“Think Differently”
We’ve all heard this saying go around everywhere. It’s there in your local Apple store, it’s quoted in your favourite motivational videos on YouTube, it’s mentioned on social media influencers posts on Instagram, heck, you’d even find it spray-painted across an empty wall as graffiti art in cities all over the world. Some might say, this perfectly encapsulates the mission and vision of the multinational technology giant that is, Apple. From two friends making it official on the 1st of April, 1976 to becoming valued at 1.58 trillion USD as of June 2020, Apple has come far and a long way in bringing about the best user experience for their users through their multiple innovations in hardware and software, as stated by their mission statement for the year 2020.
In 2005, Apple’s then CEO, the late Steve Jobs announced that Apple would transition their personal computer Mac to use PC-standard Intel x86 processors. Come the year 2020 and they look interested to make another CPU shift that could prove to be far more significant to the future of technology.
The decision to shift to the x86 processor made sense then, owing to the fact that Apple neither had an in house chip design team nor did they have the capital required to pursue their interests in this field. However, kicking off investments from their profits from the iPhone 4 into custom ARM application processors that they implemented in their IPad 2, released in 2010, using its own A4 chip, they slowly began to enter the ball game themselves.
On the other hand, over time Intel’s hold in the 5G race has significantly reduced with Apple and other companies shifting to Qualcomm modems for their mobile devices as opposed to the formerly famous Intel Modems. As it became clearer that Intel couldn’t keep up with the needs of the 5G industry, Apple shifted its focus to Qualcomm modems and subsequently their own.
Now coming to RISC-V. It is an open standard instruction set architecture based on the already established Reduced Instruction Set Computer (R-I-S-C) principles. The RISC-V foundation works towards maintaining and publishing intellectual property related to RISC-V’s definition.
To put things into perspective, what Linux is to OS, RISC is to computer architectures – Open Source. That is to say, if Apple wasn’t even a member of this foundation before, it could still use RISC-V to develop its main processor and all other modules, owing to the fact that ARM architecture is found in most modules, bluetooth, wlan, etc.
The open source-ness of RISC allows Apple to use it without a license, thus avoiding all legal battles it got into with Intel and Qualcomm for the same purpose. Apple’s innovative vision means that it would prefer for most of its designs to cater to the wants and needs that the company deems fit. This would mean getting control of all the modules necessary to do so, something which wasn’t an option previously when they had partnered with Intel and Qualcomm. These are only a small portion of the reasons Apple has to adapt a RISC-V architecture over the ARM architecture in the long run.
Switching architectures will not be a walk in the park, even for a company valued in the trillions. The advantage that the RISC architecture provides over the CISC architecture, present in Intel x86 processors, is the ability to gain more control over all the modules which would call for more optimisation and creativity in the designs, something Apple has stood for since its inception back in 1976. RISC uses simple instructions that can be executed in one clock cycle as opposed to the CISC way of implementing complex instructions over multiple clock cycles. Thus the RISC architecture would require more RAM but executes one instruction per clock cycle for predictable processing which has really come a long way in pipelining. RISC emphasizes larger program code sizes, due to a fairly smaller instruction set, so in its essence, multiple steps done in succession may equate to one step in CISC. The RISC architecture emphasizes software over hardware. The RISC instruction set requires one to write more efficient software (e.g., compilers or code) with fewer instructions. CISC ISAs use more transistors in the hardware to implement more instructions and more complex instructions as well.
One of the major roadblocks RISC faced in the past was the inefficient compiling machines but over time even they’ve come to suit the needs of the RISC architecture. That along with Intel’s drag in the 5G race, is slowly making RISC the next big thing.
To conclude, I’ll quote Nike’s animated football movie, The Last Game – “You need to risk (risc) everything to win”.
– Article by Ayush Saran, 3rd year Department of Electrical and Electronics Engineering