src/mem/XBar.py

   1 # Copyright (c) 2012 ARM Limited
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  13 # Copyright (c) 2005-2008 The Regents of The University of Michigan
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  38 #
  39 # Authors: Nathan Binkert
  40 #          Andreas Hansson
  41
  42 from MemObject import MemObject
  43 from System import System
  44 from m5.params import *
  45 from m5.proxy import *
  46 from m5.SimObject import SimObject
  47
  48 class BaseXBar(MemObject):
  49     type = 'BaseXBar'
  50     abstract = True
  51     cxx_header = "mem/xbar.hh"
  52     slave = VectorSlavePort("vector port for connecting masters")
  53     master = VectorMasterPort("vector port for connecting slaves")
  54     header_cycles = Param.Cycles(1, "cycles of overhead per transaction")
  55     width = Param.Unsigned(8, "xbar width (bytes)")
  56
  57     # The default port can be left unconnected, or be used to connect
  58     # a default slave port
  59     default = MasterPort("Port for connecting an optional default slave")
  60
  61     # The default port can be used unconditionally, or based on
  62     # address range, in which case it may overlap with other
  63     # ports. The default range is always checked first, thus creating
  64     # a two-level hierarchical lookup. This is useful e.g. for the PCI
  65     # xbar configuration.
  66     use_default_range = Param.Bool(False, "Perform address mapping for " \
  67                                        "the default port")
  68
  69 class NoncoherentXBar(BaseXBar):
  70     type = 'NoncoherentXBar'
  71     cxx_header = "mem/noncoherent_xbar.hh"
  72
  73 class CoherentXBar(BaseXBar):
  74     type = 'CoherentXBar'
  75     cxx_header = "mem/coherent_xbar.hh"
  76
  77     system = Param.System(Parent.any, "System that the crossbar belongs to.")
  78     snoop_filter = Param.SnoopFilter(NULL, "Selected snoop filter.")
  79
  80 class SnoopFilter(SimObject):
  81     type = 'SnoopFilter'
  82     cxx_header = "mem/snoop_filter.hh"
  83     lookup_latency = Param.Cycles(3, "lookup latency (cycles)")
  84
  85     system = Param.System(Parent.any, "System that the crossbar belongs to.")