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I think he's kind of speaking past the original author. The original piece is basically about how the author doesn't think that RISC-V will take off outside embedded, because of some design decisions that lead to poor performance compared to ARM64 and because so much of the ISA being optional means that there's too much fragmentation to make binary distribution feasible. Meanwhile, this piece is mainly about how RISC-V is great for embedded because companies can build it into custom chips with specifically the functionality they need, and because of how cheap it is for low-end use cases since there's no license fees.

The only real point of contention I see between the two is that this piece goes on to talk about how it's a selling point that RISC-V can be used for both low-end 10 cent microcontrollers, and high-end multi-core processors running Linux. Personally I don't see the benefit of this since you're going to have to recompile your software anyway, and since all the RISC-V SBCs I'm aware of have significantly worse performance and efficiency than comparably priced ARM SBCs.

He says:

> From that position, the difference between a ten cent part and a one dollar part is not a rounding error and it is not a detail you get to wave past on the way to the interesting discussion about encodings

Yet earlier:

> I pay anywhere from US $60 to US $200 to ship one dollar chips that people everywhere else get free shipping on

Seems to me that the difference between a 10c chip and a $1 chip are a rounding error when the shipping cost dominates so much?

I love the article, it's a breath of fresh air compared to the usual bay area centric takes. However there's just one issue:

> The students I want to teach are in the same position, and so are the ones in Nigeria and Bangladesh

It does not take $60 to ship small sub $1 chips from Asia to Nigeria/Bangladesh. These two countries are all on global trade routes (both supply and demand) and the expensive last mile delivery costs are fairly low there too.

I don't think the Author disagree with what the original article wrote. If anything everything he said seems to reassert what the original article intended to state.

And while things has died down a lot in the past few years, there is a reason why I wrote the line.

"You do not criticise The Rusted Holy Grail and the Riscy Silver Bullet."

[delayed]

Working archived copy - https://archive.is/9FaRC

Nice read!

Though it feels a bit strange that "I have exceeded the allowed number of requests. (500 times)" when I first clicked the article and I'm pretty sure I don't share the ip of my self-hosted VPN with anyone.

My perspective using Nix is that it's hardly worth standardizing ISAs. Recompiling software is easy and we should have a Cambrian explosion of different designs.

This is especially good if one scopes out a family of ISAs that are ABI compatible such that one can compile down to a semi-pre-optimized portable IR, and just do the last bit per ISA.

To me it feels like the difference in positions is "this could be made better" vs. "but this is already so much better than before". Both are right.

Maybe I'm missing something important so far...

This is the sort of content I endure this place for. Thanks for posting.

Absolutely hugged to death.

"Now price the same journey on the other side, forget x86-64 and that duopoly, patent minefield, with multi-thousand dollar debug probes; we'll take a look at ARM."

The 386 and 486 patent should have expired more than 20 years ago. No one tried to open source it. https://github.com/EI2030/Low-power-E-Paper-OS/blob/master/0... There were many companies that had clones in the early 90s, and I wonder whether any of them still have the rights to manufacture them.

" That is a better reason than elegance. and I want to tell Mr Grinberg, that the word priviledge he tosses around in his article also extends beyond the ISA depending on where you are in the world."

Grinberg is an emigre from Ukraine, which isn't the most privileged place in the world. In fact his research articles go deeper than the average software developer in Silicon Valley.

Original HN discussion referenced:https://news.ycombinator.com/item?id=49298035

I have no idea what's going on here, but the title alone gave me second-hand engineering stress. Solid post.

That is just an amazing website and initiative.

https://rvembedded.com/products/project-lab/

Definitely interested!

"Rate Limit Exceeded"

Does anyone have an archive?

The author of the article just got a fan.

Some serious stuff he builds on top of those chips.

This blog post is very defensive and argumentative, which I guess is fair considering Dmitry's post is similarly inflammatory, but most of it was really not convincing:

> Simply put, the things a high-end CPU needs are diametrically opposed to the things a small cost-saving microcontroller core needs.

> The conclusion he draws is that no single ISA can serve both ends, and that RISC-V fans are fooling themselves, in theory the premise is true. The conclusion does not follow, and I can show you why from three parts sitting on my desk as we speak.

> CH32V003. This is the cheap "RV32EC" with sixteen registers, no multiplier, no divider, machine mode only,

> CH32H417. A dual core MCU that is unmatched in performance to price point and is at the higher end of the MCU line

> Baochip. A VexRISC-V with an MMU built around a stack thats open from silicon to os Baochip-1x: A Mostly-Open, 22nm SoC for High Assurance Applications

Uh, which one of these is a datacenter server cpu? Or a workstation cpu? Or at least a developer laptop cpu? How about a Raspberry Pi 4 level SBC (supporting latest ubuntu and fedora releases, driving a display that runs a browser and plays video ...)

There's a lot of angry indignation but it seems obvious that Dmitry is quite right about this.

But I found this is where this blog post starts making a lot of sense:

> Has anyone tried adding an MMU to a Cortex-M? The physical tradeoffs are real, the difference is that with RISC-V, the ISA owner does not decide for you where that boundary must be drawn. If you want virtual memory on ARM you license a Cortex-A instead, which is a different core family, a different profile, a different negotiation, and a different royalty.

> Compare what happened with Baochip. The RISC-V privileged specification defines supervisor mode and Sv32 paging as optional things an implementation may provide. VexRISC-V is an open core, somebody added an MMU to it. bunnie built a chip around it and runs a microkernel with real process isolation on it

Yeah, that is a good point. We're still in the low-end specialty realm, but that is real interesting advantage for RISC-V, a good reason for it to exist.

As for shipping to Trinidad and Tobago ... this post is trying too hard to turn this into moral issue, but it seems a bit random (OrangePi cost $30 and shipped free? you can also get arm-based and stuff from the same places), and the vast majority of people don't live on semi-remote islands, it doesn't make sense to consider this kind of accessibility above all else, and it's strange to blame Dmitry for not thinking of you here.

More than half the article is AI slop. Sad.

Just an unlucky spawn point. We need to focus on ourselves. "oh no shipping to some remote island is expensive compared to NYC that has next day free on everything" Well, duh.

yo this is actually some really fire reading. i had to read it twice then go back and read the original that he's responding to here. i feel full of wonder right now seeing people who are this deep into compsci debating merits in the marketplace of ideas, there's just so much going on globally with computing that i never even get to see. super fascinating to read about the different constraints at play here even the global socioeconomic ones and how they apply to the chip world in general. it sounds like risc-v's real play is democratizing access to the entire embedded stack