Hi6220 Mailbox

modulename: hi6220-mailbox.ko

configname: CONFIG_HI6220_MBOX

Linux Kernel Configuration
└─>Device Drivers
└─>Mailbox Hardware Support
└─>Device Tree and Open Firmware support
└─>Hi6220 Mailbox
In linux kernel since version 4.1 (release Date: 2015-06-21)  
An implementation of the hi6220 mailbox. It is used to send message
between application processors and MCU. Say Y here if you want to
build Hi6220 mailbox controller driver.

source code:
depends
CONFIG_MAILBOX
CONFIG_OF
CONFIG_ARCH_HISI or CONFIG_COMPILE_TEST