Add ASF headers and split host uTVM API defs

Author: weberlo

src/runtime/micro/device/arm/stm32f746xx/utvm_init.s

@@ -16,6 +16,13 @@
  * specific language governing permissions and limitations
  * under the License.
  */
+
+/*!
+ *  Copyright (c) 2019 by Contributors
+ * \file utvm_init.s
+ * \brief uTVM init definition for STM32F746XX-series boards
+ */
+
 .syntax unified
 .cpu cortex-m7
 .fpu softvfp

src/runtime/micro/device/arm/stm32f746xx/utvm_timer.c

@@ -1,3 +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.
+ */
+
+/*!
+ *  Copyright (c) 2019 by Contributors
+ * \file utvm_timer.c
+ * \brief uTVM timer API definitions for STM32F746XX-series boards
+ */
+
 #ifdef __cplusplus
 extern "C" {
 #endif

src/runtime/micro/device/host/utvm_init.c

@@ -0,0 +1,39 @@
+/*
+ * 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.
+ */
+
+/*!
+ *  Copyright (c) 2019 by Contributors
+ * \file utvm_init.c
+ * \brief uTVM init definition for the host emulated device
+ */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "utvm_runtime.h"
+
+void UTVMInit() {
+  // no init required for the host
+  UTVMMain();
+}
+
+#ifdef __cplusplus
+}  // TVM_EXTERN_C
+#endif

src/runtime/micro/device/host/utvm_timer.c

@@ -1,3 +1,27 @@
+/*
+ * 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.
+ */
+
+/*!
+ *  Copyright (c) 2019 by Contributors
+ * \file utvm_timer.c
+ * \brief uTVM timer API stubs for the host emulated device
+ */
 
 #ifdef __cplusplus
 extern "C" {
@@ -7,10 +31,6 @@ extern "C" {
 
 // TODO(weberlo): use this? https://stackoverflow.com/questions/5141960/get-the-current-time-in-c
 
-void UTVMInit() {
-  UTVMMain();
-}
-
 int32_t UTVMTimerStart() {
   return 0;
 }

src/runtime/micro/host_driven/utvm_runtime.c

@@ -22,9 +22,9 @@
  * \file utvm_runtime.cc
  * \brief uTVM runtime
  *
- * All function calls go through `UTVMMain`, which reads from the current
- * `UTVMTask` and calls the appropriate function with the arguments from the
- * task.
+ * All function calls go through the externally defined `UTVMInit`, which
+ * performs device-specific setup, then calls `UTVMMain`.  `UTVMMain` then
+ * calls the function in `utvm_task` with the arguments from the task.
  *
  * Additionally included in this file are definitions for some of the most
  * common functions used in the C runtime API.