riscv-bluespec-classic/bs/Bus/Client.bs
Yehowshua Immanuel d552934b95 Fixed grant bug
Just becasue we have a grant id doesn't mean that anything has actually
been granted...
2025-04-17 22:47:24 -04:00

113 lines
5.6 KiB
Haskell

package Client(
clientRouteRequest,
clientArbitSubmission
) where
import Types
import BusTypes
import TagEngine
import Vector
import Util
import Arbiter
import FIFO
import FIFOF
import SpecialFIFOs
import Printf
busRequestToAddr :: BusRequest -> Addr
busRequestToAddr req = case req of
BusReadRequest (ReadRequest addr _) -> addr
BusWriteRequest (WriteRequest addr _) -> addr
clientRouteRequest :: (Add n (TLog numServers) (TLog (TAdd numServers 1)))
=> Integer
-> FIFOF (TaggedBusRequest inFlightTransactions)
-> Vector numServers (Arbiter.Arbiter_IFC numClients)
-> Vector numClients (Arbiter.Arbiter_IFC (TAdd numServers 1))
-> (Addr -> Maybe (MkServerIdx numServers))
-> Rules
clientRouteRequest clientIdx clientReqQueue requestArbiterByServer responseArbiterByClient serverMap =
rules
(sprintf "client[%d] route request" clientIdx): when True ==> do
let clientRequest :: TaggedBusRequest inFlightTransactions
clientRequest = clientReqQueue.first
targetAddr :: Addr
targetAddr = busRequestToAddr |> clientRequest.busRequest
targetServerIdx :: Maybe (MkServerIdx numServers)
targetServerIdx = serverMap targetAddr
case targetServerIdx of
Just serverIdx -> do
let targetServerArbiter :: Arbiter.Arbiter_IFC numClients
targetServerArbiter = select requestArbiterByServer serverIdx
arbiterClientSlot :: Arbiter.ArbiterClient_IFC
arbiterClientSlot = select targetServerArbiter.clients clientIdx
arbiterClientSlot.request
-- We bypass sensing the request to the server instead option to form
-- a `BusError Unmapped` response which we request to send directly to
-- the appropiate client response queue.
Nothing -> do
let targetClientResponseArbiter :: Arbiter.Arbiter_IFC (TAdd numServers 1)
targetClientResponseArbiter = select responseArbiterByClient clientIdx
-- 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 :: Arbiter.ArbiterClient_IFC
clientResponseArbiterSlot = Vector.last targetClientResponseArbiter.clients
responseUnMapped :: BusResponse
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
clientArbitSubmission :: (Add n (TLog numServers) (TLog (TAdd numServers 1)))
=> Integer
-> FIFOF (TaggedBusRequest inFlightTransactions)
-> FIFOF (TaggedBusResponse inFlightTransactions)
-> Arbiter.Arbiter_IFC (TAdd numServers 1)
-> Vector numServers (FIFOF (MkClientTagType numClients, TaggedBusResponse inFlightTransactions))
-> Rules
clientArbitSubmission clientIdx clientReqQueue clientRespQueue clientRespArbiter submitRespQueues =
let grantedIdx :: UInt (TLog (TAdd numServers 1))
grantedIdx = unpack clientRespArbiter.grant_id
selectedServerInterface :: ArbiterClient_IFC
selectedServerInterface = select clientRespArbiter.clients grantedIdx
in
rules
(sprintf "client[%d] arbit submission" clientIdx): when selectedServerInterface.grant ==> do
let isClientRequest :: Bool
isClientRequest = grantedIdx == fromInteger (valueOf numServers)
if isClientRequest then do
let clientRequest :: TaggedBusRequest inFlightTransactions
clientRequest = clientReqQueue.first
responseUnMapped :: BusResponse
responseUnMapped = case clientRequest.busRequest of
BusReadRequest _ -> BusReadResponse (Left UnMapped)
BusWriteRequest _ -> BusWriteResponse (Left UnMapped)
response :: TaggedBusResponse inFlightTransactions
response = TaggedBusResponse { tag = clientRequest.tag; busResponse = responseUnMapped }
clientRespQueue.enq response
clientReqQueue.deq
else do
let grantedServerIdx :: MkServerIdx numServers
grantedServerIdx = truncate grantedIdx
selectedSubmitRespQueue :: FIFOF (MkClientTagType numClients, TaggedBusResponse inFlightTransactions)
selectedSubmitRespQueue = select submitRespQueues grantedServerIdx
response :: (MkClientTagType numClients, TaggedBusResponse inFlightTransactions)
response = selectedSubmitRespQueue.first
clientRespQueue.enq response.snd
selectedSubmitRespQueue.deq