[Test] fix test_split_large_fifos, include pow2 behavior

tests/fpgadataflow/test_split_large_fifos.py

@@ -32,10 +32,12 @@ import pytest
 import json
 import shutil
 from brevitas.export.onnx.generic.manager import BrevitasONNXManager
-from math import ceil
+from qonnx.core.modelwrapper import ModelWrapper
+from qonnx.custom_op.registry import getCustomOp
 
 import finn.builder.build_dataflow as build
 import finn.builder.build_dataflow_config as build_cfg
+from finn.transformation.fpgadataflow.set_fifo_depths import get_fifo_split_configs
 from finn.util.basic import make_build_dir
 from finn.util.test import get_trained_network_and_ishape
 
@@ -53,7 +55,7 @@ def get_folding_cfg(depth=65536):
     cfg["Defaults"] = dict()
     for i in range(3):
         key = "StreamingFIFO_" + str(i)
-        cfg[key] = {"depth": depth, "ram_style": "auto", "impl_style": "rtl"}
+        cfg[key] = {"depth": depth, "ram_style": "auto", "impl_style": "vivado"}
     return cfg
 
 
@@ -93,12 +95,32 @@ def test_split_large_fifos(depth):
         / float(est_data["estimated_throughput_fps"])
         > 0.9
     )
-    with open(tmp_output_dir + "/final_hw_config.json") as f:
-        hw_config = json.load(f)
-    n = 0
-    for key in hw_config:
-        if "StreamingFIFO" in key:
-            n += 1
-    assert n == 3 * ceil(depth / 32768) + 1
+    model = ModelWrapper(
+        tmp_output_dir + "/intermediate_models/step_set_fifo_depths.onnx"
+    )
+    # exclude final FIFO node (output FIFO, not part of test)
+    fifo_nodes = model.get_nodes_by_op_type("StreamingFIFO")[:-1]
+    golden_cfg = get_fifo_split_configs(depth, 256, 32768)
+    for i, fifo_node in enumerate(fifo_nodes):
+        inst = getCustomOp(fifo_node)
+        fifo_depth = inst.get_nodeattr("depth")
+        assert fifo_depth == golden_cfg[i % len(golden_cfg)][0]
 
     shutil.rmtree(tmp_output_dir)
+
+
+def test_split_large_fifo_configs():
+    ret0 = get_fifo_split_configs(513, 256, 32768)
+    assert ret0 == [(512, "vivado"), (1, "rtl")]
+    ret1 = get_fifo_split_configs(1200, 256, 32768)
+    assert ret1 == [(1024, "vivado"), (176, "rtl")]
+    ret2 = get_fifo_split_configs(45000, 256, 32768)
+    assert ret2 == [
+        (32768, "vivado"),
+        (8192, "vivado"),
+        (2048, "vivado"),
+        (1024, "vivado"),
+        (512, "vivado"),
+        (256, "rtl"),
+        (200, "rtl"),
+    ]