src/sim/ClockedObject.py

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  36 # Authors: Andreas Hansson
  37
  38 from m5.SimObject import SimObject
  39 from m5.params import *
  40 from m5.proxy import *
  41
  42 # Enumerate set of allowed power states that can be used by a clocked object.
  43 # The list is kept generic to express a base minimal set.
  44 # State definition :-
  45 #   Undefined: Invalid state, no power state derived information is available.
  46 #   On: The logic block is actively running and consuming dynamic and leakage
  47 #       energy depending on the amount of processing required.
  48 #   Clk_gated: The clock circuity within the block is gated to save dynamic
  49 #              energy, the power supply to the block is still on and leakage
  50 #              energy is being consumed by the block.
  51 #   Sram_retention: The SRAMs within the logic blocks are pulled into retention
  52 #                   state to reduce leakage energy further.
  53 #   Off: The logic block is power gated and is not consuming any energy.
  54 class PwrState(Enum): vals = ['UNDEFINED',
  55                              'ON',
  56                              'CLK_GATED',
  57                              'SRAM_RETENTION',
  58                              'OFF']
  59
  60 class ClockedObject(SimObject):
  61     type = 'ClockedObject'
  62     abstract = True
  63     cxx_header = "sim/clocked_object.hh"
  64
  65     # The clock domain this clocked object belongs to, inheriting the
  66     # parent's clock domain by default
  67     clk_domain = Param.ClockDomain(Parent.clk_domain, "Clock domain")
  68
  69     # Power model for this ClockedObject
  70     power_model = VectorParam.PowerModel([], "Power models")
  71
  72     # Provide initial power state, should ideally get redefined in startup
  73     # routine
  74     default_p_state = Param.PwrState("UNDEFINED", "Default Power State")
  75
  76     p_state_clk_gate_min = Param.Latency('1ns',"Min value of the distribution")
  77     p_state_clk_gate_max = Param.Latency('1s',"Max value of the distribution")
  78     p_state_clk_gate_bins = Param.Unsigned('20',
  79         "# bins in clk gated distribution")