src/sim/ClockedObject.py

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  35
  36 from m5.SimObject import SimObject
  37 from m5.params import *
  38 from m5.proxy import *
  39
  40 # Enumerate set of allowed power states that can be used by a clocked object.
  41 # The list is kept generic to express a base minimal set.
  42 # State definition :-
  43 #   Undefined: Invalid state, no power state derived information is available.
  44 #   On: The logic block is actively running and consuming dynamic and leakage
  45 #       energy depending on the amount of processing required.
  46 #   Clk_gated: The clock circuity within the block is gated to save dynamic
  47 #              energy, the power supply to the block is still on and leakage
  48 #              energy is being consumed by the block.
  49 #   Sram_retention: The SRAMs within the logic blocks are pulled into retention
  50 #                   state to reduce leakage energy further.
  51 #   Off: The logic block is power gated and is not consuming any energy.
  52 class PwrState(Enum): vals = ['UNDEFINED',
  53                              'ON',
  54                              'CLK_GATED',
  55                              'SRAM_RETENTION',
  56                              'OFF']
  57
  58 class ClockedObject(SimObject):
  59     type = 'ClockedObject'
  60     abstract = True
  61     cxx_header = "sim/clocked_object.hh"
  62
  63     # The clock domain this clocked object belongs to, inheriting the
  64     # parent's clock domain by default
  65     clk_domain = Param.ClockDomain(Parent.clk_domain, "Clock domain")
  66
  67     # Power model for this ClockedObject
  68     power_model = VectorParam.PowerModel([], "Power models")
  69
  70     # Provide initial power state, should ideally get redefined in startup
  71     # routine
  72     default_p_state = Param.PwrState("UNDEFINED", "Default Power State")
  73
  74     p_state_clk_gate_min = Param.Latency('1ns',"Min value of the distribution")
  75     p_state_clk_gate_max = Param.Latency('1s',"Max value of the distribution")
  76     p_state_clk_gate_bins = Param.Unsigned('20',
  77         "# bins in clk gated distribution")