xref: /gem5/src/mem/cache/prefetch/Prefetcher.py

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# Authors: Ron Dreslinski

from ClockedObject import ClockedObject
from m5.params import *
from m5.proxy import *

class BasePrefetcher(ClockedObject):
    type = 'BasePrefetcher'
    abstract = True
    cxx_header = "mem/cache/prefetch/base.hh"
    size = Param.Int(100,
         "Number of entries in the hardware prefetch queue")
    cross_pages = Param.Bool(False,
         "Allow prefetches to cross virtual page boundaries")
    serial_squash = Param.Bool(False,
         "Squash prefetches with a later time on a subsequent miss")
    degree = Param.Int(1,
         "Degree of the prefetch depth")
    latency = Param.Cycles('1', "Latency of the prefetcher")
    use_master_id = Param.Bool(True,
         "Use the master id to separate calculations of prefetches")
    data_accesses_only = Param.Bool(False,
         "Only prefetch on data not on instruction accesses")
    on_miss_only = Param.Bool(False,
         "Only prefetch on miss (as opposed to always)")
    on_read_only = Param.Bool(False,
         "Only prefetch on read requests (write requests ignored)")
    on_prefetch = Param.Bool(True,
         "Let lower cache prefetcher train on prefetch requests")
    inst_tagged = Param.Bool(True,
         "Perform a tagged prefetch for instruction fetches always")
    sys = Param.System(Parent.any, "System this prefetcher belongs to")

class StridePrefetcher(BasePrefetcher):
    type = 'StridePrefetcher'
    cxx_class = 'StridePrefetcher'
    cxx_header = "mem/cache/prefetch/stride.hh"

class TaggedPrefetcher(BasePrefetcher):
    type = 'TaggedPrefetcher'
    cxx_class = 'TaggedPrefetcher'
    cxx_header = "mem/cache/prefetch/tagged.hh"