def __init__(self, name , hostUnitRef, tlbSize, launchedTransSize):
super(TranslationEngine, self).__init__(name, hostUnitRef)
#TODO: put all these units into sub unit map
# instantiate all sub units:
self._tlb = TranslationTlb("tlb", self, 2, tlbSize)
self._trk = LaunchedTransactions("trk", self, 2, size=launchedTransSize)
self._mrg = TwoPortMerge("mrg", self, propagationDelay = 1)
#add ports
self.ports.addPort(Port("hit", self, Port.Direction.OUT))
self.ports.addPort(Port("miss", self, Port.Direction.OUT))
self.ports.addPort(Port("lookup", self, Port.Direction.IN))
self.ports.addPort(Port("update", self, Port.Direction.IN))
enableDump = True
# connect unit's ports and internal connections
Connector("cLookup", self, enableDump, self.ports["lookup"], self._tlb.ports["lookup"])
Connector("cUpdate", self, enableDump, self.ports["update"], self._trk.ports["dealloc"])
Connector("cHit", self, enableDump, self._mrg.ports["o"], self.ports["hit"])
Connector("cMiss", self, enableDump, self._trk.ports["miss"], self.ports["miss"])
Connector("cTlbHit", self, enableDump, self._tlb.ports["hit"], self._mrg.ports["i0"])
Connector("cTlbMiss", self, enableDump, self._tlb.ports["miss"], self._trk.ports["lookup"])
Connector("cTrkUpdate", self, enableDump, self._trk.ports["update"], self._tlb.ports["update"])
Connector("cTrkGenHit", self, enableDump, self._trk.ports["genHits"], self._mrg.ports["i1"])
class TranslationEngine(Unit):
"""
implements TranslationEngine. It is a HW unit that can handle
a single caching level. Units of this type will be cascade
one after another to handle all caching levels. (l0, ..., l4 etc)
"""
def __init__(self, name , hostUnitRef, tlbSize, launchedTransSize):
super(TranslationEngine, self).__init__(name, hostUnitRef)
#TODO: put all these units into sub unit map
# instantiate all sub units:
self._tlb = TranslationTlb("tlb", self, 2, tlbSize)
self._trk = LaunchedTransactions("trk", self, 2, size=launchedTransSize)
self._mrg = TwoPortMerge("mrg", self, propagationDelay = 1)
#add ports
self.ports.addPort(Port("hit", self, Port.Direction.OUT))
self.ports.addPort(Port("miss", self, Port.Direction.OUT))
self.ports.addPort(Port("lookup", self, Port.Direction.IN))
self.ports.addPort(Port("update", self, Port.Direction.IN))
enableDump = True
# connect unit's ports and internal connections
Connector("cLookup", self, enableDump, self.ports["lookup"], self._tlb.ports["lookup"])
Connector("cUpdate", self, enableDump, self.ports["update"], self._trk.ports["dealloc"])
Connector("cHit", self, enableDump, self._mrg.ports["o"], self.ports["hit"])
Connector("cMiss", self, enableDump, self._trk.ports["miss"], self.ports["miss"])
Connector("cTlbHit", self, enableDump, self._tlb.ports["hit"], self._mrg.ports["i0"])
Connector("cTlbMiss", self, enableDump, self._tlb.ports["miss"], self._trk.ports["lookup"])
Connector("cTrkUpdate", self, enableDump, self._trk.ports["update"], self._tlb.ports["update"])
Connector("cTrkGenHit", self, enableDump, self._trk.ports["genHits"], self._mrg.ports["i1"])
def lookup(self, request):
"""Does a lookup in internal data structures.
Returns a tuple of the form (isHit, result).
isHit is Boolean that is True in case of hit, False otherwise.
In case of hit:
- result is a Request-Object that holds translated address and
request.id
In case of miss:
- On 1st miss result will hold the address of provided request.
- On non 1st miss None will be returned. Cause there is at least
one translation request for the same address and this request
will be en-queued in launched transactions queue"""
resRequest = None
resLookup = False
isHit, translatedAddress = self._tlb.lookup(request)
if isHit:
resLookup = True
resRequest = Request(translatedAddress, request.id)
else: #miss flow bellow:
resLookup = False
isHit, resId = self._trk.lookup(request)
if isHit : #we've already flying transaction to same address
resRequest = None
else: # this is a first miss on that address => send miss
resRequest = request
return resLookup, resRequest
def update(self, translatedReq):
"""Updates internal tlbs to hold the translated address.
Returns: tuple of 2 elements (isHit, hitsList)
- isHit is true if translatedReq is being trucked by this engine.
- hitsList is non-empty list when isHit==True. This list of generated
hits i.e. request-objects. This list will have at least one element
(the one with same id as update.id).
In case when additional transaction have arrived to translate the
address that's already in-flight, additional request-objects will be
added to returned list.
"""
isHit, update, hitsList = self._trk.dealloc(translatedReq)
if isHit == True:
self._tlb.update(update) #send the update to tlb
return isHit, hitsList