From 26d940fbc32c0b23395804b7240fe943436aa313 Mon Sep 17 00:00:00 2001
From: morgan <mc@m-labs.hk>
Date: Tue, 14 Jan 2025 10:46:01 +0800
Subject: [PATCH] frameline GW: remove eop marker

---
 src/gateware/cxp_frame_pipeline.py | 62 ++++--------------------------
 1 file changed, 7 insertions(+), 55 deletions(-)

diff --git a/src/gateware/cxp_frame_pipeline.py b/src/gateware/cxp_frame_pipeline.py
index 3447f9d..82116f3 100644
--- a/src/gateware/cxp_frame_pipeline.py
+++ b/src/gateware/cxp_frame_pipeline.py
@@ -21,27 +21,6 @@ def switch_endianness(s):
     char = [s[i*8:(i+1)*8] for i in range(len(s)//8)]
     return Cat(char[::-1])
 
-class EOP_Inserter(Module):
-    def __init__(self):
-        self.sink = stream.Endpoint(word_layout_dchar)
-        self.source = stream.Endpoint(word_layout_dchar)
-
-        # # #
-
-        self.sync += [
-            If((~self.source.stb | self.source.ack),
-                If(~((self.sink.dchar == KCode["pak_end"]) & (self.sink.dchar_k == 1)),
-                    self.sink.connect(self.source, omit={"ack", "eop"}),
-                ).Else(
-                    self.source.stb.eq(0),
-                )
-            ),
-        ]
-        self.comb += [
-            self.sink.ack.eq(~self.source.stb | self.source.ack),
-            self.source.eop.eq(((self.sink.dchar == KCode["pak_end"]) & (self.sink.dchar_k == 1))),
-        ]
-
 class End_Of_Line_Inserter(Module):
     def __init__(self):
         self.l_size = Signal(3*char_width)
@@ -76,26 +55,6 @@ class End_Of_Line_Inserter(Module):
             self.source.eop.eq(cnt == 1),
         ]
 
-class EOP_Marker(Module):
-    def __init__(self):
-        self.sink = stream.Endpoint(word_layout_dchar)
-        self.source = stream.Endpoint(word_layout_dchar)
-
-        # # #
-
-        last_stb = Signal()
-        self.sync += [
-            If((~self.source.stb | self.source.ack),
-                self.source.stb.eq(self.sink.stb),
-                self.source.payload.eq(self.sink.payload),
-            ),
-            last_stb.eq(self.sink.stb),
-        ]
-        self.comb += [
-            self.sink.ack.eq(~self.source.stb | self.source.ack),
-            self.source.eop.eq(~self.sink.stb & last_stb),
-        ]
-
 class Stream_Arbiter(Module):
     def __init__(self, n_downconn):
         self.n_ext_active = Signal(max=n_downconn) 
@@ -657,11 +616,11 @@ class Frame_Packet_Router(Module):
 
         # # #
         
-        #                  +----------+     +-------------+
-        # eop marker ----->|          |     |             |------> crc checker 
-        #                  | arbiter  |---->| broadcaster |
-        # eop marker ----->| need eop |     |             |------> crc checker 
-        #                  +----------+     +-------------+
+        #                  +---------+     +-------------+
+        # rx pipline ----->|         |     |             |------> crc checker ------> raw stream data 
+        #                  | arbiter |---->| broadcaster |
+        # rx pipline ----->|         |     |             |------> crc checker ------> raw stream data 
+        #                  +---------+     +-------------+
         #
 
         self.submodules.arbiter = arbiter = Stream_Arbiter(n_downconn)
@@ -672,15 +631,8 @@ class Frame_Packet_Router(Module):
             self.sync += broadcaster.routing_table[i].eq(s)
 
         for i, d in enumerate(downconns):
-            # eop is needed for arbiter and crc checker to work correctly
-            # TODO: move eop inserter inside of broadcaster
-            # TODO: change arbiter to use K27.7 as eop instead
-            eop_marker = EOP_Inserter()
-            self.submodules += eop_marker
-            self.comb += [
-                d.source.connect(eop_marker.sink),
-                eop_marker.source.connect(arbiter.sinks[i])
-            ]
+            # Assume downconns pipeline already marks the eop
+            self.comb += d.source.connect(arbiter.sinks[i])
 
         self.comb += arbiter.source.connect(broadcaster.sink)