Starting in the summer of 2010, the Berkeley research team spent approximately four years designing and developing a complete new instruction set. This new instruction set is called RISC-V. The instruction set has been questioned by many parties since its official release in 2014. By 2017, the Indian government stated that it would vigorously fund RISC-V-based processor projects, making RISC-V a popular choice in India. De facto national directive set. This year, domestic support for RISC-V was provided from the national policy level, and Shanghai became the first city in China to include RISC-V as a target of government support. RISC- V camp.
After just a few years, RISC-V not only has policy support, but also corporate and academic circles are paying increasing attention to this open source instruction set, and even Arm is feeling the pressure. Since RISC-V was born at Berkeley University in 2010, one of the most common voices in the industry is that RISC-V may change the existing competitive landscape of processor architectures dominated by Arm and Intel , IOT and other embedded markets have had an impact.
The difference between ARM and RISC-V
Both the ARM architecture and the RISC-V architecture originated from the reduced instruction computer RISC in the 1980s. The biggest difference between the two lies in their advocating simple technical style and completely open model. ARM is a closed instruction set architecture. Many manufacturers that only use the ARM architecture can only adjust product frequency and power consumption according to their own needs, and are not allowed to change the original design. After decades of development and evolution, the CPU architecture has become extremely Complex and lengthy, ARM architecture documents are thousands of pages long, with a complex number of instructions and numerous versions. They are neither compatible with each other nor support modularity, and there are expensive patent and architecture licensing issues. On the other hand, RISC-V was positioned as a completely open source architecture from the beginning of its design, avoiding the detours of decades of development of computer systems. The architecture document only has more than 200 pages, and the number of basic instructions is only more than 40. At the same time, The instruction set supports all architectures, and the modularity allows users to freely customize and configure different instruction subsets according to needs.
Where will the competition between ARM and RISC-V go in the future?
At present, ARM occupies the vast majority of the market for processor IP represented by mobile devices, while RISC-V is a rising star. So, where does the future go from here?
The competition between ARM and RISC-V is a bit like the battle between Windows and Linux at the end of the last century. The future competition pattern between ARM and RISC-V may also be similar. First of all, it is almost certain that RISC-V has basically no chance in ARM’s traditional advantage area, that is, the mobile phone field, because mobile phones are unlikely to completely change the processor core after ten years of iteration. This is also different from the current Windows after twenty years of iteration. After years of hard work, it is still the leader in operating systems in the PC market. However, in emerging fields, RISC-V and ARM are both on the same starting line, and RISC-V is likely to beat ARM, or at least occupy a considerable market share, with its open source instruction set and other features. At present, such emerging markets are mainly the Internet of Things market. The IoT market has long-tail characteristics, with many market segments and high requirements for power consumption. Therefore, RISC-V, which can flexibly modify the instruction set and chip architecture design for different applications, has advantages. Compared with When using ARM, you can often only make a standardized design, and it is difficult to achieve differentiation. In addition, the IoT market is more cost-sensitive, and the free licensing feature of RISC-V is also important to chip manufacturers. In the list of the RISC-V Foundation, we can see companies such as Qualcomm and MediaTek that focus on the Internet of Things. In the currently popular AI chip market, there is no clear advantage or disadvantage between ARM and RISC-V.
This is because high-performance AI chips, whether using ARM or RISC-V cores, are mainly used as controllers. The most important and core computing unit is often designed by circuit designers without using IP; On the other hand, AI chips tend to have larger profit margins, so the free nature of RISC-V does not bring particularly big advantages.