Clock: Inherit the clock from parent by default

This patch changes the default 1 Tick clock period to a proxy that
resolves the parents clock. As a result of this, the caches and
L1-to-L2 bus, for example, will automatically use the clock period of
the CPU unless explicitly overridden.

To ensure backwards compatibility, the System class overrides the
proxy and specifies a 1 Tick clock. We could change this to something
more reasonable in a follow-on patch, perhaps 1 GHz or something
similar.

With this patch applied, all clocked objects should have a reasonable
clock period set, and could start specifying delays in Cycles instead
of absolute time.

1 files changed, 5 insertions, 1 deletions

diff --git a/src/sim/ClockedObject.py b/src/sim/ClockedObject.py
index 9bb243df8..26b0e2348 100644
--- a/src/sim/ClockedObject.py
+++ b/src/sim/ClockedObject.py
@@ -37,9 +37,13 @@
 
 from m5.SimObject import SimObject
 from m5.params import *
+from m5.proxy import *
 
 class ClockedObject(SimObject):
     type = 'ClockedObject'
     abstract = True
 
-    clock = Param.Clock('1t', "Clock speed")
+    # Clock period of this object, with the default value being the
+    # clock period of the parent object, unproxied at instantiation
+    # time
+    clock = Param.Clock(Parent.clock, "Clock speed")