Hacker News Reader

Comment by bit_logic | Hacker News Reader

Maybe this rumor is only half right and it isn't what everyone thinks it will be. Instead of replacing x86, what if it's just Apple adding their ARM chip to the laptop? Basically just take the current MacBook and stick a iPad ARM chip in there. And maybe make the screen a touchscreen too. It would make iOS development much closer to the real thing. And for non-developers they can run iOS apps natively. So you get a Mac that can run both x86 and ARM natively. But if you try to use more iOS (ARM) apps you get really long laptop battery life since it's optimized for that. And x86 is there when you need to run more power hungry applications. Seems like the best of both worlds in a single laptop if they do this.

View on HN

Adding significant BOM cost, growing physical volume, reducing battery life, creating lots of complexity to get certain apps to run on one CPU or the other and the associated cache coherency issues? So that iOS developers can test their apps on a native CPU (But still plenty of differences like screen size, no cell radio, no GPS, accelerometers, etc) Seems dubious.

All Macs already have an ARM chip inside them in the form of the T2 chip.

But that’s specifically for Secure Enclave work (disk encryption, biometric data). I don’t think they’d want to risk someone running arbitrary code there and breaking the sandbox. (The SEP is also separate from the A-series chip in the iPhone for a similar reason, IIRC).

In addition to the secure enclave, they already have an A series core on there. That's what runs the touch bar.

There's a full XNU based OS on there called "BridgeOS" that's in the iOS/tvOS/watchOS family.

Open System Information → USB on a Mac with a T2 chip and check out all the stuff attached to it.

So do all AMD Ryzen CPUs in the form of TrustZone/PSP, usually a Cortex-A5. It's equally as user-inaccessible as the T2.

There are probably a dozen ARM chips, e.g. WiFi module, battery controller, touch bar, etc

I seem to remember Dell doing something like this a number of years back -- an x86/ARM windows/Linux hybrid. The idea was that you could boot instantly into a Linux/Arm system, do things like take notes and email and get good battery life, and boot into Windows only when needed. I don't recall if it was just a concept or if it was eventually sold.

It shipped https://en.m.wikipedia.org/wiki/Latitude_ON

People thought Apple might be do the same thing when converting from 68K to PPC and PPC to x86. Apple would never do it.

However, there were PPC upgrade cards for 68K Macs but you had to reboot to switch from 68K to PPC.

Reply on news.ycombinator.com