Dear experts,
I can't find any information whether d-cache could be used in ARMv8-A with disabled MMU. I found smth here -
http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.faqs/ka8788.html, but it seems not related to ARMv8-A.
Thank you!
Hi Stuart Hirons,
Thank you for detailed explanation! So AFAIU when MMU is disabled I can't use for example "prfm" cpu instruction to preload data into cache, because memory is handled as device memory, right?
Correct, scopichmu
You need to have the MMU enabled. This should be done on start up as the performance of the core will be poor otherwise (no D$ enabled, no speculative prefetching as memory is being treated as Device mem and core can't perform speculative accesses to Device memory)
If you have access to Arm's Development Studio tools then there are several Arm v8-A start-up examples included within there.
Regards
Stuart
Thank you, Stuart Hirons!