[µTVM] Add support for mps2_an521 board

apps/microtvm/zephyr/demo_runtime/boards/mps2_an521.conf

@@ -0,0 +1,28 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+#
+# This file is specific to the MPS2-AN512 board.
+
+# For intrinsics used by generated optimized operators.
+CONFIG_CMSIS_DSP=y
+
+# For random number generation.
+CONFIG_ENTROPY_GENERATOR=y
+CONFIG_TEST_RANDOM_GENERATOR=y
+
+# For debugging.
+CONFIG_LED=n

apps/microtvm/zephyr/demo_runtime/qemu-hack/qemu-system-arm

@@ -0,0 +1 @@
+./qemu-system-i386

python/tvm/micro/contrib/zephyr.py

@@ -108,7 +108,17 @@ def __init__(
                 f"project_dir supplied to ZephyrCompiler does not exist: {project_dir}"
             )
 
+        self._qemu = "qemu" in board
+
+        # For Zephyr boards that run emulated by default but don't have the prefix "qemu_" in their
+        # board names, a suffix "-qemu" is added by users of µTVM when specifying the board name to
+        # inform that the QEMU transporter must be used just like for the boards with the prefix.
+        # Zephyr does not recognize the suffix, so we trim it off before passing it.
+        if "-qemu" in board:
+            board = board.replace("-qemu", "")
+
         self._board = board
+
         if west_cmd is None:
             self._west_cmd = [sys.executable, "-mwest.app.main"]
         elif isinstance(west_cmd, str):
@@ -257,14 +267,17 @@ def binary(self, output, objects, options=None, link_main=True, main_options=Non
                 "cmake_cache": ["CMakeCache.txt"],
                 "device_tree": [os.path.join("zephyr", "zephyr.dts")],
             },
-            immobile="qemu" in self._board,
+            immobile=bool(self._qemu),
         )
 
     @property
     def flasher_factory(self):
         return compiler.FlasherFactory(
             ZephyrFlasher,
-            (self._board,),
+            (
+                self._board,
+                self._qemu,
+            ),
             dict(
                 zephyr_base=self._zephyr_base,
                 project_dir=self._project_dir,
@@ -316,6 +329,7 @@ class ZephyrFlasher(tvm.micro.compiler.Flasher):
     def __init__(
         self,
         board,
+        qemu,
         zephyr_base=None,
         project_dir=None,
         subprocess_env=None,
@@ -336,6 +350,7 @@ def __init__(
             sys.path.pop(0)
 
         self._board = board
+        self._qemu = qemu
         self._zephyr_base = zephyr_base
         self._project_dir = project_dir
         self._west_cmd = west_cmd
@@ -447,10 +462,7 @@ def _zephyr_transport(self, micro_binary):
         )
 
     def flash(self, micro_binary):
-        cmake_entries = read_cmake_cache(
-            micro_binary.abspath(micro_binary.labelled_files["cmake_cache"][0])
-        )
-        if "qemu" in cmake_entries["BOARD"]:
+        if self._qemu:
             return self._zephyr_transport(micro_binary)
 
         build_dir = os.path.dirname(

python/tvm/target/target.py

@@ -278,6 +278,7 @@ def intel_graphics(model="unknown", options=None):
     "host": [],
     "stm32f746xx": ["-mcpu=cortex-m7", "-march=armv7e-m"],
     "nrf5340dk": ["-mcpu=cortex-m33"],
+    "mps2_an521": ["-mcpu=cortex-m33"],
 }
 
 

tests/lint/check_file_type.py

@@ -137,7 +137,9 @@
     "apps/microtvm/zephyr/demo_runtime/boards/nrf5340dk_nrf5340_cpuapp.conf",
     "apps/microtvm/zephyr/demo_runtime/boards/nucleo_f746zg.conf",
     "apps/microtvm/zephyr/demo_runtime/boards/stm32f746g_disco.conf",
+    "apps/microtvm/zephyr/demo_runtime/boards/mps2_an521.conf",
     "apps/microtvm/zephyr/demo_runtime/qemu-hack/qemu-system-i386",
+    "apps/microtvm/zephyr/demo_runtime/qemu-hack/qemu-system-arm",
     "apps/microtvm/zephyr/demo_runtime/qemu-hack/qemu-system-riscv32",
     "apps/microtvm/zephyr/demo_runtime/qemu-hack/qemu-system-riscv64",
     # microTVM Virtual Machines

tutorials/micro/micro_tflite.py

@@ -174,25 +174,33 @@
 # Defining the target
 # -------------------
 #
-# Now we create a build config for relay. turning off two options
-# and then calling relay.build which will result in a C source
-# file. When running on a simulated target, choose "host" below:
-# TARGET = tvm.target.target.micro("host")
-
-# %%
-# Compiling for physical hardware
-#  When running on physical hardware, choose a target and a board that
-#  describe the hardware. The STM32F746 Nucleo target and board is chosen in
-#  this commented code. Another option would be to choose the same target but
-#  the STM32F746 Discovery board instead. The disco board has the same
-#  microcontroller as the Nucleo board but a couple of wirings and configs
-#  differ, so it's necessary to select the "stm32f746g_disco" board below.
-#
-#  .. code-block:: python
+# Now we create a build config for relay, turning off two options and then calling relay.build which
+# will result in a C source file for the selected TARGET. When running on a simulated target of the
+# same architecture as the host (where this Python script is executed) choose "host" below for the
+# TARGET and a proper board/VM to run it (Zephyr will create the right QEMU VM based on BOARD. In
+# the example below the x86 arch is selected and a x86 VM is picked up accordingly:
 #
 TARGET = tvm.target.target.micro("host")
-# BOARD = "nucleo_f746zg" # or "stm32f746g_disco"
 BOARD = "qemu_x86"
+#
+# Compiling for physical hardware
+#  When running on physical hardware, choose a TARGET and a BOARD that describe the hardware. The
+#  STM32F746 Nucleo target and board is chosen in the example below. Another option would be to
+#  choose the STM32F746 Discovery board instead. Since that board has the same MCU as the Nucleo
+#  board but a couple of wirings and configs differ, it's necessary to select the "stm32f746g_disco"
+#  board to generated the right firmware image.
+#
+#  TARGET = tvm.target.target.micro("stm32f746xx")
+#  BOARD = "nucleo_f746zg" # or "stm32f746g_disco#"
+#
+#  For some boards, Zephyr runs them emulated by default, using QEMU. For example, below is the
+#  TARGET and BOARD used to build a microTVM firmware for the mps2-an521 board. Since that board
+#  runs emulated by default on Zephyr the suffix "-qemu" is added to the board name to inform
+#  microTVM that the QEMU transporter must be used to communicate with the board. If the board name
+#  already has the prefix "qemu_", like "qemu_x86", then it's not necessary to add that suffix.
+#
+#  TARGET = tvm.target.target.micro("mps2_an521")
+#  BOARD = "mps2_an521-qemu"
 
 ######################################################################
 # Now, compile the model for the target:
@@ -203,9 +211,8 @@
     graph, c_mod, c_params = relay.build(mod, target=TARGET, params=params)
 
 
-# %%
-# Compiling for a simulated device
-# --------------------------------
+# Compiling for a host simulated device
+# -------------------------------------
 #
 # First, compile a static microTVM runtime for the targeted device. In this case, the host simulated
 # device is used.
@@ -214,11 +221,10 @@
     os.path.join(tvm.micro.get_standalone_crt_dir(), "template", "host")
 )
 
-# %%
-# Compiling for physical hardware
-#  For physical hardware, comment out the previous section and use this compiler definition instead.
-#
-#  .. code-block:: python
+# Compiling for physical hardware (or an emulated board, like the mps_an521)
+# --------------------------------------------------------------------------
+#  For physical hardware, comment out the previous section selecting TARGET and BOARD and use this
+#  compiler definition instead of the one above.
 #
 #     import subprocess
 #     from tvm.micro.contrib import zephyr
@@ -227,15 +233,15 @@
 #     project_dir = os.path.join(repo_root, "apps", "microtvm", "zephyr", "demo_runtime")
 #     compiler = zephyr.ZephyrCompiler(
 #         project_dir=project_dir,
-#         board=BOARD if "stm32f746" in str(TARGET) else "qemu_x86",
+#         board=BOARD,
 #         zephyr_toolchain_variant="zephyr",
 #     )
 #
 #     opts = tvm.micro.default_options(f"{project_dir}/crt")
 #
-# enable printing memory usage statistics of the runtime image
-# generated by Zephyr compiler for the physical hardware
-# logging.basicConfig(level="INFO")
+#
+#     # Enable printing memory usage statistics for the runtime image generated by Zephyr
+#     logging.basicConfig(level="INFO")
 
 workspace = tvm.micro.Workspace()
 micro_binary = tvm.micro.build_static_runtime(