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by ClassyJacket 3427 days ago
Interesting. The article says that Apple is considering an ARM co-processor, not a replacement for the Intel CPU.

I have no doubts at all that Apple have at least had extensive internal discussion and testing about this. In fact, I believe they've probably done extensive internal discussion and testing about replacing the Intel one altogether, but can't get there yet.

It'd give Apple more control over their device design and release schedule, potentially lower power consumption, and straight up more profit via vertical integration.

Like the PowerPC transition, they could come up with a new Rosetta - which was the emulator that ran old PowerPC apps on x86. Microsoft has recently demoed x86 apps on ARM, and I'm sure Apple could do the same.

As far as I know there's no fundamental reason ARM processors can't be as fast as x86 ones, they just haven't been targeted for those kind of devices yet - but I'd be happy to be corrected by any CPU experts. And with Apple's success in the mobile processor space, I have no doubts that if anyone could pull this off, it'd be them.

So what's holding them back? Thunderbolt. They've gone all-in on that already - touting as the future of high speed external devices, and giving the MacBook Pro nothing but four Thunderbolt enabled USB-C ports and a headphone port. But Thunderbolt is an Intel property, only available on their CPUs.

The 12" MacBook already doesn't have Thunderbolt (the MacBook Pro does), but it feels like with software compatibility, this would be an all-or-nothing thing. I don't see Apple continuing to sell both x86 and ARM machines on an ongoing basis. So how would they get Thunderbolt into the MacBook Pro?

Having a co processor to handle PowerNap would allow them to take a small step in that direction without losing Thunderbolt or having to develop a slow x86 emulator. They could even offload other parts of the OS to the ARM cpu, freeing up the main CPU for other software, and to go into low power mode more often.

3 comments

That's actually a interesting point - I wonder if it's possible to license the Thunderbolt tech in some way, and have it hooked up to the ARM Chip; something like what Asus does to give AMD thunderbolt: http://www.eteknix.com/asus-give-am3-boards-thunderbolt-supp...

Saying that - and I hope someone corrects me here if I'm wrong, I was under the impression that Apple & Intel jointly created Thunderbolt (or perhaps it is an Intel only tech), which means Apple may have some sway here.

Just thinking about it more - Thunderbolt is just a protocol driven over USB-C now, so I'm fairly certain USB (3/C) might eventually be able to cover everything Thunderbolt does, or apple takes their "lightning" protocol to replace Thunderbolt, and use that over USB instead of Thunderbolt over USB.

Just musing but it is a very under appreciated aspect to all of this as well!

I almost posted that link too, but according to this comment, that product was cancelled and never released because Intel refused: https://www.reddit.com/r/Amd/comments/539kvq/will_amd_cpusmo...

There's still a mention of an expansion card on their site:

https://www.asus.com/us/Motherboard-Accessory/ThunderboltEX-...

But it's only compatible with ASUS motherboards that already have Thunderbolt. So I'm not sure what the point of it is (just to upgrade from ThunderBolt 2.0 to 3.0 maybe?), and as far as I can tell... still requires intel.

So as far as I'm aware, no product has ever released with Thunderbolt that doesn't use an Intel CPU (and even then, only higher-end ones).

Licensing aside, it may be a technical issue - ThunderBolt is an extension of PCI-express, which just isn't part of the ARM design. I'm not sure how feasible it would be to add it.

Plenty of ARMs have PCIe, maybe even the A9.
Any examples?
Nvidia Tegra, all server ARMs, all Wi-Fi APs, higher-end embedded SoCs (e.g. Marvell), etc.
Interesting. I didn't know that.

However, that still doesn't mean Intel will certify anything for Thunderbolt that doesn't use their processors. I still haven't seen any evidence of a certified Thunderbolt host device existing that doesn't have an Intel CPU.

The Freescale(now NXP) i.mx6 has four lanes of PCIe. All that's required is a peripheral on the main memory bus.
This is actually an argument in favor of USB-C, since it's likely that faster versions of the standard will overtake Thunderbolt in the future.
There will be a Thunderbolt 2 which stays a few steps ahead by then.
It always seems a bit like Bluetooth to me, as in "this next version is going to be great."
They're already on Thunderbolt 3.
Who said they won't ditch Thunderbolt in the 3-4 years t would take for ARM Macs to take off? Who says they won't use USB-C? They don't even make Thunderbolt peripherals anymore