Hello,
I'm working with i.MX8DX (Dual Core CortexA35 + CortexM4) with the following simplified caching system:
My need is to flush a cached memory area to RAM in order to be viewed by the M4 core, unfortunately this area maybe cached by Core 0 and Core 1, something like this:
If Core 0 "only" did execute the assembly instruction (DC CIVAC) on address X for lines equal to size Y, on both L1 and L2, will the data cached by Core 1 also be cleaned and invalidated to RAM?
If not, do I need to execute (DC CIVAC) on both Core0 and Core1? Or there is another system-wide call that can be executed on Core 0 only to do the job?
Also, how can I test a behavior like this? Any advice?
Thanks in Advance.
There is only cache coherence between the CA cores. Means Core1 cache gets updated when core 0 writes back. As for the CM4 you should consider it as any other slave and memory it reads should be flushed whenever written.
Thank you for the reply.
I'll re-formalize my question.
Is there a possible way to flush the caches of Core 0 and Core 1 for a certain address range from Core 0 only? And is there a way to test this?
Thanks in advance.