Open Source Vs. Commercial RISC-V Licensing Models


Everybody is familiar with commercial licensing from traditional processor IP vendors such as Arm, Cadence, and Synopsys. But in discussing the RISC-V Open Instruction Set Architecture (ISA), there is widespread confusion of terminology with RISC-V often being described as “open source.” Some have even accused vendors of commercial RISC-V IP such as Codasip or Andes as not being in the spir... » read more

Impact Of Instruction Memory On Processor PPA


The area of any part of a design contributes both to the silicon cost and to the power consumption. A simplistic following of the “A” in a processor IP vendor’s PPA numbers can be misleading. A processor is never in isolation but is part of a subsystem additionally including instruction memory, data memory, and peripherals. In most cases, instruction memory will be dominant and the proc... » read more

Embedded Processor Requirements And OS Choice


For each embedded product, software developers need to consider whether they need an operating system; and if so, what type of an OS. Operating systems vary considerably, from real-time operating systems with a very small memory footprint to general-purpose OSes such as Linux with a rich set of features. Choosing a proper type of operating system for your product – and consequently w... » read more

Defining Processor Core Complexity


The more complex a processor core, the larger the area and power consumption. But increasing complexity is not a single dimension, as processors can be more complex in different ways. In selecting a processor IP core, it is important to choose the right sort of complexity for your project. Some ways of thinking about complexity include: Word length Execution units Privilege/prot... » read more

Understanding The Performance Of Processor IP Cores


Looking at any processor IP, you will find that their vendors emphasize PPA (performance, power & area) numbers. In theory, they should provide a level playing field for comparing different processor IP cores, but in reality, the situation is more complex. Let us consider performance. The first thing to think about is what aspect of performance you care about. Do you care more about the ... » read more

About The SweRV Core EH2


In mid-May, CHIPS Alliance announced the open sourcing of the SweRV Core EH2 and SweRV Core EL2 designed by Western Digital. These cores, as well as the earlier EH1, are now supported by Codasip’s SweRV Core Support Package which provides all of the components necessary to design, implement, test, and write software for a SweRV Core-based system-on-chip. But what is SweRV Core EH2? ... » read more

Domain-Specific Processors Enable More Than Moore


Last month was the 55th anniversary of Gordon Moore’s famous paper Cramming more components onto integrated circuits. He took a long-term view of the trends in integrated circuits being implemented using successively smaller feature sizes in silicon. Since that paper, integrated circuit developers have been relying on three of his predictions: The number of transistors per chip increas... » read more

The Hidden Costs of Open Source


It is often implied that if you use an open source processor core there are no costs associated with using it. Of course, the RTL may be free of a license fee and royalties and it might be possible to access a free of charge toolchain for RISC-V, but there are plenty of hidden costs associated with using the core in a real integrated circuit design. If you are using the core in a product... » read more