Architecturally, Set/Way operations are not guaranteed to affect all
caches prior to the PoC, and may require other IMPLEMENTATION DEFINED
maintenance (e.g. MMIO control of system-level caches).
First of all this patch was designed for Xen domain Zephyr build, set/way
ops are not easily virtualized by Xen. S/W emulation is disabled, because
IP-MMU is active for Dom0. IP-MMU is a IO-MMU made by Renesas, as any good
IO-MMU, it shares page-tables with CPU. Trying to emulate S/W with IP-MMU
active will lead to IO-MMU faults. So if we build Zephyr as a Xen Initial
domain, it won't work with cache management support enabled.
Exposing set/way cache maintenance to a virtual machine is unsafe, not
least because the instructions are not permission-checked, but also
because they are not broadcast between CPUs.
In this commit, VA data invalidate invoked after every mapping instead of
using set/way instructions on init MMU. So, it was easy to delete
sys_cache_data_invd_all from enable MMU function, becase every adding of
a new memory region to xclat tabes will cause invalidating of this memory
and in this way we sure that there are not any stale data inside.
Signed-off-by: Mykola Kvach <mykola_kvach@epam.com>
c9b534c4eb