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ARM SoC launched with Linux support (Linux Devices)

ARM SoC launched with Linux support (Linux Devices)

Posted Jan 9, 2009 10:48 UTC (Fri) by ajb (subscriber, #9694)
In reply to: ARM SoC launched with Linux support (Linux Devices) by gnb
Parent article: ARM SoC launched with Linux support (Linux Devices)

Because the Xscale license held (now) by Marvell is more permissive than the standard ARM licenses - they can make derived works.


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ARM SoC launched with Linux support (Linux Devices)

Posted Jan 9, 2009 11:33 UTC (Fri) by gnb (subscriber, #5132) [Link]

Yes, I realise that, I probably worded the question badly. What isn't clear
to me is that they get any technological advantage out of it any more. Time
was when strongarm, and subsequently the xscale, were clearly faster than the
cores ARM were selling, but is that still true (my impression is that it
isn't) and if not why keep putting R&D into an in-house implementation of an
antiquated version of the ARM ISA?

ARM SoC launched with Linux support (Linux Devices)

Posted Jan 9, 2009 13:37 UTC (Fri) by nhippi (subscriber, #34640) [Link]

Marvell mv78200 (a armv5t) is still very much the fastest ARM around (perhaps Qualcomm snapdragon beats it, but I'm not sure how available it is yet).

Also, if you read the fine article, they link to a (very insightful) Marvell .pdf which mentions that the next generation (to be announced 2009) is "fully armv6 and armv7 compatible".

ARM SoC launched with Linux support (Linux Devices)

Posted Jan 9, 2009 14:45 UTC (Fri) by robert_s (subscriber, #42402) [Link]

"Marvell mv78200 (a armv5t) is still very much the fastest ARM around"

Faster than any of the OMAP3s?

ARM SoC launched with Linux support (Linux Devices)

Posted Jan 9, 2009 23:08 UTC (Fri) by endecotp (guest, #36428) [Link]

My recollection is the the mv78200 has two cores, each capable of issuing two instructions per cycle, running at a little over 1GHz. Can anyone quote comparable data for the OMAP?

ARM SoC launched with Linux support (Linux Devices)

Posted Jan 10, 2009 1:02 UTC (Sat) by drag (subscriber, #31333) [Link]

Well it's probably more comparing apples to oranges.

With the proprietary drivers for the PowerVR SGX video stuff (also used in Intel's Atom stuff when not using the desktop oriented 945g stuff) then Ti's OMAP3 platform can decode and playback 720p video over DVI interface in realtime. It can do GLSL and has effective 3D graphics. (it's used in the Pandora handheld gaming system which can play Quake 2 with steady 40fps.)

And also besides the PowerVR stuff the Cortex-A8 core (the OMAP3 is TI's baby, while the Cortex-A8 is at least licensed by Freescale also and freescale has it's own platform in the works. For example OMAP3x stuff so far only supports DDR1, while Freescale supports DDR2) supports full ARMv7, NEON instruction set and SIMD stuff.

The Cortex-A8 can do 1ghz, has 13 stage integer pipeline, 10 stage NEON, L2 cache ranging from 64K to 2M, runs using 300mA worth of power, and has some crypto acceleration besides other features. Blah blah.

You can find nice PDF's describing all of this with easy google'ng

In the future Cortex-A9 cores should be coming out and they are the multicore versions of the same architecture. I think they are designed, but I haven't seen anybody using them yet.

Both of these can be clocked at excess of 1ghz given proper fabrication and power requirements.

---------------------

However the MV stuff your talking about is optimized for network performance with the ability to do 4 ethernet ports and happy fun stuff like that. It's dual core is probably more optimized for traditional ARM integer functions and thus is probably much better at some tasks then the OMAP3 is.

---------------------

It would be interesting to see benchmarks to compare various ARM systems and help people decide with architecture is good for them.

The nicest thing about Ti is that they are very developer friendly. They provided the Beagleboard, which is a developer's board that is insanely cheap for the performance it offers. $150

http://beagleboard.org/hardware

For another 350 dollars you can get a nice mini projector from Ti to go with it. A entire Linux PC with with HVGA graphics on a 30 inch display you can fit in one pocket for around 600 bucks.

Then the Pandora handheld gaming thing is using it. I don't think they are selling yet, but they have released pre-production devices to testers/developers.

Also Gumstix is producing the OMAP3-based Overo for hackers for $150 for their flexible and tiny gumstix formfactor.

So all of this platform is very accessible to Linux hackers and hobbyists. If it wasn't for the proprietary 3D drivers then it would be almost perfect for low-power systems.

OMAP3...

Posted Jan 10, 2009 13:13 UTC (Sat) by HalfMoon (guest, #3211) [Link]

OMAP is probably best known for being energy-efficient, which XScale never did that well. The process technologies have really affected the hardware designs, which gets to be really significant with smaller geometries where leakage currents *really* hurt. OMAP has quite a few power domains on the chip, which can be individually switched off; and that's on top of selecting power-efficient transistors. That's critical if you're going to eke out a week's usage off teeny tiny batteries... and part of why it's not clocked as fast as the ARM core would allow.

Also, OMAP3 has four basic options. OMAP 3503 (the one in the entry level Gumstix Overo) has no video accelerators. The higher end chips can give you one or both of: the OpenGL engine; or a rather powerful C64x+ fixed point DSP (VLIW, four concurrent ALUs, many MMACs/sec). The Beagle board has one of the higher end chips (OMAP 3530), with all the available graphical goodies. (But not the "secure" version used in most cell phones.) If you need number crunching, use the DSP not the ARM.

You can compare the OMAP 3525 (ARM plus DSP, no OpenGL hardware) to the DaVinci 6446, which is marketed as a video processor; except the OMAP has more peripherals, a much faster ARM (Cortex-A8 vs arm926), and better power management.

OMAP3...

Posted Jan 13, 2009 2:28 UTC (Tue) by drag (subscriber, #31333) [Link]

Thanks for the info. It is very valuable.

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