This patch moves the clock of the CPU, bus, and numerous devices to
the new class ClockedObject, that sits in between the SimObject and
MemObject in the class hierarchy. Although there are currently a fair
amount of MemObjects that do not make use of the clock, they
potentially should do so, e.g. the caches should at some point have
the same clock as the CPU, potentially with a 1:n ratio. This patch
does not introduce any new clock objects or object hierarchies
(clusters, clock domains etc), but is still a step in the direction of
having a more structured approach clock domains.
The most contentious part of this patch is the serialisation of clocks
that some of the modules (but not all) did previously. This
serialisation should not be needed as the clock is set through the
parameters even when restoring from the checkpoint. In other words,
the state is "stored" in the Python code that creates the modules.
The nextCycle methods are also simplified and the clock phase
parameter of the CPU is removed (this could be part of a clock object
once they are introduced).
This patch classifies all ports in Python as either Master or Slave
and enforces a binding of master to slave. Conceptually, a master (such
as a CPU or DMA port) issues requests, and receives responses, and
conversely, a slave (such as a memory or a PIO device) receives
requests and sends back responses. Currently there is no
differentiation between coherent and non-coherent masters and slaves.
The classification as master/slave also involves splitting the dual
role port of the bus into a master and slave port and updating all the
system assembly scripts to use the appropriate port. Similarly, the
interrupt devices have to have their int_port split into a master and
slave port. The intdev and its children have minimal changes to
facilitate the extra port.
Note that this patch does not enforce any port typing in the C++
world, it merely ensures that the Python objects have a notion of the
port roles and are connected in an appropriate manner. This check is
carried when two ports are connected, e.g. bus.master =
memory.port. The following patches will make use of the
classifications and specialise the C++ ports into masters and slaves.
Make them easier to express by only having the cxx_type parameter which
has the full namespace name, and drop the cxx_namespace thing.
Add support for multiple levels of namespace.
creation and initialization now happens in python. Parameter objects
are generated and initialized by python. The .ini file is now solely for
debugging purposes and is not used in construction of the objects in any
way.
--HG--
extra : convert_revision : 7e722873e417cb3d696f2e34c35ff488b7bff4ed
supposed to and make sure parameters have the right type.
Also make sure that any object that should be an intermediate
type has the right options set.
--HG--
extra : convert_revision : d56910628d9a067699827adbc0a26ab629d11e93