Merge pull request 'implement_Bus_alt1' (#16) from implement_Bus_alt1 into main

Reviewed-on: #16

.gitignore

@@ -1,4 +1,5 @@
 *.vcd
+*.bkp
 *.so
 
 # bluespec files

Makefile

@@ -51,7 +51,6 @@ BSC_COMP_FLAGS += \
 		-aggressive-conditions  \
 		-no-warn-action-shadowing  \
 		-check-assert  \
-		-cpp \
 		-show-schedule \
 		+RTS -K128M -RTS  -show-range-conflict \
 		$(BSC_COMP_FLAG1)  $(BSC_COMP_FLAG2)  $(BSC_COMP_FLAG3)

bs/Bus.bs

@@ -1,7 +1,287 @@
-package Bus(a) where
+package Bus(mkBus, Bus(..)) where
 
 import Types
 import BusTypes
+import TagEngine
+import Vector
+import Util
+import Arbiter
+import FIFO
+import FIFOF
+import SpecialFIFOs
+import Printf
 
-a :: UInt 5
-a = 3
+busRequestToAddr :: BusRequest -> Addr
+busRequestToAddr req = case req of
+    BusReadRequest (ReadRequest addr _) -> addr
+    BusWriteRequest (WriteRequest addr _) -> addr
+
+-- Create a Bus Module that supports multiple clients and servers
+-- submitting requests and simultaneously returning responses.
+-- Responses can be consumed by clients out of order as all client
+-- submitted requests are tagged - and servers keep that tag
+-- when responding.
+mkBus :: (Add n (TLog numServers) (TLog (TAdd numServers 1)))
+      => (Addr -> Maybe (MkServerIdx numServers))
+      -> Module (Bus inFlightTransactions numClients numServers)
+mkBus serverMap = do
+    -- Tag engines for each client to manage transaction tags
+    tagEngineByClientVec :: Vector numClients (TagEngine inFlightTransactions)
+    tagEngineByClientVec <- replicateM mkTagEngine
+
+    -- There are `numClients` clients, each of which needs its own arbiter as
+    -- there are up to `numServer` servers that may wish to submit a response
+    -- to a given client. Furthermore the rule that routes client requests to
+    -- servers makes for another potential requestor as it may determine that
+    -- a request is unmappable and instead opt to form and submit a
+    -- `BusError UnMapped` response directly to a client response arbiter. Thus
+    -- we must arbit between a total of `numServers + 1` requestors.
+    responseArbiterByClient :: Vector numClients (Arbiter.Arbiter_IFC (TAdd numServers 1))
+    responseArbiterByClient <- replicateM (mkArbiter False)
+
+    -- 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 server.
+    requestArbiterByServer :: Vector numServers (Arbiter.Arbiter_IFC numClients)
+    requestArbiterByServer <- replicateM (mkArbiter False)
+
+    dummyVar :: Reg(Bool)
+    dummyVar <- mkReg False
+
+    -- Queues to hold requests from clients
+    clientRequestQueues :: Vector numClients (FIFOF (TaggedBusRequest inFlightTransactions))
+    clientRequestQueues <- replicateM (mkSizedBypassFIFOF (valueOf inFlightTransactions))
+
+    -- Queues to hold responses to clients
+    clientResponseQueues :: Vector numClients (FIFOF (TaggedBusResponse inFlightTransactions))
+    clientResponseQueues <- replicateM (mkSizedBypassFIFOF (valueOf inFlightTransactions))
+
+    -- The following two vectors of FIFOs make it easier to push/pull data to/from internal
+    -- server methods:
+    consumeRequestQueues :: Vector numServers (
+                                        FIFOF (
+                                            MkClientTagType numClients,
+                                            TaggedBusRequest inFlightTransactions
+                                            )
+                                        )
+    consumeRequestQueues <- replicateM mkBypassFIFOF
+
+    submitResponseQueues :: Vector numServers (
+                                        FIFOF (
+                                            MkClientTagType numClients,
+                                            TaggedBusResponse inFlightTransactions
+                                            )
+                                        )
+    submitResponseQueues <- replicateM mkBypassFIFOF
+
+    let clientRules :: Vector numClients (Rules)
+        clientRules = genWith $ \clientIdx ->
+            let
+                selectedClientRequestQueue :: FIFOF (TaggedBusRequest inFlightTransactions)
+                selectedClientRequestQueue = (select clientRequestQueues clientIdx)
+            in
+                rules
+                    (sprintf "client[%d] route request" clientIdx): when True ==> do
+                        let
+                            clientRequest :: TaggedBusRequest inFlightTransactions
+                            clientRequest = selectedClientRequestQueue.first
+
+                            targetAddr :: Addr = busRequestToAddr |> clientRequest.busRequest
+                            targetServerIdx :: (Maybe (MkServerIdx numServers)) = 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
+                            Nothing -> do
+                                let
+                                    targetClientResponseArbiter :: Arbiter.Arbiter_IFC (TAdd numServers 1)
+                                    targetClientResponseArbiter =  (select responseArbiterByClient clientIdx)
+
+                                    clientResponseArbiterSlot :: Arbiter.ArbiterClient_IFC
+                                    -- 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.clients
+                                let
+                                    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
+
+                    (sprintf "client[%d] arbit submission" clientIdx): when True ==> do
+                        let
+                            selectedClientResponseArbiter :: Arbiter.Arbiter_IFC (TAdd numServers 1)
+                            selectedClientResponseArbiter = (select responseArbiterByClient clientIdx)
+
+                            selectedClientResponseQueue :: FIFOF (TaggedBusResponse inFlightTransactions)
+                            selectedClientResponseQueue = (select clientResponseQueues clientIdx)
+
+                            -- `TAdd numServers 1` because we can receive request from all servers
+                            -- as well as a bypass requests from our one corresponding client request
+                            -- queue
+                            grantedIdx :: UInt (TLog (TAdd numServers 1))
+                            grantedIdx = unpack selectedClientResponseArbiter.grant_id
+
+                            isClientRequest :: Bool
+                            isClientRequest = grantedIdx == fromInteger (valueOf numServers)
+                        if isClientRequest then do
+                            let
+                                clientRequest :: TaggedBusRequest inFlightTransactions
+                                clientRequest = selectedClientRequestQueue.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
+                                }
+                            selectedClientResponseQueue.enq response
+                            selectedClientRequestQueue.deq
+                        else do
+                            let
+                                grantedServerIdx :: MkServerIdx numServers
+                                grantedServerIdx = truncate grantedIdx
+
+                                selectedSubmitResponseQueue :: FIFOF (
+                                                                    MkClientTagType numClients,
+                                                                    TaggedBusResponse inFlightTransactions
+                                                                )
+                                selectedSubmitResponseQueue = (select submitResponseQueues grantedServerIdx)
+
+                                response :: (MkClientTagType numClients, TaggedBusResponse inFlightTransactions)
+                                response = selectedSubmitResponseQueue.first
+                            selectedClientResponseQueue.enq response.snd
+                            selectedSubmitResponseQueue.deq
+
+    let serverRules :: Vector numServers (Rules)
+        serverRules = genWith $ \serverIdx ->
+            let
+                selectedServerArbiter :: Arbiter.Arbiter_IFC numClients
+                selectedServerArbiter = (select requestArbiterByServer serverIdx)
+
+                selectedConsumeRequestQueue :: FIFOF (
+                                                MkClientTagType numClients,
+                                                TaggedBusRequest inFlightTransactions
+                                                )
+                selectedConsumeRequestQueue = (select consumeRequestQueues serverIdx)
+            in
+                rules
+                    (sprintf "server[%d] arbit requests" serverIdx): when True ==> do
+                        let
+                            grantedClientIdx :: MkClientTagType numClients
+                            grantedClientIdx = unpack selectedServerArbiter.grant_id
+
+                            selectedClientRequestQueue :: FIFOF (TaggedBusRequest inFlightTransactions)
+                            selectedClientRequestQueue = (select clientRequestQueues grantedClientIdx)
+
+                            clientRequest :: TaggedBusRequest inFlightTransactions
+                            clientRequest = selectedClientRequestQueue.first
+
+                        selectedConsumeRequestQueue.enq (grantedClientIdx, clientRequest)
+                        selectedClientRequestQueue.deq
+
+                    (sprintf "server[%d] route response" serverIdx): when True ==> do
+                        let
+                            selectedSubmitResponseQueue :: FIFOF (
+                                                                MkClientTagType numClients,
+                                                                TaggedBusResponse inFlightTransactions
+                                                            )
+                            selectedSubmitResponseQueue = (select submitResponseQueues serverIdx)
+
+                            response :: (MkClientTagType numClients, TaggedBusResponse inFlightTransactions)
+                            response = selectedSubmitResponseQueue.first
+
+                            clientTag :: MkClientTagType numClients
+                            clientTag = response.fst
+
+                            targetClientResponseArbiter :: Arbiter.Arbiter_IFC (TAdd numServers 1)
+                            targetClientResponseArbiter = (select responseArbiterByClient clientTag)
+
+                            arbiterClientSlot :: Arbiter.ArbiterClient_IFC
+                            arbiterClientSlot = (select targetClientResponseArbiter.clients serverIdx)
+                        arbiterClientSlot.request
+
+    addRules |> foldr (<+>) (rules {}) clientRules
+    addRules |> foldr (<+>) (rules {}) serverRules
+
+    -- Client interface vector
+    let clients :: Vector numClients (BusClient inFlightTransactions)
+        clients = genWith $ \clientIdx ->
+            let
+                selectedClientRequestQueue :: FIFOF (TaggedBusRequest inFlightTransactions)
+                selectedClientRequestQueue = (select clientRequestQueues clientIdx)
+
+                selectedClientResponseQueue :: FIFOF (TaggedBusResponse inFlightTransactions)
+                selectedClientResponseQueue = (select clientResponseQueues clientIdx)
+
+                selectedTagEngine :: TagEngine inFlightTransactions
+                selectedTagEngine = (select tagEngineByClientVec clientIdx)
+            in
+                interface BusClient
+                    submitRequest   :: BusRequest
+                                    -> ActionValue (MkTagType inFlightTransactions)
+                    submitRequest busRequest = do
+                        tag <- selectedTagEngine.requestTag
+                        let taggedReuqest = TaggedBusRequest {tag = tag; busRequest = busRequest}
+                        selectedClientRequestQueue.enq taggedReuqest
+                        return tag
+
+                    consumeResponse :: ActionValue (TaggedBusResponse inFlightTransactions)
+                    consumeResponse = do
+                        let
+                            busResponse :: (TaggedBusResponse inFlightTransactions)
+                            busResponse = selectedClientResponseQueue.first
+                        selectedTagEngine.retireTag busResponse.tag
+                        selectedClientResponseQueue.deq
+                        return busResponse
+
+    -- Server interface vector
+    let servers :: Vector numServers (BusServer inFlightTransactions numClients)
+        servers = genWith $ \serverIdx ->
+            let
+                selectedConsumeRequestQueue :: FIFOF (
+                                                MkClientTagType numClients,
+                                                TaggedBusRequest inFlightTransactions
+                                                )
+                selectedConsumeRequestQueue = (select consumeRequestQueues serverIdx)
+            in
+                interface BusServer
+                    consumeRequest  :: ActionValue (
+                                        MkClientTagType numClients,
+                                        TaggedBusRequest inFlightTransactions
+                                        )
+                    consumeRequest = do
+                        selectedConsumeRequestQueue.deq
+                        return selectedConsumeRequestQueue.first
+
+                    submitResponse  :: ( MkClientTagType numClients,
+                                        TaggedBusResponse inFlightTransactions
+                                        ) -> Action
+                    submitResponse (clientTag, taggedBusResponse) = do
+                        let
+                            selectedSubmitResponseQueue :: FIFOF (
+                                                                MkClientTagType numClients,
+                                                                TaggedBusResponse inFlightTransactions
+                                                            )
+                            selectedSubmitResponseQueue = (select submitResponseQueues serverIdx)
+                        selectedSubmitResponseQueue.enq (clientTag, taggedBusResponse)
+
+    return $
+        interface Bus
+            clients = clients
+            servers = servers

bs/BusTypes.bs

@@ -1,12 +1,20 @@
 package BusTypes(
-    BusVal(..),
-    BusError(..),
-    TransactionSize(..),
-    ReadRequest(..),
-    WriteRequest(..)
+    Bus(..),
+    MkServerIdx,
+    MkClientTagType,
+    BusClient(..), BusServer(..),
+    BusRequest(..), BusResponse(..),
+    ReadRequest(..), ReadResponse(..), WriteRequest(..), WriteResponse(..),
+    BusVal(..), BusError(..), TransactionSize(..),
+    TaggedBusRequest(..), TaggedBusResponse(..)
     ) where
 
 import Types
+import Vector
+import TagEngine
+
+type MkClientTagType numClients = (UInt (TLog numClients))
+type MkServerIdx numServers = (UInt (TLog numServers))
 
 data BusError
     = UnMapped
@@ -40,7 +48,7 @@ type WriteResponse = Either BusError ()
 
 data BusRequest
   = BusReadRequest      ReadRequest
-  | WriteReadRequest    WriteRequest
+  | BusWriteRequest     WriteRequest
   deriving (Bits, Eq, FShow)
 
 data BusResponse
@@ -48,21 +56,60 @@ data BusResponse
   | BusWriteResponse    WriteResponse
   deriving (Bits, Eq, FShow)
 
-interface BusMaster =
-  -- The Bus arbiter will call the Bus Master's request method
-  -- if and only if it's the Bus Master's turn to make a request, and the Bus Master
-  -- has a request to make.
-  -- It is up to the BusMaster to guard it's request method such that calling
-  -- it's request method is only valid when the BusMaster has a request to make.
-  -- This has implications about for the implementor of BusMaster, namely, that it
-  -- should hold its request until it's request method gets called.
-  request  :: BusRequest
-  -- From the masters's perspective, the response should not be called by the
-  -- arbiter until the master is ready to accept the response. In other words,
-  -- response should be guarded by the client.
-  response :: BusResponse -> Action
+struct TaggedBusRequest inFlightTransactions =
+    { tag :: (MkTagType inFlightTransactions);
+      busRequest :: BusRequest
+    }
+    deriving (Bits, Eq, FShow)
 
-type Token = UInt 5
+struct TaggedBusResponse inFlightTransactions =
+    { tag :: (MkTagType inFlightTransactions);
+      busResponse :: BusResponse
+    }
+    deriving (Bits, Eq, FShow)
 
-a :: UInt 5
-a = 3
+-- # BusClient.submitRequest
+--   * The bus client calls the `submitRequest` method of the `BusClient` interface
+--     with the `BusRequest` it wishes to submit and immediately recieves back
+--     a transaction-duration-unqiue tag that it can later correlate with the
+--     returned response should responses arrive out of order(OOO). OOO can
+--     happen if a bus server is is able to process bus requests faster than
+--     other bus servers for example.
+-- # BusClient.consumeResponse
+--   * The bus client is able to consume a response when a response is available.
+--     Responses are tagged with the tag given to bus client when it called
+--     `submitRequest`
+interface (BusClient :: # -> *) inFlightTransactions =
+  submitRequest   :: BusRequest
+                  -> ActionValue (MkTagType inFlightTransactions)
+  consumeResponse :: ActionValue (TaggedBusResponse inFlightTransactions)
+
+-- # BusServer.consumeRequest
+--   * The bus server calls the `consumeRequest` method of the `BusServer` interface
+--     to retrieve a pending bus request initiated by a client. It immediately
+--     receives a tuple containing a transaction-duration-unique tag
+--     (associated with the original request) and the `BusRequest` itself. This
+--     tag is used to track the transaction and correlate it with the eventual
+--     response.
+-- # BusServer.submitResponse
+--   * The bus server calls the `submitResponse` method to send a `BusResponse`
+--     back to the originating client. The method takes a tuple containing:
+--     - A client tag (of type `MkClientTagType numClients`) identifying the
+--       client that submitted the request.
+--     - The `BusResponse` containing the result of the request (either a read
+--       or write response).
+--     - The transaction tag (of type `transactionTagType`) that matches the tag
+--       received from `consumeRequest`, ensuring the response is correctly
+--       associated with the original request.
+interface (BusServer :: # -> # -> *) inFlightTransactions numClients =
+  consumeRequest  :: ActionValue (
+                      MkClientTagType numClients,
+                      TaggedBusRequest inFlightTransactions
+                      )
+  submitResponse  :: ( MkClientTagType numClients,
+                       TaggedBusResponse inFlightTransactions
+                       ) -> Action
+
+interface (Bus :: # -> # -> # -> *) inFlightTransactions numClients numServers =
+  clients :: Vector numClients (BusClient inFlightTransactions)
+  servers :: Vector numServers (BusServer inFlightTransactions numClients)

bs/ClkDivider.bs

@@ -1,4 +1,8 @@
-package ClkDivider(mkClkDivider, ClkDivider(..)) where
+package ClkDivider(
+  mkClkDivider,
+  MkClkDivType,
+  ClkDivider(..)
+  ) where
 
 interface (ClkDivider :: # -> *) hi =
   {
@@ -7,11 +11,13 @@ interface (ClkDivider :: # -> *) hi =
   ;isHalfCycle :: Bool
   }
 
+type MkClkDivType maxCycles = (UInt (TLog (TAdd 1 maxCycles)))
+
 mkClkDivider :: Handle -> Module (ClkDivider hi)
 mkClkDivider fileHandle = do
-    counter <- mkReg(0 :: UInt (TLog hi))   
-    let hi_value :: UInt (TLog hi) = (fromInteger $ valueOf hi)
-    let half_hi_value :: UInt (TLog hi) = (fromInteger $ valueOf (TDiv hi 2))
+    counter <- mkReg(0 :: MkClkDivType hi)
+    let hi_value :: (MkClkDivType hi) = (fromInteger $ valueOf hi)
+    let half_hi_value :: (MkClkDivType hi) = (fromInteger $ valueOf (TDiv hi 2))
 
     let val :: Real = (fromInteger $ valueOf hi)
     let msg = "Clock Div Period : " + (realToString val) + "\n"

bs/Core.bs

@@ -11,13 +11,13 @@ interface (Core :: # -> *) clkFreq = {
 
 mkCore :: Module (Core clkFreq)
 mkCore = do
-  counter    :: Reg (UInt (TLog clkFreq)) <- mkReg 0
+  counter    :: Reg (MkClkDivType clkFreq) <- mkReg 0
   tickSecond :: Wire Bool    <- mkDWire False
   uartOut    :: Wire (Bit 8) <- mkWire;
   ledOut     :: Reg (Bit 8)  <- mkReg 0
 
   let clkFreqInt :: Integer = valueOf clkFreq
-  let clkFreqUInt :: UInt (TLog clkFreq) = fromInteger clkFreqInt
+  let clkFreqUInt :: (MkClkDivType clkFreq) = fromInteger clkFreqInt
   let val :: Real = fromInteger clkFreqInt
 
   messageM $ "mkCore clkFreq" + realToString val

bs/TagEngine.bs

@@ -1,4 +1,5 @@
 package TagEngine(
+    MkTagType,
     TagEngine(..),
     Util.BasicResult(..),
     mkTagEngine) where
@@ -6,14 +7,13 @@ package TagEngine(
 import Vector
 import Util
 import FIFO
-import FIFOF
 import SpecialFIFOs
 
-#define UIntLog2N(n) (UInt (TLog n))
+type MkTagType numTags = (UInt (TLog (TAdd 1 numTags)))
 
 interface (TagEngine :: # -> *) numTags =
-    requestTag :: ActionValue UIntLog2N(numTags)
-    retireTag  :: UIntLog2N(numTags) -> Action
+    requestTag :: ActionValue (MkTagType numTags)
+    retireTag  :: (MkTagType numTags) -> Action
 
 -- The tag engine returns a tag that is unique for the duration of
 -- the lifetime of the tag. Useful when you need to tag transactions
@@ -34,7 +34,7 @@ mkTagEngine = do
     -- to TagEngine where `n := maxTagCount`.
     initialTagDistributor <- mkReg (Just (maxTagCount - 1))  -- Distributes initial tags
     retireQueue <- mkBypassFIFO  -- Queue for tags being retired
-    freeTagQueue <- mkSizedFIFOF maxTagCount  -- Queue of available tags
+    freeTagQueue <- mkSizedFIFO maxTagCount  -- Queue of available tags
 
     -- Signals
     retireSignal <- mkRWire  -- Signals a tag retirement
@@ -44,7 +44,7 @@ mkTagEngine = do
     debugOnce <- mkReg True
 
     -- Rules
-    addRules $
+    addRules |>
         rules
             "debug_initial_state": when debugOnce ==> do
                 $display "tagUsage: " (fshow (readVReg tagUsage))
@@ -77,9 +77,9 @@ mkTagEngine = do
                     (Nothing, Nothing) -> action {}
 
     -- Interface
-    return $
+    return |>
         interface TagEngine
-            requestTag :: ActionValue UIntLog2N(numTags)
+            requestTag :: ActionValue (MkTagType numTags)
             requestTag = do
                 case initialTagDistributor of
                     Just 0 -> do
@@ -100,7 +100,7 @@ mkTagEngine = do
             -- so it is advisable that the caller of `retireTag` only attempt to retire valid tags.
             -- Internally, the tagEngine will keep a correct and consistent state since TagEngine
             -- validates tags before attempting to retire them.
-            retireTag :: UIntLog2N(numTags) -> Action
+            retireTag :: (MkTagType numTags) -> Action
             retireTag tag =
                 do
                     let

bs/Top.bs

@@ -10,6 +10,9 @@ import TagEngine
 import List
 import ActionSeq
 
+import Vector
+import BusTypes
+
 import TagEngineTester
 
 type FCLK = 25000000
@@ -57,11 +60,18 @@ mkTop = do
 mkSim :: Module Empty
 mkSim = do
   _ :: Empty <- mkTagEngineTester
-  initCFunctions :: Reg Bool <- mkReg False;
-  core             :: Core FCLK <- mkCore;
+  initCFunctions :: Reg Bool <- mkReg False
+  core             :: Core FCLK <- mkCore
+  let busMap _ = Just 0
+  bus :: (Bus 4 2 2) <- mkBus busMap
 
   addRules $
     rules
+      "test bus": when True ==>
+        do
+          let server = (Vector.select bus.servers 0)
+          result <- server.consumeRequest
+          $display "Top.bs:74" (fshow result)
       "initCFunctionsOnce":  when not initCFunctions ==>
         do
           initTerminal

diagrams/bus.drawio

@@ -0,0 +1,423 @@
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+  <diagram name="simplified" id="y4uZzcGV7WDpy27g0Dv6">
+    <mxGraphModel dx="673" dy="413" grid="1" gridSize="10" guides="1" tooltips="1" connect="1" arrows="1" fold="1" page="1" pageScale="1" pageWidth="850" pageHeight="1100" math="0" shadow="0">
+      <root>
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+        </mxCell>
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+          <mxGeometry x="80" y="80" width="200" height="40" as="geometry" />
+        </mxCell>
+        <mxCell id="DDLsznhKMAXYVWb-8vYK-236" value="submit&lt;div&gt;request&lt;/div&gt;" style="endArrow=classic;html=1;rounded=0;labelBackgroundColor=default;fontSize=10;" parent="1" edge="1">
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+            <mxPoint x="130" y="120" as="sourcePoint" />
+            <mxPoint x="130.00000000000006" y="380" as="targetPoint" />
+            <mxPoint as="offset" />
+          </mxGeometry>
+        </mxCell>
+        <mxCell id="DDLsznhKMAXYVWb-8vYK-237" value="&lt;div&gt;consume&lt;/div&gt;&lt;div&gt;response&lt;/div&gt;" style="endArrow=classic;html=1;rounded=0;labelBackgroundColor=default;fontSize=10;" parent="1" edge="1">
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+          </mxGeometry>
+        </mxCell>
+        <mxCell id="DDLsznhKMAXYVWb-8vYK-238" value="" style="group;labelBackgroundColor=default;fontSize=10;" parent="1" vertex="1" connectable="0">
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