diff --git a/bs/Bus.bs b/bs/Bus.bs index 3afe1e8..4a516f4 100644 --- a/bs/Bus.bs +++ b/bs/Bus.bs @@ -25,8 +25,13 @@ dummyRule = "test rule": when True ==> do $display "test rule" +data DispatchFromClient inFlightTransactions numServers + = DispatchRequest (TaggedBusRequest inFlightTransactions) (MkServerIdx numServers) + | DispatchResponse (TaggedBusResponse inFlightTransactions) + deriving (Bits, Eq, FShow) + -- we need a way to make serverMap safer... -mkBus :: (Addr -> Maybe ServerIdx) +mkBus :: (Addr -> Maybe (MkServerIdx numServers)) -> Module (Bus inFlightTransactions numClients numServers) mkBus serverMap = do -- Tag engines for each client to manage transaction tags @@ -43,6 +48,13 @@ mkBus serverMap = do responseArbiterByClient :: Vector numClients (Arbiter.Arbiter_IFC (TAdd numServers 1)) responseArbiterByClient <- replicateM (mkArbiter False) + -- After we inspect the head/oldest request in the `clientRequestQueues` and perform an + -- arbiter request to the destination arbiter, we need to inspect for grant in another + -- rule as I don't believe grant and request can be called simultaneously. + -- The following vector allows us to move + dispatchByClient :: Vector numClients (Wire (DispatchFromClient inFlightTransactions numServers)) + dispatchByClient <- replicateM mkWire + -- There are `numServer` servers, each of which needs its own arbiter as -- there are up to `numClient` clients that may wish to submit a response -- to a given client. @@ -76,9 +88,11 @@ mkBus serverMap = do clientRequest = selectedClientRequestQueue.first targetAddr :: Addr = busRequestToAddr |> clientRequest.busRequest - targetServerIdx :: (Maybe ServerIdx) = serverMap targetAddr - -- $display "clientRequest" (fshow clientRequest) - $display "Bus.bs:81" (fshow clientRequest) + targetServerIdx :: (Maybe (MkServerIdx numServers)) = serverMap targetAddr + + dispatchByClientWire :: Wire (DispatchFromClient inFlightTransactions numServers) + dispatchByClientWire = (select dispatchByClient clientIdx) + case targetServerIdx of Just serverIdx -> do let @@ -87,22 +101,30 @@ mkBus serverMap = do arbiterClientSlot :: Arbiter.ArbiterClient_IFC arbiterClientSlot = (select targetServerArbiter.clients clientIdx) arbiterClientSlot.request + dispatchByClientWire := DispatchRequest clientRequest serverIdx Nothing -> do let - idx = fromInteger clientIdx - targetClientResponseArbiter :: Arbiter.Arbiter_IFC numClients - targetClientResponseArbiter = (select responseArbiterByClient idx) + targetClientResponseArbiter :: Arbiter.Arbiter_IFC (TAdd numServers 1) + targetClientResponseArbiter = (select responseArbiterByClient clientIdx) clientResponseArbiterSlot :: Arbiter.ArbiterClient_IFC - -- arbiters 0 to n-1 are where `n:=numServer` are reserved + -- arbiters 0 to n-1 where `n:=numServer` are reserved -- for servers to make requests to. Arbiter n is reserved for -- when this rule needs to skip making a request to a server -- and should instead forward the `BusError UnMapped` response -- back to the client. Vector.last selects arbiter `n` - clientResponseArbiterSlot = Vector.last targetClientResponseArbiter + clientResponseArbiterSlot = Vector.last targetClientResponseArbiter.clients + responseUnMapped = case clientRequest.busRequest of + BusReadRequest _ -> BusReadResponse (Left UnMapped) + BusWriteRequest _ -> BusWriteResponse (Left UnMapped) + response :: TaggedBusResponse inFlightTransactions + response = TaggedBusResponse { + tag = clientRequest.tag; + busResponse = responseUnMapped + } + clientResponseArbiterSlot.request - - + dispatchByClientWire := DispatchResponse response addRules |> foldr (<+>) (rules {}) clientRules diff --git a/bs/BusTypes.bs b/bs/BusTypes.bs index ed6de3b..7746669 100644 --- a/bs/BusTypes.bs +++ b/bs/BusTypes.bs @@ -1,6 +1,6 @@ package BusTypes( Bus(..), - ServerIdx, + MkServerIdx, MkClientTagType, BusClient(..), BusServer(..), BusRequest(..), BusResponse(..), @@ -14,7 +14,7 @@ import Vector import TagEngine type MkClientTagType numClients = (UInt (TLog numClients)) -type ServerIdx = Integer +type MkServerIdx numServers = (UInt (TLog numServers)) data BusError = UnMapped diff --git a/diagrams/bus.drawio b/diagrams/bus.drawio index 97ba9e7..fb90bc2 100644 --- a/diagrams/bus.drawio +++ b/diagrams/bus.drawio @@ -1,272 +1,278 @@ - + - + - + + + + + + + - + - - + + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - - - - + + + + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + @@ -277,7 +283,7 @@ - + @@ -288,7 +294,7 @@ - + @@ -299,7 +305,7 @@ - + @@ -310,50 +316,84 @@ - - - - + + + + - + - - - - + + + + - + - - - - + + + + - + - - - - + + + + - - + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +