7 ms·
SiFive Introduces 7 Series RISC-V Cores with E7, S7 and the U7 Series
- jbeard4 8y agoI am pretty excited about RISC-V. Hoping to see a v8 JavaScript and Node.js port in the future.
- thethirdone 8y agoThat shouldn't be super hard. I don't think there is much assembly in either. And C can be compiled to RISC-V already. My only experience porting node was to a specialized ARM system a while ago, so ARM support may have been already built in or things may have changed. edit: as people have commented, there indeed is a fair amount of arch specific stuff for reference the mips directory https://github.com/v8/v8/tree/master/src/mips64 https://github.com/v8/v8/tree/master/src/mips64
- comex 8y agoV8 has a JIT, which is always going to require work to port to a new architecture. But the new-ish TurboFan backend is supposed to have the architecture-dependent parts relatively well factored out[1], so it's not as hard as it might be. https://docs.google.com/presentation/d/1_eLlVzcj94_G4r9j9d_Lj5HRKFnq6jgpuPJtnmIBs88 https://docs.google.com/presentation/d/1_eLlVzcj94_G4r9j9d_L...
- Matthias247 8y agov8 is a JIT compiler. It emits instructions for specific architectures. So even if it's not written in assembly, it has some very architecture specific parts in it.
- Iwan-Zotow 8y ago> I don't think there is much assembly in either. it has nothing to do with assembly, or ability to compile C it is basically typical compiler with front-end and back-end. While front-end is platform independent and could be ported easily, back-end usually takes quite some time to retarget for a different architecture
- nicenewsbc 8y agowhen?
- gnulinux 8y agoWhen can I buy an affordable, complete RISC-V computer? I've been long planning to cook my own with FPGA but it seems like soon we'll start getting affordable RISC-V CPUs with other utility support?
- deleted 8y ago[deleted]
- antome 8y agoAffordable RISC-V systems will only happen if they reach a comparable level of mass production as proprietary systems. What you will more likely see for now is a gradual increase in the number of components on GPUs, HDDs etc which use RISC-V instead of ARM or something else. The ISA is only a part of the cost equation.
- zik 8y agoThere are none yet. RISC-V is likely to appear in embedded and mobile devices before a full desktop machine is competitive with Intel processors.
- mkl 8y agoWhy not embedded? It seems like that would happen well before full desktop machines and competitive speeds.
- mrweasel 8y agoIt's most likely going to be like with ARM and be embedded only, sadly. There's a large number of us, not large enough though, that want a standard ATX motherboard, with PCI-Express and an ARM, RISC-V or PowerPC processor (well an affordable PowerPC).
- PinkMilkshake 8y agoI've only had a passing interest in learning assembly. It's always been in the "maybe one day" category. But after learning about how small the RISC-V instruction set is (less than 50 apparently, but I can't find a citation for that anywhere), I'm far more motivated to get into it.
- krackers 8y agoThe base instruction set is small enough to fit on a card. Of course adding the floating point, vector extensions, etc. would make it a bit harder to squeeze into a single page, but I think it would still end up smaller than the x64 spec. https://www.cl.cam.ac.uk/teaching/1617/ECAD+Arch/files/docs/RISCVGreenCardv8-20151013.pdf https://www.cl.cam.ac.uk/teaching/1617/ECAD+Arch/files/docs/...
- trhway 8y ago>But after learning about how small the RISC-V instruction set is (less than 50 apparently, but I can't find a citation for that anywhere), I'm far more motivated to get into it. from the times when x86 wasn't that big: http://pastraiser.com/cpu/i8080/i8080_opcodes.html http://pastraiser.com/cpu/i8080/i8080_opcodes.html 30 years ago we were typing the hex codes of those commands straight into the Forth words bodies using the mental copy of that table (as you see it has very logical easy to remember organization)
- snvzz 8y agoOr the beautiful 68000. http://goldencrystal.free.fr/M68kOpcodes-v2.3.pdf http://goldencrystal.free.fr/M68kOpcodes-v2.3.pdf
- IcePic 8y agoCheck out MSP430 is you want small instruction sets, also fits on one page if needed.
- Posibyte 8y agoI recommend the 6502[1] if you're just starting. What you learn applies almost everywhere, and it's very much a what-you-write-is-what-happens sort of processor. No branch prediction, no caches, no fancy features. Its op-set is very small and highly expressive. They still make them, in fact. That said, whether you choose to start with it or RISC-V, from personal experience SiFive's implementations are phenomenal. I used one of their free-implementations, and I was blown away by how easy it was to use their automated tools to build a core exactly the way I wanted. Not as easy as generating a NIOS core, but much more capable. With an Artix-7, I had a very capable low-range processor in about an hour. [1]: https://skilldrick.github.io/easy6502/ https://skilldrick.github.io/easy6502/
- mhb 8y agoHiFive1 - Arduino RISC-V Dev Board The HiFive1 is a low-cost, Arduino-compatible development board featuring the Freedom E310 making it the best way to start prototyping and developing your RISC‑V applications. Not only can the HiFive1 help build RISC-V platforms, but it is also the first commercially available option to do so! The HiFive1 can simply be plugged into your computer via the micro USB port located to the front of the board. Additionally, the HiFive1 comes programmed with a simple bootloader and a demo software, that way you aren’t restricted to the Arduino IDE if you don’t choose to do so. https://www.sparkfun.com/products/15026 https://www.sparkfun.com/products/15026
- ivoras 8y agoHmm, does it really have only 16 KiB of RAM or am I misinterpreting the spec? What would be the use case for a 320 MHz processor with 16 KiB RAM? Even ESP8266 has 80 KiB and runs at 80 MHz.
- SloopJon 8y agoThe only place I see that mentions 16 KB is the instruction cache on the S7 monitor core. Apart from cache, it doesn't look like any of these include RAM.
- crankylinuxuser 8y agoThat's fairly standard. The problem there is going to be attaching ddr3 modules to a board. BGA is a pain in the ass for anything past 10x10 using a toaster oven. And for doing it "right" you really need xray QA.
- brianolson 8y agoSiFive press release here: https://www.sifive.com/press/sifive-core-ip-7-series-creates-new-class-of-embedded https://www.sifive.com/press/sifive-core-ip-7-series-creates...
- aidenn0 8y agoThe M7 is an out-of-order processor, these all look to be in-order. Many artificial benchmarks (including Dhrystone) are very forgiving of in-order stages, so I would expect this to underperform relatively to a similarly benchmarked M7.
- Zeetah 8y agoM7 is actually an in-order processor. It does have six-stage dual-issue pipeline.
- aidenn0 8y agoOh you're right. It has speculative execution, but is otherwise strictly in-order, my mistake.
- microcolonel 8y agoApparently good Cortex-M7s get around 5 CoreMark/MHz (NXP crossover, STM32H7), so it's almost identical per MHz, and I'm willing to bet that they can get higher frequencies with less effort (if you look at the SiFive MCUs, they run at stupid frequencies compared to similar competing cores, and were generally available almost two years ago now). For further comparison, the Broadwell Xeon I'm typing this on gets about 7.2 CoreMark/MHz (running at full turbo, 4GHz, on one core).
- jabl 8y agoIs this based on the open source rocket chip, or is it a proprietary design?