Preliminary work on a mechanism for testing a customized architecture

Hardware customization for scientific applications has shown a big potential for reducing power consumption and increasing performance. In particular, the automatic generation of ISA extensions for General-Purpose Processors (GPPs) to accelerate domain-specific applications is an active field of research. Those domain-specific customized processors are mostly evaluated in simulation environments due to technical and programmability issues while using real hardware. There is no automatic mechanism to test ISA extensions in a real hardware environment. In this paper we present a toolchain that can automatically identify candidate parts of the code suitable for acceleration to test them in a reconfigurable hardware. We validate our toolchain using a bioinformatic application, ClustalW, obtaining an overall speed-up over 2x.Postprint (published version

Automatic generation and testing of application specific hardware accelerators on a new reconfigurable OpenSPARC platform

Specific hardware customization for scientific applications has shown a big potential to address the current holy grail in computer architecture: reducing power consumption while increasing performance. In particular, the automatic generation of domain-specific accelerators for General- Purpose Processors (GPPs) is an active field of research to the point that different leading hardware design companies (e.g. Intel, ARM) are announcing commercial platforms that integrate GPPs and FPGAs. In this paper we present a new framework with a holistic approach that addresses the challenge of design exploration of specific application accelerators. Our work focuses on a target platform consisting of a GPP with a reconfigurable functional unit. The framework includes a reconfigurable 1-core 1-thread OpenSPARC with a new programmable specific purpose unit (SPU) inside the OpenSPARC core. In order to program the SPU we have developed an automatic toolchain that profiles an application and discovers its main computing bottlenecks. With that information our toolchain is able to both design hardware specific accelerators that can be automatically mapped in the aforementioned SPU, and generate the binary code necessary to run the application using those accelerators. The OpenSPARC with the new specific application accelerators, defined in a Hardware Description Language, can then be executed and measured. Still awaiting further development, nowadays our framework is a proof-of-concept that shows that this kind of systems can be developed and programmed as easily as a GPP. In a near future it would be the source of very interesting information about the capabilities and drawbacks of those mixed GPP-FPGA systems.Postprint (published version

A high level test processor and test program generator

Embedded test within integrated systems allows to overcome some of the difficulties found when testing using only an external tester. The reutilization of a reconfigurable FPGA-like block that may exist in certain SoC systems, enables the implementation of on-chip test processors highly optimized to meet the specific requirements of the test procedure for each block. The fast reconfiguration of SRAM-based FPGA blocks allows sharing the same physical area among the set of different circuits that may be necessary to implement the on-chip test suite of the whole system. This paper addresses the high level generation of specific programmable processors for testing different blocks within integrated systems, taking advantage of such existing programmable resources. The work presented herein proposes a methodology and a set of automation tools to enable the automatic generation of dedicated custom processor architectures for specific test operations, as well as the corresponding test programs. This facility can be seen as disposing of a highly flexible and optimised embedded tester, supplied as an intellectual property (IP) module and its software. The approach being proposed is based in the implementation of a test processor as an Application Specific Instruction-Set Processor (ASIP), whose set of conventional and dedicated instructions are automatically derived from a software specification of the test operation to be implemented. The actual configuration of the test processor is determined by the type of instructions the test designer uses in the test program. The processors instruction set is configured automatically from the source code of the program to be run, in order to include only the exact instructions required for that task. The generation of a test processor starts with a software specification of the test operation to be performed. Presently, this specification is done using a program written in an assembly level language whose instruction set comprises all the general purpose instructions supported by the processor core, plus an extra set of complex instructions that are responsible for the operation of the peripheral specific blocks. From this specification, a custom programmable processor is generated as a set of synthesisable HDL modules, including the identification of peripheral blocks associated to specific instructions, and the set of constrains and assignments required to instantiate and map these modules onto the FPGA. These descriptions are then forwarded to the specific FPGA technology mapping and implementation tools, to create an application-specific processor that includes only the instructions referred in the source code