xref: /netbsd-src/external/gpl3/gdb/dist/sim/common/hw-events.c (revision 82d56013d7b633d116a93943de88e08335357a7c)
1 /* Hardware event manager.
2    Copyright (C) 1998-2020 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 
21 #include "hw-main.h"
22 #include "hw-base.h"
23 
24 #include "sim-events.h"
25 
26 #if HAVE_STRING_H
27 #include <string.h>
28 #endif
29 
30 /* The hw-events object is implemented using sim-events */
31 
32 struct hw_event
33 {
34   void *data;
35   struct hw *me;
36   hw_event_callback *callback;
37   sim_event *real;
38   struct hw_event_data *entry;
39 };
40 
41 struct hw_event_data
42 {
43   struct hw_event event;
44   struct hw_event_data *next;
45 };
46 
47 void
48 create_hw_event_data (struct hw *me)
49 {
50   if (me->events_of_hw != NULL)
51     hw_abort (me, "stray events");
52   /* NOP */
53 }
54 
55 void
56 delete_hw_event_data (struct hw *me)
57 {
58   /* Remove the scheduled event.  */
59   while (me->events_of_hw)
60     hw_event_queue_deschedule (me, &me->events_of_hw->event);
61 }
62 
63 
64 /* Pass the H/W event onto the real callback */
65 
66 static void
67 bounce_hw_event (SIM_DESC sd,
68 		 void *data)
69 {
70   /* save the data */
71   struct hw_event_data *entry = (struct hw_event_data *) data;
72   struct hw *me = entry->event.me;
73   void *event_data = entry->event.data;
74   hw_event_callback *callback = entry->event.callback;
75   struct hw_event_data **prev = &me->events_of_hw;
76   while ((*prev) != entry)
77     prev = &(*prev)->next;
78   (*prev) = entry->next;
79   hw_free (me, entry);
80   callback (me, event_data); /* may not return */
81 }
82 
83 
84 
85 /* Map onto the event functions */
86 
87 struct hw_event *
88 hw_event_queue_schedule (struct hw *me,
89 			 signed64 delta_time,
90 			 hw_event_callback *callback,
91 			 void *data)
92 {
93   struct hw_event *event;
94   va_list dummy;
95   memset (&dummy, 0, sizeof dummy);
96   event = hw_event_queue_schedule_vtracef (me, delta_time, callback, data,
97 					   NULL, dummy);
98   return event;
99 }
100 
101 struct hw_event *
102 hw_event_queue_schedule_tracef (struct hw *me,
103 				signed64 delta_time,
104 				hw_event_callback *callback,
105 				void *data,
106 				const char *fmt,
107 				...)
108 {
109   struct hw_event *event;
110   va_list ap;
111   va_start (ap, fmt);
112   event = hw_event_queue_schedule_vtracef (me, delta_time, callback, data, fmt, ap);
113   va_end (ap);
114   return event;
115 }
116 
117 struct hw_event *
118 hw_event_queue_schedule_vtracef (struct hw *me,
119 				 signed64 delta_time,
120 				 hw_event_callback *callback,
121 				 void *data,
122 				 const char *fmt,
123 				 va_list ap)
124 {
125   struct hw_event_data *entry = HW_ZALLOC (me, struct hw_event_data);
126   entry->next = me->events_of_hw;
127   me->events_of_hw = entry;
128   /* fill it in */
129   entry->event.entry = entry;
130   entry->event.data = data;
131   entry->event.callback = callback;
132   entry->event.me = me;
133   entry->event.real = sim_events_schedule_vtracef (hw_system (me),
134 						   delta_time,
135 						   bounce_hw_event,
136 						   entry,
137 						   fmt, ap);
138   return &entry->event;
139 }
140 
141 
142 void
143 hw_event_queue_deschedule (struct hw *me,
144 			   struct hw_event *event_to_remove)
145 {
146 /* ZAP the event but only if it is still in the event queue.  Note
147    that event_to_remove is only de-referenced after its validity has
148    been confirmed.  */
149   struct hw_event_data **prev;
150   for (prev = &me->events_of_hw;
151        (*prev) != NULL;
152        prev = &(*prev)->next)
153     {
154       struct hw_event_data *entry = (*prev);
155       if (&entry->event == event_to_remove)
156 	{
157 	  sim_events_deschedule (hw_system (me),
158 				 entry->event.real);
159 	  (*prev) = entry->next;
160 	  hw_free (me, entry);
161 	  return;
162 	}
163     }
164 }
165 
166 
167 signed64
168 hw_event_queue_time (struct hw *me)
169 {
170   return sim_events_time (hw_system (me));
171 }
172 
173 /* Returns the time that remains before the event is raised. */
174 signed64
175 hw_event_remain_time (struct hw *me, struct hw_event *event)
176 {
177   signed64 t;
178 
179   t = sim_events_remain_time (hw_system (me), event->real);
180   return t;
181 }
182 
183 /* Only worry about this compling on ANSI systems.
184    Build with `make test-hw-events' in sim/<cpu> directory*/
185 
186 #if defined (MAIN)
187 #include "sim-main.h"
188 #include <string.h>
189 #include <stdio.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