1 files changed, 72 insertions, 0 deletions
diff --git a/zephyr/zmake/zmake/toolchains.py b/zephyr/zmake/zmake/toolchains.py
new file mode 100644
index 0000000000..1ef79f6849
--- /dev/null
+++ b/zephyr/zmake/zmake/toolchains.py
@@ -0,0 +1,72 @@
+# Copyright 2020 The Chromium OS Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+"""Definitions of toolchain variables."""
+
+import glob
+import os
+import pathlib
+
+import zmake.build_config as build_config
+
+
+def find_zephyr_sdk():
+    """Find the Zephyr SDK, if it's installed.
+
+    Returns:
+        The path to the Zephyr SDK, using the search rules defined by
+        https://docs.zephyrproject.org/latest/getting_started/installation_linux.html
+    """
+    def _gen_sdk_paths():
+        yield os.getenv('ZEPHYR_SDK_INSTALL_DIR')
+
+        for searchpath in ('~/zephyr-sdk', '~/.local/zephyr-sdk',
+                           '~/.local/opt/zephyr-sdk', '~/bin/zephyr-sdk',
+                           '/opt/zephyr-sdk', '/usr/zephyr-sdk',
+                           '/usr/local/zephyr-sdk'):
+            for suffix in ('', '-*'):
+                yield from glob.glob(os.path.expanduser(searchpath + suffix))
+
+    for path in _gen_sdk_paths():
+        if not path:
+            continue
+        path = pathlib.Path(path)
+        if (path / 'sdk_version').is_file():
+            return path
+
+    raise OSError('Unable to find the Zephyr SDK')
+
+
+# Mapping of toolchain names -> (λ (module-paths) build-config)
+toolchains = {
+    'coreboot-sdk': lambda modules: build_config.BuildConfig(
+        cmake_defs={'TOOLCHAIN_ROOT': str(modules['zephyr-chrome']),
+                    'ZEPHYR_TOOLCHAIN_VARIANT': 'coreboot-sdk'}),
+    'llvm': lambda modules: build_config.BuildConfig(
+        cmake_defs={'TOOLCHAIN_ROOT': str(modules['zephyr-chrome']),
+                    'ZEPHYR_TOOLCHAIN_VARIANT': 'llvm'}),
+    'zephyr': lambda _: build_config.BuildConfig(
+        cmake_defs={'ZEPHYR_TOOLCHAIN_VARIANT': 'zephyr',
+                    'ZEPHYR_SDK_INSTALL_DIR': str(find_zephyr_sdk())}),
+    'arm-none-eabi': lambda _: build_config.BuildConfig(
+        cmake_defs={'ZEPHYR_TOOLCHAIN_VARIANT': 'cross-compile',
+                    'CROSS_COMPILE': '/usr/bin/arm-none-eabi-'}),
+}
+
+
+def get_toolchain(name, module_paths):
+    """Get a toolchain by name.
+
+    Args:
+        name: The name of the toolchain.
+        module_paths: Dictionary mapping module names to paths.
+
+    Returns:
+        The corresponding BuildConfig from the defined toolchains, if
+        one exists, otherwise a simple BuildConfig which sets
+        ZEPHYR_TOOLCHAIN_VARIANT to the corresponding name.
+    """
+    if name in toolchains:
+        return toolchains[name](module_paths)
+    return build_config.BuildConfig(
+        cmake_defs={'ZEPHYR_TOOLCHAIN_VARIANT': name})