPURISCVState *env,
395                                              target_ulong ctrl)
396 {
397     target_ulong val;
398     uint32_t size;
399 
400     /* validate the generic part first */
401     val = tdata1_validate(env, ctrl, TRIGGER_TYPE_AD_MATCH6);
402 
403     /* validate unimplemented (always zero) bits */
404     warn_always_zero_bit(ctrl, TYPE6_MATCH, "match");
405     warn_always_zero_bit(ctrl, TYPE6_CHAIN, "chain");
406     warn_always_zero_bit(ctrl, TYPE6_ACTION, "action");
407     warn_always_zero_bit(ctrl, TYPE6_TIMING, "timing");
408     warn_always_zero_bit(ctrl, TYPE6_SELECT, "select");
409     warn_always_zero_bit(ctrl, TYPE6_HIT, "hit");
410 
411     /* validate size encoding */
412     size = extract32(ctrl, 16, 4);
413     if (access_size[size] == -1) {
414         qemu_log_mask(LOG_UNIMP, "access size %d is not supported, using SIZE_ANY\n",
415                       size);
416     } else {
417         val |= (ctrl & TYPE6_SIZE);
418     }
419 
420     /* keep the mode and attribute bits */
421     val |= (ctrl & (TYPE6_VU | TYPE6_VS | TYPE6_U | TYPE6_S | TYPE6_M |
422                     TYPE6_LOAD | TYPE6_STORE | TYPE6_EXEC));
423 
424     return val;
425 }
426 
427 static void type6_breakpoint_insert(CPURISCVState *env, target_ulong index)
428 {
429     target_ulong ctrl = env->tdata1[index];
430     target_ulong addr = env->tdata2[index];
431     bool enabled = type6_breakpoint_enabled(ctrl);
432     CPUState *cs = env_cpu(env);
433     int flags = BP_CPU | BP_STOP_BEFORE_ACCESS;
434     uint32_t size;
435 
436     if (!enabled) {
437         return;
438     }
439 
440     if (ctrl & TYPE6_EXEC) {
441         cpu_breakpoint_insert(cs, addr, flags, &env->cpu_breakpoint[index]);
442     }
443 
444     if (ctrl & TYPE6_LOAD) {
445         flags |= BP_MEM_READ;
446     }
447 
448     if (ctrl & TYPE6_STORE) {
449         flags |= BP_MEM_WRITE;
450     }
451 
452     if (flags & BP_MEM_ACCESS) {
453         size = extract32(ctrl, 16, 4);
454         if (size != 0) {
455             cpu_watchpoint_insert(cs, addr, size, flags,
456                                   &env->cpu_watchpoint[index]);
457         } else {
458             cpu_watchpoint_insert(cs, addr, 8, flags,
459                                   &env->cpu_watchpoint[index]);
460         }
461     }
462 }
463 
464 static void type6_breakpoint_remove(CPURISCVState *env, target_ulong index)
465 {
466     type2_breakpoint_remove(env, index);
467 }
468 
469 static void type6_reg_write(CPURISCVState *env, target_ulong index,
470                             int tdata_index, target_ulong val)
471 {
472     target_ulong new_val;
473 
474     switch (tdata_index) {
475     case TDATA1:
476         new_val = type6_mcontrol6_validate(env, val);
477         if (new_val != env->tdata1[index]) {
478             env->tdata1[index] = new_val;
479             type6_breakpoint_remove(env, index);
480             type6_breakpoint_insert(env, index);
481         }
482         break;
483     case TDATA2:
484         if (val != env->tdata2[index]) {
485             env->tdata2[index] = val;
486             type6_breakpoint_remove(env, index);
487             type6_breakpoint_insert(env, index);
488         }
489         break;
490     case TDATA3:
491         qemu_log_mask(LOG_UNIMP,
492                       "tdata3 is not supported for type 6 trigger\n");
493         break;
494     default:
495         g_assert_not_reached();
496     }
497 
498     return;
499 }
500 
501 /* icount trigger type */
502 static inline int
503 itrigger_get_count(CPURISCVState *env, int index)
504 {
505     return get_field(env->tdata1[index], ITRIGGER_COUNT);
506 }
507 
508 static inline void
509 itrigger_set_count(CPURISCVState *env, int index, int value)
510 {
511     env->tdata1[index] = set_field(env->tdata1[index],
512                                    ITRIGGER_COUNT, value);
513 }
514 
515 static bool check_itrigger_priv(CPURISCVState *env, int index)
516 {
517     target_ulong tdata1 = env->tdata1[index];
518     if (riscv_cpu_virt_enabled(env)) {
519         /* check VU/VS bit against current privilege level */
520         return (get_field(tdata1, ITRIGGER_VS) == env->priv) ||
521                (get_field(tdata1, ITRIGGER_VU) == env->priv);
522     } else {
523         /* check U/S/M bit against current privilege level */
524         return (get_field(tdata1, ITRIGGER_M) == env->priv) ||
525                (get_field(tdata1, ITRIGGER_S) == env->priv) ||
526                (get_field(tdata1, ITRIGGER_U) == env->priv);
527     }
528 }
529 
530 bool riscv_itrigger_enabled(CPURISCVState *env)
531 {
532     int count;
533     for (int i = 0; i < RV_MAX_TRIGGERS; i++) {
534         if (get_trigger_type(env, i) != TRIGGER_TYPE_INST_CNT) {
535             continue;
536         }
537         if (check_itrigger_priv(env, i)) {
538             continue;
539         }
540         count = itrigger_get_count(env, i);
541         if (!count) {
542             continue;
543         }
544         return true;
545     }
546 
547     return false;
548 }
549 
550 void helper_itrigger_match(CPURISCVState *env)
551 {
552     int count;
553     for (int i = 0; i < RV_MAX_TRIGGERS; i++) {
554         if (get_trigger_type(env, i) != TRIGGER_TYPE_INST_CNT) {
555             continue;
556         }
557         if (check_itrigger_priv(env, i)) {
558             continue;
559         }
560         count = itrigger_get_count(env, i);
561         if (!count) {
562             continue;
563         }
564         itrigger_set_count(env, i, count--);
565         if (!count) {
566             do_trigger_action(env, i);
567         }
568     }
569 }
570 
571 static void riscv_itrigger_update_count(CPURISCVState *env)
572 {
573     int count, executed;
574     /*
575      * Record last icount, so that we can evaluate the executed instructions
576      * since last priviledge mode change or timer expire.
577      */
578     int64_t last_icount = env->last_icount, current_icount;
579     current_icount = env->last_icount = icount_get_raw();
580 
581     for (int i = 0; i < RV_MAX_TRIGGERS; i++) {
582         if (get_trigger_type(env, i) != TRIGGER_TYPE_INST_CNT) {
583             continue;
584         }
585         count = itrigger_get_count(env, i);
586         if (!count) {
587             continue;
588         }
589         /*
590          * Only when priviledge is changed or itrigger timer expires,
591          * the count field in itrigger tdata1 register is updated.
592          * And the count field in itrigger only contains remaining value.
593          */
594         if (check_itrigger_priv(env, i)) {
595             /*
596              * If itrigger enabled in this priviledge mode, the number of
597              * executed instructions since last priviledge change
598              * should be reduced from current itrigger count.
599              */
600             executed = current_icount - last_icount;
601             itrigger_set_count(env, i, count - executed);
602             if (count == executed) {
603                 do_trigger_action(env, i);
604             }
605         } else {
606             /*
607              * If itrigger is not enabled in this priviledge mode,
608              * the number of executed instructions will be discard and
609              * the count field in itrigger will not change.
610              */
611             timer_mod(env->itrigger_timer[i],
612                       current_icount + count);
613         }
614     }
615 }
616 
617 static void riscv_itrigger_timer_cb(void *opaque)
618 {
619     riscv_itrigger_update_count((CPURISCVState *)opaque);
620 }
621 
622 void riscv_itrigger_update_priv(CPURISCVState *env)
623 {
624     riscv_itrigger_update_count(env);
625 }
626 
627 target_ulong tdata_csr_read(CPURISCVState *env, int tdata_index)
628 {
629     switch (tdata_index) {
630     case TDATA1:
631         return env->tdata1[env->trigger_cur];
632     case TDATA2:
633         return env->tdata2[env->trigger_cur];
634     case TDATA3:
635         return env->tdata3[env->trigger_cur];
636     default:
637         g_assert_not_reached();
638     }
639 }
640 
641 void tdata_csr_write(CPURISCVState *env, int tdata_index, target_ulong val)
642 {
643     int trigger_type;
644 
645     if (tdata_index == TDATA1) {
646         trigger_type = extract_trigger_type(env, val);
647     } else {
648         trigger_type = get_trigger_type(env, env->trigger_cur);
649     }
650 
651     switch (trigger_type) {
652     case TRIGGER_TYPE_AD_MATCH:
653         type2_reg_write(env, env->trigger_cur, tdata_index, val);
654         break;
655     case TRIGGER_TYPE_AD_MATCH6:
656         type6_reg_write(env, env->trigger_cur, tdata_index, val);
657         break;
658     case TRIGGER_TYPE_INST_CNT:
659     case TRIGGER_TYPE_INT:
660     case TRIGGER_TYPE_EXCP:
661     case TRIGGER_TYPE_EXT_SRC:
662         qemu_log_mask(LOG_UNIMP, "trigger type: %d is not supported\n",
663                       trigger_type);
664         break;
665     case TRIGGER_TYPE_NO_EXIST:
666     case TRIGGER_TYPE_UNAVAIL:
667         qemu_log_mask(LOG_GUEST_ERROR, "trigger type: %d does not exit\n",
668                       trigger_type);
669         break;
670     default:
671         g_assert_not_reached();
672     }
673 }
674 
675 target_ulong tinfo_csr_read(CPURISCVState *env)
676 {
677     /* assume all triggers support the same types of triggers */
678     return BIT(TRIGGER_TYPE_AD_MATCH) |
679            BIT(TRIGGER_TYPE_AD_MATCH6);
680 }
681 
682 void riscv_cpu_debug_excp_handler(CPUState *cs)
683 {
684     RISCVCPU *cpu = RISCV_CPU(cs);
685     CPURISCVState *env = &cpu->env;
686 
687     if (cs->watchpoint_hit) {
688         if (cs->watchpoint_hit->flags & BP_CPU) {
689             cs->watchpoint_hit = NULL;
690             do_trigger_action(env, DBG_ACTION_BP);
691         }
692     } else {
693         if (cpu_breakpoint_test(cs, env->pc, BP_CPU)) {
694             do_trigger_action(env, DBG_ACTION_BP);
695         }
696     }
697 }
698 
699 bool riscv_cpu_debug_check_breakpoint(CPUState *cs)
700 {
701     RISCVCPU *cpu = RISCV_CPU(cs);
702     CPURISCVState *env = &cpu->env;
703     CPUBreakpoint *bp;
704     target_ulong ctrl;
705     target_ulong pc;
706     int trigger_type;
707     int i;
708 
709     QTAILQ_FOREACH(bp, &cs->breakpoints, entry) {
710         for (i = 0; i < RV_MAX_TRIGGERS; i++) {
711             trigger_type = get_trigger_type(env, i);
712 
713             switch (trigger_type) {
714             case TRIGGER_TYPE_AD_MATCH:
715                 /* type 2 trigger cannot be fired in VU/VS mode */
716                 if (riscv_cpu_virt_enabled(env)) {
717                     return false;
718                 }
719 
720                 ctrl = env->tdata1[i];
721                 pc = env->tdata2[i];
722 
723                 if ((ctrl & TYPE2_EXEC) && (bp->pc == pc)) {
724                     /* check U/S/M bit against current privilege level */
725                     if ((ctrl >> 3) & BIT(env->priv)) {
726                         return true;
727                     }
728                 }
729                 break;
730             case TRIGGER_TYPE_AD_MATCH6:
731                 ctrl = env->tdata1[i];
732                 pc = env->tdata2[i];
733 
734                 if ((ctrl & TYPE6_EXEC) && (bp->pc == pc)) {
735                     if (riscv_cpu_virt_enabled(env)) {
736                         /* check VU/VS bit against current privilege level */
737                         if ((ctrl >> 23) & BIT(env->priv)) {
738                             return true;
739                         }
740                     } else {
741                         /* check U/S/M bit against current privilege level */
742                         if ((ctrl >> 3) & BIT(env->priv)) {
743                             return true;
744                         }
745                     }
746                 }
747                 break;
748             default:
749                 /* other trigger types are not supported or irrelevant */
750                 break;
751             }
752         }
753     }
754 
755     return false;
756 }
757 
758 bool riscv_cpu_debug_check_watchpoint(CPUState *cs, CPUWatchpoint *wp)
759 {
760     RISCVCPU *cpu = RISCV_CPU(cs);
761     CPURISCVState *env = &cpu->env;
762     target_ulong ctrl;
763     target_ulong addr;
764     int trigger_type;
765     int flags;
766     int i;
767 
768     for (i = 0; i < RV_MAX_TRIGGERS; i++) {
769         trigger_type = get_trigger_type(env, i);
770 
771         switch (trigger_type) {
772         case TRIGGER_TYPE_AD_MATCH:
773             /* type 2 trigger cannot be fired in VU/VS mode */
774             if (riscv_cpu_virt_enabled(env)) {
775                 return false;
776             }
777 
778             ctrl = env->tdata1[i];
779             addr = env->tdata2[i];
780             flags = 0;
781 
782             if (ctrl & TYPE2_LOAD) {
783                 flags |= BP_MEM_READ;
784             }
785             if (ctrl & TYPE2_STORE) {
786                 flags |= BP_MEM_WRITE;
787             }
788 
789             if ((wp->flags & flags) && (wp->vaddr == addr)) {
790                 /* check U/S/M bit against current privilege level */
791                 if ((ctrl >> 3) & BIT(env->priv)) {
792                     return true;
793                 }
794             }
795             break;
796         case TRIGGER_TYPE_AD_MATCH6:
797             ctrl = env->tdata1[i];
798             addr = env->tdata2[i];
799             flags = 0;
800 
801             if (ctrl & TYPE6_LOAD) {
802                 flags |= BP_MEM_READ;
803             }
804             if (ctrl & TYPE6_STORE) {
805                 flags |= BP_MEM_WRITE;
806             }
807 
808             if ((wp->flags & flags) && (wp->vaddr == addr)) {
809                 if (riscv_cpu_virt_enabled(env)) {
810                     /* check VU/VS bit against current privilege level */
811                     if ((ctrl >> 23) & BIT(env->priv)) {
812                         return true;
813                     }
814                 } else {
815                     /* check U/S/M bit against current privilege level */
816                     if ((ctrl >> 3) & BIT(env->priv)) {
817                         return true;
818                     }
819                 }
820             }
821             break;
822         default:
823             /* other trigger types are not supported */
824             break;
825         }
826     }
827 
828     return false;
829 }
830 
831 void riscv_trigger_init(CPURISCVState *env)
832 {
833     target_ulong tdata1 = build_tdata1(env, TRIGGER_TYPE_AD_MATCH, 0, 0);
834     int i;
835 
836     /* init to type 2 triggers */
837     for (i = 0; i < RV_MAX_TRIGGERS; i++) {
838         /*
839          * type = TRIGGER_TYPE_AD_MATCH
840          * dmode = 0 (both debug and M-mode can write tdata)
841          * maskmax = 0 (unimplemented, always 0)
842          * sizehi = 0 (match against any size, RV64 only)
843          * hit = 0 (unimplemented, always 0)
844          * select = 0 (always 0, perform match on address)
845          * timing = 0 (always 0, trigger before instruction)
846          * sizelo = 0 (match against any size)
847          * action = 0 (always 0, raise a breakpoint exception)
848          * chain = 0 (unimplemented, always 0)
849          * match = 0 (always 0, when any compare value equals tdata2)
850          */
851         env->tdata1[i] = tdata1;
852         env->tdata2[i] = 0;
853         env->tdata3[i] = 0;
854         env->cpu_breakpoint[i] = NULL;
855         env->cpu_watchpoint[i] = NULL;
856         env->itrigger_timer[i] = timer_new_ns(QEMU_CLOCK_VIRTUAL,
857                                               riscv_itrigger_timer_cb, env);
858     }
859 }
860