When the MMU is disabled (CONFIG_ARCH_USE_MMU=n) the
data passed back and forth with the TEE needs to be
synced from/to the cache, otherwise we get random data
in either world.
Fix this by cleaning before a call and invalidating after.
This has to be done both on the optee msg arg, and the shm
buffers therein. Cleaning and invalidating the page list
used to describe non-contiguous shm buffers did not seem
mandatory in my tests, but common sense says that it should
be, so we do that too.
This fix does not apply to the optee msg arg of the socket
transport (optee_socket.c), as that one _should_ be handled
by the socket send/recv methods. It does apply to all shm
buffers though, regardless of transport.
Signed-off-by: George Poulios <gpoulios@census-labs.com>