These are the kind of chips that India always wanted, but could not make. Now, computer scientists and a student team from the IIT- Madras have developed the first of a family of six industry-standard microprocessors.
The initial batch of 300 chips, named RISECREEK and produced under Project Shakti, have been fabricated free at Intel’s facility at Oregon, U.S., to run the Linux operating system.
The IIT team says its microprocessors can be adapted by others, as the design is open source. They optimise power use and compete with international units such as the Cortex A5 from Advanced RISC Machines (ARM).
On the test bench, the IIT design fared better than the A5, measured in terms of the DMIPS per megahertz rating, scoring 1.68 against the competition’s 1.57. At a frequency of 350 MHz, RISECREEK can meet the demands of defence and strategic equipment such as NAVIC (Indian Regional Navigation Satellite) and Internet of Things (IoT) electronics, its developers say. “Our process helps us develop the processor three times sooner than industry standards,” says Kamakoti Veezhinathan, Professor of Computer Science at the IIT- Madras, who led the project.
What makes RISECREEK different is the open source nature of the designs. “This is made in India, but even if it were made in the U.S., it would be contemporary,” says G.S. Madhusudan, project adviser from the IIT- Madras.
The team, led by Dr. Neel Gala, an alumnus of the IIT- Madras, is thrilled, not just because it developed a viable industry grade chip, but also because the process can be tapped for future efforts in semiconductors. “The Shakti plan started in 2014 as an IIT-M initiative. Last year, the Union Ministry of Electronics and Information Technology funded a part of the project,” says Dr. Kamakoti.
Family of six
The plan includes a family of six types of microprocessors. The first to be ready is the C class, RISECREEK. The E class of microprocessors that can be used in smart cards, IoT devices, fan/motor controls, etc, is almost ready and the I class, which can be used for mobile phones, desktops and mobile phones is soon to follow. The design for the S class which can be used for enterprise class servers is underway, and the H class, which will be used for building High Performance computers with a massive parallel processing capacity.
The H Class is part of the next phase of development, which the team calls the Para-SHAKTI (parallel SHAKTI) project. Para-SHAKTI will make microprocessors for indigenous high-performance computers with over 32 SHAKTI cores.
“The Shakti project is not aimed at only building processors. It also aims to build high speed interconnects for servers and supercomputers based on variants of the RapidiIO and GenZ standards. These are key to build large clusters of processors to get Petaflop and Exaflop level supercomputers,” says Mr. Madhusudan.
With a team of about eight students and three computer scientists, the team used BlueSpec System Verilog language to capture the processor functionality. Everything from that to making the final chip layout was done within the campus. The chip layout was sent to Oregon, to be fabricated by Intel. Once that was done, mounting the chip on a 10-layer verification board and bringing up the chip was done again at IIT Madras. The board bring- up and booting Linux was done in four days. “There are 70 million instructions from the point we switch on the system till the prompt comes. The chip executed these instructions without any bug at the first shot. This gives a lot of confidence to move ahead,” says Dr. Kamakoti.
Intel has fabricated the chip free of cost, and the team incurred a development cost of about ₹1.2 Crore. Regarding vulnerabilities due to outsourcing the fabrication of the chip, he says, “Since the entire design has been developed in-house, it is extremely difficult for a foundry to add backdoors or security vulnerabilities. But yes, an external fab can always induce vulnerabilities. A probable solution for this is to move towards a controlled fab.”