Explicitly make sync a Moore machine

clash-cores/src/Clash/Cores/Sgmii/Sync.hs

@@ -1,3 +1,4 @@
+{-# LANGUAGE OverloadedRecordDot #-}
 {-# LANGUAGE RecordWildCards #-}
 {-# LANGUAGE ViewPatterns #-}
 
@@ -95,16 +96,15 @@ commas =
 
 -- | State transition function for 'sync'. Takes the state as defined in
 --   'SyncState', a the new incoming code group from the SerDes-block and
---   returns a tuple containing the next state and the outputs as defined in
---   Clause 36 of IEEE 802.3
+--   returns the next state as defined in Clause 36 of IEEE 802.3.
 syncT ::
   -- | Current state
   SyncState ->
   -- | New input codegroup
   BitVector 10 ->
   -- | New state and output tuple
-  (SyncState, (SyncState, BitVector 10, Bool, DataWord, Even, SyncStatus))
-syncT self@LossOfSync{..} cg = (nextState, out)
+  SyncState
+syncT LossOfSync{..} cg = nextState
  where
   nextState
     | cg `notElem` commas = LossOfSync cg rd dw rxEven
@@ -113,10 +113,7 @@ syncT self@LossOfSync{..} cg = (nextState, out)
 
   (rd, dw) = ebTbDecode _rd cg
   rxEven = nextEven _rxEven
-  syncStatus = Fail
-
-  out = (self, _cg, _rd, _dw, rxEven, syncStatus)
-syncT self@CommaDetect1{..} cg = (nextState, out)
+syncT CommaDetect1{..} cg = nextState
  where
   nextState
     | not (isDw dw) = LossOfSync cg rd dw rxEven
@@ -125,10 +122,7 @@ syncT self@CommaDetect1{..} cg = (nextState, out)
 
   (rd, dw) = ebTbDecode _rd cg
   rxEven = Even
-  syncStatus = Fail
-
-  out = (self, _cg, _rd, _dw, rxEven, syncStatus)
-syncT self@AcquireSync1{..} cg = (nextState, out)
+syncT AcquireSync1{..} cg = nextState
  where
   nextState
     | not (isValidDw dw) = LossOfSync cg rd dw rxEven
@@ -139,10 +133,7 @@ syncT self@AcquireSync1{..} cg = (nextState, out)
 
   (rd, dw) = ebTbDecode _rd cg
   rxEven = nextEven _rxEven
-  syncStatus = Fail
-
-  out = (self, _cg, _rd, _dw, rxEven, syncStatus)
-syncT self@CommaDetect2{..} cg = (nextState, out)
+syncT CommaDetect2{..} cg = nextState
  where
   nextState
     | not (isDw dw) = LossOfSync cg rd dw rxEven
@@ -151,10 +142,7 @@ syncT self@CommaDetect2{..} cg = (nextState, out)
 
   (rd, dw) = ebTbDecode _rd cg
   rxEven = Even
-  syncStatus = Fail
-
-  out = (self, _cg, _rd, _dw, rxEven, syncStatus)
-syncT self@AcquireSync2{..} cg = (nextState, out)
+syncT AcquireSync2{..} cg = nextState
  where
   nextState
     | not (isValidDw dw) = LossOfSync cg rd dw rxEven
@@ -165,10 +153,7 @@ syncT self@AcquireSync2{..} cg = (nextState, out)
 
   (rd, dw) = ebTbDecode _rd cg
   rxEven = nextEven _rxEven
-  syncStatus = Fail
-
-  out = (self, _cg, _rd, _dw, rxEven, syncStatus)
-syncT self@CommaDetect3{..} cg = (nextState, out)
+syncT CommaDetect3{..} cg = nextState
  where
   nextState
     | not (isDw dw) = LossOfSync cg rd dw rxEven
@@ -177,10 +162,7 @@ syncT self@CommaDetect3{..} cg = (nextState, out)
 
   (rd, dw) = ebTbDecode _rd cg
   rxEven = Even
-  syncStatus = Fail
-
-  out = (self, _cg, _rd, _dw, rxEven, syncStatus)
-syncT self@SyncAcquired1{..} cg = (nextState, out)
+syncT SyncAcquired1{..} cg = nextState
  where
   nextState
     | not (isValidDw dw) = SyncAcquired2 cg rd dw rxEven
@@ -191,10 +173,7 @@ syncT self@SyncAcquired1{..} cg = (nextState, out)
 
   (rd, dw) = ebTbDecode _rd cg
   rxEven = nextEven _rxEven
-  syncStatus = Ok
-
-  out = (self, _cg, _rd, _dw, rxEven, syncStatus)
-syncT self@SyncAcquired2{..} cg = (nextState, out)
+syncT SyncAcquired2{..} cg = nextState
  where
   nextState
     | not (isValidDw dw) = SyncAcquired3 cg rd dw rxEven
@@ -205,11 +184,8 @@ syncT self@SyncAcquired2{..} cg = (nextState, out)
 
   (rd, dw) = ebTbDecode _rd cg
   rxEven = nextEven _rxEven
-  syncStatus = Ok
   goodCgs = 0
-
-  out = (self, _cg, _rd, _dw, rxEven, syncStatus)
-syncT self@SyncAcquired2A{..} cg = (nextState, out)
+syncT SyncAcquired2A{..} cg = nextState
  where
   nextState
     | not (isValidDw dw) = SyncAcquired3 cg rd dw rxEven
@@ -224,11 +200,8 @@ syncT self@SyncAcquired2A{..} cg = (nextState, out)
 
   (rd, dw) = ebTbDecode _rd cg
   rxEven = nextEven _rxEven
-  syncStatus = Ok
   goodCgs = _goodCgs + 1
-
-  out = (self, _cg, _rd, _dw, rxEven, syncStatus)
-syncT self@SyncAcquired3{..} cg = (nextState, out)
+syncT SyncAcquired3{..} cg = nextState
  where
   nextState
     | not (isValidDw dw) = SyncAcquired4 cg rd dw rxEven
@@ -239,11 +212,8 @@ syncT self@SyncAcquired3{..} cg = (nextState, out)
 
   (rd, dw) = ebTbDecode _rd cg
   rxEven = nextEven _rxEven
-  syncStatus = Ok
   goodCgs = 0
-
-  out = (self, _cg, _rd, _dw, rxEven, syncStatus)
-syncT self@SyncAcquired3A{..} cg = (nextState, out)
+syncT SyncAcquired3A{..} cg = nextState
  where
   nextState
     | not (isValidDw dw) = SyncAcquired4 cg rd dw rxEven
@@ -258,11 +228,8 @@ syncT self@SyncAcquired3A{..} cg = (nextState, out)
 
   (rd, dw) = ebTbDecode _rd cg
   rxEven = nextEven _rxEven
-  syncStatus = Ok
   goodCgs = _goodCgs + 1
-
-  out = (self, _cg, _rd, _dw, rxEven, syncStatus)
-syncT self@SyncAcquired4{..} cg = (nextState, out)
+syncT SyncAcquired4{..} cg = nextState
  where
   nextState
     | not (isValidDw dw) = LossOfSync cg rd dw rxEven
@@ -273,11 +240,8 @@ syncT self@SyncAcquired4{..} cg = (nextState, out)
 
   (rd, dw) = ebTbDecode _rd cg
   rxEven = nextEven _rxEven
-  syncStatus = Ok
   goodCgs = 0
-
-  out = (self, _cg, _rd, _dw, rxEven, syncStatus)
-syncT self@SyncAcquired4A{..} cg = (nextState, out)
+syncT SyncAcquired4A{..} cg = nextState
  where
   nextState
     | not (isValidDw dw) = LossOfSync cg rd dw rxEven
@@ -292,10 +256,31 @@ syncT self@SyncAcquired4A{..} cg = (nextState, out)
 
   (rd, dw) = ebTbDecode _rd cg
   rxEven = nextEven _rxEven
-  syncStatus = Ok
   goodCgs = _goodCgs + 1
 
-  out = (self, _cg, _rd, _dw, rxEven, syncStatus)
+-- | Output function for 'sync'. Takes the state as defined in 'SyncState' and
+--   returns a tuple containing the outputs as defined in Clause 36 of IEEE
+--   802.3
+syncO ::
+  -- | Current state
+  SyncState ->
+  -- | New state and output tuple
+  (SyncState, BitVector 10, Bool, DataWord, Even, SyncStatus)
+syncO self@LossOfSync{..} = (self, _cg, _rd, _dw, rxEven, Fail)
+ where
+  rxEven = nextEven _rxEven
+syncO self@CommaDetect1{..} = (self, _cg, _rd, _dw, Even, Fail)
+syncO self@AcquireSync1{..} = (self, _cg, _rd, _dw, rxEven, Fail)
+ where
+  rxEven = nextEven _rxEven
+syncO self@CommaDetect2{..} = (self, _cg, _rd, _dw, Even, Fail)
+syncO self@AcquireSync2{..} = (self, _cg, _rd, _dw, rxEven, Fail)
+ where
+  rxEven = nextEven _rxEven
+syncO self@CommaDetect3{..} = (self, _cg, _rd, _dw, Even, Fail)
+syncO self = (self, self._cg, self._rd, self._dw, rxEven, Ok)
+ where
+  rxEven = nextEven self._rxEven
 
 -- | Transition function for the inputs of 'Sgmii.pcsReceive'. This is used to
 --   keep a small list of "future" values for 'DataWord', such that these can
@@ -342,4 +327,4 @@ sync cg1 = out
       $ bundle (cg2, rd, dw, rxEven, syncStatus)
 
   (_, cg2, rd, dw, rxEven, syncStatus) =
-    mealyB syncT (LossOfSync 0 False (Dw 0) Even) cg1
+    mooreB syncT syncO (LossOfSync 0 False (Dw 0) Even) cg1

clash-cores/test/Test/Cores/Sgmii/Sgmii.hs

@@ -50,14 +50,14 @@ syncSim ::
   SyncState ->
   C.Signal dom (C.BitVector 10) ->
   C.Signal dom (C.BitVector 10, Bool, C.Vec 3 DataWord, Even, SyncStatus)
-syncSim s i = o
+syncSim s cg1 = o
  where
   o =
     C.moore outputQueueT outputQueueO (C.repeat (0, False, Dw 0, Odd, Ok)) $
-      C.bundle (cg, rd, dw, rxEven, syncStatus)
+      C.bundle (cg2, rd, dw, rxEven, syncStatus)
 
-  (_, cg, rd, dw, rxEven, syncStatus) =
-    C.mealyB syncT s i
+  (_, cg2, rd, dw, rxEven, syncStatus) =
+    C.mooreB syncT syncO s cg1
 
 -- | Version of 'pcsReceive' that allows the initial state to be set via an
 --   input variable