Root.py revision 7861:4ebff121cc0e 
1# Copyright (c) 2005-2007 The Regents of The University of Michigan
2# Copyright (c) 2010 Advanced Micro Devices, Inc.
3# All rights reserved.
4#
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14# this software without specific prior written permission.
15#
16# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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27#
28# Authors: Nathan Binkert
29
30from m5.SimObject import SimObject
31from m5.params import *
32from m5.util import fatal
33
34class Root(SimObject):
35
36    _the_instance = None
37
38    def __new__(cls, **kwargs):
39        if Root._the_instance:
40            fatal("Attempt to allocate multiple instances of Root.")
41            return None
42
43        # first call: allocate the unique instance
44        #
45        # If SimObject ever implements __new__, we may want to pass
46        # kwargs here, but for now this goes straight to
47        # object.__new__ which prints an ugly warning if you pass it
48        # args.  Seems like a bad design but that's the way it is.
49        Root._the_instance = SimObject.__new__(cls)
50        return Root._the_instance
51
52    @classmethod
53    def getInstance(cls):
54        return Root._the_instance
55
56    def path(self):
57        return 'root'
58
59    type = 'Root'
60
61    # Time syncing prevents the simulation from running faster than real time.
62    time_sync_enable = Param.Bool(False, "whether time syncing is enabled")
63    time_sync_period = Param.Clock("100ms", "how often to sync with real time")
64    time_sync_spin_threshold = \
65            Param.Clock("100us", "when less than this much time is left, spin")
66