[ARM] 4500/1: Add locking around the background L2x0 cache operations
The background operations of the L2x0 cache controllers are aborted if
another operation is issued on the same or different core. This patch
protects the maintenance operation issuing/polling with a spinlock.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
authored by Catalin Marinas and committed by Russell King 07620976 13a63ab2