Enter the Snapdragon

These days pretty much any new smartphone that launches seems to have a Qualcomm Snapdragon SoC in it. While I've covered ARM's Cortex A8 before, I've never really talked about the Qualcomm Snapdragon before. Let's change that.

ARM is a different sort of microprocessor company than the ones we're used to covering. AMD and Intel design the instruction set, microarchitecture and ultimately do everything up to (and including for Intel) actually fabbing the chip. Owning the entire pipeline from ISA (instruction set architecture) all the way down to manufacturing is expensive. The graph below shows the rough costs of simply keeping up with fab technology every two years:

That's not really feasible for most companies. In fact, AMD recently got out of the fab business partly because of the incredible costs associated with it. Actually designing these architectures is a tough job. It'll take a large team of highly talented engineers multiple years to crank out a good design. Then you've got to test the chip and ultimately, you have to sell it.

Now it's hard to sell just a microprocessor, which is why both AMD and Intel offer a full platform solution. You can buy graphics, chipsets, SATA controllers, basically everything but a motherboard from these companies. It's difficult for a company to offer such a complete solution.

To sell the chips you need customers, you need to be able to deliver on their schedules and keep the whole machine running. Fabs, engineering, testing/validation, sales and marketing - it's an expensive business to run.

There's rarely room in any mature market for more than two competitors. And among those two competitors, there's never room for both to behave the same way. This is why AMD and Intel have wildly differing approaches to microprocessor architectures at the same process technology node. ARM can't follow in Intel's footsteps, so the alternative is to cut away the excess and remain focused.

Which is exactly what ARM does. ARM will sell you one of two things: a processor architecture, or a license to use its instruction set. The majority of customers take the former. If you're a processor licensee this is how it works.

At the core ARM creates an instruction set, just like Intel and AMD use x86, ARM has its own ISA. Next, ARM will actually create an entire processor designed around this instruction set. For example, the Cortex A8 is an ARM design based upon the ARMv7 ISA - just like the Core i7 is based upon Intel's x86 ISA.

This processor is tested, validated but not manufactured by ARM. Instead, ARM will give a licensee everything it needs to integrate this CPU core into its own design. Remember the part about needing a platform? It's usually up to the customer to grab a GPU, video decoder, image processor, etc... and put them all on a single chip with the ARM core they've just licensed. This way ARM doesn't have to deal with the complexities of lining up five different roadmaps and delivering a chip that its customers want. ARM provides the CPU, Imagination or some other company will provide the GPU IP and so on and so forth. Everyone gets a chip tailored to their needs.

Like I said, the majority of companies take this route. It's more cost effective because you don't have to do the CPU design yourself. You do lose a bit of a competitive edge, as your competitors can easily license the same cores you do. So you can differentiate based on how well you integrate all of this IP, what tradeoffs you make vis-a-vis power vs. performance vs cost, or marketing prowess, but not on base architecture. Take this route and you do run the risk of your chips performing the same as your competitors. Companies like TI (OMAP3, OMAP4) and Samsung (S5PC100) are ARM processor licensees. They license ARM11, ARM Cortex A8 and ARM Cortex A9 cores and integrate them into SoCs along with a GPU, video decoder and other IP that they source from various companies.


Samsung's S5PC100 is based on the Cortex A8 licensed from ARM

With as many players as there are in the SoC market, differentiation is key. For customers looking for more gain at the expense of increased risk, ARM offers a second option: an architecture license.

An architecture license means that you have the right to use the underlying ISA. AMD and Intel have broad cross licensing agreements in place that allow them both to produce x86 processors using instructions introduced by each maker. I don't have a license to the x86 ISA so you and I can't go out and sell our own x86 CPU tomorrow. Sorry.

Companies like Marvell are architecture licensees. They take an ARM instruction set (e.g. ARMv6, ARMv7) and use their own engineers to build a microprocessor around it.

This is a much more costly and risky approach. Building a CPU isn't easy, in fact the faster it is, the more complex and difficult the task becomes. Even companies that have tons of experience doing it screw up from time to time. It takes a lot of time, requires smart folks and you have to pay them good salaries. The upside is that with a bit of effort, you can outperform ARM's own designs. As with most things in life, the larger the risk, the larger the upside.

This is the route Qualcomm took.

Notifications: Better than Apple, Worse than Palm Inside Snapdragon is a Scorpion
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  • KaarlisK - Saturday, April 03, 2010 - link

    ´´The graph below shows the rough costs of simply keeping up with fab technology every two years:´´
    Can´t seem to find it.
    Reply
  • deputc26 - Saturday, April 03, 2010 - link

    Thanks Anand, Great Review! Reply
  • windywoo - Sunday, April 04, 2010 - link

    Taken out of context like that, the quote sounds like it is describing a graph of smartphone prices, laptops, e-readers :) Fab tech. Reply
  • Nihility - Saturday, April 03, 2010 - link

    I just know that after experiencing any responsiveness issues, that within a few months I'll get really frustrated with the device.
    I still have an iPhone 2G and I hate it. Takes forever to launch apps, browsing the web is a miserable experience and the battery life sucks. I'm definitely in the market for a better phone but I think I'll just wait for something smoother.

    One of my main gripes is that my navigation app for the iPhone takes ages to load and if I get a call mid-work I'll have to restart it. Hate that.

    Like Anand said, on paper the N1 is perferct but I'll let them smooth out the rough parts before I get one.
    Reply
  • Exelius - Saturday, April 03, 2010 - link

    I had the same complaint of my iPhone 3G. I bought a 3GS the day it came out and it is a huge improvement over both the 2G and 3G in responsiveness. My girlfriend has a regular 3G and much prefers using my 3GS over her own phone when browsing the web or using the Maps application.

    If responsiveness is a problem on the iPhone platform, get a 3GS before ditching the iPhone completely. The hardware on the 3GS is roughly equivalent to the Nexus One.
    Reply
  • Nihility - Saturday, April 03, 2010 - link

    No way. Fool me once, shame on you. Fool me twice...
    No more iPhones for me.

    My main concern was all my apps, but most of them are available for the Android so there's nothing holding me back. I'll be glad to get rid of iTunes.
    Reply
  • solipsism - Saturday, April 03, 2010 - link

    You're comparing a phone from 2007 with an ARMv6 @400MHz w/ 128MB RAM and discounting the model that came two years later with ARMv7 @ 600MHz w/ 256MB RAM. Makes perfect sense¡ Reply
  • KaarlisK - Saturday, April 03, 2010 - link

    I love both the attention to detail and depth you have :)

    And I have to say that Android, not WinMo7, is the replacement for Windows Mobile 6.5 in my eyes. WinMo7 just isn´t WinMo :D
    Reply
  • LuxZg - Sunday, April 04, 2010 - link

    I agree, great review, I think I've never read anything that long about a phone :)
    And I agree with Android being a true Windows Mobile successor.. I don't have money for stuff like this, but if I did - I'd want all the freedom of my PC on my mobile as well. In that regard, Android seems to be the only option at the moment.

    There is one thing that will clearly make lives of some people miserable.. Data rates in some countries are horrible, and smartphones all rely on mobile data connection heavily, but Nexus One is a data-hog champion by the looks of it. Hopefully, by the time I'll be able to afford phones like this one, this will be solved :)
    Reply
  • macs - Saturday, April 03, 2010 - link

    Thank you Anand, the review is great and as an owner of the Nexus One I agree with your thoughts.

    Android world is so wide that it's really hard to have a complete review and I think what is really missing here is something about the community around Android, XDA forum, CyanogenMOD , USB Tethering, WIFI Tethering,...
    Reply

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