Hello
I am using a Virtex2Pro board and lately I was trying to use the PowerPC at the highest speed (300MHz) on my board. I have a function which uses a lot of floating point instructions for calculating the log, sine, cosine and such stuff. When I ran this program on the PowerPC it took almost 2 minutes to perform 1000 iterations at 100MHz. Then we wanted the code to run a little more faster and so we implemented the same design at 300MHz. Even if we didn't expect a three fold increase in speed, there was only an improvement of a couple of seconds. Can somebody tell me the reason.
Well about the memory that I was using, I used a OCM interface with 32kB for Instruction and 8kB for data. Cache memory was given to the PLB RAM(16kB). There was infact no speed difference with and without the cache memories !! Can somebody please help.
When I selected 300MHz for the processor, the maximum bus freq that I could select was only 100MHz. But this is only for the PLB or is it also for the OCM interface. (I always uses the wizard to build a new system, as I am quite new to tis stuff)
Thank you very much Joey