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Vybrid Cortex-A5 cache access latency

Question asked by a a on Jun 13, 2016
Latest reply on Jun 17, 2016 by Timesys Support


On "Understand Vybrid Architecture" cache access latency

Processor registers 1 cycle

On-chip L1 cache 1-2 cycles

On-chip L2 cache 8 cycles

Main memory, L3, dynamic RAM  30-100 cycles

Back-up memory, hard disk, L4  > 500 cycles

 

But I used DS-5 to measure cache access latency

I got

L1 cache read hit 32 cycle, write hit 3 cycle

when LDR follows STR it becomes 71 cycle on hit

 

How does that happen?

Are there more accurate numbers of cache access latency for vybrid VF6xx processor?

 

I found that data caching was disabled by default, beside SCTLR.C what should I set to enable it?

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