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BIOS profiling not matching cycle counts

Started by Jeff Brower October 8, 2010
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We're using Clock_getTicks() BIOS API to profile code. Results do not match cycle counts by a factor of 10: about 50
sec vs. expectation of 5 sec (cycle counts determined by looking at generated .asm). We're using CCS 4.2, BIOS6, and
EVM C6472. All code and data is in onchip RAM, the only interrupt enabled is TIMER0 for BIOS.

A few questions:

1) Is there any reason not to use BIOS APIs for C64x+ profiling? For example we could disable interrupts, read TIMER0
directly, then re-enable interrupts...

2) In CCS 4.2 there doesn't appear to be a Free Run option (as in CCS 3.x). What is the best way to verify that CCS
is not "doing something" over JTAG during the measurement?

3) If pipeline stalls are occurring for any reason, what is the best way to determine and/or measure?

-Jeff

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