CONFIG_XTENSA_MX (not configurable)

modulename: irq-xtensa-mx.ko

configname: CONFIG_XTENSA_MX

Linux Kernel Configuration
└─>Device Drivers
└─>IRQ chip support
└─>XTENSA_MX
In linux kernel since version 3.10 (release Date: 2013-06-30)  
source code:
drivers/irqchip/irq-xtensa-mx.c
selects
CONFIG_IRQ_DOMAIN
CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK

is depended by
CONFIG_HAVE_SMP