Felix86: Run x86-64 programs on RISC-V Linux

by rguiscard • 1 year ago

126 32 1 year ago

What remaining challenges are you most interested in solving for felix86—GPU driver support, full 32-bit compatibility, better Wine integration, or something else entirely?

westurner• 1 year ago

The felix86 compatibility list also lists SuperTux and SuperTuxCart.

"lsteamclient: Add support for ARM64." https://github.com/ValveSoftware/Proton/commit/8ff40aad6ef00... .. https://news.ycombinator.com/item?id=43847860

/? box86: https://hn.algolia.com/?dateRange=all&page=0&prefix=false&qu...

"New box86 v0.3.2 and Box64 v0.2.4 released – RISC-V and WoW64 support" (2023) https://news.ycombinator.com/item?id=37197074

/? box64 is:pr RISC-V is:closed: https://github.com/ptitSeb/box64/pulls?q=is%3Apr+risc-v+is%3...

JonChesterfield2• 1 year ago

Haven't found the source code (https://github.com/orgs/felix86-emu/repositories looked likely but no), curious whether this is a qemu fork or a DIY effort.

drmpeg• 1 year ago

https://github.com/OFFTKP/felix86/

JonChesterfield2• 1 year ago

Nice, thanks! I appreciate seeing a bunch of the instruction definitions written in a serialisation format (e.g. https://github.com/OFFTKP/felix86/blob/master/counts/SSE2.js...) as opposed to C macros.

guerrilla2• 1 year ago

This is good. Maybe it means some day we'll able to run Steam on it. Wouldn't that be funny? Windows emulation on x86-64 emulation on RISC-V.

snvzz• 1 year ago

I am hopeful valve will release a risc-v build themselves.

And wine/proton will integrate with this or some similar solution for running x86 binaries.

guerrilla2• 1 year ago

They can't. The games themselves are compiled for x86-64 and closed source. It's not enough if they just recompiled Steam, Proton, etc.

OptionX2• 1 year ago

Always wondered why RISC-V doesn't get more mainstream adoption.

Even if not at the consumer level, having your data center, for example, running a cheaper (I assume since no license for the instruction set means not having to pay for it and more options to buy from leading to lower prices) and less power demanding option when compared to x86-64 sounds enticing to me.

Maybe no one wants to be the genea pig to iron out the kinks of the transition or maybe the raw performance of x86 is bigger deal than I think it is and its worth the price and power. Dunno.

bobmcnamara• 1 year ago

Always wondered why RISC-V doesn't get more mainstream adoption.

For me, it's because the ecosystem has fragged even harder than Xtensa, who will sell you custom CPUs. THead made yet another vector unit that's required to approach anything near the Intel/AMD moat numbers.

SpecInt/GHz last year was around half of Intel/AMD/ARM numbers.

The imminent demise of CISC has been trumpeted from the rooftops for at least the last 30 years...

deaddodo2• 1 year ago

ARM isn't CISC and has, by sheer numbers, completely dominated x86 for decades now; not counting the massive number of MIPS, AVR, etc embedded chips.

Additionally, if you want to get super technical (as if there were ever a real delineation between RISC/CISC), both AMD and Intel decode x86 into internal micro-ops which are essentially RISC.

So, for all intents and purposes, CISC is dead and buried.

Kampfschnitzel• 1 year ago

From what I've seen, most RISC V chips are still far behind x86 and ARM when it comes to raw power. I don't think the loss in performance is justifiable with lower cost (yet)

choffee• 1 year ago

I think there has been a big uptake in things you don't see like embedded or FPGA cores but as a general CPU it's nowhere near as efficient as ARM/x86 right now is my understanding. So it might be running in the SSD and the Fan controller but not as the CPU. I think a large part of the cost of a CPU core is not the instruction set but the optimisation of the CPU and ARM/Intel/AMD are still way ahead in those. And so it needs people to optimise the cores, which when they have done that they charge for being a better CPU.

rwmj2• 1 year ago

There's a fair bit of adoption where you don't see it (for example, if you have an NVidia GPU or a WD hard drive, you likely have a few embedded RISC-V cores already). We're expecting server hardware with good performance in a year or two.

brucehoult2• 1 year ago

Always wondered why RISC-V doesn't get more mainstream adoption.

It's very simple!

Because the amount of time it takes to design and produce a data centre level CPU microarchitecture is greater than the time RISC-V extensions needed for data centre CPUs have existed.

The original RISC-V specification was ratified less than six years ago, but you really couldn't create a data centre CPU until at least RVA22, ratified two years ago in March 2023 -- or preferably RVA23 which was ratified in October 2024 and has the features needed for efficient hypervisors.

You can knock out a microcontroller CPU core in a weekend, but something to compete with current Apple, AMD, Amazon etc CPUs takes a long time to make. Most companies doing that started work only in 2021 or 2022.

It is simply too soon. A lot of stuff is in the pipeline.

OptionX2• 1 year ago

Makes sense. There's always value in a maturity of a system especially in the enterprise world.

junon• 1 year ago

They're significantly slower than x86 and ARM at the moment.

usrusr• 1 year ago

What fraction of the total cost of operating a datacenter do you suppose goes into ARM licensing? That's how much more efficient than RISC-V an ARM would have to be in order to make it the preferred CPU in a "we don't need x86" scenario. That's a very low bar to clear (for ARM, not for RISC-V)

Veserv2• 1 year ago

Any price advantage, even if we assumed a fully mature ecosystem with equivalent processors and systems available, is massively overstated. ARM had a total revenue of just ~3.7 G$ in 2024 over ~29 billion chips [1].

In contrast, Qualcomm, just one of many large suppliers of ARM-based systems, had a total revenue of ~39 G$ and a operating income of ~10 G$. ARM's entire revenue would easily fit into Qualcomm's profit and only increase costs by ~12%. And that is just one supplier. You have Samsung, Apple, Broadcom, Google, Amazon, Nvidia, TI, NXP, etc. to help round that out.

The total impact of ARM licensing and IP costs is almost certainly less than 1%. And given that RISC-V does not currently have a fully mature ecosystem, you get to trade that for a 1% cost improvement; not really a winning strategy right now.

It is likely the main advantage in the long run for RISC-V is that not requiring a license might enable a more vibrant ecosystem due to removing the licensing barrier which might enable better designs at comparable costs (because, again, the cost differential should only be on the order of 1% in the long run) rather than just creating comparable designs that just chip off the licensing cost. That or RISC-V could win because the giant manufacturers feel like putting the squeeze on ARM to drive 1% off their BoM.

[1] https://www.acquired.fm/episodes/how-arm-became-the-worlds-d...

gary_0• 1 year ago

Using 2024 numbers for ARM might not give a clear picture, because that was many years after major companies like nVidia and WD already switched all their major internal chips to RISC-V. ARM's lunch was already partly eaten; many billions of RISC-V chips were already in the wild in 2024. And companies like Tenstorrent have been building high-performance stuff on RISC-V for a while. If Jim Keller thinks RISC-V is worth it, the advantage must be worth more than 1%.

RetroTechie• 1 year ago

It's mostly a matter of time. @ This point RISC-V is well beyond critical mass (read: it's here to stay), and the ecosystem is growing fast.

But designing complex IC's, getting those into products ("design wins"), selling those products, software support etc, all takes time.

For example, came across this list recently:

https://en.wikipedia.org/wiki/List_of_common_microcontroller...

(note: it will be far from exhaustive. On the low end, uC architectures are like water in the ocean. Some are just more popular than others).

Many of the products those arch's go into, have 10y+ production & support lifecycles. Change comes slow there.

I suspect that over time, RISC-V will mop up a good portion of that list (for those entries still in production), and become a go-to default choice for maaany applications. Where a designer would need good reasons to not pick a RISC-V based part. Not unlike how low end Cortex-Mxx seem to be everywhere these days.

Higher up, licensing is only a tiny % of overall costs. (Peak) performance, GFLOPs/Watt etc is what matters. RISC-V is still (somewhat) behind the curve there. Which isn't surprising given how much engineering & optimisation has gone into x86 & Arm over the years.

But being a shared/open architecture, may open new doors. For example: right now, highest-performing parts are always closed (commercially licensed IP cores. And/or manufactured in-house).

For RISC-V otoh, it's entirely possible that at some point, the highest-performing cores are open source ones. Not saying that'll happen! But it's possible.

If so, eg. Arm could only match that by open sourcing their latest & greatest. Which ofcourse would evaporate their business model.

So the licensing alone could have RISC-V go places where proprietary IP cores can't go. Exiting times...

Edit: but issue below also applies.

https://xkcd.com/927/

ValdikSS• 1 year ago

How's it different from box86/box64? It also has RISC-V with JIT support.

https://box86.org/

sylware• 1 year ago

Funny, I am doing exactly the other way around: I run small RV64 linux programs on x86_64 linux.

I cannot way for the first AAA games to run on ultra-performant RISC-V(RV23+) microarchitectures made with the state-of-the-art silicon process.

gitroom• 1 year ago

Love that folks are hacking stuff like this already, even if RISC-V still feels ages behind x86 for anything heavy. I def wanna see how far these emulators can actually push things. Kinda makes me hope for that wacky Steam-on-RISC-V future lol.

_joel• 1 year ago

Almost heh https://www.reddit.com/r/RISCV/comments/1jfkng6/windows_stea...

Felix86: Run x86-64 programs on RISC-V Linux

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