It's not a great surprise that crypto functions run better as 64-bit code on a 64-bit processor but you may hit two challenges running aarch64 LE images. The first is there are no aarch64 binary addons in our repo; because there are no official LE 9.0 aarch64 images. The second is addons requiring libwidevine (e.g. Netflix/Amazon) will not work as there are no 64-bit 'arm' versions of the lib in circulation to use. Being able to access DRM protected services is a hallmark feature/capability for Kodi 18 so this is the primary reason LE moved from aarch64 in LE 8.x releases to a split 64-bit kernel and 32-bit userspace arrangement (the same as Android) for LE 9.0
Darn, I totally forgot that. Makes sense. So no aarch64 then.
But yeah, I will move the rock64 specific crypto discussion (e.g. rk_crypto) somewhere else, as my intent for creating this thread was - for the most part - to understand what cryptodev does in this particular LL setup (is that an ARM thing? Rockchip specific? Or else?).