An Open Source CPU!?

[Music] have you ever found yourself relaxing in the tub thinking hmm how could i design my own cpu okay maybe that's not quite as likely but let's say you work for a large company that is legitimately looking to do something like that where do you even start i mean i guess could you license intellectual property from intel or arm i mean maybe but that kind of thing is going to cost you an arm and a leg so then what other options are out there well when we asked just that question to krista asanovich co-creator of risk five he was quick to bring over actually like a team of people and one of these computers based on risk 5's free and open architecture which surprisingly functions like a normal pc and i cannot wait to tell you guys about this thing [Music] so there's a good chance that right now you're thinking okay cool tech demo quake 2. but i'm not going to have one of these open processors in my computer anytime soon so why should i care well you should care because you actually can expect to find risk 5 processors in your gaming rig much sooner than you'd think just for the time being not as your primary central processing unit so nvidia and western digital along with around 100 other companies will soon be shipping products with risc-5 microprocessors on board due to it having better efficiency better security and that sweet sweet royalty-free license to boot in order to appreciate how cool risk 5 actually is though we do need a bit of a history lesson so back in the 1960s ram was made using tiny magnetic cores and these were super duper slow compared to the vacuum tube processors of the time so to make sure that the processor wasn't just wasting cycles while the ram was catching up every instruction from the memory ran a little program hardwired inside the processor called microcode with the 70s came the space race where scientists figured out how to put a lot of transistors on one chip which meant that now fast memory could be put on the same chip as the cpu so then microcode just got thrown in the garbage bin of history right no just kidding a lot of that same microcode from way back then actually still exists in modern computers for software backwards compatibility the legendary intel 8086 cpu pioneered a new computer architecture x86 but you could make the argument that it was just hastily thrown together by intel engineers in just a few weeks and they they had no way of knowing that it was going to become the de facto home computer architecture for decades to come thanks to its use in the original ibm pc but with an average of one instruction being added every couple of weeks since its inception x86 has gone from poorly thought out to today ballooning to over 1500 instructions i mean think of it like the english language how many words do you use on a daily basis versus how many are in the dictionary in a modern world this kind of bloat leads to inefficiency not to mention needless difficulty for anyone that wants to make a processor so why is everyone still on x86 well software support is a big part since porting windows and all of its programs to a new architecture has proven we could use a word like inconvenient i mean look at windows rt on arm total flop on top of that creating a good architecture in the first place is freaking hard to be clear those guys that threw it together were pretty talented they were pretty talented team and it's been a lot easier over the last several decades to just make the transistor smaller and pack in more of them at least it was easier until moore's law kind of petered out and huge leaps forward in cpu speeds basically stopped in the last five or so years so clearly a more usable alternative to x86 or arm was needed one that was created with modern processors in mind and using the power of hindsight that other architectures didn't get to benefit from which is where krista and his team come in creating the reduced instruction set computing five or risk 5. the core of which has less than 50 instructions instead of 1500ish there will probably be more by the time this video is out now those 50 instructions are locked down and won't be changing in the future so ideally a program made 60 years from now using risk five should work just fine on processors being made today i mean slowly though but what if those 50 instructions aren't enough well risk five is customizable meaning that if say nvidia wants to create a processor that is specialized for ai and graphics they could actually add extra instructions for their task allowing for greater hardware specialization and much greater efficiency but of course there have been open source instruction sets before and they have never taken off so back to that question why do we care about this one well the members list for the risk five foundation is kind of a who's who of the biggest tech companies including but not limited to google samsung nvidia tesla ibm and a hundred or so more including a startup founded by the creators of risk five sci five to help kick start risk five adoption and to avoid that chicken and egg problem with hardware and software by creating the world's first commercial risk 5 silicon so this right here is the fu540 which stands for freedom unleashed 540 definitely not what else fu could mean towards lock down standards so so this one thousand dollar processor is well not particularly fast with four cores that on this particular board can clock up to 1.6 gigahertz on a 28 nanometer process node but breaking speed records is not exactly the point when this processor was announced with support for linux back in february you could run pretty much nothing on it but here we are just six months later and 80 of the debian software library has been compiled for risk five meaning that all you need to install almost any app is a quick app get command but of course the point of this board isn't for you to run games on it even if it does run quake 2 thanks to this configuration so we've got the processor here which sits under this tiny little heat sink and fan then we've got the ram so that's eight gigs of ddr4 with ecc we've got gigabit ethernet right here we've got usb and uh let's see yeah we've got a micro sd card reader right here but what makes it unique is this chip connector right here this allows for you to connect the cpu to well anything you'd like so currently on the table in front of me here we've got another unit that's connected to an fpga that handles pci express lanes for what you could kind of consider a a larger scale motherboard here so now we've got a graphics card this is just a regular hd 6450 amd graphics card we've got a samsung m.2 drive on the other side plus we've got a bunch more i o but you know what else you could connect here pretty much anything this allows companies to build whatever custom solution they would like onto the sci-5 processor board so the tldr is that it can interface with whatever fpga or custom silicon is needed while getting the advantages of the risc-5 instruction set linux support and also all of the intellectual property and legal work that sci-fi has already put in to make sure that things like the ram work with the cpu so in the future sci-fi is looking to have sort of a domino's pizza approach to custom chips where a company can come in and add on bits for say image processing or autonomous car ai but now you're probably wondering why have it open source then if sci-5 is sinking all this time into making these custom chips work and into the risk 5 instruction set why not lock it down so they can keep all the money well say that a company has a driver issue normally they would have to go to intel or whoever to get it fixed causing a lot of work on both sides and potentially making the company have to disclose what exactly they're working on whereas when the software and the hardware is open source the company can just fix the bug and then upload a fix for the community afterwards the open source nature is also appealing to companies because if they invest in developing for risk five and sci five goes under then all of those man hours don't get wasted what's going to cause the real stiction of risk five though is in education because it's royalty free the most popular computer architecture textbooks being published right now and courses being taught in undergrad and graduate programs around the world use risk 5 to show students how computer hardware works on a very low level previously some fantasy architecture would have to be used and then when a computer engineer would enter the field they'd finally get to work with a messy proprietary isa so since very few students will switch up what architecture they use once entering the field the idea here is that you can expect a lot more custom hardware being made using risk 5 in the future in your hard drives in your graphics cards in your cars and maybe maybe someday even as the primary architecture of your home computer and you'd be running games more complex than quake 2 by that time so thanks for watching guys if this video sucked um hi amd and intel and arm i guess hi guys uh but if you liked it get subscribed hit the like button or check out the link to where we where to buy the stuff we featured yeah i guess leveling i guess you could buy one if you really want to in the video description also linked in the description is our merch store which has cool shirts like this one and our community forum which you should totally join

Channel: Linus Tech Tips

Views: 2,256,760

Keywords: RISC-V, SiFive, Open Source, ISA, x86, Intel, CPU

Id: L8jqGOgCy5M

Length: 11min 52sec (712 seconds)

Published: Wed Aug 22 2018

Reddit Comments

[u/-McClinticSphere-]

Straight from the man who invented the GNU hardware

[u/go_comatose_for_me]

I look forward to the day that there are reasonably priced RISC-V home computer parts.