Down-clocking

[Loonie]

I know the CPU clock can be moved up or down, but I'm curious to know if the memory/GPU/NEON clock speeds can be changed. Not actually for overclocking, but rather to produce speeds similar to the 3530 SOC. Whatever I may develop, I want to ensure it runs decently on the standard hardware.

 

[mcobit]

To get a really good comparison you would not only need to downclock the cpu but also the ram, dsp and sgx, what I don't think is possible. But the cpuclock should be adjustable as with the old Pandoras.

 

[Exophase]

There's no NEON clock speed, NEON is part of the CPU. It's like SSE on x86 processors.


You may be able to change the memory, but this wouldn't really get you exactly equivalent to the OMAP3530. You still have twice the L1 cache and the memory subsystem appears to be more efficient beyond just having a higher clock speed. But right now the difference of everything is still usually just a few (< 10) percent at the same clock. So I wouldn't stress the memory clock difference unless performance is really marginal.


SGX clock difference could be more substantial if you're actually doing 3D that isn't CPU bound; first you should ascertain that. I'm not sure what's offered on DM3730 or how to change it.. on OMAP3530 you were limited to just a few clock setups and here 110MHz might not be an option..

 

[notaz]

Current firmware supports changing RAM/system clock already, so you can set it to 3530 levels on 3730. SGX 3530 dividers are also still there, but there is no way to change them without recompiling the driver at the moment.

 

[Loonie]

CPU and RAM will probably be enough. I doubt I'll be doing any fancy 3D or NEON stuff. I understand achieving identical performance to the 3530 will basically be impossible, but it should be feasible to get a rough idea at least. Thanks for the info.