Microblaze and PowerPC

[am85]

Hi,
I would like to perform mathematical operations as Division and Squar
root. From what i have read, i either need to use Microblaze or PowerPC
can anyone please tell me the difference in performance between them, an
is it a hardware or software calculation. Does each one of these option
has a dedicated FPU?



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Posted through http://www.FPGARelated.com

 

[Rob Gaddi]

On 6/2/2011 7:50 AM, am85 wrote:

Hi,
I would like to perform mathematical operations as Division and Square
root. From what i have read, i either need to use Microblaze or PowerPC.
can anyone please tell me the difference in performance between them, and
is it a hardware or software calculation. Does each one of these options
has a dedicated FPU?



---------------------------------------
Posted through http://www.FPGARelated.com

Not at all true. Either of those algorithms can be implemented, either
in fixed or floating point, as pure hardware.

--
Rob Gaddi, Highland Technology
Email address is currently out of order

 

[glen herrmannsfeldt]

Rob Gaddi <rgaddi@technologyhighland.com> wrote:

On 6/2/2011 7:50 AM, am85 wrote:

I would like to perform mathematical operations as Division and Square
root. From what i have read, i either need to use Microblaze or PowerPC.
can anyone please tell me the difference in performance between them, and
is it a hardware or software calculation. Does each one of these options
has a dedicated FPU?

Not at all true. Either of those algorithms can be implemented, either
in fixed or floating point, as pure hardware.

And either pipelined or combinatorial.

-- glen

 

[Martin Thompson]

"am85" <ammarei@n_o_s_p_a_m.hotmail.com> writes:

Hi,
I would like to perform mathematical operations as Division and Square
root. From what i have read, i either need to use Microblaze or PowerPC.

Where did you read that? You can perform those mathematical operations using
the FPGA fabric perfectly well.

can anyone please tell me the difference in performance between them, and
is it a hardware or software calculation. Does each one of these options
has a dedicated FPU?

To directly answer the question, Microblaze has an optional FPU (made of LUTs
and flipflops). IIRC PowerPC could have an FPU added (also made of LUTs and
FFs) so I'd expect performance on those operations to be similar(ish).

Microblaze with an FPU in a Spartan3ADSP will clock happily at tens of MHz.
Maths performance is limited - the square-root takes ~30 cycles to
complete, so you may get 2-3 Msqrts/sec.

Conversely I've written a pretty wide fixed-point square-root which runs at
about the same clock rate, but produces an answer every clock cycle (heavily
pipelined).

Cheers,
Martin

--
martin.j.thompson@trw.com
TRW Conekt - Consultancy in Engineering, Knowledge and Technology
http://www.conekt.co.uk/capabilities/39-electronic-hardware