analyzer: fix endianness issue

src/gateware/analyzer.py

@@ -7,6 +7,15 @@ from migen_axi.interconnect import axi
 from artiq.gateware.rtio.analyzer import message_len, MessageEncoder
 
 
+def convert_endianness(signal):
+    assert len(signal) % 8 == 0
+    nbytes = len(signal)//8
+    signal_bytes = []
+    for i in range(nbytes):
+        signal_bytes.append(signal[8*i:8*(i+1)])
+    return Cat(*reversed(signal_bytes))
+
+
 class AXIDMAWriter(Module, AutoCSR):
     def __init__(self, membus, max_outstanding_requests):
         aw = len(membus.aw.addr)
@@ -55,7 +64,7 @@ class AXIDMAWriter(Module, AutoCSR):
             membus.w.id.eq(0),
             membus.w.valid.eq(self.sink.stb),
             self.sink.ack.eq(membus.w.ready),
-            membus.w.data.eq(self.sink.data),
+            membus.w.data.eq(convert_endianness(self.sink.data)),
             membus.w.strb.eq(2**(dw//8)-1),
         ]
         beat_count = Signal(max=burst_length)