sim/common/hw-events.c

   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