drtio: basic RT packet echo test

artiq/test/gateware/drtio/test_rt_packets.py

@@ -0,0 +1,67 @@
+import unittest
+
+from migen import *
+
+from artiq.gateware.drtio.rt_packets import *
+
+
+class PacketInterface:
+    def __init__(self, direction, frame, data):
+        if direction == "m2s":
+            self.plm = get_m2s_layouts(len(data))
+        elif direction == "s2m":
+            self.plm = get_s2m_layouts(len(data))
+        else:
+            raise ValueError
+        self.frame = frame
+        self.data = data
+
+    def send(self, ty, **kwargs):
+        idx = 8
+        value = self.plm.types[ty]
+        for field_name, field_size in self.plm.layouts[ty][1:]:
+            try:
+                fvalue = kwargs[field_name]
+                del kwargs[field_name]
+            except KeyError:
+                fvalue = 0
+            value = value | (fvalue << idx)
+            idx += field_size
+        if kwargs:
+            raise ValueError
+
+        ws = len(self.data)
+        yield self.frame.eq(1)
+        for i in range(idx//ws):
+            yield self.data.eq(value)
+            value >>= ws
+            yield
+        yield self.frame.eq(0)
+        yield
+
+    @passive
+    def receive(self, callback):
+        previous_frame = 0
+        frame_words = []
+        while True:
+            frame = yield self.frame
+            if frame:
+                frame_words.append((yield self.data))
+            if previous_frame and not frame:
+                callback(frame_words)
+                frame_words = []
+            previous_frame = frame
+            yield
+
+
+class TestSatellite(unittest.TestCase):
+    def test_echo(self):
+        nwords = 4
+        dut = RTPacketSatellite(nwords)
+        pt = PacketInterface("m2s", dut.rx_rt_frame, dut.rx_rt_data)
+        pr = PacketInterface("s2m", dut.tx_rt_frame, dut.tx_rt_data)
+        def send():
+            yield from pt.send("echo_request")
+            for i in range(40):
+                yield
+        run_simulation(dut, [send(), pr.receive(print)])