xref: /netbsd-src/external/gpl3/gdb/dist/sim/common/hw-events.c (revision 88241920d21b339bf319c0e979ffda80c49a2936)
1 /* Hardware event manager.
2    Copyright (C) 1998-2024 Free Software Foundation, Inc.
3    Contributed by Cygnus Support.
4 
5 This file is part of GDB, the GNU debugger.
6 
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
11 
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15 GNU General Public License for more details.
16 
17 You should have received a copy of the GNU General Public License
18 along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
19 
20 /* This must come before any other includes.  */
21 #include "defs.h"
22 
23 #include <stdarg.h>
24 #include <string.h>
25 
26 #include "sim/callback.h"
27 
28 #include "hw-main.h"
29 #include "hw-base.h"
30 
31 #include "sim-events.h"
32 
33 /* The hw-events object is implemented using sim-events */
34 
35 struct hw_event
36 {
37   void *data;
38   struct hw *me;
39   hw_event_callback *callback;
40   sim_event *real;
41   struct hw_event_data *entry;
42 };
43 
44 struct hw_event_data
45 {
46   struct hw_event event;
47   struct hw_event_data *next;
48 };
49 
50 void
51 create_hw_event_data (struct hw *me)
52 {
53   if (me->events_of_hw != NULL)
54     hw_abort (me, "stray events");
55   /* NOP */
56 }
57 
58 void
59 delete_hw_event_data (struct hw *me)
60 {
61   /* Remove the scheduled event.  */
62   while (me->events_of_hw)
63     hw_event_queue_deschedule (me, &me->events_of_hw->event);
64 }
65 
66 
67 /* Pass the H/W event onto the real callback */
68 
69 static void
70 bounce_hw_event (SIM_DESC sd,
71 		 void *data)
72 {
73   /* save the data */
74   struct hw_event_data *entry = (struct hw_event_data *) data;
75   struct hw *me = entry->event.me;
76   void *event_data = entry->event.data;
77   hw_event_callback *callback = entry->event.callback;
78   struct hw_event_data **prev = &me->events_of_hw;
79   while ((*prev) != entry)
80     prev = &(*prev)->next;
81   (*prev) = entry->next;
82   hw_free (me, entry);
83   callback (me, event_data); /* may not return */
84 }
85 
86 
87 
88 /* Map onto the event functions */
89 
90 struct hw_event *
91 hw_event_queue_schedule (struct hw *me,
92 			 int64_t delta_time,
93 			 hw_event_callback *callback,
94 			 void *data)
95 {
96   return hw_event_queue_schedule_tracef (me, delta_time, callback, data, NULL);
97 }
98 
99 struct hw_event *
100 hw_event_queue_schedule_tracef (struct hw *me,
101 				int64_t delta_time,
102 				hw_event_callback *callback,
103 				void *data,
104 				const char *fmt,
105 				...)
106 {
107   struct hw_event *event;
108   va_list ap;
109   va_start (ap, fmt);
110   event = hw_event_queue_schedule_vtracef (me, delta_time, callback, data, fmt, ap);
111   va_end (ap);
112   return event;
113 }
114 
115 struct hw_event *
116 hw_event_queue_schedule_vtracef (struct hw *me,
117 				 int64_t delta_time,
118 				 hw_event_callback *callback,
119 				 void *data,
120 				 const char *fmt,
121 				 va_list ap)
122 {
123   struct hw_event_data *entry = HW_ZALLOC (me, struct hw_event_data);
124   entry->next = me->events_of_hw;
125   me->events_of_hw = entry;
126   /* fill it in */
127   entry->event.entry = entry;
128   entry->event.data = data;
129   entry->event.callback = callback;
130   entry->event.me = me;
131   entry->event.real = sim_events_schedule_vtracef (hw_system (me),
132 						   delta_time,
133 						   bounce_hw_event,
134 						   entry,
135 						   fmt, ap);
136   return &entry->event;
137 }
138 
139 
140 void
141 hw_event_queue_deschedule (struct hw *me,
142 			   struct hw_event *event_to_remove)
143 {
144 /* ZAP the event but only if it is still in the event queue.  Note
145    that event_to_remove is only de-referenced after its validity has
146    been confirmed.  */
147   struct hw_event_data **prev;
148   for (prev = &me->events_of_hw;
149        (*prev) != NULL;
150        prev = &(*prev)->next)
151     {
152       struct hw_event_data *entry = (*prev);
153       if (&entry->event == event_to_remove)
154 	{
155 	  sim_events_deschedule (hw_system (me),
156 				 entry->event.real);
157 	  (*prev) = entry->next;
158 	  hw_free (me, entry);
159 	  return;
160 	}
161     }
162 }
163 
164 
165 int64_t
166 hw_event_queue_time (struct hw *me)
167 {
168   return sim_events_time (hw_system (me));
169 }
170 
171 /* Returns the time that remains before the event is raised. */
172 int64_t
173 hw_event_remain_time (struct hw *me, struct hw_event *event)
174 {
175   int64_t t;
176 
177   t = sim_events_remain_time (hw_system (me), event->real);
178   return t;
179 }
180 
181 /* Only worry about this compling on ANSI systems.
182    Build with `make test-hw-events' in sim/<cpu> directory*/
183 
184 #if defined (MAIN)
185 #include <stdio.h>
186 #include <stdlib.h>
187 #include <string.h>
188 
189 #include "sim-main.h"
190 
191 static void
192 test_handler (struct hw *me,
193 	      void *data)
194 {
195   int *n = data;
196   if (*n != hw_event_queue_time (me))
197     abort ();
198   *n = -(*n);
199 }
200 
201 int
202 main (int argc,
203       char **argv)
204 {
205   host_callback *cb = ZALLOC (host_callback);
206   struct sim_state *sd = sim_state_alloc (0, cb);
207   struct hw *me = ZALLOC (struct hw);
208   sim_pre_argv_init (sd, "test-hw-events");
209   sim_post_argv_init (sd);
210   me->system_of_hw = sd;
211 
212   printf ("Create hw-event-data\n");
213   {
214     create_hw_alloc_data (me);
215     create_hw_event_data (me);
216     delete_hw_event_data (me);
217     delete_hw_alloc_data (me);
218   }
219 
220   printf ("Create hw-events\n");
221   {
222     struct hw_event *a;
223     struct hw_event *b;
224     struct hw_event *c;
225     struct hw_event *d;
226     create_hw_alloc_data (me);
227     create_hw_event_data (me);
228     a = hw_event_queue_schedule (me, 0, NULL, NULL);
229     b = hw_event_queue_schedule (me, 1, NULL, NULL);
230     c = hw_event_queue_schedule (me, 2, NULL, NULL);
231     d = hw_event_queue_schedule (me, 1, NULL, NULL);
232     hw_event_queue_deschedule (me, c);
233     hw_event_queue_deschedule (me, b);
234     hw_event_queue_deschedule (me, a);
235     hw_event_queue_deschedule (me, d);
236     c = HW_ZALLOC (me, struct hw_event);
237     hw_event_queue_deschedule (me, b); /* OOPS! */
238     hw_free (me, c);
239     delete_hw_event_data (me);
240     delete_hw_alloc_data (me);
241   }
242 
243   printf ("Schedule hw-events\n");
244   {
245     struct hw_event **e;
246     int *n;
247     int i;
248     int nr = 4;
249     e = HW_NZALLOC (me, struct hw_event *, nr);
250     n = HW_NZALLOC (me, int, nr);
251     create_hw_alloc_data (me);
252     create_hw_event_data (me);
253     for (i = 0; i < nr; i++)
254       {
255 	n[i] = i;
256 	e[i] = hw_event_queue_schedule (me, i, test_handler, &n[i]);
257       }
258     sim_events_preprocess (sd, 1, 1);
259     for (i = 0; i < nr; i++)
260       {
261 	if (sim_events_tick (sd))
262 	  sim_events_process (sd);
263       }
264     for (i = 0; i < nr; i++)
265       {
266 	if (n[i] != -i)
267 	  abort ();
268 	hw_event_queue_deschedule (me, e[i]);
269       }
270     hw_free (me, n);
271     hw_free (me, e);
272     delete_hw_event_data (me);
273     delete_hw_alloc_data (me);
274   }
275 
276   return 0;
277 }
278 #endif
279