wrpll: add test to compare collector+filter against Matlab simulation

artiq/gateware/drtio/wrpll/core.py

@@ -1,3 +1,5 @@
+import numpy as np
+
 from migen import *
 from migen.genlib.resetsync import AsyncResetSynchronizer
 from migen.genlib.cdc import MultiReg, PulseSynchronizer
@@ -148,3 +150,88 @@ class WRPLL(Module, AutoCSR):
             self.main_dcxo.adpll_stb.eq(self.filter_main.output_stb),
             self.main_dcxo.adpll.eq(self.filter_main.output + self.adpll_offset_main.storage)
         ]
+
+
+def helper_sim(N=15):
+    class WRPLL(Module):
+        def __init__(self, N):
+            self.tag_ref = Signal(N)
+            self.input_stb = Signal()
+            self.adpll = Signal((24, True))
+            self.out_stb = Signal()
+
+            # # # #
+            loop_filter = thls.make(filters.helper, data_width=48)
+            self.submodules.loop_filter = loop_filter
+            self.submodules.collector = collector = Collector(N)
+
+            self.comb += [
+                self.collector.tag_ref.eq(self.tag_ref),
+                self.collector.ref_stb.eq(self.input_stb),
+                self.collector.main_stb.eq(self.input_stb),
+                self.loop_filter.input.eq(self.collector.out_helper << 22),
+                self.loop_filter.input_stb.eq(self.collector.out_stb),
+                self.adpll.eq(self.loop_filter.output),
+                self.out_stb.eq(self.loop_filter.output_stb),
+            ]
+    pll = WRPLL(N=N)
+
+    # check filter against output from MatLab model
+    initial_helper_out = -8000
+    ref_tags = np.array([
+       24778, 16789,  8801,   814, 25596, 17612,  9628,  1646,
+       26433, 18453, 10474,  2496, 27287, 19311, 11337,  3364, 28160,
+       20190, 12221,  4253, 29054, 21088, 13124,  5161, 29966, 22005,
+       14045,  6087, 30897, 22940, 14985,  7031, 31847, 23895, 15944,
+        7995,    47, 24869, 16923,  8978,  1035, 25861, 17920,  9981,
+        2042, 26873, 18937, 11002,  3069, 27904, 19973, 12042,  4113,
+       28953, 21026, 13100,  5175, 30020, 22098, 14177,  6257, 31106,
+       23189, 15273,  7358, 32212, 24300, 16388,  8478,   569, 25429,
+       17522,  9617,  1712, 26577, 18675, 10774,  2875, 27745, 19848,
+       11951,  4056, 28930, 21038, 13147,  5256, 30135, 22247, 14361,
+        6475, 31359, 23476, 15595,  7714, 32603, 24725, 16847,  8971,
+        1096
+    ])
+    adpll_sim = np.array([
+          8,   24,   41,   57,   74,   91,  107,  124,  140,  157,  173,
+        190,  206,  223,  239,  256,  273,  289,  306,  322,  339,  355,
+        372,  388,  405,  421,  438,  454,  471,  487,  504,  520,  537,
+        553,  570,  586,  603,  619,  636,  652,  668,  685,  701,  718,
+        734,  751,  767,  784,  800,  817,  833,  850,  866,  882,  899,
+        915,  932,  948,  965,  981,  998, 1014, 1030, 1047, 1063, 1080,
+       1096, 1112, 1129, 1145, 1162, 1178, 1194, 1211, 1227, 1244, 1260,
+       1276, 1293, 1309, 1326, 1342, 1358, 1375, 1391, 1407, 1424, 1440,
+       1457, 1473, 1489, 1506, 1522, 1538, 1555, 1571, 1587, 1604, 1620,
+       1636])
+
+    def sim():
+        yield pll.collector.out_helper.eq(initial_helper_out)
+        for ref_tag, adpll_matlab in zip(ref_tags, adpll_sim):
+            # feed collector
+            yield pll.tag_ref.eq(int(ref_tag))
+            yield pll.input_stb.eq(1)
+
+            yield
+
+            yield pll.input_stb.eq(0)
+
+            while not (yield pll.collector.out_stb):
+                yield
+
+            tag_diff = yield pll.collector.out_helper
+
+            while not (yield pll.loop_filter.output_stb):
+                yield
+
+            adpll_migen = yield pll.adpll
+            print("ref tag diff: {}, migen sim adpll {}, matlab adpll {}"
+                  .format(tag_diff, adpll_migen, adpll_matlab))
+
+            assert adpll_migen == adpll_matlab
+            yield
+
+    run_simulation(pll, [sim()])
+
+
+if __name__ == "__main__":
+    helper_sim()