src/sim/PowerState.py

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  36
  37 from m5.SimObject import SimObject
  38 from m5.params import *
  39 from m5.proxy import *
  40
  41 # Enumerate set of allowed power states that can be used by a clocked object.
  42 # The list is kept generic to express a base minimal set.
  43 # State definition :-
  44 #   Undefined: Invalid state, no power state derived information is available.
  45 #   On: The logic block is actively running and consuming dynamic and leakage
  46 #       energy depending on the amount of processing required.
  47 #   Clk_gated: The clock circuity within the block is gated to save dynamic
  48 #              energy, the power supply to the block is still on and leakage
  49 #              energy is being consumed by the block.
  50 #   Sram_retention: The SRAMs within the logic blocks are pulled into retention
  51 #                   state to reduce leakage energy further.
  52 #   Off: The logic block is power gated and is not consuming any energy.
  53 class PwrState(Enum): vals = [
  54         'UNDEFINED', 'ON', 'CLK_GATED', 'SRAM_RETENTION', 'OFF'
  55 ]
  56
  57 class PowerState(SimObject):
  58     type = 'PowerState'
  59     cxx_header = "sim/power_state.hh"
  60
  61     # Provide initial power state, should ideally get redefined in startup
  62     # routine
  63     default_state = Param.PwrState("UNDEFINED", "Default Power State")
  64
  65     # Possible power states this object can be in sorted from the most
  66     # to the least performant
  67     possible_states = VectorParam.PwrState(
  68         [], "Power states this object can be in")
  69
  70     clk_gate_min = Param.Latency('1ns',"Min value of the distribution")
  71     clk_gate_max = Param.Latency('1s',"Max value of the distribution")
  72     clk_gate_bins = Param.Unsigned('20', "# bins in clk gated distribution")
  73
  74     # The objects which drive the power state of this object. If the list is
  75     # empty, the object determines its power state independently.
  76     leaders = VectorParam.PowerState(
  77         [], "Objects which drive the power state of this object")