Arm v7 not arm v8? - HTC EVO 3D

It may be a typo in the build.prop but it says our processor is armv7 rev2.. Does anyone know if this is actually what's under the hood? I'd be pretty bummed

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Pretty sure the processor is based on Arm Cortex A8 so it's last generation but dual core. The SGSII is based on Arm Cortex A9. Not sure how this relates to Armv7 though.

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lokhor said:
Pretty sure the processor is based on Arm Cortex A8 so it's last generation but dual core. The SGSII is based on Arm Cortex A9. Not sure how this relates to Armv7 though.
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I was under the same impression but I'm still curious about the build.prop... idk probly just a screw up

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From here:
CPU:
Architecture: ARM v7
ARM core: ARM Cortex-A9
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Looks like there are 2 different ones. One for the chipset, one for the cores themselves. Chipset is ARM v7, Cores are A9
Also, I have no clue WTF any of this means. Google + 30 seconds = Some possibly useful info.
Edit: Okies, after doing some looking: There's no v8, only v7. The Cortex A9 is a subcategory of that, like different versions of it. Like we have gingerbread, 2.3. You can have subcategories of 2.3.3, 2.3.4, etc, which are all patches with improvements. So the CPU runs on ARM v7-A9, if that makes more sense...
Of course, this is how the processor is built, so it's not like it can be "Patched" to the newer versions when they come out... So that's just an example, to make it easier to understand.

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The Scorpion CPU is a modified Cortex A8. ALL newer Cortex Ax CPUs are based on the ARMv7 instruction set architecture (ISA.)
Summary:
CPU is based on ARM's ARMv7 instruction set architecture intellectual property, which is branded Cortex A8. (Newer TI OMAP, and the Exynos are Cortex A9, basically unmodified, but are *still* using the ARMv7 ISA.)
Ergo, ARMv7 --> instruction set architecture, Cortex A8 --> configuration/branding.

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APOLAUF said:
The Scorpion CPU is a modified Cortex A8. ALL newer Cortex Ax CPUs are based on the ARMv7 instruction set architecture (ISA.)
Summary:
CPU is based on ARM's ARMv7 instruction set architecture intellectual property, which is branded Cortex A8. (Newer TI OMAP, and the Exynos are Cortex A9, basically unmodified, but are *still* using the ARMv7 ISA.)
Ergo, ARMv7 --> instruction set architecture, Cortex A8 --> configuration/branding.
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Ah hah. Thankyou. Someone who knows what they're talking about, and isn't just pulling stuff out of their search engine.

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BlaydeX15 said:
Ah hah. Thankyou. Someone who knows what they're talking about, and isn't just pulling stuff out of their search engine.
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Glad to help. I will be starting as junior faculty at the University of Louisville, and I'm teaching microprocessor design, so I hope I can remember all this! ARM definitely has made quite a salad of their branding. For instance, the classic ARM9 CPU is based on ARMv5, while the ARM7 is based on ARMv4 (if I'm not mistaken - I have a few of the dev boards lying around somewhere... there were actually variants of the 7 and the 9 that were both under v4 and v5 ISAs). The ARM11 (which was found in the newer 400MHz+ pocket PCs and smartphones of old) used the ARMv6 architecture, and all Cortex use ARMv7. What a mess! I guess that's what happens when you just create CPU core intellectual property, without manufacturing a single chip.

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APOLAUF said:
Glad to help. I will be starting as junior faculty at the University of Louisville, and I'm teaching microprocessor design, so I hope I can remember all this! ARM definitely has made quite a salad of their branding. For instance, the classic ARM9 CPU is based on ARMv5, while the ARM7 is based on ARMv4 (if I'm not mistaken - I have a few of the dev boards lying around somewhere... there were actually variants of the 7 and the 9 that were both under v4 and v5 ISAs). The ARM11 (which was found in the newer 400MHz+ pocket PCs and smartphones of old) used the ARMv6 architecture, and all Cortex use ARMv7. What a mess! I guess that's what happens when you just create CPU core intellectual property, without manufacturing a single chip.
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I've got an iPaq sitting here...I didn't even realize it was sitting here until you said ARM11 and then I looked down in back of my keyboard, saw that and a giant whooshing sounded flew through my head and reminded me that after reading all of your posts and thinking to myself "this guy really knows his stuff...wow, I doubt I could ever know all of that stuff" that, in fact, I already did in a previous life....lol.
But as you already stated (in different words) "Knowing" is the easy part, remembering is the hard part and to that end you have one upped me.
...wow, bizarre feeling, lol, thanks...

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the scorpion core is not a modified a8 it is qualcomms own design that uses the armv7 instruction set
Sent from my PG86100 using XDA Premium App

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stimpyshaun said:
the scorpion core is not a modified a8 it is qualcomms own design that uses the armv7 instruction set
Sent from my PG86100 using XDA Premium App
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It is a modified ARM8 ISA CPU that uses the ARMv7 instruction set, Cortex is a branding.
...that is correct, and if it isn't swap a couple acronyms and numbers around and it will be.

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if you r curious here are some links talking about how the scorpion core is similar and different from both a8 and a9
http://www.qualcomm.com/documents/files/linley-report-dual-core-snapdragon.pdf
http://www.anandtech.com/show/3632/anands-google-nexus-one-review/8
http://www.anandtech.com/show/4144/...gra-2-review-the-first-dual-core-smartphone/4
http://www.anandtech.com/show/3632/anands-google-nexus-one-review/9

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stimpyshaun said:
the scorpion core is not a modified a8 it is qualcomms own design that uses the armv7 instruction set
Sent from my PG86100 using XDA Premium App
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You are correct in that the Scorpion cannot be technically branded as an A8. Qualcomm licenses the ARMv7 ISA and basic core design (which ARM called Cortex A8) (when we implement these in FPGA, we call them softcores - kinda kinky. ). Qualcomm, when designing their initial Snapdragon, essentially gave a checklist to ARM for the reference design that they wanted their IP library to use.
For instance, Intel marketed the PXA 255 and PXA 270-series CPUs. (HTC PPC 6700 and Dell Axims, anyone? ). Despite being a CPU innovator in the desktop realm, the cores were still based on ARM reference designs - Intel's mobile division selected the reference they wanted, added MMX, etc., and then went to fab with it. By the same token, the Scorpion was based on ARMv7 ISA, which in its initial incarnation, as used by Qualcomm, was the Cortex A8. What came out of that is, logically, different, but related enough, the same way the PXAs were ARM11 reference desgins (ARMv6.) Qualcomm added the NEON instruction set, as well as out-of-order execution, for example, something the other Cortex CPUs didn't have (this may have changed with the A9), in order to increase data and instruction-level parallelism. They also added the ability to perform fine-grain CPU clock frequency and voltage throttling, much more so than in the stock A8 reference.
I guess in the long run, if they don't update their references to an A9 IP library variant, or perhaps something newer down the road, the Scorpion will start lagging behind the competition rather significantly. Not that I'm complaining at the moment, I love my 3vo's performance as it is.

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http://www.qualcomm.com/documents/files/linley-report-dual-core-snapdragon.pdf
here it says qualcomm does not use arms cortex reference designs but infact designed its own
if it is wrong than blame qualcomm... if I am misunderstanding it please explain

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stimpyshaun said:
http://www.qualcomm.com/documents/files/linley-report-dual-core-snapdragon.pdf
here it says qualcomm does not use arms cortex reference designs but infact designed its own
if it is wrong than blame qualcomm... if I am misunderstanding it please explain
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Boy, they certainly make it sound that way! My guess is that the truth lies somewhere in the middle. That they don't use the reference design is clear - the end-product isn't the same product that is the core design in the Cortex/v7 spec. However, I don't think that Qualcomm has the capital and the resources to do a full-scale, ground-up build of a CPU. Note that even Intel didn't do this (!) when they entered (and then promptly exited) the mobile CPU-building business.
The Qualcomm processor design team most-likely chooses attributes and then custom-designs additional features and configurations, and Qc does have the fabs to produce the silicon to state-of-the-art, or (state-of-the-art - 1) process technologies, as is clear from their stated transistor design (with a certain leakage factor) and feature size (45nm - keeping in mind that Samsung has this down to 32nm (you might want to check me on that, this may be a lie )).
So, let me restate my original opinion - I value your inputs, and this document certainly does its best to make the CPU look unique in the market. My understanding is that a certain core of the IP library is still present in the A8 format from ARM. It's entirely possible that none of the original architecture was kept in its native forms - design, routing, and layout might all be different, but I think ultimately, the CPU finds its roots in part of the original A8 design. To simply use the ISA without *any* reference to the original A8, I think, is beyond Qualcomm's capabilities, at least at present.
I suppose a reasonable example may be seen in the car world. Take the Lexus ES series vs. the Toyota Camry (just to name a plain-jane, basic example that most people would know.) The ES looks, performs, and runs differently. It has different features, a different pricetag, and many different interior and even engine-bay features (and probably a larger engine.) But ultimately, it is just an altered Camry. The extent of the alterations here is the question (and bringing an analog to an ISA into the automotive domain is tricky - maybe the use of an engine and 4 wheels? ). Anyway, perhaps only Qualcomm knows the answer, but well done sir, in bringing an in-depth discussion to the table.

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To put this into layman's terms:
You can mostly think of the term "architecture" as being a language that the CPU speaks, and the software must therefore be written in that language (or as programmers refer to it, being compiled into that language.) Android apps speak java bytecode to the dalvik engine, which then translates and speaks ARMv7 to the CPU. Different phones can run on different architectures and still have the apps be compatible because the dalvik engine can be compiled for each different architecture.
Now, the "core" in this sense is the specific implementation of that architecture. The easiest analogy to that I can think of, is that intel and AMD CPU's both use the x86 architecture, but their implementations are way different. They are designed far different from one another, but in the end they speak the same language more or less.
There are variations to the ARM "language" which is indicated by the revision number (ARMv7) just as there are variations to the x86 "language." For example, you have x86 32-bit and you have x86 64-bit, and then there are extensions to x86 such as SSE, 3dnow, etc. It's a little more complicated than that, but that's the general idea.