Apple posts ARM-compatible source code for XNU kernels in iOS & macOS

Posted:
in iOS
Apple has silently released ARM-ready source code for the XNU kernels found in iOS and macOS, marking a first for iOS, and possibly showing off some of the groundwork for Macs with ARM-based processors.




The code is available through a GitHub repository. While exposing some of the operating systems' internal architecture, many proprietary elements -- such as apps and frameworks -- are of course absent, and Apple's kernels are being offered under a more restrictive license than some other open-source projects, such as most Linux distributions.

All of the Apple A-series processors in iPhones, iPads, iPods, and the Apple TV use ARM-based designs. Macs have depend primarily on Intel processors since 2006.

Recent rumors have claimed that Apple could be designing its own ARM-based CPU for future Macs in an attempt to reduce its dependence on Intel. While Intel chips are generally regarded as powerful, the company puts out CPUs on an independent schedule and doesn't specifically optimize them for Mac hardware.

ARM-compatible kernels aren't necessarily a sign that a transition is imminent, or even planned. MacBook Pros already use one Apple ARM chip, the T1, to run the Touch Bar and Touch ID. The company has also made it a tradition of having code ready for alternate architectures -- that policy helped the company make its original switch to Intel faster than expected.

There could be several potential complications with a wider ARM transition, such as Boot Camp, which lets Macs run Windows through a separate partition. Microsoft is however working on ARM compatibility for Windows, which might smooth out some issues.

Comments

  • Reply 1 of 18
    xzuxzu Posts: 139member
    Hoooooray!!!!! I still need Intel Macs for work though. A consumer ARM chip would be cool.
    schlackrepressthiswatto_cobra
  • Reply 2 of 18
    tipootipoo Posts: 1,058member
    Either a sign of intent, or a big play for Intel negotiations (these rumours always seem to crop up around the time of processor price setting negotiations...) 

    I'd love to see them do it. Intel has been on a slow trickle for years and I'd be interested to see if Apple could do better, it would set Macs apart the same way the A series sets iPhones apart, no one has been able to catch the latter. 

    Also their in-house GPU, that would be an easier start point than an ISA transition probably. 
    schlackrepressthiswatto_cobra
  • Reply 3 of 18
    macxpressmacxpress Posts: 4,963member
    A-Series Mac mini...coming soon! 

    And NO...it will NOT have replaceable RAM or storage. If this comes to fruition, I wouldn't expect this to be that much larger than the current AppleTV. Maybe slightly wide to accommodate slightly better cooling and a few USB-C ports. Doesn't really need anything else. Honestly, this would be great for kiosks, businesses and schools. They don't need tons of horsepower for general everyday stuff. 

    I believe there will always be either an Intel and/or AMD based Mac available for some time. Apple isn't quite matching those numbers for hardcore users, or even mid-core users, but in time they will get there. Apple has gotten pretty good with transitions, and make them fairly seamless. I have a feeling they're working on making something like this and will have a fairly smooth rollout similar to the PPC to Intel rollout. Sure, it wasn't perfect, but it wasn't a horrendous failure either. 
    schlackrepressthiswatto_cobraargonaut
  • Reply 4 of 18
    tipootipoo Posts: 1,058member
    macxpress said:
    A-Series Mac mini...coming soon! 

    And NO...it will NOT have replaceable RAM or storage. If this comes to fruition, I wouldn't expect this to be that much larger than the current AppleTV. Maybe slightly wide to accommodate slightly better cooling and a few USB-C ports. Doesn't really need anything else. Honestly, this would be great for kiosks, businesses and schools. They don't need tons of horsepower for general everyday stuff. 

    I believe there will always be either an Intel and/or AMD based Mac available for some time. Apple isn't quite matching those numbers for hardcore users, or even mid-core users, but in time they will get there. Apple has gotten pretty good with transitions, and make them fairly seamless. I have a feeling they're working on making something like this and will have a fairly smooth rollout similar to the PPC to Intel rollout. Sure, it wasn't perfect, but it wasn't a horrendous failure either. 

    Yeah, seeing as the Mini already has active cooling, and the passively cooled A10X was already ahead of the most current Mini, that form factor would already be interesting for an ARM Mac Mini. Add some TB3 ports and more NAND and RAM and it's already ahead. 
    repressthiswatto_cobra
  • Reply 5 of 18
    alandailalandail Posts: 690member
    I'm confused. Why does ARM-ready source code of a kernel that already run on ARM CPUs have to mean anything one way or the other about the future of MacOS?  I do think we'll eventually see an ARM based Mac, I just don't know how this relates.  Clearly ARM-ready source code for the kernel has been around for at least a decade now.

    And I'd be really shocked of Apple hasn't run internal builds of MacOS on ARM long before now. 
    edited October 2017 repressthis
  • Reply 6 of 18
    hattighattig Posts: 830member
    I agree that the Mini could be a great test bed for the concept and for encouraging future migration of applications.

    An A11X in Spring, >3GHz, 4+4 cores, 12 GPU cores, 8GB LPDDR4X... could be a nice little machine for casual Mac users. And the same chip at a lower speed could be used in the iPad Pro 2018.

    Don't tell me that the A10X in the AppleTV 4K isn't being used en-masse within Apple to repeatedly test MacOS X and certain applications for issues. Well, okay, you can suggest it's not, that's a possibility.

    This is a clue. Maybe it's just a clue for Intel to give better pricing, but maybe it's not.
    schlackwatto_cobra
  • Reply 7 of 18
    ciacia Posts: 82member
    It comes as no shock that Apple is covering it's bases by testing MacOS on ARM. I think we are still a few years out from a transition, but I can totally see this as part of their long term game plan.
    cornchip
  • Reply 8 of 18
    schlackschlack Posts: 699member
    I could see the MacBooks move to ARM processors. Apple native apps will run out of the box and 3rd party iOS apps could be adapted, allowing their core code to run as is but with refreshed UI and UX front ends. MSFT already has ARM compatible version of Office (I think). Leave the MBPs running Intel processors for hard core users with x86 needs, but put the scare in Intel to either make better processors, charge less, or both.
    watto_cobra
  • Reply 9 of 18
    schlackschlack Posts: 699member
    Apple gains a lot with an ARM chip in Macs. Better vertical integration, better development timelines, custom features, better costs, etc. But users would hopefully also get better battery life and a better performance improvement roadmap.
    watto_cobra
  • Reply 10 of 18
    fallenjtfallenjt Posts: 3,980member
    The days Apple relying on third parties for Mac CPU starts getting less and less. I bet within a few years, Mac will run on Apple designed chips and will put AMD and Intel in the shitty position: competing for WinPCs only. 
    watto_cobraargonaut
  • Reply 11 of 18
    mdriftmeyermdriftmeyer Posts: 7,300member
    Apple doesn't have a dependency on Intel anymore. It isn't due to ARM. It's due to AMD, but keep not understanding the massive differences between ARM and X86_64 instruction sets and architecture incompatibiliities, nevermind the inherent design limitations of ARM architecture and it's incapability to match anything an actual workstation or APU designed solution can produce.
  • Reply 12 of 18
    mdriftmeyermdriftmeyer Posts: 7,300member
    fallenjt said:
    The days Apple relying on third parties for Mac CPU starts getting less and less. I bet within a few years, Mac will run on Apple designed chips and will put AMD and Intel in the shitty position: competing for WinPCs only. 
    No they won't run on Apple designed CPUs. The embedded space yes, the desktop/workstation/server work, hell no.
    xzu
  • Reply 13 of 18
    fallenjt said:
    The days Apple relying on third parties for Mac CPU starts getting less and less. I bet within a few years, Mac will run on Apple designed chips and will put AMD and Intel in the shitty position: competing for WinPCs only. 
    No they won't run on Apple designed CPUs. The embedded space yes, the desktop/workstation/server work, hell no.
    Apple is not in the embedded space - they are in the Personal Computer space with custom portable and desktop systems which use ARM and x86-64 architectures.

    Apple has already shown prowess in designing custom silicon and managing the production of that custom silicon to the order of tens of millions of units a quarter [ARM].

    How many people snorted and started saying what a mistake/disaster it will be when Apple revealed that they were designing custom silicon [ARM] and said that it would less powerful, etc.

    Custom silicon allows Apple to control its destiny - not a chip manufacturer with competing interests - so it is not unreasonable for Apple to start having custom desktop processors when it fits Apple's needs and destiny.


  • Reply 14 of 18
    Apple doesn't have a dependency on Intel anymore. It isn't due to ARM. It's due to AMD, but keep not understanding the massive differences between ARM and X86_64 instruction sets and architecture incompatibiliities, nevermind the inherent design limitations of ARM architecture and it's incapability to match anything an actual workstation or APU designed solution can produce.
    Well Apple moved from PowerPC to Intel in a heart-beat when it is in Apple's best interest - so you doom-saying is overrated.

    Apple is well positioned as its various versions of OS[es] are layed - User Interface, Media/Application Services, Core Services, and Core OS/iOS kernel - which allows Apple add/modify an abstraction layer and/or kernel to work on different hardware - unlike MS Windows in which these are all combined in each version of Windows [Embedded, RT, and NT].

    mizhou
  • Reply 15 of 18
    the-other-one said: Apple is well positioned 

    ..except they let another company gain control of both the ARM architecture and a huuuuuuuuuuge amount of domestic wireless spectrum. In all fairness, the guys seem like they're being forced to work long after everyone has gone home and the sun has come up.
    williamlondon
  • Reply 16 of 18
    Apple made the switch from PowerPC to Intel due to Performance per Watt.  The PowerPC was much more power hungry than Intel with no reduction in power usage being anticipated.  The last Mac Pro model to ship with PowerPC had a liquid cooling system because it could not compete with Intel without overclocking and running hot enough to require liquid cooling.  Intel outperformed the PowerPC CPUs and used a lot less power and even far less today.  Apple was able to transition from PowerPC to Intel because Mac OS X came from NeXT whose OpenStep OS is the foundation of today's macOS Sierra and iOS devices.  OpenStep always was cross platform across several workstation class RISC CPUs such as Alpha, SPARC, etc. as well as running on Intel.  OpenStep even had a development environment on Windows called Yellow Box which was the same on all platforms and is an ancestor to Xcode.  Sir Tim Berners-Lee invented the World Wide Web on NeXT computers and John Carmack developed Doom on NeXT computers as well.  OpenStep = mac OS High Sierra which is just an evolution of what was developed at NeXT.  The operating system developed at NeXT is Apple's secret weapon. The OS was far ahead of it's time and is still relevant today.  They ported to Intel so easily because since day one, it was running on Intel in secret.  They removed the GUI and replaced it with a touch GUI for the iPad and iPhone but under the hood it's running the same UNIX kernel and many of the same API's on the iOS devices ARM CPUs.  

    Apple stripped down the ARM designs removing legacy features and optimizing for power efficiency.  The new AppleTV 4k is running an A10X ARM CPU and they don't need to worry about power efficiency because it's plugged into AC power and not a battery.  The new A11 Bionic CPU that powers the iPhone 8 and iPhone X has 6 CPU's.  Two high-speed and four efficient processors plus a custom GPU and two more CPU's tied to the machine learning engine used with FaceID.  Without the battery conservation it will give the latest MacBook Pro 13" a run for it's money.  Some benchmarks suggest it beats the MBP 13" in several areas.  That is a 10 nanometer chip design.  TRSM is working on 3-5 nanometer scale chip fabrication by 2022 in Taiwan.  The smaller the nanoscale the less power and greater the speed.  So that means ARM can eventually supplant Intel in the Performance per Watt game. (yes, Intel is at 10 nanometer and they are pursuing 7 nanometer but will it be as power efficient and will the x64 architecture be as efficient as ARM designs?).  

    So yes, Apple could certainly switch to ARM CPU's for the Mac in the future. Imagine a Mac Pro with 64 CPUs or MacBook Pro's even thinner yet faster with longer battery life requiring less cooling.  A super computer in your backpack?  Yes, it is very possible in a few short years.  

    Intel would need to make some radical new designs and who knows, maybe they can pull it off but right now, ARM is making some serious headway.  Intel is kinda stuck with their x64 architecture due to reliance on customers to buy their CPUs.  While Apple can custom design their ARM CPUs and make their operating systems run on whatever changes they make.  That is a very strong advantage.  
    uniscapeelectrosoftargonaut
  • Reply 17 of 18
    nhtnht Posts: 4,494member
    Apple made the switch from PowerPC to Intel due to Performance per Watt.  The PowerPC was much more power hungry than Intel with no reduction in power usage being anticipated.  The last Mac Pro model to ship with PowerPC had a liquid cooling system because it could not compete with Intel without overclocking and running hot enough to require liquid cooling.  Intel outperformed the PowerPC CPUs and used a lot less power and even far less today.  Apple was able to transition from PowerPC to Intel because Mac OS X came from NeXT whose OpenStep OS is the foundation of today's macOS Sierra and iOS devices.  OpenStep always was cross platform across several workstation class RISC CPUs such as Alpha, SPARC, etc. as well as running on Intel.  OpenStep even had a development environment on Windows called Yellow Box which was the same on all platforms and is an ancestor to Xcode.  Sir Tim Berners-Lee invented the World Wide Web on NeXT computers and John Carmack developed Doom on NeXT computers as well.  OpenStep = mac OS High Sierra which is just an evolution of what was developed at NeXT.  The operating system developed at NeXT is Apple's secret weapon. The OS was far ahead of it's time and is still relevant today.  They ported to Intel so easily because since day one, it was running on Intel in secret.  They removed the GUI and replaced it with a touch GUI for the iPad and iPhone but under the hood it's running the same UNIX kernel and many of the same API's on the iOS devices ARM CPUs.  

    Apple stripped down the ARM designs removing legacy features and optimizing for power efficiency.  The new AppleTV 4k is running an A10X ARM CPU and they don't need to worry about power efficiency because it's plugged into AC power and not a battery.  The new A11 Bionic CPU that powers the iPhone 8 and iPhone X has 6 CPU's.  Two high-speed and four efficient processors plus a custom GPU and two more CPU's tied to the machine learning engine used with FaceID.  Without the battery conservation it will give the latest MacBook Pro 13" a run for it's money.  Some benchmarks suggest it beats the MBP 13" in several areas.  That is a 10 nanometer chip design.  TRSM is working on 3-5 nanometer scale chip fabrication by 2022 in Taiwan.  The smaller the nanoscale the less power and greater the speed.  So that means ARM can eventually supplant Intel in the Performance per Watt game. (yes, Intel is at 10 nanometer and they are pursuing 7 nanometer but will it be as power efficient and will the x64 architecture be as efficient as ARM designs?).  

    So yes, Apple could certainly switch to ARM CPU's for the Mac in the future. Imagine a Mac Pro with 64 CPUs or MacBook Pro's even thinner yet faster with longer battery life requiring less cooling.  A super computer in your backpack?  Yes, it is very possible in a few short years.  

    Intel would need to make some radical new designs and who knows, maybe they can pull it off but right now, ARM is making some serious headway.  Intel is kinda stuck with their x64 architecture due to reliance on customers to buy their CPUs.  While Apple can custom design their ARM CPUs and make their operating systems run on whatever changes they make.  That is a very strong advantage.  
    1) There is no significant advantage between ARM and x86 as architectures.  It's all engineering trade offs of implementation and focus area.

    2) People who claim Intel has been stagnant completely ignores that they now have 4.5W parts that are as performant as 45W and 95W parts from a few years back. Intel has effectively been working on nothing BUT performance per watt for the last several generations.

    Compare the 95W i7-870 quad core in the 2010 27" iMac with Geekbench 3 scores of 2452 and 9004 to the 2017 MacBook with the 4.5W i7-7Y75 dual core with Geekbench 3 scores of 3247 and 7236.

    https://everymac.com/systems/apple/imac/specs/imac-core-i7-2.93-27-inch-aluminum-mid-2010-specs.html

    https://everymac.com/systems/apple/macbook/specs/macbook-core-i7-1.4-12-mid-2017-specs.html

    Performance per Watt vs Performance is what Intel has been working on because their top end chips were already very performant vs the competition.

    Look at their performance per Watt vs AMD.

    https://www.cpubenchmark.net/power_performance.html

    Intel has already made "radical new designs" and you already do have a "supercomputer in your backpack" with the 2017 MBP.

    3) Intel has proven it can compete with ARM in the 4.5W domain. ARM has not proven it can compete with Intel in the 100W domain. This isn't because it's not possible for ARM to do so but because they haven't spent the same engineering effort to scale up to workstation performance levels as Intel has spent to improve power performance.

    4) Where Intel loses vs ARM and AMD is performance per dollar. But so does Apple vs Dell.
  • Reply 18 of 18
    mattinozmattinoz Posts: 1,138member
    What the status of Swift Standard library in this build?

    It would seem to me if Apple want to push Swift as a server standard it would be useful to have a full supporting OS to run it in those environments as well as the Linux build options. Then they have a deployable platform any Mac developer could use to running the working parts of their code as a service that is similar to their current targets.
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