
ARM’s Mali Midgard Architecture Explored - srikar
http://www.anandtech.com/show/8234/arms-mali-midgard-architecture-explored
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hupholand
Could somebody familiar with the tech explain the Midgard execution model
described on page 6 of the article. I don't understand how each arithmetic
pipeline of the Midgard is "essentially it's own cpu". If this is the case,
it's perfect no as I get an vast array of independent SIMD units. What is the
downside?

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lxgr
I could imagine that independent SIMD units require more additional resources
like instruction decoders and branch units, whereas in the warp/wavefront
model, many ALUs can share those units, saving die space and energy. If the
executed workloads are mostly coherent, that resources are wasted.

It's interesting that ARM switched to independent ALUs/SIMDs, because if I
understand it correctly, that is exactly what PowerVR was doing with its SGX
architecture before switching to a wavefront-like execution model. In a way,
they are going in the opposite direction.

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lxgr
First PowerVR, now Mali – great news! I wonder if Qualcomm will ever publish
some specs on Adreno, though.

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rjsw
Read the comments below the article.

