pipeline GW: refactor byte2word & cleanup

src/gateware/cxp_pipeline.py

@@ -3,6 +3,9 @@ from misoc.interconnect.csr import *
 from misoc.interconnect import stream
 from misoc.cores.liteeth_mini.mac.crc import LiteEthMACCRCEngine, LiteEthMACCRCChecker
 
+
+import struct
+
 upconn_dw = 8
 upconn_layout = [("data", upconn_dw), ("k", upconn_dw//8)]
 
@@ -22,12 +25,11 @@ KCode = {
 }
 
 
-def _bytes2word(arr):
-    assert len(arr) == 4
-    sum = 0
-    for i, val in enumerate(arr):
-        sum += (val & 0xFF) << i*8
-    return sum 
+def _bytes2word(bytes, big_endian=True):
+    if big_endian:
+        return struct.unpack(">I", struct.pack(">4B", *bytes))[0]
+    else:
+        return struct.unpack("<I", struct.pack(">4B", *bytes))[0]
 
 class Code_Source(Module):
     def __init__(self, layout, counts=4):
@@ -390,6 +392,8 @@ class Receiver_Path(Module, AutoCSR):
 
         # TODO:
         self.packet_type = Signal(8)
+        self.decoder_err = Signal()
+        self.decoder_err_clr = Signal()
 
         # # #
 
@@ -398,10 +402,19 @@ class Receiver_Path(Module, AutoCSR):
         self.submodules.packet_decoder = packet_decoder = CXP_Data_Packet_Decode()
         self.sync += [
             If(trig_ack_checker.ack,
-               self.trig_ack.eq(1),
+                self.trig_ack.eq(1),
             ).Elif(self.trig_clr,
-               self.trig_ack.eq(0),
+                self.trig_ack.eq(0),
+            ),
+
+            If(packet_decoder.decode_err,
+                self.decoder_err.eq(1),
+            ).Elif(self.decoder_err_clr,
+                self.decoder_err.eq(0),
             )
+        ]
+        self.comb += [
+            self.packet_type.eq(packet_decoder.packet_type),
             
         ]
 
@@ -465,11 +478,11 @@ class CXP_Data_Packet_Decode(Module):
             ).Elif(self.packet_type == type["debug"],
                 self.sink.connect(self.source),
             ).Else(
-                # discard K29,7
                 self.sink.ack.eq(1),
-                NextValue(self.decode_err, 1),
+                self.decode_err.eq(1),
             )
         )
+
 class CXP_Trig_Ack_Checker(Module, AutoCSR):
     def __init__(self):
         self.sink = stream.Endpoint(downconn_layout)