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
  21 #include "hw-main.h"
  22 #include "hw-base.h"
  23
  24 #include "sim-events.h"
  25
  26 #include <string.h>
  27
  28 /* The hw-events object is implemented using sim-events */
  29
  30 struct hw_event
  31 {
  32   void *data;
  33   struct hw *me;
  34   hw_event_callback *callback;
  35   sim_event *real;
  36   struct hw_event_data *entry;
  37 };
  38
  39 struct hw_event_data
  40 {
  41   struct hw_event event;
  42   struct hw_event_data *next;
  43 };
  44
  45 void
  46 create_hw_event_data (struct hw *me)
  47 {
  48   if (me->events_of_hw != NULL)
  49     hw_abort (me, "stray events");
  50   /* NOP */
  51 }
  52
  53 void
  54 delete_hw_event_data (struct hw *me)
  55 {
  56   /* Remove the scheduled event.  */
  57   while (me->events_of_hw)
  58     hw_event_queue_deschedule (me, &me->events_of_hw->event);
  59 }
  60
  61
  62 /* Pass the H/W event onto the real callback */
  63
  64 static void
  65 bounce_hw_event (SIM_DESC sd,
  66                  void *data)
  67 {
  68   /* save the data */
  69   struct hw_event_data *entry = (struct hw_event_data *) data;
  70   struct hw *me = entry->event.me;
  71   void *event_data = entry->event.data;
  72   hw_event_callback *callback = entry->event.callback;
  73   struct hw_event_data **prev = &me->events_of_hw;
  74   while ((*prev) != entry)
  75     prev = &(*prev)->next;
  76   (*prev) = entry->next;
  77   hw_free (me, entry);
  78   callback (me, event_data); /* may not return */
  79 }
  80
  81
  82
  83 /* Map onto the event functions */
  84
  85 struct hw_event *
  86 hw_event_queue_schedule (struct hw *me,
  87                          signed64 delta_time,
  88                          hw_event_callback *callback,
  89                          void *data)
  90 {
  91   struct hw_event *event;
  92   va_list dummy;
  93   memset (&dummy, 0, sizeof dummy);
  94   event = hw_event_queue_schedule_vtracef (me, delta_time, callback, data,
  95                                            NULL, dummy);
  96   return event;
  97 }
  98
  99 struct hw_event *
 100 hw_event_queue_schedule_tracef (struct hw *me,
 101                                 signed64 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                                  signed64 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 signed64
 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 signed64
 173 hw_event_remain_time (struct hw *me, struct hw_event *event)
 174 {
 175   signed64 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 "sim-main.h"
 186 #include <string.h>
 187 #include <stdio.h>
 188 #include <stdlib.h>
 189
 190 static void
 191 test_handler (struct hw *me,
 192               void *data)
 193 {
 194   int *n = data;
 195   if (*n != hw_event_queue_time (me))
 196     abort ();
 197   *n = -(*n);
 198 }
 199
 200 int
 201 main (int argc,
 202       char **argv)
 203 {
 204   host_callback *cb = ZALLOC (host_callback);
 205   struct sim_state *sd = sim_state_alloc (0, cb);
 206   struct hw *me = ZALLOC (struct hw);
 207   sim_pre_argv_init (sd, "test-hw-events");
 208   sim_post_argv_init (sd);
 209   me->system_of_hw = sd;
 210
 211   printf ("Create hw-event-data\n");
 212   {
 213     create_hw_alloc_data (me);
 214     create_hw_event_data (me);
 215     delete_hw_event_data (me);
 216     delete_hw_alloc_data (me);
 217   }
 218
 219   printf ("Create hw-events\n");
 220   {
 221     struct hw_event *a;
 222     struct hw_event *b;
 223     struct hw_event *c;
 224     struct hw_event *d;
 225     create_hw_alloc_data (me);
 226     create_hw_event_data (me);
 227     a = hw_event_queue_schedule (me, 0, NULL, NULL);
 228     b = hw_event_queue_schedule (me, 1, NULL, NULL);
 229     c = hw_event_queue_schedule (me, 2, NULL, NULL);
 230     d = hw_event_queue_schedule (me, 1, NULL, NULL);
 231     hw_event_queue_deschedule (me, c);
 232     hw_event_queue_deschedule (me, b);
 233     hw_event_queue_deschedule (me, a);
 234     hw_event_queue_deschedule (me, d);
 235     c = HW_ZALLOC (me, struct hw_event);
 236     hw_event_queue_deschedule (me, b); /* OOPS! */
 237     hw_free (me, c);
 238     delete_hw_event_data (me);
 239     delete_hw_alloc_data (me);
 240   }
 241
 242   printf ("Schedule hw-events\n");
 243   {
 244     struct hw_event **e;
 245     int *n;
 246     int i;
 247     int nr = 4;
 248     e = HW_NZALLOC (me, struct hw_event *, nr);
 249     n = HW_NZALLOC (me, int, nr);
 250     create_hw_alloc_data (me);
 251     create_hw_event_data (me);
 252     for (i = 0; i < nr; i++)
 253       {
 254         n[i] = i;
 255         e[i] = hw_event_queue_schedule (me, i, test_handler, &n[i]);
 256       }
 257     sim_events_preprocess (sd, 1, 1);
 258     for (i = 0; i < nr; i++)
 259       {
 260         if (sim_events_tick (sd))
 261           sim_events_process (sd);
 262       }
 263     for (i = 0; i < nr; i++)
 264       {
 265         if (n[i] != -i)
 266           abort ();
 267         hw_event_queue_deschedule (me, e[i]);
 268       }
 269     hw_free (me, n);
 270     hw_free (me, e);
 271     delete_hw_event_data (me);
 272     delete_hw_alloc_data (me);
 273   }
 274
 275   return 0;
 276 }
 277 #endif