[Test] introduce new test for external weights

tests/end2end/test_ext_weights.py

+# Copyright (c) 2021, Xilinx
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+#
+# * Redistributions of source code must retain the above copyright notice, this
+#   list of conditions and the following disclaimer.
+#
+# * Redistributions in binary form must reproduce the above copyright notice,
+#   this list of conditions and the following disclaimer in the documentation
+#   and/or other materials provided with the distribution.
+#
+# * Neither the name of FINN nor the names of its
+#   contributors may be used to endorse or promote products derived from
+#   this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+import torch
+from brevitas.nn import QuantLinear, QuantReLU
+import torch.nn as nn
+import numpy as np
+from brevitas.core.quant import QuantType
+from brevitas.nn import QuantIdentity
+import brevitas.onnx as bo
+from finn.core.modelwrapper import ModelWrapper
+from finn.core.datatype import DataType
+import finn.builder.build_dataflow as build
+import finn.builder.build_dataflow_config as build_cfg
+import os
+import shutil
+from finn.util.test import get_build_env, load_test_checkpoint_or_skip
+import pytest
+from finn.util.basic import make_build_dir
+import pkg_resources as pk
+import json
+import wget
+import subprocess
+
+target_clk_ns = 10
+build_kind = "zynq"
+build_dir = os.environ["FINN_BUILD_DIR"]
+onnx_zip_url = "https://github.com/Xilinx/finn-examples/releases/download/v0.0.1a/onnx-models-bnn-pynq.zip"
+onnx_zip_local = build_dir + "/onnx-models-bnn-pynq.zip"
+
+def get_checkpoint_name(step):
+    if step == "build":
+        # checkpoint for build step is an entire dir
+        return build_dir + "/end2end_ext_weights_build"
+    else:
+        # other checkpoints are onnx files
+        return build_dir + "/end2end_ext_weights_%s.onnx" % (step)
+
+
+def test_end2end_ext_weights_download():
+    if not os.path.isfile(onnx_zip_local):
+        wget.download(onnx_zip_url, out=onnx_zip_local)
+    assert os.path.isfile(onnx_zip_local)
+    subprocess.check_output(['unzip', onnx_zip_local])