src/sim/Root.py

   1 # Copyright (c) 2005-2007 The Regents of The University of Michigan
   2 # Copyright (c) 2010-2013 Advanced Micro Devices, Inc.
   3 # Copyright (c) 2013 Mark D. Hill and David A. Wood
   4 # All rights reserved.
   5 #
   6 # Redistribution and use in source and binary forms, with or without
   7 # modification, are permitted provided that the following conditions are
   8 # met: redistributions of source code must retain the above copyright
   9 # notice, this list of conditions and the following disclaimer;
  10 # redistributions in binary form must reproduce the above copyright
  11 # notice, this list of conditions and the following disclaimer in the
  12 # documentation and/or other materials provided with the distribution;
  13 # neither the name of the copyright holders nor the names of its
  14 # contributors may be used to endorse or promote products derived from
  15 # this software without specific prior written permission.
  16 #
  17 # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  18 # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  19 # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  20 # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  21 # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  22 # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  23 # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  24 # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  25 # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  26 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  27 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28 #
  29 # Authors: Nathan Binkert
  30
  31 from m5.SimObject import SimObject
  32 from m5.defines import buildEnv
  33 from m5.params import *
  34 from m5.util import fatal
  35
  36 class Root(SimObject):
  37
  38     _the_instance = None
  39
  40     def __new__(cls, **kwargs):
  41         if Root._the_instance:
  42             fatal("Attempt to allocate multiple instances of Root.")
  43             return None
  44
  45         # first call: allocate the unique instance
  46         #
  47         # If SimObject ever implements __new__, we may want to pass
  48         # kwargs here, but for now this goes straight to
  49         # object.__new__ which prints an ugly warning if you pass it
  50         # args.  Seems like a bad design but that's the way it is.
  51         Root._the_instance = SimObject.__new__(cls)
  52         return Root._the_instance
  53
  54     @classmethod
  55     def getInstance(cls):
  56         return Root._the_instance
  57
  58     def path(self):
  59         return 'root'
  60
  61     type = 'Root'
  62     cxx_header = "sim/root.hh"
  63
  64     # By default, root sim object and hence all other sim objects schedule
  65     # event on the eventq with index 0.
  66     eventq_index = 0
  67
  68     # Simulation Quantum for multiple main event queue simulation.
  69     # Needs to be set explicitly for a multi-eventq simulation.
  70     sim_quantum = Param.Tick(0, "simulation quantum")
  71
  72     full_system = Param.Bool("if this is a full system simulation")
  73
  74     # Time syncing prevents the simulation from running faster than real time.
  75     time_sync_enable = Param.Bool(False, "whether time syncing is enabled")
  76     time_sync_period = Param.Clock("100ms", "how often to sync with real time")
  77     time_sync_spin_threshold = \
  78             Param.Clock("100us", "when less than this much time is left, spin")