Root.py revision 7525 
1# Copyright (c) 2005-2007 The Regents of The University of Michigan
2# All rights reserved.
3#
4# Redistribution and use in source and binary forms, with or without
5# modification, are permitted provided that the following conditions are
6# met: redistributions of source code must retain the above copyright
7# notice, this list of conditions and the following disclaimer;
8# redistributions in binary form must reproduce the above copyright
9# notice, this list of conditions and the following disclaimer in the
10# documentation and/or other materials provided with the distribution;
11# neither the name of the copyright holders nor the names of its
12# contributors may be used to endorse or promote products derived from
13# this software without specific prior written permission.
14#
15# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
18# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
19# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
20# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
21# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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25# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26#
27# Authors: Nathan Binkert
28
29from m5.SimObject import SimObject
30from m5.params import *
31from m5.util import fatal
32
33class Root(SimObject):
34
35    _the_instance = None
36
37    def __new__(cls, **kwargs):
38        if Root._the_instance:
39            fatal("Attempt to allocate multiple instances of Root.")
40            return None
41
42        # first call: allocate the unique instance
43        #
44        # If SimObject ever implements __new__, we may want to pass
45        # kwargs here, but for now this goes straight to
46        # object.__new__ which prints an ugly warning if you pass it
47        # args.  Seems like a bad design but that's the way it is.
48        Root._the_instance = SimObject.__new__(cls)
49        return Root._the_instance
50
51    @classmethod
52    def getInstance(cls):
53        return Root._the_instance
54
55    def path(self):
56        return 'root'
57
58    type = 'Root'
59    dummy = Param.Int(0, "We don't support objects without params")
60