Changes between Initial Version and Version 1 of DsxDodumentation

Timestamp:

Jan 27, 2008, 5:43:49 PM (16 years ago)

Author:

alain

Comment:

--

DsxDodumentation

@@ +1 @@
+[[PageOutline]]
+
+= A) Goals =
+
+DSX stands for ''Design Space eXplorer''. It helps the system designer to map a multi-threaded software application
+on a multi-processor hardware architecture (MP-SoC) modeled with the SoCLib components.
+
+It supports the hardware software codesign approach, and allows the designer to define successively :
+ * the hardware architecture : number of processors, number of memory banks, peripherals, etc.
+ * the software application structure : Task & Communication Graph
+ * the mapping of the software objects on the hardware components
+
+The software application must be statically defined as  a '''Task & Communications Graph'''.
+The number of tasks (defining the coarse grain parallelism), and the communication channels between
+tasks should not change during execution. The two targeted application domains are the telecommunication
+applications (where the tasks are handling packets or packet descriptors), and multi-media applications
+(where the tasks are handling audio or video streams).
+
+A specific goal of DSX is to allow the system designer to control not only the the placement of the 
+tasks on the processors, but also to control precisely the placement of the software objects (execution stacks,
+communication buffers, synchronization locks, etc.) on the memory banks. In shared memory multi-processors
+architectures with several physically distributed memory banks, such control is mandatory to optimize
+both the performances and the power consumption. 
+
+= B) General Principles =
+
+The general principles are the following:
+ * The coarse grain parallelism is 
+ * The software tasks are supposed to be written in C or C++.
+ * 
+ * [https://www-asim.lip6.fr/trac/mutekh Mutek] : OS kernel for embedded MPSoCs
+
+== B1)  API SRL (System Ressources Layer) ==
+
+We want to map the multi-threaded software application on several hardware platforms,
+without any modification of the task code. One important platform is a POSIX compliant
+workstation, as we want to validate the multi-threaded application by running it on a 
+the workstation before starting the mapping on the MPSoC architecture.
+
+DSX defines a '''system Ressource Layer''' API (SRL), that is an abstraction of the synchronization
+and communication services provided by the various target platforms. The SRL API helps
+the programmer to distinguish the embedded application code from the system code used for
+inter-tasks communications and synchronizations.
+
+Three  platforms are supported :
+ * Any Linux (or Unix)  workstation  supporting the POSIX threads,
+ * MP-SoC architecture using the MUTEK/D operation system,
+ * MP-SoC architecture using the MUTEK/S operating system,
+
+MUTEK/D is an embedded, POSIX compliant, distributed,  operating system for MP-SoCs, 
+while MUTEK/S is an optimized version: the performances are improved, and the memory
+footprint is reduced, at the cost of loosing the POSIX compatibility. 
+
+== B2)  DSX/L language ==
+
+DSX/L is a language based on PYTHON, that allows the system designer to describe :
+ * the Task & Communication Graph (TCG)
+ * the MP-SoC hardware architecture (using the hardware components available in SoCLib).
+ * the mapping of the TCG on the MP-Soc architecture. 
+
+The DSX/L script execution generates the binary code executable on the workstation, the 
+SystemC model of the ''top cell'' correspondint to the MP-SoC architecture, and the binary
+code that will be uploaded in the MP-Soc embedded memory. 
+