xref: /gem5/src/sim/ClockedObject.py

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# Authors: Andreas Hansson

from m5.SimObject import SimObject
from m5.params import *
from m5.proxy import *

# Enumerate set of allowed power states that can be used by a clocked object.
# The list is kept generic to express a base minimal set.
# State definition :-
#   Undefined: Invalid state, no power state derived information is available.
#   On: The logic block is actively running and consuming dynamic and leakage
#       energy depending on the amount of processing required.
#   Clk_gated: The clock circuity within the block is gated to save dynamic
#              energy, the power supply to the block is still on and leakage
#              energy is being consumed by the block.
#   Sram_retention: The SRAMs within the logic blocks are pulled into retention
#                   state to reduce leakage energy further.
#   Off: The logic block is power gated and is not consuming any energy.
class PwrState(Enum): vals = ['UNDEFINED',
                             'ON',
                             'CLK_GATED',
                             'SRAM_RETENTION',
                             'OFF']

class ClockedObject(SimObject):
    type = 'ClockedObject'
    abstract = True
    cxx_header = "sim/clocked_object.hh"

    # The clock domain this clocked object belongs to, inheriting the
    # parent's clock domain by default
    clk_domain = Param.ClockDomain(Parent.clk_domain, "Clock domain")

    # Power model for this ClockedObject
    power_model = Param.PowerModel(NULL, "Power model")

    # Provide initial power state, should ideally get redefined in startup
    # routine
    default_p_state = Param.PwrState("UNDEFINED", "Default Power State")

    p_state_clk_gate_min = Param.Latency('1ns',"Min value of the distribution")
    p_state_clk_gate_max = Param.Latency('1s',"Max value of the distribution")
    p_state_clk_gate_bins = Param.Unsigned('20',
        "# bins in clk gated distribution")