# Copyright (c) 2021 The Regents of the University of California
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from .abstract_node import AbstractNode

from m5.objects import (
    ClockDomain,
    NULL,
    RubyCache,
    RubyNetwork,
)

class SimpleDirectory(AbstractNode):
    """A directory or home node (HNF)

    This simple directory has no cache. It forwards all requests as directly
    as possible.
    """
    def __init__(
        self,
        network: RubyNetwork,
        cache_line_size: int,
        clk_domain: ClockDomain,
    ):
        super().__init__(network, cache_line_size)

        # Dummy cache
        self.cache = RubyCache(
            dataAccessLatency = 0,
            tagAccessLatency = 1,
            size = "128",
            assoc = 1
        )

        self.clk_domain = clk_domain

        # Only used for L1 controllers
        self.send_evictions = False
        self.sequencer = NULL

        self.use_prefetcher = False

        # Set up home node that allows three hop protocols
        self.is_HN = True
        self.enable_DMT = True
        self.enable_DCT = True

        # "Owned state"
        self.allow_SD = True

        # No cache
        self.alloc_on_seq_acc = False
        self.alloc_on_seq_line_write = False
        self.alloc_on_readshared = False
        self.alloc_on_readunique = False
        self.alloc_on_readonce = False
        self.alloc_on_writeback = False
        self.dealloc_on_unique = False
        self.dealloc_on_shared = False
        self.dealloc_backinv_unique = False
        self.dealloc_backinv_shared = False

        # Some reasonable default TBE params
        self.number_of_TBEs = 32
        self.number_of_repl_TBEs = 32
        self.number_of_snoop_TBEs = 1
        self.unify_repl_TBEs = False