scons: Make MOESI_CMP_directory the default ARM ruby protocol

Previously ARM binaries were by default compiled with the MI_example
protocol. The MI_example protocol cannot properly support load/store
exclusive instructions and therefore it cannot be used to simulate
multicore ARM systems. This change changes to MOESI_CMP_directory as
the default ruby protocol for ARM systems.

Change-Id: I942d950ba466aea9a75f3d8764f9f3eddd0c3baa
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/2906
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

build_opts/ARM

@@ -1,3 +1,3 @@
 TARGET_ISA = 'arm'
 CPU_MODELS = 'AtomicSimpleCPU,TimingSimpleCPU,O3CPU,MinorCPU'
-PROTOCOL = 'MI_example'
+PROTOCOL = 'MOESI_CMP_directory'

tests/testing/tests.py

@@ -1,6 +1,6 @@
 #!/usr/bin/env python2
 #
-# Copyright (c) 2016 ARM Limited
+# Copyright (c) 2016-2017 ARM Limited
 # All rights reserved
 #
 # The license below extends only to copyright in the software and shall
@@ -161,6 +161,16 @@ generic_configs = (
     'learning-gem5-p1-two-level',
 )
 
+default_ruby_protocol = {
+    "arm" : "MOESI_CMP_directory",
+}
+
+def get_default_protocol(arch):
+    try:
+        return default_ruby_protocol[arch]
+    except KeyError:
+        return 'MI-example'
+
 all_categories = ("quick", "long")
 all_modes = ("fs", "se")
 
@@ -337,8 +347,11 @@ def get_tests(isa,
     else:
         configs += generic_configs
 
-    if ruby_protocol == 'MI_example':
-        configs += [ "%s-ruby" % (c, ) for c in configs ]
+    if ruby_protocol == get_default_protocol(isa):
+        if ruby_protocol == 'MI_example':
+            configs += [ "%s-ruby" % (c, ) for c in configs ]
+        else:
+            configs += [ "%s-ruby-%s" % (c, ruby_protocol) for c in configs ]
     elif ruby_protocol is not None:
         # Override generic ISA configs when using Ruby (excluding
         # MI_example which is included in all ISAs by default). This