Gem5: Add support for deploying the m5 binary

wlauto/common/gem5/LICENSE

@@ -0,0 +1,6 @@
+The gem5 simulator can be obtained from http://repo.gem5.org/gem5/ and the
+corresponding documentation can be found at http://www.gem5.org.
+
+The source for the m5 binaries bundled with Workload Automation (found at
+wlauto/common/bin/arm64/m5 and wlauto/common/bin/armeabi/m5) can be found at
+util/m5 in the gem5 source at http://repo.gem5.org/gem5/.

wlauto/common/gem5/device.py

@@ -29,6 +29,8 @@ import time
 from pexpect import EOF, TIMEOUT, pxssh
 
 from wlauto import settings, Parameter
+from wlauto.core.resource import NO_ONE
+from wlauto.common.resources import Executable
 from wlauto.core import signal as sig
 from wlauto.exceptions import DeviceError
 from wlauto.utils import ssh, types
@@ -112,6 +114,7 @@ class BaseGem5Device(object):
         self.gem5 = None
         self.gem5_port = -1
         self.gem5outdir = os.path.join(settings.output_directory, "gem5")
+        self.m5_path = 'm5'
         self.stdout_file = None
         self.stderr_file = None
         self.stderr_filename = None
@@ -609,7 +612,7 @@ class BaseGem5Device(object):
 
     def gem5_util(self, command):
         """ Execute a gem5 utility command using the m5 binary on the device """
-        self.gem5_shell('/sbin/m5 ' + command)
+        self.gem5_shell('{} {}'.format(self.m5_path, command))
 
     def sync_gem5_shell(self):
         """
@@ -666,3 +669,33 @@ class BaseGem5Device(object):
         mount_command = "mount -t 9p -o trans=virtio,version=9p2000.L,aname={} gem5 /mnt/obb".format(self.temp_dir)
         self.gem5_shell(mount_command)
 
+    def deploy_m5(self, context, force=False):
+        """
+        Deploys the m5 binary to the device and returns the path to the binary
+        on the device.
+
+        :param force: by default, if the binary is already present on the
+                    device, it will not be deployed again. Setting force to
+                    ``True`` overrides that behaviour and ensures that the
+                    binary is always copied. Defaults to ``False``.
+
+        :returns: The on-device path to the m5 binary.
+
+        """
+        on_device_executable = self.path.join(self.binaries_directory, 'm5')
+        if not force and self.file_exists(on_device_executable):
+            # We want to check the version of the binary. We cannot directly
+            # check this because the m5 binary itself is unversioned. We also
+            # need to make sure not to check the error code as "m5 --help"
+            # returns a non-zero error code.
+            output = self.gem5_shell('m5 --help', check_exit_code=False)
+            if "writefile" in output:
+                self.logger.debug("Using the m5 binary on the device...")
+                self.m5_path = on_device_executable
+                return on_device_executable
+            else:
+                self.logger.debug("m5 on device does not support writefile!")
+        host_file = context.resolver.get(Executable(NO_ONE, self.abi, 'm5'))
+        self.logger.info("Installing the m5 binary to the device...")
+        self.m5_path = self.install(host_file)
+        return self.m5_path

wlauto/devices/android/gem5/__init__.py

@@ -207,3 +207,4 @@ class Gem5AndroidDevice(BaseGem5Device, AndroidDevice):
 
     def initialize(self, context):
         self.resize_shell()
+        self.deploy_m5(context, force=False)

wlauto/devices/linux/gem5/__init__.py

@@ -111,3 +111,4 @@ class Gem5LinuxDevice(BaseGem5Device, LinuxDevice):
 
     def initialize(self, context):
         self.resize_shell()
+        self.deploy_m5(context, force=False)