xref: /gem5/src/sim/Root.py

# Copyright (c) 2005-2007 The Regents of The University of Michigan
# Copyright (c) 2010 Advanced Micro Devices, Inc.
# All rights reserved.
#
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# redistributions in binary form must reproduce the above copyright
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# documentation and/or other materials provided with the distribution;
# neither the name of the copyright holders nor the names of its
# contributors may be used to endorse or promote products derived from
# this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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# Authors: Nathan Binkert

from m5.SimObject import SimObject
from m5.params import *
from m5.util import fatal

class Root(SimObject):

    _the_instance = None

    def __new__(cls, **kwargs):
        if Root._the_instance:
            fatal("Attempt to allocate multiple instances of Root.")
            return None

        # first call: allocate the unique instance
        #
        # If SimObject ever implements __new__, we may want to pass
        # kwargs here, but for now this goes straight to
        # object.__new__ which prints an ugly warning if you pass it
        # args.  Seems like a bad design but that's the way it is.
        Root._the_instance = SimObject.__new__(cls)
        return Root._the_instance

    @classmethod
    def getInstance(cls):
        return Root._the_instance

    def path(self):
        return 'root'

    type = 'Root'
    dummy = Param.Int(0, "We don't support objects without params")