M3-SCoPE: Performance Modeling of Multi-Processor Embedded Systems for Fast Design Space Exploration - Multi-objective Design Space Exploration of Multiprocessor SoC Architectures - page 26

Fig. 2.3 Simple XML system
description containing
information about the HW
components, its instances, the
operating system, the SW
applications and the task
allocation. The description
represents a simple system
containing a processor, bus
and memory, running a
typical "Hello world"
application

2.2.1.1 Configuration of the System Components

The first configuration option is used to tune the characteristics of the system com-
ponents. The values of all parameters in the XML file can be replaced by identifiers
when the parameter is a configurable one. For example, the bus frequency that was
indicated in Fig. 2.3 ( 200 MHz) can be been replaced by the identifier "FREQ" .
To select a configuration, the values of all identifiers must be assigned in the Sys-
tem Configuration File. Thus, to perform different simulations it is only required to
modify the value-identifier pairs in the System Configuration file (Fig. 2.2 ). Applying
this solution, the simulation of each experiment required by the DoE is performed
by substituting the identifiers of the configurable parameters by the selected values
and creating the corresponding system model.

2.2.1.2 Replication of System Components

The second configuration option is to indicate the number of times a system compo-
nent is replicated. To do so, a new XML "repeat" clause is provided. This clause
defines the number of times the element is repeated, an index identifier and the initial
index value. Figure 2.4 corresponds to an extension of the system description in Fig.
2.3 considering that the number of CPUs in the system can be set by the "CPUS"
parameter. This parameter must be assigned in the System Configuration file.
The "repeat" clause can be used to replicate both single components and groups
of components, copying complete parts of the system architecture. If the value is set
to '0', the element is not placed in the system. This option is used to add or delete
different components within the system, including modifying SW components, HW
components and the communication infrastructures. As a consequence, different
platform architectures can be described.