Ejemplo n.º 1
0
 def setUpPagewalkers(self, num, port, bypass_l1):
     if buildEnv['TARGET_ISA'] == 'arm':
         from ArmTLB import ArmTLB, ArmStage2DMMU
         self.stage2_mmu = ArmStage2DMMU(tlb=ArmTLB())
     tlbs = []
     for i in range(num):
         # set to only a single entry here so that all requests are misses
         if buildEnv['TARGET_ISA'] == 'x86':
             from X86TLB import X86TLB
             t = X86TLB(size=1)
             t.walker.bypass_l1 = bypass_l1
         elif buildEnv['TARGET_ISA'] == 'arm':
             t = ArmTLB(size=1)
             # ArmTLB does not yet include bypass_l1 option
         else:
             fatal('ShaderMMU only supports x86 and ARM architectures ' \
                   'currently')
         t.walker.port = port
         tlbs.append(t)
     self.pagewalkers = tlbs
Ejemplo n.º 2
0
class BaseCPU(MemObject):
    type = 'BaseCPU'
    abstract = True
    cxx_header = "cpu/base.hh"

    cxx_exports = [
        PyBindMethod("switchOut"),
        PyBindMethod("takeOverFrom"),
        PyBindMethod("switchedOut"),
        PyBindMethod("flushTLBs"),
        PyBindMethod("totalInsts"),
        PyBindMethod("scheduleInstStop"),
        PyBindMethod("scheduleLoadStop"),
        PyBindMethod("getCurrentInstCount"),
    ]

    @classmethod
    def memory_mode(cls):
        """Which memory mode does this CPU require?"""
        return 'invalid'

    @classmethod
    def require_caches(cls):
        """Does the CPU model require caches?

        Some CPU models might make assumptions that require them to
        have caches.
        """
        return False

    @classmethod
    def support_take_over(cls):
        """Does the CPU model support CPU takeOverFrom?"""
        return False

    def takeOverFrom(self, old_cpu):
        self._ccObject.takeOverFrom(old_cpu._ccObject)

    system = Param.System(Parent.any, "system object")
    cpu_id = Param.Int(-1, "CPU identifier")
    socket_id = Param.Unsigned(0, "Physical Socket identifier")
    numThreads = Param.Unsigned(1, "number of HW thread contexts")
    pwr_gating_latency = Param.Cycles(
        300,
        "Latency to enter power gating state when all contexts are suspended")

    power_gating_on_idle = Param.Bool(False, "Control whether the core goes "\
        "to the OFF power state after all thread are disabled for "\
        "pwr_gating_latency cycles")

    function_trace = Param.Bool(False, "Enable function trace")
    function_trace_start = Param.Tick(0, "Tick to start function trace")

    checker = Param.BaseCPU(NULL, "checker CPU")

    syscallRetryLatency = Param.Cycles(10000, "Cycles to wait until retry")

    do_checkpoint_insts = Param.Bool(True,
                                     "enable checkpoint pseudo instructions")
    do_statistics_insts = Param.Bool(True,
                                     "enable statistics pseudo instructions")

    profile = Param.Latency('0ns', "trace the kernel stack")
    do_quiesce = Param.Bool(True, "enable quiesce instructions")

    wait_for_remote_gdb = Param.Bool(False, "Wait for a remote GDB connection")

    workload = VectorParam.Process([], "processes to run")

    dtb = Param.BaseTLB(ArchDTB(), "Data TLB")
    itb = Param.BaseTLB(ArchITB(), "Instruction TLB")
    if buildEnv['TARGET_ISA'] == 'sparc':
        interrupts = VectorParam.SparcInterrupts([], "Interrupt Controller")
        isa = VectorParam.SparcISA([], "ISA instance")
    elif buildEnv['TARGET_ISA'] == 'alpha':
        interrupts = VectorParam.AlphaInterrupts([], "Interrupt Controller")
        isa = VectorParam.AlphaISA([], "ISA instance")
    elif buildEnv['TARGET_ISA'] == 'x86':
        interrupts = VectorParam.X86LocalApic([], "Interrupt Controller")
        isa = VectorParam.X86ISA([], "ISA instance")
    elif buildEnv['TARGET_ISA'] == 'mips':
        interrupts = VectorParam.MipsInterrupts([], "Interrupt Controller")
        isa = VectorParam.MipsISA([], "ISA instance")
    elif buildEnv['TARGET_ISA'] == 'arm':
        istage2_mmu = Param.ArmStage2MMU(ArmStage2IMMU(), "Stage 2 trans")
        dstage2_mmu = Param.ArmStage2MMU(ArmStage2DMMU(), "Stage 2 trans")
        interrupts = VectorParam.ArmInterrupts([], "Interrupt Controller")
        isa = VectorParam.ArmISA([], "ISA instance")
    elif buildEnv['TARGET_ISA'] == 'power':
        UnifiedTLB = Param.Bool(True, "Is this a Unified TLB?")
        interrupts = VectorParam.PowerInterrupts([], "Interrupt Controller")
        isa = VectorParam.PowerISA([], "ISA instance")
    elif buildEnv['TARGET_ISA'] == 'riscv':
        interrupts = VectorParam.RiscvInterrupts([], "Interrupt Controller")
        isa = VectorParam.RiscvISA([], "ISA instance")
    else:
        print("Don't know what TLB to use for ISA %s" % buildEnv['TARGET_ISA'])
        sys.exit(1)

    max_insts_all_threads = Param.Counter(
        0, "terminate when all threads have reached this inst count")
    max_insts_any_thread = Param.Counter(
        0, "terminate when any thread reaches this inst count")
    simpoint_start_insts = VectorParam.Counter(
        [], "starting instruction counts of simpoints")
    max_loads_all_threads = Param.Counter(
        0, "terminate when all threads have reached this load count")
    max_loads_any_thread = Param.Counter(
        0, "terminate when any thread reaches this load count")
    progress_interval = Param.Frequency(
        '0Hz', "frequency to print out the progress message")

    switched_out = Param.Bool(False,
        "Leave the CPU switched out after startup (used when switching " \
        "between CPU models)")

    tracer = Param.InstTracer(default_tracer, "Instruction tracer")

    icache_port = MasterPort("Instruction Port")
    dcache_port = MasterPort("Data Port")
    _cached_ports = ['icache_port', 'dcache_port']

    if buildEnv['TARGET_ISA'] in ['x86', 'arm']:
        _cached_ports += ["itb.walker.port", "dtb.walker.port"]

    _uncached_slave_ports = []
    _uncached_master_ports = []
    if buildEnv['TARGET_ISA'] == 'x86':
        _uncached_slave_ports += [
            "interrupts[0].pio", "interrupts[0].int_slave"
        ]
        _uncached_master_ports += ["interrupts[0].int_master"]

    def createInterruptController(self):
        if buildEnv['TARGET_ISA'] == 'sparc':
            self.interrupts = [
                SparcInterrupts() for i in xrange(self.numThreads)
            ]
        elif buildEnv['TARGET_ISA'] == 'alpha':
            self.interrupts = [
                AlphaInterrupts() for i in xrange(self.numThreads)
            ]
        elif buildEnv['TARGET_ISA'] == 'x86':
            self.apic_clk_domain = DerivedClockDomain(
                clk_domain=Parent.clk_domain, clk_divider=16)
            self.interrupts = [
                X86LocalApic(clk_domain=self.apic_clk_domain,
                             pio_addr=0x2000000000000000)
                for i in xrange(self.numThreads)
            ]
            _localApic = self.interrupts
        elif buildEnv['TARGET_ISA'] == 'mips':
            self.interrupts = [
                MipsInterrupts() for i in xrange(self.numThreads)
            ]
        elif buildEnv['TARGET_ISA'] == 'arm':
            self.interrupts = [
                ArmInterrupts() for i in xrange(self.numThreads)
            ]
        elif buildEnv['TARGET_ISA'] == 'power':
            self.interrupts = [
                PowerInterrupts() for i in xrange(self.numThreads)
            ]
        elif buildEnv['TARGET_ISA'] == 'riscv':
            self.interrupts = \
                [RiscvInterrupts() for i in xrange(self.numThreads)]
        else:
            print("Don't know what Interrupt Controller to use for ISA %s" %
                  buildEnv['TARGET_ISA'])
            sys.exit(1)

    def connectCachedPorts(self, bus):
        for p in self._cached_ports:
            exec('self.%s = bus.slave' % p)

    def connectUncachedPorts(self, bus):
        for p in self._uncached_slave_ports:
            exec('self.%s = bus.master' % p)
        for p in self._uncached_master_ports:
            exec('self.%s = bus.slave' % p)

    def connectAllPorts(self, cached_bus, uncached_bus=None):
        self.connectCachedPorts(cached_bus)
        if not uncached_bus:
            uncached_bus = cached_bus
        self.connectUncachedPorts(uncached_bus)

    def addPrivateSplitL1Caches(self, ic, dc, iwc=None, dwc=None):
        self.icache = ic
        self.dcache = dc
        self.icache_port = ic.cpu_side
        self.dcache_port = dc.cpu_side
        self._cached_ports = ['icache.mem_side', 'dcache.mem_side']
        if buildEnv['TARGET_ISA'] in ['x86', 'arm']:
            if iwc and dwc:
                self.itb_walker_cache = iwc
                self.dtb_walker_cache = dwc
                self.itb.walker.port = iwc.cpu_side
                self.dtb.walker.port = dwc.cpu_side
                self._cached_ports += ["itb_walker_cache.mem_side", \
                                       "dtb_walker_cache.mem_side"]
            else:
                self._cached_ports += ["itb.walker.port", "dtb.walker.port"]

            # Checker doesn't need its own tlb caches because it does
            # functional accesses only
            if self.checker != NULL:
                self._cached_ports += ["checker.itb.walker.port", \
                                       "checker.dtb.walker.port"]

    def addTwoLevelCacheHierarchy(self,
                                  ic,
                                  dc,
                                  l2c,
                                  iwc=None,
                                  dwc=None,
                                  xbar=None):
        self.addPrivateSplitL1Caches(ic, dc, iwc, dwc)
        self.toL2Bus = xbar if xbar else L2XBar()
        self.connectCachedPorts(self.toL2Bus)
        self.l2cache = l2c
        self.toL2Bus.master = self.l2cache.cpu_side
        self._cached_ports = ['l2cache.mem_side']

    def createThreads(self):
        # If no ISAs have been created, assume that the user wants the
        # default ISA.
        if len(self.isa) == 0:
            self.isa = [default_isa_class() for i in xrange(self.numThreads)]
        else:
            if len(self.isa) != int(self.numThreads):
                raise RuntimeError("Number of ISA instances doesn't "
                                   "match thread count")
        if self.checker != NULL:
            self.checker.createThreads()

    def addCheckerCpu(self):
        pass

    def createPhandleKey(self, thread):
        # This method creates a unique key for this cpu as a function of a
        # certain thread
        return 'CPU-%d-%d-%d' % (self.socket_id, self.cpu_id, thread)

    #Generate simple CPU Device Tree structure
    def generateDeviceTree(self, state):
        """Generate cpu nodes for each thread and the corresponding part of the
        cpu-map node. Note that this implementation does not support clusters
        of clusters. Note that GEM5 is not compatible with the official way of
        numbering cores as defined in the Device Tree documentation. Where the
        cpu_id needs to reset to 0 for each cluster by specification, GEM5
        expects the cpu_id to be globally unique and incremental. This
        generated node adheres the GEM5 way of doing things."""
        if bool(self.switched_out):
            return

        cpus_node = FdtNode('cpus')
        cpus_node.append(state.CPUCellsProperty())
        #Special size override of 0
        cpus_node.append(FdtPropertyWords('#size-cells', [0]))

        # Generate cpu nodes
        for i in range(int(self.numThreads)):
            reg = (int(self.socket_id) << 8) + int(self.cpu_id) + i
            node = FdtNode("cpu@%x" % reg)
            node.append(FdtPropertyStrings("device_type", "cpu"))
            node.appendCompatible(["gem5,arm-cpu"])
            node.append(FdtPropertyWords("reg", state.CPUAddrCells(reg)))
            platform, found = self.system.unproxy(self).find_any(Platform)
            if found:
                platform.annotateCpuDeviceNode(node, state)
            else:
                warn("Platform not found for device tree generation; " \
                     "system or multiple CPUs may not start")

            freq = round(self.clk_domain.unproxy(self).clock[0].frequency)
            node.append(FdtPropertyWords("clock-frequency", freq))

            # Unique key for this CPU
            phandle_key = self.createPhandleKey(i)
            node.appendPhandle(phandle_key)
            cpus_node.append(node)

        yield cpus_node
Ejemplo n.º 3
0
class BaseCPU(MemObject):
    type = 'BaseCPU'
    abstract = True
    cxx_header = "cpu/base.hh"

    @classmethod
    def export_methods(cls, code):
        code('''
    void switchOut();
    void takeOverFrom(BaseCPU *cpu);
    bool switchedOut();
    void flushTLBs();
    Counter totalInsts();
    void scheduleInstStop(ThreadID tid, Counter insts, const char *cause);
    void scheduleLoadStop(ThreadID tid, Counter loads, const char *cause);
''')

    @classmethod
    def memory_mode(cls):
        """Which memory mode does this CPU require?"""
        return 'invalid'

    @classmethod
    def require_caches(cls):
        """Does the CPU model require caches?

        Some CPU models might make assumptions that require them to
        have caches.
        """
        return False

    @classmethod
    def support_take_over(cls):
        """Does the CPU model support CPU takeOverFrom?"""
        return False

    def takeOverFrom(self, old_cpu):
        self._ccObject.takeOverFrom(old_cpu._ccObject)

    system = Param.System(Parent.any, "system object")
    cpu_id = Param.Int(-1, "CPU identifier")
    socket_id = Param.Unsigned(0, "Physical Socket identifier")
    numThreads = Param.Unsigned(1, "number of HW thread contexts")

    function_trace = Param.Bool(False, "Enable function trace")
    function_trace_start = Param.Tick(0, "Tick to start function trace")

    checker = Param.BaseCPU(NULL, "checker CPU")

    do_checkpoint_insts = Param.Bool(True,
                                     "enable checkpoint pseudo instructions")
    do_statistics_insts = Param.Bool(True,
                                     "enable statistics pseudo instructions")

    profile = Param.Latency('0ns', "trace the kernel stack")
    do_quiesce = Param.Bool(True, "enable quiesce instructions")

    workload = VectorParam.Process([], "processes to run")

    if buildEnv['TARGET_ISA'] == 'sparc':
        dtb = Param.SparcTLB(SparcTLB(), "Data TLB")
        itb = Param.SparcTLB(SparcTLB(), "Instruction TLB")
        interrupts = Param.SparcInterrupts(NULL, "Interrupt Controller")
        isa = VectorParam.SparcISA([isa_class()], "ISA instance")
    elif buildEnv['TARGET_ISA'] == 'alpha':
        dtb = Param.AlphaTLB(AlphaDTB(), "Data TLB")
        itb = Param.AlphaTLB(AlphaITB(), "Instruction TLB")
        interrupts = Param.AlphaInterrupts(NULL, "Interrupt Controller")
        isa = VectorParam.AlphaISA([isa_class()], "ISA instance")
    elif buildEnv['TARGET_ISA'] == 'x86':
        dtb = Param.X86TLB(X86TLB(), "Data TLB")
        itb = Param.X86TLB(X86TLB(), "Instruction TLB")
        interrupts = Param.X86LocalApic(NULL, "Interrupt Controller")
        isa = VectorParam.X86ISA([isa_class()], "ISA instance")
    elif buildEnv['TARGET_ISA'] == 'mips':
        dtb = Param.MipsTLB(MipsTLB(), "Data TLB")
        itb = Param.MipsTLB(MipsTLB(), "Instruction TLB")
        interrupts = Param.MipsInterrupts(NULL, "Interrupt Controller")
        isa = VectorParam.MipsISA([isa_class()], "ISA instance")
    elif buildEnv['TARGET_ISA'] == 'arm':
        dtb = Param.ArmTLB(ArmTLB(), "Data TLB")
        itb = Param.ArmTLB(ArmTLB(), "Instruction TLB")
        istage2_mmu = Param.ArmStage2MMU(ArmStage2IMMU(), "Stage 2 trans")
        dstage2_mmu = Param.ArmStage2MMU(ArmStage2DMMU(), "Stage 2 trans")
        interrupts = Param.ArmInterrupts(NULL, "Interrupt Controller")
        isa = VectorParam.ArmISA([isa_class()], "ISA instance")
    elif buildEnv['TARGET_ISA'] == 'power':
        UnifiedTLB = Param.Bool(True, "Is this a Unified TLB?")
        dtb = Param.PowerTLB(PowerTLB(), "Data TLB")
        itb = Param.PowerTLB(PowerTLB(), "Instruction TLB")
        interrupts = Param.PowerInterrupts(NULL, "Interrupt Controller")
        isa = VectorParam.PowerISA([isa_class()], "ISA instance")
    else:
        print "Don't know what TLB to use for ISA %s" % \
            buildEnv['TARGET_ISA']
        sys.exit(1)

    max_insts_all_threads = Param.Counter(
        0, "terminate when all threads have reached this inst count")
    max_insts_any_thread = Param.Counter(
        0, "terminate when any thread reaches this inst count")
    simpoint_start_insts = VectorParam.Counter(
        [], "starting instruction counts of simpoints")
    max_loads_all_threads = Param.Counter(
        0, "terminate when all threads have reached this load count")
    max_loads_any_thread = Param.Counter(
        0, "terminate when any thread reaches this load count")
    progress_interval = Param.Frequency(
        '0Hz', "frequency to print out the progress message")

    switched_out = Param.Bool(False,
        "Leave the CPU switched out after startup (used when switching " \
        "between CPU models)")

    tracer = Param.InstTracer(default_tracer, "Instruction tracer")

    icache_port = MasterPort("Instruction Port")
    dcache_port = MasterPort("Data Port")
    _cached_ports = ['icache_port', 'dcache_port']

    if buildEnv['TARGET_ISA'] in ['x86', 'arm']:
        _cached_ports += ["itb.walker.port", "dtb.walker.port"]

    _uncached_slave_ports = []
    _uncached_master_ports = []
    if buildEnv['TARGET_ISA'] == 'x86':
        _uncached_slave_ports += ["interrupts.pio", "interrupts.int_slave"]
        _uncached_master_ports += ["interrupts.int_master"]

    def createInterruptController(self):
        if buildEnv['TARGET_ISA'] == 'sparc':
            self.interrupts = SparcInterrupts()
        elif buildEnv['TARGET_ISA'] == 'alpha':
            self.interrupts = AlphaInterrupts()
        elif buildEnv['TARGET_ISA'] == 'x86':
            self.apic_clk_domain = DerivedClockDomain(
                clk_domain=Parent.clk_domain, clk_divider=16)
            self.interrupts = X86LocalApic(clk_domain=self.apic_clk_domain,
                                           pio_addr=0x2000000000000000)
            _localApic = self.interrupts
        elif buildEnv['TARGET_ISA'] == 'mips':
            self.interrupts = MipsInterrupts()
        elif buildEnv['TARGET_ISA'] == 'arm':
            self.interrupts = ArmInterrupts()
        elif buildEnv['TARGET_ISA'] == 'power':
            self.interrupts = PowerInterrupts()
        else:
            print "Don't know what Interrupt Controller to use for ISA %s" % \
                buildEnv['TARGET_ISA']
            sys.exit(1)

    def connectCachedPorts(self, bus):
        for p in self._cached_ports:
            exec('self.%s = bus.slave' % p)

    def connectUncachedPorts(self, bus):
        for p in self._uncached_slave_ports:
            exec('self.%s = bus.master' % p)
        for p in self._uncached_master_ports:
            exec('self.%s = bus.slave' % p)

    def connectAllPorts(self, cached_bus, uncached_bus=None):
        self.connectCachedPorts(cached_bus)
        if not uncached_bus:
            uncached_bus = cached_bus
        self.connectUncachedPorts(uncached_bus)

    def addPrivateSplitL1Caches(self, ic, dc, iwc=None, dwc=None):
        self.icache = ic
        self.dcache = dc
        self.icache_port = ic.cpu_side
        self.dcache_port = dc.cpu_side
        self._cached_ports = ['icache.mem_side', 'dcache.mem_side']
        # AK: Add nvwrite side to icache and dcache
        self._uncached_master_ports = [
            'icache.nvwrite_side', 'dcache.nvwrite_side'
        ]
        if buildEnv['TARGET_ISA'] in ['x86', 'arm']:
            if iwc and dwc:
                self.itb_walker_cache = iwc
                self.dtb_walker_cache = dwc
                self.itb.walker.port = iwc.cpu_side
                self.dtb.walker.port = dwc.cpu_side
                self._cached_ports += ["itb_walker_cache.mem_side", \
                                       "dtb_walker_cache.mem_side"]
            else:
                self._cached_ports += ["itb.walker.port", "dtb.walker.port"]

            # Checker doesn't need its own tlb caches because it does
            # functional accesses only
            if self.checker != NULL:
                self._cached_ports += ["checker.itb.walker.port", \
                                       "checker.dtb.walker.port"]

    def addTwoLevelCacheHierarchy(self, ic, dc, l2c, iwc=None, dwc=None):
        self.addPrivateSplitL1Caches(ic, dc, iwc, dwc)
        self.toL2Bus = L2XBar()
        self.connectCachedPorts(self.toL2Bus)
        self.l2cache = l2c
        self.toL2Bus.master = self.l2cache.cpu_side
        self._cached_ports = ['l2cache.mem_side']

    def createThreads(self):
        self.isa = [isa_class() for i in xrange(self.numThreads)]
        if self.checker != NULL:
            self.checker.createThreads()

    def addCheckerCpu(self):
        pass
Ejemplo n.º 4
0
class BaseCPU(MemObject):
    type = 'BaseCPU'
    abstract = True
    cxx_header = "cpu/base.hh"

    cxx_exports = [
        PyBindMethod("switchOut"),
        PyBindMethod("takeOverFrom"),
        PyBindMethod("switchedOut"),
        PyBindMethod("flushTLBs"),
        PyBindMethod("totalInsts"),
        PyBindMethod("scheduleInstStop"),
        PyBindMethod("scheduleLoadStop"),
        PyBindMethod("getCurrentInstCount"),
    ]

    @classmethod
    def memory_mode(cls):
        """Which memory mode does this CPU require?"""
        return 'invalid'

    @classmethod
    def require_caches(cls):
        """Does the CPU model require caches?

        Some CPU models might make assumptions that require them to
        have caches.
        """
        return False

    @classmethod
    def support_take_over(cls):
        """Does the CPU model support CPU takeOverFrom?"""
        return False

    def takeOverFrom(self, old_cpu):
        self._ccObject.takeOverFrom(old_cpu._ccObject)

    system = Param.System(Parent.any, "system object")
    cpu_id = Param.Int(-1, "CPU identifier")
    socket_id = Param.Unsigned(0, "Physical Socket identifier")
    numThreads = Param.Unsigned(1, "number of HW thread contexts")
    pwr_gating_latency = Param.Cycles(
        300,
        "Latency to enter power gating state when all contexts are suspended")

    power_gating_on_idle = Param.Bool(False, "Control whether the core goes "\
        "to the OFF power state after all thread are disabled for "\
        "pwr_gating_latency cycles")

    function_trace = Param.Bool(False, "Enable function trace")
    function_trace_start = Param.Tick(0, "Tick to start function trace")

    checker = Param.BaseCPU(NULL, "checker CPU")

    syscallRetryLatency = Param.Cycles(10000, "Cycles to wait until retry")

    do_checkpoint_insts = Param.Bool(True,
                                     "enable checkpoint pseudo instructions")
    do_statistics_insts = Param.Bool(True,
                                     "enable statistics pseudo instructions")

    profile = Param.Latency('0ns', "trace the kernel stack")
    do_quiesce = Param.Bool(True, "enable quiesce instructions")

    wait_for_remote_gdb = Param.Bool(False, "Wait for a remote GDB connection")

    workload = VectorParam.Process([], "processes to run")

    if buildEnv['TARGET_ISA'] == 'sparc':
        dtb = Param.SparcTLB(SparcTLB(), "Data TLB")
        itb = Param.SparcTLB(SparcTLB(), "Instruction TLB")
        interrupts = VectorParam.SparcInterrupts([], "Interrupt Controller")
        isa = VectorParam.SparcISA([], "ISA instance")
    elif buildEnv['TARGET_ISA'] == 'alpha':
        dtb = Param.AlphaTLB(AlphaDTB(), "Data TLB")
        itb = Param.AlphaTLB(AlphaITB(), "Instruction TLB")
        interrupts = VectorParam.AlphaInterrupts([], "Interrupt Controller")
        isa = VectorParam.AlphaISA([], "ISA instance")
    elif buildEnv['TARGET_ISA'] == 'x86':
        dtb = Param.X86TLB(X86TLB(), "Data TLB")
        itb = Param.X86TLB(X86TLB(), "Instruction TLB")
        interrupts = VectorParam.X86LocalApic([], "Interrupt Controller")
        isa = VectorParam.X86ISA([], "ISA instance")
    elif buildEnv['TARGET_ISA'] == 'mips':
        dtb = Param.MipsTLB(MipsTLB(), "Data TLB")
        itb = Param.MipsTLB(MipsTLB(), "Instruction TLB")
        interrupts = VectorParam.MipsInterrupts([], "Interrupt Controller")
        isa = VectorParam.MipsISA([], "ISA instance")
    elif buildEnv['TARGET_ISA'] == 'arm':
        dtb = Param.ArmTLB(ArmTLB(), "Data TLB")
        itb = Param.ArmTLB(ArmTLB(), "Instruction TLB")
        istage2_mmu = Param.ArmStage2MMU(ArmStage2IMMU(), "Stage 2 trans")
        dstage2_mmu = Param.ArmStage2MMU(ArmStage2DMMU(), "Stage 2 trans")
        interrupts = VectorParam.ArmInterrupts([], "Interrupt Controller")
        isa = VectorParam.ArmISA([], "ISA instance")
    elif buildEnv['TARGET_ISA'] == 'power':
        UnifiedTLB = Param.Bool(True, "Is this a Unified TLB?")
        dtb = Param.PowerTLB(PowerTLB(), "Data TLB")
        itb = Param.PowerTLB(PowerTLB(), "Instruction TLB")
        interrupts = VectorParam.PowerInterrupts([], "Interrupt Controller")
        isa = VectorParam.PowerISA([], "ISA instance")
    elif buildEnv['TARGET_ISA'] == 'riscv':
        dtb = Param.RiscvTLB(RiscvTLB(), "Data TLB")
        itb = Param.RiscvTLB(RiscvTLB(), "Instruction TLB")
        interrupts = VectorParam.RiscvInterrupts([], "Interrupt Controller")
        isa = VectorParam.RiscvISA([], "ISA instance")
    else:
        print "Don't know what TLB to use for ISA %s" % \
            buildEnv['TARGET_ISA']
        sys.exit(1)

    max_insts_all_threads = Param.Counter(
        0, "terminate when all threads have reached this inst count")
    max_insts_any_thread = Param.Counter(
        0, "terminate when any thread reaches this inst count")
    simpoint_start_insts = VectorParam.Counter(
        [], "starting instruction counts of simpoints")
    max_loads_all_threads = Param.Counter(
        0, "terminate when all threads have reached this load count")
    max_loads_any_thread = Param.Counter(
        0, "terminate when any thread reaches this load count")
    progress_interval = Param.Frequency(
        '0Hz', "frequency to print out the progress message")

    switched_out = Param.Bool(False,
        "Leave the CPU switched out after startup (used when switching " \
        "between CPU models)")

    tracer = Param.InstTracer(default_tracer, "Instruction tracer")

    icache_port = MasterPort("Instruction Port")
    dcache_port = MasterPort("Data Port")
    _cached_ports = ['icache_port', 'dcache_port']

    if buildEnv['TARGET_ISA'] in ['x86', 'arm']:
        _cached_ports += ["itb.walker.port", "dtb.walker.port"]

    _uncached_slave_ports = []
    _uncached_master_ports = []
    if buildEnv['TARGET_ISA'] == 'x86':
        _uncached_slave_ports += [
            "interrupts[0].pio", "interrupts[0].int_slave"
        ]
        _uncached_master_ports += ["interrupts[0].int_master"]

    def createInterruptController(self):
        if buildEnv['TARGET_ISA'] == 'sparc':
            self.interrupts = [
                SparcInterrupts() for i in xrange(self.numThreads)
            ]
        elif buildEnv['TARGET_ISA'] == 'alpha':
            self.interrupts = [
                AlphaInterrupts() for i in xrange(self.numThreads)
            ]
        elif buildEnv['TARGET_ISA'] == 'x86':
            self.apic_clk_domain = DerivedClockDomain(
                clk_domain=Parent.clk_domain, clk_divider=16)
            self.interrupts = [
                X86LocalApic(clk_domain=self.apic_clk_domain,
                             pio_addr=0x2000000000000000)
                for i in xrange(self.numThreads)
            ]
            _localApic = self.interrupts
        elif buildEnv['TARGET_ISA'] == 'mips':
            self.interrupts = [
                MipsInterrupts() for i in xrange(self.numThreads)
            ]
        elif buildEnv['TARGET_ISA'] == 'arm':
            self.interrupts = [
                ArmInterrupts() for i in xrange(self.numThreads)
            ]
        elif buildEnv['TARGET_ISA'] == 'power':
            self.interrupts = [
                PowerInterrupts() for i in xrange(self.numThreads)
            ]
        elif buildEnv['TARGET_ISA'] == 'riscv':
            self.interrupts = \
                [RiscvInterrupts() for i in xrange(self.numThreads)]
        else:
            print "Don't know what Interrupt Controller to use for ISA %s" % \
                buildEnv['TARGET_ISA']
            sys.exit(1)

    def connectCachedPorts(self, bus):
        for p in self._cached_ports:
            exec('self.%s = bus.slave' % p)

    def connectUncachedPorts(self, bus):
        for p in self._uncached_slave_ports:
            exec('self.%s = bus.master' % p)
        for p in self._uncached_master_ports:
            exec('self.%s = bus.slave' % p)

    def connectAllPorts(self, cached_bus, uncached_bus=None):
        self.connectCachedPorts(cached_bus)
        if not uncached_bus:
            uncached_bus = cached_bus
        self.connectUncachedPorts(uncached_bus)

    def addPrivateSplitL1Caches(self, ic, dc, iwc=None, dwc=None, dspm=None):
        if dspm:
            self.icache = ic
            self.icache_port = ic.cpu_side
            self.dspm = dspm
            self.dcache_port = dspm.cpu_side  #weird but correct!
            if dc:
                self.dcache = dc
                self.dspm.mem_side = self.dcache.cpu_side
                self._cached_ports = ['icache.mem_side', 'dcache.mem_side']
            else:
                self._cached_ports = ['icache.mem_side', 'dspm.mem_side']
        else:
            self.icache = ic
            self.dcache = dc
            self.icache_port = ic.cpu_side
            self.dcache_port = dc.cpu_side
            self._cached_ports = ['icache.mem_side', 'dcache.mem_side']
        if buildEnv['TARGET_ISA'] in ['x86', 'arm']:
            if iwc and dwc:
                self.itb_walker_cache = iwc
                self.dtb_walker_cache = dwc
                self.itb.walker.port = iwc.cpu_side
                self.dtb.walker.port = dwc.cpu_side
                self._cached_ports += ["itb_walker_cache.mem_side", \
                                       "dtb_walker_cache.mem_side"]
            else:
                self._cached_ports += ["itb.walker.port", "dtb.walker.port"]

            # Checker doesn't need its own tlb caches because it does
            # functional accesses only
            if self.checker != NULL:
                self._cached_ports += ["checker.itb.walker.port", \
                                       "checker.dtb.walker.port"]

    def addTwoLevelCacheHierarchy(self, ic, dc, l2c, iwc=None, dwc=None):
        self.addPrivateSplitL1Caches(ic, dc, iwc, dwc)
        self.toL2Bus = L2XBar()
        self.connectCachedPorts(self.toL2Bus)
        self.l2cache = l2c
        self.toL2Bus.master = self.l2cache.cpu_side
        self._cached_ports = ['l2cache.mem_side']

    def createThreads(self):
        # If no ISAs have been created, assume that the user wants the
        # default ISA.
        if len(self.isa) == 0:
            self.isa = [default_isa_class() for i in xrange(self.numThreads)]
        else:
            if len(self.isa) != int(self.numThreads):
                raise RuntimeError("Number of ISA instances doesn't "
                                   "match thread count")
        if self.checker != NULL:
            self.checker.createThreads()

    def addCheckerCpu(self):
        pass