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Re:Arm kills off its anti-RISC-V site after own staff revolt by Nokinside on Wednesday July 11, 2018 @04:50AM (#17505425)
RISC-V is open instruction set, not open microarchitecture.

You won't see high performance open source micrarchitectures that implements RISC-V core.

Nobody is going to invest $300-$500M to develop new competitive open source microarchitecture (patent free?) every 5-10 years for RISC-V that can compete with Intel, AMD and others.

Re:Arm kills off its anti-RISC-V site after own staff revolt by mtgx on Wednesday July 11, 2018 @07:28AM (#17506072)
The EU has already chosen RISC-V as one of the two options for developing chips for its supercomputers:

https://www.slideshare.net/insideHPC/european-processor-init...

I imagine China and India will eventually go with RISC-V, too. Maybe Nvidia will have "another go" at designing its own CPU microarchitecture, too, if they get tired of Arm's shenanigans. Nvidia has already chosen RISC-V for its GPU microcontroller.

Re:Arm kills off its anti-RISC-V site after own staff revolt by Nokinside on Wednesday July 11, 2018 @10:06AM (#17506974)
R&D from EU, China, Japan and India are not going to result open source microarchitectures. Government supports basic R&D but the end product will be commercial closed source IP and patented.
Re:Arm kills off its anti-RISC-V site after own staff revolt by mlyle on Thursday July 12, 2018 @12:21AM (#17512167)
Re:Arm kills off its anti-RISC-V site after own staff revolt by Nokinside on Saturday July 14, 2018 @12:22PM (#17530926)
>While we do plan to tape out a few variants, given the foundry NDA requirements, we will not be able to publish any layout/backend data. But the ASIC syntesis and P&R data to teh extent possible will be published to allow others to replicate our ASIC flow.
Re:Arm kills off its anti-RISC-V site after own staff revolt by ant6n on Wednesday July 11, 2018 @06:35AM (#17505824)
That's like saying u won't see a general purpose, high performance, highly reliable open source operating system for servers and consumers, with a total development cost of more than a billion in terms of total person hours.

Yet here we are.

Re:Arm kills off its anti-RISC-V site after own staff revolt by phkahler on Wednesday July 11, 2018 @07:30AM (#17506078)
And who would make a free Office suite? Or an open source tool chain (we have two now!), or EDA tools, web browser, audio/vide codecs, or....

Once you have a decent base and sufficient interest, peoples incremental changes will get there eventually.

Re:Arm kills off its anti-RISC-V site after own staff revolt by vonmoltke on Wednesday July 11, 2018 @07:58AM (#17506188)
> Once you have a decent base and sufficient interest, peoples incremental changes will get there eventually.

The size of a viable increment in a software project is much smaller than it is in a hardware project. Developing a functional, non-trivial microarchitecture requires significant capital expenditure and coordination of efforts. This requires at least a patron of some sorts to manage the process, where the requirements for that patron are much more significant than "somebody with a listserv".

Re:Arm kills off its anti-RISC-V site after own staff revolt by debatem1 on Wednesday July 11, 2018 @11:34AM (#17507714)
Nvidia is not ignorant of the realities of hardware design. Google spends capital to get what it wants. Western Digital is not just "somebody with a listserv".

Once those players front the money for the ecosystem the incentive to coordinate is there on the fab side. With that in place and good simulation possible, the size of an incremental change is an exercise in release management.

Re:Arm kills off its anti-RISC-V site after own staff revolt by Nokinside on Wednesday July 11, 2018 @10:48AM (#17507360)
You repeat very common misconception and false analogy.

You don't get high volume processor core into silicon by just hacking Verilog/VHDL in your computer and then send it to the foundry for tape-out and manufacturing like you do with some custom ASIC chip.

Intel and AMD start new microarchitecture design work every 2-3 years. The work must progress in tight time schedule or it becomes outdated. It's highly coordinated effort that requires significant capital investment.

You have to lock in goals, select implementation technology, methodology, have expensive tools etc. Behavioral design, physical design and silicon ramp interact constantly. Problems are solved and there are many optimization and validation phases. You need expensive hardware and access to engineers in the foundry and process you are targeting.

I'm sure there will be many completely open RISC-V cores, but not for the high volume uses or latest processes.

Re:Arm kills off its anti-RISC-V site after own staff revolt by tonysdg on Wednesday July 11, 2018 @11:41AM (#17507770)
You yourself repeat a very common misconception and false analogy.

Intel and AMD start new microarchitecture design work every 2-3 years because (Intel, at least) base their sales on offering the latest and greatest. They seek peak performance, which is exactly what gamers/scientists/prosumers want.

But for large swaths of the market, you don't need that. Think of your average consumer/small business owner. By and large, most of them are using 3-5 year old PCs, and even then the processors within those 3-5 year old PCs were probably last-gen when they were purchased.

Or think military -- the ability to have a home-grown, openly-vetted processor that you can tape out with a trusted domestic supplier would eliminate a number of security concerns.

Don't let great be the enemy of good here. If you can build a decent RISC-V core that can compete with an Intel Core 2 Duo, you've got all the horsepower you need for the average consumer.

Re:Arm kills off its anti-RISC-V site after own staff revolt by Nokinside on Wednesday July 11, 2018 @01:54PM (#17508872)
I did not deny that there will be completely free designs for small volume applications and specific niches. They will be very low performance and not going to be competitive in mass markets in low price or high price.

> Think of your average consumer/small business owner.

Optimizing processor for low-cost price is also very demanding.

Re:Arm kills off its anti-RISC-V site after own staff revolt by freeone3000 on Wednesday July 11, 2018 @11:54AM (#17507873)
Core 2 Duo? You're aiming way too high here. A RISC-V core that can compete with a Cortex A9 or a Snapdragon 820 would be exceptional.
Re:Arm kills off its anti-RISC-V site after own staff revolt by lkcl on Wednesday July 11, 2018 @08:36PM (#17511356)
nonsense. rocket-chip has been taped out at 45nm and achieved 1.5ghz, years ago. india's shakti core is going into 20nm and as a 6-stage pipeline will run at 2.5ghz. as that one uses only 120mW, even 16 2.5ghz cores would only consume around 3 watts (!!!).

caveat of course: the L1/L2 cache power consumption isn't included in that figure, but, crucially, with the Compressed Instructions reducing cache misses by 20-25% that's equivalent to having approximately double the I-cache size.

basically by a fresh start they're on to a winner.

Re:Arm kills off its anti-RISC-V site after own staff revolt by tonysdg on Wednesday July 11, 2018 @01:16PM (#17508556)
Maybe a Pentium IV then? I don't think RISC-V -- or any processor really -- gets taken seriously in the desktop/laptop space unless it can compete with one of Intel's earlier chips.
Re:Arm kills off its anti-RISC-V site after own staff revolt by jononor on Wednesday July 11, 2018 @04:35PM (#17510082)
Unlikely that anyone will even try to target desktop/laptop market with a RISC-V CPU, it is a very established market without much future growth. The plays will be in embedded devices, especially areas which requires pheripherals with tight integration with the CPU, this is where an open and extensible ISA can be a significant benefit. Examples today are controllers inside SSDs/SDcards. In future maybe also microcontrollers with integrated machine/deep learning co-processors.
Re:Arm kills off its anti-RISC-V site after own staff revolt by tambourine_man on Wednesday July 11, 2018 @09:21AM (#17506609)
With software, you donate your time and you get the final product.

With hardware, someone, at some point, is going to have to pay to press those chips into real silicon.

Re:Arm kills off its anti-RISC-V site after own staff revolt by valuearb on Thursday July 12, 2018 @01:25AM (#17512360)
Writing software doesn’t require massive investments of capital like making chips does.

And if open source processors feature the same attention to detail and high engineering standards that most open source software projects evidence, they’ll frequently catch on fire or stop working without multiple bug fix patches.

Re:Arm kills off its anti-RISC-V site after own staff revolt by jasonkostempski on Wednesday July 11, 2018 @07:36AM (#17506104)
But software has basically no overhead to produce, improve, fix or deploy.
Re:Arm kills off its anti-RISC-V site after own staff revolt by ant6n on Thursday July 12, 2018 @05:58AM (#17513277)
Low level changes in the kernel will probably take a long time and effort before they are deployed. Many kernel devs probably don't do their work because they need some particular fix for themselves, but rather to advance the overall product.
Re:Arm kills off its anti-RISC-V site after own staff revolt by jasonkostempski on Thursday July 12, 2018 @07:00AM (#17513456)
I'm not trying downplay the most amazing community effort humanity has ever seen. I'm just saying, if you want even a basic CPU, it will take far more generosity than that of a few humans to get it off the ground. Insanely more to fix one, if it's even possible, let alone practical.
Re:Arm kills off its anti-RISC-V site after own staff revolt by ant6n on Friday July 13, 2018 @03:38AM (#17521149)
The initial versions of Linux weren't useful except for people playing around with it -- kind of like RISC-V cpus aren't useful today, except people playing around with fpgas. But it does allow you to relatively easily deploy your CPU using this route.

I'm saying that much linux development nowadays is done far away from actual deployment, just like open source cpu design would be.

Also, it's often paid and driven by companies who have an interest in the existence in these open platforms, so it's not all just based on generosity (and we do see companies are interested in RISC-V cpus).

Re:Arm kills off its anti-RISC-V site after own staff revolt by nickik on Wednesday July 11, 2018 @06:29AM (#17505794)
> You won't see high performance open source micrarchitectures that implements RISC-V core.

You don't have to spend $300-$500 to get to a reasonable performance. There are multiple people who are interested in this.

The EU and India have processor initiatives (including high perf) that will use RISC-V. Many universities, non-profits, companies will continue to work on the current open-source chips and combined with open source.

Of course it will take time but blanked 'You won't see high performance open source micro-architectures' is just an assumption.

Re:Arm kills off its anti-RISC-V site after own staff revolt by Nokinside on Wednesday July 11, 2018 @10:14AM (#17507068)
Yes you have. It's completely different to design small volume ASIC chip with RISC-V processor and high volume microprosessor core that is cost effective.

Processor initiative in EU and India have are providing R&D money for basic research and competence building for local companies. They will be customers, not manufacturers.

Re:Arm kills off its anti-RISC-V site after own staff revolt by nickik on Wednesday July 11, 2018 @01:32PM (#17508688)
The EU and India will both build actual chips and those can be tapped out. They will also of course consume their own stuff.

There are startups like Esperanto and many university groups and open source who are all interested.

Of course you still need to find costumers for a mass tapeout, but once the whole linux tool-chain is running there are lots of potential applications and costumers.

Re:Arm kills off its anti-RISC-V site after own staff revolt by lkcl on Wednesday July 11, 2018 @08:31PM (#17511336)
> You won't see high performance open source micrarchitectures that implements RISC-V core.

India's Shakti Core is a 6-stage pipeline that runs at 2.5ghz in 20nm and uses only 120mW. Their roadmap includes VLSI variants which will piss all over ARM and Intel, which is funny because the India Goverment has given them unlimited resources and backing to do exactly that.

All entirely libre-licensed... starting here: https://bitbucket.org/casl/