mach-k3: enable mmu after reserved memory is unmapped

Currently the sequence to enable caches for the A53/A72 core on K3
devices looks as follows:

 1. Map entire DDR banks
 2. Setup page tables (done by mmu_setup)
 3. Enable MMU
 4. Unmap reserved-memory regions
 5. Enable caches

However there is a brief period of execution between #3 and #4 where the
core can issue speculative accesses to the entire DDR space (including
the reserved-memory regions) despite the caches being disabled.

A firewall exception is triggered whenever such speculative access is
made to secure DDR region of TFA or OP-TEE. This patch fixes the issue
by re-ordering the sequence as follows:

 1. Map entire DDR banks
 2. Setup page tables
 3. Unmap reserved-memory regions
 4. Enable MMU
 5. Enable caches

Fixes: f1c694b8fdde ("mach-k3: map all banks using mem_map_from_dram_banks")
Reported-by: Suhaas Joshi <[email protected]>
Signed-off-by: Anshul Dalal <[email protected]>
Reviewed-by: Ilias Apalodimas <[email protected]>

0 files changed, 0 insertions, 0 deletions