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Comment by quanticle | Hacker News Reader

Using PPC in a laptop form factor is a really confusing choice, given that Apple abandoned PPC [1] in their laptops for Intel because they judged that there was no way that IBM was ever going to come out with a PPC chip that was ever going to be as power efficient as the comparable Intel parts. Their "Why PPC" page [2] makes no mention of power or thermal efficiency, and just states that PowerPC is better because the original version of the ISA was invented after x86 and ARM. By that logic Itanium is the best ISA of all!

[1] https://indianexpress.com/article/technology/opinion-technol...

[2] https://www.powerpc-notebook.org/why-powerpc/

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Many, myself included, would gladly take a major hit in battery life if it means having a machine we can actually trust.

Trust means no ME backdoors, no random blobs which can be supply chain attack vectors.

Freedom means I can do anything I want to the software and firmware and repair anything as needed long term without the consent of a corporation that has a financial interest in seeing their hardware go to a landfill in 2 years so people buy the latest.

How does the open/libre/trustworthy potential of PPC and Power products compare with RISC-V? Current, and near future?

This is something I've been wondering. It's started looking like there will be a lot more hardware options based on RISC-V. Thus far, PPC/Power has had better libre options due to: https://www.raptorcs.com/ I hope there will be healthy competition from open/libre/trustworthy and performant RISC-V boards.

> open/libre/trustworthy potential

It's not just potential but actual: Those Raptor workstations and servers already have coreboot firmware and run Linux (and whatever BSDs run on PPC today.)

Agreed for current, over recent years. But what about near-future, with multiple sources of performant RISC-V CPUs? And will a larger variety of boards follow, possibly including very libre ones like Raptor does for Power?

I don't want to put words in the mouth of who you are responding to, but here would be my assumption. PPC is probably in a better position for mass distribution in the short term. Where as RISC-V still has some time to go before we can get there at modern performance in a package that goes in consumer hardware. Also, just have more architectures means more possibilities of design decisions and more choice, which is always good.

Could you please point at a source of currently available performant RISC-V CPUs, something comparable to Intel's lower-end mobile chips like, say, Intel i3 from 5-7 years ago?

I used to think that current RISC-V offers are approximately in the ARM A57 league.

Unfortunately with POWER10, a couple of blobs are required, so Raptor are sticking to the older POWER9 for now.

I saw, I saw. I hope that changes. Maybe someone can reverse it, or pressure IBM (ha!)

What's even more confusing is their choice of parts. The NXP QorIQ line is designed for use in networking hardware, not in mobile devices -- it has limited power management functionality, and, as best I was able to tell when I looked into this last year [2], has idle power consumption somewhere around 7W, ramping up to 20W under load. It's not especially fast, either -- it's only got four cores at 1.8 GHz. Most new cell phones will run rings around it.

My best guess is that they somehow decided on the PowerPC architecture before evaluating what parts were available, and realized too late that nobody makes mobile PowerPC SoCs...

[1]: https://www.nxp.com/products/processors-and-microcontrollers...

[2]: https://news.ycombinator.com/item?id=24188796

Indeed, they must have decided on the Power architecture first, because it's available and can run without proprietary binary blobs. That was the key consideration, I think.

Otherwise picking an Intel or AMD part would be much more efficient from many angles.

> because it's available and can run without proprietary binary blobs

Which isn't even necessarily true. The POWER architecture is just an ISA. It doesn't specify anything about how the rest of the system works.

(The POWER Architecture Platform does exist, but, as far as I know, it's only used in IBM's POWER servers.)

Conversely, it's hardly as though POWER is the only architecture this is true of. Coincidentally, NXP also sells a line of ARM SoCs (the i.MX line) which can be used in a blob-free mode, and there are already several open hardware laptops built around those parts!

Fully agree, but at the same time I'm hard pressed to think of an alternative that doesn't need binary blobs to bring up & is better in terms of power usage / efficiency.

Most modern chips really can't initialize themselves anymore without feeding them some blob, most frequently for DDR controller calibration but also sometimes SERDES bits.

That said I'm not sure why this should be treated harsher than if the same code were burned into a mask ROM on the chip. The latter case would be acceptable for "blob-free open hardware enthusiasts". It's a rather arbitrary distinction IMHO.

add.P.S.: my personal goal would be a system where I control 100% of all running code starting at the bootloader. Most of these initialization blobs are one-shots, e.g. push the appropriate electronic parameters into some high-speed analog block. But this means no Intel ME & no AMD PSP, please. It also means no "power management" coprocessor (reasonably common on ARM SoCs), not even due to openness or trust concerns but rather because I've been bitten by bugs in those… :(

The team is also looking for donations to obtain 55W MXM-A cards. It would be nice to have a proper GPU, but is there a reason why it can't be a random SXGA-compatible framebuffer or some FPGA IPs? Is this laptop being designed for some specific task?

I wouldn't think that PowerPC is ill suited for reasonably low power designs. It is a RISC chip after all. And up to and including the G4, they ran very well in the Apple laptops. Only the IBM-made G5 was a very hot beast, perhaps because it pushed the cpu frequency beyond the comfort zone for its process in the attempt to keep up with Intel. But a fresh design with a modern process could yield very low power and still well performing chips. Even the Itanium, which had a reputation for being power-hungry probably would be efficient enough to be used in a smart phone, if ported to the TSMC 7nm technology.

A ton of ARM designs are RISC chips, because ARM stands for Advanced RISC Machines.

Somehow they power nearly 100% of mobile phones, and various other mobile devices.

Yes, of course, all ARMs are RISC chips. That is why I think a reasonably designed and manufactured PowerPC should have similar power and performance characteristics.

Apple has since moved off of x86 for similar reasons. The issue is the fab process more than the architecture.

They are not aiming for the "ultrabook" form factor, but rather the mobile workstation form factor.

According to the leaflet from NXP, the CPU has a "typical" power consumption of ~15W - if that means under load, it would be in the ballpark of Intel and AMD mobile CPUs, as far as I understand.

Because Open hardware.

I figure someone might as well go whole-hog on that and build a PC with just a big ol' FPGA.

Fpgas are very unsuitable general purpose computers. De10 nano is a very beefy fpga and can barely play doom acting like a general purpose 486 and lacks a fpga

Oh well, I figured that a PowerPC Notebook was for hobbyists.

What I would find fascinating is to think about languages and OSs for FPGA and try to break loose from the utterly boring C/Unix/68k,x86,MIPS,blah paradigm. Having something turnkey with attachment to various ports and a display would be kind of cool. Maybe that exists already.

I worked on a project with a processor-on-an-FPGA and while it wasn't fast, the video codec in FPGA made it useful. Kind of a neat thing I think.

Ppc notebook is a thing because ppc has been “open sourced” so you can just make ppc chips using great documentation with nobody knocking on your door. As a technology it’s dead as a door nail but it’s free as speech.

That is being done too for when trust REALLY matters.

See the Precursor.

FPGAs are incredibly closed, outside of Lattice Semiconductor's tiny FPGAs (unsuitable for computers). In all practicality for "openness", any open-source advocate should rather use Intel/AMD than Xilinx/Altera.

Closed-source synthesizers, closed source bootup, closed source loaders, etc. etc. You're pretty much trusting the FPGA software more than any CPU.

> In all practicality for "openness", any open-source advocate should rather use Intel/AMD than Xilinx/Altera.

That's an ironic comparison to make -- Intel bought Altera in 2015, and AMD is in the process of acquiring Xilinx.

Between the two, though, there's been a lot more work done on open toolchains for Xilinx FPGAs.

oh, bummer. So you'd need a clean tool chain too.

If they went for a NUC/Apple Mini form factor that would have been an interesting (and easier) first try: A meaningful difference from Talos, yet a less restrictive power budget than laptops.

I am surprised this is the most upvoted comments.

Energy efficiency of a chip has relative little if not close to zero relation to the choice of ISA in PC usage. Apple moved to Intel because of Fabs and uArch design choices.

People may want to explain why you downvote?

Both Pentium 4 and Pentium M are x86? What has the ISA got to do with it? Seriously? Intel had the Fab advantage at the time, and IBM didn't want to design Laptop based computer chips. It was as simple as that. It has nothing to do with PowerPC incapable of making energy efficient chip.

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