sim/common/hw-events.c

   1 /* Hardware event manager.
   2    Copyright (C) 1998-2021 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 "hw-main.h"
  24 #include "hw-base.h"
  25
  26 #include "sim-events.h"
  27
  28 #include <string.h>
  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   return hw_event_queue_schedule_tracef (me, delta_time, callback, data, NULL);
  94 }
  95
  96 struct hw_event *
  97 hw_event_queue_schedule_tracef (struct hw *me,
  98                                 signed64 delta_time,
  99                                 hw_event_callback *callback,
 100                                 void *data,
 101                                 const char *fmt,
 102                                 ...)
 103 {
 104   struct hw_event *event;
 105   va_list ap;
 106   va_start (ap, fmt);
 107   event = hw_event_queue_schedule_vtracef (me, delta_time, callback, data, fmt, ap);
 108   va_end (ap);
 109   return event;
 110 }
 111
 112 struct hw_event *
 113 hw_event_queue_schedule_vtracef (struct hw *me,
 114                                  signed64 delta_time,
 115                                  hw_event_callback *callback,
 116                                  void *data,
 117                                  const char *fmt,
 118                                  va_list ap)
 119 {
 120   struct hw_event_data *entry = HW_ZALLOC (me, struct hw_event_data);
 121   entry->next = me->events_of_hw;
 122   me->events_of_hw = entry;
 123   /* fill it in */
 124   entry->event.entry = entry;
 125   entry->event.data = data;
 126   entry->event.callback = callback;
 127   entry->event.me = me;
 128   entry->event.real = sim_events_schedule_vtracef (hw_system (me),
 129                                                    delta_time,
 130                                                    bounce_hw_event,
 131                                                    entry,
 132                                                    fmt, ap);
 133   return &entry->event;
 134 }
 135
 136
 137 void
 138 hw_event_queue_deschedule (struct hw *me,
 139                            struct hw_event *event_to_remove)
 140 {
 141 /* ZAP the event but only if it is still in the event queue.  Note
 142    that event_to_remove is only de-referenced after its validity has
 143    been confirmed.  */
 144   struct hw_event_data **prev;
 145   for (prev = &me->events_of_hw;
 146        (*prev) != NULL;
 147        prev = &(*prev)->next)
 148     {
 149       struct hw_event_data *entry = (*prev);
 150       if (&entry->event == event_to_remove)
 151         {
 152           sim_events_deschedule (hw_system (me),
 153                                  entry->event.real);
 154           (*prev) = entry->next;
 155           hw_free (me, entry);
 156           return;
 157         }
 158     }
 159 }
 160
 161
 162 signed64
 163 hw_event_queue_time (struct hw *me)
 164 {
 165   return sim_events_time (hw_system (me));
 166 }
 167
 168 /* Returns the time that remains before the event is raised. */
 169 signed64
 170 hw_event_remain_time (struct hw *me, struct hw_event *event)
 171 {
 172   signed64 t;
 173
 174   t = sim_events_remain_time (hw_system (me), event->real);
 175   return t;
 176 }
 177
 178 /* Only worry about this compling on ANSI systems.
 179    Build with `make test-hw-events' in sim/<cpu> directory*/
 180
 181 #if defined (MAIN)
 182 #include "sim-main.h"
 183 #include <string.h>
 184 #include <stdio.h>
 185 #include <stdlib.h>
 186
 187 static void
 188 test_handler (struct hw *me,
 189               void *data)
 190 {
 191   int *n = data;
 192   if (*n != hw_event_queue_time (me))
 193     abort ();
 194   *n = -(*n);
 195 }
 196
 197 int
 198 main (int argc,
 199       char **argv)
 200 {
 201   host_callback *cb = ZALLOC (host_callback);
 202   struct sim_state *sd = sim_state_alloc (0, cb);
 203   struct hw *me = ZALLOC (struct hw);
 204   sim_pre_argv_init (sd, "test-hw-events");
 205   sim_post_argv_init (sd);
 206   me->system_of_hw = sd;
 207
 208   printf ("Create hw-event-data\n");
 209   {
 210     create_hw_alloc_data (me);
 211     create_hw_event_data (me);
 212     delete_hw_event_data (me);
 213     delete_hw_alloc_data (me);
 214   }
 215
 216   printf ("Create hw-events\n");
 217   {
 218     struct hw_event *a;
 219     struct hw_event *b;
 220     struct hw_event *c;
 221     struct hw_event *d;
 222     create_hw_alloc_data (me);
 223     create_hw_event_data (me);
 224     a = hw_event_queue_schedule (me, 0, NULL, NULL);
 225     b = hw_event_queue_schedule (me, 1, NULL, NULL);
 226     c = hw_event_queue_schedule (me, 2, NULL, NULL);
 227     d = hw_event_queue_schedule (me, 1, NULL, NULL);
 228     hw_event_queue_deschedule (me, c);
 229     hw_event_queue_deschedule (me, b);
 230     hw_event_queue_deschedule (me, a);
 231     hw_event_queue_deschedule (me, d);
 232     c = HW_ZALLOC (me, struct hw_event);
 233     hw_event_queue_deschedule (me, b); /* OOPS! */
 234     hw_free (me, c);
 235     delete_hw_event_data (me);
 236     delete_hw_alloc_data (me);
 237   }
 238
 239   printf ("Schedule hw-events\n");
 240   {
 241     struct hw_event **e;
 242     int *n;
 243     int i;
 244     int nr = 4;
 245     e = HW_NZALLOC (me, struct hw_event *, nr);
 246     n = HW_NZALLOC (me, int, nr);
 247     create_hw_alloc_data (me);
 248     create_hw_event_data (me);
 249     for (i = 0; i < nr; i++)
 250       {
 251         n[i] = i;
 252         e[i] = hw_event_queue_schedule (me, i, test_handler, &n[i]);
 253       }
 254     sim_events_preprocess (sd, 1, 1);
 255     for (i = 0; i < nr; i++)
 256       {
 257         if (sim_events_tick (sd))
 258           sim_events_process (sd);
 259       }
 260     for (i = 0; i < nr; i++)
 261       {
 262         if (n[i] != -i)
 263           abort ();
 264         hw_event_queue_deschedule (me, e[i]);
 265       }
 266     hw_free (me, n);
 267     hw_free (me, e);
 268     delete_hw_event_data (me);
 269     delete_hw_alloc_data (me);
 270   }
 271
 272   return 0;
 273 }
 274 #endif