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MacRumors
Sep 23, 2011, 10:25 AM
http://images.macrumors.com/im/macrumorsthreadlogo.gif (http://www.macrumors.com/2011/09/23/support-for-marvell-quad-core-arm-chips-found-in-xcode/)


http://images.macrumors.com/article-new/2011/09/marvell_armada_xp.jpg


Ars Technica reports (http://arstechnica.com/apple/news/2011/09/support-for-quad-core-arm-cpu-shows-up-in-apples-xcode-but-why.ars) that support for Marvell's quad-core Armada XP processor has recently been added to the version of Apple's "Clang" compiler used in its Xcode developer tools. It is unclear, however, why support for the ARM-based processor has been included.A developer who works on low-level ARM assembly coding for security products was the first to alert Ars that support had been added for Armada's Cortex A9-compatible processors in the latest version of Xcode (a claim that we later confirmed first-hand). The source code for a part of Clang that interprets what CPU type is being targeted for optimization includes a definition for an architecture type of "armv7k" and CPU type "pj4b". PJ4B is a specially optimized CPU design used in Marvell's quad-core Armada XP embedded processors.The reports suggests that while the inclusion of Armada XP support could point toward potential adoption of the processor in a future iOS device or even a MacBook Air, it is more likely that Apple is using the processor in prototypes simply for testing purposes as it continues work on its own ARM-based chips.

Several reports (http://www.macrumors.com/2011/08/03/apple-to-begin-merging-ios-and-os-x-with-quad-core-a6-chip-next-year/) have indicated (http://www.macrumors.com/2011/08/26/no-a6-chip-for-ipad-until-june-2012-at-the-earliest/) that Apple's next-generation A6 system-on-a-chip will offer a quad-core processor, although Ars Technica's report suggests that the A6 is primarily being designed as die shrink of the existing dual-core A5 design.

Article Link: Support for Marvell Quad-Core ARM Chips Found in Xcode (http://www.macrumors.com/2011/09/23/support-for-marvell-quad-core-arm-chips-found-in-xcode/)



chrmjenkins
Sep 23, 2011, 10:36 AM
I wouldn't guess anything but prototyping. Their internal team has proven themselves more than capable with the A4 and A5.

I also agree with Ars' prediction that A6 will simply be a 28nm die shrink of the A5. Have to save all the power they can to squeeze in a new LTE chip from Qualcomm.

alent1234
Sep 23, 2011, 10:53 AM
A4 and A5 are just modified Samsung ARM CPU's. maybe for A6 Apple is going with another reference design?

jayducharme
Sep 23, 2011, 11:03 AM
I still find it hard to believe that we're talking about a quad-core processor inside a phone! Just a few years ago, I was stunned that one was possible inside a desktop computer.

Henriok
Sep 23, 2011, 11:06 AM
Clang is an open source project, that Apple is heavily invested in. But It could be that the support is included by someone else. Since it is an open source project, one could probably dig into the project and find out who included the support.

The Armada cores are ARMv7 compliant but they are not derived directly from ARM's own core design (Coretex A8 and A9) as are the A4 and A5. I have no clear idea of what this means for iOS development though.
I think it's unlikely that Apple will use Armada XP processors in any product since they are not designed for cellphones of portable devices. It's plausible though that Apple is using them for simulating stuff for future designs.

cube
Sep 23, 2011, 11:06 AM
I still find it hard to believe that we're talking about a quad-core processor inside a phone! Just a few years ago, I was stunned that one was possible inside a desktop computer.

Low-power cores are much simpler than desktop cores.

commander.data
Sep 23, 2011, 11:25 AM
http://www.appleinsider.com/articles/08/03/06/teardown_a_look_inside_apples_time_capsule_backup_appliance.html&page=2

Apple currently uses Marvell SoC in the Time Capsule and Airport Extreme. Perhaps Apple wants to expand the Time Capsule to become a mini-server and needs a quad core, but wants to stick with Marvell? This would certainly fit with those rumours before of the Time Capsule gaining the ability to store and stream both media and OS updates to connected devices.

guzhogi
Sep 23, 2011, 11:33 AM
But will it play Crysis?

chrmjenkins
Sep 23, 2011, 11:36 AM
A4 and A5 are just modified Samsung ARM CPU's. maybe for A6 Apple is going with another reference design?

A4, yes (the hummingbird core in 1st gen Galaxy S devices), but the A5 is a heavily modified Cortex A9 architecture. It doesn't resemble anything in Samsung's portfolio other than the fact that their Exynos chip is also a dual core Cortex A9 design (which it also shares with the Tegra 2 and OMAP 4). They have different GPUs and different die shapes (although their sizes are very similar).

http://www.anandtech.com/show/4686/samsung-galaxy-s-2-international-review-the-best-redefined/14
http://www.itproportal.com/2011/06/13/exclusive-apple-a5-vs-samsung-exynos-4210-soc-die-shot-comparison/

alent1234
Sep 23, 2011, 11:36 AM
I still find it hard to believe that we're talking about a quad-core processor inside a phone! Just a few years ago, I was stunned that one was possible inside a desktop computer.

it's just multiple execution units that share a cache. it's not like real multiple CPU's on a single die

Henriok
Sep 23, 2011, 11:39 AM
Apple currently uses Marvell SoC in the Time Capsule and Airport Extreme. Perhaps Apple wants to expand the Time Capsule to become a mini-server…
I don't think have anything to do with anything. If they went down this route with AitPort stations, they probably would re-use their Ax design or use an Atom based chip from Intel.

chrmjenkins
Sep 23, 2011, 11:42 AM
it's just multiple execution units that share a cache. it's not like real multiple CPU's on a single die

Mobile quad cores follow the same philosophy as desktop ones. I don't see a distinction. They both share caches too.

longofest
Sep 23, 2011, 11:49 AM
But will it play Crysis?

obligatory "no". not all quad-cores are created equal.

----------

A4, yes (the hummingbird core in 1st gen Galaxy S devices), but the A5 is a heavily modified Cortex A9 architecture. It doesn't resemble anything in Samsung's portfolio other than the fact that their Exynos chip is also a dual core Cortex A9 design (which it also shares with the Tegra 2 and OMAP 4). They have different GPUs and different die shapes (although their sizes are very similar).

http://www.anandtech.com/show/4686/samsung-galaxy-s-2-international-review-the-best-redefined/14
http://www.itproportal.com/2011/06/13/exclusive-apple-a5-vs-samsung-exynos-4210-soc-die-shot-comparison/

Ah... OMAP :) Just recently was looking pretty heavily at OMAP designs because they are some of the few that have TI's C64x DSPs, but it looks like OMAP 4 is starting to migrate away from that...

commander.data
Sep 23, 2011, 11:58 AM
I don't think have anything to do with anything. If they went down this route with AitPort stations, they probably would re-use their Ax design or use an Atom based chip from Intel.
Going with an Apple Ax processor or Atom would be useful if Apple intended to run a variant of iOS or OS X on the Time Capsule, but since they don't need all the high level APIs. They'd more likely stick with evolving their current firmware/low-level OS implementation.

The other argument for Apple Ax in particular, is that it's potentially cheaper to reuse existing technology. However, Apple's justification for the designing their own processors is that it enables them to strip out all the functions they don't need, particularly extraneous I/O, that wastes power. Assuming Apple has done that in order to optimize the SoC for handheld use, it is no longer appropriate for the Time Capsule. The Quad Core Marvell Armada XP on the other hand has integrated Gigabit ethernet controllers to support up to 4 ports and multiple PCIe lanes to attach extra I/O like the WiFi controller. Seeing the Apple A5 has little need for 4 Gigabit ethernet ports, Apple will continue to have to use third-party SoC for the Time Capsule and Airport Extreme.

Mad-B-One
Sep 23, 2011, 12:01 PM
It might very well be a testing lab thing. If someone wants to optimize addressing 4 cores just to see if the load spread is working properly, it is the right way to use an existing chip which is a close as it can get to the ones used right now. That does not mean it will be used in iDevices. When I use my 6 core processor, I see that even brand new software is not optimized for multicore systems beyond 2 cores. Early implementation in software design would help to save battery life down the line if programmers can test quadcores early on.

guzhogi
Sep 23, 2011, 12:03 PM
obligatory "no". not all quad-cores are created equal.

Looks like someone needs to realize what sarcasm is…

*LTD*
Sep 23, 2011, 12:12 PM
But will it play Crysis?

Crysis?

Pffft . . .

Infinity Blade is the new benchmark. :p

Skika
Sep 23, 2011, 12:12 PM
Oh boi do i want a fanless MBA with an ever better battery life for occasional browsing and writing.

*LTD*
Sep 23, 2011, 12:14 PM
Oh boi do i want a fanless MBA with an ever better battery life for occasional browsing and writing.

You can already get one:

http://www.apple.com/ipad/

commander.data
Sep 23, 2011, 12:18 PM
It might very well be a testing lab thing. If someone wants to optimize addressing 4 cores just to see if the load spread is working properly, it is the right way to use an existing chip which is a close as it can get to the ones used right now. That does not mean it will be used in iDevices. When I use my 6 core processor, I see that even brand new software is not optimized for multicore systems beyond 2 cores. Early implementation in software design would help to save battery life down the line if programmers can test quadcores early on.
Does ARM themselves offer any dev boards? They can't just be designing the architecture theoretically and waiting for someone to implement it to see how it works. And I can't see SoC makers licensing a new architecture unless ARM can show them working reference boards to prove the benefits over the previous architecture.

And as pointed out by others, if Marvell uses a custom ARMv7 architecture it's not the best reference point to do your optimization compared to using sa y nVidia Tegra 3, TI OMAP5 or Freescale i.MX6 which appear to use stock Cortex A9.

wizard
Sep 23, 2011, 01:17 PM
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Clang is an open source project, that Apple is heavily invested in. But It could be that the support is included by someone else. Since it is an open source project, one could probably dig into the project and find out who included the support.

The Armada cores are ARMv7 compliant but they are not derived directly from ARM's own core design (Coretex A8 and A9) as are the A4 and A5. I have no clear idea of what this means for iOS development though.
I think it's unlikely that Apple will use Armada XP processors in any product since they are not designed for cellphones of portable devices. It's plausible though that Apple is using them for simulating stuff for future designs.

Give this guy a cookie. Finding support for other processors in CLang means nothing as it is open source. You need more information than just saying it is included, for example who included it, is it a standard item when clang is built for ARM & etc.

As to quad cores I suspect they are coming and may arrive in IPad 3. The next chip we see from Apple is likely a low power A5 that has been enhanced somewhat. It is likely one of the hold ups for the new iPhone as A5 is currently a little hot for that.

commander.data
Sep 23, 2011, 01:47 PM
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Give this guy a cookie. Finding support for other processors in CLang means nothing as it is open source. You need more information than just saying it is included, for example who included it, is it a standard item when clang is built for ARM & etc.
As explained in the Ars Technica article, the Marvell support was added in Apple's private branch of CLang. If the open source flag is defined, then the Marvell support is disabled.

http://arstechnica.com/apple/news/2011/09/support-for-quad-core-arm-cpu-shows-up-in-apples-xcode-but-why.ars
The source code, available from Apple's open source repository, also shows that support for the processor is only added when an "open source" flag (__OPEN_SOURCE__) is undefined. This suggests that only Apple's internally built Clang binaries can target code compilation for the Armada XP.

MacinDoc
Sep 23, 2011, 01:54 PM
Perhaps for the next-generation Apple TV?

z3r0
Sep 23, 2011, 03:41 PM
Well Apple is already starting to source flash storage away from Samsung (http://www.macrumors.com/2011/09/21/apple-diversifying-memory-suppliers-too-moving-away-from-samsung/). It would be reasonable to conclude that they would want to move away from Samsung ARM CPU parts as well.

As a precautionary move due to Samsung's ongoing litigation (http://www.macrumors.com/2011/09/23/samsung-stepping-up-attacks-on-free-riding-apple-in-patent-dispute/)

It might also have to do with VIA. Perhaps Marvell CPUs don't violate VIA patents (not saying that Apple does right now, but its just in case!) http://www.macrumors.com/2011/09/22/via-technologies-files-patent-lawsuit-against-apple-over-ios-device-processors/

theBB
Sep 23, 2011, 04:18 PM
Well Apple is already starting to source flash storage away from Samsung (http://www.macrumors.com/2011/09/21/apple-diversifying-memory-suppliers-too-moving-away-from-samsung/). It would be reasonable to conclude that they would want to move away from Samsung ARM CPU parts as well.
They don't use Samsung CPUs, but I wouldn't know if they are buying some IP or know-how from Samsung.

mdriftmeyer
Sep 23, 2011, 04:33 PM
ARM is adding it's CPU architecture list to LLVM/Clang on a daily basis. For Xcode to see it is natural--the update to Xcode will have LLVM/Clang 3.0 with all the ARM additions.

accessoriesguy
Sep 23, 2011, 06:01 PM
code for an A9 that would be acceptable enough for the macbook air. If they were able to make a smaller thunderbolt chip (hopefully to come). and apple does their magical engineering procedures, a macbook air with a much more powerful ARM chip (not just the one iOS devices use) and a good GPU pair (or just let the ARM chip have the built in GPU) that would be a very powerful computer that I wouldn't mind ditching intel for.

Than again, Ivy Bridge or Trinity, would make very beautiful additions to the product line as well.

tobian
Sep 25, 2011, 08:23 AM
I still find it hard to believe that we're talking about a quad-core processor inside a phone! Just a few years ago, I was stunned that one was possible inside a desktop computer.

My first iPod had a dual-core processor and FireWire 400 bus.. that's almost ten years ago.

kiljoy616
Sep 25, 2011, 05:52 PM
Not sure about the iPhone but a quad-core ipad 3 sure why not, blow everyone out of the water and humiliate them in the same sentence. ;)

PinkyMacGodess
Sep 25, 2011, 06:39 PM
Not sure about the iPhone but a quad-core ipad 3 sure why not, blow everyone out of the water and humiliate them in the same sentence. ;)

I think it's too early for a quad core iPad. Apple doesn't need one yet to fend off competition. I'd think in the iPad 4 or 5. It could happen in the 3 but I'd imagine that the number of iPad 1's and 2's that could/would flood the market wouldn't be good for sales of the iPad 3 quad core...

Rodimus Prime
Sep 25, 2011, 06:48 PM
I really do not read much into this as quad core power tablets are expected in 1st Quarter 2012 and quad core phones are expected to be out in 2012 to me it is kind of a "well duh" thing.

emmahudson88
Sep 26, 2011, 10:22 PM
I wouldn't guess anything but prototyping. Their internal team has proven themselves more than capable with the A4 and A5.

I also agree with Ars' prediction that A6 will simply be a 28nm die shrink of the A5. Have to save all the power they can to squeeze in a new LTE chip from Qualcomm.

I agree with you