Rise of the ARM Clones

An anonymous reader writes "Clones of the ARM processor intellectual property are again becoming available for free from the open source hardware community. ARM was rigorous in shutting cloners down in the past but the clones are rising again under codenames Amber, Storm and Atlas, albeit of older instruction set architectures."

Comments

Rise of the clones

[Kopachris]

You can finally have your very own clone ARMy.

Why not?

[hairyfeet]

Personally I'm more interested in some of the MIPS chips like the Loognson Dragon that has built in X86 hardware acceleration, supposedly you get 80% of X86 speed when it comes to emulation but while having the longer battery life. Sadly we'll never see it in the states thanks to IP laws but if the chip designed were truly opened up I bet we'd see all kinds of new ideas and approaches. Remember when we had choices in X86 besides AMD and Intel? They had chips like WinChip that were more of a RISC design, you had more media leaning like Cyrix, it gave us a wealth of choice and if that happens with the ARM clones I'm all for it.

Re:Why not?

[JDG1980]

You actually miss Cyrix?

Re:Why not?

[jones_supa]

Apart the crappy thermal solution, what kind of problems did you have with the Cyrix CPU?

Re:Why not?

[unixisc]

Personally I'm more interested in some of the MIPS chips like the Loognson Dragon that has built in X86 hardware acceleration, supposedly you get 80% of X86 speed when it comes to emulation but while having the longer battery life. Sadly we'll never see it in the states thanks to IP laws but if the chip designed were truly opened up I bet we'd see all kinds of new ideas and approaches. Remember when we had choices in X86 besides AMD and Intel? They had chips like WinChip that were more of a RISC design, you had more media leaning like Cyrix, it gave us a wealth of choice and if that happens with the ARM clones I'm all for it.

I'd argue that we have a bonanza/plethora of choices as far as ARM clones go - you have them coming from Phillips, TI, Qualcomm, Freescale, Marvel, NVIDIA, Atmel and who knows who else. These are all licensees of ARM Holdings. Similarly, MIPS has/had its many licensees. Intel was more restricted, and I'd argue that it was for a worse CPU.

If you are thinking about an open CPU, a good one would be OpenRISC/OpenCore. Currently, it's a soft CPU, which any company could pick up, license and fab. So all sorts of great stuff could be done w/ such a chip. However, the people w/ the skills to make it run long on a battery, or make it fly would probably be working for one of those chip designers, which has little to gain by opening up their designs. Open source hardware is a great concept, but just falls flat on its face when the rubber meets the road.

But the current x86 IP trump card lies in the hands of AMD, and I think that they probably would have a better future if they continued manufacturing just the ATi GPU, while licensing the x64 design to anyone who's interested. As is well known, nobody can compete w/ Intel on its fabs, so it's pointless for AMD to even try. But if they were to do what ARM Holding does, and license the x64 design to anybody who's interested, and let anybody - Apple, Freescale, NVIDIA, et al license it and make CPUs and sell it, it should make AMD a bundle, keep the company afloat, but not have to deal w/ manufacturing headaches that it's always been ill equipped to deal with. Then you could see a company come out w/ a multicore CPU - 2 AMD64 cores, 2 ARM cores and anything else that they fancy. Maybe something that can natively run both Android and Windows apps.

Re:Why not?

[xanclic]

supposedly you get 80% of X86 speed when it comes to emulation but while having the longer battery life.

Actually, it's rather x86 applications run at about 80% the speed of native MIPS applications.

What restrictions apply to CPU architectures?

[JDG1980]

ARM will license out their cores to whoever pays. Intel and AMD (and Via, but no one cares about them) are apparently the only ones allowed to make x86 chips. But what type of "IP" is relevant here? What is the legal basis for the restrictions? If someone decided to make their own x86 clone, for instance, what would they be violating? It can't be trademarks, since that could be circumvented simply by changing the wording on the product and literature. I don't see how it could be copyrights, unless the implementers actually copied the original die mask or made a derivative work of it. So that leaves patents. Can you patent opcodes? Or is it only specific methods of implementing the opcodes that are covered by the patents?

The original Intel Pentium was released in March 1993. This means that the patents on it should either be expired or nearing expiration. Would there be any demand for an open implementation of a 20-year-old x86 CPU? In embedded systems, maybe. And as more time goes by, a greater and greater portion of the x86 ISA could be implemented.

Re:What restrictions apply to CPU architectures?

[DuckDodgers]

From the second to last paragraph in the article, "It is the case that patents usually have a 20 year life and therefore those that were in force in 1990 have now expired. However, modern implementations of old instruction sets could infringe on techniques that have been patented more recently by ARM or other companies – so I don't think the age of the instruction set is a water-tight defense."

Re:What restrictions apply to CPU architectures?

[JDG1980]

and if they do, ARM is the much more logical choice. Better energy profile...

This assumes you care only about battery life and not performance. x86 platforms have always outperformed ARM platforms on a clock-for-clock basis, and probably always will, since the CISC instruction set allows more work to be done per cycle. And on a modern CPU, the decoder that converts x86 instructions to internal micro-ops is a tiny portion of the die space, even on portable devices.

Meanwhile, Intel still fakes efficiency figures by putting the power-hungry parts of the Atom into its north-bridge. And people still fall for it, despite the shitty battery life.

Your information is years out of date. The first Atom CPUs were paired with an old i945 chipset, which did indeed use far more power than the CPU itself (the chipset had an absurd TDP of 22W, compared to 2W-4W for the processor itself). In 2009, however, Intel moved many of the functions into the CPU and stopped producing the chipset on such an outdated process, and this dramatically reduced TDP to low single digits. Yes, you still have to add the PCH+CPU to get total TDP; anyone who doesn't realize this shouldn't be trying to design an embedded system. The upcoming new generation of Atoms (Silvermont) will be full-fledged SoC designs with no need for a PCH. They are expected to have considerably better performance and lower power consumption. And the truth is that the existing Atom design is really bad, and was in part designed that way to avoid cannibalizing sales of Intel's more expensive desktop CPUs. But with the mobile device market being what it is now, Intel can't afford to hold back any more.

Re:If APIs can not be patented

[jellomizer]

Because it isn't abstract.

Do it in China

[rodrigoandrade]

They have the manufacturing ability and steamroll over patents, trademarks, intellectual property, etc.

Really, was that so hard??

So it's basically a GBA-era ARM chip without thumb

[Dwedit]

The article mentions that it is compatible with the ARMv2a instruction set, though it may not be implemented the same way regarding pipelining and caching. The ARMv2a instruction set is basically the same instruction set as the ARM7TDMI, but without THUMB, and without the BX instruction. Any pure ARM code that doesn't use newer features (such as saturating arithmetic) should work on it fine. GCC should support this with no problems.